Low‐level light pre‐conditioning promotes C2C12 myoblast differentiation under hypoxic conditions

Abstract

Exercise, especially anaerobic one, can gradually increase muscle mass over time as a result of adaptive responses of muscle cells to ensure metabolic homeostasis in the tissue. Low‐level light therapy (LLLT) or photobiomodulation exhibits beneficial effects on promoting muscular functions, regeneration, and recovery from exhausting exercise, although the underlying cellular mechanisms remain poorly understood. We found that hypoxia, a condition following anaerobic exercise, significantly impeded myotube differentiation from myoblasts. However, this adverse effect was blunted greatly by pre‐exposure of myoblast cells to a 980 nm laser at 0.1 J/cm2, resulting in almost nearly normal myotube differentiation. LLL pre‐treatment enhanced myotube formation by 80%, with a tubular diameter of 4.28 ± 0.11 μm on average, representative of a 53.4% increase over sham light treatment. The normalized myoblast differentiation concurred with 68% more mitochondrial mass and myogenin expression over controls. Moreover, LLL pre‐treatment appeared to enhance glucose uptake, prevent energy metabolic switch from oxidative phosphorylation to glycolysis, and diminish lactate production under hypoxic conditions. The observation provides valuable guidance with respect to the timing of LLLT and its potential effects on muscle strengths in concert with anaerobic exercise.

Rectifying the impairment of immune thrombocytopenia plasmas through photobiomodulation

“…21 More-0% 2% 4% 8% 10% 15% over, inhibition of ATP synthase almost entirely abolished the effects of 980 nm laser on ATP synthesis, whereas inhibition of cytochrome c oxidase did not impede the increase in ATP levels in response to the 980 nm laser. 22 Similar photobiomodulation of 980 nm and 810 nm lasers has been also observed in various cell types, including fetal liver and bone marrow MKs, myoblasts, osteoblasts, periodontal ligament mesenchymal stem cells, keratinocytes, and fibroblasts. 17,[22][23][24] Nevertheless, MKs seem much more sensitive to 980 nm laser than 810 nm laser, making 980 nm laser or LED more appealing for clinical application.…”

“…22 Similar photobiomodulation of 980 nm and 810 nm lasers has been also observed in various cell types, including fetal liver and bone marrow MKs, myoblasts, osteoblasts, periodontal ligament mesenchymal stem cells, keratinocytes, and fibroblasts. 17,[22][23][24] Nevertheless, MKs seem much more sensitive to 980 nm laser than 810 nm laser, making 980 nm laser or LED more appealing for clinical application. This is because it would be more practical to deliver such a low dose of 980 nm laser (0.03 J/cm 2 ) into internal organs noninvasively, in contrast to 810 nm laser, which requires a 100-fold higher energy density (3 J/cm 2 ).…”

Photobiomodulation mitigates Bothrops jararacussu venom-induced damage in myoblast cells by enhancing myogenic factors and reducing cytokine production

“…PBMT has been reported to exert a beneficial influence on muscle regeneration. This is achieved through its capacity to stimulate the proliferation of muscle and satellite cells, enhancing protein synthesis in myoblasts, increasing the area of muscle fibers, enhance mitochondrial density [14][15][16][17], and upregulate the expression of myogenic regulatory factor, including pax7, myoD, and myogenin [15,[18][19].…”