Hypoglycemic activity in diabetic rats of stigmasterol and sitosterol-3-O--D-glucopyranoside isolated from Pseuderanthemum palatiferum (Nees) Radlk. leaf extract

Two major compounds, stigmasterol (ST) and sitosterol-3-O-β-D-glucopyranoside (SG) were isolated from Pseuderanthemum palatiferum leaf extract which is used traditionally as an antidiabetic. ST and SG at doses of 0.25 and 0.50 mg/kg were fed to diabetic rats for 21 days, and the fasting blood glucose (FBG) level and biochemical data on day 0, 4, 7, 10, 14, 17 and 21 were determined and compared with the anti-diabetic drug, glibenclamine. FBG levels at all doses of ST and SG were significantly decreased (p<0.05) with a concomitant increase in serum insulin. SG at the dose of 0.50 mg/kg showed the highest hypoglycemic effect. ST and SG also improved the following biochemical data and hematology parameters such as total cholesterol, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL), blood urea nitrogen, creatinine, red blood cells, platelet and white blood cells.   Key words: Pseuderanthemum palatiferum, acanthaceae, stigmasterol, sitosterol-3-O-β-D-glucopyranoside;, hypoglycemic activity.