Effect of low-level laser therapy (660 nm) on the healing of second-degree skin burns in rats

J Cosmet Laser Ther. 2011 Oct;13(5):237-42. doi: 10.3109/14764172.2011.606466.

Abstract

The aim of this study was to investigate the effects of 660 nm laser on the healing of burn wounds made on the backs of rats. Thirty-two Wistar male rats were used. The animals were randomly distributed into 2 groups of 16 animals each: control group (burned rats without treatment) and laser-treated group (burned rats treated with laser therapy). Each group was divided into two different subgroups, euthanized in different periods (subgroup A: 7 days post-surgery and subgroup B: 14 days post-surgery). Histopathological analysis revealed a significant decrease in the necrotic area in the laser-treated group compared to the controls at days 7 and 14 post-injury. COX-2 positive cells were found in a strong pattern in the group submitted to laser therapy after 7 days. Regarding VEGF immunomarker, a significant VEGF immunoexpression was detected in the laser-exposed group after 14 days when compared to the negative control group. Taken together, our results demonstrate that laser therapy is able to promote skin repair of burned rats as a result of decreasing necrotic area and an up-regulation of COX-2 and VEGF immunoexpression.

MeSH terms

  • Analysis of Variance
  • Animals
  • Burns / metabolism
  • Burns / pathology
  • Burns / radiotherapy*
  • Cyclooxygenase 2 / metabolism
  • Low-Level Light Therapy*
  • Male
  • Necrosis
  • Rats
  • Rats, Wistar
  • Skin / pathology
  • Vascular Endothelial Growth Factor A / metabolism
  • Wound Healing / radiation effects*

Substances

  • Vascular Endothelial Growth Factor A
  • Cyclooxygenase 2