Grade 2016 Class 2, The First School of Clinical Medicine, Nanjing Medical University, Nanjing, 211166, China.
Department of Cardiology, Qingdao Municipal Hospital, Nanjing Medical University, Qingdao, 266011, China.
Mol Cell Biochem. 2020 Oct;473(1-2):101-110. doi: 10.1007/s11010-020-03811-w. Epub 2020 Jun 29.
Endothelial-to-mesenchymal transition (EndMT) has been reported as a key factor in myocardial fibrosis. Acetylcholine (ACh), a neurotransmitter of the vagus nerve, has been confirmed to exert cardio-protective properties with unclear mechanisms. In this study, the specific markers of cell injury, EndMT, inflammation, and autophagy were measured. We found that treatment with ACh prevented hypoxia-induced cell viability reduction and apoptosis in human cardiac microvascular endothelial cells (HCMECs). Additionally, our results indicate that pre-treatment with ACh significantly suppresses hypoxia-induced EndMT and NF-κB activation in HCMECs. ACh also reduced hypoxia-inducible factor (HIF)-1ɑ protein levels under hypoxia. Knock down of HIF-1ɑ enhanced the inhibitory effect of ACh on NF-κB activation. The NF-κB-specific small molecule inhibitor BAY 11-7082, prostaglandin E2, and LY294002 prevented hypoxia-induced EndMT. Moreover, our data show that hypoxia triggers autophagy in HCMECs, and ACh significantly upregulates autophagy activity. Pre-treatment of HCMECs with 3-methyladenine or chloroquine partially reversed ACh-induced EndMT inhibition. These results suggest that ACh may confer protection against hypoxia-induced EndMT through the inhibition of NF-κB and the induction of autophagy.
内皮到间质转化（EndMT）已被报道为心肌纤维化的关键因素。迷走神经的神经递质乙酰胆碱（ACh）已被证实具有心脏保护作用，但具体机制尚不清楚。在本研究中，测量了细胞损伤、EndMT、炎症和自噬的特定标志物。我们发现，ACh 处理可预防缺氧诱导的人心肌微血管内皮细胞（HCMECs）活力降低和细胞凋亡。此外，我们的结果表明，ACh 预处理可显著抑制 HCMECs 中缺氧诱导的 EndMT 和 NF-κB 激活。ACh 还可降低缺氧诱导因子（HIF）-1ɑ蛋白水平。HIF-1ɑ 的敲低增强了 ACh 对 NF-κB 激活的抑制作用。NF-κB 特异性小分子抑制剂 BAY 11-7082、前列腺素 E2 和 LY294002 可预防缺氧诱导的 EndMT。此外，我们的数据表明，缺氧可在 HCMECs 中引发自噬，ACh 可显著上调自噬活性。HCMECs 先用 3-甲基腺嘌呤或氯喹预处理可部分逆转 ACh 诱导的 EndMT 抑制。这些结果表明，ACh 可能通过抑制 NF-κB 和诱导自噬来对抗缺氧诱导的 EndMT。
