Effects of Low-level Laser Therapy on Muscle Repair in Rats with Chronic Alcohol Intake

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

Alcoholic neuropathy associated with chronic alcohol intake

Alcoholic neuropathy (AN), a debilitating condition that mainly affects chronic alcohol drinkers, is thought to cause lesions in the peripheral nervous system leading to sensory, autonomic, and motor dysfunctions. Despite many studies, the pathogenesis of these lesions is still not completely understood. We investigated few aspects on the development of alcohol-induced peripheral neuropathy, by assessing sensory, motor and autonomic functions, as well as stereological analysis of axonal fibers and myelin sheath of the sciatic nerve. Twelve male Wistar rats were divided into Control group and Alcohol group that was submitted to Two Bottle-Choice Paradigm of intermittent and voluntary alcohol solution intake (20%; v/v) during eight weeks. At the end of treatment, three different sensorium-motor tests were applied - Tactile Sensitivity, Thermal Sensitivity, and Functional Observational Battery (FOB). Quantitative morphometric analysis of sciatic nerve structures was performed by stereological method. Alcohol concentration in the blood was measured to analyze possible correlation between availability of alcohol in the blood and the magnitude of the peripheral nerve lesion. Our data showed a peripheral effect of chronic alcohol intake associated with hyperalgesia and a process of demyelination with a strong correlation with alcohol consumption. This process was associated with increased tactile sensitivity, with behavioral reflexes such as locomotor hyperactivity, changes in gait and balance, and autonomic reflexes such as piloerection