Adipose-derived stem cells have been shown to promote peripheral nerve regeneration through the paracrine secretion of neurotrophic factors. However, it is unclear whether these cells can promote myogenic differentiat...Adipose-derived stem cells have been shown to promote peripheral nerve regeneration through the paracrine secretion of neurotrophic factors. However, it is unclear whether these cells can promote myogenic differentiation in muscular dystrophy. Adipose-derived stem cells （6 × 106） were injected into the gastrocnemius muscle of mdx mice at various sites. Dystrophin expression was found in the muscle fibers. Phosphorylation levels of Akt, mammalian target of rapamycin （mTOR）, eIF-4E binding protein 1 and $6 kinase 1 were increased, and the Akt/mTOR pathway was activated. Simultaneously, myogenin levels were increased, whereas cleaved caspase 3 and vimentin levels were decreased. Necrosis and fibrosis were reduced in the muscle fibers. These findings suggest that adipose-derived stem cells promote the re- generation and survival of muscle cells by inhibiting apoptosis and fibrosis, thereby alleviating muscle damage in muscular dystrophy.展开更多
Background:Long non-coding RNAs(lncRNAs)are emerging key regulators involved in a variety of biological processes such as cell differentiation and development.The balance between myogenesis and adipogenesis is crucial...Background:Long non-coding RNAs(lncRNAs)are emerging key regulators involved in a variety of biological processes such as cell differentiation and development.The balance between myogenesis and adipogenesis is crucial for skeletal muscle homeostasis in humans and meat quality in farm animals.The present study aimed to reveal the global transcriptomic profiles of adipogenic(Adi-)and myogenic(Myo-)precursors derived from porcine skeletal muscle and identify lncRNAs involved in the modulation of myogenesis homeostasis in porcine skeletal muscle.Results:In this study,a total of 655 novel individual lncRNAs including differentially expressed 24 lncRNAs,and 755 differentially expressed mRNAs were identified(fold change≥2 or≤0.5 and adjusted P<0.05).Integrated results of Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis accompanied by the variation of intracellular Ca2+concentration highlighted Lnc-ADAMTS9 involved in the modulation of myogenesis homeostasis in porcine skeletal muscle.Although Lnc-ADAMTS9 knock-down did not alter the mRNA expression of ADAMTS9,we demonstrated that Lnc-ADAMTS9 can promote myogenic proliferation and myogenic differentiation of myogenic precursors through inhibiting the ERK/MAPK signaling pathway.Conclusion:We deciphered a comprehensive catalog of mRNAs and lncRNAs that might be involved in the regulation of myogenesis and adipogenesis homeostasis in the skeletal muscle of pigs.The Lnc-ADAMTS9 exerts an essential role in myogenesis through the ERK signaling pathway.展开更多
【目的】目前,越来越多的研究证明环状RNA(circRNA)在牛肌肉发育过程中扮演着重要的角色,但其分子调控机理尚未完善。通过挖掘与牛肌肉发育相关的circRNA的作用机制,为进一步阐明其调控牛肌肉发育的分子机制奠定基础。【方法】以前期分...【目的】目前,越来越多的研究证明环状RNA(circRNA)在牛肌肉发育过程中扮演着重要的角色,但其分子调控机理尚未完善。通过挖掘与牛肌肉发育相关的circRNA的作用机制,为进一步阐明其调控牛肌肉发育的分子机制奠定基础。【方法】以前期分析的增殖期(GM)与成肌分化期(DM)黄牛肌肉干细胞(MuSCs)的RNA-seq测序结果为基础,筛选出显著差异表达的circRNA,circCEP85L。采集新鲜黄牛胎牛的心脏、肝脏、脾脏、肺脏、肾脏、肌肉、肠和胃的组织样本,分离培养黄牛肌肉干细胞并诱导成肌分化,收集黄牛体外培养的GM与DM细胞,分别提取RNA并反转录为cDNA。通过实时荧光定量PCR(quantitative real time PCR,qRT-PCR)检测circCEP85L在不同组织及不同细胞状态的表达规律。同时,设计特异性引物扩增circCEP85L全长,构建过表达载体p-circCEP85L,质粒转染MuSCs后收集过表达circCEP85L细胞样本。以过表达质粒pCD5-ciR细胞样本为对照,采用qRT-PCR、流式细胞术、Western Blot及免疫荧光等技术检测过表达circCEP85L对黄牛MuSCs增殖、凋亡及成肌分化的影响。【结果】PCR电泳结果证明circCEP85L环化位点真实存在。CircCEP85L在多种组织中表达,并在DM期的表达量显著高于GM期(P<0.001);为了进一步探究对circCEP85L黄牛MuSCs的影响。将过表达载体p-circCEP85L与对照载体pCD5-ciR转染体外培养的黄牛MuSCs,继续培养24 h之后,EdU结果表明过表达circCEP85L能显著降低EdU阳性细胞比例(P<0.001);流式周期检测结果表明,过表达circCEP85L增加了G0/G1期细胞比例,显著减少S期细胞比例(P<0.001);流式凋亡结果表明,过表达circCEP85L显著抑制MuSCs的凋亡率(P<0.05)。QRT-PCR及Western blot检测黄牛MuSCs增殖及凋亡相关基因的表达情况,结果表明过表达circCEP85L后显著降低了黄牛MuSCs增殖及凋亡相关基因的mRNA表达水平(P<0.001),凋亡蛋白BAX的表达量也显著降低(P<0.01)。此外,为了展开更多
文摘【目的】肌纤维类型及其转化的调节是改善肉质的重要途径,最新研究表明,m6A RNA甲基化修饰在肌肉的分化中发挥着重要作用。以优良的地方品种--广西麻鸡作为研究对象,研究其性成熟日龄不同部位肌纤维类型的组成差异,探究m6A甲基化转移酶相关基因甲基化转移酶样蛋白3/14(methyltransferase like 3/14,METTL3/14)、Wilm肿瘤1-相关蛋白(Wilms’tumor 1-associating protein,WTAP)和病毒样m6A甲基转化酶(vir like m6A methyltransferase associated,VIRMA,也称KIAA1429)在不同部位肌肉组织和成肌细胞分化前后的表达差异,为阐明肌纤维类型组成及转换的调控机理提供参考。【方法】采用ATPase染色法比较广西麻鸡胸部、腿部和背部肌肉群7个部位肌纤维类型、直径和密度等肌纤维性状差异,采用比色法检测成肌细胞分化前后不同时间点内源性m6A甲基化水平,采用实时荧光定量PCR方法检测上述4个基因在广西麻鸡7个部位肌肉以及成肌细胞分化前后的表达差异,并将其与肌纤维性状和m6A甲基化水平进行相关性分析。【结果】广西麻鸡性成熟日龄胸部肌肉群的胸大肌和胸小肌全部由白肌纤维组成,腿部肌肉群的耻坐骨肌内侧头、腓肠肌内侧头和缝匠肌均以红肌纤维为主,而髂胫外侧肌以白肌纤维为主,背部肌肉群的背阔肌则以红肌纤维为主;总体上,红肌纤维比例多的肌肉肌纤维密度显著高于白肌纤维比例多的肌肉。METTL3、METTL14、WTAP和KIAA1429基因表达存在显著的组织和时间特异性,总体上,在红肌纤维为主的肌肉中的表达量高于白肌纤维为主的肌肉,在分化期成肌细胞中的表达量要显著高于增殖期成肌细胞。肌肉中METTL3、METTL14和WTAP具有相似的表达模式,均在背阔肌中表达量最高,显著高于其他肌肉组织;在耻坐骨肌内侧头和腓肠肌内侧头的表达量次之,显著高于缝匠肌、胸大肌、胸小肌和髂胫外侧肌。K
基金supported by the National Natural Science Foundation of China,No.30370510,30870851,81271401the Joint Fund of National Natural Science Foundation of ChinaNatural Science Foundation of Guangdong Province of China,No.U1032004
文摘Adipose-derived stem cells have been shown to promote peripheral nerve regeneration through the paracrine secretion of neurotrophic factors. However, it is unclear whether these cells can promote myogenic differentiation in muscular dystrophy. Adipose-derived stem cells （6 × 106） were injected into the gastrocnemius muscle of mdx mice at various sites. Dystrophin expression was found in the muscle fibers. Phosphorylation levels of Akt, mammalian target of rapamycin （mTOR）, eIF-4E binding protein 1 and $6 kinase 1 were increased, and the Akt/mTOR pathway was activated. Simultaneously, myogenin levels were increased, whereas cleaved caspase 3 and vimentin levels were decreased. Necrosis and fibrosis were reduced in the muscle fibers. These findings suggest that adipose-derived stem cells promote the re- generation and survival of muscle cells by inhibiting apoptosis and fibrosis, thereby alleviating muscle damage in muscular dystrophy.
基金supported by the National key research and development program of China(Grant No.2018YFD0500402)the National Natural Science Foundation of China(Grant No.31790412,Grant No.31672431)the National Key Basic Research Program of China(2013CB127302。
文摘Background:Long non-coding RNAs(lncRNAs)are emerging key regulators involved in a variety of biological processes such as cell differentiation and development.The balance between myogenesis and adipogenesis is crucial for skeletal muscle homeostasis in humans and meat quality in farm animals.The present study aimed to reveal the global transcriptomic profiles of adipogenic(Adi-)and myogenic(Myo-)precursors derived from porcine skeletal muscle and identify lncRNAs involved in the modulation of myogenesis homeostasis in porcine skeletal muscle.Results:In this study,a total of 655 novel individual lncRNAs including differentially expressed 24 lncRNAs,and 755 differentially expressed mRNAs were identified(fold change≥2 or≤0.5 and adjusted P<0.05).Integrated results of Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis accompanied by the variation of intracellular Ca2+concentration highlighted Lnc-ADAMTS9 involved in the modulation of myogenesis homeostasis in porcine skeletal muscle.Although Lnc-ADAMTS9 knock-down did not alter the mRNA expression of ADAMTS9,we demonstrated that Lnc-ADAMTS9 can promote myogenic proliferation and myogenic differentiation of myogenic precursors through inhibiting the ERK/MAPK signaling pathway.Conclusion:We deciphered a comprehensive catalog of mRNAs and lncRNAs that might be involved in the regulation of myogenesis and adipogenesis homeostasis in the skeletal muscle of pigs.The Lnc-ADAMTS9 exerts an essential role in myogenesis through the ERK signaling pathway.
文摘【目的】目前,越来越多的研究证明环状RNA(circRNA)在牛肌肉发育过程中扮演着重要的角色,但其分子调控机理尚未完善。通过挖掘与牛肌肉发育相关的circRNA的作用机制,为进一步阐明其调控牛肌肉发育的分子机制奠定基础。【方法】以前期分析的增殖期(GM)与成肌分化期(DM)黄牛肌肉干细胞(MuSCs)的RNA-seq测序结果为基础,筛选出显著差异表达的circRNA,circCEP85L。采集新鲜黄牛胎牛的心脏、肝脏、脾脏、肺脏、肾脏、肌肉、肠和胃的组织样本,分离培养黄牛肌肉干细胞并诱导成肌分化,收集黄牛体外培养的GM与DM细胞,分别提取RNA并反转录为cDNA。通过实时荧光定量PCR(quantitative real time PCR,qRT-PCR)检测circCEP85L在不同组织及不同细胞状态的表达规律。同时,设计特异性引物扩增circCEP85L全长,构建过表达载体p-circCEP85L,质粒转染MuSCs后收集过表达circCEP85L细胞样本。以过表达质粒pCD5-ciR细胞样本为对照,采用qRT-PCR、流式细胞术、Western Blot及免疫荧光等技术检测过表达circCEP85L对黄牛MuSCs增殖、凋亡及成肌分化的影响。【结果】PCR电泳结果证明circCEP85L环化位点真实存在。CircCEP85L在多种组织中表达,并在DM期的表达量显著高于GM期(P<0.001);为了进一步探究对circCEP85L黄牛MuSCs的影响。将过表达载体p-circCEP85L与对照载体pCD5-ciR转染体外培养的黄牛MuSCs,继续培养24 h之后,EdU结果表明过表达circCEP85L能显著降低EdU阳性细胞比例(P<0.001);流式周期检测结果表明,过表达circCEP85L增加了G0/G1期细胞比例,显著减少S期细胞比例(P<0.001);流式凋亡结果表明,过表达circCEP85L显著抑制MuSCs的凋亡率(P<0.05)。QRT-PCR及Western blot检测黄牛MuSCs增殖及凋亡相关基因的表达情况,结果表明过表达circCEP85L后显著降低了黄牛MuSCs增殖及凋亡相关基因的mRNA表达水平(P<0.001),凋亡蛋白BAX的表达量也显著降低(P<0.01)。此外,为了
