Fig. 3
The toxicity of Aβ42 oligomers is reduced by trodusquemine. a Effects of trodusquemine on the Aβ42 oligomer-induced decrease of MTT reduction. Oligomers (1 µM) were incubated in the absence or presence of 10:1–1:1 ratios of Aβ42-to-trodusquemine (blue bars) for 1 h at 37 °C and incubated with cells for 24 h. Cells were also treated with corresponding concentrations of pre-incubated trodusquemine (white bars), or pre-treated with 1 µM trodusquemine, washed and exposed to oligomers under the same conditions (red bar). Samples containing oligomers were analyzed by one-way ANOVA followed by Bonferroni’s multiple comparison test relative to untreated cells (***P < 0.001) and cells treated with oligomers (open circles, °°P < 0.01, °°°P < 0.001). A total of 80,000–100,000 cells were analyzed per condition in total. b Effects of trodusquemine on Aβ42 oligomer-induced ROS production. Oligomers (1 µM) were incubated with cells for 15 min in the absence or presence of 1 µM trodusquemine. Cells were also treated with 1 µM trodusquemine. The green fluorescence arises from the CM-H2DCFDA probe. The corresponding semi-quantitative values of the green fluorescence signals are shown. The red bar indicates the conditions shown in a. Scale bars, 30 µm. Samples containing oligomers were analyzed by one-way ANOVA followed by Bonferroni’s multiple comparison test relative to untreated cells (*P < 0.05, **P < 0.01, ***P < 0.001) and cells treated with oligomers (°°°P < 0.001). A total of 100–120 cells were analyzed per condition in total. c Representative confocal scanning microscopy images of the apical sections of cells treated for 15 min with oligomers (1 µM) in the absence or presence of 1 µM trodusquemine. Red and green fluorescence indicate the cell membranes and the oligomers, respectively. The histogram shows the percentage of co-localization. The red bar indicates the conditions shown in a. Scale bars, 10 µm. Samples containing oligomers were analyzed by one-way ANOVA followed by Bonferroni’s multiple comparison test relative to untreated cells (*P < 0.05, ***P < 0.001) and cells treated with oligomers (°°°P < 0.001). A total of 50–60 cells were analyzed per condition in total. In all panels, data represent mean ± s.e.m. of three independent experiments
