Anti-diabetic potential of Barleria lupulina extract in rats.

We have undertaken a study to evaluate the anti-hyperglycemic effect of a methanol extract of aerial parts of Barleria lupulina Lindl. (Acanthaceae) in streptozotocin-diabetic rats, based on folkloric reports its use as an anti-diabetic agent. The extract exerted significant (p < 0.05) anti-hyperglycemic efficacy at all levels tested from 4 h after its administration, as compared with the control group, and the effect was also prolonged up to 12 h. The extract at doses of 200 mg kg(-1) body wt. and above exhibited a maximum activity (p < 0.001) at 12 h after administration. The most significant activity (15.35% blood glucose reduction) was observed for the group administered 300 mg kg(-1) body wt. at 12 h after administration, while the standard drug glibenclamide (10 mg/kg(-1) body wt.) showed an 18.80% reduction of blood glucose at the same time interval. Based on our current results, it appears that the methanol extract of aerial parts of Barleria lupulina Lindl. shows a pronounced blood-glucose-lowering potential in streptozotocin hyperglycemic rats, and is thus provided with a pharmacological support of the folklore claims of anti-diabetic activity.