Adipocytokines are associated with renal function in patients with normal range glomerular filtration rate and type 2 diabetes

Introduction: Adipocytokines represent a molecular link between metabolic factors and vascular function. The purpose of our study was to investigate the relationship between adiponectin, leptin and renal function parameters in patients with glomerular filtration rate (GFR) above 90 ml/min/m(2) and type 2 diabetes. Materials and methods: In 52 patients, plasma (P-) and urinary (U-) adiponectin and leptin were determined by radioimmunoassay and ELISA, respectively. Kidney function was assessed with GFR (plasma iohexol clearance) and albuminuria (radioimmunoassay). Results: The patients were aged 58 8 years and had a mean BMI value of 31.2 +/- 15.2 kg/m(2). Our measurements yielded the following values, expressed as median (25th percentile, 75th percentile): P-adiponectin 11.0 (7.1, 14.5) pg/ml, P-leptin 20.7 (9.6,35.9) ng/ml, U-adiponectin 0.8 (0.3, 1.2) mu g/mg creatinine, and U-leptin 1.0 (0.4, 1.9) mu g/mg creatinine. Albuminuria correlated with P-adiponectin (R = - 0.31, p = 0.03), and GFR correlated with U-leptin (R = - 0.32, p = 0.04). Conclusions: Adiponectin and leptin are associated with parameters of renal function already at the stage of apparently normal kidney function in type 2 diabetes. The exact mechanisms of the adipocyte-vasculature axis still remain to be elucidated. (C) 2009 Elsevier Ltd. All rights reserved.