Combined carbon photon and hydrogel therapy mediates the synergistic repair of full-thickness skin wounds

Abstract

Objective: This study investigated the synergistic repair effects of Prontosan hydrogel and carbon photon therapy in a rat full-thickness wound model.

Methods: The wavelength distribution of the photon source was determined. Dehydration of the Prontosan hydrogel and fibroblast viability were analyzed following exposure to different durations of light exposure at different distances from the source. Indexes of wound healing in a full-thickness rat wound model were then determined in groups (n = 8 each) subjected to either no treatment, Prontosan treatment only, carbon photon therapy only, or a combination of the two treatments (synergistic group).

Results: Carbon photon exposure for 15 minutes at a distance of 20 cm from the wound was found to be optimal. Wound healing occurred faster in the synergistic group compared with the control and single-treatment groups. Growth factor secretion, granulation tissue formation, inflammation regulation, collagen deposition, and neovascularization were all higher in the synergistic group.

Conclusions: Prontosan hydrogel combined with carbon photon therapy may provide an optimal environment for wound healing and serve as a novel physical approach to the treatment of wounds. However, the number of animals included in this study was relatively small and a larger study is required to confirm these findings.

Keywords: Carbon photon therapy; collagen; fibroblasts; granulation tissue; growth factors; hydrogel; neovascularization; synergistic treatment; wound repair.

Figure 1.

Wavelength distributions of carbon light source as determined by spectrometry between 200 and 660 nm.

Figure 2.

Gel dehydration rate of Prontosan hydrogel (a) and cell viability of fibroblasts (b) when subjected to different periods of light exposure at different distances from the light source. The percentage area of the wound defect (c) at different time points post-wounding in the four treatment groups. Data represent the mean ± SD, n = 4, *P < 0.05.

Figure 3.

Wound appearances at different timepoints post-wounding in the four treatment groups.

Figure 4.

Concentrations of TGF-β1 (a), VEGF (b), and bFGF (c) in regenerated tissue samples from the four experimental groups at 8 and 16 days post wounding. Data represent the mean ± SD, n = 3, *P < 0.05, **P < 0.01. TGF, transforming growth factor; VEGF, vascular endothelial growth factor; bFGF, basic fibroblast growth factor.

Figure 5.

Hematoxylin and eosin (H&E) staining and Masson trichrome staining of regenerated tissue samples from the four treatment groups at days 8 and 16. In the Masson trichrome-stained images, the collagen and nuclei stained blue and black, respectively, while the scar tissue, muscle, cytoplasm, and keratin stained red.

Figure 6.

Inflammatory cells (a), maturity score (b), and vessel number (c) in regenerated tissue samples from each treatment group at 8 and 16 days post wounding. Data represent the mean ± SD, n = 3, *P < 0.05, **P < 0.01.

Figure 7.

Immunohistochemical staining of K14 and CD31 in regenerated tissue samples from each treatment group at 8 and 16 days post wounding.