Effect of Low Level Laser Therapy on the expression of inflammatory mediators and on neutrophils and macrophages in acute joint inflammation

Ana Carolina A Alves, Rodolfo P Vieira, Ernesto Cesar P Leal-Junior, Solange A dos Santos, Ana Paula Ligeiro, Regiane Albertini, José Antonio S Junior, and Paulo de Tarso C de Carvalho
Arthritis Research & Therapy 2013, 15:R116 doi:10.1186/ar4296


Inflammation of the synovial membrane plays an important role in the pathophysiology of osteoarthritis (OA). The synovial tissue of patients with initial OA is characterized by infiltration of mononuclear cells and production of pro-inflammatory cytokines and other mediators of joint injury. Objective: To evaluate the effect of low-level laser therapy (LLLT) operating at 50 mW and 100 mW on joint inflammation in rats induced by papain, through histopathological analysis, differential counts of inflammatory cells (macrophages and neutrophils), as well as gene expression of interleukin 1-beta and 6 (IL-1ß and IL-6), and protein expression of tumor necrosis factor alpha