Inhibition Of Enzyme Acetylcholinesterase Research Articles

Preparation and characterization of AChE immobilized magnetic bio-nanocomposites (Fe3O4@Cht/Au) for pesticide detection

Free enzymes cause difficulties in many applications due to their insufficient stability, loss of activity in a short time, and most importantly, although they are costly, they are used only once in reactions, lose their effect and cannot be recovered from the environment. Magnetic nanoparticles coated with biocompatible polymeric material are potential candidates for promising enzyme carriers due to their multifunctional pore surfaces, easy removal from the environment provided by the magnetization, ability to main stability under various harsh conditions. This study prepared a biosensor candidate based on the inhibiting acetylcholinesterase enzyme by organophosphate pesticides from chitosan-coated magnetic nanoparticles doped with gold. Transmission electron microscopy, scanning electron microscopy, X-ray diffraction diffractometry, and Fourier transform infrared spectroscopy analysis confirmed the structure of synthesized nanocomposites. Magnetic characteristics of the nanocomposites were assessed using VSM. Bio-nanocomposite (Fe3O4@Cht/Au/AChE) was used to determine environmental pollutants qualitatively. Remediation of organophosphate-containing wastewater is an essential issue for environmental sustainability. In this work, Dichlorvos and Chlorpyrifos were selected as organic pollutants to assess the enzymatic activity of immobilized Fe3O4@Cht/Au/AChE. Optimum conditions for AChE enzyme were immobilized nanostructures (Fe3O4@Cht/Au/AChE) were determined. The optimum pH for the immobilized enzyme was found to be 8, and the optimum temperature was found to be 60 °C. Retained immobilized enzyme activity is found to be around 50% for the 20th reuse. In the presence of 150 µL pesticide, retained immobilized enzyme activity is found to be around 25%. Method validation was performed for pesticides. When using immobilized AChE, the LOD (limit of detection)-LOQ (limit of quantitation) values for Dichlorovos and Chlorpyrifos was obtained in the range of 0.0087–0.029 nM and 0.0014–0.0046 nM, respectively. The relative standard deviation (RSD%) values, which are indicators of precision, were found to be below 2%.

Competitive Inhibition and Synergistic Effects of Nutraceutical and Metabolite Molecules on Anti-Acetylcholinesterase Activity

The rapidly increasing prevalence of Alzheimer's disease (AD) poses a significant global public health threat. While medications such as Donepezil, Galantamine, and Rivastigmine are used, their serious side effects and limited healing fail to provide a definite cure. Consequently, combination therapies are being explored to enhance the efficacy of existing drugs. This study aims to evaluate the anti-acetylcholinesterase activities of previously identified nutraceutical and metabolite compounds, namely Queuine, Etoperidone, and Thiamine. Combined use of Queuine with Donepezil, Etoperidone, and Thiamine on acetylcholinesterase enzyme inhibition is also evaluated. The effects of the drug combinations on cell viability and acetylcholinesterase inhibition were investigated by using safe doses determined for each drug. The cytotoxic effect of drug combinations was investigated on the SH-SY5Y cell line using the RTCA method. All the individual or drug combinations were non-toxic to neuronal cells. Anti-acetylcholinesterase activities were estimated by Ellman’s method yielding the inhibition percentages as 70%, 61%, 45%, and 51% for Donepezil, Etoperidone, Queuine, and Thiamine, respectively. When drug combinations were analyzed, competitive inhibition resulted for Queuine+Donepezil and Queuine+Thiamine, the enzyme inhibition percentages being diminished to 47% and 21%, respectively. A significant synergistic effect was observed for Queuine+Etoperidone with the highest inhibition of 74%. This study provides the first evidence of the nutraceutical molecule Queuine's impact on acetylcholinesterase inhibition and the synergistic effect of Queuine and Etoperidone as a potent drug combination surpassing the effectiveness of Donepezil. Queuine and Etoperidone synergism may serve as a potential AD treatment by further in vivo validations.

Neuroprotective properties of UV-C treated Bacopa floribunda leaves: in vitro and in vivo studies

This study investigated the effect of UV-C irradiation on antioxidant, cholinergic and neuroprotective properties of Bacopa floribunda leaves in scopolamine-induced rats. In vitro study was done by the determination of phenolics, flavonoid, total antioxidant capacity, 2, 2-diphenyl-1-picrylhydrazyl scavenging activity, inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Loss of memory was induced in Wistar rats pre-treated with extracts of Bacopa floribunda using scopolamine (2 mg/kg) administered intraperitoneally. Behavioural studies using elevated plus maze (EPM) and biochemical analysis on the were carried out. Exposure to UV-C radiation increased the phenolics, flavonoid, antioxidant and inhibitory properties against AChE and BChE of the Bacopa floribunda leaves. The administration of scopolamine caused significant increase in the activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes, but decrease in the activities of antioxidant enzymes and enhanced generation of malondialdehyde and nitric oxide in vivo. The loss of memory and Biochemical analysis in scopolamine-induced rats was ameliorated by treatment with UV-C treated Bacopa floribunda (TBF) extracts. Treatment with TBF improved memory retention and ameliorated oxidative damage in hippocampus of scopolamine treated rats.

The impact of seasonal variation on the composition of the volatile oil of Polyalthia suberosa (Roxb.) Thwaites leaves and evaluation of its acetylcholinesterase inhibitory activity

BackgroundPolyalthia suberosa (Roxb.) Thwaites (Annonaceae) is a medicinal plant that has been reported for its various pharmacological potentials, such as its anti-inflammatory, analgesic, antioxidant, and neuropharmacological activities. This study aimed to analyze the leaf essential oils of P. suberosa (PSLO) collected in different seasons, to evaluate the acetylcholinesterase inhibitory activity, and to corroborate the obtained results via in-silico molecular docking studies.MethodsThe leaf essential oils of P. suberosa collected in different seasons were analyzed separately by GC/MS. The acetylcholinesterase inhibitory activity of the leaves oil was assessed via colorimetric assay. In-silico molecular docking studies were elucidated by virtual docking of the main compounds identified in P. suberosa leaf essential oil to the active sites in human acetylcholinesterase crystal structure.ResultsA total of 125 compounds were identified where D-limonene (0.07 − 24.7%), α-copaene (2.25 − 15.49%), E-β-caryophyllene (5.17 − 14.42%), 24-noroleana-3,12-diene (12.92%), β-pinene (0.14 − 8.59%), and α-humulene (2.49–6.9%) were the most abundant components. Results showed a noteworthy influence of the collection season on the chemical composition and yield of the volatile oils. The tested oil adequately inhibited acetylcholinesterase enzyme with an IC50 value of 91.94 µg/mL. Additionally, in-silico molecular docking unveiled that palmitic acid, phytol, p-cymene, and caryophyllene oxide demonstrated the highest fitting scores within the active sites of human acetylcholinesterase enzyme.ConclusionsFrom these findings, it is concluded that P. suberosa leaf oil should be evaluated as a food supplement for enhancing memory.

CG-MS, Radical Scavenging, Acetylcholinesterase Inhibition, Antifungal and Molecular Docking Studies of Essential Oil from the Leaves of Tapirira guianensis Aubl

The species Tapirira guianensis Aubl is used in folk medicine to treat leprosy, diarrhea, and syphilis. The present study aims to evaluate the chemical composition and the antioxidant, anticholinesterase, and antifungal potential of the essential oil from T. guianensis leaves. The plant material was collected at Arco Estadual do Cocó, with prior authorization from the Municipal Environment Department. The essential oil was extracted through the hydrodistillation process with a Clevenger-type apparatus, and the constituents were evaluated through Gas Chromatography coupled to Mass Spectrometry (GC-MS). The antioxidant potential was assessed through free radicals: DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS+ (2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)) in a 96-well plate. Antifungal activity was evaluated using the Clinical Laboratory Standards Institute - M38-A protocol (CLSI, 2018). Gas chromatography coupled with mass spectrometry revealed the presence of constituents such as eugenol (59.00%), α-copaene (0.40%), β-caryophyllene (29.91%), α-humulene in T. guianensis. The essential oil demonstrated very promising antioxidant and anticholinesterase potential in In vitro studies. Molecular docking regarding acetylcholinesterase enzyme inhibition revealed that α-copaene has superior action compared to the drug physostigmine. The results of molecular docking for Candida albicans showed that α-copaene and α-humulene interacted in the same binding region as the PepA inhibitor against SAP5. This indicates their action is similar to the aspartic protease inhibitor, in addition to the possibility of a synergistic effect with the drug fluconazole. This is the first study of the biological potential of the essential oil from T. guianensis leaves, thus revealing its high potential for future studies in the scientific community. Therefore, we can infer that the essential oil of T. guianensis is a source of antioxidant, anticholinesterase, and antifungal constituents, with promising therapeutic potential in the management of Alzheimer's disease and Candida infections.

In Silico Investigation of Novel Compounds as Inhibitors of Acetylcholinesterase Enzyme for the Treatment of Alzheimer's Diseases.

Alzheimer's disease (AD) is a "progressive, neurodegenerative disease that occurs when nerve cells in the brain die." There are only 4 drugs approved by the United States Food and Drug Administration (FDA). Three (donepezil, rivastigmine, and galantamine) out of these four drugs are anticholinesterase inhibitors, while the fourth one memantine is an N-methyl-D-aspartate (NMDA) receptor inhibitor. Currently, two immunotherapy drugs that target amyloid protein (donanemab and lecanemab) are being considered for the treatment of Alzheimer's disease at an early stage. All these drug molecules are still not the complete answer to the treatment of Alzheimer's disease. A recent report from the Office of National Statistics showed that AD is the leading cause of death in 2022. Therefore, there is an urgency to develop more drugs that can treat AD. Based on this urgency, we aim to investigate how bioactive and already approved drugs could be repurposed for inhibiting the anticholinesterase enzyme using computational studies. To achieve this, the data science tool-Python coding was compiled on Jupyter Notebook to mine bioactive compounds from the ChEMBL database. The most bioactive compounds obtained were further investigated using Molecular Operating Environment (MOE) software to carry out molecular docking and ligand analysis, and this was followed by molecular dynamics simulation production at 35 ns using GROMACS 2022.4 on Archer 2 machine. The molecular dynamic analysis was carried out using HeroMDanalysis software. Data mining of the ChEMBL database was carried out for lipase inhibitors, and this gave CHEMBL-ID 1240685, a peptide molecule, the most active compound at the time of data mining. Further literature studies gave Zoladex an FDA-approved drug for the treatment of breast cancer as another compound of interest. The in silico studies were carried out against the anticholinesterase enzyme using two FDA-approved drugs donepezil and galantamine as a template for comparing the in silico activities of the repurposed drugs. A very useful receptor for this study was PDB-1DX6, a cocrystallized galantamine inhibitor of acetylcholinesterase enzyme. The molecular docking analysis (using ligand interactions) and molecular dynamic analysis (root mean square deviation (RMSD) and root mean square fluctuation (RMSF)) showed that the two peptide molecules CHEMBL-1240685 and Zoladex gave the best binding energy and stability when compared to the FDA-approved drugs (donepezil and galantamine). Finally, further literature studies revealed that Zoladex affects memory reduction; therefore, it was dropped as a possible repurposed drug. Our research showed that CHEMBL-1240685 is a potential compound that could be investigated for the inhibition of anticholinesterase enzyme and might be another drug molecule that could be used to treat Alzheimer's disease.

Content analysis, nanoparticle forming potential and acaricidal effects on Tick (Hyalomma marginatum) of essential oils from two common Thymbra species

In this study, the fatty acid, essential oil and aroma composition of Thymbra sintenisii Bornm. & Aznav. subsp. sintenisii Bornm. & Aznav (TSS) and Thymbra sintenisii Bornm. & Azn. subsp. isaurica P.H.Davis (TSI) were determined by GC-MS. The cytotoxic activity was determined with MTT assay and antioxidant activities were determined with DPPH, ABTS, CUPRAC methods. Urease, acetyl, butyryl, angiotensin, α-amylase, tyrosinase, elastase, and collagenase enzyme inhibition activities of these species were also determined. The acaricidal effects of essential oils from aerial parts of TSS and TSI on ticks and the nanoparticle formation potential of their essential oils with AgNO3 were determined and compared. The main components of TSS essential oil and aroma were determined as carvacrol and o-cemen (66.78 and 35.44%, respectively), the major components of TSI essential oil and aroma were carvacrol and γ-terpinene (63.78 and 31.44%, respectively). The species exhibited remarkably high antioxidant activity, particularly in the ABTS and CUPRAC methods. It was also determined that the butyrylcholinesterase and acetylcholinesterase enzyme inhibition activities (Inhibition%: 76.12±0.83 and 74.13±0.33, respectively) of the species were quite high. Moderate antimicrobial activity against the bacteria was observed for both essential oils, with MIC values ranging from 312 to 1250 μg/mL. Moreover, essential oils of these species showed good acaricidal activity on Hyalomma marginatum (LC50: 11.82 μg/mL for TSS; LC50: 57.64 μg/mL for TSI). The high antioxidant, anticholinesterase, and acaracidal activities observed in both species are attributed to the presence of carvacrol in their essential oils. The species have potential to be used in food supplements-preservatives, pharmaceutical industry.

Investigation, scaffold hopping of novel donepezil-based compounds as anti-Alzhiemer's agents: synthesis, in-silico and pharmacological evaluations.

Alzheimer's disease (AD) is a multifaceted neurodegenerative condition. The pathogenesis of AD is highly intricate and the disease is apparent in the aged population ~ 50-70years old. Even after > 100years of research, the root origin of AD and its pathogenesis is unclear, complex and multifaceted. Herein, we have designed and synthesized 9 novel molecules with three different heterocyclic scaffolds namely pyrrolidone-2-one, quinoline & indoline-2-one to imitate and explore the novel chemical space around donepezil. The synthesized molecules were evaluated for their potential as anti-Alzheimer's agents through in-vitro and in-vivo studies in appropriate animal models. To further understand their interaction with acetylcholinesterase enzyme (AChE), extra-precision docking, and molecular dynamics simulation studies were carried out. As the number of compounds was limited to thoroughly explore the structure-activity relationship, atom-based 3D-quantitative structure-activity relationships (QSAR) studies were carried out to get more insights. All the designed compounds were found to inhibit AChE with IC50 in the micromolar range. From pyrrolidone-2-one series, 6-chloro-N-(1-(1-(3,4-dimethoxybenzyl)-2-oxopyrrolidin-3-yl)piperidin-4-yl)pyridine-3-sulfonamide (9), 2-(1-benzylpiperidin-4-yl)-6,7-dimethoxy-4-(4-methoxyphenyl)quinoline (18) from quinoline series and N-(1-benzylpiperidin-4-yl)-2-(2-oxoindolin-3-yl)acetamide (23) from indolin-2-one series inhibited AChE with an IC50 value of 0.01µM. Based on other biochemical studies like lipid peroxidation, reduced glutathione, superoxide dismutase, catalase, nitrite, and behavioural studies (Morris water maze), compound 9 was found to be a potent AChE inhibitor which can be further explored as a lead molecule to design more potent and effective anti-Alzheimer's agents.

Optimization of the Extraction Process of Bioactive Compounds from Zingiber officinale Roscoe, Evaluation of Acetylcholinesterase Enzyme Inhibition and Cytotoxic Activity of the Free and Encapsulated Extract

The present study optimized the extraction process of bioactive compounds present in ginger (Zingiber officinale) dried at 80 °C, using ethanol:water 70:30 (v/v) as solvent. The extracts were evaluated for antioxidant activity by the 2,2’-azino-bis(3-ethylbenzothiazoline6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical reduction methods and by the chelating activity of FeII ions. It was found that the extraction condition with a temperature of 60 °C and an extraction time of 12 h showed better responses to the tests. Then, the characterization of the compounds was carried out by mass spectrometry and thermal analysis (thermogravimetric (TG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC)), identifying that the main compounds of ginger were gingerols and shogaols, being confirmed by the intensities and characteristics of the thermal graphs. The inhibition of the enzyme acetylcholinesterase (AChE) was evaluated using the Ellman test, which did not show an inhibitory action. Regarding cytotoxic activity, the free extract and encapsulated in liposomes were tested, showing antiproliferative effect at different concentrations for human kidney tumor cells (786-0), liver cells (HUH7.5), and Macaca mullata normal kidney cells (LLC-MK2). Given the results obtained, ginger presents itself as a renewable source of bioactive compounds and can be indicated for applications in the pharmaceutical industry

Larvicidal Activity of Ethanol Extract of Cinnamomum sintoc Blume Bark against Aedes aegypti: Role of the Extract as an Acetylcholinesterase Enzyme Inhibitor

The display ponders evaluated the larvicidal exercises of ethanol bark extricates of Cinnamomum sintoc BI against the third instar hatchlings of Aedes aegypti. For superior understanding, this show ponders moreover examined the instrument of plant extricates against the hatchlings through in silico examination. Larvicidal exercises of plant extricate were considered within the extent of 0.01 to 0.1% and two control bunch with aquades and temephos within the research facility bioassays against early third instar hatchlings of A. aegypti. The mortality was checked and subjected to probit investigation to decide the deadly concentrations (LC50 and LC90) to murder 50 and 90% of the treated hatchlings of the particular species. Also, to examine the instrument, four dynamic compounds within the plant extricate with the most noteworthy substance analyzed in silico with the acetylcholinesterase protein in A. aegypti. The appears about appear expanding the concentration will increment the passing of the hatchlings and the viability of the extricate is found to be superior to temephos. The comes about of in silico investigation appeared that the two dynamic compounds in plant extricates, specifically α-copaene and γ-muurolene have a component of activity comparable to temephos. Both of these compounds work as inhibitors of acetylcholinesterase chemicals. Our information recommends that the bark ethanol extricate of C. sintoc BI have the potential to be utilized as a larvicidal operator for the control of the A. aegypti.

In-vitro and in-silico cholinesterase inhibitory activity of bioactive molecules isolated from the leaves of Andrographis nallamalayana J.L. Ellis and roots of Andrographis beddomei C.B. Clarke

Cholinesterase inhibitors remain the best therapeutic strategies to treat Alzheimer's disease. In search for the potent and long-acting cholinesterase (AChE/BChE) inhibitors, we studied the inhibitory activities of three species of Andrographis genus viz, Andrographis paniculata (Burm.f.) Nees Andrographis nallamalayana J.L. Ellis , and Andrographis beddomei C.B. Clarke. It was demonstrated that the methanolic extract of these plants was able to inhibit acetylcholinesterase and butyrylcholinesterase. Furthermore, the phytochemical investigation led to the isolation of 11 known compounds. Echioidinin (1), skullcapflavone I (2), 5,2′,6′-trihydroxy-7-methoxyflavone (3), 5.,2′,6′-trihydroxy-7-methoxyflavone 2′-O-β-D-glucopyranoside (4), and chrysin 7-glucuronide (5) were isolated from leaves of A. nallamalayana whereas 7-O-methylwogonin (9), wogonin (10), viscidulin II (11), andrographidine C (12), andrographidine G (13), 5,8,2′-trihydroxy-7-methoxyflavone-5-O-ß-D glucopyranoside (14) were isolated from roots of A. beddomei. Their structures were elucidated by 1H, 13CNMR spectra, mass spectrometry, and X-ray single crystal diffraction experiments. The SC-XRD and Hirshfeld Surface analysis of eight flavonoids (Compound 1, 2, 4, 6, 9, 11, 12, 13 and positive control drug galantamine hydrobromide is reported for the first time. Compound 6, 4, 10, 9 were potent inhibitors of acetylcholinesterase enzyme with IC50 values of 1.86 ± 0.139 μM, 3.37 ± 0.086 μM, 6.38 ± 0.098 μM, 9.11 ± 0.116 μM respectively. Compound 6 was more potent than the positive control, galantamine (IC50 = 4.68 ± 0.032 μM). All these compounds showed moderate to weak inhibitory activity against BChE. In addition, molecular docking studies were performed to explore the binding mode of the compounds, and the results were in good agreement with the experimental results. These results clearly indicate the potential of these compounds as powerful lead molecules for further investigations.

Antioxidant, AChE inhibitory, and anticancer effects of Verbascum thapsus extract.

Verbascum thapsus (VT) is a medicinal plant that is used in folk medicine to treat a variety of ailments. For this study, the biological functions of VT methanol extract were determined in vitro. The plant's methanol extract was created through the maceration process. The phytochemical composition of plant extracts was investigated using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). The antioxidant capacity of the extract was determined using the DPPH (2,2-diphenyl-1-picrylhydrazil) and ABTS (2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) tests and its cytotoxicity was assessed using the MTT ((3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole)) assay on the Caco-2 (human colorectal adenocarcinoma cells), LNCaP (Lymph Node Carcinoma of the Prostate), and HEK293 cell lines (Human embryonic kidney 293 cells) used to model colon, prostate, and non-cancerous cells. VT extract showed low DPPH and ABTS radical scavenging activities compared to standard antioxidants at 30 mg/ml concentration. In addition, it was determined that VT extract inhibited acetylcholinesterase enzyme.

Hesperidin counteracts chlorpyrifos-induced neurotoxicity by regulating oxidative stress, inflammation, and apoptosis in rats.

Chlorpyrifos (CPF), considered one of the most potent organophosphates, causes a variety of human disorders including neurotoxicity. The current study was designed to evaluate the efficacy of hesperidin (HSP) in ameliorating CPF-induced neurotoxicity in rats. In the study, rats were treated with HSP (orally, 50 and 100mg/kg) 30min after giving CPF (orally, 6.75mg/kg) for 28 consecutive days. Molecular, biochemical, and histological methods were used to investigate cholinergic enzymes, oxidative stress, inflammation, and apoptosis in the brain tissue. CPF intoxication resulted in inhibition of acetylcholinesterase (AChE) and butrylcholinesterase (BChE) enzymes, reduced antioxidant status [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH)], and elevation of malondialdehyde (MDA) levels and carbonic anhydrase (CA) activities. CPF increased histopathological changes and immunohistochemical expressions of 8-OHdG in brain tissue. CPF also increased levels of glial fibrillary acidic protein (GFAP) and nuclear factor kappa B (NF-κB) while decreased levels of nuclear factor erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α). Furthermore, CPF increased mRNA transcript levels of caspase-3, Bax, PARP-1, and VEGF, which are associated with apoptosis and endothelial damage in rat brain tissues. HSP treatment was found to protect brain tissue by reducing CPF-induced neurotoxicity. Overall, this study supports that HSP can be used to reduce CPF-induced neurotoxicity.

Design, synthesis, in vitro acetylcholinesterase, butyrylcholinesterase activities, and in silico molecular docking study of oxindole-oxadiazole hybrid analogues

Alzheimer's disease is a neurological disorder characterized by cognitive dysfunction and deficits in activities of daily living. There is no drug available for Alzheimer's at the moment, and the inhibition of acetylcholinesterase and butyrylcholinesterase enzymes are a good target to treat Alzheimer's disease. In this study, a series of new oxindole-oxadiazole hybrid analogues (1–18) have been synthesized and evaluated for acetylcholinesterase and butyrylcholinesterase inhibitory activities. All compounds showed a varied degree of inhibition, ranging from 0.80 ± 0.20 to 12.50 ± 0.40 µM (against acetylcholinesterase) and 1.10 ± 0.20 to 20.30 ± 0.10 µM (against butyrylcholinesterase), as compared to the standard inhibitor donepezil (IC50 values of 2.16 ± 0.12 & 4.5 ± 0.11 µM, respectively). In the case of acetylcholinesterase, analogue 17 (IC50 = 0.80 ± 0.20 µM) while in case of butyrylcholinesterase, analogue 5 (IC50 = 1.10 ± 0.20 µM) was found the most potent among the whole series. Structure-activity relationship has been established for all compounds, which mainly depended upon the nature, number, position, and electron-donating or -withdrawing effect of the substituent(s) on the phenyl ring. A molecular docking study was carried out to investigate the interaction of the most potent compounds with the active site of enzymes. The stability of each drug-like hit in complex with acetylcholinesterase and butyrylcholinesterase was determined by computing their RMSD, RMSF analysis. Among all the compounds, compound 17 and compound 5 respectively, revealed a good interactions and stability during the entire simulation procedure.

"Cholinergic side Effect-Free anticancer drugs: paving the way for safer and more effective cancer treatment"

Cancer is a leading cause of mortality worldwide, and various anticancer medications have been developed that target different biological pathways involved in cancer growth and progression. Topoisomerase 1 (Top1) is an essential enzyme involved in unwinding supercoiled DNA, and it serves as a key target for several anti-cancer drugs. Irinotecan (FDA approved drug), a semi-synthetic camptothecin derivative, is an effective Top1 toxin that eliminates human cancer cells. Cancer patients suffer from the cholinergic syndrome caused by irinotecan and other Top1 inhibitors. Irinotecan-treated patients have developed cholinergic syndrome due to acetylcholinesterase (AChE) enzyme inhibition. It appears that irinotecan or its metabolites directly interact with AChE and inhibit its role of converting acetylcholine to choline, leading to an accumulation of acetylcholine and subsequent symptoms of the cholinergic syndrome. The phytochemicals present in Phyllanthus emblica, commonly referred to as amla, have been studied to determine their therapeutic effects. As an alternative treatment for cancer, this study explores the potential of phytochemicals found in amla to target and inhibit the Top1 protein. Additionally, the study aims to identify a non-inhibitor for AChE. Molecular docking studies assessed phytochemical binding affinities to Top1 and AChE enzymes, and ADME analyses were performed to assess their drug-likeness properties. Subsequently, molecular dynamic simulation was employed to assess the stability of these compounds. The results suggest that new anticancer medications that do not inhibit AChE or fresh Top1 inhibitors that use the camptothecin scaffold may alleviate some of the irinotecan’s side effects. Communicated by Ramaswamy H. Sarma

Synthesis and Cholinesterase Inhibitory Potency of 2,3-Indolo-oleanolic Acid and Some Related Derivatives

In this study, the synthesis and biological activities of previously and newly synthesized oleanolic acid derivatives containing seven-membered cyclic amines at the C28 position were described. The obtained compounds were fully characterized via 1H and 13C NMR spectroscopy, and the bioactivity was evaluated by Ellman’s method. Among the tested compounds, 2,3-indolo-oleanolic acid was found to be the most active compound with an IC50 value of 0.78 µM against acetylcholinesterase. These results are significant due to the fact that research on the inhibition of acetylcholinesterase and butyrylcholinesterase enzymes by oleanolic acid, in particular indoloderivatives, is limited.

Evaluation of bioactive compounds from Ficus carica L. leaf extracts via high-performance thin-layer chromatography combined with effect-directed analysis

This study compares different solvent systems with the use of spontaneous fermentation on the phytochemical composition of leaf extracts from a locally grown white variety of common fig (Ficus carica Linn.). The aim was to detect and identify bioactive compounds that are responsible for acetylcholinesterase (AChE), α-amylase and cyclooxygenase-1 (COX-1) enzyme inhibition, and compounds that exhibit antimicrobial activity. Bioactive zones in chromatograms were detected by combining High-performance thin-layer chromatography (HPTLC) with enzymatic and biological assays. A new experimental protocol for measuring the relative half-maximum inhibitory concentration (IC50) was designed to evaluate the potency of the extracts compared to the potency of known inhibitors. Although the IC50 of the fig leaf extract for α-amylase and AChE inhibition were significantly higher when compared to IC50 for acarbose and donepezil, the COX-1 inhibition by the extract (IC50 = 627 µg) was comparable to that of salicylic acid (IC50 = 557 µg), and antimicrobial activity of the extract (IC50 = 375–511 µg) was similar to ampicillin (IC50 = 495 µg). Four chromatographic zones exhibited bioactivity. Compounds from detected bioactive bands were provisionally identified by comparing the band positions to coeluted standards, and by Fourier transform infrared (FTIR) spectra from eluted zones. Flash chromatography was used to separate selected extract into fractions and isolate fractions that are rich in bioactive compounds for further characterisation with nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS) analysis.The main constituents identified were umbelliferon (zone 1), furocoumarins psoralen and bergapten (zone 2), different fatty acids (zone 3 and 4), and pentacyclic triterpenoids (calotropenyl acetate or lupeol) and stigmasterol (zone 4).

Evaluation of berberine nanoparticles as a strategy to modulate acetylcholinesterase activity

Researchers have concentrated efforts in the search for natural-based reversible inhibitors for cholinesterase enzymes as they may play a key role in the treatment of degenerative diseases. Diverse plant alkaloids can inhibit the action of acetylcholinesterase and, among them, berberine is a promising bioactive. However, berberine has poor water solubility and low bioavailability, which makes it difficult to use in treatment. The solid dispersion technique can improve the water affinity of hydrophobic substances, but berberine solid dispersions have not been extensively studied. Safety testing is also essential to ensure that the berberine-loaded solid dispersions are safe for use. This study investigated the effectiveness of berberine-loaded solid dispersions (SD) as inhibitors of acetylcholinesterase enzyme (AChE). Docking simulation was used to investigate the influence of berberine on AChE, and in vitro assays were conducted to confirm the enzymatic kinetics of AChE in the presence of berberine. Berberine SD also showed improved cytotoxic effects on tumoral cells when dispersed in aqueous media. In vivo assays using Allium cepa were implemented, and no cytotoxicity/genotoxicity was found for the berberine solid dispersion. These results suggest that berberine SD could be a significant step towards safe nanostructures for use in the treatment of neurodegenerative diseases.

Unveiling the phytochemical and pharmacological potential of Mimusops maxima (Poiret) Vaughan-an endemic plant with potential therapeutic effects

Mimusops maxima (Poiret) Vaughan is an endemic plant of Mauritius Island that has never been studied for neither its phytochemical nor pharmacological properties. Hence this study targeted to extract the phytochemicals using three different solvents and characterizion them through HPLC-MS-MS, alongside investigating their effects against chronic diseases. The methanolic extract beared the highest total phenolic and total flavonoid composition, (31.10 ± 0.25 gallic acid equivalents/gram (GAE/g) and 38.68 ± 0.34 rutin equivalent (mgRE/g)), respectively), succeeded by the ethyl acetate and aqueous extracts. The antioxidant assay demonstrated that the methanolic extract had the highest potency in terms of antioxidant potential. The most potent acetylcholinesterase enzyme inhibitor was the ethyl acetate extract (4.78 ± 0.28 mg GALAE/g) followed by the methanolic extract (4.48 ± 0.05 mgGALAE/g). The most inhibition of the tyrosinase enzyme was generated by the methanolic extract (122.53 ± 2.72 mg KAE/g),the ethyl acetate extract and aqueous extracts (113.96 ± 1.53 and 6.19 ± 0.30 mg KAE/g, respectively) followed and were behind the methanolic extract. The methanolic and ethyl acetate extracts can be formulated as tissanes and extracts as health supplements as a prophylaxis measure for non-communicable diseases pending further toxicological investigations.

Determination of cytotoxic, anti-acetylcholinesterase and antioxidant activity of some medicinal Artemisia spp.

The study aims to investigated the antioxidant activities, phenolic compounds, acetylcholinesterase enzyme inhbition and cytotoxic effects of two different of Artemisia spp. (Artemisia dracunculus L. and Artemisia dracunculoides Pursh) cultivated in Turkey organically, for the first time. Total phenolic, total flavonoid contents of the plants determined spectrophotometrically while antioxidant activity DPPH, CUPRAC, and FRAP was determined using colorimetric method. And also acetylcholinesterase enzyme inhibition activity and anti-cancer activity in-vitro aganist human melanoma (VMM917, CRL-3232), lung carcinoma (A549, CCL-185) and, normal human fibroblast (hGF, PCS-201-018) cells were studied. Total phenolic (225-324 mgGAE/g sample) and total flavonoid contents (0.066-0.085 mgQAE/g sample), antioxidant activity (DPPH (1.371-1.655 mg/mL), CUPRAC (0.246-0.344 µM CTEAC) and FRAP (462.133-726.661 µM CTEAC)). A. dracunculus and A. dracunculoides extracts inhibited 40.09±0.65%, and 39.48±3.68% of acetylcholinesterase activity. It was determined that demonstrated the selective effect of A. dracunculus and A. dracunculoides on the cytotoxicity of A549 and hGF cells.