Fig. 5: Trifluoperazine suppresses the PI3K-Akt-S6K1 signaling cascade but does not affect histone acetylation in hippocampal neurons.

a–c Hippocampal neurons cultured from WT mice were treated with vorinostat (20 μM) (a), trichostatin A (20 μM) (b), and trifluoperazine (20 μM) (c) for 1 h, and then harvested for Western blot analysis. Level of the acetylated histone H3 and H4 (Ac-H3 and Ac-H4) in vehicle-treated and drug-treated sample was normalized to total H3 and H4, respectively. d PI3 kinase activity in lysates from primary WT hippocampal neurons treated with 20 µM trifluoperazine (TFP) or vehicle was determined by ELISA, which measures the concentration of PIP3 converted from PIP2. e, f Primary WT hippocampal neurons were treated with trifluoperazine (TFP) (20 µM) or LY-294002 (20 µM) for 1 h. Samples harvested immediately after drug or vehicle treatment were analyzed by Western blot for the level of pAkt (normalized to total Akt) (e) and pS6K1 (normalized to total S6K1) (f). The relative protein level in the vehicle-treated control group was defined as 1 (a–c, e, f). The p values (a–d) were determined by student’s t-test. The p value between the treated and control samples (e, f) was determined by one-way ANOVA and post hoc Tukey’s test (e, f).