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 尽管目前有可用的治疗方法，但心血管疾病仍然是老年人死亡的主要原因。 美国的由于脂蛋白代谢失调导致心血管疾病， 迫切需要破译脂蛋白途径，包括那些由ANGPTL蛋白调节的途径， 导致心血管疾病拟议研究的长期目标是了解如何 ANGPTL蛋白调节脂质稳态以及这些蛋白如何在疾病中变得失调。 一种ANGPTL蛋白，肝因子ANGPTL 3，抑制内皮脂酶（EL）和脂蛋白 脂肪酶，从而调节血浆胆固醇和甘油三酯。本申请的目的是 确定ANGPTL 3调节EL的机制以及这种调节如何影响HDL 代谢和心血管疾病。本研究的中心假设是ANGPTL 3抑制EL 通过促进破坏其稳定性的结构变化，这种抑制可以防止病理性 导致动脉粥样硬化的HDL重塑。这一假设将通过两个 具体目的：1）确定ANGPTL 3介导的EL抑制对动脉粥样硬化和HDL的影响， 功能; 2）确定ANGPTL 3抑制EL的机制。目标1中的研究使用小鼠 表达仅抑制EL或LPL的突变ANGPTL 3等位基因。这些小鼠将与ApoE杂交 敲除小鼠，以确定ANGPTL 3介导的EL抑制和LPL的各自贡献 抑制动脉粥样硬化。这些小鼠也将用于确定EL的生理位置 使用组织磷脂酶活性测定抑制。放射性示踪实验将用于 确定ANGPTL 3对EL的抑制如何改变HDL-脂质分配，以及各种HDL功能 将使用测定来确定这种抑制如何改变HDL的抗动脉粥样硬化功能。在aim中 2，各种生化分析，包括磷脂酶活性测定，定点诱变，和 氢-氘交换质谱法，将用于探测功能的相互作用， ANGPTL 3与EL.所提出的研究在使用ANGPTL 3等位基因方面是创新的，ANGPTL 3等位基因仅抑制 LPL或仅抑制EL以解耦LPL和EL抑制的生理效应。拟议 研究是重要的，因为脂蛋白稳态对于心血管健康是必不可少的。因此，我们建议， 揭示ANGPTL 3如何以及在何处抑制EL活性，以及这种抑制如何影响HDL功能， 高密度脂蛋白代谢和动脉粥样硬化的进展将增加我们对 脂蛋白代谢是如何调节的。完成本研究概述的目标将产生广泛的 积极的影响，因为脂蛋白代谢有助于许多代谢疾病，因此 了解这些途径的调节剂，包括ANGPTL 3，如何最好地治疗 有针对性的治疗可能对改善这些疾病的结果产生广泛影响。