Effects of Ethanolic Leaves Extract of Azadirachta indica Linn on Gene Expression of Streptozotocin-induced Hyperglycemic Wistar Rats (Rattus norvegicus Albinus)

Abstract

This study evaluated the effects of Azadirachta indica leaf extract on body weight and pancreatic insulin and glucagon gene expression in streptozotocin-induced hyperglycaemic male Wistar rats. Thirty-five adult male Wistar rats were assigned to five groups of seven animals each: a non-diabetic control group, an untreated diabetic control group, a diabetic group treated with metformin, and diabetic groups treated with A. indica leaf extract at 250 or 500 mg/kg body weight. Hyperglycaemia was induced using a single intraperitoneal dose of streptozotocin, and treatments were administered orally for six weeks. The extract was assessed for phytochemical and proximate composition, while body weight and blood glucose levels were monitored weekly. Pancreatic tissues were collected after treatment for molecular analysis of insulin and glucagon gene expression using RT-qPCR, with β-actin as the reference gene. Phytochemical analysis showed the presence of flavonoids, saponins, alkaloids, phenols, tannins, terpenoids, glycosides, steroids, oxalate, carbohydrates, monosaccharides, proteins, and amino acids, with steroids having the highest measured concentration (18.22 mg/g). Crude fibre was the most abundant proximate component. Untreated diabetic rats showed progressive body weight loss, whereas the treated groups showed improved body weight and reduced blood glucose levels compared with the untreated diabetic group; these differences were statistically significant (P < 0.05). The group treated with 500 mg/kg extract showed a higher percentage of insulin expression and a lower percentage of glucagon expression than the untreated diabetic group. These findings suggest that A. indica leaf extract may influence pancreatic gene-expression patterns in this experimental model.