Irisin as a mediator between obesity and vascular inflammation in Chinese children and adolescents.

BACKGROUND AND AIM

This study aims to characterize the role of Irisin in obesity and early onset metabolic and vascular sequelae in Chinese children. Furthermore, we aim to examine whether Irisin mediate endothelial cells dysfunction and vascular inflammation which eventually leads to obesity.

METHODS AND RESULTS

We quantified plasma Irisin levels using enzyme-linked immunosorbent assay (ELISA) among 85 lean and 120 obese children, and assessed the association of Irisin levels with anthropometric, metabolic, cardiovascular and inflammatory parameters of obese children comparing with lean children. We further characterized the markers for endothelial cells and inflammation between obese and lean children to assess potential correlations. In addition, a potential direct effect of Irisin on the expression of endothelial adhesion molecules was assessed in human coronary artery endothelial cells. Irisin levels from obese children was significantly lower than lean children, and this reduced Irisin levels is correlated with certain physical parameters of studied children. Moreover, we identified significant inverse associations between inflammation markers of endothelial activation with Irisin levels in obese children. Multiple regression analyses confirm Irisin serves as a strong predictor of SDS-SBP, Ang-2, ICAM-1, E-selectin and hsCRP levels, independent of SDS-BMI. Lifestyle intervention results in a significant improvement of these cardiovascular and inflammatory parameters, and these were accompanied by a significant improvement of Irisin levels and weight loss. Finally, in the mediation effect model, our data showed that Irisin changes act as partial mediators of the relationship between SDS-BMI changes and changes in inflammatory and endothelial parameters for ICAM-1, E-selectin and hsCRP after controlling for covariates. Likewise, on the cellular level, Irisin inhibition hsCPR, ICAM-1 and E-selectin expression in endothelial cells, whereas Ang-2, VCAM-1 and eNOS expression were unaffected.

CONCLUSIONS

Our study showed that Irisin levels change may indicate the early stages of cardiovascular disease in obese children.