title: Appearance of neural stem cells around the damaged area following traumatic brain injury in aged rats.
abstract: We have previously reported free radical production after traumatic brain injury (TBI), which induces neural stem cell (NSC) degeneration and death. However, the effects of aging on NSC proliferation around the damaged area following TBI have not been investigated. Therefore, in this study, we used 10-week (young group) and 24-month-old (aged group) rat TBI models to investigate the effects of aging on NSC proliferation around damaged tissue using immunohistochemical and ex vivo techniques. Young and aged rats received TBI. At 1, 3 and 7 days after TBI, immunohistochemical and lipid peroxidation studies were performed. Immunohistochemistry revealed that the number of nestin-positive cells around the damaged area after TBI in the aged group decreased significantly when compared with those in the young group (P < 0.01). However, the number of 8-hydroxy-2'-deoxyguanosine-, 4-hydroxy-2-nonenal- and single-stranded DNA (ssDNA)-positive cells and the level of peroxidation around the damaged area after TBI significantly increased in the aged group, compared with those in the young group (P < 0.01). Furthermore, almost all ssDNA-positive cells in young and aged groups co-localized with NeuN and nestin staining. Ex vivo studies revealed that neurospheres, which differentiated into neurons and glia in culture, could only be isolated from injured brain tissue in young and aged groups at 3 days after TBI. These results indicate that, although there were fewer NSCs that have the potential to differentiate into neurons and glia, these NSCs escaped free radical-induced degeneration around the damaged area after TBI in the aged rat brain.
authors.affiliation: Department of Pathology, Faculty of Medicine, Kinki University, 377-2, Ohno-higashi, Osakasayama, Osaka, 589-8511, Japan. tatsuki@med.kindai.ac.jp
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Itoh
authors.forename: Motohiro
authors.initials: M
authors.lastname: Imano
authors.forename: Shozo
authors.initials: S
authors.lastname: Nishida
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tsubaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakayama
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Mizuguchi
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Yamanaka
authors.forename: Masaki
authors.initials: M
authors.lastname: Tabuchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Munakata
authors.forename: Shigeo
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Akihiko
authors.initials: A
authors.lastname: Ito
authors.forename: Takao
authors.initials: T
authors.lastname: Satou
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000375:Aging; D000447:Aldehydes / Q000032:analysis; D000818:Animals; D001930:Brain Injuries / Q000378:metabolism* / Q000473:pathology*; D002454:Cell Differentiation / Q000502:physiology; D004277:DNA, Single-Stranded / Q000032:analysis; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000032:analysis / Q000096:biosynthesis; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000032:analysis / Q000096:biosynthesis; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000096:biosynthesis; D064231:Nestin; D058953:Neural Stem Cells / Q000166:cytology* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000447:Aldehydes; D004277:DNA, Single-Stranded; D007381:Intermediate Filament Proteins; D009419:Nerve Tissue Proteins; C577486:Nes protein, rat; D064231:Nestin; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine; C027576:4-hydroxy-2-nonenal