Efeitos do laser de baixa intensidade e da sida tuberculata na osteoartrite induzida por monoiodoacetato de sódio em joelho de ratos

Abstract

Knee Osteoarthritis (OA) is a chronic and degenerative disease, which causes pain, edema, movement limitations, with high occurency in the elderly, especially in developing countries. From a clinical point of view, OA treatment is based on the use of non-steroidal anti-inflammatory drugs and corticosteroids, which may or may not be associated with physiotherapeutic treatment; however, the use of these drugs may cause significant adverse effects. In this context, the use of Low Intensity Laser Therapy (LILT) and medicinal plants, such as Sida tuberculata, for the treatment of OA may be a promising alternative as therapy. Thus, this research investigated the effects of LILT, S. tuberculata, and the association of both, in the model of OA induced by monosodium iodoacetate (MIA) in the knee of rats, through the evaluation of biochemical and inflammatory parameters. Initially, different doses of MIA were studied for the induction of knee OA. The results indicated that the higher dose of MIA studied (1.5mg) caused increased oxidative stress damage and decreased antioxidant defense, both in the focus of the lesion and in distant sites. In addition, it induced an inflammatory process and lesions in the articular cartilage similar to those found in human OA. Once the most effective dose of MIA was established, the effects of LILT on knee OA were analyzed, in which there was a reduction in the levels of oxidative stress markers and an increase in antioxidant activity, both at the site of the lesions and in distant sites, suggesting a local effect with systemic consequences or a possible systemic effect. The laser treatment also attenuated the inflammatory process by relieving pain, reducing edema and neutrophil activity in the knee. Subsequently, the effects of S. tuberculata infusion on OA were analyzed. The infusion promoted a decrease in oxidative stress markers on blood serum, lower hypersensitivity, decrease neutrophil activity in intra-articular lavage and an increase activity in blood serum. Additional analyzes found low levels of S. tuberculata toxicity in blood serum, liver and kidney samples. Finally, the efficacy of both treatments and their association in knee OA was investigated. The results demonstrated that the combination of therapies did not produce the expected effect, although both reduced the markers of inflammation and oxidative stress. On the other hand, the application of Laser therapy presented a statistically significant reduction of the biochemical and inflammatory markers related to OA, in detriment to the treatment with S. tuberculata, Thus, Laser has showed to be an extremely promising therapy for the treatment of this degeneration. In this way, additional investigations, analyzing other effects of Laser and S. tuberculata and deepening the comprehension of their mechanisms of action, can further advance the frontier of knowledge regarding the inflammatory and osteoarthritic processes.