Effect of saturated fatty acid-rich dietary vegetable oils on lipid profile, antioxidant enzymes and glucose tolerance in diabetic rats

Objective : To study the effect of saturated fatty acid (SFA)-rich dietary vegetable oils on the lipid profile, endogenous antioxidant enzymes and glucose tolerance in type 2 diabetic rats.
Materials and Methods : Type 2 diabetes was induced by administering streptozotocin (90 mg/kg, i.p.) in neonatal rats. Twenty-eight-day-old normal (N) and diabetic (D) male Wistar rats were fed for 45 days with a fat-enriched special diet (10%) prepared with coconut oil (CO) - lauric acid-rich SFA, palm oil (PO) - palmitic acid-rich SFA and groundnut oil (GNO) - control (N and D). Lipid profile, endogenous antioxidant enzymes and oral glucose tolerance tests were monitored.
Results : D rats fed with CO (D + CO) exhibited a significant decrease in the total cholesterol and non-high-density lipoprotein cholesterol. Besides, they also showed a trend toward improving antioxidant enzymes and glucose tolerance as compared to the D + GNO group, whereas D + PO treatment aggravated the dyslipidemic condition while causing a significant decrease in the superoxide dismutase levels when compared to N rats fed with GNO (N + GNO). D + PO treatment also impaired the glucose tolerance when compared to N + GNO and D + GNO.
Conclusion : The type of FA in the dietary oil determines its deleterious or beneficial effects. Lauric acid present in CO may protect against diabetes-induced dyslipidemia.

Keywords
Antioxidant enzymes, atherogenicity, coconut oil, glucose tolerance, palm oil, saturated fatty acid