Comparative analysis of two low-level laser doses on the expression of inflammatory mediators and on neutrophils and macrophages in acute joint inflammation

Author(s)

dos Santos, Solange Almeida ^[1] ; Araruna Alves, Ana Carolina ^[2] ; Pinto Leal-Junior, Ernesto Cesar ^{[2, 3]} ; Albertini, Regiane ^{[2, 3]} ; Vieira, Rodolfo de Paula ^{[2, 4]} ; Ligeiro, Ana Paula ^[3] ; Silva Junior, Jose Antonio ^[4] ; Camillo de Carvalho, Paulo de Tarso ^{[2, 3]}

Affiliation

^[1] Univ Nove Julho UNINOVE, Dept Phys Therapy, Sao Paulo - Brazil

^[2] Univ Nove Julho UNINOVE, Postgrad Program Rehabil Sci, BR-01504001 Sao Paulo - Brazil

^[3] Univ Nove Julho UNINOVE, Postgrad Program Biophoton Appl Hlth Sci, Sao Paulo - Brazil

^[4] Univ Nove Julho UNINOVE, Postgrad Program Med, Sao Paulo - Brazil

• Document type: Journal article
• Source: Lasers in Medical Science; v. 29, n. 3, p. 1051-1058, MAY 2014.
• Web of Science Citations: 30

Abstract

Synovial membrane inflammation plays an important role in osteoarthritis (OA) pathophysiology. The synovial tissue of patients with initial OA is characterized by mononuclear cell infiltration and the production of pro-inflammatory cytokines and other mediators of joint injury. The study aims to evaluate the effect of low-level laser therapy (LLLT) at doses of 2 and 4 J on joint inflammation in rats induced by papain through histopathological analysis, differential counts of inflammatory cells; gene expression of IL-1 beta, IL-6, and IL-10; and TNF-alpha protein expression. Male Wistar rats (20) were randomly divided (5 animals each) into a negative control group, an inflammation injury positive control group, a 2-J LLLT group subjected to injury and treated with 2 J of LLLT, and a 4-J LLLT group subjected to injury and treated with 4 J of LLLT. The animals were subjected to joint inflammation (4 % papain solution) and treated with LLLT. On the day of euthanasia, articular lavage was collected and centrifuged. The supernatant was analyzed for TNF-alpha protein expression by ELISA and IL-1 beta, IL-6, and IL-10 mRNA by RT-PCR. The joint tissue was also examined histologically. ANOVA with Tukey's post hoc test was used for comparisons. All data were expressed as means +/- S.D. (p < 0.05). Both laser modalities were efficient in reducing cellular inflammation and decreasing the expression of IL-1 beta and IL-6. However, the 2-J treatment led to more reduction in TNF-alpha than the 4-J treatment. A single application of LLLT with 2 J was more efficient in modulating inflammatory mediators and inflammatory cells. (AU)

• FAPESP's process: 10/52404-0 - Low-level laser therapy in skeletal muscle fatigue and post-exercise recovery: Optimal parameters and effects in long-duration exercise
• Grantee: Ernesto Cesar Pinto Leal Junior
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 11/04834-8 - Effects of low level laser radiation with wavelengths of 660nm and 808nm on cartilage injury
• Grantee: Ana Carolina Araruna Alves
• Support Opportunities: Scholarships in Brazil - Master