signal transduction

Signal Transduction
  • 文章类型: Journal Article
    背景:由于其独特的位置和多方面的代谢功能,心外膜脂肪组织(EAT)正逐步涌现为冠状动脉疾病风险分层的新代谢目标。微血管阻塞(MVO)已被认为是急性心肌梗死患者预后不良的独立危险因素。然而,EAT在ST段抬高型心肌梗死(STEMI)患者MVO形成发病机制中的具体作用尚不清楚.该研究的目的是评估STEMI患者通过心脏磁共振(CMR)测量的EAT积累与MVO形成之间的相关性,并阐明这种关系的潜在机制。
    方法:首先,我们利用CMR技术探讨了STEMI患者EAT分布和数量与MVO形成的关系.然后,我们利用EAT耗竭的小鼠模型来探索EAT如何在心肌缺血/再灌注(I/R)损伤的情况下影响MVO形成。我们通过共培养实验进一步研究了EAT对巨噬细胞的免疫调节作用。最后,我们寻找针对EAT的新治疗策略以防止MVO形成。
    结果:左房室EAT质量指数的增加与MVO形成独立相关。我们还发现DPP4的循环水平增加和高DPP4活性似乎与EAT增加有关。EAT积累作为促炎介质,通过分泌炎性EV促进巨噬细胞向心肌I/R损伤中的炎性表型转变。此外,我们的研究表明,GLP-1受体激动剂和GLP-1/GLP-2受体双重激动剂预防MVO的潜在治疗效果至少部分归因于其对EAT调节的影响.
    结论:我们的工作首次证明EAT的过度积累通过促进心肌巨噬细胞向炎症表型的极化状态促进MVO形成。此外,这项研究确定了一种非常有前途的治疗策略,GLP-1/GLP-2受体双激动剂,靶向EAT预防心肌I/R损伤后的MVO。
    BACKGROUND: Owing to its unique location and multifaceted metabolic functions, epicardial adipose tissue (EAT) is gradually emerging as a new metabolic target for coronary artery disease risk stratification. Microvascular obstruction (MVO) has been recognized as an independent risk factor for unfavorable prognosis in acute myocardial infarction patients. However, the concrete role of EAT in the pathogenesis of MVO formation in individuals with ST-segment elevation myocardial infarction (STEMI) remains unclear. The objective of the study is to evaluate the correlation between EAT accumulation and MVO formation measured by cardiac magnetic resonance (CMR) in STEMI patients and clarify the underlying mechanisms involved in this relationship.
    METHODS: Firstly, we utilized CMR technique to explore the association of EAT distribution and quantity with MVO formation in patients with STEMI. Then we utilized a mouse model with EAT depletion to explore how EAT affected MVO formation under the circumstances of myocardial ischemia/reperfusion (I/R) injury. We further investigated the immunomodulatory effect of EAT on macrophages through co-culture experiments. Finally, we searched for new therapeutic strategies targeting EAT to prevent MVO formation.
    RESULTS: The increase of left atrioventricular EAT mass index was independently associated with MVO formation. We also found that increased circulating levels of DPP4 and high DPP4 activity seemed to be associated with EAT increase. EAT accumulation acted as a pro-inflammatory mediator boosting the transition of macrophages towards inflammatory phenotype in myocardial I/R injury through secreting inflammatory EVs. Furthermore, our study declared the potential therapeutic effects of GLP-1 receptor agonist and GLP-1/GLP-2 receptor dual agonist for MVO prevention were at least partially ascribed to its impact on EAT modulation.
    CONCLUSIONS: Our work for the first time demonstrated that excessive accumulation of EAT promoted MVO formation by promoting the polarization state of cardiac macrophages towards an inflammatory phenotype. Furthermore, this study identified a very promising therapeutic strategy, GLP-1/GLP-2 receptor dual agonist, targeting EAT for MVO prevention following myocardial I/R injury.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:本研究的目的是评估在卵巢切除大鼠治疗高脂血症性骨质疏松中,去活肉芽胞苷调节PI3K/AKT信号通路的机制。
    方法:我们将无特异性病原体(SPF)大鼠随机分为五组(每组n=10)。正常对照组接受标准饮食,而模型组,阿托伐他汀组,己烯雌酚组,治疗组给予高脂饮食。四周后,进行了双侧卵巢切除术,其次是药物干预。经过6周的治疗,相关指标进行对比分析。
    结果:与正常对照组相比,模型组大鼠小梁形态模糊,杂乱无章的骨细胞,骨特异性碱性磷酸酶(BALP)水平显着升高,骨Gla蛋白(BGP),总胆固醇(TC),肿瘤坏死因子-α(TNF-α),和NF-κB受体激活剂配体(RANKL)。此外,模型组显示极限载荷水平显著降低,断裂载荷,雌二醇(E2),骨矿物质密度(BMD),骨保护素(OPG),股骨组织中的磷酸肌醇3-激酶(PI3K)和蛋白激酶B(Akt)。与正常对照组相比,阿托伐他汀组的TC和TNF-α水平更高。相反,治疗组表现出增强的小梁形态,更致密的结构,较小的骨髓腔,减少BALP,BGP,TC,TNF-α,和RANKL水平。此外,治疗组表现出更高水平的E2,BMD,OPG,骨组织中PI3K和Akt与模子组比拟。治疗组的TC和TNF-α水平也低于阿托伐他汀组。生物力学分析表明,在给药后,治疗组的体重减少,股骨的极限载荷和骨折载荷增加,更致密的骨骼结构,较小的骨髓腔,与模型组相比,骨膜排列改变。
    结论:我们的研究表明,露天莲在预防和治疗绝经后大鼠高脂血症性骨质疏松症方面具有显着的功效。
    BACKGROUND: To aim of this study is to assess the mechanism through which Desertliving Cistanche modulates the PI3K/AKT signaling pathway in the treatment of hyperlipidemic osteoporosis in ovariectomized rats.
    METHODS: We randomly assigned specific-pathogen-free (SPF) rats into five groups (n = 10 per group). The normal control group received a standard diet, while the model group, atorvastatin group, diethylstilbestrol group, and treatment group were fed a high-fat diet. Four weeks later, bilateral ovariectomies were conducted, followed by drug interventions. After six weeks of treatment, relevant indicators were compared and analyzed.
    RESULTS: Compared to the normal control group, rats in the model group exhibited blurred trabecular morphology, disorganized osteocytes, significantly elevated levels of bone-specific alkaline phosphatase (BALP), bone Gla-protein (BGP), total cholesterol (TC), tumor necrosis factor-α (TNF-α), and receptor activator of NF-κB ligand (RANKL). Also, the model group revealed significantly reduced levels of ultimate load, fracture load, estradiol (E2), bone mineral density (BMD), osteoprotegerin (OPG), and phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt) in femoral tissue. The atorvastatin group presented with higher TC and TNF-α levels compared to the normal control group. Conversely, the treatment group demonstrated enhanced trabecular morphology, denser structure, smaller bone marrow cavities, and reduced BALP, BGP, TC, TNF-α, and RANKL levels. Furthermore, the treatment group exhibited higher levels of E2, BMD, OPG, and PI3K and Akt in bone tissue compared to the model group. The treatment group also had lower TC and TNF-α levels than the atorvastatin group. Biomechanical analysis indicated that after administration of Desertliving Cistanche, the treatment group had reduced body mass, increased ultimate and fracture load of the femur, denser bone structure, smaller bone marrow cavities, and altered periosteal arrangement compared to the model group.
    CONCLUSIONS: Our study revealed that Desertliving Cistanche demonstrated significant efficacy in preventing and treating postmenopausal hyperlipidemic osteoporosis in rats.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    目的:PD-1/PD-L1抑制剂已成为一种有前途的治疗方法。然而,宫颈癌(CC)患者的反应率低于30%,这与肿瘤微环境(TME)中的免疫抑制成分有关。肿瘤相关巨噬细胞(TAMs),作为最重要的免疫细胞之一,参与肿瘤抑制微环境的形成。因此,研究TAMs对PD-L1表达的调控机制,为提高疗效提供理论依据。
    方法:收集CC患者的临床资料和病理组织,免疫组化检测PD-L1、CD68和CD163的表达。生物信息学分析参与PD-L1调控的巨噬细胞亚型。建立共培养模型,观察TAMs对其形态学的影响,CC细胞的迁移和侵袭功能,以及TAMs对PD-L1的调控机制。
    结果:PD-L1在肿瘤细胞上的表达可以预测患者的不良预后。PD-L1的表达与CD163+TAMs的浸润有很强的相关性。同样,生物信息学分析中PD-L1表达与M1/M2型TAMs浸润相关。细胞共培养结果显示M1/M2型TAMs能上调PD-L1的表达,特别是M2型TAM可能通过PI3K/AKT途径提高PD-L1的表达。同时,M1/M2型TAM可以影响形态变化,增强CC细胞的迁移和侵袭能力。
    结论:PD-L1在肿瘤细胞中的表达可作为预后因素,且与CD163+TAMs浸润密切相关。此外,M2型TAMs可通过PI3K/AKT通路上调CC细胞PD-L1表达,增强迁移和入侵能力,并影响肿瘤进展。
    OBJECTIVE: PD-1/PD-L1 inhibitors have become a promising therapy. However, the response rate is lower than 30% in patients with cervical cancer (CC), which is related to immunosuppressive components in tumor microenvironment (TME). Tumor-associated macrophages (TAMs), as one of the most important immune cells, are involved in the formation of tumor suppressive microenvironment. Therefore, it will provide a theoretical basis for curative effect improvement about the regulatory mechanism of TAMs on PD-L1 expression.
    METHODS: The clinical data and pathological tissues of CC patients were collected, and the expressions of PD-L1, CD68 and CD163 were detected by immunohistochemistry. Bioinformatics was used to analyze the macrophage subtypes involved in PD-L1 regulation. A co-culture model was established to observe the effects of TAMs on the morphology, migration and invasion function of CC cells, and the regulatory mechanism of TAMs on PD-L1.
    RESULTS: PD-L1 expression on tumor cells could predict the poor prognosis of patients. And there was a strong correlation between PD-L1 expression with CD163+TAMs infiltration. Similarly, PD-L1 expression was associated with M1/M2-type TAMs infiltration in bioinformatics analysis. The results of cell co-culture showed that M1/M2-type TAMs could upregulate PD-L1 expression, especially M2-type TAMs may elevate the PD-L1 expression via PI3K/AKT pathway. Meanwhile, M1/M2-type TAMs can affect the morphological changes, and enhance migration and invasion abilities of CC cells.
    CONCLUSIONS: PD-L1 expression in tumor cells can be used as a prognostic factor and is closely related to CD163+TAMs infiltration. In addition, M2-type TAMs can upregulate PD-L1 expression in CC cells through PI3K/AKT pathway, enhance the migration and invasion capabilities, and affect the tumor progression.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:糖尿病性白内障(DC)是糖尿病的常见并发症,其病因和进展是多因素的。在这项研究中,探讨了特异性蛋白1(SP1)和成纤维细胞生长因子7(FGF7)在DC发育中的作用。
    方法:用高糖处理SRA01/04细胞建立DC细胞模型。进行MTT测定以评估细胞活力。进行Transwell测定和伤口愈合测定以评估细胞迁移和侵袭。Westernblot和qRT-PCR检测N-cadherin的表达,E-cadherin,胶原蛋白I,纤连蛋白,SP1和FGF7表达。进行CHIP测定和双荧光素酶报告基因测定以分析FGF7和SP1之间的组合。
    结果:FGF7在DC患者和HG诱导的SRA01/04细胞中上调。HG处理促进SRA01/04细胞活力,迁移,侵袭和上皮间质转化(EMT),而FGF7敲除减轻了影响。转录因子SP1激活了FGF7的转录水平,SP1过表达加重了HG诱导的SRA01/04细胞损伤。SP1沉默抑制了HG诱导的SRA01/04细胞活力,迁移,入侵和EMT,但这些影响通过上调FGF7得到改善。此外,SP1敲低通过调节FGF7的转录水平抑制PI3K/AKT通路。
    结论:转录因子SP1激活FGF7的转录水平和PI3K/AKT通路,调节HG诱导的SRA01/04细胞活力,迁移,入侵和EMT。
    BACKGROUND: Diabetic cataract (DC) is a common complication of diabetes and its etiology and progression are multi-factorial. In this study, the roles of specific protein 1 (SP1) and fibroblast growth factor 7 (FGF7) in DC development were explored.
    METHODS: DC cell model was established by treating SRA01/04 cells with high glucose (HG). MTT assay was conducted to evaluate cell viability. Transwell assay and wound-healing assay were performed to assess cell migration and invasion. Western blot assay and qRT-PCR assay were conducted to measure the expression of N-cadherin, E-cadherin, Collagen I, Fibronectin, SP1 and FGF7 expression. CHIP assay and dual-luciferase reporter assay were conducted to analyze the combination between FGF7 and SP1.
    RESULTS: FGF7 was upregulated in DC patients and HG-induced SRA01/04 cells. HG treatment promoted SRA01/04 cell viability, migration, invasion and epithelial-mesenchymal transition (EMT), while FGF7 knockdown abated the effects. Transcription factor SP1 activated the transcription level of FGF7 and SP1 overexpression aggravated HG-induced SRA01/04 cell injury. SP1 silencing repressed HG-induced SRA01/04 cell viability, migration, invasion and EMT, but these effects were ameliorated by upregulating FGF7. Additionally, SP1 knockdown inhibited the PI3K/AKT pathway by regulating the transcription level of FGF7.
    CONCLUSIONS: Transcription factor SP1 activated the transcription level of FGF7 and the PI3K/AKT pathway to regulate HG-induced SRA01/04 cell viability, migration, invasion and EMT.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:Ubiquilin-4(UBQLN4),ubiquilin家族的一员,迄今为止,在癌症研究中受到的关注有限。这里,我们首次研究了UBQLN4在非小细胞肺癌(NSCLC)中的功能作用和机制。
    方法:使用癌症基因组图谱(TCGA)数据库来验证UBQLN4作为差异表达基因。使用免疫组织化学(IHC)实验和蛋白质印迹(WB)实验评估UBQLN4在NSCLC细胞和组织中的表达差异。进行Kaplan-Meier分析以检查UBQLN4表达与NSCLC预后之间的关联。通过细胞计数试剂盒-8(CCK-8)进行UBQLN4的功能分析,菌落形成,和transwell入侵测定。使用路径扫描细胞内信号传导阵列评估UBQLN4对肿瘤相关信号传导途径的影响。进行体内肿瘤发生实验以进一步研究UBQLN4对肿瘤形成的影响。
    结果:UBQLN4在NSCLC组织和细胞中均表现出上调。此外,UBQLN4的过表达与NSCLC患者的不良预后相关.功能丧失分析表明,抑制UBQLN4可以在体外和体内环境中抑制NSCLC细胞的增殖和侵袭。相反,功能增益实验产生了相反的结果。路径扫描细胞内信号阵列结果表明,UBQLN4的作用与PI3K/AKT通路有关,通过体外和体内肿瘤发生实验证实的相关性。
    结论:我们验证了UBQLN4通过激活PI3K/AKT通路促进NSCLC细胞增殖和侵袭,从而促进NSCLC的进展。这些发现强调了靶向UBQLN4作为NSCLC治疗策略的潜力。
    BACKGROUND: Ubiquilin-4 (UBQLN4), a member of the ubiquilin family, has received limited attention in cancer research to date. Here, we investigated for the first time the functional role and mechanism of UBQLN4 in non-small cell lung cancer (NSCLC).
    METHODS: The Cancer Genome Atlas (TCGA) database was employed to validate UBQLN4 as a differentially expressed gene. Expression differences of UBQLN4 in NSCLC cells and tissues were assessed using immunohistochemistry (IHC) experiment and western blotting (WB) experiment. Kaplan-Meier analysis was conducted to examine the association between UBQLN4 expression and NSCLC prognosis. Functional analyses of UBQLN4 were performed through cell counting kit-8 (CCK-8), colony formation, and transwell invasion assays. The impact of UBQLN4 on tumor-associated signaling pathways was assessed using the path scan intracellular signaling array. In vivo tumorigenesis experiments were conducted to further investigate the influence of UBQLN4 on tumor formation.
    RESULTS: UBQLN4 exhibited up-regulation in both NSCLC tissues and cells. Additionally, over-expression of UBQLN4 was associated with an unfavorable prognosis in NSCLC patients. Functional loss analyses demonstrated that inhibiting UBQLN4 could suppress the proliferation and invasion of NSCLC cells in both in vitro and in vivo settings. Conversely, functional gain experiments yielded opposite results. Path scan intracellular signaling array results suggested that the role of UBQLN4 is associated with the PI3K/AKT pathway, a correlation substantiated by in vitro and in vivo tumorigenesis experiments.
    CONCLUSIONS: We validated that UBQLN4 promotes proliferation and invasion of NSCLC cells by activating the PI3K/AKT pathway, thereby facilitating the progression of NSCLC. These findings underscore the potential of targeting UBQLN4 as a therapeutic strategy for NSCLC.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    本文回顾了细胞周期计算模型的最新知识和最新进展。它提供了各种建模范式的比较分析,突出他们的独特优势,局限性,和应用。具体来说,本文比较了确定性模型和随机性模型,单细胞与种群模型,以及机械模型和抽象模型。这种详细分析有助于为各种研究需求确定最合适的建模框架。此外,讨论扩展到利用这些计算模型来阐明细胞周期动力学,特别关注细胞周期活力,与信号通路的串扰,肿瘤微环境,DNA复制,和修复机制,强调它们在肿瘤进展和癌症治疗优化中的关键作用。通过将这些模型应用于癌症治疗计划的关键方面,以获得更好的结果,包括药物功效量化,药物发现,耐药性分析,和剂量优化,该综述强调了计算见解在提高癌症治疗的精确性和有效性方面的巨大潜力.这种对计算建模和治疗策略开发之间复杂关系的强调强调了先进的建模技术在导航细胞周期动力学的复杂性及其对癌症治疗的影响方面的关键作用。
    This article reviews the current knowledge and recent advancements in computational modeling of the cell cycle. It offers a comparative analysis of various modeling paradigms, highlighting their unique strengths, limitations, and applications. Specifically, the article compares deterministic and stochastic models, single-cell versus population models, and mechanistic versus abstract models. This detailed analysis helps determine the most suitable modeling framework for various research needs. Additionally, the discussion extends to the utilization of these computational models to illuminate cell cycle dynamics, with a particular focus on cell cycle viability, crosstalk with signaling pathways, tumor microenvironment, DNA replication, and repair mechanisms, underscoring their critical roles in tumor progression and the optimization of cancer therapies. By applying these models to crucial aspects of cancer therapy planning for better outcomes, including drug efficacy quantification, drug discovery, drug resistance analysis, and dose optimization, the review highlights the significant potential of computational insights in enhancing the precision and effectiveness of cancer treatments. This emphasis on the intricate relationship between computational modeling and therapeutic strategy development underscores the pivotal role of advanced modeling techniques in navigating the complexities of cell cycle dynamics and their implications for cancer therapy.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    越来越多的证据支持细胞竞争,多细胞生物中至关重要的选择和质量控制机制,参与肿瘤发生和发展;然而,细胞竞争与肿瘤耐药性之间的相关机制贡献仍不明确.在我们的研究中,基于对列维替尼耐药的肝细胞癌(HCC)细胞通过重编程能量代谢显示出明显的竞争生长优势。机械上,Lenvatinib耐药HCC细胞中BCL2相互作用蛋白3(BNIP3)介导的线粒体自噬的过度激活通过将能量产生从线粒体氧化磷酸化转移到糖酵解来促进糖酵解通量,通过调节AMP激活的蛋白激酶(AMPK)-烯醇化酶2(ENO2)信号,永久保持耐乐替尼肝癌细胞相对于敏感肝癌细胞的竞争优势。值得注意的是,BNIP3抑制显著敏化乐伐替尼在HCC中的抗肿瘤功效。我们的发现强调了BNIP3-AMPK-ENO2信号传导在通过调节能量代谢重编程维持耐来维替尼肝癌细胞的竞争性结果中的重要作用;同时,这项工作认为BNIP3是克服HCC耐药性的有希望的靶标。
    An increasing evidence supports that cell competition, a vital selection and quality control mechanism in multicellular organisms, is involved in tumorigenesis and development; however, the mechanistic contributions to the association between cell competition and tumor drug resistance remain ill-defined. In our study, based on a contructed lenvitinib-resistant hepatocellular carcinoma (HCC) cells display obvious competitive growth dominance over sensitive cells through reprogramming energy metabolism. Mechanistically, the hyperactivation of BCL2 interacting protein3 (BNIP3) -mediated mitophagy in lenvatinib-resistant HCC cells promotes glycolytic flux via shifting energy production from mitochondrial oxidative phosphorylation to glycolysis, by regulating AMP-activated protein kinase (AMPK) -enolase 2 (ENO2) signaling, which perpetually maintaining lenvatinib-resistant HCC cells\' competitive advantage over sensitive HCC cells. Of note, BNIP3 inhibition significantly sensitized the anti-tumor efficacy of lenvatinib in HCC. Our findings emphasize a vital role for BNIP3-AMPK-ENO2 signaling in maintaining the competitive outcome of lenvitinib-resistant HCC cells via regulating energy metabolism reprogramming; meanwhile, this work recognizes BNIP3 as a promising target to overcome HCC drug resistance.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    肝功能衰竭和肝硬化的特征是异常止血和异常血小板活化。特别是,胆汁淤积性肝病的后果和分子机制,包括胆汁酸导致血小板反应受损的作用,不是很了解。这里,我们证明胆汁酸抑制人和鼠的血小板活化,粘附和扩散,导致流动条件下血栓形成减少。我们鉴定了血小板中的G蛋白偶联受体TGR5,并为其作为胆汁酸诱导的血小板活化受损的介质的作用提供了支持。在肝脏中,TGR5与Gαs蛋白配对,激活腺苷酸环化酶诱导短暂的cAMP升高,刺激MAPK信号通路调节胆管细胞增殖,肝细胞存活和炎症。在这份报告中,我们证明TGR5的遗传缺陷导致小鼠血小板活化和血栓形成增强,提示TGR5在止血中起重要作用。机械上,血小板抑制是通过TGR5介导的PKA激活和AKT和ERK1/2磷酸化的调节实现的。因此,本报告为TGR5配体降低血小板活化的能力提供了证据,并将TGR5激动作用确定为预防心血管疾病的新靶点.
    背景是什么?肝功能衰竭或肝硬化与止血受损有关,胆汁酸在血小板反应受损中的作用是已知的,但知之甚少。血小板表达胆汁酸受体FXR。与血小板上的FXR结合的配体引起血小板反应性的转变并且是动脉粥样硬化保护性的,表明FXR是预防动脉粥样硬化血栓性疾病的潜在靶标。什么是新的?用低分子量的胆汁酸治疗鼠和人血液导致血小板活化降低,粘连和血栓形成。在人和鼠血小板上鉴定了胆汁酸受体TGR5。TGR5在止血中起重要作用,因为TGR5缺陷小鼠显示出升高的血小板反应性和增强的血栓形成。TGR5的缺失导致增强的PKA活化并调节MAPK如AKT和ERK1/2的磷酸化。有什么影响?胆汁酸对血小板活化的损害是由TGR5通过蛋白激酶A信号通路介导的。我们的发现为TGR5激活作为两者的潜在新靶标的调节提供了证据,抗血小板治疗在心血管疾病和肝损伤后恢复止血。
    Liver failure and cirrhosis are characterized by abnormal hemostasis with aberrant platelet activation. In particular, the consequences of cholestatic liver disease and molecular mechanisms, including the role of bile acids leading to impaired platelet responses, are not well understood. Here, we demonstrate that bile acids inhibit human and murine platelet activation, adhesion and spreading, leading to reduced thrombus formation under flow conditions. We identified the G-protein coupled receptor TGR5 in platelets and provide support for its role as mediator of bile acid-induced impairment of platelet activation. In the liver, TGR5 couples to Gαs proteins, activates the adenylate cyclase to induce a transient cAMP rise and stimulates the MAPK signaling pathway to regulate cholangiocyte proliferation, hepatocyte survival and inflammation. In this report, we demonstrate that the genetic deficiency of TGR5 in mice led to enhanced platelet activation and thrombus formation, suggesting that TGR5 plays an important role in hemostasis. Mechanistically, platelet inhibition is achieved by TGR5 mediated PKA activation and modulation of AKT and ERK1/2 phosphorylation. Thus, this report provides evidence for the ability of TGR5 ligands to reduce platelet activation and identifies TGR5 agonism as a new target for the prevention of cardiovascular diseases.
    What is the context? Liver failure or cirrhosis are related to impaired hemostasis and a role of bile acids in impaired platelet responses is known but only less understood.Platelets express the bile acid receptor FXR. Ligand binding to the FXR on platelets causes a shift in platelet reactivity and is atheroprotective suggesting that the FXR is a potential target for the prevention of atherothrombotic diseases.What is new? Treatment of murine and human blood with bile acids in low molecular quantity led to reduced platelet activation, adhesion and thrombus formation.The bile acid receptor TGR5 was identified on human and murine platelets.TGR5 plays an important role in hemostasis because TGR5 deficient mice showed elevated platelet reactivity and enhanced thrombus formation.Loss of TGR5 led to enhanced PKA activation and modulated the phosphorylation of MAPK such as AKT and ERK1/2.What is the impact? Impairment of platelet activation by bile acids is mediated by TGR5 via the protein kinase A signaling pathway.Our findings provide evidence for the modulation of TGR5 activation as a potential new target of both, anti-platelet therapy in cardiovascular diseases and the restoration of hemostasis upon liver injury.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    几十年前,观察到有丝分裂原促进的信号传导持续时间和强度被细胞感知,并且对于其决定:增殖或分化至关重要。具有里程碑意义的出版物不仅在G1细胞周期阶段而且在S和G2/M过渡中确立了丝裂原信号传导的重要性。尽管有这些早期的里程碑,丝裂原信号的持续时间和强度,短而强,弱而持续,控制细胞的命运在很大程度上没有受到重视。这里,我们以基本信号相关的问题为中心,包括(i)波动的有丝分裂信号如何转化为细胞增殖-分化决定,以及(ii)为什么延长的弱信号持续时间与分化有关,虽然强和短的爆发诱导增殖,但是,如果太强大和漫长,诱导不可逆衰老。我们创新的广阔前景利用细胞生物学和蛋白质构象集合,帮助我们定义信号强度,阐明细胞周期决定,从而细胞命运。
    Decades ago, mitogen-promoted signaling duration and strength were observed to be sensed by the cell and to be critical for its decisions: to proliferate or differentiate. Landmark publications established the importance of mitogen signaling not only in the G1 cell cycle phase but also through the S and the G2/M transition. Despite these early milestones, how mitogen signal duration and strength, short and strong or weaker and sustained, control cell fate has been largely unheeded. Here, we center on cardinal signaling-related questions, including (i) how fluctuating mitogenic signals are converted into cell proliferation-differentiation decisions and (ii) why extended duration of weak signaling is associated with differentiation, while bursts of strong and short induce proliferation but, if too strong and long, induce irreversible senescence. Our innovative broad outlook harnesses cell biology and protein conformational ensembles, helping us to define signaling strength, clarify cell cycle decisions, and thus cell fate.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在血管生成过程中,血管尖细胞引导新生的血管芽形成血管网。Apelin,G蛋白偶联受体Aplnr的激动剂,富含血管尖端细胞,据推测,血管来源的Apelin调节发芽血管生成。我们在背侧神经管中鉴定了表达apelin的神经祖细胞群。血管尖端细胞表现出朝向和沿着表达apelin的神经祖细胞的定向伸长和迁移。值得注意的是,在apelin突变体中恢复神经而不是血管apelin表达可以弥补突变体的血管生成缺陷。通过功能分析,我们展示了Apelin信号传导对尖端细胞行为的需求,比如丝足形成和细胞伸长。通过遗传相互作用研究和转基因活性报告基因分析,我们确定Apelin信号是体内tip细胞中磷酸肌醇3激酶和细胞外信号调节激酶信号的调节剂。我们的结果表明,由Apelin信号介导的先前未发现的神经血管串扰,这对于发芽血管生成期间的尖端细胞功能很重要。
    During angiogenesis, vascular tip cells guide nascent vascular sprouts to form a vascular network. Apelin, an agonist of the G protein-coupled receptor Aplnr, is enriched in vascular tip cells, and it is hypothesized that vascular-derived Apelin regulates sprouting angiogenesis. We identify an apelin-expressing neural progenitor cell population in the dorsal neural tube. Vascular tip cells exhibit directed elongation and migration toward and along the apelin-expressing neural progenitor cells. Notably, restoration of neural but not vascular apelin expression in apelin mutants remedies the angiogenic defects of mutants. By functional analyses, we show the requirement of Apelin signaling for tip cell behaviors, like filopodia formation and cell elongation. Through genetic interaction studies and analysis of transgenic activity reporters, we identify Apelin signaling as a modulator of phosphoinositide 3-kinase and extracellular signal-regulated kinase signaling in tip cells in vivo. Our results suggest a previously unidentified neurovascular cross-talk mediated by Apelin signaling that is important for tip cell function during sprouting angiogenesis.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号