Skeletal muscles are essential for locomotion,posture,and metabolic regulation.To understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways...Skeletal muscles are essential for locomotion,posture,and metabolic regulation.To understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways that underlie skeletal muscle function.The process of muscle contra ction,orchestrated by a complex interplay of molecular events,is at the core of skeletal muscle function.Muscle contraction is initiated by an action potential and neuromuscular transmission requiring a neuromuscular junction.Within muscle fibers,calcium ions play a critical role in mediating the interaction between actin and myosin filaments that generate force.Regulation of calcium release from the sarcoplasmic reticulum plays a key role in excitation-contraction coupling.The development and growth of skeletal muscle are regulated by a network of molecular pathways collectively known as myogenesis.Myogenic regulators coordinate the diffe rentiation of myoblasts into mature muscle fibers.Signaling pathways regulate muscle protein synthesis and hypertrophy in response to mechanical stimuli and nutrient availability.Seve ral muscle-related diseases,including congenital myasthenic disorders,sarcopenia,muscular dystrophies,and metabolic myopathies,are underpinned by dys regulated molecular pathways in skeletal muscle.Therapeutic interventions aimed at preserving muscle mass and function,enhancing regeneration,and improving metabolic health hold promise by targeting specific molecular pathways.Other molecular signaling pathways in skeletal muscle include the canonical Wnt signaling pathway,a critical regulator of myogenesis,muscle regeneration,and metabolic function,and the Hippo signaling pathway.In recent years,more details have been uncovered about the role of these two pathways during myogenesis and in developing and adult skeletal muscle fibers,and at the neuromuscular junction.In fact,research in the last few years now suggests that these two signaling pathways are interconnected and that they jointly control physiological and pat展开更多
Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significa...Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC.Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network.Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein(YAP) and WW-domaincontaining transcriptional co-activator with PDZ-binding motif(TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.展开更多
目的探讨姜黄素对B细胞淋巴瘤细胞系Raji细胞转录共激活因子P300的影响及对Raji细胞的作用及其机制。方法以不同浓度的姜黄素作用于体外培养Raji细胞,MTT法检测细胞生长抑制率,应用RT-PCR和蛋白印迹(W estern b lot)法检测Raji细胞中P30...目的探讨姜黄素对B细胞淋巴瘤细胞系Raji细胞转录共激活因子P300的影响及对Raji细胞的作用及其机制。方法以不同浓度的姜黄素作用于体外培养Raji细胞,MTT法检测细胞生长抑制率,应用RT-PCR和蛋白印迹(W estern b lot)法检测Raji细胞中P300的表达。结果①姜黄素具有明显的抑制Raji细胞生长作用,并呈明显的量效关系。②姜黄素作用24 h后,随着浓度剂量的增加P300的mRNA和蛋白表达而逐渐降低。低剂量(6.25μmol.L-1)组P300表达有一定的降低,但与对照组相比差异无显著性(P>0.05),而中、高剂量(12.5、25及50μmol.L-1)则抑制P300的表达(P<0.05)。结论姜黄素对B细胞淋巴瘤细胞系Raji细胞具有抗肿瘤细胞的增殖作用,并呈浓度依赖性。姜黄素能够抑制转录共激活因子P300的表达,可能是其重要的机制。展开更多
目的探讨高氧致新生大鼠慢性肺损伤中PDZ结合基序转录共激活因子(transcriptional co-activator with PDZ-binding motif,TAZ)的表达及其作用。方法建立新生大鼠高氧致肺损伤模型,实验组和对照组分别吸入氧气(85%)和空气。分别在第1、3...目的探讨高氧致新生大鼠慢性肺损伤中PDZ结合基序转录共激活因子(transcriptional co-activator with PDZ-binding motif,TAZ)的表达及其作用。方法建立新生大鼠高氧致肺损伤模型,实验组和对照组分别吸入氧气(85%)和空气。分别在第1、3、7、14、21天留取肺组织,肺组织切片苏木精-伊红染色观察肺组织病理改变,应用实时荧光定量聚合酶链式反应、Western blot和免疫组织化学技术检测肺组织中TAZ、表面活性蛋白C(surfactant protein C,SPC)、水通道蛋白5(aquaporin-5,AQP5)蛋白的动态表达情况。结果实验组肺组织逐渐出现肺泡间隔增厚,肺泡棘消失,肺泡腔增大,数目减少,肺泡结构简单化。与对照组相比,实验组肺组织中第1、3天TAZ、SPC、AQP5表达无差异(P>0.05);第7、14、21天实验组肺组织中TAZ的mRNA和蛋白表达明显降低,SPC的mRNA和蛋白表达明显升高,而AQP5的mRNA和蛋白表达量下降,差异均有统计学意义(P<0.05)。结论高氧可致新生大鼠肺泡结构紊乱和肺发育停滞;由SPC、AQP5表达结果说明Ⅰ型肺泡上皮细胞损伤严重,Ⅱ型肺泡上皮细胞虽然数量有所增加但其分化能力明显下降,而TAZ表达量减少可能致使大量的Ⅱ型肺泡上皮细胞失去了分化为Ⅰ型肺泡上皮细胞的功能。展开更多
基金supported by the German Research Council(Deutsche Forschungsgemeinschaft,HA3309/3-1/2,HA3309/6-1,HA3309/7-1)。
文摘Skeletal muscles are essential for locomotion,posture,and metabolic regulation.To understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways that underlie skeletal muscle function.The process of muscle contra ction,orchestrated by a complex interplay of molecular events,is at the core of skeletal muscle function.Muscle contraction is initiated by an action potential and neuromuscular transmission requiring a neuromuscular junction.Within muscle fibers,calcium ions play a critical role in mediating the interaction between actin and myosin filaments that generate force.Regulation of calcium release from the sarcoplasmic reticulum plays a key role in excitation-contraction coupling.The development and growth of skeletal muscle are regulated by a network of molecular pathways collectively known as myogenesis.Myogenic regulators coordinate the diffe rentiation of myoblasts into mature muscle fibers.Signaling pathways regulate muscle protein synthesis and hypertrophy in response to mechanical stimuli and nutrient availability.Seve ral muscle-related diseases,including congenital myasthenic disorders,sarcopenia,muscular dystrophies,and metabolic myopathies,are underpinned by dys regulated molecular pathways in skeletal muscle.Therapeutic interventions aimed at preserving muscle mass and function,enhancing regeneration,and improving metabolic health hold promise by targeting specific molecular pathways.Other molecular signaling pathways in skeletal muscle include the canonical Wnt signaling pathway,a critical regulator of myogenesis,muscle regeneration,and metabolic function,and the Hippo signaling pathway.In recent years,more details have been uncovered about the role of these two pathways during myogenesis and in developing and adult skeletal muscle fibers,and at the neuromuscular junction.In fact,research in the last few years now suggests that these two signaling pathways are interconnected and that they jointly control physiological and pat
文摘Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC.Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network.Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein(YAP) and WW-domaincontaining transcriptional co-activator with PDZ-binding motif(TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.
文摘目的探讨姜黄素对B细胞淋巴瘤细胞系Raji细胞转录共激活因子P300的影响及对Raji细胞的作用及其机制。方法以不同浓度的姜黄素作用于体外培养Raji细胞,MTT法检测细胞生长抑制率,应用RT-PCR和蛋白印迹(W estern b lot)法检测Raji细胞中P300的表达。结果①姜黄素具有明显的抑制Raji细胞生长作用,并呈明显的量效关系。②姜黄素作用24 h后,随着浓度剂量的增加P300的mRNA和蛋白表达而逐渐降低。低剂量(6.25μmol.L-1)组P300表达有一定的降低,但与对照组相比差异无显著性(P>0.05),而中、高剂量(12.5、25及50μmol.L-1)则抑制P300的表达(P<0.05)。结论姜黄素对B细胞淋巴瘤细胞系Raji细胞具有抗肿瘤细胞的增殖作用,并呈浓度依赖性。姜黄素能够抑制转录共激活因子P300的表达,可能是其重要的机制。
文摘目的探讨高氧致新生大鼠慢性肺损伤中PDZ结合基序转录共激活因子(transcriptional co-activator with PDZ-binding motif,TAZ)的表达及其作用。方法建立新生大鼠高氧致肺损伤模型,实验组和对照组分别吸入氧气(85%)和空气。分别在第1、3、7、14、21天留取肺组织,肺组织切片苏木精-伊红染色观察肺组织病理改变,应用实时荧光定量聚合酶链式反应、Western blot和免疫组织化学技术检测肺组织中TAZ、表面活性蛋白C(surfactant protein C,SPC)、水通道蛋白5(aquaporin-5,AQP5)蛋白的动态表达情况。结果实验组肺组织逐渐出现肺泡间隔增厚,肺泡棘消失,肺泡腔增大,数目减少,肺泡结构简单化。与对照组相比,实验组肺组织中第1、3天TAZ、SPC、AQP5表达无差异(P>0.05);第7、14、21天实验组肺组织中TAZ的mRNA和蛋白表达明显降低,SPC的mRNA和蛋白表达明显升高,而AQP5的mRNA和蛋白表达量下降,差异均有统计学意义(P<0.05)。结论高氧可致新生大鼠肺泡结构紊乱和肺发育停滞;由SPC、AQP5表达结果说明Ⅰ型肺泡上皮细胞损伤严重,Ⅱ型肺泡上皮细胞虽然数量有所增加但其分化能力明显下降,而TAZ表达量减少可能致使大量的Ⅱ型肺泡上皮细胞失去了分化为Ⅰ型肺泡上皮细胞的功能。
