m6A Epitranscriptomics in Toxicant Associated Steatohepatitis

m6A 表观转录组学在中毒性相关脂肪性肝炎中的应用

基本信息

批准号：
10220036
负责人：
Matthew C Cave
金额：
$ 28.86万
依托单位：
UNIVERSITY OF LOUISVILLE
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-20 至 2023-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10220036
关键词：
Address Adenosine Adipose tissue Affect Alternative Splicing Animal Model Antibodies Aryl Hydrocarbon Receptor Attenuated Biological Markers C57BL/6 Mouse Cessation of life Cirrhosis Data Diet Dioxygenases Disease Dose Environmental Exposure Environmental Pollutants Environmental Pollution Enzymes Epidermal Growth Factor Euthanasia Event Exposure to Fatty Liver Fatty acid glycerol esters Female Fibrosis Functional disorder Future Genes Goals Health Hepatic Hepatocyte High Fat Diet Histology Homeostasis Human Hypertriglyceridemia Immunoprecipitation Inflammation Knockout Mice Liver Liver Extract Liver diseases Measures Mediating Messenger RNA Metabolic Diseases Methyltransferase MicroRNAs Modeling Modification Mus Necrosis Nuclear Receptors Nutrient Nutritional Outcome Pathology Pathway Analysis Play Polychlorinated Biphenyls Positioning Attribute Primary carcinoma of the liver cells Protein Methyltransferases Proteins Proteome RNA RNA Splicing Reader Receptor Inhibition Regulation Reporting Role Sampling Sex Differences Signal Pathway Signal Transduction Steatohepatitis Stress Testing Therapeutic Intervention Time Transcript Translations Untranslated RNA Western Blotting base bioaccumulation circulating microRNA cohort constitutive androstane receptor epitranscriptome epitranscriptomics human subject in vivo knock-down lipid metabolism liver function liver transplantation mRNA sequencing male methyl group mortality non-alcoholic fatty liver disease overexpression pregnane X receptor protein complex protein expression receptor response sex sexual dimorphism targeted treatment toxicant transcriptome transcriptome sequencing virtual western diet

项目摘要

Project Summary/Abstract Exposure to persistent environmental contaminants including polychlorinated biphenyls (PCBs) contributes to metabolic diseases including toxicant-associated steatohepatitis (TASH), a form of nonalcoholic fatty liver disease (NAFLD). PCBs have been positively associated with TASH, hepatocellular cancer, altered liver enzymes, and mortality in human cohorts. A complete understanding of the mechanisms by which PCBs act as a 1st ‘hit’ in combination with a high fat ‘Western diet’ (HFD) as a 2nd ‘hit’ to increase triglyceride accumulation, fibrosis, and inflammation in the liver (hallmarks of TASH) remains elusive. Further, although liver sexual dimorphism is well-established and sex-specific differences in human health outcomes after PCB exposure have been reported, there are few mechanistic studies addressing these differences. N(6)-methyladenosine (m6A) is the most common dynamic modification of transcribed RNAs. The regulation and role of m6A in liver epitranscriptomics and the impact of PCB exposure is unknown. This application addresses RFA-ES-19-002 by investigating the role of altered m6A and its writers, readers, and erasers in TASH in vivo, using an established PCB exposure model. Preliminary RNA-seq data show that liver from HFD + Aroclor 1260 (PCB) exposed male C57BL/6J mice have reduced transcript levels of the m6A methyltransferase complex protein Rbm15 and altered levels of the m6A readers Ythdf1 and Ythdc1/2. Whether these HFD + Aroclor 1260-induced changes are also occur in females and how they affect the m6A epitranscriptome and hepatocyte homeostasis or liver function is unknown. We recently reported increased PCB-induced hepatic inflammation and altered lipid metabolism in female vs. male mice. The goal of this exploratory study is to determine the impact of PCB +/- HFD exposure in vivo on the hepatic m6A epitranscriptome in male and female mice. We will test the hypothesis that altered m6A levels of specific transcripts play a role in TASH in vivo. Integrated analysis will identify m6A epitranscriptome- mediated changes in signaling pathways regulating TASH pathophysiology. This goal will be achieved by 1) Identification of m6A-mediated transcriptome changes in HFD, Aroclor 1260 (a mixture of non-dioxin-like (NDL) PCB subtypes that best mimics the PCB bioaccumulation in human adipose tissue), and HFD + Aroclor 1260 – exposed male and female mouse liver; 2) Determination if HFD, Aroclor 1260, or HFD + Aroclor 1260 exposure alter the expression of the writers, readers, and erasers of m6A in mouse liver. Integrated analysis will identify m6A epitranscriptome-mediated changes in signaling pathways regulating TASH pathophysiology that may be targets for therapeutic intervention. In the future, knockdown or overexpression of key proteins identified in this study will confirm their role in the observed m6A changes and in downstream signaling.

项目摘要/摘要暴露于包括多氯联苯（PCB）在内的持续环境污染物，有助于代谢性疾病，包括毒物相关的脂肪性肝炎（TASH），一种非酒精性脂肪肝的形式疾病（NAFLD）。 PCB与TASH，肝细胞癌和改变肝脏的呈正相关酶和人类人群中的死亡率。完全理解PCB的机制第一个“命中”与高脂肪的“西部饮食”（HFD）结合在一起，作为第二个“命中”，以增加甘油三酸酯的积累，纤维化和肝脏的炎症（塔什的标志）仍然难以捉摸。此外，尽管肝脏性二态性是良好的，PCB暴露后人类健康结果的特定性别差异据报道，很少有关于这些差异的机械研究。 n（6） - 甲基腺苷（M6A）为转录RNA的最常见动态修饰。 M6a在肝脏中的调节和作用表面转录组学和PCB暴露的影响尚不清楚。该申请通过使用既定 PCB暴露模型。初步RNA-seq数据显示，HFD + Aroclor 1260（PCB）暴露于男性的肝脏 C57BL/6J小鼠的M6A甲基转移酶复合蛋白RBM15的转录水平降低并改变了 M6A读取器YTHDF1和YTHDC1/2的水平。这些HFD + Aroclor 1260引起的变化是否也是发生在女性中以及它们如何影响M6a的表面见面组和肝细胞稳态或肝功能是未知。我们最近报道了PCB诱导的肝脏注射量增加并改变了脂质代谢雌性与雄性老鼠。这项探索性研究的目的是确定PCB +/- HFD暴露在男性和雌性小鼠的肝M6a同胞体的体内体内。我们将检验改变M6A的假设特定转录物的水平在体内Tash中起作用。综合分析将确定M6A的表演组 - 调节TASH病理生理学的信号通路的介导变化。这个目标将通过1实现） HFD中M6A介导的转录组变化的鉴定，Aroclor 1260（非二恶英（NDL）的混合物 PCB亚型最能模仿人脂肪组织中的PCB生物蓄积）和HFD + Aroclor 1260 - 暴露于雄性小鼠肝； 2）确定HFD，Aroclor 1260或HFD + Aroclor 1260暴露改变小鼠肝脏中M6A的作者，读者和橡皮擦的表达。综合分析将确定 M6a的表演表介导的信号通路的变化调节可能是TASH病理生理学的变化热干预的目标。将来，在此确定的关键蛋白的敲低或过表达研究将确认它们在观察到的M6A变化和下游信号传导中的作用。