Effects of photobiomodulation therapy on functional recovery, angiogenesis and redox status in denervated muscle of rats / Efeitos da terapia de fotobiomodulação na recuperação funcional, na angiogênese e no estado redox em músculo desnervado de ratos

ABSTRACT Objective: To evaluate the effects of photobiomodulation therapy in redox status, angiogenesis marker - vascular endothelial growth factor - and in the functional recovery in denervated muscle. Methods: A total of 32 female Wistar rats underwent a crush injury and were randomly divided into four groups: Light Emitting Diode Group 2 and Control Group 2 (muscle collected 2 days after injury), and Light Emitting Diode Group 21 and Control Group 21 (muscle collected 21 days afterinjury). Light Emitting Diode Group 2 and Light Emitting Diode Group 21 received two and ten light emitting diode applications (630±20nm, 9J/cm2, 300mW), respectively, and the Control Group 2 and Control Group 21 did not receive any treatment. The function was evaluated by grasping test at four moments (pre-injury, 2, 10 and 21 post-injury days). The flexor digitorum muscle was collected for analysis of immunolocalization of vascular endothelial growth factor and redox parameters. Results: Functional improvement was observed at the second and tenth post-injury day in treated groups compared to control (p<0.005). The muscle tissue of treated groups presented higher immunohistochemical expression of vascular endothelial growth factor. Photobiomodulation therapy decreased the oxidative damage to lipid in Light Emitting Diode Group 2 compared to Control Group 2 (p=0.023) in the denervated muscle. Conclusion: Photobiomodulation therapy accelerated the functional recovery, increased angiogenesis and reduced lipid peroxidation in the denervated muscle at 2 days after injury.

RESUMO Objetivo: Avaliar os efeitos da terapia de fotobiomodulação no estado redox, no marcador de angiogênese - fator de crescimento endotelial vascular - e na recuperação funcional do músculo desnervado. Métodos: Um total de 32 ratas Wistar foi submetido a uma lesão por esmagamento e dividido aleatoriamente em quatro grupos: Grupo Diodo Emissor de Luz 2 e Grupo Controle 2 (músculo coletado 2 dias após a lesão), além do Grupo Diodo Emissor de Luz 21 e do Grupo Controle 21 (músculo coletado 21 dias após a lesão). Grupo Diodo Emissor de Luz 2 e Grupo Diodo Emissor de Luz 21 receberam duas e dez aplicações de diodo emissor de luz (630±20nm, 9J/cm2e 300mW), respectivamente, e Grupo Controle 2 e Grupo Controle 21 não receberam tratamento. A função foi avaliada pelo teste de preensão em quatro momentos (pré-lesão, 2, 10 e 21 dias após a lesão). O músculo flexor dos dedos foi coletado para análise dos parâmetros redox e da imunolocalização do fator de crescimento endotelial vascular. Resultados: Houve melhora funcional no segundo e décimo dia pós-lesão nos grupos tratados em comparação aos controles (p<0,005). O tecido muscular dos grupos tratados apresentou maior expressão imuno-histoquímica do fator de crescimento endotelial vascular. A terapia de fotobiomodulação diminuiu o dano oxidativo aos lipídeos no Grupo Diodo Emissor de Luz 2 comparado ao Grupo Controle 2 (p=0,023) no músculo desnervado. Conclusão: A terapia de fotobiomodulação acelerou a recuperação funcional, aumentou a angiogênese e reduziu a peroxidação lipídica no músculo desnervado 2 dias após a lesão.

Essential oil from Ageratum fastigiatum reduces expression of the pro-inflammatory cytokine tumor necrosis factor-alpha in peripheral blood leukocytes subjected to in vitro stimulation with phorbol myristate acetate

Abstract Ageratum fastigiatum (Gardner) R.M. King & H. Rob., a member of the Asteraceae family popularly known in Brazil as "matapasto", is indicated in folk medicine as anti-inflammatory and analgesic. Despite its popular use, little is known about its potential effect on the parameters involved in an inflammatory response. The objective of this study was to characterize the chemical composition of the essential oil from A. fastigiatum and to evaluate the frequency of tumor necrosis factor alpha and interferon gamma producing cells in peripheral blood lymphocytes stimulated with phorbol myristate acetate in the presence of essential oil from A. fastigiatum. Non-toxic concentrations of essential oil from A. fastigiatum were evaluated in cultures of peripheral blood leucocytes using the trypan blue exclusion assay by flow cytometry. GC–MS analysis revealed that the prevalent compounds identified in the essential oil from A. fastigiatum sample were α-pinene, limonene, trans-caryophyllene, α-humulene, caryophyllene oxide, 1,2-humulene-epoxide, 1,6-humulanodien-3-ol, and α-cadinol. Results showed that exposure to essential oil from A. fastigiatum at concentrations of 0.5 × 10−2 and 1 × 10−2 µl/ml caused no alterations in leukocyte viability as compared to the control group. Both concentrations lowered the percentage of tumor necrosis factor alpha (+)-lymphocytes and neutrophils. There were no changes in the percentage of lymphocytes positive for the interferon gamma cytokine. Our results suggest that part of the anti-inflammatory activity attributed to A. fastigiatum may be due to the effect of some of its components in decreasing the number of cells that produce the pro-inflammatory cytokine tumor necrosis factor alpha.