Ageing stem and progenitor cells: implications for rejuvenation of the central nervous system.

The growing burden of the rapidly ageing global population has reinvigorated interest in the science of ageing and rejuvenation. Among organ systems, rejuvenation of the central nervous system (CNS) is arguably the most complex and challenging of tasks owing, among other things, to its startling structural and functional complexity and its restricted capacity for repair. Thus, the prospect of meaningful rejuvenation of the CNS has seemed an impossible goal; however, advances in stem cell science are beginning to challenge this assumption. This Review outlines these advances with a focus on ageing and rejuvenation of key endogenous stem and progenitor cell compartments in the CNS. Insights gleaned from studies of model organisms, chiefly rodents, will be considered in parallel with human studies.