内质网应激与细胞凋亡

内质网(ER)是细胞内重要的细胞器,参与多种细胞进程,这些进程对于维持细胞存活和发挥细胞的正常生理功能具有重要的作用。然而在多种生理病理条件下,内质网稳态会发生变化而失衡,从而诱发内质网应激(ERS),此时机体通过激活未折叠蛋白反应(UPR)来恢复内质网的正常功能。当持续的ERS状态无法恢复时,ERS就会触发细胞凋亡程序,通过不同的凋亡途径引起细胞凋亡。     

内质网应激与膜性肾病

内质网(endoplasmic reticulum,ER)是调节蛋白质合成、折叠及组装的重要场所。各种原因如ER中Ca2+缺乏均可引起ER功能紊乱,使蛋白质从ER向高尔基体的转运受阻[1],最终引发内质网应激(endoplasmic reticulum stress,ERS)。细胞通过激活未折叠蛋白反应(the unfolded protein response,UPR)保护ERS引起损伤的细胞,强烈或持久的ERS又可启动UPR的促凋亡信号。肾病尤其是膜性肾病(membranous nephropathy,MN)的发生发展与ERS密切相关,文中主要阐述ERS在MN发病机制中的作用。     

内质网应激及其与肿瘤能量代谢关系的研究进展

内质网具有多种功能,当其稳态发生失衡时,便会发生内质网应激(endoplasmic reticulum stress,ERS).内质网会启动名为未折叠蛋白应答(unfolded protein response,UPR)的高度调节机制,保护细胞免受错误折叠蛋白的积累.肿瘤代谢与ERS有着密不可分的联系,多种人类肿瘤中都...     

内质网应激与血管内皮细胞凋亡的研究进展

内质网应激(ERS)凋亡途径是继死亡受体信号途径和线粒体途径后发现的一种新的细胞凋亡途径。虽然该途径早期通过激活未折叠蛋白反应使细胞内蛋白质合成暂停、内质网稳态恢复,起到细胞保护作用,但当机体诱导ERS的因素持续存在,ERS也将持续进行,并会触发C/EBP同源蛋白、c-JUN氨基末端激酶及caspase等通路诱导细胞凋亡。血管内皮细胞损伤及凋亡是各种疾病和病理生理过程的重要环节,大量研究表明,血管内皮细胞凋亡与ERS密切相关,通过干预ERS可以有效对抗其凋亡,起到保护血管内皮的作用。本文总结了ERS及其参与血管内皮细胞凋亡机制的研究进展。     

内质网应激中ATF-6调控细胞凋亡及相关疾病

许多异常反应都会引起内质网应激,进而激活未折叠蛋白反应。当未折叠反应仍不能缓解内质网蛋白负荷时,就会通过多条途径引起细胞凋亡,并引起相关疾病,如糖尿病,躁郁症,神经退行性疾病和创伤后应激反应PTSD等。该文主要论述活化转录因子6在ER应激中调控细胞凋亡的机制以及引起的相关疾病。     

内质网应激在肝脏疾病中的研究进展

大量研究证实内质网应激（ERS）与肝脏疾病的发生、发展密切相关,但ERS与肝脏疾病进展的关联机制目前尚未明确,还需进一步探索。诸多研究发现,适度的ERS能激活未折叠蛋白反应（UPR）以保护细胞,而严重或持续的ERS将诱导细胞凋亡。因此,探讨ERS在肝脏疾病发病机制中的作用可能有助于发现新的治疗策略。故本文就ERS和UPR在多种肝脏疾病中的研究现状及其潜在治疗策略进行阐述。     

钙调蛋白介导内质网应激相关自噬促进肌修复

摘要:目的 探究钙调蛋白在骨骼肌损伤内质网应激相关性自噬中的作用及机制。方法 制备小鼠肌损伤内质网 应激(ERS)模型,采用钙调蛋白激动剂/拮抗剂干扰该信号;同时体外以衣霉素化学诱导 C2C12细胞分化的肌管发生 ERS,继而添加钙调蛋白干扰剂刺激。检测未折叠蛋白反应(UPR)标志物 mRNA 和 UPR通路关键分子蛋白表达水平, 以及 ERS诱导自噬相关蛋白的表达。结果 肌损伤后,肌内 UPR标志物(BiP、XBP1-S和 ATF6)mRNA 显著上调(P< 0.05),ERS激活的 UPR关键通路分子eIF2α、IRE1α和 ATF6蛋白活性显著上调(均 P<0.05),自噬标志物 LC3Ⅱ/Ⅰ 增加,采用钙调蛋白激动剂 CALP1可增强此反应。结论 钙调蛋白参与了未折叠蛋白反应,并可能通过调节 ERS相关 性自噬促进骨骼肌损伤修复过程。     

内质网应激与胰岛素抵抗和糖尿病的发生

ERS（endoplasmic reticulum stress,ERS）在多种疾病如糖尿病、心血管疾病等的发病中起着重要的作用。当发生ERS时,细胞启动未折叠蛋白反应（unfolded protein response ,UPR）以减轻ERS,保护细胞。在胰岛中,如果细胞持续发生ERS,UPR反应不能保护细胞时,反而可激活细胞凋亡通路,引起胰岛细胞凋亡。当外周胰岛素敏感组织如肝、肌肉、脂肪组织等发生ERS时可导致细胞出现胰岛素抵抗（Insulin resistance ,IR）。针对ERS反应的关键信号通路,可以开发相关的药物,以减轻IR。预防和治疗糖尿病。     

内质网应激与阿尔茨海默病

内质网(endoplasmic reticulum, ER)是细胞参与蛋白质翻译后的修饰、折叠和寡聚化,还参与钙的储存、脂质代谢和类固醇激素的合成,ER中钙离子紊乱和未折叠蛋白质蓄积可引发内质网应激(endoplasmic reticulum stress,ERS),发生具有保护作用的未折叠蛋白反应,而长期过强的ERS或ERS机制失常将诱导细胞凋亡.阿尔茨海默病(Alzheimer's disease, AD)是一种常见的神经系统变性疾病,最近的研究表明AD与ER的功能障碍有关.深入研究ERS将为进一步探索AD的发病机制和治疗方案开辟新的思路.     

内质网应激在神经元退行性变性中作用的研究进展

内质网是细胞折叠加工蛋白和储存钙的主要场所,当内质网功能受损,即处于内质网应激(endoplasmic reticulum stress,ERS)状态时,非折叠蛋白在内质网腔内堆积,形成潜在的毒性聚集.为了恢复内质网功能,细胞将启动一系列的应激反应,其中一个最重要的应激反应就是非折叠蛋白应答(unfolded protein response,UPR).     

内质网应激与支气管哮喘

内质网应激是细胞对于内源性应激的一种适应性反应,由未折叠蛋白所诱导,其机制被称为未折叠蛋白反应(UPR)。哺乳动物UPR包含3个经典的分支通路,分别以胰腺内质网激酶(PERK)、需肌醇跨膜激酶/核酸内切酶1(IRE1)和活化转录因子6(ATF6)作为近端效应物,能够促进蛋白质折叠和转运,停止蛋白质的翻译合成,降解清除错误蛋白,并可启动凋亡程序诱导不能修复错误蛋白的细胞凋亡,从而维持内环境与组织细胞功能的稳态。支气管上皮内含多种蛋白质合成分泌旺盛的细胞类型,本身易出现内质网应激;支气管哮喘时,气道炎症状态等因素的存在被认为可以诱发UPR,并与气道炎症反应互为因果,交互作用。目前的研究认为,在支气管哮喘发病中,气道上皮细胞的钙稳态失调、透明质酸与黏蛋白的异常分泌、细胞因子对炎细胞的募集作用以及免疫调节状态的异常等环节与内质网应激存在密切的关系。本文即对内质网应激与哮喘的相关研究作一综述。     

胰岛素生长因子与内质网应激关系的研究进展

内质网应激(ERS)是脑缺血/再灌注、病毒性肝炎、乳腺癌等众多疾病发生的重要病理过程,同时是一个多因素、多步骤协同的复杂病理生理过程。近来的研究报道,胰岛素生长因子(IGFs)能通过ERS的多条路径的联系恢复内质网稳态,促进细胞存活,但在内质网持续应激时则启动内质网相关凋亡途径,诱导细胞凋亡。该文以IGFs为切入点,探讨IGFs和ERS的相互关系,并对之进行综述。     

心力衰竭中内质网应激相关诱导因子的研究进展

内质网合成及加工蛋白的功能异常可引起未折叠蛋白的聚集,从而引起内质网应激(ERS)和未折叠蛋白反应。适度的ERS使心肌细胞发生代偿性肥大,但过强和持续的ERS可使心肌细胞由代偿转向凋亡,从而致心力衰竭。该文综述了各种ERS诱导因子在心力衰竭发生、发展中的作用,阐明ERS在心力衰竭病理形成过程中发挥着重要的作用,也为心力衰竭的治疗开启了新思路。     

Role of Endoplasmic Reticulum Stress in Silica-induced Apoptosis in RAW264.7 Cells

Objective We investigated the role of endoplasmic reticulum stress(ERS) in silica-induced apoptosis in alveolar macrophages in vitro. Methods RAW264.7 cells were incubated with 200 μg/mL silica for different time periods. Cell viability was assayed by the MTT assay. Cell apoptosis was evaluated by DAPI staining, flow cytometry analysis, and Western blot analysis of caspase-3. Morphological changes in the endoplasmic reticulum were observed by transmission electron microscopy. The expression of ERS markers binding protein(BiP) and CCAAT-enhancer-binding protein homologous protein(CHOP) was examined by Western blotting and real-time PCR. As an inhibitor of ERS, 4-phenylbutyric acid(4-PBA) was used in the experiments. Results Silica exposure induced nuclear condensation and caspase-3 expression in RAW264.7 cells. The number of apoptotic cells increased after silica exposure in a time-dependent manner. Silica treatment induced expansion of the endoplasmic reticulum. In addition, the expression of BiP and CHOP increased in silica-stimulated cells. Furthermore, 4-PBA treatment inhibited silica-induced endoplasmic reticulum expansion and the expression of Bi P and CHOP. Moreover, 4-PBA treatment attenuated nuclear condensation, reduced apoptotic cells, and downregulated caspase-3 expression in silica-stimulated cells. Conclusion Silica-induced ERS is involved in the apoptosis of alveolar macrophages.     

内质网应激与肾脏纤维化

内质网应激是机体对各种病理生理刺激的一种自身应答机制,适度的内质网应激可以恢复内质网稳态以维持细胞生存;而持久或严重的内质网应激则可能导致细胞程序性死亡或凋亡,造成器官损害.研究已证实内质网应激与多种肾脏疾病如糖尿病肾病、膜性肾病、急性肾小管-间质损害、肾脏衰老、肾间质纤维化等密切相关;本文将主要对内质网应激在肾脏纤维化进展中的作用作一综述.     

Endoplasmic Reticulum Stress Induced by Tunicamycin and Antagonistic Effect of Tiantai No.1(天泰1号) on Mesenchymal Stem Cells

<正>Objective:Changes of the internal and external cellular environments can induce calcium homeostasis disorder and unfolded protein aggregation in the endoplasmic reticulum(ER).This ER function disorder is called endoplasmic reticulum stress(ERS).Severe long-term ERS can trigger the ER apoptosis signaling pathway,resulting in cell apoptosis and organism injury.Recent researches revealed that ERS-induced cell death was involved in the neurocyte retrogradation in the progress of neuron degenerative diseases,such as Alzheimer's disease(AD),Parkinson's disease and so on.Therefore,the protection effect of the traditional Chinese drug——Tiantai No.1(天泰1号) on the ERS injury of AD was investigated at the molecular gene level in this study with a view to explore the gene pharmacodynamic actions and mechanisms of this drug.Methods: Primarily cultured marrow mesenchymal stem cells(MSCs) of rats were treated by tunicamycin(TM) in order to induce ERS.RT-PCR,fluorescence immunocytochemistry and Western blot techniques were used to determine the mRNA and protein expression levels of the protective stress protein-ER molecular chaperones GRP78 and GRP94(which would assist cells to resist cellular stress injury),and to determine the mRNA and protein expression levels of apoptosis promoting molecule Caspase-12 on the membrane of the ER,respectively. Results:Protein expression levels of GRP78 and GRP94 were significantly increased in the TM-induced MSCs, and the mRNA level of Caspase-12 was also remarkably increased in the TM-induced MSCs(P0.05).All these proved that the ERS model was successfully established by TM in MSC.Meanwhile,the mRNA and protein levels of GRP78 and GRP94 were all significantly increased compared with the model group(P0.05 or P0.01) after MSCs were treated with Tiantai No.1 while the mRNA and protein expression levels of Caspase-12 were significantly decreased compared with the model group(P0.05 or P0.01).This effect showed a dose dependent manner.Conclusion:Tiantai No.1 might attenuate the cell apoptosis induced by ERS injury,and thus protect the neurons against AD.     

Endoplasmic reticulum stress-induced apoptosis in the development of reproduction

Proteins synthesized in the endoplasmic reticulum(ER) are properly folded with the assistance of ER chaperones. Accumulation of misfolded protein in the ER triggers an adaptive ER stress(ERS) response termed the unfolded protein response. Recent interest has focused on the possibility that the accumulation of misfolded proteins can also contribute to reproductive response, including preimplantation embryos, testicular germ cell, placenta, and unexplained intrauterine growth restriction(IUGR). The major ERS pathway constituents are present at all stages of preimplantation development and that the activation of ERS pathways can be induced at the 8-cell, morula and blastocyst stage. This review mainly introduced the research progress of ERS induced apoptosis of reproductive cells, providing a new direction for the research of reproductive disease therapy.     

阿托伐他汀对同型半胱氨酸诱导内皮细胞内质网应激的抑制作用

目的： 观察阿托伐他汀对同型半胱氨酸（Hcy）诱导的人脐静脉内皮细胞内质网应激（endoplasmic reticulum stress,ERS）以及凋亡的影响。方法: 不同浓度的Hcy或联合阿托伐他汀处理人脐静脉内皮细胞后,流式细胞术检测细胞凋亡率,实时定量PCR和蛋白质印迹法测定ERS相关分子BiP、CHOP及p-eIF2α、p- PERK的表达变化。结果: Hcy呈浓度依赖性地诱导内皮细胞ERS相关分子BiP、CHOP及p-eIF2α、p-PERK的表达,阿托伐他汀可明显抑制Hcy诱导的内皮细胞ERS相关分子的表达,减少内皮细胞凋亡。结论： 阿托伐他汀可通过下调ERS相关信号通路,抑制Hcy诱导的人脐静脉内皮细胞凋亡。