Fig. 4: Protein phosphatase 2a (Ppp2ca) functioned as an upstream regulator for aging- and stress-induced changes of AMPK-p47phox.
From: Aging increases vulnerability to stress-induced depression via upregulation of NADPH oxidase in mice
a Expression levels of phosphatases (Ppp2ca and Ppm1e) and kinases (Lkb1, Tak1, and Camkk2) in HT22 cells treated with GC (400 ng/ml) for 24 h (n = 8, each). b Ppp2ca transcript levels in HT22 cells treated with GC for 2, 6, or 24 h, GC (for 24 h) plus RU486, and RU486 alone (n = 8, each; GC2h vs. GC6h vs. GC24h, One-way ANOVA, F(3,28)=26.77, p < 0.0001; GC + RU486, Two-way ANOVA, GC, F(1,28)=77.75, p < 0.0001; RU486, F(1,28)=49.79, p < 0.0001; GC x RU486, F(1,28)=20.04, p = 0.0001). c ChIP assay data showing GR binding levels to the Ppp2ca promoter in HT22 cells treated with for 24 h (n = 8, each). Red boxes, GRE. d Western blot data showing p-AMPK levels in HT22 cells treated with siPpp2ca and siCON (n = 5, each). e A summary of the signaling pathway of PP2A, p-AMPK, and p47phox. f Ppp2ca transcript levels in the hippocampus of mice at the indicated age (n = 6, each; One-way ANOVA, F(3,20)=5.697, p = 0.0055). g Experimental design. Mice were treated with RST14d, and then received siPpp2ca or siCON injection in CA3 region (red arrows) on post-stress day 1, and were placed on the behavioral tests on post-stress day 3. Arrow, tissue prep point. h Ppp2ca transcript levels in the CA3 of mice treated with RST14d and siPpp2ca or siCON injection (n = 8, each; One-way ANOVA, F(2,21)=52.76, p < 0.0001). i Representative tracking plots and time spent in the target and non-target fields in the sociability test (n = 5 mice/group; target field, One-way ANOVA, F(2,12)=5.973, p = 0.0173; non-target field, One-way ANOVA, F(2,12)=5.77, p = 0.0175). j, k Immobility time in the TST and FST for mice treated with RST14d and injected with siPpp2ca or siCON (n = 5 mice/group; TST, One-way ANOVA, F(2,12)=4.616, p = 0.0326; FST, One-way ANOVA, F(2,12)=6.817, p = 0.0105). l p47phox and gp91phox transcript levels in the CA3 of mice treated with RST14d and siPpp2ca or siCON injection (n = 6, each; p47phox, One-way ANOVA, F(2,15)=9.357, p = 0.0023; gp91phox, One-way ANOVA, F(2,15)=34.95, p < 0.0001). *p < 0.05 and **p < 0.01. One-way ANOVA followed by a Newman–Keuls post hoc test and two-way ANOVA followed by a Bonferroni post hoc test.
