title: Manganese superoxide dismutase gene expression and cognitive functions in recurrent depressive disorder.
abstract: BACKGROUND
  Recent studies have revealed that recurrent depressive disorders (rDD) are linked with dysregulation of the immune system. Previous studies have found that manganese superoxide dismutase (MnSOD, SOD2) may be a key inflammatory enzyme involved in this disorder. The purpose of this study was to determine the mRNA and protein levels of MnSOD in patients with rDD and to define the relationship between serum MnSOD levels and cognitive performance.
  
  
  METHODS
  The study comprised 236 subjects, which included patients with rDD (n = 131) and healthy subjects (n = 105, healthy control group, HC). Assessment of cognitive function was based on performance on the Trail Making test (TMT), the Stroop test, the Verbal Fluency test (VFT) and the Auditory Verbal Learning test (AVLT).
  
  
  RESULTS
  MnSOD gene expression at mRNA and protein level was significantly lower in rDD patients than in the HC group (p < 0.01). In the rDD and HC groups separately, there were no statistically significant associations between mRNA and protein expression levels of the MnSOD and psychological tests. In the total study group (n = 236), there was a statistically significant correlation between both MnSOD gene levels and the following tests (p < 0.01): the TMT parts A and B (negative correlation), the Stroop test parts RCNb (reading color names in black) and NCWd (naming color of word - different; negative correlation), the VFT (positive correlation) and the AVLT (positive correlation).
  
  
  CONCLUSIONS
  Our study provides evidence that the MnSOD enzyme-coding gene and MnSOD expression are important for the regulation of cognitive functioning.
authors.affiliation: Department of Adult Psychiatry, Medical University of Lodz, Lodz, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Talarowska
authors.forename: Agata
authors.initials: A
authors.lastname: Orzechowska
authors.forename: Janusz
authors.initials: J
authors.lastname: Szemraj
authors.forename: Kuan-Pin
authors.initials: KP
authors.lastname: Su
authors.forename: Michael
authors.initials: M
authors.lastname: Maes
authors.forename: Piotr
authors.initials: P
authors.lastname: Gałecki
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001244:Association; D003072:Cognition Disorders / Q000209:etiology*; D003866:Depressive Disorder / Q000097:blood* / Q000150:complications*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012333:RNA, Messenger / Q000378:metabolism; D013053:Spectrophotometry; D013482:Superoxide Dismutase / Q000097:blood* / Q000235:genetics*; D014706:Verbal Learning
chemical_list: D012333:RNA, Messenger; D013482:Superoxide Dismutase