Protective effects of acetylcholine on hypoxia-induced endothelial-to-mesenchymal transition in human cardiac microvascular endothelial cells

• Published in: Molecular and cellular biochemistry Vol. 473; no. 1-2; pp. 101 - 110
• Main Authors: Li, Zhiyang, Li, Xuelian, Zhu, Yeqian, Chen, Qiushi, Li, Bingong, Zhang, Fengxiang
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.10.2020; Springer; Springer Nature B.V
• Subjects: Acetylcholine; Acetylcholine - pharmacology; Activation; Apoptosis; Autophagy; Biochemistry; Biomedical and Life Sciences; Cardiology; Cell Hypoxia - drug effects; Cell injury; Cell viability; Chloroquine; Coronary Vessels - metabolism; Coronary Vessels - pathology; Endothelial cells; Endothelial Cells - metabolism; Endothelial Cells - pathology; Endothelium; Fibrosis; Heart; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit - metabolism; Hypoxia-inducible factors; Inflammation; Life Sciences; Medical Biochemistry; Mesenchyme; Microvasculature; Microvessels - metabolism; Microvessels - pathology; Myocardium - metabolism; Myocardium - pathology; Neurotransmitters; NF-kappa B - metabolism; NF-κB protein; Oncology; Phagocytosis; Pretreatment; Prostaglandin E2; Stem cells; Vagus nerve; Hypoxia; Acetylcholine; Endothelial-to-mesenchymal transition; Autophagy; NF-κb inhibition
• ISSN: 0300-8177; 1573-4919; 1573-4919
• DOI: 10.1007/s11010-020-03811-w

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.