Contribution of Macropinocytosis in fibroblast activation and systemic sclerosis

巨胞饮作用在成纤维细胞活化和系统性硬化症中的作用

• 批准号: 10353766
• 负责人: Konstantin Tsoyi
• 金额: $ 21.12万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10353766
• 关键词: Actins; Address; Amiloride; Amino Acids; Animal Model; Apoptosis; Attenuated; Autoimmune Diseases; Automobile Driving; Cause of Death; Cell Aging; Cell Survival; Cells; Cessation of life; Clathrin; Complex; Complication; Data; Dermal; Development; Disease; Effector Cell; Endocytosis; Environment; Extracellular Fluid; Extracellular Matrix; Fatty Acids; Fibroblasts; Fibrosis; Gene Expression; Genetic Transcription; Goals; High Prevalence; Imipramine; In Vitro; Interstitial Lung Diseases; Laboratories; Lung; Lung fibrogenesis; Mediating; Molecular; Morbidity - disease rate; Mus; Myofibroblast; Nutrient; Organ; Organelles; Pathogenesis; Pathogenicity; Patients; Pharmaceutical Preparations; Pharmacology; Phenotype; Phosphatidylinositols; Phosphotransferases; Play; Prevalence; Process; Production; Profibrotic signal; Proteins; Publishing; Pulmonary Fibrosis; Research; Resistance; Respiratory Failure; Rheumatism; Role; Scleroderma; Signal Pathway; Skin; Smooth Muscle Actin Staining Method; Systemic Scleroderma; TGFB1 gene; Techniques; Testing; Therapeutic; Therapeutic Intervention; Tuberous Sclerosis; United States; United States Food and Drug Administration; Vacuolar Protein Sorting; Vascular Diseases; Virus; base; cancer cell; cell motility; clinical heterogeneity; effective therapy; extracellular; feasibility testing; fibrogenesis; in vivo; indium-bleomycin; inhibitor; loss of function; member; migration; mortality; polypeptide; programs; response; skin fibrosis; therapeutic target; transcriptome sequencing; uptake

PROJECT SUMMARY/ABSTRACT This R21 proposal describes a two-year research plan that will facilitate research program dedicated to determining the role of macropinocytosis in systemic sclerosis (SSc, scleroderma) and SSc-associated interstitial lung disease (ILD). SSc is an autoimmune disorder, which is manifested by skin fibrosis, vasculopathy and the fibrosis of internal organs. The prevalence of SSc is estimated to range from 50 to 300 per million across the world, with one of the highest prevalence rates observed in the United States at 240 per million. Because of its clinical heterogeneity, SSc is a challenging disease to manage which results in the highest disease mortality among the rheumatologic diseases. ILD is the most common lung complication of SSc and is associated with increased mortality. ILD occurs in up to 80% of patients with SSc, with 25–30% developing a severe progressive form of SSc-ILD leading to eventual respiratory failure and death. Little is known about the molecular mechanisms involved in the pathogenesis of SSc and SSc-ILD. This project will focus on elucidating the key roles of macropinocytosis in skin and lung fibrogenesis, as well as its therapeutic targeting. Macropinocytosis is an actin-dependent but clathrin-independent endocytic process that mediates the nonselective internalization of extracellular contents, such as proteins, cell debris, or viruses. Macropinocytosis has been shown to be involved in cell survival, migration and invasion by providing nutrients (e.g., free amino acids and polypeptides) from extracellular environment. However, its role in scleroderma and organ fibrogenesis is unknown. Our preliminary findings suggest that inhibition of macropinocytosis attenuates dermal myofibroblast differentiation and pulmonary fibrosis in mice. Furthermore, we found that vacuolar protein sorting 34 (Vps34), a sole member of class III phosphoinositide-3-kinase (PI3K), is involved in macropinocytosis and fibroblast activation. Based on published and our preliminary findings, we hypothesize that increased macropinocytosis promotes the development of dermal and lung fibrosis in SSc. Thus, its inhibition exerts anti-fibrotic effects in the animal model of skin fibrosis by reducing profibrotic responses in activated fibroblasts. We also hypothesize that Vps34 is essential for macropinocytosis, which in turn confers to fibroblast activation. We will test our hypotheses by addressing the following Specific Aims: Specific Aim #1: To demonstrate that macropinocytosis inhibition attenuates dermal and lung fibrosis in mice by inhibiting fibroblast to myofibroblast differentiation, ECM production, and migration. Specific Aim #2: To demonstrate that Vps34 is a key protein in macropinosome formation and contributes to profibrotic responses of dermal and lung fibroblasts.

项目摘要/摘要 这份R21提案描述了一项为期两年的研究计划，该计划将促进致力于 确定巨噬细胞吞噬在系统性硬化症(SSC、硬皮病)和SSC相关间质中的作用 肺部疾病(ILD)。SSc是一种自身免疫性疾病，表现为皮肤纤维化、血管病变和 内脏纤维化。据估计，SSc的患病率在每百万人中有50到300人。 美国是世界上患病率最高的国家之一，每百万人中有240人患此病。因为它的 临床异质性，SSc是一种具有挑战性的疾病，它会导致最高的疾病死亡率 在风湿病中。ILD是SSc最常见的肺部并发症，与 死亡率上升。高达80%的SSc患者会发生ILD，其中25%-30%的患者进展严重 导致最终呼吸衰竭和死亡的SSc-ILD形式。人们对这种分子知之甚少 SSC和SSC-ILD的发病机制。这个项目将集中于阐明关键 巨噬细胞增多在皮肤和肺纤维化形成中的作用及其治疗靶点。巨噬细胞增多症 一种依赖肌动蛋白但不依赖于细胞骨架蛋白的内吞过程，其介导的非选择性内化 胞外内容物，如蛋白质、细胞碎片或病毒。巨噬细胞增多症已被证明与此有关 在细胞存活、迁移和入侵中通过提供营养物质(例如，游离氨基酸和多肽) 细胞外环境。然而，它在硬皮病和器官纤维化中的作用尚不清楚。我们的预赛 研究结果表明，抑制巨噬细胞吞噬作用可减弱真皮肌成纤维细胞的分化和 小鼠肺纤维化模型。此外，我们还发现了空泡蛋白分选34(Vps34)，它是空泡蛋白的唯一成员 III型磷脂酰肌醇-3-激酶(PI3K)参与巨噬细胞吞噬和成纤维细胞的激活。基于 已发表的和我们的初步发现，我们假设增加巨噬细胞吞噬促进 SSc真皮和肺纤维化的发生发展。因此，它的抑制作用发挥了抗肝纤维化的作用。 通过减少激活的成纤维细胞的促纤维化反应建立皮肤纤维化的动物模型。我们也 假设Vps34是巨噬细胞吞噬所必需的，而巨噬细胞吞噬又促进成纤维细胞的激活。 我们将通过解决以下具体目标来测试我们的假设：具体目标1：证明 巨噬细胞吞噬抑制通过抑制成纤维细胞对肌成纤维细胞的作用减轻小鼠皮肤和肺纤维化 分化、ECM生产和迁移。具体目标2：证明Vps34是一种关键蛋白 巨细胞体的形成，并有助于真皮和肺成纤维细胞的促纤维化反应。