A gatekeeping role of ESR2 to maintain the primordial follicle reserve.

A gatekeeping role of ESR2 to maintain the primordial follicle reserve. Endocrinology. 2020 Mar 06;: Authors: Chakravarthi VP, Ghosh S, Roby KF, Wolfe MW, Rumi MAK Abstract Over the entire reproductive lifespan in mammals, a fixed number of primordial follicles serve as the source of mature oocytes. Uncontrolled and excessive activation of primordial follicles can lead to depletion of the ovarian reserve. We observed that disruption of ESR2-signaling results in increased activation of primordial follicles in Esr2-null (Esr2-/-) rats. However, follicle assembly was unaffected, and the total number of follicles remained comparable between neonatal wildtype and Esr2-/- ovaries. While the activated follicle counts were increased in Esr2-/- ovary, the number of primordial follicles were markedly decreased. Excessive recruitment of primordial follicles led to premature ovarian senescence in Esr2-/- rats and was associated with reduced levels of serum AMH and estradiol. Disruption of ESR2-signaling through administration of a selective antagonist (PHTPP) increased the number of activated follicles in wildtype rats, whereas a selective agonist (DPN) decreased follicle activation. In contrast, primordial follicle activation was not increased in the absence of ESR1 indicating that the regulation of primordial follicle activation is ESR2-specific. Follicle activation was also increased in Esr2-mutants lacking the DNA-binding domain, suggesting ...
Source: Endocrinology - Category: Endocrinology Authors: Tags: Endocrinology Source Type: research