SIRT1 and myalgic encephalomeyelitis/chronic fatigue syndrome: Although these findings also suggest that ED might be a trait observed in a subset (~ 40–60%) of ME/CFS patients, further studies focused on evaluating both endothelial function in vivo and this set of Sirt1/eNOS-related miRs in plasma from the same cohort might be of great value to support this assumption, offering a more sensitive approach to detect ED earlier.