OBJECTIVE: This study aimed to confirm whether the cardiotoxicity of lenvatinib is associated with endoplasmic reticulum stress by targeting the activating transcription factor 6 (ATF6), inositol- requiring enzyme 1α (IRE1α) and protein kinase RNA-like ER kinase (PERK) signaling pathways.
METHODS: Male C57/BL6 mice were intragastric administration with 30 mg/kg/day lenvatinib. Electrocardiography (ECG) and echocardiography were used to detect arrhythmias and cardiac function. Neonatal rat cardiomyocytes were treated with lenvatinib for 48h. Cell counting kit (CCK8), 2´,7´-dichlorodihydrofluoresceine diacetate (H2DCFHDA), Hoechst 33258 and dihydrorhodamine 123 were respectively used for evaluating cell viability, the level of reactive oxygen species (ROS), nuclear morphological changes and mitochondrial membrane potential (MMP) level.
RESULTS: Lenvatinib remarkably decreased the posterior wall thickness of left ventricle during diastole and systole but caused little decrease to the left ventricular ejection fraction (LVEF, %). Furthermore, lenvatinib greatly prolonged the corrected QT interval (QTc) and altered the morphology of cardiomyocytes. No dramatic difference in fibrosis was found in mouse cardiac slices. Lenvatinib upregulates apoptosis-related protein expression. In addition, lenvatinib increased ERS-related protein expression (GRP78, CHOP, and ATF6) and enhanced PERK phosphorylation. In neonatal rat cardiac myocytes, lenvatinib markedly decreased the viability of cardiomyocytes and induced apoptosis. Furthermore, ROS production increased and MMP decreased. Similar to the mice experiment, lenvatinib caused upregulation of apoptosis-related and ERS-related proteins and increased the phosphorylation levels of PERK and IRE1α.
CONCLUSIONS: Lenvatinib-induced cardiotoxicity is associated with ERS-induced apoptosis by targeting the ATF6, IRE1α, and PERK signaling pathways.
目的:本研究旨在通过靶向激活转录因子6(ATF6)来确认来伐替尼的心脏毒性是否与内质网应激有关,需要肌醇酶1α(IRE1α)和蛋白激酶RNA样ER激酶(PERK)信号通路。
方法:雄性C57/BL6小鼠灌胃给予30mg/kg/天的乐伐替尼。心电图(ECG)和超声心动图用于检测心律失常和心功能。新生大鼠心肌细胞用乐伐替尼处理48h。细胞计数试剂盒(CCK8),2',7'-二氯二氢荧光素二乙酸酯(H2DCFHDA),Hoechst33258和二氢罗丹明123分别用于评估细胞活力,活性氧(ROS)的水平,核形态改变和线粒体膜电位(MMP)水平。
结果:Lenvatinib在舒张期和收缩期显着降低了左心室的后壁厚度,但对左心室射血分数(LVEF,%).此外,lenvatinib大大延长了校正的QT间期(QTc)并改变了心肌细胞的形态。在小鼠心脏切片中没有发现纤维化的显著差异。Lenvatinib上调凋亡相关蛋白表达。此外,乐伐替尼增加了ERS相关蛋白的表达(GRP78,CHOP,和ATF6)和增强的PERK磷酸化。在新生大鼠心肌细胞中,乐伐替尼显著降低心肌细胞活力并诱导细胞凋亡。此外,ROS产量增加,MMP减少。类似于老鼠的实验,lenvatinib导致凋亡相关蛋白和ERS相关蛋白上调,并增加PERK和IRE1α的磷酸化水平。
结论:Lenvatinib诱导的心脏毒性与ERS通过靶向ATF6,IRE1α诱导的细胞凋亡有关,和PERK信号通路。