Intestinal exosomes in alcohol-induces liver injury

酒精中的肠道外泌体诱发肝损伤

• 批准号: 10883964
• 负责人: Je-Hyun Yoon
• 金额: $ 32.63万
• 依托单位: UNIVERSITY OF OKLAHOMA HLTH SCIENCES CTR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10883964
• 关键词: Acetaldehyde; Alcohol-Induced Disorders; Alcoholic Liver Diseases; Alcoholism; Alcohols; Binding; Binding Proteins; Blood; Blood Circulation; CRISPR/Cas technology; CYP2E1 gene; Cells; Chemicals; Circulation; Cytosol; Dissociation; Distant; Endotoxins; Enzymes; Epithelial Cells; Ethanol; Ethanol Metabolism; Extracellular Protein; Family; Fatty Liver; Generations; Genes; Genetic; Genetic Transcription; Hepatic; Hepatocyte; Heterogeneous-Nuclear Ribonucleoprotein K; Human; Individual; Inflammation; Inflammatory; Intestinal permeability; Intestines; Investigation; Knockout Mice; Ligands; Liver; Liver Function Tests; Liver diseases; Measures; Mediating; Messenger RNA; MicroRNAs; Molecular; Mus; Organ; Oxidative Stress Induction; Pathway interactions; Penetration; Phosphorylation; Phosphotransferases; Play; Post-Translational Regulation; Protein-Serine-Threonine Kinases; Proteins; Publishing; RNA; RNA-Binding Proteins; RNA-targeting therapy; Reactive Oxygen Species; Role; Serine; Serum; Signal Pathway; Signal Transduction; Source; Stream; TLR7 gene; Testing; Tissues; Transcriptional Activation; Work; alcohol exposure; alcohol use disorder; cell growth; circulating microRNA; clinically relevant; cohort; cytokine; exosome; feeding; in vivo; inhibitor; insight; intestinal epithelium; liver function; liver inflammation; liver injury; mRNA Decay; mRNA Translation; mouse model; new therapeutic target; novel therapeutics; organ injury; prevent; receptor; response; senescence

PROJECT SUMMARY Although binge alcohol-induced liver injury has been studied extensively in the context of endotoxins and alcohol itself, it was recently revealed that circulating protein and RNA factors play an essential role as well. Ethanol- inducible cytochrome P450-2E1 (CYP2E1), a key enzyme in ethanol metabolism to generate Reactive Oxygen Species (ROS), promotes alcohol-induced hepatic steatosis and inflammatory liver disease, at least in part by mediating changes in intestinal permeability to endotoxins and release of extracellular proteins and RNAs into the blood stream. Specific miRNAs, including let-7 family miRNAs, have been shown to be amplified in serum from alcohol use disorder (AUD) cohorts having decreased liver function, suggesting that these miRNAs contribute to ethanol-induced injury of organs such as the liver. In my published studies and preliminary investigations, I made two key observations that contribute to my scientific premise that let-7b is released from the intestine through exosomes upon binge alcohol: 1) I demonstrated that the RNA-binding protein AUF1 binds mature let-7b miRNA, the ligand of Toll-like Receptor 7 (TLR7) in liver, and that this binding modulates its existence in cytosol and exosome; 2) I showed that the Serine/Threonine kinase MST1 mediates oxidative stress-induced phosphorylation of RNA-binding proteins such as AUF1 and is required for let-7b enrichment in blood exosomes after alcohol binging. This latter finding suggests that ROS-mediated signaling modulates interaction of AUF1 and miRNA through MST1-mediated phosphorylation. Based on these observations, I hypothesize that ethanol-induced activation of MST1 kinase results in the AUF1-dependent exosomal release of let-7b targeting hepatic TLR7, resulting in transcriptional activation of pro-inflammatory cytokines that cause liver injury through hepatic senescence. For this project, we will focus on elucidating the critical functions of AUF1 phosphorylation by MST1 in the dissociation of let-7b from AUF1, the release of let-7b from the intestine to the blood stream via cargo proteins QKI and hnRNP K, and subsequent hepatic injury.

项目摘要 尽管在内毒素和酒精的背景下，已经对暴饮精酒诱导的肝损伤进行了广泛的研究 本身，最近发现循环蛋白和RNA因子也起着至关重要的作用。乙醇 可诱导的细胞色素P450-2E1（CYP2E1），乙醇代谢中的关键酶，可产生活性氧 物种（ROS），促进酒精引起的肝脂肪变性和炎症性肝病，至少部分由 介导肠道通透性对内毒素的变化以及细胞外蛋白和RNA的释放 血液。特定的miRNA，包括Let-7家族miRNA，已显示在血清中被扩增 从肝功能降低的酒精滥用障碍（AUD）同类中，表明这些miRNA 有助于乙醇引起的器官损伤，例如肝脏。在我发表的研究和初步 调查，我做出了两个关键观察，这有助于我的科学前提，即let-7b是从中释放出来的 狂饮时通过外泌体的肠道：1）我证明了RNA结合蛋白AUF1结合 成熟的Let-7b miRNA，肝脏中的Toll样受体7（TLR7）的配体，这种结合调节其 细胞质和外泌体中的存在； 2）我表明丝氨酸/苏氨酸激酶MST1介导氧化 RNA结合蛋白（如AUF1）的应力诱导的磷酸化，是富集在 酒精后血液外泌体。后一个发现表明ROS介导的信号传导调节 AUF1和miRNA通过MST1介导的磷酸化的相互作用。基于这些观察，我 假设乙醇诱导的MST1激酶激活导致AUF1依赖性外泌体释放 Let-7b靶向肝TLR7，导致促炎细胞因子的转录激活，引起肝 通过肝衰老受伤。对于这个项目，我们将专注于阐明AUF1的关键功能 MST1磷酸化在Let-7b与AUF1的解离时，Let-7b从肠释放到肠道 通过货物蛋白QKI和HNRNP K的血液流以及随后的肝损伤。