title: Exhaled breath condensate formate after inhaled allergen provocation in atopic asthmatics in vivo.
abstract: OBJECTIVE
  The dual actions of S-nitrosoglutathione reductase comprise reduction of S-nitrosoglutathione, a potent endogenous airway smooth muscle relaxant that is depleted in asthmatics, and detoxification of formaldehyde to formate. Airway formate production is increased in children with asthma, suggesting increased activity of S-nitrosoglutathione reductase. We determined formate in exhaled breath condensate from adult atopic asthmatics with asthma exacerbation produced by inhaled allergen in vivo,
  
  
  METHODS
  Twenty-two adult atopic asthmatics underwent inhaled allergen challenge using specific allergen. Exhaled breath condensate was collected at baseline, 1 h after inhalation of the provocative dose of allergen, and then every 2 h for 8 h during the challenge. Formate was analyzed by ion chromatography,
  
  
  RESULTS
  Eleven asthmatics developed an isolated early airway response, and another 11 volunteers early response followed by late airway response (dual response). Formate concentrations doubled 1 h post-challenge in asthmatics with dual-airway response but essentially unchanged in patients with an isolated early reaction,
  
  
  CONCLUSIONS
  Dual-airway response to allergen in atopic asthmatics could be associated with increased activity of S-nitrosoglutathione reductase as suggested by greater concentrations of formate in exhaled breath condensate. Measurement of formate in exhaled breath condensate could serve as a noninvasive biomarker of S-nitrosoglutathione reductase activity in vivo. Our results need to be confirmed in a larger group of asthmatics.
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
authors.forename: Roby
authors.initials: R
authors.lastname: Greenwald
authors.forename: Brent A
authors.initials: BA
authors.lastname: Johnson
authors.forename: Aimee
authors.initials: A
authors.lastname: Hoskins
authors.forename: Ryszard
authors.initials: R
authors.lastname: Dworski
mesh_terms: D000328:Adult; D000445:Aldehyde Oxidoreductases / Q000276:immunology; D000485:Allergens / Q000008:administration & dosage; D001249:Asthma / Q000276:immunology* / Q000503:physiopathology; D001944:Breath Tests; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents / Q000008:administration & dosage; D045853:Exhalation; D005260:Female; D005561:Formates / Q000276:immunology*; D006801:Humans; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage; D055815:Young Adult
chemical_list: D000485:Allergens; D016085:Bronchoconstrictor Agents; D005561:Formates; D016210:Methacholine Chloride; D000445:Aldehyde Oxidoreductases; C087006:formaldehyde dehydrogenase, glutathione-independent