Figure 2.
FOXO3 Is Required for SCs to Self-Renew during Muscle Regeneration
(A) Four weeks after the initiation of tamoxifen treatment, Foxo3cKO and control mice were injured, and muscles were harvested 7 days later. In the panels, the arrows point to PAX7+ve SCs associated with CNFs in control and Foxo3cKO muscles. The graph shows the average number of PAX7+ve SCs per 100 CNFs from multiple sections in control and Foxo3cKO muscles (n = 4 mice per genotype) (∗∗p < 0.01).
(B) One month after tamoxifen treatment, Foxo3cKO-YFP and control-YFP mice were injured, and muscles were harvested 1 month later. Cryosections were stained for Laminin and YFP. In the panels, the arrows point to YFP+ve SCs associated with CNFs in control and Foxo3cKO muscles. The insets show high-magnification images of the areas in dotted rectangles. The graph shows the average number of YFP+ve SCs per 100 CNFs from multiple sections in control and Foxo3cKO muscles (n = 4 mice per genotype) (∗∗p < 0.05).
(C) Muscles of tamoxifen-treated Foxo3cKO and control mice were injured twice, with a spacing of 2 weeks between successive injuries. Cryosections stained with hematoxylin and eosin reveal impaired regeneration in the Foxo3cKO muscles. The graph shows the mean cross-sectional area of CNFs from multiple sections in control and Foxo3cKO muscles (n = 3 mice per genotype) (∗∗p < 0.05).