IN-VITRO AND IN-VIVO ANTIDIABETIC EFFECTS OF 80 % METHANOL EXTRACT AND SOLVENT FRACTIONS OF THE LEAVES OF AJUGA INTEGRIFOLIA (LAMIACEAE) IN DIABETIC MICE MODELS

Abstract

Background: Diabetes mellitus, one of the major public health problems worldwide, is a metabolic disorder of multiple etiologies distinguished by a failure of glucose homeostasis with disturbances of carbohydrate, fat and protein metabolism as a result of defects in insulin secretion and/or insulin action. Ajuga integrifolia is used traditionally for the treatment of diabetes. Objective: To evaluate the in-vitro and in-vivo antidiabetic effect of 80 % methanol and solvent fractions extracts of the leaf of Ajuga integrifolia in diabetic mice models. Methods: The maceration technique was used for plant leaves extraction. The acute and sub-acute oral toxicity test of the plant was conducted according to the Organization for Economic Cooperation and Development. The in-vitro α–amylase inhibition and antioxidant activity of the 80 % methanol and solvent fractions extracts of the leaves of Ajuga integrifolia were evaluated by using 3, 5-dinitrosalicylic acid and diphenyl-2-picrylhydrazyl assay model, respectively. Blood glucose lowering activity of 250,500 and 1000 mg /kg body weight of the 80 % methanol and solvent fraction extract was studied in normoglycemic, oral glucose loaded, and streptozotocin induced diabetic mice model. Data were analyzed using Statistical Package for the Social Sciences software version 24. P-value<0.05 was considered statistically significant. Result: Acute and sub-acute toxicity study of 80 % methanol extract of the leaves of the Ajuga integrifolia did not show any sign of toxicity as well as mortality. Among the extract, 80 % methanol extract had a strong antioxidant activity (63.38±0.64%). The 80 % methanol extract of Ajuga integrifolia showed significant blood glucose lowering effect on normoglycemic and oral glucose loaded mice. The 80 % methanol extract and aqueous residues fraction had significant (p<0.001) antidiabetic activity at 1000mg/kg with 38.9% and 37.7% percent of blood glucose reduction in streptozotocin -induced diabetic mice model respectively. Conclusion: Acute and sub-acute treatment by 80 % methanol extract is safe and well-tolerated when taken by mouth. The 80 % methanol extract and aqueous solvent fraction of the leaves of the Ajuga integrifolia were demonstrated significant antidiabetic activity against streptozotocin induced diabetic mice models. The result in this study supported the traditional use of the Ajuga integrifolia leaves for the patients suffering from diabetes.