Interaction of reactive oxygen and nitrogen species with albumin- and methemoglobin-bound dinitrosyl-iron complexes.
Nitric Oxide
; 18(1): 37-46, 2008 Feb.
Article
em En
| MEDLINE
| ID: mdl-18036856
ABSTRACT
Destructive effect of superoxide anions O2- derived from KO(2) or xanthine-xanthine oxidase system on dinitrosyl-iron complexes bound with bovine albumin or methemoglobin (DNIC-BSA or DNIC-MetHb) was demonstrated. The sensitivity of DNIC-BSA synthesized by the addition of DNIC with cysteine, thiosulfate or phosphate (DNIC-BSA-1, DNIC-BSA-2 or DNIC-BSA-3, respectively) to destructive action of O2- decreased in row DNIC-BSA-1>DNIC-BSA-3>DNIC-BSA-2. The estimated rate constant for the reaction between O2- and DNIC-BSA-3 was equal to approximately 10(7)M(-1)s(-1). However, hydrogen peroxide and tert-butyl hydrogenperoxide (t-BOOH) did not induce any noticeable degradation of DNIC-BSA-3 even when used at concentrations exceeding by one order of magnitude those of the complex. As to their action on DNIC-MetHb both hydrogen peroxide and t-BOOH-induced rapid degradation of the complex. Both agents could induce the process due to the effect of alkylperoxyl or protein-derived free radicals formed at the interaction of the agents with ferri-heme groups of MetHb. Peroxynitrite (ONOO(-)) could also initiate protein-bound DNIC degradation more efficiently in the reaction with DNIC-BSA-3. Higher resistance of DNIC-MetHb to peroxynitrite was most probably due to the protective action of heme groups on ONOO(-). However, the analysis allows to suggest that the interaction of protein-bound DNICs with O2- is the only factor responsible for the degradation of the complexes in cells and tissues.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Metemoglobina
/
Soroalbumina Bovina
/
Espécies Reativas de Oxigênio
/
Espécies Reativas de Nitrogênio
/
Ferro
/
Óxidos de Nitrogênio
Limite:
Animals
Idioma:
En
Revista:
Nitric Oxide
Assunto da revista:
BIOQUIMICA
/
QUIMICA
Ano de publicação:
2008
Tipo de documento:
Article