Effects of photobiomodulation therapy on functional recovery, angiogenesis and redox status in denervated muscle of rats
Jéssica Junia Aparecida Cardoso Nascimento, Alex Sander Dias Machado, Giovanna Moura Della Santa Lamas, Danielle Cristina Fernandes, Marcílio Coelho Ferreira, Gustavo Augusto Pereira Machado, Bruna Carolina Garcia Chaves, Karine Beatriz Costa, Etel Rocha‐Vieira, Murilo Xavier Oliveira, Thaís Peixoto Gaiad, Ana Paula Santos
Abstract
OBJECTIVE: To evaluate the effects of photobiomodulation therapy in redox status, angiogenesis marker - vascular endothelial growth factor - and in the functional recovery in denervated muscle. METHODS: A total of 32 female Wistar rats underwent a crush injury and were randomly divided into four groups: Light Emitting Diode Group 2 and Control Group 2 (muscle collected 2 days after injury), and Light Emitting Diode Group 21 and Control Group 21 (muscle collected 21 days afterinjury). Light Emitting Diode Group 2 and Light Emitting Diode Group 21 received two and ten light emitting diode applications (630±20nm, 9J/cm2, 300mW), respectively, and the Control Group 2 and Control Group 21 did not receive any treatment. The function was evaluated by grasping test at four moments (pre-injury, 2, 10 and 21 post-injury days). The flexor digitorum muscle was collected for analysis of immunolocalization of vascular endothelial growth factor and redox parameters. RESULTS: Functional improvement was observed at the second and tenth post-injury day in treated groups compared to control (p<0.005). The muscle tissue of treated groups presented higher immunohistochemical expression of vascular endothelial growth factor. Photobiomodulation therapy decreased the oxidative damage to lipid in Light Emitting Diode Group 2 compared to Control Group 2 (p=0.023) in the denervated muscle. CONCLUSION: Photobiomodulation therapy accelerated the functional recovery, increased angiogenesis and reduced lipid peroxidation in the denervated muscle at 2 days after injury.