miR-9 stimulation enhances the differentiation of neural stem cells with zoanthamine by regulating Notch signaling

The protective effect of zoanthamine on Alzheimer's disease by enhancing differentiation of neural stem cells (NSCs) was evaluated. NSCs were isolated from C57BL/6 mice and assessed by cell viability and apoptosis assays. The cells were separated into five different groups: green fluorescent protein (GFP; transfected with GFP), amyloid precursor protein (APP; transfected with APP), APP + zoanthamine, APP + miR-9 inhibitor, and APP + miR-9 inhibitor + zoanthamine. The effects of zoanthamine on the differentiation of NSCs was determined. Moreover, the effects of zoanthamine on the expression of miR-9 and Notch signalling pathway members was assessed by western blot analysis and reverse-transcription polymerase chain reaction. There was a significant increase in cell viability and a decrease in apoptosis of NSCs in the APP + zoanthamine group compared with the APP group. Treatment with zoanthamine attenuated miR-9 expression and neuronal cell differentiation in APP-treated NSCs. Moreover, in the APP + miR-9 inhibitor group, neuronal cell differentiation and miR-9 expression were significantly reduced, and treatment with zoanthamine reduced the number of differentiated cells and miR-9 expression compared with the APP + miR-9 inhibitor group. There was a significant reduction in the expression of Hes1 and NICD proteins in the APP + zoanthamine group relative to the APP group. In addition, the levels of Hes1 and NICD were enhanced by inhibition of miR-9 but zoanthamine prevented these increases. In conclusion, these results suggest that treatment with zoanthamine enhances the differentiation of NSCs by regulating Notch signalling via elevated miR-9 expression.