Restoration of myocardial reparative function of diabetic progenitor cells by epigenetic modulation

通过表观遗传调节恢复糖尿病祖细胞的心肌修复功能

• 批准号: 10318627
• 负责人: Raj Kishore
• 金额: $ 56.03万
• 依托单位: TEMPLE UNIV OF THE COMMONWEALTH
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-10 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10318627
• 关键词: American; Animals; Attenuated; Azacitidine; Blood Vessels; Bone Marrow; CD34 gene; Cardiac; Cardiovascular Diseases; Cell Therapy; Cell division; Cells; Clinical; Clinical Trials; Coupled; DNA Modification Methylases; DNMT3a; Diabetes Mellitus; Diabetic mouse; Endothelium; Enzymes; Epigenetic Process; Functional disorder; G9a histone methyltransferase; Gene Expression; Genes; Goals; HDAC1 gene; Heart Diseases; Heart failure; Hematopoietic stem cells; Histone Acetylation; Histone Deacetylase; Histones; Human; Hyperglycemia; Impairment; In Vitro; Inherited; Lysine; Mediator of activation protein; Memory; Methylation; Methyltransferase; MicroRNAs; Modeling; Modification; Molecular; Morbidity - disease rate; Mus; Myocardial; Myocardial Infarction; Myocardial Ischemia; Natural regeneration; Non-Insulin-Dependent Diabetes Mellitus; Outcome; Patients; Pattern; Perfusion; Pharmaceutical Preparations; Phenotype; Physiological; Process; Property; Public Health; Publishing; Research; Role; Sequential Treatment; Testing; Tissues; Valproic Acid; Vascular Diseases; Vascular Endothelium; adult stem cell; angiogenesis; base; critical limb Ischemia; daughter cell; db/db mouse; diabetic; diabetic patient; differential expression; disability; endothelial stem cell; epigenetic silencing; exosome; experimental study; functional disability; gene repression; genome wide methylation; heart disease risk; histone modification; improved; in vivo; inhibitor; ischemic injury; limb ischemia; mortality; mouse model; neovascularization; novel strategies; novel therapeutic intervention; pre-clinical research; progenitor; programs; promoter; regenerative cell; repair function; repaired; reparative capacity; restoration; small molecule; small molecule inhibitor; stem cell function; stem cell survival; stem cells; targeted agent; tissue repair

In the absence of effective endogenous repair mechanisms after ischemic injury, cell-based therapies have emerged as a potential novel therapeutic approach in ischemic tissue repair. After the initial characterization of putative bone marrow-derived endothelial progenitor cells (EPC) and their potential to promote cardiac and critical limb ischemia neovascularization and to attenuate ischemic injury, more than a decade of intense preclinical research, led to the BM progenitors/EPC-based clinical trials. However, despite early enthusiasm, cell based therapies yielded modest clinical results. Modest clinical outcomes of cell-based therapies may reflect the cellular dysfunction that is known to ensue in EPC/progenitor cells obtained from diabetic animals as well as patients. Compelling evidence indicates that EPCs dysfunction represents a mechanism for impaired vascular repair and angiogenesis in diabetes, subsequently leading to vascular dysfunction. Therefore, understanding the molecular basis of diabetes-induced EPC dysfunction and potentially reversing EPC dysfunction may represent a strategy to enhance cell-based therapeutics for myocardial/ischemic limb repair in diabetic patients. Increasing evidence also indicates that the mechanism underlying hyperglycemic memory and EPC dysfunction may involve epigenetic mechanisms involving enhanced epigenetic repressive marks on vascular genes leading to their epigenetic silencing. Moreover, since hyperglycemic memory is inherited through cell division, and altered epigenetic patterns in diabetic EPCs can be transmitted to daughter cells. Understanding the epigenetic basis of EPC dysfunction in diabetics and epigenetic reprogramming of diabetic EPCs, is therefore, of paramount importance for cell based therapies in diabetic patients. Therefore, our central hypothesis is that epigenetic repressive marks in diabetic EPCs render them dysfunctional and epigenetic modifying agents targeting those repressive marks can reprogram diabetic EPCs to a more functional and reparative phenotype. This project aims to study, in detail, phenotypic, epigenetic and molecular characterization of reprogrammed diabetic EPCs from diabetic mice as well as human CD34+ hematopoietic stem cells from diabetic patients and their exosome derivatives and test the ischemic myocardial repair capacity of these reprogrammed diabetic EPCs in physiologically relevant model of MI and hind limb ischemia. This overall aim will be achieved by conducting experiments organized under the following three specific aims: 1) To evaluate phenotypic stability and reparative potential of epigenetically reprogrammed diabetic EPCs; 2) To determine the specific epigenetic modifications in reprogrammed EPCs and establish a role of HDAC1 and G9a methytransferase in reprogramming process and 3) To establish epigenetic reprogramming rescues functional and reparative deficits in human CD34+ stem cells from patients with Type 2 diabetes.

在缺血性损伤后缺乏有效的内源性修复机制的情况下，基于细胞的疗法应运而生 作为缺血组织修复的潜在新治疗方法。在对假定的骨骼进行初步表征后 骨髓源性内皮祖细胞（EPC）及其促进心脏和严重肢体缺血的潜力 新生血管形成和减轻缺血性损伤，经过十多年的深入临床前研究， 基于 BM 祖细胞/EPC 的临床试验。然而，尽管早期热情高涨，基于细胞的疗法却收效甚微。 临床结果。基于细胞的疗法的适度临床结果可能反映了已知的细胞功能障碍 发生在从糖尿病动物和患者身上获得的 EPC/祖细胞中。令人信服的证据表明 EPC 功能障碍代表了糖尿病中血管修复和血管生成受损的机制，随后 导致血管功能障碍。因此，了解糖尿病引起的 EPC 功能障碍的分子基础 潜在逆转 EPC 功能障碍可能是增强基于细胞的治疗的策略 糖尿病患者的心肌/缺血性肢体修复。越来越多的证据也表明该机制 潜在的高血糖记忆和 EPC 功能障碍可能涉及表观遗传机制，涉及增强 血管基因上的表观遗传抑制标记导致其表观遗传沉默。此外，由于高血糖 记忆通过细胞分裂遗传，糖尿病 EPC 中改变的表观遗传模式可以传递给 子细胞。了解糖尿病患者 EPC 功能障碍的表观遗传基础和表观遗传重编程 因此，糖尿病 EPCs 对于糖尿病患者的细胞疗法至关重要。因此，我们的 中心假设是糖尿病 EPC 中的表观遗传抑制标记使其功能失调且表观遗传 针对这些抑制标记的修饰剂可以将糖尿病 EPC 重新编程为更具功能性和修复性 表型。该项目旨在详细研究表型、表观遗传和分子特征 重编程糖尿病小鼠的糖尿病 EPC 以及糖尿病人 CD34+ 造血干细胞 患者及其外泌体衍生物，并测试这些重编程的缺血心肌修复能力 MI 和后肢缺血生理相关模型中的糖尿病 EPC。这一总体目标将通过 根据以下三个具体目标进行实验：1）评估表型稳定性和 表观遗传重编程糖尿病内皮祖细胞的修复潜力； 2）确定具体的表观遗传 重编程 EPC 的修饰并确定 HDAC1 和 G9a 甲基转移酶在重编程中的作用 3) 建立表观遗传重编程可挽救人类 CD34+ 的功能和修复缺陷 来自 2 型糖尿病患者的干细胞。