Our current research is focused on two main interconnected themes:
Differentiation and regulation of the pituitary gonadotrope function
Gonadotrope lineage specification depends on complex signaling and transcriptional cascades taking place in a coordinated manner during pituitary development that will also contribute to the regulation of the adult gonadotrope phenotype. We aim at understanding genetic and epigenetic mechanisms underlying such specification. Another objective is to understand how the gonadotrope cell deciphers the pulsatile secretion of GnRH, which orchestrates the reproductive life (contribution of miRNA, analysis of GnRH receptor signaling pathways and partners). In addition to GnRH, gonadotrope cells can be regulated by several other factors including signals linked to nutritional status. A topic recently developed in collaboration with the team REGLYS is to evaluate the direct impact of hyperlipidemia on pituitary gonadotrope function.
AMH and estradiol signaling in ovarian physiology and physiopathology
The anti-Müllerian hormone (AMH) was recently identified as a novel marker of the ovarian reserve and of granulosa cell tumors (GCT). Since then, and despite the massive increase in AMH use in clinical research and practice, the mechanisms of action and regulation of AMH in the ovary, remain elusive. We are studying ovarian AMH in physiological situations as well as in two pathologies characterized by high levels of AMH i.e. PCOS and GCT, in collaboration with the team’s clinicians. Another objective is to investigate the roles and mechanisms of action of 17beta-estradiol in the ovary, with a special emphasis on the regulation via non-genomic mechanisms of signaling pathways such as PI3K and MAPK. Synergistic action of AMH and estradiol on the progression of GCT is also evaluated.