CHOLESTEROL AND UNSATURATED FAT DIETS INFLUENCE LIPID AND GLUCOSE-CONCENTRATIONS IN RATS

The present study investigated the effects of dietary cholesterol and monounsaturated and polyunsaturated fatty acids on plasma lipids and g lucose concentrations. Four groups of ten male Wistar albino rats were fed diets of different fatty acid composition for 40 days. The contro l group consumed nonpurified diet (containing fat 3.7 g/100 g diet), a nd cholesterol, olive oil, and safflower oil groups consumed the nonpu rified diet enriched with 14 g fat/100 g diet with egg yolk, I,live oi l, or safflower oil, respectively. Compared with the control, the diet enriched with cholesterol significantly increased fasting plasma chol esterol (P < 0.01), triacylglycerol (P < 0.01), total lipid (P < 0.01) and glucose (P < 0.05) concentrations; in the olive oil group, choles terol and triacylglycerol levels were significantly increased compared with control group (P < 0.01 in both instances). In safflower oil gro up, triacylglycerol levels were also significantly increased (P < 0.05 ) compared with the controls. After comparing diets providing the same amount of fat (cholesterol, olive oil, and safflower oil groups), hig her cholesterol, triacylglycerol and total lipid levels were observed in the cholesterol group than in the olive oil group (P < 0.01, P < 0. 05 and P < 0.01, respectively), and safflower oil group (P < 0.01 in a ll instances). High-density lipoprotein-cholesterol concentrations wer e significantly lower in the cholesterol group than in the olive oil a nd safflower oil groups (P < 0.05 in both instances) and fasting plasm a glucose levels were higher in the cholesterol than in the olive oil (P < 0.05) and safflower oil groups (P < 0.01). Finally, after compari ng lipid and glucose levels in the unsaturated fatty acids-enriched di ets, higher plasma cholesterol concentrations were observed in the oli ve oil than in the safflower oil group (P < 0.05). These data suggest that not only the amount but also the type of dietary fat can influenc e serum lipid levels.