Figure 4. Macrophages accumulating in dystrophic muscles have increased expression of senescence markers. (A) SA-β-Gal staining of gastrocnemius muscle sections from 1, 4, and 8 week old dKO mice with quantification. Significant changes in SA-β-Gal staining was observed by 8 weeks. (B) Immunofluorescent staining of gastrocnemius muscle sections from 8-week old dKO mice indicating co-localization of the senescence marker C12FDG and CD68. ~26% of CD68+ cells are C12FDG+. (C) Immunofluorescent staining of muscle sections from 8 week old dKO mice indicating co-localization of the senescence marker p21 and RhoA. ~78% of RhoA+ cells are p21+. n=6 for 1-week and 4-week old mice, and n=8 for 8-week old mice. * indicates p<0.05.