NO Dysregulation of the Peripheral Clock in Diabetic Complications

糖尿病并发症中没有外周时钟失调

基本信息

批准号：
8152123
负责人：
Maria Bartolomeo Grant
金额：
$ 29.98万
依托单位：
UNIVERSITY OF FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-09-30 至 2014-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8152123
关键词：
Affect Albumins Animals Arterial Fatty Streak Atherosclerosis Binding Proteins Bioavailable Biological Availability Blindness Blood Circulation Blood Vessels Blood capillaries Bone Marrow Bone Marrow Cells Cell Aging Cell Maturation Cells Circadian Rhythms Clock protein Complications of Diabetes Mellitus Defect Development Diabetes Mellitus Diabetic Angiopathies Diabetic Retinopathy Down-Regulation Endothelial Cells Endothelium Equilibrium Feedback Frequencies Functional disorder Gene Expression Gene Targeting Genes Health Homeostasis Hyperplasia Injury Knock-out Knockout Mice Lead Literature Maintenance Metabolic Metabolic Control Modeling Molecular Neuropathy Nitric Oxide Non-Insulin-Dependent Diabetes Mellitus Organ Pacemakers Pathogenesis Pathology Pathway interactions Pattern Periodicity Peripheral Peroxisome Proliferator-Activated Receptors Peroxonitrite Phase Phenotype Plasminogen Plasminogen Activator Inhibitor 1 Plasminogen Inactivators Play Post-Translational Protein Processing Proteins Publishing Rattus Reactive Oxygen Species Regulation Retinal Role Site Stem cells Testing Vasa Nervorum Vasopressins Work arm base capillary cell type diabetic human NOS3 protein inhibitor/antagonist mortality new therapeutic target non-diabetic public health relevance repaired response to injury restoration therapeutic target

项目摘要

DESCRIPTION (provided by applicant): Using a rat model of type 2 diabetes (T2D), we showed that at 2 months of T2D the decrease in bone marrow progenitor cell (BMPC) release from diabetic bone marrow (BM) is caused by BM neuropathy and that these changes precede the development of diabetic retinopathy (DR). BM neuropathy was associated with a marked reduction in clock gene expression in the BMPCs themselves which led to diminished repair by these cells and by 4 months of T2D resulted in the hallmark feature of diabetic retinopathy (DR), acellular retinal capillaries. Diabetic BMPC dysfunction was corrected by increasing levels of bioavailable nitric oxide (NO) towards normal non-diabetic levels. Since NO modulates clock gene expression, the reduced levels of bioavailable NO results in altered clock gene expression. Plaminogen activator inhibitor (PAI-1), an important modulator of hematopoetic stem cell maturation and release from the BM is an immediate downstream metabolic regulator controlled by clock genes. PAI-1 demonstrates a robust circadian pattern in health, but this pattern is altered in diabetes and elevated levels are produced by endothelial cells (EC) from diabetics. We believe this NO-modulated clock gene dysfunction leads to the loss of circadian regulation of PAI-1 and represents an underlying mechanism and therapeutic target for DR and atherosclerosis, which are the major causes of blindness and mortality in diabetics, respectively. In this application, we propose the following hypothesis: In diabetes, a reduction in bioavailable NO in ECs and BMPCs causes a diminished amplitude and frequency of the oscillatory pattern of the clock proteins, BMAL1 and PER-2, leading to a loss of circadian regulation of PAI-1 and subsequent further diminution of NO levels in EC and BMPCs. Decreasing NO bioavailability and persistent increase in PAI-1 in the vasa nervorum leads to development of BM neuropathy which results in defective EPC mobilization further exacerbating end organ complications. To test our hypothesis, we propose the following aims: 1) to determine whether NO bioavailability can affect the molecular clock and circadian rhythms in vascular ECs and BMPCs and to determine whether levels of NO will have direct and indirect effects on clock gene expression via S-nitrosylation of essential clock proteins such as BMAL1 and PER-2; 2) to determine whether specific clock gene knock-out of the endothelium and BMPC recapitulates the diabetic vascular phenotype of accelerated injury and reduced repair; and 3) to determine whether dysregulation of NO and PAI-1 within the vasa nervorum leads to BM neuropathy and loss of circadian release of BMPCs into the circulation. PUBLIC HEALTH RELEVANCE: This proposal represents a paradigm shift in our understanding of the pathogenesis of diabetic micro- and macro-vascular complications. We are testing whether circadian oscillators play a pivotal role in endothelial cell and bone marrow progenitor cells homeostasis. We believe that when disrupted in diabetes, they must be restored before vascular health is achieved. We specifically identify plasminogen activator inhibitor as a novel therapeutic target in diabetes to restore vascular function and circadian oscillation of nitric oxide in vascular and bone marrow cells.

描述（由申请人提供）：使用2型糖尿病（T2D）的大鼠模型，我们表明，在T2D的2个月中，骨髓祖细胞（BMPC）从糖尿病骨髓（BM）释放的减少是由BM神经病引起的，并且这些变化在糖尿病性视网膜病（DR）的发展之前。 BM神经病与BMPC本身中时钟基因表达的显着降低有关，从而导致这些细胞的修复减少，到4个月的T2D导致了糖尿病性视网膜病变（DR）的标志性特征，Acellular视网膜毛细管。糖尿病BMPC功能障碍通过增加对正常非糖尿病水平的生物利用一氧化氮（NO）水平来纠正。由于没有调节时钟基因的表达，因此降低的生物利用水平没有导致时钟基因表达改变的结果。 Plaminogen活化剂抑制剂（PAI-1）是造血干细胞成熟和从BM释放的重要调节剂，是由时钟基因控制的立即下游代谢调节剂。 PAI-1在健康方面表现出强大的昼夜节律模式，但是这种模式在糖尿病中改变了，糖尿病患者的内皮细胞（EC）产生了升高的水平。我们认为，这种未经调节的时钟基因功能障碍会导致PAI-1调节的昼夜调节，并代表了DR和动脉粥样硬化的潜在机制和治疗靶标，这是糖尿病患者失明和死亡率的主要原因。在此应用中，我们提出了以下假设：在糖尿病中，ECS和BMPC中可生物可利用NO的降低会导致时钟蛋白BMAL1和PER-2的振动模式的振幅和频率减少，从而导致PAI-1的昼夜节律调节，而ecs和ecs in n no eccc and no ecccs no ecs in no ecs and no ecs and no ecs的丧失损失。 VASA神经中PAI-1的生物利用度没有降低，导致BM神经病的发展，这导致EPC动员有缺陷，进一步加剧了最终器官的并发症。为了检验我们的假设，我们提出以下目的：1）确定无生物利用度是否会影响血管ECS和BMPC中的分子时钟和昼夜节律的分子节奏，并确定NO水平是否会直接和间接对时钟基因表达对BMAL1和PER-2和PER-2和PER-2和PER-2和PER-2和PER-2和PER-2; 2）确定内皮和BMPC的特定时钟基因敲除是否概括了加速损伤和修复减少的糖尿病血管表型； 3）确定在VASA神经内NO和PAI-1的失调是否导致BM神经病以及BMPC散发出循环中的昼夜节律丧失。公共卫生相关性：该提案代表了我们对糖尿病微血管并发症发病机理的理解的范式转变。我们正在测试昼夜节律振荡器是否在内皮细胞和骨髓祖细胞稳态中起关键作用。我们认为，当糖尿病中破坏时，必须在实现血管健康之前恢复它们。我们特异性地识别纤溶酶原激活剂抑制剂是糖尿病中新型的治疗靶标，可恢复血管和骨髓细胞中一氧化氮的血管功能和昼夜节律振荡。