Fig. 1: FoxO3 activation decreases upon heart injury in postnatal heart.

Apical resection was performed at postnatal mice at p1, followed by sample collection at 1 dpr and 5 dpr, respectively. a, b Representative images (a) and quantification (b) of western blotting for FoxO3 expression and its phosphorylation in postnatal heart at 1 dpr (n = 3 hearts per group). (c, d Representative images (c) and quantification (d) of western blotting for FoxO3 expression and its phosphorylation in postnatal heart at 5 dpr (n = 4 hearts for sham and 3 hearts for 5 dpr). e–g Representative images (e) and quantification of FoxO3 fluorescent intensity (f, ~400 cells in 4 hearts per group) and FoxO3-positive cells (g, n = 4 hearts per group) in apical zone at 5 dpr. h–j Representative images (h) and quantification of FoxO3 fluorescent intensity (i, n = ~400 cells per group) and FoxO3-positive cells (j, n = 4 hearts per group) in remote zone at 5 dpr. k Western blotting validation of FoxO3 in primary cardiomyocytes isolated from hearts at 5 dpr (n = 3 per group). l Representative images (left) and quantification (right) of western blotting for Akt expression and its phosphorylation in postnatal heart at 5 dpr (n = 3 hearts per group). All data are presented as the mean ± SEM. P values are from two-tailed t test. ns, no significant difference. Source data are provided as a Source data file.