Role of Inhibitory SMADs in Calcific Aortic Valve Disease

抑制性 SMAD 在钙化主动脉瓣疾病中的作用

基本信息

批准号：
8891481
负责人：
Linda L. Demer
金额：
$ 37.92万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-08-23 至 2017-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8891481
关键词：
3-Dimensional Adenine Alkaline Phosphatase Animals Aortic Valve Stenosis Biological Biological Assay Blood Vessels Calcified Cardiac Cartilage Cells Collagen Collagen Type X Congestive Heart Failure Cyclic AMP-Dependent Protein Kinases Development Diet Dietary Fats Disease Early Diagnosis Early treatment Embryo Embryonic Development Fatty acid glycerol esters Feedback Fluorochrome Gel Gene Silencing Homeostasis Human Hyperlipidemia Image In Vitro Inflammation Inflammatory Inflammatory Bowel Diseases Knowledge Lead Lesion Link MADH6 gene MADH7 gene Measures Mediating Mediator of activation protein Medical Modality Molecular Molecular Target Morbidity - disease rate Mothers Mus Myocardial perfusion Nodule Organ Culture Techniques Osteocalcin Outcome Oxygen Pathway interactions Patients Perfusion Play Preventive Process Public Health Resistance Role Scleroderma Severities Signal Transduction Signaling Molecule Smooth Muscle Myocytes Symptoms Syncope TNF gene Testing Therapeutic Therapeutic Intervention Time Tissues Transforming Growth Factors Tumor Necrosis Factor-alpha Up-Regulation Ventricular Arrhythmia Work aortic valve aortic valve disorder base bone morphogenetic protein 2 calcification cartilage cell cell type coronary fibrosis cytokine feeding in vivo interstitial cell member mortality novel oxidant stress oxidized lipid receptor response tumorigenesis valve replacement ventricular hypertrophy

项目摘要

DESCRIPTION (provided by applicant): Role of Inhibitory SMADs in Calcific Aortic Valve Disease Calcific aortic valve disease (CAVD) is associated epidemiologically with hyperlipidemia, the biological effects of which appear to occur through an inflammatory, positive feedback loop linking oxidized lipids, cytokines, and oxidant stress. Although it is a rapidly fatal disorder, therapeutic options are extremely limited. Its cliical severity is due to leaflet stiffening, which restricts valve opening, increasing outflow resistance and oxygen demand, while impairing cardiac perfusion and oxygen supply. Thus, a better understanding of the mechanisms underlying calcification and stiffening is critical for the development of early diagnosis and medical therapy. CAVD is increasingly acknowledged as a regulated process, involving osteochondrogenic differentiation of valvular cells. Evidence now suggests that the downstream targets of members of the transforming growth factor-ß (TGF-ß) superfamily, known as "inhibitory small mothers against decapentaplegic" (I-SMADs; SMAD6 and 7), regulate valve embryogenesis and may serve as a mitigating factor in CAVD. Their upstream effectors, BMP-2 and TGF-ß, are expressed in CAVD, and both induce valvular cell calcification. They signal through receptor-associated SMADs (R-SMADs) to induce osteochondrogenic factors. Although I-SMADs were originally identified as negative regulators, under some conditions, they have been shown to promote TGF-ß superfamily signaling. In addition, BMP-2 and TGF-ß may also promote leaflet stiffening, given their ability to induce aggregation and contraction of valvular interstitial cells into nodules resembling those on leaflet in CAVD. In preliminary studies, we found that 1) I-SMAD expression is upregulated in aortic valves in hyperlipidemic mice, 2) TNF- induces I-SMAD expression in aortic smooth muscle cells, and 3) protein kinase A (PKA) activation induces I-SMAD expression and inhibits cellular nodule formation in vitro. We hypothesize that I-SMADs are induced by pro-inflammatory factors and that they mitigate CAVD by negatively regulating TGF-ß superfamily-induced CAVD. To test this novel hypothesis, we propose three Specific Aims. In Aim 1, we will establish the mechanism of effects of pro-inflammatory factors on I-SMAD induction in CAVD. We will use in vitro (murine valvular interstitial cells; mVIC), ex vivo (murine valvular organ culture; mVOC) and in vivo (PontgLdlr-/-Apob100 and p75Tnfr-/-Ldlr-/-Apob100 mice) approaches. In Aim 2, we will test whether I-SMADs regulate CAVD in response to pro-inflammatory factors. We will employ in vitro, ex vivo, and in vivo approaches using Smad6-/- mice and their I-SMAD-deficient mVIC and mVOC. Oxidant stress and inflammation will be induced by oxidized lipids and TNF- in vitro and by an adenine diet in vivo. In Aim 3, we will test whether I-SMADs mediate inhibitory effects of PKA on formation and contraction of valvular nodules. We will use collagen-gel contraction and nodule formation assays with I- SMAD gene silencing. Results of the proposed work will harness the regulatory power of I-SMADs for development of preventive measures and medical treatments for CAVD.

描述（由申请人提供）：抑制性SMAD在钙化瓣膜钙化瓣膜疾病（CAVD）中的作用是与Hyperlipi Demia相邻的，但其生物学作用似乎发生炎症，阳性反馈环将脂质联系起来，尽管它是一种快速致命的致命疾病。治疗选择非常有限氧气的需求损害了心脏灌注和氧气疗法，这是对瓣膜诊断和某些医疗疗法的批判性。 Cavd中的缓解因素最初被认为是负调节剂，已被证明可以在BMP-2和TGF-2和TGF-β上促进TGF-ß，鉴于它们能够诱导瓣膜间质细胞的聚集和收缩的能力，也可能会促进Leafflet僵硬。在体外，通过调节TGF-ß超家族诱导的CAVD来测试这种新的假设，在体外，它们会在体外减轻CAVD。 MVIC），Ex Vivo（鼠瓣膜器官培养； MVOC）和体内（Pontgldlr-/ - APOB100和P75TNFR - / - LDLR - / - APOB100小鼠。测试I-SMADS是否调节CAVD以响应cavd，以响应cavd we Pro摄影因素。我们。将在体外使用SMAD6-/氧化剂应力和炎症的体外使用，并通过氧化的脂质和TNF-IN VIVO诱导，并通过AIM 3中的腺嘌呤饮食诱导。 PKA对形成和瓣膜的抑制作用，我们将使用胶原蛋白凝胶收缩和结节形成测定法检测测定SMAD基因沉默的结果。对于cavd。