Fasudil Stimulates Neurite Outgrowth and Promotes Differentiation in C17.2 Neural Stem Cells by Modulating Notch Signalling but not Autophagy.

BACKGROUND Neurite outgrowth is one of the important therapeutic strategies for neuronal plasticity and regeneration in neural disorders. Fasudil is a clinical medication that is used to treat subarachnoid haemorrhage (SAH) and that is beneficial for many animal models of central nervous system (CNS) diseases. In this study, we hypothesised that fasudil administration would promote neurite outgrowth in neural stem cells (NSCs). METHODS Changes in cell morphology were imaged under a light microscope, and neurite-bearing cells were counted. Cell viability and the necrosis rate were determined by MTT and LDH assays, respectively. Additionally, western blot and immunofluorescence analyses were performed to detect protein expression levels. RESULTS We found that fasudil promoted neurite outgrowth in C17.2 cells in a time- and dose-dependent manner. The neurite-bearing C17.2 cells were differentiated by detecting the changes in neural and astrocytic markers after fasudil treatment through down-regulating Notch signalling. Previously, fasudil was reported to induce autophagy, which plays an important role in neural differentiation. However, both rapamycin, an autophagy inducer, and 3-methyl-adenine (3-MA), an autophagy inhibitor, had no effects on the fasudil-induced neurite outgrowth, suggesting that autophagy may be not involved in this process. CONCLUSION In summary, fasudil could stimulate neurite outgrowth and differentiation in C17.2 cells by modulating Notch signalling but not autophagy.