Anti Diabetic activity of Terminalia superba (Combretaceae) Stem Bark Extract in Streptozotocin Induced Diabetic Rats

Aims: The present study was designed to evaluate the antidiabetic activity of the methanol stem bark extract of Terminalia superb (T. superba), a traditionally used medicinal plant in Cameroon.
Place and Duration of Study: Departement of Animal Biology and Physiology, Faculty of Science, University of Yaounde I, Cameroon and Laboratoire de Pharmacologie et Physiopathologie Expérimentales, Université Montpellier I, France. Between Ferbruary 2011 and September 2011.
Methodology: In one set of experiments, repeated doses of T. superba extract (37.5– 300mg/kg, p.o.) were administrated once daily for 21 days to groups of diabetic rats. In another set of experiments, acute effect of the plant extract (37.5–300mg/kg) in diabetic rats was evaluated.
Results: Following acute treatment, the plant extract produced a significant reduction in the blood glucose levels in diabetic rats. T. superba (75–300mg/kg) significantly decreased the blood glucose levels in glucose loaded rats. Oral administration of T. superba extract for 21 days resulted in a 31.43% and 21.42% significant reduction in blood glucose levels at the dose of 75mg/kg and 300mg/kg respectively. The plant extract significantly, reduced the plasma urea levels (20%) and induced a significant elevation in plasma insulin in treated rats. The extract did not significantly change elevated plasma cholesterol and triglycerides resulting from diabetic conditions.
Conclusion: The antidiabetic effect of the methanol stem bark extract of T. superba seems to be a result of increase in glucose utilization due to stimulatory action on insulin release.