Cholesterol toxicity in alcohol-associated hepatitis

酒精相关性肝炎中的胆固醇毒性

• 批准号: 10637154
• 负责人: Zhenghui Gordon Jiang
• 金额: $ 70.15万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-15 至 2028-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10637154
• 关键词: Acute; Acyltransferase; Alcoholic Hepatitis; Alcoholic Liver Diseases; Alcohols; Atlases; Bile Acid Biosynthesis Pathway; Bile Acids; Binding; Blood; Cells; Cholestasis; Cholesterol; Cholesterol 7-alpha-Monooxygenase; Cholesterol Homeostasis; Chronic; Development; Disease; Disease model; Enzymes; Esterification; Exhibits; Experimental Models; Functional disorder; HNF4A gene; Hepatitis; Hepatocyte; Hepatotoxicity; Human; Impairment; In Vitro; Individual; Knowledge; Lecithin; Link; Lipoproteins; Liver; Liver Failure; Liver diseases; Maps; Messenger RNA; Metabolic Pathway; Modeling; Mus; Nuclear RNA; Pathogenesis; Pathogenicity; Pathway interactions; Patients; Production; Protein Isoforms; Proteins; RNA; RNA Interference; Regulatory Pathway; Resolution; Route; Sampling; Scientist; Technology; Testing; Therapeutic; Toxic effect; Transgenic Model; Transportation; Treatment Efficacy; Up-Regulation; Very low density lipoprotein; efficacy testing; feeding; first-in-human; hepatocyte nuclear factor; in vivo; mortality; mouse model; multidisciplinary; multimodality; multiplexed imaging; novel; novel therapeutic intervention; pre-clinical; predict clinical outcome; reverse cholesterol transport; screening; success; targeted treatment; therapeutic target; tool; transcription factor; transcriptome sequencing; transcriptomics; treatment strategy; uptake

SUMMARY Alcohol-associated hepatitis (AH) is a form of subacute liver failure with high mortality, limited treatment options, and elusive pathogenesis. Emerging evidence suggests that AH is associated with a profound impairment in hepatocellular cholesterol homeostasis. Hepatocytes are the central hub for cholesterol metabolism. Meanwhile, AH hepatocytes exhibit profoundly altered FC content and pathways responsible for cholesterol esterification, transport, and conversion to bile acids. RNA sequencing studies indicate that the dysregulation of HNF4α, a master hepatocyte transcription factor, is responsible for impaired cholesterol homeostasis. Upregulation of HNF4α using small activating RNA (saRNA) could mitigate cholesterol toxicity in vitro and can be developed as a treatment for AH. Our long-term objective is to define the disease-centric pathways of AH and develop much-needed therapeutics for AH patients. We hypothesize that the HNF4a-dependent impairment of cholesterol homeostasis in hepatocytes directly contributes to hepatocellular dysfunction in AH and can be targeted therapeutically. Our approach is to map regulatory pathways of cholesterol metabolism in human AH at a single cell resolution, functionally interrogate cholesterol metabolic pathways in murine alcohol models, and test a novel therapeutic strategy by targeting HNF4a-dependent cholesterol toxicity. Aim 1 will map cholesterol metabolism in AH at single cell resolution using a multimodal approach. A three- pronged strategy will map AH-associated changes in cholesterol homeostasis using single nuclear RNA sequencing, ultra-high multiplexed imaging, and targeted spatial transcriptomics. The unbiased reference maps will guide the interrogation of cholesterol metabolic pathways in cell and murine AH models. Aim 2 will define the impact of cholesterol dysregulation on alcohol-induced liver injury in murine models. We will model cholesterol toxicity in 3 conditions relevant to AH using the chronic-plus-binge alcohol feeding: (1) acute cholesterol overload, (2) impaired bile acid synthesis, and (3) impaired cholesterol secretion in cholestasis. This effort will generate optimized murine models that recapitulate cholesterol toxicity in AH. Aim 3 will evaluate targeted manipulation of HNF4α-dependent pathways of cholesterol toxicity as a novel therapeutic strategy in AH. We use saRNA to modulate HNF4α isoform expression and cholesterol metabolism. GalNAc-conjugated HNF4α-saRNA will be tested as a hepatocyte-targeted therapeutics to mitigate cholesterol toxicity in models of AH using differentiated human hepatocytes and murine models. This project is built upon a strong team of multidisciplinary scientists combining unique expertise in lipidology, preclinical liver models, and state-of-the-art single cell and spatial technologies. The success of this project will further our understanding of AH pathogenesis and could lead to the development of a novel AH treatment ready for preclinical and first-in-human trials.

概括 酒精相关性肝炎 (AH) 是一种亚急性肝衰竭，死亡率高，治疗有限 选择和难以捉摸的发病机制。新出现的证据表明，AH 与深刻的 肝细胞胆固醇稳态受损。肝细胞是胆固醇的中枢 代谢。同时，AH 肝细胞表现出深刻改变的 FC 含量和通路，负责 胆固醇酯化、运输和转化为胆汁酸。 RNA 测序研究表明 HNF4α（一种主要肝细胞转录因子）的失调是导致胆固醇受损的原因 体内平衡。使用小激活 RNA (saRNA) 上调 HNF4α 可以减轻胆固醇毒性 体外，可开发为 AH 的治疗方法。 我们的长期目标是定义以疾病为中心的 AH 途径并开发急需的 AH 患者的治疗。我们假设 HNF4a 依赖性的胆固醇损伤 肝细胞的稳态直接导致 AH 中的肝细胞功能障碍，并且可以作为靶点 治疗上。我们的方法是绘制人类 AH 中胆固醇代谢的调控途径 单细胞分辨率，功能性询问小鼠酒精模型中的胆固醇代谢途径，以及 通过针对 HNF4a 依赖性胆固醇毒性来测试一种新的治疗策略。 目标 1 将使用多模式方法以单细胞分辨率绘制 AH 中的胆固醇代谢图。一个三- 多管齐下的策略将使用单核 RNA 绘制与 AH 相关的胆固醇稳态变化 测序、超高多重成像和靶向空间转录组学。无偏见的参考 图谱将指导细胞和小鼠 AH 模型中胆固醇代谢途径的研究。 目标 2 将定义小鼠模型中胆固醇失调对酒精性肝损伤的影响。 我们将使用长期加酗酒的方式来模拟与 AH 相关的 3 种情况下的胆固醇毒性： (1) 急性胆固醇超负荷，(2) 胆汁酸合成受损，(3) 胆固醇分泌受损 胆汁淤积。这项工作将产生优化的小鼠模型，以概括 AH 中的胆固醇毒性。 目标 3 将评估 HNF4α 依赖性胆固醇毒性途径的靶向操作作为一种新方法 AH 的治疗策略。我们使用 saRNA 调节 HNF4α 亚型表达和胆固醇 代谢。 GalNAc 缀合的 HNF4α-saRNA 将作为肝细胞靶向疗法进行测试 使用分化的人类肝细胞和小鼠模型减轻 AH 模型中的胆固醇毒性。 该项目建立在强大的多学科科学家团队的基础上，结合了独特的专业知识 脂质学、临床前肝脏模型以及最先进的单细胞和空间技术。此次活动的成功 该项目将进一步加深我们对 AH 发病机制的理解，并可能导致新型 AH 的开发 治疗已为临床前和首次人体试验做好准备。