Systemic and ovarian inflammation in women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine/reproductive/metabolic disorder. The etiology of PCOS is complex and has been linked to low-grade chronic inflammation. Local inflammation of the ovary affects ovulation and induces or aggravates systemic inflammation. PCOS patients demonstrated significantly higher concentrations of circulating inflammatory cells, such as lymphocytes, neutrophils, eosinophilic granulocytes, monocytes and Th17 cells than women without PCOS, while the percentage of Treg cells was lower. Inflammatory factors, such as serum CRP, hs-CRP, IL-1Ra, IL-6, IL-17A, IL-17F, IL-18, IL-23, TNF-α, α-1 acid glycoprotein,monocyte chemoattractant protein-1 (MCP-1) and adipokines and their paralogs, including chemerin, C1q and TNF-related 6 (C1QTNF6), were also found to be significantly increased in the peripheral blood of PCOS patients. Levels of anti-inflammatory cytokines, such as IL-10, IL-17E, IL-27, IL-35 and IL-37, TGF-β, omentin-1, Secreted frizzled-related protein5 (SFRP5) were significantly lower. An analogous situation occurs locally in the ovary. Some vital inflammatory cells and cytokines may initially be released from the ovary and then enter the circulation. The systemic inflammation underlying PCOS is thought to interact with obesity, insulin resistance (IR) and hyperandrogenism. Traditional Chinese medicine, multitargeted treatment, anti-inflammatory and antioxidant medicine, and lifestyle modification can benefit PCOS women by alleviating inflammatory responses.