TLR4 and polycystic ovary syndrome: SGD might reduce the phosphorylation of nuclear factor kappa-B (NF-kB) p65, suppress toll like receptor 4 (TLR4)/NF-kB signaling pathway, remodel gut microbiome structure, and protect gut barrier, which leads to ameliorate the inflammatory response in the ovary of PCOS rats [25, 33].