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 (P<0.05). Western blotting results revealed that there were no statistical differences in Akt phosphorylation levels between NGF group and NGF-PEG-PLGA-NPs group (P>0.05), but the phosphorylation levels of Akt were both higher than other four groups (P<0.05). There were also no significant differences between LY294002+NGF and LY294002+NGF-PEG-PLGA-NPs groups and control group (P>0.05), 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.