IRS1 and polycystic ovary syndrome: Catechins from oolong tea inhibited the expression of STAT3 signaling, MMP2, and MMP9 in the uterus, increased insulin receptor substrate-1 (IRS-1) and PI3K signals, and downregulated NF-κB, contributing to ameliorating hyperandrogenism and IR, reversing abnormalities in ovarian morphology and reducing uterine inflammation in insulin- and hCG-induced PCOS mice (Hong et al., 2020).