Endocrine Abstracts

Purpose: Irisin is a secreted protein implicated in the regulation of insulin sensitivity and energy metabolism. Polycystic ovary syndrome (PCOS) is an inflammatory-based metabolic disease associated with insulin resistance, dyslipidemia, glucose metabolism dysfunction and obesity. There is also some evidence of a link between irisin and inflammation. Our aim of the study to ascertain whether the association of circulating irisin levels with inflammatory markers in PCOS.

Materials and Methods: A total of 128 women with PCOS and 128 age- and body mass index-matched female controls without PCOS were recruited for this cross-sectional study. Circulating irisin, UCP1, tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) levels were measured using ELISA; metabolic and hormonal parameters were also determined.

Results: Circulating irisin levels were higher in women with PCOS compared with controls (203.49±79.11 vs 169.82±66.05 ng/ml, P<0.001), whereas UCP1 levels were lower (31.41±12.57 vs. 38.34±15.29 pg/ml, P<0.001). The serum levels of inflammatory markers IL-6, TNF-α and hs-CRP were found to be significantly elevated in women with PCOS. Irisin levels were negatively correlated with UCP1 levels and positively correlated with inflammatory markers high-sensitivity C-reactive protein (hs-CRP), TNF-α, IL-6 and free-testosterone levels. Multiple linear regression analysis revealed that free-testosterone, UCP1, hs-CRP, TNF-α and IL-6 independently predicted irisin levels.

Conclusions: Increased irisin levels were associated with decreased UCP1 levels and elevated free-testosterone and inflammatory markers in PCOS patients, suggesting a possible connection between the irisin signaling pathway and inflammation in PCOS.