Reno-protection afforded by combinatory approach targeting AT2R and neprilysin in obesity

针对肥胖症中 AT2R 和脑啡肽酶的组合方法提供的 Reno 保护

• 批准号: 10247019
• 负责人: Elizabeth Gray
• 金额: $ 2.87万
• 依托单位: UNIVERSITY OF HOUSTON
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-12 至 2022-06-11
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10247019
• 关键词: ACE2; Accreditation; Agonist; Albumins; Albuminuria; Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Atrial Natriuretic Factor; Attenuated; Binding; Biochemical; Biological; Blood Pressure; Blood Pressure Monitors; Cardiovascular Physiology; Cardiovascular system; Chronic; Clinical; Combined Modality Therapy; Creatinine; Data; Diabetes Mellitus; Diet; EFRAC; Enalapril; Female; Future; Glomerular Filtration Rate; Heart failure; Histologic; Hypertension; Impairment; In Vitro; Incubated; Individual; Injury; Injury to Kidney; Kidney; Knowledge; Laboratories; Liquid Chromatography; Mediating; Messenger RNA; Metabolism; Metalloproteases; Methods; Monitor; Natriuresis; Natriuretic Peptides; Neprilysin; Obesity; Obesity Related Hypertension; Outcome; Pathologic; Pathology; Peptide Metabolism; Peptide Receptor; Peptides; Peptidyl-Dipeptidase A; Periodic acid Schiff stain method; Pharmaceutical Preparations; Plasma; Prevalence; Process; Production; Proteins; Proteinuria; Public Health; Publishing; Rattus; Receptor, Angiotensin, Type 1; Renal function; Renin; Renin-Angiotensin System; Reporting; Research Project Grants; Risk; Risk Factors; Site; Sodium; Sodium Chloride; Stable Isotope Labeling; Stains; Structure; Suspensions; Telemetry; Testing; Therapeutic; Thinness; Type 2 Angiotensin II Receptor; Vasodilation; Work; Zucker Rats; comorbidity; hemodynamics; high salt diet; improved; inhibitor/antagonist; kidney cortex; kidney dysfunction; male; novel; novel strategies; novel therapeutics; obesity treatment; pre-doctoral; pressure; receptor; receptor expression; response; salt sensitive hypertension; sex; tandem mass spectrometry; treatment duration; urinary; valsartan

Abstract The increasing world-wide prevalence of obesity is a worrying public health problem and crisis. Coexistence of obesity, hypertension and diabetes significantly increases the risk of kidney dysfunction. In obesity, concentrations of angiotensin II (Ang II) increase, while those of Ang-(1-7) decrease along with activity of angiotensin converting enzyme 2 (ACE2). Neprilysin (NEP) and ACE2 are metallopeptidases that process Ang I and Ang II, respectively into the Mas receptor agonist, Ang-(1-7). The activity of these protective renin angiotensin system (RAS) components counterbalances the detrimental biological effects of the classical Ang II/angiotensin II type 1 receptor (AT1R) RAS axis. Recently published and preliminary data from our laboratory suggests that treatment with AT2R agonist compound 21 (C21) decreases Ang II and increases Ang-(1-7) in the kidney of obese Zucker rats, by increasing expression and activity of ACE2. Furthermore, our in vitro data suggests that AT2R agonist treatment decreases renin activity as well. Entresto, a dual AT1R blocker (valsartan) and neprilysin inhibitor (sacubitril) recently released to the market was found to be superior to enalapril therapy alone in the PARADIGM HF trial, resulting in its indication for heart failure with reduced ejection fraction. The benefits of Entresto are accredited to its ability to increase concentrations of atrial natriuretic peptide (ANP), another substrate of NEP, while blocking the increasing concentrations of Ang II from acting on AT1R. Yet, Entresto was found to cause an increase in the urinary albumin/creatinine ratio, an indicator of kidney injury. This knowledge along with our preliminary results led to our hypothesis that Ang-(1-7) level in obese kidney is decreased by NEP inhibition, with concurrent increase in Ang II. Combination therapy with C21 increases Ang- (1-7) and attenuates Ang II, by increasing ACE2 activity and expression. Moreover, C21 with NEP inhibition produces an additive effect on increasing ANP levels in obese kidney protecting function and structural integrity of the kidney. To test this hypothesis, Aim 1 is directed to determine the basal levels and basic metabolism of Ang peptides and ANP in obese kidney. Aim 2 will determine that combined treatment (short-term) with NEP inhibitor and AT2R agonist enhances ACE2 activity and Ang-(1-7) levels, and attenuates Ang II levels and ANP degradation in obesity. Aim 3 will determine that chronic combination therapy with a NEP inhibitor and AT2R agonist is reno-protective in salt-induced hypertension in obesity and is superior to Entresto (ARB + NEP inhibitor). Female obese Zucker rats are included in aim 3 to investigate the sex specific outcomes of our novel combinatory approach and to determine if it is equally effective in both male and female obese Zucker rats. To accomplish these aims, Ang peptides will be quantified utilizing our new liquid chromatography tandem mass spectrometry method; biochemical, histological and hemodynamic approaches to study renal function/injury and telemetry for monitoring blood pressure. The proposed work will significantly contribute to understanding Ang metabolism in obesity and impact future clinical perspectives for a novel reno-protective therapeutic approach.

摘要 肥胖症在全球范围内的流行日益增加，是一个令人担忧的公共卫生问题和危机。并存 肥胖、高血压和糖尿病会显著增加肾功能障碍的风险。在肥胖症中， 血管紧张素II（Ang II）的浓度增加，而Ang-（1-7）的浓度随着血管紧张素II（Ang II）活性的增加而沿着降低。 血管紧张素转换酶2（ACE 2）。脑啡肽酶（NEP）和ACE 2是加工Ang的金属肽酶 I和Ang II分别转化为Mas受体激动剂Ang-（1-7）。这些保护性的肾素的活性 血管紧张素系统（RAS）成分抵消了经典的Ang II/血管紧张素II 1型受体（AT 1 R）RAS轴。我们实验室最近发表的初步数据 表明用AT 2 R激动剂化合物21（C21）处理降低了Ang II并增加了Ang-（1-7）， 肾脏的肥胖Zucker大鼠，通过增加表达和活性的ACE 2。此外，我们的体外数据 表明AT 2 R激动剂治疗也降低了肾素活性。Entresto ®，一种双重AT 1 R阻滞剂（缬沙坦） 最近上市的脑啡肽酶抑制剂（沙库巴曲）被发现上级依那普利治疗 在PARADIGM HF试验中单独使用，导致其适应症为射血分数降低的心力衰竭。的 Entresto的益处被认为是其增加心房利钠肽（ANP）浓度的能力， NEP的另一种底物，同时阻断浓度增加的Ang II作用于AT 1 R。然而， 发现Entresto可导致尿白蛋白/肌酐比值增加，这是肾损伤的指标。 这一知识沿着我们的初步结果，导致我们的假设，即在肥胖的肾脏血管紧张素-（1-7）水平是 通过NEP抑制降低，同时增加Ang II。与C21的联合治疗增加了Ang-1的表达。 (1-7)并通过增加ACE 2活性和表达来减弱Ang II。此外，C21与NEP抑制 对增加肥胖肾脏保护功能和结构完整性的ANP水平产生累加效应 肾脏的为了验证这一假设，目标1旨在确定以下物质的基础水平和基础代谢： 血管紧张素肽和心钠素在肥胖肾脏中的作用目标2将确定联合治疗（短期）与NEP 抑制剂和AT 2 R激动剂增强ACE 2活性和Ang-（1-7）水平，并降低Ang II水平和ANP 肥胖症的恶化。目的3将确定NEP抑制剂和AT 2 R的长期联合治疗 激动剂对盐诱导的肥胖性高血压具有肾脏保护作用，且其作用上级优于恩格列净（ARB + NEP 抑制剂）。雌性肥胖Zucker大鼠被包括在目标3中，以研究我们的新方法的性别特异性结果。 本发明的目的是通过组合方法来确定其在雄性和雌性肥胖Zucker大鼠中是否同样有效。到 为了实现这些目标，我们将利用我们新的液相色谱串联质谱法对血管紧张素肽进行定量。 光谱法;研究肾功能/损伤的生化、组织学和血流动力学方法， 用于监测血压的遥测技术。本文的工作将有助于进一步理解Ang 肥胖症的代谢和影响未来的临床前景的一种新的肾脏保护治疗方法。