Increase in extracellular glutatione peroxidase in plasma and lungs of mice exposed to hyperoxia.


Journal Article

Extracellular glutathione peroxidase (E-GPx) is a selenium-dependent enzyme that can reduce hydrogen peroxide and phospholipid hydroperoxides. E-GPx is found in plasma and extracellular fluids such as bronchoalveolar lavage fluid. Because lung is one of the tissues that is capable of synthesizing and secreting E-GPx, the effect of exposure to hyperoxia on E-GPx in plasma and lung were studied in an injury model of hyperoxia exposure in adult mice. Exposure to 100% oxygen for 72 h resulted in an increase of 55% in plasma GPx activity and an increase of 50% in the amount of E-GPx protein in the plasma. Exposure to hyperoxia was also associated with an increase in the amount of E-GPx protein in lungs. The 7-fold increase in the amount of E-GPx protein in lungs was not due to plasma contamination of lungs from mice exposed to hyperoxia. E-GPx in the lung is calculated to account for 10% of lung GPx activity in control mice. However, E-GPx is calculated to account for 45% of lung GPx activity in the lungs of mice exposed to hyperoxia for 72 h. Further studies are needed to determine whether the increase in lung E-GPx is due to changes in translation or stability of E-GPx. The role of E-GPx in protecting the lung from oxidative damage warrants further study.

Full Text

Duke Authors

Cited Authors

  • Kim, KK; Whitin, JC; Sukhova, NM; Cohen, HJ

Published Date

  • December 1999

Published In

Volume / Issue

  • 46 / 6

Start / End Page

  • 715 - 721

PubMed ID

  • 10590029

Pubmed Central ID

  • 10590029

Electronic International Standard Serial Number (EISSN)

  • 1530-0447

International Standard Serial Number (ISSN)

  • 0031-3998

Digital Object Identifier (DOI)

  • 10.1203/00006450-199912000-00013


  • eng