Cellular signaling in neural stem cells: implications for restorative neurosurgery.
Over the course of the past few decades, it has become apparent that in contrast to previously held beliefs, the adult central nervous system (CNS) may have the capability of regeneration and repair. This greatly expands the possibilities for the future treatment of CNS disorders, with the potential strategies of treatment targeting the entire scope of neurological diseases. Indeed, there is now ample evidence that stem cells exist in the CNS throughout life, and the progeny of these stem cells may have the ability to assume the functional role of neural cells that have been lost. The existence of stem cells is no longer in dispute. In addition, once transplanted, stem cells have been shown to survive, migrate, and differentiate. Nevertheless, the clinical utility of stem cell therapy for neurorestoration remains elusive. Without question, the control of the behavior of stem cells for therapeutic advantage poses considerable challenges. In this paper, the authors discuss the cellular signaling processes that influence the behavior of stem cells. These signaling processes take place in the microenvironment of the stem cell known as the niche. Also considered are the implications attending the replication and manipulation of elements of the stem cell niche to restore function in the CNS by using stem cell therapy.