Regulation of the Soluble Amyloid Precursor Protein α (sAPPα) Levels by Acetylcholinesterase and Brain-Derived Neurotrophic Factor in Lung Cancer Cell Media

In comparing two human lung cancer cells, we previously found lower levels of acetylcholinesterase (AChE) and intact amyloid-β40/42 (Aβ), and higher levels of mature brain-derived neurotrophic factor (mBDNF) in the media of H1299 cells as compared to A549 cell media. In this study, we hypothesized that the levels of soluble amyloid precursor protein α (sAPPα) are regulated by AChE and mBDNF in A549 and H1299 cell media. The levels of sAPPα were higher in the media of H1299 cells. Knockdown of AChE led to increased sAPPα and mBDNF levels and correlated with decreased levels of intact Aβ40/42 in A549 cell media. AChE and mBDNF had opposite effects on the levels of Aβ and sAPPα and were found to operate through a mechanism involving α-secretase activity. Treatment with AChE decreased sAPPα levels and simultaneously increased the levels of intact Aβ40/42 suggesting a role of the protein in shifting APP processing away from the non-amyloidogenic pathway and toward the amyloidogenic pathway, whereas treatment with mBDNF led to opposite effects on those levels. We also show that the levels of sAPPα are regulated by protein kinase C (PKC), extracellular signal-regulated kinase (ERK)1/2, phosphoinositide 3 Kinase (PI3K), but not by protein kinase A (PKA).     

涡虫神经再生与原始脑构建初探

利用石蜡切片、乙酰胆碱酯酶组织化学定位和切割再生实验方法,研究两类涡虫的神经结构,发现AChE 的神经结构在HE染色中,脑周围有许多形态不同的细胞,脑中部组织充满胶质的纤维状结构,几乎不存在典型的细胞.提出涡虫的再生能力与其生殖方式密切相关.对原始脑构建提出新看法,认为脑构建的起源,首先是形成类神经物质,然后是多功能的类神经细胞,之后形成了原始的神经网,进一步分化为神经索.为了功能上的沟通和协调,神经索前端分化、发育、膨大成神经节,同时膨大部位相互接近,发出突触互相联系,协调身体左右边活动、捕食、感觉和反应,形成所谓的“脑”,即脑神经节.     

Selected 1,3-Benzodioxine-Containing Chalcones as Multipotent Oxidase and Acetylcholinesterase Inhibitors

Chalcones are considered effective templates for the development of monoamine oxidase (MAO) and cholinesterase (ChE) inhibitors. The present work describes the syntheses of selected 1,3-benzodioxine-containing chalcones ( CD3, CD8 and CD10 ), and their inhibitory activities against MAO-A, MAO-B, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE). Compound CD8 most potently inhibited MAO-B with an IC₅₀ value of 0.026 μM, followed by CD10 and CD3 (1.54 and 1.68 μM, respectively). CD8 potently and non-selectively inhibited MAO-A (IC₅₀ value of 0.023 μM). On the other hand, CD10 and CD8 inhibited AChE with IC₅₀ values of 5.40 and 9.57 μM, respectively. Kinetics and reversibility experiments showed that all synthesized molecules were competitive and reversible inhibitors, and the K_i values of CD8 for MAO-A and MAO-B were 0.018 and 0.0019 μM, respectively. By in vitro and in silico analyses, all compounds were found to have high passive human gastrointestinal absorptions, blood-brain barrier permeabilities, and non-toxicities. Molecular docking simulations revealed that docking affinity of each compound for MAO-B was higher than that for MAO-A. The results indicate that CD8 is a potent non-selective MAO inhibitor, and CD10 is an effective selective MAO-B inhibitor, and both possess AChE inhibitory activity. Therefore, we suggest that CD8 and CD10 be considered potential dual-targeting inhibitors of MAO and AChE for the treatment of various neurodegenerative disorders.     

Disorders of the Cholinergic System in COVID-19 Era—A Review of the Latest Research

The appearance of the SARS-CoV-2 virus initiated many studies on the effects of the virus on the human body. So far, its negative influence on the functioning of many morphological and physiological units, including the nervous system, has been demonstrated. Consequently, research has been conducted on the changes that SARS-CoV-2 may cause in the cholinergic system. The aim of this study is to review the latest research from the years 2020/2021 regarding disorders in the cholinergic system caused by the SARS-CoV-2 virus. As a result of the research, it was found that the presence of the COVID-19 virus disrupts the activity of the cholinergic system, for example, causing the development of myasthenia gravis or a change in acetylcholine activity. The SARS-CoV-2 spike protein has a sequence similar to neurotoxins, capable of binding nicotinic acetylcholine receptors (nAChR). This may be proof that SARS-CoV-2 can bind nAChR. Nicotine and caffeine have similar structures to antiviral drugs, capable of binding angiotensin-converting enzyme 2 (ACE 2) epitopes that are recognized by SARS-CoV-2, with the potential to inhibit the formation of the ACE 2/SARS-CoV-2 complex. The blocking is enhanced when nicotine and caffeine are used together with antiviral drugs. This is proof that nAChR agonists can be used along with antiviral drugs in COVID-19 therapy. As a result, it is possible to develop COVID-19 therapies that use these compounds to reduce cytokine production. Another promising therapy is non-invasive stimulation of the vagus nerve, which soothes the body’s cytokine storm. Research on the influence of COVID-19 on the cholinergic system is an area that should continue to be developed as there is a need for further research. It can be firmly stated that COVID-19 causes a dysregulation of the cholinergic system, which leads to a need for further research, because there are many promising therapies that will prevent the SARS-CoV-2 virus from binding to the nicotinic receptor. There is a need for further research, both in vitro and in vivo. It should be noted that in the functioning of the cholinergic system and its connection with the activity of the COVID-19 virus, there might be many promising dependencies and solutions.     

计算机药物筛选方法探讨

本文论述了计算机药物筛选方法及其应用程序的开发,并通过建立乙酰胆碱酯酶(AchE)抑制剂的筛选模型,检测化合物样品的生物活性,比较生物活性结果与计算机筛选结果,检验了计算机药物筛选方法的可靠性.结果表明,计算机药物筛选方法在创新药物研究中具有重要意义,但需要进一步改进,并结合其他方法来提高它的可靠性.     

甲胺磷抑制乙酰胆碱酯酶活性的压电体声波阻抗分析

采用压电体声波阻抗分析法实时动态监测了乙酰胆碱酯酶对乙酰胆碱的酶促水解过程及农药甲胺磷对酶活性的影响. 监测结果表明, 农药甲胺磷可显著抑制乙酰胆碱的酶促水解, 且水解过程稳态频移值反映的酶活性和农药浓度呈负相关关系, 且甲胺磷的体积比浓度(V甲胺磷/V双重蒸馏水)低至8×10-8依然给出明显的频率响应. 该工作为甲胺磷农药残留检测和研究有机磷农药对蜘蛛神经兴奋性的影响提出了一种可行的新方法.     

Immobilization of glucose oxidase and acetylcholinesterase onto modified polyamide sorbent

Two types of polyamide (PA) sorbents with high specific area were prepared. The effects of solvent type, concentrations of formic acid, and polymer on the porosity characteristics were studied. The sorbent with the highest specific area was obtained by using C₂H₅OH—HCOOH solvent (60% HCOOH) and the rest of the experiments were carried out with this type of sorbent. The possibility of applying the PA sorbent as carrier for immobilization of glucose oxidase (GOD) and acetylcholinesterase (AChE) was investigated. In order to increase the active groups content (necessary for enzyme immobilization), the sorbent was modified with dimethylaminoethylmethacrylate (DMAEM) and 2-acrylamido-2-methylpropensulfonic acid. The amount of the active groups introduced during the modification and the degree of hydrophilicity were determined. The quantity of bound protein and relative activity of GOD and AChE immobilized onto unmodified and modified sorbents were studied. Optimum pH and temperature of the immobilized GOD and AChE were also determined. The influence of three phosphoroorganic compounds on the activity of the immobilized AChE was investigated. Tetrachlorvinvos was found to be the strongest inhibitor, while AChE immobilized onto PA sorbent modified with DMAEM showed the highest stability. The possibility of using immobilized GOD and AChE in a flow-injection system for determination of the concentrations of glucose and phosphoroorganic compounds was studied. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:323–329, 1998     

Vectorially Imprinted Hybrid Nanofilm for Acetylcholinesterase Recognition

Effective recognition of enzymatically active tetrameric acetylcholinesterase (AChE) is accomplished by a hybrid nanofilm composed of a propidium‐terminated self‐assembled monolayer (Prop‐SAM) which binds AChE via its peripheral anionic site (PAS) and an ultrathin electrosynthesized molecularly imprinted polymer (MIP) cover layer of a novel carboxylate‐modified derivative of 3,4‐propylenedioxythiophene. The rebinding of the AChE to the MIP/Prop‐SAM nanofilm covered electrode is detected by measuring in situ the enzymatic activity. The oxidative current of the released thiocholine is dependent on the AChE concentration from ≈0.04 × 10^?6 to 0.4 × 10^?6m . An imprinting factor of 9.9 is obtained for the hybrid MIP, which is among the best values reported for protein imprinting. The dissociation constant characterizing the strength of the MIP‐AChE binding is 4.2 × 10^?7m indicating the dominant role of the PAS‐Prop‐SAM interaction, while the benefit of the MIP nanofilm covering the Prop‐SAM layer is the effective suppression of the cross‐reactivity toward competing proteins as compared with the Prop‐SAM. The threefold selectivity gain provided by i) the “shape‐specific” MIP filter, ii) the propidium‐SAM, iii) signal generation only by the AChE bound to the nanofilm shows promise for assessing AChE activity levels in cerebrospinal fluid.     

Ag+‐Gated Surface Chemistry of Gold Nanoparticles and Colorimetric Detection of Acetylcholinesterase

Chemical regulation of enzyme‐mimic activity of nanomaterials is challenging because it requires a precise understanding of the surface chemistry and mechanism, and rationally designed applications. Herein, Ag⁺‐gated peroxidase activity is demonstrated by successfully modulating surface chemistry of cetyltrimethylammonium bromide‐capped gold nanoparticles (CTAB‐AuNPs). A surface blocking effect of long‐chain molecules on surfaces of AuNPs that inhibit peroxidase activity of AuNPs is found. Ag⁺ ions can selectively bind on the surfaces of AuNPs and competitively destroy CTAB membrane forming Ag⁺@CTAB‐AuNPs complexes to result in enhanced peroxidase activity. Ag⁺@CTAB‐AuNPs show the highest peroxidase activity compared to similar‐sized citrate‐capped and ascorbic acid‐capped AuNPs. Ag⁺@CTAB‐AuNPs can potentially develop into analyte‐responsive systems and exhibit advantages in the optical sensing field. For example, the Ag⁺@CTAB‐AuNPs system shows an enhanced sensitivity and selectivity for acetylcholinesterase activity sensing compared to other methods.