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: 10415302
• 负责人: Donghun Shin
• 金额: $ 51.49万
• 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/10415302
• 关键词: Bile fluid; Biliary; 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; Pharmacology Study; Phenocopy; Process; Receptor Gene; Research; Role; Signal Transduction; Stat3 protein; Testing; Therapeutic; Zebrafish; base; beta catenin; biliary tract; cholangiocyte; effective therapy; end stage liver disease; gain of function; inhibitor; innovation; insight; liver injury; liver transplantation; mortality; mutant; notch protein; novel; 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 肝胆管树内的胆管上皮细胞（BEC；也称为胆管细胞）控制胆汁 组成和流动。 BEC 损伤会导致胆汁淤积，进而发展为纤维化、肝硬化和肝脏 失败。胆汁淤积性肝病与高发病率和死亡率相关；但有效的却寥寥无几 可以采用治疗方法。事实上，肝移植是终末期胆汁淤积症唯一的延长生命的治疗方法 肝脏疾病，但供体肝脏的短缺使得这种疗法极其有限。在受伤的肝脏中 胆道损伤后，肝细胞 (HC) 可以帮助 BEC 从 BEC 的损失中恢复。最近的研究 小鼠实验表明，HC 衍生的 BEC 有助于肝内胆管，从而恢复适当的胆管功能。 胆汁流量。患有胆道梗阻或胆管病的患者在 HC 中也表现出胆道标志物表达， 建议将它们重新编程为 BEC。因此，在胆汁淤积症中增强先天 HC 至 BEC 重编程 肝脏疾病是改善胆汁淤积和随后的肝硬化的一种有吸引力的替代治疗方法。到 开发这样的疗法，更好地了解 HC 转化为 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该提供 胆汁淤积性肝病患者的有前景的治疗药物。我们的长期目标是彻底 描述 HC 至 BEC 重编程的分子机制。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 我们的两个创新斑马鱼模型中重编程驱动的胆道再生，并阐明组蛋白如何 脱乙酰酶 1 (hdac1) 调节 HC 至 BEC 重编程。根据我们获得的初步数据 药理学和遗传学研究中，我们假设 Hdac1 抑制促进 HC 到 BEC 重编程 通过去抑制Notch受体基因notch2和转录3基因的信号转导子和激活子 （统计3）。我们将测试这个假设并通过（1）阐明整个应用程序的目标来实现 在两个斑马鱼模型中HC到BEC重编程驱动的胆道再生过程，其中完成 实现了 BEC 的缺失，随后 HC 转化为 BEC。 （目标 1）、（2）确定效果 Hdac1 对斑马鱼和小鼠中 HC 至 BEC 重编程的抑制（目标 2），以及 (3) 阐明 Hdac1 抑制促进重编程的分子机制（目标 3）。成功者 拟议研究的完成不仅将提供 HC-to- 的新分子机制 BEC 重编程还表明 HDAC1/2 抑制剂作为有前途的治疗药物来促进 胆汁淤积性肝病患者的重编程。