EFFECT OF POLICOSANOL ON IN-VITRO AND IN-VIVO RAT-LIVER MICROSOMAL LIPID-PEROXIDATION

Policosanol, a defined mixture of high molecular weight aliphatic alco hol isolated and purified from sugar cane (Saccharum officinarum, L) w ax is a new cholesterol-lowering agent effective in experimental model s, healthy volunteers, and patients with type II hypercholesterolemia. Also, policosanol prevents the onset of spontaneously-and experimenta lly-induced atherosclerotic lesions and cerebral ischemia in Mongolian gerbils. Free radicals are linked to many diseases including atherosc lerosis and ischemia/reoxidation cellular injury. Therefore, in this s tudy the authors evaluate the antioxidant activity of policosanol on r at liver microsomes. The extent of lipid peroxidation was measured by thiobarbituric acid reactive substances (TBARS). When policosanol was administered orally (100 and 250 mg/kg) for up to 4 weeks, a partial p revention of rat in vitro microsomal lipid peroxidation was noted. The formation of TBARS in microsomes isolated from treated rats was signi ficantly decreased by about 50%, when peroxidation was initiated by Fe 3+/ADP/NADPH, Fe2+/ascorbate and CCl4/NADPH-generating system. Also, o ral administration of policosanol in rats provides a partial inhibitio n of lipid peroxidation, but the mechanism supporting such effect rema ins to be elucidated. This beneficial effect of policosanol on membran e lipid peroxidation may be useful in protecting to some extent agains t free radical-associated diseases.