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）是一种可溶的，二聚体糖蛋白，其六聚体结构由三对二硫化二硫键链的多肽链（FG1，FG2和FG3）组成。在全基因组表达分析中，我们发现FG2是在20分钟双侧缺血/再灌注（I/R）损伤20分钟后24小时在大鼠肾脏中22,523个基因中上调的第二高基因。在肾脏，大鼠和人类肾脏损伤后，肾脏中的mRNA水平和从肾脏中的NOVO蛋白合成以及FG的尿液排泄显着增加。在正常条件下，FG由肾脏中的上皮和内皮细胞表达，受伤后FG1的表达显着增加了肾小管上皮细胞的基底外侧膜的表达，FG3的定位从基底外侧到根尖膜的定位变化，而FG2的表达在肾室内占主导地位。此外，FG蛋白（0.5、1或2 mg/ml）刺激肾上皮细胞的增殖（HEK293和LLCPK1）以剂量依赖性方式刺激200％。 FG被认为是止血，炎症和伤口愈合的重要调节剂，但是，关于FG信号在肾上皮细胞中功能意义的知识非常有限，甚至了解FG1，FG2和FG3的作用机理的知识较少，基于其分子的确认，其功能很独特。鉴于FG通过广泛的细胞受体进行信号转导的潜力；它在体内平衡期间在肾脏中的表达及其在受伤后表达的显着表达，我们假设FG在体内稳态期间保持细胞分化，而肾损伤则上调FG触发了组织修复。在第一个目标中，我们将进行翻译研究，以表征急性和慢性肾损伤后FG及其链FG1，FG2和FG3的细胞表达和尿排泄。在第二个目标中，我们建议使用体外遗传操纵方法分析FG在与肾小管上皮细胞的去分化，增殖和细胞骨架重排相关的过程中的机械作用。第三个目标将评估FG信号在使用FG无效小鼠调节肾脏组织修复中的关键作用，还将测试FG（B215-42和3377-395）多肽在肾脏损伤动物模型中的疗效。了解肾脏损伤后肾脏再生的FG信号转导可能为早期诊断，预防和治疗性干预提供机会。 公共卫生相关性：肾脏疾病是一个主要的公共卫生问题，由于疾病的患病率显着提高和高死亡率，因此受到了全球关注。拟议的研究旨在发现肾脏中的新途径，该途径可能有助于早期发现以及制定治疗策略来解决肾脏损伤。