Glutathione peroxidase, superoxide dismutase, and catalase inactivation by peroxides and oxygen derived free radicals

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Abstract

Glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase are the most important enzymes of the cell antioxidant defense system. However, these molecules are themselves susceptible to oxidation. The aim of this work was to estimate to what extent this system could be inactivated by its own substrates. We tested the effect of hydrogen peroxide, cumene hydroperoxide, t-butyl hydroperoxide and hydroxyl and superoxide radicals on GPX, SOD and catalase. For GPX, a 50% inactivation was observed at 10−1 M (30 min, 37°C) for hydrogen peroxide, 3 × 10−4 M (15 min, 37°C) for cumene hydroperoxide and 5 × 10−5 M (11 min, 37°C) for t-butyl hydroperoxide. Unlike the hydroxyl radicals, superoxide anions did not inactivate this enzyme. Catalase was inactivated by hydroxyl radicals and by superoxide anions but organic peroxides had no effect. SOD was inactivated by 50% by hydrogen peroxide at 4 × 10−4 M (20 min, 37°C), but organic peroxides and hydroxyl radicals were ineffective on this enzyme. Since the three enzymes of the antioxidant system are susceptible to at least one of the oxidative reactive molecules, in the case of high oxidative stresses such an inhibition could take place, leading to an irreverisble autocatalytical process in which the production rate of the oxidants will continuously increase, leading to cell death.

References (41)

  • K.J.A. Davies

    Protein damage and degradation by oxygen radiclas

  • A.J. Davison et al.

    Mechanism of the inhibition of catalase by ascorbate: roles of active oxygen species, copper and semidehydroascorbate

    J. Biol. Chem.

    (1986)
  • Y. Kono et al.

    Superoxide radical inhibits catalase

    J. Biol. Chem.

    (1982)
  • K.J.A. Davies

    Protein damage and degradation by oxygen radicals

  • K.J.A. Davies

    Protein damage and degradation by oxygen radicals

  • K.J.A. Davies

    Protein damage and degradation by oxygen radicals

  • S. Orrenius

    Roles and functions of glutathione

  • B. Halliwell et al.
  • H. Sies
  • J.M. McCord et al.

    The biology and pathology of oxygen radicals

    Ann. Int. Med.

    (1978)
  • Cited by (0)

    ∗∗

    Fellow of the I.R.S.I.A.

    Research assistant of the F.N.R.S.

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