Effects of Diets on Serum and Liver Lipid Levels and Fatty Acid Composition of Liver Phospholipids in Rats

Effects of Diets on Serum and Liver Lipid Levels and Fatty Acid Composition of Liver Phospholipids in Rats

Serum and liver lipid levels and fatty acid composition of liver phospolipids (PL) were investigated in 36 rats which consumed either one of five different dietary fats or a high carbohydrate diet for 4 weeks. As the sources of five dietary fats, concentrated cicosapentaenoic acid(EPA), fish oil (FO), perilla oil(PO), corn oil(CO) and beef tallow (BT) were provided to the rats. As a control group, cron starch (CS) replaced dietary fat. The FO group showed lower serum total cholesterol (TC), high density lipiprotein cholesterol(HDL-C) and serum PL levels than those of the CO group(p<0.05). There were no significant differences in serum TC and serum HDL-C levels between the polyunsatured fatty acid(PUFA) groups and the EPA, FO and PO groups. The CS group showed the highest level serum TC. Compared with the CS group, both the EPA and CO groups showed significantly lower atherogenic indices(AI). However, there were no significant differences in AI among different dietary fat groups. No significant differences in liver triglyceride (TG) , TC and PL levels were detected among the six experimental groups. Phosphatidylcholine(PC) and phosphatidylethanolamine(PE) composed 30-40% and 15-20% of total liver PL, respectively. The fatty acid composition of liver PC and PE reflected dietary fatty acid composition . Compared to the different dietary fat based diets used in our study, the high carbohydrate diet had the most adverse effects on serum lipid profiles. However, we can not conclude from this result that long chain n-3 PUFA diets such as the EPA and FO based diets have more beneficial effects on serum lipid profiles than n-6 PUFA diet such as the CO based diet or shorter chain n-3 PUFA diets like the PO based diet.