Autoimmune Mechanisms of Diabetic Neuropathy

糖尿病神经病变的自身免疫机制

• 批准号: 7919084
• 负责人: JOHN W WILEY
• 金额: $ 10万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7919084
• 关键词: 1-Phosphatidylinositol 3-Kinase; Adenosine Triphosphate; Age; Agonist; Animal Model; Animals; Apoptosis; Apoptotic; Autoantibodies; Autoimmune Process; Autoimmunity; Autophagocytosis; Autophagosome; Binding; Binding Proteins; Biological Markers; Budgets; CD95 Antigens; Cardiovascular system; Caspase; Cell membrane; Cells; Cellular Stress; Cessation of life; Complement; Data; Death Domain; Development; Diabetes Mellitus; Diabetic Neuropathies; Diagnosis; Diet; Disease; Enrollment; Event; Family; Fatty acid glycerol esters; Female; Functional disorder; Gender; Gene Silencing; Hour; Human; Immunoglobulins; In Situ; In Vitro; Injury; Lead; Link; Longitudinal Studies; Malignant Neoplasms; Mediating; Methods; Mitochondria; Modeling; Monitor; Myenteric Plexus; Nervous system structure; Neuroblastoma; Neuronal Dysfunction; Neuronal Injury; Neurons; Neuropathy; Nodose Ganglion; Non-Insulin-Dependent Diabetes Mellitus; Organelles; Oxidative Stress; Pathway interactions; Patients; Pattern; Peripheral; Peripheral Nervous System Diseases; Play; Process; Proteins; Public Health; Rattus; Reporting; Research; Research Personnel; Role; Sensory; Serum; Spinal Ganglia; Streptozocin; TNFRSF6 gene; Time; autonomic neuropathy; base; cohort; diabetic; diabetic patient; diabetic rat; exhaust; inhibitor/antagonist; injured; insight; member; mitochondrial dysfunction; mitochondrial permeability transition pore; non-diabetic; novel; programs; receptor; release factor; research study; response

The pathophysiology of diabetic neuropathy is poorly understood. We reported previously that sera from patients with type 2 diabetes mellitus with neuropathy induced programmed cell death (PCD) in cultured human neuroblastoma cells via an autoantibody-mediated pathway involving activation of caspase- dependent apoptosis. Recent studies support that a caspase-independent pathway can also contribute to PCD. This process may involve activation of autophagy, a pathway that sequesters proteins and organelles in autophagosomes in response to cellular stress. We propose the novel hypothesis that autoantibodies present in the sera of type 2 diabetic patients with neuropathy sequentially activate autophagy, caspase- dependent and -independent PCD in neurons via a Fas-dependent pathway. Fas (CD95) is a member of the cell membrane-bound death receptor family. Our preliminary data support the hypothesis that agonist autoantibodies bind and activate the Fas receptor. We will monitor the development of autoantibody(-ies) and correlate their presence with established markers of autonomic and peripheral neuropathy in an early and later cohort of patients with type 2 diabetes mellitus. We will dissect the pathway(s) that induce autophagy and PCD. We propose that autophagy is an early cytoprotective response to remove injured mitochondria that progresses sequentially to caspase-dependent and -independent PCD with decrease in ATP levels. We hypothesize that autoantibody-induction of autophagy will involve incorporation of LC3n, a specific marker for autophagosomes, and activation of PI-3 kinase (class III). Cultured SH-SY5Y (human neuroblastoma cells) will be exposed to complement-inactivated sera obtained from: 1. type 2 diabetic patients with documented diabetic neuropathy, 2. Age- and gender- matched type 2 diabetic patients without evidence of neuropathy and 3. Healthy, age- and gender-matched controls. Parallel animal studies will be performed examining whether autophagy is activated in situ in primary neurons (nodose ganglia, dorsal root ganglia and myenteric plexus) obtained from the female Zucker Diabetic Fatty rat, an inducible model of type 2 diabetes and the streptozotocin-induced diabetic rat, a well validated model of diabetic neuropathy. We will also assess whether sera from diabetic rats with neuropathy induce autophagy and caspase-dependent and/or -independent PCD in cultured rat nodose ganglia, DRG and myenteric neurons compared to sera from diabetic rats without neuropathy and lean, non-diabetic controls, and examine the time-course for these events. We hypothesize that mitochondrial dysfunction and decreased levels of ATP will play a pivotal role in sequential activation of caspase-dependent and -independent PCD. Relevance to public health: These studies will lead to novel insights regarding the mechanistic basis of autoimmunity, autophagy and programmed cell death in the pathophysiology of diabetic neuropathy. .

糖尿病性神经病变的病理生理机制知之甚少。我们以前报道过， 2型糖尿病合并神经病变的患者在培养的 人神经母细胞瘤细胞通过自身抗体介导的途径，涉及激活半胱天冬酶- 依赖性凋亡最近的研究支持，半胱天冬酶非依赖性途径也可以有助于 PCD。这一过程可能涉及自噬的激活，自噬是一种隔离蛋白质和细胞器的途径 在细胞应激反应中的作用。我们提出了一个新的假设， 存在于具有神经病变的2型糖尿病患者的血清中， 依赖性和非依赖性PCD的神经元通过Fas依赖性途径。Fas（CD 95）是一个重要的免疫调节因子。 细胞膜结合死亡受体家族。我们的初步数据支持激动剂 自身抗体结合并激活Fas受体。我们将监测自身抗体的发展 并将它们的存在与早期自主神经和周围神经病变的既定标志物相关联。 以及2型糖尿病患者的后一队列。我们将剖析诱导的途径 自噬和PCD。我们认为自噬是一种早期的细胞保护反应， 线粒体依次进展为半胱天冬酶依赖性和非依赖性PCD， ATP水平。我们推测，自体抗体诱导的自噬将涉及LC 3 n的掺入， 自噬体的特异性标志物和PI-3激酶（III类）的活化。培养的SH-SY 5 Y（人 神经母细胞瘤细胞）将暴露于从以下获得的补体灭活血清：1. 2型糖尿病 有糖尿病神经病变记录的患者，2.年龄和性别匹配的2型糖尿病患者， 神经病变的证据和3.健康、年龄和性别匹配的对照组。平行动物研究将 进行检查是否在原代神经元（结状神经节，背根）中原位激活自噬 神经节和肌间神经丛），该模型是从雌性Zucker糖尿病肥胖大鼠获得的， 2型糖尿病和链脲佐菌素诱导的糖尿病大鼠，糖尿病神经病变的良好验证的模型。我们将 还评估了来自具有神经病变的糖尿病大鼠的血清是否诱导自噬和半胱天冬酶依赖性 与血清相比，在培养的大鼠结状神经节、DRG和肌间神经元中， 从糖尿病大鼠无神经病变和瘦，非糖尿病对照，并检查这些时间过程 事件我们推测线粒体功能障碍和ATP水平降低将在 在caspase依赖性和非依赖性PCD的顺序激活中。与公共卫生的相关性：这些 研究将导致关于自身免疫，自噬和 糖尿病神经病变病理生理学中的程序性细胞死亡。 .