title: Long-term stimulation of neural progenitor cell migration after cortical ischemia in mice.
abstract: OBJECTIVE
  Cortical ischemia induces neural progenitor cell migration toward the injury site; however, whether these cells are capable of maintaining the migratory response for a longer period after injury remains uncertain.
  
  
  METHODS
  We analyzed progenitor migration up to 1 year after induction of photothrombotic stroke to the mouse neocortex. Migrating progenitors identified as doublecortin positive cells (DCX+) were assessed using the immunohistochemistry and immunofluorescence. The thymidine analogues chlorodeoxyuridine and iododeoxyuridine were used to birth-date the progenitor cells.
  
  
  RESULTS
  In the striatum, we detected elevated numbers of DCX+ cells up to 6 weeks postlesion. In the corpus callosum and the peri-infarct cortex (Ctx), DCX+ cell numbers were increased up to 1 year. The orientation of the migrating progenitors was mostly aligned with the corpus callosum fiber tract at all time points; however, in the Ctx, they aligned parallel to the infarct border. The injured cortex continuously receives new progenitors up to 1 year after lesion. Cells born after lesion did not become mature neurons, although a portion of the migrating progenitors showed initial signs of differentiation into neurons.
  
  
  CONCLUSIONS
  Neural progenitors might have a role in brain plasticity after cortical stroke, especially considering the prolonged window of migratory responses of up to 1 year after stroke lesion.
authors: Center for Brain Repair and Rehabilitation, Institute for Neuroscience and Physiology, University of Gothenburg, and Sahlgrenska University Hospital, Box 432, S-40530 Gothenburg, Sweden.
authors: Ahmed M
authors: AM
authors: Osman
authors: Michelle J
authors: MJ
authors: Porritt
authors: Michael
authors: M
authors: Nilsson
authors: H Georg
authors: HG
authors: Kuhn
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism / Q000473:pathology*; D002465:Cell Movement / Q000502:physiology*; D003337:Corpus Callosum / Q000378:metabolism / Q000473:pathology*; D003342:Corpus Striatum / Q000378:metabolism / Q000473:pathology*; D000089662:Doublecortin Protein; D005260:Female; D051379:Mice; D058953:Neural Stem Cells / Q000378:metabolism / Q000473:pathology*; D055495:Neurogenesis / Q000502:physiology; D009474:Neurons / Q000378:metabolism / Q000473:pathology