Isolating small-molecule enhancers of HtrA1, an alpha-synuclein disaggregase

分离 HtrA1（一种 α-突触核蛋白解聚酶）的小分子增强子

• 批准号: 9374303
• 负责人: James Shorter
• 金额: $ 20.02万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9374303
• 关键词: Adverse effects; Alzheimer' s Disease; Amyloid; Amyloid Fibrils; Amyloid beta-Protein; Area; Binding; Biological Assay; Collection; Cytoplasm; Cytoplasmic Inclusion; Data; Defect; Disease; Enhancers; Extracellular Space; FDA approved; Frontotemporal Dementia; Homo; Human; In Vitro; Lead; Lewy Bodies; Libraries; Measures; Methods; Mitochondria; Modeling; Molecular Chaperones; Movement Disorders; Nature; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Parkinson Disease; Pathologic; Patients; Peptide Hydrolases; Pharmaceutical Preparations; Protease Domain; Protein Isoforms; Proteins; Recombinants; Rewards; Rodent Model; Series; Serine Protease; Structure; Therapeutic; Toxic effect; United States National Institutes of Health; Variant; Yeasts; alpha synuclein; alternative treatment; conformer; dopaminergic neuron; effective therapy; misfolded protein; novel; palliative; presynaptic; prevent; protein misfolding; proteostasis; protoporphyrin IX; reconstitution; small molecule; small molecule therapeutics; synuclein; tau Proteins; treatment strategy

Project summary In Parkinson's Disease (PD), the proteostasis network fails to counter the misfolding of -synuclein (-syn). - Syn forms soluble toxic oligomers and self-templating amyloid fibrils that can initiate and propagate disease de novo. -Syn fibrils cluster into large cytoplasmic inclusions termed Lewy Bodies, a pathological hallmark of PD. Human molecular chaperones, Hsp110, Hsp70, and Hsp40 can disaggregate -syn fibrils and reduce their toxicity. These findings together with our advances with Hsp104 and potentiated variants suggest that -syn oligomers and fibrils are not intractable but can be rapidly disassembled into non-toxic forms. More recently, a second human protein disaggregase, HtrA1, has been discovered that disassembles and degrades tau and amyloid-beta fibrils. HtrA1 is a chaperone and homo-oligomeric PDZ serine protease found in the cytoplasm and extracellular space, which selectively degrades misfolded substrates while leaving folded substrates alone. Our unpublished data suggest that HtrA1 rescues -syn toxicity in yeast, and, disassembles and degrades - syn fibrils in vitro. We hypothesize that small-molecule enhancers of HtrA1 disaggregase activity could stimulate the elimination of deleterious -syn accumulations in the degenerating neurons of PD patients. Thus, we propose that the unanticipated protein disaggregase activity of HtrA1 represents a promising, novel PD- relevant target. We hypothesize that enhancing the activity of HtrA1 disaggregase activity with specific small molecules will enable dissolution and degradation of toxic oligomeric and amyloid forms of - syn, and confer therapeutic benefits in PD. Thus, we will pursue two specific aims: (1) Isolate small molecules that enhance the -syn disaggregase activity of HtrA1; and (2) Assess the ability of small-molecule enhancers of HtrA1 disaggregase activity to rescue -syn aggregation and toxicity in mammalian primary neuron models of PD. By the end of this project, there will be a clear “go/no go” decision for moving a small- molecule enhancer of HtrA1 into rodent models and ultimately PD patients. Small-molecule stimulation of HtrA1 disaggregase activity could eliminate deleterious -syn misfolding in degenerating dopaminergic neurons and provide a game-changing solution for PD. Importantly, small-molecule enhancers of HtrA1 disaggregase activity may also have important applications in other neurodegenerative disorders caused by deleterious protein misfolding, including Alzheimer's disease and frontotemporal dementia.

项目概要 在帕金森病 (PD) 中，蛋白质稳态网络无法对抗 α-突触核蛋白 (α-syn) 的错误折叠。 - Syn 形成可溶性有毒低聚物和自模板淀粉样原纤维，可以引发和传播疾病 新的。 α-Syn 原纤维聚集成称为路易体的大细胞质内含物，这是 PD 的病理标志。 人类分子伴侣 Hsp110、Hsp70 和 Hsp40 可以解聚 α-syn 原纤维并减少其 毒性。这些发现与我们在 Hsp104 和增强变体方面取得的进展一起表明 α-syn 低聚物和原纤维并不难处理，但可以快速分解成无毒形式。最近，一个 第二种人类蛋白质解聚酶 HtrA1 被发现可以分解和降解 tau 蛋白 淀粉样蛋白-β原纤维。 HtrA1 是一种分子伴侣和同源寡聚 PDZ 丝氨酸蛋白酶，存在于细胞质中 和细胞外空间，选择性地降解错误折叠的底物，同时保留折叠的底物。 我们未发表的数据表明，HtrA1 可以解救酵母中的 α-syn 毒性，并且分解和降解 α- 体外合成原纤维。我们假设 HtrA1 解聚酶活性的小分子增强剂可以 刺激消除 PD 患者退化神经元中有害的 α-syn 积累。因此， 我们认为 HtrA1 的意想不到的蛋白质解聚酶活性代表了一种有前途的新型 PD- 相关目标。我们假设通过特异性增强 HtrA1 解聚酶活性 小分子能够溶解和降解有毒的寡聚体和淀粉样形式的α- syn，并赋予 PD 治疗益处。因此，我们将追求两个具体目标：（1）隔离小 增强 HtrA1 α-syn 解聚酶活性的分子； (2)评估小分子的能力 HtrA1 解聚酶活性的增强剂可拯救哺乳动物原代细胞中的 α-syn 聚集和毒性 PD的神经元模型。到该项目结束时，将有一个明确的“继续/不继续”决定来移动小型项目 HtrA1 分子增强剂进入啮齿动物模型并最终进入 PD 患者。小分子刺激 HtrA1解聚酶活性可以消除退化多巴胺能中有害的α-syn错误折叠 神经元，并为 PD 提供改变游戏规则的解决方案。重要的是，HtrA1 的小分子增强剂 解聚集酶活性也可能在由以下原因引起的其他神经退行性疾病中具有重要应用： 有害的蛋白质错误折叠，包括阿尔茨海默病和额颞叶痴呆。