Combined effects of quercetin and alpha-tocopherol on lipids and glycoprotein components in isoproterenol induced myocardial infarcted Wistar rats.

This study was aimed to evaluate the combined effects of quercetin and alpha-tocopherol on lipid metabolism and glycoprotein components in isoproterenol induced myocardial infarction in Wistar rats. Myocardial infarction in rats was induced by isoproterenol (100mg/kg) at an interval of 24h for 2 days. Quercetin (10 mg/kg) and alpha-tocopherol (10 mg/kg) were given to rats as pretreatment for 14 days orally using an intragastric tube. Quercetin and alpha-tocopherol significantly reduced the levels of cholesterol, triglycerides and free fatty acids in the serum and heart and serum phospholipids and significantly increased the levels of heart phospholipids in isoproterenol induced rats. They also significantly decreased the activity of plasma and liver 3-hydroxy-3-methylglutaryl-coenzyme-A reductase and increased the activity of plasma and liver lecithin cholesterol acyl transferase in isoproterenol treated rats. In addition to this, they also significantly reduced the levels of hexose, hexosamine, fucose and sialic acid in the serum and heart of isoproterenol treated rats. Quercetin and alpha-tocopherol also showed significant decrease in plasma lipid peroxidation products (thiobarbituric acid reactive substances and lipid hydroperoxides). Pretreatment with quercetin alone and alpha-tocopherol alone showed significant effect in all the biochemical parameters in myocardial infarcted rats. But, combined pretreatment with quercetin and alpha-tocopherol normalized all the above mentioned biochemical parameters in isoproterenol treated myocardial infarction in rats. Thus, the experiment clearly showed that quercetin and alpha-tocopherol prevented the accumulation of lipids and glycoprotein components in myocardial infarcted rats by their anti-lipid peroxidative effect. This study also showed that combined pretreatment was better than single pretreatment.