Autocrine and paracrine podocyte signals decrease glomerular function/health in aged kidneys

自分泌和旁分泌足细胞信号会降低老年肾脏的肾小球功能/健康

• 批准号: 10698100
• 负责人: Stuart James Shankland
• 金额: $ 73.57万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-15 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10698100
• 关键词: Acceleration; Address; Age; Aging; Cell Aging; Cells; Cicatrix; Coculture Techniques; Data; Data Set; Deposition; Devices; Dialysis procedure; Disease; Disease Outcome; Elderly; Epithelial Cells; Exhibits; Experimental Designs; Extracellular Matrix Proteins; Face; Feasibility Studies; Feedback; Gene Expression; Genetic; Glomerular Filtration Rate; Goals; Grant; Health; Human; Hypertrophy; Immune response; Impairment; Individual; Inflammasome; Inflammation; Inflammation Mediators; Inflammatory; Interferons; Interleukins; Kidney; Kidney Diseases; Knowledge; Life; Life Expectancy; Ligands; Longevity; Methodology; Modeling; Mus; Nuclear; Operative Surgical Procedures; Outcome; PD-1 pathway; Parietal; Pathway interactions; Patients; Phenotype; Physiology; Play; Population; Process; Proteins; Public Health; Publishing; Regulation; Renal Mass; Renal function; Renal glomerular disease; Reporting; Research; Role; Signal Transduction; Source; Stress; Structure; Surface; TNF gene; Testing; Therapeutic; Thinking; Time; Toll-like receptors; Transcript; Transgenic Mice; age related; aged; autocrine; cell type; chemokine; cytokine; extracellular; gene function; glomerular function; glomerulosclerosis; healthspan; inhibitor; innovation; kidney biopsy; mouse model; novel; older patient; paracrine; podocyte; postmitotic; programmed cell death protein 1; receptor; response; senescence; transcriptome; transcriptome sequencing; transcriptomics; translational impact

PROJECT SUMMARY/ABSTRACT The overall scope of the problem is that as the US population lives longer, kidney disease becomes more abundant. In particular, elderly patients face worse disease outcomes, and they are now the largest group to undergo first-time dialysis. The goal of this proposal is to prove that aged podocytes are central to the many glomerular changes with aging. Changes to and loss of podocytes remain the best predictors of age-related glomerulosclerosis and reduced GFR. Major unmet needs are understanding the mechanisms of podocyte aging and the crosstalk between aged podocytes and neighboring parietal epithelial cells (PECs). To close these knowledge gaps, we performed a transcriptome analysis comparing podocytes from aged vs. young mice. Much to our surprise, transcripts for immune response processes such as inflammasome components, inflammatory factors (e.g. TNFα, interferons, interleukins and chemokines) and SASPs were significantly enriched. Importantly, similar changes were confirmed in human kidney biopsies. Based on these preliminary data, we propose a novel paradigm that aged podocytes secrete inflammatory signals and SASPs that in autocrine loops directly impact podocytes themselves. Specific Aim #1 will prove that this newly discovered inflammatory aged podocyte phenotype directly shortens the podocyte's lifespan and reduces their health-span. We will test the hypotheses that in aged podocytes: (1) Inflammasome-induced de novo intracellular inflammation reduces podocyte lifespan; (2) The PD1 signaling pathway acts downstream of the NLRP3 inflammasome; (3) A specific subset of secreted inflammatory mediators accelerates the podocyte aging phenotype through autocrine loops. We also propose a second novel paradigm in which aged podocytes play a paracrine role in accelerating PEC aging. This is based on the facts that (i) podocyte aging temporally precedes PEC aging; (ii) PEC aging is typically only present in individual glomeruli in which podocytes exhibit an aged phenotype; (iii) inhibition of the inflammasome or PD1 pathways in aged podocytes reduces PEC aging. In Specific Aim #2 we propose that SASPs and inflammatory cytokines derived from aged podocytes accelerate the PEC aging phenotype through paracrine loops. We will test the hypotheses that: (1) The inflammatory podocyte phenotypes in aged mice precedes and accelerates PEC aging. (2) A distinct subset of SASPs and inflammatory cytokines derived from aged podocytes accelerates the PEC aging phenotype. These studies are based on many innovative experimental approaches including aging studies in transgenic mice, primary human podocytes and PECs, Design-of-Experiment methodology and novel co-culture models. Finally, the focus of our study is significant for its short-term translational impact by intersecting our mouse data with a large transcriptomic data set on aged human kidneys and its long-term impact in developing therapeutic strategies that will counter the age-dependent demise of kidney function.

项目概要/摘要 问题的总体范围是，随着美国人寿命的延长，肾脏疾病变得更加严重 丰富。特别是老年患者面临着更严重的疾病结局，他们现在是最大的群体 进行首次透析。该提案的目标是证明衰老的足细胞是许多足细胞的核心 肾小球随着年龄的增长而变化。足细胞的变化和丧失仍然是年龄相关的最佳预测因素 肾小球硬化和 GFR 降低。主要未满足的需求是了解足细胞的机制 衰老以及衰老的足细胞和邻近的壁上皮细胞（PEC）之间的串扰。关闭 针对这些知识差距，我们进行了转录组分析，比较了老年人和年轻人的足细胞 老鼠。令我们惊讶的是，免疫反应过程的转录本，例如炎性体成分， 炎症因子（例如 TNFα、干扰素、白细胞介素和趋化因子）和 SASP 显着 丰富了。重要的是，在人类肾脏活检中也证实了类似的变化。 基于这些初步数据，我们提出了一种新的范例，即衰老的足细胞分泌炎症 自分泌环路中的信号和 SASP 直接影响足细胞本身。具体目标#1 将证明 这种新发现的炎症老化足细胞表型直接缩短足细胞的寿命 并缩短他们的健康寿命。我们将在衰老的足细胞中测试以下假设：（1）炎症小体诱导的 从头开始的细胞内炎症会缩短足细胞的寿命； (2) PD1信号通路作用于下游 NLRP3 炎性体； (3) 分泌性炎症介质的特定子集加速了 通过自分泌环的足细胞老化表型。 我们还提出了第二种新范式，其中老化的足细胞在加速中发挥旁分泌作用 PEC老化。这是基于以下事实：(i) 足细胞老化暂时先于 PEC 老化； (ii) PEC老化是 通常仅存在于单个肾小球中，其中足细胞表现出老化表型； (iii) 抑制 老化足细胞中的炎性体或 PD1 通路可减少 PEC 老化。在具体目标#2 中，我们建议 来自老化足细胞的 SASP 和炎症细胞因子通过以下方式加速 PEC 老化表型： 旁分泌环。我们将检验以下假设：（1）老年小鼠的炎症足细胞表型 先于并加速 PEC 老化。 (2) SASP 和炎症细胞因子的一个独特子集，源自 老化的足细胞加速了 PEC 的老化表型。 这些研究基于许多创新的实验方法，包括转基因衰老研究 小鼠、原代人类足细胞和 PEC、实验设计方法和新颖的共培养模型。 最后，我们研究的重点是通过与我们的鼠标相交来对其短期翻译影响具有重要意义 包含有关老年人肾脏的大量转录组数据及其对发育的长期影响 对抗年龄依赖性肾功能衰竭的治疗策略。