Frédérique Clément

REGATE Large Scale Project
SISYPHE project team
INRIA Paris-Rocquencourt Centre
BP 105 - 78153 Le Chesnay Cedex - FRANCE
e-mail : Frederique.Clement@inria.fr
phone : +33 1 39 63 53 83 - fax : +33 1 39 63 57 86
[FROG]
Puisqu'on ne peut être universel en sachant pour la gloire tout ce qui se peut savoir sur tout, il faut savoir peu de tout, car il est bien plus beau de savoir quelque chose de tout que de savoir tout d'une chose. Cette universalité est la plus belle.
Blaise Pascal, Pensées

Main Research Topic
Systems physiology of the hypothalamo-hypophyso-gonadal axis

Brief physiological background

In vertebrates, the neuroendocrine axes play a major part in controlling the main physiological functions (metabolism, growth, development and reproduction) and integrating internal or external environmental factors. The gonadotrope axis is made up of the hypothalamus, belonging to the central nervous system, the pituitary gland and the gonads (ovaries in females, testes in males). The reproductive function is a complex, tightly controlled physiological function, subject to many environmental cues such as the daylength, food availability and social interactions, as well as to internal signals such as stress or metabolic status. Specific hypothalamic neurons secrete, in a pulsatile manner, the GnRH (gonadotrophin releasing hormone), the "conductor" of the gonadotrope axis. The pulsatile GnRH secretion pattern ensues from the synchronisation of the secretory activity of individual GnRH neurons. The release of GnRH into the pituitarian portal blood induces the secretion of the luteinising hormone (LH) and follicle-stimulating hormone (FSH) by the gonadotroph cells within the pituitary gland. The gonadotrophins LH and FSH control the development of germinal cells within the gonads and their secretory activity. In turn, hormones secreted by the gonads (steroid hormones such as androgens, progestagens and oestrogens or peptidic hormones such as inhibin) modulate the secretion of GnRH, LH and FSH within entangled feedback loops. In females, the GnRH secretion pattern dramatically alters once per ovarian cycle, resulting in the GnRH surge characterised by massive continuous release of GnRH. The GnRH surge is responsible for the LH surge that triggers ovulation, leading to the release of fertilisable oocytes from ovarian follicles selected for ovulation.

Collaborating network

I am responsible for the coordination of the large scale project REGATE. REGATE lies at the border between Applied Mathematics, Control Theory and Computer Science on one hand, Physiology, Endocrinology and Cellular Biology on the other hand. It aims at disposing of interconnected, multi-scale models of the different organs building-up the gonadotrope axis and to be able to use them to take up physiological and clinical challenging questions. Starting from strictly biological motivations, the modelling approach gives rise to research questions in the fields of Applied Mathematics and Computer Science, dealing with the simulation and analysis of newly developed models or the solving of associated control problems. The project articulates on the coupling between different mathematical (mainly: conservation laws and dynamical systems) and computing (mainly: temporal logic and model checking) formalisms with biological knowledge and data.

Main publications in the field

Former research topics

[FROG]

last update 30/09/2011