Research Paper Advance Articles

Figure 4. Arg-ii^-/- mice reveal reduced accumulation of centrally located nuclei in aging skeletal muscles. (A) Representative confocal immunofluorescence staining of DAPI (white) and WGA (red) for nuclei and skeletal muscle fiber sarcolemma, respectively, in the old soleus muscle from young and old wild type (wt) and arg-ii^-/- (ko) male mice. Scale bar: 50 µm. (B–E) The left graphics in each figure present the percentage of centrally nucleated fibers/total of fibers in the mm² area for both soleus and tibialis in male and female mice as indicated. The fold changes based on the ratio of old/young (dotted line: young as 1) measuring the aging-dependent increase in centrally nucleated fibers were presented in the right bar graph in each panel. Combined one-way ANOVA and unpaired t-test with Welch’s correction were applied. n = 4–7 mice per group. ^*p < 0.05, ^**p < 0.01, ^***p < 0.001 between the groups.