Fig. 7. Hippocampal amyloidosis and tau phosphorylation remain unaltered in treated 5×FAD mice.

(A) Analysis of APP expression level in the hippocampus by using immunoblotting. Unpaired Student’s t test. n = 4 per group. The right panel shows representative images of immunoblotting. β-Actin was used as the loading control. (B) Aβ deposition in the hippocampal region was measured and analyzed by immunostaining using Aβ antibody. Unpaired Student’s t test. 5×FAD saline mice, n = 6 and 5×FAD MK0677/SKF81297 mice, n = 5. The right panel shows representative images of Aβ staining (red). The neurons were identified by the staining of NeuN (green). (C) Soluble Aβ40 and Aβ42 amounts in hippocampal homogenate were detected by ELISA assay. Unpaired Student’s t test. 5×FAD saline mice, n = 6 and 5×FAD MK0677/SKF81297 mice, n = 5. (D) Analysis of intracellular Aβ in hippocampal CA1 neurons. Unpaired Student’s t test. 5×FAD saline mice, n = 8 and 5×FAD MK0677/SKF81297 mice, n = 5. The right panel shows representative images. Aβ was recognized by anti-Aβ antibody (red). Neurons were labeled by anti–β-III-tubulin (green). Nuclei were identified by the staining of DAPI (blue color). The overlaid staining of Aβ and β-III-tubulin indicates intraneuronal Aβ. Scale bar, 20 μm. (E) Congo red staining was used to label extracellular parenchymal Aβ plaques. Unpaired Student’s t test. 5×FAD saline mice, n = 8 and 5×FAD MK0677/SKF81297 mice, n = 5. The right panel shows representative images of Aβ plaque staining. (F) Immunoblotting analysis of tau phosphorylation at different motifs and total tau in mouse hippocampal tissues. Unpaired Student’s t test. n = 4 per group. The lower panel shows representative images of immunoblotting. β-Actin was used as the loading control. P-tau stands for phosphorylated tau, and T-tau stands for total tau.