LONG-TERM EFFECTS OF DIETARY FIBER SUPPLEMENTATION ON SERUM GLUCOSE AND LIPOPROTEIN LEVELS IN DIABETIC RATS FED A HIGH CHOLESTEROL DIET

We have shown that cholesterol-fed diabetic rats developed atheromatou s lesions in the aorta and coronary arteries, which were not observed in cholesterol-fed diabetic rats receiving concomitant supplementation with 15% glucomannan, a soluble dietary fiber concentrate. The presen t study was designed to examine the effects of the dietary fiber suppl ementation on serum levels of glucose and lipoproteins in cholesterol- fed diabetic rats. Feeding a diet containing 1.5% cholesterol (wt/wt) and 0.37% cholic acid for 18 weeks to rats made diabetic by streptozot osin (35 mg/kg body weight, iv) produced moderate hyperglycemia and mo derate hypercholesterolemia, the latter being characterized by high co ncentrations not only of low density lipoproteins but also intermediat e density lipoproteins and very low density lipoproteins. These change s in serum lipoproteins and hyperglycemia were substantially reduced b y 18 weeks of supplementation with glucomannan but high density lipopr otein cholesterol and triglyceride levels did not change after feeding a cholesterol-rich diet in the presence or absence of glucomannan sup plementation. These results suggest that amelioration in hyperlipoprot einemia and hyperglycemia induced by the dietary fiber supplementation may help retard or prevent the atheromatous formation found in choles terol-fed diabetic rats.