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Objective:To observe the effects of rolling method massager on local tissue morphology, tissue and serum TNF-α and IL-1β in rabbits with skeletal muscle injury at different time points; To investigate the mechanism of temporal effect of rolling method action on skeletal muscle injury.Methods:Totally 72 New Zealand rabbits were divided into blank group, model group and rolling method treatment group according to random number table method, with 24 rabbits in each group. Rabbits in each group were divided into 1 d, 3 d, 5 d, 7 d, 9 d and 11 d subgroups according to the time point of injury, with 4 rabbits in each group. Blunt contusion was used to model the model group and the rolling method treatment group. Each subgroup of the rolling method treatment group was subjected to rolling method intervention for 3 d, using a homemade rolling method massager, 2 times/d, 3 min/time. At 24 h after the completion of the intervention, the histomorphological changes were observed by HE staining, and the TNF-α and IL-1β contents in serum and damaged skeletal muscle tissues were detected by ELISA.Results:Compared with the blank group, the inflammatory cell infiltration in the model group was obvious, edema was severe, and myofibers were broken; the inflammatory cell infiltration in the 1 d rolling method treatment group was intensified, myocytes were apoptotic, and myofibers were broken and necrosed more seriously; the inflammation in the 7 d rolling method treatment group was obviously improved with the best effect, and the difference with normal healthy muscle tissue was smaller. After modeling, TNF-α and IL-1β levels in skeletal muscle tissues and serum TNF-α levels were higher in the 3 d model group than in the 1 d model group ( P<0.05). Compared with the blank group, TNF-α and IL-1β levels in skeletal muscle tissues and serum increased in each subgroup of the model group and each subgroup of the rolling method treatment group ( P<0.01); Compared with the 1 d model group, TNF-α and IL-1β levels in skeletal muscle tissues and serum TNF-α levels increased in the 1 d rolling method treatment group. The levels of TNF-α and IL-1β in the 3 d, 5 d, 7 d, 9 d and 11 d rolling method treatment group were lower than those in the model group subgroup ( P<0.05). TNF-α and IL-1β levels in skeletal muscle tissues and serum TNF-α levels were higher in the 1 d, 3 d and 5 d rolling method treatment group than in the 7 d rolling method treatment group ( P<0.05). TNF-α levels in skeletal muscle tissues were higher in the 1 d and 3 d rolling method treatment group than in the 7 d rolling method treatment group ( P<0.05). Conclusion:The inflammatory factors in the rolling treated group were significantly higher at 1 d after skeletal muscle injury, indicating that treatment with the rolling method was inappropriate at this time; seven days after injury, the application of rolling method can reduce the inflammatory effect, accelerate the repair of skeletal muscle, and improve the quality of functional recovery.
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@#Duchene muscular dystrophy (DMD) is a serious progressive muscular dystrophy.Reports in recent years about abnormal lipid in DMD patients have increased, yet little attention has been paid to liver lipid.This study aimed to explore the effect of dystrophin gene defect on liver lipid synthesis.7-week-old mdx male mice were used as DMD model.The conditions of liver function, liver lipid accumulation and liver lipid synthesis were determined through liver tissue morphological examination, blood biochemical examination, and detection of hepatic gene and protein expression.The results showed that lipid droplets in liver of mdx mice increased significantly.The contents of total cholesterol and triglyceride in liver, aspartate aminotransferase and alanine aminotransferase in serum increased.The gene and protein expression of hepatic lipid synthesis-related enzymes such as fatty acid synthase, acetyl CoA carboxylase, and sterol regulatory element binding protein 1-c were up-regulated.These results showed accumulation of liver lipid in 7-week-old mdx male mice.
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BACKGROUND: In recent years, resveratrol has been studied a lot on the inhibition of tissue fibrosis, but the effect of resveratrol on the rehabilitation of muscle injury has been rarely reported. OBJECTIVE: To observe the expression of basic fibroblast growth factor (bFGF) and insulin-like growth factor 1 (IGF-1) protein in the repair of acute blunt trauma of the skeletal muscle, and to explore the mechanism by which resveratrol promotes the structural and functional recovery of damaged skeletal muscle. METHODS: Thirty-three New Zealand rabbits were randomly divided into three groups: Normal group (n=3), natural recovery group (n=15) and resveratrol group (n=15). The skeletal muscle contusion model was established by blunt violence except for the normal group. The natural recovery group was not treated and the resveratrol group was intragastrically given resveratrol after injury. The animals were euthanized at 1, 3, 7,14, and 21 days after injury. Infiltration of inflammatory cells and formation of collagen fibers were observed using hematoxylin-eosin staining and Masson staining. The expression of bFGF and IGF-1 protein in the skeletal muscle was detected by immunohistochemistry and immunoblotting. RESULTS AND CONCLUSION: (1) Hematoxylin-eosin staining results: In the normal group, the muscle fibers were presented with polygons, regular shape, tight arrangement, muscle nucleus evenly distributed under the sarcolemma, no hyperplasia and pyknosis, and sarcolemma intact. In the injury groups, blood cells were exuded at 1 day, and inflammatory cells infiltrated at 3 days, which reached the maximum at 7 days. The morphology of muscle fibers returned to normal at 21 days after injury. The resveratrol group was better than the natural recovery group in terms of inflammatory cell infiltration and repair time. (2) Masson staining results: There were few collagen fibers in normal muscle cells. After injury, the number of collagen fibers increased with the formation of scar tissue, and reached a peak at 14 days. The content of collagen fibers in the resveratrol group was lower than that in the natural recovery group. (3) Immunohistochemistry and immunoblotting results: The expression of bFGF and IGF-1 protein first increased and then decreased after injury. In both groups, the expression of bFGF and IGF-1 protein reached the peak at 7 days and was still at a high level at 21 days. The resveratrol group had significantly higher bFGF and IGF-1 levels than the natural recovery group (P<0.05). Overall, resveratrol can effectively accelerate the histological healing process and improve the healing quality of rabbit skeletal muscle after blunt trauma. Resveratrol significantly promotes the repair of damaged skeletal muscle by up-regulating bFGF and IGF-1 expression, but not altering the overall change of protein expression during skeletal muscle injury repair.
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Objective:To study the effect of treadmill exercise and massage shortly after acute injury on expression of key growth factor in muscle satellite cells activation, insulin-like growth factor-1 (IGF-1), and mitogen-activated protein kinase (MAPK) / mitogen-activated protein kinase kinase (MEK) / extracellular regulated protein kinases (ERK)1/2 signaling pathways in muscle satellite cell in rats. Methods:A total of 40 SPF male adult Sprague-Dawley rats were randomly divided into groups A (n = 8), B (n = 8), C (n = 8), D (n = 8) and E (n = 8). Group A did not receive any treatment, while the other rats were contused the gastrocnemius muscle with self-made impactor. Group B received no intervention, groups C and D received massage and treadmill exercise shortly after injury, respectively, while group E received both treadmill exercise and massage shortly after injury. As the model was established, samples of gastrocnemius were obtained from all the rats 24 hours after injury, and observed under HE staining, detected the expression of MyoD1 and MyoG mRNA with reverse transcription polymerase chain reaction (RT-PCR), and expression of IGF-1, p-MAPK, p-MEK and p-ERKI/2 protein with Western blotting. Results:The expression of MyoD1 mRNA was more in groups C, D and E than in group B, which was the most in group C; less expression of MyoG mRNA, which was the most in group E (P < 0.05). The expression of p-MAPK, p-MEK and p-EPK1/2 was more in groups C, D and E than in group B, which was the most in group D (P < 0.05). The expression of IGF-1 increased in group C compared with that in group B (P < 0.05), and it decreased in group D (P < 0.05). Conclusion:Early intervention of treadmill exercise and massage may promote the activation of muscle satellite cells in different ways.
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Objective To explore the effect of Shenqi Fufang (参芪复方,SF) on skeletal muscle damage of type 2 diabetes mellitus (T2DM) and its possible mechanism.Methods Eighteen rats with spontaneous type 2 diabetes mellitus (GK) were randomized into the model group,SF group and sitagliptin group with six rats in each group,and six more Wistar rats were selected as the control group.Each group was given high fat diet for 8 weeks to build T2DM model except for the control group.At the same time,the control group and the model group were given normal saline 5 ml/(kg-d) by gastric perfusion,the SF group was given SF extract 1.44g/(kg · d) by gastric perfusion,and sitagliptin group was given sitagliptin phosphate suspension 16ml/(kg · d) by gastric perfusion.Eight weeks later,the levels of serum insulin-like growth factor 1 (IGF-1),tumor necrosis factor-αr (TNF-a) and interleukin-1β (IL-1β)were measured in each group,the gastrocnemius muscle was taken out to get the wet weight and observe the pathological changes,and the expression of p70s6k1 protein was detected.Results Compared with the control group,the wet weight of the gastrocnemius muscle,the serum IGF-1 level and p70s6k1 protein expression in the model group significantly decreased (P ＜ 0.05),while the levels of serum TNF-α and IL-1β significantly increased (P ＜ 0.05).Through pathological observation,there existed gastrocnemius muscle cells atrophy,a larger area of edema and interstitial lymphocyte infiltration.Compared with the model group,the wet weight of the gastrocnemius muscle,IGF-1 content and p70s6k protein expression in the sitagliptin group and the SF group significantly increased,the contents of TNF-α and IL-l β significantly decreased (P ＜0.05),and there were no obvious muscle cell atrophy and edema,and also little inflammatory cell infiltration.There was no significant difference between the sitagliptin group and SF group (P ＞ 0.05).Conclusion SF could reduce the diabetic skeletal muscle injury;the potential mechanism seems to reduce the inflammatory factor content,improve IGF-1 resistance and maintain the skeletal muscle mass.
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The aim of this study was to analyze changes in the skeletal muscle tissue of rats after muscle stretch injury using fractal analysis. Nineteen rats were divided into three groups, Control (n= 5) (C), Lesion two days (n= 7) (L2), and Lesion seven days (n= 7) (L7). Histological slides of the gastrocnemius muscle of the animals were prepared and stained with Hematoxylin and eosin for analysis of the inflammatory process, and picrosirius for the demonstration of collagen. The stained slides were subsequently analyzed using Fractal Dimension (FD). The results showed high FD values of the inflammatory process in the experimental groups L2 and L7 in relation to C (p= 0.000). The analysis of collagen in the picrosirius stained slides showed high FD in the L2 group compared to the L7 (p= 0.0001), with no statistically significant difference among other groups. In summary, the present study demonstrated that fractal analysis was able to identify changes in the inflammatory process in injured skeletal muscle tissue.
El objetivo de la investigación fue observar las modificaciones en tejido muscular esquelético en ratas después de la lesión por estiramiento muscular con análisis fractal. En el estudio se incluyeron 19 ratas, divididas en tres grupos, Control (n= 5) (C), lesión dos días (n= 7) (L2) y lesión siete días (L7). Los cortes histológicos del músculo gastrocnemio fueron coloreados con hematoxilina-eosina para el análisis de la inflamación y picrosirius para la determinación del colágeno. Los cortes histológicos fueron posteriormente analizados por medio de dimensión fractal (FD). Los resultados mostraron valores elevados de FD en proceso inflamatorio en los grupos experimentales L2 y L7, en comparación con grupo C (p= 0,000). El análisis de colágeno mostró mayor FD en grupo L2 comparado con L7 (p= 0,0001), se observó diferencia estadísticamente significativa con los demás. En resumen, esta investigación ha demostrado que el análisis fractal fue capaz de identificar las alteraciones del proceso inflamatorio en tejido muscular esquelético después de la lesión.
Subject(s)
Animals , Male , Rats , Muscle, Skeletal/injuries , Muscle, Skeletal/pathology , Collagen/analysis , Fractals , Inflammation , Rats, WistarABSTRACT
O triatlo é um esporte de destaque e ampla participação mundial. Incorpora três diferentes modalidades de endurance - natação, ciclismo e corrida - dentro de um único evento. Há uma variedade de distâncias sobre as quais os eventos de triatlo são realizados, sendo a prova de ultradistância (ironman) a mais extensa. Autores diversos já relataram a ocorrência de lesões após esforço intenso, seja diretamente, através de alterações histológicas no sarcômero, ou indiretamente, pela quantificação da concentração de proteínas musculares específicas (biomarcadoras de lesão) no plasma. Entre esses marcadores de lesão muscular destacam-se a mioglobina e a creatina cinase. Efetivamente, a creatina cinase é o indicador bioquímico mais utilizado na literatura como indicador da ocorrência de lesão muscular. Dentro desse contexto justifica-se o objetivo do presente trabalho que visa verificar o efeito do exercício nas concentrações séricas de creatina cinase em triatletas de ultradistância frente a um período de competição. Para tanto, foram avaliados os dados das concentrações séricas de CK de 10 atletas que participaram da prova do Ironman Brasil de 2007. As análises sanguíneas foram realizadas em cinco períodos distintos: 19 dias antes da prova do ironman (CK1), 48 horas antes da prova (CK2), imediatamente após (CK3), cinco dias após (CK4) e 12 dias depois da prova (CK5). Os resultados apontaram aumento significativo nas concentrações de CK nos períodos 3 e 4 em relação aos demais períodos avaliados. Estas alterações evidenciam a influência do exercício exaustivo sobre as concentrações de CK, revelando a possibilidade de desenvolvimento de lesões musculares durante essa competição. Este fato reforça a importância do monitoramento de biomarcadores, como a CK, que permite a treinadores e atletas ajustarem suas cargas de treinamento para aumentar os benefícios do treinamento e para evitar o supertreinamento, melhorando o desempenho, a saúde e a qualidade de vida do atleta.
Triathlon is a popular sport with world wide participation. It combines three different endurance modalities - swimming, cycling and running - within a single event. There is a variety of distances on which triathlon events are made, the Ironman race being the longest. Many authors have already reported injury occurrence after intense exertion, either directly, through histological sarcomere alterations, or indirectly, over the quantification of specific muscle proteins concentration (injury biomarkers) in the plasma. Among these markers of muscle injury, Myoglobin and Creatine Kinase stand out. In fact, creatine kinase is the most used biochemical indicator of muscle injury occurrence. Within this context, it is justified the purpose of this study, that intends to verify exercise effects on serum levels of creatine kinase in ultra-distance triathletes in the course of a competition period. Serum levels of CK from 10 triathletes who competed in the Ironman Brazil event, 2007 were evaluated. Blood analyses were done at five distinct periods: 19 days before Ironman Brazil competition (CK1), 48 hours before it (CK2), immediately after it (CK3), five days after the competition (CK4) and 12 days after the event (CK5). The results showed significant increase on CK concentrations at periods 3 and 4, when compared to the other evaluated periods. These alterations evidence the influence of the Ironman competition exhaustive exercise over the CK concentrations, revealing the possibility of muscle injuries development during the event. This fact enhances the importance of biomarkers' monitoring, like CK, that allow coaches and athletes to adapt training loads to increase their benefits and to avoid overtraining, improving performance, health and quality of life.
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Humans , Male , Young Adult , Athletes , Creatine Kinase/analysis , Exercise , Muscle Fatigue , Biomarkers , Muscles/injuries , Bicycling , Running , SwimmingABSTRACT
O objetivo deste estudo foi avaliar os efeitos do ultrassom pulsado (USp) no reparo muscular em um modelo experimental de lesão lacerativa do músculo gastrocnêmio medial em ratos Wistar. Vinte ratos foram tratados diariamente com USp (50%), 1MHz, 0,57W/cm² de intensidade por 5 min. formando os grupos tratados (GT), e 20 animais constituíram os grupos controle (CG). A análise histológica, morfométrica (usando o método estereológico) e biomecânica (teste de tensão) foi realizada aos 4, 7, 14 e 24 dias após a lesão. As lesões apresentaram um padrão de reparo similar tanto nos GT como nos GC. Os volumes absolutos da lesão (VL) e das zonas central e de regeneração (VZC e VZR) diminuíram progressivamente ao longo do processo de reparo tanto nos GT como nos GC. No GT, o VL diminuiu significativamente em todos os dias experimentais, sendo que VZC uma diminuição significante aos 4 e 7 dias pós-lesão e o VZR aos 14 dias pós-lesão. A fração de volume de vasos sanguíneos e a fração de superfície de vasos sanguíneos foi maior nos GT aos 4 e 7 dias pós-lesão em relação aos respectivos controles. Apesar de haver uma tendência a um maior volume absoluto de vasos sanguíneos nos GT, a análise estatística mostrou que existe uma maior volume de vasos somente aos 4 dias pós-lesão. Não houve diferença significante na área de superfície total de vasos sanguíneos na lesão quando se comparam os grupos entre si. Houve um aumento significante na fração de volume de fibras de colágeno na lesão nos GT aos 4,7 e 14 dias pós-lesão. Houve um aumento significante na tensão máxima e na rigidez nos GT aos 4 e 24 dias após a lesão. Não houve diferença significante na deformação relativa entre GC e GT. Os resultados sugerem que o USp otimiza a fase inflamatória e estimula as fases proliferativa e de remodelamento, promovendo uma diminuição mais acentuada no volume da lesão, estimulando a angiogênese, assim como, a deposição e a organização do colágeno fibrilar. Os achados histológicos...
The aim of this study was to evaluate the effect of the pulsed ultrasound therapy (PUT) in stimulating muscle repair in an experimental model of lacerative gastrocnemius medialis muscle lesion in 40 Wistar rats. Twenty rats were treated (TG) daily with 1MHz pulsed ultrasound (50%) at 0.57W/cm² for 5 min, and 20 were control animals (CG). Muscle samples were harvested up on postoperative days 4, 7, 14 and 24 for stereological, histological, and biomechanical analyses. The lesions presented similar repair pattern in both TG and CG. The lesion volume (VL) and the central and regenerative zones volumes (VCZ and VRZ) had a progressive deacrease through the post lesion period both in the TG and CG. The VL decrease was significantly greater in the TG in all experimental days, the VCZ decrease was significant in the TG at 4 and 7 days post lesion, and the VRZ decrease was significant at 14 days post lesion in the TG. Statistically significant increase was found in the blood vessels volume fraction and in the surface fraction of blood vessels in the TG at 4 and 7 days post lesion compared to respective CG. Although there was a tendency to have a greater blood vessels absolute volume within lesion in the TG, the statistical analysis showed that it was only larger at 4 days after surgery in US treated group. No statistically significant increase was found in the surface total area within lesion in all experimental days between CG and TG. There was a significant increase in the volume fraction of fibrilar collagen within the lesion in the TG at 4, 7 and 14 days post lesion. The biomechanical data showed a significant increase in the maximal stress and stiffness in the TG at 4 and 24 days after lesion, although there was a progressive increase of these variables both in the CG and TG. There was no significant difference in the maximal elongation, between CG and TG. Our data suggest that the PUT acts as an inflammatory optimizer and stimulates the proliferative and...
Subject(s)
Angiogenesis Inducing Agents , Biomechanical Phenomena , Collagen , Histology , Muscle, Skeletal/injuries , Ultrasonic TherapyABSTRACT
Objective To observe the effect of the injection of myoblast carrying human insulin-like growth factor-1(hIGF-1) on the expression of endogenous IGF-1 mRNA and IGF-1 level in mice skeletal muscle following injury.Methods Seventy two male C3H mice(20~30g,7~11w)were randomly divided into three groups(24 mice in each group) with four mice normal controls.Applied a falling hit from certain height at the medial calf of right lower limbs in three groups,the injured skeletal muscle model was successfully simulated.Three days following injury,the mice in group A and B were injected with 1?106 myoblasts either carried with or without hIGF-1 gene respectively and the mice in group C were injected with 100?l saline at the injured muscle.Three mice in each group were sacrificed randomly at day 2,5,10,15,20,30 after contusion.The expression level of mIGF-1 was assessed by immunohistochemical staining and real time PCR.Results mIGF-1 mRNA expression and mIGF-1 factor secretion were observed in all three groups;the amount of mIGF-1 mRNA expression and mIGF-1 secretion in group A were significant higher than that in group B and C.Conclusion Myoblast carrying hIGF-1 transplantation could promote endogenous IGF-1 secretion in injured skeletal muscle.
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Objective To observe the survival of myoblasts carrying hIGF-1 gene transplanted into the mice, and the expression of hIGF-1 in the transplanted mice. Methods Eighty four male C3H mice(20～30g,7～11w)were divided into four groups: group A, B, C and D (20 mice each group), and the remaining four mice were used as normal control. At the middle of the right gastrocnemius muscle, the mice in group A and B were injected with 1?10~6 myoblasts either carried with or without hIGF-1 gene. Muscle contusion at the middle of the right gastrocnemius muscle of the mice in group C and D was produced. At day 3 following injury, they were injected with 1?10~6 myoblasts either carried with hIGF-1 gene (group C) or without hIGF-1 gene (group D). At the day 2, 5, 10, 20, 30 after injection, four mice of each group were sacrificed randomly. BrdU staining in all mice were performed to evaluate cells surviving, and the expression level of hIGF-1 in group A and C was assessed by immunohistochemical staining and real-time-PCR. Results The BrdU staining in both normal and injured mice transplanted with myoblast carried with or without hIGF-1 were positive. hIGF-1 was expressed and secreted in both group A and C. Conclusion The myoblast carrying hIGF-1 gene transplanted into normal or injured mice can survive for a certain period of time, and can secrete hIGF-1.