Comparative analysis of the protective effects of melatonin and silymarin on lipid peroxidation and dyslipidemia in STZ-induced diabetic rats

ABSTRACT

Purpose of this study was to compare the potential protective effects of Melatonin and Silymarin on blood glucose, serum lipid profile, tissue MDA and tissue glutathione in streptozotocin [STZ] induced diabetic rats. Diabetes was induced in Wistar rats by administration of a single dose of streptozotocin [60 mg/kg, i.p.] injection. STZ treatment significantly increased the levels of blood glucose, serum total cholesterol [TCh], serum triglycerides [TG] and tissue malondialdehyde [MDA], a secondary product of lipid peroxidation. On the contrary high density lipoprotein [HDL] cholesterol and glutathione [GSH] content of liver and pancreas were markedly decreased in diabetic control rats, Administration of Melatonin [16 mg/kg] and Silymarin [25 mg/ kg] caused a significant decrease in blood glucose, serum triglycerides, total cholesterol and tissue MDA with significant increase in serum HDL-cholesterol and tissue GSH content of STZ induced diabetic rats when compared with diabetic control rats. Blood glucose, serum TCh, serum TG and tissue MDA lowering effect of Melatonin was greater than that of Silymarin. Melatonin was also found to be more potent than Silymarin in increasing HDL and GSH content. Based on our findings, it is possible to postulate that Melatonin at much lower concentration is more potent than Silymarin in controlling diabetes