Disrupted temperature-sleep coupling mechanism in a Dravet syndrome mouse model.

Dravet syndrome (DS) is associated with epilepsy, developmental delays, thermal dysregulation, and sleep disturbances. While seizures have been linked to hippocampal dysfunction, what drives sleep disturbances and thermal dysregulation is poorly understood. Using DS mice (Scn1aA1783V), we identified a link between sleep and thermoregulation. We found that DS mice exhibited lower core body temperature. Next, using electrocorticography, local field potential recordings, and core temperature monitoring, we showed that DS mice exhibited a lack of core temperature change during the transition from waking to non-rapid eye movement sleep. This is in contrast to wild-type (WT) mice, in which sleep onset coincided with a temperature drop. Additionally, warmth promoted sleep in WT, but not in DS mice. Vector-mediated expression of SCN1A or chemogenetic stimulation of the anterior hypothalamus restored the warmth-induced somnogenesis in DS mice. These findings highlight a connection between sleep and thermal dysregulation in DS, implicating altered neuronal activity of the hypothalamus.