Extracellular ATP as regulator of hypoxia-induced vasa vasorum neovascularization

细胞外 ATP 作为缺氧诱导的滋养血管新生血管的调节剂

• 批准号: 8820276
• 负责人: Evgenia V Gerasimovskaya
• 金额: $ 48.13万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-10 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8820276
• 关键词: Adenine Nucleotides; Animals; Bioenergetics; Biological; Blood Cells; Blood Vessels; Cardiac; Cell Culture Techniques; Cell Respiration; Cells; Chronic; Data; Development; Disease; Endothelial Cells; Energy Metabolism; Exhibits; Glycolysis; Goals; Growth; Health; Human; Hypoxia; Infiltration; Inflammatory; Life; Link; Lung; MAPK3 gene; Mediating; Metabolic; Metabolism; Mitochondria; Modeling; Molecular; Neonatal; Nucleotides; Pathogenesis; Pathologic Neovascularization; Pathway interactions; Phenotype; Physiological; Play; Population; Pulmonary Circulation; Pulmonary Hypertension; Pulmonary artery structure; Purinoceptor; Rattus; Regulation; Reporting; Research Proposals; Role; Signal Pathway; Signal Transduction; Source; Stem cells; Stimulus; Testing; Translating; Tunica Adventitia; Vascular Diseases; Vascular Endothelial Cell; Vascular remodeling; Warburg Effect; Work; angiogenesis; autocrine; cell type; clinically relevant; density; effective therapy; extracellular; human FRAP1 protein; innovation; neovascularization; paracrine; progenitor; pulmonary arterial hypertension; receptor-mediated signaling; response; vasa vasorum; vasculogenesis

DESCRIPTION (provided by applicant): Pathological vascular remodeling is a key component and frequently life-threatening consequence, of vascular diseases in both the systemic and pulmonary circulation. In a neonatal model of hypoxic pulmonary hypertension, we have previously reported tha We have previously reported that similar to humans with IPAH, hypoxia-induced pulmonary artery (PA) remodeling is associated with marked increases in the density of vasa vasorum (VV) network, recruitment and infiltration of circulating progenitor and inflammatory cells to the PA, implicating VV in disease pathogenesis. The long-term goal of our studies is to evaluate cellular mechanisms and endogenous molecular factors that mediate vasa vasorum neovascularization in hypoxia-induced pulmonary vascular remodeling. Extracellular adenine nucleotides are increasingly recognized as important regulators of vascular functions. We demonstrated that the adventitial vasa vasorum endothelial cells (VVEC) are a potent source of extracellular ATP, which acts as an autocrine/paracrine factor mediating hypoxia-induced VVEC angiogenesis. Our data demonstrated that exaggerated nucleotide-mediated angiogenic responses in VVEC involve activation of P2Y1, and P2Y13 purinergic receptors, PI3K/Akt/mTOR, ERK1/2, and the elevation of cytoplasmic, nucleoplasmic, and mitochondrial Ca2+. In addition, our preliminary data for this proposal we demonstrated the presence of subsets of P2Y13R expressing highly proliferative potential colony forming cells (VVECFC) in VVEC cultures, which might be responsible for angiogenic VV expansion. As the importance of cellular energy metabolism has been postulated to link cellular metabolic state and functional responses, in this proposal we will test the hypothesis that purinergic regulation of VV angiogenesis involves the activation of mitogenic and bioenergetic pathways in VVEC and VVECFC, leading to metabolic reorgnization/reprogramming and phenotypical changes in these cells towards differentiated endothelial phenotype. The studies proposed in three specific aims will: (i) Characterize a hierarchy of colony-forming cells residing in VVEC; determine their phenotype, proliferative and angiogenic capabilities; (ii) examine purinergic receptor-mediated signaling pathway in clonogenic, angiogenic, and signaling responses in VVEC and VVECFC; (iii) determine bioenergetic organization of VVEC and VVECFC and determine whether extracellular nucleotides and hypoxia induce angiogenic and phenotypic responses in these cells via energy metabolism and mitochondrial regulation. Ultimately, this research proposal aspires to translate fundamental questions of purinergic signaling to the clinically relevant problem of hypoxia-induced angiogenesis. Understanding of fundamental biological mechanisms of metabolic and signaling regulation of VV expansion to a functional vascular network will facilitate development of the innovative treatments for pulmonary hypertension and a variety of vascular diseases that involve impaired angiogenesis and pathologic vascular remodeling.

描述（由申请人提供）：病理性血管重塑是全身和肺循环血管疾病的关键组成部分，并且常常危及生命。在新生儿缺氧性肺动脉高压模型中，我们之前报道过，与患有IPAH的人类类似，缺氧诱导的肺动脉（PA）重塑与血管滋养管（VV）网络密度的显着增加、循环祖细胞和炎症细胞向PA的募集和浸润相关，表明VV在疾病发病机制中的作用。我们研究的长期目标是评估缺氧诱导的肺血管重塑中介导血管滋养管新生血管形成的细胞机制和内源性分子因素。细胞外腺嘌呤核苷酸越来越被认为是血管功能的重要调节剂。我们证明外膜血管滋养内皮细胞（VVEC）是细胞外 ATP 的有效来源，其作为介导缺氧诱导的 VVEC 血管生成的自分泌/旁分泌因子。我们的数据表明，VVEC 中夸大的核苷酸介导的血管生成反应涉及 P2Y1 和 P2Y13 嘌呤能受体、PI3K/Akt/mTOR、ERK1/2 的激活以及细胞质、核质和线粒体 Ca2+ 的升高。此外，我们针对该提案的初步数据表明，VVEC 培养物中存在表达高度增殖潜力集落形成细胞 (VVECFC) 的 P2Y13R 子集，这可能是血管生成 VV 扩张的原因。由于细胞能量代谢的重要性被假定为连接细胞代谢状态和功能反应，在本提案中，我们将测试以下假设：VV 血管生成的嘌呤能调节涉及 VVEC 和 VVECFC 中有丝分裂和生物能途径的激活，导致这些细胞的代谢重组/重编程和表型变化，向分化的内皮表型发展。提出的研究有三个具体目标： (i) 表征 VVEC 中集落形成细胞的层次结构；确定它们的表型、增殖和血管生成能力； (ii) 检查 VVEC 和 VVECFC 中克隆形成、血管生成和信号反应中嘌呤能受体介导的信号传导途径； (iii)确定VVEC和VVECFC的生物能组织，并确定细胞外核苷酸和缺氧是否通过能量代谢和线粒体调节诱导这些细胞中的血管生成和表型反应。最终，这项研究计划旨在将嘌呤能信号传导的基本问题转化为缺氧诱导的血管生成的临床相关问题。了解 VV 扩张到功能性血管网络的代谢和信号调节的基本生物学机制将有助于开发肺动脉高压和涉及血管生成受损和病理性血管重塑的各种血管疾病的创新疗法。