Fig. 3

Small molecule compounds inhibit apoE4-catalyzed Aβ pathology in primary neurons from 5xFAD transgenic mice. a Schematic of drug efficacy experiments using primary neurons from the 5xFAD transgenic mouse model of Alzheimer’s disease. One week after cell isolation from day P1-P2 pups, cells were exposed to 100 nM Aβ42 and 1 nM apoE4 and were treated concurrently with 0.01, 0.1, or 1.0 μM compound in a final concentration of 0.5% (v/v) DMSO. The cell medium was changed every 3 days by removing half and replacing it with a fresh medium containing Aβ42, apoE4, and compound such that the starting concentrations were maintained for the duration of the experiment. At 9 dpe, cells were fixed for immunocytochemistry (ICC) and the conditioned medium was collected for analysis of Aβ concentrations by enzyme-linked immunosorbent assay (ELISA). b Representative ICC images of neurons at 9 dpe labeled for total tau (red), Aβ (white), and cell nuclei (blue). Scale bars = 20 μm. c Percent positive area of Hoechst⁺ cell nuclei at 9 dpe, relative to the DPBS control group. The data represent the mean ± SD of n = 6 wells per group. *P < 0.05 by one-way ANOVA. d Percent positive area of Aβ⁺ pathology at 9 dpe, relative to the DPBS control group. The data represent the mean ± SD of n = 6 wells per group. ***P < 0.001 by one-way ANOVA. e Representative ICC images of neurons at 9 dpe to apoE4 and Aβ42 and treated with compounds at 1 μM and labeled for total tau (red), Aβ (white), and cell nuclei (blue). Scale bars = 20 μm. f Percent positive area of Hoechst⁺ cell nuclei at 9 dpe, relative to the DMSO control group. The data represent the mean ± SD of n = 6 wells for DMSO and n = 3 wells per concentration for compounds. *P < 0.05, **P < 0.01, and ***P < 0.001 compared to the DMSO control by one-way ANOVA. g Percent positive area of Aβ⁺ pathology at 9 dpe, relative to the DMSO control group. The data represent the mean ± SD of n = 6 wells for DMSO and n = 3 wells per concentration for compounds. *P < 0.05, **P < 0.01, and ***P < 0.001 compared to the DMSO control by one-way ANOVA