Direct Current Electric Field Coordinates the Migration of BV2 Microglia via ERK/GSK3β/Cofilin Signaling Pathway

Direct current electric field (DCEF) steers the migration of various neural cells. Microglia, as macrophage of the central nervous system (CNS), however, have not been reported to engage in electrotaxis. Here, we applied electric fields to an in vitro environment and found directional migration of BV2 microglia toward the cathode, in a DCEF strength-dependent manner. Transcriptome analysis then revealed significant changes in the mitogen-activated protein kinase cascades. In terms of mechanism, DCEF coordinated microglia movement by regulating the ERK/GSK3β/cofilin signaling pathway, and PMA (protein kinase C activator) reversed cell migration through intervention of the ERK/GSK3β/cofilin axis. Meanwhile, LiCl (GSK3β inhibitor) showed similar functions to PMA in the electrotaxis of microglia. Furthermore, pharmacological and genetic suppression of GSK3β or cofilin also modulated microglia directional migration under DCEF. Collectively, we discovered the electrotaxis of BV2 microglia and the essential role of the ERK/GSK3β/cofilin axis in regulating cell migration via modulation of F-actin redistribution. This research highlights new insight toward mediating BV2 directional migration and provides potential direction for novel therapeutic strategies of CNS diseases.