The Role of Caspase-8 in Alzheimer's Disease

Caspase-8 在阿尔茨海默病中的作用

• 批准号: 6348617
• 负责人: TROY T ROHN
• 金额: $ 12.25万
• 依托单位: BOISE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6348617
• 关键词: Alzheimer's disease; CD95 molecule; active sites; antibody; antigen antibody reaction; apoptosis; biotechnology; brain; cell growth regulation; cell line; chemical cleavage; clone cells; cysteine endopeptidases; enzyme activity; enzyme structure; human tissue; immunocytochemistry; immunologic substance development /preparation; neuroblastoma; neurons; spectrin; tissue /cell culture; tumor necrosis factor alpha; western blottings; zymogens

DESCRIPTION (Adapted from applicant's abstract): A prominent feature of Alzheimer's disease (AD) is the loss of neurons by apoptotic cell death. Apoptosis is characterized by plasma membrane blebbing, nuclear condensation, and DNA fragmentation and is initiated by the activation of caspases, a family of aspartate proteases. The initiation of apoptosis involves the sequential activation of pro-caspases to their active form by proteolysis. Two key members of this family are caspase-8, the most apical member of the caspases, and caspase-3 that is commonly referred to as the executioner member of this family. Because caspases are specific, cleaving after aspartic residues, this generates caspase cleavage products (CCPs) that are antigenically distinct and therefore, represent desirable targets for cleavage site-directed antibodies. Using this approach, we designed an antibody to CCPs of fodrin, a neuronal cytoskeleton protein, and showed widespread accumulation of these products in Alzheimer's disease. Thus, while no staining was observed in control cases, labeling of neurons was observed in the hippocampus and entorhinal cortex of all AD cases, which increased as a function of disease progression. This study along with others has demonstrated a prominent role for the activation of apoptotic mechanisms in neurons of the AD brain. Presently, there are two major pathways of apoptosis: the death receptor pathway in which caspase-8 plays a critical initiator role and the mitochondrial pathway involving oxidative stress and activation of caspase-9. Induction of cell death via the Fas/TNFR super family of death receptors is mediated by adapter proteins (e.g., Fas-associated death domain, FADD) and initiation caspases (e.g., caspase-8). In the present application we test the role of the death receptor pathway and caspase-8 in Alzheimer's disease. To examine the role of caspase-8 in Alzheimer's disease we will propose to 1) develop cleavage site-directed antibodies against the active fragments of caspase-8; 2) characterize these antibodies using model systems of apoptosis; 3) use this antibody together with the fodrin CCP antibody to determine the role of caspase-8 in mediating the activation of caspase-3 in neurons of the AD brain. Elucidation of the exact apoptotic pathway involved in the eventual activation of caspase-3 will lead to the identification of newer, more specific targets for pharmacological intervention that may be useful for the treatment of Alzheimer's disease.

描述（改编自申请人的摘要）：阿尔茨海默氏病（AD）的突出特征是凋亡细胞死亡丧失神经元。 凋亡的特征是质膜吹气，核凝结， 和DNA碎片化，并由胱天蛋白酶的激活引发 天冬氨酸蛋白酶。凋亡的开始涉及顺序 通过蛋白水解激活促叶碱的活性形式。两个主要成员 这个家庭的是caspase-8，是caspase中最重要的成员， caspase-3通常称为执行者成员 家庭。因为胱天蛋白酶是特定的，在天冬氨酸残基后切割，所以 生成抗原不同且 因此，代表切割位置定向抗体的理想靶标。 使用这种方法，我们设计了一种抗Fodrin CCP的抗体，神经元 细胞骨架蛋白，并显示这些产品的广泛积累 阿尔茨海默氏病。因此，尽管在对照病例中未观察到染色，但 在海马和内嗅皮层中观察到神经元的标记 所有的AD病例都随着疾病进展的函数而增加。这项研究 与他人一起表现出了激活的重要作用 AD大脑神经元中的凋亡机制。目前，有两个主要 凋亡的途径：caspase-8扮演的死亡受体途径 关键的引发剂角色和涉及氧化的线粒体途径 caspase-9的压力和激活。通过FAS/TNFR诱导细胞死亡 超级死亡受体家族是由衔接蛋白介导的（例如， FAS相关的死亡领域，FADD）和起始caspase（例如caspase-8）。 在本应用中，我们测试了死亡受体途径的作用， 阿尔茨海默氏病的caspase-8。检查caspase-8在 阿尔茨海默氏病我们将提议1）开发裂解位置 针对caspase-8的活性片段的抗体； 2）表征这些 使用凋亡模型系统的抗体； 3）将此抗体与 Fodrin CCP抗体确定caspase-8在介导 AD脑神经元中caspase-3的激活。阐明 caspase-3最终激活涉及的凋亡途径将导致 鉴定药理学新的，更具体的目标 可能对治疗阿尔茨海默氏病有用的干预措施。