DPP4 and diabetes mellitus: Consistent with a report that patients with inflammatory metabolic states such as diabetes had increased levels of blood DPP4 activity [3], we observed that the levels of plasma DPP4 were higher in the nonCAD/DM(+) subjects than in that of the control subjects, suggesting a potential role of DPP4 in the pathogenesis of metabolic disease and the management of this disease.