Non-contact electrical stimulation as an effective means to promote wound healing

Electrical stimulation has been demonstrated to have beneficial effects in skin tissue repair. However, most electrical stimulations are applied with percutaneous electrode, which is prone to causing serious trauma. Using non-contact electrical stimulation (NCES) is expected to reduce the potential risk. In this study, NCES was expediently exerted by a self-designed practical device. Electrode plates of 10-cm spacing with appropriate side lengths of 21 and 30 cm were selected by EF distribution analysis for applying NCES to cells and mice, respectively, and the real EF strengths were measured. The change of loading voltage which had no effect on the regular pattern of EF distribution could be used as a single factor to explore the effect of NCES on wound healing. It was subsequently demonstrated that 53 mV mm^-1 NCES facilitated the migration and proliferation of HaCaT cells and HDFs in vitro, and the M2-type polarization of macrophages. Moreover, 54 and 84 mV mm^-1 NCESs accelerated the wound healing rate of model mice from the perspective of reducing scarring, enhancing collagen synthesis and increasing angiogenesis in vivo. The promoting role of NCES in wound healing showed the potential to initiate new possibilities for the clinical treatment of skin tissue injuries.