Efeito do treinamento físico resistido associado ao laser de baixa intensidade em modelo experimental de osteoartrite de joelho: avaliação hemodinâmica e efeitos locais

Abstract

Osteoarthritis (OA) is a degenerative inflammatory disease of the joint, and the main symp-toms are decreased functional capacity, pain and consequently worsening the quality of life of the affected individual. In addition, the current pharmacological treatments for OA have as one of the side effects unwanted gastrointestinal changes. Therefore, the objective of this study was to evaluate the effect of two non-pharmacological therapies: resistance training (RT) associated with the low intensity laser (LBI) in an experimental model of OA in rats at hemodynamic and lesion site evaluation. For this purpose, 40 male Wistar rats weighing be-tween 200 and 280 g and resistance training were divided into five groups: the control group (C); Osteoarthritis (OA); Osteo-arthritis + LBI (OL); And trained: osteoarthritis + TR (OR); And OA + TR + LBI (ORL). OA was induced by injection of 20 μl (10μ of 4% papain and 0.03M cysteine) into the virtual intra-articular space of the right knee. The OR and ORL groups were submitted to a LBI-associated ladder resistance training protocol (660 nm, 5 mW, 2.5 J / cm 2, 20 s, A = 0.04 cm 2) for 8 weeks. The results showed that the OR and ORL groups presented lower body weight at the end of the treatment protocol and improved func-tional capacity assessed through the Maximum stress test in comparison to the sedentary groups. The hemodynamic evaluation showed that blood pressure did not reveal a statistically significant difference between the studied groups and the heart rate also evaluated by hemo-dynamic recording was decreased in the ORL group, which indicates cardiovascular protec-tion. The leukocyte influence showed increased cells in the OA group, which was not ob-served in the OR and ORL groups. The histological analysis of the synovial membrane showed the protective effect of LBI associated with TR in relation to fibrosis, reduction of intense inflammatory process and edema. The results of this work demonstrated that the asso-ciation of the low-intensity laser with resistance training proved to be efficient as a non-pharmacological treatment of osteoarthritis, reducing the systemic and local involvement of the disease.