New insights into mechanisms of gamma-diketone-induced axonopathy

Neurochem Res. 2009 Nov;34(11):1919-23. doi: 10.1007/s11064-009-9977-9. Epub 2009 Apr 29.

Abstract

We analyzed the impact of axonopathy-inducing agents 1,2-diacetylbenzene (1,2-DAB) and 2,5-hexanedione (2,5-HD) on membrane-bound protein disulfide isomerase (mPDI) versus soluble PDI (sPDI), or PDI-family member thioredoxin (THX), and asked whether changes in PDI/THX were associated with production of oxidative/nitrosative species in the Sprague-Dawley rat. We show that 1,2-DAB and 2,5-HD lower the abundance of sPDI and THX. However, the protein expression of mPDI is increased in 1,2-DAB axonopathy and neuroproteins became more S-nitrosylated. The abundance of heme oxygenase-1 (HO-1) and isoforms of nitric oxide synthase (neuronal, endothelial, and inducible NOS) remained unchanged suggesting that S-nitrosylation occured via increased mPDI-transnitrosylation and/or diminished THX-denitrosylation. The transcription of PDI and glucose regulated protein-78 (GRP-78) remained unchanged indicating that post-translational modifications, e.g. S-nitrosylation, mediate the pathogenesis of gamma-diketone axonopathy. These findings open opportunities for new therapeutic testing (e.g., supplementation with denitrosylating THX) in gamma-diketone-induced axonal disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetophenones*
  • Animals
  • Axons / pathology*
  • Cell Membrane / metabolism
  • Endoplasmic Reticulum Chaperone BiP
  • Heat-Shock Proteins / genetics
  • Heat-Shock Proteins / metabolism
  • Heme Oxygenase-1 / metabolism
  • Hexanones*
  • Isoenzymes / metabolism
  • Male
  • Nerve Tissue Proteins / metabolism
  • Nitric Oxide Synthase / metabolism
  • Nitroso Compounds / metabolism
  • Protein Binding
  • Protein Disulfide-Isomerases / genetics
  • Protein Disulfide-Isomerases / metabolism
  • Protein Processing, Post-Translational
  • Rats
  • Rats, Sprague-Dawley
  • Reactive Nitrogen Species / metabolism
  • Reactive Oxygen Species / metabolism
  • Spinal Cord Diseases / chemically induced
  • Spinal Cord Diseases / metabolism
  • Spinal Cord Diseases / pathology*
  • Thioredoxins / metabolism
  • Transcription, Genetic

Substances

  • Acetophenones
  • Endoplasmic Reticulum Chaperone BiP
  • Heat-Shock Proteins
  • Hexanones
  • Isoenzymes
  • Nerve Tissue Proteins
  • Nitroso Compounds
  • Reactive Nitrogen Species
  • Reactive Oxygen Species
  • Thioredoxins
  • 1,2-diacetylbenzene
  • 2,5-hexanedione
  • Nitric Oxide Synthase
  • Heme Oxygenase-1
  • Protein Disulfide-Isomerases