Vitamin E attenuation of the effects of chronic ethanol and cod liver oil consumption on rat liver lipid composition

We investigated the effects of dietary vitamin E supplementation on the modulatory actions of chronic ethanol and cod liver oil (CLO) feeding by measuring the fatty acid composition of hepatic lipids. Rats were fed diets that provided 35% of total calories as lipids and 36% of the calories as ethanol for 28 days. In these diets, cod liver oil replaced safflower, corn and olive oils low in omega-3-unsaturated fatty acids but high in the omega 6 unsaturated fatty acids. Some diets were also supplemented with 142 IU of vitamin E per kg of diet. Hepatic cholesterol, phospholipids and triglyceride levels were 30-100% greater in rats fed alcohol with or without vitamin E supplementation. Addition of dietary CLO reduced liver cholesterol and the cholesterol: phospholipid ratio but increased the phospholipid and triglyceride levels. Supplemental vitamin E in the CLO fed rats elevated the levels of hepatic phospholipids and cholesterol. The vitamin E-related alterations in hepatic lipids were also reflected by changes in hepatic fatty acid (FA) composition in rats fed ethanol and CLO. The alterations in the fatty acid profile indicated that both ethanol and CLO consumption altered hepatic FA profile. Ethanol metabolism by rats fed the Lieber-DeCarli (LD) diets increased hepatic levels of myristic, palmitoleic and oleic acid levels and decreased the level of linoleic acid despite diet type. Ethanol metabolism slightly decreased hepatic palmitate levels in rats fed the LD-diet but did not alter hepatic palmitate levels in rats fed the CLO-diets, and had no effect on hepatic stearate levels in rats fed the LD diet but significantly increased hepatic stearate levels in rats fed the CLO-diet. Hepatic oleic acid levels were not altered in rats fed ethanol in the CLO-diets.