Plasma ceruloplasmin as a biomarker for obesity: A proteomic approach

Objectives: This study aimed to investigate new biomarkers of obesity particularly in relation with inflammation-associated proteins using protein differential display techniques. Design and methods: Comparison of protein expression in plasma between non-obese (n=109, body mass index, BMI < 25 kg/m(2)) and obese (n=32, BMI >= 25 kg/m(2)) groups was carried out using two-dimensional gel electrophoresis (2-DE) analysis. ELISA was also performed for validation. Results: Among six differentially expressed protein spots, ceruloplasmin (Cp) and fibrinogen were over-expressed in obese group. Plasma Cp levels were significantly higher in obese group than non-obese group (34.0 +/- 8.6 vs. 41.3 +/- 12.7 mg/dL, p < 0.001) and positively correlated with age (r=0.253, p < 0.005), BMI (r=0.265, p < 0.001) and hsCRP (r=0.385, p < 0.001). In stepwise multiple linear regression analysis, plasma Cp along with hsCRP were found predictors for obesity (adjusted beta-coefficient=0.266, p < 0.01). Conclusion: Elevated plasma Cp levels were significantly associated with obesity, which may be suggested to be a marker of obesity. (C) 2011 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.