Anticholinesterase Properties Research Articles

A Comprehensive Exploration of the Multifaceted Neuroprotective Role of Cannabinoids in Alzheimer's Disease across a Decade of Research.

Alzheimer's disease (AD), a progressive neurodegenerative disorder, manifests through dysregulation of brain function and subsequent loss of bodily control, attributed to β-amyloid plaque deposition and TAU protein hyperphosphorylation and aggregation, leading to neuronal death. Concurrently, similar cannabinoids to the ones derived from Cannabis sativa are present in the endocannabinoid system, acting through receptors CB1R and CB2R and other related receptors such as Trpv-1 and GPR-55, and are being extensively investigated for AD therapy. Given the limited efficacy and adverse effects of current available treatments, alternative approaches are crucial. Therefore, this review aims to identify effective natural and synthetic cannabinoids and elucidate their beneficial actions for AD treatment. PubMed and Scopus databases were queried (2014-2024) using keywords such as "Alzheimer's disease" and "cannabinoids". The majority of natural (Δ9-THC, CBD, AEA, etc.) and synthetic (JWH-133, WIN55,212-2, CP55-940, etc.) cannabinoids included showed promise in improving memory, cognition, and behavioral symptoms, potentially via pathways involving antioxidant effects of selective CB1R agonists (such as the BDNF/TrkB/Akt pathway) and immunomodulatory effects of selective CB2R agonists (TLR4/NF-κB p65 pathway). Combining anticholinesterase properties with a cannabinoid moiety may enhance therapeutic responses, addressing cholinergic deficits of AD brains. Thus, the positive outcomes of the vast majority of studies discussed support further advancing cannabinoids in clinical trials for AD treatment.

Novel Study on Chemical Characterization and Antimicrobial, Antioxidant, and Anticholinesterase Activity of Essential Oil from Ecuadorian Bryophyte Syzygiella rubricaulis (Nees) Stephani.

Our research focuses on exploring the chemical composition and some biological properties of the essential oil derived from Syzygiella rubricaulis (Nees) Stephani, a bryophyte species. To conduct a comprehensive analysis, we utilized a DB5MS capillary column along with gas chromatography coupled to mass spectrometry (GC-MS) and flame ionization (GC-FID). The qualitative and quantitative examination revealed the presence of 50 compounds, with hydrocarbon sesquiterpenes (48.35%) and oxygenated sesquiterpenes (46.89%) being the predominant constituents. Noteworthy compounds identified include bicyclogermacrene (12.004%), cedranone <5-> (9.034%), spathulenol (6.835%), viridiflorol (6.334%), silphiperfol-5,7(14)-diene (6.216%), biotol <β-> (6.075%), guaiol (4.607%), viridiflorene (4.65%), and α-guaienol (3.883%). Furthermore, we assessed the antimicrobial, antioxidant, and anticholinesterase activity of the essential oil, revealing a compelling inhibitory effect against acetylcholinesterase (AChE) with an IC50 value of 26.75 ± 1.03 µg/mL and a moderate antimicrobial (MIC 500 µg/mL, Enterococcus faecium, Lysteria monocytogenes) and antioxidant effect (ABTS: SC50 343.38 and DPPH 2650.23 µg/mL). These findings suggest the potential therapeutic application of the bryophyte essential oil in the treatment of Alzheimer's disease due to its potent anticholinesterase properties.

Phytochemistry, Bioactivity, and Ethnopharmacology of the Genus Lepechinia Willd. (Lamiaceae): A Review.

The genus Lepechinia (Lamiaceae) involves several aromatic shrubs that are distributed only in the American continent, inhabiting mountain areas, mainly in the Andean region of South America. Based on the PRISMA approach, we selected and critically analyzed 48 research articles. From a phytochemical point of view, most of the secondary metabolites reported in Lepechinia spp. are terpenes and terpenoids, with a few exceptions comprising flavonoids and other shikimic acid derivatives. On the one hand, sesquiterpenoids of the guajane, aromadendrane, eudesmane, and cadinane groups are characteristic of essential oils, together with (E)-β-caryophyllene as the main representative of its chemical family. On the other hand, abietane diterpenoids are the prevalent compounds described in non-volatile fractions. Many biological activities and traditional medical uses have been reported for both pure metabolites and complex mixtures (e.g., essential oils). Regarding ethno-medical uses, the treatment of muscle pain, headache, toothache, diabetes mellitus, uterine tumors, uterine infections, and diarrhea has been reported. Concerning their verified biological activities, insecticidal, antifungal, antioxidant, and anticholinesterase properties have been described. Furthermore, some data concerning anti-herpetic activity have been reported.

CHALCONE ANALOGUES AS POTENTIAL MEDICINES OF PATHOGENETIC THERAPY OF ALZHEIMER'S DISEASE: IN VITRO SCREENING

Introduction. Alzheimer's disease is one of the most common forms of dementia, the pathogenesis of which is based on the accumulation of β–amyloid plaques in brain structures and the development of cholinergic deficiency. The aim of the study was to evaluate the effect of chalcone analogues on the change in acetylcholinesterase activity and the process of β-amyloid aggregation in vitro. Material and methods. The tested compounds were six bis-substituted chalcone analogues, which were dissolved in dimethylsulfoxide during the analysis to obtain double dilutions. The effect of the studied substances on the activity of acetylcholinesterase was evaluated by the modified Ellman method. The change in the aggregation process of β-amyloid particles was determined in reaction with congo red after 3, 6 and 9 days of incubation. Based on the obtained results of the «% inhibition- concentration» relationships, the IC50 index was calculated, which was expressed in mmol/ml. Results. In the course of the study, it was shown that the analyzed chalcone analogues inhibit the aggregation of β-amyloid particles starting from the 6th day of incubation with a maximum on the 9th day. At the same time, the compounds that showed the highest level of activity were trimethoxy-substituted substances under the codes AZBAX4 and AZBAX6, whose IC50 on the 9th day of the study was 21.4±0.928 mmol/ml and 32.4±0.456 mmol/ml, respectively. Also, a high level of anticholinesterase properties was established for these compounds with IC50 of 35.9±0.991mmol/ml and 25.1±0.261 mmol/ml, respectively. The rest of the tested compounds showed a lower level of activity. Conclusion. The study showed that chalcone analogues under the codes AZBAX4 and AZBAX6 inhibit the activity of acetylcholinesterase and the pro-cess of aggregation of β-amyloid in vitro, which makes these compounds promising for further study in order to develop medicines for the pathogenet-ic treatment of Alzheimer's disease.

Metabolomic Analysis and in Vitro Investigation of the Biological Properties of a By-Product Derived from Vicia faba.

By-products from plant sources are recently regarded as a valuable source of bioactive compounds. In this regard, the present study aims to assess the bioactivities of the 70 % MeOH extract obtained from Vicia faba peels and analyze its metabolomic profile. Acetylcholinesterase and carbohydrate metabolizing enzymes inhibitory activities of the plant extract were assayed using quantitative colorimetric tests. Antioxidant activity was estimated by DPPH assay, and cytotoxic activity was evaluated against normal fibroblast skin cells (1-BJ1). Ninety-one metabolites were tentatively identified using ultra-high-performance liquid chromatography (UHPLC) hyphenated with quadrupole-time-of-flight tandem mass spectrometry (QTOF-MS). Most of these compounds were described for the first time in the plant. In addition, catechin, rutin, quercitrin, and rhamnetin were isolated from the plant extract. The plant extract and the isolated compounds possessed no cytotoxic activity on (1-BJ1), while they exhibited anticholinesterase with the highest activity for 70 % MeOH extract (IC50 =120.11 mg/L), antioxidant potential with the highest activity for rutin (90.54±0.73 %), and carbohydrate metabolizing inhibitory activities with the highest activity for rutin. These discoveries imply that V. faba peels might serve as an efficient antioxidant, exhibit anticholinesterase properties, and have the potential for use in managing diabetes, all while avoiding cytotoxicity in normal cells.

Nutritional, Antioxidant, Antimicrobial, and Anticholinesterase Properties of Phyllanthus emblica: A Study Supported by Spectroscopic and Computational Investigations.

Dietary fruits and vegetables play a vital role as food and drugs and are the main sources of antioxidant defences against degenerative diseases, such as brain dysfunctions, cardiovascular diseases, immune system deteriorations, and cancers, brought on by oxidative damage. Phyllanthus emblica is a significant herbal remedy used in conventional medicine to recover lost strength and power. In this research, the potential value of Phyllanthus emblica as a food and drug is researched. The total phenolic, total flavonoid, and total tannin contents as well as the nutritional value, vitamin C, vitamin E, and mineral contents of different organs of P. emblica were evaluated. The antioxidant and antimicrobial activities of extracts and fractions of different organs of P. emblica were determined. A total of eleven flavonoids, simple phenolic, tannin-related phenolic, and tannin molecules were isolated from a hydroalcoholic extract of the leaves and fruits. The structures were identified by spectroscopic data and comparison with the literature values as gallic acid (1), naringenin 7-O-(6″-O-galloyl)-β-D-glucopyranoside (2), 3,3'-di-O-methyl ellagic acid-4'-O-β-d-glucopyranoside (3), 1-O-galloyl glycerol (4), 1,6-di-O-galloyl-β-d-glucopyranoside (5), flavogallonic acid bislactone (6), corilagin (7), ethyl gallate (8), urolithin M5 (9), (E)-p-coumaroyl-1-O-β-d-glucopyranoside (10), and 1,2,4,6-tetra-O-galloyl-β-d-glucopyranoside (11). Among them, compounds 3 and 10 are first isolated from the plant. Molecular docking was performed to investigate the comparative interactions between positive controls (galantamine and donepezil) and selected compounds utilizing acetylcholinesterase (4EY7) as a target receptor. Results exhibited the potency of these compounds against the target receptor. In summary, P. emblica has a wealth of minerals, vitamins C and E, and polyphenolic phytochemicals that may work together to treat infectious disease, prevent and/or treat oxidative-damage-related illnesses including Alzheimer's disease.

Linking traditional medicine to modern phytotherapy: Chemical characterization and assessment of antioxidant and anticholinesterase effects in vitro of a natural Persian remedy for dementia

Several natural remedies are used in the Traditional Persian Medicine (TPM) to prevent dementia, but their efficacy is debated. In this work, an improved “Safoof-e-Nesyān” formulation described in the “Qarābādin-e-Azam” pharmacopoeia was developed, and its chemical composition and antioxidant and anti-cholinesterase properties were assessed. The formulation contains a mixture (FM) of Cinnamomum cassia (CC), C. verum (CV), Pistacia lentiscus (PL), Rheum palmatum (RP), Syzygium aromaticum (SA), and Zingiber officinalis (ZO) powdered plants. Its total phenolic content is 110.45 mg GAE/g, while the total flavonoid content is 6.28 mg RE/g. 66 secondary metabolites (mainly tannins, flavonoids, anthraquinones, and gingerols) were identified by UPLC-QToF-MS analysis. FM exerts antioxidant effects by scavenging radicals, and by reducing and chelating metals such as Mb, Cu and Fe. The anticholinesterase activity of one gram of the FM equals that of 3.60 mg of the reference drug galantamine, on both acetyl- and butyryl-cholinesterase. Correlations between specific compounds and bioactivities were highlighted by multivariate analysis of data: lyoniresinol 9′-glucoside strongly correlates with antiradical activities on DPPH and ABTS and reducing activity on Cu, and with anti-AChE effects. Most of the identified flavonoids and the ellagic acid derivatives positively correlate with the reducing activity on Fe and Mb, and with anti-BChE effects. Finally, a tablet formulation of the FM was developed, and its physical properties were preliminarily assessed. Overall, our results indicate that the FM may be a useful natural remedy for dementia, although further safety and efficacy assessments in vivo are required.

Benzimidazole-Carboxamides as Potential Therapeutics for Alzheimer's Disease: Primary Analysis In Silico and In Vitro.

A primary in vitro analysis of the anticholinesterase properties of substituted 1,3-dihydro-2-oxo-1H-benzimidazol-2-ones was performed along with in silico calculation of their oral toxicity. These compounds are analogs of BIMU-8, a well-known agonist of serotonin 5-HT4 receptors, and are supposed to combine the functions of cholinesterase inhibitors and serotonin receptor agonists. Biochemical analysis showed the ability of the obtained chemicals to inhibit acetyl- and butyrylcholinesterase. A compound with minimal toxicity, high inhibitory ability against butyrylcholinesterase, and low inhibitory ability against acetylcholinesterase has been identified, which is of greatest interest for further experimental development.

Synthesis, anticholinesterase and anti-radical activity of 2,3,5-trisubstituted 4&lt;i&gt;H&lt;/i&gt;-imidazol-4-ones, green fluorescent protein chromophore analogues

The one-pot synthesis of N -substituted α,β-dehydrotyrosyl dipeptides was carried out by the azlactone method. The target dipeptides were obtained in good yields (53-79%). From the latter, 2,3,5-trisubstituted 4-imidazolones were obtained using 1,1,1,3,3,3-hexamethyldisilazane as a dehydrating agent. It was found that in the case of β-alanine-containing peptides, abstraction of the methyl ester of acrylic acid and the formation of 2,5-disubstituted 4-imidazoline were observed. Antiradical and anticholinesterase properties of the synthesized compounds were studied. Docking analysis was carried out for both some dipeptides and imidazole-4-ones.

Antioxidant and Anticholinesterase Potentials of Novel 4,6-Dimethoxyindole based Unsymmetrical Azines: Synthesis, Molecular Modeling, In Silico ADME Prediction and Biological Evaluations

Chemically and biologically important -C = N-N = C- diimine linkage was used to build unsymmetrical azine systems with indole heterocyclic backbone and substituted aromatic carbaldehydes. Ten novel compounds 7a-j were synthesized by the Schiff base reaction of 4,6-dimethoxyindole-7-hydrazone 5 and a range of substituted carbaldehydes 6a-j with high yields and purities. The biological study was directed to identify the antioxidant potentials due to the expected electronic delocalization capability of designated linkage which is important for possible hydrogen or electron donation. The three different assays, namely DPPH free radical scavenging, ABTS cationic radical decolarization and CUPRAC (cupric reducing antioxidant capacity) were employed to detect the antioxidant properties. The antioxidant potentials were found to be moderate for ABTS and CUPRAC assays and the compound 7j was the most potent candidate for all the antioxidant assays. More importantly, the anticholinesterase properties were investigated by acetylcholinesterase (ACh) and butyrylcholinesterase (BCh) enzyme inhibition assays. The molecular docking studies were also carried out to determine the possible poses of ligands 7a-j in binding sites of enzymes and ligand-residue interactions. The synthesized compounds were found to be more effective for the anticholinesterase activity with three promising candidates 7d, 7h and 7j in the case of BChE inhibitions. The compound 7h was determined as the best candidate with the comparable IC50 values for AChE and better inhibition potency for BChE with 7j. A range of hydrophobic and hydrophilic interactions were detected for the designated compound 7h and 7j through different amino acid residues and the computational results were found to be compatible with the biological counterparts.

Biological Activities and Chemical Composition of Essential Oil from Hedyosmum purpurascens (Todzia)—An Endemic Plant in Ecuador

Hedyosmum purpurascens is an endemic species found in the Andes of Ecuador and it is characterized by its pleasant smell. In this study, essential oil (EO) from H. purpurascens was obtained by the hydro-distillation method with a Clevenger-type apparatus. The identification of the chemical composition was carried out by GC-MS and GC-FID in two capillary columns, DB-5ms and HP-INNOWax. A total of 90 compounds were identified, representing more than 98% of the total chemical composition. Germacrene-D, ϒ-terpinene, α-phellandrene, sabinene, O-cymene, 1,8-cineole and α-pinene accounted for more than 59% of the EO composition. The enantioselective analysis of the EO revealed the occurrence of (+)-α-pinene as a pure enantiomer; in addition, four pairs of enantiomers were found (α-phellandrene, o-cymene, limonene and myrcene). The biological activity against microbiological strains and antioxidants and the anticholinesterase properties were also evaluated and the EO showed a moderate anticholinesterase and antioxidant effect, with an IC50 value of 95.62 ± 1.03 µg/mL and a SC50 value of 56.38 ± 1.96. A poor antimicrobial effect was observed for all the strains, with MIC values over 1000 µg/mL. Based on our results, the H. purpurasens EO presented remarkable antioxidant and AChE activities. Despite these promising results, further research seems essential to validate the safety of this medicinal species as a function of dose and time. Experimental studies on the mechanisms of action are essential to validate its pharmacological properties.

Memory-Enhancing and Antioxidant Activities of the Hydroethanolic Leave Extract of Piliostigma reticulatum (Fabaceae) in the Monosodium Glutamate-Induced Alzheimer's Disease Model

Background: Piliostigma reticulatum (Fabaceae) is a plant used in Cameroon for the treatment of madness and migraine. Aims and Objectives: This study aims to evaluate the memory-enhancing and antioxidant activities of the hydroethanolic leaves extract of PR in the monosodium glutamate-induced Alzheimer's disease model. Materials and Methods: The Y-maze, Radial-arm maze and Novel object recognition tests were used to assess short, and long-term memory. At the end of the experiments, the brains of mice were scavenged for biochemical and histological analysis. Results: It was observed that the hydroalcoholic extract of PR leaf significantly reversed the percentage of spontaneous alternation compared to the negative control group at the different doses tested (p&lt;0.01; p&lt;0.001) in the Y-maze test. In the radial arm maze test, the extract significantly (p&lt;0.001) reduced the time spent consuming the bait, the number of reference memory and working memory errors at all doses. The treatment of animals with hydroethanolic extract of PR resulted in a significant increase in the discrimination index (p&lt;0.001) in the unfamiliar object recognition test. In addition, the extract significantly (p &lt; 0.01); p &lt; 0.001) decreased acetylcholinesterase activity,and MDA levels at all tested doses; and significantly (p &lt; 0.05; p &lt; 0.001) increased SOD level and Catalase activity in comparison to the negative control group. The histological analysis showed that the extract of Piliostigma reticulatum protected the different structures of the hippocampus against damage caused by monosodium glutamate. Conclusion : The memoryenhancing induced by the hydroethanolic leaves extract of Piliostigma reticulatum could be due to his antioxidant and anticholinesterase properties. These effects could justify the use of this plant to manage nervous system affections.

Sea cucumber (Holothuria atra) ethyl-acetate extract exerts anti-cholinesterase properties

Sea cucumber (Holothuria atra) ethyl-acetate extract exerts anti-cholinesterase properties

Selenium-Derivative Compounds: A Review of New Perspectives in the Treatment of Alzheimer's Disease.

Alzheimer's disease (AD) is one of the most prevalent types of dementia, affecting millions of older people worldwide. AD is stimulating efforts to develop novel molecules targeting its main features associated with a decrease in acetylcholine levels, an increase in oxidative stress and depositions of amyloid-β (Aβ) and tau protein. In this regard, selenium-containing compounds have been demonstrated as potential multi-targeted compounds in the treatment of AD. These compounds are known for their antioxidant and anticholinesterase properties, causing a decrease in Aβ aggregation. In this review, we approach structure-activity relationships of each compound, associating the decrease of ROS activity, an increase of tau-like activity and inhibition of AChE with a decrease in the self-aggregation of Aβ. We also verify that the molecular descriptors apol, nHBAcc and MlogP may be related to optimized pharmacokinetic properties for anti-AD drugs. In our analysis, few selenium-derived compounds presented similar molecular features to FDA-approved drugs. We suggest that unknown selenium-derived molecules with apol, nHBAcc and MlogP like FDA-approved drugs may be better successes with optimized pharmacokinetic properties in future studies in AD.

Chemical Profiling of Hedyosmum cumbalense and Hedyosmum spectabile (Chloranthaceae) Essential Oils, and Their Antimicrobial, Antioxidant, and Anticholinesterase Properties

In Ecuador, Hedyosmum cumbalense and Hedyosmum spectabile are valued for their well-known aromatic characteristics and therapeutic benefits. In this study, fresh and dried leaves of these species were steam-distilled to obtain their essential oils (EOs) for chemical characterization and assessment of their antimicrobial, antioxidant, and anticholinesterase properties. Gas chromatography coupled to mass spectrometry (GC-MS) and a flame-ionized detector (GC-FID) with a nonpolar column was employed to determine the chemical composition, along with the enantioselective analysis. The antimicrobial activity was evaluated against three Gram-positive, two Gram-negative, and two sporulated fungi. The radical scavenging properties were evaluated by DPPH and ABTS assays. A total of 66 and 57 compounds were identified for H. cumbalense and H. spectabile, respectively. Two pairs of enantiomers for each species were also detected, with (1R,5R)-(+)-sabinene and (1S,5S)-(-)-sabinene found in both specimens. A poor effect against Gram-positive cocci was observed on H. cumbalense (MIC of 4000 µg/mL). Both oils displayed weak antifungal activities, exhibiting a MIC of 1000 µg/mL. H. cumbalense had a good scavenging effect assessed by the ABTS radical (SC50 = 96.02 ± 0.33 µg/mL). Both EOs showed a strong anticholinesterase potential with an IC50 value of 61.94 ± 1.04 µg/mL for H. cumbalense and 21.15 ± 1.03 µg/mL for H. spectabile.

Synthesis of deoxy-Andrographolide Triazolyl Glycoconjugates for the Treatment of Alzheimer's Disease.

A new andrographolide-based terminal alkyne 3 was synthesized in good yield from deoxy-andrographolide 2, obtained from a natural compound andrographolide 1, which in turn was isolated from the leaves of the plant Andrographis paniculata. Copper(I)-catalyzed azide-alkyne cycloaddition reaction of alkyne 3 with azido-sugars 4a-f furnished a library of andrographolide-fastened triazolyl glycoconjugates 5a-f in good yields. The structures of these semisynthetic andrographolide derivatives were established by Fourier transform infrared, NMR, and mass spectroscopy. The compounds 5a-f were further evaluated against Alzheimer's disease (AD) using a scopolamine (SCOP)-induced memory impairment mice model. It was observed that antioxidant and anticholinesterase properties of these compounds contribute significantly toward their remarkable potential to improve cognitive functioning.

Neuroprotective (Antioxidant, Antiamyloidogenic, and Antiexcitatory) Effects of Trévo&lt;sup&gt;TM&lt;/sup&gt; against Cadmium Chloride Neurotoxicity in Adult Male Wistar Rats

Cadmium (Cd) is a heavy metal that is deleterious to brain development as it increases brain aging. Trévo is a multi-herbal supplement that provides various health benefits, including boosting the immune system and detoxification. In this study, we investigated the neuroprotective effects of Trévo against the neurotoxic effects of cadmium chloride (CdCl&lt;sub&gt;2&lt;/sub&gt;). Thirty male Wistar rats were equally divided into three groups: Group I (normal control), Group II (administered CdCl&lt;sub&gt;2&lt;/sub&gt;), and Group III (administered Trévo and CdCl&lt;sub&gt;2&lt;/sub&gt;), and were used in the experiments. Animals were pretreated with 2 mL/kg of Trévo for five days and injected with Cd intraperitoneally 3 h later. Cd significantly increased the production of malondialdehyde (MDA), amyloidogenesis, activation of caspase 3 and 9, and the production of p53 and glutamate. It also inhibited the activity of Na&lt;sup&gt;+&lt;/sup&gt;/K&lt;sup&gt;+&lt;/sup&gt; ATPase, glutamate dehydrogenase, catalase, superoxide dismutase, and glutathione-S-transferase. The administration of Trévo revealed its antioxidant, anti-amyloidogenic, anti-excitotoxicity, and anticholinesterase properties as it prevented the biochemical changes induced by Cd toxicity in the brain of male Wistar rats. Our results supported the reported health benefits of Trévo as a good dietary supplement in preventing the toxic effects of poisonous substances, such as cadmium.

Phytochemicals from African eggplants (Solanum macrocarpon L) and Black nightshade (Solanum nigrum L) leaves as acetylcholinesterase inhibitors: an in-silico study

Acetylcholinesterase inhibitors (AChEIs) like donepezil are commonly used to treat Alzheimer’s disease. AChEIs have also been considered for other therapeutic uses, such as anti-inflammatory neuroprotective agents. Consequently, the use of natural plant products as potential AChEIs can have therapeutic benefits. We previously reported the anticholinesterase properties of the phenolics and alkaloids found in the leaf extracts of two tropical plants with nutritional and ethnobotanical importance—African eggplant (Solanum macrocarpon L) and Black nightshade (Solanum nigrum L). Here, we tested the ability of both extracts to inhibit human erythrocyte AChE (an indirect mediator of pro-inflammatory cytokines production via acetylcholine degradation). We further used molecular docking and MD simulation to identify the potential molecular mechanism(s) of phenolic and alkaloid compounds as human AChEIs. Special focus was given to compounds containing the benzyl group that can establish stacking interactions similar to donepezil (a standard AChEI). Flavone-luteolin rutinosides (LR) were identified as single-binding or dual-binding AChEIs; specifically, we attributed the dual-binding LR4 and LR5 to their linked hexose moiety. This characteristic allows the dual binders to occupy the catalytic triads and the peripheral anionic subsite, while exploring the catalytic gorge. We further delineated the inhibition of human erythrocyte AChE, as the flavone common to both plant extracts—luteolin rutinosides—had positive in silico interactions with AChE. These findings suggest that phytochemicals from S. macrocarpon and S. nigrum with dual binding properties can be potential AChE inhibitors. In fact, compounds such as LR4 and LR5 should be further investigated as potential inhibitors of human AChE and may represent important natural alternatives to donepezil. Communicated by Ramaswamy H. Sarma

In vitro Antioxidant and Anticholinesterase Activities of Extracts from the Leaves of Cassia moschata Kunth

Alzheimer’s disease (AD) is a neurodegenerative disorder, which is the most common cause of dementia. This disease commonly occurs in elderly people. The increase in life expectancy means that that the number of people suffering from AD is expected to rise each year if there is no effective treatment found. The relation of cholinesterase and oxidative stress to Alzheimer’s disease has been reported. In our previous study, we have investigated the potency of the ethanolic extract of Cassia moschata leaves as an anticholinesterase. The current study aimed to investigate the antioxidant and anticholinesterase properties of the ethanolic and aqueous extracts of C. moschata as well as to determine the total phenolic content (TPC). Two different methods were used to evaluate the antioxidant activity by 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The anticholinesterase assay was carried out against acetylcholinesterase (AChE) according to the modified Ellman’s method. The TPC was determined by a colorimetric method using Folin-Ciocalteu’s phenol reagent, and employing gallic acid as a reference. The ethanolic and aqueous extracts of C. moschata demonstrated antioxidant activity in both DPPH and ABTS assays. There were statistically significant differences in the IC50 values of the ethanolic and aqueous extracts in both DPPH and ABTS assays. The aqueous extract exhibited a lower IC50 value compared to the ethanolic extract. The IC50 value for the aqueous extract was 36.46 µg/mL in the DPPH assay, and 10.61 µg/mL in the ABTS method compared to IC50 38.74 µg/mL and 17.17 µg/mL for the ethanolic extract, respectively. Meanwhile, the ethanolic extract showed higher potency as anticholinesterase with the IC50 value of 44.43 µg/mL compared to the aqueous extract with an IC50 value of 114.60 µg/mL. The TPC measurement revealed that the aqueous extract has a higher amount of phenolic than the ethanolic extract. These data suggest that the aqueous extract from the leaves of C. moschata has a higher ability to scavenge free radicals compared to the ethanolic extract, which also contains a higher amount of phenolic compounds. However, the high content of phenolic compounds in the aqueous extract did not correspond to the anticholinesterase activity. The presence of non-phenolic compounds may also contribute to the anticholinesterase activity in the ethanolic extract.

Antioxidant and Anticholinesterase Properties of the Aqueous Extract of Balanites aegyptiaca L. Delile Fruit Pulp on Monosodium Glutamate-Induced Excitotoxicity in Swiss Mice.

Balanites aegyptiaca L. Delile (B. aegyptiaca) is used in traditional medicine for the treatment of memory impairment. This work aims to evaluate the antioxidant and anticholinesterase potential of BA fruit pulp extract on excitotoxicity induced by monosodium glutamate (MSG). MSG was administered 30 minutes after treatment with B. aegyptiaca aqueous fruit pulp extract (50, 125, 250, and 500 mg/kg) and vitamin C (100 mg/kg) for 30 days. The negative control group received only MSG, while the control group was given distilled water daily. Behavioral tests parameters (using the novel object recognition, Y-maze, and Barnes maze tests), oxidative stress biomarkers (malondialdehyde, superoxide dismutase, and catalase), nitric oxide, and acetylcholinesterase activity and hippocampal architecture were evaluated. Results obtained revealed that different doses of B. aegyptiaca significantly reversed the deleterious effect of MSG on memory. This was displayed by a significant (p < 0.05) increment in the percentage of spontaneous alternation in the Y-maze test and a significant (p < 0.001) increase in discrimination index in novel object recognition observed with 500 mg/kg extract dose. Moreover, the extract (250 and 500 mg/kg doses) significantly (p < 0.001) increased direct search strategy and significantly decreased (p < 0.01) the time taken to find the target hole in the Barnes maze. A modulation of hyperactivity was observed after administration of all extract doses compared to the negative control group in the open arena. Furthermore, the highest dose of the extract caused a significant (p < 0.001) improvement in antioxidant enzymes activity, associated with a significant (p < 0.001) decrement in nitric oxide and malondialdehyde concentrations and a significant (p < 0.01) decrease in acetylcholinesterase activity. Treatment with the extract also restored normal hippocampal cell architecture. B. aegyptiaca fruit pulp extract could thus confer neuroprotection through its antioxidant and anticholinesterase potential.