Antidiabetic and antioxidant activity of Swietenia mahagoni in streptozotocin-induced diabetic rats

Context: Swietenia mahagoni L. Jacq. (Meliaceae) is a medium to large evergreen tree native to Southern Florida, Cuba, The Bahamas, Hispaniola, and Jamaica. Objective: To evaluate the antidiabetic and antioxidant potential of S. mahagoni bark. Materials and methods: In the present study, the antidiabetic activity of the methanol extract of S. mahagoni (MESM) bark in streptozotocin (STZ; 65 mg/kg body weight)-induced diabetic rats was evaluated. Glibenclamide (0.5 mg/kg; orally) was taken as the reference drug. The blood glucose levels and body weights were measured every 5th day over a period of 15 days. Antioxidant effects were assayed in diabetic rats by estimating thiobarbituric acid reactive substances (TBARS), glutathione (GSH), and catalase (CAT) levels. Results and discussion: Oral administration of MESM at the doses of 25 and 50 mg/kg b.w. resulted in a significant (p < 0.001) reduction in blood glucose levels in diabetic rats. Body weights were significantly (p < 0.001) reduced in STZ-induced diabetic rats when compared to normal rats, while the extract significantly restored body weight. The present study was further undertaken to evaluate the antioxidant activity of MESM in STZ-induced diabetic rats. Decreased levels of TBARS and increased levels of GSH and CAT activity indicated a reduction in free radical formation in tissues such as the liver and kidney of diabetic rats. Conclusion: These findings showed the significant hypoglycemic and antioxidant activity of the extract (MESM) in diabetic rats.