Ingestion of eicosapentaenoic acid-ethyl ester renders rabbit LDL less susceptible to Cu2(+)-catalyzed-oxidative modification.

The present study revealed that low density lipoprotein (LDL) obtained from rabbits fed highly purified eicosapentaenoic acid-ethyl ester (EPA-E) (EPA-LDL) was significantly less susceptible to oxidative modification catalyzed by Cu2+ as compared to LDL from rabbits fed a normal diet (control LDL). In a comparison of fatty acid composition of LDL, the contents of EPA and docosapentaenoic acid were significantly increased in EPA-LDL as compared to control LDL. The content of arachidonic acid (AA) was the same in both LDL groups. The contents of total cholesterol, free cholesterol, triglyceride, and phospholipid in LDL were unchanged by EPA-E ingestion. These data raise the possibility that EPA may protect LDL from oxidative modification, leading to a reduction of oxidized LDL in atherosclerotic lesions, and that this may be how EPA exert its anti-atherosclerotic action.