Neuroinflammation, Protein Aggregates, ApoE4 Drug Targeting, and Autophagy Rescue

神经炎症、蛋白质聚集体、ApoE4 药物靶向和自噬拯救

• 批准号: 10768318
• 负责人: Sue Tilton Griffin
• 金额: $ 47.03万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2028-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10768318
• 关键词: Acute-Phase Proteins; Alzheimer' s Disease; Alzheimer' s neuropathogenesis; Amyloid beta-Protein; Apolipoprotein E; Astrocytes; Autophagocytosis; Binding; Brain; Brain Diseases; Brain region; Chemical Agents; Chronic; DNA; DNA Sequence; Development; Drug Targeting; Event; Exhibits; Feedback; Functional disorder; Genes; Genetic Transcription; Genotype; Glial Fibrillary Acidic Protein; Histologic; Individual; Inherited; Interleukin-1 beta; Lead; Microglia; Modification; Molecular; Motion; Neurofibrillary Tangles; Neurons; Outcome; Parents; Pathogenesis; Patients; Pharmaceutical Preparations; Phosphotransferases; Play; Prevention strategy; Production; Protein Inhibition; Proteins; Proteomics; Reporting; Repression; Role; Stress; Testing; Work; apolipoprotein E-4; brain tissue; chemical binding; cytokine; drug candidate; gain of function; hyperphosphorylated tau; neuroinflammation; novel; protein aggregation; protein protein interaction; small molecule; transcription factor

We established the pluripotent interleukin-1β (IL-1 β) cytokine as a significant player in the pathogenesis of Alzheimer’s disease as it sets in motion a self-amplifying positive-feedback cycle in which neuronal stress induces synthesis of the neuron's acute phase protein β APP and release of its fragments sAPPa and Aβ. Both these proteins activate microglia and a progressive elevation of IL-1 β, which drives chronically enhanced formation of the hallmark aggregates of AD: A β plaques and, via IL-1 β -induced synthesis and activation of specific kinases, hyperphosphorylation of tau in neurofibrillary tangles in neurons and glial fibrillary acidic protein (GFAP) in astrocytes. Interestingly, both events are dramatically enhanced in AD patients who inherit the Alzheimer gene from both parents (genotype ApoE4,4). Although these IL-1 β and ApoE genotype driven events favor negative outcomes, our progress in drug-development initiatives shows that they are amenable to treatment. Specifically, GFAP-binding chemical agents were shown to inhibit protein aggregation. Further, we discovered a novel function of the APOE£4 gene, which is a toxic gain-of- function exhibited by its protein product, ApoE4. We have demonstrated that ApoE4 competes with Transcriptional Factor EB (TFEB) for binding to the CLEAR DNA motifs, thus, hindering the transcription of three proteins crucial for lysosomal autophagy. We show this to be the case in brain tissues from AD 4,4, but not AD 3,3 patients. Now, importantly, we have identified a lead compound that binds to ApoE4 protein, obviating its interactions with CLEAR DNA and restoring the expression of three autophagy genes, that encode for production of p62, LC3B, and LAMP2 proteins. Now, we are prepared to further elucidate the role of IL-1 β in cellular pathophysiology, establishing its effects on kinases and kinase targets that manifest the modifications which drive predominant aggregate nucleation or propagation events. Our advanced molecular and histological approaches will be applied to confirm predictions of protein-protein interactions derived from proteomics approaches, particularly those involving GFAP. Moreover, these interactions can now be evaluated across brain regions and disease states to test their concordance with known AD parameters. Finally, we will elucidate the mechanisms of action of our identified novel small-molecule drugs targeted to ApoE4 in inhibiting all its pathognomonic interactions with other ApoE4 targeted DNA sequences. Successful completion of our proposed work promises a preventive strategy for foiling the known dramatic role that ApoE4 plays in Alzheimer neuropathogenesis. RELEVANCE: Successful completion of this proposed work will obviate the many pathognomonic aspects of inheritance of the Alzheimer gene (APOEE4) in the 1 in 4 individuals in the US, i.e., 80 million, who inherit one or both copies of this gene. Through the action of our specific drug candidates to inhibit the ApoE4 protein we will, therefore, restore the lysosomal autophagy necessary for efficient clearance of large aggregates, which, as we reported, is repressed in the brains of those who inherit one or both APOE4 genes.

我们确立了多能白介素1β(IL-1β)细胞因子在阿尔茨海默病发病机制中的重要作用，因为它启动了一个自我放大的正反馈循环，在这个循环中，神经元应激诱导神经元急性时相蛋白βAPP的合成及其片段SappA和Aβ的释放。这两种蛋白都激活小胶质细胞和IL-1β的进行性升高，从而推动AD标志性聚集物：A-β斑块的慢性增强形成，并通过IL-1β诱导的特定激酶的合成和激活，使神经元中神经纤维缠结中的tau和星形胶质细胞中的胶质纤维酸性蛋白过度磷酸化。有趣的是，在从父母双方遗传阿尔茨海默氏症基因(ApoE4，4)的AD患者中，这两种情况都显著增强。尽管这些IL-1β和载脂蛋白E基因驱动的事件倾向于负面结果，但我们在药物开发倡议方面的进展表明，它们是可以接受治疗的。具体地说，GFAP结合的化学试剂被证明抑制蛋白质聚集。此外，我们还发现了APOE Gb4基因的一个新功能，这是其蛋白产物ApoE4所表现出的一种有毒的功能获得。我们已经证明了ApoE4与转录因子EB(TFEB)竞争结合到透明的DNA基序，从而阻碍了对溶酶体自噬至关重要的三种蛋白质的转录。我们在AD 4，4的脑组织中显示了这种情况，但在AD 3，3的患者中没有。现在，重要的是，我们已经确定了一种与ApoE4蛋白结合的先导化合物，消除了它与透明DNA的相互作用，并恢复了三个自噬基因的表达，这三个基因编码产生p62、LC3B和LAMP2蛋白。现在，我们准备进一步阐明IL-1β在细胞病理生理学中的作用，建立它对驱动主要聚集成核或繁殖事件的修饰的激酶和激酶靶标的影响。我们先进的分子和组织学方法将被应用于确认蛋白质组学方法，特别是涉及GFAP的方法所产生的蛋白质-蛋白质相互作用的预测。此外，这些相互作用现在可以跨大脑区域和疾病状态进行评估，以测试它们与已知AD参数的一致性。最后，我们将阐明我们识别的针对ApoE4的新型小分子药物在抑制其与其他ApoE4靶向DNA序列的所有病理性相互作用方面的作用机制。我们提议的工作的成功完成有望提供一种预防策略，以挫败载脂蛋白E4在阿尔茨海默病神经发病中所起的已知戏剧性作用。 相关性：这项拟议工作的成功完成将消除阿尔茨海默氏症基因(APOEE4)遗传的许多病因学方面的问题，在美国，每4个人中就有1人，即8000万人，继承了该基因的一个或两个副本。因此，通过我们的特定候选药物抑制ApoE4蛋白的作用，我们将恢复有效清除大集合体所需的溶酶体自噬，正如我们所报道的，在那些遗传了一个或两个APOE4基因的人的大脑中，这种自噬被抑制。