Cell death-inducing function and activation mechanism of Cl- channel

Cl-通道的细胞死亡诱导功能及激活机制

• 批准号: 14207002
• 负责人: OKADA Yasunobu
• 金额: $ 31.78万
• 依托单位: National Institute for Physiological Sciences (2004)Okazaki National Research Institutes (2002-2003)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14207002/
• 关键词: Cl- channel; apoptosis; necrosis; cell volume regulation; lactacidosis; excitotoxicit; ischemia; cell death; ニューロン; 心筋細胞; グリア

Cell acidosis may induce the necrotic cell volume increase (NVI) due to NaCl accumulation within the cells by stimulation of Na+-H+ antiporter and C1--HC03- antiporter. Acidosis with lactate accumulation due to augmented glycolysis-fermentation reactions is known to be frequently associated with cerebral ischemia or trauma and to result in necrosis of glial and neuronal cells. Under such conditions called lactacidosis, cell swelling is strengthened by entry of lactate and proton via monocarboxylate transporters. In cultured glial C6 cells, persistent swelling was in fact induced by lactacidosis. Furthermore, the succeeding regulatory volume decrease (RVD) was impaired under lactacidosis conditions due to inhibition on volume-sensitive outwardly rectifying (VSOR) Cl- channels. When lactacidosis-resistant anion channels were exogenously introduced by applying an anion channel-forming toxin protein purified from Helicobacter pylori, VacA, glial cells restored the RVD. Furthermore, lactaci … More dosis-induced necrotic cell death was significantly rescued, when lactacidosis-resistant anion channels were exogenously introduced into C6 cells by pretreatment with the VacA protein. Thus, it is concluded that inhibition of volume-regulatory VSOR Cl- channels are involved in the NVI in glial cells.Apoptotic volume decrease (AVD) is a pivotal event triggering a cell to undergo apoptosis and is induced by ionic effluxes resulting mainly from increased K+ and Cl- conductances. In human epithelia HeLa cells both mitochondrion- and death receptor-mediated apoptosis inducers (staurosporine and Fas ligand or TNFα) rapidly activate Cl- currents that show properties phenotypical of VSOR Cl- channel currents. Staurosporine rapidly increased the intracellular level of reactive oxygen species (ROS). A ROS scavenger and an NAD(P)H oxidase inhibitor blocked the current activation by staurosporine. A ROS scavenger also inhibited AVD, caspase-3 activation and apoptotic cell death induced by staurosporine. Thus, it is concluded that an apoptosis-triggering anion conductance is carried by the VSOR Cl- channel and that the channel activation upon apoptotic stimulation with staurosporine is mediated by reactive oxygen species.Cultured mouse cortical neurons express the volume-sensitive outwardly rectifying (VSOR) anion channel. Under excitotoxic conditions, neurons suffered from pathological swelling and dendritic beading, called varicosity, and thereafter necrosis. Both whole-cell and single-channel recordings confirmed that the VSOR channel was activated by excitotoxicity. When a VSOR channel blocker was applied during exctitotoxic stimulation, varicosity formation and necrotic cell death were largely inhibited. Thus, it is concluded that the VSOR channel plays a role in excitotoxicity-induced varicosity formation and necrotic cell death. Less

细胞酸中毒可能通过刺激Na+ -H+抗胞菌和C1-HC03-抗毒剂引起的NaCl积累而引起坏死细胞体积的增加（NVI）。已知由于增强糖酵解 - 发酵反应而导致的乳酸酸中毒经常与脑缺血或创伤有关，并导致神经胶质和神经元细胞坏死。在这种称为乳酸性病的条件下，通过单羧酸盐转运蛋白进入乳酸和质子来加强细胞吞咽。在培养的神经胶质C6细胞中，实际上是由乳酸病诱导的持续吞咽。此外，由于抑制对体积敏感的外部整流（VSOR）CL-通道，在乳酸病条件下，连续的调节体积减小（RVD）受损。当通过施加从幽门螺杆菌幽门螺杆菌纯化的阴离子通道形成的毒素蛋白来恢复RVD时，抗乳酸性阴离子通道被外源引入。此外，当抗乳糖酸的阴离子通道通过用VACA蛋白预处理到C6细胞中时，乳酸…更多的Dosis诱导的坏死细胞死亡得到了显着恢复。得出的结论是，抑制体积调节性VSOR CL-通道与神经胶质细胞中的NVI有关。凋亡体积降低（AVD）是一个关键事件，触发细胞导致细胞凋亡，并主要由增加K+和Cl-Cont-contimants引起的离子外排。在人类上皮细胞中，线粒体和死亡受体介导的凋亡诱导剂（星形孢菌素和FAS配体或TNFα）都迅速激活Cl contrents，这些cl频率显示出VSOR CL-通道电流表的特性表型。星形孢子迅速增加了活性氧（ROS）的细胞内水平。 ROS清除剂和NAD（P）H氧化物抑制剂阻止了星形孢菌素的电流激活。 ROS的清道夫还抑制了星形孢菌素诱导的AVD，caspase-3激活和凋亡细胞死亡。这就是结论，VSOR CL-通道携带了凋亡触发阴离子的电导，并且用星形孢菌碱介导凋亡刺激时的通道激活是由活性氧培养的小鼠皮层神经元培养的。在兴奋性毒性条件下，神经元患有病理吞咽和树突状珠子，称为静脉曲张，此后坏死。全细胞和单渠道记录都证实了VSOR通道是通过兴奋性毒性激活的。当在兴奋性毒性刺激期间应用VSOR通道阻滞剂时，静脉曲张的形成和坏死细胞死亡在很大程度上被抑制。这就是结论，VSOR通道在兴奋性毒性引起的静脉曲张形成和坏死细胞死亡中起作用。较少的

项目成果

Impaired activity of volume-sensitive anion channel during lactacidosis-induced swelling in neuronally differentiated NG108-15 cells.

在乳酸中毒引起的神经分化 NG108-15 细胞肿胀过程中，体积敏感阴离子通道的活性受损。

• 发表时间: 2002
• 期刊: Brain Res. 957
• 作者: Akiyama K;Ebihara S;Yada;A.;Matsumura;K.;Aiba;S.;Nukiwa;T.;Takai;T.;S.Mori
• 通讯作者: S.Mori

ClC-3-independent sensitivity of apoptosis to Cl^- channel blockers in mouse cardiomyocytes.

小鼠心肌细胞中细胞凋亡对 Cl^- 通道阻滞剂的 ClC-3 独立敏感性。

• 发表时间: 2005
• 期刊: Cell.Physiol.Biochem. 15
• 作者: E.L. Lee;T. Shimizu;T. Ise;T. Numata;K. Kohno & Y. Okada;Frank Wehner;Hai-Yan Wang;Takahiro Shimizu;H.Inoue;H.Inoue;E.L.Lee;E.Maeno;M.Nukui;E.Maeno;T.Ise;X.Wang;H.Inoue;N.Takahashi
• 通讯作者: N.Takahashi

I.F.Abdullaev, R.Z.Sabirov, Y.Okada: "Upregulation of swelling-activated Cl^- channel sensitivity to cell volume by activation of EGF receptors in murine mammary cells."J.Physiol.(London). 549. 749-758 (2003)

I.F.Abdullaev、R.Z.Sabirov、Y.Okada：“通过激活小鼠乳腺细胞中的 EGF 受体，上调肿胀激活的 Cl^- 通道对细胞体积的敏感性。”J.Physiol.（伦敦）。

Role of ATP-conductive anion channel in ATP release from neonatal rat cardiomyocytes in ischemic or hypoxic conditions.

ATP 传导阴离子通道在缺血或缺氧条件下新生大鼠心肌细胞 ATP 释放中的作用。

• 发表时间: 2004
• 期刊: J.Physiol.(London) 559
• 作者: Lee E-J.;Iai H.;Koizumi N.;Sano H.;Kanzaki-Kato N. et al.;Harada M. et al.;Kameda T. et al.;Yan M.Y.et al.;Ise N.et al.;Nakayama K. et al.;A.K.Dutta
• 通讯作者: A.K.Dutta

Nabekura T, Morishima S, Cover TL, Mori S, Kannan H, Komune S, Okada Y: "Recovery from lactacidosis-induced glial cell swelling with the aid of exogenous anion channels"Glia. 41. 247-259 (2003)

Nabekura T、Morishima S、Cover TL、Mori S、Kannan H、Komune S、Okada Y：“借助外源性阴离子通道从乳酸中毒引起的神经胶质细胞肿胀中恢复”神经胶质细胞。