Furthermore, the administration of TUDCA to mice with PCOS reduces the apoptosis of GCs in antral follicles, and this is associated with a concomitant decrease in the expression of CHOP and DR5, which implies that ER stress activated by HA in PCOS promotes the apoptosis of GCs via CHOP followed by caspase cascade and follicular growth arrest (27). This evidence concerns the gene DDIT3 and polycystic ovary syndrome.