Atherosclerosis Mechanisms: Angiotensin II production and action

动脉粥样硬化机制：血管紧张素 II 的产生和作用

基本信息

批准号：
10132375
负责人：
Alan Daugherty
金额：
$ 48.69万
依托单位：
UNIVERSITY OF KENTUCKY
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-05-01 至 2023-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10132375
关键词：
Address Amino Acid Sequence Androgens Angiotensin II Angiotensin Type 1a Receptor Angiotensinogen Arterial Fatty Streak Atherosclerosis Binding Breeding Cell Culture System Cleaved cell Color Conserved Sequence Data Development Elements Endocrine system Endothelial Cells Enzymes Fibroblasts Genes Hepatocyte Human In Vitro Infusion procedures Kidney LDL-Receptor Related Protein 2 Lesion Leukocytes Literature Location Low Density Lipoprotein Receptor LoxP-flanked allele Mediating Methods Mus Mutagenesis Nephrons Pathway interactions Peptidyl-Dipeptidase A Pharmacology Play Production Proteins Renin Renin-Angiotensin System Reproducibility Role Site Smooth Muscle Myocytes Source Surface Plasmon Resonance System Techniques Testing Therapeutic Transgenes Transgenic Mice Viral base cell type enzyme deficiency experimental study hypercholesterolemia insight member mouse model mutant novel therapeutic intervention prevent promoter protein structure receptor urinary

项目摘要

Abstract The renin angiotensin system (RAS) plays a critical role in the development of atherosclerosis. Mechanisms by which the RAS contributes to atherosclerosis have been focusing on effects of angiotensin II (AngII) production and its action through AT1a receptors within atherosclerotic lesions. On the basis of our preliminary data, we challenge this concept and propose a new hypothesis: Renal AngII production through a megalin-mediated pathway in proximal convoluted tubules (PCTs) promotes atherosclerosis via its local stimulation of AT1a receptors. Angiotensinogen (AGT), the substrate of the RAS, derived from hepatocytes is filtered through glomeruli and retained by megalin, a member of LDL receptor superfamily, in PCTs. Our protein sequence and structure analyses identified two conserved sequences that may associate with its binding to megalin. Aim 1 will define how hepatocyte-derived AGT regulates renal AngII production and contributes to atherosclerosis. We will use site-mutagenesis, surface plasmon resonance, and cell culture system to determine how AGT and megalin interact in vitro. Subsequently, we will use an adeno-associated viral (AAV) system to manipulate conserved sequences of AGT in hepatocyte-specific AGT deficient mice to determine whether conserved sequences of AGT influence renal AngII production and atherosclerosis. Effects of megalin on renal AngII production and atherosclerosis will be determined using PCT-specific megalin deficient mice. Since AGT is cleaved by two critical enzymes, renin and angiotensin-converting enzyme (ACE), to produce AngII, Aim 2 will first determine whether renin or ACE derived from PCTs contributes to renal AngII production and atherosclerosis using PCT-specific renin and ACE deficient mice, respectively. Studies proposed in Aim 1 for AGT and megalin interaction and Aim 2 for the two enzymes (renin and ACE) do not provide direct evidence whether AngII produced in PCTs contributes to atherosclerosis. To answer this question, we will use a transgenic mouse model that has restricted production of AngII in PCTs. AngII promotes atherosclerosis through AT1a receptor- mediated mechanism. Therefore, subsequent experiments will determine whether PCTs are the location for AT1a receptors to promote atherosclerosis. Completion of proposed studies will provide evidence whether renal PCTs are the major source for each classic RAS component to promote atherosclerosis. Demonstration of this new concept may change our understanding of the AngII/AT1a receptor-mediated mechanisms of atherosclerosis, which may also provide insights into developing new therapeutic strategies.

抽象的肾素血管紧张素系统（RAS）在肾素血管紧张素系统（RAS）的发展中起着至关重要的作用动脉粥样硬化。 RAS 导致动脉粥样硬化的机制已被阐明重点关注血管紧张素 II (AngII) 产生的影响及其通过 AT1a 受体的作用动脉粥样硬化病变内。根据我们的初步数据，我们挑战这个概念并提出一个新的假设：肾 AngII 的产生是通过巨蛋白介导的近曲小管（PCT）中的通路通过其局部促进动脉粥样硬化 AT1a 受体的刺激。血管紧张素原 (AGT)，RAS 的底物，源自来自肝细胞的物质通过肾小球过滤并被 LDL 的成员巨蛋白保留受体超家族，在 PCT 中。我们的蛋白质序列和结构分析确定了两个可能与其与巨蛋白结合相关的保守序列。目标 1 将定义如何肝细胞来源的 AGT 调节肾脏 AngII 的产生并导致动脉粥样硬化。我们将使用位点诱变、表面等离子共振和细胞培养系统来确定 AGT 和巨蛋白如何在体外相互作用。随后，我们将使用腺相关病毒 (AAV) 系统在肝细胞特异性 AGT 缺陷中操纵 AGT 保守序列小鼠以确定 AGT 的保守序列是否影响肾脏 AngII 的产生和动脉粥样硬化。巨蛋白对肾脏 AngII 产生和动脉粥样硬化的影响使用 PCT 特异性巨蛋白缺陷小鼠测定。由于 AGT 被两个关键的酶、肾素和血管紧张素转换酶 (ACE)，以产生 AngII，目标 2 将首先确定 PCT 衍生的肾素或 ACE 是否有助于肾脏 AngII 的产生，以及分别使用 PCT 特异性肾素和 ACE 缺陷小鼠进行动脉粥样硬化研究。研究目标 1 中提出了 AGT 和巨蛋白相互作用，目标 2 中提出了两种酶（肾素和巨蛋白） ACE）没有提供 PCT 中产生的 AngII 是否有助于动脉粥样硬化。为了回答这个问题，我们将使用转基因小鼠模型，该模型具有 PCT 中 AngII 的生产受到限制。 AngII通过AT1a受体促进动脉粥样硬化介导机制。因此，后续实验将确定PCT是否是 AT1a 受体促进动脉粥样硬化的位置。完成拟议的研究将提供证据证明肾脏 PCT 是否是每个经典 RAS 成分的主要来源促进动脉粥样硬化。这个新概念的展示可能会改变我们的理解 AngII/AT1a 受体介导的动脉粥样硬化机制，这也可能提供开发新治疗策略的见解。

项目成果

期刊论文数量（9）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

A mini-review on quantification of atherosclerosis in hypercholesterolemic mice.

DOI：
10.36922/gtm.v1i1.76
发表时间：
2022-01-01
期刊：
Global translational medicine
影响因子：
0
作者：
Chen, Hui;Howatt, Deborah A;Lu, Hong S
通讯作者：
Lu, Hong S

Links lipoproteins to chronic kidney disease and atherosclerosis.

DOI：
10.1097/mol.0000000000000625
发表时间：
2019-10
期刊：
Current Opinion in Lipidology
影响因子：
4.4
作者：
Hong S. Lu;M. Kukida;A. Daugherty
通讯作者：
Hong S. Lu;M. Kukida;A. Daugherty

Editorial: Cardiovascular Fibrosis and Related Diseases: Basic and Clinical Research Advances.

DOI：
10.3389/fcvm.2022.879780
发表时间：
2022
期刊：
Frontiers in cardiovascular medicine
影响因子：
3.6
作者：
Bei Y;Lu HS;Zhong J
通讯作者：
Zhong J

Manipulation of components of the renin angiotensin system in renal proximal tubules fails to alter atherosclerosis in hypercholesterolemic mice.

DOI：
10.3389/fcvm.2023.1250234
发表时间：
2023
期刊：
FRONTIERS IN CARDIOVASCULAR MEDICINE
影响因子：
3.6
作者：
Kukida, Masayoshi;Amioka, Naofumi;Ye, Dien;Chen, Hui;Moorleghen, Jessica J.;Liang, Ching-Ling;Howatt, Deborah A.;Katsumata, Yuriko;Yanagita, Motoko;Sawada, Hisashi;Daugherty, Alan;Lu, Hong S.
通讯作者：
Lu, Hong S.

Reporting Sex and Sex Differences in Preclinical Studies.