The correlation between zinc-α2-glycoprotein and adiponectin in population with different glucose tolerance

Objective To investigate the relationship of circulating zinc-α2-glycoprotein (ZAG) as well as adiponectin with adiposity and insulin resistance in humans.Methods Serum ZAG and adiponectin levels were determined by ELISA in 285 subjects with normal glucose tolerance (NGT),impaired glucose tolerance (IGT),and newly diagnosed cases with type 2 diabetes mellitus(T2DM).The relationships between circulating ZAG and insulin resistance or metabolic parameters were also explored.Results Circulating ZAG and adiponectin levels were all lower in T2 DM and IGT subjects than those in control subjects [ZAG:(37.14 ± 13.25 and 48.84 ± 18.74 vs 59.36 ± 16.20) mg/L,P＜0.05 or P＜0.01 ; adiponectin:(27.79 ± 11.23 and 33.00 ± 9.42 vs 41.81 ± 13.68) μg/L,P＜0.01].Circulating ZAG was correlated positively with high density lipoprotein-cholesterol and adiponectin (all P＜0.01),and inversely with body mass index,waist-hip ratio,FAT％,diastolic blood pressure,triglyceride,fasting blood glucose,fasting insulin,HbA1C,and homeostasis model assessment for insulin resistance(HOMA-IR,P＜0.05 or P＜0.01).By multivariate analysis,ZAG levels were independently associated with body mass index,HOMA-IR,diastolic blood pressure,and adiponectin (P＜0.05 or P＜0.01).Conclusions ZAG levels,associated with fat,insulin sensitivity,and adiponectin expression,are likely to play an important role in insulin resistance and energy homeostasis in humans. Key words: Zinc-α2-glycoprotein;  Adiponectin;  Insulin resistance;  Diabetes mellitus, type 2