Cardioprotective Mechanisms of Glutathione S-transferase P

谷胱甘肽 S-转移酶 P 的心脏保护机制

基本信息

批准号：
7838943
负责人：
Daniel Joseph Conklin
金额：
$ 23.55万
依托单位：
UNIVERSITY OF LOUISVILLE
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-07-15 至 2012-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7838943
关键词：
Ablation Accounting Acrolein Acute Affect Affinity Aldehydes Antioxidants Attenuated Biochemical Pathway Cardiac Cardiac Myocytes Cardiovascular Physiology Cardiovascular system Coronary Occlusions Coronary heart disease Doctor of Philosophy Drug Metabolic Detoxication Drug resistance Enzymes Epidemiology Excision Foundations Future Gender Genes Genetic Genetic Polymorphism Glutathione Glutathione S-Transferase Heart Human In Situ Individual Infarction Injury Intervention Ischemia Kinetics Knockout Mice Lead Link Lipid Peroxidation MAPK8 gene Measures Mediating Metabolic Metabolic Pathway Metabolism Modeling Mus Myocardial Myocardial Infarction Myocardial Ischemia Natural regeneration Oxidative Stress Pathology Pathway interactions Peroxidases Peroxides Phenotype Population Post-Translational Protein Processing Predisposition Principal Investigator Production Protein Isoforms Proteins Race Reactive Oxygen Species Reduced Glutathione Relative (related person)Reperfusion Injury Reperfusion Therapy Research Role Signal Pathway Signal Transduction Stress Sulfenic Acids Testing Tissues Tracer Transgenic Mice Transgenic Organisms Translations adduct base carcinogenesis cardiovascular disorder risk detoxication enzyme substrate gain of function heart metabolism insight loss of function novel overexpression oxidative damage oxidized lipid prevent programs protein protein interaction public health relevance translational study

项目摘要

DESCRIPTION (provided by applicant): The glutathione S-transferases (GSTs) are a superfamily of ubiquitously expressed enzymes that conjugate reduced glutathione (GSH) with toxic electrophiles. The GST isoforms have also been show to regulate ASK-1 and JNK activation via protein-protein interactions. In human populations, the GST isoforms are distributed in a race- and gender-specific manner. The GSTs are expressed in cardiovascular tissues, but the role of GST in cardiovascular physiology and pathology has not been studied. We propose that GSTP, the most abundant cardiac isoform, is an essential component of myocardial defense against oxidative stress and it protects the heart from acute oxidative damage during ischemia-reperfusion (I/R). To test this hypothesis, we will assess the contribution of GSTP to cardiac protection during I/R in situ (Aim 1), metabolism of lipid peroxidation- derived aldehydes (acrolein and 4-hydroxy-trans-2-nonenal; HNE), which are the preferred endogenous substrates of this enzyme (Aim 2), and aldehyde detoxication (Aim 3). As a loss of function test, GSTP-null mice will be exposed to I/R, while in gain of function tests, transgenic (TG) and TG mice crossed with null mice with cardiac-restricted expression of human polymorphic GSTP1-1 genes will be exposed to I/R and infarction determined. Using tracer kinetics and mass spectrometric analysis, we will measure the extent to which glutathiolation accounts for the metabolism of these aldehydes before, during and after ischemia in the heart (Aim 2). To delineate the contribution of GSTP, we will compare metabolic pathways, including aldehyde conjugation and peroxidase activity, in hearts isolated of GSTP WT, null, and TG mice. In Aim 3, we will determine whether GSTP protects the heart from I/R-induced injury by increasing glutathione conjugation of aldehydes, decreasing aldehyde formation, decreasing aldehyde-protein adducts, decreasing peroxide formation, decreasing oxidative post-translation protein modifications (e.g., sulfenic acid) by glutathiolation, and protecting myocardial GSH level. In addition, we will determine if GSTP regulates JNK activation and JNK signaling thereby investigating a non-catalytic role of GSTP in protein-protein interactions. Successful completion of these studies may lead to the identification of a novel mechanism of cardioprotection by GSTP, which may be useful in assessing the relative ischemic susceptibility of human populations polymorphic in GSTP and in developing more targeted anti-ischemic interventions. PUBLIC HEALTH RELEVANCE The glutathione S-transferases (GSTs) are widely expressed enzymes that detoxify reactive compounds. In human populations, the GSTs are distributed in a race- and gender-specific manner, and GST polymorphisms are associated with increased cardiovascular disease risk. This study will assess if GSTP is an essential component of myocardial defense against injury of heart attacks. Successful completion of these studies may lead to the identification of a novel mechanism of cardioprotection by GSTP, which may be useful in understanding the relative susceptibility of human populations polymorphic in GSTP to coronary heart disease and in developing more targeted cardioprotective interventions.

描述（由申请人提供）：谷胱甘肽 S-转移酶 (GST) 是一个普遍表达的酶超家族，可将还原型谷胱甘肽 (GSH) 与有毒亲电子试剂结合。 GST 亚型还被证明可以通过蛋白质-蛋白质相互作用调节 ASK-1 和 JNK 激活。在人群中，GST 同工型以种族和性别特异性方式分布。 GST在心血管组织中表达，但GST在心血管生理和病理中的作用尚未研究。我们认为 GSTP 是最丰富的心脏亚型，是心肌防御氧化应激的重要组成部分，它可以保护心脏在缺血再灌注 (I/R) 过程中免受急性氧化损伤。为了检验这一假设，我们将评估 GSTP 在原位 I/R 期间（目标 1）、脂质过氧化衍生醛（丙烯醛和 4-羟基-反式-2-壬烯醛；HNE）代谢期间对心脏保护的贡献，其中是该酶的首选内源底物（目标 2）和醛解毒（目标 3）。作为功能丧失测试，GSTP 缺失小鼠将暴露于 I/R，而在功能获得测试中，转基因 (TG) 和 TG 小鼠与人类多态性 GSTP1-1 基因心脏受限表达的缺失小鼠杂交，将暴露于 I/R。暴露于 I/R 并确定梗塞。使用示踪动力学和质谱分析，我们将测量谷胱甘肽在心脏缺血之前、期间和之后对这些醛类代谢的影响程度（目标 2）。为了描述 GSTP 的贡献，我们将比较 GSTP WT、null 和 TG 小鼠分离心脏中的代谢途径，包括醛缀合和过氧化物酶活性。在目标 3 中，我们将确定 GSTP 是否通过增加醛的谷胱甘肽缀合、减少醛形成、减少醛-蛋白质加合物、减少过氧化物形成、减少氧化翻译后蛋白质修饰（例如，次磺酸）通过谷胱甘肽化作用，保护心肌 GSH 水平。此外，我们将确定 GSTP 是否调节 JNK 激活和 JNK 信号传导，从而研究 GSTP 在蛋白质-蛋白质相互作用中的非催化作用。这些研究的成功完成可能会导致 GSTP 心脏保护的新机制的鉴定，这可能有助于评估 GSTP 多态性人群的相对缺血易感性和开发更有针对性的抗缺血干预措施。公共卫生相关性谷胱甘肽 S-转移酶 (GST) 是广泛表达的酶，可解毒活性化合物。在人群中，GST 以种族和性别特异性方式分布，GST 多态性与心血管疾病风险增加相关。这项研究将评估 GSTP 是否是心肌防御心脏病损伤的重要组成部分。这些研究的成功完成可能会导致确定 GSTP 的心脏保护新机制，这可能有助于了解 GSTP 多态性人群对冠心病的相对易感性，并有助于制定更有针对性的心脏保护干预措施。