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Inactivation of cytosolic aldehyde dehydrogenase via S-nitrosylation in ethanol-exposed rat liver.

ABSTRACT: Aldehyde dehydrogenase (ALDH) isozymes are critically important in the metabolism of acetaldehyde, thus preventing its accumulation after ethanol-exposure. We previously reported that mitochondrial ALDH2 could be inactivated via S-nitrosylation in ethanol-exposed rats. This study was aimed at investigating whether cytosolic ALDH1, with a relatively-low-Km value (11-18 microM) for acetaldehyde, could be also inhibited in ethanol-exposed rats. Chronic or binge ethanol-exposure significantly decreased ALDH1 activity, which was restored by addition of dithiothreitol. Immunoblot analysis with the anti-S-nitroso-Cys antibody showed one immunoreactive band in the immunoprecipitated ALDH1 only from ethanol-exposed rats, but not from pair-fed controls, suggesting S-nitrosylation of ALDH1. Therefore inactivation of ALDH1 via S-nitrosylation can result in accumulation of acetaldehyde upon ethanol-exposure.

SUBMITTER: Moon KH

PROVIDER: S-EPMC2693367 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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Inactivation of cytosolic aldehyde dehydrogenase via S-nitrosylation in ethanol-exposed rat liver.

Moon Kwan-Hoon KH Abdelmegeed Mohamed A MA Song Byoung-Joon BJ

FEBS letters 20070725 21

Aldehyde dehydrogenase (ALDH) isozymes are critically important in the metabolism of acetaldehyde, thus preventing its accumulation after ethanol-exposure. We previously reported that mitochondrial ALDH2 could be inactivated via S-nitrosylation in ethanol-exposed rats. This study was aimed at investigating whether cytosolic ALDH1, with a relatively-low-Km value (11-18 microM) for acetaldehyde, could be also inhibited in ethanol-exposed rats. Chronic or binge ethanol-exposure significantly decrea ...[more]

PMID: 17673211

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