Antihyperglycaemic Properties of the Ethyl acetate Extract of Dennettia tripetala in Diabetic Rats

Abstract

Antihyperglycemic properties of chloroform (CDT), ethyl acetate (EDT) and methanolic (MDT) extracts of D. tripetala were investigated using alloxan- and streptozotocin-induced hyperglycemic rats. An oral glucose tolerance test (OGTT) was performed in EDT-pretreated in both normal and alloxan-induced hyperglycemic rats. Tolbutamide (TLB) was used as the reference drug. TLB (100 mg/g), EDT (100 mg/kg), MDT (100 mg/kg) significantly (p<0.05) decreased the plasma glucose level at different time intervals after the administration of the extracts/drug. The antihyperglycemic activity of TLB and EDT started at 2 and 3h, respectively, and lasted till 10h. EDT caused the highest reduction (46%) in plasma glucose level in 10h after treatment. In OGTT, EDT (50 mg/kg) significantly (p<0.05) increased glucose tolerance in both normal and hyperglycemic rats. This activity was more prominent in the alloxan-induced hyperglycemic rats. TLB (100 mg/kg) initially caused a slight reduction in plasma glucose level followed by steady level throughout the period of the study. Furthermore, EDT (30 mg/kg) significantly (P<0.05) decreased the plasma glucose level at 6, 8 and 10 h post treatment, when compared with TLB (100 mg/kg). In conclusion, EDT showed promising antihyperglycemic activity, which justified the use of the plant extract by the natives in managing diabetes mellitus.