Harnessing the Adaptive ER Stress Response in Myocardial Ischemia

利用适应性 ER 应激反应治疗心肌缺血

• 批准号: 10227351
• 负责人: Chris Glembotski
• 金额: $ 34.99万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10227351
• 关键词: ATF6 gene; Address; Apoptosis; Binding; Calcium; Cardiac; Cardiac Myocytes; Cell Nucleus; Cessation of life; Coupled; Data; Disease; Dose; Endoplasmic Reticulum; Environment; Exhibits; Fostering; Gene Deletion; Gene Transfer; Genes; Genetic Transcription; Goals; Growth Factor; Heart; Heart failure; Heat shock proteins; Hela Cells; Hormone Receptor; Hypoxia; Infarction; Ion Channel; Ischemia; Knockout Mice; Mediating; Mission; Modeling; Molecular; Monitor; Morbidity - disease rate; Mus; Muscle Cells; Mutation; Myocardial Infarction; Myocardial Ischemia; Myocardial dysfunction; Normal Cell; Preparation; Process; Property; Proteins; Public Health; Quality Control; Recovery; Regulation; Research; Response Elements; Signal Transduction; Signaling Protein; Site; Structure; Testing; Therapeutic; Time; United States National Institutes of Health; Wild Type Mouse; base; biological adaptation to stress; cancer cell; cell type; design; effective therapy; endoplasmic reticulum stress; gain of function; heart function; improved; in vivo; innovation; mortality; myocardial damage; neoplastic cell; novel; novel strategies; novel therapeutics; overexpression; protein folding; protein misfolding; small molecule; transcription factor; tumor

Project Summary Myocardial ischemia causes ER stress and potentially lethal ER protein misfolding. The adaptive ER stress response restores ER protein folding and fosters myocyte survival. If this process is not sufficient to restore ER protein folding, the ensuing maladaptive ER stress response leads to myocyte death. To survive the hypoxic environment in tumors, cancer cells have evolved an exaggerated adaptive ER stress response, mediated partly by the transcription factor, ATF6, which is activated by ER stress. Compared to cancer cells, normal cells have relatively little ATF6 and a weak adaptive ER stress response. Our preliminary data showed that ATF6 deletion increased infarct size and decreased function in mouse hearts subjected to myocardial infarction. The objective of the proposed research is to examine the molecular mechanism of ATF6 function in the heart, which will reveal new information needed to develop novel therapies for ischemic heart disease based on harnessing the adaptive ER stress response in the heart. In our previous studies, we were surprised to find that activated ATF6 is rapidly degraded; this degraded-when-active property suggests that strict regulation of the level of ATF6 and the genes it regulates, must have functional significance; however, this significance has not been examined. Our hypotheses are as follows: 1- Endogenous ATF6 adaptively decreases apoptosis and infarct size upon ischemia, which improves post-ischemia myocardial recovery. 2- ATF6 is degraded when active because short-term ATF6 activation is adaptive, while long-term ATF6 activation is maladaptive. 3- Activation of endogenous ATF6 with small molecule activators is adaptive, and because it is reversible, we can regulate dose and time to maximize adaptive and minimize maladaptive effects of ATF6 activation to optimize therapeutic potential. These three hypotheses will be addressed by the following corresponding Specific Aims: 1- To assess the effects of endogenous ATF6 deletion on cardiac structure and function in an MI model of heart failure using ATF6 knockout (KO) mice. 2- To use AAV9-mediated gene transfer of forms of ATF6 that exhibit a range of degraded-when-active properties into ATF6 KO mice, then assess the effects of these forms of ATF6 on cardiac structure and function in an MI model of heart failure. 3- To determine the effects of novel small molecule activators of endogenous ATF6 on the viability and on ER stress signaling, initially in isolated cardiac myocytes and then and in mice, in vivo.

项目摘要 心肌缺血会引起ER应力，并可能导致致命的ER蛋白质折叠。自适应ER应力 反应恢复ER蛋白折叠并促进肌细胞的存活。如果此过程不足以恢复ER 蛋白质折叠，随之而来的适应不良的ER应力反应导致肌细胞死亡。生存低氧 肿瘤的环境，癌细胞已经发展出夸张的适应性ER应激反应，介导 部分由转录因子ATF6，该因子被ER应力激活。与癌细胞相比，正常细胞 ATF6相对较少，自适应ER应力反应较弱。我们的初步数据表明ATF6 缺失增加了梗塞大小和降低受心肌梗塞的小鼠心脏的功能。这 拟议的研究的目的是检查心脏中ATF6功能的分子机制， 这将揭示基于缺血性心脏病的新疗法所需的新信息 利用心脏的适应性ER应力反应。在我们以前的研究中，我们惊讶地发现 激活的ATF6迅速降解；当活性属性时，这种退化 ATF6的水平及其调节的基因必须具有功能意义。但是，这种意义具有 没有被检查。我们的假设如下：1-内源性ATF6适应降低凋亡和 缺血时梗死大小，改善了心肌恢复后的心肌恢复。 2- atf6在 活跃，因为短期ATF6激活是适应性的，而长期ATF6激活是适应不良的。 3- 用小分子激活剂激活内源性ATF6是自适应的，由于它是可逆的，我们可以 调节剂量和时间以最大化适应性并最大程度地减少ATF6激活的不良适应作用以优化 治疗潜力。这三个假设将通过以下相应的特定目的来解决： 1-评估内源性ATF6缺失对心脏结构和功能的影响 使用ATF6敲除（KO）小鼠的心力衰竭。 2-使用AAV9介导的基因转移的ATF6形式的基因转移 当激活特性中的一系列降解性特性向ATF6 KO小鼠展示，然后评估这些形式的效果 在心力衰竭的MI模型中，ATF6的心脏结构和功能。 3-确定新颖的影响 内源性ATF6在生存力和ER应力信号传导上的小分子激活剂，最初是在分离的 心肌细胞，然后在小鼠中，体内。

项目成果

Optimization of Large-Scale Adeno-Associated Virus (AAV) Production.

大规模腺相关病毒 (AAV) 生产的优化。

• DOI: 10.1002/cpz1.757
• 发表时间: 2023
• 期刊: Current protocols
• 作者: Bilal,AlinaS;Parker,SarahN;Murray,VictoriaB;MacDonnell,LaurenF;Thuerauf,DonnaJ;Glembotski,ChristopherC;Blackwood,ErikA
• 通讯作者: Blackwood,ErikA