Linking altered gut microbiome to polycystic ovarian syndrome through immune mediated pathway

Polycystic ovarian syndrome (PCOS) is an endocrine disorder characterized by hyperandrogenism, ovulatory dysfunction, and metabolic disturbances. A balanced gut microbiome plays an important role in managing homeostatic signalling pathways in the body. These pathways regulate normal bodily functions but can become dysregulated under dysbiotic conditions. Recent research has highlighted the role of gut microbiota in the pathogenesis of polycystic ovarian syndrome. Key Bacterial taxa such as Akkermansia, Prevotella, Lactobacillus, Escherichia coli, Bacteroides and Ruminococcaceae (family-level) whose abundance is correlated with disease severity. At dysbiotic conditions, the pathobionts bypass the tight gut junction, enters the systemic circulation and trigger an immunomodulatory response subsequently releasing proinflammatory cytokines. Initially, first line and second line defence mechanisms are generated through immune responses such as IgG-mediated mechanisms. The immunological responses and inflammation cause macrophage pyroptosis, hormonal imbalance, and polycystic ovaries, followed by insulin resistance and hyperinsulinemia. Also, neuroendocrine alterations including dysregulation of GnRH secretion is influenced by gut-derived metabolites. The current review aids in understanding the mechanism pathway between gut microbiota and polycystic ovaries. Understanding ‘The Gut-PCOS axis’ explores various ways for targeting gut microbiota through prebiotics, probiotics and synbiotics as a potential therapeutic approach for polycystic ovarian syndrome management.