acipimox and Atherosclerosis

Saturated fatty acids (FA) have been linked to an increased risk of cardiovascular disease. The effects of acipimox, a FA-lowering agent, on palmitate- (an important saturated fatty acid) stimulated atherosclerosis remains to be elucidated. We investigated the effects of acipimox on atherosclerosis in ApoE(-/-) mice fed a palmitate-rich diet. Male ApoE(-/-) mice, 6-8 weeks of age, were randomized into three groups. The animals were fed a normal chow diet in the control group, a diet containing 5% palmitic acid in the palmitate group, and a diet containing 5% palmitic acid and 0.02% acipimox in the acipimox group. The plasma lipid profiles, aortic lesions, plaque collagen content and the expression of matrix metalloproteinase (MMP)-2, MMP-3, MMP-9, and MMP-14 and the tissue inhibitor of MMP (TIMP)-1, and TIMP-2 were determined after a 12-week treatment. The palmitate-rich diet significantly increased plasma FA concentrations (P<0.01), enhanced atherosclerotic lesions (P<0.01), decreased plaque collagen content (P<0.01) and upregulated MMP-2 (P<0.05) in the aorta. Additionally, all of these harmful effects were significantly attenuated by co-treatment with acipimox (P<0.05 or P<0.01). The present study suggests that acipimox attenuates atherosclerosis and enhances plaque stability in ApoE(-/-) mice fed a palmitate-rich diet.

Topics: Animals; Apolipoproteins E; Atherosclerosis; Diet, Atherogenic; Hypolipidemic Agents; Male; Matrix Metalloproteinase 14; Matrix Metalloproteinase 2; Matrix Metalloproteinase 3; Matrix Metalloproteinase 9; Mice; Mice, Mutant Strains; Palmitates; Plaque, Atherosclerotic; Pyrazines; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinase-2

The advent of HIV protease inhibitors has greatly extended the life span of AIDS patients. With an aging HIV(+) population, the cardiometabolic side effects of these drugs are becoming increasingly important clinical concerns. The purpose of this study was to test the hypothesis that inhibition of adipose lipolysis will retard atherogenic lesion development induced by the antiviral protease inhibitors.. LDLR-null mice receiving ritonavir were compared with those receiving ritonavir plus lipolysis inhibitor acipimox or vehicle alone to determine how acipimox would affect ritonavir-induced atherogenesis. Intermittent high-fat high-cholesterol diet was used to facilitate optimal atheromatous lesion development. Drug effects were assessed as changes in aortic lesion score, plasma lipid and lipoprotein profile, body fat mass, and insulin-induced suppression of plasma fatty acid concentrations. Ritonavir increased aortic lesions, in association with decreased body fat mass, impaired antilipolysis action of insulin, and increased proatherogenic plasma lipoproteins. All these adverse effects were attenuated by cotreatment with acipimox.. Our results provide the first direct evidence that supports the hypothesis that dysregulation of adipose lipolysis is an important contributor to the proatherogenic role of selected HIV protease inhibitors.

Topics: Adipose Tissue; Animals; Antiretroviral Therapy, Highly Active; Atherosclerosis; Glucose; HIV Protease Inhibitors; Humans; Insulin; Lipids; Lipolysis; Mice; Mice, Knockout; Models, Biological; Pyrazines; Receptors, LDL; Ritonavir