Viafara-Garcia Sergio M, Gualtero Diego F, Avila-Ceballos Daniel, Lafaurie Gloria I
Unit of Basic Oral Investigation UIBO, School of Dentistry, Universidad El Bosque, Bogotá, Colombia.
Eur J Oral Sci. 2018 Dec;126(6):476-484. doi: 10.1111/eos.12580. Epub 2018 Oct 24.
Eikenella corrodens is a gram-negative bacterium, and although primarily associated with periodontal infections or infective endocarditis, it has been identified in coronary atheromatous plaques. The effect of its lipopolysaccharide (LPS) on human coronary artery endothelial cells (HCAECs) is unknown. Our aim was to examine the mechanism underlying the inflammatory response in HCAECs stimulated with E. corrodens-LPS and to evaluate monocyte adhesion. Endothelial responses were determined by measuring the levels of chemokines and cytokines using flow cytometry. The surface expression of intercellular adhesion molecule 1 (ICAM-1) was determined using a cell-based ELISA, and the adhesion of THP-1 monocytes to HCAECs was also monitored. The involvement of toll-like receptors (TLRs) 2 and 4 was examined using TLR-neutralizing antibodies, and activation of extracellular signal-regulated kinase (ERK)1/2 and nuclear factor-kappa B (NF-κB) p65 were measured by western blotting and ELISA, respectively. Eikenella corrodens-LPS increased secretion of interleukin-8 (IL-8), monocyte chemotactic protein 1 (MCP-1), and granulocyte-macrophage colony-stimulating factor (GM-CSF), and expression of ICAM-1 on the surface of HCAECs, consistent with the increased adhesion of THP-1 cells. Moreover, E. corrodens-LPS interacted with TLR4, a key receptor able to maintain the levels of IL-8, MCP-1, and GM-CSF in HCAECs. Phosphorylation of ERK1/2 and activation of NF-κB p65 were also increased. The results indicate that E. corrodens-LPS activates HCAECs through TLR4, ERK, and NF-κB p65, triggering a pro-atherosclerotic endothelial response and enhancing monocyte adhesion.
腐蚀艾肯菌是一种革兰氏阴性菌，虽然主要与牙周感染或感染性心内膜炎有关，但已在冠状动脉粥样斑块中被发现。其脂多糖（LPS）对人冠状动脉内皮细胞（HCAECs）的影响尚不清楚。我们的目的是研究腐蚀艾肯菌LPS刺激的HCAECs炎症反应的潜在机制，并评估单核细胞黏附情况。通过流式细胞术测量趋化因子和细胞因子水平来确定内皮反应。使用基于细胞的ELISA测定细胞间黏附分子1（ICAM-1）的表面表达，并监测THP-1单核细胞与HCAECs的黏附情况。使用TLR中和抗体检查Toll样受体（TLRs）2和4的参与情况，分别通过蛋白质印迹法和ELISA测量细胞外信号调节激酶（ERK）1/2和核因子-κB（NF-κB）p65的激活情况。腐蚀艾肯菌LPS增加了白细胞介素-8（IL-8）、单核细胞趋化蛋白1（MCP-1）和粒细胞-巨噬细胞集落刺激因子（GM-CSF）的分泌，以及HCAECs表面ICAM-1的表达，这与THP-1细胞黏附增加一致。此外，腐蚀艾肯菌LPS与TLR4相互作用，TLR4是能够维持HCAECs中IL-8、MCP-1和GM-CSF水平的关键受体。ERK1/2的磷酸化和NF-κB p65的激活也增加了。结果表明，腐蚀艾肯菌LPS通过TLR4、ERK和NF-κB p65激活HCAECs，引发促动脉粥样硬化的内皮反应并增强单核细胞黏附。
