Role of Fumarate and Nrf2 response in the pathogenesis of Autosomal Dominant Polycystic Kidney Disease

富马酸和 Nrf2 反应在常染色体显性多囊肾发病机制中的作用

• 批准号: 9583066
• 负责人: Maria V Irazabal
• 金额: $ 19.88万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9583066
• 关键词: Abnormal Epithelial Cell; Address; Age; Animals; Antioxidants; Apoptosis; Autosomal Dominant Polycystic Kidney; Bilateral; Biological Assay; Biological Markers; Birth; Carbon; Cell Proliferation; Cell Survival; Cells; Cellular Stress; Chemical Models; Citric Acid Cycle; Classification; Clinical; Cyst; Cysteine; Cystic kidney; Data; Development; Disease; Disease Pathway; Disease Progression; End stage renal failure; Enzymes; Epithelial Cell Proliferation; Erythroid; Exhibits; FDA approved; Fibrosis; Fumarate Hydratase; Fumarate Hydratase Deficiency; Fumarates; Functional disorder; Gender; Genetic Diseases; Genetic Engineering; Glutamine; Hereditary Leiomyomatosis and Renal Cell Cancer; Image; Imaging Techniques; Kidney; Kidney Failure; Label; Laboratory Animals; Lead; Measures; Metabolic Pathway; Metabolism; Modeling; Mus; NMR Spectroscopy; Nordihydroguaiaretic Acid; Nuclear; Pathogenesis; Patients; Phenols; Plasma; Production; Proteins; Rattus; Registries; Renal Cell Carcinoma; Renal Replacement Therapy; Renal Tissue; Rodent Model; Role; Severity of illness; Signal Transduction; Source; Stress; Superoxide Dismutase; Supportive care; Techniques; Testing; Therapeutic Intervention; Time; Tissues; Transcriptional Activation; Ubiquitination; Up-Regulation; Urine; Western Blotting; biomarker discovery; early detection biomarkers; heme oxygenase-1; indexing; liquid chromatography mass spectrometry; metabolic profile; metabolomics; novel; novel marker; response; spectroscopic imaging; stable isotope; targeted treatment; therapeutic target; transcription factor; urea cycle; urinary; volunteer

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a multisystem devastating disease, characterized by multiple bilateral renal cysts, renal complications, and progression to end-stage renal disease. Abnormal epithelial cell proliferation, a distinctive feature in PKD, underlies cyst formation and enlargement. Therefore, identifying dysregulations in the cellular mechanisms known to promote cell proliferation represents a major opportunity for therapeutic interventions. The Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a transcription factor that regulates cellular protection against stress and survival by modulating the expression of antioxidant proteins. Phenolic compounds like nordihydroguaiaretic acid (NDGA) interfere with Nrf2 ubiquitination, favoring its transcriptional activation. NDGA is known to cause cystogenesis in non-PKD rats. Fumarate is a citric acid cycle (TCA) and urea cycle intermediate that can also modulate Nrf2 ubiquitination. Increased fumarate has been associated with cystogenesis and renal cell cancer in fumarate hydratase (FH) deficiency. In preliminary studies we have discovered an increase in fumarate levels in PKD deficient cells. What is more, our studies in early stage PKD rats (PCK) discovered increased urinary and renal tissue fumarate compared to wild-type (WT) rats. In addition, urinary and renal tissue fumarate levels were higher in Pkd1RC/RC mice compared to controls, and positively correlated with disease severity (cystic index and fibrosis). Notably, renal expression of nuclear Nrf2 was higher in Pkd1RC/RC mice compared to controls. Finally, urine from young patients with ADPKD had increased levels of fumarate compared to normal volunteers. However, whether increased fumarate levels in the context of PKD contribute to a dysregulation in the Nrf2 response, ultimately promoting cystogenesis has never been explored. The hypothesis underlying this proposal is that ADPKD results in increased levels of fumarate and that this increase results in upregulation of Nrf2 signaling leading to cellular proliferation and contributing to cystogenesis. Hence, determining the origin of the increase in fumarate would uncover metabolic pathways altered in ADPKD that could help identifying novel disease biomarkers and developing targeted therapeutic interventions. To test this hypothesis we will take advantage of genetically engineered rodent models, our previously developed imaging classification of ADPKD, and state of the art spectroscopic techniques as well as unique stable isotope metabolomics and spectroscopic imaging techniques. Three specific aims will be pursued: Specific Aim 1 will test the hypothesis that cystogenesis in orthologous models of ADPKD is accompanied by altered metabolomics and increased levels of fumarate that leads to up regulation of Nrf2 signaling and cystogenesis. Specific Aim 2 will test the hypothesis that fumarate levels and Nrf2 response are increased in patients with ADPKD and correlate with disease severity. Specific Aim 3 will test the hypothesis that the increased levels of fumarate in kidneys and urines of patients and rodent models of ADPKD result from dysregulation of TCA cycle, glutamine metabolism, or the urea cycle and fumarate hydratase activity. Successful studies will have important clinical implications by advancing understanding of the pathophysiology of the disease, identifying novel early biomarkers, and highlighting additional metabolic pathways that could be targeted for therapeutic intervention in a disease with no specific treatment available.

常染色体显性多囊肾病（ADPKD）是一种多系统破坏性疾病， 其特点是多发性双侧肾囊肿、肾脏并发症以及进展为终末期肾病。 异常上皮细胞增殖是 PKD 的一个显着特征，是囊肿形成和扩大的基础。 因此，识别已知促进细胞增殖的细胞机制中的失调代表 治疗干预的一个重要机会。核因子（红细胞衍生 2）样 2 (Nrf2) 是一种 通过调节表达来调节细胞抗应激和生存保护的转录因子 抗氧化蛋白质。去甲二氢愈创木酸 (NDGA) 等酚类化合物会干扰 Nrf2 泛素化，有利于其转录激活。 NDGA 已知会导致非 PKD 大鼠的囊肿发生。 富马酸是柠檬酸循环 (TCA) 和尿素循环中间体，也可以调节 Nrf2 泛素化。 富马酸水合酶 (FH) 中富马酸的增加与囊肿发生和肾细胞癌有关 不足。在初步研究中，我们发现 PKD 缺陷细胞中富马酸水平增加。 更重要的是，我们对早期 PKD 大鼠 (PCK) 的研究发现泌尿和肾组织增加 富马酸与野生型（WT）大鼠相比。此外，尿和肾组织中富马酸盐水平较高 Pkd1RC/RC 小鼠与对照组相比，与疾病严重程度（囊肿指数和纤维化）呈正相关。 值得注意的是，与对照组相比，Pkd1RC/RC 小鼠的肾 Nrf2 核表达更高。最后是尿液 与正常志愿者相比，患有 ADPKD 的年轻患者的富马酸水平升高。然而， PKD 背景下富马酸水平升高是否会导致 Nrf2 反应失调， 最终促进囊肿发生尚未被探索过。该提案的假设是 ADPKD 导致富马酸水平增加，并且这种增加导致 Nrf2 信号传导上调 导致细胞增殖并促进囊肿发生。因此，确定增加的来源 富马酸盐将揭示 ADPKD 中代谢途径的改变，有助于识别新疾病 生物标志物和开发有针对性的治疗干预措施。为了检验这个假设，我们将利用 基因工程啮齿动物模型、我们之前开发的 ADPKD 影像学分类以及 ADPKD 的状态 先进的光谱技术以及独特的稳定同位素代谢组学和光谱成像 技术。将追求三个具体目标： 具体目标 1 将检验以下假设： ADPKD 的直系同源模型伴随着代谢组学的改变和富马酸水平的增加， 导致 Nrf2 信号传导和囊肿发生的上调。具体目标 2 将检验富马酸盐的假设 ADPKD 患者的 Nrf2 水平和 Nrf2 反应增加，并且与疾病严重程度相关。具体的 目标 3 将检验以下假设：患者和啮齿动物的肾脏和尿液中富马酸盐水平升高 ADPKD 模型是由 TCA 循环、谷氨酰胺代谢或尿素循环失调引起的 富马酸水合酶活性。成功的研究将通过推进具有重要的临床意义 了解疾病的病理生理学，识别新的早期生物标志物，并强调 可以针对没有特定疾病的治疗干预的其他代谢途径 可以治疗。