Pulsed electrical stimulation modulates fibroblasts' behaviour through the Smad signalling pathway

Abstract

The aim of this study was to investigate the healing characteristics and the underlying signalling pathway of human dermal fibroblasts under the influence of pulsed electrical stimulation (PES). Primary human dermal fibroblasts were seeded on polypyrrole-coated polyester fabrics and subjected to four different PES protocols. The parameters of the rectangular pulse included potential intensity (50 and 100 mV/mm) and stimulation time (pulse width 300 s within a period of 600 s, and pulse width 10 s within a period of 1200 s). Our study revealed that PES moderately improved the ability of the cells to migrate in association with a statistically significant (p < 0.05) increase of FGF2 secretion by the PES-exposed fibroblasts. These exposed fibroblasts were able to contract collagen gel matrix up to 48 h and this collagen gel contraction paralleled an increase in α-SMA mRNA expression and protein production from the PES-exposed fibroblasts. Interestingly, the effect of PES on the human fibroblasts involved the Smad signalling pathway, as we observed higher levels of phosphorylated Smad2 and Smad3 in the stimulated groups compared to the control groups. Overall, this study demonstrated that PES modulates fibroblast activities through the Smad signalling pathway, thus providing new mechanistic insights related to the use of PES to promote wound healing in humans. Copyright © 2015 John Wiley & Sons, Ltd.