The Galvanotactic Migration of Keratinocytes is Enhanced by Hypoxic Preconditioning

Sci Rep. 2015 May 19:5:10289. doi: 10.1038/srep10289.

Abstract

The endogenous electric field (EF)-directed migration of keratinocytes (galvanotaxis) into wounds is an essential step in wound re-epithelialization. Hypoxia, which occurs immediately after injury, acts as an early stimulus to initiate the healing process; however, the mechanisms for this effect, remain elusive. We show here that the galvanotactic migration of keratinocytes was enhanced by hypoxia preconditioning as a result of the increased directionality rather than the increased motility of keratinocytes. This enhancement was both oxygen tension- and preconditioning time-dependent, with the maximum effects achieved using 2% O2 preconditioning for 6 hours. Hypoxic preconditioning (2% O2, 6 hours) decreased the threshold voltage of galvanotaxis to < 25 mV/mm, whereas this value was between 25 and 50 mV/mm in the normal culture control. In a scratch-wound monolayer assay in which the applied EF was in the default healing direction, hypoxic preconditioning accelerated healing by 1.38-fold compared with the control conditions. Scavenging of the induced ROS by N-acetylcysteine (NAC) abolished the enhanced galvanotaxis and the accelerated healing by hypoxic preconditioning. Our data demonstrate a novel and unsuspected role of hypoxia in supporting keratinocyte galvanotaxis. Enhancing the galvanotactic response of cells might therefore be a clinically attractive approach to induce improved wound healing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Hypoxia / physiology*
  • Cell Movement / physiology*
  • Cells, Cultured
  • Electricity
  • Ischemic Preconditioning*
  • Keratinocytes / physiology*
  • Mice
  • Mice, Inbred BALB C
  • Re-Epithelialization / physiology*
  • Reactive Oxygen Species / metabolism
  • Skin / injuries
  • Wound Healing / physiology

Substances

  • Reactive Oxygen Species