Comparison of Antidiabetic Effects of Aqueous Extract of the Leaves and Fruits of Avicennia Marina in Streptozotocin-induced Diabetic Male Rats

Background: In this study, the anti-diabetic effect of the extract of leaves and fruits of Avicennia marina (A. marina) in streptozotocin (STZ)-induced diabetic male rats was investigated. Methods: An experimental study was conducted on 45 adult male rats in 9 groups of 5 rats. The control group received normal food only. Other groups were made diabetic by injecting them with 60 mg/kg intraperitoneal STZ injection. Diabetic groups were: one Sham Group (STZ only), one Positive Diabetic Group (STZ + 0.5 ml normal saline) and 6 experimental groups, treated with STZ plus 3 incremental doses (30, 60 and 120 mg/kg) of either leaves or fruits extract of A. marina for three consecutive days, using gavage method. 24 hours after the last extract administration, blood samples were taken from the rat hearts., the serum glucose and insulin levels were measured by glucose oxidase and ELISA methods, respectively, one week after the STZ injections and following 8-12 hours of fasting. Results: The extract of leaves and fruits of A. marina in all doses significantly decreased the serum glucose in diabetic rats compared to that in the Sham group. The extract of A. marina leaves at 30 mg/kg significantly increased the serum insulin level compared to that in Diabetic Sham Group. The extract of A. marina fruits at all doses significantly increased the serum insulin level in the Experimental Groups compared to the Sham Group (P <0.05). Conclusion: The extract of leaves and fruits of A. marina significantly reduced the serum glucose in STZ-induced diabetic rats.