Peri-arteriolar Myofibroblast Differentiation in the Pathobiology of IPAH

IPAH 病理学中小动脉周围肌成纤维细胞的分化

• 批准号: 8211724
• 负责人: ARTHUR ROGER STRAUCH
• 金额: $ 7.63万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-23 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8211724
• 关键词: Actins; Affect; Back; Biochemical; Blood Vessels; Blood flow; Boxing; Cell Nucleus; Cellular biology; Cicatrix; Coagulation Process; Collagen Type I; Complex; Consensus; DNA; DNA-Binding Proteins; DNA-Protein Interaction; Diagnosis; Disease; Disease Progression; Enzyme-Linked Immunosorbent Assay; Epigenetic Process; Epithelial; Epithelial Cells; Etiology; Fibroblasts; Fibrosis; Fostering; Functional disorder; Future; Gene Activation; Gene Expression; Genes; Heart failure; Individual; Infarction; Infection; Knowledge; Lead; Lung; Lung Transplantation; MAP2K1 gene; Mediating; Mesenchymal; Metabolic; Methods; Molecular; Muscle; Myofibroblast; Obstruction; Organ Transplantation; Output; Patients; Perfusion; Phase; Phosphotransferases; Process; Protein Biochemistry; Proteins; Pulmonary Hypertension; Pulmonary artery structure; Research; Serum Response Factor; Side; Signal Transduction; Site; Smad Proteins; Smad protein; Smooth Muscle; Smooth Muscle Actin Staining Method; Solid; Specimen; Staging; Stroke; Sudden Death; Syndrome; Testing; Tissues; Trans-Activators; Transcription Coactivator; Transcription Repressor/Corepressor; Transcriptional Activation; Trauma; Tunica Media; Vascular Diseases; Vascular remodeling; Wound Healing; abstracting; arm; arterial remodeling; arteriole; base; blood pump; cardiopulmonary system; design; feeding; heart function; immunocytochemistry; improved; lung injury; new therapeutic target; novel; promoter; protein complex; pulmonary arterial hypertension; response; tool; treatment strategy

DESCRIPTION (provided by applicant): Idiopathic and familial syndromes of pulmonary arterial hypertension (IPAH/FPAH) typically are associated with muscularization and obstruction of pulmonary arterial microperfusion circuits in the lung. We propose that the pathobiology of PAH represents a dysfunctional, peri-vascular wound healing response based on a functional deficit in the ability of the recently discovered Pur ? DNA-binding protein to repress TGF?1 signaling in the lung. Excessive transcriptional activation of wound-healing genes due to unchecked collaborative interaction between serum response factor (SRF) and TGF?1-regulated Smad proteins 2 and 3 results in accelerated peri-arteriolar myofibroblast (MFB) differentiation and adventitial fibrosis with loss of pulmonary arterial compliance and eventual right heart failure. Smads 2 and 3 normally dissociate gene-inhibitory SRF-Pur ? protein complexes to allow activation of the smooth muscle ?-actin (SM?A) and type I collagen ?2-subunit promoters as a first step in the MFB differentiation process. We will test the hypothesis that the SRF-Pur? inhibitory complex is unstable in PAH-derived MFBs due to over-active PI3K/Akt feed-forward signaling kinases and/or impaired feed-back inhibition mediated by sub-optimal MEK1/Erk1,2/Egr-1 signaling. In Aim 1, we propose to characterize the sub-cellular compartmentalization of transcriptional activators and repressors implicated in peri-arteriolar myofibroblast differentiation and remodeling in IPAH/FPAH syndromes using an immunocytochemistry approach. For Aim 2, we will define the biochemical dysfunction that causes excess peri-arteriolar myofibroblast differentiation in IPAH/FPAH syndromes using epigenetic/metabolic approaches that target SRF-Pur ? physical interplay in pulmonary artery adventitial fibroblasts isolated from normal or disease-affected donors. We have developed solid-phase ELISA tools to quantitatively evaluate protein:protein and protein:DNA interactions that uniquely regulate the process of adventitial MFB differentiation. The assembly of a specialized transcriptional regulatory complex capable of triggering prototypical gene responses in MFBs represents a convergence point for complex vascular-disease signaling consisting of multiple compensatory and patient-specific layers of control. We expect that knowledge gained could further basic understanding of rate-limiting interactions that foster loss of arterial compliance typically associated with the most devastating IPAH/FPAH disease syndromes. Future detailed analysis of the protein biochemistry of activator-repressor dynamic interplay could reveal novel targets for therapeutic management of pulmonary arterial disease and right heart failure that may ultimately improve patient long-term survival. PUBLIC HEALTH RELEVANCE: Gene activation in the blood vessel wall is controlled by protein:protein and protein:DNA complexes that are necessary for rapid wound healing and tissue repair after infection or physical trauma. When these processes become inoperative or dysfunctional in the cardiopulmonary system, excess scar tissue can accumulate and stiffen very small blood vessels that eventually slows normal blood flow leading to clot formation, stroke, tissue infarction (degradation), and sudden death. Protein complexes that control wound healing in the lung may be faulty in patients with pulmonary hypertension which if untreated will eventually damage the right side of the heart that functions as the blood pump to the lung. The proposed research will examine the protein constituents of these regulatory complexes and determine if they are different in normal individuals compared to patients diagnosed with end-stage pulmonary hypertension. The proposed research may lead to the design of new treatment strategies for this devastating lung vascular disease that has no cure and only treatable by performing lung transplantation surgery. (End of Abstract)

描述（由申请人提供）：肺动脉高压（IPAH/FPAH）的特发性和家族性综合征通常与肺内肺动脉微灌注回路的肌化和阻塞相关。我们建议，PAH的病理生物学代表了一个功能失调，血管周围伤口愈合反应的基础上，最近发现的Pur？DNA结合蛋白抑制TGF？1、肺内信号由于血清反应因子（SRF）和TGF？1-受调节的Smad蛋白2和3导致加速的动脉周围肌成纤维细胞（MFB）分化和外膜纤维化，伴随肺动脉顺应性丧失和最终的右心衰竭。Smads 2和3通常解离基因抑制SRF-Pur？蛋白质复合物来激活平滑肌肌动蛋白（SM？A）和I型胶原蛋白？2-亚基启动子作为MFB分化过程的第一步。我们将测试的假设，SRF-Pur？由于PI 3 K/Akt前馈信号激酶过度活跃和/或次优MEK 1/Erk 1，2/Egr-1信号传导介导的反馈抑制作用受损，抑制复合物在PAH衍生的MFB中不稳定。在目的1中，我们提出了一个特点的转录激活因子和抑制剂的亚细胞区室化涉及动脉周围肌成纤维细胞分化和重塑IPAH/FPAH综合征使用免疫细胞化学方法。对于目标2，我们将定义的生化功能障碍，导致过度的动脉周围肌成纤维细胞分化IPAH/FPAH综合征使用表观遗传/代谢的方法，目标SRF-Pur？从正常或患病供体分离的肺动脉外膜成纤维细胞中的物理相互作用。我们已经开发了固相ELISA工具，以定量评估蛋白质：蛋白质和蛋白质：DNA的相互作用，独特地调节外膜MFB分化的过程。能够触发MFB中原型基因应答的专门转录调控复合物的组装代表了复杂血管疾病信号传导的汇聚点，该信号传导由多个补偿和患者特异性控制层组成。我们期望所获得的知识可以进一步基本了解限速相互作用，促进动脉顺应性的损失，通常与最具破坏性的IPAH/FPAH疾病综合征。未来对激活-阻遏动态相互作用的蛋白质生物化学的详细分析可能揭示肺动脉疾病和右心衰竭治疗管理的新靶点，最终可能改善患者的长期生存。 公共卫生关系：血管壁中的基因激活由蛋白质：蛋白质和蛋白质：DNA复合物控制，这些复合物是感染或物理创伤后快速伤口愈合和组织修复所必需的。当这些过程在心肺系统中变得异常或功能障碍时，过量的瘢痕组织会积聚并堵塞非常小的血管，最终减慢正常的血流，导致凝块形成、中风、组织梗塞（退化）和猝死。控制肺部伤口愈合的蛋白质复合物在肺动脉高压患者中可能是错误的，如果不治疗，最终会损害心脏的右侧，该右侧充当肺的血泵。拟议的研究将检查这些调节复合物的蛋白质成分，并确定与诊断为终末期肺动脉高压的患者相比，它们在正常个体中是否不同。这项拟议的研究可能会导致设计新的治疗策略，用于这种毁灭性的肺血管疾病，这种疾病无法治愈，只能通过肺移植手术治疗。(End摘要）