FNDC5 and diabetes mellitus: Based on recently reported results in mice (26), we speculate that replacement with recombinant irisin in young DM patients might improve their functional and metabolic profile; these prospective view is also sustained by in vitro data showing that irisin stimulates myogenesis, as suggested by increased myocyte cell proliferation, higher myogenin/MYOG mRNA levels together with lower transcripts of myostatin/MSTN and dystrophin/DMD, and the muscle atrophy-related factors MuRF1 and MAFbx (5, 46).