Pharmacological screening of antidiabetic activity of ethanolic extracts of justicia tranquebarensis on streptozocin induced rats.

Non-communicable diseases like diabetes mellitus are becoming major health problem these days. There is an increasing demand by patients to use the natural products (plants) with anti-diabetic activity due to the severe side effects associated with the use of insulin and oral anti-diabetic drugs. One such plant is Justicia tranquebareinsis which has been traditionally used for the treatment of diabetes mellitus. The aim of this study was, therefore, to evaluate hypoglycemic activity of ethanol extract of Justicia tranquebareinsis in streptozotocin-induced diabetic rats, respectively and to carry out acute toxicity test. Two doses (200 mg/kg and 400 mg/kg) of the ethanol extract of Justicia tranquebareinsis were administered to normal glucose loaded and diabetic rat to study blood glucose lowering effect. Ethanol extract of Justicia tranquebareinsis (200mg/kg and 400mg/kg, p.o.) showed significant tolerance (P < 0.05) to oral glucose load at 1 and 2 hrs after glucose load. The extract also produced significant (P < 0.05) blood glucose reduction at 4 hours after its administration in normoglycemic mice. The extract at 400mg/kg dose level produced significant (P < 0.05) reduction in blood glucose level at 2, 3 and 4 hours of treatment in streptozotocin (45 mg/kg) induced diabetic mice. Acute oral toxicity studies of ethanol extract of Justicia tranquebareinsis in rats showed no death or signs of toxicity at the dose of 2000 mg/kg indicating the safety nature of the extract. The results of the experiments showed that ethanol extract of Justicia tranquebareinsis has significant antihyperglycemic activity in streptozotocin induced diabetic rat and improvement in glucose tolerance and slight hypoglycemic activity in normal rat justifying the traditional claim for its use in diabetes.