Caveolin-1, Caveolae and Placental Angiogenesis

Caveolin-1、Caveolae 和胎盘血管生成

• 批准号: 6915167
• 负责人: DONGBAO CHEN
• 金额: $ 30.8万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6915167
• 关键词: angiogenesis; biological signal transduction; caveolas; caveolins; cell cycle; cell differentiation; cell migration; cell proliferation; gene induction /repression; genetic regulation; growth factor receptors; immunoprecipitation; mitogen activated protein kinase; nitric oxide; phosphatidylinositol 3 kinase; placenta; protein localization; protein protein interaction; receptor binding; tissue /cell culture; transfection /expression vector; vascular endothelial growth factors

DESCRIPTION (provided by applicant): The overall hypothesis is that caveolin-1 (cav-1) interacts with vascular endothelial growth factor (VEGF) receptors (VEGFR) directly and/or indirectly to concentrate VEGFR initiated signaling events, i.e., Ras-Raf-MEK1-ERK2/1 and PI3K/Akt signaling modules, in the caveolae of endothelial cells (EC), thereby modulating VEGF regulation of EC proliferation, migration, and differentiation. Moreover, cav-1/caveolae may regulate placental angiogenesis by modifying the bioavailability of nitric oxide (NO) in EC. To address this hypothesis, an ovine fetoplacental artery EC model and a human placental capillary endothelial cell line will be used. Specific Aim 1: To further clarify if VEGFRs (i.e., KDR, Flt-1, and NP-1) are physically associated with cav-1 in vitro and in vivo, thus localized in the caveolae, and if overexpression of exogenous cav-1 or targeted down-regulation of endogenous cav-1 regulates ligand-dependent VEGFR activation. Specific Aim 2: To determine if targeted down-regulation of endogenous cav-1 or overexpression of exogenous cav-1 alters VEGF stimulation of cell cycle entry, proliferation, migration and differentiation. Specific Aim 3: To determine if VEGF activates the Ras/Raf/ERK2/1 and PI3K/Akt signaling modules in the caveolae. Specific Aim 4: To delineate if down-regulation of cav-1 or cav-1 overexpression modulates VEGF stimulation of MAPK and PI3K/Akt signaling pathways and the role of these pathways in VEGF-induced cell cycle entry, cell proliferation, migration, and differentiation. Specific Aim 5: To determine if targeted down-regulation of endogenous cav-1 or overexpresison of exogenous cav-1 alters eNOS activity thereby altering the bioavaibility Iof NO, which in turn regulates placental angiogenesis. These studies will have a great impact on our understanding of caveoli, VEGF/VEGFR, endothelial, and angiogenesis biology, all are biologically important fields we have integrated in the proposal clinically relevant to placental angiogenesis and vasodilatation for the first time. The ultimate clinical importance of this research is evident when one considers that uteroplacental endothelial adaptations to pregnancy, especially the rises in fetoplacental and uteroplacental perfusion, are linked directly to fetal growth and survivability and that these mechanisms are dysfunctional in pathologic pregnancies such as preeclampsia and IUGR.

描述（由申请人提供）：总体假设是caveolin-1（cav-1）与血管内皮生长因子（VEGF）受体（VEGFR）直接和/或间接相互作用以集中VEGFR启动的信号传导事件，即Ras-Raf -MEK1-ERK2/1 和 PI3K/Akt 信号模块，位于内皮细胞 (EC) 的小窝中，从而调节 VEGF 对 EC 增殖、迁移和生长的调节差异化。此外，cav-1/caveolae 可能通过改变 EC 中一氧化氮 (NO) 的生物利用度来调节胎盘血管生成。为了解决这一假设，将使用绵羊胎儿胎盘动脉 EC 模型和人胎盘毛细血管内皮细胞系。具体目标 1：进一步阐明 VEGFR（即 KDR、Flt-1 和 NP-1）在体外和体内是否与 cav-1 有物理相关性，从而定位于小凹，以及外源性 cav-1 是否过度表达或内源性 cav-1 的靶向下调可调节配体依赖性 VEGFR 激活。具体目标 2：确定内源性 cav-1 的靶向下调或外源性 cav-1 的过表达是否会改变 VEGF 对细胞周期进入、增殖、迁移和分化的刺激。具体目标 3：确定 VEGF 是否激活小窝中的 Ras/Raf/ERK2/1 和 PI3K/Akt 信号模块。具体目标 4：阐明 cav-1 或 cav-1 过表达的下调是否会调节 VEGF 对 MAPK 和 PI3K/Akt 信号通路的刺激，以及这些通路在 VEGF 诱导的细胞周期进入、细胞增殖、迁移和细胞增殖中的作用。差异化。具体目标 5：确定内源性 cav-1 的定向下调或外源性 cav-1 的过度表达是否会改变 eNOS 活性，从而改变 NO 的生物利用度，进而调节胎盘血管生成。这些研究将对我们对小窝、VEGF/VEGFR、内皮细胞和血管生成生物学的理解产生重大影响，所有这些都是生物学上重要的领域，我们首次将其纳入与胎盘血管生成和血管舒张临床相关的提案中。当人们认为子宫胎盘内皮对妊娠的适应，特别是胎儿胎盘和子宫胎盘灌注的增加，与胎儿生长和存活率直接相关，并且这些机制在先兆子痫和IUGR等病理性妊娠中功能失调时，这项研究的最终临床重要性是显而易见的。