Effects of photostimulation on wound healing in diabetic mice

Abstract

Background and objective: Low-level laser irradiation at certain fluences and wavelengths can enhance the release of growth factors from fibroblasts and stimulate cell proliferation in vitro. We evaluated whether low-level laser irradiation can improve wound healing in diabetes mellitus.

Study design/materials and methods: Genetically diabetic mice (C57BL/Ksj/db/db) were used as the animal model for this wound healing study. The experimental animals were divided among four groups: negative control, positive control (topical basic fibroblast growth factor [bFGF] on wound), laser therapy group; and a combination group of laser therapy and topical bFGF. An argon dye laser (Lexel Auora Model 600) at a wavelength of 630 nm and an output of 20 m W/cm2 was used as the light source. The speed of wound closure and histological evaluation were used to analyze the experimental results.

Results: Laser irradiation enhanced the percentage of wound closure over time as compared to the negative control group (58.4 +/- 2.6 vs. 40.8 +/- 3.4 at day 10 and 95.7 +/- 2 vs. 82.3 +/- 3.6 at day 20, P < .01). Histological evaluation showed that laser irradiation improved wound epithelialization, cellular content, granulation tissue formation, and collagen deposition in laser-treated wounds as compared to the negative control group (6.4 +/- 0.16 vs. 3.8 +/- 0.13 at day 10 and 12 +/- 0.21 vs. 8.2 +/- 0.31, P < .01).

Conclusion: This study of laser biostimulation on wound healing in diabetic mice suggests that such therapy may be of great benefit in the treatment of chronic wounds that occur as a complication of diabetes mellitus.