Irisin produced by muscles during exercise and promoting fat burning also exhibits geroprotective effect and induces telomere elongation in normal somatic cells. Special attention is paid to studies of the role of peptides Lys-Glu, Glu-Asp-Arg, and Ala-Glu-Asp-Gly in epigenetic regulation of irisin content. The data suggest that the immunomodulatory peptide Lys-Glu and neuroprotective peptide Glu-Asp-Arg modulate the life span by modulating irisin gene expression.