Premium
Modulation of S‐nitrosation by thioredoxin regulates endothelial permeability
Author(s) -
Mujica Patricio E.,
González Francisco G.,
Durán Walter N.
Publication year - 2012
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.26.1_supplement.676.18
Subject(s) - enos , thioredoxin , cytosol , chemistry , nitrosation , microbiology and biotechnology , immunoprecipitation , thioredoxin reductase , nitric oxide , biochemistry , biology , oxidative stress , enzyme , nitric oxide synthase , organic chemistry , gene
Protein S‐nitrosation has emerged recently as a mechanism to regulate cell function. We tested the hypothesis that cytosolic thioredoxin (Trx1) – thioredoxin reductase (TrxR1) system contributes to the control of endothelial permeability. In human microvascular endothelial cells (HMVEC) of dermal origin, we used PAF‐stimulated hyperpermeability and hypoxia‐reoxygenation as test models. Inhibition of Trx1/TrxR1 elevated baseline permeability, and allowed further increase in permeability by PAF. PAF increased global S‐nitrosation as reported by anti Snitroso cysteine antibody. Double depletion of Trx1/TrxR1 increased baseline as well as PAF‐stimulated and hypoxia‐induced global S‐nitrosation. We observed, by immunofluorescence microscopy and immunoprecipitation, the association between Trx1 and eNOS. Both enzymes associate and colocalize in the cytosol suggesting that Trx1 contributes to regulation of eNOS activity. We conclude that interactions between eNOS and the Trx1/TrxR1 system contribute to activation and inactivation of hyperpermeability. (Supported by NIH 5RO1 HL070634 and 5RO1 HL088479).