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

doi:10.1016/0003-9861(90)90489-L

Archives of Biochemistry and Biophysics

Volume 279, Issue 2, June 1990, Pages 249-260

https://doi.org/10.1016/0003-9861(90)90489-L Get rights and content

Abstract

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 × 10⁴ 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.

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

Abstract

Free Rad. Biol. Med

Mutat. Res

Arch. Biochem. Biophys

Arch. Biochem. Biophys

J. Biol. Chem

Exp. Cell Res

Anal. Biochem

Anal. Biochem

J. Biol. Chem

J. Biol. Chem

Biochem. Biophys. Res. Commun

J. Biol. Chem

Arch. Biochem. Biophys

Free Rad. Biol. Med

Exp. Cell Res

Free Rad. Biol. Med

Mutat. Res

Free Rad. Biol. Med

J. Appl. Physiol

Radiology

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