Role of FGF10 in liver organogenesis and alcohol-impaired regeneration

FGF10 在肝器官发生和酒精损伤再生中的作用

• 批准号: 7918768
• 负责人: KASPER SAONUN WANG
• 金额: $ 17.39万
• 依托单位: CHILDREN'S HOSPITAL OF LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-25 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7918768
• 关键词: Adult; Alcohol abuse; Alcoholic Liver Diseases; Alcohols; Artificial Liver; Cell Proliferation; Cell Separation; Cells; Cirrhosis; Data; Dependence; Development; Dominant-Negative Mutation; Embryo; Embryonic Development; Endoderm; Epithelium; Ethanol; Exhibits; Fibroblast Growth Factor Receptor 2; Fluorescence; Fluorescence-Activated Cell Sorting; Galactosidase; Gastrointestinal tract structure; Genes; Growth Factor; Health; Healthcare; Hepatectomy; Hepatic; Hepatic Fibrogenesis; Hepatic Stellate Cell; Hepatocyte; Hydrolysis; Immunofluorescence Immunologic; Impairment; In Vitro; Ingestion; LacZ Genes; Lead; Ligands; Liver; Liver Cirrhosis; Liver Regeneration; Liver diseases; Mediating; Mesenchymal; Mesenchyme; Mesoderm; Methods; Modeling; Molecular; Morbidity - disease rate; Mus; Mutant Strains Mice; Myofibroblast; Natural regeneration; Nuclear Translocation; Organogenesis; Partial Hepatectomy; Pathway interactions; Pattern; Play; Population; Prevention; Primitive foregut structure; Process; Protein Isoforms; Relative (related person); Reporter; Research Personnel; Role; Signal Transduction; Societies; Sorting - Cell Movement; Staging; Stem cells; Time; Transgenic Mice; Transgenic Organisms; United States; Up-Regulation; WNT Signaling Pathway; autocrine; base; cell type; cost; early embryonic stage; feeding; fetal; fibroblast growth factor 10; gain of function; in vivo; insight; intestinal crypt; liver transplantation; loss of function; mortality; mutant; novel; organ regeneration; oval cell; overexpression; postnatal; programs; receptor; repaired; response to injury; stellate cell

DESCRIPTION (provided by applicant): This proposal focuses on the potential role of reduced FGF10 signaling in the setting of ethanol (EtOH) impaired liver regeneration. FgflO, expressed in the embryonic foregut mesoderm, normally interacts with the adjacent endoderm through Fibroblast Growth Factor Receptor 2 1Mb (FGFR2b). Absence of signaling through FGFR2b results in atresias of numerous gastrointestinal tract structures. We have preliminary evidence showing that FGF10 activates canonical WNT signaling in the developing liver through FGFR2b. Our studies indicate that Fgf 10 is expressed by activated hepatic stellate cells, which play a key role in liver fibrogenesis, and that Fgfr2b is expressed by progenitor cells, hepatoblasts prenatally and oval cells postnatally. Consistent with the observation that FGFR2b signaling is activated during liver regeneration, we have evidence that Fgf 10 expression, which is upregulated after partial hepatectomy, is reduced in the setting of ethanol-induced impaired liver regeneration. We hypothesize that ethanol suppresses signaling through the FGF10/FGFR2b, thus, impairing progenitor cell proliferation. We thus propose the following specific aims: (1) To determine the role of FGF10 signaling via FGFR2b during liver regeneration following partial hepatectomy (PH) in the absence or presence of EtOH in transgenic mice. Liver-specific induced overexpression of the dominant negative soluble FGFR2b isoform or of Fgf 10 in the setting of EtOH impaired liver regeneration following PH will be performed for loss-of-function or gain-of-function analyses, respectively. (2) To determine the identity and role of Fgf 10-expressing cells in hepatogenesis and EtOHimpaired liver regeneration. Cells expressing Fgf 10 from transgenic embryo livers and PH livers exposed to EtOH will be sorted by fluorescence activated cell sorting (FACS) and characterized by real-time PCR. (3) To determine the identity of cells undergoing FGF10-mediated canonical WNT activation. Cells with activated canonical WNT signaling will be sorted by FACS. Loss and gain-of function analyses for FgflO will be performed to determine relative levels of canonical WNT activiation. Alcohol impairs the liver's ability to repair and regenerate itself. This contributes to the development of liver cirrhosis. We postulate that the mechanism by which alcohol impairs liver regeneration may be due to impaired signaling through the FGF10/FGFR2b pathway we show normally promotes liver regeneration.

描述（由申请人提供）：该提案重点关注FGF 10信号传导减少在乙醇（EtOH）损伤肝再生中的潜在作用。在胚胎前肠中胚层中表达的FgflO通常通过成纤维细胞生长因子受体21 Mb（FGFR 2b）与相邻的内胚层相互作用。缺乏通过FGFR 2b的信号传导导致许多胃肠道结构的闭锁。我们有初步证据表明，FGF 10通过FGFR 2b激活发育中肝脏中的经典WNT信号传导。我们的研究表明，Fgf 10由活化的肝星状细胞表达，在肝纤维化中起关键作用，Fgfr 2b由前体细胞、成肝细胞和生后卵圆细胞表达。与FGFR 2b信号传导在肝再生过程中被激活的观察结果一致，我们有证据表明在部分肝切除术后上调的Fgf 10表达在乙醇诱导的肝再生受损的情况下减少。我们假设乙醇通过FGF 10/FGFR 2b抑制信号传导，从而损害祖细胞增殖。因此，我们提出以下建议： 具体目标：（1）确定在转基因小鼠中，在不存在或存在EtOH的情况下，在部分肝切除术（PH）后的肝再生期间，FGF 10经由FGFR 2b的信号传导的作用。在PH后EtOH损伤肝再生的情况下，将分别进行显性阴性可溶性FGFR 2b同种型或Fgf 10的肝脏特异性诱导过表达，以进行功能丧失或功能获得分析。(2)确定Fgf 10表达细胞的特性及其在肝发生和乙醇损伤的肝再生中的作用.来自暴露于EtOH的转基因胚胎肝脏和PH肝脏的表达Fgf 10的细胞将通过荧光激活细胞分选（FACS）进行分选，并通过实时PCR进行表征。(3)确定经历FGF 10介导的典型WNT活化的细胞的身份。具有活化的经典WNT信号传导的细胞将通过FACS分选。将进行FgflO的功能丧失和获得分析，以确定典型WNT活化蛋白的相对水平。酒精会损害肝脏的自我修复和再生能力。这有助于肝硬化的发展。我们推测，酒精损害肝再生的机制可能是由于通过FGF 10/FGFR 2b通路的信号传导受损，我们显示正常情况下促进肝再生。

项目成果

Fibroblast growth factor signaling regulates the expansion of A6-expressing hepatocytes in association with AKT-dependent β-catenin activation.

• DOI: 10.1016/j.jhep.2013.12.017
• 发表时间: 2014-05
• 期刊: JOURNAL OF HEPATOLOGY
• 影响因子: 25.7
• 作者: Utley, Sarah;James, David;Mavila, Nirmala;Nguyen, Marie V.;Vendryes, Christopher;Salisbury, S. Michael;Phan, Jennifer;Wang, Kasper S.
• 通讯作者: Wang, Kasper S.