title: Sleep deprivation impairs calcium signaling in mouse splenocytes and leads to a decreased immune response.
abstract: BACKGROUND
  Sleep is a physiological event that directly influences health by affecting the immune system, in which calcium (Ca(2+)) plays a critical signaling role. We performed live cell measurements of cytosolic Ca(2+) mobilization to understand the changes in Ca(2+) signaling that occur in splenic immune cells after various periods of sleep deprivation (SD).
  
  
  METHODS
  Adult male mice were subjected to sleep deprivation by platform technique for different periods (from 12 to 72h) and Ca(2+) intracellular fluctuations were evaluated in splenocytes by confocal microscopy. We also performed spleen cell evaluation by flow cytometry and analyzed intracellular Ca(2+) mobilization in endoplasmic reticulum and mitochondria. Additionally, Ca(2+) channel gene expression was evaluated
  
  
  RESULTS
  Splenocytes showed a progressive loss of intracellular Ca(2+) maintenance from endoplasmic reticulum (ER) stores. Transient Ca(2+) buffering by the mitochondria was further compromised. These findings were confirmed by changes in mitochondrial integrity and in the performance of the store operated calcium entry (SOCE) and stromal interaction molecule 1 (STIM1) Ca(2+) channels.
  
  
  CONCLUSIONS
  These novel data suggest that SD impairs Ca(2+) signaling, most likely as a result of ER stress, leading to an insufficient Ca(2+) supply for signaling events. Our results support the previously described immunosuppressive effects of sleep loss and provide additional information on the cellular and molecular mechanisms involved in sleep function.
authors.affiliation: Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil.
authors.forename: Lisandro
authors.initials: L
authors.lastname: Lungato
authors.forename: Marcos L
authors.initials: ML
authors.lastname: Gazarini
authors.forename: Edgar J
authors.initials: EJ
authors.lastname: Paredes-Gamero
authors.forename: Ivarne L S
authors.initials: IL
authors.lastname: Tersariol
authors.forename: Sergio
authors.initials: S
authors.lastname: Tufik
authors.forename: Vânia
authors.initials: V
authors.lastname: D'Almeida
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000502:physiology*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D008247:Lysosomes / Q000378:metabolism; D008297:Male; D053078:Membrane Potential, Mitochondrial; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008928:Mitochondria / Q000276:immunology* / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D012892:Sleep Deprivation / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D013154:Spleen / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D000071737:Stromal Interaction Molecule 1
chemical_list: D008565:Membrane Proteins; D009363:Neoplasm Proteins; C103530:STIM1 protein, human; D000071737:Stromal Interaction Molecule 1; D002118:Calcium