Evaluation of The Anti-Diabetic Effect of Aqueous Leaf Extract of Tapinanthus Butungii in Male Sprague-Dawley Rats

The prevalence of diabetes mellitus is between 2-7% of the population, increasing with age to between 10-14% of the patients aged above 40 years. Despite significant achievements in treatment modalities and preventive measures, the prevalence of diabetes has risen exponentially in the last decade. There is therefore a continued need for new and more effective therapies. Our aim was to evaluate the hypoglycemic, anti-hyperglycemic and anti-diabetic effects of aqueous extract of fresh green leaves of Tapinanthus butungii in rats.
Young adult, male Sprague-Dawley rats weighing 180-200 g were used. Diabetes mellitus was induced in the group of diabetic test rats by intraperitoneal injections of alloxan (150 mg/kg). Hyperglycemic state was induced by administration of subcutaneous injections of 50% Dextrose in water (5 g/kg). Single doses of aqueous leaf extract of Tapinanthus butungii (200, 300 or 400 mg/kg p.o.) were administered to normoglycemic, hyperglycemic and diabetic rats. The hypoglycemic, anti-hyperglycemic and anti-diabetic effects of these single doses were compared with those of glibenclamide (10 mg/kg), chlorpropamide (250 mg/kg), insulin lente (0.1 I.U./kg) and distilled water (2 ml/kg). Blood glucose levels were estimated before treatment, 0h, 1h, 2h, 4h, 8h, 10h and 12h after administration of extract.
Aqueous leaf extract of Tapinanthus butungii produced significant dose-dependent reductions (p < 0.05-0.001) in blood glucose concentrations of normoglycemic, hyperglycemic and diabetic rats comparable to glibenclamide, chlorpropamide and insulin.
Our results suggest that the leaves of Tapinanthus butungii have strong and remarkable anti-diabetic properties. Further studies are, however, required on the characterization of the constituents of the leaf extract of Tapinanthus butungii.