title: Hypoxia-ischemia induces thioredoxin expression and nitrotyrosine formation in new-born rat brain.
abstract: Thioredoxin (TRX) is a 13 kDa protein with antioxidant effect and redox regulating functions. Peroxynitrite is a strong oxidizing and nitrating agent which can react with all classes of biomolecules. In the present study, we focused on the association between TRX and nitrotyrosine, which served as a marker of peroxynitrite formation, in the neonatal hypoxia-ischemia (HI) rat brain. At 4-16 h after HI, the immunoreactivity for TRX was diminished in the injured region in the cortex and striatum, whereas nitrotyrosine immunoreactivity was enhanced. In contrast, around the injured region, TRX immunoreactivity was enhanced in survival neurons at 4-24 h after HI, while the immunoreactivity for nitrotyrosine was mostly not detected. Northern blot analysis showed increased TRX mRNA induction in the cerebral hemisphere ipsilateral to the carotid ligation from 4-24 h after HI but not in the contralateral hypoxic hemisphere. These findings suggest that production of peroxynitrite is involved in HI brain injury, and that induced TRX plays a neuroprotective role against oxidative stress resulting from HI.
authors.affiliation: Department of Neurosurgery, Kyoto University Graduate School of Medicine, Sakyo, Kyoto, Japan.
authors.forename: Itaro
authors.initials: I
authors.lastname: Hattori
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Takagi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nozaki
authors.forename: Norihiko
authors.initials: N
authors.lastname: Kondo
authors.forename: Jie
authors.initials: J
authors.lastname: Bai
authors.forename: Hajime
authors.initials: H
authors.lastname: Nakamura
authors.forename: Nobuo
authors.initials: N
authors.lastname: Hashimoto
authors.forename: Junji
authors.initials: J
authors.lastname: Yodoi
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D015152:Blotting, Northern; D001921:Brain / Q000378:metabolism / Q000473:pathology*; D000860:Hypoxia; D008953:Models, Anatomic; D016877:Oxidants / Q000494:pharmacology; D030421:Peroxynitrous Acid / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury; D013879:Thioredoxins / Q000096:biosynthesis*; D013997:Time Factors; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000378:metabolism
chemical_list: D016877:Oxidants; D012333:RNA, Messenger; D030421:Peroxynitrous Acid; C002744:3-nitrotyrosine; D014443:Tyrosine; D013879:Thioredoxins