ATP Binding Cassette Transporters in Health and Disease

健康和疾病中的 ATP 结合盒转运蛋白

• 批准号: 10552563
• 负责人: Elizabeth Joanna Tarling
• 金额: $ 60.81万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-09 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10552563
• 关键词: ATP-Binding Cassette Transporters; Acute; Address; Adult; Alcohol consumption; Animals; Bile Acids; Bile fluid; Biliary; CRISPR/Cas technology; Cannulations; Cause of Death; Cholestasis; Classification; Clustered Regularly Interspaced Short Palindromic Repeats; Defect; Development; Disease; Disease Progression; Embryo; Enzymes; Event; Fibrosis; Functional disorder; Gene Expression; Genes; Health; Health system; Hepatic; Hepatomegaly; Histologic; Histopathology; Human; Hybrids; Impairment; Inbred Strains Mice; Lipids; Liver; Liver diseases; Measures; Metabolic; Metabolism; Methods; Molecular; Mus; Nutrient; Onset of illness; Pathogenesis; Pathogenicity; Pathology; Pathway interactions; Physiological Processes; Plasma; Progressive intrahepatic cholestasis; Proteins; Proteomics; Public Health; Regulation; Reporting; Resistance; Role; Systems Biology; Testing; Therapeutic Intervention; Triglycerides; Very Long Chain Fatty Acid; Virus Diseases; Wild Type Mouse; bile acid metabolism; branched chain fatty acid; chronic liver disease; design; disorder prevention; effective therapy; in vitro Assay; in vivo; lipid metabolism; lipid transport; lipidome; lipidomics; liver injury; loss of function; non-alcoholic fatty liver disease; nonalcoholic steatohepatitis; novel; peroxisome; prevent; protein expression; tool; western diet

ABSTRACT Metabolic and chronic liver diseases are among the leading causes of death in the US. The liver is a central hub that coordinately regulates the metabolism of many nutrients, including lipids. The liver does not store lipids in the long-term, and lipid accumulation in the liver results in different diseases. Triglyceride accumulation in the liver causes steatosis which can progress to non-alcoholic steatohepatitis (NASH), both part of the non-alcoholic fatty liver disease (NAFLD) spectrum. Accumulation of bile acids in the liver because of viral infections, alcohol use or more advanced liver damage causes cholestasis. Identification of the molecular mechanisms of specific disease-promoting pathways is an essential step before pathways can be safely targeted for disease prevention. Our studies will further the understanding of the role of peroxisomal ABCD transporters in the liver. We have used an unbiased systems biology approach to identify new players in the regulation of lipid metabolism in the liver. Through these methods, we identified the peroxisomal transporter ABCD3 as a novel regulator of hepatic lipid metabolism. Abcd3−/− mice are partially lethal and loss of ABCD3 in surviving animals alters the hepatic lipidome and results in hepatomegaly and profoundly reduced biliary bile acids. To study ABCD3 in vivo, we have developed and validated a novel AAV-CRISPR strategy to disrupt Abcd3 exclusively in the liver, allowing us to disrupt Abcd3 in adult wild-type mice in a temporal fashion to determine the sequelae of events leading to the defects observed after loss of ABCD3. Using these tools, we show that acute loss of hepatic ABCD3 in adult mice is sufficient to recapitulate the dramatic reduction in biliary bile acids. When fed a Western diet (WD), loss of hepatic ABCD3 results in liver lipid accumulation as well as elevated plasma liver enzymes and bile acids, all hallmarks of NASH. We have designed two specific aims; in Aim 1 we will test the hypothesis that ABCD3 deficiency results in cholestasis and NASH. In Aim 2, we will identify specific substrates for ABCD3 and test the hypothesis that peroxisomal lipid defects are pathogenic and key for the development of NASH. Our studies demonstrate that loss of ABCD3, which is lethal in humans, results in cholestasis and NASH in a setting of elevated lipid levels. Completion of these studies will further the understanding of the role of peroxisomal ABCD transporters in the liver, and implicate peroxisomal lipid metabolism as an important contributor in the pathogenesis of NASH.

抽象的 代谢性和慢性肝病是美国的主要原因之一。肝脏是中枢 它协调调节许多营养物质的代谢，包括脂质。肝脏不储存脂质 长期而言，肝脏中的脂质堆积会导致不同的疾病。甘油三酯在体内蓄积 肝脏引起脂肪变性，可进展为非酒精性脂肪性肝炎 (NASH)，两者都是非酒精性脂肪性肝炎的一部分 脂肪肝疾病（NAFLD）谱系。由于病毒感染、酒精导致胆汁酸在肝脏中积聚 使用或更严重的肝损伤会导致胆汁淤积。特定分子机制的鉴定 在安全地针对疾病预防途径之前，确定促进疾病的途径是至关重要的一步。 我们的研究将进一步了解过氧化物酶体 ABCD 转运蛋白在肝脏中的作用。我们有 使用公正的系统生物学方法来识别脂质代谢调节中的新参与者 肝。通过这些方法，我们确定了过氧化物酶体转运蛋白 ABCD3 作为肝细胞的新型调节剂。 脂质代谢。 Abcd3−/− 小鼠部分致死，幸存动物中 ABCD3 的丧失会改变肝脏 脂质组并导致肝肿大和胆汁胆汁酸显着降低。为了在体内研究 ABCD3，我们 开发并验证了一种新的 AAV-CRISPR 策略，可以仅在肝脏中破坏 Abcd3，从而允许 我们以暂时的方式破坏成年野生型小鼠的 Abcd3 以确定导致以下事件的后遗症 ABCD3 缺失后观察到的缺陷。使用这些工具，我们表明成人肝脏 ABCD3 的急性丢失 小鼠足以重现胆汁酸的急剧减少。当喂食西方饮食（WD）时，损失 肝脏 ABCD3 的减少会导致肝脏脂质积累以及血浆肝酶和胆汁酸升高，所有这些 NASH 的特征。我们设计了两个具体目标；在目标 1 中，我们将检验假设 ABCD3 缺乏会导致胆汁淤积和 NASH。在目标 2 中，我们将鉴定 ABCD3 的特定底物并测试 假设过氧化物酶体脂质缺陷是 NASH 发病的致病因素和关键。我们的研究 证明ABCD3（对人类致命）的缺失会导致胆汁淤积和NASH 血脂水平升高。这些研究的完成将进一步了解过氧化物酶体 ABCD 的作用 肝脏中的转运蛋白，并表明过氧化物酶体脂质代谢是肝脏中的重要贡献者 NASH 的发病机制。