Deciphering the Relationship Between Cardiomyocyte Metabolic Configuration and Cell Cycle Re-entry

破译心肌细胞代谢结构与细胞周期重入之间的关系

• 批准号: 10545018
• 负责人: Riham Abouleisa
• 金额: $ 8.33万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10545018
• 关键词: Adult; Affect; Anabolism; CDC2 gene; CDK4 gene; Carbon; Cardiac Myocytes; Cell Cycle; Cell Cycle Regulation Pathway; Cell Proliferation; Cell division; Cells; Collaborations; Cyclin D1; Cytokinesis; Data; Development; Down-Regulation; Echocardiography; Energy Metabolism; Fetus; Foundations; Gene Expression Regulation; Genes; Heart; Heart Diseases; Heart failure; Hexosamines; Hip region structure; Histology; Human; Infarction; Knowledge; Label; Link; Metabolic; Metabolism; Mitochondria; Modeling; Mus; Muscle Cells; Myocardial; Myocardial Infarction; Myocardium; Natural regeneration; Pathway interactions; Patients; Pentosephosphate Pathway; Phosphoenolpyruvate Carboxylase; Proliferating; Protocols documentation; Rattus; Respiration; Salamander; Serine; Technology; Up-Regulation; Viral; Virus; Zebrafish; cardiac repair; cyclin B1; enzyme pathway; fatty acid oxidation; glucose metabolism; heart function; in vivo; induced pluripotent stem cell derived cardiomyocytes; metabolomics; mouse model; novel strategies; novel therapeutics; overexpression; pharmacologic; postmitotic; programs; stable isotope; transcriptome sequencing

Myocardial infarction causes irreversible loss of cardiomyocytes (CMs) and often leads to heart failure. To replace the lost cells, we identified a combination of cell-cycle regulators that induces stable cytokinesis in adult post-mitotic cells. Overexpression of cyclin-dependent kinase 1 (CDK1), CDK4, cyclin B1, and cyclin D1 (referred to as 4F) promotes cell division in post-mitotic mouse, rat, and human cardiomyocytes. The high efficiency of this protocol in inducing myocyte renewal provides new opportunities for understanding the mechanisms involved in cardiomyocyte proliferation. One of the most interesting findings related to this discovery was the confirmation of a link between metabolic reprogramming and cardiomyocyte proliferation. Although in proliferating cells there is a strong correlation between metabolic changes and cellular proliferation, it remains unclear how metabolism influences the proliferative potential of cardiomyocytes. During the past 2 years, in collaboration with Dr. Hill’s group, I have generated preliminary data which indicate that cardiomyocyte proliferation is associated with marked reprogramming in energy metabolism. In proliferating cardiomyocytes isolated from lineage tracing (MADM) mice, RNA-seq data indicate profound downregulation of fatty acid oxidation genes and upregulation of biosynthetic pathway enzyme expression; in human iPSC-derived cardiomyocytes (hiPSC-CMs), 4F expression decreases mitochondrial respiration and catabolic activities. Using stable isotope-resolved metabolomics (SIRM), we demonstrate that 4F-infected hiPS-CMs show significant elevation in 13C labeled intermediates or end products of the hexosamine biosynthetic pathway (HBP), serine biosynthesis pathway (SBP), and pentose phosphate pathway (PPP). In line with these findings, our results also demonstrate that augmenting the carbon availability for these biosynthetic pathways by overexpressing phosphoenolpyruvate carboxykinase (PCK1 or PCK2) augments the ability of cardiomyocytes to proliferate. These data suggest that higher biosynthetic pathway flux may be required for cardiomyocyte proliferation. Informed by these results, we propose the general hypothesis that activation of ancillary biosynthetic pathways of glucose metabolism are required for cardiomyocyte proliferation. We suggest that higher biosynthetic pathway flux is required for building block synthesis and may be important for regulating pro-proliferative gene programs. During this project we will delineate the importance of each biosynthetic pathway in influencing cardiomyocyte proliferation. First, using pharmacological and virus-based approaches, we will determine the specific contribution of the HBP, SBP and PPP pathways to myocyte proliferation. In addition, we will investigate the influence of increasing the carbon flux in biosynthetic pathway through overexpression of PCK1, or PCK2 on cardiac function and repair in vivo. The aims of this project are: Specific Aim 1: Delineate the contribution of each biosynthetic pathway on cardiomyocyte proliferation. Specific Aim 2: Investigate the functional efficacy of increasing carbon flux in biosynthetic pathways on cardiac repair in vivo.

心肌梗塞会导致心肌细胞（CM）不可逆的损失，并常常导致心力衰竭。到 替换丢失的细胞，我们确定了细胞周期调节剂的组合，可诱导成人稳定的胞质分裂 有丝分裂后细胞。细胞周期蛋白依赖性激酶 1 (CDK1)、CDK4、细胞周期蛋白 B1 和细胞周期蛋白 D1 的过表达（称为 至 as 4F) 促进有丝分裂后小鼠、大鼠和人心肌细胞的细胞分裂。效率高 该诱导心肌细胞更新的方案为理解所涉及的机制提供了新的机会 在心肌细胞增殖中。与这一发现相关的最有趣的发现之一是证实 代谢重编程和心肌细胞增殖之间的联系。尽管在增殖细胞中存在 代谢变化与细胞增殖之间存在很强的相关性，但目前尚不清楚代谢如何发生 影响心肌细胞的增殖能力。在过去的两年中，与 Hill 博士合作 小组，我已经生成了初步数据，表明心肌细胞增殖与 能量代谢的显着重编程。在从谱系追踪中分离出的增殖心肌细胞中 (MADM) 小鼠，RNA-seq 数据表明脂肪酸氧化基因的深度下调和脂肪酸氧化基因的上调 生物合成途径酶的表达；在人 iPSC 衍生的心肌细胞 (hiPSC-CM) 中，4F 表达 降低线粒体呼吸和分解代谢活动。使用稳定同位素解析的代谢组学 (SIRM)，我们证明 4F 感染的 hiPS-CM 显示 13C 标记的中间体或 己糖胺生物合成途径 (HBP)、丝氨酸生物合成途径 (SBP) 和戊糖的终产物 磷酸途径（PPP）。与这些发现一致，我们的结果还表明，增加碳排放 通过过表达磷酸烯醇丙酮酸羧激酶（PCK1 或 PCK2）增强心肌细胞增殖的能力。这些数据表明更高的生物合成 心肌细胞增殖可能需要通路通量。根据这些结果，我们提出一般 假设葡萄糖代谢的辅助生物合成途径的激活是 心肌细胞增殖。我们建议构建块需要更高的生物合成途径通量 合成，可能对于调节促增殖基因程序很重要。在这个项目期间我们将 描述每个生物合成途径在影响心肌细胞增殖中的重要性。首先，使用 基于药理学和病毒的​​方法，我们将确定 HBP、SBP 和 PPP 心肌细胞增殖途径。此外，我们将研究增加碳通量的影响 在生物合成途径中，通过过表达 PCK1 或 PCK2 对心脏功能和体内修复产生影响。这 该项目的目标是： 具体目标 1：描述每种生物合成途径对心肌细胞的贡献 增殖。具体目标 2：研究增加生物合成途径碳通量的功能功效 体内心脏修复。