Low-level laser irradiation promotes the proliferation and maturation of keratinocytes during epithelial wound repair

J Biophotonics. 2015 Oct;8(10):795-803. doi: 10.1002/jbio.201400064. Epub 2014 Nov 20.

Abstract

Low-level laser therapy (LLLT) has been extensively employed to improve epithelial wound healing, though the exact response of epithelium maturation and stratification after LLLT is unknown. Thus, this study aimed to assess the in vitro growth and differentiation of keratinocytes (KCs) and in vivo wound healing response when treated with LLLT. Human KCs (HaCaT cells) showed an enhanced proliferation with all the employed laser energy densities (3, 6 and 12 J/cm(2) , 660 nm, 100 mW), together with an increased expression of Cyclin D1. Moreover, the immunoexpression of proteins related to epithelial proliferation and maturation (p63, CK10, CK14) all indicated a faster maturation of the migrating KCs in the LLLT-treated wounds. In that way, an improved epithelial healing was promoted by LLLT with the employed parameters; this improvement was confirmed by changes in the expression of several proteins related to epithelial proliferation and maturation. Immunofluorescent expression of cytokeratin 10 (red) and Cyclin D1 (green) in (A) Control keratinocytes and (B) Low-level laser irradiated cells. Blue color illustrates the nuclei of the cells (DAPI staining).

Keywords: Cyclin D1; HaCaT keratinocytes; keratins; low-level laser therapy; p63 protein; photobiomodulation; wound healing.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation / radiation effects
  • Cell Line
  • Cell Movement / radiation effects
  • Cell Proliferation / radiation effects
  • Epithelium / radiation effects
  • Female
  • Humans
  • Keratinocytes / cytology*
  • Keratinocytes / metabolism
  • Keratinocytes / radiation effects*
  • Keratins / metabolism
  • Low-Level Light Therapy*
  • Rats
  • Rats, Wistar
  • Wound Healing / radiation effects*

Substances

  • Keratins