Table of Contents
Laser Chemistry
Volume 2007, Article ID 71039, 10 pages
Research Article

Changes in Cell Viability of Wounded Fibroblasts following Laser Irradiation in Broad-Spectrum or Infrared Light

Laser Research Group, Faculty of Health, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, Johannesburg, South Africa

Received 29 June 2006; Revised 14 August 2006; Accepted 22 August 2006

Academic Editor: Frederik Claeyssens

Copyright © 2007 Denise Hawkins and Heidi Abrahamse. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Objective. This study aimed to establish if broad-spectrum or infrared (IR) light in combination with laser therapy can assist phototherapy to improve the cell function of wounded cells. Background. The effect of laser light may be partly or completely reduced by broad-spectrum light. Methods. Wounded human skin fibroblasts were irradiated with 5 J/cm2 using a helium-neon laser, a diode laser, or an Nd:YAG laser in the dark, in the light, or in IR. Changes in cell viability were evaluated by cell morphology, ATP cell viability, LDH membrane integrity, and caspase 3/7 as an early marker of apoptosis. Results. Wounded cells exposed to 5 J/cm2 using 632.8 nm in the dark or 830 nm in the light or 1064 nm in the dark showed an increase in ATP viability, an increase in cytokine expression, and a decrease in LDH cytotoxicity indicating that the metabolic activity of the wounded cells was stimulated. Conclusion. Wounded cells irradiated in IR light showed an undesirable thermal effect that was proportional to the duration of exposure.