Antidiabetic property and antioxidant potentials of aqueous extract of Azadirachta indica leaves in streptozotocin-induced diabetic rats
Ezeigwe Obiajulu Christian, Ezennaya Chidinma Felicia, Ifedilichukwu Nma Helen, Soronnadi Vivian Nneka, Chukwuemeka Ugochi Vivian and Alaebo Prince Ogochukwu
Objective: The study was conducted to investigate the effect of the aqueous extract of Azadirachta indica leaves on blood glucose levels, antioxidant enzymes and inhibition of lipid peroxidation in streptozotocin (STZ)-induced diabetic Wistar albino rats.
Materials and Methods: The phytochemical analysis was done using standard methods. Diabetes was induced by a single intraperitoneal administration of 50 mg/kg body weight of STZ. Fasting blood sugar levels of the experimental rats were measured at two days interval during the 28 days of treatment. The antioxidant enzymes were assayed using standard methods. Lipid peroxidation was determined by the thiobarbituric acid-reacting substances (TBARS) assay method.
Results: Phytochemical screening reveals the presence of saponin, flavonoids, phenols, cardiac glycosides, alkaloids and tannins. The result of the antidiabetic studies showed a significant (p< 0.05) reduction in the fasting blood glucose level of all the extract treated groups compared with diabetic untreated rats. The reduction in fasting blood glucose levels of the extract treated groups was consistently observable from day 6 to day 28 of the treatment. The serum catalase and glutathione peroxidase activities of rats treated with the extract showed a significant increase (p< 0.05) compared with the diabetic untreated control. There was a significant (p< 0.05) reduction in malondialdehyde level of all the extract treated groups compared with diabetic untreated group.
Conclusion: These results suggest that the aqueous extract of A. indica at varied doses has the potential to lower fasting blood glucose levels in streptozotocin-induced diabetic rats which can be as a result of the presence of certain phytochemicals responsible for the increase in the antioxidant enzyme activity of the experimental animals.