ENDOTHELIAL DYSFUNCTION: FORMATION OF MICROPARTICLES

内皮功能障碍：微粒的形成

• 批准号: 6942957
• 负责人: SERGEY BRODSKY
• 金额: $ 1.1万
• 依托单位: NEW YORK MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2005-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6942957
• 关键词: biomarker; blood coagulation; blood coagulation disorders; blood vessel disorder; diabetes mellitus; flow cytometry; genetically modified animals; glucose; immunomagnetic separation; intermolecular interaction; laboratory mouse; laboratory rat; nitric oxide; particle; pathologic process; plasminogen activator inhibitors; protein binding; tissue /cell culture; vascular endothelium; vasoconstriction; western blottings

DESCRIPTION (provided by applicant): The proposed project should enhance candidate's previous experience in vascular biology and diabetes and develop the candidate into an independent researcher. While Pl's experience with in vivo and in vitro experimental techniques will help to conduct the presented project, its completion will significantly enrich candidate's knowledge in cell biology and physiology as well. Endothelial cell dysfunction (ECD) is a common precursor and denominator of various pathologic conditions, including stroke, hypertension, myocardial infarction and diabetes mellitus. The established hallmarks of endothelial cell dysfunction are a deficiency in the production or bioavailability of nitric oxide (NO), an increased level of plasminogen activator inhibitor-1 (PAl-1), and a presence of a pro-coagulant state. We have previously demonstrated that elevated level of PAl-1 results in a decreased production of NO by cultured endothelial cells, as well as an increased production of microparticies stained with Annexin V - evidence for the expression of anionic phospholipids. This was accompanied by the accelerated generation of thrombin by microparticles. PAl-1 knockout mice presented with a significantly decreased number of circulating microparticles and a marked increase in the number of microparticles after PAl-1 injection. Combined with recent findings of elevated levels of circulating endothelial microparticles in patients with acute coronary syndrome and diabetes, our data suggest that a) microparticles may be a consequence of ECD and contribute to a procoagulant state accompanying these diseases and b) raise the question whether increased levels of circulating microparticles may contribute to the development and maintenance of endothelial cell dysfunction. Based on these findings we hypothesize that: 1) increased microparticle formation by stressed endothelial cells is not only a novel marker of, but also a contributor to endothelial dysfunction and 2) elevated level of PAl-1 (a recognized marker of endothelial dysfunction) leads to increased formation of microparticles with pro-coagulant properties. The current proposal seeks to 1) establish a novel pathophysiolgical mechanism of endothelial dysfunction - formation of microparticles by stressed endothelial cells; 2) obtain information on the population of circulating microparticles produced by endothelial cells in diabetes mellitus; 3) to investigate possible links between identified markers of endothelial dysfunction, namely elevated levels of PAl-1 and increased coagulant activity. To accomplish these goals, microparticle formation will be studied using fluorescence-activated cell sorting in vitro (in endothelial cells stressed with high glucose or PAl-1) and in vivo (in Zucker diabetic rats). The link between PAl-1 and increased coagulant activity will be studied in vivo using PAl-1 knockout mice and in vitro using endothelial cell cultures. The proposed studies may provide novel information on the contribution of microparticles to the pathophysiology of endothelial cell dysfunction and coagulation abnormalities.

描述（由申请人提供）： 拟议的项目应增强候选人以前在血管生物学和糖尿病方面的经验，并将候选人培养成为一名独立的研究人员。虽然 Pl 在体内和体外实验技术方面的经验将有助于开展所提出的项目，但其完成也将显着丰富候选人在细胞生物学和生理学方面的知识。 内皮细胞功能障碍（ECD）是各种病理状况的常见前兆和分母，包括中风、高血压、心肌梗塞和糖尿病。内皮细胞功能障碍的既定标志是一氧化氮(NO)的产生或生物利用度不足、纤溶酶原激活剂抑制剂-1(PA1-1)水平增加以及促凝血状态的存在。我们之前已经证明，PAl-1水平升高导致培养的内皮细胞NO产生减少，以及用膜联蛋白V染色的微粒产生增加——阴离子磷脂表达的证据。这伴随着微粒加速凝血酶的产生。 PAl-1敲除小鼠在注射PAl-1后表现出循环微粒数量显着减少并且微粒数量显着增加。结合最近关于急性冠脉综合征和糖尿病患者循环内皮微粒水平升高的发现，我们的数据表明：a) 微粒可能是 ECD 的结果，并导致伴随这些疾病的促凝血状态；b) 提出了这样的问题：循环微粒的水平可能有助于内皮细胞功能障碍的发展和维持。基于这些发现，我们假设：1)应激内皮细胞增加的微粒形成不仅是内皮功能障碍的新标志物，而且也是内皮功能障碍的一个促成因素；2)PAl-1(内皮功能障碍的公认标志物)水平升高导致增加具有促凝特性的微粒的形成。目前的提议旨在1）建立内皮功能障碍的新病理生理机制——应激内皮细胞形成微粒； 2)获得糖尿病中内皮细胞产生的循环微粒数量的信息； 3)研究已识别的内皮功能障碍标志物之间可能的联系，即PAl-1水平升高和凝血活性增加。为了实现这些目标，将使用荧光激活细胞分选在体外（在高葡萄糖或PAl-1应激的内皮细胞中）和体内（在Zucker糖尿病大鼠中）研究微粒形成。将使用PAl-1敲除小鼠在体内研究PAl-1和增加的凝血活性之间的联系，并使用内皮细胞培养物在体外研究PAl-1和增加的凝血活性之间的联系。拟议的研究可能提供关于微粒对内皮细胞功能障碍和凝血异常的病理生理学贡献的新信息。

项目成果

Dynamics of circulating microparticles in liver transplant patients.

• 发表时间: 2008-09
• 期刊: Journal of gastrointestinal and liver diseases : JGLD
• 作者: S. Brodsky;M. Facciuto;D. Heydt;Jun Chen;H. Islam;M. Kajstura;G. Ramaswamy;M. Aguero-Rosenfeld

Glycated Collagen I (GC) impairs angiogenesis in vitro: a study using an innovative chamber for cell research.

糖化胶原 I (GC) 会损害体外血管生成：一项使用创新室进行细胞研究的研究。

• DOI: 10.1016/j.diabres.2006.10.003
• 发表时间: 2007
• 期刊: Diabetes research and clinical practice
• 影响因子: 5.1
• 作者: Brodsky,SergeyV;Merks,RoelandMH;Mendelev,Natalia;Goo,Cara;Chen,Jun
• 通讯作者: Chen,Jun