Tronco

Cell Prolif. 2008, 41 (Suppl. 1), 94–114

D. C. XXXX ORIGINAL XXX UK C. V Journal The Authors © 2007 compilation © 2007 0960-7722 & ARTICLES Cell HessPublishing Ltd Blackwell Publishing Ltd, Cell Proliferation, 41 (Suppl. 1), xx–xx. CPRProliferation . Borlongan Oxford, Blackwell

Stem cells and neurological diseases
D. C. Hess* and C. V. Borlongan* ,†

*Department of Neurology, Medical College of Georgia, and †Medical Research Service, VA Medical Center, Augusta, GA 30912, USA Received 14 February 2007; revision accepted 11 April 2007

Abstract. Cells of the central nervous system were once thought to be incapable of regeneration. This dogma has been challenged in the last decade with studies showing new, migrating stem cells in the brain in many rodent injury models and findings of new neurones in the human hippocampus in adults. Moreover, there are reports of bone marrow-derived cells developing neuronal and vascular phenotypes and aiding in repair of injured brain. These findings have fuelled excitement and interest in regenerative medicine for neurological diseases, arguably the most difficult diseases to treat. There are numerous proposed regenerative approaches to neurological diseases. These include cell therapy approaches in which cells are delivered intracerebrally or are infused by an intravenous or intra-arterial route; stem cell mobilization approaches in which endogenous stem and progenitor cells are mobilized by cytokines such as granulocyte colony stimulatory factor (GCSF) or chemokines such as SDF-1; trophic and growth factor support, such as delivering brain-derived neurotrophic factor (BDNF) or glialderived neurotrophic factor (GDNF) into the brain to support injured neurones; these approaches may be used together to maximize recovery. While initially, it was thought that cell therapy might work by a ‘cell replacement’ mechanism, a large body of evidence is emerging that cell therapy works by providing trophic or ‘chaperone’ support to the