ARG1 and diabetes mellitus: In this study, we found that (1) treatment with HGWWD for 2 weeks protected against diabetes-induced impairment of both hemodynamic function and vascular wall function, but did not alter blood glucose levels and body weight in diabetic mice; (2) HGWWD prevented diabetes-caused vascular endothelial dysfunction through arginase 1-NO signaling; (3) endothelial arginase 1 is a critical target for the prevention of HGWWD on vascular endothelial dysfunction in diabetic models.