Effects of microelectrical current on migration of nasal fibroblasts

Background: Migration of fibroblasts is critical in wound healing. The question of how wounded electric fields guide migration of nasal fibroblasts remains to be elucidated. This study was designed to determine morphology, directedness, and migration rate of nasal fibroblasts during microcurrent application, which is simulated by an endogenous electric field at the vicinity of the wound. Methods: Nasal fibroblasts were exposed to a microelectric field at 50, 100, and 250 mV/mm for 3 hours at 37°C. In this experiment, the field polarity was reversed for an additional 3 hours. During in vitro testing, the cells were incubated in a newly developed miniature, microcurrent generating chamber system, with 5% CO₂, at 37°C; the media was circulated by a pump system. A wound was created by scratching a cell-free area (∼150 μm wide) into a confluent monolayer. The average migration speed was calculated as the distance traveled by the cell divided by time. Results: A microelectric field of 100 mV/mm or more induced significant cell migration in the direction of the cathode. Trajectory speeds at 50, 100, and 250 mV/mm were 9.8 ± 0.3, 11.8 ± 0.3, and 13.5 ± 0.9 μm/mm, respectively. A significant difference was observed between migratory rate of controls and that of 50 mV/mm (p < 0.05). Conclusion: Microelectric fields appear to have a crucial role in control of nasal fibroblast activity in the process of wound healing.