Pulsed electromagnetic fields modulate energy metabolism during wound healing process: an in vitro model study

Pulsed electromagnetic fields (PEMFs) therapy was extensively investigated to treat wound healing, which is a highly metabolically demanding process. However, the effect of PEMFs on energy metabolism in wound healing remains largely unexplored. Therefore, our study aims to demonstrate the role of PEMFs on energy metabolism in wound healing.

Scratch-wound healing assay and cell viability assay were performed for the in vitro study of the effect of PEMFs on cell migration and viability. Seahorse assay was conducted for energy metabolism analysis while holo-tomographic microscopy for fine changes of L929 cells. Mitochondrial membrane potential assay and intracellular reactive oxygen species (ROS) and pH assay were performed for analyzing the changes of mitochondrial function.

PEMFs with specific parameter (4mT, 80 Hz) promoted cell migration and viability. Glycolysis stress and mitochondria stress test revealed that PEMFs-exposed L929 cells was highly glycolytic for energy generation. Besides, PEMFs enhanced intracellular acidification and maintained low level of intracellular ROS in L929 cells. Compared to control group, much more vesicles were generated and then transported to regions close to the nuclear in L929 cells treated with PEMFs.

Our major findings revealed for the first time that PEMFs induce metabolic reprogramming of fibroblast shifting from mitochondrial respiration to glycolysis, accompanied with an increase of vesicular transport, which is closely related to wound healing in vitro.