Oxidant resistant apoA1 in reverse cholesterol transport, inflammation and atherosclerosis

抗氧化剂 apoA1 在逆转胆固醇转运、炎症和动脉粥样硬化中的作用

基本信息

批准号：
9276118
负责人：
Jonathan D Smith
金额：
$ 39.63万
依托单位：
CLEVELAND CLINIC LERNER COM-CWRU
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-05-23 至 2020-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9276118
关键词：
ATP binding cassette transporter 1 Acute-Phase Reaction Affinity Aftercare Anti-Inflammatory Agents Anti-inflammatory Apolipoproteins Area Arterial Fatty Streak Atherosclerosis Bone Marrow Breeding Cell Adhesion Molecules Cell Membrane Proteins Cell Proliferation Cells Cholesterol Collagen Complete Blood Count Coronary Arteriosclerosis Data Development Endothelial Cells Endotoxins Environment Enzymes Epitopes Event Excretory function Gene Chips Genetic screening method Goals High Density Lipoprotein Cholesterol High Density Lipoproteins Human Human Genetics Impairment Individual Inflammation Inflammatory Knowledge Lead Lesion Lipids Lipoproteins Liver Measures Mediating Modeling Modification Molecular Profiling Monoclonal Antibodies Monocytosis Mus Myeloid Cells NF-kappa B Names Necrosis Neutrophilia Oxidants Oxides Pathway interactions Peripheral Peroxidases Pharmaceutical Preparations Phenylalanine Phospholipids Plasma Play Protein Isoforms Proteins Randomized Recombinants Reporting Resistance Risk Role Sepsis Series Site-Directed Mutagenesis Smooth Muscle Actin Staining Method Stimulus Testing Therapeutic Tissues Transgenic Mice Triglycerides Tryptophan Variant Zymosan antimicrobial atheroprotective cardiovascular disorder risk comparative efficacy cytokine disorder risk epidemiology study genetic variant histological stains humanized monoclonal antibodies loss of function macrophage monocyte mouse model neutrophil novel overexpression oxidation particle prevent protective effect reverse cholesterol transport therapeutic target

项目摘要

Abstract High levels of high density lipoprotein-cholesterol (HDL-C) are associated with lowered risk for cardiovascular disease (CVD) in epidemiological studies. Although several mechanisms may play a role in HDL’s protective effect, HDL and its major protein constituent, apolipoprotein-AI (apoA1), are critical components of the reverse cholesterol transport (RCT) pathway, in which cholesterol is removed from peripheral tissues and transferred to the liver for excretion. In the first step of the RCT pathway, lipid-poor apoA1 acts as an acceptor for cell cholesterol and phospholipids via the cell membrane protein ABCA1, generating nascent HDL. However, not all HDL is equivalent, and several studies have reported that individuals with coronary artery disease have HDL that is “dysfunctional” and no longer atheroprotective. The atherosclerotic lesion is a highly oxidative environment, and human lesions contain high levels of the antimicrobial enzyme myeloperoxidase (MPO), which we and others have shown can oxidize apoA1 and impair its function. We determined that the four tryptophan residues in human apoA1 (h-apoA1) are crucial in its MPO mediated loss of cholesterol acceptor function. We created a novel 4WF h-apoA1 variant, in which all four tryptophan residues are replaced by phenylalanine, which is resistant to MPO-mediated loss of function. We created and characterized transgenic mice that express high levels of the 4WF h-apoA1 isoform and found that these mice were resistant to inflammation. We also created human MPO transgenic mice, which over express MPO that can be further induced by zymosan treatment. Here we propose to characterize h-apoA1 modifications in mouse models and if these are modulated by inflammatory stimuli. We will also test whether the oxidant resistant 4WF apoA1 isoform can better protect from inflammation and sepsis, promote reverse cholesterol transport, delay atherosclerosis progression, and promote atherosclerosis regression in mice that over express MPO, creating an oxidative environment similar to that found in human lesions. Mechanistically, we will determine how the 4WF isoform protects mice from an acute phase response, and examine if the 4WF isoform better prevents myeloid cell proliferation and mobilization from the bone marrow leading to monocytosis and neutrophilia that are associated with atherosclerosis progression.

抽象的高水平的高密度脂蛋白胆固醇 (HDL-C) 与降低心血管疾病风险相关尽管有几种机制可能在 HDL 的保护作用中发挥作用，但流行病学研究中的疾病（CVD）。 HDL 及其主要蛋白质成分载脂蛋白-AI (apoA1) 是逆转效应的关键组成部分胆固醇转运（RCT）途径，其中胆固醇从外周组织中去除并转移到在 RCT 途径的第一步中，缺乏脂质的 apoA1 充当细胞的受体。胆固醇和磷脂通过细胞膜蛋白 ABCA1 产生新生的 HDL，但事实并非如此。所有 HDL 都是相同的，多项研究报告称，患有冠状动脉疾病的个体高密度脂蛋白“功能失调”且不再具有动脉粥样硬化作用动脉粥样硬化病变是一种高度氧化的病变。环境和人类病变部位含有高水平的抗菌酶髓过氧化物酶 (MPO)，我们和其他人已经证明它可以氧化 apoA1 并损害其功能。我们确定这四种。人 apoA1 (h-apoA1) 中的色氨酸残基对于 MPO 介导的胆固醇受体丢失至关重要我们创建了一种新的 4WF h-apoA1 变体，其中所有四个色氨酸残基都被替换为苯丙氨酸，它能抵抗 MPO 介导的功能丧失。我们创建并表征了转基因。表达高水平 4WF h-apoA1 亚型的小鼠，发现这些小鼠对我们还创建了人类 MPO 转基因小鼠，其过度表达 MPO，可以进一步抑制炎症。在这里，我们建议表征小鼠模型中的 h-apoA1 修饰。如果这些受到炎症刺激的调节，我们还将测试4WF apoA1是否具有抗氧化剂。同工型可以更好地预防炎症和败血症，促进胆固醇反向转运，延缓动脉粥样硬化进展，并促进过度表达 MPO 的小鼠动脉粥样硬化消退，从而产生从机制上讲，我们将确定与人类病变中发现的氧化环境类似的氧化环境。 4WF 同工型可保护小鼠免受急性期反应，并检查 4WF 同工型是否能更好地预防骨髓细胞增殖和动员导致单核细胞增多和中性粒细胞增多与动脉粥样硬化的进展有关。