A new function of a previously isolated compound that stimulates activation and differentiation of myogenic precursor cells leading to efficient myofiber regeneration and muscle repair.

Muscle repair following severe injury is slow and incomplete due to the limited regenerative capacity of muscles comprising the function. In this study, one pure compound structurally corresponding to triterpenoid, which can directly induce the activation, proliferation and maturation of quiescent satellite cells into myocytes in vitro, was isolated from Geum japonicum. The potential effect of this compound on myogenesis was further tested in repair of severe muscle injury. It was found that this compound could significantly stimulate the regenerative potential of the damaged muscle resulting in regeneration of myotubes and myotube bundles time-dependently replacing the damaged muscle tissues. This compound-mediated active regeneration of new myofibers repairing damaged muscles was probably due to its direct action on activation and proliferation of quiescent myogenic precursor cells and enhancement of their maturation into regenerating myotubes, as was demonstrated in our primary myogenic precursor cells culture experiments. The up-regulated expression of endogenous phospho-Akt1 in compound-treated myogenic precursor cells may also contribute to the process of myofiber regeneration and muscle repair probably via promoting myogenic cell survival capacity.