Delineating the molecular mechanisms of hepatocyte-to-cholangiocyte reprogramming

描述肝细胞到胆​​管细胞重编程的分子机制

• 批准号: 10596146
• 负责人: Donghun Shin
• 金额: $ 51.69万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10596146
• 关键词: Bile fluid; Biliary; Cell Reprogramming; Cell model; Characteristics; Chemicals; Cholestasis; Cirrhosis; Data; EP300 gene; Epithelial Cells; Exhibits; Fibrosis; Gene Expression Regulation; Genes; Genetic; Genetic study; Goals; HDAC1 gene; Hepatic; Hepatocyte; Histone Acetylation; Image; Injury; Intrahepatic bile duct; Life; Liver; Liver Failure; Liver Regeneration; Liver diseases; MS-275; Mediating; Modeling; Molecular; Morbidity - disease rate; Mus; Natural regeneration; Obstruction; Pathway interactions; Patients; Pharmaceutical Preparations; Pharmacology Study; Phenocopy; Process; Receptor Gene; Research; Role; Signal Transduction; Stat3 protein; Testing; Therapeutic; Zebrafish; beta catenin; biliary tract; cholangiocyte; derepression; effective therapy; end stage liver disease; gain of function; inhibitor; innovation; insight; liver injury; liver transplantation; loss of function; mortality; mutant; notch protein; novel; pharmacologic; small molecule; tool; transdifferentiation

ABSTRACT Biliary epithelial cells (BECs; also called as cholangiocytes) that line the hepatic biliary tree control bile composition and flow. Injury to the BECs leads to cholestasis, which can progress to fibrosis, cirrhosis and liver failure. Cholestatic liver diseases are associated with high morbidity and mortality; however, few effective therapies are available. In fact, liver transplantation is the only life-extending treatment for end-stage cholestatic liver diseases, but the shortage of donor livers makes this therapy extremely limited. In the injured liver with biliary damage, hepatocytes (HCs) can contribute to BECs to recover from the loss of BECs. Recent studies in mice have shown that HC-derived BECs contribute to the intrahepatic bile ducts, thereby restoring appropriate bile flow. Patients with biliary obstruction or cholangiopathies also exhibit biliary marker expression in HCs, suggesting their reprogramming into BECs. Thus, augmenting innate HC-to-BEC reprogramming in cholestatic liver diseases is an attractive therapeutic alternative to ameliorate cholestasis and subsequent cirrhosis. To develop such a therapy, it is crucial to better understand the molecular mechanisms underlying HC-to-BEC reprogramming. Furthermore, identifying small molecules that can augment the reprogramming should provide promising therapeutic drugs for patients with cholestatic liver diseases. Our long-term goal is to completely delineate the molecular mechanisms underlying HC-to-BEC reprogramming. As a first step in pursuit of that goal, the objective of this proposal is to determine the cellular and molecular characteristics of HC-to-BEC reprogramming-driven biliary regeneration in our two innovative zebrafish models and to elucidate how histone deacetylase 1 (hdac1) regulates HC-to-BEC reprogramming. Based on our preliminary data obtained from pharmacological and genetic studies, we hypothesize that Hdac1 inhibition promotes HC-to-BEC reprogramming by derepressing the Notch receptor gene notch2 and the signal transducer and activator of transcription 3 gene (stat3). We will test this hypothesis and accomplish the objective of this application by (1) elucidating the entire process of HC-to-BEC reprogramming-driven biliary regeneration in the two zebrafish models, in which complete absence of BECs is achieved and subsequently HCs convert to BECs. (Aim 1), (2) determining the effects of Hdac1 inhibition on HC-to-BEC reprogramming in both zebrafish and mice (Aim 2), and (3) elucidating the molecular mechanisms by which Hdac1 inhibition promotes the reprogramming (Aim 3). The successful accomplishment of the proposed research will not only provide novel molecular mechanisms underlying HC-to- BEC reprogramming but also suggest HDAC1/2 inhibitors as promising therapeutic drugs to promote the reprogramming in patients with cholestatic liver diseases.

抽象的 胆道上皮细胞（BEC；也称为胆管细胞），将肝胆道控制胆汁排列 组成和流动。 BEC的损伤导致胆汁淤积，可以发展为纤维化，肝硬化和肝脏 失败。胆固性肝病与高发病率和死亡率有关。但是，很少有效 提供疗法。实际上，肝移植是终末期胆汁淤积的唯一延长生命的治疗方法 肝病，但供体肝脏的短缺使得这种疗法极为有限。在受伤的肝脏中 胆道损害，肝细胞（HCS）可以为BEC恢复BEC的损失。最近的研究 小鼠表明，HC衍生的BEC有助于肝内胆管，从而恢复适当 胆汁流。胆道阻塞或胆管病的患者在HCS中也表现出胆道标记的表达， 建议他们重新编程为BEC。因此，增强胆汁淤积的先天性HC到BEC重新编程 肝脏疾病是改善胆汁淤积和随后的肝硬化的有吸引力的治疗替代品。到 发展这种疗法，更好地了解HC至BEC的分子机制至关重要 重新编程。此外，识别可以增强重编程的小分子应提供 胆固性肝疾病患者的有希望的治疗药物。我们的长期目标是完全 描述HC至BEC重新编程的基于的分子机制。作为追求这一目标的第一步， 该提案的目的是确定HC至BEC的细胞和分子特征 在我们的两个创新的斑马鱼模型中，重编程驱动的胆道再生，并阐明了组蛋白的方式 脱乙酰基酶1（HDAC1）调节HC至BEC重编程。基于我们从中获得的初步数据 药理学和遗传研究，我们假设HDAC1抑制促进了HC至BEC重新编程 通过解压缩Notch受体基因Notch2和转录3基因的信号转换器和激活因子 （Stat3）。我们将通过（1）阐明整个假设来检验该假设，并实现此应用的目标 在两个模型中，HC至BEC重编程驱动的胆道再生的过程，其中完整 实现了BEC的缺乏，随后HCS转换为BEC。 （目标1），（2）确定 HDAC1抑制斑马鱼和小鼠的HC至BEC重编程（AIM 2），以及（3）阐明 HDAC1抑制促进重编程的分子机制（AIM 3）。成功 提出的研究的完成不仅将提供HC-to-to-to-to-to-to-to-the Solecular机制 重新编程，但也建议HDAC1/2抑制剂作为有希望的治疗药物来促进 胆汁淤积性肝病患者的重编程。