Jefferson Potiguara de Moraes, Luis Ulisses Signori, Rodrigo Pereira Martins, Bianca Vedoin Copês Rambo, Gustavo Orione Puntel, Manuela Bianchin Marcuzzo, Darcieli Lima Ramos, Ricardo Evandro Mendes, Jaqueline Santana da Rosa, Ingrid Wentzel Souza, Thiago Durand Mussoi, Camila Franco, Virgínia Cielo Rech

SUMMARY
Background. Quercetin has therapeutic potential in the recovery of musculoskeletal injuries, but orally, this polyphenol presents poor absorption because of its poor water solubility and structural instability. However, its penetration through the skin can be enhanced by quercetin-loaded nanostructured lipid carriers (NLC-Q), even more, when associated with pulsed therapeutic ultrasound (PUT).
Objective. To evaluate the effect of sonophoresis PTU with a gel NLC-Q on biochemical parameters after traumatic muscle injury of the gastrocnemius muscle.
Methods. Forty male Wistar rats were homogeneously divided into five groups: Control; Lesion (no treatment); PTU treated lesion; NLC-Q gel treated lesion and Sonophoresis (PTU with NLC-Q gel) treated lesion. The gastrocnemius muscle was lesioned by mechanical crushing and treatments began 24h after the injury. Interventions were performed at intervals of 12h, making a total of 5 sessions lasting 5 min each. The 1 MHz PUT (0.1 W/cm2SATA, pulsed wave: 20%); NLC-Q gel was spread over the lesion area and sonophoresis used PTU with NLC-Q gel. Serum and muscle creatine kinase (CK) concentrations and muscle oxidative stress (concentration of reactive oxygen species [ROS], lipid peroxidation, protein carbonyls, and the activities of SOD and Catalase enzymes) were evaluated 96h after the lesion.
Results. Blood CK increased only in the untreated Lesion group. Sonophoresis reduced SOD activity, concentration of ROS, lipid peroxidation, and protein oxidation in relation to the Lesion group (p < 0.05), but it was similar to the other interventions.
Conclusions. Sonophoresis, PUT, and NLC-Q Gel contributed to the repair of muscle damage and reduced oxidative stress parameter
KEY WORDS
Inflammation; solid lipid nanoparticles (SLN); sonophoresis; skeletal muscle; ultrasonic therapy.