Effect of Low-Level Laser Therapy (LLLT) on Acute Neural Recovery and Inflammation-Related Gene Expression After Crush Injury in Rat Sciatic Nerve

Autor(es)

Alcantara, Carolina C. ^[1] ; Gigo-Benato, Davilene ^{[2, 1]} ; Salvini, Tania F. ^[2] ; Oliveira, Alexandre L. R. ^[3] ; Anders, Juanita J. ^[4] ; Russo, Thiago L. ^[1]

Afiliação do(s) autor(es)

^[1] Fed Univ Sao Carlos UFSCar, Phys Therapy Dept, Lab Neurol Physiotherapy Res, BR-13565905 Sao Carlos, SP - Brazil

^[2] Fed Univ Sao Carlos UFSCar, Phys Therapy Dept, Skeletal Muscle Plast Unit, BR-13565905 Sao Carlos, SP - Brazil

^[3] Univ Campinas UNICAMP, Dept Anat Cell Biol Physiol & Biophys, Inst Biol, BR-13083865 Campinas, SP - Brazil

^[4] Uniformed Serv Univ Hlth Sci, Dept Anat Physiol & Genet, Bethesda, MD 20814 - USA

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Surgery and Medicine; v. 45, n. 4, p. 246-252, APR 2013.
• Citações Web of Science: 23

Resumo

Background and Objectives Peripheral nerve function can be debilitated by different kinds of injury. Low-level laser therapy (LLLT) has been used successfully during rehabilitation to stimulate recovery. The aim of this study was to evaluate the effects of LLLT (660nm, 60J/cm2, 40mW/cm2) on acute sciatic nerve injury. Materials and Methods Thirty Wistar male rats were divided into three groups: (1) Normal, intact nerves; (2) I3d, crushed nerves evaluated on Day-3 post-injury; (3) I+L3d, crushed nerves submitted to two sessions of LLLT and investigated at 3 days post-injury. Sciatic nerves were removed and processed for gene expression analysis (real-time PCR) of the pro-inflammatory factors TWEAK, Fn14 and TNF- and extracellular matrix remodeling and axonal growth markers, such as TIMP-1, MMP-2, and MMP-9. Zymography was used to determine levels of MMP-2 and MMP-9 activity and Western blotting was used to evaluate TNF- protein content. ShapiroWilk and Levene's tests were applied to evaluate data normality and homogeneity, respectively. One-way ANOVA followed by Tukey test was used for statistical analysis with a significance level set at 5%. Results An increase in TNF- protein level was found in I+L3 compared to Normal and I3d (P<0.05). Zymography showed an increase in proMMP-9 activity, in both I3d and I+L3d groups (P<0.05). The increase was more evident in I+L3d (P=0.02 compared to I3d). Active-MMP-9 isoform activity was increased in I+L3d compared to Normal and I3d groups (P<0.05). Furthermore, the activity of active-MMP-2 isoform was increased in I3d and I+L3 (P<0.05). An increase in TIMP-1 expression was observed in both I3d and I+L3d groups (P<0.05). Conclusions The current study showed that LLLT increased MMPs activity, mainly MMP-9, and TNF- protein level during the acute phase of nerve injury, modulating inflammation. Based on these results, it is recommended that LLLT should be started as soon as possible after peripheral nerve injury. Lasers Surg. Med. 9999:XXXX, 2013. (c) 2013 Wiley Periodicals, Inc. (AU)

• Processo FAPESP: 10/11795-6 - Avaliação da ação do laser de baixa potência sobre a regeneração neuromuscular em ratos com axonotmese
• Beneficiário: Thiago Luiz de Russo
• Modalidade de apoio: Auxílio à Pesquisa - Regular