Mechanisms of intracellular NAMPT-regulated GSNOR in vessel wall

细胞内NAMPT调节血管壁GSNOR的机制

基本信息

批准号：
8278792
负责人：
Adam Carl Straub
金额：
$ 9万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-06-15 至 2013-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8278792
关键词：
Anabolism Arteries Attenuated Blood Pressure Blood Vessels Cardiovascular Diseases Cell Signaling Process Cells Coculture Techniques Communication Connexin 43 Connexins Coupling Cysteine Electrons Elements Endothelial Cells Endothelium Enzymes Equilibrium Excision Figs - dietary Functional disorder Future Gap Junctions Grant Hypertension In Vitro Lead Measures Mediating Modeling Modification Molecular Mus Niacinamide Nicotinamide adenine dinucleotide Nitric Oxide Oxidoreductase Pathway interactions Peptides Permeability Pilot Projects Play Post-Translational Protein Processing Process Proteins Proteomics Recombinants Regulation Resistance Role S-Nitrosoglutathione Side Smooth Muscle Smooth Muscle Myocytes Sulfhydryl Compounds Testing Time Vascular Endothelial Cell Vascular Smooth Muscle Vascular resistance Vasoconstrictor Agents Vasodilator Agents Work abstracting base blood pressure regulation cell type constriction human NOS3 protein hypertension treatment inhibitor/antagonist interest protein expression protein protein interaction response trafficking vasoconstriction

项目摘要

DESCRIPTION (provided by applicant): Abstract The regulation of resistance arterial tone involves communication between vascular smooth muscle and endothelium, which is tightly controlled by an intricate, but yet to be fully defined, cell signaling processes. Recently, we made the discovery that S-nitrosylation/denitrosylation, the addition or removal of a nitric oxide group from a cysteine-thiol side chain, serves as an important post-translational modification on connexin 43 gap junction (GJ) proteins, and that this modification is associated with control of resistance arterial tone. Regulation of connexin 43 nitrosylation appeared to be predominant at the myoendothelial junction (MEJ), the point where endothelial cells and smooth muscle cells make contact in resistance arteries. At the MEJ, endothelial nitric oxide synthase (eNOS), and the denitrosylase S-nitrosoglutathione reductase (GSNOR), work in concert to modulate the permeability of GJs. The mechanisms regulating eNOS activity have been well characterized, however the molecular mechanisms regulating GSNOR activity remain poorly understood. To identify enriched proteins at the MEJ capable of regulating GSNOR activity, we recently performed an in vitro MEJ proteomic screen. From this analysis, we found enriched expression of nicotinamide phoshoribosyltransferase (NAMPT), a rate-limiting enzyme in the nicotinamide adenine dinucleotide (NAD) biosynthesis pathway. The localized protein expression of intracellular NAMPT at the MEJ suggested to us that it is critical for the regulation of NAD levels which are known to modulate GSNOR activity and thus might control heterocellular communication in the vessel wall. In our pilot studies, we explored key elements of this concept by showing that intracellular NAMPT can regulate GSNOR activity and resistance arterial tone. Based on these observations we formulated the central hypothesis that vascular resistance and thus, systemic blood pressure control is mediated through a localized NAMPT-regulated GSNOR mechanism. We will test this hypothesis using three specific aims: AIM 1 will test whether NAMPT regulates GSNOR activity and heterocellular communication in vitro, AIM 2 will determine if NAMPT is critical in the regulation of resistance arterial tone, AIM 3 will elucidate how cell-type specific modulation of NAMPT expression in endothelium or smooth muscle modifies the responses to vasoconstrictors or vasodilators in resistance arteries. Our results will impact our understanding of these enzymes in blood pressure control and provide a framework to determine whether dysfunctions in the expression and/or activity of NAMPT and GSNOR contribute to cardiovascular diseases including hypertension.

描述（由申请人提供）：摘要对电阻动脉音调的调节涉及血管平滑肌和内皮之间的通信，这是由复杂但尚未完全定义的细胞信号传导过程紧密控制的。最近，我们发现了S-亚硝基化/硝基糖基化，从半胱氨酸 - 硫醇侧链中添加或去除一氧化氮基团，是对连接蛋白43 GAP连接（GJ）蛋白质的重要后翻译后修饰，并且这种修饰与控制的控制抗性相关。连接43硝基化的调节似乎在肌膜内皮结（MEJ）中占主导地位，内皮细胞和平滑肌细胞在抗性动脉中接触。在MEJ，内皮一氧化氮合酶（eNOS）和脱硝基糖基酶S-硝基戊二酸还原酶（GSNOR）共同调节GJS的通透性。调节eNOS活性的机制已得到很好的特征，但是调节GSNOR活性的分子机制仍然很少了解。为了鉴定能够调节GSNOR活性的MEJ的富集蛋白，我们最近进行了一项体外MEJ蛋白质组学筛选。从该分析中，我们发现了烟酰胺phoshoribosylysylansferase（NAMPT）的富集表达，这是烟酰胺腺嘌呤二核苷酸（NAD）生物合成途径中的速率限制酶。细胞内NAMPT在MEJ上的局部蛋白表达向我们表明，这对于调节NAD水平的调节至关重要，NAD水平已知会调节GSNOR活性，因此可能控制血管壁中的杂细胞通信。在我们的试点研究中，我们通过表明细胞内NAMPT可以调节GSNOR活性和抗药性动脉张力来探讨该概念的关键要素。基于这些观察结果，我们制定了一个中心假设，即血管阻力及其通过局部NAMPT调节的GSNOR机制介导全身性血压控制。 We will test this hypothesis using three specific aims: AIM 1 will test whether NAMPT regulates GSNOR activity and heterocellular communication in vitro, AIM 2 will determine if NAMPT is critical in the regulation of resistance arterial tone, AIM 3 will elucidate how cell-type specific modulation of NAMPT expression in endothelium or smooth muscle modifies the responses to vasoconstrictors or vasodilators in resistance arteries.我们的结果将会在血压控制中影响我们对这些酶的理解，并提供一个框架，以确定NAMPT和GSNOR表达和/或活性中功能障碍是否有助于包括高血压在内的心血管疾病。