Figure 5.

LPS increases Aβ42 levels in E4FAD+ mice. (a) In the cortex, there were no changes in soluble (left panel) or total Aβ42 levels (center panel) when assessed biochemically. Total Aβ is the sum of the amount of Aβ in every fraction divided by the protein content in every fraction. As total Aβ primarily consists of extracellular Aβ, quantitative IHC analysis was conducted (right panel and images). There were higher levels of Aβ in the cortex of LPS-treated E4FAD+ mice compared to LPS- and PBS-treated E3FAD+ mice. (b) In the hippocampus, there were higher levels of soluble Aβ (PBS extraction) in the hippocampus of LPS-treated E4FAD+ mice compared to all other groups. Although no differences were observed for total Aβ42, when extracellular Aβ in the subiculum was quantified by IHC, there were higher levels in LPS-treated E4FAD+ mice compared to E3FAD+ mice treated with LPS. (c) For apoE, the only significant differences were in the soluble (PBS) extracts with lower apoE levels in E4FAD− mice treated with PBS compared to E3FAD− mice treated with PBS. However, there were no effects of LPS treatment on apoE levels compared to PBS controls for any groups. Data are expressed as the mean ± SEM. (a, b) *p < .05 by two-way ANOVA followed by Bonferroni post hoc analysis (c, d) *p < .05 by three-way ANOVA followed by Bonferroni post hoc analysis comparing all groups.