Chromium (VI) can activate and impair antioxidant defense system

Biol Trace Elem Res. 2011 Sep;142(3):388-97. doi: 10.1007/s12011-010-8806-y. Epub 2010 Sep 1.

Abstract

The changes in glutathione-dependent cycle enzymes and catalase activities under Cr(VI)-induced oxidative stress were investigated in two distinct cell lines: L-41-human epithelial-like cells and HLF-fetal human diploid lung fibroblasts, which differ in tissue origin, proliferation, and antioxidant enzymes activities. The chromium concentrations from 1 to 5 μM cause nontoxic effects and activate antioxidant enzymes to overcome oxidative stress. In spite of some differences in the endogenous antioxidant activities, both cell lines reveal the same range of toxic concentrations (20-30 μM). The irreversible inhibition of glutathione-dependent antioxidant enzymes develops under toxic concentrations and serves as a marker of toxicity. The endogenous antioxidant activity influences time-dependent expression of Cr(VI) toxicity and the dynamics of antioxidant enzymes activity under nontoxic conditions. The cell antioxidant defense system is an important marker of the cell adaptive capacity under nontoxic and toxic conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antioxidants / metabolism*
  • Catalase / metabolism
  • Cell Line
  • Chromium / toxicity*
  • Enzyme Activation / drug effects
  • Glutathione Peroxidase / metabolism
  • Glutathione Reductase / metabolism
  • Humans
  • Oxidative Stress / drug effects

Substances

  • Antioxidants
  • Chromium
  • Catalase
  • Glutathione Peroxidase
  • Glutathione Reductase