FFAR2 and polycystic ovary syndrome: Gut dysbiosis in PCOS patients is associated with reduced SCFA levels, which interact with G protein-coupled receptor 43 (GPCR43) and GPCR41 in enteroendocrine cells, intestinal epithelial cells, and pancreatic β-cells, increasing the secretion of glucagon-like peptide-1 (GLP-1) and peptide YY, regulating the hypothalamic-pituitary-gonadal axis, and altering luteinizing hormone and testosterone levels, thereby affecting the progression and phenotype of PCOS (Wang et al., 2021).