We investigated the role of brain lipid metabolism in higher brain functions including sleep regulations. Six-hour sleep deprivation markedly increased plasma ketone body concentration in mice. Moreover, sleep deprivation activated ketogenesis in the brain. We also found that icv injection of ketone bodies enhanced sleep depth and decreased glutamate release in freely moving mice. In the brain, astrocyte is known to produce ketone bodies from fatty acids. Lipid metabolism in the astrocyte may play a significant role in brain functions including sleep homeostasis.
