Figure 4.

Significance of autophagy during the follicular atresia. Atresia is noticed during all the developmental stages of follicles; however, maximum atresia is observed at the antral stage. Autophagy contributes to follicular atresia by induction of apoptosis and/or autophagic cell death of granulosa cells. Activation of MAPK8 triggers autophagy by phosphorylation of apoptotic protein BCL2. Phosphorylated BCL2 is detached from the autophagy protein BECN1 and promotes autophagy. FSH hormone prevents oxidative stress damage by inhibiting autophagy via PI3K-AKT-MTOR pathway activation and mitophagy