Increased plasma dipeptidyl peptidase-4 activities are associated with high prevalence of diabetic nephropathy in Chinese patients with newly diagnosed type 2 diabetes: A cross-sectional study

Objective:To investigate the association between plasma Dipeptidyl peptidase-4 (DPP4) activities and diabetic nephropathy in type 2 diabetes.Research design and methods:A total of 1193 newly diagnosed type 2 diabetic subjects were studied. Plasma DPP4 activity, mannose 6-phosphate receptor, inflammatory markers and oxidative stress parameters were measured in all participants. Diabetic nephropathy was defined as the presence of albuminuria or an estimated glomerular filtration rate < 60 mL/min/1.73 m2.Results:Participants in the highest quartile of DPP4 activity had higher HbA1c, homeostatic model assessment of insulin resistance, nitrotyrosine, 8-iso-PGF2a, interleukin-6, high-sensitivity C-reactive protein, mannose 6-phosphate receptor, urinary albumin-to-creatinine ratio and lower estimated glomerular filtration rate compared with participants in the lowest quartile (all p < 0.001). DPP4 activities were associated positively with HbA1c, homeostatic model assessment of insulin resistance, nitrotyrosine,...