Novel Redox-Associated Mechanisms Preventing Alcoholic Fatty Liver

预防酒精性脂肪肝的新型氧化还原相关机制

• 批准号: 9310228
• 负责人: Ying Chen
• 金额: $ 17.56万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-05 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9310228
• 关键词: 5' -AMP-activated protein kinase; Academic Training; Acetaldehyde; Acetic Acids; Advisory Committees; Alcohol dehydrogenase; Alcoholic Fatty Liver; Alcoholic Liver Diseases; Alcoholic liver damage; Alcohols; Anabolism; Animal Model; Antioxidants; Biochemical; Biological Markers; CYP2E1 gene; Catalytic Domain; Cause of Death; Cessation of life; Chronic; Cirrhosis; Clinical; Competence; Data; Development; Diagnostic; Disease; Drug Kinetics; Drug Metabolic Detoxication; Enzymes; Ethanol; Ethanol Metabolism; Ethanol toxicity; Event; Exhibits; Extrahepatic; Fatty Liver; Fibrosis; Free Radicals; GCLC gene; GCLM gene; Gene Expression; Gene Targeting; Generations; Genes; Glutamate-Cysteine Ligase; Glutathione; Goals; Hepatic; Hepatocyte; Immunologist; Individual; Inflammation; Inflammatory Response; Knock-out; Knockout Mice; Knowledge; Life Style; Link; Lipids; Liver; Liver diseases; Long-Term Effects; Mediating; Mentored Research Scientist Development Award; Mentors; Metabolic; Metabolic Pathway; Metabolic stress; Modeling; Molecular Biology; Mus; Nutritional; Oxidants; Oxidation-Reduction; Oxidative Stress; Oxidative Stress Induction; Pathogenesis; Pathogenicity; Pathway interactions; Phenotype; Play; Predisposition; Preventive; Protein Isoforms; Regulation; Research; Research Personnel; Research Project Grants; Resources; Role; STK11 gene; Scientist; Signal Pathway; Signal Transduction; Small Interfering RNA; Statistical Methods; Steatohepatitis; Stress; Sulfhydryl Compounds; Triglycerides; United States; Up-Regulation; Viral; Wild Type Mouse; alcohol abuse therapy; alcohol exposure; alcohol research; alcohol response; aldehyde dehydrogenases; base; biological adaptation to stress; career; economic impact; experimental study; feeding; health economics; knock-down; lipid metabolism; liver injury; member; mouse model; new therapeutic target; non-alcoholic fatty liver; novel; novel therapeutics; nuclear factor-erythroid 2; overexpression; prevent; problem drinker; programs; response; therapeutic target; tool; upstream kinase

PROJECT SUMMARY Cirrhosis-associated death is one of the leading causes of death in the United States and alcoholic fatty liver disease (AFLD) accounts for 48% of these deaths1. Despite its profound health and economic impact, the management of AFLD remains a challenging prospect because: (i) there are no effective diagnostic tools or biomarkers to assess individual susceptibility to AFLD development or progression to more severe clinical conditions, and (ii) no new therapeutic entities have been developed in the past four decades. The long term goal of this research project is to elucidate the redox-associated mechanisms involved in protecting the liver against AFLD and thereby identify potential novel preventive and/or therapeutic targets against this disease. Oxidative stress plays a central role in many pathways involved in the pathogenesis of AFLD. A major factor contributing to the development of oxidative stress is the depletion of glutathione (GSH), the most abundant non-protein thiol in the liver. Our preliminary studies using GCLM knockout (KO) mice demonstrate that ~85% deficiency in hepatic GSH renders mice protected from steatosis induced by chronic ethanol administration. These mice also exhibit: (i) enhanced capacity to metabolize ethanol and acetaldehyde, (ii) persistent oxidative stress and induction of nuclear factor-erythroid 2–related factor 2 (NRF2) target genes, and (iii) importantly, sustained activation of the AMP- activated protein kinase (AMPK pathway and associated changes in lipid metabolizing genes. This research project will utilize the GCLM KO model to expand upon our preliminary studies and investigate our working hypothesis that chronic GSH depletion induces redox activation of the AMPK pathway that serves as the central link triggering protective mechanisms that prevent AFLD. We propose to: elucidate redox-associated mechanism(s) sustaining AMPK activation in KO hepatocytes, identify AMPK catalytic subunit isoform- dependent pathways involved in ethanol-associated metabolic and stress response in KO hepatocytes, and determine the contribution of hepatic versus extrahepatic effects of GSH deficiency in modulating AMPK pathway and the protective phenotype of KO mice. The findings from these studies will provide important mechanistic information regarding key signaling and metabolic pathways involved in protection against alcohol-induced liver damage. It is anticipated that such new knowledge will reveal novel therapeutic targets for the treatment of alcohol-induced liver injury, such as AFLD. This K01 Award will allow the applicant to acquire advanced knowledge and research competency in alcohol research through an integration of interdisciplinary resources. The applicant has assembled an advisory committee composed of an outstanding group of mentors and consultants. Dr. Vasilis Vasiliou (primary mentor) is a recognized leader in the field of ethanol metabolism and toxicity. Dr. Wajahat Zafar Mehal (co-mentor) is a renowned hepatologist and liver immunologist who has extensive expertise in alcoholic and non-alcoholic fatty liver disease. Dr. Michael Harris Nathanson (co- mentor) is the Director of the Yale Liver Center and is among the world leaders in studying signaling pathways in liver disease. The program will enlist the expertise of Dr. Hongyu Zhao (consultant), who is among the world leaders in the application of statistical methods in molecular biology. Each member of the advisory committee has a formidable record of training academically successful independent scientists and they will mentor the applicant's career and academic development as well as the implementation of proposed experiments.

项目概要 肝硬化相关死亡是美国和酒精性脂肪肝 (AFLD) 死亡的主要原因之一 尽管 AFLD 对健康和经济产生了深远的影响，但 AFLD 的治疗仍然充满挑战。 因为：(i) 没有有效的诊断工具或生物标志物来评估个体对 AFLD 发展的易感性，或 (ii) 在过去四十年中没有开发出新的治疗实体。 该研究项目的长期目标是阐明保护肝脏免受 AFLD 影响的氧化还原相关机制 从而确定针对这种疾病的潜在新预防和/或治疗靶标。氧化应激在其中发挥着核心作用。 AFLD 发病机制涉及多种途径，导致氧化应激发生的一个主要因素是氧化应激。 谷胱甘肽 (GSH) 是肝脏中最丰富的非蛋白质硫醇，我们使用 GCLM 敲除 (KO) 进行初步研究。 小鼠证明，约 85% 的肝脏 GSH 缺乏使小鼠免受慢性乙醇诱导的脂肪变性 这些小鼠还表现出：（i）代谢乙醇和乙醛的能力增强，（ii）持续的氧化应激。 以及核因子-红细胞 2 相关因子 2 (NRF2) 靶基因的诱导，以及 (iii) 重要的是，AMP- 的持续激活 激活蛋白激酶（AMPK 通路以及脂质代谢基因的相关变化。该研究项目将利用 GCLM KO 模型扩展了我们的初步研究并调查了我们的工作假设，即慢性 GSH 耗竭会导致 AMPK 通路的氧化还原激活是触发预防 AFLD 的保护机制的中心环节。 目的：阐明 KO 肝细胞中维持 AMPK 激活的氧化还原相关机制，鉴定 AMPK 催化亚基亚型 KO 肝细胞中涉及乙醇相关代谢和应激反应的依赖途径，并确定其贡献 GSH 缺乏在调节 AMPK 通路和 KO 小鼠保护表型中的肝脏与肝外影响的比较。 这些研究的结果将提供有关关键信号传导和代谢途径的重要机制信息 预计这些新知识将揭示新的治疗靶点。 酒精性肝损伤的治疗，例如 AFLD，该 K01 奖将使申请人能够获得先进的知识和知识。 通过整合跨学科资源，申请人具备了酒精研究的研究能力。 顾问委员会由一群杰出的导师和顾问组成，Dr. Vasilis Vasiliou（主要导师）是一位 Wajahat Zafar Mehal 博士（联合导师）是乙醇代谢和毒性领域公认的领导者，是一位著名的肝病学家和专家。 肝脏免疫学家，在酒精性和非酒精性脂肪肝方面拥有丰富的专业知识。 导师）是耶鲁大学肝脏中心主任，是研究肝病信号通路的世界领先者之一。 该计划将聘请赵宏宇博士（顾问）的专业知识，他是统计应用领域的世界领先者之一 顾问委员会的每位成员都在学术上取得了成功的培训记录。 独立科学家，他们将指导申请人的职业和学术发展以及实施 提出的实验。