Does Necroptosis Play a Role in Inflammation and Aging

坏死性凋亡在炎症和衰老中起作用吗

• 批准号: 10166597
• 负责人: ARLAN G. RICHARDSON
• 金额: --
• 依托单位: OKLAHOMA CITY VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10166597
• 关键词: Affect; Age; Age-Years; Aging; Alzheimer' s Disease; Alzheimer' s disease model; Amyotrophic Lateral Sclerosis; Animals; Apoptosis; Atherosclerosis; Attenuated; Autopsy; Binding; Brain; Cardiovascular Diseases; Cell Death; Cell membrane; Cells; Chronic; Cognition; Cytolysis; Data; Disease; Dwarfism; Elderly; FRAP1 gene; Feedback; Generations; Hand Strength; Human; Immune; Individual; Inflammaging; Inflammasome; Inflammation; Intervention; Knock-out; Knockout Mice; Link; Longevity; MAP Kinase Gene; Malignant Neoplasms; Measures; Mediating; Mitochondrial DNA; Molecular; Morbidity - disease rate; Mus; Necrosis; Neurodegenerative Disorders; Non-Insulin-Dependent Diabetes Mellitus; Oxidative Stress; Pathology; Pathway interactions; Pattern; Performance; Pharmacology; Phosphorylation; Phosphotransferases; Play; Production; Protein Kinase; Proteins; RIPK1 gene; RIPK3 gene; Research; Risk Factors; Role; Signal Transduction; Stimulus; TNF gene; Testing; Tissues; Transcription Factor AP-1; United States Department of Veterans Affairs; Up-Regulation; Veterans; Wild Type Mouse; age effect; age related; anti aging; base; cell type; cytokine; demographics; dietary restriction; frailty; healthspan; improved; inhibitor/antagonist; insulin sensitivity; military veteran; mortality; mouse model; neuron loss; novel; prevent

Chronic, low-grade inflammation (inflammaging) is a hallmark of aging and is a major risk factor for both morbidity and mortality in the elderly humans. In addition, inflammation is a major risk factor for a variety of age-related diseases, e.g. type 2 diabetes, cardiovascular disease, cancer, neurodegenerative diseases, frailty, etc. Despite the link between inflammation, aging, and age-associated diseases, we do not know the molecular mechanism(s)/pathway(s) responsible for the chronic, low-grade inflammation seen in old animals and whether the increase in chronic inflammation is a causative factor in aging and age-related diseases. Necroptosis is a recently identified pathway of programmed necrosis that induces cell death through the lysis of cells, resulting in the release of damage-associated molecular patterns (DAMPs) from the dead cells. DAMPs are potent inducers of inflammation, and circulating DAMPs have been shown to increase with age in humans and to be strongly correlated to the level of inflammation in the individual. We hypothesize that necroptosis plays a role in chronic, low-grade inflammation, which occurs with age, and preventing necroptosis will attenuate inflammation, leading to increased lifespan, improved healthspan, and reduced age-related pathology. We will use genetically modified mouse models and a pharmacological intervention to block/reduce apoptosis by targeting the receptor-interacting protein kinases (RIPK) 1 or 2 and mixed lineage kinase domain like (MLKL) protein, which are involved in the initiation of necroptosis. Aim1. Determine the role of necroptosis in chronic inflammation that occurs with age and the types of cells undergoing necroptosis. We will determine the effect of reducing necroptosis either genetically (using Ripk3+/-, Ripk3-/-, Mlkl+/-, and Mlkl-/- mice) or pharmacologically (treating with necrostatin-1s, a RIPK1 inhibitor) on inflammation. We will also identify the cell type(s) that undergo necroptosis in selected tissues of old mice. Based on our hypothesis, we predict that those tissues showing an up-regulation in necroptosis with age will show an increase in production of proinflammatory cytokines and reducing/blocking necroptosis will decrease inflammation in these tissues as well as circulating levels of proinflammatory cytokines. Aim2. Identify the pathways that increase necroptosis with age and determine the mechanism(s) that mediates the age-related increase in inflammation arising from necroptosis. TNFα, oxidative stress, and mTOR signaling have been proposed to initiate necroptosis, and these pathways increase with age. In Aim 2, we determine the role of these pathways play in the age-related increase in necroptosis using specific inhibitors to each of the pathways. DAMPs released by necroptotic cells induce inflammation through activation of three pathways: the IKK-NF-κB, MAPK-AP1 and inflammasome pathways. In Aim 2, we will also assess the effect of age on the activation of these pathways in various tissues of WT mice and determine which of the pathways are reduced when necroptosis is reduced/blocked in Ripk3 and Mlkl knockout mice or by necrostatin-1s treatment. Aim3. Determine the role of necroptosis in aging. In Aim 3, two groups of mice in which necroptosis has been blocked/reduced will be compared to wildtype mice. Mouse models (e.g., Ripk3 and/or Mlkl knockout mice) will be used that we find block inflammaging in Aim 1. The lifespan, healthspan (e.g., activity, rotarod performance, grip strength, insulin sensitivity, cognition, etc.), and age-associated pathology of these mice will be compared to WT mice. Based on our hypothesis, we predict that reducing/blocking necroptosis will retard aging as shown by improved healthspan, reduced pathology, and increased lifespan. These data would provide the first direct evidence that necroptosis induced inflammation is directly involved in aging and that chronic, low-grade inflammation plays a role in aging and the increase in pathology and age-related diseases.

慢性低级炎症（炎症）是衰老的标志，是两者的主要危险因素 老年人的发病率和死亡率。此外，炎症是各种各样的主要危险因素 与年龄有关的疾病，例如2型糖尿病，心血管疾病，癌症，神经退行性疾病， 尽管炎症，衰老和与年龄相关的疾病之间有联系，但我们不知道 分子机制/途径，负责老动物中慢性低级注射 以及慢性炎症的增加是否是衰老和与年龄有关的疾病的严重因素。 坏死性是最近确定的编程坏死途径，可通过歌词诱导细胞死亡 细胞，导致死细胞释放与损伤相关的分子模式（潮湿）。 潮湿是炎症的潜在诱导者 人类并与个体的感染水平密切相关。我们假设这一点 坏死作用在慢性低度炎症中起作用，随着年龄的增长而发生 坏死性会减弱感染，导致寿命增加，改善健康状态，并 减少与年龄有关的病理。我们将使用一般修改的鼠标模型和药品 干预措施通过靶向接收器相互作用蛋白激酶（RIPK）1或2，以阻断/减少凋亡 混合谱系激酶结构域（例如（MLKL）蛋白），与坏死性的倡议有关。 AIM1。确定坏死性在慢性炎症中的作用，随着年龄的类型而发生 细胞患坏死。我们将在遗传上确定降低坏死性的影响（使用 RIPK3 +/-，RIPK3 - / - ，MLKL +/-和MLKL - / - 小鼠）或药物（用Necrostatin-1s治疗RIPK1抑制剂） 关于炎症。我们还将确定在旧小鼠选定组织中发生坏死的细胞类型。 基于我们的假设，我们预测那些随着年龄年龄的坏死性上调的组织将 显示促炎细胞因子的产生和减少/阻断坏死的增加将减少 这些组织中的炎症以及促炎细胞因子的循环水平。 AIM2。确定随着年龄的增长而增加坏死性的途径，并确定 介导了坏死作用引起的与年龄相关的炎症增加。 TNFα，氧化应激和 已经提出了MTOR信号传导来引发坏死，这些途径随着年龄的增长而增加。在AIM 2中， 我们确定这些途径在使用特定的情况下在与年龄相关的坏死性增长中的作用 对每种途径的抑制剂。坏死细胞释放的潮湿通过 激活三个途径：IKK-NF-κB，MAPK-AP1和炎性途径。在AIM 2中，我们也将 评估年龄对WT小鼠各种时机激活这些途径的影响，并确定 当RIPK3和MLKL敲除小鼠中降低/阻塞坏死性时，哪些途径降低了 通过死灵抑素1S治疗。 AIM3。确定坏死性在衰老中的作用。在AIM 3中，两组坏死病的小鼠 被阻断/减少的野生型小鼠将进行比较。鼠标模型（例如RIPK3和/或MLKL敲除 将使用鼠标），我们发现AIM 1中的障碍物的障碍。寿命，HealthSpan（例如，活动，rotarod 这些小鼠的性能，抓地力，胰岛素敏感性，认知等）以及与年龄相关的病理学 与WT小鼠进行比较。基于我们的假设，我们预测减少/阻断坏死性会降低 衰老，如改善了健康跨度，病理减少和寿命增加所示。这些数据会 提供第一个直接证据，表明坏死性诱导的注射直接参与衰老，并且 慢性低级炎症在衰老和病理和与年龄有关的疾病的增加中起作用。