FIBRINOGEN SIGNALING IN KIDNEY TISSUE REPAIR

肾脏组织修复中的纤维蛋白原信号传导

• 批准号: 8181614
• 负责人: Vishal S. Vaidya
• 金额: $ 48.32万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-07 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8181614
• 关键词: Acute; Address; Adhesions; Animal Model; Animals; Attention; Bilateral; Binding; Biological Markers; Biopsy; Cadmium; Calcium; Capillary Endothelial Cell; Cell Communication; Chronic; Chronic Kidney Failure; Cisplatin; DNA Sequence Rearrangement; Disease; Disulfides; Dose; Early Diagnosis; Endothelial Cells; Epidermal Growth Factor Receptor; Epithelial; Epithelial Cells; Excretory function; Extracellular Matrix; Fibrinogen; Fibrosis; Functional disorder; Genes; Glycoproteins; Hemostatic function; Homeostasis; Hospitals; Hour; Human; In Vitro; Inflammation; Injury; Inpatients; Integrins; Ischemia; Kidney; Kidney Diseases; Knock-out; Knockout Mice; Knowledge; Leukocytes; Link; Messenger RNA; Modeling; Molecular; Mus; Natural regeneration; Outpatients; Pathway interactions; Patient Schedules; Pattern; Peptides; Pericytes; Phosphorylation; Prevalence; Prevention; Process; Protein Biosynthesis; Proteins; Public Health; Rattus; Reperfusion Injury; Reperfusion Therapy; Role; Signal Transduction; Structure; Therapeutic; Therapeutic Intervention; Tissues; Treatment Efficacy; Tubular formation; Urine; Woman; Wound Healing; Xenobiotics; apical membrane; base; basolateral membrane; cell dedifferentiation; efficacy testing; genetic manipulation; genome-wide; in vivo Model; injury and repair; insight; kidney epithelial cell; migration; mortality; novel; polypeptide; receptor; repaired; therapeutic target; transcription factor; translational study; urinary; wound

DESCRIPTION (provided by applicant): Fibrinogen (Fg) is a soluble, dimeric glycoprotein with a hexameric structure composed of three distinct pairs of disulfide-linked polypeptide chains (Fg1, Fg2 and Fg3). In genome-wide expression analysis we found Fg2 to be the second highest gene upregulated amongst 22,523 genes in rat kidney at 24 hours following 20 minutes of bilateral ischemia/reperfusion (I/R) injury. The mRNA levels and de novo protein synthesis in the kidney as well as urinary excretion of Fg is significantly increased following kidney injury in mice, rats and humans. Under normal conditions, Fg is expressed by epithelial and endothelial cells in the kidney and following injury the expression of Fg1 significantly increases on basolateral membrane of the tubular epithelial cells, localization of Fg3 changes from basolateral to apical membrane whereas over expression Fg2 is predominantly in the renal interstitium. Furthermore, Fg protein (0.5, 1 or 2 mg/ml) stimulates proliferation of kidney epithelial cells (HEK293 and LLCPK1) by 200 % in a dose dependent manner. Fg has been recognized as an important regulator of hemostasis, inflammation and wound healing however, there is very limited knowledge about the functional significance of Fg signaling in kidney epithelial cells and even less is known about the mechanisms of action of Fg1, Fg2 and Fg3 that function distinctively based on their molecular confirmations. Given the potential of Fg for signal transduction via a wide range of cellular receptors; its expression in kidney during homeostasis and its significant over expression after injury, we hypothesize that Fg maintains cellular differentiation during homeostasis, whereas kidney injury upregulates Fg triggering tissue repair. In the first aim we will conduct translational studies to characterize the cellular expression and urinary excretion of Fg and its chains Fg1, Fg2 and Fg3 following acute and chronic kidney injury. In the second aim we propose to analyze the mechanistic role of Fg in the processes associated with dedifferentiation, proliferation and cytoskeletal rearrangements of kidney tubular epithelial cells using in vitro genetic manipulation approaches. The third aim will evaluate the critical role of Fg signaling in modulating kidney tissue repair using Fg null mice and will also test the efficacy of polypeptides of Fg (B215-42 and 3377-395) in animal models of kidney injury. Understanding Fg signal transduction in kidney regeneration following kidney damage may provide opportunities for early diagnosis, prevention, and therapeutic interventions. PUBLIC HEALTH RELEVANCE: Kidney disease is a major public health concern receiving increased global attention owing to the significantly increased prevalence of the disease and high mortality rates. The proposed studies aim at uncovering a novel pathway in the kidney that may aid in early detection as well as developing therapeutic strategies to resolve kidney damage.

描述（由申请人提供）：纤维蛋白原（Fg）是一种可溶性二聚体糖蛋白，具有由三对不同的二硫键连接的多肽链（Fg1、Fg2 和 Fg3）组成的六聚体结构。在全基因组表达分析中，我们发现在双侧缺血/再灌注 (I/R) 损伤 20 分钟后 24 小时，Fg2 是大鼠肾脏 22,523 个基因中上调第二高的基因。小鼠、大鼠和人类肾损伤后，肾脏中的 mRNA 水平和从头蛋白质合成以及 Fg 的尿排泄显着增加。正常情况下，Fg由肾脏上皮细胞和内皮细胞表达，损伤后肾小管上皮细胞基底外侧膜上Fg1的表达显着增加，Fg3的定位从基底外侧膜转变为顶膜，而过度表达的Fg2主要在肾小管上皮细胞的基底外侧膜上。肾间质。此外，Fg 蛋白（0.5、1 或 2 mg/ml）以剂量依赖性方式刺激肾上皮细胞（HEK293 和 LLCPK1）增殖 200%。 Fg 已被认为是止血、炎症和伤口愈合的重要调节因子，然而，人们对 Fg 信号在肾上皮细胞中的功能意义的了解非常有限，对 Fg1、Fg2 和 Fg3 的作用机制知之甚少。基于其分子确认而具有独特的功能。鉴于 Fg 通过多种细胞受体进行信号转导的潜力；由于 Fg 在稳态过程中在肾脏中的表达及其在损伤后显着过度表达，我们假设 Fg 在稳态过程中维持细胞分化，而肾损伤则上调 Fg 触发组织修复。第一个目标是进行转化研究，以表征急性和慢性肾损伤后 Fg 及其链 Fg1、Fg2 和 Fg3 的细胞表达和尿液排泄。在第二个目标中，我们建议使用体外遗传操作方法分析 Fg 在肾小管上皮细胞去分化、增殖和细胞骨架重排相关过程中的机制作用。第三个目标将使用 Fg 缺失小鼠评估 Fg 信号传导在调节肾组织修复中的关键作用，并将测试 Fg 多肽（B215-42 和 3377-395）在肾损伤动物模型中的功效。了解肾损伤后肾脏再生中的 Fg 信号转导可能为早期诊断、预防和治疗干预提供机会。 公共卫生相关性：肾脏疾病是一个主要的公共卫生问题，由于该病的患病率显着增加且死亡率较高，因此受到全球越来越多的关注。拟议的研究旨在揭示肾脏中的一种新途径，该途径可能有助于早期检测以及制定解决肾脏损伤的治疗策略。