Hyperactivation of the hypothalamo-pituitary-Adrenocortical axis in streptozotocin diabetic rats: Effect of Tinospora cordifolia (Willd.) and insulin therapy

Abstract

Aim: In the present study, we investigated the extent to which changes in corticosterone level and food and water intake behavior occur in diabetes and explored the effect of Tinospora cordifolia extracts and insulin therapy in streptozotocininduced diabetic rats. Materials and methods: Female albino rats of the inbred Wistar strain (body weight:180-210 g) were used in this study. Experimental diabetes was induced by injecting freshly prepared streptozotocin once at the dose of 55 mg/kg body weight intravenously in 0.1 M citrate buffer, pH 4.5. The drug was administered orally for 10 days and 30 days in different groups containing 6 rats in each group. Body weight, food intake, and water intake were monitored in each animal. Fasting blood glucose and plasma corticosterone levels were estimated. The efficacy of this drug was compared with lente zinc insulin (6 units/kg body weight daily, intraperitoneally) in treating diabetic rats. Results: There was a striking reduction in body weight, but elevated fasting blood glucose and corticosterone levels were observed in untreated diabetic rats during the study period. Elevated water and food intake was also prominent in these animals. Treatment with Tinospora cordifolia as well as insulin therapy could ameliorate all of these altered parameters toward normal. Conclusion: This study clearly showed that Tinospora cordifolia has a significant (P<0.05) effect in ameliorating all of these parameters toward normal in diabetic animals and has a level of efficacy that is considerably good compared to standard drug insulin. © TÜBITAK.