By investigating satellite cells obtained from the murine tibialis anterior muscle of young and old mice, Sahu et al. [212] demonstrated that in old injured muscles the expression of the aging suppressor gene Klotho, whose deficiency is involved in the onset of sarcopenia, is prevented due to the loss of the demethylation of its promoter (which normally occurs in young injured muscles), suggesting that the epigenetic control of Klotho is lost with aging, thus hampering muscle regeneration. Here, KL is linked to sarcopenia.