Exploring the ability of low-level laser irradiation to reduce myonecrosis and increase Myogenin transcription after Bothrops jararacussu envenomation

Abstract

Envenoming caused by snakebites is a very important neglected tropical disease worldwide. The myotoxic phospholipases present in the bothropic venom disrupt the sarcolemma and compromise the mechanisms of energy production, leading to myonecrosis. Photobiomodulation therapy (PBMT) has been used as an effective tool to treat diverse cases of injuries, such as snake venom-induced myonecrosis. Based on that, the aim of this study was to analyze the effects of PBMT through lowlevel laser irradiation (904 nm) on the muscle regeneration after the myonecrosis induced by Bothrops jararacussu snake venom (Bjssu) injection, focusing on myogenic regulatory factors expression, such as Pax7, MyoD, and Myogenin (MyoG). Male Swiss mice (Mus musculus), 6-8-week-old, weighing 22 ± 3 g were used. Single sub-lethal Bjssu dose or saline was injected into the right mice gastrocnemius muscle. At 3, 24, 48, and 72 h after injections, mice were submitted to PBMT treatment. When finished the periods of 48 and 72 h, mice were euthanized and the right gastrocnemius were collected for analyses. We observed extensive inflammatory infiltrate in all the groups submitted to Bjssu injections. PBMT was able to reduce the myonecrotic area at 48 and 72 h after envenomation. There was a significant increase of MyoG mRNA expression at 72 h after venom injection. The data suggest that beyond the protective effect promoted by PBMT against Bjssu-induced myonecrosis, the low-level laser irradiation was able to stimulate the satellite cells, thus enhancing the muscle repair by improving myogenic differentiation.

LEDT and Idebenone treatment modulate autophagy and improve regenerative capacity in the dystrophic muscle through an AMPK-pathway

“…The treatments lead to an advanced differentiation in the dystrophic muscle, by the down-regulation of MyoD levels and the up-regulation of myogenin levels. These data are in agreement with previous studies, which demonstrated improved myogenin expression in the muscle of the envenomation murine model due to the Bothrops jararacussu snake venom after PBMT [ 49 ] and modulation of the myogenic regulatory factors after multiple LEDT wavelengths [ 28 ]. In addition, we also identified the down-regulation of MHC-fast levels and up-regulation of MHC-slow levels after LEDT and IDE treatment.…”

Photobiomodulation for Major Depressive Disorder: Linking Transcranial Infrared Light, Biophotons and Oxidative Stress

“…21 This plethora of biological activities results in numerous therapeutic benefits beyond application to brain disorders. In fact, different preclinical studies suggest the applicability of PBM-induced biological effects to wound healing, 22 muscle regeneration, [23][24][25] and neuropathic pain, 26,27 among others. PBM has also been used to treat acute stroke, traumatic brain injury, 28 and several neurological and affective disorders, including MDD.…”

Efeito da fotobiomodulação na miosite: avaliação da nocicepção, inflamação e regeneração muscular.

“…Para tais medidas, as imagens foram previamente calibradas com auxílio da ferramenta "set scale" a partir da barra de calibração de 20 µm. Uma vez identificados os pixels de interesse, foi utilizada a ferramenta "analyze particles" [120]. Vale ressaltar que as análises do número e área de fibras com núcleos centralizados foram realizadas às cegas.…”