Figure 7.

FOXO3a knockdown cells display intolerance to H₂O₂ challenge and TR4 can rescue cell growth. A, Expression of FOXO3a and TR4 mRNA in FOXO3a-scramble 1, FOXO3a-siRNA 3, and FOXO3a-siRNA 3+TR4 C2C12 cells. *, P < 0.05 (ANOVA) as compared with the other two groups. B, Cells (1 × 10³) of three C2C12 clones were seeded into 96-well dishes for 24 h and then untreated or treated with 250 μm H₂O₂ for 2 h. Dimetylthiazol-diphenyltetra-zoliumbromide (MTT) assay was performed at 0, 1, 2, 3, and 4 d after H₂O₂ treatment. Relative cell growth rates are presented as fold induction (means ± sd) relative to that of untreated cells on the same day set as 1, from three independent experiments. The relative cell growth rates at the same day were compared. *, P < 0.05 (ANOVA) when comparing FOXO3a-siRNA3 C2C12 cells with FOXO3a-siRNA3+TR4 cells at d 3 and 4. #, P < 0.05 (ANOVA) when comparing FOXO3a-scramble1 C2C12 cells with FOXO3a-siRNA3 cells at d 2, 3, and 4.