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

Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15219, USA.
FEBS letters (Impact Factor: 3.34). 10/2009; 583(21):3437-42. DOI: 10.1016/j.febslet.2009.10.013
Source: PubMed

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.

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