Involvement of endoplasmic reticulum stress response and IRE1-mediated ASK1/JNK/Mcl-1 pathways in silver nanoparticle-induced apoptosis of human retinal pigment epithelial cells
Involvement of endoplasmic reticulum stress response and IRE1-mediated ASK1/JNK/Mcl-1 pathways in silver nanoparticle-induced apoptosis of human retinal pigment epithelial cells
复制标题
DOI：
10.1016/j.tox.2020.152540
复制
发表时间：
2020-09-01
期刊：
影响因子：
4.5
通讯作者：
Lee, Young-Ha
中科院分区：
文献类型：
--
作者：
Quan, Juan-Hua;Gao, Fei Fei;Lee, Young-Ha
银纳米颗粒（AgNPs）对多种人类细胞类型具有细胞毒性作用。内质网（ER）对细胞毒性损伤非常敏感。视网膜组织容易受到内外刺激的影响。然而，AgNPs对人视网膜细胞的影响尚不清楚。本研究探讨了AgNPs对人视网膜色素上皮（RPE） ARPE-19细胞内质网应激诱导的影响及其作用机制。我们发现AgNPs显著增加ARPE-19细胞的细胞毒性，并以剂量依赖性的方式刺激ARPE-19细胞中的caspase-3和聚（adp -核糖）聚合酶（PARP）裂解，以及线粒体膜电位（MMP）去极化（0.2-5 μ g/mL，持续18 h）。AgNPs （5 μ g/mL，作用18 h）诱导多个内质网应激标记物的表达上调，包括CCAAT/增强子结合蛋白同源蛋白（CHOP）、磷酸化蛋白激酶rna样内质网激酶（PERK）、真核起始因子2 α (eIF2 α)、肌醇需要蛋白1 （IRE1）和裂解激活转录因子6 （ATF6）的表达上调。AgNPs还激活了ARPE-19细胞中的ASK1和JNK，诱导Bax和Puma表达增加，Mcl-1表达降低。然而，4-PBA预处理对内质网应激反应的抑制包括agnp处理的ARPE-19细胞中p-PERK、p-IRE1、CHOP、cleaved ATF6、p-ASK1、p-JNK、cleaved caspase-3、procaspase-12和MMP去极化水平的明显和剂量依赖性降低；它还导致ARPE-19细胞中Mcl-1蛋白水平以剂量依赖的方式显著增加。在agnps处理的ARPE-19细胞中，JNK抑制剂SP600125预处理显著减弱caspase-3切割和MMP去极化，并以剂量依赖的方式增加Mcl-1蛋白水平。因此，我们的研究表明，AgNPs通过内质网应激反应和内质网应激依赖性线粒体凋亡，通过IRE1/ASK1/JNK/Mcl-1途径诱导人RPE ARPE-19细胞凋亡。
Silver nanoparticles (AgNPs) have cytotoxic effects on various human cell types. The endoplasmic reticulum (ER) is very sensitive to cytotoxic damage. Retina tissue is easily affected by internal and external stimuli. However, the effect of AgNPs on human retinal cells is not known. This study examined the effect of AgNPs on ER stress induction and their mechanism of action in human retinal pigment epithelium (RPE) ARPE-19 cells. We found that AgNPs significantly increased ARPE-19 cell cytotoxicity and stimulated caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage, as well as mitochondrial membrane potential (MMP) depolarization, in ARPE-19 cells in a dose-dependent manner (0.2-5 mu g/mL for 18 h). AgNPs (5 mu g/mL for 18 h) induced several signature ER stress markers, as indicated by the upregulated expressions of CCAAT/enhancer-binding protein-homologous protein (CHOP), phosphorylated protein kinase RNA-like ER kinase (PERK), eukaryotic initiation factor 2 alpha (eIF2 alpha), and inositol-requiring protein 1 (IRE1), and cleaved activating transcription factor 6 (ATF6). AgNPs also activated ASK1 and JNK in ARPE-19 cells, and induced increases in Bax and Puma expressions, as well as a decrease in Mcl-1 expression. However, inhibition of the ER stress response by pretreatment with 4-PBA included apparently and dose-dependently reduced levels of p-PERK, p-IRE1, CHOP, cleaved ATF6, p-ASK1, p-JNK, cleaved caspase-3, procaspase-12, and MMP depolarization in AgNP-treated ARPE-19 cells; it also led to significantly increased Mcl-1 protein levels in a dose-dependent manner in ARPE-19 cells. Pretreatment with JNK inhibitor SP600125 significantly attenuated caspase-3 cleavage and MMP depolarization and increased Mcl-1 protein levels in AgNPs-treated ARPE-19 cells in a dose-dependent manner. Hence, our study demonstrated that AgNPs induced apoptosis in human RPE ARPE-19 cells by ER stress response and ER stress-dependent mitochondrial apoptosis via the IRE1/ASK1/JNK/Mcl-1 pathways.