Background: Tribulus terrestris L. is a traditional herbal medicine used for treatment of hypertension, urinary tract inflammation, kidney and bladder stones. A few controversial experimental studies have been published regarding anti diabetic effects of its fruit extract.
Objectives: The present study was conducted to evaluate the effects of different doses of Tribulus terrestris (T.T.) fruit extract on rat blood glucose levels at acute and chronic phases compared with glibenclamide as the standard hypoglycemic drug.
Methods: 60 wistar male rats with 200-250gr weight were selected and caged in the same environmental condition. Diabetes was induced by 50mg/kg streptozotocin intraperitoneal (ip) injection. After 15 days the rats with fasting blood sugar (FBS) levels above 200mg/dl were selected and divided into 10 groups of 6 rats each. The T.T. fruit extract in doses of 15, 30, 60, 150, 250, 500, 750, 1000 mg/kg for acute phase and 500, 750, 1000 mg/kg for chronic phase (continuing of acute phase) were selected for ip injected in 8 groups. Glibenclamide (dissolved in 10% DMSO) 10 mg/kg was injected ip. The 10% DMSO solution was injected ip to control group. FBS and 2 hour post prandial blood sugar (2hrPPBS) levels were determined (by use of glucometer) every 20 days during 2 months of the study. Fasting blood insulin were determined at the end of the study.
Results: The results of this study indicate that the T.T. fruit extract at the doses of 750 and 1000mg/kg reduced FBS and 2hrPPBS levels significantly (p=0.000) compared to the glibenclamide and control groups.
Conclusion: T.T. fruit extract at the doses of 750 and 1000mg/kg has antihyperglycemic effects in diabetic rats.