Figure 3.

Inhibitory effects of HPB242 on accumulation of Aβ_1-42in the brain of Tg2576 mice. Aβ accumulation in the brains of Tg2576 mice was determined by immunohistochemical analysis using Aβ_1-42-specific antibody (A). The sections of Tg2576 mouse brains were incubated with anti-Aβ_1-42 primary antibody, and biotinylated secondary antibody. Immunoperoxidase staining of brains of Tg2576 and treated-Tg2576 mice shown (brown color). Aβ_1-42 level was measured in mouse brains by ELISA as described in Materials and Methods (B). The value is mean ± standard error of the mean (SEM) (n = 8 mice). The activity of β-secretase was investigated using assay kit as described (C). Values measured from each group of mice were calibrated by the amount of protein and expressed as mean ± SEM (n = 8 mice). The expression of APP and BACE1 were detected by western blotting using specific antibodies in the mouse brain. Each blot is representative of three experiments (D). *Significantly different from non-treated Tg2576 mice (P < 0.05).