Thioredoxin restores nitric oxide-induced inhibition of protein kinase C activity in lung endothelial cells.

摘要: We previously reported that exposure to exogenous nitric oxide (NO) causes diminished expression of thioredoxin/thioredoxin reductase, a critical component the redox system regulates functions redox-sensitive enzymes, receptors, and transcription factors. Here we examined role thioredoxin in NO-induced inhibition protein kinase C (PKC) isoform(s) potential interaction PKC pulmonary artery endothelial cells (PAEC) culture. Exposure NO gas (8 ppm) significantly catalytic activity representative isoforms conventional, novel, atypical PKCs α,e, ζ, respectively, PAEC. Further examination NO's effect on PKC-ζ revealed was time-dependent regulated by posttranscriptional mechanism. loss restored incubation with disulfide reducing agent dithiothreitol (DTT) as well purified or reductase. Confocal imaging studies co-localization These results indicate that: (1) is associated S-nitrosylation-mediated formation active site thiols DTT and/or enzyme restore (2) oxidation endogenous reduced reductase are required reduce