title: Diet/Energy Balance Affect Sleep and Wakefulness Independent of Body Weight.
abstract: OBJECTIVE
  Excessive daytime sleepiness commonly affects obese people, even in those without sleep apnea, yet its causes remain uncertain. We sought to determine whether acute dietary changes could induce or rescue wake impairments independent of body weight.
  
  
  METHODS
  We implemented a novel feeding paradigm that generates two groups of mice with equal body weight but opposing energetic balance. Two subsets of mice consuming either regular chow (RC) or high-fat diet (HFD) for 8 w were switched to the opposite diet for 1 w. Sleep recordings were conducted at Week 0 (baseline), Week 8 (pre-diet switch), and Week 9 (post-diet switch) for all groups. Sleep homeostasis was measured at Week 8 and Week 9.
  
  
  METHODS
  Young adult, male C57BL/6J mice.
  
  
  RESULTS
  Differences in total wake, nonrapid eye movement (NREM), and rapid eye movement (REM) time were quantified, in addition to changes in bout fragmentation/consolidation. At Week 9, the two diet switch groups had similar body weight. However, animals switched to HFD (and thus gaining weight) had decreased wake time, increased NREM sleep time, and worsened sleep/wake fragmentation compared to mice switched to RC (which were in weight loss). These effects were driven by significant sleep/wake changes induced by acute dietary manipulations (Week 8 → Week 9). Sleep homeostasis, as measured by delta power increase following sleep deprivation, was unaffected by our feeding paradigm.
  
  
  CONCLUSIONS
  Acute dietary manipulations are sufficient to alter sleep and wakefulness independent of body weight and without effects on sleep homeostasis.
authors.affiliation: Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.|Neuroscience Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Isaac J
authors.initials: IJ
authors.lastname: Perron
authors.affiliation: Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Allan I
authors.initials: AI
authors.lastname: Pack
authors.affiliation: Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Sigrid
authors.initials: S
authors.lastname: Veasey
mesh_terms: D000818:Animals; D001835:Body Weight; D059305:Diet, High-Fat / Q000009:adverse effects; D004734:Energy Metabolism / Q000502:physiology*; D006706:Homeostasis; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology; D012895:Sleep, REM / Q000502:physiology; D014851:Wakefulness / Q000502:physiology*
keywords: diet switch; fragmentation; high fat diet; obesity; sleep