In addition, apparent increases in Type-I fibers with aggregated fiber-type grouping, which is a typical characteristic of sarcopenia (Lexell and Downham, 1991; Saini et al., 2009; Kung et al., 2014), was evident in the histochemical ATPase staining in PLT muscles in old-aged rats (Figures 3C–F), whereas uniform distribution was observed in adult rats (Figure 3A). This evidence concerns the gene DNAH8 and sarcopenia.