Alleviating Reactive Carbonyl Species-Induced Progenitor Cell Dysfunction in Diabetic Wound Healing

减轻糖尿病伤口愈合中反应性羰基物质诱导的祖细胞功能障碍

基本信息

批准号：
10221677
负责人：
TERRENCE J. MONKS
金额：
$ 37.48万
依托单位：
WAYNE STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-02 至 2023-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10221677
关键词：
Address Adenovirus Vector Adult Advanced Glycosylation End Products Affect American Amino Acids Amputation Animal Model Animals Attenuated Binding Blood Vessels Bone Marrow Cell Count Cell Therapy Chronic Data Detection Diabetes Mellitus Diabetic Foot Ulcer Endothelium Energy Metabolism Engineered Gene Enzymes Functional disorder Gene Transfer Generations Glucose Goals Health Homing Human Impaired wound healing Impairment In Vitro Innovative Therapy Inositol Knockout Mice Knowledge Lactoylglutathione Lyase Mediating Methodology Modification Molecular Mutate Organ Outcome Study Patients Pilot Projects Plasma Play Proteins Proteomics Protocols documentation Pyruvaldehyde Refractory Regimen Reporting Research Reticulum Ribonucleases Role Site Stress System Technology Testing Therapeutic Therapeutic Effect Tissues Type 2 diabetic Ulcer adduct angiogenesis base biological adaptation to stress chronic wound db/db mouse diabetic diabetic patient diabetic ulcer diabetic wound healing efficacy testing endoplasm endothelial stem cell functional loss gain of function genetic manipulation glycation healing improved in vivo liquid chromatography mass spectrometry loss of function neovascularization non-healing wounds novel novel therapeutic intervention novel therapeutics overexpression precursor cell prevent progenitor response sensor skin wound stem cell function stem cell therapy stem cells therapeutic development therapeutic target therapy design tissue repair wound wound closure wound healing wound treatment

项目摘要

PROJECT SUMMARY Refractory wounds in diabetic patients often result in amputation. Bone marrow derived endothelial progenitor cells (EPCs) actively participate in wound repair through angiogenesis after homing to the wounding site. However, progenitor cell functions are impaired in diabetes with mechanisms poorly understood. Reactive carbonyl species (RCS) are the intermediates and by-products generated during energy metabolism. Our pilot studies demonstrate one of the most potent RCS and the major precursor of the advanced glycation endproducts (AGE), methylglyoxal (MGO), exerted immediate inhibitory effects on progenitor cell functions in vitro. The glyoxalase I (GLO1), the key enzyme detoxifying MGO, was deficient in diabetic EPCs. These observations unveil an important message: Theses RCS actually play a major role in compromising progenitor cell function in diabetes, and this is due to the deficient glyoxalase defense system. The Major Goal of this project is to understand the molecular mechanisms of disrupted angiogenesis induced by RCS and to identify therapeutic targets for diabetic wound repair. Our recent report has demonstrated that an endoplasm reticulum response sensor, Inositol-Requiring Enzyme 1α (IRE1α), is essential to progenitor cell-mediated angiogenesis during wound repair. The endothelial-specific deletion of IRE1α leads to aberrant wound angiogenesis in vivo. However, how IRE1α functionality in EPCs is damaged in diabetes is not clear yet. Our pilot data strongly suggest that MGO directly diminishes IRE1α’s ribonuclease (RNase) function, and that IRE1α activation in EPCs is severely inhibited by MGO but rescued by GLO1 over-expression. We further found out that chronic wounds in diabetic animals started to heal upon receiving GLO1 gene transfer in vivo. Based on these findings, we propose Central Hypothesis that accumulated MGO in diabetes compromises progenitor cell function via interfering with IRE1α function, resulting in disrupted angiogenesis and delayed wound healing. To test the hypothesis, we propose Three Specific Aims: 1) Elucidate mechanisms by which MGO causes EPC dysfunction and IRE1α deficiency in diabetes in vitro; 2) Determine the molecular basis for MGO-induced IRE1α deficiency in vitro; 3) Determine the therapeutic effects of lowering MGO in diabetic wound healing in vivo. Our proposed studies will use newly developed Liquid chromatography–mass spectrometry (LC-MS) protocol to quantify free MGO accumulation in human plasma and diabetic foot ulcer tissues, representing the first effort to acquire the dynamic changes of free MGO generation in the microenvironment. We will employ both gain-of-function and loss-of-function technologies for gene manipulations, IRE1α gene engineered animals, and a newly established chronic diabetic wound animal model with cell therapies. Our project will allow us to uncover novel molecular mechanisms of impaired angiogenesis and wound healing in diabetes in which RCS-induced progenitor cell dysfunction is playing a pivotal role. Findings from this project will provide valuable information for novel therapeutics development for diabetic wound healing by augmenting RCS scavenger GLO1 or ER stress response sensor IRE1α.

项目概要糖尿病患者的难治性伤口常常导致骨髓来源的内皮祖细胞截肢。细胞（EPC）归巢到受伤部位后通过血管生成积极参与伤口修复。然而，祖细胞功能在糖尿病中受损，其机制尚不清楚。羰基物质（RCS）是我们的试点过程中产生的中间体和副产品。研究证明最有效的 RCS 之一和高级糖基化终产物的主要前体 (AGE)、甲基乙二醛 (MGO) 在体外对祖细胞功能产生直接抑制作用。乙二醛酶 I (GLO1) 是 MGO 解毒的关键酶，在糖尿病 EPC 中缺乏这些观察结果。揭示了一个重要信息：这些 RCS 实际上在损害祖细胞功能中发挥着重要作用糖尿病，这是由于乙二醛酶防御系统缺陷造成的。该项目的主要目标是了解 RCS 诱导的血管生成破坏的分子机制并确定治疗方法我们最近的报告表明，内质网反应是糖尿病伤口修复的目标。肌醇需求酶 1α (IRE1α) 传感器对于祖细胞介导的血管生成至关重要 IRE1α 的内皮特异性缺失会导致体内伤口血管生成异常。 EPC 中的 IRE1α 功能在糖尿病中如何受损尚不清楚。我们的试验数据强烈表明这一点。 MGO 直接削弱 IRE1α 的核糖核酸酶 (RNase) 功能，并且 EPC 中的 IRE1α 激活严重我们进一步发现，糖尿病患者的慢性伤口受到MGO的抑制，但被GLO1的过度表达所拯救。根据这些发现，动物在体内接受 GLO1 基因转移后开始愈合。假设糖尿病中积累的 MGO 通过干扰 IRE1α 损害祖细胞功能功能，导致血管生成中断和伤口愈合延迟。为了检验这一假设，我们提出。三个具体目标：1) 阐明 MGO 导致 EPC 功能障碍和 IRE1α 缺陷的机制体外糖尿病；2) 确定体外 MGO 诱导的 IRE1α 缺陷的分子基础；我们提出的研究将在体内使用新的降低 MGO 对糖尿病伤口愈合的治疗效果。开发了液相色谱-质谱 (LC-MS) 方案来量化游离 MGO 的积累人类血浆和糖尿病足溃疡组织，代表了获得自由动态变化的首次努力微环境中的 MGO 生成我们将采用功能获得和功能丧失技术。用于基因操作、IRE1α基因工程动物和新建立的慢性糖尿病伤口动物我们的项目将使我们能够揭示受损的新分子机制。糖尿病中的血管生成和伤口愈合，其中 RCS 诱导的祖细胞功能障碍发挥着重要作用该项目的研究结果将为新疗法的开发提供有价值的信息。通过增强 RCS 清除剂 GLO1 或 ER 应激反应传感器 IRE1α 来促进糖尿病伤口愈合。