Circulating zinc-α2-glycoprotein levels are low in newly diagnosed patients with metabolic syndrome and correlate with adiponectin

Abstract Background Zinc-α2-glycoprotein (ZAG) is a novel adipokine that reduces insulin resistance, protecting against type 2 diabetes. However, past studies have been contradictory. This cross-sectional study aims to investigate the association of circulating ZAG with metabolic syndrome (MetS) in middle-aged and older Chinese adults. Methods Four hundred eighty nine individuals (234 healthy controls and 255 MetS patients) were examined. All individuals were screened for MetS according to the diagnostic guidelines of the United States National Cholesterol Education Program (NCEP) Expert Panel Adult Treatment Panel (ATP) III criteria. Circulating ZAG and ADI levels were measured by ELISA. Blood fat, glucose and insulin were measured with a commercial kit. Circulating ZAG levels were compared with various parameters in study subjects. Results Plasma ZAG levels were lower in MetS patients compared to those of the healthy controls (35.0 ± 11.7 vs. 46.1 ± 18.6 mg/L, P