Regulation of skeletal myogenesis in C2C12 cells through modulation of Pax7, MyoD, and myogenin via different low-frequency electromagnetic field energies.

Abstract

BACKGROUND: A low-frequency electromagnetic field (LF-EMF) exerts important biological effects on the human body.OBJECTIVE: We previously studied the immunity and atrophy of gastrocnemius muscles in rats with spinal cord injuries and found that LF-EMF with a magnetic flux density of 1.5 mT exerted excellent therapeutic and preventive effects on reducing myotubes and increasing spatium intermusculare. However, the effects of LF-EMF on all stages of skeletal myogenesis, such as activation, proliferation, differentiation, and fusion of satellite cells to myotubes as stimulated by myogenic regulatoryfactors (MRFs), have not been fully elucidated.METHODS: This study investigated the optimal LF-EMF magnetic flux density that exerted maximal effects on all stages of C2C12 cell skeletal myogenesis as well as its impact on regulatory MRF.RESULTS: The results showed that an LF-EMF with a magnetic flux density of 2.0 mT could activate C2C12 cells and upregulate the proliferation-promoting transcription factor PAX7. On the other hand, 1.5 mT EMF could upregulate the expression of MyoD and myogenin.CONCLUSION: LF-EMF could prevent the disappearance of myotubes, with different magnetic flux densities of LF-EMF exerting independent and positive effects on skeletal myogenesis such as satellite cell activation and proliferation, muscle cell differentiation, and myocyte fusion.