Pulsed magnetic field promotes proliferation and neurotrophic genes expression in Schwann cells in vitro

As one of the most classic supportive cells, Schwann cells (SCs) have been considered as potential candidates for nerve regeneration. However, SCs cultured in vitro are found with attenuated biological activities, which limits their application. Pulsed magnetic field (PMF) has been demonstrated to be safe and efficient to regulate several cells activities. However, it is still unclear the effect of PMF on proliferation and expression of neurotrophic factors in SCs. Therefore, the present study was designed to examine such possible effects. The tolerance of SCs to PMF was examined by flow cytometry and scanning electron microscopy (SEM). The proliferation of cells was detected by an EdU labeling assay and a Prestoblue assay. The expression and secretion of neurotrophic factors in SCs was assayed by RT-PCR and ELISA. We found that 2.0 mT was the optimal intensity that caused relatively little apoptosis with profound proliferation in SCs. The gene expression and protein level of brain-derived neurotrophic factor (BDNF), glial cell derived neurotrophic factor (GDNF), vascular endothelial growth factor (VEGF) were up-regulated following PMF stimulation, additionally, the gene expression and protein level of neurotrophin-3 (NT-3) was not enhanced by PMF. Our results suggested that PMF could improve SC proliferation and biological function, which might shed a light on the potential utilization of PMF in nerve regeneration via SC activation.