Insulin-like growth factor 2 is produced by antral follicles and promotes preantral follicle development in macaques.

Insulin-like growth factor 2 is produced by antral follicles and promotes preantral follicle development in macaques. Biol Reprod. 2020 Dec 21;: Authors: Tkachenko OY, Wolf S, Lawson MS, Ting AY, Rodrigues JK, Xu F, Bishop CV, Stouffer RL, Xu J Abstract Insulin-like growth factors (IGFs) are known for their involvement in endocrine and paracrine regulation of ovarian function. While IGF2 is the predominant circulating and intra-ovarian form of IGFs in primate species, the stage-specific follicular expression, action and regulation of IGF2 are not well defined. Therefore, experiments were conducted to investigate the follicular IGF production in response to steroid hormone regulation and the direct IGF actions on follicular development and function in vitro. Preantral follicles were isolated from rhesus macaque ovaries and cultured to the antral stage in media supplemented with follicle-stimulating hormone and insulin. Follicles were randomly assigned to treatment groups: (a) control, (b) trilostane (a steroid synthesis inhibitor), (c) trilostane + estradiol, (d) trilostane + progesterone, and (e) trilostane + dihydrotestosterone. Media was analyzed for IGF concentrations, which were correlated to follicle growth. Follicles produced IGF2, but not IGF1, at the antral stage. Steroid depletion decreased, while steroid replacement increased, IGF2 production by antral follicles. Media IGF2 levels correlated positively with antral follicle ...
Source: Biology of Reproduction - Category: Reproduction Medicine Authors: Tags: Biol Reprod Source Type: research