Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States.
Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States.
ACS Chem Neurosci. 2023 Nov 1;14(21):3913-3927. doi: 10.1021/acschemneuro.3c00464. Epub 2023 Oct 11.
Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder underlying dementia in the geriatric population. AD manifests by two pathological hallmarks: extracellular amyloid-β (Aβ) peptide-containing senile plaques and intraneuronal neurofibrillary tangles comprised of aggregated hyperphosphorylated tau protein (p-tau). However, more than half of AD cases also display the presence of aggregated α-synuclein (α-syn)-containing Lewy bodies. Conversely, Lewy bodies disorders have been reported to have concomitant Aβ plaques and neurofibrillary tangles. Our drug discovery program focuses on the synthesis of multitarget-directed ligands to abrogate aberrant α-syn, tau (2N4R), and p-tau (1N4R) aggregation and to slow the progression of AD and related dementias. To this end, we synthesized 11 compounds with a triazine-linker and evaluated their effectiveness in reducing α-syn, tau isoform 2N4R, and p-tau isoform 1N4R aggregation. We utilized biophysical methods such as thioflavin T (ThT) fluorescence assays, transmission electron microscopy (TEM), photoinduced cross-linking of unmodified proteins (PICUP), and M17D intracellular inclusion cell-based assays to evaluate the antiaggregation properties and cellular protection of our best compounds. We also performed disaggregation assays with isolated Aβ-plaques from human AD brains. Our results demonstrated that compound was effective in reducing both oligomerization and fibril formation of α-syn and tau isoform 2N4R in a dose-dependent manner via ThT and PICUP assays. Compound was also effective at reducing the formation of recombinant α-syn, tau 2N4R, and p-tau 1N4R fibrils by TEM. Compound reduced the development of α-syn inclusions in M17D neuroblastoma cells and stopped the seeding of tau P301S using biosensor cells. Disaggregation experiments showed smaller Aβ-plaques and less paired helical filaments with compound . Compound may provide molecular scaffolds for further optimization and preclinical studies for neurodegenerative proteinopathies.
阿尔茨海默病（AD）是导致老年人群痴呆的最常见神经退行性疾病。AD 表现为两个病理特征：细胞外含有淀粉样β（Aβ）肽的老年斑和由聚集的过度磷酸化 tau 蛋白（p-tau）组成的神经元内神经原纤维缠结。然而，超过一半的 AD 病例还表现出含有聚集的α-突触核蛋白（α-syn）的路易体。相反，已经报道路易体疾病伴有 Aβ 斑块和神经原纤维缠结。我们的药物发现计划专注于合成多靶点定向配体，以消除异常的α-syn、tau（2N4R）和 p-tau（1N4R）聚集，并减缓 AD 和相关痴呆的进展。为此，我们合成了 11 种带有三嗪连接体的化合物，并评估了它们降低α-syn、tau 同工型 2N4R 和 p-tau 同工型 1N4R 聚集的效果。我们利用生物物理方法，如硫黄素 T（ThT）荧光测定法、透射电子显微镜（TEM）、未修饰蛋白的光诱导交联（PICUP）和 M17D 细胞内包涵体细胞测定法，来评估我们最佳化合物的抗聚集特性和细胞保护作用。我们还用人 AD 大脑中的分离 Aβ 斑块进行了解聚实验。我们的结果表明，化合物在 ThT 和 PICUP 测定中通过剂量依赖性方式有效降低了α-syn 和 tau 同工型 2N4R 的寡聚化和纤维形成。化合物也能有效减少重组α-syn、tau 2N4R 和 p-tau 1N4R 纤维的形成，通过 TEM。化合物减少了 M17D 神经母细胞瘤细胞中α-syn 包涵体的形成，并使用生物传感器细胞阻止了 tau P301S 的播种。解聚实验表明，与化合物相比，Aβ 斑块更小，双螺旋丝更少。化合物可能为神经退行性蛋白病的进一步优化和临床前研究提供分子支架。
