OR2H2 regulates the differentiation of human myoblast cells by its ligand aldehyde 13-13

Olfactory receptors (ORs) regulate various cellular processes in the human body. The receptors' participation in physiological and pathophysiological processes could be demonstrated in several studies. In addition to the regulation of sperm motility, respiratory physiology, and heart contraction, ORs play a crucial role in cancer cells. In murine myoblasts, mOR23 regulates the myogenesis and branching of skeletal muscle cells. To date, the expression and physiological role of ORs in human skeletal muscle cells have not been thoroughly elucidated. We demonstrate that four different ORs are expressed at the transcript level in differentiated myoblasts, and one other OR is expressed in undifferentiated myoblasts. Moreover, we characterized the expression of OR2H2 in differentiated human myoblasts and identified a specific ligand, aldehyde 13-13. We could observe a concentration-dependent Ca2+ increase in differentiated human myoblasts upon aldehyde 13-13 stimulation, which is mediated by PI3K signaling. Aldehyde 13-13 has a reducing effect on myoblast fusion. We conclude that OR2H2 could have a regulatory role in myoblast differentiation. To the best of our knowledge, this report presents the first verification of the expression of ORs in human myoblasts. OR2H2 might be an interesting candidate for playing a role in the complex mechanism of myogenesis.