Targeting Resident Cardiac Fibroblast Subpopulations for Protection Against Fibrosis

针对常驻心脏成纤维细胞亚群以预防纤维化

• 批准号: 10544519
• 负责人: Taben M. Hale
• 金额: $ 59.62万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10544519
• 关键词: Affect; Aftercare; American; Angiotensin II; Area; Automobile Driving; Cardiac; Cause of Death; Cells; Cellular Assay; Chromatin; Chromatin Structure; Cicatrix; Data; Development; Ensure; Enzyme Inhibition; Epigenetic Process; Exhibits; Extracellular Matrix; Fibroblasts; Fibrosis; Future; Gene Expression; Genes; HDAC2 gene; Heart; Heart Diseases; Heart failure; Histone Deacetylase; Hypertension; In Vitro; Inbred SHR Rats; Infusion procedures; Knockout Mice; Laboratory Finding; Left; Left ventricular structure; Mediating; Memory; Methodology; Mission; Modification; Myofibroblast; National Heart, Lung, and Blood Institute; Patients; Peptidyl-Dipeptidase A; Phenotype; Physiological; Physiology; Play; Population; Prevention; Process; Production; Proliferating; Protein Isoforms; Proteins; Public Health; Rattus; Research; Resistance; Risk Factors; Role; Signal Transduction; Small Interfering RNA; Testing; Tissues; Transcript; Transposase; Validation; Ventricular; Work; blood pressure reduction; chromatin remodeling; coronary fibrosis; experimental study; fascinate; hypertensive; in vivo; injured; interdisciplinary approach; novel therapeutic intervention; osteopontin; pressure; prevent; programs; response; single-cell RNA sequencing; targeted treatment; tool

PROJECT SUMMARY/ABSTRACT Hypertension stimulates cardiac fibroblast (CF) expansion, activation, and excess extracellular matrix (ECM) production. Although there are no approved treatments for cardiac fibrosis, angiotensin converting enzyme inhibition (ACEi) limits CF activation and ECM accumulation. Recent findings from the laboratory of the PI demonstrate that resident CFs, once considered functionally homogeneous, consist of physiologically distinct populations that differentiate to diverse phenotypes in response to pressure overload. The premise for this application is based on these findings in which hypertensive rats were transiently treated with an ACEi prior to single cell RNA sequencing on resident CFs. Pre-treatment with ACEi shifts CF subpopulations to generate homeostatic CFs with a reduced capacity for fibrosis. This effect persists after treatment is stopped, indicating memory is retained. The proposed studies will reveal the mechanisms by which CF subpopulations shift to determine how to reprogram CFs to display a homeostatic, less fibrogenic phenotype. Following ACEi, homeostatic CFs comprise the largest subpopulation of resident CFs and are the least fibrogenic. Trajectory analysis revealed a gateway CF subpopulation that is the immediate precursor to activated CFs, and this gateway cluster was the most depleted by ACEi. Gateway CFs were defined by high expression of Spp1, encoding for the protein osteopontin, which induces several pro-fibrotic genes and represents a critical target candidate to maintain the activated CF pool. ACEi altered expression of epigenetic genes, indicating changes in chromatin structure may drive the persistent shift from gateway to homeostatic CF subpopulations. These compelling preliminary results led to the central hypothesis: transient reduction in angiotensin II signaling alters CF memory to protect against left ventricle (LV) fibrosis by fibroblast subpopulation-specific reprogramming of chromatin structure to shift an osteopontin-producing gateway subpopulation toward a homeostatic subpopulation with low fibrogenic capacity. To test the hypothesis, the following specific aims are proposed: Aim 1) elucidate the degree to which reduction in angiotensin II signaling mediates the persistent shift in resident CF physiology that protects from future fibrosis; Aim 2) determine the impact of chromatin structural modification on shifting the gateway cluster toward the homeostatic cluster; and Aim 3) ascertain the degree to which reduction in osteopontin mediates the shift to a less fibrogenic phenotype. In this application, the research team uses a multidisciplinary approach employing in vivo and in vitro methodologies to test the hypothesis. Successful completion of these experiments will determine whether reduction in angiotensin II signaling mediates the expansion of a subset of homeostatic CFs that renders the LV resistant to fibrosis. It is expected that the key drivers regulating the shift from a gateway to a homeostatic subpopulation of CFs will be identified. Impact: These anticipated findings will have a positive impact in developing CF-targeted therapies for the treatment and prevention of fibrotic remodeling that underlies heart disease.

项目摘要/摘要 高血压刺激心脏成纤维细胞（CF）膨胀，激活和过多的细胞外基质（ECM） 生产。尽管没有批准的心脏纤维化治疗方法，但血管紧张素转化酶 抑制（ACEI）限制了CF激活和ECM积累。 PI实验室的最新发现 证明曾经认为在功能均匀的居民CFS由生理上不同的 响应压力超负荷而与不同表型区分开的种群。这个前提 应用是基于这些发现，在这些发现中，高血压大鼠在暂时用ACEI治疗 居民CFS上的单细胞RNA测序。使用ACEI的预处理会改变CF亚群以生成 稳态CFS的纤维化能力降低。停止治疗后这种效果持续存在，表明 保留记忆。拟议的研究将揭示CF亚群转移到的机制 确定如何重新编程CFS显示体内稳态，纤维纤维较少的表型。跟随Acei， 稳态CFS是常驻CFS的最大亚群，是纤维纤维最低的。弹道 分析揭示了一个Gateway CF亚群，这是激活CFS的直接前体，这是 Gateway群集是ACEI耗尽的最多。网关CF是通过SPP1的高表达来定义的 编码蛋白质骨桥蛋白，该蛋白质骨桥蛋白诱导几个促纤维化基因并代表关键靶标 维护激活的CF池的候选人。 ACEI改变了表观遗传基因的表达，表明变化 在染色质结构中，可能会驱动从网关到体内稳态CF亚群的持续变化。这些 引人入胜的初步结果导致了中心假设：血管紧张素II信号的短暂降低改变 CF记忆可通过成纤维细胞亚群特异性重编程来防止左心室（LV）纤维化 染色质结构将产生骨桥的网关亚群转移到稳态 纤维化能力低的亚群。为了检验该假设，提出了以下具体目的： 目标1）阐明血管紧张素II信号传导介导的程度介导 可保护未来纤维化的居民CF生理学；目标2）确定染色质结构的影响 将网关群集转移到稳态群集时进行修改；目标3）确定学位 骨桥蛋白的减少介导了转移到纤维化表型较低的情况下。在此应用程序中 研究团队使用使用体内和体外方法的多学科方法来测试 假设。这些实验的成功完成将确定血管紧张素II的减少是否减少 信号传导介导了稳态CF的子集的扩展，从而使LV具有抗纤维化的能力。这是 预计监管从门户到CFS体内稳态亚群的关键驱动因素将是 确定。影响：这些预期的发现将对开发针对CF的疗法产生积极影响 基于心脏病的纤维化重塑的治疗和预防。