REGULATORS OF CALCINEURIN PATHWAYS AS DIAGNOSTIC AND THERAPEUTIC TARGETS FOR NEPHROTIC SYNDROME

钙调磷酸酶途径的调节剂作为肾病综合征的诊断和治疗目标

• 批准号: 10560239
• 负责人: Rasheed Adebayo Gbadegesin
• 金额: $ 71.33万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-01 至 2026-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10560239
• 关键词: Apoptosis; Biological Markers; Biotechnology; Calcineurin; Calcineurin Pathway; Calcineurin inhibitor; Cells; Chronic Kidney Failure; Clinical; Clustered Regularly Interspaced Short Palindromic Repeats; Custom; Cytoskeleton; Data; Defect; Diagnostic; Disease; Disease remission; Drug Targeting; Economics; Family; Genes; Genetic; Genetic Determinism; Genetic Predisposition to Disease; Genetic Transcription; Heterozygote; Homeostasis; Individual; Injury; Kidney; Kidney Diseases; Knowledge; Mediating; Molecular; Mutation; Nephrotic Syndrome; Organoids; Participant; Pathogenesis; Pathogenicity; Pathologic; Patient Care; Patients; Pharmaceutical Preparations; Phenotype; Prediction of Response to Therapy; Prevalence; Process; Protein Dephosphorylation; Proteins; Regulator Genes; Renal glomerular disease; Role; Signal Pathway; Signal Transduction; Steroid-resistant idiopathic nephrotic syndrome; Testing; Therapeutic; Toxic effect; United States; Variant; biomarker identification; cellular targeting; cohort; cost; diagnostic tool; effective therapy; genome sequencing; induced pluripotent stem cell; inhibitor; inhibitor therapy; kidney biopsy; multi-ethnic; mutant; nephrotoxicity; new therapeutic target; next generation sequencing; noninvasive diagnosis; novel; pharmacologic; podocyte; predicting response; rare variant; response; response biomarker; screening; segregation; side effect; success; targeted treatment; therapeutic target; transcriptomics; treatment response; whole genome

Nephrotic syndrome and other glomerular diseases are major causes of chronic kidney diseases world-wide. The molecular mechanisms of NS are not completely known, and this major gap in knowledge is an impediment to treating patients with NS and developing new treatments. A more complete understanding of the mechanisms underlying NS is critical for identification of robust non-invasive diagnostic tools and precise effective treatment options. In preliminary data, we identified pathogenic variants in the genes regulator of calcineurin (CN) types 1- 3 (RCAN1-3) in patients with NS. We showed that cells expressing mutant RCAN1 displayed elevated CN activity and increased apoptosis. These phenotypes were rescued by pharmacological inhibition of CN. Our findings suggest that variants in RCAN genes are novel genetic causes of NS, and that modulators of CN signaling may represent targeted therapy for individuals with NS induced by RCAN mutations, the more common idiopathic NS and other glomerular diseases. Despite the fact, that unregulated CN activation is central to the pathogenesis of multiple glomerular disease processes and CN inhibitors (CNIs) are often used for treatment, the signaling pathways regulated by RCAN proteins specifically are not well understood. Further, only ~30-50% of patients with steroid resistant NS will achieve remission with CNI treatment and there are currently no biomarkers to predict therapy response despite major side effects of CNI including nephrotoxicity. The overarching hypothesis of this study is that genetic defects in RCAN genes cause CNI responsive NS by reducing podocyte viability due to aberrant cytoskeletal dynamics that can be ameliorated by targeting modulators of RCAN activity. We will test our hypothesis through the following aims: 1) Determine the effect of pathogenic variants in RCAN genes on CNI therapy response in patients with NS, 2) Determine the molecular mechanisms mediating the aberrant phenotypes caused by pathogenic RCAN variants in patient derived iPSC podocytes and iPSC-kidney organoids, and 3) Identify targeted therapies that can rescue the aberrant RCAN phenotypes in ex-vivo podocytes. Data generated from these studies will define the role of genetic defects in RCAN genes in disease pathogenesis and CNI therapy response in patients with NS. In addition, the study will reveal podocyte signaling mechanisms that are dysregulated due to defective RCAN genes and ultimately lead to identification of novel or repurposed therapeutic alternatives to CNI treatment.

肾病综合征和其他肾小球疾病是全世界慢性肾脏疾病的主要原因。 NS 的分子机制尚不完全清楚，这一知识上的重大差距是一个障碍 治疗 NS 患者并开发新的治疗方法。对机制有更全面的了解 潜在的 NS 对于确定强大的非侵入性诊断工具和精确有效的治疗至关重要 选项。在初步数据中，我们鉴定了 1- 型钙调神经磷酸酶 (CN) 基因调节因子的致病性变异。 NS 患者中的 3 (RCAN1-3)。我们发现表达突变体 RCAN1 的细胞表现出升高的 CN 活性 并增加细胞凋亡。这些表型可以通过 CN 的药理学抑制来挽救。我们的发现 表明 RCAN 基因变异是 NS 的新遗传原因，CN 信号调节剂可能 代表针对由 RCAN 突变引起的 NS 个体的靶向治疗，即更常见的特发性 NS 和其他肾小球疾病。尽管如此，不受调控的 CN 激活是疾病发病机制的核心。 多种肾小球疾病过程和 CN 抑制剂 (CNI) 经常用于治疗，信号传导 RCAN 蛋白具体调节的途径尚不清楚。此外，只有约 30-50% 的患者 患有类固醇耐药的 NS 将通过 CNI 治疗获得缓解，目前没有生物标志物 尽管 CNI 存在主要副作用（包括肾毒性），但仍可预测治疗反应。总体假设 这项研究的重点是，RCAN 基因的遗传缺陷通过降低足细胞活力而导致 CNI 反应性 NS 异常的细胞骨架动力学可以通过靶向 RCAN 活性调节剂来改善。我们将测试 我们的假设通过以下目标： 1) 确定 RCAN 基因致病变异对 CNI 的影响 NS 患者的治疗反应，2) 确定介导异常的分子机制 患者来源的 iPSC 足细胞和 iPSC 肾脏中致病性 RCAN 变异引起的表型 类器官，以及 3) 确定可以挽救离体异常 RCAN 表型的靶向疗法 足细胞。这些研究产生的数据将定义 RCAN 基因遗传缺陷在疾病中的作用 NS 患者的发病机制和 CNI 治疗反应。此外，该研究还将揭示足细胞信号传导 由于 RCAN 基因缺陷而失调的机制，最终导致识别新的或 重新调整 CNI 治疗的替代治疗方案。