【摘要】 目的 探索“三法三穴”推拿通过调控Notch1信号通路与肌细胞生成素(MyoG)、肌源性调节因子4(Mrf4)蛋白表达改善失神经肌萎缩的机制。方法 将40只雄性SD大鼠随机分为正常组、假手术组、模型组、推拿组、推拿+激动剂组5组。模型组、推拿组、推拿+激动剂组大鼠建立SNI模型;假手术组仅暴露坐骨神经。使用智能推拿手法模拟仪施点法、拨法、揉法作用于推拿组及推拿+激动剂组大鼠患侧后肢殷门、承山、阳陵泉3穴。采用斜板实验依次评估鼠后肢肌力变化;Masson染色观察患侧腓肠肌形态并测定胶原纤维/肌纤维面积比;RT-PCR检测腓肠肌组织Notch1通路因子(Notch1、Jagged1、Hes1)m-RNA表达;Western Blot检测腓肠肌组织Notchl通路因子及MyoG、Mrf4蛋白表达。结果 与正常组、假手术组比较,模型组大鼠后肢肌力显著减弱(P<0.01),肌纤维束排列结构紊乱,胶原纤维明显增多,胶原纤维/肌纤维面积比显著上升(P<0.01),Notch1、Jagged1、Hes1 m-RNA和蛋白表达显著增高(P<0.05),MyoG、Mrf4蛋白表达显著降低(P<0.01);与模型组比较,推拿组后肢肌力显著增强(P<0.01),胶原纤维增生减少、胶原纤维/肌纤维面积比显著下降(P<0.01)。Notch1、Jagged1、Hes1 m-RNA和蛋白表达显著降低(P<0.01),MyoG、Mrf4蛋白表达显著升高(P<0.01);与推拿组相比,推拿+激动剂组Notch1、Jagged1、Hes1 m-RNA和蛋白表达显著增强(P<0.05),MyoG、Mrf4蛋白表达显著降低(P<0.01)。结论 “三法三穴”推拿可通过抑制Notch1信号通路表达而上调MyoG、Mrf4的表达,促进肌卫星细胞分化,延缓失神经萎缩进程。更多还原

【Abstract】 Objective To investigate the mechanisms by which the "three methods and three acupoints" Tuina alleviates denervated muscle atrophy through modulation of the Notch1 signaling pathway and the expression levels of myogenin(MyoG)and myogenic regulatory factor 4(Mrf4).Methods Forty male Sprague-Daw ley rats were randomly assigned to 5 groups:normal group,sham-operated group,model group,Tuina group,and Tuina+agonist group.Sciatic nerve injury(SNI) models were established in the model,Tuina,and Tuina+agonist groups,while the sham-operated group underwent sciatic nerve exposure only.An intelligent Tuina simulation instrument was used to stimulate the acupoints Yinmen,Chengshan,and Yanglingquan.Hind limb muscle strength was evaluated via the inclined plate test,and morphological changes in the gastroc nemius muscle were assessed using Masson staining to determine the collagen-to-muscle fiber area ratio.The mRNA levels of Notch1 signaling components(Notchl,Jagged1,and Hesl) in gastrocnemius muscle tissue were quantified by RT-PCR,while protein expression levels of Notchl,MyoG,and Mrf4 were determined via Western Blot.Results Compared with normal and shamoperated groups,rats in model group exhibited significantly diminished hind limb muscle strength(P<0.01),disorganized muscle fiber arc hitecture,increased collagen deposition,and an elevated collagen-to-muscle fiber area ratio(P<0.01).Moreover,both mRNA and protein expression levels of Notchl,Jagged 1,and Hesl were significantly increased(P<0.05),whereas MyoG and Mrf4 protein expressions were markedly decreased(P<0.01).Inc ontrast,Tuina group demonstrated significant improveme nts in hind limb muscle strength(P<0.01),re duced collagen proliferation,and a lower collage n-to-muscle fiber area ratio(P<0.01).Additionally,mRNA and protein levels of Notchl,Jaggedl,and Hes1 were significantly downregulated(P<0.01),whereas MyoG and Mrf4 protein expressions were substantially upre gulated(P<0.0 1).Compared with Tuina group,Tuina+agonist group exhibited significantly elevated mRNA and protein expression levels of Notchl,Jaggedl,and Hes1(P<0.05) along with significantly reduced MyoG and Mrf4 protein expressions(P<0.01).Conclusion The "three methods and three acupoints" Tuina inhibits activation of the Notchl signaling pathway,thereby upregulating the expression of MyoG and Mrf4,promoting the differentiation of muscle satellite cells,and delaying the progression of denervation-induced muscle atrophy.更多还原