In vitro effects of H 2 O 2 on neural stem cell differentiation.

The development of the CNS is a complex and well-regulated process, where stem cells differentiate into committed cells depending on the stimuli from the microenvironment. Alterations of oxygen levels were stated to be significant in terms of brain development and neurogenesis during embryonic development, as well as the adult neurogenesis. As a product of oxygen processing, hydrogen peroxide (H 2 O 2 ) has been established as a key regulator, acting as a secondary messenger, of signal transduction and cellular biological functions. H 2 O 2 is involved in survival, proliferation, and differentiation of neural stem cells into committed cells of the CNS. Effects of different concentrations of exogenous H 2 O 2 on neuronal differentiation and the molecular pathways involved are yet to be clearly understood. Here, we investigated the concentration-dependent effects of H 2 O 2 on differentiation of neural stem cells using CGR8 embryonic mouse stem cell line. We have demonstrated that treated doses of H 2 O 2 suppress neural differentiation; additionally, our study suggests that relatively high doses of exogenous H 2 O 2 suppress the differentiation process of neural stem cells through AKT and p38 pathways.