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Radioprotection by short-term oxidative preconditioning: role of manganese superoxide dismutase.

ABSTRACT: Manganese superoxide dismutase (MnSOD) is vital to the protection of mitochondria and cells against oxidative stress. Earlier, we demonstrated that catalytically active homo-tetramer of MnSOD can be stabilized by oxidative cross-linking. Here we report that this effect may be translated into increased radioresistance of mouse embryonic cells (MECs) by pre-exposure to oxidative stress. Pre-treatment of MECs with antimycin A, rotenone or H(2)O(2) increased their survival after irradiation. Using MnSOD siRNA, we show that MECs with decreased MnSOD levels displayed a lowered ability to preconditioning. Thus oxidative preconditioning may be used for targeted regulation of MnSOD.

SUBMITTER: Belikova NA

PROVIDER: S-EPMC2784259 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Radioprotection by short-term oxidative preconditioning: role of manganese superoxide dismutase.

Belikova Natalia A NA Glumac Ashley A Rafikov Ruslan R Jiang Jianfei J Greenberger Joel S JS Kagan Valerian E VE Bayir Hülya H

FEBS letters 20091012 21

Manganese superoxide dismutase (MnSOD) is vital to the protection of mitochondria and cells against oxidative stress. Earlier, we demonstrated that catalytically active homo-tetramer of MnSOD can be stabilized by oxidative cross-linking. Here we report that this effect may be translated into increased radioresistance of mouse embryonic cells (MECs) by pre-exposure to oxidative stress. Pre-treatment of MECs with antimycin A, rotenone or H(2)O(2) increased their survival after irradiation. Using M ...[more]

PMID: 19822147

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