Targeting pathologic G-protein signaling in cardiac and kidney fibrosis

靶向心脏和肾脏纤维化中的病理性 G 蛋白信号传导

• 批准号: 9169956
• 负责人: Burns C Blaxall
• 金额: $ 48.36万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9169956
• 关键词: Ablation; Acute; Address; Agonist; Attenuated; Biological Assay; Breeding; Cardiac; Cardiac Myocytes; Cardiovascular Diseases; Cardiovascular Pathology; Cells; Characteristics; Chronic; Deposition; Disease; Disease Progression; Endothelin; Endothelin-2; Epithelial Cells; Extracellular Matrix; FDA approved; Failure; Fibroblasts; Fibrosis; Functional disorder; G protein coupled receptor kinase; G-Protein-Coupled Receptors; GTP-Binding Proteins; Genetic; Heart; Heart failure; Human; Injury; Ischemia; Kidney; Kidney Failure; Knock-in Mouse; Knockout Mice; Lead; Mechanics; Mediator of activation protein; Membrane; Molecular; Mus; Myocardial Ischemia; Myocardial dysfunction; Myofibroblast; Organ; Outcome; Pathologic; Patients; Pericytes; Phosphotransferases; Play; Public Health; Reagent; Recruitment Activity; Renal function; Reperfusion Injury; Reperfusion Therapy; Rodent; Role; Signal Transduction; Specificity; Syndrome; Therapeutic; Tissues; Treatment Efficacy; United States; Up-Regulation; Ventricular; base; constriction; coronary fibrosis; gallein; in vivo; inhibitor/antagonist; interstitial; mortality; mouse model; new therapeutic target; novel; outcome forecast; protective effect; renal ischemia; response; small molecule; targeted treatment; therapeutic target

Summary: Fibrosis is a key component of pathologic remodeling in multiple tissues, no therapies specifically target maladaptive fibrosis. Heart failure (HF), the final manifestation of many cardiovascular pathologies, is a devastating disease with poor prognosis, exacerbated by concomitant kidney dysfunction. Cardiorenal syndrome (CRS) is the pathologic crosstalk between the heart and kidney, including increased fibrosis and failure of both organsd. Worsening renal function co-exists with HF in CRS2 and is a strong predictor of mortality in HF patients. Pathologically activated fibroblasts transition to myofibroblasts (MFs) to exacerbate tissue remodeling. Novel POSTNMerCreMer and Tcf21MerCreMer knock-in mice permit targeted, inducible fibroblast modulation in vivo. In HF or kidney injury, chronic stimulation of G-protein coupled receptors (GPCRs) elicits pathologic upregulation of GPCR kinase 2 (GRK2) that is recruited to membrane Gβγ subunits to modulate agonist-occupied GPCRs. Systemic delivery of our novel small molecule Gβγ-GRK2 inhibitor, gallein, attenuates fibrosis, HF and GRK2 expression following transverse aortic constriction (TAC). GRK2 ablation in activated fibroblasts (GRK2fl/fl-POSTNMerCreMer) after cardiac ischemia/reperfusion (I/R) injury was cardioprotective, with no further protection conferred by gallein. TAC or I/R injury resulted in CRS2, including kidney fibrosis and dysfunction, as well as elevation of GRK2 and endothelin (ET) characteristic of renal dysfunction. Gallein attenuated kidney fibrosis, dysfunction, GRK2 expression and ET following TAC or I/R. Gβγ-GRK2 inhibition also attenuated renal dysfunction and fibrosis following acute renal I/R injury, suggesting a direct protective effect of blocking Gβγ-GRK2 signaling in kidney dysfunction. Novel Cre mice ablate GRK2 in either kidney pericytes (FoxD1Cre) or epithelial cells (Six2Cre) and will be used to evaluate the role of Gβγ- GRK2 signaling in kidney fibrosis. Our hypothesis is that Gβγ-GRK2 plays an important role in pathologic fibrotic remodeling in both HF progression and kidney dysfunction and that its inhibition holds therapeutic promise for fibrotic remodeling in HF, kidney injury and CRS2. To address our hypothesis, we propose the following: Aim 1. Determine the therapeutic efficacy and specificity of Gβγ-GRK2 inhibition or ablation in cardiac fibrosis and CRS2. Aim 2. Determine the therapeutic efficacy and specificity of Gβγ-GRK2 inhibition or ablation in renal fibrosis and CRS2. Specific Aim 3: Elucidate the cellular mechanisms of Gβγ-GRK2 inhibition in cardiac and renal fibroblasts and validate Gβγ-GRK2 as a therapeutic target in mouse and human cardiac fibrosis, kidney fibrosis and HF. We believe this proposal, with Gβγ-GRK2 inhibitory compounds validated in various GRK2 null mice in cardiac and renal fibrosis, holds therapeutic promise for HF, CRS2, kidney injury and possibly other fibrotic diseases.

摘要：纤维化是多种组织病理重塑的关键组成部分，没有具体的治疗方法 目标适应不良纤维化。心力衰竭（HF）是许多心血管疾病的最终表现，是一种 预后不良的毁灭性疾病，并因伴随的肾功能障碍而加剧。心肾 综合征（CRS）是心脏和肾脏之间的病理性串扰，包括纤维化增加和 两个器官均衰竭 D．肾功能恶化与 CRS2 中的 HF 共存，并且是 CRS2 的强烈预测因子 心力衰竭患者的死亡率。病理激活的成纤维细胞转变为肌成纤维细胞（MF）以加剧 组织重塑。新型 POSTNMerCreMer 和 Tcf21MerCreMer 敲入小鼠允许靶向诱导成纤维细胞 体内调节。在心力衰竭或肾损伤中，G 蛋白偶联受体 (GPCR) 的慢性刺激会引发 GPCR 激酶 2 (GRK2) 的病理性上调，该激酶被招募至膜 Gβγ 亚基以进行调节 激动剂占据的 GPCR。我们的新型小分子 Gβγ-GRK2 抑制剂 Gallein 的全身给药， 减轻横主动脉缩窄 (TAC) 后的纤维化、HF 和 GRK2 表达。 GRK2 消融 心脏缺血/再灌注（I/R）损伤后活化的成纤维细胞（GRK2fl/fl-POSTNMerCreMer） 具有心脏保护作用，但没食子菜素没有提供进一步的保护作用。 TAC 或 I/R 损伤导致 CRS2，包括 肾脏纤维化和功能障碍，以及肾脏特征性的 GRK2 和内皮素 (ET) 升高 功能障碍。 Gallein 可减轻 TAC 或 I/R 后的肾纤维化、功能障碍、GRK2 表达和 ET。 Gβγ-GRK2 抑制还可减轻急性肾 I/R 损伤后的肾功能障碍和纤维化，表明 阻断 Gβγ-GRK2 信号传导对肾功能障碍的直接保护作用。新型 Cre 小鼠消除 GRK2 在肾周细胞 (FoxD1Cre) 或上皮细胞 (Six2Cre) 中，将用于评估 Gβγ- 的作用 肾纤维化中的 GRK2 信号传导。我们的假设是 Gβγ-GRK2 在病理学中发挥重要作用 心力衰竭进展和肾功能障碍中的纤维化重塑及其抑制作用 心力衰竭、肾损伤和 CRS2 纤维化重塑的治疗前景。为了解决我们的假设， 我们提出以下建议： 目标 1. 确定 Gβγ-GRK2 的治疗功效和特异性 抑制或消融心脏纤维化和 CRS2。目标 2. 确定治疗效果并 Gβγ-GRK2 抑制或消融在肾纤维化和 CRS2 中的特异性。具体目标 3：阐明 心脏和肾成纤维细胞中 Gβγ-GRK2 抑制的细胞机制，并验证 Gβγ-GRK2 小鼠和人类心脏纤维化、肾纤维化和心力衰竭的治疗靶点。我们相信这一点 提案，Gβγ-GRK2 抑制化合物在各种 GRK2 缺失小鼠的心脏和肾脏中得到验证 纤维化，有望治疗心力衰竭、慢性鼻窦炎、肾损伤和其他可能的纤维化疾病。