RFRD2018- Prix de la meilleure présentation

Partenaire du XIVème Symposium National du Réseau Français de Recherche sur la Douleur (RFRD), BIOSEB a souhaité soutenir et valoriser les travaux d’un ou d’une étudiante en thèse en sponsorisant la remise d’un prix lors de l’évènement.

Toute l’équipe félicite ainsi Mademoiselle Inès DAGUET de l’université Claude Bernard de Lyon qui s’est vu décerner le prix de la meilleure présentation. Ses travaux portent sur l’influence du dérèglement des cycles circadiens sur la sensibilité à la douleur chez l’Homme:

How do Sleep and the Circadian Clock influence Sensitivity to Pain in Humans?

The reciprocal interaction between pain and sleep is established. The link between sensitivity to pain and circadian rhythmicity, however, is unknown. A few studies have suggested that healthy individuals present a 24-hour rhythm of sensitivity to pain, but the results are equivocal due to insufficient sampling rates. The objective of this study is to clarify whether sensitivity to pain is rhythmic in humans, and what the mechanisms involved are. 12 healthy individuals (20 – 30 years old) participated in a 56-h protocol, including 34 h of constant routine (CR). The CR protocol is considered as the gold-standard in chronobiology as it eliminates the influence of all environmental factors (sleep, posture, light, food intake...) and allows the endogenous circadian rhythmicity to appear. A polysomnography was conducted on night one, sleepiness and pain sensitivity were measured every 1-2 hours during CR. Experimental heat pain was induced on the participant’s forearm using a Peltier-type thermode (temperature at 46◦C for 2 seconds). Pain intensity was evaluated using a visual analogue scale. Our results show that pain sensitivity decreases during nocturnal sleep though it remains constant during sleep deprivation at night, suggesting an analgesic role of sleep. We also find a circadian rhythmicity of sleepiness (p< 0.0001) and pain sensitivity (p < 0.03)… This is the first evidence that sensitivity to pain follows a 24-hour rhythm that is driven by a dual influence from the biological clock (circadian control) and sleep pressure (homeostatic control).