Synthesis of novel 4-methylthiocoumarin and comparison with conventional coumarin derivative as a multi-target-directed ligand in Alzheimer’s disease
作者:Shivani Kumar、Yogesh Kumar Tyagi、Manoj Kumar、Suresh Kumar
DOI:10.1007/s13205-020-02481-1
日期:2020.12
Alzheimer’s disease (AD) is a multifactorial disorder characterized by cognitive deficit and memory loss. The pathological feature of the disease involves β-amyloid senile plaques, reduced levels of acetylcholine neurotransmitter, oxidative stress and neurofibrillary tangles formation within the brain of AD patients. The present study aims to screen the inhibitory activity of newly synthesized and existing novel 4-methylthiocoumarin derivative against acetylcholinesterase, butyrylcholinesterase, BACE1, β-amyloid aggregation and oxidative stress involved in the AD pathogenesis. The in vitro assays used in this study were Ellman’s assay, FRET assays, Thioflavin T, transmission electron microscopy, circular dichroism, FRAP, and TEAC. Molecular docking and dynamics studies were performed to correlate the results. C3 and C7 (thiocoumarin derivatives) were found to be the most potent inhibitors of acetylcholinesterase (IC50-5.63 µM) and butyrylcholinesterase (IC50-3.40 µM) using Ellman’s assays. Enzyme kinetic studies showed that C3 and C7 compounds followed by the mixed mode of inhibition using LB plot. C3 also moderately inhibited the BACE1 using FRET assay. C3 inhibited the fibrillization of β-amyloid peptides in a concentration-dependent manner as observed by Thioflavin T, TEM studies and Circular dichroism data. Molecular modeling studies were performed to understand the probable mode of binding of C3 and C7 in the binding pocket of acetylcholinesterase, butyrylcholinesterase, BACE1 and amyloid β peptides. This indicates the important role of hydrophobic interactions between C3 and acetylcholinesterase. C3 also exhibited significant antioxidant potential by FRAP and TEAC assays. Hence, C3 might serve as a promising lead for developing novel multi target-directed ligand for the treatment of AD.
阿尔茨海默病(AD)是一种多因素疾病,以认知缺陷和记忆丧失为特征。该病的病理特征包括β-淀粉样蛋白老年斑、乙酰胆碱神经递质水平降低、氧化应激和神经纤维缠结。本研究旨在筛选新合成的和现有的新型 4-甲基硫代香豆素衍生物对乙酰胆碱酯酶、丁酰胆碱酯酶、BACE1、β-淀粉样蛋白聚集和氧化应激的抑制活性。本研究采用的体外检测方法包括埃尔曼试验、FRET 试验、硫黄素 T、透射电子显微镜、圆二色法、FRAP 和 TEAC。还进行了分子对接和动力学研究,以对结果进行关联。通过埃尔曼试验发现,C3 和 C7(硫代香豆素衍生物)是乙酰胆碱酯酶(IC50-5.63 µM)和丁酰胆碱酯酶(IC50-3.40 µM)最有效的抑制剂。酶动力学研究表明,C3 和 C7 复合物采用混合抑制模式,使用 LB 图。利用 FRET 分析法,C3 还能适度抑制 BACE1。根据硫黄素 T、TEM 研究和环二色性数据的观察,C3 以浓度依赖性的方式抑制了 β 淀粉样肽的纤维化。为了解 C3 和 C7 在乙酰胆碱酯酶、丁酰胆碱酯酶、BACE1 和淀粉样β肽结合袋中的可能结合模式,进行了分子建模研究。这表明 C3 与乙酰胆碱酯酶之间的疏水相互作用发挥了重要作用。通过 FRAP 和 TEAC 试验,C3 还表现出了明显的抗氧化潜力。因此,C3有可能成为开发治疗AD的新型多靶点配体的线索。