Neurogenesis from Endogenous Neural Stem Cells After Stroke: A Future Therapeutic Target to Promote Functional Restoration?
Recent experimental evidence obtained mainly in rodents has indicated that the stroke-damaged adult brain makes an attempt to repair itself by producing new neurons from its own neural stem cells. Here, we summarize the current status of this research with an emphasis on how, in the future, optimization of this potential self-repair mechanism could become of therapeutical value to promote functional restoration after stroke. Currently, our knowledge about the mechanisms regulating the different steps of neurogenesis after stroke is incomplete. Despite a lot of circumstantial evidence, we also do not know if stroke-induced neurogenesis contributes to functional improvement and to what extent the new neurons are integrated into existing neural circuitries. It is highly likely that, in order to have a substantial impact on the recovery after stroke, neurogenesis has to be markedly enhanced. Based on available data, this should primarily be achieved by increasing the survival and differentiation of the generated neuroblasts. Moreover, for maximum functional recovery, optimization of neurogenesis most likely needs to be combined with stimulation of other endogenous neuroregenerative responses, e.g., protection and sprouting of remaining mature neurons, and transplantation of stem cell-derived neurons and glia cells.
KeywordsNeural Stem Cell Middle Cerebral Artery Occlusion Mature Neuron Functional Restoration Neuroblast Migration
Our own research was supported by the Swedish Research Council, Juvenile Diabetes Research Foundation, EU project LSHB-2006-037526 (StemStroke), and the Söderberg, Crafoord, Segerfalk, and Kock Foundations. The Lund Stem Cell Center is supported by a Center of Excellence grant in Life Sciences from the Swedish Foundation for Strategic Research.
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