Extracellular matrix-derived extracellular vesicles promote cardiomyocyte growth and electrical activity in engineered cardiac atria
Extracellular matrix-derived extracellular vesicles promote cardiomyocyte growth and electrical activity in engineered cardiac atria
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DOI：
10.1016/j.biomaterials.2017.09.001
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发表时间：
2017-11-01
期刊：
影响因子：
14
通讯作者：
Kim, Minsuk
中科院分区：
文献类型：
--
作者：
An, Minae;Kwon, Kihwan;Kim, Minsuk
细胞外基质（ECM）在为心脏组织的正常再生提供必要的微环境方面发挥着至关重要的作用。然而，导致 ECM 介导的心脏再生的具体机制尚不清楚。为了阐明潜在的机制，我们使用电子显微镜研究了心脏 ECM 的超微结构。有趣的是，我们观察到来自脱细胞右心房的大量微泡。 RNA 和蛋白质分析表明，它们含有外泌体蛋白质和 microRNA (miRNA)，我们在本文中将其称为 ECM 衍生的细胞外囊泡 (ECM-EV)。 ECM-EV 中的一种特殊 miRNA miR-199a-3p 通过抑制同源结构域蛋白 (HOPX) 表达和增加 GATA 结合 4 (Gata4) 乙酰化来促进分离的新生儿心肌细胞和窦房结细胞的细胞生长。为了确定其机制，我们敲低了 Gata4，并表明 miR-199a-3p 的作用需要 Gata4 才能在分离的新生儿心肌细胞和窦房结细胞中进行细胞增殖。为了进一步探索这种 miRNA 的作用，我们分离了新生儿心肌细胞并将其重新细胞化为心房 ECM，这里称为工程化心房。值得注意的是，miR-199a-3p介导了心肌细胞和窦房结细胞群的富集，并增强了工程化心房中窦房结细胞的心电图信号活性。重要的是，针对 miR-199a-3p 的 miRNA (antagomir) 反义能够消除 miR-199a-3p 在工程化心房中的这些作用。我们进一步在注入 Ang II 的窦房结功能障碍动物模型中发现，经 miR-199-3p 处理的心肌细胞显着改善并恢复了电活动，如心电图正常化所示，而未处理的细胞则没有显示出电恢复。总之，这些结果提供了 ECM 关键作用的明确证据，不仅为心脏组织生长提供支架，而且还通过 ECM 衍生的 miR-199a-3p 促进心房电功能。 (C) 2017 Elsevier Ltd. 保留所有权利。
Extracellular matrix (ECM) plays a critical role in the provision of the necessary microenvironment for the proper regeneration of the cardiac tissue. However, specific mechanisms that lead to ECM-mediated cardiac regeneration are not well understood. To elucidate the potential mechanisms, we investigated ultra-structures of the cardiac ECM using electron microscopy. Intriguingly, we observed large quantities of micro-vesicles from decellularized right atria. RNA and protein analyses revealed that these contained exosomal proteins and microRNAs (miRNAs), which we referred to herein as ECM-derived extracellular vesicles (ECM-EVs). One particular miRNA from ECM-EVs, miR-199a-3p, promoted cell growth of isolated neonatal cardiomyocytes and sinus nodal cells by repressing homeodomain-only protein (HOPX) expression and increasing GATA-binding 4 (Gata4) acetylation. To determine the mechanisms, we knocked down Gata4 and showed that miR-199a-3p actions required Gata4 for cell proliferation in isolated neonatal cardiomyocytes and sinus nodal cells. To further explore the role of this miRNA, we isolated neonatal cardiac cells and recellularized into atrial ECM, referred here has engineered atria. Remarkably, miR-199a-3p mediated the enrichment of cardiomyocyte and sinus nodal cell population, and enhanced electrocardiographic signal activity of sinus nodal cells in the engineered atria. Importantly, antisense of miRNA (antagomir) against miR-199a-3p was capable of abolishing these actions of miR-199a-3p in the engineered atria. We further showed in Ang II-infused animal model of sinus nodal dysfunction that miR-199-3p-treated cardiac cells remarkably ameliorated and restored the electrical activity as shown by normalization of the ECG, in contrast to untreated cells, which did not show electrical recovery. In conclusion, these results provide clear evidence of the critical role of ECM, in not only providing a scaffold for cardiac tissue growth, but also in promoting atrial electrical function through ECM-derived miR-199a-3p. (C) 2017 Elsevier Ltd. All rights reserved.