Tyrosine nitration of voltage-dependent anion channels in cardiac ischemia-reperfusion: reduction by peroxynitrite scavenging.
Biochim Biophys Acta
; 1817(11): 2049-59, 2012 Nov.
Article
em En
| MEDLINE
| ID: mdl-22709907
ABSTRACT
Excess superoxide (O(2)(-)) and nitric oxide (NO) forms peroxynitrite (ONOO(-)) during cardiac ischemia reperfusion (IR) injury, which in turn induces protein tyrosine nitration (tyr-N). Mitochondria are both a source of and target for ONOO(-). Our aim was to identify specific mitochondrial proteins that display enhanced tyr-N after cardiac IR injury, and to explore whether inhibiting O(2)(-)/ONOO(-) during IR decreases mitochondrial protein tyr-N and consequently improves cardiac function. We show here that IR increased tyr-N of 35 and 15kDa mitochondrial proteins using Western blot analysis with 3-nitrotyrosine antibody. Immunoprecipitation (IP) followed by LC-MS/MS identified 13 protein candidates for tyr-N. IP and Western blot identified and confirmed that the 35kDa tyr-N protein is the voltage-dependent anion channel (VDAC). Tyr-N of native cardiac VDAC with IR was verified on recombinant (r) VDAC with exogenous ONOO(-). We also found that ONOO(-) directly enhanced rVDAC channel activity, and rVDAC tyr-N induced by ONOO(-) formed oligomers. Resveratrol (RES), a scavenger of O(2)(-)/ONOO(-), reduced the tyr-N levels of both native and recombinant VDAC, while L-NAME, which inhibits NO generation, only reduced tyr-N levels of native VDAC. O(2)(-) and ONOO(-) levels were reduced in perfused hearts during IR by RES and L-NAME and this was accompanied by improved cardiac function. These results identify tyr-N of VDAC and show that reducing ONOO(-) during cardiac IR injury can attenuate tyr-N of VDAC and improve cardiac function.
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Base de dados:
MEDLINE
Assunto principal:
Tirosina
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Traumatismo por Reperfusão Miocárdica
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Ácido Peroxinitroso
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Proteínas Mitocondriais
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Canais de Ânion Dependentes de Voltagem
Limite:
Animals
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article