FMO5 and type 2 diabetes mellitus: Growing evidence suggests that dipeptidyl peptidase 4 (DPP‐4) inhibitors, beyond their role in improving glycaemic control, are helpful in ameliorating endothelial dysfunction in humans and animal models of T2DM.6, 7, 8 A recent meta‐analysis supports that DPP4 inhibitors could reduce the risk of adverse cardiovascular events and are safe from a cardiovascular standpoint in patients with T2DM.9 The mechanisms of DPP4 inhibitors in this setting are highly associated with decreased inflammation and NADPH oxidase‐related oxidative stress.8, 10