title: Oxidative stress in schizophrenia: a case-control study on the effects on social cognition and neurocognition.
abstract: BACKGROUND
  Schizophrenia is a debilitating mental disorder that presents impairments in neurocognition and social cognition. Several studies have suggested that the etiology of schizophrenia can be partly explained by oxidative stress. However, our knowledge about the implications of oxidative stress on illness-related cognitive deficits is still far from being clear. The aim of this work was to study the role of oxidative stress molecules on social cognition and neurocognition in patients with schizophrenia.
  
  
  METHODS
  We assessed the peripheral levels of several molecules associated with oxidative stress, namely nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), homocysteine, superoxide dismutase (SOD) and neurotrophin 4/5 (NT4/5), in forty-one patients with schizophrenia and forty-three healthy participants. A battery of tests to measure neurocognition and social cognition was also administered to the schizophrenia group.
  
  
  RESULTS
  We found that the schizophrenia group presented substantially higher levels of oxidative stress than the control group, as revealed by elevated quantities of the pro-oxidants NO and MDA, and decreased levels of the antioxidants GSH, SOD and NT4/5. Interestingly, the levels of NT4/5, which have been shown to have antioxidant effects, correlated with executive functioning, as measured by two distinct tests (WCST and TMT). However, social cognition and symptom severity were not found to be associated with oxidative stress.
  
  
  CONCLUSIONS
  We propose a protective role of NT4/5 against oxidative stress, which appears to have a potentially beneficial impact on neurocognition in schizophrenia.
authors.forename: Cristina
authors.initials: C
authors.lastname: Gonzalez-Liencres
authors.forename: Cumhur
authors.initials: C
authors.lastname: Tas
authors.forename: Elliot C
authors.initials: EC
authors.lastname: Brown
authors.forename: Soner
authors.initials: S
authors.lastname: Erdin
authors.forename: Ece
authors.initials: E
authors.lastname: Onur
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Cubukcoglu
authors.forename: Omer
authors.initials: O
authors.lastname: Aydemir
authors.forename: Aysen
authors.initials: A
authors.lastname: Esen-Danaci
authors.forename: Martin
authors.initials: M
authors.lastname: Brüne
mesh_terms: D000293:Adolescent; D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology; D005260:Female; D005978:Glutathione / Q000378:metabolism; D006710:Homocysteine / Q000378:metabolism; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008875:Middle Aged; D009414:Nerve Growth Factors / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012559:Schizophrenia / Q000097:blood / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D012919:Social Behavior; D013482:Superoxide Dismutase / Q000378:metabolism; D055815:Young Adult
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D009414:Nerve Growth Factors; D017382:Reactive Oxygen Species; D006710:Homocysteine; D009569:Nitric Oxide; D008315:Malondialdehyde; D013482:Superoxide Dismutase; D005978:Glutathione