title: Iron and iron-related proteins in the lower respiratory tract of patients with acute respiratory distress syndrome.
abstract: OBJECTIVE
  An increased oxidative stress in the lower respiratory tract of individuals with acute respiratory distress syndrome is considered to be one mechanism of lung injury in these patients. Cell and tissue damage resulting from an oxidative stress can ultimately be the consequence of a disruption of normal iron metabolism and an increased availability of catalytically active metal. Using bronchoalveolar lavage fluid, we quantified concentrations of iron and iron-related proteins in the lower respiratory tract in patients with acute respiratory distress syndrome and healthy volunteers.
  
  
  METHODS
  A clinical study to quantify iron and iron-related proteins in the lower respiratory tract in patients with acute respiratory distress syndrome and healthy volunteers.
  
  
  METHODS
  We studied 14 patients with acute respiratory distress syndrome and 28 healthy volunteers.
  
  
  RESULTS
  Comparable to previous investigation, protein, albumin, and cytokine concentrations in the bronchoalveolar lavage fluid were significantly increased in acute respiratory distress syndrome patients. The concentrations of total and nonheme iron were also increased in the lavage fluid of patients. Concentrations of hemoglobin, haptoglobin, transferrin, transferrin receptor, lactoferrin, and ferritin in the bronchoalveolar lavage fluid were all significantly increased in acute respiratory distress syndrome patients.
  
  
  CONCLUSIONS
  We conclude that bronchoalveolar lavage fluid indices reflect a disruption of normal iron metabolism in the lungs of acute respiratory distress syndrome patients. Increased concentrations of available iron in acute respiratory distress syndrome may participate in catalyzing oxidant generation destructive to the tissues of the lower respiratory tract. However, increased metal availability is also likely to elicit an increased expression of transferrin receptor, lactoferrin, and ferritin in the lower respiratory tract which will function to diminish this oxidative stress.
authors.affiliation: National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Ghio
authors.forename: Jacqueline D
authors.initials: JD
authors.lastname: Carter
authors.forename: Judy H
authors.initials: JH
authors.lastname: Richards
authors.forename: Lori D
authors.initials: LD
authors.lastname: Richer
authors.forename: Colin K
authors.initials: CK
authors.lastname: Grissom
authors.forename: Mark R
authors.initials: MR
authors.lastname: Elstad
mesh_terms: D000328:Adult; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D005260:Female; D006801:Humans; D007501:Iron / Q000032:analysis / Q000378:metabolism*; D033862:Iron-Binding Proteins / Q000032:analysis / Q000378:metabolism*; D008297:Male; D012128:Respiratory Distress Syndrome / Q000378:metabolism*
chemical_list: D033862:Iron-Binding Proteins; D007501:Iron