背景:2019年冠状病毒病(COVID-19)引起的急性心脏损伤会增加死亡率。由COVID-19引起的急性心脏损伤需要了解严重的急性呼吸综合征冠状病毒2(SARS-CoV-2)如何直接感染心肌细胞。这项研究通过在转录组水平上使用SARS-CoV-2感染人类诱导多能干细胞来源的心肌细胞(hiPSC-CM)的模型,为相关研究提供了坚实的基础,强调本研究与相关研究的相关性。先前已通过生物信息学研究了hiPSC-CM中的SARS-CoV-2感染,而没有提出完整的分子生物学过程。我们为hiPSC-CM中SARS-CoV-2感染的完整分子生物学过程提供了独特的生物信息学观点。
方法:为了验证RNA-seq数据集,我们使用GSE184715和GSE150392进行分析研究,GSE193722用于细胞水平的验证,和GSE169241用于心脏组织样本的验证。使用GeneCards和MsigDB数据库来寻找与表型相关的基因。除了差异表达分析和主成分分析(PCA),我们还进行了蛋白质-蛋白质相互作用(PPI)分析,功能富集分析,集线器基因分析,上游转录因子预测,和药物预测。
结果:差异表达基因(DEGs)分为四类:心肌细胞细胞骨架蛋白抑制,原癌基因激活和炎症,线粒体功能障碍,胞浆生理功能。每个枢纽基因都显示出良好的诊断预测,这在其他数据集中得到了很好的验证。抑制的生物学功能包括心肌细胞细胞骨架蛋白,三磷酸腺苷(ATP)合成和电子传递链(ETC),葡萄糖代谢,氨基酸代谢,脂肪酸代谢,丙酮酸代谢,柠檬酸循环,核酸代谢,复制,转录,翻译,泛素化,自噬,和细胞运输。原癌基因,炎症,核因子-κB(NF-κB)途径,干扰素信号被激活,以及炎症因子。病毒感染激活多种途径,包括干扰素途径,原癌基因和线粒体氧化应激,同时抑制心肌细胞骨架蛋白和能量代谢。感染限制了细胞内的合成和代谢,以及线粒体能量合成的原料。线粒体功能障碍和能量异常最终是由原癌基因激活和SARS-CoV-2感染引起的。干扰素途径的激活,原癌基因上调,和线粒体氧化应激引起炎症反应并导致心肌细胞收缩减弱。复制,转录,翻译,泛素化,自噬,细胞运输是生理上下降的功能之一。
结论:SARS-CoV-2在hiPSC-CM中的感染基本上是通过线粒体功能障碍介导的。针对线粒体功能障碍的治疗性干预措施可以缓解与SARS-CoV-2感染相关的心血管并发症。
BACKGROUND: Acute cardiac injury caused by coronavirus disease 2019 (COVID-19) increases mortality. Acute cardiac injury caused by COVID-19 requires understanding how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) directly infects cardiomyocytes. This study provides a solid foundation for related studies by using a model of SARS-CoV-2 infection in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) at the transcriptome level, highlighting the relevance of this study to related studies. SARS-CoV-2 infection in hiPSC-CMs has previously been studied by bioinformatics without presenting the full molecular biological process. We present a unique bioinformatics view of the complete molecular biological process of SARS-CoV-2 infection in hiPSC-CMs.
METHODS: To validate the RNA-seq datasets, we used GSE184715 and GSE150392 for the analytical studies, GSE193722 for validation at the cellular level, and GSE169241 for validation in heart tissue samples. GeneCards and MsigDB databases were used to find genes associated with the phenotype. In addition to differential expression analysis and principal component analysis (PCA), we also performed protein-protein interaction (PPI) analysis, functional enrichment analysis, hub gene analysis, upstream transcription factor prediction, and drug prediction.
RESULTS: Differentially expressed genes (DEGs) were classified into four categories: cardiomyocyte cytoskeletal protein inhibition, proto-oncogene activation and inflammation, mitochondrial dysfunction, and intracellular cytoplasmic physiological function. Each of the hub genes showed good diagnostic prediction, which was well validated in other datasets. Inhibited biological functions included cardiomyocyte cytoskeletal proteins, adenosine triphosphate (ATP) synthesis and electron transport chain (ETC), glucose metabolism, amino acid metabolism, fatty acid metabolism, pyruvate metabolism, citric acid cycle, nucleic acid metabolism, replication, transcription, translation, ubiquitination, autophagy, and cellular transport. Proto-oncogenes, inflammation, nuclear factor-kappaB (NF-κB) pathways, and interferon signaling were activated, as well as inflammatory factors. Viral infection activates multiple pathways, including the interferon pathway, proto-oncogenes and mitochondrial oxidative stress, while inhibiting cardiomyocyte backbone proteins and energy metabolism. Infection limits intracellular synthesis and metabolism, as well as the raw materials for mitochondrial energy synthesis. Mitochondrial dysfunction and energy abnormalities are ultimately caused by proto-oncogene activation and SARS-CoV-2 infection. Activation of the interferon pathway, proto-oncogene up-regulation, and mitochondrial oxidative stress cause the inflammatory response and lead to diminished cardiomyocyte contraction. Replication, transcription, translation, ubiquitination, autophagy, and cellular transport are among the functions that decline physiologically.
CONCLUSIONS: SARS-CoV-2 infection in hiPSC-CMs is fundamentally mediated via mitochondrial dysfunction. Therapeutic interventions targeting mitochondrial dysfunction may alleviate the cardiovascular complications associated with SARS-CoV-2 infection.