3-nitrotyrosine and manumycin

Statins are presumed to exert their antiatherogenic effects in part via lipid-lowering-independent mechanisms. Inhibition of protein farnesylation and/or geranylgeranylation by statins has been postulated to contribute to the lipid-lowering-independent effects. However, a role for protein farnesylation in atherogenesis has not yet been studied. Therefore, we examined the effects of farnesyltransferase inhibitor, manumycin A, on the development of atherosclerosis in apolipoprotein E (apoE)-deficient mice fed a high-fat diet.. Manumycin A treatment for 22 weeks decreased Ras activity, and reduced fatty streak lesion size at the aortic sinus to 43% of that in vehicle-treated apoE-deficient mice (P<0.05), while plasma total cholesterol was unaltered. Moreover, manumycin A reduced alpha-smooth muscle actin-positive area to 29% of that in vehicle-treated apoE-deficient mice (P<0.01). The prevention of atherogenesis by manumycin A was accompanied by amelioration of oxidative stress, as judged by reduced ex vivo superoxide production and nitrotyrosine immunoreactivity.. These results indicate that the inhibition of farnesyltransferase prevents the development of mature atherosclerosis with concomitant alleviation of oxidative stress in apoE-deficient mice. The present data highlight farnesyltransferase as a potential molecular target for preventive and/or therapeutic intervention against atherosclerosis.

Topics: Animals; Apolipoproteins E; Atherosclerosis; Dietary Fats; Disease Models, Animal; Enzyme Inhibitors; Farnesyltranstransferase; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Muscle, Smooth, Vascular; Oxidative Stress; Phosphorylation; Polyenes; Polyunsaturated Alkamides; Protein Prenylation; Proto-Oncogene Proteins c-raf; ras Proteins; Sinus of Valsalva; Superoxides; Time Factors; Tyrosine