Effects of 660 and 780 nm Low-Level Laser Therapy on Neuromuscular Recovery After Crush Injury in Rat Sciatic Nerve

Autor(es)

Gigo-Benato, Davilene ^[1] ; Russo, Thiago Luiz ^[2] ; Tanaka, Erika Harumi ^[1] ; Assis, Livia ^[1] ; Salvini, Tania Fatima ^[2] ; Parizotto, Nivaldo Antonio ^[1]

Afiliação do(s) autor(es)

^[1] Fed Univ Sao Carlos UFSCar, Phys Therapy Dept, Thermophototherapy Unit, 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

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Surgery and Medicine; v. 42, n. 9, p. 673-682, NOV 2010.
• Citações Web of Science: 46

Resumo

Background and Objective: Post-traumatic nerve repair is still a challenge for rehabilitation. It is particularly important to develop clinical protocols to enhance nerve regeneration. The present study investigated the effects of 660 and 780 nm low-level laser therapy (LLLT) using different energy densities (10, 60, and 120 J/cm(2)) on neuromuscular and functional recovery as well as on matrix metalloproteinase(MMP) activity after crush injury in rat sciatic nerve. Materials and Methods: Rats received transcutaneous LLLT irradiation at the lesion site for 10 consecutive days post-injury and were sacrificed 28 days after injury. Both the sciatic nerve and tibialis anterior muscles were analyzed. Nerve analyses consisted of histology (light microscopy) and measurements of myelin, axon, and nerve fiber cross-sectional area (CSA). S-100 labeling was used to identify myelin sheath and Schwann cells. Muscle fiber CSA and zymography were carried out to assess the degree of muscle atrophy and MMP activity, respectively. Statistical significance was set at 5% (P <= 0.05). Results: Six hundred sixty nanometer LLLT either using 10 or 60 J/cm(2) restored muscle fiber, myelin and nerve fiber CSA compared to the normal group (N). Furthermore, it increased MMP-2 activity in nerve and decreased MMP-2 activity in muscle and MMP-9 activity in nerve. In contrast, 780 nm LLLT using 10 J/cm(2) decreased MMP-9 activity in nerve compared to the crush group (CR) and N; it also restored normal levels of myelin and nerve fiber CSA. Both 60 and 120 J/cm(2) decreased MMP-2 activity in muscle compared to CR and N. 780 nm did not prevent muscle fiber atrophy. Functional recovery in the irradiated groups did not differ from the non-irradiated CR. Conclusion: Data suggest that 660 nm LLLT with low (10 J/cm(2)) or moderate (60 J/cm(2)) energy densities is able to accelerate neuromuscular recovery after nerve crush injury in rats. Lasers Surg. Med. 42:673-682, 2010. (C) 2010 Wiley-Liss, Inc. (AU)

• Processo FAPESP: 06/52931-4 - Analise da regeneracao do nervo isquiatico de ratos em lesoes moderadas e graves sob acao do laser de baixa intensidade.
• Beneficiário: Davilene Gigo Benato
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 08/03499-8 - Efeito da ruptura do ligamento cruzado anterior sobre a morfologia, expressão de genes e proteínas associados à atrofia no músculo quadríceps femoral de ratos
• Beneficiário: Gabriel Borges Delfino
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto