Reactive nitrogen species and accelerated atherosclerosis in type I diabetes

I 型糖尿病中的活性氮和加速动脉粥样硬化

基本信息

批准号：
8604403
负责人：
MING-HUI ZOU
金额：
$ 36.26万
依托单位：
UNIVERSITY OF OKLAHOMA HLTH SCIENCES CTR
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-09-30 至 2018-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8604403
关键词：
26S proteasome 3-nitrotyrosine Abbreviations Acceleration Active Sites Address Affect Anions Antioxidants Arginine Atherosclerosis Binding Binding Sites Chronic Coupled Crossbreeding Cysteine Data Development Diabetes Mellitus Diabetic mouse Dose Endothelial Cells Endothelium Enzymes Funding GTP Cyclohydrolase I Glucose Goals Guanosine Triphosphate Half-Life Histidine Human Hydrogen Peroxide Hyperglycemia Insulin-Dependent Diabetes Mellitus Ions Kindling (Neurology)Knock-out Knockout Mice L-Glucose Lesion Low Density Lipoprotein Receptor MG132 Maintenance Mass Spectrum Analysis Metabolic stress Modification Molecular Mus Mutation NG-Nitroarginine Methyl Ester Nitric Oxide Oxidants Oxidative Stress Peptide Mapping Peroxonitrite Proteasome Inhibitor Proteins Publishing Reactive Nitrogen Species Reactive Oxygen Species Recombinants Reporting Resistance Role Source Streptozocin Stress Structure Sulfhydryl Compounds Superoxide Dismutase Superoxides Supplementation System Testing Transgenic Mice Transgenic Organisms UCP2 protein Ubiquitin Ubiquitination Uric Acid Zinc arginine methyl ester cofactor effective therapy enzyme activity exposed human population human NOS3 protein in vivo inhibitor/antagonist mouse model multicatalytic endopeptidase complex mutant novel overexpression oxidation prevent protein protein interaction public health relevance tetrahydrobiopterin

项目摘要

DESCRIPTION (provided by applicant): During last funding period, we have found that reactive nitrogen species such as peroxynitrite (ONOO-) uncouples endothelial nitric oxide synthase (eNOS) {generates superoxide anions (O2.-) or ONOO- instead of nitric oxide (NO)} and that eNOS uncoupling in diabetes causes accelerated atherosclerosis. Further, we found that tetrahydrobiopterin (BH4) deficiency, an essential cofactor for eNOS, is the key in the development of eNOS uncoupling in diabetes. Finally, we report that BH4 deficiency is due to rapid degradation of GTP cyclohydrolase I (GTPCH1; E.C. 3.5.4.16), the rate-limiting enzyme in BH4 de novo synthesis, by ubiquitin-proteasome system (UPS) in endothelial cells. However, why GTPCH1 is affected by diabetes hasn't been addressed. Thus, this project will test the hypothesis that oxidation of the zinc-binding structures of GTPCH1 inactivates the enzyme resulting in BH4 deficiency with consequent eNOS uncoupling in diabetes. Aim 1 is establish the essential role of zinc in maintaining GTPCH1 activity and stability and if oxidative disruption of the zinc-cysteine- histidine complexation in GTPCH1 enhances ubiquitination and consequent proteasomal degradation. Aim 2 is to investigate the molecular mechanisms by which hyperglycemia inhibits GTPCH1 in endothelial cells. Aim 3 is to determine the contributions of ONOO--induced GTPCH1 inhibition and ubiquitination in diabetes-enhanced atherosclerosis in mouse models of atherosclerosis in vivo. We believe that the proposed studies will provide novel information as to how the metabolic stress associated with diabetes causes damage to the endothelium and how the endothelial cell attempts to protect itself against these stresses and whether scavenging ONOO- is an effective therapy for diabetes.

DESCRIPTION (provided by applicant): During last funding period, we have found that reactive nitrogen species such as peroxynitrite (ONOO-) uncouples endothelial nitric oxide synthase (eNOS) {generates superoxide anions (O2.-) or ONOO- instead of nitric oxide (NO)} and that eNOS uncoupling in diabetes causes accelerated atherosclerosis.此外，我们发现四氢无菌蛋白酶（BH4）缺乏症是eNOS的必不可少的辅助因子，是糖尿病中eNOS解偶联的关键。最后，我们报告说，BH4缺乏症是由于GTP环氢酶I（GTPCH1; E.C. 3.5.4.16）的快速降解，这是内皮细胞中泛素蛋白 - 蛋白酶体系统（UPS）中BH4 de Novo合成中的速率限制酶。但是，为什么GTPCH1受糖尿病的影响尚未得到解决。因此，该项目将检验以下假设：GTPCH1的锌结合结构的氧化会使酶失活，从而导致BH4缺乏，从而导致糖尿病中的eNOS解偶联。 AIM 1是确定锌在维持GTPCH1活性和稳定性以及GTPCH1中锌 - 半胱氨酸 - 组氨酸络合的氧化破坏中的重要作用，会增强泛素化并随之增强蛋白酶体降解。目的2是研究高血糖抑制内皮细胞中GTPCH1的分子机制。 AIM 3是确定Onoo诱导的GTPCH1抑制和泛素化在体内动脉粥样硬化模型中的糖尿病增强动脉粥样硬化的贡献。我们认为，拟议的研究将提供有关与糖尿病相关的代谢压力如何损害内皮以及内皮细胞如何试图保护自己免受这些胁迫的损害的新信息，以及是否有效地对糖尿病进行了治疗。