GluR6-FasL-Trx2 mediates denitrosylation and activation of procaspase-3 in cerebral ischemia/reperfusion in rats

Cell Death Dis. 2013 Aug 15;4(8):e771. doi: 10.1038/cddis.2013.299.

Abstract

Global cerebral ischemia/reperfusion (I/R) facilitates the activation of procaspase-3 and promotes apoptosis in hippocampus. But the mechanisms have remained uncharacterized. Protein S-nitrosylation and denitrosylation is an important reversible posttranslational modification, which is a common mechanism in signal transduction and affects numerous physiological and pathophysiological events. However, it is not known whether S-nitrosylation/denitrosylation modification of procaspase-3 serves as a component of apoptosis and cell death induced by cerebral I/R. Here we show that procaspase-3 is significantly denitrosylated and activated after I/R in rat hippocampus. NS102, a glutamate receptor 6 (GluR6) antagonist, can inhibit the denitrosylation of procaspase-3 and diminish the increased Fas ligand (FasL) and thioredoxin (Trx)-2 expression induced by cerebral I/R. Moreover, downregulation of FasL expression by antisense oligodeoxynucleotides inhibits the denitrosylation and activation of procaspase-3. Auranofin, a TrxR inhibitor or TrxR2 antisense oligodeoxynucleotide, has similar effects. In primary hippocampal cultures, Lentiviral-mediated knockdown of FasL and TrxR2 before the oxygen and glucose deprivation/reoxygenation further verifies that FasL and TrxR2 are involved in the denitrosylation of procaspase-3. In situ TUNEL staining and cresyl violet staining validate that inhibiting denitrosylation of procaspase-3 may exert neuroprotective effect on apoptosis and cell death induced by cerebral I/R in hippocampal CA1 pyramidal neurons. This is the first evidence that cerebral I/R mediates procaspase-3 denitrosylation and activation through GluR6-FasL-Trx2 pathway, which leads to neuronal apoptosis and cell death.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Brain Ischemia / complications
  • Brain Ischemia / enzymology*
  • Brain Ischemia / pathology
  • Caspase 3 / metabolism*
  • Enzyme Activation / drug effects
  • Fas Ligand Protein / metabolism*
  • Gene Knockdown Techniques
  • GluK2 Kainate Receptor
  • Glucose / deficiency
  • Hippocampus / drug effects
  • Hippocampus / enzymology
  • Hippocampus / pathology
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Male
  • Models, Biological
  • Neurons / drug effects
  • Neurons / enzymology
  • Neurons / pathology
  • Neuroprotective Agents / pharmacology
  • Nitrosation / drug effects
  • Oxygen / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Kainic Acid / metabolism*
  • Reperfusion Injury / complications
  • Reperfusion Injury / enzymology*
  • Reperfusion Injury / pathology
  • Signal Transduction / drug effects
  • Thioredoxin Reductase 1 / metabolism
  • Thioredoxins / metabolism*

Substances

  • Fas Ligand Protein
  • Faslg protein, rat
  • Neuroprotective Agents
  • Receptors, Kainic Acid
  • Txn2 protein, rat
  • Thioredoxins
  • Thioredoxin Reductase 1
  • JNK Mitogen-Activated Protein Kinases
  • Casp3 protein, rat
  • Caspase 3
  • Glucose
  • Oxygen