Reductive Stress Induces Proteotoxic Cardiac Disease

还原性压力诱发蛋白毒性心脏病

基本信息

批准号：
8886857
负责人：
Rajasekaran Namakkal Soorappan
金额：
$ 36.5万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-07-29 至 2018-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8886857
关键词：
Age-Months Amyloid Animal Model Antioxidants Apoptotic Area Biochemistry Cardiac Cardiac Myocytes Cardiomyopathies Cardiovascular Diseases Cells Cessation of life Chemicals Chemistry Chronic Clinical Cytoskeletal Proteins Endoplasmic Reticulum Environment Enzymes Equilibrium Erythroid Free Radicals Functional disorder Gene Targeting Genes Genetic Glutathione Goals Health Heart Heart Diseases Heart Hypertrophy Heart failure Heat shock proteins Homeostasis Human Hypertrophy Image In Vitro Knock-out Knowledge Laboratories Lead Mediating Metabolic Modeling Molecular Molecular Chaperones Mus Mutation Myocardial NADP NQO1 gene Nuclear Outcome Study Oxidation-Reduction Oxidative Stress Pathogenesis Pathway interactions Patients Physicians Physiology Process Proteins Quality Control Research Response Elements Scientist Signal Transduction Stress System Testing Therapeutic Therapeutic Intervention Transcript Transgenic Organisms Ubiquitin Ubiquitination base catalase constriction endoplasmic reticulum stress experience gene therapy improved in vivo knock-down mitochondrial dysfunction mouse model multicatalytic endopeptidase complex next generation prevent protein aggregation protein folding protein function research study response stress protein

项目摘要

DESCRIPTION (provided by applicant): The significance and pathogenic consequences of proteotoxicity and proteinopathy in failing hearts have received recent clinical notice. Accumulation of defective proteins and their aggregation impair proteostasis and lead to pathological consequences in cardiomyocytes. A homeostatic balance (proteostasis) between synthesis and degradation of defective proteins is crucial for the dynamically active cardiomyocytes. Mounting evidence indicates that a majority of protein aggregation cardiomyopathies (PAC) caused by mutations in cytoskeletal proteins or chaperones involve pre-amyloid aggregates, oxidative stress, mitochondrial dysfunction and apoptotic death of cardiomyocytes. We now demonstrate that constitutive activation of nuclear erythroid-2 like factor-2 (Nrf2) signaling is a potential mechanism for Reductive Stress (RS) and PAC in these pathogenic processes. Our findings pinpoint RS as the metabolic insult responsible for pathogenesis in human cardiac disease. Our long-term goal is to investigate the molecular mechanisms for RS mediated proteotoxic cardiac disease and explore relevant therapeutic interventions. We hypothesize that abnormal increases in intracellular reducing power contributes to RS, which will cause proteotoxic cardiac remodeling and dysfunction through impaired protein quality control mechanisms. Accordingly, we propose the following aims: (1) To determine whether chronic reductive stress (CRS) is sufficient to cause cardiac hypertrophy and pathological remodeling, (2) To determine whether CRS impairs endoplasmic reticulum (ER) and ubiquitin- proteasome function to promote proteotoxicity and protein aggregation and (3) To determine whether preventing RS or preserving ER function rescues the CaNrf2-TG mice from proteotoxic cardiac remodeling and dysfunction. To study these aims, we have established mouse models for RS by constitutively activating Nrf2 (CaNrf2) in the heart [CaNrf2-TG or Keap1-/-:aMHC-Cre-TG (cardiomyocyte-specific constitutive activation of Nrf2 signaling)]. First, we will determine the effects of RS on cardiac function, structural remodeling and stress- induced cardiac hypertrophy in mice with trans-aortic constriction. Next, we will study the effect of RS on redox potential of ER and investigate the mechanisms associated with ER stress and unfolded protein response pathways in the CaNrf2-TG or Keap1-/-:aMHC-CreTG mice with proteotoxic cardiac disease. Then, we will use pharmacological approaches to prevent RS or ER stress to rescue the proteotoxic cardiac disease. Alternatively, we will use genetic approaches to knock down Nrf2 to prevent RS and resultant proteotoxicity. A team of scientists and physicians with relevant experience in cardiac physiology, cardiac imaging, free-radical chemistry, biochemistry, molecular biology and gene therapy will be involved in this project. The proposal also includes a strong plan for educating the next generation (undergraduates and postgraduates) with cutting-edge research. The overall outcome of this study will yield new knowledge on RS and proteotoxic effects in the heart, which will likely enhance therapeutic applications in human patients in the next 5-6 years.

描述（由申请人提供）：蛋白质毒性和蛋白质病在失败的心脏中的显着性和致病后果已收到最近的临床通知。有缺陷蛋白的积累及其聚集会损害蛋白质的蛋白质，并导致心肌细胞的病理后果。合成和有缺陷蛋白质降解之间的稳态平衡（蛋白抑制剂）对于动态活性的心肌细胞至关重要。越来越多的证据表明，大多数蛋白质聚集心肌病（PAC）（PAC）是由细胞骨架蛋白或伴侣伴侣突变引起的，涉及淀粉样蛋白的聚集体，氧化应激，线粒体功能障碍和心肌细胞的凋亡死亡。我们现在证明，在这些致病过程中，核红细胞-2（NRF2）信号的组成型激活是还原应力（RS）和PAC的潜在机制。我们的发现将RS指定为负责人心脏病发病机理的代谢损伤。我们的长期目标是研究RS介导的蛋白毒性心脏病的分子机制，并探索相关的治疗干预措施。我们假设细胞内还原功率异常增加会导致RS，这将通过受损的蛋白质质量控制机制引起蛋白质毒性心脏重塑和功能障碍。 Accordingly, we propose the following aims: (1) To determine whether chronic reductive stress (CRS) is sufficient to cause cardiac hypertrophy and pathological remodeling, (2) To determine whether CRS impairs endoplasmic reticulum (ER) and ubiquitin- proteasome function to promote proteotoxicity and protein aggregation and (3) To determine whether preventing RS or preserving ER function rescues the CaNrf2-TG来自蛋白质毒性心脏重塑和功能障碍的小鼠。为了研究这些目标，我们通过在心脏[CANRF2-TG或KEAP1 - / - ：AMHC-CRE-TG（心肌细胞特异性的NRF2信号的构成本构型激活）中的组成性激活NRF2（CANRF2）来建立了RS的小鼠模型。首先，我们将确定RS对具有反应式收缩的小鼠中心脏功能，结构重塑和应激诱导的心脏肥大的影响。接下来，我们将研究RS对ER的氧化还原电位的影响，并研究与CanRF2-TG或KEAP1-/ - ：AMHC-Cretg小鼠患有蛋白质毒性心脏病的CANRF2-TG或KEAP1-/ - ：AMHC-CRETG相关的机制。然后，我们将使用药理学方法来防止RS或ER压力来挽救蛋白质毒性心脏病。另外，我们将使用遗传方法击倒NRF2，以防止Rs和由此产生的蛋白质毒性。该项目将涉及一支具有心脏生理学，心脏成像，自由基化学，生物化学，分子生物学和基因疗法的科学家和医生团队。该提案还包括一个强大的计划，以对下一代（本科生和研究生）进行最先进的研究。这项研究的总体结果将在心脏中产生有关RS和蛋白毒性作用的新知识，这可能会在未来5 - 6年内增强人类患者的治疗应用。