Synergistic Action in Oral Glucose Tolerance Tests between Spilanthes Calva Aerial Parts and Tubers of Colocasia Esculenta

Abstract

Introduction: Diabetes is a debilitating disease characterized by elevated blood glucose levels, which is rapidly r eaching endemic proportions throughout the world including Bangladesh. We had previously evaluated the antihyperglycemic potential of methanolic extract of aerial parts of Spilanthes calva and tubers of Colocasia esculenta. The objective of this study was to determine whether there is any synergistic antihyperglycemic activity between the methanolic extracts of the plant parts of the two plants.Methods: Antihyperglycemic activity and synergistic potential were determined through oral glucose tolerance tests (OGTT) in mice.Result: Administration of methanolic extract of aerial parts of S. calva (MESC) at a dose of 400 mg per kg body weight led to lowering of blood glucose levels in glucose-loaded mice in OGTT by 41.6%. At the same dose, methanolic extract of tubers of C. esculenta (MECE) lowered blood glucose levels by 25.1%. At doses of 100, 200 and 400 mg each of (MESC + MECE), blood glucose levels in mice were lowered, respectively, by 38.8, 43.0, and 49.5%. At the highest dose of the combination, the reductions in blood glucose were comparable to that of a standard antihyperglycemic drug, glibenclamide, which when administered at a dose of 10 mg per kg lowered blood glucose by 52.2%. Conclusion:Synergistic antihyperglycemic activity was observed between aerial parts of S. calva and tubers of C. esculenta in oral glucose tolerance tests. The combination has the potential to be a substitute for glibenclamide.