title: Metabolomics applied to exhaled breath condensate in childhood asthma.
abstract: BACKGROUND
  Metabolomic analysis provides biochemical profiles of low-molecular-weight endogenous metabolites in biological fluids.
  
  
  OBJECTIVE
  The aim of this study was to assess the feasibility of nuclear magnetic resonance (NMR)-based metabolomic analysis applied to exhaled breath condensate ("breathomics"). Information coming from NMR spectra was analyzed with a view to establish the NMR variables that best discriminate between children with asthma and healthy children.
  
  
  METHODS
  Twenty-five children with asthma (17 with persistent asthma treated with inhaled corticosteroids, 8 with intermittent asthma inhaled corticosteroid naive; age, 7-15 yr) and 11 healthy age-matched control subjects were enrolled. Every child performed exhaled nitric oxide measurement, spirometry, and condensate collection. Condensate samples were analyzed by means of NMR spectroscopy. Linear and partial least squares discriminant analyses were applied to data obtained from the NMR spectra.
  
  
  RESULTS
  The combination of exhaled nitric oxide and FEV(1) discriminates children with asthma and healthy children with a success rate of approximately 81%, whereas selected signals from NMR spectra offer a slightly better discrimination (approximately 86%). The selected NMR variables derive from the region of 3.2 to 3.4 ppm, indicative of oxidized compounds, and from the region of 1.7 to 2.2 ppm, indicative of acetylated compounds.
  
  
  CONCLUSIONS
  Metabolomics can be applied to exhaled breath condensate, leading to the characterization of airway biochemical fingerprints. The presence of acetylated compounds suggests new metabolic pathways that may have a role in asthma pathophysiology.
authors.affiliation: Department of Pediatrics, University of Padova, 35128 Padova, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Carraro
authors.forename: Serge
authors.initials: S
authors.lastname: Rezzi
authors.forename: Fabiano
authors.initials: F
authors.lastname: Reniero
authors.forename: Károly
authors.initials: K
authors.lastname: Héberger
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Giordano
authors.forename: Stefania
authors.initials: S
authors.lastname: Zanconato
authors.forename: Claude
authors.initials: C
authors.lastname: Guillou
authors.forename: Eugenio
authors.initials: E
authors.lastname: Baraldi
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis* / Q000378:metabolism; D001944:Breath Tests; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D016022:Case-Control Studies; D002648:Child; D045853:Exhalation; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009569:Nitric Oxide / Q000032:analysis; D012130:Respiratory Hypersensitivity / Q000175:diagnosis* / Q000378:metabolism; D013147:Spirometry
chemical_list: D009569:Nitric Oxide