title: The role of cytokines in physiological sleep regulation.
abstract: Several growth factors (GFs) are implicated in sleep regulation. It is posited that these GFs are produced in response to neural activity and affect input-output relationships within the neural circuits where they are produced, thereby inducing a local state shift. These GFs also influence synaptic efficacy. All the GFs currently identified as sleep regulatory substances are also implicated in synaptic plasticity. Among these substances, the most extensively studied for their role in sleep regulation are interleukin-1beta (IL-1) and tumor necrosis factor alpha (TNF). Injection of IL-1 or TNF enhances non-rapid eye movement sleep (NREMS). Inhibition of either IL-1 or TNF inhibits spontaneous sleep and the sleep rebound that occurs after sleep deprivation. Stimulation of the endogenous production of IL-1 and TNF enhances NREMS. Brain levels of IL-1 and TNF correlate with sleep propensity; for example, after sleep deprivation, their levels increase. IL-1 and TNF are part of a complex biochemical cascade regulating sleep. Downstream events include nitric oxide, growth hormone releasing hormone, nerve growth factor, nuclear factor kappa B, and possibly adenosine and prostaglandins. Endogenous substances moderating the effects of IL-1 and TNF include anti-inflammatory cytokines such as IL-4, IL-10, and IL-13. Clinical conditions altering IL-1 or TNF activity are associated with changes in sleep, for example, infectious disease and sleep apnea. As our knowledge of the biochemical regulation of sleep progresses, our understanding of sleep function and of many clinical conditions will improve.
authors: Department of VCAPP, Washington State University, Pullman 99164-6520, USA. krueger@vetmed.wsu.edu
authors: J M
authors: JM
authors: Krueger
authors: F J
authors: FJ
authors: Obál
authors: J
authors: J
authors: Fang
authors: T
authors: T
authors: Kubota
authors: P
authors: P
authors: Taishi
mesh_terms: D000241:Adenosine / Q000502:physiology; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000502:physiology; D002940:Circadian Rhythm; D016207:Cytokines / Q000502:physiology*; D005246:Feedback; D005786:Gene Expression Regulation; D013007:Growth Hormone-Releasing Hormone / Q000378:metabolism; D006133:Growth Substances / Q000502:physiology; D006801:Humans; D007375:Interleukin-1 / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology; D008959:Models, Neurological; D016328:NF-kappa B / Q000502:physiology; D009414:Nerve Growth Factors / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000502:physiology; D009473:Neuronal Plasticity; D009569:Nitric Oxide / Q000502:physiology; D017472:Receptors, Interleukin-1 / Q000187:drug effects / Q000502:physiology; D018124:Receptors, Tumor Necrosis Factor / Q000187:drug effects / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000187:drug effects / Q000502:physiology; D013569:Synapses / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology
chemical_list: D016207:Cytokines; D006133:Growth Substances; D007375:Interleukin-1; D016328:NF-kappa B; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D017472:Receptors, Interleukin-1; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D013007:Growth Hormone-Releasing Hormone; D000241:Adenosine