RAGE, Macrophages & HDL Biology

愤怒，巨噬细胞

• 批准号: 9265499
• 负责人: ANN MARIE SCHMIDT
• 金额: $ 40.87万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9265499
• 关键词: ATP binding cassette transporter 1; Address; Advanced Glycosylation End Products; Age; Apolipoprotein E; Apolipoproteins; Arterial Fatty Streak; Atherosclerosis; Attenuated; Biology; Blood Vessels; Bone Marrow; Cells; Cholesterol; Data; Data Analyses; Diabetes Mellitus; Diabetic mouse; Down-Regulation; Excision; Excretory function; Gene Expression; Genes; Genetic; Genomics; High Density Lipoproteins; Human; Immune; In Vitro; Inflammation; Inflammatory; Inflammatory Response; Knockout Mice; Lead; Ligands; Link; Liver; Low Density Lipoprotein Receptor; Maintenance; Mediating; Membrane; Messenger RNA; Metabolism; MicroRNAs; Molecular; Mus; Oxidative Stress; Pathway interactions; Pattern; Peripheral; Property; Proteins; Regulation; Role; Signal Transduction; Small Interfering RNA; Testing; Therapeutic; Time; Tissues; Wild Type Mouse; Work; base; cardiovascular health; cholesterol transporters; design; diabetic; experimental study; gain of function; glycation; human subject; in vivo; insight; knock-down; loss of function; macrophage; migration; non-diabetic; novel; novel therapeutics; oxidation; programs; protective effect; public health relevance; receptor; receptor for advanced glycation endproducts; reverse cholesterol transport; scaffold

DESCRIPTION (provided by applicant): High density lipoprotein (HDL) exerts multiple vascular-protective effects in vivo. HDL promotes excess cholesterol efflux from peripheral tissues via transport to the liver for excretion, suppresses oxidative stress and inflammation, and enhances endothelial function. In murine and human subjects, receptor for AGE (RAGE) expression is upregulated in vascular and immune cells in non-diabetic and diabetic atherosclerosis. Studies in non-diabetic and diabetic LDL receptor (LDLR) null mice and apolipoprotein Apoe null mice revealed that blockade of ligand-RAGE interaction resulted in significant suppression of atherosclerosis. In this application, we will link for the first time ke roles for the receptor for advanced glycation end products (RAGE) to the biology of HDL prompted by three novel discoveries: first, RAGE deficient bone marrow derived macrophages (BMDMs) from non-diabetic or diabetic mice displayed significantly increased cholesterol efflux to ApoA1 and to HDL2 compared to RAGE expressing BMDMs. In parallel, mRNA levels for the two key cholesterol transporters, Abca1 and Abcg1, were H2-fold and >250-fold higher in RAGE null BMDMs vs. wild- type BMDMs, respectively. When RAGE expression was reduced by siRNAs in THP-1 human macrophages, significantly higher cholesterol efflux to ApoA1 and HDL2 resulted compared to treatment with scramble siRNAs. Second, in RAGE null BMDMs, levels of Mir33 were significantly lower than those found in wild-type mice control BMDMs; knockdown of RAGE expression in THP-1 macrophages resulted in highly significant reduction in MIR33 levels. Intriguingly, mRNA and protein levels of the Mir33 "host gene" (Srebf2) did not differ between RAGE-expressing vs. RAGE null BMDMs, suggesting unique mechanisms of RAGE-dependent regulation of Mir33. Third, in seeking to identify the mechanisms by which macrophage RAGE attenuates tissue-damaging inflammatory responses, we discovered that incubation of BMDMs with RAGE ligand AGEs enhanced expression of pro-inflammatory "M1" type macrophage markers and reduced expression of "M2" type macrophage markers in a RAGE-dependent manner. We hypothesize that RAGE interferes with the benefits of HDL metabolism by reducing expression of key cholesterol transporters, consequences of which include: (1). reduced removal of cholesterol from atherosclerotic plaques leading to accelerated progression and reduced regression of atherosclerosis; and (2). maintenance of cholesterol-rich membrane properties that support RAGE-dependent signal transduction mechanisms and thereby potentiate "M1" macrophage polarization and macrophage migration. We will test these concepts in this application using in vitro and in vivo approaches to discern the molecular mechanisms by which RAGE impacts regulation of Mir33/Abca1/Abcg1 and macrophage cholesterol efflux, polarization and migration and in vivo, reverse cholesterol transport and atherosclerosis. Taken together, this work will uncover novel therapeutic strategies to enhance HDL function and cardiovascular health.

描述（由申请人提供）：高密度脂蛋白（HDL）在体内发挥多种血管保护作用。 HDL通过运输到肝脏以排泄，抑制氧化应激和炎症，并促进外周组织中过量的胆固醇外排。 增强内皮功能。在鼠和人类受试者中，在非糖尿病和糖尿病动脉粥样硬化中的血管和免疫细胞中，年龄（RAGE）表达的受体上调。对非糖尿病和糖尿病LDL受体（LDLR）无效小鼠和载脂蛋白APOE NULL小鼠的研究表明，配体相互作用的阻断导致了对动脉粥样硬化的显着抑制。在此应用中，我们将首次链接到高级糖基化终产物（RAGE）的受体的首次链接到HDL的生物学，这是由三个新颖发现的：第一个新发现的发现：从非糖尿病或糖尿病小鼠造成的骨髓衍生出的骨髓不足（BMDMS）从非糖尿病或糖尿病小鼠中显着提高了胆固醇的表达BM和Apoa和apoa和hdl2。同时，两个关键胆固醇转运蛋白ABCA1和ABCG1的mRNA水平分别为H2倍和> 250倍，在RAGE NULL BMDMS与野生型BMDM中分别高250倍。当THP-1人类巨噬细胞中siRNA降低愤怒表达时，与用cramble siRNA的处理相比，胆固醇对ApoA1和HDL2的胆固醇排出明显更高。其次，在愤怒的零BMDM中，miR33的水平明显低于野生型小鼠控制BMDM的水平。 THP-1巨噬细胞中愤怒表达的敲低导致miR33水平的显着降低。有趣的是，miR33“宿主基因”（SREBF2）的mRNA和蛋白质水平在表达愤怒与rage null bmdms之间没有差异，这表明了mir33的愤怒依赖性调节的独特机制。第三，在寻求确定巨噬细胞愤怒减轻组织炎症反应的机制时，我们发现BMDM与RAIGE配体年龄的孵育增强了促炎性“ M1”类型巨噬细胞标记的表达，并降低了“ M2”类型的巨噬细胞标记在Rage依赖性的方式中。我们假设愤怒通过减少关键胆固醇转运蛋白的表达来干扰HDL代谢的益处，其后果包括：（1）。减少了从动脉粥样硬化斑块中去除胆固醇，导致进展加速并减少动脉粥样硬化的消退； （2）。维持富含胆固醇的膜特性，这些特性支持依赖RAGE的信号转导机制，从而增强“ M1”巨噬细胞极化和巨噬细胞迁移。我们将使用体外和体内方法在此应用中测试这些概念，以辨别愤怒影响MiR33/ABCA1/ABCG1和巨噬细胞胆固醇外流的分子机制，极化和迁移，体内，反向胆固醇的转运和动脉粥样硬化。综上所述，这项工作将发现新颖的治疗策略，以增强HDL功能和心血管健康。