Skeletal muscle has the impressive capacity to completely regenerate even after relatively severe injuries in young individuals, but this process is dysregulated in multiple cell types in the microenvironment in numerous diseases and aging. In this issue of the JCI, Cao et al., using an elegant set of genetic mouse models and pharmacological approaches, demonstrated that gasdermin E (GSDME) was required in myeloid cells after sterile muscle injury to normally regenerate muscle and that downstream IL-18 release prevented intramuscular ectopic fat deposition. GSDME expression was reduced in human muscles from aged individuals, and Gsdme was increased after muscle injury in young, but not old, mice. The ability of IL-18 to partially improve regeneration in aged GSDME-knockout mice demonstrates the potential clinical relevance of this finding in dysregulated muscle regeneration associated with aging.
Krishna et al. (Tue,) studied this question.