RESUMO
ABSTRACT This study aimed to investigate the effects of low-level laser therapy (LLLT) on muscle repair in rats with chronic alcohol intake. Thirty male Wistar rats were distributed into three groups: injured tibialis anterior (TA) muscle without treatment (IC); chronic ingestion of alcohol plus injured TA muscle (AI); and chronic ingestion of alcohol plus injured TA plus LLLT (AIL). Each group was divided into two different subgroups, and rats were sacrificed on days 3 and 7 post-injury. Morphological features in the injured areas were similar with or without alcohol intake (IC and AI); however, LLLT promoted a decrease in the number of inflammatory cells and destroyed zones, as well as improved tissue organization (AIL). In general, alcohol intake caused a decrease in myogenic regulatory factors (MyoD and myogenin) and vascular endothelial growth factor in the AI group. Moreover, LLLT promoted recovery of these factors to the same level as in animals without alcohol intake (IC and AIL). LLLT was able to increase the expression of myogenic and vascular growth factors and stimulate skeletal muscle regeneration in rats with chronic alcohol intake.