Gonadotropin releasing hormone antagonists suppress aromatase and anti-Müllerian hormone expression in human granulosa cells

Abstract

To investigate the effects of a gonadotropin-releasing hormone antagonist (GnRH-ANT) on the expression of anti-Müllerian Hormone (AMH) and aromatase (via the exon CYP19IIa promoter), in cultured human granulosa cells (hGCs) and the human granulosa cell line (HGL5). Primary cell cultures of hGCs and culture of HGL5 cells. Academic center. Women undergoing IVF because of male factor, tubal infertility, or donor eggs. hGCs and HGL5 cells were treated with a GnRH-ANT (1 nM and 1 μM) alone or in combination with cAMP (1 mM). Media was collected and stored at -80°C until assayed. mRNA levels of CYP19 IIa, AMH, steroidogenic factor 1 (SF-1) and liver receptor homologue-1 (LRH-1) were determined by quantitative polymerase chain reaction. ELISA was used to determined estradiol (E(2)) levels in the culture media. Pooled results from triplicate experiments were analyzed using one-way analysis of variance with Student-Newman-Keuls multiple-comparison methods. The GnRH-ANT decreased the expressions of CYP19 IIa, AMH, SF-1, and LRH-1. cAMP induced aromatase and AMH expression. Cotreatment with cAMP and GnRH-ANT caused a dose-dependent suppression of AMH and CYP19 IIa mRNA. A GnRH agonist (GnRH-A) increased the mRNA expressions of CYP 19 IIa and AMH. The GnRH-ANT decreased E(2) production in cultured hGCs. GnRH-ANTs, in addition to their central suppressive effects on the pituitary, may have a direct effect on ovarian granulosa cells with inhibition of aromatase and AMH expression. Furthermore, the inhibitory effect could be mediated via suppression of SF-1 and LRH-1, and may play a role in estrogen-mediated ovarian folliculogenesis.