Hypoglycaemic activity of aqueous extract of <i>Pentaclethra macrophylla</i> Benth. (Fabaceae) stem bark in streptozotocininduced diabetic rats

Abstract

The aqueous stem bark extract of Pentaclethra macrophylla Benth. (Fabaceae) was evaluated for hypoglycaemic activity in streptozotocin-induced diabetic rats. Diabetes was induced by streptozotocin, 50 mg/kg (i.p.) in fasted rats and the blood glucose levels were monitored at 0, 1, 2, 4, 8, 12 h and on the 14th day post treatment with the extract (250 and 500 mg/kg). Results showed that the extract (500 mg/kg) significantly reduced blood glucose in diabetic animals from the 4th h (p<0.01), 26.5% and was sustained throughout the entire period of the experiment. The maximum effect was seen at the 8th h (p<0.001), 38.6% and this was comparable to that of glibenclamide (p<0.001), 40.0%. The extract showed significant reduction in massive loss of body weights at 400 mg/kg (p<0.05) and 800 mg/kg (p<0.05) in diabetic rats. Phytochemical screening showed the presence of alkaloids, tannins, saponins, flavonoids and cardiac glycosides. Acute toxicity studies did not show any mortality at a dose of 10 g/kg. These results confirm the hypoglycaemic properties of the aqueous stem bark of P. macrophylla thus supporting the usage of the plant in traditional medicine in Eastern Nigeria in the treatment of diabetes mellitusKeywords: Hypoglycemic, streptozotocin, Pentaclethra macrophylla