Joint action of VEGF and bFGF on differentiation of neural stem cells from embryonic rat cortex

Objective To investigate the joint action of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) on differentiation of neural stem cells (NSCs) isolated from cortex of rats embryos.Methods The SD rats pregnant for 14 days were selected,and the NSCs of cortex of rat embryos were isolated and cultured in serum-free medium.The third generation cells were treated with VEGF (200μg/L) and/or bFGF (20μg/L),and the cells of control group were cultured with neither VEGF nor bFGF.The expressions of nestin (neuroectodermal marker),β-tubulin-Ⅲ (neuron marker) and glial fibrillary acidic protein (GFAP,astrocyte marker) in NSCs were determined by immunocytochemistry 7 days after cultivation.Results The primarily cultured NSCs isolated from embryonic rat cortex grew in a floating state in vitro and formed compact cell masses,and the passage cells could form new cell masses.Most of the primary cells and passage cells expressed nestin.Some differentiated cells expressed β-tubulin-Ⅲ while some others expressed GFAP.Compared with the control group,VEGF and/or bFGF could elevate the proportion of differentiation of NSCs to neurons.The proportion of β-tubulin-Ⅲ positive cells (80.3%) was the highest,while the proportion of GFAP positive cells (18.6%) was the lowest in VEGF+bFGF group compared with those in other groups.The proportion of β-tubulin-Ⅲ positive cells (60.4%) and GFAP positive cells (38.5%) in bFGF group showed no significant difference compared with those in VEGF group (60.3% and 38.7%,respectively,P0.05).Conclusion Both VEGF and bFGF can promote the differentiation of NSCs to neurons,and they present a synergistic action.