APP and Alzheimer disease: Moreover, the NF-M-positive fluorescence signal was significantly decreased in the APP group compared with that in the GFP group (74.6 ± 3.4% vs. 100%, n = 3, P < 0.01), while Ost (88.0 ± 4.9%) treatment increased NF-M expression (n = 3, P < 0.01, Figure 4C), further confirming that Ost stimulated NSCs differentiation into neurons in an AD cell model.