The Study Of Magnetic Field Regulating The Differentiation Of Neural Stem Cells

Neural stem cells have strong plasticity and can differentiate into neurons,astrocytes and oligodendrocytes,Neural stem cells play a very important role during embryogenesis and adult neurogenesis.They have been used as a primary stem cell source for neurodegenerative disease.But now neural stem cell therapy still meet so many challenges in clinic,such as the survival rate and neural differentiation rate of the transplanted neural stem cells are low,and how to let the neural stem cell differentiated directionally under complicated signal regulation.So how to effectively manipulate the behavior of the Neural stem cells is becoming one research focus.The differentiation of neural stem cells is affected by many factors of the microenvironment,such as chemical and physical factors,cell-cell interaction and the connection of extracellular matrix(ECM).Recently,magnetic field(MF)has attracted so much attention of many scientist.It was previously reported that magnetic field can modulate some signal pathway which are involved in the stem cell differentiation process to modulate differentiation rate of the stem cells.In this study,we use neural stem cells(NSCs)which are from the hippocampus tissue of fetal rat brain as experimental models.We use Superparamagnetic iron oxide(SPIO)as a magnetic medium to produce magnetic force under magnetic field,then we study how magnetic field regulate the differentiation of neural stem cells.In this study,we have four experimental groups,Ctrl,SPIO,MF and SPIO+MF.According to our study,when SPIO 200?g/m L,MF 65 m T,we found SPIO and MF did not induce cytotoxicicty on neural stem cells,and they can maintain the stemness and proliferation ability of neural stem cells,more importantly,with the magnetic medium SPIO,MF can promote the neuronal differentiation rate,and decrease number of the GFAP positive cells,and can direct the neurite outgrowth preferentially along the direction imposed by an external magnetic field.At the same time,it also can increase the length of neurites,number of primary dendrites and number of branch points.So our experimental results demonstrate that magnetic field can be used as a non-invasive way to maintain the stemness and proliferation ability of neural stem cells and increase the neuronal differentiation and let the neuron neurite outgrowth preferentially along the direction imposed by an external magnetic field.Our study can provide a good theoretical foundation for clinical neural stem cell therapy for neurodegenerative disease.And it also lays academic and experimental foundation for promoting neural differentiation of transplanted neural stem cell in clinic.