Epigenetic reprogramming of cardiac myofibroblasts for cardiac repair

心肌成纤维细胞的表观遗传重编程用于心脏修复

• 批准号: 10713647
• 负责人: YAO LIANG TANG
• 金额: $ 50.9万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10713647
• 关键词: ATAC-seq; Ablation; Adult; Cardiac; Cardiovascular system; Cells; Clinical; Data; Enhancers; Enzymes; Epigenetic Process; Fibroblasts; Fibrosis; Follicular Lymphoma; GATA4 gene; Gene Deletion; Gene Expression; Genes; Genetic Transcription; Goals; Heart; Heart failure; Homologous Gene; In Vitro; Knockout Mice; Knowledge; Mediating; Mus; Myocardial Infarction; Myocardial Ischemia; Myofibroblast; Natural regeneration; Nucleic Acid Regulatory Sequences; Pathologic; Pathway interactions; Phenotype; Population; Process; Proliferating; Pump; Recombinant adeno-associated virus (rAAV); Repression; Role; Running; Testing; Therapeutic; angiogenesis; cardiac angiogenesis; cardiac regeneration; cardiac repair; cell transformation; chromatin remodeling; coronary fibrosis; epigenomics; gene repression; heart function; improved; inhibitor; innovation; insight; ischemic injury; mouse model; novel; novel strategies; paracrine; progenitor; programs; regenerative; repaired; response; restraint; single-cell RNA sequencing; stem cells; transcription factor; transcriptome sequencing; transcriptomics; vector; ATAC-seq; Ablation; Adult; Cardiac; Cardiovascular system; Cells; Clinical; Data; Enhancers; Enzymes; Epigenetic Process; Fibroblasts; Fibrosis; Follicular Lymphoma; GATA4 gene; Gene Deletion; Gene Expression; Genes; Genetic Transcription; Goals; Heart; Heart failure; Homologous Gene; In Vitro; Knockout Mice; Knowledge; Mediating; Mus; Myocardial Infarction; Myocardial Ischemia; Myofibroblast; Natural regeneration; Nucleic Acid Regulatory Sequences; Pathologic; Pathway interactions; Phenotype; Population; Process; Proliferating; Pump; Recombinant adeno-associated virus (rAAV); Repression; Role; Running; Testing; Therapeutic; angiogenesis; cardiac angiogenesis; cardiac regeneration; cardiac repair; cell transformation; chromatin remodeling; coronary fibrosis; epigenomics; gene repression; heart function; improved; inhibitor; innovation; insight; ischemic injury; mouse model; novel; novel strategies; paracrine; progenitor; programs; regenerative; repaired; response; restraint; single-cell RNA sequencing; stem cells; transcription factor; transcriptome sequencing; transcriptomics; vector

PROJECT SUMMARY Heart failure is associated with activation of cardiac fibroblasts (Fib), which promotes cardiac fibrosis and pathological cardiac remodeling. Employing single-cell RNA-sequencing (scRNA-seq) in adult mouse hearts, we discovered that Enhancer of Zeste homolog 2 (EZH2), the major enzyme known to catalyze the transcriptional repression mark H3K27me3, is highly expressed in a specific POSTN+ Fib subpopulation (myofibroblasts, MFib). Of note, little is known about the functional role of EZH2 in regulating cardiac MFib, which is a critical knowledge gap given their epigenetic variability and pathological role. We demonstrate that although these MFib express GATA4, an early cardiac transcription factor, they fail to express the cardiovascular progenitor (CPC) gene programs, such as NKX2.5. Importantly, deletion of EZH2 inhibited MFib proliferation and switched on cardiovascular progenitor cell (CPC) gene programs. Moreover, deletion of EZH2 increased the pro-angiogenic paracrine effects of MFib and improved cardiac function post myocardial infarction (MI) These beneficial effects on cardiac function were lost in mice administered a novel rAAV-FLEX-DTA vector, which ablates MFib lacking EZH2, confirming the important functional role of this cell population. These findings suggest that EZH2 is a restraint on the transition of MFib to beneficial phenotypes and that inhibition of EZH2 provides a unique therapeutic approach to diminishing MFib proliferation while activating repair mechanisms. The overall goal of this project is to test the central hypothesis that EZH2 inhibition in myofibroblasts can transform the cell fate from pro-fibrotic myofibroblasts into pro-angiogenic CPC, thus attenuating fibrosis, improving cardiac angiogenesis, and boosting cardiac repair in the ischemic myocardium. This proposed project is innovative because it will generate unique mechanistic insights from novel approaches to cardiac regeneration by transforming cardiac myofibroblasts from a proliferative and pro-fibrotic phenotype to a pro-angiogenic and pro- regenerative phenotype. Our focus on EZH2-mediated chromatin remodeling in epigenetic repression of GATA4-mediated CPC program is translationally significant, as EZH2 inhibitors are available clinically and have recently been approved for the treatment of follicular lymphoma. Our preliminary findings highlight the potential for this pathway to be the focus of novel strategies for mitigating cardiac fibrosis and promoting cardiac angiogenesis after ischemic injury.

项目摘要 心力衰竭与促进心脏纤维化和心脏成纤维细胞的激活有关 病理心脏重塑。在成年小鼠心脏中采用单细胞RNA-sequencing（SCRNA-SEQ），我们 发现Zeste同源物2（EZH2）的增强子，已知的主要酶是催化转录的 抑制标记H3K27me3，在特定的后+ FIB亚群中高度表达（肌纤维细胞，MFIB）。 值得注意的是，关于EZH2在调节心脏MFIB中的功能作用知之甚少，这是一个关键的知识 差距鉴于其表观遗传变异性和病理作用。我们证明，尽管这些MFIB表示 GATA4，一种早期的心脏转录因子，无法表达心血管祖细胞（CPC）基因 程序，例如NKX2.5。重要的是，EZH2的缺失抑制了MFIB的增殖并打开 心血管祖细胞（CPC）基因程序。此外，EZH2的缺失增加了促血管生成 MFIB的旁分泌作用和改善心肌梗死后心脏功能（MI）这些有益作用 在给管理的小鼠中丢失了关于一种新型Raav-flex-DTA矢量的小鼠，消融MFIB缺乏 EZH2，确认了该细胞群的重要功能作用。这些发现表明EZH2是 限制MFIB向有益表型的过渡和抑制EZH2提供了独特的 在激活修复机制时减少MFIB增殖的治疗方法。总体目标 该项目是为了检验中心假设，即肌纤维细胞中的EZH2抑制可以改变细胞命运 从促纤维化的肌纤维细胞到促血管生成CPC，从而减弱纤维化，改善心脏 血管生成，并增加缺血性心肌的心脏修复。这个拟议的项目是创新的 因为它将从新颖的方法到心脏再生产生独特的机械见解 将心脏肌纤维细胞从增殖和纤维化表型转化为促血管生成和促促血管生成 再生表型。我们专注于EZH2介导的染色质重塑的表观抑制作用 GATA4介导的CPC程序在翻译上具有重要意义，因为EZH2抑制剂在临床上可用，并且具有 最近被批准用于治疗卵泡淋巴瘤。我们的初步发现突出了潜力 为了使这一途径成为缓解心脏纤维化并促进心脏的新型策略的重点 缺血性损伤后血管生成。