APP and amyloidosis: Under this condition, Mn treatment (100 μM for 24 h) significantly increased BACE1 by 103.84 ± 16.42% (n = 5) and PS1 by 37.75 ± 5.33% (n = 5; p < 0.05), and reduced ADAM10 by 22.77 ± 6.20% (p < 0.05, two-way ANOVA), respectively, in APPsw-N2a cells (Figures 5A–D); APP, C99, and Aβ were also increased by 51.89 ± 17.27% (n = 5), 48.21 ± 8.28% (n = 5) and 210.26 ± 27.14% (n = 5), respectively (p < 0.05), while the non-amyloidosis-processing product C83 was decreased by 35.40 ± 12.52% (n = 5; p < 0.05, two-way ANOVA; Figures 5E–I).