The MicroRNA Network and the Deregulation of Liver Regeneration by Ethanol

MicroRNA 网络和乙醇对肝脏再生的失调

• 批准号: 8730532
• 负责人: Joannes B Hoek
• 金额: $ 17.85万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-05 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8730532
• 关键词: Accounting; Acute; Alcohol consumption; Alcoholic Liver Diseases; Alcoholic liver damage; Alcohols; Animal Feed; Animals; Cell Communication; Cell Cycle Progression; Cell Proliferation; Cells; Chronic; Control Animal; Data; Endothelial Cells; Ethanol; Ethanol dependence; Excision; Future; Gene Expression; Gene Expression Profiling; Gene Expression Regulation; Gene Targeting; Genes; Goals; Hepatic Mass; Hepatic Stellate Cell; Hepatocyte; Immunoprecipitation; Individual; Inhibition of Cell Proliferation; Kupffer Cells; Liver; Liver Regeneration; Mechanics; Mediating; Mediator of activation protein; Messenger RNA; MicroRNAs; Modeling; Molecular Profiling; Natural regeneration; Nature; Operative Surgical Procedures; Partial Hepatectomy; Pattern; Play; Population; Primary carcinoma of the liver cells; Process; Protocols documentation; Publishing; Rattus; Recovery; Relative (related person); Reporting; Resolution; Role; S Phase; Signal Transduction; Staging; Technology; Testing; Time; Tissues; Transcription Regulatory Protein; Up-Regulation; Viral; alcohol effect; alcohol exposure; base; cell type; crosslink; digital; feeding; in vivo; interest; laser capture microdissection; liver cell proliferation; liver repair; locked nucleic acid; mouse model; nano-string; novel; programs; public health relevance; regenerative; repaired; research study; response; restoration; stellate cell; tissue repair; transcriptome sequencing

DESCRIPTION (provided by applicant): Liver regeneration is a clinically important tissue repair mechanism that facilitates the recovery of liver mass after acute damage through proliferation of fully differentiated hepatocytes. Chronic ethanol intake interferes with the process of liver regeneration, which may contribute to the progression of alcoholic liver disease. We and others have found that chronic ethanol feeding alters the pattern of microRNA changes occurring in the remnant liver after partial hepatectomy (PHx) in the rat. Remarkably, our studies demonstrated that a presumed pro-proliferative microRNA species, miR-21, was increased in the remnant liver in ethanol-fed rats under conditions where hepatocyte proliferation was severely inhibited. Moreover, inhibition of miR-21 by the administration of a locked nucleic acid (LNA) antagonist of miR-21 (AM21) could overcome the ethanol- induced suppression of liver cell proliferation after PHx, suggesting that miR-21 contributes to ethanol- dependent inhibition of regeneration. A gene expression profiling analysis of the remnant liver demonstrated that a cluster of pro-fibrogenic hepatic stellate cell (HSC) markers was upregulated in ethanol-fed rats after PHX, but the upregulation of this cluster was suppressed in AM21-treated animals, indicating that HSC activation may play a role in the ethanol suppression of liver regeneration. Interestingly, inhibition of miR-21 by AM21 caused a concomitant upregulation of a cluster of other microRNAs, suggesting the involvement of a network of regulatory microRNAs mediating the recovery of regeneration in ethanol-treated animals. We propose to analyze the cell-type specific processes in the regenerating liver that are targeted by this regulatory microRNA network. The following specific aims are proposed: 1) To evaluate the role of miR-21 and its interacting miRNA regulatory network as cell type specific mediators of the suppressive effect of ethanol on the regenerative response to PHx. This will involve identifying miR-21 targets by HITS-CLIP analysis and analyzing populations of parenchymal cells, stellate cells and other cell types obtained from the remnant tissue by laser capture microdissection (LCM) for microRNA changes and corresponding changes in gene expression; 2) To evaluate the network roles of microRNA species that show parallel or anti-parallel changes relative to miR-21 in the response to PHx in AM21-treated animals and assessing their role in the recovery from ethanol inhibition of cell proliferation. These exploratory studies will guide a future in-depth analyses of the natur of the alcohol-induced deregulation of the microRNA network in liver regeneration with the long-term potential of identifying novel targets for therapy of alcoholic liver disease.

描述（由申请方提供）：肝再生是一种临床上重要的组织修复机制，通过完全分化的肝细胞增殖促进急性损伤后肝脏质量的恢复。慢性酒精摄入会干扰肝脏再生过程，这可能会导致酒精性肝病的进展。我们和其他人发现，慢性乙醇喂养改变了大鼠部分肝切除术（PHx）后残肝中microRNA变化的模式。值得注意的是，我们的研究表明，在肝细胞增殖受到严重抑制的条件下，一种假定的促增殖microRNA种类miR-21在乙醇喂养的大鼠的残肝中增加。此外，通过施用miR-21的锁核酸（LNA）拮抗剂（AM 21）抑制miR-21可以克服PHx后乙醇诱导的肝细胞增殖抑制，表明miR-21有助于乙醇依赖性的再生抑制。残肝的基因表达谱分析表明，一组促纤维化肝星状细胞（HSC）标志物在PHX后乙醇喂养的大鼠中上调，但这一组的上调在AM 21治疗的动物中受到抑制，表明HSC活化可能在乙醇抑制肝再生中发挥作用。有趣的是，AM 21对miR-21的抑制引起了一组其他microRNA的伴随上调，这表明参与调节microRNA网络介导了乙醇处理动物的再生恢复。我们建议分析再生肝脏中的细胞类型特异性过程，这些过程是由这种调控microRNA网络靶向的。本研究的具体目的如下：1）评估miR-21及其相互作用的miRNA调控网络作为乙醇抑制PHx再生反应的细胞类型特异性介质的作用。这将涉及通过HITS-CLIP分析鉴定miR-21靶标，并通过激光捕获显微切割（LCM）分析从残余组织获得的实质细胞、星状细胞和其他细胞类型的群体的microRNA变化和基因表达的相应变化; 2）为了评估在AM 21中对PHx的响应中显示相对于miR-21平行或反平行变化的microRNA种类的网络作用，处理的动物并评估它们在从乙醇抑制细胞增殖中恢复中的作用。这些探索性研究将指导未来深入分析酒精诱导的肝脏再生中microRNA网络失调的性质，并具有确定酒精性肝病治疗新靶点的长期潜力。