ANTIDIABETIC EFFECT OF n-HEXANE FRACTION OF HYDRO-METHANOLIC EXTRACT OF TAMARINDUS INDICA LINN. SEED IN STREPTOZOTOCIN-INDUCED DIABETIC RAT: A CORRELATIVE APPROACH WITH IN VIVO AND IN VITRO ANTIOXIDANT ACTIVITIES

The present study was carried out to evaluate antidiabetic as well as in-vivo and in-vitro antioxidant activities of n-hexane fraction of Tamarindus indica Linn. seed (T. indica) in streptozotocin (STZ) induced diabetic rat. Oral administration of n-hexane fraction at the dose of 100 mg/kg body weight for 28 days prevented significantly the STZ-induced hyperglycemia. The plasma insulin and C-peptide levels as well as activities of antioxidant enzymes such as catalase (CAT), peroxidase (Px) and superoxide dismutase (SOD) in the hepatic tissue were found to be decreased in diabetic animals which were corrected after the treatment of n-hexane fraction of hydro-methanolic extract of T. indica. Oral glucose tolerance test (OGTT) reveals that the fraction at above mentioned dose showed a significant decrease of blood glucose level in normal and diabetic rat. Histopathology of pancreas was performed after n-hexane fraction treatment to diabetic rat and the results were compared with the control as well as diabetic groups. To evaluate the free radical scavenging activities of the n-hexane fraction following in-vitro study model with ABTS [2, 2´-azino-bis(3-ethyl benzothiazoline-6-sulphonic acid)] and DPPH [1, 1-diphenyl-2-picrylhydrazyl] were carried out along with determination of IC₅₀ values 0.027±0.003 and 0.021±0.002 mg/ml respectively in respect to standard antioxidant such as butylated hydroxytoluene (BHT). Phytochemical studies reveal the presence of flavonoids, alkaloids, terpenoids and steroids in said fraction which is responsible for the possible antidiabetic and antioxidative actions. Acute toxicity study in rats did not show any signs of toxicity upto the dose of 3000 mg/kg body weight in rats.