Methylarginines and Vascular Injury

本提案的长期目标是建立蛋白质精氨酸甲基转移酶， 二甲基精氨酸二甲基氨基水解酶（DDAH），负责甲基精氨酸的酶 合成和代谢，作为内皮功能的关键调节剂。我们假设 在心血管疾病中观察到的血浆ADMA增加是DDAH活性的生物标志物 许多归因于ADMA的内皮影响直接表现为 DDAH-PRMT活性改变。我们已经表明，除了ADMA对 eNOS活性，DDAH通过ADMA非依赖性调节内皮NO产生 涉及改变蛋白质甲基化和氨基酸代谢的机制。的目标 目前的建议是：1.）鉴定内皮中ADMA代谢的途径; 2.） 确定DDAH调节内皮蛋白精氨酸的机制 甲基化并确定蛋白质甲基化对内皮功能的影响; 3.）确定 DDAH调节血管内皮L-精氨酸代谢的机制， 对内皮NO产生的影响;和4.）确定机制， PRMT-DDAH-ADMA轴调节内皮功能和动脉粥样硬化易感性。中的每 为了实现这些目标，细胞、分子、生物物理和生理学方法的组合将 用于体外和体内表征DDAH对内皮功能的影响 模型这些研究的结果将提供有关以下方面的基本机制信息： PRMT-DDAH-ADMA轴调节细胞功能的机制， 可能会带来治疗血管疾病的新方法。

The long term objective of this proposal is to establish Protein Arginine Methyltransferases and Dimethyarginine Dimethylaminohydrolase (DDAH), the enzymes responsible for methylarginine synthesis and metabolism, as a key regulator of endothelial function. It is our hypothesis that the increased plasma ADMA observed in cardiovascular disease is a biomarker of DDAH activity and that many of the endothelial affects attributed to ADMA are directly manifested through altered DDAH-PRMT activity. We have shown that in addition to the direct effects of ADMA on eNOS activity, DDAH modulates endothelial NO production through ADMA independent mechanisms involving altered protein-methylation and amino acid metabolism. The goals of the current proposal are to: 1.) identify the pathways of ADMA metabolism in the endothelium; 2.) determine the mechanisms through which DDAH modulates endothelial protein-arginine methylation and define the effects of protein methylation on endothelial function; 3.) determine the mechanisms through which DDAH regulates endothelial L-arginine metabolism and the consequences on endothelial NO production; and 4.) identify the mechanisms through which the PRMT-DDAH-ADMA axis regulates endothelial function and atherosusceptibility. For each of these aims, a combination of cellular, molecular, biophysical and physiological approaches will be used to characterize the effects of DDAH on endothelial function using in vitro and in vivo models. Results from these studies will provide fundamental mechanistic information regarding the mechanisms through which the PRMT-DDAH-ADMA axis modulates cellular function and may lead to new approaches to treat vascular disease.