For in vitro studies in primary hippocampal neurons, all experiments were repeated 3 to 5 times. The spine density was compared by one-way ANOVA with Tukey’s post-hoc test when compared between-genotypes and different treatment. The unpaired t-test was used as compared the two treatments within the same genotype of neurons. For the in vivo studies, values for each APP−/− animal and their APP+/− counterparts were obtained by taking the average of the data from all neurons for each animal. An independent sample t-test was performed on spine density, spine percentage, spine volume, and dendritic length. Sholl analysis data were compared by repeated measures ANOVA with Bonferroni post-hoc test with genotype (APP−/− vs. APP+/−) as the between-group factor and distance from the soma as the repeated-measures factor (Dickstein et al., 2010; Radley et al., 2008). The α level was set at 0.05 for all analyses in the study, and all data were represented as mean ± SEM. All statistical analyses were carried out using Prism software (GraphPad Software, Inc, La Jolla, CA, USA).
