IGFBP-5 and Hsp70 in Extracellular Matrix Homeostasis and Fibrosis

IGFBP-5 和 Hsp70 在细胞外基质稳态和纤维化中的作用

• 批准号: 8279298
• 负责人: Kristen L Veraldi
• 金额: $ 12.49万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-15 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8279298
• 关键词: Affect; Affinity; Apoptosis; Binding; Biochemical Genetics; Biology; Cell surface; Cells; Cicatrix; Collagen; Connective Tissue Diseases; Deposition; Development; Development Plans; Disease; Down-Regulation; Equilibrium; Extracellular Matrix; Extracellular Matrix Proteins; Family; Fibroblasts; Fibronectins; Fibrosis; Foundations; Goals; Hamman-Rich syndrome; Heat shock proteins; Heat-Shock Proteins 70; Heat-Shock Response; Homeostasis; Human; In Vitro; Instruction; Insulin-Like Growth Factor Binding Protein 5; Insulin-Like Growth Factor I; Insulin-Like Growth-Factor-Binding Proteins; Interstitial Lung Diseases; Investigation; Laboratories; Lead; Lung; Lung diseases; MAP Kinase Gene; Maintenance; Mediating; Mediator of activation protein; Medical; Mentors; Molecular; Morbidity - disease rate; Mus; Pathway interactions; Patients; Positioning Attribute; Principal Investigator; Production; Proteins; Proteolysis; Pulmonary Fibrosis; Regulation; Research Personnel; Role; Scleroderma; Signal Pathway; Signal Transduction; Solid; Somatomedins; Structural Protein; Structure of parenchyma of lung; Systemic Scleroderma; Tissues; Work; abstracting; career development; cell growth; design; effective therapy; fibrogenesis; heat shock transcription factor; improved; in vivo; insight; mortality; mouse model; novel; novel diagnostics; novel therapeutics; response; transcription factor

DESCRIPTION (provided by applicant): Interstitial lung disease (ILD) comprises a group of more than 130 disorders characterized by scarring, or fibrosis, of the lungs. The causes of some of the ILDs are known, including those associated with connective tissue diseases such as systemic sclerosis (SSc, or scleroderma). Despite intense study, however, the basic mechanisms responsible for the initiation and perpetuation of fibrosis remain elusive. This proposal outlines a detailed 5-year scientific and career development plan designed to facilitate the applicant's successful transition to the role of independent investigator and provide a solid foundation for her to become a world-class researcher in matrix biology and fibrotic lung disease. Work performed in the mentor's laboratory has demonstrated increased expression of insulin-like growth factor binding protein 5 (IGFBP-5) in scleroderma fibroblasts and fibrotic lung tissue from patients with idiopathic pulmonary fibrosis. Furthermore, over-expression of IGFBP-5 in vitro and in vivo results in aberrant extracellular matrix (ECM) production, a hallmark of fibrotic disease. IGFBP-5 induces expression of the major extracellular matrix proteins fibronectin and collagen I. Additionally, there is reduced expression of the Hsp70 heat shock protein both in vivo in lung tissue and primary fibroblasts from patients with SSc-associated pulmonary fibrosis and in vitro in response to lGFBP-5 over-expression. We hypothesize that IGFBP-5 increases production of matrix structural proteins through Hsp70-dependent pathways, thereby disrupting ECM homeostasis and resulting in fibrosis. The specific aims of this proposal are to (1) identify the mechanism of lGFBP-5 mediated ECM imbalance, (2) characterize the regulation of Hsp70 by IGFBP-5, and (3) characterize the role of Hsp70 and the heat shock transcription factors in the regulation of ECM deposition. Biochemical and genetic in vitro studies in primary mouse and human lung fibroblasts will elucidate signaling pathways and transcription factors involved in lGFBP-5's regulation of Hsp70 and the ECM, as well as in regulation of ECM production by heat shock proteins and transcription factors. Complementary in vivo work will be conducted in a mouse model of IGFBP-5 over-expression in the lung. In total, these studies will provide mechanistic insight into the IGFBP-5 pro-fibrotic cascade and the role of the heat shock response in ECM deposition, leading to an enhanced understanding of the derangements in extracellular matrix homeostasis that lead to fibrosis. RELEVANCE (See instructions): The interstitial lung diseases (ILDs) result in significant morbidity and mortality, and there are no effective medical therapies to reverse fibrosis. The proposed investigations will not only serve to define how lGFBP-5 and Hsp70 affect extracellular matrix balance, but will also provide better insight into the mechanisms of fibroproliferative diseases in the lung and serve as a foundation for the development of novel diagnostic and therapeutic strategies for the ILDs. (End of Abstract)

描述（由申请人提供）：间质性肺病（ILD）包括一组超过130种以肺瘢痕形成或纤维化为特征的疾病。一些ILD的病因是已知的，包括与结缔组织疾病如系统性硬化症（SSc或硬皮病）相关的那些。然而，尽管进行了大量的研究，但导致纤维化发生和持续的基本机制仍然难以捉摸。该提案概述了一个详细的5年科学和职业发展计划，旨在促进申请人成功过渡到独立研究者的角色，并为她成为基质生物学和纤维化肺病的世界级研究人员提供坚实的基础。在导师的实验室中进行的工作已经证明了胰岛素样生长因子结合蛋白5（IGFBP-5）在硬皮病成纤维细胞和特发性肺纤维化患者的纤维化肺组织中的表达增加。此外，IGFBP-5在体外和体内的过表达导致异常的细胞外基质（ECM）产生，这是纤维化疾病的标志。IGFBP-5诱导主要细胞外基质蛋白纤连蛋白和胶原I的表达。此外，在体内肺组织和来自患有Ssc相关肺纤维化的患者的原代成纤维细胞中以及在体外响应于IGFBP-5过表达，存在Hsp 70热休克蛋白的表达降低。我们假设IGFBP-5通过Hsp 70依赖性途径增加基质结构蛋白的产生，从而破坏ECM稳态并导致纤维化。本研究的具体目的是（1）确定IGFBP-5介导的ECM失衡的机制，（2）表征IGFBP-5对Hsp 70的调节，和（3）表征Hsp 70和热休克转录因子在ECM沉积调节中的作用。在原代小鼠和人肺成纤维细胞中的生物化学和遗传体外研究将阐明参与lGFBP-5对Hsp 70和ECM的调节以及参与热休克蛋白和转录因子对ECM产生的调节的信号传导途径和转录因子。将在肺中IGFBP-5过表达的小鼠模型中进行补充体内工作。总之，这些研究将提供对IGFBP-5促纤维化级联反应和热休克反应在ECM沉积中的作用的机制性见解，从而增强对导致纤维化的细胞外基质稳态紊乱的理解。相关性（参见说明）：间质性肺疾病（ILD）导致显著的发病率和死亡率，并且没有有效的药物治疗来逆转纤维化。所提出的研究将不仅用于确定lGFBP-5和Hsp 70如何影响细胞外基质平衡，而且还将提供对肺中纤维增生性疾病的机制的更好的了解，并作为开发ILD的新诊断和治疗策略的基础。 (End摘要）