Spurring Neurogenesis in the Living Brain
Researchers here demonstrate a method of adjusting the pace at which nerve cells in the brain are created, and suggest that it might work on other cell types in the body: "Neural stem cells (NSCs) in the adult mammalian brain generate neurons and glia throughout life. However, the physiological role of adult neurogenesis and the use of NSCs for therapy are highly controversial. One factor hampering the study and manipulation of neurogenesis is that NSCs, like most adult somatic stem cells, are difficult to expand and their switch to differentiation is hard to control. In this study, we show that acute overexpression of the cdk4 (cyclin-dependent kinase 4)-cyclinD1 complex in the adult mouse hippocampus cell autonomously increases the expansion of neural stem and progenitor cells while inhibiting neurogenesis. Importantly, we developed a system that allows the temporal control of cdk4-cyclinD1 overexpression, which can be used to increase the number of neurons generated from the pool of manipulated precursor cells. Beside providing a proof of principle that expansion versus differentiation of somatic stem cells can be controlled in vivo, our study describes, to the best of our knowledge, the first acute and inducible temporal control of neurogenesis in the mammalian brain, which may be critical for identifying the role of adult neurogenesis, using NSCs for therapy, and, perhaps, extending our findings to other adult somatic stem cells."
This seems important, since it's hard to imagine how an organism whose stem cell pools are being depleted will stay viable and healthy.
Some of these cell pools decline sharply in aging animals. See -
"Age-Dependent Depletion of Human Skin-Derived Progenitor Cells"
http://onlinelibrary.wiley.com/doi/10.1002/stem.27/pdf
Hopefully, a therapy, similar to the one in the paper cited, will add a few decades to human life expectancy.