Expression levels of FIS1 also decrease in old age (Picca et al., 2017), and older animals have lower levels of FIS1 and autophagy than younger animals, resulting in impaired autophagy in older muscles (Joseph et al., 2013), while knockdown of FIS1 activates muscle atrophy in sarcopenia (Calvani et al., 2013). This evidence concerns the gene FIS1 and sarcopenia.