title: Memory consolidation and inducible nitric oxide synthase expression during different sleep stages in Parkinson disease.
abstract: BACKGROUND
  Parkinson disease (PD) is a neurodegenerative disease characterized by motor and nonmotor dysfunctions, which include sleep disturbances. Rapid eye movement (REM) sleep is associated with numerous physiologic changes such as memory consolidation. Compelling evidence suggests that nitric oxide (NO) is crucial to both sleep regulation and memory consolidation. In our study, we explored changes in biologic molecules during various sleep stages and the effects of sleep on memory consolidation in PD.
  
  
  METHODS
  Ten PD patients and 14 volunteers without PD participated in our study. The gene expression of inducible NO synthase (iNOS) in all sleep stages was measured using realtime polymerase chain reaction (PCR) based on polysomnography (PSG)-guided peripheral blood sampling. In addition, the efficiency of memory consolidation during the sleep of the participants was measured using the Wechsler Memory Scale, third edition (WMS-III).
  
  
  RESULTS
  The iNOS expression increased in all sleep stages among the PD patients compared to the control participants, in whom iNOS expression decreased during REM sleep. Regarding memory consolidation, the performance of the controls in logic memory and the patients in visual reproduction tasks improved after sleep.
  
  
  CONCLUSIONS
  The iNOS synthase expression was different from control participants among PD patients, and the expression was dissimilar in various sleep stages. Sleep might enhance memory consolidation and there are different memory consolidation profiles between PD and control participants demonstrating distinct memory consolidation profiles.
authors.affiliation: Department of Neurology, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Sleep Center, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Dean
authors.initials: D
authors.lastname: Wu
authors.affiliation: College of Nursing, Taipei Medical University, Taipei, Taiwan.
authors.forename: Ing-Jy
authors.initials: IJ
authors.lastname: Tseng
authors.affiliation: Department of Neurology, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Rey-Yue
authors.initials: RY
authors.lastname: Yuan
authors.affiliation: Department of Neurology, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Sleep Center, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Department of Neurology, Taipei Medical University Hospital, Taipei, Taiwan; Sleep Center, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Chia-Yu
authors.initials: CY
authors.lastname: Hsieh
authors.affiliation: Department of Neurology, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Sleep Center, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; Department of Neurology, Taipei Medical University Hospital, Taipei, Taiwan; Sleep Center, Taipei Medical University Hospital, Taipei, Taiwan. Electronic address: chaurjongh@tmu.edu.tw.
authors.forename: Chaur-Jong
authors.initials: CJ
authors.lastname: Hu
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D008569:Memory Disorders / Q000235:genetics / Q000503:physiopathology; D008875:Middle Aged; D052247:Nitric Oxide Synthase Type II / Q000235:genetics* / Q000378:metabolism; D010300:Parkinson Disease / Q000235:genetics* / Q000503:physiopathology*; D017286:Polysomnography; D012894:Sleep Stages / Q000502:physiology*; D012895:Sleep, REM / Q000502:physiology; D014888:Wechsler Scales
chemical_list: C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II
keywords: Memory consolidation; NO; Parkinson disease; Polysomnography; REM sleep; iNOS