Proteoglycan Regulation During Cardiac Valve Development and Homeostasis

心脏瓣膜发育和稳态过程中的蛋白多糖调节

基本信息

批准号：
8760823
负责人：
Christine Bruins Kern
金额：
$ 37.38万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-01 至 2018-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8760823
关键词：
ADAMTS Address Adult Affect Alleles American Architecture Area Bicuspid Biological Availability Cell Culture Techniques Cell Differentiation process Cell Lineage Cells Cleaved cell Clinical Trials Collagen Confocal Microscopy Data Defect Degenerative polyarthritis Development Diagnostic Disease Equilibrium Etiology Exhibits Extracellular Matrix Functional disorder Future Gene Mutation Genes Goals Heart Valve Diseases Heart Valves Histopathology Homeostasis Investigation Laboratories Lead Ligands Lung Maintenance Mediating Mesenchymal Metalloproteases Mitral Valve Modeling Morphology Mus Myocardial Nodule Operative Surgical Procedures Penetrance Peptide Hydrolases Peptides Pharmacologic Substance Pharmacological Treatment Phenotype Phosphorylation Plant Roots Play Population Predisposing Factor Pregnancy Proteoglycan Publishing Pulmonary valve structure Regulation Research Research Personnel Risk Factors Role Sclerosis Signal Transduction Smooth Muscle Actin Staining Method Stratification Tamoxifen Testing Therapeutic Time Tissues Transforming Growth Factor beta aged aortic valve aortic valve disorder base bicuspid aortic valve cell behavior clinically relevant cost feeding filamin in vivo inhibitor/antagonist malformation mouse model novel periostin postnatal public health relevance research study response semilunar valve spatiotemporal valvular insufficiency versican

ADAMTS Address Adult Affect Alleles American Architecture Area Bicuspid Biological Availability Cell Culture Techniques Cell Differentiation process Cell Lineage Cells Cleaved cell Clinical Trials Collagen Confocal Microscopy Data Defect Degenerative polyarthritis Development Diagnostic Disease Equilibrium Etiology Exhibits Extracellular Matrix Functional disorder Future Gene Mutation Genes Goals Heart Valve Diseases Heart Valves Histopathology Homeostasis Investigation Laboratories Lead Ligands Lung Maintenance Mediating Mesenchymal Metalloproteases Mitral Valve Modeling Morphology Mus Myocardial Nodule Operative Surgical Procedures Penetrance Peptide Hydrolases Peptides Pharmacologic Substance Pharmacological Treatment Phenotype Phosphorylation Plant Roots Play Population Predisposing Factor Pregnancy Proteoglycan Publishing Pulmonary valve structure Regulation Research Research Personnel Risk Factors Role Sclerosis Signal Transduction Smooth Muscle Actin Staining Method Stratification Tamoxifen Testing Therapeutic Time Tissues Transforming Growth Factor beta aged aortic valve aortic valve disorder base bicuspid aortic valve cell behavior clinically relevant cost feeding filamin in vivo inhibitor/antagonist malformation mouse model novel periostin postnatal public health relevance research study response semilunar valve spatiotemporal valvular insufficiency versican

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项目摘要

DESCRIPTION (provided by applicant): Adult cardiac valve disease affects up to 5% of Americans with approximately 25% of the aged population developing aortic valve sclerosis, a marker of valve disease. The primary treatment of valvular insufficiency is surgical intervention with an estimated cost of $1 billion per year in the US. The fact that most diseased valves have an underlying malformation suggests that determining the etiology of valve diseases lies in the discovery of novel mechanisms and genes that are involved in valve development. However, progress in discovering the roots of valve disease has been limited in part due to the lack of viable mouse models that exhibit significant penetrance of a cardiac valve phenotype. A hallmark of both developmental myxomatous valve abnormalities and adult disease is the loss of stratification of extracellular matrix (ECM) and the accumulation of the ECM proteoglycans including versican. The ADAMTS (ADisintegrin-like And Metalloprotease domain with ThromboSpondin-type 1 motifs) proteoglycanases are a specific class of extracellular matrix metalloproteases that cleave proteoglycans. Mice deficient in ADAMTS5 develop severely enlarged cardiac valves by late gestation with significant accumulation of versican, the ECM substrate of ADAMTS5. In vivo reduction of versican, rescues the Adamts5-/- valve phenotype, and demonstrates that cleavage of versican is required for its clearance from the provisional ECM. To date, versican is the only ECM substrate of ADAMTS5 known to accumulate in ADAMTS5 deficient valves. Prevalvular mesenchymal cells from the Adamts5-/- mice maintain Sox9 expression and show elevated levels of proliferation suggesting they do not differentiate like their WT counterparts. Our published data also show that ECM accumulation of versican inhibits Smad2 phosphorylation. Intergenetic cross of the Adamts5-/- with Smad2-/- exacerbates the valve phenotype and results in a high penetrance (80%) of bicuspid aortic and pulmonary valves. In this application we seek to elucidate ECM-cell signaling mechanisms that are activated in response to proteoglycan cleavage and integral to the valve maturation and homeostasis. Since ADAMTS5 peptide inhibitors are in clinical trials to alleviate osteoarthritis, investigation into the requirement of proteoglycan cleavage in normal valve development and homeostasis has immediate clinical relevance. The three specific aims of our application test our overarching hypothesis that ADAMTS5 mediated versican cleavage plays a pivotal role in semilunar cardiac valve maturation through interconnections with TGFbeta signaling that control cell differentiation and the balance of proteoglycan-rich and fibrous ECM. Aim 1: Determine the mechanism by which ADAMTS5 dependent ECM remodeling upregulates Smad2 phosphorylation during semilunar valve development. Aim 2: Determine the spatiotemporal expression of ADAMTS5 that is required to remodel the provisional ECM of endocardial cushions during semilunar valve development. Aim 3: Determine the consequence of ADAMTS5 deficiency on adult murine valve ECM and function.

描述（由申请人提供）：成人心脏瓣膜疾病最多影响5％的美国人，大约25％的年龄人群发生了主动脉瓣硬化症，这是瓣膜疾病的标志。瓣膜功能不全的主要治疗方法是外科干预，在美国估计每年成本10亿美元。大多数患病的瓣膜具有潜在的畸形，这一事实表明，确定瓣膜疾病的病因在于发现与瓣膜发育有关的新机制和基因的发现。但是，发现瓣膜疾病根部的进展受到限制，部分原因是缺乏可行的小鼠模型，这些模型表现出心脏瓣膜表型的显着渗透性。发育性菌丝瓣异常和成人疾病的标志是细胞外基质（ECM）的分层丧失以及包括versican在内的ECM蛋白聚糖的积累。 ADAMTS（具有血小板蛋白型1基序的Adisintegrin样和金属蛋白酶结构域）蛋白聚糖是一类特定的细胞外基质基质金属蛋白酶，可裂解蛋白聚糖。缺乏ADAMTS5的小鼠通过妊娠晚期出现严重肿大的心脏瓣膜，并大量积累了Adamts5的ECM底物。在体内减少Versican，营救Adamts5 - / - 瓣膜表型，并证明versican的切割是从临时ECM中清除所必需的。迄今为止，Versican是已知在ADAMTS5缺陷阀中积累的ADAMTS5的ECM底物。来自ADAMTS5 - / - 小鼠的患者间充质细胞保持SOX9的表达，并显示出升高的增殖水平，表明它们没有像WT对应物那样区分。我们已发布的数据还表明，versican的ECM积累抑制了SMAD2磷酸化。 ADAMTS5 - / - 与Smad2 - / - 的遗传交叉加剧了瓣膜表型，并导致双刺主动脉和肺瓣的高渗透率（80％）。在此应用中，我们试图阐明响应于蛋白聚糖的裂解和阀成熟和稳态不可或缺的ECM信号传导机制。由于ADAMTS5肽抑制剂正在接受临床试验以减轻骨关节炎，因此对正常瓣膜发育中蛋白聚糖切割的需求进行了调查，并且体内稳态具有直接的临床相关性。我们应用程序的三个具体目的测试了我们的总体假设，即ADAMTS5介导的versican裂解通过与TGFBETA信号的互连控制细胞分化以及Proteooglycan-富含蛋白粉和纤维性ECM的平衡，在半道路心脏瓣膜成熟中起关键作用。 AIM 1：确定ADAMTS5依赖ECM重塑的机制会在半道路阀发育过程中上调SMAD2磷酸化。 AIM 2：确定ADAMTS5的时空表达，这是在半隆瓣发育过程中重塑心内膜垫的临时ECM所需的。目标3：确定ADAMTS5缺乏对成年鼠瓣ECM和功能的后果。