Regulation of Endothelial Lipase and HDL Metabolism by ANGPTL3

ANGPTL3 对内皮脂肪酶和 HDL 代谢的调节

• 批准号: 10582972
• 负责人: BRANDON Scott Joseph DAVIES
• 金额: $ 54.01万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-13 至 2027-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10582972
• 关键词: ANGPTL3 gene; Affect; Alleles; Antiatherogenic; ApoE knockout mouse; Apolipoprotein E; Atherosclerosis; Biochemical; Biological Assay; Cardiovascular Diseases; Cardiovascular Pathology; Cause of Death; Cholesterol; Complex; Data; Deuterium; Disease; Disease Outcome; Dissection; Dyslipidemias; Goals; High Density Lipoprotein Cholesterol; High Density Lipoproteins; Homeostasis; Human; Hydrogen; Hydrolase; Hydrolysis; Knowledge; LIPG gene; Laboratories; Life; Lipase; Lipids; Lipoproteins; Location; Mass Spectrum Analysis; Mediating; Metabolic Diseases; Metabolism; Methods; Mission; Modeling; Mus; Mutagenesis; Pathologic; Pathway interactions; Phospholipase; Phospholipases A; Phospholipids; Physiological; Plasma; Proteins; Public Health; Radioactive Tracers; Regulation; Research; Role; Site-Directed Mutagenesis; Surface; Techniques; Temperature; Testing; Therapeutic; Time; Tissues; Triglycerides; United States; United States National Institutes of Health; burden of illness; cardioprotection; cardiovascular health; experimental study; improved; improved outcome; inhibitor; innovation; lipid metabolism; lipoprotein lipase; melting; mutant; prevent; therapeutic target

PROJECT SUMMARY Despite currently available treatments, cardiovascular disease remains the leading cause of death in the United States. As dysregulated lipoprotein metabolism contribute to cardiovascular disease, there is a critical need to decipher the lipoprotein pathways, including those regulated by ANGPTL proteins, that drive cardiovascular pathologies. The long-term goal of the proposed research is to understand how ANGPTL proteins regulate lipid homeostasis and how these proteins become dysregulated in disease. One ANGPTL protein, the hepatokine ANGPTL3, inhibits both endothelial lipase (EL) and lipoprotein lipase, and thus regulates both plasma cholesterol and triglycerides. The objective in this application is to identify the mechanisms by which ANGPTL3 regulates EL and how this regulation affects HDL metabolism and cardiovascular disease. The central hypothesis of this study is that ANGPTL3 inhibits EL by promoting structural changes that disrupt its stability, and that this inhibition prevents the pathologic remodeling of HDL that contributes to atherosclerosis. This hypothesis will be tested by pursuing two specific aims: 1) Determine the effects of ANGPTL3-mediated EL inhibition on atherosclerosis and HDL function; and 2) Identify the mechanism by which ANGPTL3 inhibits EL. The studies in aim 1 use mice that express mutant ANGPTL3 alleles that only inhibit EL or LPL. These mice will be crossed with ApoE knockout mice to determine the respective contributions of ANGPTL3-mediated EL inhibition and LPL inhibition to atherosclerosis. These mice will also be used to determine the physiologic locations of EL inhibition using tissue phospholipase activity assays. Radioactive tracer experiments will be used to determine how inhibition of EL by ANGPTL3 alters HDL-lipid partitioning, and a variety of HDL functional assays will be used to determine how this inhibition alters the anti-atherogenic functions of HDL. In aim 2, various biochemical analyses, including phospholipase activity assays, site-directed mutagenesis, and hydrogen-deuterium exchange mass spectrometry, will be used to probe the functional interactions of ANGPTL3 with EL. The proposed studies are innovative in their use of ANGPTL3 alleles that only inhibit LPL or only inhibit EL to decouple the physiological effects of LPL and EL inhibition. The proposed studies are significant because lipoprotein homeostasis is essential for cardiovascular health. Therefore, uncovering how and where ANGPTL3 inhibits EL activity, and how this inhibition impacts HDL function, HDL metabolism, and the progression of atherosclerosis will increase our fundamental understanding of how lipoprotein metabolism is regulated. Completion of the aims outlined in this study will have a broad positive impact as lipoprotein metabolism contributes to many metabolic diseases, and thus understanding how the regulators of these pathways, including ANGPTL3, can best be therapeutically targeted may have wide-reaching implications for improved outcomes for these diseases.

项目摘要 尽管目前可用的治疗方法，但心血管疾病仍然是死亡的主要原因 美国。由于失调的脂蛋白代谢有助于心血管疾病，因此 破译脂蛋白途径的迫切需要，包括受ANGPTL蛋白调节的脂蛋白途径， 驱动心血管病理。拟议研究的长期目标是了解 ANGPTL蛋白调节脂质稳态以及这些蛋白在疾病中的失调。 一种ANGPTL蛋白，肝素ANGPTL3抑制内皮脂肪酶（EL）和脂蛋白 脂肪酶，因此调节血浆胆固醇和甘油三酸酯。此应用程序的目的是 确定ANGPTL3调节EL的机制以及该调节如何影响HDL 代谢和心血管疾病。这项研究的中心假设是ANGPTL3抑制EL 通过促进破坏其稳定性的结构变化，并且这种抑制作用阻止了病理 HDL的重塑，导致动脉粥样硬化。该假设将通过追求两个来检验 具体目的：1）确定ANGPTL3介导的EL抑制对动脉粥样硬化和HDL的影响 功能; 2）确定ANGPTL3抑制EL的机制。 AIM 1的研究使用小鼠 该表达仅抑制EL或LPL的突变体angptl3等位基因。这些老鼠将与Apoe交叉 敲除小鼠，以确定Angptl3介导的EL抑制和LPL的各自贡献 抑制动脉粥样硬化。这些小鼠还将用于确定EL的生理位置 使用组织磷脂酶活性测定的抑制作用。放射性示踪剂实验将用于 确定ANGPTL3对EL的抑制是如何改变HDL脂质分区的，以及各种HDL功能 测定将用于确定这种抑制如何改变HDL的抗动脉粥样硬化功能。目标 2，各种生化分析，包括磷脂酶活性测定，定向诱变和 氢 - 居民交换质谱法将用于探测 angptl3与el。拟议的研究对仅抑制Angptl3等位基因的使用是创新的 LPL或仅抑制EL可以使LPL和EL抑制的生理作用解脱。提议 研究很重要，因为脂蛋白稳态对于心血管健康至关重要。所以， 发现ANGPTL3如何和何处抑制EL活性，以及​​这种抑制如何影响HDL功能， HDL代谢以及动脉粥样硬化的进展将增加我们对 如何调节脂蛋白代谢。这项研究中概述的目标的完成将有广泛的 脂蛋白代谢的积极影响会导致许多代谢疾病，因此 了解包括Angptl3在内的这些途径的调节器如何最好地在治疗上进行 有针对性的可能对这些疾病的改善结果具有广泛的影响。