JAM-A knockdown accelerates the proliferation and migration of human keratinocytes, and improves wound healing in rats via FAK/Erk signaling

Cell Death Dis. 2018 Aug 28;9(9):848. doi: 10.1038/s41419-018-0941-y.

Abstract

Junctional adhesion molecule-A (JAM-A) belongs to the immunoglobulin superfamily, it predominantly exists at the tight junctions of epithelial and endothelial cells. JAM-A is known to regulate leukocyte trans-endothelial migration, however, how it affects the proliferation and migration of keratinocytes, the two essential steps during wound healing, has less been explored. In this study, we showed that JAM-A was significantly expressed in normal skin epidermis. RNAi-mediated JAM-A knockdown remarkably promoted the proliferation and migration of keratinocytes. We also found that loss of JAM-A increased the protein levels of p-FAK, p-Erk1/2, and p-JNK; however, FAK inhibitor PF-562271 restrained the expression of p-FAK and p-Erk1/2 elevated by JAM-A RNAi, but not p-JNK, and also slowed down keratinocyte proliferation and migration. Finally, in a rat wound model we showed that absence of JAM-A significantly promoted the wound healing process, while the use of PF-562271 or Erk1/2 inhibitor PD98059 repressed those effects. These data collectively demonstrate that suppressing JAM-A expression could promote the proliferation and migration of keratinocytes and accelerate the healing process of rat skin wounds, potentially via FAK/Erk pathway, indicating that JAM-A might serve as a potential therapeutic target for the treatment of chronic refractory wounds.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Adhesion Molecules / metabolism*
  • Cell Movement / physiology*
  • Cell Proliferation / physiology*
  • Cells, Cultured
  • Endothelial Cells / metabolism
  • Endothelial Cells / physiology
  • Epidermis / metabolism
  • Epidermis / physiology
  • Focal Adhesion Kinase 1 / metabolism*
  • Humans
  • Keratinocytes / metabolism*
  • Keratinocytes / physiology
  • MAP Kinase Signaling System / physiology*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Cell Surface / metabolism*
  • Signal Transduction / physiology
  • Wound Healing / physiology*

Substances

  • Cell Adhesion Molecules
  • F11R protein, human
  • Receptors, Cell Surface
  • Focal Adhesion Kinase 1
  • Ptk2 protein, rat