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<25kg/m²) and obese (n=32, BMI<25kg/m²) 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 β-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.