Aims Circular RNAs (circRNAs) are considered important regulators of biological processes, but their impact on atherosclerosis development, a key factor in coronary artery disease (CAD), has not been fully elucidated. We aimed to investigate their potential use in patients with CAD and the pathogenesis of atherosclerosis. Methods and results Patients with stable angina (SA) or acute coronary syndrome (ACS) and controls were selected for transcriptomic screening and quantification of circRNAs in blood cells. We stained carotid plaque samples for circRNAs and performed gain- and loss-of-function studies in vitro. Western blots, protein interaction analysis, and molecular approaches were used to perform the mechanistic study. ApoE−/− mouse models were employed in functional studies with adeno-associated virus-mediated genetic intervention. We demonstrated elevated circARCN1 expression in peripheral blood mononuclear cells from patients with SA or ACS, especially in those with ACS. Furthermore, higher circARCN1 levels were associated with a higher risk of developing SA and ACS. We also observed elevated expression of circARCN1 in carotid artery plaques. Further analysis indicated that circARCN1 was mainly expressed in monocytes and macrophages, which was also confirmed in atherosclerotic plaques. Our in vitro studies provided evidence that circARCN1 affected the interaction between HuR and ubiquitin-specific peptidase 31 (USP31) mRNA, resulting in attenuated USP31-mediated NF-κB activation. Interestingly, macrophage accumulation and inflammation in atherosclerotic plaques were markedly decreased when circARCN1 was knocked down with adeno-associated virus in macrophages of ApoE−/− mice, while circARCN1 overexpression in the model exacerbated atherosclerotic lesions. Conclusions Our findings provide solid evidence macrophagic-expressed circARCN1 plays a role in atherosclerosis development by regulating HuR-mediated USP31 mRNA stability and NF-κB activation, suggesting that circARCN1 may serve as a factor for atherosclerotic lesion formation.

中文翻译：

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CircARCN1 通过调节巨噬细胞中 HuR 介导的 USP31 mRNA 加重动脉粥样硬化


目的 环状 RNA （circRNAs） 被认为是生物过程的重要调节因子，但它们对动脉粥样硬化发展的影响是冠状动脉疾病 （CAD） 的一个关键因素，尚未完全阐明。我们旨在研究它们在 CAD 患者中的潜在用途和动脉粥样硬化的发病机制。方法和结果 选择稳定型心绞痛 （SA） 或急性冠脉综合征 （ACS） 患者和对照进行血细胞中 circRNAs 的转录组学筛选和定量。我们对颈动脉斑块样品进行 circRNAs 染色，并在体外进行了功能增益和丧失研究。使用蛋白质印迹、蛋白质相互作用分析和分子方法进行机制研究。ApoE - / - 小鼠模型用于腺相关病毒介导的遗传干预的功能研究。我们证明 SA 或 ACS 患者外周血单核细胞中 circARCN1 表达升高，尤其是在 ACS 患者中。此外，较高的 circARCN1 水平与较高的 SA 和 ACS 风险相关。我们还观察到颈动脉斑块中 circARCN1 的表达升高。进一步分析表明，circARCN1 主要在单核细胞和巨噬细胞中表达，在动脉粥样硬化斑块中也得到证实。我们的体外研究提供了证据表明，circARCN1 影响 HuR 与泛素特异性肽酶 31 （USP31） mRNA 之间的相互作用，导致 USP31 介导的 NF-κB 激活减弱。有趣的是，当 ApoE - / - 小鼠巨噬细胞中的腺相关病毒敲低 circARCN1 时，动脉粥样硬化斑块中的巨噬细胞积累和炎症显着减少，而模型中 circARCN1 的过表达加剧了动脉粥样硬化病变。 结论 我们的研究结果提供了确凿的证据，巨噬细胞表达的 circARCN1 通过调节 HuR 介导的 USP31 mRNA 稳定性和 NF-κB 激活在动脉粥样硬化发展中发挥作用，表明 circARCN1 可能是动脉粥样硬化病变形成的一个因素。