24 However, our findings in this study are the first, to the best of our knowledge, to demonstrate that isoquercitrin inhibits DPP-IV in vitro and in vivo, resulting in enhanced GLP-1 and insulin secretion and then amelioration of hyperglycaemia in high-fat diet and STZ-induced T2DM mice. Here, GLP1R is linked to type 2 diabetes mellitus.