Antidiabetic and antioxidant activity of Terminalia belerica. Roxb.

Effect of continuous administration of dried 75% methanolic extract of fruits of Terminalia belerica (Combretaceae) suspended in water was studied in alloxan induced hyperglycemia and antioxidant defense mechanism in rats. T. belerica prevented alloxan-induced hyperglycaemia significantly from 6th day of administration and there was 54% reduction on 12th day. Oxidative stress produced by alloxan was found to be significantly lowered by the administration of T. belerica extract. This was evident from a significant decrease in thiobarbituric acid reactive substances, conjugated dienes and hydroperoxides in blood and liver respectively. Similarly, decreased glutathione level produced by alloxan was increased by the administration of the extract in blood and liver. However the increase was not significant. Superoxide dismutase which was decreased by alloxan was significantly increased from 9th day in blood and liver of drug treated group. Similarly there was significant increase in the activity of catalase in blood and liver. Decrease in glutathione peroxidase by alloxan administration was found to be increased significantly in the blood and liver from 9th day by extract treatment. Glutathione reductase also was found to be increased in blood and liver. These results suggested that T. belerica fruit extract possessed anti-diabetic and anti-oxidant activity and these activities may be interrelated.