Microcystin-LR toxicity in nonalcoholic steatohepatitis

微囊藻毒素-LR 对非酒精性脂肪性肝炎的毒性

• 批准号: 9424932
• 负责人: John Daniel Clarke
• 金额: $ 24.9万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9424932
• 关键词: Acute; Adult; Affect; Animals; Applications Grants; Arizona; Biliary; Carrier Proteins; Categories; Cells; Chronic Kidney Failure; Communication; Computer software; Cyanobacterium; Cyclic Peptides; Cysteine; Data; Development; Development Plans; Diet; Disease; Dreams; Educational Activities; Educational workshop; Enterocytes; Environment; Eutrophication; Excretory function; Exhibits; Exposure to; Face; Faculty; Generations; Genetic; Glutathione; Goals; Grant; Health; Health Sciences; Hepatic; Hepatocyte; Hepatotoxicity; Human; In Vitro; Incidence; Intestines; Intravenous; Journals; Kidney; Kinetics; Knock-out; Knowledge; Lead; Liver; Liver diseases; Measures; Mediating; Membrane; Mentors; Metabolism; Methods; Mind; Modeling; Mus; National Institute of Environmental Health Sciences; OATP Transporters; Oral; Organ; Pathologic; Pathway interactions; Patients; Peer Review; Pharmaceutical Preparations; Pharmacology and Toxicology; Phase; Physiological; Plasma; Population; Populations at Risk; Positioning Attribute; Postdoctoral Fellow; Prevalence; Proximal Kidney Tubules; Publishing; Rattus; Reporting; Research; Research Project Grants; Risk; Risk Assessment; Rodent; Scientist; Series; Single Nucleotide Polymorphism; Societies; Source; System; Technical Expertise; Testing; Tissues; Toxic Environmental Substances; Toxic effect; Toxicant exposure; Toxicokinetics; Toxicology; Toxin; Training; Training Activity; Translating; United States; United States National Institutes of Health; Universities; Water; Work; Writing; Xenobiotic Metabolism; Xenobiotics; absorption; acute toxicity; base; career; career development; climate change; contaminated drinking water; cyanobacterial toxin; cyanoginosin LR; disease phenotype; drinking water; environmental stressor; experimental study; exposed human population; exposure route; falls; gastrointestinal; graduate student; high school; improved; in vivo; nephrotoxicity; non-alcoholic fatty liver; nonalcoholic steatohepatitis; overexpression; population based; post-doctoral training; protein transport; public health relevance; research and development; skills; symposium; undergraduate student; uptake; urinary; waterborne

DESCRIPTION (provided by applicant): This pathway to independence grant application describes the training and career development plan for Dr. John Clarke. Dr. Clarke's immediate career goal is to complete the necessary postdoctoral training in order establish a research project in toxicology that is independent from the work of his post-doctoral advisor, Dr. Nathan Cherrington. This goal is directly tied to the research proposed in the application, since this project takes the liver disease phenotype studied in Dr. Cherrington's group and applies it to exposure and toxicity of an environmental stressor. Dr. Clarke's long-term career goals are to 1) improve human health by advancing our understanding of the interaction between liver disease and environmental toxicant exposure, and 2) become a mentor to subsequent generations of scientists. These immediate and long-term career goals will be accomplished through specific aspects of the training environment and the research project. Dr. Clarke's training plan includes expanding his knowledge and recognition in the field of toxicology, developing new technical expertise, improving his mentoring and communication skills, and improving grant writing skills. In order to increase knowledge and recognition in the field of toxicology Dr. Clarke will participate in educational and training activities available through the NIEHS training grant, the Society of Toxicology, the Pharmacology and Toxicology Department, and the Arizona Health Sciences Center. These include seminars, journal clubs, colloquia, and conferences. Dr. Clarke has assembled a "dream team" of mentors and collaborators that will be an incredible asset for his career development and research plan. Dr. Clarke will develop new technical expertise in xenobiotic transport kinetics, in vivo toxicokinetics analyses, organ specific toxicity, and physiologically based toxicokinetics modeling (PBTK). An important aspect of being an independent scientist is the ability to mentor and communicate effectively. As part of the training environment Dr. Clarke will continue to present data at conferences and publish in peer-reviewed journals. He will also continue to mentor high school, graduate, and undergraduate students in Dr. Cherrington's lab. Finally, he will improve his grant writing skills by participatig in a series of grant writing workshops offered at the University of Arizona and through the NIH. By implementing each aspect of this training plan, Dr. Clarke will receive the additional training he needs to successfully transition into an independent faculty position in toxicology. This research project seeks to understand how the liver disease nonalcoholic steatohepatitis (NASH) alters the toxicokinetics and toxicity of the waterborne toxin microcystin-LR (MCLR). The prevalence of NASH, which is the most severe form of nonalcoholic fatty liver disease, continues to increase worldwide and is estimated to be present in 5% to 17% of adults in the United States. In addition to the liver problems this population faces, there is also a higher incidence of chronic kidney disease among these patients, which may be associated with MCLR exposure. MCLR-producing cyanobacteria are ubiquitous in sources of drinking water around the world, and the occurrence of blooms and MCLR contaminated drinking water are expected to increase as anthropomorphic eutrophication of water systems and global climate change continue to worsen. Unfortunately, there is a dearth of information regarding MCLR toxicokinetics in humans and how NASH-associated changes in xenobiotic transporter expression influence MCLR toxicokinetics and MCLR-induced toxicity. The objectives of this research are to 1) provide a complete picture of the xenobiotic transporters responsible for the disposition of MCLR and its main metabolites, MCLR-glutathione and MCLR-cysteine, 2) determine how altered expression of these transporters in NASH affects MCLR disposition and toxicity, and 3) move these findings towards risk assessment by constructing a PBTK model for human MCLR exposure in healthy and NASH populations. Dr. Clarke's previous work has demonstrated that NASH causes decreased expression of the liver uptake transporters important for MCLR-induced liver toxicity: organic anion transporting polypeptide-1b2 (Oatp1b2) in rodents and OATP1B1 and OATP1B3 in humans. He has also shown that this NASH-induced decrease in rodent Oatp1b2 shifted the disposition of several drugs that are substrates for OATPs away from liver exposure towards kidney exposure. In the case of MCLR, it has been shown that genetic knockout of Oatp1b2 completely protected the mice from MCLR-induced liver toxicity. In a recently completed preliminary study Dr. Clarke has shown that MCLR exposure in NASH dramatically increase kidney toxicity compared to healthy controls exposed to MCLR. These data lead to the central hypothesis that people with NASH are at increased risk of altered MCLR exposure and MCLR-induced renal toxicity due to changes in hepatic OATP transporters. To test this hypothesis and achieve the objectives of this project several methods will be employed. First, in vitro transporter kinetics experiments will be performed to identify transporters, beyond the Oatps, that contribute to MCLR disposition. Second, the effect of NASH on MCLR disposition will be determined by measuring toxicokinetics profiles after oral and intravenous MCLR administration in healthy and NASH rats. Third, acute and sub-chronic, sub-lethal toxicity studies will be performed to determine if MCLR exposure in NASH increases renal toxicity. Lastly, a PBTK model for MCLR exposure in humans will be constructed using the Simcyp software to help translate this work into exposure information for human populations. The research project outlined here is important to the development of Dr. Clarke's career but, more importantly, it is important to millions of people worldwide who have NASH and are exposed to MCLR.

描述（由申请人提供）：独立赠款申请的这一途径描述了约翰·克拉克博士的培训和职业发展计划。克拉克博士的直接职业目标是完成必要的博士后培训，以建立一个毒理学研究项目，该项目与他的博士后顾问Nathan Cherrington博士的工作无关。该目标与应用程序中提出的研究直接相关，因为该项目将Cherrington博士小组中研究的肝病表型采用，并将其应用于环境压力源的暴露和毒性。克拉克博士的长期职业目标是1）通过促进我们对肝病和环境有毒物质暴露之间相互作用的了解，改善人类健康，以及2）成为后来的科学家的导师。这些直接和长期的职业目标将通过培训环境和研究项目的特定方面实现。克拉克博士的培训计划包括扩大他在毒理学领域的知识和认可，发展新的技术专长，提高他的指导和沟通能力以及提高赠款写作技巧。为了提高毒理学领域的知识和认可，克拉克博士将通过NIEHS培训补助金，毒理学学会，药理学和毒理学部门以及亚利桑那州健康科学中心参加教育和培训活动。这些包括研讨会，期刊俱乐部，口腔和会议。克拉克博士召集了一个由导师和合作者组成的“梦想团队”，这将是他的职业发展和研究计划的不可思议的资产。 Clarke博士将开发新的技术专业知识，用于异生物传输动力学，体内毒性分析，器官特异性毒性和基于生理的毒素模型（PBTK）。成为独立科学家的一个重要方面是能够有效指导和沟通的能力。作为培训的一部分 环境克拉克博士将继续在会议上介绍数据，并在同行评审期刊上发布。他还将继续在Cherrington博士的实验室指导高中，毕业生和本科生。最后，他将在亚利桑那大学和NIH提供的一系列赠款写作讲习班中提高参与者的赠款写作技巧。通过实施本培训计划的各个方面，克拉克博士将获得他成功地过渡到毒理学独立教师所需的额外培训。该研究项目旨在了解肝病非酒精性脂肪性肝炎（NASH）如何改变水寄水毒素微囊蛋白藻（MCLR）的毒性和毒性。纳什（Nash）的患病率是最严重的非酒精性脂肪肝疾病的形式，在全球范围内继续增加，据估计在美国的成年人中有5％至17％的成年人存在。除了肝脏问题外，这些人群面临的问题还较高，这些患者的慢性肾脏疾病发病率可能与MCLR暴露有关。产生MCLR的蓝细菌在世界各地的饮用水来源中无处不在，随着拟人化水系统和全球气候变化的拟人化富裕性，盛开和MCLR污染的饮用水的发生预计将增加。不幸的是，关于人类中MCLR毒性的信息缺乏信息，以及异种生物转运蛋白表达的变化如何影响MCLR毒素和MCLR诱导的毒性。这项研究的目的是1）提供了负责在MCLR处置及其主要代谢产物MCLR-GLUTATHIONE和MCLR-结合症的型异种生物转运蛋白的完整图片，2）确定这些转运蛋白在NASH中的表达改变如何改变MCLR的构建和3）对人类的构建和3）的构建，以及3）在构建中，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MECL，以及3）MELCL，以及3）MECL，以及3）纳什人。克拉克博士先前的工作表明，NASH会导致肝脏摄取转运蛋白的表达降低，这对于MCLR诱导的肝脏毒性很重要：在啮齿动物中运输多肽1B2（OATP1B2）的有机阴离子在人类中，OATP1B1和OATP1B3。他还表明，这种NASH诱导的啮齿动物OATP1B2的减少将几种是燕麦底物的药物的处置转移到肝脏暴露于肾脏暴露的情况下。在MCLR的情况下，已经表明OATP1B2的遗传敲除完全保护了小鼠免受MCLR诱导的肝毒性的影响。在最近完成的初步研究中，克拉克博士表明，与暴露于MCLR的健康对照相比，NASH中的MCLR暴露显着增加了肾脏毒性。这些数据导致了核心假设，即NASH患者因肝OATP转运蛋白的变化而导致的MCLR暴露和MCLR诱导的肾脏毒性的风险增加。为了检验这一假设并实现该项目的目标，将采用几种方法。首先，将进行体外转运蛋白动力学实验，以识别有助于MCLR处置的燕麦片以外的转运蛋白。其次，NASH对MCLR处置的影响将通过在健康和NASH大鼠的口服和静脉内MCLR给药后测量毒性动物特征来确定。第三，将进行急性和亚基下致命的毒性研究，以确定NASH中的MCLR暴露是否会增加肾脏毒性。最后，将使用SIMCYP软件构建人类MCLR暴露的PBTK模型，以帮助将这项工作转化为人类种群的暴露信息。此处概述的研究项目对于克拉克博士的职业生涯的发展很重要，但更重要的是，对于拥有NASH并暴露于MCLR的全球数百万人来说，这一点很重要。