Antioxidant role of mulberry (Morus indica L. cv. Anantha) leaves in streptozotocin-diabetic rats

Background. The antihyperglycemic and antioxidant role of mulberry (Morus indica L.) leaves were investigated. Methods: Streptozotocin (STZ)-induced diabetic male Wistar rats were used as experimental models; one group was given 25% dry mulberry leaf powder mixed with the standard diet and another group was given standard diet for a period of 8 weeks. The antihyperglycemic and antioxidant role of mulberry was assessed by determining its effect on blood glucose, lipid peroxidation, reduced glutathione (GSH) concentrations and on the activity of glucose-6-phosphate dehydrogenase (G6PDH) and various antioxidant enzymes in erythrocytes and compared with that of controls. Results: Mulberry-treated diabetic rats showed a significant decrease in fasting blood glucose concentrations indicating a good glycemic control. Increased lipid peroxidation and the activity of catalase (CAT) in erythrocytes observed in diabetic controls were significantly decreased by mulberry leaves (48% and 33%, respectively). Decreased GSH concentrations and the activity of glucose-6-phosphate dehydrogenase and antioxidant enzymes viz., glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) and superoxide dismutase (SOD) observed in uncontrolled diabetes were improved (52%, 69%, 151%, 95%, 24% and 106%) by mulberry treatment very efficiently. Conclusion: Mulberry leaves possess antihyperglycemic and antioxidant properties. (C) 2003 Published by Elsevier B.V.