SCM-198 improved cognitive performances of Aβ
-injected Sprague-Dawley (SD) rats in the Morris water maze (MWM) test, alleviated microglial activation, suppressed phosphorylation of extracellular signal-regulated kinase (ERK) and tau, inhibited NF-κB p65 translocation and synaptophysin loss in vivo . SD rats were subjected to bilateral microinjections of 2 μg/μl aggregated Aβ1-40 (5 μl/side) or vehicle into hippocampus and MWM test was conducted 12 days after surgery. (a) Mean escape latency from Day 1 to Day 3; (b) time spent in target quadrant. Data represent mean ± SEM of nine to ten rats per group. *P < 0.05, **P < 0.01, Tukey’s test versus only Aβ1-40-treated group; #P < 0.05, ##P < 0.01, ###P < 0.001, Tukey’s test versus sham group. Phosphorylation of ERK (p-ERK) (c, d), nuclear p65 (NF-κB-p65) (c, e), phosphorylation of tau (p-tau) (c, f) and synaptophysin loss (c, g) were analyzed by Western blot (n = 5 rats/group). (i) Examples of iba-1 staining for microglia (dark brown, indicated by arrows) in hippocampus (scale bar, 100 μM; n = 3 rats/group). (h) Integrated optical density (IOD) for of iba-1 staining for microglia. Data represent mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001, Tukey’s test versus only Aβ1-40-treated group; #P < 0.05, ##P < 0.01, Tukey’s test versus sham group.