ESTROGEN RECEPTOR REGULATION OF NO SYNTHASES

无合酶的雌激素受体调节

• 批准号: 6858700
• 负责人: MICHAEL E MENDELSOHN
• 金额: $ 24.76万
• 依托单位: TUFTS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-01 至 2005-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6858700
• 关键词: biological signal transduction; enzyme activity; enzyme induction /repression; enzyme inhibitors; estrogen receptors; estrogens; gene expression; gene targeting; genetically modified animals; hormone regulation /control mechanism; laboratory mouse; mitogen activated protein kinase; myocardial ischemia /hypoxia; nitric oxide; nitric oxide synthase; protein structure function; protein tyrosine kinase; receptor expression; tissue /cell culture; transcription factor; vascular endothelium; vascular smooth muscle; vasodilatation; vasomotion

As described in the Introduction to this SCOR application, it is now recognized that estrogen directly affects the vasculature in two principal ways: estrogen causes rapid vasodilation, and estrogen activates gene expression and longer-term changes in blood vessel cells. Both the rapid and the longer-term effects of estrogen are thought to be important to the cardiovascular protective effects of the hormone. Project 4 of this SCOR is based on extensive unpublished preliminary data and explores a specific hypothesis related directly to the overall SCOR hypothesis: estrogen receptors mediate both rapid (non-genomic) activation and longer-term (genomic) expression of nitric oxide synthase (NOS) enzymes, affording protection against ischemic cardiovascular diseases and their sequelae. In Specific Aim 1, the mechanism of rapid (non- genomic) endothelial NOS activation by estrogen is explored, based on new data demonstrating that eNOS activation by estrogen in endothelial cells is mediated by an entirely novel function of the estrogen receptor ERalpha, a protein thought until now to function solely as a transcription factor. Signaling events mediating the rapid activation of eNOS by ERalpha are explored in endothelial and COS cell studies of (a) structure- function of ERalpha domains and residues mediating rapid activation of eNOS by estrogen; (b) ERalpha-mediated activation of eNOS via the MAP kinase pathway; and (c) Involvement of Src kinase in mediating ERalpha stimulation of eNOS. In Specific Aim 2, the longer-term, genomic actions of estrogen to protect against vascular injury are explored by studies of estrogen-mediated increases in vascular iNOS gene expression. These studies are based on extensive new data that strongly support that ERbeta induction of VSMC iNOS is critical to estrogen's vascular protective effects. This hypothesis is tested in Specific Aim 2 with studies of (a) ERbeta regulation of iNOS gene expression in cultured VSMC from WT, ERalpha KO and ERbeta KO mice; (b) vasomotion in endothelium-denuded mouse vascular rings from WT, ERalphaKO, ERbetaKO and iNOS KO mice; and (c) Estrogen effects on the vascular injury response to iNOS KO mice. By examining the role of estrogen receptors in both the rapid, non-genomic and longer-term, genomic effects of estrogen on vascular eNOS and iNOS, respectively, Project 4 reflects the overall hypothesis for this SCOR proposal and directly complements studies proposed in SCOR Projects 1, 2, 3 and 5.

如该SCOR应用的引言中所述，现在已经认识到雌激素直接以两种主要方式直接影响脉管系统：雌激素会导致快速血管舒张，雌激素激活血管细胞的基因表达和长期变化。雌激素的快速和长期作用都被认为对激素的心血管保护作用很重要。该SCOR的项目4基于广泛的未发表的初步数据，并探讨了与总体SCOR假设直接相关的特定假设：雌激素受体均介绍了快速（非基因组）激活和一氮氧化物合成酶（NOS）酶（NOS）酶（NOS）酶的快速（非基因组）的表达，可防止无皮质的Cardiepculcarculareae和他们的序列化和他们的序列化。在特定的目标1中，基于新数据表明，雌激素在内皮细胞中eNOS激活的eNOS激活介导了雌激素受体Eralpha的全新功能，该功能是由蛋白质的全新功能介导的，直到现在，蛋白质直到现在就可以单独作为转录因子发挥作用。在（a）eralpha结构域的结构和cos细胞的研究中探索了eralpha快速激活ENOS的信号传导事件 - eralpha结构域的结构和残基介导雌激素快速激活eNOS的残基； （b）通过MAP激酶途径的Eralpha介导的eNOS激活； （c）SRC激酶参与介导ERALPHA刺激ENOS的参与。在特定的目标2中，通过研究血管iNOS基因表达中雌激素介导的增加的增加，探索了雌激素对预防血管损伤的长期基因组作用。这些研究基于广泛的新数据，强烈支持ERBETA诱导VSMC Inos对于雌激素的血管保护作用至关重要。该假设在特定的目标2中进行了测试，研究了（a）来自WT，Eralpha KO和Erbeta KO小鼠培养的VSMC中iNOS基因表达的ERBETA调节； （b）来自WT，Eralphako，Erbetako和Inos KO小鼠的内皮抑制小鼠血管环的血管舒张； （c）雌激素对iNOS KO小鼠血管损伤反应的影响。通过研究雌激素受体在雌激素对血管eNOS和INOS的快速，非基因组和长期基因组作用中的作用，项目4反映了该SCOR建议的总体假设，并直接补充了SCOR项目1、2、3和5中提出的研究。