Low-level laser therapy (LLLT; 780 nm) acts differently on mRNA expression of anti- and pro-inflammatory mediators in an experimental model of collagenase-induced tendinitis in rat

Autor(es)

Pires, Debora ^[1] ; Xavier, Murilo ^[2] ; Araujo, Tiago ^[3] ; Silva, Jr., Jose Antnio ^[3] ; Aimbire, Flavio ^[2] ; Albertini, Regiane ^{[2, 3]}

Afiliação do(s) autor(es)

^[1] Inst Res & Dev, BR-12244000 Sao Jose Dos Campos, SP - Brazil

^[2] Univ Camilo Castelo Branco UNICASTELO, Inst Biomed Engn, BR-12247000 Sao Jose Dos Campos, SP - Brazil

^[3] UNINOVE, Dept Rehabil Sci, BR-235 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Medical Science; v. 26, n. 1, p. 85-94, JAN 2011.
• Citações Web of Science: 76

Resumo

Low-level laser therapy (LLLT) has been found to produce anti-inflammatory effects in a variety of disorders. Tendinopathies are directly related to unbalance in expression of pro- and anti-inflammatory cytokines which are responsible by degeneration process of tendinocytes. In the current study, we decided to investigate if LLLT could reduce mRNA expression for TNF-alpha, IL-1 beta, IL-6, TGF-beta cytokines, and COX-2 enzyme. Forty-two male Wistar rats were divided randomly in seven groups, and tendinitis was induced with a collagenase intratendinea injection. The mRNA expression was evaluated by real-time PCR in 7th and 14th days after tendinitis. LLLT irradiation with wavelength of 780 nm required for 75 s with a dose of 7.7 J/cm(2) was administered in distinct moments: 12 h and 7 days post tendinitis. At the 12 h after tendinitis, the animals were irradiated once in intercalate days until the 7th or 14th day in and them the animals were killed, respectively. In other series, 7 days after tendinitis, the animals were irradiated once in intercalated days until the 14th day and then the animals were killed. LLLT in both acute and chronic phases decreased IL-6, COX-2, and TGF-beta expression after tendinitis, respectively, when compared to tendinitis groups: IL-6, COX-2, and TGF-beta. The LLLT not altered IL-1 beta expression in any time, but reduced the TNF-alpha expression; however, only at chronic phase. We conclude that LLLT administered with this protocol reduces one of features of tendinopathies that is mRNA expression for pro-inflammatory mediators. (AU)

• Processo FAPESP: 07/02596-7 - Analise do mecanismo de acao da terapia laser de baixa potencia em modelo experimental de inflamacao cronica.
• Beneficiário: Regiane Albertini
• Modalidade de apoio: Auxílio à Pesquisa - Regular