Edward A. Fisher, Ph.D., M.P.H., M.D.

The neuroimmune guidance cue netrin-1 promotes atherosclerosis by inhibiting the emigration of macrophages from plaques
van Gils JM; Derby MC; Fernandes LR; Ramkhelawon B; Ray TD; Rayner KJ; Parathath S; Distel E; Feig JL; Alvarez-Leite JI; Rayner AJ; McDonald TO; O'Brien KD; Stuart LM; Fisher EA; Lacy-Hulbert A; Moore KJ
2012 ;13(2):136-43 L, Nature immunology
Atherosclerotic plaque formation is fueled by the persistence of lipid-laden macrophages in the artery wall. The mechanisms by which these cells become trapped, thereby establishing chronic inflammation, remain unknown. Here we found that netrin-1, a neuroimmune guidance cue, was secreted by macrophages in human and mouse atheroma, where it inactivated the migration of macrophages toward chemokines linked to their egress from plaques. Acting via its receptor, UNC5b, netrin-1 inhibited the migration of macrophages directed by the chemokines CCL2 and CCL19, activation of the actin-remodeling GTPase Rac1 and actin polymerization. Targeted deletion of netrin-1 in macrophages resulted in much less atherosclerosis in mice deficient in the receptor for low-density lipoprotein and promoted the emigration of macrophages from plaques. Thus, netrin-1 promoted atherosclerosis by retaining macrophages in the artery wall. Our results establish a causative role for negative regulators of leukocyte migration in chronic inflammation
— id: 149862, year: 2012, vol: 13, page: 136, stat: Journal Article,

Role of superoxide radical anion in the mechanism of apoB100 degradation induced by DHA in hepatic cells
Andreo, Ursula; Elkind, Josh; Blachford, Courtney; Cederbaum, Arthur I; Fisher, Edward A
2011 Oct;25(10):3554-3560, FASEB journal
VLDL is produced by the liver. Its major protein is apoB100. Docosahexaenoic acid (DHA), a dietary polyunsaturated fatty acid (PUFA), reduces VLDL levels and is used therapeutically for hypertriglyceridemia. In model systems, DHA lowers VLDL secretion by inducing presecretory apoB100 degradation, a process dependent on PUFA-derived lipid peroxides. We hypothesized that superoxide (SO) was a major participant in DHA-induced apoB100 degradation, given its promotion of lipid peroxidation. SO levels in a model of VLDL metabolism, rat hepatoma McArdle cells, were either decreased by a mimetic of superoxide dismutase 1 (SOD1) or by overexpressing SOD1 or increased by SOD1 siRNA. ApoB100 recovery was assessed by immunoprecipitation, SO by 2-hydroxyethidine, and lipid peroxides by thiobarbituric acid reactive substances. The SOD1 mimetic or SOD1 overexpression reduced SO and inhibited apoB100 degradation in DHA-treated cells by up to 100%. Surprisingly, silencing SOD1 did not increase DHA-induced degradation, although levels of SO were higher (+44%); those of lipid peroxides were similar, and their reduction by alpha-tocopherol decreased degradation by 50%. SO is required for lipid peroxidation in DHA-induced apoB100 degradation, but it is the peroxide level that has a tighter relationship to the level of degradation and the regulation of VLDL production.-Andreo, U., Elkind, J., Blachford, C., Cederbaum, A. I., Fisher, E. A. Role of superoxide radical anion in the mechanism of apoB100 degradation induced by DHA in hepatic cells
— id: 138107, year: 2011, vol: 25, page: 3554, stat: Journal Article,

Cholesterol 27-Hydroxylase but Not Apolipoprotein apoE Contributes to A(2A) Adenosine Receptor Stimulated Reverse Cholesterol Transport
Bingham TC; Parathath S; Tian H; Reiss A; Chan E; Fisher EA; Cronstein BN
2011 Jan 22;:?-? #, Inflammation
Movement of free cholesterol between the cellular compartment and acceptor is governed by cholesterol gradients that are determined by several enzymes and reverse cholesterol transport proteins. We have previously demonstrated that adenosine A(2A) receptors inhibit foam cell formation and stimulate production of cholesterol 27-hydroxylase (CYP27A1), an enzyme involved in the conversion of cholesterol to oxysterols. We therefore asked whether the effect of adenosine A(2A) receptors on foam cell formation in vitro is mediated by CYP27A1 or apoE, a carrier for cholesterol in the serum. We found that specific lentiviral siRNA infection markedly reduced apoE or 27-hydroxylase mRNA in THP-1 cells. Despite diminished apoE expression (p < 0.0002, interferon-gamma (IFNgamma) CGS vs. IFNgamma alone, n = 4), CGS-21680, an adenosine A(2A) receptor agonist, inhibits foam cell formation. In contrast, CGS-21680 had no effect on reducing foam cell formation in CYP27A1 KD cells (4 +/- 2%; p < 0.5113, inhibition vs. IFNgamma alone, n = 4). Previously, we reported the A(2A) agonist CGS-21680 increases apoAI-mediated cholesterol efflux nearly twofold in wild-type macrophages. Adenosine receptor activation had no effect on cholesterol efflux in CYP27A1 KD cells but reduced efflux in apoE KD cells. These results demonstrate that adenosine A(2A) receptor occupancy diminishes foam cell formation by increasing expression and function of CYP27A1
— id: 122556, year: 2011, vol: , page: ?, stat: Journal Article,

Different fatty acids inhibit apoB100 secretion by different pathways: unique roles for ER stress, ceramide, and autophagy
Caviglia, Jorge Matias; Gayet, Constance; Ota, Tsuguhito; Hernandez-Ono, Antonio; Conlon, Donna M.; Jiang, Hongfeng; Fisher, Edward A.; Ginsberg, Henry N.
2011 SEP ;52(9):1636-1651, Journal of lipid research
Although short-term incubation of hepatocytes with oleic acid (OA) stimulates secretion of apolipoprotein B100 (apoB100), exposure to higher doses of OA for longer periods inhibits secretion in association with induction of endoplasmic reticulum (ER) stress. Palmitic acid (PA) induces ER stress, but its effects on apoB100 secretion are unclear. Docosahexaenoic acid (DHA) inhibits apoB100 secretion, but its effects on ER stress have not been studied. We compared the effects of each of these fatty acids on ER stress and apoB100 secretion in McArdle RH7777 (McA) cells: OA and PA induced ER stress and inhibited apoB100 secretion at higher doses; PA was more potent because it also increased the synthesis of ceramide. DHA did not induce ER stress but was the most potent inhibitor of apoB100 secretion, acting via stimulation of autophagy. These unique effects of each fatty acid were confirmed when they were infused into C57BL6J mice. Our results suggest that when both increased hepatic secretion of VLDL apoB100 and hepatic steatosis coexist, reducing ER stress might alleviate hepatic steatosis but at the expense of increased VLDL secretion. In contrast, increasing autophagy might reduce VLDL secretion without causing steatosis.-Caviglia, J. M., C. Gayet, T. Ota, A. Hernandez-Ono, D. M. Conlon, H. Jiang, E. A. Fisher, and H. N. Ginsberg. Different fatty acids inhibit apoB100 secretion by different pathways: unique roles for ER stress, ceramide, and autophagy. J. Lipid Res. 2011. 52: 1636-1651
— id: 136980, year: 2011, vol: 52, page: 1636, stat: Journal Article,

Triglyceride-rich lipoproteins and high-density lipoprotein cholesterol in patients at high risk of cardiovascular disease: evidence and guidance for management
Chapman, M. John; Ginsberg, Henry N.; Amarenco, Pierre; Andreotti, Felicita; Boren, Jan; Catapano, Alberico L.; Descamps, Olivier S.; Fisher, Edward; Kovanen, Petri T.; Kuivenhoven, Jan Albert; Lesnik, Philippe; Masana, Luis; Nordestgaard, Borge G.; Ray, Kausik K.; Reiner, Zeljko; Taskinen, Marja-Riitta; Tokgozoglu, Lale; Tybjaerg-Hansen, Anne; Watts, Gerald F.;
2011 JUN ;32(11):1345-1361, European heart journal
Even at low-density lipoprotein cholesterol (LDL-C) goal, patients with cardiometabolic abnormalities remain at high risk of cardiovascular events. This paper aims (i) to critically appraise evidence for elevated levels of triglyceride-rich lipoproteins (TRLs) and low levels of high-density lipoprotein cholesterol (HDL-C) as cardiovascular risk factors, and (ii) to advise on therapeutic strategies for management. Current evidence supports a causal association between elevated TRL and their remnants, low HDL-C, and cardiovascular risk. This interpretation is based on mechanistic and genetic studies for TRL and remnants, together with the epidemiological data suggestive of the association for circulating triglycerides and cardiovascular disease. For HDL, epidemiological, mechanistic, and clinical intervention data are consistent with the view that low HDL-C contributes to elevated cardiovascular risk; genetic evidence is unclear however, potentially reflecting the complexity of HDL metabolism. The Panel believes that therapeutic targeting of elevated triglycerides (>= 1.7 mmol/L or 150 mg/dL), a marker of TRL and their remnants, and/or low HDL-C (< 1.0 mmol/L or 40 mg/dL) may provide further benefit. The first step should be lifestyle interventions together with consideration of compliance with pharmacotherapy and secondary causes of dyslipidaemia. If inadequately corrected, adding niacin or a fibrate, or intensifying LDL-C lowering therapy may be considered. Treatment decisions regarding statin combination therapy should take into account relevant safety concerns, i. e. the risk of elevation of blood glucose, uric acid or liver enzymes with niacin, and myopathy, increased serum creatinine and cholelithiasis with fibrates. These recommendations will facilitate reduction in the substantial cardiovascular risk that persists in patients with cardiometabolic abnormalities at LDL-C goal
— id: 140681, year: 2011, vol: 32, page: 1345, stat: Journal Article,

miR-33a/b contribute to the regulation of fatty acid metabolism and insulin signaling
Davalos, Alberto; Goedeke, Leigh; Smibert, Peter; Ramirez, Cristina M; Warrier, Nikhil P; Andreo, Ursula; Cirera-Salinas, Daniel; Rayner, Katey; Suresh, Uthra; Pastor-Pareja, Jose Carlos; Esplugues, Enric; Fisher, Edward A; Penalva, Luiz O F; Moore, Kathryn J; Suarez, Yajaira; Lai, Eric C; Fernandez-Hernando, Carlos
2011 May 31;108(22):9232-9237, Proceedings of the National Academy of Sciences of the United States of America
Cellular imbalances of cholesterol and fatty acid metabolism result in pathological processes, including atherosclerosis and metabolic syndrome. Recent work from our group and others has shown that the intronic microRNAs hsa-miR-33a and hsa-miR-33b are located within the sterol regulatory element-binding protein-2 and -1 genes, respectively, and regulate cholesterol homeostasis in concert with their host genes. Here, we show that miR-33a and -b also regulate genes involved in fatty acid metabolism and insulin signaling. miR-33a and -b target key enzymes involved in the regulation of fatty acid oxidation, including carnitine O-octaniltransferase, carnitine palmitoyltransferase 1A, hydroxyacyl-CoA-dehydrogenase, Sirtuin 6 (SIRT6), and AMP kinase subunit-alpha. Moreover, miR-33a and -b also target the insulin receptor substrate 2, an essential component of the insulin-signaling pathway in the liver. Overexpression of miR-33a and -b reduces both fatty acid oxidation and insulin signaling in hepatic cell lines, whereas inhibition of endogenous miR-33a and -b increases these two metabolic pathways. Together, these data establish that miR-33a and -b regulate pathways controlling three of the risk factors of metabolic syndrome, namely levels of HDL, triglycerides, and insulin signaling, and suggest that inhibitors of miR-33a and -b may be useful in the treatment of this growing health concern
— id: 133351, year: 2011, vol: 108, page: 9232, stat: Journal Article,

Reversal of hyperlipidemia with a genetic switch favorably affects the content and inflammatory state of macrophages in atherosclerotic plaques
Feig, Jonathan E; Parathath, Sajesh; Rong, James X; Mick, Stephanie L; Vengrenyuk, Yuliya; Grauer, Lisa; Young, Stephen G; Fisher, Edward A
2011 Mar 8;123(9):989-998, Circulation
BACKGROUND: We previously showed that the progression of atherosclerosis in the Reversa mouse (Ldlr(-/-Apob100/100Mttpfl/fl) Mx1Cre(+/+)) was arrested when the hyperlipidemia was normalized by inactivating the gene for microsomal triglyceride transfer protein. Here, we tested whether atherosclerosis would regress if the lipid levels were reduced after advanced plaques formed. METHODS AND RESULTS: Reversa mice were fed an atherogenic diet for 16 weeks. Plasma lipid levels were then reduced. Within 2 weeks, this reduction led to decreased monocyte-derived (CD68(+)) cells in atherosclerotic plaques and was associated with emigration of these cells out of plaques. In addition, the fall in lipid levels was accompanied by lower plaque lipid content and by reduced expression in plaque CD68(+) cells of inflammatory genes and higher expression of genes for markers of antiinflammatory M2 macrophages. Plaque composition was affected more than plaque size, with the decreased content of lipid and CD68(+) cells balanced by a higher content of collagen. When the reduced lipid level was combined with the administration of pioglitazone to simulate the clinical aggressive lipid management and proliferator-activated receptor-gamma agonist treatment, the rate of depletion of plaque CD68(+) cells was unaffected, but there was a further increase in their expression of antiinflammatory macrophage markers. CONCLUSION: The Reversa mouse is a new model of atherosclerosis regression. After lipid lowering, favorable changes in plaque composition were independent of changes in size. In addition, plaque CD68(+) cells became less inflammatory, an effect enhanced by treatment with pioglitazone
— id: 134117, year: 2011, vol: 123, page: 989, stat: Journal Article,

HDL promotes rapid atherosclerosis regression in mice and alters inflammatory properties of plaque monocyte-derived cells
Feig, Jonathan E; Rong, James X; Shamir, Raanan; Sanson, Marie; Vengrenyuk, Yuliya; Liu, Jianhua; Rayner, Katey; Moore, Kathryn; Garabedian, Michael; Fisher, Edward A
2011 Apr 26;108(17):7166-7171, Proceedings of the National Academy of Sciences of the United States of America
HDL cholesterol (HDL-C) plasma levels are inversely related to cardiovascular disease risk. Previous studies have shown in animals and humans that HDL promotes regression of atherosclerosis. We hypothesized that this was related to an ability to promote the loss of monocyte-derived cells (CD68(+), primarily macrophages and macrophage foam cells) from plaques. To test this hypothesis, we used an established model of atherosclerosis regression in which plaque-bearing aortic arches from apolipoprotein E-deficient (apoE(-/-)) mice (low HDL-C, high non-HDL-C) were transplanted into recipient mice with differing levels of HDL-C and non-HDL-C: C57BL6 mice (normal HDL-C, low non-HDL-C), apoAI(-/-) mice (low HDL-C, low non-HDL-C), or apoE(-/-) mice transgenic for human apoAI (hAI/apoE(-/-); normal HDL-C, high non-HDL-C). Remarkably, despite persistent elevated non-HDL-C in hAI/apoE(-/-) recipients, plaque CD68(+) cell content decreased by >50% by 1 wk after transplantation, whereas there was little change in apoAI(-/-) recipient mice despite hypolipidemia. The decreased content of plaque CD68(+) cells after HDL-C normalization was associated with their emigration and induction of their chemokine receptor CCR7. Furthermore, in CD68(+) cells laser-captured from the plaques, normalization of HDL-C led to decreased expression of inflammatory factors and enrichment of markers of the M2 (tissue repair) macrophage state. Again, none of these beneficial changes were observed in the apoAI(-/-) recipients, suggesting a major requirement for reverse cholesterol transport for the beneficial effects of HDL. Overall, these results establish HDL as a regulator in vivo of the migratory and inflammatory properties of monocyte-derived cells in mouse atherosclerotic plaques, and highlight the phenotypic plasticity of these cells
— id: 131816, year: 2011, vol: 108, page: 7166, stat: Journal Article,

Statins Promote the Regression of Atherosclerosis via Activation of the CCR7-Dependent Emigration Pathway in Macrophages
Feig, Jonathan E; Shang, Yueting; Rotllan, Noemi; Vengrenyuk, Yuliya; Wu, Chaowei; Shamir, Raanan; Torra, Ines Pineda; Fernandez-Hernando, Carlos; Fisher, Edward A; Garabedian, Michael J
2011 ;6(12):e28534-e28534, PLoS ONE
HMG-CoA reductase inhibitors (statins) decrease atherosclerosis by lowering low-density-lipoprotein cholesterol. Statins are also thought to have additional anti-atherogenic properties, yet defining these non-conventional modes of statin action remains incomplete. We have previously developed a novel mouse transplant model of atherosclerosis regression in which aortic segments from diseased donors are placed into normolipidemic recipients. With this model, we demonstrated the rapid loss of CD68+ cells (mainly macrophages) in plaques through the induction of a chemokine receptor CCR7-dependent emigration process. Because the human and mouse CCR7 promoter contain Sterol Response Elements (SREs), we hypothesized that Sterol Regulatory Element Binding Proteins (SREBPs) are involved in increasing CCR7 expression and through this mechanism, statins would promote CD68+ cell emigration from plaques. We examined whether statin activation of the SREBP pathway in vivo would induce CCR7 expression and promote macrophage emigration from plaques. We found that western diet-fed apoE(-/-) mice treated with either atorvastatin or rosuvastatin led to a substantial reduction in the CD68+ cell content in the plaques despite continued hyperlipidemia. We also observed a significant increase in CCR7 mRNA in CD68+ cells from both the atorvastatin and rosuvastatin treated mice associated with emigration of CD68+ cells from plaques. Importantly, CCR7(-/-)/apoE(-/-) double knockout mice failed to display a reduction in CD68+ cell content upon statin treatment. Statins also affected the recruitment of transcriptional regulatory proteins and the organization of the chromatin at the CCR7 promoter to increase the transcriptional activity. Statins promote the beneficial remodeling of plaques in diseased mouse arteries through the stimulation of the CCR7 emigration pathway in macrophages. Therefore, statins may exhibit some of their clinical benefits by not only retarding the progression of atherosclerosis, but also accelerating its regression
— id: 146266, year: 2011, vol: 6, page: e28534, stat: Journal Article,

Introduction for national cholesterol month
Fisher, Edward A
2011 Sep;31(9):1939-1940, Arteriosclerosis, thrombosis, & vascular biology
— id: 136642, year: 2011, vol: 31, page: 1939, stat: Journal Article,

The editor in chief position in transition
Fisher, Edward A
2011 Jul;31(7):1461-1461, Arteriosclerosis, thrombosis, & vascular biology
— id: 134466, year: 2011, vol: 31, page: 1461, stat: Journal Article,

Huh-7 or HepG2 cells: which is the better model for studying human apolipoprotein-B100 assembly and secretion?
Meex, Steven J R; Andreo, Ursula; Sparks, Janet D; Fisher, Edward A
2011 Jan;52(1):152-158, Journal of lipid research
Apolipoprotein-B100 (apoB100) is the essential protein for the assembly and secretion of very low density lipoproteins (VLDL) from liver. The hepatoma HepG2 cell line has been the cell line of choice for the study of synthesis and secretion of human apoB-100. Despite the general use of HepG2 cells to study apoB100 metabolism, they secrete relatively dense, lipid-poor particles compared with VLDL secreted in vivo. Recently, Huh-7 cells were adopted as an alternative model to HepG2 cells, with the implicit assumption that Huh-7 cells were superior in some respects of lipoprotein metabolism, including VLDL secretion. In this study we addressed the hypothesis that the spectrum of apoB100 lipoprotein particles secreted by Huh-7 cells more closely resembles the native state in human liver. We find that Huh-7 cells resemble HepG2 cells in the effects of exogenous lipids, microsomal triglyceride transfer protein (MTP)-inhibition, and proteasome inhibitors of apoB100 secretion, recovery, and degradation. In contrast to HepG2 cells, however, MEK-ERK inhibition does not correct the defect in VLDL secretion. Huh-7 cells do not appear to offer any advantages over HepG2 cells as a general model of human apoB100-lipoprotein metabolism
— id: 115422, year: 2011, vol: 52, page: 152, stat: Journal Article,

Rat Carboxylesterase ES-4 Enzyme Functions as a Major Hepatic Neutral Cholesteryl Ester Hydrolase
Parathath, Saj; Dogan, Snjezana; Joaquin, Victor A; Ghosh, Snigdha; Guo, Liang; Weibel, Ginny L; Rothblat, George H; Harrison, Earl H; Fisher, Edward A
2011 Nov 18;286(46):39683-39692, Journal of biological chemistry
Although esterification of free cholesterol to cholesteryl ester in the liver is known to be catalyzed by the enzyme acyl-coenzyme A:cholesterol acyltransferase, ACAT, the neutral cholesteryl ester hydrolase (nCEH) that catalyzes the reverse reaction has remained elusive. Because cholesterol undergoes continuous cycling between free and esterified forms, the steady-state concentrations in the liver of the two species and their metabolic availability for pathways, such as lipoprotein assembly and bile acid synthesis, depend upon nCEH activity. On the basis of the general characteristics of the family of rat carboxylesterases, we hypothesized that one member, ES-4, was a promising candidate as a hepatic nCEH. Using under- and overexpression approaches, we provide multiple lines of evidence that establish ES-4 as a bona fide endogenous nCEH that can account for the majority of cholesteryl ester hydrolysis in transformed rat hepatic cells and primary rat hepatocytes
— id: 141488, year: 2011, vol: 286, page: 39683, stat: Journal Article,

Diabetes adversely affects macrophages during atherosclerotic plaque regression in mice
Parathath, Saj; Grauer, Lisa; Huang, Li-Shin; Sanson, Marie; Distel, Emilie; Goldberg, Ira J; Fisher, Edward A
2011 Jun;60(6):1759-1769, Diabetes
OBJECTIVE: Patients with diabetes have increased cardiovascular risk. Atherosclerosis in these patients is often associated with increased plaque macrophages and dyslipidemia. We hypothesized that diabetic atherosclerosis involves processes that impair favorable effects of lipid reduction on plaque macrophages. RESEARCH DESIGN AND METHODS: Reversa mice are LDL receptor-deficient mice that develop atherosclerosis. Their elevated plasma LDL levels are lowered after conditional knockout of the gene encoding microsomal triglyceride transfer protein. We examined the morphologic and molecular changes in atherosclerotic plaques in control and streptozotocin-induced diabetic Reversa mice after LDL lowering. Bone marrow-derived macrophages were also used to study changes mediated by hyperglycemia. RESULTS: Reversa mice were fed a western diet for 16 weeks to develop plaques (baseline). Four weeks after lipid normalization, control (nondiabetic) mice had reduced plasma cholesterol (-77%), plaque cholesterol (-53%), and plaque cells positive for macrophage marker CD68+ (-73%), but increased plaque collagen (+116%) compared with baseline mice. Diabetic mice had similarly reduced plasma cholesterol, but collagen content increased by only 34% compared with baseline; compared with control mice, there were lower reductions in plaque cholesterol (-30%) and CD68+ cells (-41%). Diabetic (vs. control) plaque CD68+ cells also exhibited more oxidant stress and inflammatory gene expression and less polarization toward the anti-inflammatory M2 macrophage state. Many of the findings in vivo were recapitulated by hyperglycemia in mouse bone marrow-derived macrophages. CONCLUSIONS: Diabetes hindered plaque regression in atherosclerotic mice (based on CD68+ plaque content) and favorable changes in plaque macrophage characteristics after the reduction of elevated plasma LDL
— id: 134719, year: 2011, vol: 60, page: 1759, stat: Journal Article,

Hypoxia is present in murine atherosclerotic plaques and has multiple adverse effects on macrophage lipid metabolism
Parathath, Sajesh; Mick, Stephanie L; Feig, Jonathan E; Joaquin, Victor; Grauer, Lisa; Habiel, David M; Gassmann, Max; Gardner, Lawrence B; Fisher, Edward A
2011 Oct 28;109(10):1141-1152, Circulation research
Rationale: Human atherosclerotic plaques contain large numbers of cells deprived of O(2). In murine atherosclerosis, because the plaques are small, it is controversial whether hypoxia can occur. Objective: To examine if murine plaques contain hypoxic cells, and whether hypoxia regulates changes in cellular lipid metabolism and gene expression in macrophages. Methods and Results: Aortic plaques from apolipoprotein-E-deficient mice were immunopositive for hypoxia-inducible transcription factor (HIF-1alpha) and some of its downstream targets. Murine J774 macrophages rendered hypoxic demonstrated significant increases in cellular sterol and triglycerides. The increase in sterol content in hypoxic macrophages correlated with elevated 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase activity and mRNA levels. In addition, when macrophages were incubated with cholesterol complexes, hypoxic cells accumulated 120% more cholesterol, predominately in the free form. Cholesterol-efflux assays showed that hypoxia significantly decreased efflux mediated by ATP-binding cassette subfamily A member 1 (ABCA1), whose sub cellular localization was altered in both J774 and primary macrophages. Furthermore, in vivo expression patterns of selected genes from cells in hypoxic regions of murine plaques were similar to those from J774 and primary macrophages incubated in hypoxia. The hypoxia-induced accumulation of sterol and decreased cholesterol efflux was substantially reversed in vitro by reducing the expression of the hypoxia-inducible transcription factor, HIF-1alpha. Conclusion: Hypoxic regions are present in murine plaques. Hypoxic macrophages have increased sterol content due to the induction of sterol synthesis and the suppression of cholesterol efflux, effects that are in part mediated by HIF-1alpha
— id: 140525, year: 2011, vol: 109, page: 1141, stat: Journal Article,

LXR{alpha} Regulates Macrophage Arginase 1 Through PU.1 and Interferon Regulatory Factor 8
Pourcet, Benoit; Feig, Jonathan E; Vengrenyuk, Yuliya; Hobbs, Adrian J; Kepka-Lenhart, Diane; Garabedian, Michael J; Morris, Sidney M Jr; Fisher, Edward A; Pineda-Torra, Ines
2011 Aug 19;109(5):492-501, Circulation research
Rationale: Activation of liver X receptors (LXRs) inhibits the progression of atherosclerosis and promotes regression of existing lesions. In addition, LXRalpha levels are high in regressive plaques. Macrophage arginase 1 (Arg1) expression is inversely correlated with atherosclerosis progression and is markedly decreased in foam cells within the lesion. Objective: To investigate LXRalpha regulation of Arg1 expression in cultured macrophages and atherosclerotic regressive lesions. Methods and Results: We found that Arg1 expression is enhanced in CD68+ cells from regressive versus progressive lesions in a murine aortic arch transplant model. In cultured macrophages, ligand-activated LXRalpha markedly enhances basal and interleukin-4-induced Arg1 mRNA and protein expression as well as promoter activity. This LXRalpha-enhanced Arg1 expression correlates with a reduction in nitric oxide levels. Moreover, Arg1 expression within regressive atherosclerotic plaques is LXRalpha-dependent, as enhanced expression of Arg1 in regressive lesions is impaired in LXRalpha-deficient CD68+ cells. LXRalpha does not bind to the Arg1 promoter but instead promotes the interaction between PU.1 and interferon regulatory factor (IRF)8 transcription factors and induces their binding of a novel composite element. Accordingly, knockdown of either IRF8 or PU.1 strongly impairs LXRalpha regulation of Arg1 expression in macrophage cells. Finally, we demonstrate that LXRalpha binds the IRF8 locus and its activation increases IRF8 mRNA and protein levels in these cells. Conclusions: This work implicates Arg1 in atherosclerosis regression and identifies LXRalpha as a novel regulator of Arg1 and IRF8 in macrophages. Furthermore, it provides a unique molecular mechanism by which LXRalpha regulates macrophage target gene expression through PU.1 and IRF8
— id: 137018, year: 2011, vol: 109, page: 492, stat: Journal Article,

Inhibition of miR-33a/b in non-human primates raises plasma HDL and lowers VLDL triglycerides
Rayner, Katey J; Esau, Christine C; Hussain, Farah N; McDaniel, Allison L; Marshall, Stephanie M; van Gils, Janine M; Ray, Tathagat D; Sheedy, Frederick J; Goedeke, Leigh; Liu, Xueqing; Khatsenko, Oleg G; Kaimal, Vivek; Lees, Cynthia J; Fernandez-Hernando, Carlos; Fisher, Edward A; Temel, Ryan E; Moore, Kathryn J
2011 Oct 20;478(7369):404-407, Nature
Cardiovascular disease remains the leading cause of mortality in westernized countries, despite optimum medical therapy to reduce the levels of low-density lipoprotein (LDL)-associated cholesterol. The pursuit of novel therapies to target the residual risk has focused on raising the levels of high-density lipoprotein (HDL)-associated cholesterol in order to exploit its atheroprotective effects. MicroRNAs (miRNAs) have emerged as important post-transcriptional regulators of lipid metabolism and are thus a new class of target for therapeutic intervention. MicroRNA-33a and microRNA-33b (miR-33a/b) are intronic miRNAs whose encoding regions are embedded in the sterol-response-element-binding protein genes SREBF2 and SREBF1 (refs 3-5), respectively. These miRNAs repress expression of the cholesterol transporter ABCA1, which is a key regulator of HDL biogenesis. Recent studies in mice suggest that antagonizing miR-33a may be an effective strategy for raising plasma HDL levels and providing protection against atherosclerosis; however, extrapolating these findings to humans is complicated by the fact that mice lack miR-33b, which is present only in the SREBF1 gene of medium and large mammals. Here we show in African green monkeys that systemic delivery of an anti-miRNA oligonucleotide that targets both miR-33a and miR-33b increased hepatic expression of ABCA1 and induced a sustained increase in plasma HDL levels over 12 weeks. Notably, miR-33 antagonism in this non-human primate model also increased the expression of miR-33 target genes involved in fatty acid oxidation (CROT, CPT1A, HADHB and PRKAA1) and reduced the expression of genes involved in fatty acid synthesis (SREBF1, FASN, ACLY and ACACA), resulting in a marked suppression of the plasma levels of very-low-density lipoprotein (VLDL)-associated triglycerides, a finding that has not previously been observed in mice. These data establish, in a model that is highly relevant to humans, that pharmacological inhibition of miR-33a and miR-33b is a promising therapeutic strategy to raise plasma HDL and lower VLDL triglyceride levels for the treatment of dyslipidaemias that increase cardiovascular disease risk
— id: 139483, year: 2011, vol: 478, page: 404, stat: Journal Article,

Antagonism of miR-33 in mice promotes reverse cholesterol transport and regression of atherosclerosis
Rayner, Katey J; Sheedy, Frederick J; Esau, Christine C; Hussain, Farah N; Temel, Ryan E; Parathath, Saj; van Gils, Janine M; Rayner, Alistair J; Chang, Aaron N; Suarez, Yajaira; Fernandez-Hernando, Carlos; Fisher, Edward A; Moore, Kathryn J
2011 Jul 1;121(7):2921-2931, Journal of clinical investigation
Plasma HDL levels have a protective role in atherosclerosis, yet clinical therapies to raise HDL levels have remained elusive. Recent advances in the understanding of lipid metabolism have revealed that miR-33, an intronic microRNA located within the SREBF2 gene, suppresses expression of the cholesterol transporter ABC transporter A1 (ABCA1) and lowers HDL levels. Conversely, mechanisms that inhibit miR-33 increase ABCA1 and circulating HDL levels, suggesting that antagonism of miR-33 may be atheroprotective. As the regression of atherosclerosis is clinically desirable, we assessed the impact of miR-33 inhibition in mice deficient for the LDL receptor (Ldlr-/- mice), with established atherosclerotic plaques. Mice treated with anti-miR33 for 4 weeks showed an increase in circulating HDL levels and enhanced reverse cholesterol transport to the plasma, liver, and feces. Consistent with this, anti-miR33-treated mice showed reductions in plaque size and lipid content, increased markers of plaque stability, and decreased inflammatory gene expression. Notably, in addition to raising ABCA1 levels in the liver, anti-miR33 oligonucleotides directly targeted the plaque macrophages, in which they enhanced ABCA1 expression and cholesterol removal. These studies establish that raising HDL levels by anti-miR33 oligonucleotide treatment promotes reverse cholesterol transport and atherosclerosis regression and suggest that it may be a promising strategy to treat atherosclerotic vascular disease
— id: 136939, year: 2011, vol: 121, page: 2921, stat: Journal Article,

The biological properties of iron oxide core high-density lipoprotein in experimental atherosclerosis
Skajaa, Torjus; Cormode, David P; Jarzyna, Peter A; Delshad, Amanda; Blachford, Courtney; Barazza, Alessandra; Fisher, Edward A; Gordon, Ronald E; Fayad, Zahi A; Mulder, Willem J M
2011 Jan;32(1):206-213, Biomaterials
Lipoproteins are a family of plasma nanoparticles responsible for the transportation of lipids throughout the body. High-density lipoprotein (HDL), the smallest of the lipoprotein family, measures 7-13 nm in diameter and consists of a cholesteryl ester and triglyceride core that is covered with a monolayer of phospholipids and apolipoproteins. We have developed an iron oxide core HDL nanoparticle (FeO-HDL), which has a lipid based fluorophore incorporated in the phospholipid layer. This nanoparticle provides contrast for optical imaging, magnetic resonance imaging (MRI) and transmission electron microscopy (TEM). Consequently, FeO-HDL can be visualized on the anatomical, cellular and sub-cellular level. In the current study we show that the biophysical features of FeO-HDL closely resemble those of native HDL and that FeO-HDL possess the ability to mimic HDL characteristics both in vitro as well as in vivo. We demonstrate that FeO-HDL can be applied to image HDL interactions and to investigate disease settings where HDL plays a key function. More generally, we have demonstrated a multimodal approach to study the behavior of biomaterials in vitro as well as in vivo. The approach allowed us to study nanoparticle dynamics in circulation, as well as nanoparticle targeting and uptake by tissues and cells of interest. Moreover, we were able to qualitatively assess nanoparticle excretion, critical for translating nanotechnologies to the clinic
— id: 133199, year: 2011, vol: 32, page: 206, stat: Journal Article,

The presence, characterization and prognosis of coronary plaques among patients with zero coronary calcium scores
Uretsky, Seth; Rozanski, Alan; Singh, Padmakshi; Supariwala, Azhar; Atluri, Prashanth; Bangalore, Sripal; Pappas, Thomas W; Fisher, Edward A; Peters, M Robert
2011 Jul;27(6):805-812, International journal of cardiovascular imaging
Patients with coronary artery calcium (CAC) scores of zero are generally considered not to have atherosclerosis. Recent studies involving computed tomography coronary angiography (CTCA) challenge this assumption. This goal of the present study is to assess the frequency, morphology, location, and the prognosis of patients with plaque detected on CTCA and zero CAC. 1,119 patients (51 +/- 12 years, 52% male) with a zero CAC score during CTCA study were retrospectively identified. The CTCA studies were assessed for the presence, morphology, location and severity of all coronary plaques. All-cause mortality was assessed. The prevalence of coronary plaque was 13% (147 patients). Among the 212 plaques identified 154 (73%) were non-calcified, 28 (13%) were calcified, and 30 (14%) were of mixed morphology. Notably, >/=70% stenosis was noted among only 0.4% of all patients. ROC analysis revealed that coronary artery disease risk factors did not add to the prediction of plaque among our patients. Over a mean follow-up of 2.5 +/- 0.6 years there were 4 deaths (0.4%), all in patients without coronary plaque on CTCA. The presence of coronary plaque is not uncommon among patients with zero CAC scores. These plaques were rarely associated with hemodynamically significant stenoses and were associated with an excellent prognosis. Clinical factors do not appear to be useful in predicting which patients with zero CAC scores have undetected coronary plaque
— id: 138329, year: 2011, vol: 27, page: 805, stat: Journal Article,

Pioglitazone Modulates Vascular Inflammation in Atherosclerotic Rabbits Noninvasive Assessment With FDG-PET-CT and Dynamic Contrast-Enhanced MR Imaging
Vucic, Esad; Dickson, Stephen D; Calcagno, Claudia; Rudd, James H F; Moshier, Erin; Hayashi, Katsumi; Mounessa, Jessica S; Roytman, Michelle; Moon, Matthew J; Lin, James; Tsimikas, Sotirios; Fisher, Edward A; Nicolay, Klaas; Fuster, Valentin; Fayad, Zahi A
2011 Oct;4(10):1100-1109, JACC: Cardiovascular Imaging
OBJECTIVES: We sought to determine the antiatherosclerotic properties of pioglitazone using multimethod noninvasive imaging techniques. BACKGROUND: Inflammation is an essential component of vulnerable or high-risk atheromas. Pioglitazone, a peroxisome proliferator-activated receptor-gamma agonist, possesses potent anti-inflammatory properties. We aimed to quantify noninvasively the anti-inflammatory effects of pioglitazone on atheroma using (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/computed tomography (CT) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). METHODS: Atherosclerotic plaques were induced in the aorta of 15 New Zealand white rabbits by a combination of a hyperlipidemic diet and 2 balloon endothelial denudations. Nine rabbits continued the same diet, whereas 6 rabbits received pioglitazone (10 mg/kg orally) in addition to the diet. Twelve animals underwent (18)F-FDG-PET/CT, and 15 animals underwent DCE-MRI at baseline, 1 month, and 3 months after treatment initiation. Concomitantly, serum metabolic parameters were monitored. After imaging was completed, aortic histologic analysis and correlation analysis were performed. RESULTS: The (18)F-FDG-PET/CT imaging detected an increase in average standardized uptake value in the control group (p < 0.01), indicating progressive inflammation, whereas stable standardized uptake values were observed in the treatment group, indicating no progression. The DCE-MRI analysis detected a significant decrease in the area under the curve for the pioglitazone group (p < 0.01). Immunohistologic examination of the aortas demonstrated a significant decrease in macrophage and oxidized phospholipid immunoreactivity in the pioglitazone group (p = 0.04 and p = 0.01, respectively) with respect to control animals, underlining the imaging results. Serum metabolic parameters showed no difference between groups. Strong positive correlations between standardized uptake value and macrophage density and between area under the curve and neovessels were detected (r(2) = 0.86 and p < 0.0001, and r(2) = 0.66 and p = 0.004, respectively). CONCLUSIONS: Both (18)F-FDG-PET/CT and DCE-MRI demonstrate noninvasively the anti-inflammatory effects of pioglitazone on atheroma. Both imaging methods seem suited to monitor inflammation in atherosclerosis
— id: 139928, year: 2011, vol: 4, page: 1100, stat: Journal Article,

Globular warming: how fat gets to the furnace
Williams, Kevin Jon; Fisher, Edward A
2011 Feb;17(2):157-159, Nature medicine
— id: 133321, year: 2011, vol: 17, page: 157, stat: Journal Article,

A2A adenosine receptor stimulation decreases foam cell formation by enhancing ABCA1-dependent cholesterol efflux
Bingham, Taiese Crystal; Fisher, Edward A; Parathath, Saj; Reiss, Allison B; Chan, Edwin S; Cronstein, Bruce N
2010 Apr;87(4):683-690, Journal of leukocyte biology
Immune and inflammatory cells play a critical role in the pathogenesis of atherosclerotic plaques. We have demonstrated that A2ARs inhibit foam cell formation and stimulate production of ABCA1, the primary transporter of lipoproteins. We asked whether the effects of A2ARs on foam cell formation in vitro are mediated by transporters involved in reverse cholesterol transport, ABCA1 and ABCG1. Foam cells were generated from THP-1 cells by incubation with 100 nM PMA for 2 days and incubated with acLDL (50 mug/mL) plus IFN-gamma (500 U/mL) +/- A2AR agonist CGS-21680 (1 muM). Radiolabeled cholesterol (0.2 muCi/ml) was added to cells, and efflux was measured using a liquid scintillation counter. Lentiviral siRNA infection markedly reduces ABCA1 or ABCG1 mRNA in THP-1 cells. Despite diminished ABCG1 expression (KD), CGS-21680 inhibits foam cell formation (81+5% inhibition; P<0.0001 vs. IFN-gamma alone; n=3) but has no effect on foam cell formation in ABCA1 KD cells (5+3% inhibition; P<0.85 vs. IFN-gamma alone; n=3). The A2A agonist increases apoA-I-mediated cholesterol efflux nearly twofold in THP-1-derived macrophages (from 9.5% to 17.5+2.5% [3H]-cholesterol efflux; P<0.0090 vs. control; n=3) but not in ABCA1 KD cells. Activation of Epac, a signaling molecule downstream of the A2AR, increased ABCA1 (23+5%; P<0.0007 vs. control; n=3) and phospho-ABCA1 (13+5%; P<0.0003 vs. control; n=3) protein. These results demonstrate that A2AR occupancy diminishes foam cell formation by stimulating increased reverse cholesterol transport via ABCA1
— id: 108919, year: 2010, vol: 87, page: 683, stat: Journal Article,

RGD peptide functionalized and reconstituted high-density lipoprotein nanoparticles as a versatile and multimodal tumor targeting molecular imaging probe
Chen, W; Jarzyna, PA; van Tilborg, GAF; Nguyen, VA; Cormode, DP; Klink, A; Griffioen, AW; Randolph, GJ; Fisher, EA; Mulder, WJM; Fayad, ZA
2010 JUN ;24(6):1689-1699, FASEB journal
High density lipoprotein (HDL), an endogenous nanoparticle, transports fat throughout the body and is capable of transferring cholesterol from atheroma in the vessel wall to the liver. In the present study, we utilized HDL as a multimodal nanoparticle platform for tumor targeting and imaging via nonspecific accumulation and specific binding to angiogenically activated blood vessels. We reconstituted HDL (rHDL) with amphiphilic gadolinium chelates and fluorescent dyes. To target angiogenic endothelial cells, rHDL was functionalized with alpha v beta 3-integrin-specific RGD peptides (rHDL-RGD). Nonspecific RAD peptides were conjugated to rHDL nanoparticles as a control (rHDL-RAD). It was observed in vitro that all 3 nanoparticles were phagocytosed by macrophages, while alpha v beta 3-integrin-specific rHDL-RGD nanoparticles were preferentially taken up by endothelial cells. The uptake of nanoparticles in mouse tumors was evaluated in vivo using near infrared (NIR) and MR imaging. All nanoparticles accumulated in tumors but with very different accumulation/binding kinetics as observed by NIR imaging. Moreover, confocal microscopy revealed rHDL-RGD to be associated with tumor endothelial cells, while rHDL and rHDL-RAD nanoparticles were mainly found in the interstitial space. This study demonstrates the ability to reroute HDL from its natural targets to tumor blood vessels and its potential for multimodal imaging of tumor-associated processes.-Chen, W., Jarzyna, P. A., van Tilborg, G. A. F., Nguyen, V. A., Cormode, D. P., Klink, A., Griffioen, A. W., Randolph, G. J., Fisher, E. A., Mulder, W. J. M., Fayad, Z. A. RGD peptide functionalized and reconstituted high-density lipoprotein nanoparticles as a versatile and multimodal tumor targeting molecular imaging probe. FASEB J. 24, 1689-1699 (2010). www.fasebj.org
— id: 110153, year: 2010, vol: 24, page: 1689, stat: Journal Article,

Atherosclerotic plaque composition: analysis with multicolor CT and targeted gold nanoparticles
Cormode, David P; Roessl, Ewald; Thran, Axel; Skajaa, Torjus; Gordon, Ronald E; Schlomka, Jens-Peter; Fuster, Valentin; Fisher, Edward A; Mulder, Willem J M; Proksa, Roland; Fayad, Zahi A
2010 Sep;256(3):774-782, Radiology
PURPOSE: To investigate the potential of spectral computed tomography (CT) (popularly referred to as multicolor CT), used in combination with a gold high-density lipoprotein nanoparticle contrast agent (Au-HDL), for characterization of macrophage burden, calcification, and stenosis of atherosclerotic plaques. MATERIALS AND METHODS: The local animal care committee approved all animal experiments. A preclinical spectral CT system in which incident x-rays are divided into six different energy bins was used for multicolor imaging. Au-HDL, an iodine-based contrast agent, and calcium phosphate were imaged in a variety of phantoms. Apolipoprotein E knockout (apo E-KO) mice were used as the model for atherosclerosis. Gold nanoparticles targeted to atherosclerosis (Au-HDL) were intravenously injected at a dose of 500 mg per kilogram of body weight. Iodine-based contrast material was injected 24 hours later, after which the mice were imaged. Wild-type mice were used as controls. Macrophage targeting by Au-HDL was further evaluated by using transmission electron microscopy and confocal microscopy of aorta sections. RESULTS: Multicolor CT enabled differentiation of Au-HDL, iodine-based contrast material, and calcium phosphate in the phantoms. Accumulations of Au-HDL were detected in the aortas of the apo E-KO mice, while the iodine-based contrast agent and the calcium-rich tissue could also be detected and thus facilitated visualization of the vasculature and bones (skeleton), respectively, during a single scanning examination. Microscopy revealed Au-HDL to be primarily localized in the macrophages on the aorta sections; hence, the multicolor CT images provided information about the macrophage burden. CONCLUSION: Spectral CT used with carefully chosen contrast agents may yield valuable information about atherosclerotic plaque composition
— id: 138020, year: 2010, vol: 256, page: 774, stat: Journal Article,

LXR promotes the maximal egress of monocyte-derived cells from mouse aortic plaques during atherosclerosis regression
Feig, Jonathan E; Pineda-Torra, Ines; Sanson, Marie; Bradley, Michelle N; Vengrenyuk, Yuliya; Bogunovic, Dusan; Gautier, Emmanuel L; Rubinstein, Daniel; Hong, Cynthia; Liu, Jianhua; Wu, Chaowei; van Rooijen, Nico; Bhardwaj, Nina; Garabedian, Michael; Tontonoz, Peter; Fisher, Edward A
2010 Dec 1;120(12):4415-4424, Journal of clinical investigation
We have previously shown that mouse atherosclerosis regression involves monocyte-derived (CD68+) cell emigration from plaques and is dependent on the chemokine receptor CCR7. Concurrent with regression, mRNA levels of the gene encoding LXRalpha are increased in plaque CD68+ cells, suggestive of a functional relationship between LXR and CCR7. To extend these results, atherosclerotic Apoe-/- mice sufficient or deficient in CCR7 were treated with an LXR agonist, resulting in a CCR7-dependent decrease in plaque CD68+ cells. To test the requirement for LXR for CCR7-dependent regression, we transplanted aortic arches from atherosclerotic Apoe-/- mice, or from Apoe-/- mice with BM deficiency of LXRalpha or LXRbeta, into WT recipients. Plaques from both LXRalpha and LXRbeta-deficient Apoe-/- mice exhibited impaired regression. In addition, the CD68+ cells displayed reduced emigration and CCR7 expression. Using an immature DC line, we found that LXR agonist treatment increased Ccr7 mRNA levels. This increase was blunted when LXRalpha and LXRbeta levels were reduced by siRNAs. Moreover, LXR agonist treatment of primary human immature DCs resulted in functionally significant upregulation of CCR7. We conclude that LXR is required for maximal effects on plaque CD68+ cell expression of CCR7 and monocyte-derived cell egress during atherosclerosis regression in mice
— id: 119227, year: 2010, vol: 120, page: 4415, stat: Journal Article,

Focus on obesity
Fisher, Edward A
2010 Feb;30(2):135-135, Arteriosclerosis, thrombosis, & vascular biology
— id: 134964, year: 2010, vol: 30, page: 135, stat: Journal Article,

GPIHBP1: lipoprotein lipase's ticket to ride
Fisher, Edward A
2010 Jul 4;12(1):1-2, Cell metabolism
The mechanism of lipoprotein lipase (LPL) transport from muscle and fat cells to the luminal (apical) surface of capillaries, where it hydrolyses lipoprotein triglycerides, has remained undefined. In this issue, Davies et al. (2010) report that GPIHBP1 is required for LPL transcytosis from the basolateral to apical capillary endothelial surface
— id: 110878, year: 2010, vol: 12, page: 1, stat: Journal Article,

The heart of drug discovery
Fisher, Edward A
2010 Jul;16(7):745-745, Nature medicine
— id: 110697, year: 2010, vol: 16, page: 745, stat: Journal Article,

Multimodal clinical imaging to longitudinally assess a nanomedical anti-inflammatory treatment in experimental atherosclerosis
Lobatto, Mark E; Fayad, Zahi A; Silvera, Stephane; Vucic, Esad; Calcagno, Claudia; Mani, Venkatesh; Dickson, Stephen D; Nicolay, Klaas; Banciu, Manuela; Schiffelers, Raymond M; Metselaar, Josbert M; van Bloois, Louis; Wu, Hai-Shan; Fallon, John T; Rudd, James H; Fuster, Valentin; Fisher, Edward A; Storm, Gert; Mulder, Willem J M
2010 Dec 6;7(6):2020-2029, Molecular pharmaceutics
Atherosclerosis is an inflammatory disease causing great morbidity and mortality in the Western world. To increase the anti-inflammatory action and decrease adverse effects of glucocorticoids (PLP), a nanomedicinal liposomal formulation of this drug (L-PLP) was developed and intravenously applied at a dose of 15 mg/kg PLP to a rabbit model of atherosclerosis. Since atherosclerosis is a systemic disease, emerging imaging modalities for assessing atherosclerotic plaque are being developed. (18)F-Fluoro-deoxy-glucose positron emission tomography and dynamic contrast enhanced magnetic resonance imaging, methods commonly used in oncology, were applied to longitudinally assess therapeutic efficacy. Significant anti-inflammatory effects were observed as early as 2 days that lasted up to at least 7 days after administration of a single dose of L-PLP. No significant changes were found for the free PLP treated animals. These findings were corroborated by immunohistochemical analysis of macrophage density in the vessel wall. In conclusion, this study evaluates a powerful two-pronged strategy for efficient treatment of atherosclerosis that includes nanomedical therapy of atherosclerotic plaques and the application of noninvasive and clinically approved imaging techniques to monitor delivery and therapeutic responses. Importantly, we demonstrate unprecedented rapid anti-inflammatory effects in atherosclerotic lesions after the nanomedical therapy
— id: 134419, year: 2010, vol: 7, page: 2020, stat: Journal Article,

South Asians and risk of cardiovascular disease: current insights and trends
Mangalmurti, Sandeep S; Paley, Ari; Gany, Francesca; Fisher, Edward A; Hochman, Judith S
2010 Autumn;20(4):474-478, Ethnicity & disease
Patients from the Indian subcontinent have a distinct cardiovascular risk profile with profound health consequences. South Asians tend to develop more severe coronary artery disease at a younger age, and may also suffer from earlier myocardial infarction and heart failure. The genesis of this risk is multi-factorial. One important culprit is increased insulin resistance, possibly due to recently identified genetic polymorphisms. Another possible explanation is subclinical inflammation and a prothrombotic environment, as evidenced by increased levels of homocysteine, plasminogen activator inhibitor-1, and fibrinogen. The lipid profile of South Asians may play a role, as this population is known to have elevated levels of lipoprotein (a), as well as lower levels of HDL. In addition, this HDL may be dysfunctional, as this population may have a higher prevalence of low levels of HDL2b, as well as an increased preponderance of smaller HDL. Current guidelines for primary and secondary prevention have not reflected our growing insight into the unique characteristics of the South Asian population, and may need to evolve to reflect our knowledge
— id: 125449, year: 2010, vol: 20, page: 474, stat: Journal Article,

Rat ES-4 Is a Major Neutral Cholesteryl Ester Hydrolase and Modulates Cholesterol Pools in Hepatocytes and Alters Lipoprotein Profiles in Vivo
Parathath, Saj; Andero, Ursula; Blachford, Courtney; Darvari, Maria I.; Ghosh, Snigdha; Rothblat, George H.; Harrison, Earl H.; Fisher, Edward A.
2010 NOV ;30(11):E289-E289, Arteriosclerosis, thrombosis, & vascular biology
— id: 117308, year: 2010, vol: 30, page: E289, stat: Journal Article,

Diabetes Mellitus Inhibits Favorable Changes in Macrophage Content and Phenotype During Atherosclerotic Plaque Regression in Mice
Parathath, Saj; Grauer, Lisa; Sanson, Marie; Huang, Li-Shing; Goldberg, Ira J.; Fisher, Edward A.
2010 NOV ;30(11):E186-E186, Arteriosclerosis, thrombosis, & vascular biology
— id: 117304, year: 2010, vol: 30, page: E186, stat: Journal Article,

The Presence of Hypoxia in Murine Atherosclerotic Plaques and Its Adverse Effects on Macrophage Lipid Metabolism
Parathath, Saj; Mick, Stephanie L.; Feig, Jonathan E.; Lisa, Grauer; Joaquin, Victor; Gassmann, Max; Gardner, Lawrence B.; Fisher, Edward A.
2010 NOV ;30(11):E253-E253, Arteriosclerosis, thrombosis, & vascular biology
— id: 117307, year: 2010, vol: 30, page: E253, stat: Journal Article,

Moderate kidney disease inhibits atherosclerosis regression
Ponda, Manish P; Barash, Irina; Feig, Jonathan E; Fisher, Edward A; Skolnik, Edward Y
2010 May;210(1):57-62, Atherosclerosis
Chronic kidney disease (CKD) accelerates cardiovascular disease. The mechanisms that explain this independent, excess risk associated with CKD have not been fully elucidated. OBJECTIVES: We propose that impaired regression of atherosclerosis in renal disease represents a novel risk factor for the heightened morbidity and mortality and resistance to treatment observed in patients with CKD. METHODS AND RESULTS: Using a transplant model to study atherosclerosis regression, we transplanted atheromatous aortic segments generated in Apolipoprotein E knock-out (ApoE(-/-)) mice, into either control or moderately uremic, normolipidemic, wild-type mice. In non-uremic mice, lesions regressed 55%, whereas lesions in uremic mice increased in size by 17% (p<0.01 for control vs. uremic). The lesions in uremic mice were also characterized by a greater presence of macrophages (36,300 microm(2) vs. 12,600 microm(2), p<0.01). This finding was despite upregulation of chemokine receptor 7 (CCR7), normally a migration factor, in uremic lesion macrophages. Gene expression analysis of lesion macrophages showed relative down-regulation of serum response factor (SRF) target genes in the uremic group, consistent with impaired CCR7 signaling. CONCLUSION: Moderate kidney disease inhibits regression of atherosclerosis in a mouse transplant model. This inhibition may be a result of impaired CCR7 signaling
— id: 109717, year: 2010, vol: 210, page: 57, stat: Journal Article,

Mir-33 Coordinates Genes Regulating Cholesterol Homeostasis
Rayner, Katey J.; Suarez, Yajaira; Davalos, Alberto; Parathath, Saj; Fitzgerald, Michael L.; Tamehiro, Norimasa; Fisher, Edward A.; Moore, Kathryn J.; Fernandez-Hernando, Carlos
2010 NOV ;30(11):E191-E191, Arteriosclerosis, thrombosis, & vascular biology
— id: 117305, year: 2010, vol: 30, page: E191, stat: Journal Article,

MiR-33 contributes to the regulation of cholesterol homeostasis
Rayner, Katey J; Suarez, Yajaira; Davalos, Alberto; Parathath, Saj; Fitzgerald, Michael L; Tamehiro, Norimasa; Fisher, Edward A; Moore, Kathryn J; Fernandez-Hernando, Carlos
2010 Jun 18;328(5985):1570-1573, Science
Cholesterol metabolism is tightly regulated at the cellular level. Here we show that miR-33, an intronic microRNA (miRNA) located within the gene encoding sterol-regulatory element-binding factor-2 (SREBF-2), a transcriptional regulator of cholesterol synthesis, modulates the expression of genes involved in cellular cholesterol transport. In mouse and human cells, miR-33 inhibits the expression of the adenosine triphosphate-binding cassette (ABC) transporter, ABCA1, thereby attenuating cholesterol efflux to apolipoprotein A1. In mouse macrophages, miR-33 also targets ABCG1, reducing cholesterol efflux to nascent high-density lipoprotein (HDL). Lentiviral delivery of miR-33 to mice represses ABCA1 expression in the liver, reducing circulating HDL levels. Conversely, silencing of miR-33 in vivo increases hepatic expression of ABCA1 and plasma HDL levels. Thus, miR-33 appears to regulate both HDL biogenesis in the liver and cellular cholesterol efflux
— id: 138135, year: 2010, vol: 328, page: 1570, stat: Journal Article,

High-density lipoprotein-based contrast agents for multimodal imaging of atherosclerosis
Skajaa, Torjus; Cormode, David P; Falk, Erling; Mulder, Willem J M; Fisher, Edward A; Fayad, Zahi A
2010 Feb;30(2):169-176, Arteriosclerosis, thrombosis, & vascular biology
Lipoproteins, natural nanoparticles, have a well-recognized biological role and are highly suitable as a platform for delivering imaging agents. The ease with which both the exterior and interior of the particles can be modified permits the creation of multifunctional nanoparticles for imaging as well as the delivery of therapeutics. Importantly, their endogenous nature may make them biocompatible and biodegradable and allows them to avoid the recognition of the reticuloendothelial system. In particular, high-density lipoproteins (HDL) are of interest, because of their small size they can easily cross the endothelium and penetrate the underlying tissue. We summarize here the progress in establishing HDL as a vector for delivering a variety of diagnostically active materials to vulnerable atherosclerotic plaques in mouse models of atherosclerosis. By loading various types of image-enhancing compounds into either the core or surface of HDL, they can be visualized by different imaging modalities (MRI, CT, optical). By rerouting of HDL away from plaque macrophages, imaging of biological processes in diseases besides atherosclerosis may also be achieved
— id: 134965, year: 2010, vol: 30, page: 169, stat: Journal Article,

Quantum Dot and Cy5.5 Labeled Nanoparticles to Investigate Lipoprotein Biointeractions via Forster Resonance Energy Transfer
Skajaa, Torjus; Zhao, Yiming; van den Heuvel, Dave J.; Gerritsen, Hans C.; Cormode, David P.; Koole, Rolf; van Schooneveld, Matti M.; Post, Jan Andries; Fisher, Edward A.; Fayad, Zahi A.; Donega, Celso de Mello; Meijerink, Andries; Mulder, Willem J. M.
2010 DEC ;10(12):5131-5138, Nano letters
The study of lipoproteins, natural nanoparticles comprised of lipids and apolipoproteins that transport fats throughout the body, is of key importance to better understand, treat, and prevent cardiovascular disease. In the current study, we have developed a lipoprotein-based nanoparticle that consists of a quantum dot (QD) core and Cy5.5 labeled lipidic coating. The methodology allows Judicious tuning of the QD/Cy5.5 ratio, which enabled us to optimize Forster resonance energy transfer (FRET) between the QD core and the Cy5.5-labeled coating. This phenomenon allowed us to study lipoprotein lipoprotein interactions, lipid exchange dynamics, and the influence of apolipoproteins on these processes. Moreover, we were able to study HDL-cell interactions and exploit FRET to visualize HDL association with live macrophage cells
— id: 116233, year: 2010, vol: 10, page: 5131, stat: Journal Article,

A Reversible Macrophage-Like Phenotype of Vascular Smooth Muscle Cell: Implications in Atherosclerosis
Vengrenyuk, Yuliya; Long, Xiaochun; Blachford, Courtney; Miano, Joseph M.; Fisher, Edward A.
2010 NOV ;30(11):E215-E215, Arteriosclerosis, thrombosis, & vascular biology
— id: 117306, year: 2010, vol: 30, page: E215, stat: Journal Article,

Fish oil for the treatment of cardiovascular disease
Weitz, Daniel; Weintraub, Howard; Fisher, Edward; Schwartzbard, Arthur Z
2010 Sep-Oct;18(5):258-263, Cardiology in review
Omega-3 fatty acids, which are found abundantly in fish oil, are increasingly being used in the management of cardiovascular disease. It is clear that fish oil, in clinically used doses (typically 4 g/d of eicosapentaenoic acid and docosahexaenoic acid) reduce high triglycerides. However, the role of omega-3 fatty acids in reducing mortality, sudden death, arrhythmias, myocardial infarction, and heart failure has not yet been established. This review will focus on the current clinical uses of fish oil and provide an update on their effects on triglycerides, coronary artery disease, heart failure, and arrhythmia. We will explore the dietary sources of fish oil as compared with drug therapy, and discuss the use of fish oil products in combination with other commonly used lipid-lowering agents. We will examine the underlying mechanism of fish oil's action on triglyceride reduction, plaque stability, and effect in diabetes, and review the newly discovered anti-inflammatory effects of fish oil. Finally, we will examine the limitations of current data and suggest recommendations for fish oil use
— id: 111598, year: 2010, vol: 18, page: 258, stat: Journal Article,

Atherosclerosis and Matrix Metalloproteinases: Experimental Molecular MR Imaging in Vivo
Amirbekian, V; Aguinaldo, JGS; Amirbekian, S; Hyafil, F; Vucic, E; Sirol, M; Weinreb, DB; Le Greneur, S; Lancelot, E; Corot, C; Fisher, EA; Galis, ZS; Fayad, ZA
2009 MAY ;251(2):429-438, Radiology
Purpose: To evaluate the capability of P947, a magnetic resonance (MR) imaging contrast agent that molecularly targets matrix metalloproteinases (MMPs), to aid detection and imaging of MMPs in atherosclerotic lesions in vivo; its specificity compared with that of P1135; expression and distribution of MMPs in atherosclerotic vessels; and in vivo distribution and molecular localization of fluorescent europium (Eu) P947. Materials and Methods: The Animal Care and Use Committee approved all experiments. P947 was synthesized by attaching a gadolinium chelate (1,4,7,10-tetraazacyclododecane- N, N', N', N'''-tetraacetic acid) to a peptide that specifically binds MMPs. Scrambled form of P947 (P1135) was synthesized by replacing the targeting moiety of P947 with a scrambled peptide lacking the ability to bind MMPs. P947, P1135, and gadoterate meglumine were injected into atherosclerotic apolipoprotein E-deficient and wild-type mice. The aortic MR imaging enhancement produced by the contrast agents was measured at different times and was compared by using one-way analysis of variance. MMP expression was investigated in the aortas by using MMP immunostaining and in situ MMP zymography. A fluorescent form of P947 (Eu-P947) was synthesized to compare the in vivo distribution of the contrast agent (Eu-P947) with specific MMP immunofluorescent staining. Results: MMP-targeted P947 facilitated a 93% increase (P < .001) in MR image signal intensity (contrast-to-noise ratio [CNR], 17.7 compared with 7.7; P < .001) of atherosclerotic lesions in vivo. Nontargeted P1135 (scrambled P947) provided 33% MR image enhancement (CNR, 10.8), whereas gadoterate meglumine provided 5% (CNR, 6.9). Confocal laser scanning microscopy demonstrated colocalization between fluorescent Eu-P947 and MMPs in atherosclerotic plaques. Eu-P947 was particularly present in the fibrous cap region of plaques. Conclusion: P947 improved MR imaging for atherosclerosis through MMP- specific targeting. The results were validated and provide support for further assessment of P947 as a potential tool for the identification of unstable atherosclerosis
— id: 98839, year: 2009, vol: 251, page: 429, stat: Journal Article,

Cu/Zn-Superoxide Dismutase Enzyme Prevents Hepatic Apolipoprotein B100 Degradation Induced by Fish Oil
Andreo, U; Elkind, J; Blachford, C; Cederbaum, AI; Fisher, EA
2009 JUL ;29(7):E37-E37, Arteriosclerosis, thrombosis, & vascular biology
— id: 101262, year: 2009, vol: 29, page: E37, stat: Journal Article,

Cholesterol 27-hydroxylase but not apolipoprotein e contributes to A2A adenosine receptor enhanced reverse cholesterol transport
Bingham T.C.; Parahath S.; Reiss A.; Chan E.S.L.; Fisher E.; Cronstein B.N.
2009 ;60:433-433, Arthritis & rheumatism
Purpose: Unlike other DMARDs methotrexate diminishes the risk of Atherosclerotic Cardiovascular Disease (ASCVD) in patients with Rheumatoid Arthritis and adenosine, acting at adenosine A2A receptors, has been shown to mediate the anti-inflammatory effects of methotrexate. Adenosine inhibits the first step in formation of atherosclerotic plaque, foam cell formation in macrophages and this effect appears to be mediated by enhanced expression of cholesterol 27-hydroxylase, an enzyme involved in reverse cholesterol transport. We therefore asked whether the effect of adenosine A2A receptors on foam cell formation in vitro are mediated by apoE or 27-hydroxylase (27OH'ase), proteins involved in reverse cholesterol transport. Method: THP-1 cells, a human monocytoid cell line, were infected with lentiviral vectors expressing siRNA for either apoE or 27OH'ase or scrambled RNA and infected cell lines were selected by incubation with puromycin. Foam cell formation was induced in THP-1 cells by incubation with interferon- (500U/ml) and % foam cells enumerated in 5 high power fields. 3H-Cholesterol efflux was measured after loading with label. Results: Specific lentiviral siRNA infection markedly reduces apoE (p< 0.0001, apoE siRNA vs. control, n=3) or 27OH'ase mRNA (p< 0.0001, 27-hydroxylase siRNA vs. control, n=3) and protein (p< 0.0107, 27-hydroxylase siRNA vs. control n= 3) in THP-1 cells. Despite diminished apoE expression CGS-21680 (1muM), an adenosine A2A receptor agonist, inhibits IFN-induced foam cell formation (p< 0.0002, IFN CGS vs. IFN alone, n= 4) but has no effect on foam cell formation in 27OH'ase KD cells. CGS21680 increases cholesterol efflux in wild type and apoE1 KD cells (from 9.5% to 17.5+2.5% and from 10.0+2% to 17.5 +2%, respectively) but not 27OH'ase KD cells. Conclusion: Adenosine A2A receptor-mediated increases in reverse cholesterol transport leading to diminished foam cell formation explains the anti-atherosclerotic effects of methotrexate
— id: 130321, year: 2009, vol: 60, page: 433, stat: Journal Article,

High-relaxivity gadolinium-modified high-density lipoproteins as magnetic resonance imaging contrast agents
Briley-Saebo, Karen C; Geninatti-Crich, Simonetta; Cormode, David P; Barazza, Alessandra; Mulder, Willem J M; Chen, Wei; Giovenzana, Giovanni B; Fisher, Edward A; Aime, Silvio; Fayad, Zahi A
2009 May 7;113(18):6283-6289, Journal of physical chemistry. B. Condensed matter, materials, surfaces, interfaces & biophysical
There is an ongoing desire to produce high-relaxivity, Gd-based magnetic resonance imaging (MRI) contrast agents. These may allow for lower doses to be used, which is especially important in view of the current safety concerns surrounding Gd in patients. Here we report the synthesis of a high-relaxivity MRI contrast agent, by incorporating Gd-chelating lipids that coordinate two water molecules into high-density lipoprotein (q = 2 HDL). We compared the properties of q = 2 HDL with those of an analogous HDL particle labeled with Gd-chelating lipids that coordinate only one water molecule (q = 1 HDL). We found that the q = 2 HDL possessed an elevated r(1) of 41 mM(-1) s(-1) compared to 9 mM(-1) s(-1) for q = 1 HDL at 20 MHz, but the q = 2 HDL exhibited high R(2)* values at high fields, precluding imaging above 128 MHz. While carrying out this investigation we observed that enlarged, disrupted particles were formed when the synthesis was carried out above the lipid critical micelle concentration (cmc), indicating the importance of synthesis below the cmc when modifying lipoproteins in this manner. The high relaxivity of q = 2 HDL means it will be an efficacious contrast agent for future MR imaging studies
— id: 135215, year: 2009, vol: 113, page: 6283, stat: Journal Article,

Genetic variation in genes of the fatty acid synthesis pathway and breast cancer risk
Campa, Daniele; McKay, James; Sinilnikova, Olga; Husing, Anika; Vogel, Ulla; Hansen, Rikke Dalgaard; Overvad, Kim; Witt, Petra Mariann; Clavel-Chapelon, Francoise; Boutron-Ruault, Marie-Christine; Chajes, Veronique; Rohrmann, Sabine; Chang-Claude, Jenny; Boeing, Heiner; Fisher, Eva; Trichopoulou, Antonia; Trichopoulos, Dimitrios; Palli, Domenico; Villarini, Anna; Sacerdote, Carlotta; Mattiello, Amalia; Tumino, Rosario; Peeters, Petra H M; van Gils, Carla H; Bas Bueno-de-Mesquita, H; Lund, Eiliv; Chirlaque, Maria Dolores; Sala, Nuria; Suarez, Laudina Rodriguez; Barricarte, Aurelio; Dorronsoro, Miren; Sanchez, Maria-Jose; Lenner, Per; Hallmans, Goran; Tsilidis, Kostas; Bingham, Sheila; Khaw, Kay-Tee; Gallo, Valentina; Norat, Teresa; Riboli, Elio; Rinaldi, Sabina; Lenoir, Gilbert; Tavtigian, Sean V; Canzian, Federico; Kaaks, Rudolf
2009 Dec;118(3):565-574, Breast cancer research & treatment
Fatty acid synthase (FAS) is the major enzyme of lipogenesis. It catalyzes the NADPH-dependent condensation of acetyl-CoA and malonyl-CoA to produce palmitic acid. Transcription of the FAS gene is controlled synergistically by the transcription factors ChREBP (carbohydrate response element-binding protein), which is induced by glucose, and SREBP-1 (sterol response element-binding protein-1), which is stimulated by insulin through the PI3K/Akt signal transduction pathway. We investigated whether the genetic variability of the genes encoding for ChREBP, SREBP and FAS (respectively, MLXIPL, SREBF1 and FASN) is related to breast cancer risk and body-mass index (BMI) by studying 1,294 breast cancer cases and 2,452 controls from the European Prospective Investigation on Cancer (EPIC). We resequenced the FAS gene and combined information of SNPs found by resequencing and SNPs from public databases. Using a tagging approach and selecting 20 SNPs, we covered all the common genetic variation of these genes. In this study we were not able to find any statistically significant association between the SNPs in the FAS, ChREBP and SREPB-1 genes and an increased risk of breast cancer overall and by subgroups of age, menopausal status, hormone replacement therapy (HRT) use or BMI. On the other hand, we found that two SNPs in FASN were associated with BMI
— id: 143958, year: 2009, vol: 118, page: 565, stat: Journal Article,

Molecular Imaging in Atherosclerosis, Thrombosis, and Vascular Inflammation
Choudhury, RP; Fisher, EA
2009 JUL ;29(7):983-991, Arteriosclerosis, thrombosis, & vascular biology
Appreciation of the molecular and cellular processes of atherosclerosis, thrombosis, and vascular inflammation has identified new targets for imaging. The common goals of molecular imaging approaches are to accelerate and refine diagnosis, provide insights that reveal disease diversity, guide specific therapies, and monitor the effects of those therapies. Here we undertake a comparative analysis of imaging modalities that have been used in this disease area. We consider the elements of contrast agents, emphasizing how an understanding of the biology of atherosclerosis and its complications can inform optimal design. We address the potential and limitations of current contrast approaches in respect of translation to clinically usable agents and speculate on future applications. (Arterioscler Thromb Vasc Biol. 2009; 29: 983-991.)
— id: 101259, year: 2009, vol: 29, page: 983, stat: Journal Article,

Comparison of Synthetic High Density Lipoprotein (HDL) Contrast Agents for MR Imaging of Atherosclerosis
Cormode, DP; Chandrasekar, R; Delshad, A; Briley-Saebo, KC; Calcagno, C; Barazza, A; Mulder, WJM; Fisher, EA; Fayad, ZA
2009 MAY ;20(5):937-943, Bioconjugate chemistry
Determining arterial macrophage expression is an important goal in the molecular imaging of atherosclerosis. Here, we compare the efficacy of two synthetic, high density lipoprotein (HDL) based contrast agents for magnetic resonance imaging (MRI) of macrophage burden. Each form of HDL was labeled with gadolinium and rhodamine to allow MRI and fluorescence microscopy. Either the 37 or 18 amino acid peptide replaced the apolipoprotein A-I in these agents, which were termed 37pA-Gd or 18A-Gd. The diameters of 37pA-Gd and 18A-Gd are 7.6 and 8.0 nm, respectively, while the longitudinal relaxivities are 9.8 and 10.0 (mM s)(-1). 37pA has better lipid binding properties. In vitro tests with J774A.1 macrophages proved the particles possessed the functionality of HDL by eliciting cholesterol efflux and were taken up in a receptor-like fashion by the cells. Both agents produced enhancements in atherosclerotic plaques of apolipoprotein E knockout mice of similar to 90% (n = 7 per agent) and are macrophage specific as evidenced by confocal microscopy on aortic sections. The half-lives of 37pA-Gd and 18A-Gd are 2.6 and 2.1 h, respectively. Despite the more favorable lipid interactions of 37pA, both agents gave similar, excellent contrast for the detection of atherosclerotic macrophages using MRI
— id: 99306, year: 2009, vol: 20, page: 937, stat: Journal Article,

HDL as a contrast agent for medical imaging
Cormode, DP; Frias, JC; Ma, YQ; Chen, W; Skajaa, T; Briley-Saebo, K; Barazza, A; Williams, KJ; Mulder, WJM; Fayad, ZA; Fisher, EA
2009 AUG ;4(4):493-500, Clinical Lipidology
Contrast-enhanced MRI of atherosclerosis can provide valuable additional information on a patient's disease state. As a result of the interactions of HDL with atherosclerotic plaque and the flexibility of its reconstitution, it is a versatile candidate for the delivery of contrast-generating materials to this pathogenic lesion. We herein discuss the reports of HDL modified with gadolinium to act as an MRI contrast agent for atherosclerosis. Furthermore, HDL has been modified with fluorophores and nanocrystals, allowing it to act as a contrast agent for fluorescent imaging techniques and for computed tomography. Such modified HDL has been found to be macrophage specific, and, therefore, can provide macrophage density information via noninvasive MRI. As such, modified HDL is currently a valuable contrast agent for probing preclinical atherosclerosis. Future developments may allow the application of this particle to further diseases and pathological or physiological processes in both preclinical models as well as in patients
— id: 101611, year: 2009, vol: 4, page: 493, stat: Journal Article,

Atherosclerosis Regression Promoted by an LXR Agonist is Dependent on the Chemokine Receptor CCR7 and Requires Both LXR alpha and LXR beta: Insights into Reducing Stroke Incidence
Feig, JE; Pineda-Torra, I; Garabedian, MJ; Tontonoz, P; Fisher, EA
2009 APR ;40(4):E149-E149, Stroke
— id: 97792, year: 2009, vol: 40, page: E149, stat: Journal Article,

ApoAI Is Required for the Regression of Atherosclerosis and Is a Potent Regulator of Plaque Monocyte-Derived Emigration and Inflammatory State
Feig, JE; Shamir, R; Joaquin, V; Grauer, L; Fisher, EA
2009 JUL ;29(7):E13-E13, Arteriosclerosis, thrombosis, & vascular biology
— id: 101260, year: 2009, vol: 29, page: E13, stat: Journal Article,

The role of a murine transplantation model of atherosclerosis regression in drug discovery
Feig, Jonathan E; Quick, John S; Fisher, Edward A
2009 Mar;10(3):232-238, Current opinion in investigational drugs
Atherosclerosis is the leading cause of death worldwide. To date, the use of statins to lower LDL levels has been the major intervention used to delay or halt disease progression. These drugs have an incomplete impact on plaque burden and risk, however, as evidenced by the substantial rates of myocardial infarctions that occur in large-scale clinical trials of statins. Thus, it is hoped that by understanding the factors that lead to plaque regression, better approaches to treating atherosclerosis may be developed. A transplantation-based mouse model of atherosclerosis regression has been developed by allowing plaques to form in a model of human atherosclerosis, the apoE-deficient mouse, and then placing these plaques into recipient mice with a normolipidemic plasma environment. Under these conditions, the depletion of foam cells occurs. Interestingly, the disappearance of foam cells was primarily due to migration in a CCR7-dependent manner to regional and systemic lymph nodes after 3 days in the normolipidemic (regression) environment. Further studies using this transplant model demonstrated that liver X receptor and HDL are other factors likely to be involved in plaque regression. In conclusion, through the use of this transplant model, the process of uncovering the pathways regulating atherosclerosis regression has begun, which will ultimately lead to the identification of new therapeutic targets
— id: 99294, year: 2009, vol: 10, page: 232, stat: Journal Article,

THE CELLULAR REGULATION OF VLDL METABOLISM AND ITS RELEVANCE TO DIETARY FAT AND INSULIN RESISTANCE
Fisher, E.
2009 JUN ;10(2):-, Atherosclerosis. Supplements
— id: 126460, year: 2009, vol: 10, page: , stat: Journal Article,

National Cholesterol Month
Fisher, EA
2009 SEP ;29(9):1243-1243, Arteriosclerosis, thrombosis, & vascular biology
— id: 101946, year: 2009, vol: 29, page: 1243, stat: Journal Article,

The ever-expanding role of degradation in the regulation of apolipoprotein B metabolism
Ginsberg, HN; Fisher, EA
2009 APR ;50(4):S162-S166, Journal of lipid research
Apolipoprotein B (apoB) is the essential protein required for the assembly and secretion of chylomicrons from the small intestine and VLDLs from the liver. These lipoproteins, as well as their remnants and LDL, play key roles in the transport of dietary and endogenously synthesized lipids throughout the body. However, they can be involved in the initiation of atherosclerotic lesions in the vessel wall. Therefore, it is not surprising that the assembly of apoB-containing lipoproteins in the small intestine and liver is a highly regulated process. In particular, cotranslational and posttranslational targeting of apoB for degradation, regulated largely by the availability of the core lipids carried in the lipoprotein, by the types of dietary fatty acids consumed, and by the hormonal milieu, determines the number of chylomicrons or VLDL that are secreted. jlr In this review, we summarize both older and more recent findings on the pathways of apoB degradation, focusing on events in the liver.-Ginsberg, H. N., and E. A. Fisher. The ever-expanding role of degradation in the regulation of apolipoprotein B metabolism. J. Lipid Res. 2009. S162-S166
— id: 98096, year: 2009, vol: 50, page: S162, stat: Journal Article,

Vitamin D receptor and calcium sensing receptor polymorphisms and the risk of colorectal cancer in European populations
Jenab, Mazda; McKay, James; Bueno-de-Mesquita, Hendrik B; van Duijnhoven, Franzel J B; Ferrari, Pietro; Slimani, Nadia; Jansen, Eugene H J M; Pischon, Tobias; Rinaldi, Sabina; Tjonneland, Anne; Olsen, Anja; Overvad, Kim; Boutron-Ruault, Marie-Christine; Clavel-Chapelon, Francoise; Engel, Pierre; Kaaks, Rudolf; Linseisen, Jakob; Boeing, Heiner; Fisher, Eva; Trichopoulou, Antonia; Dilis, Vardis; Oustoglou, Erifili; Berrino, Franco; Vineis, Paolo; Mattiello, Amalia; Masala, Giovanna; Tumino, Rosario; Vrieling, Alina; van Gils, Carla H; Peeters, Petra H; Brustad, Magritt; Lund, Eiliv; Chirlaque, Maria-Dolores; Barricarte, Aurelio; Suarez, Laudina Rodriguez; Molina, Esther; Dorronsoro, Miren; Sala, Nuria; Hallmans, Goran; Palmqvist, Richard; Roddam, Andrew; Key, Timothy J; Khaw, Kay-Tee; Bingham, Sheila; Boffetta, Paolo; Autier, Philippe; Byrnes, Graham; Norat, Teresa; Riboli, Elio
2009 Sep;18(9):2485-2491, Cancer epidemiology biomarkers & prevention
Increased levels of vitamin D and calcium may play a protective role in colorectal cancer (CRC) risk. It has been suggested that these effects may be mediated by genetic variants of the vitamin D receptor (VDR) and the calcium sensing receptor (CASR). However, current epidemiologic evidence from European populations for a role of these genes in CRC risk is scarce. In addition, it is not clear whether these genes may modulate CRC risk independently or by interaction with blood vitamin D concentration and level of dietary calcium intake. A case-control study was conducted nested within the European Prospective Investigation into Cancer and Nutrition. CRC cases (1,248) were identified and matched to 1,248 control subjects. Genotyping for the VDR (BsmI: rs1544410; Fok1: rs2228570) and CASR (rs1801725) genes was done by Taqman, and serum vitamin D (25OHD) concentrations were measured. Conditional logistic regression was used to estimate the incidence rate ratio (RR). Compared with the wild-type bb, the BB genotype of the VDR BsmI polymorphism was associated with a reduced risk of CRC [RR, 0.76; 95% confidence interval (CI), 0.59-0.98). The association was observed for colon cancer (RR, 0.69; 95% CI, 0.45-0.95) but not rectal cancer (RR, 0.97; 95% CI, 0.62-1.49). The Fok1 and CASR genotypes were not associated with CRC risk in this study. No interactions were noted for any of the polymorphisms with serum 25OHD concentration or level of dietary calcium. These results confirm a role for the BsmI polymorphism of the VDR gene in CRC risk, independent of serum 25OHD concentration and dietary calcium intake
— id: 143962, year: 2009, vol: 18, page: 2485, stat: Journal Article,

Apolipoprotein-B100 Assembly and Secretion in the Human Hepatoma Cell Lines HepG2 and HUH7
Meex, SJ; Fisher, EA
2009 JUL ;29(7):E36-E36, Arteriosclerosis, thrombosis, & vascular biology
— id: 101261, year: 2009, vol: 29, page: E36, stat: Journal Article,

The Neutral Cholesteryl Ester Hydrolase Es-4 in Addition to Modulating Cholesteryl Ester Pools Within Hepatocytes Can Alter Lipoprotein Profiles in Vivo
Parathath, S; Ghosh, S; Dogan, S; Joaquin, VA; Blachford, C; Weibel, G; Rothblat, G; Harrison, EH; Fisher, EA
2009 JUL ;29(7):E106-E106, Arteriosclerosis, thrombosis, & vascular biology
— id: 101264, year: 2009, vol: 29, page: E106, stat: Journal Article,

Atherosclerotic Plaque Regression Is Impaired by Hyperglycemia
Parathath, S; Grauer, L; Yuan, CJY; Sanson, M; Blachford, C; Goldberg, IJ; Fisher, EA
2009 JUL ;29(7):E79-E79, Arteriosclerosis, thrombosis, & vascular biology
— id: 101263, year: 2009, vol: 29, page: E79, stat: Journal Article,

Brief report: increased apoptosis in advanced atherosclerotic lesions of Apoe-/- mice lacking macrophage Bcl-2
Thorp, Edward; Li, Yankun; Bao, Liping; Yao, Pin Mei; Kuriakose, George; Rong, James; Fisher, Edward A; Tabas, Ira
2009 Feb;29(2):169-172, Arteriosclerosis, thrombosis, & vascular biology
OBJECTIVE: Macrophage apoptosis plays important roles in atherosclerosis. Bcl-2 is a key cell survival molecule, but its role in macrophage apoptosis in atherosclerosis is not known. The goal herein was to determine the effect of macrophage-targeted deletion of Bcl-2 on macrophage apoptosis in atherosclerotic lesions of Apoe(-/-) mice. METHODS AND RESULTS: Bcl2(flox)-LysMCre mice were created as a model of macrophage Bcl-2 deficiency. Macrophages from these mice were more susceptible to apoptosis than those from control Bcl2(WT)-LysMCre mice. The mice were bred onto the Apoe(-/-) background and fed a Western-type diet for 4 or 10 weeks. Apoptotic cells were equally very rare in the lesions of both groups of the 4-week-diet mice, and there was no difference in lesion area. However, Bcl2(flox)-LysMCre;Apoe(-/-) plaques from the 10-week-diet protocol had a 40% to 45% increase in apoptotic cells and, in female mice, a approximately 25% increase in plaque necrosis (P<0.05) compared with Bcl2(WT)-LysMCre lesions. CONCLUSIONS: Macrophage Bcl-2 plays a protective role against macrophage apoptosis specifically in advanced atherosclerotic lesions of Apoe(-/-) mice
— id: 133658, year: 2009, vol: 29, page: 169, stat: Journal Article,

Arrhythmogenic potential of activated fibroblasts
Vasquez C.; Feig J.E.; Mohandas P.; Fisher E.A.; Morley G.E.
2009 ;6(5 SUPPL 1):S458-S458, Heart rhythm
Introduction: A critical event in the development of cardiac fibrosis is the transformation of fibroblasts into myofibroblasts. Fibroblasts isolated from healthy hearts and grown under standard tissue culture conditions express alpha-SMA and have been referred to as myofibroblasts. However, recent data suggest the in vitro transformation does not fully replicate the in vivo activation process. The purpose of this study was to investigate the potential of activated fibroblasts to contribute to an arrhythmogenic substrate through paracrine and direct coupling effects. Methods: Confluent neonatal rat myocyte monolayers were treated with media (CM) conditioned by cardiac fibroblasts isolated from ventricles of healthy (Fb) and infarcted (MI-Fb) hearts and optically mapped 16-20 hours later. To study the combined paracrine and direct coupling effect, Fb and MI-Fb were plated on top of myocyte monolayers. Results: Treatment with both Fb CM (16.6+/-0.4 cm/s) and MIFb CM (15.8+/-0.4 cm/s) significantly decreased conduction velocity (CV) compared to homocellular myocyte monolayers (Myo; 19.7+/-0.7 cm/s). Action potential duration (APD70) was significantly reduced by MI-Fb CM (143.6+/-1.7 ms) treatment compared to Myo (159.4+/-4.0 ms) and Fb CM (153.4+/-2.7 ms). In heterocellular cultures, Fb significantly decreased (17.0+/-0.5 cm/s) and MI-Fb increased (22.0+/-0.6 cm/s) average CV compared to Myo. In addition, CV was significantly faster with MI-Fb compared to Fb (p=1.95E-8). Fb (145.0+/-3.9 ms) and MIFb (131.1+/-3.7 ms) significantly reduced APD70 compared to Myo (159.4+/-4.0 ms), and APD70 was significantly shorter with MI-Fb compared to Fb (p=0.01). Analysis of Cx43 levels showed a significant upregulation of Cx43 in MI-Fb compared to Fb. Conclusions: These data demonstrate Fb exert predominantly paracrine effects while MI-Fb affect myocyte electrophysiology through a combination of paracrine and direct coupling mechanisms. Moreover, APD shortening and increased Cx43 levels in MI-Fb could contribute to the greater incidence of arrhythmias observed in fibrotic hearts. These findings may lead to the development of new anti-arrhythmic therapeutic approaches targeting the fibroblast activation process
— id: 131858, year: 2009, vol: 6, page: S458, stat: Journal Article,

The relationship between the exchange of gadolinium among lipoproteins and plasma proteins and magnetic resonance plaque imaging efficacy of reconstituted HDL
Barazza, A; Joaquin, VA; Briley-Saeboe, KC; Williams, KJ; Fayad, ZA; Fisher, EA
2008 JUN ;28(6):E127-E127, Arteriosclerosis, thrombosis, & vascular biology
— id: 86981, year: 2008, vol: 28, page: E127, stat: Journal Article,

The many intersecting pathways underlying apolipoprotein B secretion and degradation
Brodsky, JL; Fisher, EA
2008 SEP ;19(7):254-259, Trends in endocrinology & metabolism
Because the levels of secreted apolipoprotein B (apoB) directly correlate with circulating serum cholesterol levels, there is a pressing need to define how the biosynthesis of this protein is regulated. Most commonly, the concentration of a secreted, circulating protein corresponds to transcriptionally and/or translationally regulated events. By contrast, circulating apoB levels are controlled by degradative pathways in the cell that select the protein for disposal. This article summarizes recent findings on two apoB disposal pathways, endoplasmic reticulum (ER)-associated degradation and autophagy, and describes a role for post-ER degradation in the increased circulating lipid levels in insulin-resistant diabetics
— id: 89374, year: 2008, vol: 19, page: 254, stat: Journal Article,

Incorporation of an apoE-derived lipopeptide in high-density lipoprotein MRI contrast agents for enhanced imaging of macrophages in atherosclerosis
Chen, Wei; Vucic, Esad; Leupold, Eik; Mulder, Willem J M; Cormode, David P; Briley-Saebo, Karen C; Barazza, Alessandra; Fisher, Edward A; Dathe, Margitta; Fayad, Zahi A
2008 Nov-Dec;3(6):233-242, Contrast Media & Molecular Imaging
Magnetic resonance (MR) imaging is becoming a pivotal diagnostic method to identify and characterize vulnerable atherosclerotic plaques. We previously reported a reconstituted high-density lipoprotein (rHDL) nanoparticle platform enriched with Gd-based amphiphiles as a plaque-specific MR imaging contrast agent. Further modification can be accomplished by inserting targeting moieties into this platform to potentially allow for improved intraplaque macrophage uptake. Since studies have indicated that intraplaque macrophage density is directly correlated to plaque vulnerability, modification of the rHDL platform may allow for better detection of vulnerable plaques. In the current study we incorporated a carboxyfluoresceine-labeled apolipoprotein E-derived lipopeptide, P2fA2, into rHDL. The in vitro macrophage uptake and in vivo MR efficacy were demonstrated using murine J774A.1 macrophages and the apolipoprotein E knock-out (apoE(-/-)) mouse model of atherosclerosis. The in vitro studies indicated enhanced association of murine macrophages to P2fA2 enriched rHDL (rHDL-P2A2) nanoparticles, relative to rHDL, using optical techniques and MR imaging. The in vivo studies showed a more pronounced and significantly higher signal enhancement of the atherosclerotic wall 24 h after the 50 micromol Gd/kg injection of rHDL-P2A2 relative to administration of rHDL. The normalized enhancement ratio for atherosclerotic wall of rHDL-P2A2 contrast agent injection was 90%, while that of rHDL was 53% 24 h post-injection. Confocal laser scanning microscopy revealed that rHDL-P2A2 nanoparticles co-localized primarily with intraplaque macrophages. The results of the current study confirm the hypothesis that intraplaque macrophage uptake of rHDL may be enhanced by the incorporation of the P2fA2 peptide into the modified HDL particle
— id: 133612, year: 2008, vol: 3, page: 233, stat: Journal Article,

PROLONGED EXPOSURE TO HIGH FAT DIET AND HYPERLIPIDEMIA IN MICE EXACERBATES ACUTE PANCREATITIS
Clair, JMS; Joaquin, VA; Fisher, EA; Bar-Sagi, D
2008 NOV ;37(4):482-483, Pancreas
— id: 91327, year: 2008, vol: 37, page: 482, stat: Journal Article,

COLL 2-Inorganic core HDL applied for molecular imaging of heart disease
Cormode, DP; Skajaa, T; Lobatto, ME; Briley-Saebo, KC; Barazza, A; Gordon, R; Fisher, EA; Fayad, ZA; Mulder, WJM
2008 AUG 17 ;236(2):94-94, Abstracts of papers (American Chemical Society)
— id: 106239, year: 2008, vol: 236, page: 94, stat: Journal Article,

Nanocrystal Core High-Density Lipoproteins: A Multimodality Contrast Agent Platform
Cormode, DP; Skajaa, T; van Schooneveld, MM; Koole, R; Jarzyna, P; Lobatto, ME; Calcagno, C; Barazza, A; Gordon, RE; Zanzonico, P; Fisher, EA; Fayad, ZA; Mulder, WJM
2008 NOV ;8(11):3715-3723, Nano letters
High density lipoprotein (HDL) is an important natural nanoparticle that may be modified for biomedical imaging purposes. Here we developed a novel technique to create unique multimodality HDL mimicking nanoparticles by incorporation of gold, iron oxide, or quantum dot nanocrystals for computed tomography, magnetic resonance, and fluorescence imaging, respectively. By including additional labels in the corona of the particles, they were made multifunctional. The characteristics of these nanoparticles, as well as their in vitro and in vivo behavior, revealed that they closely mimic native HDL
— id: 90943, year: 2008, vol: 8, page: 3715, stat: Journal Article,

An ApoA-I mimetic peptide high-density-lipoprotein-based MRI contrast agent for atherosclerotic plaque composition detection
Cormode, DR; Briley-Saebo, KC; Mulder, WJM; Aguinaldo, JGS; Barazza, A; Ma, YQ; Fisher, EA; Fayad, ZA
2008 SEP ;4(9):1437-1444, Small (Weinheim an der Bergstrasse, Germany)
Cardiovascular disease is one of the prime causes of mortality throughout the world and there is a need for targeted and effective contrast agents to allow noninvasive imaging of the cholesterol-rich atherosclerotic plaques in arteries. A new, fully synthetic, high-density lipoprotein (HDL)-mimicking MRI contrast agent is developed, which enhances macrophage-rich areas of plaque in a mouse model of atherosclerosis by 94%. Confirmation of the targeting of this nanoparticulate agent is achieved using confocal microscopy by tracking a fluorescent lipid incorporated into the nanoparticle
— id: 89375, year: 2008, vol: 4, page: 1437, stat: Journal Article,

Atherosclerosis regression promoted by an LXR agonist is dependent on the chemokine receptor CCR7 and requires both LXR alpha and LXR beta
Feig, JE; Bradley, MN; Pineda-Torra, I; Randolph, GJ; Garabedian, MJ; Tontonoz, P; Fisher, EA
2008 JUN ;28(6):E43-E43, Arteriosclerosis, thrombosis, & vascular biology
— id: 86977, year: 2008, vol: 28, page: E43, stat: Journal Article,

Atherosclerosis regression promoted by an LXR agonist is dependent on the chemokine receptor CCR7 and requires both LXR and LXR
Feig, JE; Pineda-Torra, I; Garabedian, MJ; Fisher, EA
2008 MAR 11 ;51(10):A374-A375, Journal of the American College of Cardiology
— id: 78390, year: 2008, vol: 51, page: A374, stat: Journal Article,

Atheroprotective effects of HDL: beyond reverse cholesterol transport
Feig, Jonathan E; Shamir, Raanan; Fisher, Edward A
2008 Mar;9(3):196-203, Current drug targets
The risk of atherosclerosis is inversely related to circulating levels of high density lipoprotein (HDL) cholesterol. Notably, in large-scale epidemiologic studies, this association is independent of plasma levels of low density lipoprotein cholesterol levels. Pharmacologic agents, such as fibrates and niacin that increase HDL cholesterol levels have been associated with decreased cardiovascular events and beneficial effects on the coronary and carotid arteries. Furthermore, there is evidence that the risk of restenosis following vascular interventions is inversely related to HDL levels. This review considers the available data from mainly murine models on potential mechanisms by which HDL may exert these anti-atherogenic effects, namely through its role in reverse cholesterol transport, its effects on endothelial cells, and its anti-inflammatory/anti-oxidant activities. In addition to discussing a role for HDL in retarding atherosclerosis progression, we will also review how HDL may play a role in promoting regression of atherosclerotic lesions
— id: 78363, year: 2008, vol: 9, page: 196, stat: Journal Article,

Autophagy of an oxidized, aggregated protein beyond the ER: a pathway for remarkably late-stage quality control
Fisher, Edward A; Williams, Kevin Jon
2008 Jul 1;4(5):721-723, Autophagy
The authors recently reported a novel role for autophagy in late-stage quality control of a secreted protein, apolipoprotein-B(100) (apoB). Hepatocytes assemble this protein with triglycerides, cholesterol and other lipids into macromolecular complexes called lipoproteins. In what appears to be a normal response to diets rich in polyunsaturated fatty acids, which are readily peroxidized, apoB comes into contact with lipid peroxides in or after the Golgi apparatus. The protein becomes oxidatively damaged, aggregates, and is diverted out of the secretory pathway by autophagosomes, which deliver it to lysosomes for destruction. ApoB secretory control via autophagosomes is likely a key component of normal and pathological regulation of plasma lipoprotein levels, as well as a means for remarkably late-stage quality control of a secreted protein
— id: 81063, year: 2008, vol: 4, page: 721, stat: Journal Article,

Short-term pacing in the mouse alters cardiac expression of connexin43
Kontogeorgis, Andrianos; Kaba, Riyaz A; Kang, Eunice; Feig, Jonathan E; Gupta, Pritha P; Ponzio, Marc; Liu, Fangyu; Rindler, Michael J; Wit, Andrew L; Fisher, Edward A; Peters, Nicholas S; Gutstein, David E
2008 ;8:8-8, BMC Physiology
BACKGROUND: Cardiac insults such as ischemia, infarction, hypertrophy and dilatation are often accompanied by altered abundance and/or localization of the connexin43 gap junction protein, which may predispose towards arrhythmic complications. Models of chronic dyssynchronous cardiac activation have also been shown to result in redistribution of connexin43 in cardiomyocytes. We hypothesized that alterations in connexin43 expression and localization in the mouse heart might be induced by ventricular pacing over a short period of time. RESULTS: The subdiaphragmatic approach was used to pace a series of wild type mice for six hours before the hearts were removed for analysis. Mice were paced at 10-15% above their average anesthetized sinus rate and monitored to ensure 1:1 capture. Short-term pacing resulted in a significant reduction in connexin43 mRNA abundance, a partial redistribution of connexin43 from the sarcolemma to a non-sarcolemmal fraction, and accumulation of ubiquitinated connexin43 without a significant change in overall connexin43 protein levels. These early pacing-induced changes in connexin43 expression were not accompanied by decreased cardiac function, prolonged refractoriness or increased inducibility into sustained arrhythmias. CONCLUSION: Our data suggest that short-term pacing is associated with incipient changes in the expression of the connexin43 gap junction, possibly including decreased production and a slowed rate of degradation. This murine model may facilitate the study of early molecular changes induced by pacing and may ultimately assist in the development of strategies to prevent gap junction remodeling and the associated arrhythmic complications of cardiac disease
— id: 79562, year: 2008, vol: 8, page: 8, stat: Journal Article,

Decreased connexin43 expression in the mouse heart potentiates pacing-induced remodeling of repolarizing currents
Kontogeorgis, Andrianos; Li, Xiaodong; Kang, Eunice Y; Feig, Jonathan E; Ponzio, Marc; Kang, Guoxin; Kaba, Riyaz A; Wit, Andrew L; Fisher, Edward A; Morley, Gregory E; Peters, Nicholas S; Coetzee, William A; Gutstein, David E
2008 Nov;295(5):H1905-H1916, American journal of physiology. Heart & circulatory physiology
Gap junction redistribution and reduced expression, a phenomenon termed gap junction remodeling (GJR), is often seen in diseased hearts and may predispose towards arrhythmias. We have recently shown that short-term pacing in the mouse is associated with changes in connexin43 (Cx43) expression and localization, but not with increased inducibility into sustained arrhythmias. We hypothesized that short-term pacing, if imposed on murine hearts with decreased Cx43 abundance, could serve as a model for evaluating the electrophysiologic effects of GJR. We paced wildtype (normal Cx43 abundance) and heterozygous Cx43 knockout mice (Cx43(+/-), 66% mean reduction in Cx43) for six hours at 10-15% above their average sinus rate. We investigated the electrophysiologic effects of pacing on the whole animal using programmed electrical stimulation, and in isolated ventricular myocytes with patch clamp studies. Cx43(+/-) myocytes had significantly shorter action potential durations (APD) and increased steady state and inward rectifier potassium currents (Iss and IK1, respectively) compared to wildtype littermate cells. In Cx43(+/-) hearts, pacing resulted in significant prolongation of ventricular effective refractory period and action potential duration, and significant diminution of Iss compared to unpaced Cx43(+/-) hearts. However, these changes were not seen in paced wildtype mice. These data suggest that Cx43 abundance plays a critical role in regulating currents involved in myocardial repolarization and their response to pacing. Our study may aid in understanding how dyssynchronous activation of diseased, Cx43-deficient myocardial tissue can lead to electrophysiologic changes which may contribute to the worsened prognosis often associated with pacing in the failing heart. Key words: Connexin43, ventricular myocytes, mouse, gap junction
— id: 116200, year: 2008, vol: 295, page: H1905, stat: Journal Article,

Connexin40 imparts conduction heterogeneity to atrial tissue
Leaf, David E; Feig, Jonathan E; Vasquez, Carolina; Riva, Pamela L; Yu, Cindy; Lader, Joshua M; Kontogeorgis, Andrianos; Baron, Elvera L; Peters, Nicholas S; Fisher, Edward A; Gutstein, David E; Morley, Gregory E
2008 Oct 24;103(9):1001-1008, Circulation research
Impulse propagation in cardiac tissue is a complex process in which intercellular coupling through gap junction channels is a critical component. Connexin40 (Cx40) is an abundant gap junction protein that is expressed in atrial myocytes. Alterations in the expression of Cx40 have been implicated in atrial arrhythmogenesis. The purpose of the current study was to assess the role of Cx40 in atrial impulse propagation. High-resolution optical mapping was used to study conduction in the right and left atrial appendages of isolated Langendorff-perfused murine hearts. Wild-type (Cx40(+/+)), heterozygous (Cx40(+/-)), and knockout (Cx40(-/-)) mice, both adult and embryonic, were studied to assess the effects of reduced Cx40 expression on sinus node function and conduction velocity at different pacing cycle lengths (100 and 60 ms). In both adult and late-stage embryonic Cx40(+/+) mice, heterogeneity in CV was found between the right and left atrial appendages. Either partial (Cx40(+/-)) or complete (Cx40(-/-)) deletion of Cx40 was associated with the loss of conduction heterogeneity in both adult and embryonic mice. Additionally, sinus node impulse initiation was found to be ectopic in Cx40(-/-) mice at 15.5 days postcoitus, whereas Cx40(+/+) mice showed normal activation occurring near the crista terminalis. Our findings suggest that Cx40 plays an essential role in establishing interatrial conduction velocity heterogeneity in the murine model. Additionally, we describe for the first time a developmental requirement for Cx40 in normal sinus node impulse initiation at 15.5 days postcoitus
— id: 93330, year: 2008, vol: 103, page: 1001, stat: Journal Article,

Plasma carboxyl ester lipase activity modulates apolipoprotein B-containing lipoprotein metabolism in a transgenic mouse model
Li, L; Weng, W; Harrison, EH; Fisher, EA
2008 OCT ;57(10):1361-1368, Metabolism clinical & experimental
Pancreatic carboxyl ester lipase (CEL) is in the plasma of many mammals, including humans and rats, but not mice. In vitro, CEL hydrolyzes cholesterol esters of apolipoprotein B-containing lipoproteins (apo B-Lp). To study the effect of CEL on metabolism of apo B-Lp and atherosclerosis in vivo, apo E-knockout (EKO) mice, which have high plasma levels of apo B-Lp and are prone to atherosclerosis, were made to secrete CEL into plasma by introducing a transgene containing a liver-specific promoter and rat CEL complementary DNA. Plasma CEL activity in EKO-CEL mice was comparable with that found in rats. Evidence of modification of apo B-Lp by plasma CEL in vivo was an increase in the free cholesterol to cholesterol ester ratio of apo B-Lp from mice on chow or a Western-type diet. In addition, plasma total cholesterol levels were elevated in EKO-CEL mice, with the elevation found exclusively in the apo B-Lp fraction. Associated with the increase in steady-state apo B-Lp levels was an increase in the plasma half-life of very low-density lipoproteins (VLDL) in EKO-CEL mice, measured by the clearance rate of injected VLDL. Interestingly, despite the increase of apo B-Lp, the atherosclerotic lesion did not differ between EKO and EKO-CEL mice on a Western-type diet. In summary, our results demonstrate that plasma CEL modulates apo B-Lp metabolism in vivo. resulting in reduced VLDL clearance and elevated plasma cholesterol levels. (C) 2008 Elsevier Inc. All rights reserved.Pancreatic carboxyl ester lipase (CEL) is in the plasma of many mammals, including humans and rats, but not mice. In vitro, CEL hydrolyzes cholesterol esters of apolipoprotein B-containing lipoproteins (apo B-Lp). To study the effect of CEL on metabolism of apo B-Lp and atherosclerosis in vivo, apo E-knockout (EKO) mice, which have high plasma levels of apo B-Lp and are prone to atherosclerosis, were made to secrete CEL into plasma by introducing a transgene containing a liver-specific promoter and rat CEL complementary DNA. Plasma CEL activity in EKO-CEL mice was comparable with that found in rats. Evidence of modification of apo B-Lp by plasma CEL in vivo was an increase in the free cholesterol to cholesterol ester ratio of apo B-Lp from mice on chow or a Western-type diet. In addition, plasma total cholesterol levels were elevated in EKO-CEL mice, with the elevation found exclusively in the apo B-Lp fraction. Associated with the increase in steady-state apo B-Lp levels was an increase in the plasma half-life of very low-density lipoproteins (VLDL) in EKO-CEL mice, measured by the clearance rate of injected VLDL. Interestingly, despite the increase of apo B-Lp, the atherosclerotic lesion did not differ between EKO and EKO-CEL mice on a Western-type diet. In summary, our results demonstrate that plasma CEL modulates apo B-Lp metabolism in vivo. resulting in reduced VLDL clearance and elevated plasma cholesterol levels. (C) 2008 Elsevier Inc. All rights reserved
— id: 98122, year: 2008, vol: 57, page: 1361, stat: Journal Article,

Docosahexaenoic acid induces hepatic apolipoprotein B degradation by superoxide-mediated increase in lipid peroxidation and oxidative modification and aggregation of apolipoprotein B
Maitin, V; Willner, J; Fisher, EA
2008 JUN ;28(6):E95-E95, Arteriosclerosis, thrombosis, & vascular biology
— id: 86980, year: 2008, vol: 28, page: E95, stat: Journal Article,

Presecretory oxidation, aggregation, and autophagic destruction of apoprotein-B: a pathway for late-stage quality control
Pan, Meihui; Maitin, Vatsala; Parathath, Sajesh; Andreo, Ursula; Lin, Sharron X; St Germain, Carly; Yao, Zemin; Maxfield, Frederick R; Williams, Kevin Jon; Fisher, Edward A
2008 Apr 15;105(15):5862-5867, Proceedings of the National Academy of Sciences of the United States of America
Hepatic secretion of apolipoprotein-B (apoB), the major protein of atherogenic lipoproteins, is regulated through posttranslational degradation. We reported a degradation pathway, post-ER pre secretory proteolysis (PERPP), that is increased by reactive oxygen species (ROS) generated within hepatocytes from dietary polyunsaturated fatty acids (PUFA). We now report the molecular processes by which PUFA-derived ROS regulate PERPP of apoB. ApoB exits the ER; undergoes limited oxidant-dependent aggregation; and then, upon exit from the Golgi, becomes extensively oxidized and converted into large aggregates. The aggregates slowly degrade by an autophagic process. None of the oxidized, aggregated material leaves cells, thereby preventing export of apoB-lipoproteins containing potentially toxic lipid peroxides. In summary, apoB secretory control via PERPP/autophagosomes is likely a key component of normal and pathologic regulation of plasma apoB levels, as well as a means for remarkably late-stage quality control of a secreted protein
— id: 79301, year: 2008, vol: 105, page: 5862, stat: Journal Article,

ES-4 is a neutral cholesteryl ester hydrolase in hepatic cells
Parathath, S; Dogan, S; Joaquin, VA; Grauer, L; Harrison, EH; Fisher, EA
2008 JUN ;28(6):E63-E63, Arteriosclerosis, thrombosis, & vascular biology
— id: 86978, year: 2008, vol: 28, page: E63, stat: Journal Article,

Hyperglycemia impairs the beneficial remodeling of mouse atherosclerotic plaques
Parathath, S; Grauer, L; Joaquin, VA; Fisher, EA
2008 JUN ;28(6):E84-E84, Arteriosclerosis, thrombosis, & vascular biology
— id: 86979, year: 2008, vol: 28, page: E84, stat: Journal Article,

Fibrate therapy: an update
Remick, Joshua; Weintraub, Howard; Setton, Robert; Offenbacher, Joseph; Fisher, Edward; Schwartzbard, Arthur
2008 May-Jun;16(3):129-141, Cardiology in review
Fibrates are a class of lipid-lowering medication primarily used as second-line agents behind statins. Acting via the peroxisome proliferators-activated receptor-alpha, their main lipoprotein effects are to lower serum triglyceride levels and to raise high-density lipoprotein-cholesterol, with modest effects on low-density lipoprotein-cholesterol. However, many clinical trials indicate that fibrates may have benefits beyond simply altering one's lipid profile. Several angiographic studies show retardation in the progression of atherosclerotic lesions in coronary vessels. Although clinical trials have failed to show a reduction in mortality with fibrates, several post hoc analyses indicate that there may be a mortality benefit in patients with features of the metabolic syndrome. Given that fibrates are often used as second-line agents, it is essential they are safe to be given in combination with other agents, particularly statins and ezetimibe. Although the side-effect profile of fibrates includes gastrointestinal symptoms, increased liver function tests, a reversible rise in creatinine and myositis, in general, fibrates seem to be safe to use in combination with other lipid lowering medications. Thus far, fibrates have not shown a mortality benefit in randomized clinical trials; as a result, they cannot be considered first-line medication for the primary or secondary prevention of coronary artery disease
— id: 79383, year: 2008, vol: 16, page: 129, stat: Journal Article,

Phosphorylation of liver X receptor alpha selectively regulates target gene expression in macrophages
Torra, Ines Pineda; Ismaili, Naima; Feig, Jonathan E; Xu, Chong-Feng; Cavasotto, Claudio; Pancratov, Raluca; Rogatsky, Inez; Neubert, Thomas A; Fisher, Edward A; Garabedian, Michael J
2008 Apr;28(8):2626-2636, Molecular & cellular biology
Dysregulation of liver X receptor alpha (LXRalpha) activity has been linked to cardiovascular and metabolic diseases. Here, we show that LXRalpha target gene selectivity is achieved by modulation of LXRalpha phosphorylation. Under basal conditions, LXRalpha is phosphorylated at S198; phosphorylation is enhanced by LXR ligands and reduced both by casein kinase 2 (CK2) inhibitors and by activation of its heterodimeric partner RXR with 9-cis-retinoic acid (9cRA). Expression of some (AIM and LPL), but not other (ABCA1 or SREBPc1) established LXR target genes is increased in RAW 264.7 cells expressing the LXRalpha S198A phosphorylation-deficient mutant compared to those with WT receptors. Surprisingly, a gene normally not expressed in macrophages, the chemokine CCL24, is activated specifically in cells expressing LXRalpha S198A. Furthermore, inhibition of S198 phosphorylation by 9cRA or by a CK2 inhibitor similarly promotes CCL24 expression, thereby phenocopying the S198A mutation. Thus, our findings reveal a previously unrecognized role for phosphorylation in restricting the repertoire of LXRalpha-responsive genes
— id: 76646, year: 2008, vol: 28, page: 2626, stat: Journal Article,

Rapid regression of atherosclerosis: insights from the clinical and experimental literature
Williams, Kevin Jon; Feig, Jonathan E; Fisher, Edward A
2008 Feb;5(2):91-102, Nature clinical practice. Cardiovascular medicine
Looking back at animal and clinical studies published since the 1920s, the notion of rapid regression and stabilization of atherosclerosis in humans has evolved from a fanciful goal to one that might be achievable pharmacologically, even for advanced plaques. Our review of this literature indicates that successful regression of atherosclerosis generally requires robust measures to improve plasma lipoprotein profiles. Examples of such measures include extensive lowering of plasma concentrations of atherogenic apolipoprotein B (apoB)-lipoproteins and enhancement of 'reverse' lipid transport from atheromata into the liver, either alone or in combination. Possible mechanisms responsible for lesion shrinkage include decreased retention of apoB-lipoproteins within the arterial wall, efflux of cholesterol and other toxic lipids from plaques, emigration of foam cells out of the arterial wall, and influx of healthy phagocytes that remove necrotic debris and other components of the plaque. Unfortunately, the clinical agents currently available cause less dramatic changes in plasma lipoprotein levels, and, thereby, fail to stop most cardiovascular events. Hence, there is a clear need for testing of new agents expected to facilitate atherosclerosis regression. Additional mechanistic insights will allow further progress
— id: 135316, year: 2008, vol: 5, page: 91, stat: Journal Article,

Long-term outcomes in non-diabetic patients with metabolic syndrome undergoing revascularization for multi-vessel coronary artery disease
Yatskar, Leonid; Holper, Elizabeth; Bansilal, Sameer; Schwartzbard, Arthur; Lombardero, Manuel; Ramanathan, Krishnan; Feit, Frederick; Fisher, Edward; Faxon, David; Hochman, Judith S; Farkouh, Michael E
2008 Jun;198(2):389-395, Atherosclerosis
AIM: The influence of metabolic syndrome (MS) on long-term mortality and morbidity in multi-vessel coronary artery disease (MV-CAD) is unclear. We studied the impact of MS on long-term outcomes in non-diabetic patients (NDM) with MV-CAD undergoing coronary revascularization in the Bypass Angioplasty Revascularization Investigation (BARI) trial and registry. METHODS: BARI trial and registry patients were separated into those with diabetes (DM) and those without. NDM fulfilling the NCEP definition of MS were identified. Ten year follow-up data were obtained on mortality, MI and development of diabetes. The data were analyzed using Cox proportional hazard modeling. RESULTS: In the BARI trial and registry 2962 NDM were identified. Of those, 510 patients had 3 or more components of the BARI-modified NCEP definition for MS, while 445 patients had 2 components of the definition and were classified as the 'mixed group'. Compared to patients without MS, both MS group (RR=3.2, p<0.0001) and the mixed group (RR=1.9, p=0.02) had a higher incidence of DM over the 10-year follow-up. Type 2 DM was found to be highly associated with 10-year mortality (RR=1.65, p<0.0001). However, there was no statistically significant difference in the rate of death or MI at 5 and 10 years between NDM with or without MS. In multivariate analysis, the presence of MS was not associated with 10-year mortality in the BARI population (RR=0.93, p=0.62). CONCLUSION: In this BARI follow-up study, we have affirmed the role of MS in predicting the development of diabetes in NDM at baseline. The 10-year risk of mortality and MI was not greater in NDM with MS who had MV-CAD and underwent revascularization, compared to patients without MS. Further studies to evaluate MS patients with MV-CAD undergoing coronary revascularization are warranted
— id: 79378, year: 2008, vol: 198, page: 389, stat: Journal Article,

Reassessing the cardiovascular risks and benefits of thiazolidinediones
Zinn, Andrew; Felson, Sabrina; Fisher, Edward; Schwartzbard, Arthur
2008 Sep;31(9):397-403, Clinical cardiology
This article is designed for the general cardiologist, endocrinologist, and internist caring for patients with diabetes and coronary artery disease. Despite the burden of coronary disease in diabetics, little is known about the impact of commonly used oral hypoglycemic agents on cardiovascular outcomes. As the untoward effects of insulin resistance (IR) are increasingly recognized, there is interest in targeting this defect. Insulin resistance contributes to dyslipidemia, hypertension, inflammation, hypercoagulability, and endothelial dysfunction. The aggregate impact of this process is progression of systemic atherosclerosis and an increased risk of adverse cardiovascular outcomes. As such, much attention has been paid to the peroxisome-proliferator-activated receptor gamma (PPARg) agonists rosiglitazone and pioglitazone (thiazolidinediones [TZDs]). Many studies have demonstrated a beneficial effect on the atherosclerotic process; specifically, these agents have been shown to reduce markers of inflammation, retard progression of carotid intimal thickness, prevent restenosis after coronary stenting, and prevent cardiovascular death and myocardial infarction in 1 large trial. Such benefits come at the risk of fluid retention and heart failure (HF) exacerbation, and the net effect on plasma lipids is still poorly understood. Thus, the aggregate risk-benefit ratio is poorly defined. A recent meta-analysis has raised significant concerns regarding the overall cardiovascular safety of 1 particular PPARg agonist (rosiglitazone), prompting international debate and regulatory changes. This review scrutinizes the clinical evidence regarding the cardiovascular risks and benefits of PPARg agonists. Future studies of PPARg agonists, and other emerging drugs that treat IR and diabetes, must be designed to look at cardiovascular outcomes
— id: 105305, year: 2008, vol: 31, page: 397, stat: Journal Article,

Detecting and assessing macrophages in vivo to evaluate atherosclerosis noninvasively using molecular MRI
Amirbekian, V; Lipinski, MJ; Briley-Saebo, KC; Amirbekian, S; Aguinaldo, JGS; Weinreb, DB; Vucic, E; Frias, JC; Hyafil, F; Mani, V; Fisher, EA; Fayad, ZA
2007 JAN 16 ;104(3):961-966, Proceedings of the National Academy of Sciences of the United States of America
We investigated the ability of targeted immunomicelles to detect and assess macrophages in atherosclerotic plaque using MRI in vivo. There is a large clinical need for a noninvasive tool to assess atherosclerosis from a molecular and cellular standpoint. Macrophages play a central role in atherosclerosis and are associated with plaques vulnerable to rupture. Therefore, macrophage scavenger receptor (MSR) was chosen as a target for molecular MRI. MSR-targeted immunomicelles, micelles, and gadolinium-diethyltriaminepentaacetic acid (DTPA) were tested in ApoE-/- and WT mice by using in vivo MRI. Confocal laser-scanning microscopy colocalization, macrophage immunostaining and MRI correlation, competitive inhibition, and various other analyses were performed. In vivo MRI revealed that at 24 h postinjection, immunomicelles provided a 79% increase in signal intensity of atherosclerotic aortas in ApoE-/- mice compared with only 34% using untargeted micelles and no enhancement using gadolinium-DTPA. Confocal laser-scanning microscopy revealed colocalization between fluorescent immunomicelles and macrophages in plaques. There was a strong correlation between macrophage content in atherosclerotic plaques and the matched in vivo MRI results as measured by the percent normalized enhancement ratio. Monoclonal antibodies to MSR were able to significantly hinder immunomicelles from providing contrast enhancement of atherosclerotic vessels in vivo. Immunomicelles provided excellent validated in vivo enhancement of atherosclerotic plaques. The enhancement seen is related to the macrophage content of the atherosclerotic vessel areas imaged. Immunomicelles may aid in the detection of high macrophage content associated with plaques vulnerable to rupture
— id: 70615, year: 2007, vol: 104, page: 961, stat: Journal Article,

Magnetic resonance imaging of vulnerable atherosclerotic plaques: Current imaging strategies and molecular imaging probes
Briley-Saebo, KC; Mulder, WJM; Mani, V; Hyafil, F; Amirbekian, V; Aguinaldo, JGS; Fisher, EA; Fayad, ZA
2007 SEP ;26(3):460-479, Journal of magnetic resonance imaging
The vulnerability or destabilization of atherosclerotic plaques has been directly linked to plaque composition. Imaging modalities, such as magnetic resonance (MR) imaging, that allow for evaluation of plaque composition at a cellular and molecular level, could further improve the detection of vulnerable plaque and may allow for monitoring the efficacy of antiatherosclerotic therapies. In this review we focus on MR imaging strategies for the detection and evaluation of atherosclerotic plaques and their composition. We highlight recent advancements in the development of MR pulse sequences, computer image analysis, and the use of commercially available MR contrast agents, such as gadopentic acid (Gd-DTPA), for plaque characterization. We also discuss molecular imaging strategies that are currently being used to design specific imaging probes targeted to biochemical and cellular markers of atherosclerotic plaque vulnerability
— id: 74148, year: 2007, vol: 26, page: 460, stat: Journal Article,

Hyperlipidemia causes pancreatic inflammation and ductal proliferation in Apolipoprotein E deficient mice
Clair, JMS; Joaquin, VA; Fisher, EA; Bar-Sagi, D
2007 NOV ;35(4):414-415, Pancreas
— id: 75691, year: 2007, vol: 35, page: 414, stat: Journal Article,

Modified lipoproteins as contrast agents for molecular imaging
Cormode, DP; Mulder, WJM; Fisher, EA; Fayad, ZA
2007 DEC ;2(6):587-590, Future lipidology
— id: 75421, year: 2007, vol: 2, page: 587, stat: Journal Article,

Elevated plasma cholesterol does not affect brain Abeta in mice lacking the low-density lipoprotein receptor
Elder, Gregory A; Cho, Julie Y; English, Daniel F; Franciosi, Sonia; Schmeidler, James; Sosa, Miguel A Gama; Gasperi, Rita De; Fisher, Edward A; Mathews, Paul M; Haroutunian, Vahram; Buxbaum, Joseph D
2007 Aug;102(4):1220-1231, Journal of neurochemistry
Epidemiological studies support an association between vascular risk factors, including hypercholesterolemia, and Alzheimer's disease (AD). Recently, there has been much interest in the possibility that hypercholesterolemia might directly promote beta-amyloid (Abeta) production. Indeed, in vitro studies have shown that increasing cellular cholesterol levels enhances Abeta production. However, studies in AD transgenic mouse models have not consistently found that elevated plasma cholesterol leads to increased Abeta production or deposition in vivo. In this study, we determined whether elevated peripheral cholesterol influences Abeta production in mice with a null mutation of the low-density lipoprotein receptor (LDLR). We show that dramatically elevated plasma cholesterol levels, whether induced by high cholesterol, high fat, or high fat/high cholesterol diets, did not affect either levels of brain Abeta40, Abeta42, or APP, or the Abeta42/40 or APP-CTF/APP ratios, nor substantially alter brain cholesterol levels. ApoE protein levels in brain were, however, elevated, in LDLR-/- mice by post-transcriptional mechanisms. Collectively, these studies argue that plasma cholesterol levels do not normally regulate production of brain Abeta
— id: 73883, year: 2007, vol: 102, page: 1220, stat: Journal Article,

CCR7 is functionally required for atherosclerosis regression and is activated in vivo by LXR
Feig, JE; Hoffman, JR; Torra, IP; Garabedian, MJ; Fisher, EA
2007 ;27(6):E95-E95, Arteriosclerosis, thrombosis, & vascular biology
— id: 104580, year: 2007, vol: 27, page: E95, stat: Journal Article,

Lipid efflux factors are required for the regression of atherosclerosis independent of non-HDL cholesterol levels
Feig, JE; Mick, SL; Shamir, R; Parathath, S; Joaquin, VA; Thorngate, FE; Fisher, EA
2007 OCT 16 ;116(16):298-298, Circulation
— id: 75968, year: 2007, vol: 116, page: 298, stat: Journal Article,

Atherosclerosis regression promoted by an LXR agonist is dependent on the chemokine receptor CCR7
Feig, JE; Pmeda-Torra, I; Shamir, R; Joaquin, VA; Grauer, LS; Garabedian, MJ; Fisher, EA
2007 OCT 16 ;116(16):146-146, Circulation
— id: 75965, year: 2007, vol: 116, page: 146, stat: Journal Article,

CCR7 is functionally required for atherosclerosis regression and is activated by LXR
Feig, Jonathan E; Randolph, Gwendalyn J; Garabedian, Michael J; Fisher, Edward A
2007 ;1:30-30, Probe: the publication of research on biomedical endeavors
— id: 75322, year: 2007, vol: 1, page: 30, stat: Journal Article,

MD vs MD/PhD: my path and some words of advice
Fisher, Edward A
2007 ;1:11-12, Probe: the publication of research on biomedical endeavors
— id: 75313, year: 2007, vol: 1, page: 11, stat: Journal Article,

Golgi-associated maturation of very low density lipoproteins involves conformational changes in apolipoprotein B, but is not dependent on apolipoprotein E
Gusarova, V; Seo, J; Sullivan, ML; Watkins, SC; Brodsky, JL; Fisher, EA
2007 JUL 6 ;282(27):19453-19462, Journal of biological chemistry
The major protein component in secreted very low density lipoproteins (VLDL) is apoB, and it is established that these particles can reach sizes approaching 100 nm. We previously employed a cell-free system to investigate the nature of the vesicles in which this large cargo exits the endoplasmic reticulum (ER) (Gusarova, V., Brodsky, J. L., and Fisher, E. A. (2003) J. Biol. Chem. 278, 48051-48058). We found that apoB-containing lipoproteins exit the ER as dense lipid-protein complexes regardless of the final sizes of the particles and that further expansion occurs via post-ER lipidation. Here, we focused on maturation in the Golgi apparatus. In three separate approaches, we found that VLDL maturation (as assessed by changes in buoyant density) was associated with conformational changes in apoB. In addition, as the size of VLDL expanded, apoE concentrated in a subclass of Golgi microsomes or Golgi-derived vesicles that co-migrated with apoB-containing microsomes or vesicles, respectively. A relationship between apoB and apoE was further confirmed in co-localization studies by immunoelectron microscopy. These combined results are consistent with previous suggestions that apoE is required for VLDL maturation. To our surprise, however, we observed robust secretion of mature VLDL when apoE synthesis was inhibited in either rat hepatoma cells or apoE(-/-) mouse primary hepatocytes. We conclude that VLDL maturation in the Golgi involves apoB conformational changes and that the expansion of the lipoprotein does not require apoE; rather, the increase in VLDL surface area favors apoE binding
— id: 73390, year: 2007, vol: 282, page: 19453, stat: Journal Article,

The Hsp110 molecular chaperone stabilizes apolipoprotein B from endoplasmic reticulum-associated degradation (ERAD)
Hrizo, SL; Gusarova, V; Habiel, DM; Goeckeler, JL; Fisher, EA; Brodsky, JL
2007 NOV 9 ;282(45):32665-32675, Journal of biological chemistry
Apolipoprotein B ( apoB) is the most abundant protein in low density lipoproteins and plays key roles in cholesterol homeostasis. The co- translational degradation of apoB is controlled by fatty acid levels in the endoplasmic reticulum ( ER) and is mediated by the proteasome. To define the mechanism of apoB degradation, we employed a cell- free system in which proteasome-dependent degradation is recapitulated with yeast cytosol, and we developed an apoB yeast expression system. We discovered that a yeast Hsp110, Sse1p, associates with and stabilizes apoB, which contrasts with data indicating that select Hsp70s and Hsp90s facilitate apoB degradation. However, the Ssb Hsp70 chaperones have no effect on apoB turnover. To determine whether our results are relevant in mammalian cells, Hsp110 was overexpressed in hepatocytes, and enhanced apoB secretion was observed. This study indicates that chaperones within distinct complexes can play unique roles during ER- associated degradation ( ERAD), establishes a role for Sse1/ Hsp110 in ERAD, and identifies Hsp110 as a target to lower cholesterol
— id: 75125, year: 2007, vol: 282, page: 32665, stat: Journal Article,

Recipes for creating animal models of diabetic cardiovascular disease
Hsueh, W; Abel, ED; Breslow, JL; Maeda, N; Davis, RC; Fisher, EA; Dansky, H; McClain, DA; McIndoe, R; Wassef, MK; Rabadan-Diehl, C; Goldberg, IJ
2007 MAY 25 ;100(10):1415-1427, Circulation research
For more than 50 years, investigators have unsuccessfully tried to recreate in experimental animals the cardiovascular complications of diabetes seen in humans. In particular, accelerated atherosclerosis and dilated cardiomyopathy, the major causes of mortality in patients with diabetes, have been conspicuously absent in many mouse models of the disease. Under the auspices of the NIH, the Animal Models of Diabetic Complications Consortium has worked to address this issue. This effort has focused on the development of mouse models because of the high level of genomic information available and the many well-developed genetic manipulations that may be performed in mice. Importantly, the consortium has also worked to standardize many methods to assess metabolic and cardiovascular end points for measurement of the diabetic state and its macrovascular complications. Finally, for maximum benefits from these animal models in the study of atherosclerosis and of other diabetic complications, the consortium has created a system for sharing both the animal models and the accumulated phenotypic data with the greater scientific community
— id: 73050, year: 2007, vol: 100, page: 1415, stat: Journal Article,

Exercise-induced increases in oxidized low-density lipoprotein are associated with adverse outcomes in chronic heart failure
Jorde, UP; Colombo, PC; Ahuja, K; Hudaihed, A; Onat, D; Diaz, T; Hirsh, DS; Fisher, EA; Tseng, CH; Vittorio, TJ
2007 NOV ;13(9):759-764, Journal of cardiac failure
Background: Oxidative stress is an important pathophysiologic feature in chronic heart failure (CHF) and may in part result from the inability to counteract acute surges of circulating oxidant products. Oxidized low-density lipoprotein (oxLDL) is an emerging prognostic marker in CHF. Accordingly, we investigated the effect of exercise-induced oxidative stress on circulating levels of oxLDL and its association with clinical outcomes in CHF. Methods and Results: Plasma levels of oxLDL and low-density lipoprotein cholesterol (LDL-c) were measured at rest and after maximal exercise in 48 subjects with CHF and 12 healthy controls. Subjects with CHF had a higher baseline oxLDL (77.7 +/- 3.2 U/L vs 57.9 +/- 5.0 U/L, P = .01) and a higher baseline oxLDL/LDL-c ratio (0.87 +/- 0.04 vs 0.49 +/- 0.04, P <= .001). Exercise induced an increase in oxLDL in subjects with CHF (77.7 +/- 3.2 U/L to 85.3 +/- 3.0 U/L, P >= .001) but not in controls (57.9 +/- 5.0 to 61.4 +/- 5.5, P = .17). In 39 subjects for whom follow-up data were available, an increase in oxLDL of more than 11.0 U/L was associated with an increased risk to meet a combined end point of death and need for ventricular assist device or heart transplant during a 19-month follow-up period (hazard ratio 8.6; 95% confidence interval 1.0-73.8, P = .05); this remained significant when adjusted for peak oxygen consumption, left ventricular ejection fraction, New York Heart Association class, sex, and age (hazard ratio 46.6, 95% confidence interval 1.5-1438.1, P = .02). Conclusion: Plasma oxLDL and the oxLDL/LDL-c ratio are elevated in subjects with CHF. Whether assessment of oxLDL during maximal exercise allows early identification of subjects at highest risk for adverse outcomes should be systematically investigated
— id: 75464, year: 2007, vol: 13, page: 759, stat: Journal Article,

Impaired ABCA-1 mediated cholesterol efflux in hypoxic macrophages
Mick, SL; Parathath, S; Maitin, V; Feig, JE; Grauer, L; Joaquin, V; Habiel, D; Fisher, EA
2007 OCT 16 ;116(16):160-160, Circulation
— id: 75966, year: 2007, vol: 116, page: 160, stat: Journal Article,

Therapeutic approach to childhood hypercholesterolemia
Shamir, Raanan; Feig, Jonathan E; Fisher, Edward A
2007 Dec;5(2):649-655, Pediatric endocrinology reviews : PER
Hypercholesterolemia is associated with increased risk of premature cardiovascular disease in adults, while early atherosclerotic lesions (reversible fatty streaks and non reversible fibrous plaques) are also associated with cardiovascular risk factors including low density lipoprotein-cholesterol (LDL-C). Although LDL-C is a risk factor that should be addressed in high risk children such as those with familial hypercholesterolemia, it is unclear, at present, whether there is a certain plasma LDL-C level that would call for an intervention regardless of the etiology of elevated LDL-C. Therefore, at present, screening the entire population to identify subjects with hypercholesterolemia is not justified. The aims of this review are to familiarize the reader with inherited diseases that are associated with elevated LDL-C and discuss the management of children with elevated LDL-C
— id: 133523, year: 2007, vol: 5, page: 649, stat: Journal Article,

ApoE derived lipopeptide containing gadolinium mixed micelles for macrophage Imaging in ApoE ko mice
Vucic, E; Briley-Saboe, KC; Leupold, E; Aguinaldo, JG; Amirbekian, V; Fisher, EA; Dathe, M; Fayad, ZA
2007 OCT 16 ;116(16):412-412, Circulation
— id: 75970, year: 2007, vol: 116, page: 412, stat: Journal Article,

Cellular and molecular mechanisms for rapid regression of atherosclerosis: from bench top to potentially achievable clinical goal
Williams, Kevin Jon; Feig, Jonathan E; Fisher, Edward A
2007 Aug;18(4):443-450, Current opinion in lipidology
PURPOSE OF REVIEW: Decades of literature have unambiguously demonstrated regression and remodeling of atherosclerotic lesions, including advanced plaques. Recent insights into underlying mechanisms are reviewed. RECENT FINDINGS: Factors promoting regression include decreased apolipoprotein B-lipoprotein retention within the arterial wall, efflux of cholesterol and other harmful lipids from plaques, and emigration of lesional foam cells followed by entry of healthy phagocytes that remove necrotic debris and other plaque components. Cellular lipid efflux and foam cell emigration can occur surprisingly rapidly once the plaque milieu is improved. Lipid efflux and foam cell emigration each involve specific molecular mediators, many of which have been identified. Necrotic debris removal can be surprisingly comprehensive, with essentially full disappearance documented in animal models. SUMMARY: The essential prerequisite for regression is robust improvement in plaque milieu, meaning large plasma reductions in atherogenic apolipoprotein B-lipoproteins or brisk enhancements in 'reverse' lipid transport from plaque into liver. Importantly, the processes of regression are consistent with rapid correction of features characteristic of the rupture-prone, vulnerable plaques responsible for acute coronary syndromes. New interventions to lower apolipoprotein B-lipoprotein levels and enhance reverse lipid transport may allow regression to become a widespread clinical goal. Strategies based on recent mechanistic insights may facilitate further therapeutic progress
— id: 73868, year: 2007, vol: 18, page: 443, stat: Journal Article,

MSR-targeted immunomicelles-mediated MRI enhancement of atherosclerosis is associated with macrophage content of atherosclerotic plaques and inhibited by monoclonal antibodies to MSR
Amirbekian, S; Amirbekian, V; Lipinski, MJ; Briley-Saboe, K; Aguinaldo, JG; Hyafil, F; Weinreb, OB; Vucic, E; Frias, JC; Mani, V; Fisher, EA; Fayad, ZA
2006 OCT 31 ;114(18):338-338, Circulation
— id: 69551, year: 2006, vol: 114, page: 338, stat: Journal Article,

MRI efficacy of spherical and discoidal gadolinium-labeled ApoA-I/phospholipid nanoparticies in the vessel wall of ApoE-/- mice
Briley-Saebo, KC; Ma, YQ; Aquinaldo, JGS; Mani, V; Vucic, E; Frias, JC; Williams, KJ; Fisher, EA; Fayad, ZA
2006 OCT 31 ;114(18):323-323, Circulation
— id: 69550, year: 2006, vol: 114, page: 323, stat: Journal Article,

TLR signaling and trapped vascular dendritic cells in the development of atherosclerosis
Doherty, TM; Fisher, EA; Arditi, M
2006 MAY ;27(5):222-227, Trends in immunology
The Framingham Heart Study established a link between serum lipoproteins and atherosclerosis but a crucially important feature of the disease has been neglected: it is primarily an immunological disorder. Here, we reframe atherosclerosis in terms of recent progress in understanding the immunological mechanisms underlying the disorder, and advance a new conceptual model for the future. We place vascular dendritic cells squarely at the forefront, and propose that a sentinel network of vascular dendritic cells (DCs) sample and process exogenous and endogenous antigens that can trigger an inflammatory nidus within the arterial wall. Our model postulates that two components are essential to the development of atheromata: vascular DCs and intact myeloid differentiation (MyD)88-dependent signaling by Toll-like receptors
— id: 64484, year: 2006, vol: 27, page: 222, stat: Journal Article,

CCR7 is functionally required for atherosclerosis regression and is activated by LXR
Feig, JE; Ma, YQ; Randolph, GJ; Torra, IP; Garabedian, MJ; Fisher, EA
2006 MAY ;26(5):E50-E51, Arteriosclerosis, thrombosis, & vascular biology
— id: 63866, year: 2006, vol: 26, page: E50, stat: Journal Article,

Properties of a versatile nanoparticle platform contrast agent to image and characterize atherosclerotic plaques by magnetic resonance imaging
Frias, JC; Ma, YQ; Williams, KJ; Fayad, ZA; Fisher, EA
2006 OCT 11 ;6(10):2220-2224, Nano letters
The need for more specific and selective contrast agents for magnetic resonance imaging motivated us to prepare a new nanoparticle agent based on high-density lipoproteins (HDL). This second generation contrast agent can be prepared in three different ways. The HDL nanoparticles (rHDL) were fully characterized by FPLC and gel electrophoresis. The flexibility of the platform also allows us to incorporate optical probes into rHDL for localization ex vivo by confocal fluorescence microscopy. The contrast-agent-containing nanoparticles were injected into mice that develop atherosclerotic lesions. Magnetic resonance imaging of the animals showed clear enhancement of the atherosclerotic plaques
— id: 69000, year: 2006, vol: 6, page: 2220, stat: Journal Article,

MRI to detect atherosclerosis with gadolinium-containing immunomicelles targeting the macrophage scavenger receptor
Lipinski, MJ; Amirbekian, V; Frias, JC; Aguinaldo, JGS; Mani, V; Briley-Saebo, KC; Fuster, V; Fallon, JT; Fisher, EA; Fayad, ZA
2006 SEP ;56(3):601-610, Magnetic resonance in medicine
The ability to specifically image macrophages may enable improved detection and characterization of atherosclerosis. In this study we evaluated the in vitro uptake of gadolinium (Gd)-containing immunomicelles (micelles linked to macrophage-specific antibody), micelles, and standard contrast agents by murine macrophages, and sought to determine whether immunomicelles and micelles improve ex vivo imaging of apolipoprotein E knockout (ApoE KO) murine atherosclerosis. Murine RAW 264.7 macrophages were incubated with Gd-DTPA, micelles, and immunomicelles. Cell pellets were prepared and imaged using a 1.5 T MR system with an inversion recovery spin-echo sequence to determine the in vitro T-1 values. Ex vivo analysis of mouse aortas was performed using a 9.4T MR system with a high-spatial-resolution sequence (78 x 39 x 78 mu m(3)). The T-1 value was significantly decreased in cells treated with micelles compared to Gd-DTPA (P < 0.0001), and in cells incubated at VC with immunomicelles compared to micelles (P < 0.05). Ex vivo MRI signal intensity (SI) was significantly increased by 81% and 20% in aortas incubated with immunomicelles and micelles, respectively. Confocal microscopy demonstrated in vitro and ex vivo uptake of fluorescent immunomicelles by macrophages. Immunomicelles and micelles improve in vitro and ex vivo MR detection of macrophages, and may prove useful in the detection of macrophage-rich plaques
— id: 68634, year: 2006, vol: 56, page: 601, stat: Journal Article,

Transcriptional regulation of chemokine receptor CCR7 by Liver X Receptor
Ma, YQ; Feig, JE; Torra, IP; Garabedian, MJ; Fisher, EA
2006 MAY ;26(5):E99-E99, Arteriosclerosis, thrombosis, & vascular biology
— id: 63871, year: 2006, vol: 26, page: E99, stat: Journal Article,

Recombinant HDL-like nanoparticles are magnetic resonance imaging agents for evaluation of atherosclerotic plaques
Ma, YQ; Frias, JC; Saeboe, K; Fayad, ZA; Fisher, EA
2006 MAY ;26(5):E54-E54, Arteriosclerosis, thrombosis, & vascular biology
— id: 63867, year: 2006, vol: 26, page: E54, stat: Journal Article,

Severe macrophage hypoxia alters expression of genes of cholesterol metabolism and transport and converts them to a foam-cell like phenotype
Mick, SL; Feig, JE; Habiel, DM; Gardner, LB; Fisher, EA
2006 MAY ;26(5):E79-E79, Arteriosclerosis, thrombosis, & vascular biology
— id: 63869, year: 2006, vol: 26, page: E79, stat: Journal Article,

Cotranslocational degradation protects the stressed endoplasmic reticulum from protein overload
Oyadomari, Seiichi; Yun, Chi; Fisher, Edward A; Kreglinger, Nicola; Kreibich, Gert; Oyadomari, Miho; Harding, Heather P; Goodman, Alan G; Harant, Hanna; Garrison, Jennifer L; Taunton, Jack; Katze, Michael G; Ron, David
2006 Aug 25;126(4):727-739, Cell
The ER's capacity to process proteins is limited, and stress caused by accumulation of unfolded and misfolded proteins (ER stress) contributes to human disease. ER stress elicits the unfolded protein response (UPR), whose components attenuate protein synthesis, increase folding capacity, and enhance misfolded protein degradation. Here, we report that P58(IPK)/DNAJC3, a UPR-responsive gene previously implicated in translational control, encodes a cytosolic cochaperone that associates with the ER protein translocation channel Sec61. P58(IPK) recruits HSP70 chaperones to the cytosolic face of Sec61 and can be crosslinked to proteins entering the ER that are delayed at the translocon. Proteasome-mediated cytosolic degradation of translocating proteins delayed at Sec61 is cochaperone dependent. In P58(IPK-/-) mice, cells with a high secretory burden are markedly compromised in their ability to cope with ER stress. Thus, P58(IPK) is a key mediator of cotranslocational ER protein degradation, and this process likely contributes to ER homeostasis in stressed cells
— id: 69025, year: 2006, vol: 126, page: 727, stat: Journal Article,

Gene expression changes in foam cells and the role of chemokine receptor CCR7 during atherosclerosis regression in ApoE-deficient mice
Trogan, Eugene; Feig, Jonathan E; Dogan, Snjezana; Rothblat, George H; Angeli, Veronique; Tacke, Frank; Randolph, Gwendalyn J; Fisher, Edward A
2006 Mar 7;103(10):3781-3786, Proceedings of the National Academy of Sciences of the United States of America
Atherosclerosis regression is an important clinical goal. In previous studies of regression in mice, the rapid loss of plaque foam cells was explained by emigration to lymph nodes, a process reminiscent of dendritic cells. In the present study, plaque-containing arterial segments from apoE-/- mice were transplanted into WT recipient normolipidemic mice or apoE-/- mice. Three days after transplant, in the WT regression environment, plaque size decreased by approximately 40%, and foam cell content by approximately 75%. In contrast, both parameters increased in apoE-/- recipients. Foam cells were isolated by laser capture microdissection. In WT recipients, there were 3- to 6-fold increases in foam cells of mRNA for liver X receptor alpha and cholesterol efflux factors ABCA1 and SR-BI. Although liver X receptor alpha was induced, there was no detectable expression of its putative activator, peroxisome proliferator-activated receptor gamma. Expression levels of VCAM or MCP-1 were reduced to 25% of levels in pretransplant or apoE-/- recipient samples, but there was induction at the mRNA and protein levels of chemokine receptor CCR7, an essential factor for dendritic cell migration. Remarkably, when CCR7 function was abrogated in vivo by treatment of WT recipients with antibodies to CCR7 ligands CCL19 and CCL21, lesion size and foam cell content were substantially preserved. In summary, in foam cells during atherosclerosis regression, there is induction of CCR7 and a requirement for its function. Taken with the other gene expression data, these results in vivo point to complex relationships among the immune system, nuclear hormone receptors, and inflammation during regression
— id: 63807, year: 2006, vol: 103, page: 3781, stat: Journal Article,

Translocation efficiency of apolipoprotein B is determined by the presence of beta-sheet domains, not pause transfer sequences
Yamaguchi, J; Conlon, DM; Liang, JJ; Fisher, EA; Ginsberg, HN
2006 SEP 15 ;281(37):27063-27071, Journal of biological chemistry
Cotranslational translocation of apoB100 across the endoplasmic reticulum (ER) membrane is inefficient, resulting in exposure of nascent apoB on the cytosolic surface of the ER. This predisposes apoB100 to ubiquitinylation and targeting for proteasomal degradation. It has been suggested that pause transfer sequences (
— id: 68669, year: 2006, vol: 281, page: 27063, stat: Journal Article,

Ezetimibe: rationale and role in the management of hypercholesterolemia
Yatskar, Leonid; Fisher, Edward A; Schwartzbard, Arthur
2006 Feb;29(2):52-55, Clinical cardiology
Elevated low-density lipoprotein (LDL) cholesterol plays an important role in the development of atherosclerosis. In part, plasma LDL levels are dependent on cholesterol absorption in the intestine and the rate of intrinsic cholesterol synthesis. Therapy with 3-hydroxy-3-methylglutaryl coenzyme A-reductase inhibitors has often proven to be successful in reducing plasma LDL levels. However, a significant number of patients do not reach their target LDL levels despite statin therapy. As is reviewed, drugs that inhibit cholesterol absorption are a useful adjunct to lipid-lowering therapy by statins. This review discusses the mechanisms involved in intestinal absorption of cholesterol and its transport as potential targets of newer agents that affect cholesterol absorption. The use of bile acid sequestrants and esters of plant stanols, as well as other intestinally active agents for reducing plasma LDL levels, has been limited by side effects and difficulties in patient compliance. In contrast, the new selective cholesterol transporter inhibitor ezetimibe has been demonstrated to reduce plasma LDL alone or in combination with statins without significant adverse effects. In spite of the robust lipid-lowering data with ezetimibe, questions about clinical outcomes, safety, and efficacy in various combinations remain.
— id: 73009, year: 2006, vol: 29, page: 52, stat: Journal Article,

Recombinant HDL-like nanoparticles: a specific contrast agent for MRI of atherosclerotic plaques
Frias, Juan C; Williams, Kevin Jon; Fisher, Edward A; Fayad, Zahi A
2004 Dec 22;126(50):16316-16317, Journal of the American Chemical Society
A new contrast agent for MRI based on recombinant HDL-like nanoparticles has been prepared. It shows a great potential as a contrast agent for atherosclerotic plaques in a relative short time (24 h post-injection) as it is selective for the plaques and is an endogenous molecule. It also can distinguish between different types of plaques as the enhancement obtained is different, depending on plaque composition
— id: 133564, year: 2004, vol: 126, page: 16316, stat: Journal Article,

Mouse model of heterotopic aortic arch transplantation
Chereshnev, Igor; Trogan, Eugene; Omerhodzic, Sabina; Itskovich, Vitalii; Aguinaldo, Juan-Gilberto; Fayad, Zahi A; Fisher, Edward A; Reis, Ernane D
2003 May 15;111(2):171-176, Journal of surgical research
BACKGROUND: Syngeneic heterotopic transplantation of segments of descending thoracic aortas containing atherosclerotic lesions from hypercholesterolemic mice into normocholesterolemic recipients has been useful for studies on plaque regression and stabilization. Because lesion development is more rapid and exuberant in the aortic arch, a technique of transplantation of the mouse aortic arch was developed. MATERIALS AND METHODS: C57BL/6, apoE-deficient (apoE-/-) (hypercholesterolemic) mice were fed a Western diet for 22 weeks and used as donors of aortic-arch segments containing atherosclerotic lesions. Twenty syngeneic transplants were performed on age-matched wild-type (normocholesterolemic) mice. Aortic arches containing atherosclerotic lesions were implanted on the abdominal aorta of recipient mice by end-to-side microsurgical anastomosis. Two weeks after transplantation, grafts were noninvasively imaged in vivo by magnetic resonance (MR) microscopy. Grafts harvested four weeks after transplantation were submitted for histological examination. RESULTS: All recipients survived the entire follow-up period (1 month) without complications. Duration of recipient procedure ranged from 90 to 120 (mean, 105) min; aortic clamping time varied from 45 to 60 min. In vivo MR microscopy demonstrated patency of the grafts and wall thickening that corresponded to the preexisting atherosclerotic lesions. Histology confirmed patency and atherosclerotic thickening of the grafts, and showed no evidence of acute tissue damage. CONCLUSIONS: Syngeneic transplantation of the aortic arch in mice represents a useful alternative model for studies on morphology, imaging, and mechanisms of atherosclerosis. The curvature of the aortic arch is preserved after implantation onto the abdominal aorta, providing clear landmarks for noninvasive assessment using MR
— id: 37271, year: 2003, vol: 111, page: 171, stat: Journal Article,

Serial, noninvasive, in vivo magnetic resonance microscopy detects the development of atherosclerosis in apolipoprotein E-deficient mice and its progression by arterial wall remodeling
Choudhury, Robin P; Fayad, Zahi A; Aguinaldo, J Gilberto; Itskovich, Vitalii V; Rong, James X; Fallon, John T; Fisher, Edward A
2003 Feb;17(2):184-189, Journal of magnetic resonance imaging
PURPOSE: To test the ability of serial, in vivo magnetic resonance microscopy (MRM) to detect the development of atherosclerosis and quantify its progression in apolipoprotein E-deficient mice. MATERIALS AND METHODS: The abdominal aortae of six ApoE(-/-) and three wild-type (WT) control mice were imaged by MRM at 9.4T. Proton density weighted images were obtained (TR = 2000, TE = 9 msec) using four signal averages. The image resolution was 109 x 109 x 500 microm(3). The six ApoE(-/-) mice underwent serial MRM three to five times over a period < or = 44 weeks. Multiple, anatomically aligned MRM slices (N = 6-11 per time point, total 202) were compared serially in each animal. RESULTS: The abdominal aorta remained free of atherosclerosis until 20 weeks of age but thereafter, atherosclerosis was identified in all ApoE(-/-) mice (P < 0.05 to P < 0.001), but no WT controls. Lesion progression was accompanied by positive remodeling in which atherosclerosis within the aortic wall was accommodated by an increase in total cross sectional area (P < 0.01), while lumen area was unchanged. CONCLUSION: Serial MRM demonstrated the development and progression of atherosclerosis in mouse aorta. Importantly, progression of atherosclerosis could be identified within individual animals. By following the same aortic lesions over time, MRM demonstrated that progression of atherosclerosis in mice is associated with positive arterial remodeling
— id: 37276, year: 2003, vol: 17, page: 184, stat: Journal Article,

The endoplasmic reticulum is the site of cholesterol-induced cytotoxicity in macrophages
Feng, Bo; Yao, Pin Mei; Li, Yankun; Devlin, Cecilia M; Zhang, Dajun; Harding, Heather P; Sweeney, Michele; Rong, James X; Kuriakose, George; Fisher, Edward A; Marks, Andrew R; Ron, David; Tabas, Ira
2003 Sep;5(9):781-792, Nature cell biology
Excess cellular cholesterol induces apoptosis in macrophages, an event likely to promote progression of atherosclerosis. The cellular mechanism of cholesterol-induced apoptosis is unknown but had previously been thought to involve the plasma membrane. Here we report that the unfolded protein response (UPR) in the endoplasmic reticulum is activated in cholesterol-loaded macrophages, resulting in expression of the cell death effector CHOP. Cholesterol loading depletes endoplasmic reticulum calcium stores, an event known to induce the UPR. Furthermore, endoplasmic reticulum calcium depletion, the UPR, caspase-3 activation and apoptosis are markedly inhibited by selective inhibition of cholesterol trafficking to the endoplasmic reticulum, and Chop(-/-) macrophages are protected from cholesterol-induced apoptosis. We propose that cholesterol trafficking to endoplasmic reticulum membranes, resulting in activation of the CHOP arm of the UPR, is the key signalling step in cholesterol-induced apoptosis in macrophages
— id: 37270, year: 2003, vol: 5, page: 781, stat: Journal Article,

Characterization of aortic root atherosclerosis in ApoE knockout mice: high-resolution in vivo and ex vivo MRM with histological correlation
Itskovich, V V; Choudhury, R P; Aguinaldo, J G S; Fallon, J T; Omerhodzic, S; Fisher, E A; Fayad, Z A
2003 Feb;49(2):381-385, Magnetic resonance in medicine
In vivo, cardiac-gated, black-blood, and ex vivo magnetic resonance microscopy (MRM) images of the aortic root, and histopathology data were obtained from 12 transgenic and wild-type (WT) mice. MRM was performed using a black-blood imaging spin-echo sequence with upstream and downstream in-flow saturation pulses to obtain aortic root images in three contrast techniques: proton density-weighted (PDW), T(1)- (T(1)W), and T(2)-weighted (T(2)W). Aortic wall thickness and area were measured and correlated with histopathology data (R > 0.90). Ex vivo lesion components (lipid core, fibrous tissue, and cell tissue) were identified and characterized by differing image contrast in PDW, T(1)W, and T(2)W MRM, and by histopathology. The differences between WT and transgenic mice for maximal wall thickness and area were statistically significant (P < 0.05). This study demonstrates the feasibility of in vivo murine aortic root lesion assessment and ex vivo plaque characterization by MRM
— id: 37275, year: 2003, vol: 49, page: 381, stat: Journal Article,

Overexpression of the tumor autocrine motility factor receptor Gp78, a ubiquitin protein ligase, results in increased ubiquitinylation and decreased secretion of apolipoprotein B100 in HepG2 cells
Liang, Jun-Shan; Kim, Tonia; Fang, Shengyun; Yamaguchi, Junji; Weissman, Allan M; Fisher, Edward A; Ginsberg, Henry N
2003 Jun 27;278(26):23984-23988, Journal of biological chemistry
Apolipoprotein B100 (apoB) is a large (520-kDa) complex secretory protein; its secretion is regulated posttranscriptionally by several degradation pathways. The best described of these degradative processes is co-translational ubiquitinylation and proteasomal degradation of nascent apoB, involving the 70- and 90-kDa heat shock proteins and the multiple components of the proteasomal pathway. Ubiquitinylation involves several proteins, including ligases called E3s, that coordinate the covalent binding of ubiquitin to target proteins. The recent discovery that tumor autocrine motility factor receptor, also known as gp78, is an endoplasmic reticulum (ER)-associated E3, raised the possibility that this E3 might be involved in the ER-associated degradation of nascent apoB. In a series of experiments in HepG2 cells, we demonstrated that overexpression of gp78 was sufficient for increased ubiquitinylation and proteasomal degradation of apoB, with reduced secretion of apoB-lipoproteins. This action of gp78 was specific: overexpression of the protein did not affect secretion of either albumin or apolipoprotein AI. Furthermore, overexpression of a cytosolic E3, Itch, had no effect on apoB secretion. Finally, using an in vitro translation system, we demonstrated that gp78 led to increased ubiquitinylation and proteasomal degradation of apoB48. Together, these results indicate that an ER-associated protein, gp78, is a bona fide E3 ligase in the apoB ER-associated degradation pathway
— id: 37273, year: 2003, vol: 278, page: 23984, stat: Journal Article,

Eliminating atherogenesis in mice by switching off hepatic lipoprotein secretion
Lieu, Hsiao D; Withycombe, Shannon K; Walker, Quinn; Rong, James X; Walzem, Rosemary L; Wong, Jinny S; Hamilton, Robert L; Fisher, Edward A; Young, Stephen G
2003 Mar 11;107(9):1315-1321, Circulation
BACKGROUND: LDL receptor-deficient 'apolipoprotein (apo)-B100-only' mice (Ldlr-/-Apob100/100 have elevated LDL cholesterol levels on a chow diet and develop severe aortic atherosclerosis. We hypothesized that both the hypercholesterolemia and the susceptibility to atherosclerosis could be eliminated by switching off hepatic lipoprotein production. METHODS AND RESULTS: We bred Ldlr-/-Apob100/100 mice that were homozygous for a conditional allele for Mttp (the gene for microsomal triglyceride transfer protein) and the inducible Mx1-Cre transgene. In these animals, which we called 'Reversa mice,' the hypercholesterolemia could be reversed, without modifying the diet or initiating a hypolipidemic drug, by the transient induction of Cre expression in the liver. After Cre induction, hepatic Mttp expression was virtually eliminated (as judged by quantitative real-time PCR), hepatic lipoprotein secretion was abolished (as judged by electron microscopy), and LDLs were virtually eliminated from the plasma. Intestinal lipoprotein production was unaffected. In mice fed a chow diet, Cre induction reduced plasma cholesterol levels from 233.9+/-46.0 to 37.2+/-6.5 mg/dL. In mice fed a high-fat diet, cholesterol levels fell from 525.7+/-32.2 to 100.6+/-14.3 mg/dL. The elimination of hepatic lipoprotein production completely prevented both the development of atherosclerosis and the changes in gene expression that accompany atherogenesis. CONCLUSIONS: We developed mice in which hypercholesterolemia can be reversed with a genetic switch. These mice will be useful for understanding gene-expression changes that accompany the reversal of hypercholesterolemia and atherosclerosis
— id: 37274, year: 2003, vol: 107, page: 1315, stat: Journal Article,

Dietary glycotoxins promote diabetic atherosclerosis in apolipoprotein E-deficient mice
Lin, Reigh-Yi; Choudhury, Robin P; Cai, Weijing; Lu, Min; Fallon, John T; Fisher, Edward A; Vlassara, Helen
2003 Jun;168(2):213-220, Atherosclerosis
Hyperglycemia derived advanced glycation endproducts (AGE) have been implicated in diabetic atherosclerosis (AS) but the role of exogenous (dietary) AGE in the development of this serious complication is not known. This study evaluates the influence of diet-related AGE on AS in genetically hypercholesterolemic apolipoprotein E-deficient (apoE(-/-)), streptozotocin-induced diabetic mice. Diabetic and non-diabetic apoE(-/-) mice (6-8 weeks old) were randomized into either a standard AIN-93G chow (AGE 12,500+/-700 U/mg, termed high-AGE diet, H-AGE), or the same chow having four to fivefold lower AGE level (L-AGE: 2,700+/-830 U/mg) based on ELISA. After 2 months of diabetes, compared to the diabetic mice fed standard (H-AGE) diet, the AS lesions at the aortic root of the L-AGE group were >50% smaller (0.17+/-0.03 vs. 0.31+/-0.05 mm(2), P<0.05). Serum AGE were lower in the diabetic L-AGE than in the H-AGE mice (by approximately 53%) (P<0.00001), as were in the non-diabetic L-AGE vs. H-AGE groups (P<0.05). No diet-related changes were noted in plasma glucose, triglycerides, or plasma cholesterol. Immunohistochemical comparisons showed markedly suppressed tissue AGE, AGE-Receptor-1, -2 and RAGE expression, reduced numbers of inflammatory cells, tissue factor, vascular cell adhesion molecule-1 and MCP-1 in the L-AGE diabetic group. The findings are supportive of an important link between dietary intake of pre-formed glycoxidation products, tissue-incorporated AGE, and diabetes-accelerated AS. The marked anti-atherogenic effects of an AGE-restricted diet in this model may provide the basis for relevant clinical studies
— id: 37272, year: 2003, vol: 168, page: 213, stat: Journal Article,

The inhibition of microsomal triglyceride transfer protein activity in rat hepatoma cells promotes proteasomal and nonproteasomal degradation of apoprotein b100
Cardozo, Christopher; Wu, Xinye; Pan, Meihui; Wang, Hongxing; Fisher, Edward A
2002 Aug 6;41(31):10105-10114, Biochemistry
In the human hepatic cell line, HepG2, apolipoprotein B100 (apoB100) degradation is increased by inhibiting lipid transfer mediated by the microsomal triglyceride transfer protein (MTP) and is predominantly accomplished by the ubiquitin-proteasome pathway. In the current study, we determined whether this degradative pathway was restricted to HepG2 cells or was of more general importance in hepatic apoB100 metabolism. Rat hepatoma McArdle RH7777 cells (McA), compared to HepG2 cells, secrete a large fraction of apoB100 associated with VLDL particles, as does the normal mammalian liver. In McA cells studied under basal conditions, the proteasome inhibitor lactacystin (LAC) increased apoB100 recovery, indicating that the role of the proteasome in apoB100 metabolism is not restricted to HepG2 cells. When apoB100 lipidation was blocked by an inhibitor of MTP (MTPI), recovery of cellular apoB100 was markedly reduced, but LAC was only partially ( approximately 50%) effective in reversing the induced degradation. This partial effectiveness of LAC may have represented either (1) incomplete inhibition by LAC of its preferred target, the chymotrypsin-like activity of the proteasome, (2) the presence of an apoB100 proteolytic activity of the proteasome resistant to LAC, or (3) a nonproteasomal proteolytic pathway of apoB100 degradation. By studying immunoisolated proteasomes and McA cells treated with LAC and/or MTPI and a variety of protease inhibitors, we determined that the proteasomal component of apoB100 degradation was entirely attributable to the chymotrypsin-like catalytic activity, but only accounted for part of apoB100 degradation induced by MTPI. The nonproteasomal apoB100 degradative pathway was nonlysosomal and resistant to E64d, DTT, and peptide aldehydes such as MG132 or ALLN but was partially sensitive to the serine protease inhibitor APMSF. Furthermore, when the protein trafficking inhibitor, brefeldin A, was used to block endoplasmic reticulum (ER) to Golgi transport in MTPI-treated McA cells, degradative activity resistant to LAC was increased, suggesting that the nonproteasomal pathway is associated with the ER
— id: 37280, year: 2002, vol: 41, page: 10105, stat: Journal Article,

Atherosclerotic lesions in genetically modified mice quantified in vivo by non-invasive high-resolution magnetic resonance microscopy
Choudhury, Robin P; Aguinaldo, J Gilberto; Rong, James X; Kulak, Jessica L; Kulak, Amy R; Reis, Ernane D; Fallon, John T; Fuster, Valentin; Fisher, Edward A; Fayad, Zahi A
2002 Jun;162(2):315-321, Atherosclerosis
We have previously shown that magnetic resonance microscopy (MRM) accurately quantifies atherosclerosis in Apolipoprotein E deficient (ApoE(-/-)) mice aged 36-84 weeks. The present study tests MRM in the quantification of aortic atherosclerosis over a broader range of lesion severity. Younger mice with less advanced disease were imaged in order to evaluate sensitivity, specificity and maximum practical resolution of MRM. Nineteen mice underwent in vivo MRM. Wall area measurements by MRM and light microscopy (LM) (n=43) were highly correlated (r=0.85, slope=0.88, P<0.0001). Wall areas by MRM ranged from 0.114 to 0.934 (median, 0.334) mm(2). A threshold of 0.35 mm(2), for the upper limit of normal, gave MRM positive predictive value (PPV) for detecting abnormally thickened arteries=89.5% and negative predictive value (NPV)=75%, referred to LM. Lesion shape assessed by LM and MRM were also well correlated (r=0.72, P<0.001). Increased wall area in atherosclerosis was found by MRM (P=0.01) and LM (P<0.0001) to be accommodated entirely by 'positive remodeling', confirming the importance of determining plaque size directly. MRM accurately quantifies mouse aortic atherosclerosis and will enhance studies in this important animal model
— id: 37285, year: 2002, vol: 162, page: 315, stat: Journal Article,

MRI and characterization of atherosclerotic plaque: emerging applications and molecular imaging
Choudhury, Robin P; Fuster, Valentin; Badimon, Juan J; Fisher, Edward A; Fayad, Zahi A
2002 Jul 1;22(7):1065-1074, Arteriosclerosis, thrombosis, & vascular biology
Noninvasive high-resolution magnetic resonance has the potential to image atherosclerotic plaque and to determine its composition and microanatomy. This review summarizes the rationale for plaque imaging and describes the characteristics of plaque by use of existing MRI techniques. The use of MRI in human disease and in animal models, particularly in rabbits and mice, is presented. Present and future applications of MRI, including real-time vascular intervention, new contrast agents, and molecular imaging, are also discussed
— id: 37281, year: 2002, vol: 22, page: 1065, stat: Journal Article,

Complexity in the secretory pathway: the assembly and secretion of apolipoprotein B-containing lipoproteins
Fisher, Edward A; Ginsberg, Henry N
2002 May 17;277(20):17377-17380, Journal of biological chemistry
— id: 37284, year: 2002, vol: 277, page: 17377, stat: Journal Article,

Improved insulin sensitivity is associated with restricted intake of dietary glycoxidation products in the db/db mouse
Hofmann, Susanna M; Dong, Heng-Jiang; Li, Zhu; Cai, Weijing; Altomonte, Jennifer; Thung, Swan N; Zeng, Feng; Fisher, Edward A; Vlassara, Helen
2002 Jul;51(7):2082-2089, Diabetes
Advanced glycation end products (AGEs), known promoters of diabetic complications, form abundantly in heated foods and are ingested in bioreactive forms. To test whether dietary AGEs play a role in the progression of insulin resistance, C57/BL/KsJ db/db mice were randomly placed for 20 weeks on a diet with either a low AGE content (LAD) or a 3.4-fold higher content of AGE (high AGE diet [HAD]), including (epsilon)N-carboxymethyllysine (CML) and methylglyoxal (MG). LAD-fed mice showed lower fasting plasma insulin levels throughout the study (P = 0.01). Body weight was reduced by approximately 13% compared with HAD-fed mice (P = 0.04) despite equal food intake. LAD-fed mice exhibited significantly improved responses to both glucose (at 40 min, P = 0.003) and insulin (at 60 min, P = 0.007) tolerance tests, which correlated with a twofold higher glucose uptake by adipose tissue (P = 0.02). Compared with the severe hypertrophy and morphological disorganization of islets from HAD-fed mice, LAD-fed mice presented a better-preserved structure of the islets. LAD-fed mice demonstrated significantly increased plasma HDL concentrations (P < 0.0001). Consistent with these observations, LAD-fed mice exhibited twofold lower serum CML and MG concentrations compared with HAD-fed mice (P = 0.02). These results demonstrate that reduced AGE intake leads to lower levels of circulating AGE and to improved insulin sensitivity in db/db mice
— id: 37282, year: 2002, vol: 51, page: 2082, stat: Journal Article,

Effectiveness of tirofiban, eptifibatide, and abciximab in minimizing myocardial necrosis during percutaneous coronary intervention (TEAM pilot study)
Kini, Annapoorna S; Richard, Merwin; Suleman, Javed; Perez, Nohelia; Lee, Paul; Fisher, Edward A; Kamran, Mazullah; Marmur, Jonathan D; Sharma, Samin K
2002 Sep 1;90(5):526-529, American journal of cardiology
— id: 37279, year: 2002, vol: 90, page: 526, stat: Journal Article,

Myristic acid increases dense lipoprotein secretion by inhibiting apoB degradation and triglyceride recruitment
Kummrow, Emma; Hussain, M Mahmood; Pan, Meihui; Marsh, Julian B; Fisher, Edward A
2002 Dec;43(12):2155-2163, Journal of lipid research
Fatty acids of varying lengths and saturation differentially affect plasma apolipoprotein B-100 (apoB-100) levels. To identify mechanisms at the level of production, rat hepatoma cells, McA-RH7777, were incubated with [(35)S]methionine and either fatty acid-BSA complexes or BSA alone. There were increases in labeled apoB-100 secretion with saturated fatty acids palmitic and myristic (MA) (153 +/- 20% and 165 +/- 11%, respectively, relative to BSA). Incubation with polyunsaturated docosahexaenoic acid (DHA) decreased secretion to 26 +/- 2.0%, while monounsaturated oleic acid (OA) did not change it. In pulse-chase studies, MA treatment resulted in reduced apoB-100 degradation, in agreement with its promotion of secretion. In triglyceride (TG) studies, synthesis was stimulated equally by OA, MA, and DHA, but TG secretion was relatively decreased with MA and DHA. With OA, the majority of newly secreted apoB100-lipoproteins was d < or = 1.006, but with MA, they were much denser (1.063 < d). Furthermore, the relative recruitment of newly synthesized TG to lipoproteins was impaired with MA. We conclude that mechanisms for effects of specific dietary fatty acids on plasma lipoprotein levels may include changes in hepatic production. In turn, hepatic production may be regulated by specific fatty acids at the steps of apoB-100 degradation and the recruitment of nascent TG to lipoprotein particles
— id: 37277, year: 2002, vol: 43, page: 2155, stat: Journal Article,

Lowering of dietary advanced glycation endproducts (AGE) reduces neointimal formation after arterial injury in genetically hypercholesterolemic mice
Lin, Reigh-Yi; Reis, Ernane D; Dore, Anthony T; Lu, Min; Ghodsi, Newsha; Fallon, John T; Fisher, Edward A; Vlassara, Helen
2002 Aug;163(2):303-311, Atherosclerosis
Restenosis remains a major cause of morbidity and mortality after coronary angioplasty. Injury-induced inflammation, thrombosis, smooth muscle cell (SMC) proliferation, and neointimal formation contribute to restenosis. These events are linked to circulating glucose-derived advanced gycation endproducts (AGE), known to promote cell proliferation, lipid glycoxidation and oxidant stress. This study evaluates the association between dietary AGE content and neointimal formation after arterial injury in genetically hypercholesterolemic mice. Male, 12-week-old, apolipoprotein E-deficient (apoE(-/-)) mice were randomly assigned to receive either a high AGE diet (HAD; AGE=15000 U/mg), or a similar diet with ten-fold lower AGE (LAD; AGE=1500 U/mg). These mice underwent femoral artery injury 1 week later, and were maintained on their diets for an additional 4 weeks. At 4 weeks after injury, significant decrease in neointimal formation was noted in LAD-fed mice. Neointimal area, intima/media ratio, and stenotic luminal area (LA) were less pronounced in the LAD group than the HAD group (P<0.05). These quantitative differences were associated with a marked reduction ( approximately 56%) of macrophages in the neointimal lesions, as well as an obvious reduction of SMC content of LAD-fed mice. The reduction of neointimal formation in the LAD mice correlated with a approximately 40% decrease in circulating AGE levels (P<0.0005). Immunohistochemistry also showed a reduced ( approximately 1.5-fold) deposition of AGE in the endothelia, SMC, and macrophages in neointimal lesions of LAD-fed mice. These results represent the first evidence in vivo for a causal relationship between dietary AGE and the vessel wall response to acute injury, suggesting a significant potential for dietary AGE restriction in the prevention of restenosis after angioplasty
— id: 37283, year: 2002, vol: 163, page: 303, stat: Journal Article,

The late addition of core lipids to nascent apolipoprotein B100, resulting in the assembly and secretion of triglyceride-rich lipoproteins, is independent of both microsomal triglyceride transfer protein activity and new triglyceride synthesis
Pan, Meihui; Liang Js, Jun-shan; Fisher, Edward A; Ginsberg, Henry N
2002 Feb 8;277(6):4413-4421, Journal of biological chemistry
Although microsomal triglyceride transfer protein (MTP) and newly synthesized triglyceride (TG) are critical for co-translational targeting of apolipoprotein B (apoB100) to lipoprotein assembly in hepatoma cell lines, their roles in the later stages of lipoprotein assembly remain unclear. Using N-acetyl-Leu-Leu-norleucinal to prevent proteasomal degradation, HepG2 cells were radiolabeled and chased for 0-90 min (chase I). The medium was changed and cells chased for another 150 min (chase II) in the absence (control) or presence of Pfizer MTP inhibitor CP-10447 (CP). As chase I was extended, inhibition of apoB100 secretion by CP during chase II decreased from 75.9% to only 15% of control (no CP during chase II). Additional studies were conducted in which chase I was either 0 or 90 min, and chase II was in the presence of [(3)H]glycerol and either BSA (control), CP (inhibits both MTP activity and TG synthesis),BMS-1976360-1) (BMS) (inhibits only MTP activity), or triacsin C (TC) (inhibits only TG synthesis). When chase I was 0 min, CP, BMS, and TC reduced apoB100 secretion during chase II by 75.3, 73.9, and 53.9%. However, when chase I was 90 min, those agents reduced apoB100 secretion during chase II by only 16.0, 19.2, and 13.9%. Of note, all three inhibited secretion of newly synthesized TG during chase II by 80, 80, and 40%, whether chase I was 0 or 90 min. In both HepG2 cells and McA-RH7777 cells, if chase I was at least 60 min, inhibition of TG synthesis and/or MTP activity did not affect the density of secreted apoB100-lipoproteins under basal conditions. Oleic acid increased secretion of TG-enriched apoB100-lipoproteins similarly in the absence or presence of either of CP, BMS, or TC. We conclude that neither MTP nor newly synthesized TG is necessary for the later stages of apoB100-lipoprotein assembly and secretion in either HepG2 or McA-RH7777 cells
— id: 37290, year: 2002, vol: 277, page: 4413, stat: Journal Article,

Lysophosphatidylcholine stimulates monocyte chemoattractant protein-1 gene expression in rat aortic smooth muscle cells
Rong, James X; Berman, Joan W; Taubman, Mark B; Fisher, Edward A
2002 Oct 1;22(10):1617-1623, Arteriosclerosis, thrombosis, & vascular biology
OBJECTIVE: Monocyte chemoattractant protein (MCP)-1 is a proatherogenic factor that is responsible for approximately 60% of plaque macrophages in mouse models of atherosclerosis. We investigated whether lysophosphatidylcholine (LPC), enriched in oxidized low density lipoprotein, can modulate the expression of MCP-1 in arterial wall cells. METHODS AND RESULTS: LPC induced a 3-fold increase in MCP-1 mRNA in rat vascular smooth muscle cells (VSMCs) in a time- and dose-dependent manner. Nuclear runon analysis showed that this increase was attributable to increased MCP-1 gene transcription. There was a 2-fold increase in MCP-1 protein in the conditioned media of cells treated with LPC. LPC-associated increases of MCP-1 mRNA and protein were similar to those produced by platelet-derived growth factor-BB, a known inducer of MCP-1. Analyses of the MCP-1 promoter in transiently transfected VSMCs indicated an LPC-responsive element(s) between base pairs -146 and -261 (relative to transcription initiation). Further studies suggested that LPC-induced MCP-1 expression partially involves mitogen-activated protein kinase/extracellular signal-regulated kinase, a tyrosine kinase(s), and (to a lesser extent) protein kinase C but not the activation of the platelet-derived growth factor receptor. CONCLUSIONS: LPC stimulates MCP-1 expression at the transcriptional level in VSMCs, suggesting a molecular mechanism by which LPC contributes to the atherogenicity of oxidized low density lipoprotein
— id: 37278, year: 2002, vol: 22, page: 1617, stat: Journal Article,

Dyslipidemia in pediatric renal disease: epidemiology, pathophysiology, and management
Saland, Jeffrey M; Ginsberg, Henry; Fisher, Edward A
2002 Apr;14(2):197-204, Current opinion in pediatrics
Dyslipidemia increases the risk of cardiovascular events among individuals with renal disease, and there is a growing body of evidence that it hastens the progression of renal disease itself. Children with nephrotic syndrome or renal transplants have easily recognized hyperlipidemia. Among those with chronic renal insufficiency or end-stage renal disease, detection of dyslipidemia requires more careful analysis and knowledge of normal pediatric ranges. Disordered lipoprotein metabolism results from complex interactions among many factors, including the primary disease process, use of medications such as corticosteroids, the presence of malnutrition or obesity, and diet. The systematic treatment of dyslipidemia in children with chronic renal disease is controversial because conclusive data regarding the risks and benefits are lacking. Hepatic 3-methylglutaryl coenzyme A reductase inhibitors (statins), fibrates, plant stanols, bile acid-binding resins, and dietary manipulation are options for individualized treatment. Prospective investigations are required to guide clinical management
— id: 37286, year: 2002, vol: 14, page: 197, stat: Journal Article,

Laser capture microdissection analysis of gene expression in macrophages from atherosclerotic lesions of apolipoprotein E-deficient mice
Trogan, Eugene; Choudhury, Robin P; Dansky, Hayes M; Rong, James X; Breslow, Jan L; Fisher, Edward A
2002 Feb 19;99(4):2234-2239, Proceedings of the National Academy of Sciences of the United States of America
Macrophage foam cells are integral in the development of atherosclerotic lesions. Gene expression analysis of lesional macrophage foam cells is complicated by the cellular heterogeneity of atherosclerotic plaque and the presence of lesions of various degrees of severity. To overcome these limitations, we tested the ability of laser capture microdissection (LCM) and real-time quantitative reverse transcription PCR to selectively analyze RNA from lesional macrophages of apolipoprotein E (apoE)-deficient mice. Proximal aortic tissue sections were immunostained for macrophagespecific CD68/macrosialin by a rapid (approximately 15-min) protocol. Alternating sections from each animal were used to isolate RNA either from entire sections (analogous to isolation from whole tissue) or by LCM selection of CD68-positive cells. We measured the mRNA levels of CD68, a macrophage-specific marker, alpha-actin, a smooth muscle cell marker, and cyclophilin A, a control gene. Compared with whole sections, CD68 mRNA levels were greatly enriched (33.6-fold) in the laser-captured lesional macrophages. In contrast to whole sections, LCM-derived RNA had undetectable levels of alpha-actin. To illustrate the ability of this method to measure changes in lesional macrophage gene expression, we injected 100 microg of lipopolysaccharide i.p. into apoE-deficient mice and detected in laser-captured lesional macrophages increased mRNA expression for vascular cell adhesion molecule-1, intercellular cell adhesion molecule-1, and monocyte chemoattractant protein-1 (11.9-, 32.5-, and 31.0-fold, respectively). By selectively enriching foam cell RNA, LCM provides a powerful approach to study the in situ expression and regulation of atherosclerosis-related genes. This approach will allow the study of macrophage gene expression under various conditions of plaque formation, regression, and response to genetic and environmental perturbations
— id: 37288, year: 2002, vol: 99, page: 2234, stat: Journal Article,

The triple threat to nascent apolipoprotein B. Evidence for multiple, distinct degradative pathways
Fisher EA; Pan M; Chen X; Wu X; Wang H; Jamil H; Sparks JD; Williams KJ
2001 Jul 27;276(30):27855-27863, Journal of biological chemistry
We previously showed that Omega-3 fatty acids reduce secretion of apolipoprotein B (apoB) from cultured hepatocytes by stimulating post-translational degradation. In this report, we now characterize this process, particularly in regard to the two known processes that degrade newly synthesized apoB, endoplasmic reticulum (ER)-associated degradation and re-uptake from the cell surface. First, we found that Omega-3-induced degradation preferentially reduces the secretion of large, assembled apoB-lipoprotein particles, and apoB polypeptide length is not a determinant. Second, based on several experimental approaches, ER-associated degradation is not involved. Third, re-uptake, the only process known to destroy fully assembled nascent lipoproteins, was clearly active in primary hepatocytes, but Omega-3-induced degradation of apoB continued even when re-uptake was blocked. Cell fractionation showed that Omega-3 fatty acids induced a striking loss of apoB100 from the Golgi, while sparing apoB100 in the ER, indicating a post-ER process. To determine the signaling involved, we used wortmannin, a phosphatidylinositol 3-kinase (PI3K) inhibitor, which blocked most, if not all, of the Omega-3 fatty acid effect. Therefore, nascent apoB is subject to ER-associated degradation, re-uptake, and a third distinct degradative pathway that appears to target lipoproteins after considerable assembly and involves a post-ER compartment and PI3K signaling. Physiologic, pathophysiologic, and pharmacologic regulation of net apoB secretion may involve alterations in any of these three degradative steps
— id: 37295, year: 2001, vol: 276, page: 27855, stat: Journal Article,

AHA Science Advisory. Wine and your heart: A science advisory for healthcare professionals from the Nutrition Committee, Council on Epidemiology and Prevention, and Council on Cardiovascular Nursing of the American Heart Association
Goldberg IJ; Mosca L; Piano MR; Fisher EA
2001 Feb;32(2):591-594, Stroke
— id: 37299, year: 2001, vol: 32, page: 591, stat: Journal Article,

AHA Science Advisory: Wine and your heart: a science advisory for healthcare professionals from the Nutrition Committee, Council on Epidemiology and Prevention, and Council on Cardiovascular Nursing of the American Heart Association
Goldberg IJ; Mosca L; Piano MR; Fisher EA
2001 Jan 23;103(3):472-475, Circulation
— id: 37298, year: 2001, vol: 103, page: 472, stat: Journal Article,

Apoprotein B degradation is promoted by the molecular chaperones hsp90 and hsp70
Gusarova V; Caplan AJ; Brodsky JL; Fisher EA
2001 Jul 6;276(27):24891-24900, Journal of biological chemistry
Apoprotein B (apoB) is the major protein of liver-derived atherogenic lipoproteins. The net production of apoB can be regulated by presecretory degradation mediated by the ubiquitin-proteasome pathway and cytosolic hsp70. To further explore the mechanisms of apoB degradation, we have established a cell-free system in which degradation can be faithfully recapitulated. Human apoB48 synthesized in vitro was translocated into microsomes, glycosylated, and ubiquitinylated. Subsequent incubation with rat hepatic cytosol led to proteasome-mediated degradation. To explore whether hsp90 is required for apoB degradation, geldanamycin (GA) was added during the degradation assay. GA increased the recovery of microsomal apoB48 approximately 3-fold and disrupted the interaction between hsp90 and apoB48. Confirming the hsp90 effect in the cell-free system, we also found that transfection of hsp90 cDNA into rat hepatoma cells enhanced apoB48 degradation. Finally, apoB48 degradation was reconstituted in vitro using cytosol prepared from wild type yeast. Notably, degradation was attenuated when apoB48-containing microsomes were incubated with cytosol supplemented with GA or with cytosol prepared from yeast strains with mutations in the homologues of mammalian hsp70 and hsp90. Overall, our data suggest that hsp90 facilitates the interaction between endoplasmic reticulum-associated apoB and components of the proteasomal pathway, perhaps in cooperation with hsp70
— id: 37294, year: 2001, vol: 276, page: 24891, stat: Journal Article,

Acyl-CoA:cholesterol acyltransferase inhibition reduces atherosclerosis in apolipoprotein E-deficient mice
Kusunoki J; Hansoty DK; Aragane K; Fallon JT; Badimon JJ; Fisher EA
2001 May 29;103(21):2604-2609, Circulation
BACKGROUND:Acyl-COA:cholesterol acyltransferase (ACAT) converts cholesterol to cholesteryl esters. The form of ACAT in macrophages, ACAT1, contributes to foam cell formation in the arterial wall and the development of atherosclerosis. Recent studies in a mouse model of atherosclerosis (the apolipoprotein E [apoE]-deficient mouse), however, have suggested that complete deficiency of ACAT1 activity is not antiatherogenic, in part because of toxicity resulting from adverse effects on tissue cholesterol homeostasis. We have tested whether partial inhibition of ACAT1 and ACAT2 (expressed in liver and intestine) activities reduces atherosclerosis development in apoE-deficient mice and avoids toxicity. Methods and RESULTS:ApoE-deficient mice were maintained for 17 weeks on a Western-type diet without (control) or with the ACAT inhibitor F-1394 (effective against ACAT1 and ACAT2) at doses of either 300 (low) or 900 (high) mg/kg. Intimal lesion area at the aortic sinus in controls was 0.69+/-0.06 mm(2). F-1394 treatment significantly decreased lesional area by 39% (low) or 45% (high). F-1394 treatment also reduced lesional immunostaining for macrophages by 61% (low) or 83% (high). En face analysis showed that surface lipid staining in control aortas was 20.0+/-2.8%; F-1394 treatment reduced this by 46% (low) or 62% (high). There were no obvious signs of systemic or vessel wall toxicity associated with F-1394 treatment. CONCLUSIONS:Partial ACAT inhibition by F-1394 had antiatherogenic effects in apoE-deficient mice that were achieved without obvious toxicity. Partial ACAT inhibition may have therapeutic potential in the clinical treatment of atherosclerosis
— id: 37292, year: 2001, vol: 103, page: 2604, stat: Journal Article,

Co-translational interactions of apoprotein B with the ribosome and translocon during lipoprotein assembly or targeting to the proteasome
Pariyarath R; Wang H; Aitchison JD; Ginsberg HN; Welch WJ; Johnson AE; Fisher EA
2001 Jan 5;276(1):541-550, Journal of biological chemistry
Hepatic lipoprotein assembly and secretion can be regulated by proteasomal degradation of newly synthesized apoB, especially if lipid synthesis or lipid transfer is low. Our previous studies in HepG2 cells showed that, under these conditions, newly synthesized apoB remains stably associated with the endoplasmic reticulum (ER) membrane (Mitchell, D. M., Zhou, M., Pariyarath, R., Wang, H., Aitchison, J. D., Ginsberg, H. N., and Fisher, E. A. (1998) Proc. Natl. Acad. Sci. U. S. A. 95, 14733-14738). We now show that independent of lipid synthesis, apoB chains that appear full-length are, in fact, incompletely translated polypeptides still engaged by the ribosome and associated with the ER translocon. In the presence of active lipid synthesis and transfer, translation and lipoprotein assembly are completed, and the complexes exit the ER. Upon omitting fatty acids from, or adding a microsomal triglyceride transfer protein inhibitor to, culture media to reduce lipid synthesis or transfer, respectively, apoB was degraded while it remained associated with the ER and complexed with cytosolic hsp70 and proteasomes. Thus, unlike other ER substrates of the proteasome, such as major histocompatibility complex class I molecules, apoB does not fully retrotranslocate to the cytosol before entering the ubiquitin-proteasome pathway. Although, upon immunofluorescence, apoB in proteasome-inhibited cells accumulated in punctate structures similar in appearance to aggresomes (cytosolic structures containing molecules irreversibly lost from the secretory pathway), these apoB molecules could be secreted when lipid synthesis was stimulated. The results suggest a model in which 1) apoB translation does not complete until lipoprotein assembly terminates, and 2) assembly with lipids or entry into the ubiquitin-proteasome pathway occurs while apoB polypeptides remain associated with the translocon and attached to the ribosome
— id: 37301, year: 2001, vol: 276, page: 541, stat: Journal Article,

Dramatic remodeling of advanced atherosclerotic plaques of the apolipoprotein E-deficient mouse in a novel transplantation model
Reis ED; Li J; Fayad ZA; Rong JX; Hansoty D; Aguinaldo JG; Fallon JT; Fisher EA
2001 Sep;34(3):541-547, Journal of vascular surgery
OBJECTIVE: Regression of atherosclerotic lesions is an important goal. No extensive experimental evidence shows that it can be achieved for advanced lesions. To study this, we developed a model to maintain a long-term change in the plasma lipoprotein environment of advanced arterial lesions of hyperlipidemic (apolipoprotein E [apoE]-deficient) mice. METHODS: The apoE-deficient mice (plasma total cholesterol of 1334 +/- 219 [+/- SEM] mg/dL) on a typical Western diet for 38 weeks had advanced atherosclerotic lesions (ie, beyond the macrophage foam cell stage) throughout the arterial tree. Lesion-containing thoracic aortas were transplanted (replacing a segment of abdominal aorta) into either apoE-deficient or wild-type (WT) (total cholesterol of 86 +/- 10 mg/dL) recipients. Grafts were harvested after 9 weeks. RESULTS: Compared with pretransplant lesions (area = 0.0892 +/- 0.0179 mm(2)), lesion size tended to increase in apoE-deficient to apoE-deficient grafts (0.2411 +/- 0.0636 mm(2); P =.06), whereas a significant reduction was seen in apoE-deficient to WT grafts (0.0214 +/- 0.0049 mm(2); P <.001). Also, foam cells were absent in apoE-deficient to WT grafts, but abundant in pretransplant lesions and apoE-deficient to apoE-deficient grafts. Grafts were evaluated noninvasively in vivo with magnetic resonance imaging, and wall thickening was detected in the apoE-deficient to apoE-deficient group. CONCLUSIONS: Nearly complete regression of advanced atherosclerotic lesions can be achieved with sustained normalization of the plasma lipoprotein profile. Syngeneic arterial transplantation in mice is a novel and valuable model system for atherosclerosis research; and magnetic resonance imaging can detect differences in characteristics in lesions undergoing regression
— id: 37291, year: 2001, vol: 34, page: 541, stat: Journal Article,

Elevating high-density lipoprotein cholesterol in apolipoprotein E-deficient mice remodels advanced atherosclerotic lesions by decreasing macrophage and increasing smooth muscle cell content
Rong JX; Li J; Reis ED; Choudhury RP; Dansky HM; Elmalem VI; Fallon JT; Breslow JL; Fisher EA
2001 Nov 13;104(20):2447-2452, Circulation
BACKGROUND: HDL cholesterol levels are inversely correlated with coronary heart disease risk in humans, and in animal studies, HDL elevation decreases formation and progression of foam-cell lesions. The potential for HDL to affect preexisting advanced atherosclerotic lesions is not known. To approach this issue, we used a novel mouse aortic transplantation model. METHODS AND RESULTS: ApoE-deficient (EKO) mice were fed a Western-type diet for 6 months, and thoracic aortic segments containing advanced lesions replaced segments of the abdominal aorta of 4-month-old EKO syngeneic mice not expressing (plasma HDL cholesterol approximately 26 mg/dL) or expressing (HDL approximately 64 mg/dL) a human apoAI (hAI) transgene. Both types of recipients had comparable non-HDL cholesterol levels. Five months after transplantation, mice were killed and grafts analyzed. Compared with lesion area in pretransplant mice (0.14+/-0.04 mm(2), mean+/-SEM), there was progression in the EKO recipients (0.39+/-0.06 mm(2), P<0.01). Compared with EKO recipients, hAI/EKO recipients had retarded progression (0.24+/-0.04 mm(2), P<0.05). Immunostaining for CD68 and other macrophage-associated proteins, monocyte chemoattractant protein-1, acyl coenzyme A:cholesterol acyltransferase, and tissue factor, in lesions of pretransplant and EKO recipient mice showed abundant macrophages. In contrast, compared with any other group, lesional macrophage area in hAI/EKO mice decreased >80% (P<0.003), and smooth muscle cell content (alpha-actin staining) increased >300% (P<0.006). The decrease in macrophages and increase in smooth muscle cells was primarily in the superficial subendothelial layer. CONCLUSIONS: Increasing HDL cholesterol levels in EKO mice retards progression of advanced atherosclerotic lesions and remodels them to a more stable-appearing phenotype
— id: 37289, year: 2001, vol: 104, page: 2447, stat: Journal Article,

The level and species of plasma non-esterified fatty acids are not related to elevated plasma apolipoprotein B levels in familial combined hyperlipidemia
Shamir R; Williams KJ; Cortner JL; Hudgins LC; Levine LC; McGee-Harper M; Fisher EA
2001 ;32(5-6):349-363, Journal of medicine (Westbury, NY)
Familial combined hyperlipidemia (FCHL), the leading cause of familial hyperlipidemia with premature coronary artery disease, has been associated with insulin resistance and elevated plasma levels of apolipoproten B (apoB) and non-esterified fatty acids (NEFA). Becaus dietary fats affect plasma cholesterol levels, and specific saturated fatty acids (FA) are particularly potent stimulators in vitro of apoB secretio from hepatocytes, we hypothesized that FCHL patients would exhibit elevations in plasma levels of total FA or specific saturated species. Five families containing 12 FCHL subjects (5 adults, 7 children and 8 normals (5 adults, 3 children) were assessed by dietary, anthropometric, and plasma measurements (glucose, insulin, lipoproteins, total NEFA, and specific FA types). After adjustment of the data for age, gender, and family affiliation, multivariate ANOVA indicated that FCHL was significantly associated with elevated plasma levels of apoB (p = 0.001) and insulin (p< 0.001) and increased body weight (p=0.043). Nevertheless, dietary intakes of total and saturated fat were comparable in the two groups, as were plasma levels of total NEFA and the major saturated species. In a study population possessing the salient features of FCHL, circulating total NEFA were not elevated, nor were specific saturated NEFA that had been associated with apoB oversecretion in vitro. Despite the speculated link between plasma FA and apoB overproduction in FCHL, our data suggest that other metabolic factors underlie this disease
— id: 37287, year: 2001, vol: 32, page: 349, stat: Journal Article,

Atherosclerosis: cell biology and lipoproteins--three distinct processes that control apolipoprotein-B secretion
Williams KJ; Fisher EA
2001 Apr;12(2):235-237, Current opinion in lipidology
— id: 37296, year: 2001, vol: 12, page: 235, stat: Journal Article,

The amino-terminal domain of apolipoprotein B does not undergo retrograde translocation from the endoplasmic reticulum to the cytosol. Proteasomal degradation of nascent apolipoprotein B begins at the carboxyl terminus of the protein, while apolipoprotein B is still in its original translocon
Liang S; Wu X; Fisher EA; Ginsberg HN
2000 Oct 13;275(41):32003-32010, Journal of biological chemistry
We studied the sequential topology of the NH(2) and COOH termini of apoB during translocation by expressing, in Chinese hamster ovary (CHO) and HepG2 cells, an apoB42 construct with c-Myc and hemagglutinin (HA) tags at 2 and 41% (relative to apoB100) of its amino acid sequence. We conducted similar studies using monoclonal antibodies against the NH(2) and COOH termini of apoB100 in HepG2 cells. After radiolabeling, microsomes were immunoisolated from transfected CHO cells using anti-c-Myc or anti-HA antibodies. Throughout a 60-min chase in the presence of N-acetyl-leucyl-norleucinal, more than 90% of microsomes were isolated by anti-HA antibodies, whereas less than 10% were isolated by anti-c-Myc antibodies. Proteinase K digestion of total microsomes consistently generated two fragments ( approximately 70 and approximately 120 kDa) of apoB42 containing the NH(2) terminus throughout the chase; no fragments containing the COOH terminus were detected. Immunofluorescent studies of transfected CHO cells were consistent with results from the labeling studies. Essentially identical results were obtained from pulse-chase studies in both native and apoB42-transfected HepG2 cells. The present studies support a model in which, in the absence of adequate core lipid synthesis, there is partial translocation of apoB leading to cytosolic exposure, ubiquitination, and proteasomal degradation directly from the original translocation channel
— id: 37302, year: 2000, vol: 275, page: 32003, stat: Journal Article,

Inhibition of translocation of nascent apolipoprotein B across the endoplasmic reticulum membrane is associated with selective inhibition of the synthesis of apolipoprotein B
Pan M; Liang J; Fisher EA; Ginsberg HN
2000 Sep 1;275(35):27399-27405, Journal of biological chemistry
In HepG2 cells, inhibition of apolipoprotein B100 (apoB) translocation across the endoplasmic reticulum by an microsomal triglyceride transfer protein (MTP) inhibitor (CP-10447) in the presence of N-acetyl-leucinyl-norleucinal, a proteasomal inhibitor, results in accumulation of newly synthesized apoB in the translocation channel. Here we demonstrated that such accumulation led to a specific reduction of apoB synthesis. ApoB mRNA levels remained unchanged, but we observed reduced rates of elongation of nascent apoB in puromycin-synchronized cells pretreated with MTP inhibitor. This observation was consistent with a longer half-ribosome transit time for the synthesis of apoB in MTP-inhibited cells. Initiation of translation of apoB mRNA was not impaired by MTP inhibition. Overall, these findings suggest that translocation arrest of apoB in the endoplasmic reticulum channel can exert a selective and negative effect on the synthesis of apoB at the stage of elongation
— id: 37304, year: 2000, vol: 275, page: 27399, stat: Journal Article,

Sulindac inhibits neointimal formation after arterial injury in wild-type and apolipoprotein E-deficient mice
Reis ED; Roque M; Dansky H; Fallon JT; Badimon JJ; Cordon-Cardo C; Shiff SJ; Fisher EA
2000 Nov 7;97(23):12764-12769, Proceedings of the National Academy of Sciences of the United States of America
Neointimal hyperplasia is a critical component of restenosis, a major complication of angioplasty and related therapeutic procedures. We studied the effects of hyperlipidemia and the nonsteroidal anti-inflammatory drugs, aspirin (acetyl-salicylic acid; ASA), and sulindac, on neointimal formation in a mouse femoral arterial injury model. At 2 months of age, normolipidemic, wild-type (WT), and hyperlipidemic, apolipoprotein E-deficient (apoE-/-) mice were divided into three treatment groups: Western-type diet (WD), WD + ASA (200 mg/kg food), and WD + sulindac (300 mg/kg food). After 1 week, mice underwent arterial injury and treatments were maintained for 4 weeks. Histomorphometry of the injured arteries showed striking effects of plasma cholesterol levels and drug treatment on neointimal hyperplasia. In the WD or WD + ASA groups, apoE-/- mice had twice the neointimal area than WT mice ( approximately 30,000 vs. 13,000 microm(2) per section; P < 0.0001). Compared with ASA or WD alone, sulindac treatment resulted in approximately 70% (P = 0.0001) and 50% (P = 0.01) reductions in the neointimal area in apoE-/- and WT mice, respectively. ASA, at a dose sufficient to inhibit platelet aggregation, did not affect neointimal formation in mice of either genotype. Evidence of macrophages was noted in the lesions of apoE-/- mice in the WD and WD + ASA groups, but remarkably, none was detectable with sulindac treatment, despite hyperlipidemia, suggesting early steps in the response to injury were abrogated. These results demonstrate sulindac reduces neointimal formation in both normolipidemic and hyperlipidemic settings and raise the possibility that similar benefits may be obtained in patients undergoing angioplasty and related procedures
— id: 37300, year: 2000, vol: 97, page: 12764, stat: Journal Article,

High-density lipoprotein: gene-based approaches to the prevention of atherosclerosis
Rong JX; Fisher EA
2000 Dec;32(9):642-651, Annals of medicine (Helsinki)
Although the atheroprotective role of high-density lipoprotein (HDL) has been well documented in epidemiological and animal studies, highly effective therapeutic approaches for the selective increase of plasma HDL levels or function are not yet available. Several mechanisms by which HDL exerts an atheroprotective effect have been proposed on the basis of experiments in vitro and in vivo. These mechanisms include directing excess cellular cholesterol from the peripheral tissues to the liver in 'reverse cholesterol transport', inhibiting oxidative modification or aggregation of LDL, and modulating inflammatory responses to favour vasoprotection. This review gives an overview of the genes regulating these mechanisms, such as those encoding apolipoprotein AI, lecithin:cholesterol acyltransferase (LCAT), scavenger receptor B1 (SR-BI), and the ATP-binding cassette transporter 1 (ABC1), and the potential to exploit them to develop gene-based therapeutic approaches to increase the level or function of HDL
— id: 37297, year: 2000, vol: 32, page: 642, stat: Journal Article,

Release of active tissue factor by human arterial smooth muscle cells
Schecter AD; Spirn B; Rossikhina M; Giesen PL; Bogdanov V; Fallon JT; Fisher EA; Schnapp LM; Nemerson Y; Taubman MB
2000 Jul 21;87(2):126-132, Circulation research
Tissue factor (TF), the initiator of coagulation, is thought to function predominantly at the cell surface. Recent data have suggested that active TF is present extracellularly in atherosclerotic plaques, the arterial wall, and the blood. This study was conducted to determine whether smooth muscle cells (SMCs), a major source of arterial TF, could generate extracellular TF. Active TF accumulated in the medium of cultured human SMCs, representing approximately 10% of that measured in the underlying cells at 24 hours. Platelet-derived growth factor, phorbol ester, and tumor necrosis factor-alpha caused approximately 3-fold increases in TF activity in the medium. Release of TF into the medium was dependent on the presence of the TF transmembrane domain but not the cytoplasmic domain. Antibodies to TF precipitated most of the activity from the culture medium, whereas antibodies to the beta(1)-integrin subunit precipitated approximately 33% of the activity. Treatment with detergent or phosphatidylserine:phosphatidylcholine did not increase activity, suggesting that all TF released by SMCs was in the appropriate lipid milieu and not encrypted. Western blotting showed that the medium contained full-length TF protein. Fluorescent cytometry showed that extracellular TF was present largely in particles < or =200 nm, which had a density of 1.10 g/mL. We hypothesize that active extracellular TF found in the injured arterial wall and atherosclerotic plaques derives, in part, from SMC microparticles
— id: 37303, year: 2000, vol: 87, page: 126, stat: Journal Article,

Dietary therapy for children with hypercholesterolemia
Shamir R; Fisher EA
2000 Feb 1;61(3):675-82, 685, American family physician
Accumulating evidence clearly shows that atherosclerosis begins in youth. The National Cholesterol Education Program (NCEP) has recommended that children at high risk of developing coronary artery disease as adults be screened so that those with elevated low-density lipoprotein (LDL) cholesterol levels can be treated, primarily by modification of diet. The initial approach to these youthful patients is to use the NCEP step I diet. This diet provides calories and nutrients that support normal growth and development, but limits saturated fat and total fat intake to no more than 10 and 30 percent of total calories, respectively, and cholesterol intake to no more than 100 mg per 1,000 kcal per day, to a maximum of 300 mg. If the goal of reducing the LDL cholesterol level to below 130 mg per dL (3.35 mmol per L) is not achieved, the more restrictive step II diet should be initiated. However, the step II diet may not provide sufficient calories and nutrients to support normal growth and development; therefore, trained nutritionists may be required to effectively manage a child on this diet
— id: 37306, year: 2000, vol: 61, page: 675, stat: Journal Article,

Hypercholesterolemia in children
Shamir R; Lerner A; Fisher EA
2000 Oct;2(10):767-771, Israel Medical Association journal
— id: 37293, year: 2000, vol: 2, page: 767, stat: Journal Article,

Hydrolysis of retinyl esters by pancreatic triglyceride lipase
van Bennekum AM; Fisher EA; Blaner WS; Harrison EH
2000 Apr 25;39(16):4900-4906, Biochemistry
Previously [van Bennekum, A. M., et al. (1999) Biochemistry 38, 4150-4156] we showed that carboxyl ester lipase (CEL)-deficient (CELKO) mice have normal levels of pancreatic, bile salt-dependent retinyl ester hydrolase (REH) activity. In the present study, we further investigated this non-CEL REH activity in pancreas homogenates of CELKO and wild-type (WT) mice, and rats. REH activity was detected in both the presence and absence of tri- and dihydroxy bile salts in rats, WT mice, and CELKO mice. In contrast, pancreatic cholesteryl ester hydrolase (CEH) activity was only detected in the presence of trihydroxy bile salts and only in rats and WT mice, consistent with CEL-mediated cholesteryl ester hydrolysis. Enzyme assays of pancreatic triglyceride lipase (PTL) showed that there was a colipase-stimulated REH activity in rat and mouse (WT and CELKO) pancreas, consistent with hydrolysis of retinyl ester (RE) by PTL. Pancreatic enzyme activities related to either CEL or PTL were separated using DEAE-chromatography. In both rats and mice (WT and CELKO), REH activity could be attributed mainly to PTL, and to a much smaller extent to CEL. Finally, purified human PTL exhibited similar enzymatic characteristics for triglyceride hydrolysis as well as for retinyl ester hydrolysis, indicating that RE is a substrate for PTL in vivo. Altogether, these studies clearly show that PTL is the major pancreatic REH activity in mice, as well as in rats
— id: 37305, year: 2000, vol: 39, page: 4900, stat: Journal Article,

High-density lipoprotein and plaque regression: the good cholesterol gets even better
Dansky HM; Fisher EA
1999 Oct 26;100(17):1762-1763, Circulation
— id: 37308, year: 1999, vol: 100, page: 1762, stat: Journal Article,

Summary of a scientific conference on preventive nutrition: pediatrics to geriatrics
Deckelbaum RJ; Fisher EA; Winston M; Kumanyika S; Lauer RM; Pi-Sunyer FX; St Jeor S; Schaefer EJ; Weinstein IB
1999 Jul 27;100(4):450-456, Circulation
— id: 37309, year: 1999, vol: 100, page: 450, stat: Journal Article,

Intraatrial mitral valve insertion with native valve preservation in children
DeLeon SY; Cetta F; Ravindranath TM; Roughneen PT; Fisher EA
1999 Nov;68(5):1843-1845, Annals of thoracic surgery
Two patients underwent intraatrial mitral valve insertion for an unsuccessful valvotomy for severe mitral stenosis and left-sided atrioventricular valve insufficiency associated with corrected transposition utilizing a porcine valve from a valved conduit with preservation of the native valve. The valves were inserted using continuous suture distally at the mitral annulus and proximally at the pulled atrial wall distal to the pulmonary veins. Both patients had uneventful hospital course and are doing well at up to 6 months postoperatively. This approach provides a viable option for congenital mitral stenosis or insufficiency in children
— id: 37307, year: 1999, vol: 68, page: 1843, stat: Journal Article,

Carboxyl ester lipase overexpression in rat hepatoma cells and CEL deficiency in mice have no impact on hepatic uptake or metabolism of chylomicron-retinyl ester
van Bennekum AM; Li L; Piantedosi R; Shamir R; Vogel S; Fisher EA; Blaner WS; Harrison EH
1999 Mar 30;38(13):4150-4156, Biochemistry
To study the role of carboxyl ester lipase (CEL) in hepatic retinoid (vitamin A) metabolism, we investigated uptake and hydrolysis of chylomicron (CM)-retinyl esters (RE) by rat hepatoma (McArdle-RH7777) cells stably transfected with a rat CEL cDNA. We also studied tissue uptake of CM-RE in CEL-deficient mice generated by targeted disruption of the CEL gene. CEL-transfected cells secreted active enzyme into the medium. However, both control and CEL-transfected cells accumulated exogenously added CM-RE or CM remnant (CMR)-derived RE in equal amounts. Serum clearance of intravenously injected CM-RE and cholesteryl ester were not different between wild-type and CEL-deficient mice. Also, the uptake of the two compounds by the liver and other tissues did not differ. These data indicate that the lack of CEL expression does not affect the uptake of dietary CM-RE by the liver or other tissues. Moreover, the percentage of retinol formed in the liver after CM-RE uptake, the levels of retinol and retinol-binding protein in serum, and retinoid levels in various tissues did not differ, indicating that CEL deficiency does not affect hepatic retinoid metabolism and retinoid distribution throughout the body. Surprisingly, in both pancreas and liver of wild-type, heterozygous, and homozygous CEL-deficient mice, the levels of bile salt-dependent retinyl ester hydrolase (REH) activity were similar. This indicates that in the mouse pancreas and liver an REH enzyme activity, active in the presence of bile salt and distinct from CEL, is present, compatible with the results from our accompanying paper that the intestinal processing and absorption of RE were unimpaired in CEL-deficient mice
— id: 37310, year: 1999, vol: 38, page: 4150, stat: Journal Article,

Intestinal absorption of dietary cholesteryl ester is decreased but retinyl ester absorption is normal in carboxyl ester lipase knockout mice
Weng W; Li L; van Bennekum AM; Potter SH; Harrison EH; Blaner WS; Breslow JL; Fisher EA
1999 Mar 30;38(13):4143-4149, Biochemistry
Carboxyl ester lipase (CEL; EC 3.1.1.13) hydrolyzes cholesteryl esters and retinyl esters in vitro. In vivo, pancreatic CEL is thought to liberate cholesterol and retinol from their esters prior to absorption in the intestine. CEL is also a major lipase in the breast milk of many mammals, including humans and mice, and is thought to participate in the processing of triglycerides to provide energy for growth and development while the pancreas of the neonate matures. Other suggested roles for CEL include the direct facilitation of the intestinal absorption of free cholesterol and the modification of plasma lipoproteins. Mice with different CEL genotypes [wild type (WT), knockout (CELKO), heterozygote] were generated to study the functions of CEL in a physiological system. Mice grew and developed normally, independent of the CEL genotype of the pup or nursing mother. Consistent with this was the normal absorption of triglyceride in CELKO mice. The absorption of free cholesterol was also not significantly different between CELKO (87 +/- 26%, mean +/- SD) and WT littermates (76 +/- 10%). Compared to WT mice, however, CELKO mice absorbed only about 50% of the cholesterol provided as cholesteryl ester (CE). There was no evidence for the direct intestinal uptake of CE or for intestinal bacterial enzymes that hydrolyze it, suggesting that another enzyme besides CEL can hydrolyze dietary CE in mice. Surprisingly, CELKO and WT mice absorbed similar amounts of retinol provided as retinyl ester (RE). RE hydrolysis, however, was required for absorption, implying that CEL was not the responsible enzyme. The changes in plasma lipid and lipoprotein levels to diets with increasing lipid content were similar in mice of all three CEL genotypes. Overall, the data indicate that in the mouse, other enzymes besides CEL participate in the hydrolysis of dietary cholesteryl esters, retinyl esters, and triglycerides
— id: 37311, year: 1999, vol: 38, page: 4143, stat: Journal Article,

Anomalous right coronary artery from the pulmonary artery in Taussig-Bing anomaly
Eidem BW; Cetta F; Roughneen PT; DeLeon SY; Fisher EA
1998 Nov;66(5):1797-1798, Annals of thoracic surgery
The presence of associated anomalies in patients with double-outlet right ventricle can significantly alter surgical intervention. Preoperative delineation of these anomalies can facilitate surgical planning and improve outcome. We describe a case in which the right coronary artery and anterior descending coronary artery arose from the pulmonary artery in a patient with double-outlet right ventricle with subpulmonary ventricular septal defect (Taussig-Bing anomaly). Recognition of this important anomaly prevented significant intraoperative myocardial damage by altering techniques of cardioplegia administration for myocardial preservation
— id: 37312, year: 1998, vol: 66, page: 1797, stat: Journal Article,

Noninvasive In vivo high-resolution magnetic resonance imaging of atherosclerotic lesions in genetically engineered mice
Fayad ZA; Fallon JT; Shinnar M; Wehrli S; Dansky HM; Poon M; Badimon JJ; Charlton SA; Fisher EA; Breslow JL; Fuster V
1998 Oct 13;98(15):1541-1547, Circulation
BACKGROUND: The pathogenesis of atherosclerosis is currently being investigated in genetically engineered small animals. Methods to follow the time course of the developing pathology and/or the responses to therapy in vivo are limited. METHODS and RESULTS: To address this problem, we developed a noninvasive MR microscopy technique to study in vivo atherosclerotic lesions (without a priori knowledge of the lesion location or lesion type) in live apolipoprotein E knockout (apoE-KO) mice. The spatial resolution was 0.0012 to 0.005 mm3. The lumen and wall of the abdominal aorta and iliac arteries were identified on all images in apoE-KO (n=8) and wild-type (n=5) mice on chow diet. Images obtained with MR were compared with corresponding cross-sectional histopathology (n=58). MR accurately determined wall area in comparison to histopathology (slope=1.0, r=0.86). In addition, atherosclerotic lesions were characterized in terms of lesion shape and type. Lesion type was graded by MR according to morphological appearance/severity and by histopathology according to the AHA classification. There was excellent agreement between MR and histopathology in grading of lesion shape and type (slope=0.97, r=0.91 for lesion shape; slope=0. 64, r=0.90 for lesion type). CONCLUSIONS: The combination of high-resolution MR microscopy and genetically engineered animals is a powerful tool to investigate serially and noninvasively the progression and regression of atherosclerotic lesions in an intact animal model and should greatly enhance basic studies of atherosclerotic disease
— id: 37314, year: 1998, vol: 98, page: 1541, stat: Journal Article,

Apoprotein B100 has a prolonged interaction with the translocon during which its lipidation and translocation change from dependence on the microsomal triglyceride transfer protein to independence
Mitchell DM; Zhou M; Pariyarath R; Wang H; Aitchison JD; Ginsberg HN; Fisher EA
1998 Dec 8;95(25):14733-14738, Proceedings of the National Academy of Sciences of the United States of America
When lipid synthesis is limited in HepG2 cells, apoprotein B100 (apoB100) is not secreted but rapidly degraded by the ubiquitin-proteasome pathway. To investigate apoB100 biosynthesis and secretion further, the physical and functional states of apoB100 destined for either degradation or lipoprotein assembly were studied under conditions in which lipid synthesis, proteasomal activity, and microsomal triglyceride transfer protein (MTP) lipid-transfer activity were varied. Cells were pretreated with a proteasomal inhibitor (which remained with the cells throughout the experiment) and radiolabeled for 15 min. During the chase period, labeled apoB100 remained associated with the microsomes. Furthermore, by crosslinking sec61beta to apoB100, we showed that apoB100 remained close to the translocon at the same time apoB100-ubiquitin conjugates could be detected. When lipid synthesis and lipoprotein assembly/secretion were stimulated by adding oleic acid (OA) to the chase medium, apoB100 was deubiquitinated, and its interaction with sec61beta was disrupted, signifying completion of translocation concomitant with the formation of lipoprotein particles. MTP participates in apoB100 translocation and lipoprotein assembly. In the presence of OA, when MTP lipid-transfer activity was inhibited at the end of pulse labeling, apoB100 secretion was abolished. In contrast, when the labeled apoB100 was allowed to accumulate in the cell for 60 min before adding OA and the inhibitor, apoB100 lipidation and secretion were no longer impaired. Overall, the data imply that during most of its association with the endoplasmic reticulum, apoB100 is close to or within the translocon and is accessible to both the ubiquitin-proteasome and lipoprotein-assembly pathways. Furthermore, MTP lipid-transfer activity seems to be necessary only for early translocation and lipidation events
— id: 37313, year: 1998, vol: 95, page: 14733, stat: Journal Article,

Modified Konno-Rastan procedure for subaortic stenosis: indications, operative techniques, and results
Roughneen PT; DeLeon SY; Cetta F; Vitullo DA; Bell TJ; Fisher EA; Blakeman BP; Bakhos M
1998 May;65(5):1368-1375, Annals of thoracic surgery
BACKGROUND: Diffuse or unresectable subaortic stenosis (SAS) necessitates an aggressive surgical approach for the elimination of left ventricular outflow tract obstruction. In this article we report our experience with the modified Konno-Rastan procedure, with inherent preservation of the native aortic valve and annulus, in the treatment of diffuse or unresectable SAS. METHODS: Sixteen children (age range, 21 months to 18 years) underwent the modified Konno-Rastan procedure through either a transventricular (n = 12) or a transatrial approach (n = 4) to the conal septum. Indications for operation were recurrent SAS (n = 3), hypertrophic obstructive cardiomyopathy (n = 3), tunnel stenosis (n = 2), SAS related to a canal (n = 3), and SAS after ventricular septal defect closure (n = 5). Eleven patients had undergone previous procedures and 5 underwent the modified Konno-Rastan procedure as their primary operation. RESULTS: The mean preoperative left ventricular outflow tract gradient of 50 +/- 17 mm Hg was reduced to 3 +/- 7 mm Hg (p < 0.001) after surgical repair. Postoperative complications included sternal infection (n = 1), heart block (n = 2), mediastinal bleeding (n = 1), and renal and cerebral ischemia (n = 1). There was 1 late postoperative death caused by pneumonia 2 years after operation (6.2% mortality rate). The mean follow-up period was 62 +/- 39 months and all patients had complete relief of preoperative symptoms and were in New York Heart Association class I. One patient underwent a successful redo modified Konno-Rastan procedure 7 years after the first operation for residual left ventricular outflow tract obstruction immediately below the aortic valve. One patient is awaiting reoperation for aortic incompetence unrelated to conal enlargement 1.5 years after the first procedure. CONCLUSIONS: The modified Konno-Rastan procedure represents an excellent therapy for diffuse or unresectable SAS in patients with a normal aortic valve. In addition, it produces excellent results in a limited number of patients with hypertrophic obstructive cardiomyopathy, in whom the Morrow procedure traditionally has been performed. Although it usually is performed through a transventricular approach, the modified Konno-Rastan procedure also can be performed through a transatrial approach; this is particularly useful in patients who have had previous ventricular septal defect closure associated with SAS occurring proximal to the prosthetic patch
— id: 37316, year: 1998, vol: 65, page: 1368, stat: Journal Article,

The full induction of human apoprotein A-I gene expression by the experimental nephrotic syndrome in transgenic mice depends on cis-acting elements in the proximal 256 base-pair promoter region and the trans-acting factor early growth response factor 1
Zaiou M; Azrolan N; Hayek T; Wang H; Wu L; Haghpassand M; Cizman B; Madaio MP; Milbrandt J; Marsh JB; Breslow JL; Fisher EA
1998 Apr 15;101(8):1699-1707, Journal of clinical investigation
To identify molecular factors regulating apo A-I production in vivo, we induced in transgenic mice the experimental nephrotic syndrome, which results in elevated levels of HDL cholesterol (HDL-C), plasma apo A-I, and hepatic apo A-I mRNA. Human (h) apo A-I transgenic mice with different length 5' flanking sequences (5.5 or 0.256 kb, the core promoter for hepatic-specific basal expression) were injected with nephrotoxic (NTS) or control serum. With nephrosis, there were comparable (greater than twofold) increases in both lines of HDL-C, h-apo A-I, and hepatic h-apo A-I mRNA, suggesting that cis-acting elements regulating induced apo A-I gene expression were within its core promoter. Hepatic nuclear extracts from control and nephrotic mice footprinted the core promoter similarly, implying that the same elements regulated basal and induced expression. Hepatic mRNA levels for hepatocyte nuclear factor (HNF) 4 and early growth response factor (EGR) 1, trans-acting factors that bind to the core promoter, were measured: HNF4 mRNA was not affected, but that of EGR-1 was elevated approximately fivefold in the nephrotic group. EGR-1 knockout (EGR1-KO) mice or mice expressing EGR-1 were injected with either NTS or control serum. Levels of HDL-C, apo A-I, and hepatic apo A-I mRNA were lowest in nonnephrotic EGR1-KO mice and highest in nephrotic mice expressing EGR-1. Although in EGR1-KO mice HDL-C, apo A-I, and apo A-I mRNA levels also increased after NTS injection, they were approximately half of those in the nephrotic EGR-1-expressing mice. We conclude that in this model, basal and induced apo A-I gene expression in vivo are regulated by the trans-acting factor EGR-1 and require the same cis-acting elements in the core promoter
— id: 37317, year: 1998, vol: 101, page: 1699, stat: Journal Article,

Regulated Co-translational ubiquitination of apolipoprotein B100. A new paradigm for proteasomal degradation of a secretory protein
Zhou M; Fisher EA; Ginsberg HN
1998 Sep 18;273(38):24649-24653, Journal of biological chemistry
Presentation of a wild-type secretory protein, apolipoprotein B100 (apoB), to the cytosol for ubiquitin-proteasome proteolysis has been observed in HepG2 cells. A currently accepted model for proteasomal degradation of secretory proteins is retrograde translocation of the substrate polypeptides from the lumen of endoplasmic reticulum (ER) back to the cytosol. In this report, we present evidence that newly synthesized apoB becomes exposed to the cytosol and targeted to the proteasomes in a co-translational manner. Thus, after protein translation was synchronized with puromycin, partially synthesized apoB polypeptides were found to be conjugated to ubiquitin. The magnitude of co-translational ubiquitination and subsequent degradation of apoB was increased when cells were pretreated with either herbimycin A to induce cytosolic Hsp70 or with an inhibitor of microsomal triglyceride transfer protein; both treatments impede translocation of nascent apoB across the ER membrane. These treatments also decreased secretion of apoB and increased its degradation via the ubiquitin-proteasome pathway. We suggest that translocation arrest with subsequent co-translational exposure to the cytosol provides an alternative model to explain how mammalian secretory proteins can overcome topological segregation by the ER membrane and undergo degradation by the ubiquitin-proteasome pathway
— id: 37315, year: 1998, vol: 273, page: 24649, stat: Journal Article,

O-Glycosylation of C-terminal tandem-repeated sequences regulates the secretion of rat pancreatic bile salt-dependent lipase
Bruneau N; Nganga A; Fisher EA; Lombardo D
1997 Oct 24;272(43):27353-27361, Journal of biological chemistry
Amino acid sequences rich in Pro, Glu, Ser, and Thr (PEST) are common to rapidly degraded proteins (Rogers, S., Wells, R. & Rechsteiner, M. (1986) Science 234, 364-368). On pancreatic bile salt-dependent lipase (BSDL), PEST sequences are present in the C-terminal region of the enzyme to which is associated the O-glycosylation. We have postulated that the O-glycosylation of BSDL may contribute to mask PEST sequences and to trigger the secretion of this enzyme instead of its delivery into a degradative pathway (Bruneau, N., and Lombardo, D. (1995) J. Biol. Chem. 270, 13524-13523). To further examine the role of the O-linked glycosylation on BSDL metabolism, rat pancreatic BSDL cDNA was stably transfected into two Chinese hamster ovary (CHO) cell lines, the CHO K1 wild-type line and the O-glycosylation defective CHO ldlD line. In these latter cells, O-glycosylation can be reversibly modulated by culture conditions. Results indicate that the rate of BSDL synthesis by transfected CHO K1 or CHO ldlD cells reflects, independently of culture conditions, the amount of mRNA specific for BSDL present in these transfected cells. Nevertheless, the rate of secretion of the enzyme depends upon cell culture conditions and increases with the cell capability to O-glycosylate C-terminal tandem-repeated sequences. Immunoprecipitation experiments performed on cell lysates suggested that a rapid degradation of BSDL occurred particularly when transfected CHO ldlD cells were cultured under non-permissive conditions. We further showed that BSDL secreted by CHO ldlD cells grown under non-permissive conditions that normally prevent O-glycosylation incorporated galactose and was reactive with peanut agglutinin, which recognizes the core structure of O-linked glycans. We concluded that the BSDL expressed by CHO ldlD cells grown under non-permissive conditions was rapidly degraded but a fraction of the enzyme was allowed to O-glycosylate and consequently was secreted
— id: 37318, year: 1997, vol: 272, page: 27353, stat: Journal Article,

Cost-effectiveness of transaxillary muscle-sparing same-day operative closure of patent ductus arteriosus
Cetta F; Deleon SY; Roughneen PT; Graham LC; Lichtenberg RC; Bell TJ; Vitullo DA; Fisher EA
1997 May 1;79(9):1281-1282, American journal of cardiology
Transaxillary muscle-sparing patent ductus arteriosus closure performed as same-day surgery is described in 10 patients. This approach provides a superb cosmetic result while obviating the need for thoracostomy tube placement
— id: 37324, year: 1997, vol: 79, page: 1281, stat: Journal Article,

Molecular cloning of the cDNA for rat hepatic, bile salt-dependent cholesteryl ester/retinyl ester hydrolase demonstrates identity with pancreatic carboxylester lipase
Chen X; Harrison EH; Fisher EA
1997 Jun;215(2):186-191, Proceedings of the Society for Experimental Biology & Medicine
Rat liver homogenates contain a neutral lipid ester hydrolase that requires millimolar concentrations of bile salts for maximal activity in catalyzing the hydrolysis of cholesteryl esters and retinyl esters in vitro. Previous studies have demonstrated that this hepatic hydrolase resembles rat pancreatic carboxylester lipase because it reacts with a specific pancreatic carboxylester lipase antibody and the eight N-terminal amino acids of the hepatic protein are identical to those of the pancreatic enzyme. Nonetheless, the exact molecular relationship between the hepatic and pancreatic enzymes is unclear. In the present study, a rat hepatic cDNA encoding the enzyme was cloned. Sequence analysis demonstrated that this cDNA corresponds to the full-length mature pancreatic carboxylester lipase (EC# 3.1.1.13). In individual animals the hepatic and pancreatic cDNA sequences were identical. However, among rats there were sequence variations, suggesting a polymorphic nature for this rat gene
— id: 37322, year: 1997, vol: 215, page: 186, stat: Journal Article,

Management of arch hypoplasia after successful coarctation repair
DeLeon MM; DeLeon SY; Quinones JA; Roughneen PT; Magliato KE; Vitullo DA; Cetta F; Bell TJ; Fisher EA
1997 Apr;63(4):975-980, Annals of thoracic surgery
BACKGROUND: Pronounced arch obstruction can be seen after a well-repaired coarctation, and this probably results from the failure of a somewhat hypoplastic arch to grow or from clamp injury at the time of the initial repair, or from both causes. Because of mediastinal adhesions and minimal collateral circulation, use of extraanatomic bypass grafts appears to be the preferred approach. METHODS: Six children or young adults presented with arch obstruction over a 3-year period. Their mean age was 13.5 +/- 4 years, and the mean interval from the time of the initial repair was 10 +/- 4 years. The mean age of the patients at the time of the initial repair was 3.2 +/- 5 years. Symptoms included exertional headache and chest pain. The mean systolic gradients, as shown by echocardiography and cardiac catheterization, were 34 +/- 7 mm Hg and 33 +/- 6 mm Hg, respectively. Repair was accomplished through a midsternotomy using a polytetrafluoroethylene patch placed in the concavity of the arch, which extended from the ascending to the descending aorta. Dissection was kept close to the aorta and arch to minimize injury to the phrenic and recurrent laryngeal nerves. Cardiopulmonary bypass and moderate hypothermia (25 degrees to 27 degrees C bladder temperature) without circulatory arrest were used. RESULTS: All patients were discharged home 4 to 20 days postoperatively (mean, 7 +/- 6 days). All patients were found to be normotensive at a mean follow-up of 1.3 +/- 1 years. Postoperative echocardiograms, which were obtained in all patients, revealed no residual gradients. Exercise blood pressure was evaluated in 2 patients and found to be normal. CONCLUSIONS: Transsternal arch enlargement using cardiopulmonary bypass and moderate hypothermia without circulatory arrest is an attractive and safe approach for the treatment of arch obstruction after coarctation repair. Unlike the use of extraanatomic bypass grafts, it allows complete relief of the obstruction, unhampered aortic growth, the minimal use of foreign material, and a repair that is protected deep within the mediastinal space
— id: 37326, year: 1997, vol: 63, page: 975, stat: Journal Article,

Recognition and management of obstructed pulmonary veins draining to the coronary sinus
DeLeon MM; DeLeon SY; Roughneen PT; Bell TJ; Vitullo DA; Cetta F; Lagamayo L; Fisher EA
1997 Mar;63(3):741-744, Annals of thoracic surgery
BACKGROUND: Obstruction of the pulmonary veins in total anomalous pulmonary venous drainage to the coronary sinus is generally considered rare. However, if it is present, the usual treatment of unroofing the coronary sinus will lead to a poor result. METHODS: Four patients with total anomalous pulmonary venous drainage to the coronary sinus with obstruction were identified over a 14-month period. Three patients in whom the diagnosis of obstruction was not made underwent coronary sinus unroofing. Retrospective review of the preoperative echocardiograms and Doppler studies showed the presence of obstruction in the vertical vein in 2 patients and in the branches in the other. In the fourth patient, obstruction in the vertical vein was recognized preoperatively with echocardiography and Doppler study. This patient underwent direct common pulmonary vein-left atrial anastomosis. RESULTS: All 3 patients who had coronary unroofing were seen with obstructed pulmonary veins 2 to 7 months postoperatively. After reoperation, 1 died, and the other 2 have done relatively well 3 1/2 and 15 months postoperatively. The patient who had an anastomosis between the common pulmonary vein and the left atrium is doing well 18 months postoperatively. CONCLUSIONS: Obstruction in total anomalous pulmonary venous drainage to the coronary sinus is not as rare as previously reported. To improve outcome, its presence should be sought using complete echocardiography including Doppler studies. When obstruction is present, transection of the vertical vein and common pulmonary vein-left atrial anastomosis through the superior approach is an attractive technique that also eliminates the right-to-left shunting associated with coronary sinus unroofing and simplifies closure of the atrial septal defect
— id: 37327, year: 1997, vol: 63, page: 741, stat: Journal Article,

Nutrition and children. A statement for healthcare professionals from the Nutrition Committee, American Heart Association
Fisher EA; Van Horn L; McGill HC Jr
1997 May 6;95(9):2332-2333, Circulation
— id: 37323, year: 1997, vol: 95, page: 2332, stat: Journal Article,

The degradation of apolipoprotein B100 is mediated by the ubiquitin-proteasome pathway and involves heat shock protein 70
Fisher EA; Zhou M; Mitchell DM; Wu X; Omura S; Wang H; Goldberg AL; Ginsberg HN
1997 Aug 15;272(33):20427-20434, Journal of biological chemistry
Apolipoprotein B (apoB) is the major protein component of atherogenic lipoproteins of hepatic origin. In HepG2 cells, the standard cell culture model of human hepatic lipoprotein metabolism, there is a limited availability of core lipids in the endoplasmic reticulum for association with nascent apoB. Under these conditions, apoB is partially translocated, interacts with cytosolic Hsp70, and undergoes rapid degradation. We show that increasing the expression of Hsp70 in HepG2 cells promotes apoB degradation. In addition, apoB is polyubiquitinated and its degradation both normally and after Hsp70 induction is blocked by inhibitors of the proteasome. The apoB that accumulates after proteasome inhibition is endoplasmic reticulum-associated and can be assembled into lipoproteins and secreted if new lipid synthesis is stimulated. Thus, apoB is the first example of a wild-type mammalian protein whose secretion is regulated by degradation in the cytosol via the ubiquitin-proteasome pathway. Furthermore, targeting of this secretory protein to the proteasome is regulated by the molecular chaperone Hsp70 and the availability of apoB's lipid-ligands
— id: 37321, year: 1997, vol: 272, page: 20427, stat: Journal Article,

Histopathologic and biochemical changes in the muscles affected by distraction osteogenesis of the mandible
Fisher, E; Staffenberg, D A; McCarthy, J G; Miller, D C; Zeng, J
1997 Feb;99(2):366-371, Plastic & reconstructive surgery
Lengthening of the canine mandible using an intraoral distraction device was performed in order to study the effects of distraction on the associated muscles of mastication. Biopsies of the masseter and digastric muscles were taken after lengthening at four different time intervals to assess the temporal changes in the masticatory muscles of 10 dogs. Biopsies of the muscles on the contralateral side also were taken from 6 of these dogs before lengthening to establish a control group. Each biopsy was analyzed histologically and spectophotomerically for RNA, DNA and protein content. The digastric muscle underwent transient atrophy with initiation of distraction but regenerated completely after 48 days of fixation. The masseter muscle was unchanged initially but showed evidence of atrophy only after 20 mm of distraction it continued to exhibit evidence of atrophy during fixation. Protein synthesis was decreased significantly during periods of atrophy in the masseter; no such change was noted in the digastric. Unlike the masseter, the digastric fibers lie in a plane parallel to the vector of distraction. These findings suggest that any muscle affected by skeletal distraction in the same plane or vector (e.g., digastric) adapts with compensatory regeneration and hypertrophy. Moreover, those muscles lying in a different plane (e.g., masseter) show persistent evidence of atrophy with decreased protein synthesis
— id: 99041, year: 1997, vol: 99, page: 366, stat: Journal Article,

The syndecan family of proteoglycans. Novel receptors mediating internalization of atherogenic lipoproteins in vitro
Fuki IV; Kuhn KM; Lomazov IR; Rothman VL; Tuszynski GP; Iozzo RV; Swenson TL; Fisher EA; Williams KJ
1997 Sep 15;100(6):1611-1622, Journal of clinical investigation
Cell-surface heparan sulfate proteoglycans have been shown to participate in lipoprotein catabolism, but the roles of specific proteoglycan classes have not been examined previously. Here, we studied the involvement of the syndecan proteoglycan family. First, transfection of CHO cells with expression vectors for several syndecan core proteins produced parallel increases in the cell association and degradation of lipoproteins enriched in lipoprotein lipase, a heparan-binding protein. Second, a chimeric construct, FcR-Synd1, that consists of the ectodomain of the IgG Fc receptor Ia linked to the highly conserved transmembrane and cytoplasmic domains of syndecan-1 directly mediated efficient internalization, in a process triggered by ligand clustering. Third, internalization of lipase-enriched lipoproteins via syndecan-1 and of clustered IgGs via the chimera showed identical kinetics (t1/2 = 1 h) and identical dose-response sensitivities to cytochalasin B, which disrupts microfilaments, and to genistein, which inhibits tyrosine kinases. In contrast, internalization of the receptor-associated protein, which proceeds via coated pits, showed a t1/2 < 15 min, limited sensitivity to cytochalasin B, and complete insensitivity to genistein. Thus, syndecan proteoglycans can directly mediate ligand catabolism through a pathway with characteristics distinct from coated pits, and might act as receptors for atherogenic lipoproteins and other ligands in vivo
— id: 37320, year: 1997, vol: 100, page: 1611, stat: Journal Article,

Fenestrated fontan procedure: evolution of technique and occurrence of paradoxical embolism
Quinones JA; Deleon SY; Bell TJ; Cetta F; Moffa SM; Freeman JE; Vitullo DA; Fisher EA
1997 May-Jun;18(3):218-221, Pediatric cardiology
The Fenestrated Fontan procedure (FFP) has improved outcome in high risk patients. The technique is evolving, however, and complications are not fully known. Over a 3-year period 13 patients (mean age 35 +/- 29 months) underwent an FFP in our institution. In the first two patients the fenestration had to be created because of high right atrial pressure and low cardiac output; in 11 patients the FFP was planned. In three patients the sutures for the adjustable fenestration were crossing the defect. In 10 patients, purse-string sutures were placed around but not across the defect. Because large fenestrations were created in 11 patients (8-12 mm) Glenn shunts were performed to improve arterial saturation. The postoperative course was relatively uneventful, with chest tubes being removed 1-8 days (mean 4 +/- 3 days) postoperatively and the hospital stay ranging from 7 to 27 days (mean 14 +/- 6 days). One patient had bleeding and another had a mediastinal abscess. The first patient died (7.6%) because of hemodynamic instability due to prolonged cardiopulmonary bypass from the creation and enlargement of the fenestration. One patient had a paradoxical cerebral embolism from clots that formed on the sutures crossing the fenestration. Because of this problem the remaining patients were placed on salicylates while awaiting closure of their fenestration. All 12 patients had their fenestrations closed, performed under local anesthesia in 9, at mediastinal abscess drainage in 1, and spontaneously in 2. We conclude that creation of large fenestrations in combination with Glenn shunts and the use of adjustable fenestrations are viable modifications of the FFP. The use of purse-string sutures around the fenestration and antiplatelet drugs can probably minimize the occurrence of paradoxical embolism
— id: 37325, year: 1997, vol: 18, page: 218, stat: Journal Article,

UVB irradiation alters cellular responses to cytokines: role in extracellular matrix gene expression
Werth VP; Williams KJ; Fisher EA; Bashir M; Rosenbloom J; Shi X
1997 Mar;108(3):290-294, Journal of investigative dermatology
Solar radiation causes cutaneous photodamage characterized by alterations in the quantity and structure of the extracellular matrix. We determined the direct and cytokine-mediated effects of UV irradiation on mRNA levels for two matrix elements, tropoelastin and fibrillin 1. (i) Comparison of normal versus end-stage photodamaged skin failed to reveal differences in these message levels. (ii) Acutely irradiated skin showed suppression of both tropoelastin and fibrillin mRNAs. (iii) UVB irradiation (50 mJ) of cultured skin fibroblasts suppressed fibrillin mRNA by 50%, consistent with a direct effect of radiation. Addition to the cultured fibroblasts of several cytokines upregulated by UVB showed that IL-1alpha had no effect on fibrillin mRNA in unirradiated cells, but in irradiated cells, this cytokine enhanced the suppression of fibrillin mRNA. There were no changes in the message stability, suggesting altered gene transcription. In contrast, UVB had no effect on tropoelastin mRNA levels in cultured fibroblasts, indicating the absence of a direct effect of radiation. IL-1alpha stimulated tropoelastin mRNA 2.8-fold in unirradiated cells, and this stimulation was entirely blocked by UVB. Overall, our results indicate acute suppression of matrix genes by UVB in vivo. The suppression of fibrillin message was a direct effect of UVB on fibroblasts and was augmented by IL-1alpha. Suppression of tropoelastin message by UVB occurred in vitro only in IL-1alpha-stimulated cells. We conclude that UVB substantially alters the pattern of cellular response to cytokines. The interplay between UVB and cytokines is essential to explain the acute responses of matrix genes to UVB in vivo
— id: 37328, year: 1997, vol: 108, page: 290, stat: Journal Article,

Properties of pancreatic carboxyl ester lipase in mRNA-injected Xenopus oocytes and transfected mammalian hepatic and intestinal cells
Zolfaghari R; Shamir R; Fisher EA
1997 ;286(43):80-101, Methods in enzymology
— id: 37319, year: 1997, vol: 286, page: 80, stat: Journal Article,

Early pulmonary homograft failure from dilatation due to distal pulmonary artery stenosis
DeLeon SY; Tuchek JM; Bell TJ; Hofstra J; Vitullo DA; Quinones JA; Fisher EA
1996 Jan;61(1):234-236, Annals of thoracic surgery
Early progressive pulmonary homograft insufficiency developed in an 11-month-old infant after repair of truncus arteriosus because of dilatation secondary to the presence of residual distal pulmonary artery stenosis and hypoplasia. Before repair, the pulmonary artery branches were discontinuous, with the right pulmonary artery being somewhat hypoplastic and originating from the trunk, and the left pulmonary artery supplied by a modified Blalock-Taussig shunt created in the newborn period. At repair, a pulmonary homograft was used to connect the branches. Progressive cardiomegaly and oxygen dependance occurred 3 weeks postoperatively. Cardiac catheterization showed systemic right ventricular pressure, severe homograft insufficiency, and residual distal pulmonary artery stenosis and hypoplasia. On reoperation at 3 months postoperatively, the homograft annulus diameter increased from 14 mm to 16 mm. Dilatation and insufficiency probably occurred because the right ventricle and homograft distal to the obstruction functioned as a unit during systole. The problem might have been minimized with the use of aortic homograft, which is thicker, or annular reinforcement with a synthetic material
— id: 37332, year: 1996, vol: 61, page: 234, stat: Journal Article,

Effect of experimental nephrosis on hepatic lipoprotein secretion and urinary lipoprotein excretion in rats expressing the human apolipoprotein A-I gene
Marsh JB; Diffenderfer MR; Fisher EA; Sowden M; Dong M; Paterniti JR; Burkey BF
1996 May;37(5):1113-1124, Journal of lipid research
When human apolipoprotein A-I was expressed in transgenic rats, induction of the nephrotic syndrome resulted in plasma A-I levels exceeding 10 mg/ml. Plasma lipids were no higher than in non-transgenic nephrotic rats. To explain this, the livers from four groups of rats were perfused: wild-type controls (WC), high expressor human apoA-I transgenic controls (TrGC), wild-type nephrotics (WN), and high expressor transgenic nephrotics (TrGN). Compared to the WC group, TrGC rats secreted the same amount of d < 1.063 g/ml lipoproteins but 50% more high density lipoprotein (HDL), with a 5-fold increase in total apoA-I output due to human apoA-I. Compared to the WC group, nephrosis in the WN rats caused a 2-fold increase in both d < 1.063 g/ml lipoproteins and HDL secretion with a 4.6-fold increase in rat apoA-I output. Compared to the TrGC group, nephrosis in the TrGN rats did not increase d < 1.063 g/ml lipoprotein secretion, but caused a 50% increase in HDL secretion and a 6-fold increase in human apoA-I output. The hepatic levels of mRNA for apoB and for HMG-CoA reductase, as well as the degree of apoB mRNA editing, were unchanged. Examination of the perfusate HDL by electron microscopy revealed spherical particles averaging 30 nm in diameter in the WC and WN rats and 17 and 20 nm in the TrGC and TrGN rats. Urinary HDL particles from the TrGN rats did not contain rat apoA-I and averaged 8.2 nm versus 11 nm in the WN rats. We conclude that the size of the nascent HDL, and subsequently of the mature HDL, is determined by the primary structure of apoA-I. In the TrGN rats, the heterogeneous mature HDL has a population of smaller human HDL which is more readily lost in the urine, accounting for the failure of plasma HDL levels to rise above those in TrGC rats. The fact that plasma triglyceride levels in TrGN rats were also not increased may relate to the failure of hepatic apoB secretion to increase, which in turn may have been due to saturation of the protein synthetic capacity by human apoA-I production
— id: 37330, year: 1996, vol: 37, page: 1113, stat: Journal Article,

Pancreatic carboxyl ester lipase: a circulating enzyme that modifies normal and oxidized lipoproteins in vitro
Shamir R; Johnson WJ; Morlock-Fitzpatrick K; Zolfaghari R; Li L; Mas E; Lombardo D; Morel DW; Fisher EA
1996 Apr 1;97(7):1696-1704, Journal of clinical investigation
Pancreatic carboxyl ester lipase (CEL) hydrolyzes cholesteryl esters (CE), triglycerides (TG), and lysophospholipids, with CE and TG hydrolysis stimulated by cholate. Originally thought to be confined to the gastrointestinal system, CEL has been reported in the plasma of humans and other mammals, implying its potential in vivo to modify lipids associated with LDL, HDL (CE, TG), and oxidized LDL (lysophosphatidylcholine, lysoPC). We measured the concentration of CEL in human plasma as 1.2+/-0.5 ng/ml (in the range reported for lipoprotein lipase). Human LDL and HDL3 reconstituted with radiolabeled lipids were incubated with purified porcine CEL without or with cholate (10 or 100 microM, concentrations achievable in systemic or portal plasma, respectively). Using a saturating concentration of lipoprotein-associated CE (4 microM), with increasing cholate concentration there was an increase in the hydrolysis of LDL- and HDL3-CE; at 100 microM cholate, the present hydrolysis per hour was 32+/-2 and 1.6+/-0.1, respectively, indicating that CEL interaction varied with lipoprotein class. HDL3-TG hydrolysis was also observed, but was only approximately 5-10% of that for HDL3-CE at either 10 or 100 microM cholate. Oxidized LDL (OxLDL) is enriched with lysoPC, a proatherogenic compound. After a 4-h incubation with CEL, the lysoPC content of OxLDL was depleted 57%. Colocalization of CEL in the vicinity of OxLDL formation was supported by demonstrating in human aortic homogenate a cholate-stimulated cholesteryl ester hydrolytic activity inhibited by anti-human CEL IgG. We conclude that CEL has the capability to modify normal human LDL and HDL composition and structure and to reduce the atherogenicity of OxLDL by decreasing its lysoPC content
— id: 37331, year: 1996, vol: 97, page: 1696, stat: Journal Article,

Clinical improvement after revision in Fontan patients
Vitullo DA; DeLeon SY; Berry TE; Bonilla JJ; Chhangani SV; Cetta F; Quinones JA; Bell TJ; Fisher EA
1996 Jun;61(6):1797-1804, Annals of thoracic surgery
BACKGROUND. Arrhythmias, decreased exercise tolerance, or malabsorption will develop in a significant number of Fontan patients. Fontan revision consisting of creation of lateral atrial tunnel, reconnection of the Glenn shunt when present, or both appears to improve these patients. METHODS. Over a 34-month period, 9 patients underwent Fontan revision. The mean age was 11 +/- 5 years and the mean interval from Fontan operation to revision was 3 +/- 2 years. The reason for revision included marked impairment in exercise capacity, inability to go to school consistently, and chronic fatigue in 6 patients, 3 of whom also had serious atrial arrhythmias. Five of the 6 patients had a classic Glenn shunt. The mean right atrial pressure was greater than the pressure of the Glenn shunt (20 +/- 1.6 versus 17 +/- 0.8 mm Hg). Three of the 6 patients also showed a significant gradient between the right or left pulmonary artery wedge and ventricular end-diastolic pressure, indicating pulmonary vein obstruction from the bulging atrial septum or partitioning patch (13 +/- 3 versus 6.8 +/- 1 mm Hg). The remaining 3 patients had revision because of malabsorption (1), hepatomegaly and obstructed right pulmonary veins from bulging atrial septum (1), and tricuspid insufficiency (1). Fontan revision was accomplished with creation of a lateral atrial tunnel and Glenn reconnection in 6 patients, Glenn reconnection in 2, and creation of a lateral atrial tunnel in 1. Four patients had additional procedures. RESULTS. One patient died of Pseudomonas pneumonia. Early extubation, chest tube removal, and postoperative hospital discharge were accomplished in 8 patients (mean = 1.4 +/- 1, 2.8 +/- 1, and 8 +/- 3 days, respectively). One patient died 8 months postoperatively of brain damage after ventricular fibrillation from attempted cardioversion for atrial flutter. The remaining patients had marked improvement in exercise capacity with ability to consistently go to school, improvement in duration and tolerance to arrhythmias on less medication, and resolution of malabsorption up to 37 months postoperatively (mean, 20 +/- 12 months). CONCLUSIONS. We conclude that creation of lateral atrial tunnel with excision of a bulging atrial septum or atrial partitioning patch that causes pulmonary venous obstruction, reconnection of the Glenn shunt, which allows better distribution of flow based on the pulmonary vascular bed and resistance of each lung, or a combination of these procedures will improve Fontan patients
— id: 37329, year: 1996, vol: 61, page: 1797, stat: Journal Article,

Dietary fat elevates hepatic apoA-I production by increasing the fraction of apolipoprotein A-I mRNA in the translating pool
Azrolan N; Odaka H; Breslow JL; Fisher EA
1995 Aug 25;270(34):19833-19838, Journal of biological chemistry
Elevated plasma high density lipoprotein cholesterol (HDL-C) levels are associated with a decreased risk for coronary heart disease. Ironically, diets enriched in saturated fat and cholesterol (HF/HC diets), which tend to accelerate atherosclerotic processes by increasing LDL cholesterol levels, also raise HDL-C. We have recently reported, using a human apoA-I (hapoA-1) transgenic mouse model, that the elevation of HDL-C by a HF/HC diet is attributable, in part, to an increase in the hepatic production of hapoA-1. To further define the hepatocellular processes associated with this induction, we have prepared primary hepatocytes from hapoA-1 transgenic mice. Rates of hapoA-1 secretion were 40% greater from cells prepared from animals fed the HF/HC relative to a low fat-low cholesterol (LF/LC) control diet. The abundance of hapoA-1 mRNA in these cells was similar between hepatocytes prepared from the HF/HC and LF/LC diet fed animals, suggesting a post-transcriptional mechanism that does not involve mRNA stability. Inhibition of secretion using brefeldin A revealed an increase in cellular hapoA-1 accumulation. Thus, the HF/HC diet apparently affects hepatic hapoA-1 production via a mechanism that is manifest prior to the exit of newly synthesized hapoA-1 from the Golgi. Pulse-chase experiments revealed a 39% greater peak hapoA-1 synthesis, with no difference in the degradation of total labeled hapoA-1 protein, as a result of the HF/HC diet feeding. Finally, resolution of liver S10 extracts via sucrose density sedimentation and metrizamide density equilibrium gradient centrifugation analyses both revealed similar increases (31 and 24%, respectively) in the relative percentage of hapoA-1 mRNA associated with the translating polysomal fractions as a result of the HF/HC feeding. Together, these data suggest that the HF/HC diet affects hepatic hapoA-1 production via a specific modulation in the relative amount of hapoA-1 mRNA in the polysomal pool. These observations provide an opportunity to explore a new mechanism regulating apoA-1 production and might lead to the development of novel therapies to elevate plasma HDL-C levels
— id: 37336, year: 1995, vol: 270, page: 19833, stat: Journal Article,

Overexpression of human apolipoprotein A-I in transgenic rats and the hyperlipoproteinemia associated with experimental nephrosis
Burkey BF; France D; Wang H; Ma X; Brand B; Abuhani C; Diffenderfer MR; Marsh JB; Paterniti JR Jr; Fisher EA
1995 Jul;36(7):1463-1473, Journal of lipid research
Hyperlipoproteinemia contributes both to kidney disease progression and the development of atherosclerosis. Elevated high density lipoprotein cholesterol and apolipoprotein A-I (apoA-I) serum levels are independent factors protective against the atherosclerotic process. We examined the effects in a transgenic rat model of human apoA-I expression on the hyperlipoproteinemia and edema after puromycin aminonucleoside-induced nephrosis in three groups of animals: low line (TgR[hAI]low, human plasma apoA-I = 16.0 mg/dl); high line (TgR[hAI]high, 284 mg/dl); and non-transgenic litter mates (TgR[hAI]non). Nephrosis increased total plasma apoA-I levels 2-fold in TgR[hAI]non rats (75 vs. 162 mg/dl) and 4-fold in the TgR[hAI]low (97 vs. 458 mg/dl) and TgR[hAI]high rats (356 vs. 1,346 mg/dl). In both transgenic lines, this increase was due mainly to elevations of serum human apoA-I. The hepatic steady-state levels of rat apoA-I mRNA increased 5- to 7-fold in all three groups, while human apoA-I mRNA levels increased 21- and 65-fold in the low and high expressing groups, respectively, indicating a different degree of responsiveness of the rat and human genes. While nephrotic TgR[hAI]non and TgR[hAI]low rats showed severe hyperlipoproteinemia and edema, much lower levels of edema and of serum triglycerides, phospholipids, and cholesterol were seen in the TgR[hAI]high group. Urinary excretion of apoA-I, phospholipids, and cholesterol was significantly increased in the TgR[hAI]high group, indicating this as one possible mechanism for the relatively lower serum levels of these lipids. We conclude that the human apoA-I gene is responsive to nephrosis and that human apoA-I-transgenic rats with this syndrome provide an animal model for the study of human high density lipoprotein and apoA-I metabolism
— id: 37338, year: 1995, vol: 36, page: 1463, stat: Journal Article,

Alternatives in biventricular repair of double-outlet left ventricle
DeLeon SY; Ow EP; Chiemmongkoltip P; Vitullo DA; Quinones JA; Fisher EA; Bharati S; Ilbawi MN; Pifarre R
1995 Jul;60(1):213-216, Annals of thoracic surgery
Wide variation in morphology of double-outlet left ventricle allows numerous surgical alternatives that require sorting out to develop a more organized approach. There is a high association between tricuspid abnormalities and right ventricular hypoplasia with double-outlet left ventricle that calls for either Fontan-type procedure or biventricular repair. With pulmonic stenosis, biventricular repair has been accomplished using right-sided conduits. When pulmonic stenosis is mild or absent, repair techniques without conduits depend on the commitment of the ventricular septal defect (VSD). With subaortic VSD and mild pulmonic valvar stenosis, we successfully performed translocation of the main pulmonary artery and valve to the right ventricle on 2 patients (ages 32 and 8 months). Both patients are doing well 2 years and 1 year postoperatively. Others have successfully connected the right ventricle to the pulmonary artery with intraventricular baffle by enlarging a subaortic VSD or when the VSD is either subpulmonic or doubly committed. With subaortic VSD, although it has not been reported, biventricular repair can also be accomplished using a right ventricle-to-aorta baffle combined by either atrial or arterial switch. We believe that a simplified management plan can be formed in double outlet left ventricle based on the size of the right ventricle, presence of pulmonic stenosis, and commitment of the VSD. Whenever possible, translocation of the main pulmonary artery and valve or intraventricular repair should be accomplished in double-outlet right ventricle minimizing the use of right-sided conduits and reoperation
— id: 37337, year: 1995, vol: 60, page: 213, stat: Journal Article,

Use of the native aortic valve as the pulmonary valve in the Ross procedure
DeLeon SY; Quinones JA; Miles RH; Hofstra J; Bell TJ; Fisher EA; Pifarre R
1995 Apr;59(4):1007-1010, Annals of thoracic surgery
The placement of a foreign valve in the pulmonary position using the Ross procedure requires reoperation. To circumvent this problem, we devised a method of reimplanting the native aortic valve in the pulmonary position, and successfully performed this procedure in a 12-year-old diabetic boy operated on for the treatment of aortic insufficiency. Although diseased, the reimplanted aortic valve functioned well, with trivial stenosis and insufficiency. This modification offers patients with aortic valve disease a potentially curative operation
— id: 37340, year: 1995, vol: 59, page: 1007, stat: Journal Article,

Semilunar valve switch in aortic insufficiency
Deleon SY; Quinones JA; Vitullo DA; Hofstra J; Fisher EA; Gamponia R; Torres L; Lopez W; Zamora R
1995 ;9(11):631-635, European journal of cardio-thoracic surgery
The use of the Ross procedure in young patients is gaining wider acceptance. The need for a foreign pulmonary valve that will require replacement, however, is a serious drawback. To circumvent this problem, we reimplanted the native aortic valve in the pulmonary position in four patients (ages 12, 15, 15 and 17 years old) operated on utilizing the Ross procedure for aortic insufficiency. One patient had congenital and three isolated rheumatic aortic insufficiency. The root replacement technique with coronary artery reimplantation was used. All patients did well initially with marked reduction of left ventricular dilatation and good function of the reimplanted native aortic valve. One patient, however, died a month later from rupture of a false aneurysm that developed at the pulmonary autograft to ascending aorta anastomosis. We feel that the use of the native aortic valve in the pulmonary position makes the Ross procedure more attractive and potentially curative. The diseased aortic valve works well in the pulmonary position because of lower pulmonary artery pressure and resistance
— id: 37343, year: 1995, vol: 9, page: 631, stat: Journal Article,

The incidence of patent foramen ovale in 1,000 consecutive patients. A contrast transesophageal echocardiography study
Fisher DC; Fisher EA; Budd JH; Rosen SE; Goldman ME
1995 Jun;107(6):1504-1509, Chest
STUDY OBJECTIVE: Patent foramen ovale (PFO) is present in 10 to 35% of people and has been reported to be an important risk factor for cardioembolic cerebrovascular accidents (CVAs) and transient ischemic attacks (TIAs), especially in younger patients. While contrast transthoracic echocardiography has been used to detect PFO, contrast transesophageal echocardiography (TEE) has a greater sensitivity. Prior studies reported the incidence of PFO in patients presenting with a CVA or TIA. DESIGN: To determine the incidence of PFO in a more general population, we reviewed 1,000 consecutive TEEs performed with contrast and color Doppler for the presence of PFO and other cardioembolic risk factors, including atrial septal aneurysm (ASA), aortic plaque, atrial fibrillation (AFib), and atrial thrombi. While imaging with monoplane or biplane TEE, multiple injections of agitated saline solution were injected during cough or Valsalva maneuver to detect flow through a PFO. PATIENTS: There were 482 male and 518 female patients with mean age of 60 +/- 17 years (range 11 to 93 years). RESULTS: Patent foramen ovale was found in 9.2% of all patients and, though seen in all age groups divided by decade, the incidence in patients aged 40 to 49 years was greater than those aged 70 to 79 years (12.96% vs 6.15%, p = 0.03). Contrast TEE had a much higher detection rate than color Doppler alone. Importantly, there was no greater incidence of PFO in patients with CVA vs those without CVA, or in male vs female patients. Also, there was a very strong correlation between the presence of ASA and PFO (p < .001). CONCLUSION: Thus, PFO detected by TEE, frequently seen with ASA, is seen in all age groups and does not in itself present a risk factor for CVA. The association of PFO with peripheral thrombosis and CVA needs further study
— id: 22866, year: 1995, vol: 107, page: 1504, stat: Journal Article,

Acute pulmonary hypertension complicating the arterial switch procedure
Freeman J; DeLeon SY; Miles RH; Downey FX; Hofstra J; Quinones JA; Fisher EA; Pifarre R
1995 Nov-Dec;16(6):297-300, Pediatric cardiology
Two neonates undergoing arterial switch procedure developed life-threatening pulmonary hypertension intraoperatively. In one patient, bradycardia, hypotension, and electrocardiographic (ECG) evidence of myocardial ischemia suddenly occurred 20 minutes after uneventful weaning from cardiopulmonary bypass. Lifting a palpably hypertensive main pulmonary artery (MPA) resulted in reproducible hemodynamic improvement. Because the patient was already on full ventilatory support and a nitroglycerin infusion, the MPA was suspended onto the anterior chest wall. In the other patient, after removal of intraoperative drapes, severe generalized swelling and cyanosis were noted. The central venous pressure had risen to 25 mmHg, and the PO2 had dropped to 52 mmHg on 100% FIO2. The systolic arterial pressure and ECG remained normal. Immediate reexploration revealed a palpably hypertensive MPA. The coronary arteries implanted more laterally on the neoaorta were uncompromised. Amrinone loading and infusion produced immediate improvement. We believe that surgeons should be aware that pulmonary hypertension can cause coronary artery compression and right heart failure in neonates undergoing the arterial switch procedure. Lateral placement of the coronary artery and aggressive use of pulmonary vasodilators can minimize the problem
— id: 37334, year: 1995, vol: 16, page: 297, stat: Journal Article,

Early identification of patients with native valve infectious endocarditis at risk for major complications by initial clinical presentation and baseline echocardiography
Goldman ME; Fisher EA; Winters S; Reichstein R; Stavile K; Gorlin R; Fuster V
1995 Dec;52(3):257-264, International journal of cardiology
Early identification of a high risk patient subgroup with infective endocarditis which develops a major complication (emboli, congestive heart failure, surgery for valve replacement, or death) during hospitalization would reduce morbidity, mortality and cost. Thus, for 74 patients with native valve infective endocarditis with documented vegetation by transthoracic two-dimensional echocardiogram, we reviewed 67 variables: history (15), physical examination (9), hematology/miscellaneous (7), chest X-ray (2), electrocardiogram (4), transthoracic two-dimensional echocardiograms (15) and hospital course (15). There were 48 men and 26 women, ages 45 +/- 19 years: 35 intravenous drug abusers and 39 non-users. There were 32 mitral, 21 tricuspid, 20 aortic, and 1 pulmonic valve vegetations; mean vegetation size was 1.4 +/- 0.9 cm2. Over the course of their hospitalization, 14 patients died (19%), 27 developed congestive heart failure (36%), 27 had systemic emboli (36%), and 22 required surgery (30%). The incidence of complications (death, heart failure or embolic events) did not differ between the drug abusers and non-users. Initial complaint of dyspnea on admission predicted the subsequent development of heart failure (P < 0.001), and a pre-admission embolus predicted a second in-hospital embolus (P < 0.001). Left atrial size, ventricular systolic or diastolic dimension did not effect prognosis. Importantly, a vegetation > 1.8 cm2 was 100% specific but only 30% sensitive for predicting the development of a complication. Vegetation mobility, shape, and number of cusps involved were not predictive. However, aortic valve vegetations had significantly more complications than those on the mitral valve (P < 0.03). By discriminant function analysis, 87% of major complications were predicted with the patient profile of having aortic valve vegetation, dyspnea on admission, prolonged preadmission fever, and no history of drug abuse; 75% of patients who developed heart failure were predicted by their having aortic valve vegetation, dyspnea, hypotension (systolic < 90 mm Hg), and no history of drug abuse; and 77% of patients requiring surgery were predicted by their having larger vegetation size, rales, and leftward shift of white blood cells. Thus, in native valve bacterial endocarditis with transthoracic echocardiographic documented vegetations, non-drug abusers with aortic vegetations, preadmission prolonged fevers, dyspnea, emboli and larger sized vegetations are at high risk for developing a major complication during their hospitalization
— id: 37333, year: 1995, vol: 52, page: 257, stat: Journal Article,

Safety of patent ductus arteriosus closure in premature infants without tube thoracostomy
Miles RH; DeLeon SY; Muraskas J; Myers T; Quinones JA; Vitullo DA; Bell TJ; Fisher EA; Pifarre R
1995 Mar;59(3):668-670, Annals of thoracic surgery
During a 30-month period, 34 premature infants underwent surgical closure of a patent ductus arteriosus. The mean gestational age at birth was 25 +/- 0.3 weeks and the mean age at the time of operation was 3 +/- 0.3 weeks (mean weight, 829 +/- 54 g). Indomethacin therapy had failed in 32 patients, and 2 had contraindications to its use. The initial 8 patients had parascapular incision and ligation of the patent ductus arteriosus; the last 26 patients had a short transaxillary incision and clipping. The average duration of the operation from the time of incision to skin closure was 36 +/- 2 minutes (range, 15 to 65 minutes). One patient (3%) needed chest tube insertion intraoperatively because of visceral pleura disruption. Two patients (5.8%) had a 'small pneumothorax' (< 10% of the lung field) that resolved within 24 hours. There was no morbidity or mortality directly related to the operative procedure, although 3 patients (8.8%) ultimately died from problems related to their severe prematurity. We conclude that surgical closure of patent ductus arteriosus without chest tube drainage can be accomplished safely in premature infants. Postoperative nursing care is simplified and the cost is reduced because the need for the chest tube and drainage system is eliminated and the number of chest radiograms needed postoperatively is reduced
— id: 37341, year: 1995, vol: 59, page: 668, stat: Journal Article,

The effects of O- and N-linked glycosylation on the secretion and bile salt-stimulation of pancreatic carboxyl ester lipase activity
Morlock-Fitzpatrick KR; Fisher EA
1995 Feb;208(2):186-190, Proceedings of the Society for Experimental Biology & Medicine
Pancreatic carboxyl ester lipase is a glycoprotein that requires millimolar concentrations of trihydroxy bile salts, such as cholate, for maximal catalytic activity against cholesteryl esters and triglycerides. Binding of cholate, with subsequent activation, has been proposed to occur in the carboxy-terminal region of carboxyl ester lipase, which contains multiple sites for O-linked glycosylation (1). To investigate the role of O- and N-linked glycosylation in the secretion of carboxyl ester lipase by cells and its activation by cholate, rat carboxyl ester lipase cDNA was transfected into the mutant chinese hamster ovary cell line, IdID, and the ability of the cells to modify the expressed carboxyl ester lipase by N- and O-linked glycosylation was modulated by using various incubation conditions and metabolic inhibitors. The results showed that, similar to other lipases, maximal secretion of carboxyl ester lipase activity required N-linked glycosylation. In contrast, O-linked glycosylation did not affect the secretion of carboxyl ester lipase activity. In addition, the cholate stimulation of hydrolysis was also independent of O-linked glycosylation
— id: 37342, year: 1995, vol: 208, page: 186, stat: Journal Article,

Regression of hypertrophic cardiomyopathy after modified Konno procedure
Quinones JA; DeLeon SY; Vitullo DA; Hofstra J; Cziperle DJ; Shenoy KP; Bell TJ; Fisher EA
1995 Nov;60(5):1250-1254, Annals of thoracic surgery
BACKGROUND. Septal myotomy-myectomy has been known to decrease the incidence of sudden death and produce regression in hypertrophic obstructive cardiomyopathy. Use of beta-blockers or calcium-channel blockers generally does not cause regression of the disease. METHODS. Having successfully performed modified Konno procedures in 13 patients with effective relief of diffuse subaortic stenosis, we applied the procedure in 2 patients with hypertrophic obstructive cardiomyopathy. Both patients (18 and 12 years old, respectively) presented with syncope, angina at rest, and dyspnea despite being on calcium channel blocker therapy. The echocardiographic outflow gradients were 66 mm Hg and 88 mm Hg, respectively, with moderate mitral regurgitation. RESULTS. Both patients had uneventful postoperative course. At 2 years and 1.5 years postoperatively, both patients were free of angina and syncopal episodes. Echocardiography showed absence of outflow gradients and mitral regurgitation. In 1 patient the septal and posterior wall thickness decreased from 3.4 and 1.7 cm preoperatively to 2.6 and 0.9 cm, respectively, postoperatively. In the other patient, the thickness decreased from 2.4 and 0.9 cm preoperatively to 0.8 and 0.7 cm, respectively, postoperatively. Left atrial diameter decreased from 5.4 to 4.7 cm in 1 patient, 3.5 to 2.6 cm in the other. CONCLUSIONS. We believe that the modified Konno procedure could produce more effective relief of obstruction and, therefore, significant regression and further reduction in sudden death in hypertrophic obstructive cardiomyopathy. On the basis of our experience, albeit limited, we encourage its application
— id: 37335, year: 1995, vol: 60, page: 1250, stat: Journal Article,

Role of bile salt-dependent cholesteryl ester hydrolase in the uptake of micellar cholesterol by intestinal cells
Shamir R; Johnson WJ; Zolfaghari R; Lee HS; Fisher EA
1995 May 16;34(19):6351-6358, Biochemistry
The bile salt-dependent cholesteryl ester hydrolase (CEH; EC 3.1.1.13) has been proposed to promote the intestinal absorption of both the free and esterified (FC, CE) forms of dietary cholesterol. For example, it was recently reported that in the human intestinal cell line CaCo2, addition of bovine CEH to the medium increased the uptake and intracellular esterification of micellar FC supplied at subphysiological concentrations [Lopez-Candales et al. (1993) Biochemistry 32, 12085-12089]. To test the ability of CEH to promote micellar cholesterol uptake in a CaCo2 system under more physiological conditions, an in vitro model was developed. Cells stably expressing rat CEH were created by DNA transfection (Tr cells), and the uptake of micellar FC and its intracellular esterification were measured using isotopic methods in Tr and control cells. Experimental parameters that were varied included micellar composition (monoolein or egg PC; FC, CE, or both), the final concentration of micellar cholesterol (1 nM to 50 microM), the origin of CEH (endogenously synthesized vs exogenously added), and the species source of enzyme (rat, pig, man). The uptake of cholesterol that was derived from micellar CE was significantly increased 5-10-fold (p < 0.001) in Tr vs control cells as a result of the hydrolysis of the CE by the CEH and subsequent uptake of the liberated free cholesterol. In contrast, the uptake of micellar FC was not increased by the presence of CEH, whether it was endogenous or exogenous. In addition, based on TLC analysis of extracted cellular lipids, there was no evidence that CEH promoted the esterification of the FC that was taken up.(ABSTRACT TRUNCATED AT 250 WORDS)
— id: 37339, year: 1995, vol: 34, page: 6351, stat: Journal Article,

Chloride transport activation by plasma osmolarity during rapid adaptation to high salinity of Fundulus heteroclitus
Zadunaisky JA; Cardona S; Au L; Roberts DM; Fisher E; Lowenstein B; Cragoe EJ Jr; Spring KR
1995 Feb;143(3):207-217, Journal of membrane biology
Transition from low salt water to sea water of the euryhaline fish, Fundulus heteroclitus, involves a rapid signal that induces salt secretion by the gill chloride cells. An increase of 65 mOsm in plasma osmolarity was found during the transition. The isolated, chloride-cell-rich opercular epithelium of sea-water-adapted Fundulus exposed to 50 mOsm mannitol on the basolateral side showed a 100% increase in chloride secretion, which was inhibited by bumetanide 10(-4) M and 10(-4) M DPC (N-Phenylanthranilic acid). No effect of these drugs was found on apical side exposure. A Na+/H+ exchanger, demonstrated by NH4Cl exposure, was inhibited by amiloride and its analogues and stimulated by IBMX, phorbol esters, and epithelial growth factor (EGF). Inhibition of the Na+/H+ exchanger blocks the chloride secretion increase due to basolateral hypertonicity. A Cl-/HCO3- exchanger was also found in the chloride cells, inhibited by 10(-4) M DIDS but not involved in the hyperosmotic response. Ca2+ concentration in the medium was critical for the stimulation of Cl- secretion to occur. Chloride cell volume shrinks in response to hypertonicity of the basolateral side in sea-water-adapted operculi; no effect was found on the apical side. Fresh-water-adapted fish chloride cells show increased water permeability of the apical side. It is concluded that the rapid signal for adaptation to higher salinities is an increased tonicity of the plasma that induces chloride cell shrinkage, increased chloride secretion with activation of the Na+K+2Cl- cotransporter, the Na+/H+ exchanger and opening of Cl- channels
— id: 6784, year: 1995, vol: 143, page: 207, stat: Journal Article,

Alternative polyadenylation of apolipoprotein B RNA is a major cause of B-48 protein formation in rat hepatoma cell lines transfected with human apoB-100 minigenes
Heinemann T; Metzger S; Fisher EA; Breslow JL; Huang LS
1994 Dec;35(12):2200-2211, Journal of lipid research
The human apoB gene encodes an mRNA of 14121 nucleotides. In liver the apoB gene products a full-length mature protein of 4,536 amino acids (B-100), whereas in the intestine this gene produces a truncated protein of 2,152 amino acids (B-48). B-48 results from RNA editing of nucleotide 6666 from C to U, thereby producing a stop codon at position 2153. Rat liver has been shown to contain apoB RNA editing capability resulting in production of both B-100 and B-48. To create an in vitro expression system for human B-100, a minigene with a wild type coding sequence for the entire B-100 protein (B-100/Gln) was stably transfected into rat hepatoma cells (McA-RH7777). Similarly, a minigene with mutation at nucleotide 6667 that allowed translation even after editing of nucleotide 6666 (B-100/Leu, nonstop mutant), a minigene with an additional nonsense mutation at nucleotide 7053 to produce B-50 (B-50/Leu), and a truncated wild type minigene with a stop signal at codon 3261 to produce B-74 and an mRNA of 10 kb (B-74/Gln) were also transfected. Very little full-length B-100 and B-74 was produced by any of the respective constructions, including the B-100/Leu with the nonstop mutation. Transfection with B-100/Gln, B-100/Leu and B-74/Gln constructions produced greater than 90% of apoB as B-48, whereas the B-50/Leu construction produced 76% B-50 and 24% B-48. The inability of the B-100/Leu construction to produce B-100 suggested an explanation for B-48 production other than RNA editing. Northern blot analysis showed that the RNA produced by all four transfectants was shortened to a size of about 7 kb. A 10-kb but no 7-kb RNA was observed in the B-74/Leu construction when transfected to Chinese hamster ovary cells suggesting cell type specificity in generation of a shortened RNA. The 3' end of apoB RNA from McA-RH7777 B-100/Leu transfectants was reverse transcribed, cloned, and sequenced. This revealed two species of RNA: one polyadenylated at or near nucleotide 6775 capable of coding for B-48, the other polyadenylated at nucleotide 7080 capable of coding for B-50. In 18% of the cDNA clones, nucleotide 6666 was edited from C to T. In 6 of 34 clones, addition of the poly(A) tail after nucleotide 6774 created a TAA stop codon, whereas no stop signals could be detected in the remaining clones.(ABSTRACT TRUNCATED AT 400 WORDS)
— id: 37344, year: 1994, vol: 35, page: 2200, stat: Journal Article,

The effects of n-3 fatty acids on the secretion of carboxyl-terminally truncated forms of human apoprotein B
Wang H; Yao Z; Fisher EA
1994 Jul 15;269(28):18514-18520, Journal of biological chemistry
We have previously reported that in primary rat hepatocytes, n-3 fatty acid (either eicosapentaenoic or docosahexaenoic) stimulates intracellular degradation of apoprotein B100 (apoB100) and apoB48 (Wang, H., Chen, X., and Fisher, E.A. (1993) J. Clin. Invest. 91, 1380-1389). There was a greater effect on apoB100 than on apoB48. Rat hepatoma (McArdle RH-7777) cell lines expressing carboxyl-truncated human apoB species apoB42, apoB28, and apoB18 were used to explore the relationship between the effects of n-3 fatty acids and apoB lipidation. After density gradient separation of conditioned media, apoB42 was found at d < 1.21 (lipid-rich), apoB18 at d > 1.21 (lipid-poor), and apoB28 in both fractions. After incubation with albumin complexed with eicosapentaenoic or docosahexaenoic acids, relative to oleic acid, the secretion of newly synthesized apoB was 35% (apoB42), 54% (apoB28), and 96% (apoB18). Further analysis of the apoB28 data showed decreased secretion of only lipid-rich (d < 1.21) apoB28. Pulse-chase studies indicated that with n-3 fatty acid there was increased intracellular degradation of apoB42 concomitant with its decreased secretion. We conclude that the ability of the n-3 fatty acids to promote apoB degradation correlated with the degree of lipidation of the secreted apoB, consistent with specialized intracellular pathways for the degradation of apoB and the assembly of buoyant, apoB-containing lipoproteins
— id: 37346, year: 1994, vol: 269, page: 18514, stat: Journal Article,

Guidelines for exercise testing in the pediatric age group. From the Committee on Atherosclerosis and Hypertension in Children, Council on Cardiovascular Disease in the Young, the American Heart Association
Washington RL; Bricker JT; Alpert BS; Daniels SR; Deckelbaum RJ; Fisher EA; Gidding SS; Isabel-Jones J; Kavey RE; Marx GR; et al.
1994 Oct;90(4):2166-2179, Circulation
Exercise testing of children differs from adult exercise testing in many ways beyond the technical issues related to test performance that are addressed in this report. Disease processes that produce myocardial ischemia are relatively rare in children compared with adults. Exercise testing may be useful in these cases, but the use of testing to assess functional capacity or cardiac rhythms will be encountered more often. Although the precise role of exercise testing in patient evaluation or long-term management of the cardiac patient will vary somewhat from center to center, exercise testing is often essential to diagnose and to direct treatment in a wide variety of clinical problems. An understanding of the role of exercise testing for children with known or suspected heart abnormalities is an essential part of the training of pediatric cardiologists. The staff of the pediatric exercise laboratory should be available to discuss with the clinician when a test might be of value in a specific case in addition to providing advice about the specifics of the performance of the test and offering age- and size-appropriate normal data from the laboratory with test interpretation
— id: 37345, year: 1994, vol: 90, page: 2166, stat: Journal Article,

Hepatic polysomes that contain apoprotein B mRNA have unusual physical properties
Chen X; Sparks JD; Yao Z; Fisher EA
1993 Oct 5;268(28):21007-21013, Journal of biological chemistry
To characterize the association of the mRNA for apoprotein B (apoB) with ribosomes, rat hepatic cytoplasmic extracts were fractionated by density gradient centrifugation. On linear sucrose gradients, the sedimentation velocity of the 14.4-kilobase apoB mRNA was retarded compared to the mRNAs for other hepatic proteins, which were concentrated in fractions containing the bulk of the polysomes. This unusual distribution of apoB mRNA could not be explained by cotranslational association of nascent apoB peptides with lipids, based on experiments using either detergents to delipidate proteins or puromycin to release nascent peptides from polysomes. The results were also not the result of the editing of apoB mRNA, since the sucrose gradient distributions of both edited and nonedited forms were similar. In contrast, the distribution of a 3'-truncated apoB mRNA (apoB-42, 5.8 kilobases) expressed in rat hepatoma cells resembled that of mRNA of a typical hepatic protein. As opposed to the sedimentation velocity results, on equilibrium density gradients most hepatic apoB mRNA was found in the fraction that contained polysomes. Based on these data, the elongation rate of nascent apoB, and the calculated translational yield of apoB mRNA, we conclude that the majority of rat hepatic apoB mRNA must be part of polysomal complexes with unusual physical properties related to the presence of sequence(s) in the 3'-region of the message. These sequences may either be primary determinants of structural features or binding sites for protein factors that effect conformational changes
— id: 37348, year: 1993, vol: 268, page: 21007, stat: Journal Article,

Obligatory Glenn shunt in fenestrated Fontan
DeLeon SY; Freeman JE; Ow EP; Quinones JA; Bell TJ; Fisher EA; Downey FX; Sullivan HJ; Pifarre R
1993 Sep;56(3):510-514, Annals of thoracic surgery
Five high-risk patients undergoing the Fontan operation required large fenestration (1 cm) because of high central venous pressure and low cardiac output. Because of major arterial desaturation, obligatory Glenn shunts were performed. Three patients had pulmonary atresia, 1 had tricuspid atresia 1-B, and the fifth had single ventricle with subaortic stenosis. The age ranged from 16 to 40 months (mean age, 25 +/- 9 months) and weight from 7.9 to 14.6 kg (mean weight, 11 +/- 2 kg). One patient had single and 3 had bilateral subclavian pulmonary artery shunts. The fifth patient had pulmonary artery banding and coarctation repair followed by an aortopulmonary window and central shunt. The first 2 patients repeatedly had to go back on cardiopulmonary bypass for a larger fenestration and subsequently had an obligatory Glenn shunt because of arterial desaturation. The last 3 patients had planned obligatory Glenn shunt and large fenestration. The first patient died on the second postoperative day of a combination of prolonged operation, repeated cardiopulmonary bypass, and periods of hemodynamic instability. Three patients had closure of the adjustable fenestration under local anesthesia at 4, 5, and 8 weeks postoperatively. The last patient is awaiting closure. We believe that in certain high-risk patients, a large fenestration combined with an obligatory Glenn shunt should be considered to minimize repeated cardiopulmonary bypass and urgent tightening or closure of fenestration in the immediate postoperative period
— id: 37349, year: 1993, vol: 56, page: 510, stat: Journal Article,

Right ventricle-to-aorta conduit in pulmonary atresia with intact ventricular septum and coronary sinusoids
Freeman JE; DeLeon SY; Lai S; Fisher EA; Ow EP; Pifarre R
1993 Dec;56(6):1393-1395, Annals of thoracic surgery
A 20-month-old girl with pulmonary atresia, intact ventricular septum, and ventriculocoronary connections underwent successful interposition of a right ventricle-to-aorta conduit and Fontan operation. The patient initially had a modified Blalock-Taussig shunt at birth and subsequently a bidirectional Glenn shunt at 8 months of age. After Fontan and right ventricle-to-aorta conduit placement, the suprasystemic right ventricular pressure dropped to systemic levels without causing myocardial injury. Additionally, the right ventricular cavity enlarged. We believe that the use of a right ventricle-to-aorta conduit should provide a valuable alternative and improve the outlook of certain patients with pulmonary atresia, intact ventricular septum, and ventriculocoronary connections
— id: 37347, year: 1993, vol: 56, page: 1393, stat: Journal Article,

A predictor for side effects in patients with Alzheimer's disease treated with deferoxamine mesylate
Kruck TP; Fisher EA; McLachlan DR
1993 Jan;53(1):30-37, Clinical pharmacology & therapeutics
In a previously reported clinical trial, patients with Alzheimer's disease were treated with deferoxamine mesylate, which resulted in a 50% reduction in the average rate of deterioration over 2 years. There were five deaths in the untreated group during the trial and no deaths in the treated group, although five of 25 treated patients reported anorexia. Deferoxamine metabolite analysis of urine for 24 hours after deferoxamine injection from sensitive and nonsensitive patients showed marked differences. Occurrence of side effects correlated with increased formation of a monoamine oxidase catalyzed (major) metabolite, MFO1. The metabolite ratio, MFO1/total metabolites, plus parent drug (TOT) showed a bimodal distribution with a mean +/- SD value of 0.68 +/- 0.06 for the nonsensitive and 0.79 +/- 0.04 for sensitive patients. The MFO1/TOT ratio discriminates between sensitive and nonsensitive patients, and we suggest that the half difference mark between the two mean values (0.735) can be used as a predictor of side effects. Patients with a MFO1/TOT ratio of greater than 0.70 would be considered at risk and observed for onset of side effects. Patients with a MFO1/TOT ratio greater than 0.80 would be considered for immediate adjunct treatment with isoniazid or other monoamine oxidase inhibitors
— id: 37354, year: 1993, vol: 53, page: 30, stat: Journal Article,

Rabbit and rat liver nuclei both contain proteins which bind to the regions controlling apolipoprotein A-I gene expression
Reisher SR; Fisher EA; Feinstein SI
1993 Aug 15;216(1):247-253, European journal of biochemistry
We have tested the 5' flanking region of the apolipoprotein A-I (apo A-I) gene, which controls its expression in hepatic cells, for the ability to bind protein factors from rat and rabbit liver nuclei. We found that nuclear extracts from each species contain proteins which bind to three sites in the region which have been shown to be important for control of apo A-I gene transcription. These results contrast with a previous report [Dai, P. H., Lan, S. S. F., Ding, X. H. & Chao, Y. S. (1990) Eur. J. Biochem. 190, 305-310] that no rabbit liver nuclear protein could be detected which binds to the rat apo A-I upstream region and that this lack of binding could explain the failure of the rabbit liver to express the apo A-I gene. We have also shown that the low levels of apo A-I mRNA in the rabbit liver correlate with decreased transcription. Our data suggest that the lack of apo A-I gene expression in liver is a result of transcriptional control but cannot be due to simple lack of protein binding to this region of DNA
— id: 37350, year: 1993, vol: 216, page: 247, stat: Journal Article,

N-3 fatty acids stimulate intracellular degradation of apoprotein B in rat hepatocytes
Wang H; Chen X; Fisher EA
1993 Apr;91(4):1380-1389, Journal of clinical investigation
When rat hepatocytes were incubated with albumin complexed to the n-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), rather than to oleic acid (OA), the secretion of newly synthesized apoprotein B100 (apoB100) or B48 (apoB48) was reduced, despite stimulation of cellular triglyceride synthesis by all three fatty acids. When pulse-chase studies of apoB synthesis and secretion were performed in the presence of OA, EPA, or DHA, there were no significant changes in the initial synthetic rates of either apoB species. However, during the chase period, the total recovery of labeled apoB100 and apoB48 from the cell and medium was less in the n-3 fatty acid groups, so that by 150 min, approximately half as much labeled apoB was recovered as in the OA group. Overall, the decreased accumulation in medium of labeled apoB in the presence of EPA and DHA could be quantitatively accounted for by increased degradation of intracellular apoB. Thus, in the primary hepatocyte, apoB degradation is not constitutive, but can be regulated by n-3 fatty acids
— id: 37353, year: 1993, vol: 91, page: 1380, stat: Journal Article,

Simple method for extracting RNA from cultured cells and tissue with guanidine salts
Zolfaghari R; Chen X; Fisher EA
1993 Jul;39(7):1408-1411, Clinical chemistry
We have developed a simple protocol for isolating RNA from both cell culture and tissue from human and animal sources, using guanidine thiocyanate and guanidine hydrochloride, but no organic solvents. The protocol reproducibly yielded 15 to 25 micrograms of high-quality RNA per 10(6) cells of human and animal origin and 1 to 1.1 mg of RNA per gram of human placental tissue. The RNA so obtained was ribonuclease-free and not contaminated by DNA. It was suitable for reverse transcription-polymerase chain reaction, Northern blot analysis, and in vitro expression of proteins. Thus, the molecular assessment of both research and clinical samples can be readily and reliably initiated by the application of this protocol
— id: 37351, year: 1993, vol: 39, page: 1408, stat: Journal Article,

The effects of varying the expression of a neutral cholesteryl ester hydrolase on the turnover of cholesteryl ester in rat hepatoma cells
Zolfaghari R; Glick JM; Fisher EA
1993 Jun 25;268(18):13532-13538, Journal of biological chemistry
A neutral bile salt-dependent cholesteryl ester hydrolase (CEH) in rat liver has been shown to be indistinguishable from the pancreatic CEH by a number of criteria (Harrison, E. H. (1988) Biochim. Biophys. Acta 963, 28-34; Zolfaghari, R., Harrison, E. H., Ross, A. C., and Fisher, E. A. (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 6913-6919; Camulli, E. D., Linke, M. J., Brockman, H. L., and Hui, D. Y. (1989) Biochim. Biophys. Acta 1005, 177-182). The rat hepatoma cell line Fu5AH, which lacks this particular CEH activity, was stably transfected with the cDNA of rat pancreatic CEH, and the effects on cholesterol and cholesteryl ester metabolism in clones with varying levels of CEH expression determined. In spite of significant amounts of intracellular enzyme protein demonstrated by Western blotting, in cell lysates there was a consistently low level of catalytic activity, and in cultured cells there was no evidence that CEH served as an effective intracellular cholesteryl ester hydrolase or synthase. In contrast, the catalytic activity of the secreted enzyme was relatively higher and there was a small, but significant, increase in the ability of high density lipoprotein (added to the medium) to promote the clearance of cholesteryl ester from cells secreting high levels of CEH. Overall, these results suggest that in the liver, intracellular CEH does not significantly affect the turnover of cholesteryl esters and warrant future studies focusing on the function of the secreted enzyme. For example, secreted CEH may modify lipoproteins and affect their interactions with cells
— id: 37352, year: 1993, vol: 268, page: 13532, stat: Journal Article,

Mechanism of hypertriglyceridemia in human apolipoprotein (apo) CIII transgenic mice. Diminished very low density lipoprotein fractional catabolic rate associated with increased apo CIII and reduced apo E on the particles
Aalto-Setala K; Fisher EA; Chen X; Chajek-Shaul T; Hayek T; Zechner R; Walsh A; Ramakrishnan R; Ginsberg HN; Breslow JL
1992 Nov;90(5):1889-1900, Journal of clinical investigation
Hypertriglyceridemia is common in the general population, but its mechanism is largely unknown. In previous work human apo CIII transgenic (HuCIIITg) mice were found to have elevated triglyceride levels. In this report, the mechanism for the hypertriglyceridemia was studied. Two different HuCIIITg mouse lines were used: a low expressor line with serum triglycerides of approximately 280 mg/dl, and a high expressor line with serum triglycerides of approximately 1,000 mg/dl. Elevated triglycerides were mainly in VLDL. VLDL particles were 1.5 times more triglyceride-rich in high expressor mice than in controls. The total amount of apo CIII (human and mouse) per VLDL particle was 2 and 2.5 times the normal amount in low and high expressors, respectively. Mouse apo E was decreased by 35 and 77% in low and high expressor mice, respectively. Under electron microscopy, VLDL particles from low and high expressor mice were found to have a larger mean diameter, 55.2 +/- 16.6 and 58.2 +/- 17.8 nm, respectively, compared with 51.0 +/- 13.4 nm from control mice. In in vivo studies, radiolabeled VLDL fractional catabolic rate (FCR) was reduced in low and high expressor mice to 2.58 and 0.77 pools/h, respectively, compared with 7.67 pools/h in controls, with no significant differences in the VLDL production rates. In an attempt to explain the reduced VLDL FCR in transgenic mice, tissue lipoprotein lipase (LPL) activity was determined in control and high expressor mice and no differences were observed. Also, VLDLs obtained from control and high expressor mice were found to be equally good substrates for purified LPL. Thus excess apo CIII in HuCIIITg mice does not cause reduced VLDL FCR by suppressing the amount of extractable LPL in tissues or making HuCIIITg VLDL a bad substrate for LPL. Tissue uptake of VLDL was studied in hepatoma cell cultures, and VLDL from transgenic mice was found to be taken up much more slowly than control VLDL (P < 0.0001), indicating that HuCIIITg VLDL is not well recognized by lipoprotein receptors. Additional in vivo studies with Triton-treated mice showed increased VLDL triglyceride, but not apo B, production in the HuCIIITg mice compared with controls. Tissue culture studies with primary hepatocytes showed a modest increase in triglyceride, but not apo B or total protein, secretion in high expressor mice compared with controls. In summary, hypertriglyceridemia in HuCIIITg mice appears to result primarily from decreased tissue uptake of triglyceride-rich particles from the circulation, which is most likely due to increased apo CIII and decreased apo E on VLDL particles. the HuCIIITg mouse appears to be a suitable animal model of primary familial hypertriglyceridemia, and these studies suggest a possible mechanism for this common lipoprotein disorder
— id: 37356, year: 1992, vol: 90, page: 1889, stat: Journal Article,

Fabry disease: an unusual cause of severe coronary disease in a young man
Fisher EA; Desnick RJ; Gordon RE; Eng CM; Griepp R; Goldman ME
1992 Aug 1;117(3):221-223, Annals of internal medicine
— id: 37357, year: 1992, vol: 117, page: 221, stat: Journal Article,

An in vitro model for essential fatty acid deficiency: HepG2 cells permanently maintained in lipid-free medium
Furth EE; Sprecher H; Fisher EA; Fleishman HD; Laposata M
1992 Nov;33(11):1719-1726, Journal of lipid research
A stable essential fatty acid-deficient cell type, known as HepG2-EFD, was derived from the lipoprotein-producing human hepatoma cell line HepG2. These cells are particularly useful for quantitative studies involving essential fatty acids (n-6 and n-3 fatty acids) in secreted lipoproteins. Radiolabeled essential fatty acids can be delivered to these cells without altering the specific activity of the fatty acids, since the deficient cells contain no endogenous essential fatty acids. Using these cells, radioactivity data (dpm) from metabolic studies can be converted directly to mass, and masses as low as a few pmoles can be accurately measured. HepG2-EFD cell cultures were established by growing HepG2 cells in medium containing delipidated serum. After 10 days of growth in delipidated medium, HepG2 cells were completely depleted of all essential fatty acids. Compensatory increases in nonessential fatty acids (n-9 and n-7 fatty acids) including 20:3n-9 (the Mead acid), which is the hallmark fatty acid of essential fatty acid deficiency, were also observed in HepG2-EFD cells. Despite the lack of exogenous fatty acids in the medium and the lack of essential fatty acids in the cells, export of very low density lipoprotein (VLDL)-associated apolipoprotein B by HepG2-EFD was the same as observed for parent HepG2 cells. However, the activity of beta-oxidation of fatty acids in HepG2-EFD cells was much lower than in the parent cell line.(ABSTRACT TRUNCATED AT 250 WORDS)
— id: 37355, year: 1992, vol: 33, page: 1719, stat: Journal Article,

Impaired hepatic apolipoprotein B and E translation in streptozotocin diabetic rats
Sparks JD; Zolfaghari R; Sparks CE; Smith HC; Fisher EA
1992 May;89(5):1418-1430, Journal of clinical investigation
Studies of streptozotocin-induced diabetes in rats have demonstrated that hepatic apo B and apo E production are reduced. To determine if reductions are related to decreases in hepatic mRNAs, we performed blotting analysis of total liver RNA with rat apo B, apo E, and albumin cDNA probes. The expected reduction in albumin mRNA levels to 48% of control livers occurred in diabetic rat liver, while apo B and apo E mRNA levels were unchanged. The proportion of translational stop codon (BSTOP) mRNA averaged 43% of total in diabetic rats similar to control levels. Long-term labeling experiments using [35S]methionine in primary cultures of rat hepatocytes and specific immunoprecipitations demonstrated production of apo B and apo E, and albumin by hepatocytes from diabetic rats was reduced to 37%, 53%, and 23% of controls. Pulse-chase studies, together with mRNA analyses, suggest that reduced hepatic secretion of apo B and apo E in diabetics is primarily a result of impaired translation and not intracellular degradation. Ribosome transit studies directly confirmed the prolonged elongation rates for apo B and apo E mRNAs in hepatocytes derived from diabetic rats. This effect was more pronounced on apo BH (higher molecular weight) than on apo BL (lower molecular weight). Treatment of diabetic rats with insulin for 7 d led to normalization of hepatic albumin mRNA levels with no substantial change in apo E mRNA levels. In contrast, insulin treatment resulted in significant increases in hepatic apo B mRNA over control levels. Results suggest hepatic albumin and apo B mRNA levels are responsive to insulin in the diabetic state
— id: 37358, year: 1992, vol: 89, page: 1418, stat: Journal Article,

Tissue and species differences in bile salt-dependent neutral cholesteryl ester hydrolase activity and gene expression
Zolfaghari R; Harrison EH; Han JH; Rutter WJ; Fisher EA
1992 Mar;12(3):295-301, Arteriosclerosis & thrombosis
Enzymatic activity and mRNA abundance for neutral bile salt-dependent cholesteryl ester hydrolase (CEH) were determined in rat and rabbit tissues. In rat liver and intestine, enzyme activity and mRNA levels varied independently. Particularly striking in most tissue samples was the absence of detectable CEH mRNA in the presence of enzymatic activity, suggesting that there was an exogenous source of enzyme. Rabbits differed from rats in four ways. First, neither CEH activity nor mRNA was present in any liver sample. Second, CEH mRNA was present in nearly all intestinal samples, and its abundance tended to correlate with enzymatic activity. Third, rabbit CEH mRNA was approximately 250 bases shorter than the rat message. Fourth, we have previously shown that rat plasma contains CEH activity, whereas in the present studies, rabbit plasma did not contain such activity. Overall, our studies indicate that CEH activity in rat liver, intestine, and plasma can be derived exogenously, most likely from the uptake and transport of pancreatic enzyme. In contrast, in rabbit the lack of CEH activity in plasma and liver and the capacity of the intestine for in situ synthesis of CEH suggest that this animal does not have the same ability to distribute pancreatic CEH. These species differences in CEH metabolism may partly explain the greater susceptibility of rabbit tissues to accumulate cholesteryl esters
— id: 37359, year: 1992, vol: 12, page: 295, stat: Journal Article,

Macrophages from nephrotic rats regulate apolipoprotein E biosynthesis and cholesterol content independently
Bass J; Fisher EA; Prack MM; Williams DL; Marsh JB
1991 Feb;87(2):470-475, Journal of clinical investigation
The effects of the nephrotic syndrome in rats on the cholesterol content and the biosynthesis of apolipoprotein E (apoE) by resident peritoneal macrophages have been investigated. Since the nephrotic syndrome has been associated with an increased risk of coronary atherosclerosis, we hypothesized that macrophages from nephrotic rats would accumulate cholesterol and undergo transformation into foam cells, with a concomitant increase in apoE biosynthesis. The nephrotic syndrome was induced in rats with puromycin aminonucleoside. Peritoneal macrophages exposed in vivo for 7-21 d to ascites fluid derived from plasma containing sixfold elevations of lipoproteins did not accumulate unesterified or esterified cholesterol. Nevertheless, immunoprecipitation assays after incubation of the isolated cells with [35S]methionine, or immunoblot analysis of the incubation medium demonstrated a 2.6-fold increase in apoE secretion compared with normal macrophages. This increase was accompanied by 5- to 10-fold increases in cellular apoE messenger RNA as determined by quantitative solution hybridization assay. Peritoneal macrophages cultured from nephrotic rats during the period of hypercholesterolemia also showed distinct and highly reproducible morphologic changes. The dissociation between apoE biosynthesis and macrophage cholesterol content provides new insight into the response of peritoneal macrophages in vivo to endogenous hyperlipemia
— id: 37362, year: 1991, vol: 87, page: 470, stat: Journal Article,

Adenosine in the emergency management of supraventricular tachycardia
Ros SP; Fisher EA; Bell TJ
1991 Aug;7(4):222-223, Pediatric emergency care
In summary, adenosine is highly effective in terminating paroxysmal supraventricular tachycardia, and its very short half-life and benign side effects make it a promising alternative to other modes of therapy presently used. Further controlled prospective studies are needed before adenosine can become the drug of choice in the management of paroxysmal supraventricular tachycardia in children
— id: 37361, year: 1991, vol: 7, page: 222, stat: Journal Article,

Transesophageal echocardiography: a new view of the heart
Fisher EA; Goldman ME
1990 Jul 15;113(2):91-93, Annals of internal medicine
— id: 37365, year: 1990, vol: 113, page: 91, stat: Journal Article,

Development of an intravenous desferrioxamine mesylate treatment protocol for swine: monitoring of desferrioxamine and metabolites by high-performance liquid chromatography
Fisher EA; McLachlan DR; Kruck TP; Mustard RA
1990 ;41(5):263-271, Pharmacology
Desferrioxamine (DFO) metabolism and its pharmacokinetics were studied in a swine model using high-performance liquid chromatography. DFO and three iron-binding metabolites occurred in plasma. Interindividual differences in pharmacokinetics and metabolism were observed. Urine analysis in 4 pigs showed three iron-binding metabolites. The mean percent dose excreted in urine in the form of the parent drug was 45 +/- 10% and 10 +/- 2% (means +/- SD) in the form of metabolites. Of the total amount of the parent drug infused, 3 h after initiation, 87% was in the form of DFO, whereas 13% was present as the DFO-iron III complex which represented 45 mg of urinary iron elimination. The described DFO infusion protocol provides for sufficient DFO to chelate significant amounts of ferric iron in excess of normal levels, thus allowing experimental studies of iron chelation in a variety of disease states
— id: 37366, year: 1990, vol: 41, page: 263, stat: Journal Article,

Suppression of deferoxamine mesylate treatment-induced side effects by coadministration of isoniazid in a patient with Alzheimer's disease subject to aluminum removal by ionspecific chelation
Kruck TP; Fisher EA; McLachlan DR
1990 Oct;48(4):439-446, Clinical pharmacology & therapeutics
Deferoxamine treatment may produce serious side effects that can be eliminated by modification of treatment and by control of deferoxamine metabolism. A patient suffering from dementia of the Alzheimer type with normal liver and kidney function who was treated with deferoxamine initially tolerated a dose of 7 mg/kg deferoxamine mesylate injected intramuscularly twice a day for a total of 5 days a week. After several months nausea and weight loss gradually developed in the patient that could be controlled initially by dose reduction, leading to levels inappropriate for aluminum chelation. HPLC analysis of blood and urine revealed several metabolites including, as a major component, a plasma monoamine oxidase (MAO) catalyzed end product MFO1. Coadministration of isoniazid, a plasma MAO inhibitor, with deferoxamine resulted in reduction of MFO1 from 81% to 8% accompanied by increases in the amounts of metabolite 2 (MFO2) from 2% to 24% and unmetabolized deferoxamine from 17% to 68% after 6 months of treatment. The side effects subsided, the patient regained weight, and treatment could be continued
— id: 37364, year: 1990, vol: 48, page: 439, stat: Journal Article,

The unstirred water layer as a site of control of apolipoprotein B secretion
Williams KJ; Brocia RW; Fisher EA
1990 Oct 5;265(28):16741-16744, Journal of biological chemistry
Apolipoprotein B-100 (apoB) is a constituent of low density lipoproteins that has been implicated in the development of coronary artery disease (Editorial (1988) Lancet 1, 1141-1142). It is produced primarily in the liver, but mechanisms of secretory control are unclear. We examined the possibility that rapid reuptake of newly secreted lipoproteins regulates the net output of apoB by cultured liver cells. Polyclonal blocking antibodies to the low density lipoprotein receptor markedly increased apoB output, and varying the width of the unstirred water layer around the cells also changed apoB output, consistent with local reuptake. Labeled apoB added to the bulk fluid phase of the incubation media was not detectably taken up, implying that re-uptake is predominantly local. We conclude that a major site of apoB secretory control resides in the unstirred water layer, external to the cell. Because many cells secrete products for which they possess receptors, local re-uptake from the unstirred water layer may be a general mechanism for secretory control
— id: 37363, year: 1990, vol: 265, page: 16741, stat: Journal Article,

Change in chromatin organization of the 3'-flanking region of the rat apoprotein E gene in neonatal rats after an increase in transcriptional activity
Fisher EA
1989 Mar;76(1):29-33, Atherosclerosis
To investigate if a change in chromatin organization is associated with the increased transcriptional activity of the apoprotein E (apo E) gene, a study was done in hepatic nuclei isolated after birth to identify areas in or flanking the rat apo E gene with increased sensitivity to DNase I. An area of preferential digestion in the 3'-flanking region of the apo E gene was identified in liver nuclei from 3-day-old pups but not in nuclei from fetal livers collected at day 20 of gestation. This hypersensitive area may contain information important for the regulated expression of the rat apo E gene
— id: 37369, year: 1989, vol: 76, page: 29, stat: Journal Article,

Gene polymorphisms and variability of human apolipoproteins
Fisher EA; Coates PM; Cortner JA
1989 ;9(2-3):139-160, Annual review of nutrition
— id: 37371, year: 1989, vol: 9, page: 139, stat: Journal Article,

Experimental atherosclerosis in rabbits fed cholesterol-free diets. 13. Interaction of proteins and fat
Kritchevsky D; Tepper SA; Davidson LM; Fisher EA; Klurfeld DM
1989 Feb;75(2-3):123-127, Atherosclerosis
The atherogenic and cholesterolemic effects of animal protein vis-a-vis plant protein are well documented. Virtually all the studies were carried out using diets high in saturated fat, such as coconut oil. In order to determine if the same effects were seen with less saturated fat, we have compared atherogenic effects of an animal protein (casein) with those of a plant protein (soybean protein isolate) fed with partially hydrogenated soybean oil (PHS) (iodine value 72) or soybean oil (iodine value 134) as part of a cholesterol-free semipurified diet. After 6 months only rabbits fed casein-PHS exhibited elevated levels of plasma and liver cholesterol and triglycerides and atherosclerosis. Rabbits fed soy protein-PHS had slightly higher plasma cholesterol and triglycerides than did those fed soy protein and soybean oil, but values in both groups were in the normal range. The different effects of animal and plant protein on lipidemia and atherosclerosis can be influenced by dietary fat and appear to be dependent on fat saturation
— id: 37370, year: 1989, vol: 75, page: 123, stat: Journal Article,

Effects of eicosapentaenoic and docosahexaenoic acids on apoprotein B mRNA and secretion of very low density lipoprotein in HepG2 cells
Wong SH; Fisher EA; Marsh JB
1989 Nov-Dec;9(6):836-841, Arteriosclerosis
Oleic acid (18:1n-9, OA), docosahexaenoic acid (22:6n-3, DHA), or eicosapentaenoic acid (20:5n-3, EPA) was added to HepG2 cells at a concentration of 1 mM in a 5:1 or 2:1 molar complex with bovine serum albumin (BSA), and this was incubated for 3 hours. The incorporation of 3H-glycerol into cellular and medium triglyceride (TG), and the mass of TG were measured. The effects of these fatty acids on the secretion of very low density lipoprotein (VLDL) apolipoprotein B (apo B) were estimated from the incorporation of 3H-leucine into the medium apo B in comparison to cells incubated with fatty acid-poor albumin. The secretion of human albumin by the cells was also estimated by immunochemical precipitation of the labeled albumin. In addition, the intracellular levels of apo B messenger ribonucleic acid (mRNA) were measured by the dot-blot hybridization technique. Relative to control cells incubated with BSA, OA (complexed to BSA at a 5:1 molar ratio) stimulated TG synthesis and secretion sevenfold. Compared to OA, EPA was 24% less effective for both processes, whereas DHA inhibited only the secretion of TG (-43%). The secretion of VLDL apo B was not affected by OA, but was decreased 31% by EPA and 54% by DHA. When the molar ratio of fatty acid complexed to albumin was changed to 2:1, similar results were obtained with respect to TG production. The levels of apo B mRNA relative to actin mRNA were not significantly altered by any of the fatty acids.(ABSTRACT TRUNCATED AT 250 WORDS)
— id: 37367, year: 1989, vol: 9, page: 836, stat: Journal Article,

Expression in Xenopus oocytes of rat liver mRNA coding for a bile salt-dependent cholesteryl ester hydrolase
Zolfaghari R; Harrison EH; Ross AC; Fisher EA
1989 Sep;86(18):6913-6916, Proceedings of the National Academy of Sciences of the United States of America
A catalytically active bile salt-dependent cholesteryl ester hydrolase (CEH) was expressed when Xenopus oocytes were injected with rat liver mRNA. The expressed CEH activity was highly dependent on the presence of trihydroxy bile salts (cholate or one of its conjugates); maximum hydrolytic activity was observed in the presence of 10 mM sodium cholate. The expressed CEH was not activated by dihydroxy bile salts (deoxycholate and its conjugates). In the presence of 10 mM sodium cholate, the CEH activity was maximal near pH 7 but was significant between pH 6 and 8. Monospecific immune IgG raised against rat pancreatic CEH completely inhibited the CEH expressed in Xenopus oocytes. Phenylmethylsulfonyl fluoride, a serine enzyme inhibitor, was inhibitory to the expressed CEH activity, whereas p-chloromercuribenzoate (up to 5 mM), a potent thiol-blocking agent, did not significantly inhibit the expressed activity. These experiments clearly demonstrate that the liver contains an mRNA encoding a bile salt-dependent CEH activity and suggest that the uptake of pancreatic enzyme is not necessarily the source of liver CEH as has been speculated
— id: 37368, year: 1989, vol: 86, page: 6913, stat: Journal Article,

Independent effects of diet and nutritional status on apoprotein B gene expression in rabbit
Fisher EA; Anbari A; Klurfeld DM; Kritchevsky D
1988 Nov-Dec;8(6):797-803, Arteriosclerosis
The separate effects of dietary composition and time of nutrient intake on apoprotein B (apo B) gene expression in rabbit intestine and liver were determined. After an overnight fast, there were insignificant effects of the long-term consumption of a diet containing saturated fat on the tissue levels of apo B mRNA, although plasma cholesterol levels were elevated as compared to those of animals consuming a diet containing unsaturated fat. However, when the animals were studied 2 hours after receiving a gastric tube feeding of a portion of their test diets after an overnight fast, there was a twofold increase in the intestinal apo B mRNA level and a similar increase in the transcriptional activity of the apo B gene independent of dietary composition. We conclude that, with the diets we used, nutrient intake alone has, in rabbits, a major effect on apo B gene expression at the level of transcription. This factor should be taken into account when designing studies of intestinal gene expression
— id: 37372, year: 1988, vol: 8, page: 797, stat: Journal Article,

Management of pheochromocytoma in sickle cell disease: case report
Fisher EA; Hubbard TW; Byrd RL; Solhaug MJ
1988 Feb;115(2):80-82, Virginia medical
— id: 37373, year: 1988, vol: 115, page: 80, stat: Journal Article,

Transcriptional activity of the genes for apoproteins A-I and E in neonatal rat liver
Fisher EA; Carroll RD; Cortner JA; Surrey S
1987 Dec;68(3):249-253, Atherosclerosis
The expression of the genes for apoproteins A-I and E (apoA-I, apoE) in fetal and neonatal rat livers was quantitated by measurement of steady-state levels of mRNA and by assays of relative transcriptional activity using the nuclear 'run-on' technique. From the last day of gestation (day -1) to day 5 after birth (day 5), for apoE there was a 2.2-fold increase in relative transcriptional activity and a 2.6-fold increase in steady-state mRNA. For apoA-I, from day -1 to 3 there was a 1.25-fold increase in both transcription and steady-state mRNA levels. We conclude that the increase in steady-state mRNA for the apoE gene which occurs during liver development in the rat is facilitated primarily by transcriptional control
— id: 37374, year: 1987, vol: 68, page: 249, stat: Journal Article,

Artifacts in RFLP analyses of human DNA samples co-precipitated with t-RNA
Fisher EA; Jung A; Cortner JS
1987 Dec;33(12):2304-2305, Clinical chemistry
— id: 37375, year: 1987, vol: 33, page: 2304, stat: Journal Article,

Comparison of the folding of beta-globin and ovalbumin gene containing chromatin isolated from chicken oviduct and erythrocytes
Fisher EA; Felsenfeld G
1986 Dec 2;25(24):8010-8016, Biochemistry
The dependence of chromatin conformation upon salt concentration has been studied for chicken ovalbumin and beta-globin genes isolated from oviduct and adult erythrocytes. At NaCl concentrations of 25 or 50 mM, the sedimentation properties, as a function of DNA size, of ovalbumin and globin chromatin are similar regardless of the source of the chromatin. In 100 mM NaCl, however, beta-globin chromatin isolated from erythrocytes sediments more slowly than an ovalbumin chromatin fraction from erythrocytes containing DNA of the same size. When the same experiment is carried out with material isolated from oviduct nuclei, the relative sedimentation rates are reversed, so that the ovalbumin chromatin sediments more slowly. This behavior cannot be accounted for by differences in binding of RNA polymerase or other molecules associated with transcription, or by partial aggregation of the chromatin. The most reasonable explanation is that transcriptionally active chromatin with a history of transcriptional activity, although largely covered with histones and capable of considerable compaction, is not able to form a fully compact structure as the ionic strength is raised. This behavior is consistent with a slight depletion in active chromatin of core histones or histone H1/H5 or both
— id: 37376, year: 1986, vol: 25, page: 8010, stat: Journal Article,

Serum alkaline phosphatase in diabetes mellitus
Maxwell DB; Fisher EA; Ross-Clunis HA 3rd; Estep HL
1986 ;5(1):55-59, Journal of the American College of Nutrition
Elevation of serum alkaline phosphatase concentration in patients with diabetes mellitus has been observed for several years, but the source and reasons are unknown. We report our experience with 39 diabetics, 38% of whom had an unexplained elevation of serum alkaline phosphatase. Isoenzyme determinations revealed bone fraction as the predominant species. Mean fasting serum glucose was significantly higher in the group with elevated alkaline phosphatase, supporting an association between the severity of diabetes and diabetic bone disease
— id: 37377, year: 1986, vol: 5, page: 55, stat: Journal Article,

Independent effects of dietary saturated fat and cholesterol on plasma lipids, lipoproteins, and apolipoprotein E
Fisher EA; Blum CB; Zannis VI; Breslow JL
1983 Aug;24(8):1039-1048, Journal of lipid research
Nine normolipidemic males (18-37 years) were fed formula diets containing (as % of calories) egg white protein (15%), glucose polymer:sucrose, 3:1 (54%), and fats (31%) as one of the following: corn oil (corn), corn oil plus 1 gram/day cholesterol (corn+), coconut oil (coco), coconut oil plus 1 gram/day cholesterol (coco+). Two dietary periods of 18 days each were separated by 1 month during which plasma lipid levels returned to prestudy values. A given dietary period consisted of 9 days of either corn or coco feeding allowed by 9 days of corn+ or coco+, respectively. Fasting plasma samples were taken the last 3 days of each 9-day interval. Lipids were determined by standard procedures and the apoE levels in lipoprotein fractions isolated by discontinuous density gradient ultracentrifugation were determined by radioimmunoassay. The biochemical variables measured were: total plasma, VLDL, IDL + LDL, and HDL, cholesterol, triglyceride, and apoE levels, as well as the apoE of plasma d greater than 1.17 g/ml. The effects of apoE phenotype, the type of dietary oil (corn versus coco), the presence or absence of dietary cholesterol, and the day of sampling within triplicates on the above variables were assessed statistically. The type of oil had the only significant effect on any variable. At P less than 0.01, the coconut oil diets were associated with significant elevations (as compared to corn oil) of the following nine variables: total, VLDL, IDL + LDL, and HDL cholesterol; total, VLDL, and IDL + LDL apoE; total and VLDL triglycerides
— id: 37378, year: 1983, vol: 24, page: 1039, stat: Journal Article,

Cysteamine in treatment of type III hyperlipidaemia?
Fisher EA; Gahl WA
1982 Nov 20;2(8308):1131-1132, Lancet
— id: 37379, year: 1982, vol: 2, page: 1131, stat: Journal Article,