Extended Data Fig. 2.

The age-related increase of lipofuscin in skeletal muscle (SkM). Representative images of Sudan Black B (SBB) staining (a) and quantification of the numbers of positive foci per quadriceps section (b) from young and old female mice (n = 4 per age group). Two-tailed unpaired t test was used; error bars represent the standard error of the mean. * and ** denote p < 0.05 and 0.01 respectively.