GaAs 904-nm laser irradiation improves myofiber mass recovery during regeneration of skeletal muscle previously damaged by crotoxin

Autor(es)

Silva, Lucila H. ^[1] ; Silva, Meiricris T. ^[1] ; Gutierrez, Rita M. ^[2] ; Conte, Talita C. ^[1] ; Toledo, Claudio A. ^[2] ; Aoki, Marcelo S. ^[3] ; Liebano, Richard E. ^[2] ; Miyabara, Elen H. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Anat, Inst Biomed Sci, BR-05508000 Sao Paulo - Brazil

^[2] Univ Sao Paulo City, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Sch Art Sci & Humanities, BR-05508000 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Medical Science; v. 27, n. 5, p. 993-1000, SEP 2012.
• Citações Web of Science: 9

Resumo

This work investigated the effect of gallium arsenide (GaAs) irradiation (power: 5 mW; intensity: 77.14 mW/cm(2), spot: 0.07 cm(2)) on regenerating skeletal muscles damaged by crotoxin (CTX). Male C57Bl6 mice were divided into six groups (n = 5 each): control, treated only with laser at doses of 1.5 J or 3 J, CTX-injured and, CTX-injured and treated with laser at doses of 1.5 J or 3 J. The injured groups received a CTX injection into the tibialis anterior (TA) muscle. After 3 days, TA muscles were submitted to GaAs irradiation at doses of 1.5 or 3 J (once a day, during 5 days) and were killed on the eighth day. Muscle histological sections were stained with hematoxylin and eosin (H\&E) in order to determine the myofiber cross-sectional area (CSA), the previously injured muscle area (PIMA) and the area density of connective tissue. The gene expression of MyoD and myogenin was detected by real-time PCR. GaAs laser at a dose of 3 J, but not 1.5 J, significantly increased the CSA of regenerating myofibers and reduced the PIMA and the area density of intramuscular connective tissue of CTX-injured muscles. MyoD gene expression increased in the injured group treated with GaAs laser at a dose of 1.5 J. The CTX-injured, 3-J GaAs laser-treated, and the CTX-injured and treated with 3-J laser groups showed an increase in myogenin gene expression when compared to the control group. Our results suggest that GaAs laser treatment at a dose of 3 J improves skeletal muscle regeneration by accelerating the recovery of myofiber mass. (AU)

• Processo FAPESP: 09/54240-7 - Papel do adrenocpetor beta 2 na regeneracao muscular esqueletica
• Beneficiário: Meiricris Tomaz da Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 07/56879-0 - Influencia do mtorc-1 (mammalian target of rapamycin complex 1) sobre aspectos morfologicos e moleculares da regeneracao de musculos esqueleticos de ratos jovens e idosos.
• Beneficiário: Talita Cristiane Conte
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 09/50198-6 - Efeito da laserterapia de baixa potencia sobre aspectos morfomoleculares do tecido muscular esquelético em regeneração
• Beneficiário: Lucila Hernandes da Silva
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica