title: Increased Postexercise Lipoxin A4 Levels in Exhaled Breath Condensate in Asthmatic Children With Exercise-Induced Bronchoconstriction.
abstract: BACKGROUND
  Lipoxins could be potential modulators of inflammation in the lungs. To our knowledge, the role of exhaled breath condensate (EBC) lipoxin A4 (LXA4) in asthmatic children with exercise-induced bronchoconstriction (EIB) has not been investigated.
  
  
  OBJECTIVE
  The aim of our study was to determine the involvement of EBC LXA4 in EIB.
  
  
  METHODS
  Forty-five patients aged between 5 and 17 years were included in the study. Patients were divided into 2 groups: asthmatic children with a positive response to exercise (n = 17) and asthmatic children with a negative response to exercise (n = 28). Levels of LXA4 were determined in EBC before and immediately after the exercise challenge using ELISA.
  
  
  RESULTS
  EBC LXA4 levels were significantly increased immediately after exercise in asthmatic children with a positive response to the exercise challenge (P = .05). No significant differences were observed in children with a negative response to exercise (P > .05). There was an inverse correlation between LXA4 levels and the percent degree of reduction in forced expiratory volume in the first second (FEV1%) postexercise in children with a positive exercise challenge (P = .05, r = -0.50). No significant differences were observed in LXA4 levels between atopic and nonatopic asthmatics (P > .05, Mann-Whitney U test).
  
  
  CONCLUSIONS
  Levels of EBC LXA4 increased immediately after exercise in asthmatic children with a positive exercise challenge response. We hypothesize that airway LXA4 levels increase to compensate bronchoconstriction and suppress acute inflammation, and that spontaneous bronchodilatation after EIB may be due to LXA4.
authors.forename: F
authors.initials: F
authors.lastname: Tahan
authors.forename: Gungor H
authors.initials: GH
authors.lastname: Eke
authors.forename: E
authors.initials: E
authors.lastname: Bicici
authors.forename: B
authors.initials: B
authors.lastname: Saraymen
authors.lastname: Akar H H
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001250:Asthma, Exercise-Induced / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D015415:Biomarkers / Q000378:metabolism; D001944:Breath Tests; D016084:Bronchoconstriction; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005080:Exercise Test; D045853:Exhalation; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D044045:Lipoxins / Q000378:metabolism*; D008168:Lung / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D044045:Lipoxins; C040527:lipoxin A4