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.

项目摘要 肝硬化相关死亡是美国的主要死亡原因之一，酒精性脂肪肝（AFLD）占 造成了48%的死亡。尽管AFLD对健康和经济影响深远，但其管理仍是一个具有挑战性的前景 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， 进展为更严重的临床病症，以及（ii）在过去四十年中没有开发新的治疗实体。的 本研究项目的长期目标是阐明氧化还原相关的机制参与保护肝脏免受AFLD 从而鉴定针对该疾病的潜在的新的预防和/或治疗靶点。氧化应激在 许多途径参与了AFLD的发病机制。促进氧化应激发展的主要因素是 谷胱甘肽（GSH），肝脏中最丰富的非蛋白硫醇耗尽。我们使用GCLM敲除（KO）的初步研究 小鼠证明，肝脏GSH约85%的缺乏使小鼠免受慢性乙醇诱导的脂肪变性的影响， 局这些小鼠还表现出：（i）代谢乙醇和乙醛的能力增强，（ii）持续的氧化应激 和诱导核因子-红细胞2-相关因子2（NRF 2）靶基因，和（iii）重要的是，持续激活AMP-2， 活化的蛋白激酶（AMPK）途径和相关的脂质代谢基因的变化。该研究项目将利用 GCLM KO模型，以扩大我们的初步研究，并调查我们的工作假设，慢性GSH耗竭诱导 AMPK通路的氧化还原激活，AMPK通路作为触发预防AFLD的保护机制的中心环节。我们提出 阐明KO肝细胞中维持AMPK活化的氧化还原相关机制，鉴定AMPK催化亚基亚型- KO肝细胞中参与乙醇相关代谢和应激反应的依赖性途径，并确定其贡献 GSH缺乏在调节AMPK通路和KO小鼠的保护表型中的肝与肝外效应的比较。的 这些研究的结果将提供重要的机制信息，涉及的关键信号和代谢途径， 防止酒精引起的肝损伤。预计这些新的知识将揭示新的治疗靶点， 治疗酒精性肝损伤，如AFLD。这个K 01奖将允许申请人获得先进的知识， 通过跨学科资源的整合酒精研究的研究能力。申请人已提交一份 咨询委员会由一群杰出的导师和顾问组成。Vasilis Vasiliou博士（主要导师）是一位 乙醇代谢和毒性领域公认的领导者。Wajahat Zafar Mehal博士（共同导师）是一位著名的肝病学家， 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。Michael Harris Nathanson博士（合作伙伴） 导师）是耶鲁肝脏中心的主任，是研究肝病信号通路的世界领导者之一。的 该计划将争取博士的专业知识，赵宏宇（顾问），谁是世界领先的应用统计 分子生物学方法。咨询委员会的每个成员都有一个令人敬畏的记录， 独立的科学家，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。