Policosanol is a well-defined nutraceutical for the management of blood cholesterol levels. The present study examined (i) the effect of policosanol supplementation on blood cholesterol and glucose levels and (ii) changes in hepatic cholesterol biosynthesis using 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) activity in Wistar rats fed high cholesterol diets. The Wistar rats were assigned randomly to high-cholesterol diets (1.25% cholesterol) with or without policosanol (8.0 mg/kg body weight) for 6 weeks. Compared with the control group, dietary treatment with policosanol resulted in a significant decrease of blood cholesterol (p<0.01), blood glucose (p<0.01), triglyceride (p<0.001), and low density lipoprotein-cholesterol levels (p<0.01) and HMG-CoA reductase activity (p<0.001) in the liver. These results indicate that policosanol decreases blood cholesterol levels by suppressing cholesterol biosynthesis via decrease of HMG-CoA activity. Policosanol has the potential to be developed into an effective dietary strategy for both postprandial hyperglycemia and hypercholesterolemia.
Keywords: HMG-CoA reductase; blood glucose; hypercholesterolemia; low density lipoprotein-cholesterol; policosanol.