Hypoglycemic activity of the root and stem of Salacia reticulata var. β-diandra in alloxan diabetic rats

Abstract

The hypoglycemic activity of the aqueous extract of the root bark of Salacia reticulata (known as kotala himbatu) has previously been confirmed in the normal healthy rat model. In this investigation, molecules present in the powdered root and stem of Salacia reticulata Weight var. β-diandra were fractionated according to their polarity into several fractions by sequential extraction. Hypoglycemic potential of each fraction was evaluated, and the effect of active fraction was investigated in alloxan diabetic rats given long-term oral treatment. A significant hypoglycemic activity was established in the precipitate of methanol fraction, and it was used for the long-term oral treatment. Chronic oral administration of the precipitate from methanol fraction to alloxan diabetic rats twice a day for 120 days improved glucose tolerance and significantly reduced fasting blood glucose, fructosamine, and glycosylated hemoglobin levels. The polydypsia, hyperphagia, and weight loss of the alloxan diabetic rats were also reduced by the treatment. The results suggest that the hypoglycemic effect of Salacia reticulata in alloxan diabetic rats may involve an extrapancreatic effect on glucose production or clearance. © 2005 Taylor & Francis Ltd.