THE EFFECT OF CRYOTHERAPY IN THE NOCICEPTION, INFLAMMATORY CYTOKINES AND NEUROMUSCULAR SIGNALING PATHWAYS OF MICE WITH KNEE ARTHRITIS

Abstract

Arthritis is an inflammatory joint disorder that can take several forms such as osteoarthritis, rheumatoid arthritis, gout, etc. When it affects the knee, can be characterized by increasing mediators in inflammatory synovial fluid, pain, swelling, thickening joint, weakness and atrophy of the quadriceps muscle. Cryotherapy is a non-pharmacological intervention widely used to control pain and inflammation in musculoskeletal disorders and is also used in knee arthritis, associated with other treatments. However, there is a lack of scientific evidence regarding the effects of cryotherapy in joint inflammation. The aim of this study is to evaluate the effect of cryotherapy in induced arthritis in the knee of mice. We will evaluate the following: nociception articular levels of pro cytokines (IL-6, IL-1², TNF-±, IL-17) and anti-inflammatory (IL-4, IL-10) in synovial fluid and possible changes morphological and molecular muscle fibers in neuromuscular junctions and in the quadriceps. Four groups will be analyzed (n = 10 per group) from C57BL / 6 mice (20-25g): Control (without intervention); Cryotherapy (Cryo); Right knee mBSA-induced arthritis antigen with intra-articular injection (arthritis); Cryotherapy and arthritis (arthritis + Cryo). Five daily sessions of cryotherapy (bag with crushed ice, 20 min) will be held in the affected limb every 2 hours, between 8 and 18h, involving the entire leg (the femoral lame joint until tibio-tarsal joint ). The first session will be held on day 21, immediately after intraarticular injection and consecutively over five sessions in 22 days. At 23 days will be assessed nociception articulate and then the animals will be euthanized to collect synovial fluid and quadriceps muscle. Statistical analysis will be performed by analysis of variance one-way ANOVA followed by multiple comparisons by Tukey test.