Tongxinluo Reverses the Hypoxia-suppressed Claudin-9 in Cardiac Microvascular Endothelial Cells.
Tongxinluo Reverses the Hypoxia-suppressed Claudin-9 in Cardiac Microvascular Endothelial Cells.
复制标题
通心络逆转心脏微血管内皮细胞缺氧抑制的Claudin-9
DOI：
10.4103/0366-6999.176076
复制
发表时间：
2016-02-20
影响因子：
6.1
通讯作者：
Wang Y
中科院分区：
文献类型：
--
作者：
Liu K;Wang XJ;Li YN;Li B;Qi JS;Zhang J;Wang Y
Claudin-5、claudin-9、claudin-11在内皮细胞中表达，构成紧密连接，缺乏Claudin-5、claudin-9、claudin-11可导致高通透性，这是心血管疾病的启动过程和病理基础。虽然通心络（TXL）具有令人满意的抗心绞痛作用，但其是否以及如何调节缺氧刺激的人心脏微血管内皮细胞（HCMECs）中的claudin-5、claudin-9和claudin-11尚未见报道。在本研究中，用CoCl2刺激HCMECs模拟缺氧，并用TXL治疗。首先，确定了claudin-5、claudin-9、claudin-11的信使RNA （mRNA）表达。然后观察TXL处理后claudin-9的蛋白含量、分布及细胞形态变化。此外，我们还检测了claudin-9基因启动子中保证转录激活的组蛋白H3K9乙酰化（H3K9ac）的分布和含量，探讨了TXL在缺氧刺激的HCMECs中上调claudin-9的潜在机制。我们发现缺氧抑制claudin-9基因在HCMECs中的表达（F = 7.244, P = 0.011），而TXL可以逆转缺氧抑制claudin-9基因的表达（F = 61.911, P = 0.000），这可以通过其蛋白含量的变化（F = 29.142, P = 0.000）得到验证。此外，高剂量TXL可促进缺氧刺激hcmes中claudin-9的细胞膜定位，减轻细胞损伤。此外，高剂量TXL升高了claudin-9基因启动子中缺氧抑制的H3K9ac (F = 37.766; P = 0.000)，激活了claudin-9的转录。结果表明，TXL通过提高其基因启动子中的H3K9ac来逆转缺氧抑制的cladin -9，在HCMECs中发挥保护作用。
Claudin-5, claudin-9, and claudin-11 are expressed in endothelial cells to constitute tight junctions, and their deficiency may lead to hyperpermeability, which is the initiating process and pathological basis of cardiovascular disease. Although tongxinluo (TXL) has satisfactory antianginal effects, whether and how it modulates claudin-5, claudin-9, and claudin-11 in hypoxia-stimulated human cardiac microvascular endothelial cells (HCMECs) have not been reported. In this study, HCMECs were stimulated with CoCl2 to mimic hypoxia and treated with TXL. First, the messenger RNA (mRNA) expression of claudin-5, claudin-9, and claudin-11 was confirmed. Then, the protein content and distribution of claudin-9, as well as cell morphological changes were evaluated after TXL treatment. Furthermore, the distribution and content histone H3K9 acetylation (H3K9ac) in the claudin-9 gene promoter, which guarantees transcriptional activation, were examined to explore the underlying mechanism, by which TXL up-regulates claudin-9 in hypoxia-stimulated HCMECs. We found that hypoxia-suppressed claudin-9 gene expression in HCMECs (F = 7.244; P = 0.011) and the hypoxia-suppressed claudin-9 could be reversed by TXL (F = 61.911; P = 0.000), which was verified by its protein content changes (F = 29.142; P = 0.000). Moreover, high-dose TXL promoted the cytomembrane localization of claudin-9 in hypoxia-stimulated HCMECs, with attenuation of cell injury. Furthermore, high-dose TXL elevated the hypoxia-inhibited H3K9ac in the claudin-9 gene promoter (F = 37.766; P = 0.000), activating claudin-9 transcription. The results manifested that TXL reversed the hypoxia-suppressed claudin-9 by elevating H3K9ac in its gene promoter, playing protective roles in HCMECs.