Serum levels of the adipokine progranulin depend on renal function

Abstract

OBJECTIVE-Progranulinhas recently beenintroduced asanoveladipokine inducinginsulin resistance and obesity. In the current study, we investigated renal elimination, as well as association of the adipokine with markers of the metabolic syndrome. RESEARCH DESIGN AND METHODS-Progranulin serum levels were quantified by enzyme-linked immunosorbent assay and correlated to anthropometric and biochemical parameters of renal function and glucose and lipid metabolism, as well as inflammation, in 532 patients with stages 1-5 of chronic kidney disease (CKD). RESULTS-Median serum progranulin levels adjusted for age, sex, and BMI were significantly different between CKD stages with highest values detectable in stage 5 (stage 1, 58.3 μg/L; stage 2, 63.0 μg/L; stage 3, 65.4 μg/L; stage 4, 68.8 μg/L; and stage 5, 90.6 μg/L). Furthermore, CKD stage was the strongest independent predictor of circulating progranulin in our cohort. In addition, high-sensitivity interleukin-6 and adiponectin remained significantly and independently correlated with the adipokine. CONCLUSIONS-We demonstrate that progranulin serumlevelsincreasewith deteriorating renal function. These findings are in accordance with the hypothesis that renal clearance is a major elimination route for circulating progranulin. Furthermore, the adipokine is positively and independently associated with markers of inflammation and adiponectin.© 2013 by the American Diabetes Association.