In PCOS patients, IRF7 causes low-grade chronic inflammation and IR through androgen-dependent TLR4/IRF-7/NF-κB signaling, and metformin targets this pathway to alleviate symptoms; IRF7 also modulates MCP-1 transcription in adipose tissue, resulting in macrophage aggregation and pro-inflammatory effects. Here, TLR4 is linked to polycystic ovary syndrome.