de Araújo Carlos E N, Ribeiro Martha S, Favaro Rodolfo, Zezell Denise M, Zorn Telma M T
Department of Cell and Development Biology, Institute of Biomedical Sciences, University of São Paulo, Av. Lineu Prestes, 1524, 05508-000 São Paulo, São Paulo, Brazil.
J Photochem Photobiol B. 2007 Feb 1;86(2):87-96. doi: 10.1016/j.jphotobiol.2006.08.006. Epub 2006 Oct 9.
There are evidences that low-intensity red laser radiation is capable to accelerate wound healing. Nowadays, this therapy has been gradually introduced in clinical practice although mechanisms underlying laser effects are poorly understood. To better understand the photobiological effects of laser radiation, this study investigated by electron microscopy, immunohistochemistry and autoradiography the morphological and functional features of irradiated and none irradiated injured mice skin. Full-thickness skin lesions were created on the back of mice and irradiated on days 1, 5, 8, 12, and 15 post-wounding with a He-Ne laser (lambda=632.8nm), dose 1J/cm(2), exposure time 3min. Non-irradiated lesions were used as a control. The mice were inoculated with (3)H-proline and sacrificed one hour after on the 8th, 15th and 22nd days to histological and radioautographical analysis. The irradiated-lesions showed a faster reepithelization compared with control lesions. The irradiated dermis contained a higher number of activated fibroblasts compared to control group and, most of them showed several cytoplasmic collagen-containing phagosomes. In irradiated-lesions, smooth muscle alpha-actin positive cells predominated, which correspond to a higher number of myofibroblasts observed in the electron microscope. Moreover, laser radiation reduced the local inflammation and appears to influence the organization of collagen fibrils in the repairing areas. Quantitative autoradiography showed that the incorporation of (3)H-proline was significantly higher in irradiated-dermis on the 15th day post-wounding (p<0.05). These results suggest that laser radiation may accelerate cutaneous wound healing in a murine model.
有证据表明，低强度红色激光辐射能够加速伤口愈合。如今，这种疗法已逐渐引入临床实践，尽管激光作用的潜在机制尚不清楚。为了更好地理解激光辐射的光生物学效应，本研究通过电子显微镜、免疫组织化学和放射自显影术，研究了照射和未照射的受伤小鼠皮肤的形态和功能特征。在小鼠背部制造全层皮肤损伤，并在受伤后第1、5、8、12和15天用氦氖激光（波长=632.8nm）照射，剂量为1J/cm²，照射时间为3分钟。未照射的损伤用作对照。给小鼠接种³H-脯氨酸，并在第8、15和22天接种一小时后处死，进行组织学和放射自显影分析。与对照损伤相比，照射损伤显示出更快的上皮再形成。与对照组相比，照射的真皮中含有更多活化的成纤维细胞，并且大多数成纤维细胞显示出几个含有细胞质胶原的吞噬体。在照射损伤中，平滑肌α-肌动蛋白阳性细胞占主导，这与在电子显微镜下观察到的更多肌成纤维细胞相对应。此外，激光辐射减轻了局部炎症，并且似乎影响修复区域中胶原纤维的组织。定量放射自显影显示，在受伤后第15天，照射真皮中³H-脯氨酸的掺入量显著更高（p<0.05）。这些结果表明，激光辐射可能会加速小鼠模型中的皮肤伤口愈合。
