The increase of serum chemerin concentration is mainly associated with the increase of body mass index in obese, non-diabetic subjects.

Abstract

Chemerin is a newly discovered adipokine, whose circulating concentration is increased in obesity. To elucidate whether the increased circulating chemerin concentrations in obese subjects are associated with the increase of fat mass, the increase in chemerin gene expression in adipose tissue or both. Serum chemerin concentrations in 20 non-obese healthy volunteers and 21 non-diabetic obese subjects were measured using ELISA. Chemerin mRNA and chemerin protein levels in visceral and subcutaneous adipose tissues of obese subjects were analyzed by Real-Time PCR and Western blot respectively. We found that the serum chemerin concentrations were significantly higher in obese subjects than in controls and positively correlated with BMI, fat mass and body mass. Moreover serum chemerin concentrations were correlated positively with serum CRP concentrations independently of BMI. No correlation was found between the chemerin mRNA and chemerin protein levels in visceral and subcutaneous adipose tissues and BMI, fat mass, or body weight. Likewise, there was no correlation between the serum chemerin concentrations and the levels of chemerin mRNA and protein in adipose tissue of obese patients. Multiple regression analysis suggests that BMI was the main predictor of serum chemerin concentration. In contrast to chemerin, both serum leptin concentrations and adipose tissue leptin mRNA levels positively correlated with BMI. The results presented here indicate that serum chemerin concentrations correlated with BMI, whereas chemerin mRNA levels in adipose tissue did not. Thus the elevated circulating chemerin concentration in obese, non-diabetic patients was mainly associated with the increased BMI.