The Potential Efficacy of Stevia Extract, Glimepiride and Their Combination in Treating Diabetic Rats: A Novel Strategy in Therapy of Type 2 Diabetes Mellitus

Background: The currently therapy of type 2 diabetes is unsatisfactory. Nowadays, there is a great interest in using the medicinal plants for treatment of diabetes. Therefore, we studied the efficacy of stevia extract alone and in combination with commonly used sulfonylureas ”glimepiride” in a trial to introduce a new effective therapeutic regimen for type 2 diabetes mellitus. Methods: Nicotinamide (230 mg/kg, IP) followed by streptozotocin (65 mg/kg, IP) were injected for induction of type 2 diabetes in male rats. The diabetic groups were treated for 21 days as the following, the first with stevia extract (300 mg/kg), the second with glimepiride (1 mg/kg), and the third with a combination of glimepiride and stevia extract. Many parameters were measured to evaluate the alleviation of the toxic effect of streptozotocin by stevia and/or glimepiride. Immunohistochemical expression of endothelial nitric oxide (eNOS) was assessed in renal tissues. Results: The stevia extract reduced the blood glucose, triglycerides, cholesterol, ALT, AST, urea, creatinine, tumour necrosis factor (TNFα) levels and malondialdehyde concentration compared to control diabetic group. Stevia treatment improved insulin and adiponectin levels. Stevia reduced eNOS expression in renal tissues compared to the diabetic rats. All these changes were more significant with combined treatment. Conclusion: Stevia and glimepiride may be a new putative therapeutic regimen for management of type 2 diabetes and its complications.