Renalase Peptide (RP220) Activates MAPK Signaling Pathways in Primary Mouse Skeletal Muscle Cells.

Renalase is a secreted protein that was initially discovered in the kidney and that is also expressed in skeletal muscle. Moreover, renalase peptide RP220 activates MAPK signaling in the kidneys. This study investigated the effects of the RP220 on skeletal muscle using primary cultured cells. Notably, RP220 treatment did not alter the myogenic differentiation phenotype; however, intracellular signaling analyses revealed significant phosphorylation of p38 and ERK, which are MAPK family members. These results indicate that renalase affects MAPK signaling, but its physiological or developmental effects on skeletal muscle are not yet known.