title: Effect of pre-irradiation with different doses, wavelengths, and application intervals of low-level laser therapy on cytochrome c oxidase activity in intact skeletal muscle of rats.
abstract: Modulation of cytochrome c oxidase activity has been pointed as a possible key mechanism for low-level laser therapy (LLLT) in unhealthy biological tissues. But recent studies by our research group with LLLT in healthy muscles before exercise found delayed skeletal muscle fatigue development and improved biochemical status in muscle tissue. Therefore, the aim of this study was to evaluate effects of different LLLT doses and wavelengths in cytochrome c oxidase activity in intact skeletal muscle. In this animal experiment, we irradiated the tibialis anterior muscle of rats with three different LLLT doses (1, 3, and 10 J) and wavelengths (660, 830, and 905 nm) with 50 mW power output. After irradiation, the analyses of cytochrome c oxidase expression by immunohistochemistry were analyzed at 5, 10, 30 min and at 1, 2, 12, and 24 h. Our results show that LLLT increased (p < 0.05) cytochrome c oxidase expression mainly with the following wavelengths and doses: 660 nm with 1 J, 830 nm with 3 J, and 905 nm with 1 J at all time points. We conclude that LLLT can increase cytochrome c oxidase activity in intact skeletal muscle and that it contributes to our understanding of how LLLT can enhance performance and protect skeletal muscles against fatigue development and tissue damage. Our findings also lead us to think that the combined use of different wavelengths at the same time can enhance LLLT effects in skeletal muscle performance and other conditions, and it can represent a therapeutic advantage in clinical settings.
authors: Postgraduate Program in Biophotonics Applied to Health Sciences, Universidade Nove de Julho (UNINOVE), Rua Vergueiro, 235, São Paulo, SP, 01504-001, Brazil.
authors: Gianna Móes
authors: GM
authors: Albuquerque-Pontes
authors: Rodolfo de Paula
authors: RP
authors: Vieira
authors: Shaiane Silva
authors: SS
authors: Tomazoni
authors: Cláudia Oliveira
authors: CO
authors: Caires
authors: Victoria
authors: V
authors: Nemeth
authors: Adriane Aver
authors: AA
authors: Vanin
authors: Larissa Aline
authors: LA
authors: Santos
authors: Henrique Dantas
authors: HD
authors: Pinto
authors: Rodrigo Labat
authors: RL
authors: Marcos
authors: Jan Magnus
authors: JM
authors: Bjordal
authors: Paulo de Tarso Camillo
authors: Pde T
authors: de Carvalho
authors: Ernesto Cesar Pinto
authors: EC
authors: Leal-Junior
mesh_terms: D000818:Animals; D004307:Dose-Response Relationship, Radiation; D003576:Electron Transport Complex IV / Q000378:metabolism*; D007150:Immunohistochemistry; D028022:Low-Level Light Therapy; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000201:enzymology / Q000528:radiation effects; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000528:radiation effects*; D017208:Rats, Wistar
chemical_list: D003576:Electron Transport Complex IV