Renal vascular remodeling and arteriogenesis: cues from smooth muscle progenitor cells

肾血管重塑和动脉生成：来自平滑肌祖细胞的线索

基本信息

批准号：
10540412
负责人：
Ondine B Cleaver
金额：
$ 35.25万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-03-01 至 2024-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10540412
关键词：
Ablation Acute Renal Failure with Renal Papillary Necrosis Address Adult Affect American Blood Vessels Blood flow Bypass Cell Differentiation process Cell Lineage Cells Coupling Cues Data Defect Development Dialysis procedure Embryo End stage renal failure Endothelial Cells Endothelium Event Exhibits FOXC1 gene Genetic Goals Growth Health Homeostasis Hypertension Hypoxia Impairment In Vitro Invaded Kidney Kidney Failure Laboratories Laminin Metanephric Diverticulum Modeling Molecular Mus Muscle satellite cell NTN1 gene Nephrons Organ Organogenesis Pattern Perfusion Phenotype Proliferating Proteins Regulation Renal Replacement Therapy Renal Tissue Reporting Role Signal Transduction Smooth Muscle Smooth Muscle Myocytes Specific qualifier value Stromal Cells Survival Rate System Testing Time Transgenic Mice Trees Vascular Smooth Muscle Vascular remodeling angiogenesis cell type in vivo kidney vascular structure mouse model mutant neogenin nephrogenesis nephron progenitor netrin receptor overexpression pharmacologic postnatal receptor renal artery renal hypoxia stem cells transcription factor

项目摘要

SUMMARY Approximately 500,000 Americans have end-stage renal disease. Although organ function can be supplemented using dialysis, the 10-year survival rate is just over 10%. Ex vivo organogenesis has the potential to meet this demand by providing functional tissue for renal replacement therapy. However to effectively generate functional kidneys in the laboratory, all cell types within the kidney and their functional ontogeny and coupling must be understood. Renal blood vessels are one such component that is critical to the health and homeostasis of the kidney. Building the kidney's intricate arterial network requires synchronized actions of endothelial cells (ECs) and vascular smooth muscle cells (vSMCs) in a sequence that is poorly understood. vSMCs arise in the developing kidney from Foxd1+ nephrogenic stromal cells (NSCs). Ablation of Foxd1 or Foxd1+ cells cause similar defects in renal arteries suggesting Foxd1+ NSC encoded signals may govern renal arteriogenesis. We have found that the secreted laminin-like protein Netrin-1 (Ntn1) is expressed by Foxc1+ NSCs in the embryonic kidney. To date, the role of Ntn1 during kidney development has not been reported. Genetic ablation of Ntn1 from Foxd1+ NSCs (hereafter denoted as Ntn1NSCKO) blocks formation of a perfused renal arterial tree during development. In addition, we find Ntn1NSCKO display an aberrant vSMCs-associated cortical vasculature and increased kidney hypoxia. As development proceeds, Ntn1NSCKO also exhibit reduced ureteric bud (UB) branching, and postnatal Ntn1NSCKO mice display delayed nephrogenesis with ~30% fewer glomeruli. Our preliminary data identifies a critical role for Ntn1 in kidney development, but the mechanism(s) of this regulation is unknown. In this proposal, we address this and ask which receptor is needed for kidney formation: stromal-neogenin1, NPC-Unc5b or endothelial-Unc5b? We hypothesize that NSC-derived Ntn1 cell-autonomously directs vSMC lineage specification via its receptor neogenin1 (Neo1) and the transcription factor Klf4, to instruct renal arterial tree assembly, upon which nephron development indirectly depends. We will test this hypothesis by carrying out following aims: 1) We will test the cell autonomy of NSC-derived Ntn1 signaling during renal arterial assembly, by asking how the stroma responds upon absence of Ntn1, where ectopic SMCs come from in the mutants, and which Ntn1 receptors (hence which cell types) are required for arterial development (which recapitulate the Ntn1 phenotype when ablated). 2) We will examine if aberrant nephrogenesis is caused directly via Ntn1 loss in NPCs, or indirectly due to failure of renal arteriogenesis. We will characterize failed nephrogenesis in the Ntn1 mutant kidneys; we will use in vitro systems to see what cell types respond to Ntn1 (NPCs versus ECs); we will test whether late deletion of Ntn1 recapitulates the Ntn1 mutant phenotype, as it bypasses failed arteriogenesis and associated hypoxia; and lastly we will test the role of hypoxia on NPCs directly. 3) We will examine whether Klf4 is required for stromal differentiation and renal arteriogenesis, and whether it signals downstream of Ntn1.

概括大约有50万美国人患有末期肾脏疾病。尽管器官功能可以是使用透析补充的10年生存率刚刚超过10％。离体器官发生有潜力通过为肾脏替代疗法提供功能组织来满足这一需求。但是有效产生实验室中的功能性肾脏，肾脏中的所有细胞类型及其功能性个体发育和耦合必须理解。肾血管是对健康和稳态至关重要的组成部分肾脏。建立肾脏错综复杂的动脉网络需要内皮细胞的同步作用（ECS）和血管平滑肌细胞（VSMC）以鲜为人知的序列。 VSMC在从FOXD1+肾脏基质细胞（NSC）发育肾脏。 FOXD1或FOXD1+细胞的消融导致表明FOXD1+ NSC编码信号的肾动脉中的类似缺陷可能控制肾动脉生成。我们发现，分泌的层粘连蛋白样蛋白Netrin-1（NTN1）在FOXC1+ NSC中表达胚胎肾脏。迄今为止，尚未报道NTN1在肾脏发育中的作用。 FOXD1+ NSC的NTN1的遗传消融（以下称为NTN1NSCKO）阻止了灌注的形成发育过程中的肾动脉树。此外，我们发现NTN1NSCKO显示了与众不同的VSMCS 皮质脉管系统和肾脏缺氧增加。随着发展的进行，NTN1NSCKO也显示出降低输尿管芽（UB）分支和产后NTN1NSCKO小鼠显示出延迟的肾病，较少30％肾小球。我们的初步数据确定了NTN1在肾脏发育中的关键作用，但是该法规未知。在此提案中，我们解决此问题并询问肾脏需要哪种受体形成：基质 - 天内素1，NPC-unc5b或内皮unc5b？我们假设NSC衍生的NTN1细胞自主是通过其指导VSMC谱系规范受体neogenin1（neo1）和转录因子klf4，以指导肾动脉树组装哪些肾脏发育间接取决于。我们将通过执行以下目的来检验这一假设： 1）我们将在肾动脉组装过程中测试NSC衍生的NTN1信号传导的细胞自主权，询问如何基质在不存在NTN1的情况下做出反应，而异位SMC来自突变体中，哪个NTN1 动脉发育需要受体（因此需要哪种细胞类型）（概括了NTN1表型烧毁时）。 2）我们将检查是否通过NPC中的NTN1损失直接引起异常肾病，还是间接由于肾动脉生成的失败。我们将表征NTN1突变体中失败的肾病肾；我们将使用体外系统来查看哪些细胞类型对NTN1（NPCS与ECS）的反应；我们将测试 NTN1的晚期缺失是否概括了NTN1突变体表型，因为它绕过了动脉生成和相关的缺氧；最后，我们将直接测试缺氧对NPC的作用。 3）我们将检查KLF4是否是基质分化和肾动脉生成所必需的，以及它是否在NTN1下游信号。