Oxygen toxicity in control and H2O2-resistant Chinese hamster fibroblast cell lines

Arch Biochem Biophys. 1990 Jun;279(2):249-60. doi: 10.1016/0003-9861(90)90489-l.


Following exposure to 95% oxygen, clonogenic cell survival was assayed and qualitative morphologic changes were observed in a Chinese hamster fibroblast cell line (HA-1). The time in 95% O2 necessary to clonogenically inactivate 90% of the cells was inversely related to the cell density of the cultures at the beginning of hyperoxic exposure (from 1 to 6 X 10(4) cells/cm2). The O2-induced loss in clonogenicity and evidence of morphologic injury were shown to be significantly delayed (17-22 h) in an H2O2-resistant variant of the parental HA-1 cell line. After the delay in onset of clonogenic cell killing or morphologic injury, the process of injury proceeded in a similar fashion in both cell lines. The H2O2-resistant cell line demonstrated significantly greater catalase activity (20-fold), CuZn superoxide dismutase activity (2-fold), and Se-dependent glutathione peroxidase activity (1.5-fold). The greater activities of CuZn superoxide dismutase and catalase were accompanied by similarly greater quantities of immunoreactive protein as determined by immunoblotting. These data demonstrate that the cells adapted and/or selected for growth in a highly peroxidative environment also became refractory to O2-induced toxicity, which may be related to increased expression of antioxidant enzymes. However, the magnitude of this cross-resistance to O2 toxicity was less than the magnitude of the cellular resistance to the toxicity of exogenous H2O2, suggesting that in this system the toxicity of 95% oxygen is not identical to H2O2-mediated cytotoxicity.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Blotting, Western
  • Catalase / metabolism
  • Cell Line
  • Cell Survival / drug effects
  • Cricetinae
  • Cricetulus
  • Drug Resistance
  • Female
  • Glutathione Peroxidase / metabolism
  • Hydrogen Peroxide / toxicity*
  • In Vitro Techniques
  • Microscopy, Electron
  • Ovary
  • Oxygen / toxicity*
  • Superoxide Dismutase / metabolism


  • Hydrogen Peroxide
  • Catalase
  • Glutathione Peroxidase
  • Superoxide Dismutase
  • Oxygen