Fritzenwanger Michael, Foerster Martin, Meusel Katharina, Jung Christian, Figulla Hans R
Department of Internal Medicine I, Friedrich-Schiller-University Jena, Jena, Germany.
Chin Med J (Engl). 2008 Dec 20;121(24):2592-8.
In addition to elevated concentrations of cytokines, patients with congestive heart failure (CHF) show endothelial dysfunction and increased plasma concentrations of adhesion molecules like intercellular adhesion molecule-1 (ICAM-1). Furthermore, the concentration of cardiotrophin-1 (CT-1)--a cytokine of the interleukin-6 superfamily--is increased in CHF. We tested the hypothesis whether CT-1 is able to induce ICAM-1 in human umbilical vein endothelial cells (HUVEC). Furthermore we examined the signalling mechanisms of CT-1 mediated ICAM-1 expression.
Confluent layers of HUVEC were incubated with increasing concentrations of CT-1 (5 to 100 ng/ml) for different periods. ICAM-1 mRNA was determined by real-time polymerase chain reaction (PCR) and ICAM-1 surface expression by fluorescence-activated cell sorter (FACS) analysis and soluble ICAM-1 (sICAM-1) in the culture supernatant by enzyme linked immunosorbent assay (ELISA). To clarify the signalling pathway of CT-1 induced ICAM-1 expression we used various inhibitors of possible signal transducing molecules, electromobility shift assay (EMSA) and Western blot analysis.
CT-1 induced ICAM-1 mRNA (1.8 +/- 0.8 fold increase compared to unstimulated cells after 6 hours) and protein (1.4 +/- 0.2 fold increase compared to unstimulated cells after 48 hours) in HUVEC in a time- and concentration-dependent manner. EMSA experiments show that CT-1 causes nuclear factor (NF) kappaB activation. Because parthenolide could inhibit CT-1 induced ICAM-1 expression NFkappaB activation is required in this pathway. CT-1 did not activate extracellular signal regulated kinases (ERK), c-Jun N-terminal kinase (JNK) and p38.
CT-1 is able to induce ICAM-1 in endothelial cells by NFkappaB activation. These results may explain in part elevated ICAM-1 concentrations in patients with CHF and endothelial dysfunction.
除细胞因子浓度升高外，充血性心力衰竭（CHF）患者还表现出内皮功能障碍以及血浆中细胞间黏附分子 -1（ICAM -1）等黏附分子浓度升高。此外，心肌营养素 -1（CT -1）——白细胞介素 -6超家族的一种细胞因子——在CHF患者中的浓度也升高。我们检验了CT -1是否能够在人脐静脉内皮细胞（HUVEC）中诱导ICAM -1表达这一假设。此外，我们研究了CT -1介导ICAM -1表达的信号传导机制。
将融合的HUVEC层与不同浓度（5至100 ng/ml）的CT -1孵育不同时间。通过实时聚合酶链反应（PCR）测定ICAM -1 mRNA，通过荧光激活细胞分选仪（FACS）分析测定ICAM -1表面表达，并通过酶联免疫吸附测定（ELISA）测定培养上清液中的可溶性ICAM -1（sICAM -1）。为阐明CT -1诱导ICAM -1表达的信号通路，我们使用了各种可能的信号转导分子抑制剂、电泳迁移率变动分析（EMSA）和蛋白质印迹分析。
CT -1以时间和浓度依赖性方式在HUVEC中诱导ICAM -1 mRNA（6小时后与未刺激细胞相比增加1.8±0.8倍）和蛋白质（48小时后与未刺激细胞相比增加1.4±0.2倍）。EMSA实验表明CT -1导致核因子（NF）κB活化。因为小白菊内酯可抑制CT -1诱导的ICAM -1表达，所以该途径需要NFκB活化。CT -1未激活细胞外信号调节激酶（ERK）、c -Jun氨基末端激酶（JNK）和p38。
CT -1能够通过NFκB活化在内皮细胞中诱导ICAM -1表达。这些结果可能部分解释了CHF患者中ICAM -1浓度升高和内皮功能障碍的原因。
