Androgens Modulate the Immune Profile in a Mouse Model of Polycystic Ovary Syndrome

Abstract Polycystic ovary syndrome (PCOS) is associated with a low‐grade inflammation, but it is unknown how hyperandrogenism, the hallmark of PCOS, affects the immune system. Using a PCOS‐like mouse model, it is demonstrated that hyperandrogenism affects immune cell populations in reproductive, metabolic, and immunological tissues differently in a site‐specific manner. Co‐treatment with an androgen receptor antagonist prevents most of these alterations, demonstrating that these effects are mediated through androgen receptor activation. Dihydrotestosterone (DHT)‐exposed mice displayed a drastically reduced eosinophil population in the uterus and visceral adipose tissue (VAT). A higher frequency of natural killer (NK) cells and elevated levels of IFN‐γ and TNF‐α are seen in uteri of androgen‐exposed mice, while NK cells in VAT and spleen displayed a higher expression level of CD69, a marker of activation or tissue residency. Distinct alterations of macrophages in the uterus, ovaries, and VAT are also found in DHT‐exposed mice and can potentially be linked to PCOS‐like traits of the model. Indeed, androgen‐exposed mice are insulin‐resistant, albeit unaltered fat mass. Collectively, it is demonstrated that hyperandrogenism causes tissue‐specific alterations of immune cells in reproductive organs and VAT, which can have considerable implications on tissue function and contribute to the reduced fertility and metabolic comorbidities associated with PCOS.