GENETICS OF ARTERIAL AND PROGENITOR ENDOTHELIAL CELLS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 传统的风险因素(如脂蛋白、炎症、氧化应激)只能解释动脉粥样硬化性疾病风险的一半。我们认为动脉壁对循环危险因素的反应占剩余风险的很大比例。动脉壁是血管病变发生的部位，决定了血管疾病的内源性易感性。此外，血管损伤后循环内皮祖细胞的动员在动脉粥样硬化的发生和发展中起着重要作用。在这个项目中，我们将首先检验这样一个假设，即遗传变异是内皮细胞对致动脉粥样硬化刺激反应的主要决定因素，因此在很大程度上导致了对动脉粥样硬化的易感性的变化。通过动脉活检，我们将从405只纯种狒狒身上收集大血管内皮细胞(ECs)，并在体外对这些细胞进行促动脉粥样硬化的挑战。检测内皮细胞激活前后eNOS、VCAM-1、ICAM-1、E-选择素、vWF、MCP-1的mRNA和蛋白水平及细胞凋亡率。其次，我们将检验这样的假设，即循环中的CEPC的基本数量是由基因控制的，而为应对血管损伤而动员的CEPC的数量也是由基因控制的。分别于伤前和伤后7wk采集450只基础饮食和80只在体股动脉结扎股动脉损伤前后的血，并用流式细胞仪对损伤前和伤后72小时血中CEPC的数量进行定量，以评估动员的祖细胞的诱导情况。结果将接受全基因组扫描，以确定含有基因的染色体区域。 影响内皮细胞功能或内皮祖细胞数量。第三，我们将在一项研究中验证EC功能特性和CEPC数预测动脉粥样硬化病变易感性的假设，该研究对111只在尸检和病变评估之前喂食致动脉粥样硬化食物2年的狒狒进行了研究。第四，我们将检验假设 一种致动脉粥样硬化的饮食阻碍了CEPC的分化能力，方法是在饮食挑战2年前和期间，以及股动脉活检前后，对120只狒狒的CEPC进行功能分析。最终目标是确定调控对动脉粥样硬化风险因子的功能性反应的基因。 动脉壁内的成熟内皮细胞和血液中循环的前体内皮细胞。我们的项目将建立一个非人类灵长类动物模型，可用于直接评估动脉壁内皮功能的血管疾病的药理学和介入性研究。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Traditional risk factors (e.g., lipoproteins, inflammation, oxidative stress) explain only half the risk of atherosclerotic disease. We believe that the response of the arterial wall to circulating risk factors accounts for a significant proportion of the remaining risk. Arterial wall is where the vascular pathological changes occur, and it determines endogenous susceptibility to vascular diseases. Furthermore, mobilization of circulating endothelial progenitor cells (CEPCs) in response to vascular injury plays a major role in the initiation and progression of atherosclerosis. In this project, we will first test the hypothesis that genetic variation is the major determinant of endothelial responses to atherogenic stimuli and consequently is largely responsible for variation in susceptibility to atherosclerosis. Using arterial biopsies, we will collect macrovascular endothelial cells (ECs) from 405 pedigreed baboons, and will subject these cells to in vitro pro-atherogenic challenges. We will measure markers of endothelial dysfunction including mRNA and protein levels of eNOS, VCAM-1, ICAM-1, E-Selectin, vWF and MCP-1, and percentage of apoptosis before and after endothelial cells are activated. Second, we will test the hypotheses that the basal number of circulating CEPCs is regulated genetically, and that the number of mobilized CEPCs in response to vascular injury is also genetically controlled. We will collect blood prior to and after in vivo vascular injury by femoral artery ligation from 450 baboons on basal diet and 80 after a 7-wk challenge and we will quantify CEPC number in the blood by flow cytometry before and 72 hr post injury to evaluate the induction of mobilized progenitor cells. The results will be subjected to genome wide scans to identify chromosomal regions that harbor genes affecting endothelial function, or number of CEPCs. Third, we will test the hypothesis that EC functional properties and CEPC numbers predict susceptibility to atherosclerotic lesions in a study of 111 baboons fed atherogenic diet for 2 yr prior to necropsy and assessment of lesions. Fourth, we will test the hypothesis that an atherogenic diet hampers CEPC differentiation capacity by conducting functional assays on cultured CEPCs from 120 baboons before and during a 2-yr dietary challenge, and before and after femoral artery biopsy. The ultimate goal is to identify genes that regulate functional responses to atherogenic risk factors in mature endothelial cells lining arterial wall and in progenitor endothelial cells circulating in the blood. Our project will establish a nonhuman primate model that can be used for pharmacological and interventional investigations of vascular diseases with direct assessment of arterial wall endothelial function.