Typical and atypical stem cells in the brain, vitamin C effect and neuropathology

Stem cells are considered a valuable cellular resource for tissue replacement therapies in most brain disorders. Stem cells have the ability to self-replicate and differentiate into numerous cell types, including neurons, oligodendrocytes and astrocytes. As a result, stem cells have been considered the "holy grail" of modern medical neuroscience. Despite their tremendous therapeutic potential, little is known about the mechanisms that regulate their differentiation. In this review, we analyze stem cells in embryonic and adult brains, and illustrate the differentiation pathways that give origin to most brain cells. We also evaluate the emergent role of the well known anti-oxidant, vitamin C, in stem cell differentiation. We believe that a complete understanding of all molecular players, including vitamin C, in stem cell differentiation will positively impact on the use of stem cell transplantation for neurodegenerative diseases.

THE ESTABLISHMENT OF MODEL FOR PRIMARY CULTURED TANYCYTES / 解剖学报

Objective Tanycytes(TAs) is a specialized eppendymal glia that locates mostly in the ventral lateral wall of the ventricle III and median eminence(ME).Due to its peculiar location and directly exposure to the cerebrospinal fluid,blood,neuroendocrine hormones and neurons,tanycytes play an important role in the brain barrier system,brain-CSF neurohumoral circuit and immune-neuroendocrine network.They maintain immature characters during the adulthood and have naturally conducted the neuroregeneration process in the adult hypothalamus of mammal animals.This research was designed to identify tanycytes(TAs) in postnatal 7 days of Wistar rats and then establish the cell model of TAs for further study.Methods Tanycytes of postnatal 7 days of Wistar rats were identified by the immunohistochemical technology using glial fibrillary acidic protein(GFAP) and vimentin(VIM),which are the intermediate filament markers of glia cells.The qualitative analysis was performed by the NADPH-d stain of nitric oxide sythenase(NOS).Primary TAs model was established by the cell culture technique and identified by the same methods as in vivo.Results Primary cultured TAs expressed VIM,GFAP and NOS which was identical with those in vivo.Conclusion Cell model of TAs from postnatal 7days of Wistar rats in vitro has been established and TAs could be used as a proper substrate for transplanting.