Targeting Cell-specific Functions of the Rho Kinase Pathway in Pulmonary Fibrosis

肺纤维化中 Rho 激酶通路的靶向细胞特异性功能

• 批准号: 9277557
• 负责人: JASON R. McCARTHY
• 金额: $ 67.32万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2020-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9277557
• 关键词: Actomyosin; Adverse effects; Affect; Affinity; Alpha Cell; Alveolar; Apoptosis; Architecture; Attenuated; Automobile Driving; Bleomycin; Cell physiology; Cells; Cessation of life; Characteristics; Collagen; Cytoskeletal Modeling; Cytoskeleton; Development; Disease; Dose; Drug Delivery Systems; Dyspnea; Encapsulated; Environment; Epithelial; Epithelial Cells; Extracellular Matrix; Fibroblasts; Fibrosis; Gene Expression; Genes; Genetic Transcription; Guanosine Triphosphate Phosphohydrolases; Hamman-Rich syndrome; Impairment; In Vitro; Label; Ligands; Longitudinal Studies; Lung; Lung diseases; Mediating; Mediator of activation protein; Microfilaments; Modeling; Morbidity - disease rate; Mus; Myofibroblast; Nature; Nodal; Nuclear Translocation; Pathologic; Pathway interactions; Peptides; Persons; Pharmaceutical Preparations; Physiological; Polymers; Positioning Attribute; Process; Production; Protein Isoforms; Pulmonary Fibrosis; ROCK1 gene; Resistance; Respiratory physiology; Rho-associated kinase; Role; Serum Response Factor; Signal Pathway; Signal Transduction; Testing; Therapeutic; Wound Healing; base; cell injury; cell type; design; drug development; efficacy study; endoplasmic reticulum stress; experimental study; fluorescence imaging; imaging agent; in vivo; inhibitor/antagonist; lung injury; mortality; myocardin; nanomaterials; nanoparticle; non-invasive monitor; novel; novel strategies; novel therapeutic intervention; particle; receptor; repaired; response; senescence; tissue repair; transcription factor; uptake

Project Summary Lung fibrosis is thought to be driven by aberrant wound healing responses to repetitive alveolar epithelial cell (AEC) injury, culminating in excessive fibroblast accumulation and extracellular matrix production. The aberrant wound healing responses that drive fibrosis overlap substantially with physiologic responses that mediate tissue repair, however, creating a major challenge in drug development: anti-fibrotic therapies need to inhibit pathologic wound healing responses while preserving physiologic responses as much as possible. We hypothesize that cell-specific drug delivery will be able to help to meet this challenge. Here we will identify specific cell types in which deletion of a central pro-fibrotic pathway in those cells alone is adequate to reduce fibrosis, and then develop the ability to deliver inhibitors of that pathway exclusively to that specific cell type. RhoA‒Rho kinase signaling is emerging as nodal point in pulmonary fibrosis, through which many upstream signals induce pro-fibrotic downstream responses. Activation of the Rho kinase isoforms ROCK 1 and ROCK2 regulates the cytoskeleton through actin filament assembly, driving many pro-fibrotic wound healing responses, including gene expression: actin filament assembly promotes nuclear translocation of the myocardin-related transcription factors (MRTFs), which activate serum response factor (SRF)-induced transcription of pro-fibrotic mediators. Based on its position at the center of multiple pro-fibrotic pathways, inhibition of RhoA‒ROCK signaling may be a particularly potent strategy for pulmonary fibrosis. The pleitropic effects of this pathway, however, have raised concerns about on-target adverse effects of its inhibition. We aim to develop a novel strategy to effectively but safely inhibit RhoA-ROCK signaling in pulmonary fibrosis, by developing the capacity to deliver inhibitors of this pathway in a cell-specific manner. We will first identify cell types in which RhoA‒ROCK signaling is critical to fibrosis, focusing on the AEC and the fibroblast. We will define the cell-specific roles of RhoA‒ROCK signaling in pulmonary fibrosis using mice in which either ROCK1 or ROCK 2 is specifically deleted in AECs or fibroblasts. We then will develop nanomaterial-based drug delivery vehicles to target inhibitors of RhoA‒ROCK signaling specifically to AECs or fibroblasts, and test their ability to treat fibrosis. We will encapsulate ROCK, MRTF or SRF inhibitors in polymeric nanoparticles that will be targeted by peptide affinity ligands to AECs or fibroblasts. We will study the efficacy of these nanoagents in two fibrosis models: a standard bleomycin model and a model in which low-dose bleomycin produces fibrosis in the context of exaggerated AEC endoplasmic reticulum (ER) stress, capturing the “gene- by-environment” nature of pulmonary fibrosis. In addition to invasive assessments of fibrosis, we will assess fibrosis non-invasively using a near-infrared fluorescent imaging agent specific for collagen, allowing for longitudinal studies of nanoagent efficacy. If successful, our experiments will provide evidence for the potential of novel cell-specific targeting strategies to enhance our ability to treat pulmonary fibrosis.

项目摘要 肺纤维化被认为是由对重复的肺泡上皮细胞的异常伤口愈合反应所致 细胞(AEC)损伤，最终导致成纤维细胞过度堆积和细胞外基质产生。这个 导致纤维化的异常伤口愈合反应与生理反应有很大重叠 然而，中介组织修复在药物开发中造成了一个重大挑战：抗纤维化疗法需要 抑制病理性伤口愈合反应，同时尽可能保留生理反应。我们 假设细胞特异性药物传递将能够帮助应对这一挑战。在这里，我们将确定 一种特定的细胞类型，在这些细胞中，仅删除中心促纤维化途径就足以减少 纤维化，然后发展出将该途径的抑制剂专门输送到特定细胞类型的能力。 RhoA-Rho激酶信号正在成为肺纤维化的结点，通过许多 上游信号诱导促肝纤维化的下游反应。Rho激酶异构体ROCK 1的激活 而ROCK2通过肌动蛋白细丝组装来调节细胞骨架，驱动许多促纤维化的伤口 修复反应，包括基因表达：肌动蛋白细丝组装促进细胞核移位 肌钙蛋白相关转录因子(MRTF)激活血清反应因子(SRF)诱导的 促纤维化介质的转录。根据它在多条促纤维化途径中心的位置， 抑制RhoA-ROCK信号可能是治疗肺纤维化的一种特别有效的策略。多面性 然而，这一途径的影响已经引起了人们对其抑制的靶向不利影响的担忧。 我们的目标是开发一种新的策略，有效而安全地抑制肺组织中的RhoA-ROCK信号 纤维化，通过发展以细胞特异性方式递送这一途径的抑制物的能力。我们将首先 确定RhoA-ROCK信号在纤维化中起关键作用的细胞类型，重点关注血管内皮细胞和成纤维细胞。 我们将使用小鼠来确定RhoA-ROCK信号在肺纤维化中的细胞特异性作用 ROCK1或ROCK 2在血管内皮细胞或成纤维细胞中被特异性缺失。然后我们将开发基于纳米材料的 靶向RhoA-ROCK信号转导靶向血管内皮细胞或成纤维细胞的药物载体，并测试 他们治疗纤维化的能力。我们将在聚合物纳米颗粒中包裹ROCK、MRTF或SRF抑制剂 这将通过与血管内皮细胞或成纤维细胞的多肽亲和配体来靶向。我们将研究这些药物的功效。 纳米制剂在两种纤维化模型中的作用：标准博莱霉素模型和小剂量博莱霉素模型 在夸大的AEC内质网(ER)应激背景下产生纤维化，捕捉到“基因- 肺纤维化的“环境副”性质。除了对纤维化的侵入性评估外，我们还将评估 使用一种专用于胶原的近红外荧光成像剂进行非侵入性纤维化，允许 纳米药剂功效的纵向研究。如果成功，我们的实验将为这种潜力提供证据 新的细胞特异性靶向策略，以提高我们治疗肺纤维化的能力。