Elucidating the Molecular Mechanisms and Cellular Specificity of HDAC Inhibitor Efficacy in Diastolic Dysfunction

项目总结 以左心室顺应性和舒张性受损为特征的舒张期功能障碍(DD)与 随着射血分数保留(HFpEF)而发展为心力衰竭的风险增加，这是一种毁灭性的综合征 预后不佳，目前对其治疗干预措施有限。乙酸乙酯的动态乙酰化 组蛋白是染色质依赖的信号转导的关键组成部分，参与激活 心脏成纤维细胞(CFs)和细胞外基质沉积增加，导致进展性DD和 高频脉冲电场的发展。这些过程在很大程度上由组蛋白脱乙酰酶(HDAC)调节，组蛋白脱乙酰酶是一类 表观遗传调节酶，其药理抑制在DD环境中具有心脏保护作用； 然而，关于hdac异构体的特异性和介导这一过程的分子机制，我们知之甚少。 保护。这一独立之路奖将利用创新的小分子抑制剂、遗传学- 基于细胞类型特定基因消融的策略，以及多方面的最先进技术的集成 用表观基因组学和生物信息学技术检测HDAC抑制的细胞类型和异构体特异性 (目标1和2)，以及抑制一种新的糖蛋白结合蛋白(目标3)在肌成纤维细胞中的治疗潜力 活化、心肌纤维化和DD。在目标1和目标2中，申请者将与合作导师和顾问一起在 K99期在单细胞、全基因组的下一代测序技术中的应用 架构，一种基于流式细胞术的表征炎症细胞的技术，一种综合的方法 原代人类CFs的转录组学和蛋白质组学分析，以及基于遗传学的细胞类型- 特定的基因消融，所有这些都是为了确定细胞的特异性和分子机制 介导HDAC抑制的心脏保护作用。在目标3中描述的R00阶段，申请人 将利用在K99阶段获得的技能来研究抑制细胞生长的作用和治疗潜力 糖链结合蛋白Galectin-1，最近发现在小鼠的CF群中发生显著变化 DD和HDAC抑制在肌成纤维细胞激活、心脏重构和进展中的作用 到HFpEF。申请者在表观遗传学、CF生物学和 DD的病理生理与纤维化重塑。此外，导师团队由国际上的 在心血管疾病的表观遗传学调控、临床HFpEF、心力衰竭小鼠模型以及 新兴的生物信息学技术。科罗拉多大学安舒茨医学院的环境 是协作和创新研究的典范，拥有包括人类心脏在内的卓越基础设施 生物库和卓越的核心设施。总而言之，杰出的指导团队和机构 环境将为申请者发展成为独立的调查员提供坚实的基础。 此外，这种创新的方法提供了令人兴奋的潜力，为绝望的发展做出贡献 治疗心力衰竭需要新的治疗策略。

PROJECT SUMMARY Diastolic dysfunction (DD), characterized by impaired left ventricular compliance and relaxation, is associated with increased risk of developing heart failure with preserved ejection fraction (HFpEF), a devastating syndrome with poor prognosis for which there currently exist limited therapeutic interventions. Dynamic acetylation of histones represents a critical component of chromatin-dependent signal transduction involved in the activation of cardiac fibroblasts (CFs) and increased extracellular matrix deposition, leading to progressive DD and development of HFpEF. These processes are largely regulated by histone deacetylases (HDACs), a family of epigenetic regulatory enzymes whose pharmacological inhibition is cardioprotective in the setting of DD; however, little is known regarding the HDAC isoform specificity and molecular mechanisms mediating this protection. This Pathway to Independence award will leverage innovative small molecule inhibitors, genetics- based strategies for cell type-specific gene ablation, and the integration of multifaceted state-of-the-art epigenomic and bioinformatics techniques to examine the cell type- and isoform-specificity of HDAC inhibition (Aims 1 and 2), and therapeutic potential of inhibition of a novel glycan binding protein (Aim 3), in myofibroblast activation, cardiac fibrosis and DD. In Aims 1 and 2, the applicant will train with co-mentors and advisors in the K99 phase in a single-cell, genome-wide next generation sequencing technology that characterizes chromatin architecture, a flow cytometry-based technique for characterizing inflammatory cells, an integrated approach to transcriptomics and proteomics analyses in primary human CFs, and a genetics-based approach for cell type- specific gene ablation, all with the overall goal of defining the cellular specificity and molecular mechanisms mediating the cardioprotective properties of HDAC inhibition. In the R00 phase described in Aim 3, the applicant will utilize the skills acquired in the K99 phase to investigate the role and therapeutic potential of inhibiting the glycan-binding protein Galectin-1, recently discovered to be significantly altered in the CF population of mice with DD and subjected to HDAC inhibition, in myofibroblast activation, cardiac remodeling, and the progression to HFpEF. The applicant possesses extensive prior knowledge in epigenetics, CF biology, and the pathophysiology of DD and fibrotic remodeling. Furthermore, the mentorship team consists of internationally recognized leaders in epigenetic regulation of cardiovascular disease, clinical HFpEF, murine models of HF, and emerging bioinformatics technologies. The environment at the University of Colorado Anschutz Medical Campus is exemplary for collaborative and innovative research, with an excellent infrastructure including a human heart biorepository and outstanding core facilities. In summary, the exceptional mentoring team and institutional environment will provide a solid foundation for the applicant’s development into an independent investigator. Moreover, this innovative approach offers the exciting potential to contribute to the development of desperately needed novel therapeutic strategies for the treatment of heart failure.