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.

Using Pre-Exercise Photobiomodulation Therapy Combining Super-Pulsed Lasers and Light-Emitting Diodes to Improve Performance in Progressive Cardiopulmonary Exercise Tests

“…33 The simultaneous use of different wavelengths may increase the effects of phototherapy on skeletal muscle performance and may represent a therapeutic advantage in the clinical situations observed in this study and previous studies. 12,24,27,30,31 Finally, our results were due to desirable photobiomodulatory effects of light and not to thermal effects. 26 They were also in line with current evidence that PBMT before exercise has ergogenic effects.…”

“…Whereas De Marchi et al 23 used 5 diodes of 810-nm infrared laser, we used different light sources simultaneously (4 3 905-nm superpulsed laser, 4 3 875-nm infrared LEDs, and 4 3 640-nm red LEDs) to irradiate our volunteers. Researchers have shown that a combination of different light sources enhances muscular performance, 24,27 decreases pain, 30 increases cytochrome c oxidase activity, 12 decreases fatigue development, and protects muscles against gradually worsening damage. 31 Whereas De Marchi et al 23 reported a difference for oxygen uptake between groups, the clinical importance of these differences remains uncertain.…”

“…Albuquerque-Pontes et al 12 irradiated the tibialis anterior muscle of rats using different wavelengths (660, 830, or 905 nm) and reported an increase in cytochrome c oxidase activity in different time windows (5 minutes to 24 hours after irradiation). This finding contributes to the understanding of mechanisms through which PBMT enhances muscular performance and protects muscles against fatigue and tissue damage.…”

“…5 Recently, photobiomodulation therapy (PBMT) using low-level lasers or light-emitting diodes (LEDs) has been described as an electrophysical intervention that provides beneficial effects on muscular activity. [6][7][8] Researchers studying the application of PBMT before high-intensity exercises 9 have shown an increase in blood-lactate removal and a reduction in muscle injuries resulting in faster muscle recovery, 10,11 increased mitochondrial function through the modulation of cytochrome c oxidase, 12 and changes in the ionic gradient. 13 In many studies, [14][15][16] PBMT has been used as a noninvasive therapeutic modality to optimize vasodilation, improve collateral circulation, increase tissue oxygen levels, and enhance mitochondrial adenosine triphosphate levels.…”

Analysis of Radiomodulatory Effect of Low-Level Laser Irradiation by Clonogenic Survival Assay

“…Dose-response of LLLI depends on cell types and illumination parameters such as wavelength, power density, energy density, pulse structure, and treatment timing. [36][37][38] The dose-response effect of the LLLI is biphasic. 24 Lower energy densities of LLLI have a beneficial effect on stimulating and repairing cells and tissues, but higher energy densities have inhibitory effects, such as induction of apoptosis.…”