Endothelial precursor dysfunction in development of diabetic acellular capillary

糖尿病脱细胞毛细血管发育中的内皮前体功能障碍

基本信息

批准号：
7643154
负责人：
Maria Bartolomeo Grant
金额：
$ 43.14万
依托单位：
UNIVERSITY OF FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
1998
资助国家：
美国
起止时间：
1998-09-30 至 2010-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7643154
关键词：
Acetylcholine Actins Acute Adherence Adult Advanced Glycosylation End Products Affect Age Animal Model Animals Area Arts Biochemical Biological Biological Assay Biological Availability Blindness Blood Vessels Blood capillaries Blood flow Bradykinin Brain Hypoxia-Ischemia CD34 gene Cell Death Cell-Matrix Junction Cells Chronic Collagen Type IV Confocal Microscopy Cyclic GMP Cyclic GMP-Dependent Protein Kinases Cytokine Receptors Cytoskeleton DNA Sequence Rearrangement Data Defect Development Diabetes Mellitus Diabetic Retinopathy Diabetic mouse Down-Regulation Dropout Endothelial Cells Endothelium Environment Epithelial Equilibrium Fluorescence Microscopy Functional disorder Generations Grant Growth Factor Hematopoietic Home environment Human Hypoxia Image In Vitro Individual Injection of therapeutic agent Injury Ischemia Lead Lesion Maintenance Mediator of activation protein Membrane Microfilaments Migration Assay Modeling Molecular Molecular Motors Motor Mutate Nature Nitric Oxide Nitric Oxide Donors Nitric Oxide Signaling Pathway Nitric Oxide Synthase Nude Mice PECAM1 gene Pathway interactions Patients Pericytes Phosphorylation Site Pigments Play Population Process Property Protein Isoforms Proteins Regulation Reperfusion Injury Research Personnel Retina Retinal Reverse Transcriptase Polymerase Chain Reaction Rodent Rodent Model Role Secondary to Signal Transduction Staining method Stains Streptozocin Stromal Cell-Derived Factor 1 Substance P Techniques Testing Time Transfection Vascular Endothelial Growth Factor Receptor Vascular Endothelial Growth Factors Western World Work base capillary cell motility cell type diabetic diabetic patient glycation glycosylated fibronectin injured matrigel migration non-diabetic novel pigment epithelium-derived factor polymerization precursor cell programs proliferative diabetic retinopathy repaired response retinal ischemia stem tool vasodilator-stimulated phosphoprotein

项目摘要

DESCRIPTION (provided by applicant): Diabetic retinopathy (DR) is a primary cause of blindness of working age adults in the Western world. Early pericyte dropout and endothelial cell death result in the formation of acellular capillaries, which cause retinal hypoxia and ischemia and are important contributors to DR development. We have shown have that hematopoietic stem and endothelial precursor cells (EPC) readily home to the retina in healthy animals, but that EPC of diabetic animal and humans have a migratory defect. Our preliminary studies demonstrate that EPC dysfunction may provide a novel mechanism for development of acellular capillaries in diabetic retinopathy. Our data suggest that within EPCs, nitric oxide (NO) plays a key role in regulating the actin polymerization mediator, vasodilator-stimulated phosphoprotein (VASP). In diabetes, reduced bioavailability of NO can occur as a result of alterations in growth factor/cytokine receptor balance, downstream signaling, or downregulation of NO synthase (NOS) activation. Reduced NO can alter actin polymerization affecting EPC migration and their ability to carry out endothelial repair. Our hypothesis is that in diabetic individuals reduced NO bioavailability results in decreased EPC migration, attachment and invasion contributing to inadequate endothelial repair and development of acellular capillaries. State-of-the- art imaging, fluorescent activated cell sorter analysis, novel in vitro culture assays and diabetic animal models will be used in combination with biochemical and molecular biological techniques to test our hypothesis. We propose the following specific aims: Specific Aim 1: Our hypothesis predicts that diabetic EPCs will be unable to home to the retina and repopulate acellular capillaries whereas EPCs from normals will. Diabetic mice that have developed acellular retinal capillaries will be injected systemically with EPCs from nondiabetic rodents and the degree of vascular repair examined. Specific Aim 2: Our hypothesis predicts that NO regulates EPC migration .directly by promoting cytoskeletal changes. We will determine which factors regulate EPC NOS isoform expression and NO generation and delineate the NO signaling pathway that regulates cytoskeletal dysfunction in diabetic EPCs. Specific Aim 3: Our hypothesis predicts that diabetic CD34+ EPC cells have defective attachment and invasion. We will determine whether EPC attachment is dependent upon inherent properties of the EPC or the local matrix environment and evaluate human diabetic and nondiabetic CD34+ cell attachment to normal and glycated matrix. The exciting implication of our hypothesis is that early repair of the EPC migratory defect may deter the subsequent development of proliferative diabetic retinopathy.

描述（由申请人提供）：糖尿病性视网膜病（DR）是西方世界成年成年人失明的主要原因。早期的周细胞辍学和内皮细胞死亡导致细胞毛细血管的形成，这会导致视网膜缺氧和缺血，并且是DR发育的重要促进者。我们已经表明，造血茎和内皮前体细胞（EPC）很容易成为视网膜健康动物中的视网膜，但是糖尿病动物和人类的EPC具有迁移性缺陷。我们的初步研究表明，EPC功能障碍可能为糖尿病性视网膜病中毛细血管发展的新机制提供了新的机制。我们的数据表明，在EPCS中，一氧化氮（NO）在调节肌动蛋白聚合介质血管扩张剂刺激的磷酸蛋白（VASP）中起关键作用。在糖尿病中，由于生长因子/细胞因子受体平衡，下游信号传导或NO合酶（NOS）激活的下调，可能会导致降低NO的生物利用度。降低的没有可以改变影响EPC迁移的肌动蛋白聚合及其进行内皮修复的能力。我们的假设是，在糖尿病患者中，没有生物利用度降低会导致EPC迁移，依恋和侵袭减少，导致内皮毛细血管的内皮修复和发育不足。最先进的成像，荧光活化的细胞分析剂分析，新型体外培养试验和糖尿病动物模型将与生化和分子生物学技术结合使用，以检验我们的假设。我们提出以下特定目的：具体目标1：我们的假设预测糖尿病EPC将无法回家视网膜并重新填充细胞毛细血管，而来自正常的EPC则将。患有无细胞视网膜毛细血管的糖尿病小鼠将全系统地注入来自非糖尿病啮齿动物的EPC和检查的血管修复程度。具体目的2：我们的假设预测，没有通过促进细胞骨架变化直接调节EPC迁移。我们将确定哪些因素调节EPC NOS同工型表达，并且没有产生，并描绘了调节糖尿病EPC中细胞骨架功能障碍的无信号传导途径。特定目标3：我们的假设预测糖尿病CD34+ EPC细胞的附着和侵袭有缺陷。我们将确定EPC附件是否取决于EPC或局部基质环境的固有特性，并评估人类糖尿病和非糖尿病性CD34+细胞附着在正常和糖化基质上。我们假设的令人兴奋的含义是，EPC迁移缺陷的早期修复可能会阻止随后的增殖性糖尿病性视网膜病的发展。