The Role and Mechanism of Aspirin Combined with Rehabilitation Training in the Repair of Sciatic Nerve Injury and the Changes in the Schwannocytus (Schwann Cells) in Rats / Rol y Mecanismo de la Aspirina Combinados con Entrenamiento de Rehabilitación en la Reparación de la Lesión del Nervio Ciático y los Cambios en los Schwannocitos (Células de Schwann) en Ratas

SUMMARY: This study investigated the role and mechanism of aspirin combined with rehabilitation training in the nerve injury repair and Schwann cell changes in rats with sciatic nerve injury. Totally, 120 male healthy SD rats were randomly divided into sham, model, aspirin, and aspirin + rehabilitation groups, with 30 rats in each group. The sciatic nerve function index (SFI), photothermal pain tolerance threshold and inclined plane test results at 4, 6, and 8 weeks after operation were compared. The distance of sensory nerve regeneration and the expression of S100B protein in Schwann cells were analyzed. Compared with the sham group, the SFI of the model, aspirin, and aspirin+rehabilitation groups were significantly lower at 4, 6, and 8 weeks after operation. However, the aspirin and aspirin+rehabilitation groups had significantly higher SFI than the model group. The SFI at 6 and 8 weeks after operation was higher in the aspirin+rehabilitation group than that in the aspirin group (P<0.05). The photothermal pain tolerance threshold of the sham, aspirin, and aspirin+rehabilitation groups were significantly higher than those of the model group at 4, 6, and 8 weeks after operation (P<0.05). The inclination angles of the model, aspirin, and aspirin+rehabilitation groups were significantly lower than those of the sham group at 4, 6, and 8 weeks after operation, and the inclination angle of the aspirin+rehabilitation group was significantly higher than that of the model and aspirin groups (P<0.05). The sensory nerve regeneration distance in aspirin and aspirin+rehabilitation groups was higher than that in the sham and model groups (P<0.05). The expression of S100B protein in the aspirin and aspirin+rehabilitation groups was higher than that in the model group (P<0.05). Aspirin combined with rehabilitation training can promote the functional recovery of sciatic nerve injury, and the mechanism may be related to the increase of the expression of S100B protein in Schwann cells.

En este estudio se investigó el papel y el mecanismo que desempeña la aspirina combinada, con el entrenamiento de rehabilitación en la reparación de lesiones nerviosas y los cambios en los schwannocitos en ratas con lesiones en el nervio ciático. En total, 120 ratas SD macho sanas se dividieron aleatoriamente en cuatro grupos de 30 ratas en cada uno: simulación, modelo, aspirina y aspirina + rehabilitación. Se compararon el índice de función del nervio ciático (SFI), el umbral de tolerancia al dolor fototérmico y los resultados de la prueba del plano inclinado a las 4, 6 y 8 semanas después de la operación. Se analizó la distancia de regeneración del nervio sensorial y la expresión de la proteína S100B en los schwannocitos. En comparación con el grupo simulado, el SFI de los grupos modelo, aspirina y aspirina+rehabilitación fue significativamente menor a las 4, 6 y 8 semanas después de la operación. Sin embargo, los grupos de aspirina y aspirina + rehabilitación tuvieron un SFI significativamente más alto que el grupo modelo. El SFI a las 6 y 8 semanas después de la operación fue mayor en el grupo de aspirina + rehabilitación que en el grupo de aspirina (P<0,05). El umbral de tolerancia al dolor fototérmico de los grupos simulado, aspirina y aspirina+rehabilitación fue significativamente mayor que el del grupo modelo a las 4, 6 y 8 semanas después de la operación (P<0,05). Los ángulos de inclinación de los grupos modelo, aspirina y aspirina+rehabilitación fueron significativamente menores que los del grupo simulado a las 4, 6 y 8 semanas después de la operación, y el ángulo de inclinación del grupo aspirina+rehabilitación fue significativamente mayor que el de los grupos modelo y aspirina (P<0.05). La distancia de regeneración del nervio sensorial en los grupos de aspirina y aspirina+rehabilitación fue mayor que en los grupos simulado y modelo (P<0,05). La expresión de la proteína S100B en los grupos de aspirina y aspirina+rehabilitación fue mayor que en el grupo modelo (P<0,05). La aspirina combinada con el entrenamiento de rehabilitación puede promover la recuperación funcional de la lesión del nervio ciático, y el mecanismo puede estar relacionado con el aumento de la expresión de la proteína S100B en los schwannocitos.

Action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after nerve injury / Ação da vanilina (Vanilla planifolia) sobre a morfologia dos músculos tibial anterior e sóleo após lesão nervosa

ABSTRACT Objective To evaluate the action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after peripheral nerve injury. Methods Wistar rats were divided into four groups, with seven animals each: Control Group, Vanillin Group, Injury Group, and Injury + Vanillin Group. The Injury Group and the Injury + Vanillin Group animals were submitted to nerve injury by compression of the sciatic nerve; the Vanillin Group and Injury + Vanillin Group, were treated daily with oral doses of vanillin (150mg/kg) from the 3rd to the 21st day after induction of nerve injury. At the end of the experiment, the tibialis anterior and soleus muscles were dissected and processed for light microscopy and submitted to morphological analysis. Results The nerve compression promoted morphological changes, typical of denervation, and the treatment with vanillin was responsible for different responses in the studied muscles. For the tibialis anterior, there was an increase in the number of satellite cells, central nuclei and fiber atrophy, as well as fascicular disorganization. In the soleus, only increased vascularization was observed, with no exacerbation of the morphological alterations in the fibers. Conclusion The treatment with vanillin promoted increase in intramuscular vascularization for the muscles studied, with pro-inflammatory potential for tibialis anterior, but not for soleus muscle.

RESUMO Objetivo Avaliar a ação da vanilina (Vanilla planifolia) sobre a morfologia dos músculos tibial anterior e sóleo após lesão nervosa periférica. Métodos Ratos Wistar foram divididos em quatro grupos, com sete animais cada, sendo Grupo Controle, Grupo Vanilina, Grupo Lesão e Grupo Lesão + Vanilina. Os animais dos Grupos Lesão e Grupo Lesão + Vanilina foram submetidos à lesão nervosa por meio da compressão do nervo isquiático, e os Grupos Vanilina e Grupo Lesão + Vanilina foram tratados diariamente com doses orais de vanilina (150mg/kg) do 3o ao 21o dia após a indução da lesão nervosa. Ao término do experimento, os músculos tibial anterior e sóleo foram dissecados e seguiram o processamento de rotina em microscopia de luz, para posterior análise morfológica. Resultados A compressão nervosa promoveu alterações morfológicas características de denervação, sendo que o tratamento com vanilina foi responsável por respostas distintas nos músculos estudados. Para o tibial anterior, houve aumento do número de células satélites, núcleos centrais e atrofia das fibras, bem como desorganização fascicular. Já no sóleo, houve apenas aumento da vascularização, sem exacerbação das alterações morfológicas nas fibras. Conclusão O tratamento com vanilina promoveu o aumento da vascularização intramuscular para os músculos estudados, com potencial pró-inflamatório para o tibial anterior, o que não ocorreu no músculo sóleo.

Ação do exercício de subida em escada com sobrecarga na morfologia do músculo tibial anterior de ratos Wistars após axonotmese / Action of the climbing ladder exercise with overload in the morphology of the anterior tibial muscle of wistars rats after axonotmesis

Objetivo: avaliar histomorfometrica e morfologicamente o músculo tibial anterior de ratos submetidos à axonotmese e tratados com exercício. Métodos: foram randomizados 28 ratos Wistar nos grupos controle (GC), exercício (GE), lesão (GL) e lesão+exercício (GLE). No terceiro dia após compressão, GE e GLE realizaram exercício de subida em escada, com duas séries de dez repetições. Após 21 dias, o músculo tibial anterior foi processado para microscopia de luz. Resultados: Na análise morfológica GC apresentou morfologia com aspecto característico, GE hipertrofia muscular, GL alterações morfológicas, como fibras polimórficas e núcleos centrais, e GLE aspecto semelhante ao controle, porém com algumas alterações. Na área de secção transversa e menor diâmetro das fibras GC e GE apresentaram valores maiores, o inverso da análise de vasos sanguíneos. Para o tecido conjuntivo, GE apresentou-se menor que o GL. Conclusão: O protocolo de exercício promoveu melhora nos aspectos histomorfológicos, mas não reverteu totalmente os efeitos deletérios. (AU)

Objective: to evaluate morphologically the tibialis anterior muscle of rats submitted to axonotmosis and treated with exercise. Methods: 28 Wistar rats were used in groups control (CG), exercise (GE), injury (GL) and injury + exercise (GLE). On the third day after compression, GE and GLE performed climb exercise staircase, with two sets of ten repetitions. After 21 days, the muscle was processed for light microscopy. Results: In the morphological analysis GC presented with morphology characteristic appearance, GE muscle hypertrophy, GL morphological changes like polymorphic fibers and central nucleo, and GLE look similar to the control, but with some changes morphological. In the cross-sectional area and smaller diameter of the GC and GE fiber showed higher values, inversed analysis of blood vessels. For the connective tissue, GE was lower than the GL. Conclusion: Summing up, the exercise promoted improvement in morphological aspects, but not totally reversed the deleterious effects of denervation. (AU)

Estimulação elétrica de alta voltagem em nervo ciático de ratos: estudo pelo IFC / High voltage pulsed current stimulation of the sciatic nerve in rats: analysis by the SFI

OBJETIVO: Analisar a eficiência do tratamento com a estimulação elétrica de alta voltagem (EEAV) em três diferentes locais, aplicada precocemente na regeneração do nervo ciático submetido à lesão por esmagamento, e avaliada através do índice funcional do ciático (IFC), em ratos. MÉTODO: Após o esmagamento, 57 ratos foram submetidos à EEAV catódica nos parâmetros: frequência de 50Hz, 100V de tensão, 20 minutos diários, 5 dias por semana. Os ratos foram divididos aleatoriamente em: grupo controle; grupo gânglio; grupo gânglio + músculo; grupo músculo e; grupo simulado. O IFC foi avaliado semanalmente durante sete semanas, partindo do pré-operatório até a 6ª semana pós-operatória. RESULTADOS: Em comparação ao grupo controle, os resultados mostraram desempenho significativamente superior do grupo gânglio nas três primeiras semanas, e do grupo gânglio + músculo na 3ª semana, enquanto o grupo músculo teve desempenho significativamente negativo na 4ª e 6ª semanas. CONCLUSÃO: a EEAV aplicada precocemente, foi positiva no tratamento da região da medula e gânglio da raiz nervosa do ciático com o eletrodo dispersivo na região lombar contralateral ou no músculo gastrocnêmio. Porém, proporcionou efeitos negativos no tratamento com eletrodo ativo no músculo gastrocnêmio e dispersivo na coxa contralateral. Nível de evidência II, Estudo prospectivo comparativo.

OBJECTIVE: To analyze the efficiency of high voltage pulsed current (HVPC) with early application in three different sites, in the regeneration of the sciatic nerve in rats submitted to crush injury, the sciatic functional index (SFI) was used to assess the functional recovery. METHODS: After crushing of the nerve, 57 animals were submitted to cathodal HVPC at frequency of 50Hz and voltage of 100V, 20 minutes per day, 5 days per week. The rats were divided into five groups: control group; ganglion group; ganglion + muscle group; muscle group; and sham group. The SFI was determined weekly for seven weeks, from the preoperative period to the 6th postoperative week. RESULTS: Compared with the control group, the results showed a significantly better performance of group 2 for the first 3 weeks; group 3 showed significantly better performance in the third week; and group 4 showed a significantly negative performance during the 4th and 6th weeks. CONCLUSION: Early application of HVPC had a positive effect in the treatment of the spinal cord region and the sciatic nerve root ganglion with a dispersive electrode on the contralateral lumbar region or on the gastrocnemius. However, HVPC had a negative effect in the treatment with an active electrode on the gastrocnemius and a dispersive electrode on the contralateral thigh. Level of evidence II, Prospective comparative study.

Avaliação do exercício físico como fator de analgesia em um modelo experimental de ciatalgia / Physical exercise assessment as an analgesia factor in a sciatica experimental model

OBJETIVO: Avaliar a eficácia do exercício físico (natação e salto) atuando na redução do quadro álgico de ratos submetidos a um modelo experimental de ciatalgia. MÉTODOS: 24 ratos Wistar foram divididos em quatro grupos: grupo Placebo (GP), grupo Natação (GN), grupo Natação 10 por cento (GN10) e grupo Salto (GS). Todos os grupos foram submetidos ao modelo de ciatalgia e avaliados em relação à dor pós-exercício pelo teste de incapacidade funcional e pelo filamento de Von Frey. RESULTADOS: Na comparação intragrupos houve diferenças significativas, para todos os grupos, nos momentos pós-lesão comparados com o pré-lesão, por ambos os instrumentos de avaliação. Com o filamento de Von Frey observou-se diferença significativa nos grupos GN10 e GS nos momentos finais de avaliação. Na comparação intergrupos não houve diferenças significativas com nenhum instrumento de avaliação. CONCLUSÃO: O tratamento com exercício físico não foi eficaz para reduzir o quadro álgico de ratos submetidos à ciatalgia.

OBJECTIVE: To evaluate the efficacy of physical exercise (swimming and jumping), with and without overload, working in reducing the pain of rats undergone to an experimental model of sciatica. METHODS: 24 rats were divided into four groups: Placebo (GP), Swimming Group (NG) Swimming 10 percent Group (GN10) and Leap Group (GS). All groups were submitted to the experimental sciatica model and assessed for pain post-exercise for the Functional Disability Test and the Von Frey filament. RESULTS: In comparison within groups there were significant differences in the moments after injury with the pre-injury, for both assessment instruments. With Von Frey filament was observed a significant difference in group GN10 and GS in the final moments of evaluation. In comparisons between groups were not statistically significant differences obtained with any assessment instrument. CONCLUSION: Treatment with physical exercise was not effective in reducing pain in rats subjected to experimental sciatica model.

Magnetic stimulation accelerating rehabilitation of peripheral nerve injury / 华中科技大学学报（医学）（英德文版）

The effect of magnetic stimulation (MS) on sciatic nerve injury was observed. After sciatic nerve was crushed in 40 Sprague Dawley (SD) rats, one randomly selected group (group D) was subjected, from the 4th day post-operatively to 3 min of continuous 70% of maximum output of MS daily for 8 weeks. The other group (group E) served as a control group. The nerve regeneration and motor function recovery were evaluated by walking track analysis (sciatic function index, SFI; toe spreading reflex, TSR), electrophysiological, histological and acetylcholineesterase histochemistry. The SFI in the group D was greater than in the group E with the difference being statistically significant (P 6.5 microns) in the group D was greater than in the control group with the difference being statistically significant (P 0.05). It can be concluded that MS can enhance functional recovery and has a considerable effect in the treatment of the peripheral nerve injury.