Importance of the EGF receptor and the smooth muscle-endothelial interaction for the effects of obesity-associated milieu changes on vascular cells.

肥胖频率的增加是心血管疾病流行的重要原因。肥胖相关环境改变（OAMC）可直接影响血管壁稳态。前期项目的工作显示了EGF受体（EGFR）作为信号积分器在血管信息处理中的重要作用。我们的数据表明，血管肌(VSMC)-EGFR有助于高脂肪饮食（HFD）诱导的血管和肾脏改变。EGFR/ErbB2-ROCK-MRTF-SRF信号轴的增强和线粒体功能障碍在此起重要作用。此外，VSMC和内皮细胞（EC）之间存在依赖于VSMC- egfr的相互作用。另一方面，EC-EGFR对于血管功能本身以及hfd引起的损伤的重要性较小，甚至部分相反。观察到egfr介导的TGFβ和CTGF在原发性VSMC中的表达可能是相互作用的机制。在初步实验中，我们能够证明EGF对原发性VSMC（野生型但不是EGFR-KO）转录组的影响被葡萄糖增强，并且在骨桥蛋白表达方面存在协同作用，骨桥蛋白也是VSMC- ec相互作用的候选物。目的：分析EGFR在OAMC对原发性VSMC和EC的影响及细胞相互作用中的重要性。要检查的OAMC成分包括代谢应激（葡萄糖、游离脂肪酸）和体液应激（血管紧张素II、去甲肾上腺素）。行动需要：我们的主要工作假设认为VSMC- egfr对于VSMC和EC的病理性血管变化是必要的。在这里，VSMC和EC之间发生依赖于VSMC- egfr的相互作用。由此导致的EC改变还包括EC- egfr的积极作用减弱和受影响EC对VSMC的有害反馈。现在必须检查相互作用假说，EGFR的参与及其与人类血管细胞的相关性，并确定信息传递的机制。行动概念：我们将在小鼠和人的原代VSMC和EC单培养和共培养中进行比较实验。通过比较共培养的EGFR- ko动物和WT动物的细胞，小鼠模型允许以细胞特异性的方式研究EGFR的作用。转基因小鼠模型的细胞对病理生理过程的机制理解做出了重大贡献。然而，转移到人细胞往往是不可能的，因此使用离体原代人细胞培养系统是必要的。然后在人体模型中使用EGFR抑制剂。为检验相应的假设，计划了以下工作包：增殖、衰老、细胞死亡；2. 能量稳态;3. 细胞外基质;4. 炎症;5 6。细胞间和细胞内信号转导。关于信息传递，通过媒介分析和干预实验来检查细胞间的通信。

The increasing frequency of obesity contributes significantly to the prevalence of cardiovascular diseases. Obesity-associated milieu changes (OAMC) can directly affect vascular wall homeostasis. Work from the previous project period shows the important role of EGF receptor (EGFR), as a signal integrator in vascular information processing. Our data show that the vascular muscle (VSMC)-EGFR contributes to high-fat diet (HFD)-induced vascular and renal changes. The potentiation of the EGFR/ErbB2-ROCK-MRTF-SRF signaling axis and mitochondrial dysfunction play an important role here. In addition, there is a VSMC-EGFR-dependent interaction between VSMC and endothelial cells (EC). The EC-EGFR, on the other hand, is of lesser and partly contrary importance for vascular function per se, as well as for HFD-induced damage. The observed EGFR-mediated expression of TGFβ and CTGF in primary VSMC represents a possible mechanism of interaction. In preliminary experiments we were able to show that the effect of EGF on the transcriptome of primary VSMC (wildtype but not EGFR-KO) is enhanced by glucose and that there is, among other things, a synergism with regard to the expression of osteopontin, also a candidate for the VSMC-EC interaction.Objective: Analyzing the importance of EGFR for the effects of OAMC on primary VSMC and EC and of cellular interaction. The components of OAMC to be examined include metabolic stress (glucose, free fatty acids) and humoral stress (angiotensin II, norepinephrine).Action need: Our main working hypotheses state that the VSMC-EGFR is necessary for pathological vascular changes in VSMC and EC. Here, a VSMC-EGFR-dependent interaction between VSMC and EC takes place. Resulting alterations of EC can also include a weakening of positive effects of EC-EGFR and detrimental feedback of affected EC on VSMC. The interaction hypothesis, the involvement of EGFR and its relevance for human vascular cells must now be examined and the mechanisms of information transfer identified.Action concept: We will carry out comparative experiments with murine and human primary VSMC and EC in mono- and co-culture. The mouse models allow the role of EGFR to be investigated in a cell-specific manner by comparing cells from EGFR-KO animals and WT animals in coculture. Cells of transgenic mouse models have contributed significantly to the mechanistic understanding of pathophysiological processes. However, the transfer to human cells was often not possible, so that the use of ex vivo primary human cell culture systems is necessary. EGFR inhibitors are then used in the human model. The following work packages for testing the corresponding hypotheses are planned: 1. proliferation, senescence, cell death; 2. energy homeostasis; 3. extracellular matrix; 4. inflammation; 5&6. inter- and intracellular signal transduction. With regard to information transfer, intercellular communication is exam-ined by means of media analysis and intervention experiments.