Low-level laser therapy induces an upregulation of collagen gene expression during the initial process of bone healing: a microarray analysis

作者：Tim Carla Roberta; Bossini Paulo Sergio; Kido Hueliton Wilian; Malavazi Iran; Kress Marcia Regina von Zeska; Carazzolle Marcelo Falsarella; Renno Ana Claudia; Parizotto Nivaldo Antonio

来源：Journal of Biomedical Optics, 2016, 21(8): 088001.

DOI：10.1117/1.JBO.21.8.088001

• bone regeneration
• low level laser therapy
• microarray
• collagen

This study investigates the histological modifications produced by low level laser therapy (LLLT) on the first day of bone repair, as well as evaluates the LLLT effects on collagen expression on the site of a fracture. Twenty Wistar rats were distributed into a control group (CG) and a laser group (LG). Laser irradiation of Ga-AlAs laser 830 nm, 30 mW, 94 s, 2.8 J was performed in five sessions. Animals were euthanized on day 5 post-surgery. Histopathological analysis showed that LLLT was able to increase deposition of granulation tissue and newly formed bone at the site of the injury. In addition, picrosirius analysis showed that collagen fiber organization in the LG was enhanced compared to CG. Microarray analysis demonstrated that LLLT produced an upregulation type I collagen (COL-I). Immunohistochemical analysis revealed that the subjects that were treated presented a higher immunoexpression of COL-I. Our findings indicated that LLLT improves bone healing by producing a significant increase in the expression of collagen genes.

• 出版日期2016-8