Extracellular determinants of polycystic kidney disease severity

多囊肾病严重程度的细胞外决定因素

• 批准号: 8479351
• 负责人: MYRON E HINSDALE
• 金额: $ 29.69万
• 依托单位: OKLAHOMA STATE UNIVERSITY STILLWATER
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-15 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8479351
• 关键词: Adult; Aging; Agrin; Anabolism; Animal Model; Animals; Area; Autosomal Recessive Polycystic Kidney; Biliary; Biological Assay; Biology; Caring; Caroli Disease; Cell Proliferation; Cells; Clinical; Complex; Controlled Study; Core Protein; Cyst; Cystic Lesion; Cystic kidney; Data; Development; Disease model; End stage renal failure; Epithelial Cells; Extracellular Matrix; Functional disorder; Gene-Modified; Genetic; Glycosaminoglycans; Goals; Hepatic Cyst; Hyperplasia; Hypertension; Immunohistochemistry; Investigation; Kidney; Kidney Failure; Knowledge; Lead; Lesion; Life; Liver; Liver Fibrosis; Luciferases; Magnetic Resonance Imaging; Measures; Mediating; Methods; Molecular; Morbidity - disease rate; Mus; Mutation; Neonatal; Organ; Outcome; PKD2 protein; Pathogenesis; Pathology; Pathway interactions; Patients; Phenotype; Play; Polycystic Kidney Diseases; Portal Hypertension; Process; Proteinuria; Proteoglycan; Public Health; Regulation; Renal function; Reporter; Research; Research Proposals; Rodent Model; Role; Severities; Severity of illness; Signal Pathway; Signal Transduction; Survivors; Testing; Tissues; Translating; Variant; Wild Type Mouse; base; biliary tract; clinical phenotype; early onset; extracellular; improved; innovation; mortality; mouse model; novel; perlecan; polycystic kidney disease 1 protein; public health relevance; xylosyltransferase

DESCRIPTION (provided by applicant): Little is understood about the genetic modifiers that are responsible for a wide range of complications that afflict autosomal recessive polycystic kidney disease (ARPKD) patients. Understanding what these genetic modifiers are, how they disrupt organ function, and how they aggravate ARPKD, will lead to more effective and tailored therapies aimed at ameliorating patient suffering. Experimental results strongly suggest that reduced proteoglycans (PGs) are modifiers of PKD lesion severity. Therefore, the broad long-term goal of our research group is to identify the responsible PGs and determine their role in the pathogenesis of PKD with the intent of developing targeted treatments that reduce lesion severity. In pursuit of this goal, our investigations have identified several PGs in liver that when lacking glycosaminoglycans are candidates for cyst development. Based on extensive preliminary data, this application's central hypothesis is that reduced PG levels are important modifiers of cyst development and can augment ARPKD cyst development and progression mediated by increased canonical Wnt/?-catenin pathway activity. The overall objective of this application, as a first step towards our long-term goal, is to test this hypothesis with the following aims: 1) To determine the impact of reduced PG on the development of liver and renal cysts in an ARPKD mouse model with decreased FC activity and loss of XylT2 activity. Cyst development, severity, and lesional ?-catenin levels in these mice will be measured using comprehensive histological methods and magnetic resonance imaging; 2) To determine the role that PGs have in renal cyst development by creating adult Xylt2-/- mice that have significantly reduced renal PGs. Renal function, cystic development, and glycosaminoglycan content will be assessed in the resultant mice and compared to controls; 3) To determine the importance of recently identified candidate PGs in the regulation of Wnt/?- catenin signaling in cultured biliary tracts and in isolated biliary epithelial cells. Wild type and Xylt2-/- cells and biliary tracts will be cultured under conditions of increased Wnt/?-catenin activation in the presence of core protein with and without glycosaminoglycans. Wnt/?-catenin signaling will be assessed by luciferase reporter assays and by immunohistochemistry for pathway intermediates and correlated with cellular proliferation and cyst development. The rationale of the proposed research is based on the assumption that understanding the molecular mechanism of ARPKD lesion modifiers will translate into fundamental improvements in understanding PKD lesion development. Thus the proposed research is relevant to PA-07- 293 in regards to defining "the function of molecules and pathways that cause, aggravate or ameliorate PKD" and identifying "in rodent models...specific genes that modify the clinical phenotype." The proposed research is significant because the identification of genetic modifiers and understanding their impact on clinical variation is expected to advance individualized ARPKD patient treatment and prognostication.

描述（由申请人提供）：关于造成多种并发症的遗传修饰剂，几乎没有理解，这些并发症会困扰常染色体隐性遗传性多囊性肾脏病（ARPKD）患者。了解这些遗传修饰剂是什么，它们如何破坏器官功能以及如何加重ARPKD，将导致更有效和量身定制的疗法，以减轻患者的痛苦。实验结果强烈表明蛋白聚糖降低（PGS）是PKD病变严重程度的修饰符。因此，我们研究小组的广泛长期目标是确定负责任的PG并确定其在PKD发病机理中的作用，目的是开发降低病变严重程度的靶向治疗方法。为了实现这一目标，我们的调查已经确定了肝脏中的几个PG，当缺乏糖胺聚糖时，是囊肿开发的候选者。基于广泛的初步数据，该应用程序的中心假设是，降低的PG水平是囊肿发育的重要修饰符，并且可以增强ARPKD囊肿的发展和由Catenin pathway途径增加而介导的介导的ARPKD囊肿的发展和进展。作为我们长期目标的第一步，该应用的总体目标是以以下目的检验该假设：1）确定PG减少对ARPKD小鼠模型中FC活性降低和Xylt2活性损失的肝脏和肾囊肿的影响。这些小鼠的囊肿发育，严重程度和病变水平将使用全面的组织学方法和磁共振成像来测量； 2）通过创建成年Xylt2 - / - 小鼠，确定PG在肾囊肿发育中的作用，这些小鼠显着降低了肾脏PG。将在由此产生的小鼠中评估肾功能，囊性发育和糖胺聚糖含量，并将其与对照组进行比较。 3）确定最近确定的候选PG在培养的胆道和分离的胆道上皮细胞中的Wnt/？ - catenin信号传导中的重要性。野生型和xylt2 - / - 细胞和胆道将在有或没有糖胺聚糖的核心蛋白存在下培养在Wnt/？ - catenin激活的条件下。 Wnt/？ - Catenin信号传导将通过荧光素酶报告基因测定法和免疫组织化学进行途径中间体评估，并与细胞增殖和囊肿发育相关。拟议研究的基本原理是基于这样的假设：了解ARPKD病变修饰剂的分子机制将转化为理解PKD病变发展的基本改善。因此，提出的研究与PA-07-293有关，在定义“导致，加重或改善PKD的分子和途径的功能”方面，并识别“在啮齿动物模型中……修改临床表型的特定基因”。拟议的研究很重要，因为鉴定遗传修饰剂并了解其对临床变异的影响有望推动个性化的ARPKD患者治疗和预后。