ENTPD1: A Candidate Susceptibility Gene for Renovascular Disease

描述(由申请人提供)： 糖尿病肾病是美国肾功能衰竭的主要原因，它是肾微血管损伤的结果。在这项建议中，我们使用啮齿动物模型来研究ENTPD1(也被称为CD39)在肾血管疾病，特别是糖尿病肾病中的保护作用。 ENTPD1是一种血管外切核苷酸酶，能将ATP和ADP水解为AMP，从而通过嘌呤能受体调节胞外核苷酸信号转导。在几种急性和亚急性血管损伤模型中，ENTPD1是一种保护因子。我们假设ENTPD1在保护糖尿病患者肾脏血管免受慢性损伤方面起着至关重要的作用。我们还预测，在长期研究的肾功能衰竭大鼠模型中，难以捉摸的突变基因是ENTPD1。 在目标1中，我们利用ENTPD1基因缺失或转基因的小鼠，在慢性血管损伤模型中表征ENTPD1在血管保护中的作用。通过识别核苷酸信号异常驱动的损伤下游通路，我们将开始了解ENTP1‘S对糖尿病损伤保护作用的机制。在目标2中，我们的目标是证明ENTPD1酶活性降低会在小鼠模型中产生肾血流自动调节的缺陷。这些缺陷也与糖尿病患者肾损害的发生有关。在目标3中，我们建立了证据表明，ENTPD1的突变导致了大鼠肾脏损伤的一个强大的数量性状基因座(QTL)。我们提出了酶活性分析、分子遗传学和活体挽救实验来证明这一猜想。 这项研究将主要在贝丝以色列女执事医学中心和哈佛医学院的西蒙·罗布森的实验室进行，西蒙·罗布森是研究电子核酸酶和嘌呤能信号转导的先驱。申请者将在美国国立卫生研究院于尔根·施纳曼医学博士的实验室进行额外的生理学实验。申请者的培训和职业发展将通过课程作业、会议、研讨会系列和其他活动在这个激动人心的学术环境中得到加强。 申请者是一名经过委员会认证的肾脏科医生，对科学充满热情，并坚定地致力于转化性研究。这项冒险但有重点的研究提案和培训计划将为申请人向独立过渡到研究医学职业生涯做好准备。 该项目的长期科学目标是了解ENTPD1可能如何影响糖尿病患者的肾脏疾病。我们的发现最终可能导致对这种毁灭性的糖尿病并发症的早期诊断和治疗。

DESCRIPTION (provided by applicant): Diabetic nephropathy, the leading cause of renal failure in the United States, results from injury to the renal microvasculature. In this proposal, we use rodent models to investigate the protective role of ENTPD1 (also known as CD39) in renovascular disease, particularly diabetic nephropathy. ENTPD1 is a vascular ectonucleotidase that hydrolyzes ATP and ADP to AMP, thereby modulating extracellular nucleotide signaling via purinergic receptors. ENTPD1 is a protective factor in several models of acute and sub-acute vascular injury. We hypothesize that ENTPD1 is crucial in protecting the renal vasculature from chronic injury in diabetes. We also predict that the elusive mutant gene in a long-studied rat model of renal failure is ENTPD1. In Aim 1, we characterize the role of ENTPD1 in vascular protection in models of chronic vascular injury using mice null or transgenic for ENTPD1. By identifying the downstream pathways of injury driven by aberrant nucleotide signaling, we will begin to understand the mechanisms explaining ENTP1's protective effects against diabetic injury. In Aim 2, our goal is to show that reduced ENTPD1 enzymatic activity produces defects in autoregulation of renal blood flow in mouse models. Such defects are also associated with development of renal impairment in patients with diabetes. In Aim 3, we build evidence that a powerful Quantitative Trait Locus (QTL) for renal injury in rats is caused by a mutation in ENTPD1. We propose enzymatic activity assays, molecular genetics, and in vivo rescue experiments to prove this conjecture. This research will be performed predominantly at Beth Israel Deaconess Medical Center and Harvard Medical School in the lab of Simon Robson, M.D., Ph.D., a pioneer in the study of ectonucleotidases and purinergic signaling. Additional physiologic experiments will be performed by the applicant at the NIH in the laboratory of Jurgen Schnermann, M.D. The applicant's training and career development will be enhanced by coursework, conferences, seminar series, and other events in this stimulating academic environment. The applicant is a board-certified nephrologist with a passion for science and a firm commitment to translational research. This adventurous but focused research proposal and training plan will prepare the applicant for the transition to independence for a career in investigational medicine. The long-term scientific goal of this project is to understand how ENTPD1 might impact kidney disease in patients with diabetes. Our findings could eventually lead to early diagnosis and treatment of this devastating complication of diabetes.