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.
©2011 Walter de Gruyter GmbH & Co. KG, Berlin/Boston
