VEGF-C/VEGFR3 AND LYMPHATIC TRANSPORT OF CHOLESTEROL FROM ATHEROSCLEROTIC PLAQUE

VEGF-C/VEGFR3 与动脉粥样硬化斑块中胆固醇的淋巴转运

• 批准号: 8630012
• 负责人: Gwendalyn J Randolph
• 金额: $ 39.23万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-20 至 2017-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8630012
• 关键词: Accounting; Address; Adenovirus Vector; Affect; Anastomosis - action; Anatomy; Antibodies; Aorta; Apolipoprotein E; Area; Arterial Fatty Streak; Arteries; Atherosclerosis; Biliary; Binding; Biology; Cannulations; Cholesterol; Clinical; Data; Deuterium; Disease; Disease regression; Dose; Drainage procedure; Excision; Excretory function; Feces; Genetic; Goals; High Density Lipoprotein Cholesterol; High Density Lipoproteins; Human; Inflammation; Label; Laboratories; Left; Lesion; Ligands; Lipid Biochemistry; Lymph; Lymphangiogenesis; Lymphatic; Lymphatic vessel; Measures; Methodology; Methods; Mus; Mutant Strains Mice; Mutate; Operative Surgical Procedures; Pathway interactions; Peripheral; Physicians; Physiologic pulse; Plasma; Process; Recruitment Activity; Research Design; Research Personnel; Role; Route; Signal Transduction; Site; Skin; Smooth Muscle; Staging; Testing; Therapeutic; Thoracic Duct; Tissues; Transplantation; Vascular Endothelial Growth Factor C; Vascular Endothelial Growth Factor Receptor-2; Vascular Endothelial Growth Factor Receptor-3; Vascular Endothelial Growth Factors; cholesterol trafficking; hypercholesterolemia; improved; innovation; macrophage; monocyte; mouse model; mutant; public health relevance; research study; reverse cholesterol transport; tool

PROJECT SUMMARY Our long-term goal is to understand how to remove macrophages and cholesterol from plaques to promote disease regression. We recently discovered that lymphatic vessels serve as the conduits by which cholesterol is removed from the artery wall and other tissues. Reverse cholesterol transport (RCT) is the process by which cholesterol is mobilized from the body for excretion through the feces. With respect to atherosclerosis, the mobilization of cholesterol from macrophages for removal and excretion is most relevant. Over the years, many details emerged regarding how cholesterol is mobilized from macrophages to be loaded onto HDL (HDL-C). However, little was known about how HDL-cholesterol subsequently makes its way out of tissues, including sites like atherosclerotic plaques of the artery wall, to return to plasma before entering pathways for excretion. A handful of clinical or experimental observations led a few physicians in the early 1980's to propose a connection between impaired lymphatic transport and atherosclerosis. However, the quantitative importance of lymphatic vessels in RCT had not been examined, aside from a compelling study that estimated that the net flux of HDL-C through human lymph is substantial. Recently, we utilized experimental mouse models where the patency of lymphatic flow could be modulated by surgical or genetic methods. In skin, we were able to fully abrogate lymphatic flow allowing us to demonstrate that lymphatics are quantitatively the major route for cholesterol mobilization to plasma following macrophage RCT. In atherosclerosis-affected aortic walls, we also used a surgical approach to track deuterium-labeled cholesterol ([2H] D6-cholesterol; D6-cholesterol) from plaques in a pulse-chase manner. Aortas were surgically transplanted into recipients with re-anastomosis of the lymphatic vasculature blocked or not with anti-VEGFR3 mAb. This blockade significantly retained D6- cholesterol in the atherosclerotic aorta, suggesting a key role for lymphatic vessels in cholesterol mobilization from the aorta as observed in skin. In aim 1, we will take a critical next step with refined approaches that will allow us to better quantify the role of lymphatic vessels in cholesterol removal from the aorta and to assess whether the blockade on lymphatics is truly acting locally at the aortic wall. In preliminary data, we show that treating apoE-/- mice with VEGF-C, the ligand for VEGFR3, restores impaired lymphatic transport that occurs following hypercholesterolemia, allowing us to test the hypothesis that VEGF-C acts on lymphatic vessels to therapeutically sustain a critical route for cholesterol transport out of plaques after macrophage cholesterol efflux is stimulated. This hypothesis raises a fundamental question not yet addressed in the field: does effective plaque regression truly depend upon cholesterol removal from plaques, only upon cholesterol removal from macrophages, or perhaps neither? Our study design is ideal to address this fundamental issue while simultaneously digging deeply into a new concept that supporting lymphatic vessel function may help resolve inflammation in the atherosclerotic plaque.

项目概要 我们的长期目标是了解如何清除斑块中的巨噬细胞和胆固醇，以促进 疾病消退。我们最近发现，淋巴管是胆固醇输送的管道。 从动脉壁和其他组织中去除。胆固醇逆向转运（RCT）是这样的过程： 胆固醇从体内动员起来，通过粪便排出体外。就动脉粥样硬化而言， 从巨噬细胞中动员胆固醇以去除和排泄是最相关的。多年来，许多 关于胆固醇如何从巨噬细胞动员到高密度脂蛋白 (HDL-C) 上的细节浮出水面。 然而，人们对 HDL-胆固醇随后如何从组织中释放出来知之甚少，包括 动脉壁的动脉粥样硬化斑块等位点，在进入排泄途径之前返回血浆。 20 世纪 80 年代初，一些临床或实验观察结果导致一些医生提出了一种 淋巴运输受损与动脉粥样硬化之间的联系。然而，数量重要性 除了一项令人信服的研究估计净淋巴管未在随机对照试验中进行检查外 HDL-C 通过人体淋巴的通量很大。最近，我们利用实验小鼠模型，其中 淋巴流动的通畅可以通过手术或遗传方法来调节。在皮肤上，我们能够充分 消除淋巴流动使我们能够证明淋巴在数量上是主要途径 巨噬细胞 RCT 后胆固醇动员至血浆。在受动脉粥样硬化影响的主动脉壁中，我们还 使用手术方法追踪氘标记的胆固醇（[2H] D6-胆固醇；D6-胆固醇） 以脉冲追逐方式形成斑块。主动脉通过手术移植到受者体内，并重新吻合 抗 VEGFR3 mAb 是否阻断淋巴管系统。这种封锁显着保留了 D6- 动脉粥样硬化主动脉中的胆固醇，表明淋巴管在胆固醇动员中发挥关键作用 从皮肤观察到的来自主动脉的。在目标 1 中，我们将采取关键的下一步，采用精细的方法， 让我们能够更好地量化淋巴管在主动脉清除胆固醇过程中的作用并评估 对淋巴管的封锁是否真正作用于主动脉壁局部。在初步数据中，我们表明 用 VEGF-C（VEGFR3 的配体）治疗 apoE-/- 小鼠，可恢复受损的淋巴运输 高胆固醇血症后，使我们能够检验 VEGF-C 作用于淋巴管以 治疗性维持巨噬细胞胆固醇从斑块转运出的关键途径 外流受到刺激。这个假设提出了一个该领域尚未解决的基本问题： 有效的斑块消退确实取决于斑块中胆固醇的去除，而且仅取决于胆固醇的去除 来自巨噬细胞，或者两者都不是？我们的研究设计非常适合解决这个基本问题，同时 同时深入挖掘支持淋巴管功能的新概念可能有助于解决 动脉粥样硬化斑块中的炎症。