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.

项目摘要糖尿病患者的难治性伤口通常会导致截肢。骨髓衍生的内皮祖细胞细胞（EPC）在归巢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到损害，机制的理解差。反应性羰基（RCS）是能量代谢过程中产生的中间体和副产品。我们的飞行员研究证明了最有效的RC和晚期糖基化最终产物的主要前体之一（年龄），甲基糖（MGO），在体外对祖细胞功能产生了立即抑制作用。这糖酶I（GLO1），关键的酶排毒MGO，缺乏糖尿病EPC。这些观察揭示一条重要的消息：THES RCS实际上在妥协的祖细胞功能中起主要作用糖尿病，这是由于不足的乙二醛酶防御系统。该项目的主要目标是了解RC诱导的干扰血管生成的分子机制并鉴定治疗糖尿病伤口修复的目标。我们最近的报告表明内质网状反应传感器，肌醇提高酶1α（IRE1α），对于祖细胞细胞介导的血管生成至关重要伤口修复。 IRE1α的内皮特异性缺失导致体内的伤口异常。然而， EPC中的IRE1α功能在糖尿病中尚不清楚。我们的飞行员数据强烈表明 MGO直接降低IRE1α的核糖核酸酶（RNase）功能，并且EPC中的IRE1α激活严重被MGO抑制，但被GLO1过表达救出。我们进一步发现糖尿病患者的慢性伤口动物在体内接受GLO1基因转移后开始愈合。根据这些发现，我们提出了中央假设在糖尿病中积累的MGO通过干扰IRE1α损害了祖细胞功能功能，导致血管生成干扰并延迟伤口愈合。为了检验假设，我们提出三个特定目的：1）阐明MGO引起EPC功能障碍和IRE1α缺乏症的机制在体外糖尿病中； 2）确定体外MGO诱导的IRE1α缺乏的分子基础； 3）确定在体内降低MGO降低MGO的治疗作用。我们提出的研究将使用新的开发的液相色谱 - 质谱法（LC-MS）方案，以量化自由MGO积累人血浆和糖尿病足溃疡组织，这是获得自由变化的首次努力 MGO在微环境中产生。我们将采用功能收益和功能丧失技术对于基因操纵，IRE1α基因工程动物和新建立的慢性糖尿病伤口具有细胞疗法的模型。我们的项目将使我们能够发现受损的新型分子机制 RCS诱导的祖细胞功能障碍的糖尿病血管生成和伤口愈合正在发挥关键作用。该项目的发现将为新的治疗开发提供有价值的信息糖尿病伤口通过增加RCS清除剂GLO1或ER应力反应传感器IRE1α来愈合。