Document Type

Article

Language

eng

Format of Original

11 p.; 25 cm

Publication Date

11-2012

Publisher

Elsevier

Source Publication

Biochimica et Biophysica Acta: Bioenergetics

Source ISSN

0005-2728

Original Item ID

doi: 10.1016/j.bbabio.2012.06.004; PubMed Central, PMCID: PMC3985433

Abstract

Excess superoxide (O2) 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 O2/ONOO during IR decreases mitochondrial protein tyr-N and consequently improves cardiac function. We show here that IR increased tyr-N of 35 and 15 kDa 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 35 kDa 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 O2/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. O2 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.

Comments

NOTICE: this is the author’s version of a work that was accepted for publication in Biochimica et Biophysica Acta: Bioenergetics. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Biochimica et Biophysica Acta: Bioenergetics, Vol. 1817, No. 11 (November 2012): 2049-2059. DOI. © Elsevier 2012. Used with permission.

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