Effects of antioxidant vitamins along with atorvastatin and atorvastatin-niacin combination on diet-induced hypercholesterolemia in rats.

The present study investigated the effects of antioxidant vitamins along with atorvastatin and atorvastatinniacin combination on diet-induced hypercholesterolemia in rats. High cholesterol diet produced a significant increase in the serum total cholesterol, LDL-C, VLDL-C, TG, atherogenic index and decrease in HDL-C and HDL/LDL ratio. The lipid peroxidation and oxidative stress were significantly high in the hyperlipidemic control group. Atorvastatin improved atherogenic index but not the HDL/LDL ratio whereas atorvastatin-niacin combination improved both atherogenic index and HDL/LDL ratio. However, both atorvastatin and atorvastatin-niacin did not affect antioxidant status significantly. Co-administration of vitamin-E and vitamin-C along with atorvastatin and atorvastatin-niacin have improved serum lipid profile, prevented lipid peroxidation and improved antioxidant status. Addition of β-carotene along with lipid lowering drugs did not show additional benefits on serum lipid profile, lipid peroxidation and antioxidant status. Atorvastatin, atorvastatin-niacin combination when added with anti-oxidant vitamins, increased reduced glutathione level but did not affect MDA level, SOD and catalase activity in the liver tissue. Administration of both vitamin-E and vitamin-C along with atorvastatin-niacin therapy produced a significant improvement in the lipid profile as well as antioxidant status. Addition of β-carotene along with atorvastatin-niacin-vitamin-E-vitamin-C combination improved lipid profile but improvement was not as marked as observed with atorvastatin-niacin-vitamin-E-vitamin-C combination. The same beneficial effects of atorvastatin-niacin combination on lipid profile were not observed when it was combined with anti-oxidant vitamins especially β-carotene. The pro-oxidant role of β-carotene may be responsible for this effect.