title: Evidence for the involvement of Par-4 in ischemic neuron cell death.
abstract: After a stroke many neurons in the ischemic brain tissue die by a process called apoptosis, a form of cell death that may be preventable. The specific molecular cascades that mediate ischemic neuronal death are not well understood. The authors recently identified prostate apoptosis response-4 (Par-4) as a protein that participates in the death of cultured hippocampal neurons induced by trophic factor withdrawal and exposure to glutamate. Here, the authors show that Par-4 levels increase in vulnerable populations of hippocampal and striatal neurons in rats after transient forebrain ischemia; Par-4 levels increased within 6 hours of reperfusion and remained elevated in neurons undergoing apoptosis 3 days later. After transient focal ischemia in mice, Par-4 levels were increased 6 to 12 hours after reperfusion in the infarcted cortex and the striatum, and activation of caspase-8 occurred with a similar time course. Par-4 immunoreactivity was localized predominantly in cortical neurons at the border of the infarct area. A Par-4 antisense oligonucleotide protected cultured hippocampal neurons against apoptosis induced by chemical hypoxia and significantly reduced focal ischemic damage in mice. The current data suggest that early up-regulation of Par-4 plays a pivotal role in ischemic neuronal death in animal models of stroke and cardiac arrest.
authors.affiliation: Laboratory of Neurosciences, National Institute on Aging, Baltimore, Maryland 21224, USA.
authors.forename: C
authors.initials: C
authors.lastname: Culmsee
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.forename: J
authors.initials: J
authors.lastname: Krieglstein
authors.forename: M P
authors.initials: MP
authors.lastname: Mattson
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D003342:Corpus Striatum / Q000166:cytology; D006624:Hippocampus / Q000166:cytology; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D002546:Ischemic Attack, Transient / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000166:cytology* / Q000201:enzymology; D020319:Oligodeoxyribonucleotides, Antisense / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000378:metabolism; D020521:Stroke / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D020319:Oligodeoxyribonucleotides, Antisense; C101296:prostate apoptosis response-4 protein; D020169:Caspases