S-nitrosation in cell survival and cell death

项目总结 心肌缺血再灌注损伤是美国男性和女性死亡的主要原因 各州。心脏保护机制有望减轻这一负担，但很少有实验发现 已经成功地转化为有效的疗法。一氧化氮，内源性产生或给药 外源性，已被确定为许多不同心脏保护途径的重要组成部分。我们的 最近的研究结果表明，半胱氨酸硫醇的S亚硝化(SNO)是一氧化氮依赖所必需的。 女性心脏的保护，表现出比男性更高的基线SNO水平，并与 这样，对缺血再灌注损伤有更好的保护作用。一氧化氮水平受S-亚硝基谷胱甘肽的调节 还原酶(GSNOR)，分解蛋白质SNO，我们有证据表明GSNOR是一个关键 心中保护的中介人。我们还确定了另外两个靶点(TRIM72，线粒体 蛋白质)对SNO介导的男性和女性心脏的缺血应激反应至关重要，但具有特异性 减少细胞死亡和潜在的性别差异的机制尚不清楚。因此，一个重要的 在一些与生理和心理问题有关的基本问题上存在着知识差距 SNO信号在男女心脏中的病理生理作用(S)。为了解决这一知识鸿沟，我们有 开发了许多新的方法来鉴定和定量特定的原位SNO修饰 位于中心的地点。在目前的应用中，我们建议将这些方法与体内和EX一起使用 心肌缺血再灌注损伤的活体模型以及新开发和新兴的方法学，如 哺乳动物(Silam)体内氨基酸稳定同位素标记评估蛋白质周转率、定量质量 光谱分析和代谢组学分析。这些方法将被用来增强我们的机械性 通过以下特定目的理解SNO信号在性别依赖性心脏保护中的作用：1)确定 TRIM72作为SNO保护靶点在缺血再灌注损伤中的作用：2)确定其保护作用 SNO修饰的线粒体蛋白在缺血再灌注损伤中的作用，以及3)确定GSNOR在 减轻缺血再灌注损伤中的亚硝化性应激。如果成功完成，这一计划的目标是 该提议将促进我们对心肌缺血中蛋白质SNO信号的机制的理解- 再灌注损伤与心脏保护。这些研究还将提供宝贵的洞察，以了解基于SNO的 无论是男性还是女性，治疗缺血性心脏病的方法都可能是有针对性的。

PROJECT SUMMARY Myocardial ischemia-reperfusion injury is a leading cause of death in both males and females in the United States. Cardioprotective mechanisms hold promise for lessening this burden, but few experimental discoveries have translated successfully into effective therapeutics. Nitric oxide, produced endogenously or administered exogenously, has been identified as an essential component of many different cardioprotective pathways. Our recent findings suggest that the S-nitrosation (SNO) of cysteine thiols is essential for nitric oxide-dependent protection in female hearts, which exhibit higher baseline SNO levels compared to males and associated with this, greater protection from ischemia-reperfusion injury. SNO levels are regulated by S-nitrosoglutathione reductase (GSNOR), which catabolizes protein SNO, and we have evidence to suggest that GSNOR is a key mediator of protection in the heart. We have also identified two additional targets (TRIM72, mitochondrial proteins) that are critical for the SNO-mediated ischemic stress response in male and female hearts, but specific mechanisms for reducing cell death and potential sex differences are not known. As such, a significant knowledge gap exists regarding a number of fundamental questions related to the physiological and pathophysiological role(s) of SNO signaling in male and female hearts. To address this knowledge gap, we have developed a number of novel methods for the identification and quantitation of specific in situ SNO modification sites in the heart. In the present application, we propose to use these methods in tandem with in vivo and ex vivo models of myocardial ischemia-reperfusion injury and newly developed and emerging methodologies, like in vivo stable isotope labeling by amino acids in mammals (SILAM) to assess protein turnover, quantitative mass spectrometry, and metabolomics analysis. These approaches will be used to enhance our mechanistic understanding of SNO signaling in sex-dependent cardioprotection through the following specific aims: 1) define the role of TRIM72 as a protective target of SNO during ischemia-reperfusion injury, 2) define the protective role of SNO-modified mitochondrial proteins during ischemia-reperfusion injury, and 3) define the role of GSNOR in mitigating nitrosative stress during ischemia-reperfusion injury. If completed successfully, the aims of this proposal will advance our mechanistic understanding of protein SNO signaling in myocardial ischemia- reperfusion injury and cardioprotection. These studies will also provide valuable insight into how SNO-based approaches may be targeted for the therapeutic treatment of ischemic heart disease in both males and females.