AMPK as a redox sensor and modulator

AMPK 作为氧化还原传感器和调制器

• 批准号: 7849800
• 负责人: MING-HUI ZOU
• 金额: $ 36.63万
• 依托单位: UNIVERSITY OF OKLAHOMA HLTH SCIENCES CTR
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7849800
• 关键词: 3-nitrotyrosine; 5' -AMP-activated protein kinase; Abbreviations; Acetylcholine; Actins; Address; Adenoviruses; Adipocytes; Adverse effects; Aging; Antibodies; Antioxidants; Aorta; Apolipoprotein E; Arachidonic Acids; Arterial Fatty Streak; Atherosclerosis; Biological Assay; Biology; Blood; Blood Vessels; CaM kinase I activator; Cardiovascular Diseases; Cardiovascular system; Catalytic Domain; Cell Adhesion Molecules; Cells; Cerebrum; Cholesterol; Chronic; Coronary; Cyclic GMP; Data; Detection; Development; Diabetes Mellitus; Dimensions; Disease; Dominant-Negative Mutation; E-Selectin; Endothelial Cells; Endothelium; Energy Metabolism; Environmental Tobacco Smoke; Enzymes; Epoprostenol; Equilibrium; Etiology; Eukaryotic Cell; Event; Exhibits; Exposure to; Functional disorder; Generations; Genetic; Glucose; Goals; Health; Hepatocyte; Human; Hypertension; Hypertriglyceridemia; Hypoxia; ICAM1 gene; Incubated; Inflammation; Inflammatory; Ischemic Preconditioning; Knock-out; Knockout Mice; Lesion; Link; Lipid Peroxidation; Lipids; Mediating; Medicine; Metabolism; Metformin; Modeling; Molecular; Motion; Mus; NADPH Oxidase; NG-Nitroarginine Methyl Ester; Nicotine; Nicotinic Receptors; Nitric Oxide; Obesity; Oxidants; Oxidases; Oxidation-Reduction; Peripheral; Peroxonitrite; Phenotype; Phosphotransferases; Physiological; Plasma; Play; Polyethylene Glycols; Process; Production; Prostacyclin synthase; Prostaglandins; Prostaglandins I; Protein Kinase C; Protein-Serine-Threonine Kinases; Rattus; Reaction; Reactive Nitrogen Species; Reactive Oxygen Species; Relative (related person); Relaxation; Resistance; Risk Factors; Role; Signal Transduction; Smoke; Smoker; Smoking; Smooth Muscle; Stimulus; Stress; Superoxide Dismutase; Superoxides; System; Thromboxane Receptor; Transgenic Mice; Triglycerides; Tyrosine; Vascular Cell Adhesion Molecule-1; Western Blotting; Whole Organism; Wild Type Mouse; acetovanillone; arginine methyl ester; atherogenesis; biological adaptation to stress; cardiovascular disorder risk; cardiovascular risk factor; catalase; cell growth regulation; cigarette smoking; cigarette smoking; exposed human population; genetic manipulation; human CYBA protein; human NOS3 protein; hypercholesterolemia; imidazole-4-carboxamide; improved; in vivo; inhibitor/antagonist; insight; mouse model; mutant; neutrophil cytosol factor 67K; novel; overexpression; oxidant stress; polyethylene glycol-superoxide dismutase; premature; prevent; progesterone 11-hemisuccinate-(2-iodohistamine); promoter; public health relevance; response; riboside; sensor; stressor; tetrahydrobiopterin; therapeutic target

DESCRIPTION (provided by applicant): AMPK is a serine/threonine protein kinase involved in the regulation of cellular and organismal metabolism. The AMPK system acts as a sensor of cellular energy status that is conserved in all eukaryotic cells. AMPK has been suggested to serve as an energy gauge in cells, by detecting changes in the ratios of AMP to ATP. The consequences of AMPK activation include inhibition of ATP-consuming processes and activation of an ATP-producing process. The applicant's group was the first to demonstrate that physiologically relevant concentrations of ONOO- increased AMPK activity as well as its downstream enzymes such as eNOS and acetyl Co-A carboxylase (ACC). In addition, we have also demonstrated that ONOO--dependent AMPK activation is operative in hypoxia-reoxygenation, metformin- stimulated endothelial cells, thromboxane receptor stimulation, and nicotine-treated adipocytes. Similarly, we found that nicotine, a major constituent of cigarette smoke, activates AMPK in differentiated 3T3L1 adipocytes in a ROS-dependent fashion. Interestingly, AMPK activation by pharmacological AMPK activators (AICAR and metformin), physiological stimuli (glucose-depletion and osmotic stress), or genetic manipulation (adenoviruses encoding constitutively active AMPK) protects the endothelium against the adverse effects of nicotine. Concomitantly, pharmacological or genetic inhibition of AMPK markedly increased ROS, NF?B, and inflammatory genes (ICAM-1, VCAM-1, and E-selectin) in cultured endothelial cells, differentiated 3T3L1 adipocytes, and cultured primary rat hepatocytes. In parallel, in supporting that AMPK functions as a suppressor of oxidant stress, we have obtained preliminary evidence suggesting that AMPK activation by ischemic preconditioning (IPC) effectively blocked hypoxia/reoxygenation-triggered oxidant stress. The most conclusive evidence that AMPK reduced oxidant stress is that IPC failed to alter both the markers of oxidant stress and endothelial function in the AMPK 11 knockout (KO) mice. Consistently, we have found that compared to the wild types, aortas isolated from AMPK 11 or 12 KO mice exhibited impaired endothelial relaxation together with increased detections of both O2.- and ONOO-. Similarly, there was greater levels of NADPH oxidase subunits including gp91phox (NOX2), NOX-4, p22phox, p47phox, and p67phox together with increased NAD(P)H oxidase activity in AMPK12 KO mice than those in C57BL6 wild types. Importantly, apocynin, a potent NAD(P)H oxidase inhibitor, restored acetylcholine-induced endothelium-dependent relaxation in AMPK 12 KO mice, further suggesting NAD(P)H oxidase is functionally active and is responsible for impaired endothelial function in AMPK 12KO mice. Finally, without altering plasma lipids (cholesterol and triglyceride), the aortas isolated from Apo-E/AMPK11 or AMPK/AMPK 12 dual KO mice exhibited increased detection of oxidant stress markers, increased atherosclerotic lesions, and increased expression of proinflammatory adhesion molecules when compared to those in Apo-E KO mice. The goal of this application is to establish (a) that AMPK, through its ability to respond to very small changes in AMP levels, may be the proximal "oxidant stress-sensor" of the cell; (b) that AMPK activation may trigger physiological responses to suppress processes that generate oxidants (modulator) and or increase anti-oxidant defense systems; and (c) AMPK, via a reduction of oxidant stress, maintains the non-angiogenic, non-inflammatory, and atherosclerosis-resistant phenotypes in vascular cells. PUBLIC HEALTH RELEVANCE: A basic premise of this proposal is that AMPK activation could protect cells and the whole organism against the adverse effects of cardiovascular risk factors such as nicotine by setting in motion events that decrease oxidant stress. For the sake of clarity and being focused of the current application we use nicotine as a pathological stimulus relevant to cardiovascular diseases. As there is growing evidence that oxidant stress is involved in the vascular effects of cardiovascular risk factors including hypercholesterolemia, diabetes, and hypertension, thus, the significance of this proposal is beyond nicotine and will be applicable to other cardiovascular diseases. The current application addresses a fundamental question in biology and medicine, i.e., how oxidant stressors are sensed and modulated in health and disease. Completion of this application, thus, may add an entirely new dimension to the role of AMPK in stress responses and provide an interface between oxidant stress, energy metabolism, and cardiovascular biology. Completion of the proposed studies will provide novel insights into whether AMPK is a potential target for therapy in smoking and common diseases including aging, obesity, diabetes, hypertension, and atherosclerosis.

描述（由申请人提供）：AMPK是参与细胞和生物代谢调节的丝氨酸/苏氨酸蛋白激酶。 AMPK系统充当了在所有真核细胞中保守的细胞能量状态的传感器。有人建议通过检测AMP与ATP的比率变化来充当细胞中的能级。 AMPK激活的后果包括抑制ATP消耗过程和激活ATP产生过程。申请人的组是第一个证明了与生理相关的ONOO-AMPK活性及其下游酶（例如eNOS和乙酰基Co-A Co-A羧化酶（ACC））。此外，我们还证明了ONOO依赖性AMPK激活在缺氧 - 抗氧化，二甲双胍刺激的内皮细胞，血栓烷受体刺激和尼古丁处理的脂肪细胞中可操作。同样，我们发现尼古丁是香烟烟雾的主要成分，它以ROS依赖的方式激活了分化的3T3L1脂肪细胞的AMPK。有趣的是，药物AMPK激活剂（AICAR和二甲双胍），生理刺激（葡萄糖 - 脱发和渗透胁迫）或遗传操纵（编码腺病毒构造主动AMPK）的AMPK激活可保护尼古丁的不良影响。同时，在培养的内皮细胞中，AMPK的药理或遗传抑制显着增加了ROS，NF？B，以及炎性基因（ICAM-1，VCAM-1和E-纤维素），分化的3T3L1脂肪细胞和培养的原代大鼠肝细胞质。同时，在支持AMPK充当氧化剂应激的抑制剂时，我们获得了初步证据，表明通过缺血性预处理（IPC）激活AMPK有效地阻断了缺氧/重氧触发的氧化剂应激。 AMPK减少氧化剂应激的最终证据是IPC未能改变AMPK 11敲除（KO）小鼠中氧化应激和内皮功能的标记。一致地，我们发现，与野生类型相比，从AMPK 11或12 KO小鼠中分离出的主动脉表现出内皮弛豫受损，以及O2.-和Onoo-的检测增加。同样，在AMPK12 KO小鼠中，NADPH氧化酶亚基水平更高，包括GP91Phox（NOX2），NOX-4，P22Phox，P47Phox和P67phox，NAD（P）H氧化酶活性的增加。重要的是，Apocynin是一种有效的NAD（P）H氧化酶抑制剂，它恢复了AMPK 12 KO小鼠中乙酰胆碱诱导的内皮依赖性松弛，进一步表明NAD（P）H氧化酶在功能上具有活性，并且负责AMPK 12KO小鼠的内皮功能受损。最后，在不改变血浆脂质（胆固醇和甘油三酸酯）的情况下，从Apo-E/AMPK11或AMPK/AMPK/AMPK 12双KO小鼠中分离出的主动脉表现出增加的氧化应激标志物，增加的动脉粥样硬化病变的检测增加，而与这些脂肪粘附分子的表达相比，与这些APO相比，动脉粥样硬化病变增加了。该应用的目的是建立（a）AMPK通过对AMP水平的较小变化做出反应的能力，可能是细胞的近端“氧化应激传感器”； （b）AMPK激活可能会触发生理反应，以抑制产生氧化剂（调节剂）和或增加抗氧化剂防御系统的过程； （c）通过减少氧化应激，AMPK保持血管细胞中的非血管生成，非炎症和动脉粥样硬化的表型。公共卫生相关性：该提案的基本前提是AMPK激活可以保护细胞和整个生物体免受心血管危险因素（例如尼古丁）的不利影响，例如降低氧化剂应激的运动事件。为了清楚起见并集中在当前的应用中，我们将尼古丁用作与心血管疾病有关的病理刺激。由于越来越多的证据表明氧化应激与心血管危险因素的血管作用有关，包括高胆固醇血症，糖尿病和高血压，因此，该提案的重要性超出了尼古丁的范围，将适用于其他心血管疾病。当前的申请解决了生物学和医学中的一个基本问题，即如何在健康和疾病中检测和调节氧化应激源。因此，该应用的完成可能会为AMPK在压力反应中的作用增加一个全新的维度，并在氧化应激，能量代谢和心血管生物学之间提供界面。拟议研究的完成将提供新的见解，以了解AMPK是否是吸烟和常见疾病治疗的潜在靶标，包括衰老，肥胖，糖尿病，高血压和动脉粥样硬化。