RESUMO
BACKGROUND:Our previous studies confirmed that NGF-PEG-PLGA-NPs has good sustained release effect and biological activity in vitro, and can induce the differentiation of PC12 cel s into neuron-like cel s. OBJECTIVE:To investigate the feasibility of neuronal differentiation of neural stem cel s from septal area of fetal brain induced by NGF-PEG-PLGA-NPs and its influence on PI3K/Akt signaling pathway. METHODS:According to optimization prescription, NGF-PEG-PLGA-NPs were prepared by multiple emulsion solvent diffusion method. Neural stem cel s were induced to neuronal differentiation in six groups, including control group, NGF group, NGF-PEG-PLGA-NPs group, LY294002 group, LY294002+NGF group and LY294002+NGF-PEG-PLGA-NPs group. Neurons were identified by immunofluorescence, while phosphorylation levels of Akt in PI3K/Akt signaling pathway were detected by western blotting. RESULTS AND CONCLUSION:The proportions ofβ-Tubulin III-positive neurons in control group, NGF group, NGF-PEG-PLGA-NPs group, LY294002 group, LY294002+NGF group and LY294002+NGF-PEG-PLGA-NPs group were (22.80±2.58)%, (35.80±3.98)%, (35.40±5.77)%, (26.60±3.87)%, (21.20±2.59)%and (25.80±7.22)%, respectively. There were no statistical differences in neuronal differentiation between NGF group and NGF-PEG-PLGA-NPs group (P>0.05), but the ratios of neural differentiation in the two groups were both higher than that in the other four groups (P0.05), but the phosphorylation levels of Akt were both higher than other four groups (P0.05), but the phosphorylation levels of Akt were higher than LY294002 group (P<0.05). Results suggest that NGF-PEG-PLGA-NPs promoted neural differentiation of neural stem cel s. The role might be related to increasing phosphorylation levels of Akt in PI3K/Akt signaling pathway.