Interaction of Oxoferrylmyoglobin and Dinitrosyl-Iron Complexes

K. B. Shumaev^1*, N. E. Petrova², I. V. Zabbarova¹, A. F. Vanin³, A. F. Topunov², V. Z. Lankin², and E. K. Ruuge¹

¹Russian Cardiology Research Center, 3-ya Cherepkovskaya ul. 15A, Moscow 121552, Russia; fax: (095) 415-2962; E-mail: shumaev@vipmail.ru

²Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia; fax: (7-095) 954-2732; E-mail: inbio@inbio.ras.ru

³Semenov Institute of Chemical Physics, Russian Academy of Sciences, ul. Kosygina 4, Moscow 117977, Russia; fax: (7-095) 938-5621; E-mail: mikoyan@center.chph.ras.ru

^* To whom correspondence should be addressed.

Received November 21, 2003

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It is shown that dinitrosyl-iron complexes (DNIC) with glutathione can reduce oxoferrylmyoglobin forming on interaction of tert-butyl hydroperoxide and metmyoglobin. A rapid decrease in the DNIC concentration was observed under the conditions of production of tert-butyl free radicals; however, destruction of DNIC in the presence of oxoferrylmyoglobin alone was negligible. It is demonstrated that DNIC reduces oxoferrylmyoglobin more than an order more efficiently than S-nitrosoglutathione and glutathione. DNIC also inhibits formation of the thiyl radicals of glutathione in a medium containing metmyoglobin and tert-butyl hydroperoxide. A mechanism of the antioxidant action of DNIC based on regeneration of the nitrosyl complexes from the products of their interaction with oxoferrylheme is proposed.

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KEY WORDS: nitric oxide, dinitrosyl-iron complexes, oxoferrylmyoglobin, free radicals, hydroperoxides

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