HORMONE REGULATION OF CARDIAC INJURY

心脏损伤的激素调节

• 批准号: 7609832
• 负责人: Eric J Smart
• 金额: $ 24.41万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-05-01 至 2008-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7609832
• 关键词: Affect; Agonist; Androgen Receptor; Binding; Biological Assay; Cardiac; Cardiac Myocytes; Caveolae; Caveolins; Cholesterol; Complex; Computer Retrieval of Information on Scientific Projects Database; Data; Dominant-Negative Mutation; Endothelium; Enzyme Inhibitor Drugs; Epidemiologic Studies; Estrogen Receptor alpha; Estrogen Replacements; Estrogens; Funding; Generations; Gonadal Steroid Hormones; Grant; Heart; High Density Lipoproteins; Injury; Institution; Knockout Mice; Mediating; Modification; Molecular; Myocardial Ischemia; Nitric Oxide; Nitric Oxide Synthase; Numbers; Orchiectomy; Ovariectomy; Process; Production; Reporting; Research; Research Personnel; Resources; Role; Source; Testing; Testosterone; United States National Institutes of Health; Wild Type Mouse; Woman; adenylate kinase; alpha caveolin; caveolin 1; hormone regulation; men; novel; uptake

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The central hypothesis of this proposal is that HDL-associated sex hormones (estrogen and testosterone) regulate the activity of cardiac myocyte constitutive nitric oxide synthase which subsequently affects the extent of ischemic injury. Epidemiological studies demonstrate that women are less prone to ischemic heart disease than men. The mechanisms responsible the differences in ischemic injury observed between men and women are not know although the current focus is on sex hormones, in particular estrogen and testosterone. A large number of studies have implicated estrogen-induced stimulation of constitutive nitric oxide synthase (cNOS) as providing protection against ischemic injury of cardiac myocytes. The role of testosterone is unclear with reports of protection against ischemic injury and reports of testosterone promoting ischemic injury. The majority of the studies on estrogen and testosterone do not distinguish between effects mediated by the endothelium in hearts and cardiac myocytes. One of the novel aspects of the proposed studies is that the preliminary data indicate that estrogen and testosterone have direct effects on cardiac myocytes, independent of the endothelium. Another novel aspect of the proposed studies is that it is estrogen or testosterone associated with HDL that is responsible for the generation of nitric oxide in cardiac myocytes and protection/promotion of ischemic injury. The molecular mechanism whereby estrogen limits ischemic injury and testosterone increases ischemic injury will be tested in two Aims. Aim 1: To determine the mechanism whereby HDL-associated estrogen stimulates the production of nitric oxide and limits ischemic injury. The preliminary studies suggest that estrogen receptor alpha and caveolin-1 form a complex that stimulates cNOS via AMP kinase. Cardiac myocytes isolated from wild type mice, caveolin-1 null mice, or estrogen receptor alpha null mice will be used along with dominant negative adenoviral constructs, agonist/antagonists, and enzyme assays to dissect the mechanism(s). In addition, wild type mice, SR-BI null mice, caveolin-1 null mice, and estrogen receptor alpha null mice along with ovariectomies and ovariectomies/estrogen replacement will be used to determine the effect on ischemic injury. Aim 2: To determine the mechanism whereby HDL-associated testosterone decreases the generation of nitric oxide and increases ischemic injury. The preliminary studies demonstrate that HDL-associated testosterone decreases the generation of nitric oxide without affecting the cellular levels of cNOS. Isolated cardiac myocytes will be used to examine several possible mechanisms for the HDL-testosterone mediated inhibition of cNOS such as, altered caveolin binding to cNOS, depletion of caveolae cholesterol, re-localization of cNOS, and modification of cNOS and/or caveolin-1. Additional studies will determine if the androgen receptor and/or testosterone uptake are involved in this process. Wild type mice, SR-BI null mice, and caveolin-1 null mice along with orchidectomies and orchidectomies/testosterone replacement will be used to determine the effect on ischemic injury.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 该提议的中心假设是HDL相关性激素（雌激素和睾丸激素）调节心肌细胞组成型一氧化氮合酶的活性，后来影响缺血性损伤的程度。 流行病学研究表明，女性比男性更容易患缺血性心脏病。 导致男女观察到的缺血性损伤差异的机制尚不知道，尽管目前的重点是性激素，尤其是雌激素和睾丸激素。 大量研究暗示了雌激素诱导的刺激组成型一氧化氮合酶（CNOS）是防止心肌细胞缺血性损伤的保护。 睾丸激素的作用尚不清楚，据报道，防止缺血性损伤的报道和睾丸激素促进缺血性损伤的报道。 关于雌激素和睾丸激素的大多数研究没有区分心脏内皮和心肌细胞中内皮介导的作用。 提出的研究的新方面之一是，初步数据表明雌激素和睾丸激素对与内皮无关的心肌细胞有直接影响。 拟议的研究的另一个新方面是，它是与HDL相关的雌激素或睾丸激素，导致心肌细胞中一氧化氮产生以及缺血性损伤的保护/促进。 雌激素限制缺血性损伤和睾丸激素增加缺血性损伤的分子机制将以两个目的进行测试。 目标1：确定与HDL相关的雌激素刺激一氧化氮和限制缺血性损伤的机制。 初步研究表明，雌激素受体α和小窝蛋白-1形成一种通过AMP激酶刺激CNO的复合物。 从野生型小鼠，小鼠-1 NULL小鼠或雌激素受体αNULL小鼠中分离出的心肌细胞将与显性的阴性腺病毒构建体，激动剂/拮抗剂和酶测定法一起使用，以剖析机制。 此外，野生型小鼠，SR-BI无效小鼠，小窝蛋白-1 null小鼠和雌激素受体αNULL小鼠以及卵巢切除术和卵巢切除术/雌激素替代将用于确定对缺血性损伤的影响。 目标2：确定与HDL相关睾丸激素减少一氧化氮并增加缺血性损伤的机制。 初步研究表明，与HDL相关的睾丸激素会降低一氧化氮的产生，而不会影响CNOS的细胞水平。 孤立的心肌细胞将用于检查HDL-托斯托酮介导的CNOS抑制的几种可能机制，例如，可以改变与CNOS的可窝结合，Caveolae胆固醇的消耗，CNOS的再定位，CNOS的重新定位以及CNOS和/或CNOS和/或/或/或或/或或/或或/或caveolin-1的改性。 其他研究将确定雄激素受体和/或睾丸激素是否参与此过程。 野生型小鼠，SR-BI无效小鼠和小窝蛋白-1无效小鼠以及兰花切除术和兰花切除术/睾丸激素的替代将用于确定对缺血性损伤的影响。