FIGURE 3.

Early chronic administration of RS 67333 reduces Aβ₄₀ and Aβ₄₂ levels in 5XFAD mice. 5XFAD female (3 or 4 months at termination) mice were treated chronically with 1 mg/kg RS 67333 twice a week according to protocol 1 (A,B), protocol 2 (C,D) or protocol 3 (E,F). Total Aβ₄₀ and Aβ₄₂species were quantified in the insoluble (A,C,E) and soluble (B,D,F) brain fractions. Data are the mean ± SEM. ^*p < 0.05, ^**p < 0.01, ^***p < 0.001 compared with vehicle (unpaired Student’s t test). The mean levels (nanogram per milligram total protein ± SEM, n = 5/group) in the three vehicle-treated groups (protocol 1, 2, and 3, respectively) were: insoluble Aβ₄₀: 483 ± 13, 346 ± 62, and 187 ± 31; insoluble Aβ₄₂: 2006 ± 38; 2190 ± 265, and 1477 ± 322; soluble Aβ₄₀: 7.62 ± 1.52, 3.97 ± 0.81, and 10.75 ± 0.87; soluble Aβ₄₂: 0.44 ± 0.07, 0.82 ± 0.02, and 2.48 ± 0.59.