Objective. Zinc- 2-glycoprotein (ZAG) has recently been proposed as a new adipokine involved in body weight regulation. The purpose of this study is to investigate serum levels of ZAG in patients with hypertension and its association with related characteristics. Methods. 32 hypertension patients and 42 normal controls were recruited and the relationship between serum ZAG, total and high molecular weight (HMW) adiponectin, and tumor necrosis factor- (TNF ) determined by enzyme-linked immunosorbent assay (ELISA) and metabolic-related parameters was investigated. Results. Serum ZAG concentrations were significantly lowered in patients with hypertension compared with healthy controls (61.4 ± 32 versus 78.3 ± 42？ g/mL, ). The further statistical analysis demonstrated that serum ZAG levels were negatively correlated with waist-to-hip ratio (WHR) ( , ) and alanine aminotransferase (ALT) ( , ). Additionally, serum HMW adiponectin significantly decreased, while TNF greatly increased in hypertension patients as compared with healthy controls (2.32 ± 0.41 versus 5.24 ± 1.02？ g/mL, 3.30 ± 1.56 versus 2.34 ± 0.99？pg/mL, ). Conclusions. Serum ZAG levels are significantly lowered in hypertension patients and negatively correlated with obesity-related item WHR, suggesting ZAG is a factor associated with hypertension. 1. Introduction Obesity is now a major health problem as it predisposes to insulin resistance, type 2 diabetes, cardiovascular malfunction, and cancer. Although the pathogenesis of obesity and its associated comorbidities are multifactorial, growing evidence suggests that altered production of adipose-derived protein factors (adipokines), such as leptin, tumour necrosis factor α (TNFα), adiponectin, and chemerin, plays an important role. For example, adipokines induce the functional and structural changes in the vessels by endothelial dysfunction, vascular smooth muscle cell (VSMC) proliferation and migration, and vascular inflammation, thereby regulating vascular responses to constrictor and dilator stimuli and contributing to the increased arterial pressure [1]. Zinc-α2-glycoprotein (ZAG, also called AZGP1) is a newly identified adipokine. Recent work from both our group and others has demonstrated ZAG levels in the serum and adipose tissue of obese patients and obese mice are significantly lower relative to subjects and mice of normal weights [2–4]. ZAG levels are negatively correlated with body weight and body fat mass [2, 5, 6]. The administration of ZAG in mice dramatically diminishes body weight and fat mass of normal, ob/ob, and high-fat-diet-
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