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Therapeutic Potential of EPO and its Derivatives for Reducing Blood Pressure

EPO 及其衍生物降低血压的治疗潜力

基本信息

批准号：
9147229
负责人：
Edward Lakatta
金额：
$ 15.43万
依托单位：
NATIONAL INSTITUTE ON AGING
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/9147229
关键词：
Abdominal Cavity Acute Adverse effects Anemia Animal Experiments Animals Anti-Inflammatory Agents Anti-inflammatory Antihypertensive Agents Aorta Apoptotic Area Arteries Attenuated Binding Blast Cell Blood Cells Blood Pressure Blood Pressure Monitors Blood Vessels Breathing Cardiac Cardiac Myocytes Cardiovascular system Catheters Control Groups Coronary Coronary artery Dahl Hypertensive Rats Data Development Diet Dose Equilibrium Erythrocytes Erythropoietin Erythropoietin Receptor Excision Experimental Models Glycoproteins Heart failure Hormones Hour Human Hypertension Implant Inbred SHR Rats Indwelling Catheter Infusion procedures Inhibition of Apoptosis Injection of therapeutic agent Intravenous Isoflurane Kidney Diseases Left ventricular structure Life Expectancy Ligation Maintenance Measures Mediating Medical Mitochondria Modeling Molecular Structure Myocardial Infarction Myocardial Ischemia NG-Nitroarginine Methyl Ester Nephrosclerosis Nerve Tissue Nitric Oxide Nitric Oxide Pathway Nitric Oxide Signaling Pathway Nitric Oxide Synthetase Inhibitor Pathway interactions Peptides Performance Peripheral Permeability Pharmaceutical Preparations Pharmacologic Substance Process Production Property Publishing Pump Rattus Reactive Oxygen Species Recombinant Erythropoietin Recombinants Regulation Renal Mass Reporting Research Risk Factors Role Saline Sodium Chloride Sodium-Restricted Diet Stress Stroke Surface Tail Techniques Telemetry Testing Therapeutic Time Tissues Translations Vasodilation Wistar Rats Writing base blood pressure reduction blood pressure regulation clinical practice coronary fibrosis hemodynamics intravenous injection myocardial infarct sizing normotensive novel therapeutic intervention pre-clinical pressure prevent programs receptor recombinant human erythropoietin research study response sensor

项目摘要

The broad objective of this program is to explore the vasodilative potential of rhEPO and its non-erythropoietic derivatives and to perform preclinical animal experiments on different models of arterial hypertension to elucidate their mechanism of action and to evaluate their potential for translation into clinical practice in humans. I. Acute hemodynamic effects of EPO. Recently published research strongly suggests the erythropoietin binds to a Common receptor and therefore activates anti-apoptotic, anti-inflammatory pathways, and nitric oxide release. Surprisingly, hemodynamic response subsequent to NO activation after EPO administration had never been reported. Objectives of this study were to evaluate the acute hemodynamic and cardiovascular responses to EPO administration, to confirm their NO association, and to test the hypothesis that EPO-induced cardioprotection is mediated through cardiovascular changes related to NO activation. In Experiment 1 after 3000 U/kg of rhEPO was administered intravenously to Wistar rats, arterial blood pressure, monitored via indwelling catheter, almost immediately started progressively to decline, until leveling off 90 minutes after injection at 20% below control level. In Experiment 2 the 25% reduction of mean blood pressure, compared to control group, was observed 2 hrs after intravenous injection of either 3000 or 150 U/kg of rhEPO. Detailed pressure volume loop analyses of cardiac performance (Experiment 3) 2 hrs after intravenous injection of human or rat recombinant EPO (3000U/kg) revealed a significant reduction of systolic function (PRSW was 33% less than control). Reduction of arterial blood pressure and systolic cardiac function in response to rhEPO were blocked in rats pretreated with a non-selective inhibitor of nitric oxide synthase (L-NAME). In Experiment 4, 24 hrs after a permanent ligation of a coronary artery myocardial infarction (MI) measured 263.5% of left ventricle in untreated rats. MI in rats treated with 3000 U/kg of rhEPO immediately after coronary ligation was 56% smaller. Pretreatment with L-NAME did not attenuate the beneficial effect of rhEPO on MI size, while MI size in rats treated with L-NAME alone did not differ from control. Therefore, a single injection of rhEPO resulted in a significant, NO-mediated reduction of systemic blood pressure and corresponding reduction of cardiac systolic function. However, EPO-induced protection of myocardium from ischemic damage is not associated with NO activation or NO-mediated hemodynamic responses. II. Antihypertensive properties of non-erythropoietic derivatives of EPO A small peptide, Helix B Surface Peptide (HBSP), also known as ARA290, was synthesized by Araim Pharmaceutical on the basis of a part of the EPO molecule. This peptide binds to a common receptor, EPO receptor hetherocomplex, and does not have pro-thrombotic effects. This peptide was tested in different experimental models and, while it proved to possess strong tissue protective properties, it did not induce blood cell production. Recently we demonstrated that HBSP has a similar potency to rhEPO for increasing the reactive oxygen species (ROS) threshold for induction of the mitochondrial permeability transition by 40%, thus protecting cardiac myocytes from ischemic stress. In the rat model of MI induced by a permanent ligation of the coronary artery, we also demonstrated the equal potency of a single administration of EPO and HBSP for a 50% reduction of resulting MI. In that experimental model the anti-apoptotic and anti-inflammatory potentials of HBSP were equal to those of rhEPO. In the first experiment, under Isoflurane inhalation narcosis, after recording of arterial blood pressure via catheter inserted into the aorta, we administered either a single intravenous dose of 60 mcg of HBSP (ARA290) or a saline to a normotensive rat. Two hours later the Isoflurane was reintroduced and arterial blood pressure was again measured. The blood pressure after injection of peptide was about 20% lower than after injection of saline. The effect was similar to the effect of rhEPO that we previously reported and was blocked by pretreatment with L-NAME. In the second experiment the arterial blood pressure reducing effect of HBSP was tested in 3 different experimental rat models of hypertension. Osmotic pumps delivering 0.16 - 0.09 ug/min of HBSP for 8 weeks were implanted into the abdominal cavity of spontaneously hypertensive rats (SHR), salt sensitive Dahl rats consuming a high salt diet (HS), and Wistar rats subjected to a resection of 5/6 of the total renal mass (RMR). WKY, Dahl salt sensitive rats maintained on a low salt diet, and sham operated rats, respectively, served as controls for these 3 models. Blood pressure was measured under Isoflurane narcosis using tail cuff technique. In untreated groups of all three experimental models, systolic blood pressure (SBP) gradually increased to 180-200 mmHg. HBSP infusion completely normalized the SBP in SHR, reduced the SBP by 20% (from 190 to 150 mmHg) in RMR, and prevented the elevation of SBP in Dahl salt sensitive rats maintained on high salt diet. Significant myocardial fibrosis occurring in all 3 groups of untreated hypertensive rats was reduced to the level of controls by HBSP. Significant nephrosclerosis observed in all 3 untreated hypertensive groups was also reduced to the level of controls in treated Dahl and SHR, but not in RMR groups. These results clearly demonstrate potent antihypertensive and antifibrotic properties of HBSP. In order to investigate antihypertension effect of HBSP for long-term in un-anesthetized, freely-moving animals, during this reporting period, we used implantable blood pressure telemetry sensors in spontaneously hypertensive rats (SHR), treat one half of them with HBSP (0.16 - 0.09 ug/min via mini-osmotic pump) and other half with saline (via mini-osmotic pump) for 8 weeks. At the time this report is written, data are still in the process.

该计划的主要目的是探索rhEPO及其非红细胞生成衍生物的血管舒张潜力，并对不同的动脉高血压模型进行临床前动物实验，以阐明其作用机制，并评估其转化为人类临床实践的潜力。 I. EPO的急性血液动力学效应。最近发表的研究强烈表明，促红细胞生成素结合到一个共同的受体，因此激活抗凋亡，抗炎途径，和一氧化氮释放。令人惊讶的是，EPO给药后NO激活后的血流动力学反应从未报道过。本研究的目的是评估急性血液动力学和心血管反应EPO管理，以确认其NO协会，并测试的假设，EPO诱导的心脏保护是通过心血管的变化介导的NO激活。在实验1中，对Wistar大鼠静脉注射3000 U/kg rhEPO后，通过留置导管监测的动脉血压几乎立即开始逐渐下降，直到注射后90分钟稳定在低于对照水平20%。在实验2中，与对照组相比，在静脉注射3000或150 U/kg的rhEPO后2小时观察到平均血压降低25%。在静脉注射人或大鼠重组EPO（3000U/kg）后2小时，心脏性能的详细压力体积环分析（实验3）显示收缩功能显著降低（PRSW比对照低33%）。用非选择性一氧化氮合酶抑制剂（L-NAME）预处理大鼠，可阻断rhEPO对动脉血压和心脏收缩功能的降低。在实验4中，24小时后永久结扎冠状动脉心肌梗死（MI）测量263.5%的左心室在未经处理的大鼠。冠脉结扎后立即给予3000 U/kg rhEPO的大鼠MI降低了56%。用L-NAME预处理没有减弱rhEPO对MI大小的有益作用，而单独用L-NAME处理的大鼠的MI大小与对照组没有差异。因此，单次注射rhEPO导致显著的NO介导的全身血压降低和相应的心脏收缩功能降低。然而，EPO诱导的心肌缺血性损伤的保护与NO激活或NO介导的血流动力学反应无关。二.促红细胞生成素的非红细胞生成衍生物的抗高血压特性 Araim Pharmaceutical基于EPO分子的一部分合成了一种小肽，即受阻B表面肽（HBSP），也称为ARA 290。该肽与一种常见的受体EPO受体杂合物结合，并且不具有促血栓形成作用。这种肽在不同的实验模型中进行了测试，虽然它被证明具有很强的组织保护特性，但它不会诱导血细胞的产生。最近，我们证明，HBSP具有类似的效力rhEPO增加活性氧（ROS）阈值诱导线粒体通透性转换40%，从而保护心肌细胞缺血应激。在冠状动脉永久性结扎诱导的MI大鼠模型中，我们也证明了EPO和HBSP单次给药对MI减少50%的同等效力。在该实验模型中，HBSP的抗凋亡和抗炎潜力与rhEPO相当。在第一个实验中，在异氟烷吸入麻醉下，通过插入主动脉的导管记录动脉血压后，我们向血压正常的大鼠单次静脉注射60 mcg HBSP（ARA 290）或生理盐水。两小时后，再次引入异氟烷，并再次测量动脉血压。注射肽后的血压比注射盐水后低约20%。这种作用类似于我们以前报道的rhEPO的作用，并被L-NAME预处理所阻断。实验二采用3种不同的高血压大鼠模型，观察HBSP的降压作用。在自发性高血压大鼠（SHR）、食用高盐饮食的盐敏感性Dahl大鼠（HS）和切除总肾质量（RMR）5/6的Wistar大鼠的腹腔中植入持续8周递送0.16 - 0.09 μ g/min HBSP的渗透泵。WKY、Dahl盐敏感大鼠维持低盐饮食，假手术大鼠分别作为这3种模型的对照。在异氟醚麻醉下采用尾套法测量血压。在所有三种实验模型的未处理组中，收缩压（SBP）逐渐升高至180 - 200 mmHg。HBSP输注可使SHR的SBP完全正常化，使RMR的SBP降低20%（从190 mmHg降至150 mmHg），并防止维持高盐饮食的Dahl盐敏感大鼠的SBP升高。HBSP可使3组未治疗的高血压大鼠心肌纤维化程度降低至对照组水平。在所有3个未治疗的高血压组中观察到的显著肾硬化在治疗的Dahl和SHR中也降低到对照组的水平，但在RMR组中没有。这些结果清楚地证明了HBSP的有效抗高血压和抗纤维化特性。为了研究HBSP在未麻醉、自由活动的动物中的长期降压作用，在本报告期间，我们在自发性高血压大鼠（SHR）中使用植入式血压遥测传感器，其中一半用HBSP（0.16 - 0.09 μ g/min，通过微型渗透泵）治疗，另一半用盐水（通过微型渗透泵）治疗8周。在撰写本报告时，数据仍在处理中。