Role of Inositol requiring enzyme 1 in regulating angiogenesis for diabetic wound repair.

需要酶 1 的肌醇在调节糖尿病伤口修复血管生成中的作用。

• 批准号: 9222758
• 负责人: Jiemei Wang
• 金额: $ 34.65万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-01 至 2021-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9222758
• 关键词: ANGPT1 gene; Affect; American; Amputation; Angiogenic Factor; Attenuated; Biochemical; Biological Assay; Bone Marrow; Cell Therapy; Cell physiology; Data; Diabetes Mellitus; Diabetic mouse; Diabetic wound; Down-Regulation; Endoplasmic Reticulum; Endothelium; Enzymes; Family; Family member; Functional disorder; Future; Gene Targeting; Gene Transfer; Genes; Genetic; Health; Homing; Human; Impaired wound healing; Impairment; In Vitro; Inositol; Intervention; Investigation; Knockout Mice; Knowledge; Lead; Link; LoxP-flanked allele; Mediating; Metabolic; MicroRNAs; Microarray Analysis; Molecular; Mus; Non-Insulin-Dependent Diabetes Mellitus; Outcome Study; Pathogenesis; Pathway interactions; Patient Recruitments; Patients; Pharmacology; Pilot Projects; Proteins; Publishing; RNA; RNA Splicing; Refractory; Regulation; Research; Role; Site; Skin Ulcer; Stem cells; Stress; Testing; Virus; Work; Wound Healing; adenoviral-mediated; angiogenesis; base; biological adaptation to stress; cell type; coping; db/db mouse; diabetic; diabetic patient; diabetic wound healing; endoplasmic reticulum stress; functional loss; gain of function; improved; in vivo; interest; loss of function; neovascularization; novel; novel therapeutic intervention; overexpression; peripheral blood; pre-miRNA; public health relevance; response; restoration; sensor; success; therapeutic development; tissue repair; vector; whole genome; wound; wound closure

 DESCRIPTION (provided by applicant): Refractory wounds in diabetic patients often result in amputation. Endothelial progenitors cells (EPC) actively participate in wound repair through angiogenesis after homing to the wounding site. However, EPC functions are impaired in diabetes with mechanisms poorly understood. Our pilot studies demonstrate a reduced activity of an important ER sensor ER sensor, Inositol requiring enzyme 1 (IRE1), and a decreased expression of a potent angiogenic factor angiopoietin-1 (ANGPT1) in EPCs from human and mice with type 2 diabetes, contribute to EPC dysfunction. Most importantly, our preliminary studies show that IRE1α suppresses a subset of microRNA (miR) clusters known to be detrimental to angiogenesis. We speculate that this suppression is due to IRE1α's direct splicing activity to precursor miRs (pre-miRs), resulting in depletion of functional miRs. Of particular interest, our preliminary data demonstrate that IRE1α deficiency significantly increased miR-200 family in EPCs from diabetic mice, leading to down-regulation of one of their target genes - ANGPT1. Yet how IRE1 regulates EPC function and wound repair in diabetes is unknown. Therefore, the objective in this proposal is to determine the mechanisms of IRE1 regulation of angiogenesis and wound repair. The hypothesis, built upon our extensive preliminary studies and published work, is that deficiency in IRE1α, leads to insufficient degradation of pre-miRNA in diabetes, resulting in impaired endothelial progenitor cell (EPC) angiogenesis and delayed wound healing. Our hypothesis will be tested in three specific aims: 1) Determine the molecular mechanisms underlying the essential role of IRE1α in maintaining EPC function in diabetes in vitro; 2) Determine how IRE1α-targeted pre-miR modulates EPC function in vitro; 3) Determine how IRE1α improves wound healing in diabetes in vivo. Our approaches encompass in vitro and in vivo studies utilizing adenovirus-mediated gene manipulations, whole genome RNA profiling, IRE1α floxed mice and newly generated endothelium-specific IRE1α knockout mice. Furthermore, human EPCs will be obtained from type 2 diabetic patients and healthy subjects in order to determine the levels of IRE1α pathway and miRs. The proposed study is significant, because it will uncover a previously unrecognized role of the ER stress response in impaired angiogenesis and wound healing in diabetes at the translational level. The investigation of IRE1α-mediated regulation of stress miRs will open a new paradigm for the study of the molecular mechanisms responsible for pathogenesis of refractory wounds, which will enable future development of therapeutics for this devastating situation affecting millions of Americans.

 描述（由适用提供）：糖尿病患者的难治性伤口通常会导致截肢。内皮祖细胞（EPC）在归蜜之后通过血管生成积极参与伤口修复。但是，EPC功能在糖尿病中受到损害，其机制知之甚少。我们的试点研究表明，重要的ER传感器传感器，需要酶1（IRE1）的肌醇的活性降低，以及在2型糖尿病的人和小鼠中，潜在的血管生成因子Angiopietin-1（ANGPT1）的表达降低，导致EPC功能障碍。最重要的是，我们的初步研究表明，IRE1α抑制了已知对血管生成有害的microRNA（miR）簇的子集。我们推测这种抑制是由于IRE1α对前体miR的直接剪接活性（前MIRS）引起的，导致功能miR的耗竭。特别令人感兴趣的是，我们的初步数据表明，IRE1α缺乏症显着增加了来自糖尿病小鼠的EPC中的miR-200家族，导致其目标基因之一 - ANGPT1的下调。然而，IRE1如何调节糖尿病的EPC功能和伤口修复尚不清楚。因此，该提案的目的是确定IRE1调节血管生成和伤口修复的机制。该假设基于我们广泛的初步研究和发表的工作，是IRE1α缺乏，导致糖尿病前MIRNA降解不足，从而导致内皮祖细胞（EPC）血管生成受损和伤口延迟愈合。我们的假设将以三个特定目的进行检验：1）确定IRE1α在体外糖尿病中维持EPC功能中至关重要的基本作用的基本作用的分子机制； 2）确定IRE1α靶向前MIR如何在体外调节EPC功能； 3）确定IRE1α如何改善体内糖尿病的伤口愈合。我们的方法涵盖了利用腺病毒介导的基因操纵，整个基因组RNA分析，IRE1α氟脱毒小鼠以及新产生的内皮特异性IRE1α敲除小鼠的方法涵盖体外和体内研究。此外，将从2型糖尿病患者和健康受试者中获得人类EPC，以确定拟议的研究很重要，因为它将发现ER应激反应在翻译水平的糖尿病中的血管生成和伤口愈合中的先前未识别的作用。 IRE1α介导的压力miR的投资将为研究负责难治性伤口发病机理的分子机制打开新的范式，这将使未来的治疗发展为影响数百万美国人的这种毁灭性状况。