Depletion of pulmonary EC-SOD after exposure to hyperoxia. Academic Article uri icon

Overview

MeSH

  • Acute Disease
  • Animals
  • Antioxidants
  • Extracellular Space
  • Gene Expression Regulation, Enzymologic
  • Mice
  • Mice, Inbred C57BL
  • Oxidative Stress
  • RNA, Messenger

MeSH Major

  • Hyperoxia
  • Pulmonary Alveoli
  • Respiratory Distress Syndrome, Adult
  • Superoxide Dismutase

abstract

  • Extracellular superoxide dismutase (EC-SOD) is highly expressed in lung tissue. EC-SOD contains a heparin-binding domain that is sensitive to proteolysis. This heparin-binding domain is important in allowing EC-SOD to exist in relatively high concentrations in specific regions of the extracellular matrix and on cell surfaces. EC-SOD has been shown to protect the lung against hyperoxia in transgenic and knockout studies. This study tests the hypothesis that proteolytic clearance of EC-SOD from the lung during hyperoxia contributes to the oxidant-antioxidant imbalance that is associated with this injury. Exposure to 100% oxygen for 72 h resulted in a significant decrease in EC-SOD levels in the lungs and bronchoalveolar lavage fluid of mice. This correlated with a significant depletion of EC-SOD from the alveolar parenchyma as determined by immunofluorescence and immunohistochemistry. EC-SOD mRNA was unaffected by hyperoxia; however, there was an increase in the ratio of proteolyzed to uncut EC-SOD after hyperoxia, which suggests that hyperoxia depletes EC-SOD from the alveolar parenchyma by cutting the heparin-binding domain. This may enhance hyperoxic pulmonary injury by altering the oxidant-antioxidant balance in alveolar spaces.

publication date

  • October 2002

has subject area

  • Acute Disease
  • Animals
  • Antioxidants
  • Extracellular Space
  • Gene Expression Regulation, Enzymologic
  • Hyperoxia
  • Mice
  • Mice, Inbred C57BL
  • Oxidative Stress
  • Pulmonary Alveoli
  • RNA, Messenger
  • Respiratory Distress Syndrome, Adult
  • Superoxide Dismutase

Research

keywords

  • Journal Article

Identity

Language

  • eng

Digital Object Identifier (DOI)

  • 10.1152/ajplung.00011.2002

PubMed ID

  • 12225954

Additional Document Info

start page

  • L777

end page

  • L784

volume

  • 283

number

  • 4