In the early 2000, two hypothalamic peptides belonging to the same RF-amide family, kiss peptin and RFRP, were reported to operate upstream of the GnRH neurons to regulate reproductive activity. In addition to reproductive activity, most species displays a strong seasonal variation in their metabolic activity and body weight. It was that photoperiod via melatonin regulates kisspeptin and RFRP to synchronize reproductive activity with seasons. Metabolic factors are also involved in the regulation of reproductive activity at different stages of life. The aim of this thesis project is to delineate how kisspeptin and / or RFRP are involved in the metabolic programming of reproductive function. The fundamental mechanism for the reciprocal control of energy metabolism and reproduction is still not known.
In the first part of the project we will investigate the role of Kp and / or RFRP on the seasonal regulation of body weight in the Siberian hamster. In the second part of the project we will investigate the effects of Kp and RFRP on glucose metabolism by using stable glucose isotope infusion and insulin clamp studies. The effects of Kp and RFRP will be investigated in both male and female as well as their dependency on sex steroids.
This project will be carried out in two teams of the NeuroTime network: in the Department of Hypothalamic Integration Mechanisms (Kalsbeek’s team, Amsterdam, The Netherlands) and the department of hypothalamic control of seasonal functions (V. Simonneaux’s team, Strasbourg, France).