GluR6-FasL-Trx2 mediates denitrosylation and activation of procaspase-3 in cerebral ischemia/reperfusion in rats.
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.
Jiangsu Key Laboratory of Anesthesiology, Xuzhou Medical College, Jiangsu 221004, China.
N
N
Sun
J R
JR
Hao
X Y
XY
Li
X H
XH
Yin
Y Y
YY
Zong
G Y
GY
Zhang
C
C
Gao
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002545:Brain Ischemia / Q000150:complications / Q000201:enzymology* / Q000473:pathology; D053148:Caspase 3 / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D053222:Fas Ligand Protein / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D005947:Glucose / Q000172:deficiency; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D009474:Neurons / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D018696:Neuroprotective Agents / Q000494:pharmacology; D015538:Nitrosation / Q000187:drug effects; D010100:Oxygen / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018092:Kainic Acid Receptors / Q000378:metabolism*; D015427:Reperfusion Injury / Q000150:complications / Q000201:enzymology* / Q000473:pathology; D015398:Signal Transduction / Q000187:drug effects; D054481:Thioredoxin Reductase 1 / Q000378:metabolism; D013879:Thioredoxins / Q000378:metabolism*; D000097806:GluK2 Kainate Receptor
D053148:Caspase 3; D053222:Fas Ligand Protein; D005947:Glucose; D048031:JNK Mitogen-Activated Protein Kinases; D018696:Neuroprotective Agents; D010100:Oxygen; D018092:Kainic Acid Receptors; D054481:Thioredoxin Reductase 1; D013879:Thioredoxins; D000097806:GluK2 Kainate Receptor; C505662:Faslg protein, rat; C516113:Txn2 protein, rat; C505410:Casp3 protein, rat