The insulinotropic activity of a Nepalese medicinal plant Biophytum sensitivum: preliminary experimental study.

The effect of the leaf extract of Biophytum sensitivum, an annual herb used in traditional Nepalese folk medicine for the treatment of hyperglycemic patients, was studied on glucose homeostasis in rabbits. In the first set of experiments, an acute effect of the extract on fasting plasma glucose (fpg) levels and serum insulin response was examined in non-diabetic and alloxan-diabetic rabbits. Initial dose-response studies showed that a dose of 200 mg/kg body weight (b.w.) was optimum for hypoglycemia. A single administration of this dose to 16-h fasted non-diabetic rabbits brought about a 16.1% fall in fpg at the end of 1 and 2 h, and the hypoglycemic effect persisted at the end of 6 h (13.8% fall). Serum insulin levels showed a significant rise in the treated animals, which suggested a pancreatic mode of action (i.e. insulinotropic effect) of B. sensitivum. The study of an acute effect of the extract in alloxan-diabetic rabbits, however, showed that it failed to produce such hypoglycemic or serum insulin response. In another set of experiments, administration of the above dose of the leaf extract attenuated the plasma glucose response to oral administration of 3 g/kg b.w. glucose load. The serum insulin levels in the treated animals showed a rise at the end of 2 (13.7% rise) and 6 h (12.6% rise). Taken together, these observations suggest that the hypoglycemic response of B. sensitivum may be mediated through stimulating the synthesis/release of insulin from the beta cells of Langerhans.