Division for Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA.
Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland, USA.
Environ Health Perspect. 2021 Apr;129(4):47008. doi: 10.1289/EHP6993. Epub 2021 Apr 12.
Inhibition of acetylcholinesterase (AChE), a biomarker of organophosphorous and carbamate exposure in environmental and occupational human health, has been commonly used to identify potential safety liabilities. So far, many environmental chemicals, including drug candidates, food additives, and industrial chemicals, have not been thoroughly evaluated for their inhibitory effects on AChE activity. AChE inhibitors can have therapeutic applications (e.g., tacrine and donepezil) or neurotoxic consequences (e.g., insecticides and nerve agents).
The objective of the current study was to identify environmental chemicals that inhibit AChE activity using and models.
To identify AChE inhibitors rapidly and efficiently, we have screened the Toxicology in the 21st Century (Tox21) 10K compound library in a quantitative high-throughput screening (qHTS) platform by using the homogenous cell-based AChE inhibition assay and enzyme-based AChE inhibition assays (with or without microsomes). AChE inhibitors identified from the primary screening were further tested in monolayer or spheroid formed by SH-SY5Y and neural stem cell models. The inhibition and binding modes of these identified compounds were studied with time-dependent enzyme-based AChE inhibition assay and molecular docking, respectively.
A group of known AChE inhibitors, such as donepezil, ambenonium dichloride, and tacrine hydrochloride, as well as many previously unreported AChE inhibitors, such as chelerythrine chloride and cilostazol, were identified in this study. Many of these compounds, such as pyrazophos, phosalone, and triazophos, needed metabolic activation. This study identified both reversible (e.g., donepezil and tacrine) and irreversible inhibitors (e.g., chlorpyrifos and bromophos-ethyl). Molecular docking analyses were performed to explain the relative inhibitory potency of selected compounds.
Our tiered qHTS approach allowed us to generate a robust and reliable data set to evaluate large sets of environmental compounds for their AChE inhibitory activity. https://doi.org/10.1289/EHP6993.
乙酰胆碱酯酶(AChE)的抑制作用是环境和职业人群中有机磷和氨基甲酸酯暴露的生物标志物,常用于识别潜在的安全风险。迄今为止,许多环境化学物质,包括候选药物、食品添加剂和工业化学品,尚未对其对 AChE 活性的抑制作用进行彻底评估。AChE 抑制剂具有治疗应用(如他克林和多奈哌齐)或神经毒性后果(如杀虫剂和神经毒剂)。
本研究的目的是使用 和 模型来鉴定抑制 AChE 活性的环境化学物质。
为了快速有效地鉴定 AChE 抑制剂,我们使用基于细胞的 AChE 抑制测定和基于酶的 AChE 抑制测定(有或没有微粒体),在高通量筛选(HTS)平台中筛选了 21 世纪毒理学(Tox21)10K 化合物库。从初步筛选中鉴定出的 AChE 抑制剂在单层或由 SH-SY5Y 和神经干细胞模型形成的球体中进一步进行测试。通过时间依赖性基于酶的 AChE 抑制测定和分子对接分别研究这些鉴定化合物的抑制和结合模式。
本研究鉴定出一组已知的 AChE 抑制剂,如多奈哌齐、氨甲酰氯和盐酸他克林,以及许多以前未报道的 AChE 抑制剂,如氯化白屈菜碱和西洛他唑。这些化合物中的许多,如吡唑磷、硫丹和三唑磷,需要代谢激活。本研究鉴定了可逆抑制剂(如多奈哌齐和他克林)和不可逆抑制剂(如毒死蜱和溴磷-乙基)。进行了分子对接分析以解释所选化合物的相对抑制效力。
我们的分层 qHTS 方法使我们能够生成一个稳健可靠的数据集,用于评估大量环境化合物对 AChE 抑制活性的影响。https://doi.org/10.1289/EHP6993.