Low-level laser therapy in collagenase-induced Achilles tendinitis in rats: analyses of biochemical and biomechanical aspects.
NSAIDs are widely prescribed and used over the years to treat tendon injuries despite its well-known long-term side effects. In the last years several animal and human trials have shown that low-level laser therapy (LLLT) presents modulatory effects on inflammatory markers, however the mechanisms involved are not fully understood. The aim of this study was to evaluate the short-term effects of LLLT or sodium diclofenac treatments on biochemical markers and biomechanical properties of inflamed Achilles tendons. Wistar rats Achilles tendons (n = 6/group) were injected with saline (control) or collagenase at peritendinous area of Achilles tendons. After 1 h animals were treated with two different doses of LLLT (810 nm, 1 and 3 J) at the sites of the injections, or with intramuscular sodium diclofenac. Regarding biochemical analyses, LLLT significantly decreased (p < 0.05) COX-2, TNF-α, MMP-3, MMP-9, and MMP-13 gene expression, as well as prostaglandin E(2) (PGE(2) ) production when compared to collagenase group. Interestingly, diclofenac treatment only decreased PGE(2) levels. Biomechanical properties were preserved in the laser-treated groups when compared to collagenase and diclofenac groups. We conclude that LLLT was able to reduce tendon inflammation and to preserve tendon resistance and elasticity.
Laboratory of Pharmacology and Experimental Therapeutics, Department of Pharmacology, Institute of Biomedical Sciences, University of Sao Paulo, Av. Prof. Lineu Prestes, 1524, Butantan, São Paulo 05508-900, SP, Brazil.
Rodrigo Labat
RL
Marcos
Ernesto Cesar Pinto
EC
Leal-Junior
Gilles
G
Arnold
Vincent
V
Magnenet
Rachid
R
Rahouadj
Xiong
X
Wang
Frank
F
Demeurie
Jacques
J
Magdalou
Maria Helena Catelli
MH
de Carvalho
Rodrigo Álvaro Brandão
RÁ
Lopes-Martins
D000125:Achilles Tendon / Q000473:pathology*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001671:Biochemistry / Q000379:methods; D001696:Biomechanical Phenomena; D017364:Collagenases / Q000737:chemistry / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D004008:Diclofenac / Q000494:pharmacology; D015232:Dinoprostone / Q000378:metabolism; D007249:Inflammation; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D020782:Matrix Metalloproteinases / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D052256:Tendinopathy / Q000209:etiology / Q000532:radiotherapy*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D000894:Anti-Inflammatory Agents, Non-Steroidal; D014409:Tumor Necrosis Factor-alpha; D004008:Diclofenac; D051546:Cyclooxygenase 2; D017364:Collagenases; D020782:Matrix Metalloproteinases; D015232:Dinoprostone