Denervation often results in skeletal muscle atrophy.Different mechanisms seem to be involved in the determination between denervated slow and fast skeletal muscle atrophy.At the epigenetic level,mi RNAs are thought t...Denervation often results in skeletal muscle atrophy.Different mechanisms seem to be involved in the determination between denervated slow and fast skeletal muscle atrophy.At the epigenetic level,mi RNAs are thought to be highly involved in the pathophysiological progress of denervated muscles.We used mi RNA microarrays to determine mi RNA expression profiles from a typical slow muscle（soleus muscle） and a typical fast muscle（tibialis anterior muscle） at an early denervation stage in a rat model.Results showed that mi R-206,mi R-195,mi R-23 a,and mi R-30 e might be key factors in the transformation process from slow to fast muscle in denervated slow muscles.Additionally,certain mi RNA molecules（mi R-214,mi R-221,mi R-222,mi R-152,mi R-320,and Let-7e） could be key regulatory factors in the denervated atrophy process involved in fast muscle.Analysis of signaling pathway networks revealed the mi RNA molecules that were responsible for regulating certain signaling pathways,which were the final targets（e.g.,p38 MAPK pathway; Pax3/Pax7 regulates Utrophin and follistatin by HDAC4; IGF1/PI3K/Akt/m TOR pathway regulates atrogin-1 and Mu RF1 expression via Fox O phosphorylation）.Our results provide a better understanding of the mechanisms of denervated skeletal muscle pathophysiology.展开更多
[目的]探讨低强度脉冲超声波(LIPUS)对失神经骨骼肌萎缩的影响。[方法]50只健康雄性SD大鼠随机分为五组:假手术组、模型组、60 m W/cm2、110 m W/cm2、170 m W/cm2LIPUS治疗组(即A、B、C、D、E组),n=10。右股后外侧纵向切口暴露并切断...[目的]探讨低强度脉冲超声波(LIPUS)对失神经骨骼肌萎缩的影响。[方法]50只健康雄性SD大鼠随机分为五组:假手术组、模型组、60 m W/cm2、110 m W/cm2、170 m W/cm2LIPUS治疗组(即A、B、C、D、E组),n=10。右股后外侧纵向切口暴露并切断坐骨神经造成失神经动物模型,A组不切断神经。术后1 d,C、D、E组术侧腓肠肌分别给予相应强度LIPUS治疗(A、B组不行任何治疗)。术后4周和8周,测定术侧腓肠肌湿重比和肌纤维直径、截面积,Western Blot检测Caspase-3、Caspase-8、Caspase-9表达,TUNEL法检测细胞凋亡,透射电镜观察腓肠肌超微结构。[结果]术侧腓肠肌湿重比和肌纤维直径、截面积,B组明显低于C、D、E组,差异有统计学意义(P<0.05)。Caspase-3、Caspase-8、Caspase-9蛋白表达及细胞凋亡指数,C、D、E组明显低于B组(P<0.05)。透射电镜显示,C、D、E组肌丝溶解、Z线断裂和线粒体肿胀、空泡化均轻于B组。[结论]LIPUS可延缓失神经骨骼肌萎缩进程,其机制可能与调控凋亡相关蛋白表达、减少细胞凋亡有关。展开更多
The present study observed sciatic nerve and gastrocnemius muscle changes in denervated rats using morphology methods, and assessed expression of perlecan, an extracellular matrix component, which is located at the sk...The present study observed sciatic nerve and gastrocnemius muscle changes in denervated rats using morphology methods, and assessed expression of perlecan, an extracellular matrix component, which is located at the skeletal muscle cell surface as acetylcholine esterase, as well as synaptophysin, a synaptic marker. Results showed degeneration and inflammation following transection of the sciatic nerve. In addition, the sciatic nerve-dominated skeletal muscle degenerated with mild inflammation, indicating that skeletal muscle atrophy primarily contributed to denervation-induced nutritional disturbances. With prolonged injury time （1-4 weeks post-injury）, perlecan expression gradually decreased and reached the lowest level at 4 weeks, but synaptophysin expression remained unchanged after denervation. Results suggested that perlecan expression was more sensitive to denervation and reflected regional extracellular matrix changes following denervation.展开更多
基金supported by the National Natural Science Foundation of China,No.81101365,81171722 and 81000805
文摘Denervation often results in skeletal muscle atrophy.Different mechanisms seem to be involved in the determination between denervated slow and fast skeletal muscle atrophy.At the epigenetic level,mi RNAs are thought to be highly involved in the pathophysiological progress of denervated muscles.We used mi RNA microarrays to determine mi RNA expression profiles from a typical slow muscle（soleus muscle） and a typical fast muscle（tibialis anterior muscle） at an early denervation stage in a rat model.Results showed that mi R-206,mi R-195,mi R-23 a,and mi R-30 e might be key factors in the transformation process from slow to fast muscle in denervated slow muscles.Additionally,certain mi RNA molecules（mi R-214,mi R-221,mi R-222,mi R-152,mi R-320,and Let-7e） could be key regulatory factors in the denervated atrophy process involved in fast muscle.Analysis of signaling pathway networks revealed the mi RNA molecules that were responsible for regulating certain signaling pathways,which were the final targets（e.g.,p38 MAPK pathway; Pax3/Pax7 regulates Utrophin and follistatin by HDAC4; IGF1/PI3K/Akt/m TOR pathway regulates atrogin-1 and Mu RF1 expression via Fox O phosphorylation）.Our results provide a better understanding of the mechanisms of denervated skeletal muscle pathophysiology.
文摘[目的]探讨低强度脉冲超声波(LIPUS)对失神经骨骼肌萎缩的影响。[方法]50只健康雄性SD大鼠随机分为五组:假手术组、模型组、60 m W/cm2、110 m W/cm2、170 m W/cm2LIPUS治疗组(即A、B、C、D、E组),n=10。右股后外侧纵向切口暴露并切断坐骨神经造成失神经动物模型,A组不切断神经。术后1 d,C、D、E组术侧腓肠肌分别给予相应强度LIPUS治疗(A、B组不行任何治疗)。术后4周和8周,测定术侧腓肠肌湿重比和肌纤维直径、截面积,Western Blot检测Caspase-3、Caspase-8、Caspase-9表达,TUNEL法检测细胞凋亡,透射电镜观察腓肠肌超微结构。[结果]术侧腓肠肌湿重比和肌纤维直径、截面积,B组明显低于C、D、E组,差异有统计学意义(P<0.05)。Caspase-3、Caspase-8、Caspase-9蛋白表达及细胞凋亡指数,C、D、E组明显低于B组(P<0.05)。透射电镜显示,C、D、E组肌丝溶解、Z线断裂和线粒体肿胀、空泡化均轻于B组。[结论]LIPUS可延缓失神经骨骼肌萎缩进程,其机制可能与调控凋亡相关蛋白表达、减少细胞凋亡有关。
基金supported by the National Natural Science Foundation of China,No.30900300/C1002
文摘The present study observed sciatic nerve and gastrocnemius muscle changes in denervated rats using morphology methods, and assessed expression of perlecan, an extracellular matrix component, which is located at the skeletal muscle cell surface as acetylcholine esterase, as well as synaptophysin, a synaptic marker. Results showed degeneration and inflammation following transection of the sciatic nerve. In addition, the sciatic nerve-dominated skeletal muscle degenerated with mild inflammation, indicating that skeletal muscle atrophy primarily contributed to denervation-induced nutritional disturbances. With prolonged injury time （1-4 weeks post-injury）, perlecan expression gradually decreased and reached the lowest level at 4 weeks, but synaptophysin expression remained unchanged after denervation. Results suggested that perlecan expression was more sensitive to denervation and reflected regional extracellular matrix changes following denervation.
