Tissue Responses to Postoperative Laser Therapy in Diabetic Rats Submitted to Excisional Wounds

Author(s):Show less -

Santana, Cristiano de Loura ^[1] ; Teixeira Silva, Daniela de Fatima ^[1] ; Deana, Alessandro Melo ^[1] ; Prates, Renato Araujo ^[1] ; Souza, Amanda Pires ^[1] ; Gomes, Mariana Teixeira ^[1] ; de Azevedo Sampaio, Brunna Pileggi ^[1] ; Shibuya, Josiane Ferraretto ^[1] ; Bussadori, Sandra Kalil ^[1] ; Mesquita-Ferrari, Raquel Agnelli ^[1] ; Santos Fernandes, Kristianne Porta ^[1] ; Franca, Cristiane Miranda ^[1]

Affiliation

^[1] Univ Nove de Julho UNINOVE, Postgrad Program Biophoton Appl Hlth Sci, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: PLoS One; v. 10, n. 4 APR 24 2015.
• Web of Science Citations: 12

Abstract

In a previous study about low-level laser therapy biomodulation on a full-thickness burn model we showed that single and fractionated dose regimens increased wound healing and leukocyte influx similarly when compared with untreated control. In order to verify if this finding would be similar in an impaired wound model, we investigated the effect of single and multiple irradiations on wound closure rate, type of inflammatory infiltrate, myofibroblasts, collagen deposition, and optical retardation of collagen in diabetic rats. Female Wistar rats in the same estrous cycle had diabetes induced with streptozotocin and an 8-mm excisional wound performed with a punch. The experimental groups were: control group - untreated ulcer; single-dose group - ulcer submitted to single dose of diode laser therapy (lambda = 660 +/- 2 nm; P = 30 mW; energy density: 4 J/cm(2)) and fractionated-dose group - ulcer submitted to 1 J/cm(2) laser therapy on Days 1, 3, 8, and 10. The ulcers were photographed on the experimental days and after euthanasia tissue samples were routinely processed for histological and immunohistochemistry analyses. Independently of the energy density, laser therapy accelerated wound closure by approximately 40% in the first three days in comparison to the control group. Laser therapy increased acute inflammatory infiltrate until Day 3. Both laser groups exhibited more myofibroblasts and better collagen organization than the control group. The findings demonstrate that low-level laser therapy in the immediate postoperative period can enhance the tissue repair process in a diabetes model. Similar effects were achieved with laser therapy applied a single time with an energy density of 4 J/cm(2) and applied four times with an energy density of 1 J/cm(2). The application of laser therapy in the inflammatory phase was the most important factor to the enhancement of the tissue repair process. (AU)

• FAPESP's process: 12/03334-4 - Organization of collagen in skin repair of diabetic mice when treated with low-power laser: comparison of energy densities
• Grantee: Josiane Aparecida Ferraretto Shibuya
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 12/02801-8 - Influence of two systems of delivery of low-intensity laser in skin repair in diabetic rats: morphological evaluation, myofibroblasts and collagens I and III
• Grantee: Brunna Pileggi Azevedo Sampaio
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 12/01944-0 - Study of cell activation and cytokines in cutaneous repair in diabetic rats treated with low level laser therapy
• Grantee: Cristiane Miranda Franca
• Support Opportunities: Regular Research Grants