Artículos de revistas
GaAs 904-nm laser irradiation improves myofiber mass recovery during regeneration of skeletal muscle previously damaged by crotoxin
Fecha
2012-09Registro en:
LASERS IN MEDICAL SCIENCE, LONDON, v. 27, n. 5, pp. 993-1000, SEP, 2012
0268-8921
10.1007/s10103-011-1031-x
Autor
Silva, Lucila H.
Silva, Meiricris T.
Gutierrez, Rita M.
Conte, Talita C.
Toledo, Claudio A.
Aoki, Marcelo S.
Liebano, Richard E.
Miyabara, Elen H.
Institución
Resumen
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.