Malondialdehyde-induced Endothelial Dysfunction in Atherosclerosis

丙二醛诱导的动脉粥样硬化内皮功能障碍

基本信息

批准号：
10449472
负责人：
Xiaoli Sun
金额：
$ 24.9万
依托单位：
UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10449472
关键词：
Alzheimer&apos s Disease Amino Acids Anti-Inflammatory Agents Antibodies Area Atherosclerosis Award Binding Blood Blood Vessels Cell physiology Cells Cellular biology Cholesterol Coronary artery Coronary heart disease Data Disease Electron Transport Endothelial Cells Endothelium Environment Enzymes Equilibrium Event Exhibits Faculty Fc domain Free Radicals Functional disorder Gene Expression Goals Heme Homeostasis Human Hyperlipidemia Immunoglobulin G Immunoglobulin M Impairment In Vitro Infiltration Inflammation Inflammatory Intercellular Junctions Knockout Mice Knowledge Lesion Lesion by Morphology Libraries Lipid Peroxidation Lipoproteins Malondialdehyde Measures Mediating Mentors Metabolism Molecular Mus Necrosis Outcome Pathogenesis Pathogenicity Pathologic Pathway interactions Permeability Phage Display Phase Physiological Plant Roots Plasma Polyunsaturated Fatty Acids Positioning Attribute Proteins Research Research Personnel Resources Role Site Sp1 Transcription Factor Stains Steatohepatitis Stimulus Synthetic Genes Transgenic Mice Vascular Permeabilities activating transcription factor atherogenesis base drug metabolism endothelial dysfunction experimental study feeding heme biosynthesis improved in silico in vivo macrophage mouse model new therapeutic target novel therapeutic intervention oxidation oxidized lipid oxygen transport prevent promoter protein function protein structure synthetic enzyme tenure track therapeutic target therapeutically effective transcriptome vascular endothelial dysfunction vascular inflammation western diet

项目摘要

PROJECT SUMMARY/ABSTRACT Malondialdehyde (MDA) is a ubiquitous and highly reactive end product of non-enzymatic lipid peroxidation, which is a central event in atherogenesis. MDA can covalently modify proteins, and is thought to be pro- inflammatory and atherogenic. It was shown that blood MDA level is correlated to coronary heart disease. However, its exact roles in atherogenesis are unknown as there were no in vivo strategies to specifically neu- tralize it. We recently generated IK17-scFv transgenic mice, which express a single chain variable fragment (scFv) of the human IK17 antibody that targets MDA. My preliminary studies found that IK17-scFv ameliorated Western diet (WD)-induced atherosclerosis in Ldlr-/- mice. MDA staining of lesion cross-sections showed that MDA is enriched in the intima, indicating endothelial cells (ECs) as a major target of MDA. My proposed stud- ies will uncover the mechanisms by which neutralizing MDA decreases atherosclerosis, with an emphasis on EC biology. As the innermost lining of blood vessels, normal ECs are critical for vascular homeostasis and functions. Under physiological conditions, intact ECs maintain an optimal balance between vessel integrity and permeability, exhibit anti-inflammatory function, and maintain normal vascular metabolism. My preliminary studies found that MDA induced excess heme accumulation in EC in vivo, and this was associated with induc- tion in EC of expression of genes encoding heme synthesis enzymes. Unlike its normal functions for oxygen transport and storage, electron transfer or drug metabolism, excess heme causes inflammation and EC dys- function, and increases vascular permeability. Based on my preliminary data, I hypothesize that MDA induces heme accumulation, which promotes endothelial dysfunction during atherogenesis. My proposal will as- sess the pathological effects of the MDA-heme axis on EC dysfunction during atherosclerosis. In Specific Aim1 (K99 phase), I will dissect roles of MDA in EC dysfunction and atherosclerosis using the IK17-scFvLdlr-/- mice. I will also systematically characterize the effects of MDA on EC transcriptome. In Specific Aim2 (R00 phase), I will characterize the effects of MDA on endothelial heme synthesis, and elucidate the underlying mechanisms. In specific Specific Aim3 (K99 and R00 phase), I will generate a new inducible endothelial cell-specific Alas1 (rate-limiting enzyme for heme synthesis) knockout mouse model to study the impact of excess heme on endo- thelial dysfunction and atherosclerosis. The roles of MDA-heme axis in EC dysfunction will be defined in vitro and in vivo. These studies will uncover mechanisms by which targeting MDA and heme can prevent EC dys- function and define novel therapeutic strategies to improve endothelial function and atherogenesis. The out- standing resources and stimulating research environment at UCSD will provide exemplary support for the ap- plicant’s goal of becoming a successful and independent investigator, and the candidate’s mentor has a suc- cessful track record of transitioning trainees into independent faculty. This K99/R00 award will support the ap- plicant toward a tenure track faculty position.

项目摘要/摘要丙二醛（MDA）是非酶脂质过氧化的普遍存在且高反应性的最终产物， MDA可以共价修改蛋白质，被认为是炎症和动脉粥样硬化。结果表明，血液MDA水平与冠心病相关。然而，它在动脉粥样硬化中的确切作用尚不清楚，因为没有体内策略来具体策略使它变形。我们最近生成了IK17-SCFV转基因小鼠，该小鼠表达单个链可变片段靶向MDA的人IK17抗体的（SCFV）。我的初步研究发现IK17-SCFV改善了西方饮食（WD）诱导了LDLR - / - 小鼠的动脉粥样硬化。病变横截面的MDA染色表明 MDA富含内膜，表明内皮细胞（EC）是MDA的主要靶标。我建议的螺柱 - IE将揭示中和MDA下降的机制，并强调 EC生物学。作为血管最内向的北壁，正常EC对于血管稳态至关重要功能。在物理条件下，完整的EC在船只完整性和渗透性，暴露的抗炎功能并保持正常的血管代谢。我的初步研究发现，MDA诱导体内EC中的血红素过量积累，这与诱导有关编码血红素合成酶的基因表达的EC。与氧气的正常功能不同运输和存储，电子转移或药物代谢超过血红素会引起感染和EC dys- 功能，并增加血管渗透性。根据我的初步数据，我假设MDA影响血红素积累，可在动脉粥样硬化期间促进内皮功能障碍。我的提议将为 SESS在动脉粥样硬化期间，MDA-轴轴对EC功能障碍的病理影响。在特定的AIM1中（K99期），我将使用IK17-SCFVLDLR - / - 小鼠剖析MDA在EC功能障碍和动脉粥样硬化中的作用。还将系统地表征MDA对EC转录组的影响。在特定的AIM2（R00阶段）中，我将表征MDA对内皮血红素合成的影响，并阐明潜在的机制。在特定的特定AIM3（K99和R00阶段）中，我将生成一个新的诱导内皮细胞特异性ALAS1 （血红素合成速率限制酶）基因敲除小鼠模型，以研究过量血红素对内质的影响三功能障碍和动脉粥样硬化。 MDA - 血清轴在EC功能障碍中的作用将在体外定义和体内。这些研究将发现靶向MDA和血红素可以防止EC dys的机制功能并定义新的治疗策略，以改善内皮功能和动脉粥样硬化。外 UCSD的常规资源和刺激研究环境将为AP提供示例性的支持 Plicant成为一名成功和独立的调查员的目标，候选人的导师很成功将学员过渡到独立教师的记录。该K99/R00奖将支持AP- 统治轨道教师的职位。