Circulating zinc-α2-glycoprotein is reduced in women with polycystic ovary syndrome, but can be increased by exenatide or metformin treatment

Abstract

The study was to investigate circulating zinc-α2-glycoprotein (ZAG) concentrations in women with PCOS, and changes in ZAG levels after exenatide or metformin treatment. One hundred eighty-two women with polycystic ovary syndrome (PCOS) who met the 2003 Rotterdam diagnostic criteria and 150 controls without PCOS were recruited. We partitioned women with PCOS into groups according to body mass index or blood glucose concentrations, determined serum ZAG, anthropometric parameters, metabolic and endocrine indicators, and inflammatory markers, and statistically analyzed the results. Eighty-two overweight/obese subjects of the recruited women with PCOS were then randomly assigned to groups administered either 12 weeks of exenatide injection (10 μg b.i.d.) or oral metformin (1,000 mg b.i.d.). Circulating ZAG levels were determined after 12 weeks of treatment. The results showed that circulating ZAG was significantly lower in PCOS women than in healthy women (p < 0.01). Overweight/obese women and those with higher blood glucose levels had lower circulating ZAG. After 12 weeks of exenatide or metformin treatment, there were significant increases (p < 0.01) in circulating ZAG in both treatment groups (the exenatide baseline level was 46.54 ± 2.38 ng/mL vs. 56.41 ± 2.02 ng/mL after treatment, p < 0.01; metformin baseline was 47.81 ± 2.14 ng/mL vs. 55.67 ± 2.01 ng/mL after treatment, p < 0.01), however there was no statistical difference between the 2 treatments (p > 0.05). Circulating ZAG is closely related to PCOS and could be an important adipokine involved in the occurrence and development of PCOS. ZAG might possibly be applicable as a new observational indicator in the treatment of PCOS.