Serotonin Signaling in Mitral Valve Homeostasis, Maintenance and Restoration

二尖瓣稳态、维护和恢复中的血清素信号传导

• 批准号: 10361455
• 负责人: Giovanni Ferrari
• 金额: $ 73.12万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10361455
• 关键词: Adult; Affect; Age; Agonist; Alpha Granule; Anabolism; Antidepressive Agents; Area; Aspirin; BMP4; Blood; Blood Platelets; Bone Marrow; Bone Marrow Ablation; Bone Marrow Transplantation; CD34 gene; Canis familiaris; Carcinoid Tumor; Cells; Childhood; Chronic; Clinical Pathology; Cytoplasmic Granules; Diet; Disease; Disease Progression; Down-Regulation; Endothelial Cells; Endothelium; Event; Experimental Designs; Exposure to; Extracellular Matrix; Extracellular Matrix Proteins; Feasibility Studies; Flow Cytometry; Functional disorder; Gene Expression Profile; HTR2A gene; Heart Valve Diseases; Heart Valves; Homeostasis; Homing; Human; In Vitro; Maintenance; Measurement; Mediating; Mesenchymal; Mitral Valve; Mitral Valve Insufficiency; Mitral Valve Prolapse; Modeling; Multivariate Analysis; Mus; Neurotransmitters; Operative Surgical Procedures; Pathogenesis; Pathologic; Patients; Pharmaceutical Preparations; Phenotype; Platelet Activation; Population; Preventive treatment; Production; Proteomics; Protocols documentation; Quantitative Reverse Transcriptase PCR; Receptor Signaling; Research; Role; Serotonin; Signal Transduction; Specimen; Therapeutic; Thick; Tissues; Tryptophan; Tryptophan 5-monooxygenase; United States National Institutes of Health; Up-Regulation; antagonist; aortic valve; base; coronary fibrosis; disorder control; experimental study; human subject; inhibitor; interstitial cell; migration; personalized approach; progenitor; programs; receptor; repaired; restoration; reuptake; serotonin receptor; serotonin transporter; single cell sequencing; stem cells; therapeutic target; transcriptome; transcriptomics

Degenerative mitral regurgitation (MR) due to myxomatous valve disease affects millions. The only treatment is either valve repair or replacement. This competing renewal will advance understanding of the role of the neurotransmitter, serotonin (5HT) in MR. Heart valve disease has been associated with both 5HT-secreting carcinoid tumors and medications, such as the diet drug, Dexfenfluoramine. Based on our progress in the 1ST program period, we will investigate the hypothesis that 5HT-mechanisms involving the serotonin transporter (SERT), and 5HT receptor (HTR) signaling, both in platelets and mitral valve interstitial cells (MVIC) of bone marrow origin, contribute to the pathophysiology MR, and represent promising therapeutic targets. Specific Aim 1: To dissect 5HT-mediated mechanisms that influence pathologic remodeling of MV leaflets in human subjects and mice Subaim 1A: To characterize 5HT-mediated MV remodeling in MR compared to normal mitral valve (MV) leaflets and human-derived MVICs. SERT-antagonists, and HTR inhibitor studies will dissect unique 5HT related transcriptome and cellular phenotypes associated with MR progression in vitro and ex vivo under TGFb, BMP4, and 5HT stimulation. Endpoints will be transcriptomic, extracellular matrix (ECM) remodeling in human MVIC and tissue from MR compared to normal leaflets exposed to 5HT-related mechanistic interrogation. Subaim 1B: To investigate the role of SERT in the pathogenesis of MR: The SERT deleted mouse (SERT-/-) spontaneously develops a valvulopathy affecting the mitral and aortic valves. Mechanistic studies will compare SERT-/- to SERT+/+ . Endpoints will include valve thickness, myocardial fibrosis, and changes in the MV transcriptome, to understand disease progression in this SERT-related valvulopathy. Specific Aim 2: To investigate the role of 5HT in the pathogenesis of MR involving platelet mechanisms and bone marrow derived blood outgrowth endothelial cells (BOEC) that express both CD34 and HTR2B. Subaim 2A: It is noteworthy that MR results in a chronic state of platelet activation, since platelets are the primary carriers of 5HT in blood, releasing 5HT upon activation. We will study the role of platelets in 5HT related MR pathophysiology in human subjects, canines with MR, and mice. Endpoints will include 5HT levels, platelet activation markers, and differences in TGF-b1 levels resulting from platelet alpha granule release. Subaim 2B: To investigate the role of bone marrow derived cells in the pathophysiology of 5HT mechanisms that affect MR. BOEC will be cultivated from the study groups in Subaim 2A. The experimental designs will use flow cytometry for cell characterization, qRT-PCR studies to assess gene expression patterns, and proteomic approaches to assess HTR activity, and measurements of ECM production in vitro. It is expected that the mechanistic results of these studies will lead to therapeutic directions for MR that target platelet derived 5HT and leverage a personalized approach using BOEC to model the pathophysiology.

粘液瘤性瓣膜疾病引起的退行性二尖瓣反流 (MR) 影响着数百万人。唯一的治疗方法是修复或更换瓣膜。这种竞争性更新将促进对神经递质、血清素 (5HT) 在 MR 中的作用的理解。心脏瓣膜疾病与分泌 5HT 的类癌瘤和药物（例如减肥药右芬氟明）有关。基于我们在第一个项目期间的进展，我们将研究以下假设：涉及骨髓来源的血小板和二尖瓣间质细胞（MVIC）中的血清素转运蛋白（SERT）和5HT受体（HTR）信号传导的5HT机制有助于病理生理学MR，并代表有希望的治疗靶点。具体目标 1：剖析 5HT 介导的影响人类受试者和小鼠 MV 小叶病理重塑的机制 Subaim 1A：与正常二尖瓣 (MV) 小叶和人源 MVIC 相比，表征 MR 中 5HT 介导的 MV 重塑。 SERT 拮抗剂和 HTR 抑制剂研究将剖析与 TGFb、BMP4 和 5HT 刺激下的体外和离体 MR 进展相关的独特 5HT 相关转录组和细胞表型。终点将是与暴露于 5HT 相关机制询问的正常小叶相比，人类 MVIC 和 MR 组织中的转录组学、细胞外基质 (ECM) 重塑。 Subaim 1B：研究 SERT 在 MR 发病机制中的作用：SERT 缺失小鼠 (SERT-/-) 自发发生影响二尖瓣和主动脉瓣的瓣膜病。机制研究将比较 SERT-/- 与 SERT+/+ 。终点将包括瓣膜厚度、心肌纤维化和 MV 转录组的变化，以了解这种 SERT 相关瓣膜病的疾病进展。具体目标 2：研究 5HT 在 MR 发病机制中的作用，涉及血小板机制和同时表达 CD34 和 HTR2B 的骨髓来源的血液生长内皮细胞 (BOEC)。 Subaim 2A：值得注意的是，MR会导致血小板活化的慢性状态，因为血小板是血液中5HT的主要载体，在活化时释放5HT。我们将在人类受试者、患有 MR 的犬类和小鼠中研究血小板在 5HT 相关 MR 病理生理学中的作用。终点将包括 5HT 水平、血小板活化标记物以及血小板 α 颗粒释放导致的 TGF-b1 水平差异。 Subaim 2B：研究骨髓来源细胞在影响 MR 的 5HT 机制的病理生理学中的作用。 BOEC将从Subaim 2A的研究组中培养。实验设计将使用流式细胞术进行细胞表征，使用 qRT-PCR 研究来评估基因表达模式，使用蛋白质组学方法来评估 HTR 活性，并测量体外 ECM 的产生。预计这些研究的机制结果将引导针对血小板衍生 5HT 的 MR 治疗方向，并利用 BOEC 的个性化方法来模拟病理生理学。