ALCOHOL-INDUCED LIVER FIBROSIS--AN IN VITRO MODEL

酒精引起的肝纤维化——体外模型

• 批准号: 2045465
• 负责人: MARCOS ROJKIND
• 金额: $ 23.7万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-04-01 至 1997-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2045465
• 关键词: DNA footprinting; Kupffer's cell; SDS polyacrylamide gel electrophoresis; acetaldehyde; adipocytes; affinity chromatography; alcoholic fatty liver; alcoholic liver cirrhosis; alcoholism /alcohol abuse; binding proteins; clone cells; collagen; complementary DNA; cytokine; deoxyribonuclease I; diagnosis design /evaluation; disease /disorder model; ethanol; fibronectins; fibrosis; gel mobility shift assay; genetic promoter element; genetic regulatory element; genetic transcription; liver cells; liver metabolism; macroglobulins; messenger RNA; molecular genetics; monoclonal antibody; neutralizing antibody; nucleic acid sequence; oligonucleotides; pulsed field gel electrophoresis; radiotracer; tissue /cell culture; transcription factor; transforming growth factors

Ethanol-induced liver cirrhosis is a major cause of death worldwide. The exact mechanism by which ethanol (ETOH) induces liver fibrosis is unknown but several hypothesis have been proposed: a) Products derived from either ETOH metabolism or injured cells activate Kupffer cells to produce cytokines that induce fat-storing cell (FSC) proliferation and excess collagen production. b) Inflammatory cells driven to the liver by chemoattactants produce cytokines that induce fibrogenesis. c) Products derived from ETOH metabolism or injured cells are fibrogenic and directly induce collagen gene expression. The various mechanisms may occur simultaneously,l however, their relative contribution to fibrogenesis is unknown. Lack of appropriate models to study alcohol-induced liver cirrhosis has hampered understanding of basic mechanisms by which ETOH induces liver fibrosis. Baboon and rat models are costly and unavailable for routine studies. We developed a co-culture, system that contains two of the important cells involved in alcoholic fibrosis, hepatocytes and FSCs. While the former transform ETOH to acetaldehyde (ACAL), the latter respond to ACAL by increasing transcription of type I collagen gene. Therefore, this model of liver fibrosis could be useful in exploring the mechanisms by which ETOH and other hepatotoxins induce hepatocyte damage and liver fibrosis. The model is simple, reproducible and can be analyzed in the absence or presence of inflammatory components. Our specific aims are to determine: a) the relative contribution of hepatocytes and FSC to collagen production after ETOH or ACAL administration and, b) to determine at the molecular level, possible mechanisms by which ETOH and/or ACAL induce the expression of type I collagen mRNA. We shall determine whether the effects are mediated 'via' the production of TGF-beta or other cytokines. We shall establish whether specific sequences in the promoter of type I collagen are required for collagen gene expression after ETOH or ACAL administration, and we shall attempt to study whether specific nuclear proteins are required for transcriptional activation of type I collagen gene. Our long-term goals are to understand the mechanisms of induction of liver fibrosis, and to develop drugs with antifibrogenic activity capable of preventing or reverting fibrosis.

乙醇引起的肝硬化是全球死亡的主要原因。 这 乙醇（ETOH）诱导肝纤维化的确切机制未知 但是已经提出了几种假设：a）来自任何一个的产品 EtOH代谢或受伤的细胞激活库普弗细胞以产生 诱导脂肪细胞（FSC）增殖和过量的细胞因子 胶原蛋白生产。 b）炎症细胞通过 化学毒剂产生诱导纤维化的细胞因子。 c）产品 源自EtOH代谢或受伤细胞的纤维纤维，直接 诱导胶原基因表达。 可能发生各种机制 同时，l然而，它们对纤维化的相对贡献是 未知。 缺乏研究酒精诱发的肝硬化的合适模型已有 对ETOH诱导肝脏的基本机制的理解阻碍了理解 纤维化。 狒狒和老鼠的模型对于常规而言是昂贵且不可用的 研究。 我们开发了一个共同文化，其中包含两个 参与酒精纤维化，肝细胞和FSC的重要细胞。 前者转化为乙醛（ACAL），后者响应 通过增加I型胶原蛋白基因的转录来达到ACAL。 所以， 这种肝纤维化模型可用于探索通过 ETOH和其他肝毒素会诱导肝细胞损伤和肝脏 纤维化。 该模型很简单，可重现，可以在 炎症成分的不存在或存在。 我们的具体目的是 确定：a）肝细胞和FSC对胶原蛋白的相对贡献 ETOH或ACAL给药后的生产，b）确定 分子水平，ETOH和/或ACAL诱导的可能机制 I型胶原mRNA的表达。 我们将确定效果是否 被介导的“通过” TGF-β或其他细胞因子的产生。 我们将 确定I型胶原蛋白启动子中的特定序列是否为 ETOH或ACAL给药后胶原蛋白基因表达所必需的， 我们将尝试研究特定的核蛋白是否是 I型胶原基因的转录激活所必需的。 我们的 长期目标是了解肝脏诱导的机制 纤维化，并开发具有抗纤维化活性的药物 防止或恢复纤维化。