Effects of Different Physical Training Protocols on Metabolic Syndrome Indicators and the Activity of Butyrylcholinesterase in Adolescents: A Randomized Clinical Trial.

Metabolic syndrome (MS) increases the risk of cardiovascular disease and affects children and adolescents. Butyrylcholinesterase (BChE) is an enzyme associated with obesity. The aim of this study was to investigate the effects of different physical training protocols on MS indicators and their relationship with BChE activity. This randomized clinical trial included 80 adolescents randomly assigned to 4 groups (CG: Control Group; ATG: Aerobic Training Group; STG: Strength Training Group; and CTG: Concurrent Training Group). The EFC, lipid profile, glycemia, waist circumference, and blood pressure were analyzed. With the exception of the CG, all the groups underwent training protocols for 12 consecutive weeks, 4 times a week, as follows: (ATG: 75% of heart rate on an electric treadmill; STG: 85% of 1 maximum repetition; CTG: 20 min of aerobic training at the same intensity as the ATG, and 20 min of resistance training in the same way as the STG). The training reduced MS-related biomarkers, such as the lipid profile, glycemia, waist circumference, and blood pressure. STG reduced BChE activity. The training methods led to improvements in the majority of the MS indicators. In addition, aerobic training significantly reduced BChE activity after a 12-week training protocol. The results suggest that different types of exercise can benefit MS.

Indole alkaloids from Ochreinauclea maingayi (Rubiaceae) as butyrylcholinesterase inhibitors and their paralysis effect in transgenic Caenorhabditis elegans.

This study investigated the butyrylcholinesterase (BChE) inhibitory activity of harmane (1), naucledine (2), and dihydrodeglycocadambine (3) isolated from fractions F7 and F9 of Ochreinauclea maingayi. Both fractions demonstrated significant inhibition, exceeding 80%, against BChE at 100 µg/mL. Compound 2, is the most potent inhibitor, exhibiting an IC50 value of 22.08 µM, followed by 1 and 3 (IC50 23.96 and 30.32 µM, respectively). Docking studies revealed that 1 and 2 effectively bind to BChE, with binding energies of -51.24 and -57.17 kcal/mol, respectively. Kinetic analysis of 2 indicated mixed-mode inhibition of BChE, with a Ki of 6.08 µM. In the paralysis assay, 1 showed a weak delay in paralysis and reduced the paralysis ratio from 72.59 ± 4.7% to 60.00 ± 7.0% (12.59% reduction) followed by 2 with 70.00 ± 1.7% (2.59% reduction) compared with negative standard (DMSO 0.1%) on human amyloid ß-protein in a transgenic Caenorhabditis elegans (CL4176) model.

Synthesis and biological evaluation of novel aminoquinolines with an n-octyl linker: Impact of halogen substituents on C(7) or a terminal amino group on anticholinesterase and BACE1 activity.

Alzheimer's disease is age-related multifactorial neurodegenerative disease manifested by gradual loss of memory, cognitive decline and changes in personality. Due to rapid and continuous growth of its prevalence, the treatment of Alzheimer's disease calls for development of new and efficacies drugs, especially those that could be able to simultaneously act on more than one of possible targets of action. Aminoquinolines have proven to be a highly promising structural scaffold in the design of such a drug as cholinesterases and ß-secretase 1 inhibitors. In this study, we synthesised twenty-two new 4-aminoquinolines with different halogen atom and its position in the terminal N-benzyl group or with a trifluoromethyl or a chlorine as C(7)-substituents on the quinoline moiety. All compounds were evaluated as multi-target-directedligands by determining their inhibition potency towards human acetylcholinesterase, butyrylcholinesterase and ß-secretase 1. All of the tested derivatives were very potent inhibitors of human acetylcholinesterase and butyrylcholinesterase with inhibition constants (Ki) in the nM to low µM range. Most were estimated to be able to cross the blood-brain barrier by passive transport and were nontoxic toward cells that represented the main models of individual organs.

Characterization of Phenolic Profile and Biological Properties of Astragalus membranaceus Fisch. ex Bunge Commercial Samples.

Astragalus membranaceus Fisch. ex Bunge (syn. Astragalus mongholicus Bunge) is one of the notable medicinal and food plants. Therefore, the aim of this study was to calculate the phenolic composition and antioxidant, antimicrobial, as well as enzyme inhibitory [acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYR)] activities with chemometric approaches of the hydromethanolic and water extracts of commercial A. membranaceus samples. Ten individual phenolic compounds were determined using high-performance liquid chromatography (HPLC), and only quercetin was found at a level of above 80 µg/g DW in both extracts. Moreover, the highest antioxidant activity in DPPH, FRAP, ABTS, and CUPRAC assays was found in the sample containing the roots in loose form from USA. A. membranaceus extracts displayed the inhibition zone diameters within the range from 10 to 22 mm antimicrobial activity against S. aureus, while there were no inhibition zones in any extracts in case of E. coli. The extracts of A. membranaceous showed an inhibition rate below 40% against TYR, and among tested extracts, only two samples were able to inhibit BChE with IC50 values of above 30 µg/mL. Correlation analysis showed a highly positive relationship between their phenolic composition and antioxidant activity. Concluding, the obtained results confirmed that A. membranaceus commercial samples could be an important dietary source of natural antioxidants.

A Series of Novel 1-H-isoindole-1,3(2H)-dione Derivatives as Acetylcholinesterase and Butyrylcholinesterase Inhibitors: In Silico, Synthesis and In Vitro Studies.

The derivatives of isoindoline-1,3-dione are interesting due to their biological activities, such as anti-inflammatory and antibacterial effects. Several series have been designed and evaluated for Alzheimer's therapy candidates. They showed promising activity. In this work, six new derivatives were first tested in in silico studies for their inhibitory ability against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. Molecular docking and molecular dynamic simulation were applied. Next, these compounds were synthesized and characterized by 1H NMR, 13C NMR, FT-IR, and ESI-MS techniques. For all imides, the inhibitory activity against AChE and BuChE was tested using Ellaman's method. IC50 values were determined. The best results were obtained for the derivative I, with a phenyl substituent at position 4 of piperazine, IC50 = 1.12 µM (AChE) and for the derivative III, with a diphenylmethyl moiety, with IC50 = 21.24 µM (BuChE). The compounds tested in this work provide a solid basis for further structural modifications, leading to the effective design of potential inhibitors of both cholinesterases.

Design, Synthesis, and Invitro Pharmacological Evaluation of Novel Resveratrol Surrogate Molecules against Alzheimer's Disease.

A series of resveratrol surrogate molecules were designed, synthesized and biologically evaluated for inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) along with anti-oxidant activity as potential novel multifunctional agents against Alzheimer's disease (AD). Six novel compounds were synthesized by reacting (E)-4-(3,5-Dimethoxystyryl) aniline with benzaldehyde and some selected derivatives of benzaldehyde in the presence of ethanol and a few drops of glacial acetic acid which followed the general scheme involved in the formation of Schiff bases. The spectral analysis data including FT-IR, 1H-NMR, 13C-NMR, and Mass spectroscopy results were found to be in good agreement with the newly synthesized compounds (Resveratrol Surrogate Molecules 1-6). The synthesized compounds were evaluated for their dual cholinesterase inhibitory activities, cytotoxic effect, and anti-oxidant potential. The results showed that compound RSM5 showed potent inhibitory activity against AChE and BChE. In, addition the cytotoxicity of the compound RSM5 is less and found to be within the desirable limit indicating the potential safety of RSM5. Also, it possesses substantial anti-oxidant activity which qualifies RSM5 as an anti-AD agent. Taken together, these findings demonstrate that the molecule RSM5 had the most multifunctional properties and could be a promising lead molecule for the future development of drugs for Alzheimer's treatments.

Chiral pyrrolidines as multipotent agents in Alzheimer and neurodegenerative diseases.

In pharmaceutical science and drug design the versatility of the pyrrolidine scaffold relating to spatial arrangement, synthetic accessibility and pharmacological profile is a largely explored and most likely interesting one. Nonetheless, few evidences suggest the pivotal role of pyrrolidine as scaffold for multipotent agents in neurodegenerative diseases. We then challenged the enrolling in the field of Alzheimer disease of so far not ravelled targets of this chemical cliché with a structure based and computer-aided design strategy focusing on multi-target action, versatile synthesis as well as pharmacological safeness. To achieve these hits, ten enantiomeric pairs of compounds were obtained and tested, and the biological data will be here presented and discussed. Among the novel compounds, coumarin and sesamol scaffolds containing analogues resulted promising perspectives.

Acetylcholinesterase and butyrylcholinesterase co-immobilized on a copper containing Prussian blue modified electrode for the broad screening of insecticides.

We have developed a bienzymatic biosensor that contains acetylcholinesterase together with butyrylcholinesterase co-immobilized on the same electrode modified with a stabilized copper containing Prussian blue electrodeposited on electrodes coated with 4-aminothiophenol monolayer using diazonium chemistry and copper nanoparticles for improved sensitivity. There are organophosphorus and carbamate neurotoxic insecticides that inhibit only one of the two enzymes, e.g., pirimicarb inhibits butyrylcholinesterase at much lower concentrations than acetylcholinesterase while methomyl inhibits only acetylcholinesterase. Our system is simple and in a single measurement provides a sensitive signal for insecticides' presence based on the inhibition of the enzyme with the highest affinity for each toxic compound. The limits of detection are 50 ng/mL pirimicarb for the bienzymatic biosensor in comparison with 400 ng/mL pirimicarb for the acetylcholinesterase biosensor and 6 ng/mL methomyl for the bienzymatic biosensor, while inhibition is obtained for the butyrylcholinesterase biosensor at 700 ng/mL.

Unveiling piperazine-quinoline hybrids as potential multi-target directed anti-Alzheimer's agents: design, synthesis and biological evaluation.

Multi-target directed ligands (MTDLs) have recently been popularized due to their outstanding efficacy in combating the complicated features of Alzheimer's disease. This study details the synthesis of piperazine-quinoline-based MTDLs through a multicomponent Petasis reaction, targeting multiple factors such as AChE, BuChE, metal chelation to restore metal dyshomeostasis, and antioxidant activity. Some of the synthesized compounds exhibited notable inhibitory activity against AChE and BuChE enzymes at specific concentrations. Among the synthesized compounds compound (95) containing a 4-chloroaniline moiety and a 4-methoxybenzyl group displayed the most promising inhibitory activities against AChE (IC50 3.013 µM) and BuChE (IC50 = 3.144 µM). Compound (83) featuring 2-methoxyaniline and 4-fluorobenzyl substituents, exhibited the highest BuChE inhibition (IC50 1.888 µM). Notably, compound (79) demonstrated 93-times higher selectivity for BuChE over AChE. Molecular docking and molecular dynamics simulations were also performed to explore the binding modes and stability of these compounds with the AChE amd BuChE proteins. Further, kinetics study was performed against AChE for comounds (83 and 95) which indicated mixed inhibition of the enzyme by these compounds, Amongs the synthesized compounds, nine compounds were assessed for their antioxidant activity, displaying significant antioxidant properties with IC50 values ranging from 156 µM to 310 µM. Moreover, all the compounds demonstrated metal chelating tendency with Cu+2, Zn+2, Fe+2, Fe+3 and Al+3. This study provides insights into the design of novel MTDLs, highlighting compound (95) as a potential candidate for combating Alzheimer's disease.

Mass spectrometry detection of organophosphorus pesticide adducts on butyrylcholinesterase and albumin.

This study established a method to prepare and detect OPs adducts on butyrylcholinesterase (BChE) and human serum albumin (HSA). OPs (methyl paraoxon, ethyl paraoxon, methyl parathion, parathion) were incubated with BChE or HSA in vitro, and the adducts of OPs-BChE or OPs-HSA were prepared and qualitatively analyzed by ultra-performance liquid chromatography data-dependent high-resolution tandem mass spectrometry (UPLC-ddHRMS/MS). The amounts of BChE and HSA in the incubating systems were varied and the resulting amounts of the adducts were determined using linear regression. OPs-BChE in the blood were isolated by immunomagnetic separation (IMS), and then digested into the OPs-nonapeptide adduct by pepsin. The proteins in the remaining blood plasma were precipitated and digested by pronase to OPs-tyrosines(OPs-Tyr), which were quantified by UPLC-ddHRMS/MS. 4 OPs-nonapeptides and 4 OPs-Tyr adducts were obtained through the process above. The relative mass deviation of incubated adducts between the actual and theoretical exact masses was less than 10 ppm, and further confirmed by fragmentation mass spectra analysis. Calibration curves were linear for all adducts with a coefficient of determination value (R2) ≥0.995. The limits of detection (LOD) and limits of quantification (LOQ) for adducts detected by MS ranged from 0.05 to 1.0 ng/mL, and from 0.1 to 2.0 ng/mL, respectively. The recovery percentages for adducts ranged from 76.1 % to 107.1 %, matrix effects ranged from 83.4 % to 102.1 %. The inter-day and intra-day precision were 6.1-10.1 % and 6.9-12.9 % for adducts. This study provides a new reference method for the detection of organophosphorus pesticide poisoning. In addition, two blood samples with organophosphorus poisoning were tested by the designed method, and the corresponding adducts were detected in both samples.

Near-infrared fluorescent probe for ultrasensitive detection of organophosphorus pesticides and visualization of their interaction with butyrylcholinesterase in living cells.

The toxicity of organophosphorus pesticides (OPs) can catastrophically cause liver cell damage and inhibit the catalytic activity of cholinesterase. We designed and synthesized a near-infrared fluorescent probe HP-LZB with large Stokes shift which can specifically identify and detect butyrylcholinesterase (BChE) and visually explore the interaction between OPs and endogenous BChE in living cells. Fluorescence was turned on when HP-LZB was hydrolyzed into HP-LZ in the presence of BChE, and OPs could inhibit BChE's activity resulting in a decrease of fluorescence. Six OPs including three oxon pesticides (paraoxon, chlorpyrifos oxon and diazoxon) and their corresponding thion pesticides (parathion, chlorpyrifos and diazinon) were investigated. Both in vitro and cell experiments indicated that only oxon pesticides could inhibit BChE's activity. The limits of detection (LODs) of paraoxon, chlorpyrifos oxon and diazoxon were as low as 0.295, 0.007 and 0.011 ng mL-1 respectively and the recovery of OPs residue in vegetable samples was satisfactory. Thion pesticides themselves could hardly inhibit the activity of BChE and are only toxic when they are converted to their corresponding oxon form in the metabolic process. However, in this work, thion pesticides were found not be oxidized into their oxon forms in living HepG2 cells due to the lack of cytochrome P450 in hepatoma HepG2 cell lines. Therefore, this probe has great application potential in effectively monitoring OPs in real plant samples and visually exploring the interaction between OPs and BChE in living cells.

Affinity ultrafiltration based metabolomic profiling directed discovery novel butyrylcholinesterase inhibitors from Uncaria sessilifructus.

The butyrylcholinesterase (BChE) is an attractive target for treating Alzheimer's disease. In this study, we report the discovery of five new monoterpene indole alkaloids (MIAs) along with three known analogues from Uncaria sessilifructus Roxb. as BChE inhibitors using affinity ultrafiltration based metabolomic profiling directed isolation strategy. Their structures were well identified through comprehensive spectroscopic and chiroptical analyses. Compounds 1-2 featured unique glycosidic linkages with 1,3-dioxane structure. All the compounds exhibited BChE inhibitory bioactivity without any cytotoxic effects. Enzymatic kinetic and molecular docking analyses of compounds 1 and 6 demonstrated their inhibiting mechanisms and binding patterns to BChE. These findings provide a valuable workflow for efficiently screening ligands that bind to proteins, and scientific recognition in the discovery of BChE inhibitors for treating neurodegenerative disorders.

The selective butyrylcholinesterase inhibitor UW-MD-95 shows symptomatic and neuroprotective effects in a pharmacological mouse model of Alzheimer's disease.

AIMS: Alzheimer's disease (AD) is a devastating dementia characterized by extracellular amyloid-ß (Aß) protein aggregates and intracellular tau protein deposition. Clinically available drugs mainly target acetylcholinesterase (AChE) and indirectly sustain cholinergic neuronal tonus. Butyrylcholinesterase (BChE) also controls acetylcholine (ACh) turnover and is involved in the formation of Aß aggregates and senile plaques. UW-MD-95 is a novel carbamate-based compound acting as a potent pseudo-irreversible BChE inhibitor, with high selectivity versus AChE, and showing promising protective potentials in AD. METHODS: We characterized the neuroprotective activity of UW-MD-95 in mice treated intracerebroventricularly with oligomerized Aß25-35 peptide using behavioral, biochemical, and immunohistochemical approaches. RESULTS: When injected acutely 30 min before the behavioral tests (spontaneous alternation in the Y-maze, object recognition, or passive avoidance), UW-MD-95 (0.3-3 mg/kg) showed anti-amnesic effects in Aß25-35-treated mice. When injected once a day over 7 days, it prevented Aß25-35-induced memory deficits. This effect was lost in BChE knockout mice. Moreover, the compound prevented Aß25-35-induced oxidative stress (assessed by lipid peroxidation or cytochrome c release), neuroinflammation (IL-6 and TNFα levels or GFAP and IBA1 immunoreactivity) in the hippocampus and cortex, and apoptosis (Bax level). Moreover, UW-MD-95 significantly reduced the increase in soluble Aß1-42 level in the hippocampus induced by Aß25-35. CONCLUSION: UW-MD-95 appeared as a potent neuroprotective compound in the Aß25-35 model of AD, with potentially an impact on Aß1-42 accumulation that could suggest a novel mechanism of neuroprotection.

Reactivators of butyrylcholinesterase inhibited by organophosphorus compounds.

In this review, the current progress in the research and development of butyrylcholinesterase (BChE) reactivators is summarised and the advantages or disadvantages of these reactivators are critically discussed. Organophosphorus compounds such as nerve agents (sarin, tabun, VX) or pesticides (chlorpyrifos, diazinon) cause irreversible inhibition of acetylcholinesterase (AChE) and BChE in the human body. While AChE inhibition can be life threatening due to cholinergic overstimulation and crisis, selective BChE inhibition has presumably no adverse effects. Because BChE is mostly found in plasma, its activity is important for the scavenging of organophosphates before they can reach AChE in the central nervous system. Therefore, this enzyme in combination with its reactivator can be used as a pseudo-catalytic scavenger of organophosphates. Three structural types of BChE reactivators were found, i.e. bisquaternary salts, monoquaternary salts and uncharged compounds. Although the reviewed reactivators have certain limitations, the promising candidates for BChE reactivation were found in each structural group.

Identification of novel benzothiazole-thiadiazole-based thiazolidinone derivative: in vitro and in silico approaches to develop promising anti-Alzheimer's agents.

Aim: The present study describes benzothiazole derived thiazolidinone based thiadiazole derivatives (1-16) as anti-Alzheimer agents. Materials & methods: Synthesis of benzothiazole derived thiazolidinone based thiadiazole derivatives was achieved using the benzothiazole bearing 2-amine moiety. These synthesized compounds were confirmed via spectroscopic techniques (1H NMR, 13C NMR and HREI-MS). These compounds were biologically evaluated for their anti-Alzheimer potential. Binding interactions with proteins and drug likeness of the analogs were explored through molecular docking and ADMET analysis, respectively. In the novel series, compound-3 emerged as the most potent inhibitor when compared with other derivatives of the series. Conclusion: The present study provides potent anti-Alzheimer's agents that can be further optimized to discover novel anti-Alzheimer's drugs.

[Box: see text].

Ratiometric fluorescence and colorimetric strategies for assessing activity of butyrylcholinesterase in human serum using g-C3N4 nanosheets, silver ion and o-phenylenediamine.

Ratiometric fluorescence and colorimetric strategies for detecting activity of butyrylcholinesterase (BChE) in human serum were developed by using g-C3N4 nanosheets, silver ion (Ag+) and o-phenylenediamine (OPD) as chromogenic agents. The oxidation-reduction reaction of OPD and Ag+ generates 2,3-diaminophenazine (oxOPD). Under exciation at 370 nm, g-C3N4 nanosheets and oxOPD emit fluorescence at 440 nm (F440) and 560 nm (F560), respectively. Additionally, oxOPD exhibits quenching ability towards g-C3N4 nanosheets via photoinduced electron transfer (PET) process. Thiocholine (TCh), as a product of BChE-catalyzed hydrolysis reaction of butylthiocholine iodide (BTCh), can coordinate with Ag+ intensively, and consequently diminish the amount of free Ag+ in the testing system. Less amount of free Ag+ leads to less production of oxOPD, resulting in less fluorescence quenching towards g-C3N4 nanosheets as well as less fluorescence emission of oxOPD. Therefore, by using g-C3N4 nanosheets and oxOPD as fluorescence indicators, the intensity ratio of their fluorescence (F440/F560) was calculated and employed to evaluate the activity of BChE. Similarly, the color variation of oxOPD indicated by the absorbance at 420 nm (ΔA420) was monitored for the same purpose. These strategies were validated to be sensitive and selective for detecting BChE activity in human serum, with limits of detection (LODs) of 0.1 U L-1 for ratiometric fluorescence mode and 0.7 U L-1 for colorimetric mode.

Biological and computational evaluation of novel benzofuranyl derivatives as acetylcholinesterase and butyrylcholinesterase inhibitors.

Aim: A highly efficient one-step method has been developed for the synthesis of benzofuranyl derivatives from 2-benzoylcyclohexane-1-carboxylic acid derivatives using chlorosulfonyl isocyanate. This novel method provides a practical, cost-effective and efficient approach. Materials & methods: The inhibitory effects of benzofuranyl derivatives on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes were investigated. Ki values were determined to range from 0.009 to 0.61 µM for AChE and 0.28 to 1.60 µM for BChE. Molecular docking analysis provided insights into the interaction modes and binding patterns of these compounds with AChE and BChE. Conclusion: Kinetic findings of our study suggest that some of our compounds exhibited more effective low micromolar inhibition compared with the reference, and these derivatives could be used to design more powerful agents.

[Box: see text].

New insights into butyrylcholinesterase: Pharmaceutical applications, selective inhibitors and multitarget-directed ligands.

Butyrylcholinesterase (BChE), also known as pseudocholinesterase and serum cholinesterase, is an isoenzyme of acetylcholinesterase (AChE). It mediates the degradation of acetylcholine, especially under pathological conditions. Proverbial pharmacological applications of BChE, its mutants and modulators consist of combating Alzheimer's disease (AD), influencing multiple sclerosis (MS), addressing cocaine addiction, detoxifying organophosphorus poisoning and reflecting the progression or prognosis of some diseases. Of interest, recent reports have shed light on the relationship between BChE and lipid metabolism. It has also been proved that BChE is going to increase abnormally as a compensator for AChE in the middle and late stages of AD, and BChE inhibitors can alleviate cognitive disorders and positively influence some pathological features in AD model animals, foreboding favorable prospects and potential applications. Herein, the selective BChE inhibitors and BChE-related multitarget-directed ligands published in the last three years were briefly summarized, along with the currently known pharmacological applications of BChE, aiming to grasp the latest research directions. Thereinto, some emerging strategies for designing BChE inhibitors are intriguing, and the modulators based on target combination of histone deacetylase and BChE against AD is unprecedented. Furthermore, the involvement of BChE in the hydrolysis of ghrelin, the inhibition of low-density lipoprotein (LDL) uptake, and the down-regulation of LDL receptor (LDLR) expression suggests its potential to influence lipid metabolism disorders. This compelling prospect likely stimulates further exploration in this promising research direction.

Exploring New 5-Nitroimidazole Derivatives As Potent Acetylcholinesterase and Butyrylcholinesterase Enzyme Inhibitors.

Discovering new compounds capable of inhibiting physiologically and metabolically significant drug targets or enzymes is of paramount importance in biological chemistry. With this aim, new 5-nitroimidazole derivatives (1-4) were designed and synthesized, and their inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) were discovered using acetyl (butyryl) thiocholine and Ellman's reagents for spectrophotometric assay. The inhibitory profiles of the synthesized compounds were assessed by comparing their IC50 and Ki values. Results demonstrate significant inhibitory activity of all synthesized compounds against both AChE and BuChE compared to the reference compound, donepezil. Notably, compound 4 exhibited dual inhibition of these enzymes, showing the highest activity against Electrophorus electricus AChE (EeAChE) with a Ki value of 0.024±0.009 nM and against equine BuChE (eqBuChE) with a Ki value of 0.087±0.017 nM. Furthermore, molecular modeling was conducted to study the interaction modes of the most potent compound (4) and donepezil in the active site of their related enzymes' crystal structures (PDB ID: 4EY7 and 4BDS, respectively). Additionally, drug-likeness, ADME, and toxicity profiles of the compounds and metronidazole were predicted. The above results indicated that the dual inhibition of these enzymes is considered as a promising strategy for the treatment of neurological disorder especially Alzheimer's disease.

Structure-based design of multitargeting ChEs-MAO B inhibitors based on phenyl ring bioisosteres: AChE/BChE selectivity switch and drug-like characterization.

A structure-based drug design approach was focused on incorporating phenyl ring heterocyclic bioisosteres into coumarin derivative 1, previously reported as potent dual AChE-MAO B inhibitor, with the aim of improving drug-like features. Structure-activity relationships highlighted that bioisosteric rings were tolerated by hMAO B enzymatic cleft more than hAChE. Interestingly, linker homologation at the basic nitrogen enabled selectivity to switch from hAChE to hBChE. In the present work, we identified thiophene-based isosteres 7 and 15 as dual AChE-MAO B (IC50 = 261 and 15 nM, respectively) and BChE-MAO B (IC50 = 375 and 20 nM, respectively) inhibitors, respectively. Both 7 and 15 were moderately water-soluble and membrane-permeant agents by passive diffusion (PAMPA-HDM). Moreover, they were able to counteract oxidative damage induced by both H2O2 and 6-OHDA in SH-SY5Y cells and predicted to penetrate into CNS in a cell-based model mimicking blood-brain barrier. Molecular dynamics (MD) simulations shed light on key differences in AChE and BChE recognition processes promoted by the basic chain homologation from 7 to 15.