Circadian clocks and metabolism

Team leader: Etienne Challet

The mammalian circadian system comprises a network of endogenous circadian clocks that generate an internal rhythmicity. At the top of the circadian system is a master clock located in the suprachiasmatic nuclei of the hypothalamus (SCN). Many circadian rhythms in behavior (e.g., sleep–wake cycle) and physiology (e.g., cyclic secretion of pineal melatonin and adrenal glucocorticoids) are controlled by this key structure. The suprachiasmatic clock is mainly synchronised (reset) by ambient light cues. Moreover, non-photic factors, such as metabolic or arousing cues, can also feedback to the main circadian clock in constant darkness or modulate its synchronisation to light. Furthermore, mealtime is a potent synchronizer of secondary clocks in central (e.g., the cerebellum) and peripheral organs (e.g., the liver).
Our team investigates functioning of the cerebral clocks and their resetting by feeding, metabolic and arousing signals with an integrative approach combining molecular biology and comparative physiology. Our main goal is to identify the pathways through which the brain clocks control the rhythmicity of physiological processes, such as the daily feeding/fasting cycle and meal anticipation, and how they are regulated by feeding and arousing cues.



Team projects



Members

Researchers / Professors / Assistant Professors

Etienne CHALLET

(DR2 CNRS)

Paul PEVET

(DRe CNRS, Pr conventionné Unistra)

Sylvie RAISON

(PU Unistra)

Patrick VUILLEZ

(MC HDR Unistra)

PhD students

Rosanna CAPUTO

co-supervision with Johanna Meijer
(Leiden Medical Center, NL)

Engineers

Stéphanie DUMONT- KIENTZY

(AI Unistra)



Selected publications

Challet E (2019). The circadian regulation of food intake. Nat Rev Endocrinol 15: 393-405.

Klosen P, Lapmanee S, Schuster C, Guardiola B, Hicks D, Pevet P, Felder-Schmittbuhl MP (2019). MT1 and MT2 melatonin receptors are expressed in non-overlapping neuronal populations. J Pineal Res 67: e12575.

Sen S, Dumont S, Sage-Ciocca D, Reibel S, de Goede P, Kalsbeek A, Challet E (2018). Expression of the clock gene Rev-erba in the brain controls the circadian organization of food intake and locomotor activity, but not daily variations of energy metabolism. J Neuroendocrinol 30: e12557.

Sen S, Raingard H, Dumont S, Kalsbeek A, Vuillez P, Challet E (2017). Ultradian feeding in mice not only affects the peripheral clock in the liver, but also the master clock in the brain. Chronobiol Int 34: 17-36.

Jha PK, Bouaouda H, Gourmelen S, Dumont S, Fuchs F, Goumon Y, Bourgin P, Kalsbeek A, Challet E (2017).
Sleep deprivation and caffeine treatment potentiate photic resetting of the master circadian clock in a diurnal rodent. J Neurosci 37: 4343-4358.

Delezie J, Dumont S, Sandu C, Reibel S, Pevet P, Challet E (2016) Rev-erba in the brain is essential for circadian food entrainment. Sci Rep 6: 29386.

Grosbellet E, Zahn S, Arrive M, Dumont S, Gourmelen S, Pevet P, Challet E*, Criscuolo F* (2015). Circadian desynchronization triggers premature cellular aging in a diurnal rodent. FASEB J 29:4794-4803.