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: 8792548
• 负责人: Gwendalyn J Randolph
• 金额: $ 37.47万
• 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/8792548
• 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; Health; 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; research study; reverse cholesterol transport; tool

DESCRIPTION (provided by applicant): 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 roe 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 treatin 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.

描述（由申请人提供）：我们的长期目标是了解如何去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从动脉壁和其他组织中清除胆固醇的管道。胆固醇反向转运（RCT）是胆固醇从体内动员并通过粪便排出体外的过程。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，关于胆固醇如何从巨噬细胞动员到高密度脂蛋白 (HDL-C) 上的许多细节浮出水面。然而，人们对高密度脂蛋白胆固醇随后如何从组织（包括动脉壁动脉粥样硬化斑块等部位）中排出，在进入排泄途径之前返回血浆的情况知之甚少。 20 世纪 80 年代初，一些医生根据一些临床或实验观察结果提出，淋巴运输受损与动脉粥样硬化之间存在联系。然而，除了一项令人信服的研究估计 HDL-C 通过人体淋巴的净通量是巨大的之外，RCT 中淋巴管的定量重要性尚未得到检验。最近，我们利用实验小鼠模型，其中淋巴流动的通畅性可以通过手术或遗传方法调节。在皮肤中，我们能够完全消除淋巴流动，从而证明淋巴管是巨噬细胞 RCT 后定量胆固醇动员至血浆的主要途径。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以脉冲追踪方式追踪斑块中的氘标记胆固醇（[2H] D6-胆固醇；D6-胆固醇）。通过手术将主动脉移植到接受者体内，并用抗 VEGFR3 单克隆抗体重新吻合或不阻断淋巴管系统。这种阻断显着地保留了动脉粥样硬化主动脉中的 D6-胆固醇，表明其具有关键作用 用于在皮肤中观察到从主动脉动员胆固醇的淋巴管。在目标 1 中，我们将采取关键的下一步，采用精细的方法，使我们能够更好地量化从主动脉去除胆固醇过程中的淋巴管鱼卵，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，可恢复高胆固醇血症后发生的受损淋巴运输，使我们能够检验 VEGF-C 作用于淋巴管以治疗性维持淋巴管运输的假设。刺激巨噬细胞胆固醇流出后，胆固醇从斑块转运出的关键途径。这一假设提出了一个该领域尚未解决的基本问题：有效的斑块消退是否真正取决于斑块中胆固醇的去除，仅取决于巨噬细胞中胆固醇的去除，或者两者都不是？我们的研究设计非常适合解决这一基本问题，同时深入探讨支持淋巴管功能可能有助于解决动脉粥样硬化斑块炎症的新概念。