EFFECT OF SELENIUM ON LIPIDS AND SOME LIPID METABOLIZING ENZYMES IN DMBA INDUCED MAMMARY-TUMOR RATS

Current evidences clearly point out that an increase in lipid peroxida tion influences lipid metabolism in cancer patients. Several investiga tions recognize selenium as a potent antioxidant, as well as an antica rcinogen, in both animal and human systems. Selenium was administered to Wistar rats bearing mammary tumor induced by 7,12-dimethylbenz(a)an thracene (DMBA) to study alterations in the concentration of lipid pro files and in the activities of some lipid metabolising enzymes. Contro l and tumor-bearing rats administered with selenium, were fed 5 mg sod ium selenite/kg diet from the day of tumor induction. Plasma total lip ids, total cholesterol, free fatty acids, triglycerides, phospholipids , VLDL and LDL cholesterol were significantly lower in selenium-treate d rats bearing tumors, whereas, plasma ester cholesterol and HDL chole sterol were significantly greater due to selenium administration in DM BA induced-tumor rats. Total lipase and lecithin: cholesterol acyltran sferase registered greater activities in plasma of selenium administer ed rats with tumor, while the activity of preheparin lipoprotein lipas es in plasma of rats bearing tumors was lower due to selenium administ ration. These observations clearly indicate the effect of selenium in correcting the abnormalities of lipid metabolism in tumor-induced rats .