IRS1 and hyperinsulinism: In addition, LPS activates the serum kinase c-Jun N-terminal kinase (JNK) and the inhibitor of nuclear factor-κB kinase (IKK) to induce insulin receptor substrate-1 (IRS-1) serine phosphorylation, leading to impairment of the insulin metabolic pathway and triggering IR (Saad et al., 2016; Guadagnini et al., 2019), and hyperinsulinemia may interfere with follicular development, leading to excessive androgen production by follicular theca cells of the ovary, which consequently leads to PCOS.