Abstract

The α-glucosidase inhibitory and antioxidant activities of Bauhinia strychnifolia Craib in vitro have been explored; however, its effectiveness in vivo is still unknown. This study examined the hypoglycemic effects of B. strychnifolia extract. Acute toxicity was also investigated in mice using the up-and-down method. The experiments were carried out in both sexes of Wistar rats and female ICR mice. The results showed that the oral LD<inf>50</inf> of the plant extract was >5000 mg/kg. For the anti-diabetic investigation, diabetes was induced in rats by subcutaneous injection of alloxan (125 mg/kg). The hypoglycemic effect was evaluated by oral administration of the extracts (300, 500, and 750 mg/kg) to the diabetic rats once daily for 14 days. The results revealed that 500 and 750 mg/kg of the plant extract lowered blood glucose levels by 35.63% and 33.04%, respectively, on day 14. In addition, a 2-h oral glucose tolerance test was performed in normal rats, in which the extract (500 mg/kg, p.o.) did not control plasma glucose after glucose loading. In conclusion, the plant extract has low toxicity and the potential to act as an anti-diabetic drug. Its hypoglycemic effect may be the result of other effects unrelated to insulin secretagogue. However, the anti-diabetic effect might be due to the antioxidant and α-glucosidase inhibitory activities of the flavonoids constituents.