CERS1 and sarcopenia: Due to our consistent observation of increased very long chain C24:0 /C24:1 ceramides and dihydroceramides upon Cers1/CERS1 inhibition, we suggest a molecular network in which the compensatory upregulation of CERS2 derived very long chain ceramide and dihydroceramide species in aging might accelerate age-related muscle wasting and dysfunction, hence contributing to sarcopenia (Figure 5F).