title: Peripheral inflammatory cytokines as biomarkers in Alzheimer's disease and mild cognitive impairment.
abstract: BACKGROUND
  Several lines of evidence in the literature have shown that inflammation is involved in the pathogenesis of Alzheimer's disease (AD). However, the results from the evaluation of serum inflammatory markers in AD patients have been controversial.
  
  
  OBJECTIVE
  To determine if any differences exist in the monocytic secretion pattern of IL-1beta, IL-6, IL-12 and TNF-alpha from mild cognitive impairment (MCI) and AD patients, when compared with healthy age-matched controls.
  
  
  METHODS
  To evaluate the percentage of peripheral monocytes secreting IL-1beta, IL-6, IL-12 and TNF-alpha along with the relative levels of these proteins, a cytofluorimetric analysis was conducted under basal conditions and after lipopolysaccharide-induced cell activation.
  
  
  RESULTS
  We found, in AD and MCI patients, a significant raise in the percentage of monocytes producing the studied cytokines (under basal conditions and after the exposure to an inflammatory stimulus), as well as a decreased competence of these cells to respond to inflammatory challenges, when compared with controls.
  
  
  CONCLUSIONS
  These results agree with a persistent inflammatory status in AD, reinforcing the hypothesis of a progressive impairment of the immune response in this disorder and suggesting that monocytes may be good targets to study the progression from MCI to AD.
authors.affiliation: Center for Neuroscience and Cell Biology, Faculty of Medicine, Coimbra University, Coimbra, Portugal.
authors.forename: Rita João
authors.initials: RJ
authors.lastname: Guerreiro
authors.forename: Isabel
authors.initials: I
authors.lastname: Santana
authors.forename: José Miguel
authors.initials: JM
authors.lastname: Brás
authors.forename: Beatriz
authors.initials: B
authors.lastname: Santiago
authors.forename: Artur
authors.initials: A
authors.lastname: Paiva
authors.forename: Catarina
authors.initials: C
authors.lastname: Oliveira
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood*; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000097:blood*; D016207:Cytokines / Q000145:classification / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D007249:Inflammation / Q000139:chemically induced / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism
chemical_list: D015415:Biomarkers; D016207:Cytokines; D008070:Lipopolysaccharides