Xiamen Cardiovascular Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.
Cord Blood Bank, Institute of Eugenics and Perinatology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China.
Stem Cell Rev Rep. 2023 Oct;19(7):2481-2496. doi: 10.1007/s12015-023-10591-5. Epub 2023 Aug 3.
Protection of cardiac function following myocardial infarction was largely enhanced by bradykinin-pretreated cardiac-specific c-kit (BK-c-kit) cells, even without significant engraftment, indicating that paracrine actions of BK-c-kit cells play a pivotal role in angiogenesis. Nevertheless, the active components of the paracrine actions of BK-c-kit cells and the underlying mechanisms remain unknown. This study aimed to define the active components of exosomes from BK-c-kit cells and elucidate their underlying protective mechanisms.
Matrigel tube formation assay, cell cycle, and mobility in human umbilical vein endothelial cells (HUVECs) and hindlimb ischemia (HLI) in mice were applied to determine the angiogenic effect of condition medium (CM) and exosomes. Proteome profiler, microRNA sponge, Due-luciferase assay, microRNA-sequencing, qRT-PCR, and Western blot were used to determine the underlying mechanism of the angiogenic effect of exosomes from BK-c-kit.
As a result, BK-c-kit CM and exosomes promoted tube formation in HUVECs and the repair of HLI in mice. Angiogenesis-related proteomic profiling and microRNA sequencing revealed highly enriched miR-3059-5p as a key angiogenic component of BK-c-kit exosomes. Meanwhile, loss- and gain-of-function experiments revealed that the promotion of angiogenesis by miR-3059-5p was mainly through suppression of TNFSF15-inhibited effects on vascular tube formation, cell proliferation and cell migration. Moreover, enhanced angiogenesis of miR-3059-5p-inhibited TNFSF15 has been associated with Akt/Erk1/2/Smad2/3-modulated signaling pathway.
Our results demonstrated a novel finding that BK-c-kit cells enrich exosomal miR-3059-5p to suppress TNFSF15 and promote angiogenesis against hindlimb ischemia in mice.
心肌梗死后，通过预先用缓激肽预处理的心脏特异性 c-kit（BK-c-kit）细胞，极大地增强了心脏功能的保护作用，即使没有明显的植入，这表明 BK-c-kit 细胞的旁分泌作用在血管生成中起着关键作用。然而，BK-c-kit 细胞旁分泌作用的活性成分及其潜在机制仍不清楚。本研究旨在确定 BK-c-kit 细胞来源的外泌体的活性成分，并阐明其潜在的保护机制。
用人脐静脉内皮细胞（HUVEC）的基质胶管形成实验、细胞周期和迁移实验以及小鼠后肢缺血（HLI）实验来确定条件培养基（CM）和外泌体的血管生成作用。蛋白质组谱分析、microRNA 海绵、Due-luciferase 测定、microRNA 测序、qRT-PCR 和 Western blot 用于确定 BK-c-kit 细胞来源的外泌体的血管生成作用的潜在机制。
结果表明，BK-c-kit CM 和外泌体促进了 HUVEC 中的管形成和小鼠的 HLI 修复。血管生成相关的蛋白质组学分析和 microRNA 测序显示，miR-3059-5p 作为 BK-c-kit 外泌体的关键血管生成成分高度富集。同时，失活和功能获得实验表明，miR-3059-5p 促进血管生成主要是通过抑制 TNFSF15 对血管管形成、细胞增殖和细胞迁移的抑制作用。此外，miR-3059-5p 抑制 TNFSF15 的增强血管生成与 Akt/Erk1/2/Smad2/3 调节的信号通路有关。
我们的研究结果表明，BK-c-kit 细胞通过富集外泌体 miR-3059-5p 来抑制 TNFSF15，从而促进了对小鼠后肢缺血的血管生成，这是一个新的发现。
