Effect of trigonella foenum graecum on Αlpha-glucosidase and dipeptidyl peptidase-iv inhibitory activity-an in vitro study

Abstract

Objective: The objective of this study is to find the effect of seed extract of Trigonella foenum graecum on the inhibition of α-glucosidase and dipeptidyl peptidase-4 (DPP-4) enzyme activity by in vitro method. Methods: Methanolic seed extract of T. foenum graecum seed was prepared and supplied by Sami Labs, Bengaluru, on request. For alpha-glucosidase inhibition assay, the following concentrations (0, 20, 40, 60, 80, and 100 µg/ml) of extracts and for DPP-4 inhibition assay (0, 5, 10, 20, 40, 80, 160, and 320d µg/ml) concentrations were used. The absorbance was measured at 540 and 405 nm using multiplate reader, and the percentage of α-glucosidase and DPP-4 enzyme inhibitory activity of extract fractions was calculated. Acarbose for alpha-glucosidase inhibition and vildagliptin for DDP-4 inhibition were used as standard drugs. The IC50 value for alpha-glucosidase inhibition and DPP-4 inhibition was determined. Results: The maximum alpha-glucosidase inhibitory activity of T. foenum graecum extract at 100 μg/ml was 68% (p<0.05) with IC50 value of 57.25 when compared to the acarbose (STD) of 94% with IC50 values of 42.78. The maximum percentage of DPP-4 inhibition of T. foenum graecum extract at 320 μg/ml is 77.84% (p<0.01) with IC50 value of 52.26 when compared to the vildagliptin (STD) it is 80.15% with IC50 value of 22.98. Conclusion: The results of the in vitro studies show that T. foenum graecum seed extract has significant alpha-glucosidase and DPP-4 inhibition. Further in vivo and clinical studies are necessary to establish the antihyperglycemic and antidiabetic potential of T. foenum graecum seed extract for the treatment of Type 2 diabetes mellitus.