title: Induction of phosphorylated-Stat3 following focal cerebral ischemia in mice.
abstract: It has been shown that Stat3 is induced following transient cerebral ischemia in rat. However there is no evidence that cerebral ischemia stimulates the expression of phosphorylated-Stat3 (p-Stat3), which can activate cytokine-mediated signal transduction from the membrane to the nucleus. In the present study, we investigated the changes in p-Stat3 expression following middle cerebral artery occlusion in mice. Western blot analysis revealed a significant increase in the p-Stat3 protein in the peripheral part of the ischemic area, starting from 6 h after ischemia. p-Stat3 immunoreactivity was detected only in neurons, but not in astrocytes or microglia, and p-Stat3-positive neurons were increased in number in the peripheral part of the ischemic area at 24 h after ischemia. Double staining with aTdT-mediated biotinylated UTP nick end labeling (TUNEL) kit and the p-Stat3 antibody indicated that p-Stat3-positive neurons were also TUNEL-positive. Subsequent immuno-electron microscopic observations showed that p-Stat3-positive neurons were at different stages of degeneration. The present findings suggest that the increased expression of p-Stat3 after cerebral ischemia could play a crucial role in ischemia-induced neuron death.
authors.affiliation: Department of Anatomy, Ehime University School of Medicine, Shigenobu, 791-0295, Ehime, Japan.
authors.forename: T C
authors.initials: TC
authors.lastname: Wen
authors.forename: H
authors.initials: H
authors.lastname: Peng
authors.forename: R
authors.initials: R
authors.lastname: Hata
authors.forename: J
authors.initials: J
authors.lastname: Desaki
authors.forename: M
authors.initials: M
authors.lastname: Sakanaka
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D016923:Cell Death / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D016207:Cytokines / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004195:Disease Models, Animal; D005786:Gene Expression Regulation / Q000502:physiology; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron; D009410:Nerve Degeneration / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D009457:Neuroglia / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D009474:Neurons / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D010766:Phosphorylation; D050796:STAT3 Transcription Factor; D015398:Signal Transduction / Q000502:physiology; D015534:Trans-Activators / Q000378:metabolism*
chemical_list: D016207:Cytokines; D004268:DNA-Binding Proteins; D050796:STAT3 Transcription Factor; C494087:Stat3 protein, mouse; D015534:Trans-Activators