Neural stem cells and strategies for the regeneration of the central nervous system

The adult mammalian central nervous system (CNS), especially that of adult humans, is a representative example of organs that do not regenerate. However, increasing interest has focused on the development of innovative therapeutic methods that aim to regenerate damaged CNS tissue by taking advantage of recent advances in stem cell and neuroscience research. Normal CNS development is initiated by the induction of stem cells in the CNS, i.e., neural stem cells (NSCs). Thus, the introduction or mobilization of NSCs could be expected to lead to CNS regeneration by recapitulating normal CNS development, in terms of the activation of the endogenous regenerative capacity and cell transplantation therapy. These lines of research will, hopefully, contribute to a basic understanding of the nature of NSCs, which should in turn lead to feasible strategies for the development of ideal ‘‘stem cell therapies’’ for the treatment of damaged brain and spinal cord tissue.

• 1
  NSCs are defined as undifferentiated cells that can both self-renew and generate the three major cell types that constitute the CNS, i.e. neurons, astrocytes, and oligodendrocytes, a characteristic known as multipotency.
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  COUP-TF was found to play a crucial role in the temporal identity transition of NSCs. During ontogenic development, NSCs undergo a temporal identity transition from the neurogenic to the gliogenic stage.
• 3
  Transplantation of the gliogenic secondary neurospheres, but not of the neurogenic primary neurospheres, promoted axonal growth { including that of the 5-HT-positive raphe-spinal tract { remyelination, and angiogenesis, and resulted in significant locomotor functional recovery after SCI