Antidiabetic Activity of Isolated Compound from Coccinia indica

  Background and Objective: Coccinia indica Wight. and Arn (Ivy gourd, family Cucurbitaceae) has a long tradition of use in the treatment of various ailments. Ayurveda and Unani systems claim C. indica as antidiabetic agent. Therefore the present investigation was aimed to evaluate antidiabetic activity of isolated compound(s) from C. indica. Materials and Methods: Methanol extract of C. indica aerial parts was prepared by Soxhlet extraction method and ethyl acetate fraction was prepared by partitioning of methanol extract. Ethyl acetate fraction was subjected to antidiabetic activity-guidedfractionation using column chromatography for the isolation of antidiabetic compound(s). Various fractions and isolated compounds were screened for antidiabetic activity using streptozotocin-nicotinamide type-2 diabetic model. The glucose level in rats was determined using glucometer. The antidiabetic biochemical estimations were performed on bioactive isolated compound. Results: Bioactivity-guided-fractionation yielded a bioflavonoid quercetin, which has been isolated for the first time from C. indica aerial parts. Quercetin (5 mg/kg, p.o.) significantly reduced the glucose levels in type-2 diabetic rats but did not produce hypoglycemic effects in oral glucose tolerance test on normal rats. Quercetin significantly increased insulin and serum HDL-cholesterol levels and showed better β-cell functions. Quercetin caused slight change in hepatic marker enzymes and kidney functions markers in diabetic rats. Conclusion: Quercetin is responsible for antidiabetic activity of C. indica aerial parts.