期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2003
卷号：100
期号：3
页码：1262-1267
DOI：10.1073/pnas.0336398100
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Deficiency of acyl CoA:cholesterol acyltransferase 2 (ACAT2) in mice results in a reduction in cholesterol ester synthesis in the small intestine and liver, which in turn limits intestinal cholesterol absorption, hepatic cholesterol gallstone formation, and the accumulation of cholesterol esters in the plasma lipoproteins. Here we examined the contribution of ACAT2-derived cholesterol esters to atherosclerosis by crossing ACAT2-deficient (ACAT2-/-) mice with apolipoprotein (apo) E-deficient (ApoE-/-) mice, an atherosclerosis-susceptible strain that has impaired apoE-mediated clearance of apoB-containing lipoproteins. ACAT2-/- ApoE-/- mice and ACAT2+/+ ApoE-/- (control) mice had similar elevations of plasma apoB and total plasma lipids; however, the lipid cores of the apoB-containing lipoproteins in ACAT2-/- ApoE-/- mice contained primarily triglycerides rather than cholesterol esters. At 30 wk of age, only the control mice had significant atherosclerosis, which was nearly absent in ACAT2-/- ApoE-/- mice. ACAT2 deficiency in the apoE-deficient background also led to a compensatory increase in the activity of lecithin/cholesterol acyltransferase, the major plasma cholesterol esterification enzyme, which increased high-density lipoprotein cholesterol esters. Our results demonstrate the crucial role of ACAT2-derived cholesterol esters in the development of atherosclerosis in mice and suggest that triglyceride-rich apoB-containing lipoproteins are not as atherogenic as those containing cholesterol esters. Our results also support the rationale of pharmacological inhibition of ACAT2 as a therapy for atherosclerosis.
