Volume 3

July-September 2011

Evaluation of the anti-hyperglycemic activity of the crude leaf extracts of Sida acuta in normal and diabetic rabbits

C N Okwuosa, N C Azubike, Ii Nebo

The effect of the aqueous and methanol extracts of Sida acuta on blood glucose levels in both normal and diabetic rabbits was studied. The leaf extracts were screened for their effects on blood glucose levels in glucose overloaded rabbits. These extracts were also tested for anti-diabetic activity in alloxan-induced diabetic rabbits. Acute toxicity and preliminary phytochemical studies were performed. Results showed that both the aqueous extracts of S acuta (AESA) and the methanol extracts of S acuta (MESA) (400mg/kg) significantly increased the tolerance for glucose in glucose fed normal rabbits. Blood glucose was reduced significantly at 11/2 hrs post-glucose load (p<0.05). This reduction was consistent and persisted to 21/2 hrs. The positive control drug (glibenclamide, 0.5 mg/kg body weight, p.o) produced significant reduction on glycemia at 2 hours post glucose load (p<0.01). The methanol extract produced a significantly lower glucose concentration (mg.min/dl), as calculated from the area under the curve (AUC) of the glucose tolerance test, than AESA, glibenclamide and negative control respectively in the time periods 30-60 minutes, 60-90minutes and 90-150minutes (p<0.05; p<0.01). Both extracts (AESA and MESA) reduced blood glucose level in alloxanized rabbits significantly (p<0.05). The AESA and MESA (400mg/kg p.o) produced significant decreases in blood sugar at 4hours with percentage glycemic change of 30% and 20% respectively. The anti-hyperglycemic action of AESA and MESA were sustained up to 8 hours with significant percentage glycemic change of 46% and 45% respectively (P<0.01). Glibenclamide (0.5 mg/kg p.o) produced significant glucose reduction in alloxanized rabbits at 2 hours with a percentage glycemic change of 24.5% (P<0.01) and a percentage glycemic change of 40.4% at 8 hours. The crude leaf extracts of Sida acuta possess anti-hyperglycemic activity in diabetic and normal glucose fed rabbits.

Keywords: Sida acuta, Extracts, Alloxan, Anti-hyperglycemia.