Interaction of fibroblasts with cell corpses increases collagen synthesis during lung repair

成纤维细胞与细胞尸体的相互作用增加了肺修复过程中的胶原蛋白合成

基本信息

批准号：
10736792
负责人：
Alexandra Leigh McCubbrey
金额：
$ 61.93万
依托单位：
NATIONAL JEWISH HEALTH
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-07-01 至 2028-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10736792
关键词：
Address Alveolar Apoptotic Basement membrane Binding Biological Process Bleomycin Blood capillaries Cell Death Cell Proliferation Cells Coculture Techniques Collagen Cues Data Deposition Development Enzymes Extracellular Matrix Fibroblasts Gene Deletion Health Human In Vitro Inflammation Injury Isotopes Lipids Liposomes Lung Macrophage Maintenance Molecular Conformation Mus Ornithine Decarboxylase Phagocytes Phosphatidylserines Polyamines Production Proliferating Protein Biosynthesis Proteins Proteomics Pulmonary Inflammation Research Ribosomes Role Signal Transduction Small Interfering RNA Spermidine Tamoxifen Testing Translations Work deoxyhypusine synthase eIF-5A healing hypusine in vivo inhibitor lung health lung injury lung repair metabolomics novel novel strategies novel therapeutics phosphatidylserine receptor polyproline prevent receptor reconstitution repair function repaired response restoration scaffold seal tissue injury tissue repair transcriptome sequencing wound closure

项目摘要

PROJECT SUMMARY Repair after injury is a fundamental biologic process that is critical for maintaining lung health. Fibroblasts must perform key pro-repair functions after injury including proliferation and synthesis of new extracellular matrix, particularly collagens, that scaffold wound closure. Dead cells (collectively termed cell corpses) are produced during lung injury and inflammation and have been shown to promote the transition from inflammation to repair. Prior research has focused on understanding macrophage interactions with apoptotic corpses. However, non- professional phagocytes including fibroblasts can also interact with cell corpses and the consequence of these interactions in the lung has not been studied. This proposal seeks to address unknowns regarding fibroblast- corpse interactions and their role in healthy lung repair. We have found that recognition of cell corpses by fibroblasts causes fibroblasts to increase collagen protein synthesis. Our preliminary data support a mechanism where the phosphatidylserine receptor Axl binds cells corpses, activates polyamine metabolite synthesis, increasing intracellular spermidine levels, which fuel hypusination. Hypusination occurs on a single protein: the ribosomal subunit eiF5a. When hypusinated, eiF5a is able to stabilize translation of poly-proline-repeat proteins including collagen. Hypusination is also important for cell proliferation. Blocking polyamine synthesis prevented hypusination of eiF5a in response to corpse recognition. Blocking Axl or hypusine-eiF5a prevented the increase in collagen in response to corpse recognition. We also show that, in vivo, hypusine-eiF5a is increased in fibroblasts after lung injury and that collagen deposition and alveolar-capillary repair are reduced when hypusination is blocked with the inhibitor GC7 or through targeted deletion of the hypusination enzyme deoxyhypusine synthase in fibroblasts. This led us to hypothesize that interaction of fibroblasts with cell corpses is a central cue that activates fibroblast proliferation and collagen synthesis following lung injury, facilitating repair. We will use three aims to test if 1) corpse recognition via Axl triggers a translationally-regulated increase in collagen protein, 2) corpse recognition drives polyamine synthesis that increases spermidine that increases hypusine-eiF5a and stabilizes collagen translation, and 3) to fully activate pro-repair programming fibroblasts require the ability to sense corpses via Axl, synthesize polyamines via ornithine decarboxylase, and hypusinate eiF5a via deoxyhypusine synthase in order to proliferate and synthesize new extracellular matrix after lung injury.

项目概要损伤后修复是一个基本的生物过程，对于维持肺部健康至关重要。成纤维细胞必须损伤后执行关键的促修复功能，包括新细胞外基质的增殖和合成，特别是胶原蛋白，它是伤口闭合的支架。产生死亡细胞（统称为细胞尸体）在肺损伤和炎症期间，并已被证明可以促进从炎症到修复的转变。先前的研究重点是了解巨噬细胞与凋亡尸体的相互作用。然而，非包括成纤维细胞在内的专业吞噬细胞也可以与细胞尸体相互作用，以及这些的后果尚未研究肺部的相互作用。该提案旨在解决有关成纤维细胞的未知问题尸体相互作用及其在健康肺部修复中的作用。我们发现细胞尸体的识别成纤维细胞导致成纤维细胞增加胶原蛋白的合成。我们的初步数据支持一种机制其中磷脂酰丝氨酸受体 Axl 结合细胞尸体，激活多胺代谢物合成，增加细胞内亚精胺水平，从而促进催眠。兴奋作用发生在单一蛋白质上：核糖体亚基eiF5a。当 hypus 化时，eiF5a 能够稳定聚脯氨酸重复蛋白的翻译包括胶原蛋白。静息作用对于细胞增殖也很重要。阻止多胺合成 eiF5a 因尸体识别而发生催眠。阻断 Axl 或 hypusine-eiF5a 可防止增加胶原蛋白对尸体识别做出反应。我们还表明，在体内，hypusine-eiF5a 在肺损伤后的成纤维细胞以及胶原蛋白沉积和肺泡毛细血管修复减少催眠作用可通过抑制剂 GC7 或通过靶向删除催眠酶来阻断成纤维细胞中的脱氧马尿苷合成酶。这使我们推测成纤维细胞与细胞尸体的相互作用是肺损伤后激活成纤维细胞增殖和胶原蛋白合成的中心线索，促进维修。我们将使用三个目标来测试 1) 通过 Axl 进行的尸体识别是否会触发翻译调节的增加在胶原蛋白中，2) 尸体识别驱动多胺合成，从而增加亚精胺，从而增加 hypusine-eiF5a 并稳定胶原蛋白翻译，3) 完全激活促修复编程成纤维细胞需要通过 Axl 感知尸体、通过鸟氨酸脱羧酶合成多胺和海普辛的能力 eiF5a 通过脱氧马尿苷合成酶在肺损伤后增殖并合成新的细胞外基质。