Roles of omega 3 fatty acids and chronic ethanol in the regulation of plasma and liver lipids and plasma apoproteins A1 and E in rats

Relative effects of feeding ethanol and/or omega 3 fatty acid-rich fish oil for 6 wk on body lipids and lipoproteins were investigated. Ethanol increased plasma cholesterol (P less than 0.06) and triglycerides (P less than 0.0005), whereas fish oil decreased plasma cholesterol (P less than 0.005) and triglycerides (P less than 0.02). Liver cholesterol and triglycerides were increased by ethanol (P less than 0.0001) while fish oil decreased liver cholesterol (P less than 0.01) but not triglycerides. Based on Scheffé contrasts (P less than 0.05), fish oil blocked the increases in liver cholesterol and triglycerides caused by ethanol. Substitution of normal dietary fat with omega 3 fatty acid-rich fat in ethanol-fed animals lowered plasma cholesterol by 29% (P less than 0.001) and triglycerides by 30% (P less than 0.05) within 2 wk. Plasma apo A1 was increased by ethanol (P less than 0.001) and decreased by fish oil (P less than 0.002). Plasma total apo E was unaffected by either ethanol or fish oil. However, HDL apo E was decreased by ethanol (P less than 0.04) and increased by fish oil (P less than 0.02). Scheffé contrasts (P less than 0.05) also showed that plasma apo A was increased by ethanol regardless of whether the animals were consuming regular fat (1.72-fold) or fish oil fat (1.49-fold). Thus, omega 3 fatty acids can not only prevent but also reverse many of the lipid and lipoprotein abnormalities caused by alcohol abuse in the rat.