Anticholinesterase Activities of Selected Polyphenols – a Short Report

Algerian Prickly Pear Seed By-Products: Fatty Acids Composition, Antioxidant, Enzyme Inhibitory Activities towards Tyrosinase, Urease, α-Amylase, and Cholinesterase, along with the Ability to Protect from Thermal Protein Denaturation

Prickly pear seed is a source of the most expensive oil in the world, which is rich in vitamins and polyunsaturated fatty acids. Its extraction generates a large quantity of press cake. These two by-products need to be valued. The current study aimed to assess the fatty acid composition of oil and the phytochemical composition of press cake. In addition, the antioxidant and the inhibition of thermal protein denaturation effects of both Algerian seed by-products were evaluated with their inhibitory action against the activities of urease, tyrosinase, α-amylase, and cholinesterase enzymes. The GC MS analysis result revealed the richness of our oil in linoleic (74%) and palmitic (13%) acids methyl esters, respectively. The chemical composition of press cake was characterized by a high value of dry matter (94.94 ± 0.05%), especially the carbohydrates (85.13 ± 0.94%). The results of antioxidant activity presented by IC50 and A0.5 ranged from 7.51 ± 0.03 to 88.10 ± 0.92 µg/mL. Furthermore, the IC50 values were 40.19 ± 1.21 and 61.18 ± 0.03 µg/mL in thermal protein denaturation assay, and ranging from 22.97 ± 0.72 to 385.99 ± 0.27 µg/mL for the inhibition of enzymatic activities. These results indicate that the studied oil can be one of the strongest oils for its impressive effects and also encourage us to reuse its press cake in feed livestock.

Enzyme Inhibitory Activities, Phenolic Profile, and In Silico Studies of Sorbus torminalis Tree Bark Methanol Extract

The different parts of Sorbus torminalis (L.) Crantz are used in traditional medicine for various conditions such as cardiac diseases, cough, and diabetes, indicating its significant medicinal potential. Therefore, the current investigation aimed to reveal the phenolic composition of the poorly studied S. torminalis methanol extract of the bark, as well as its capacity to inhibit enzymes relevant to cardiovascular, neurodegenerative, and metabolic diseases. A total of 28 phenolic components, including 20 procyanidins aglycones (A- and B-type), four procyanidin glycosides, catechin and its glycoside, and two (epi)catechin derivatives, were detected using LC-MS. The contents of total polyphenols (6.22 %), total tannins (3.04 %), condensed tannins (0.70 %), and total flavonoids (0.24 %) were determined spectrophotometrically, highlighting the considerable phenolic richness of the examined plant material. The concentration-dependent ability to inhibit α-amylase (IC50=130 μg /mL), α-glucosidase (IC50=312.13 μg /mL), acetylcholinesterase (IC50=156.46 μg /mL), butyrylcholinesterase (IC50=217.68 μg /mL), and angiotensin-converting enzyme (IC50=36.77 μg /mL) was demonstrated in vitro. The in silico approach showed that catechin, procyanidin B2 and C1, S. torminalis bark constituents, can form stable complexes with the target enzymes but with different binding affinity. The results supported the medicinal potential of S. torminalis bark and significantly expanded our knowledge of its chemistry, justifying further research.

Advantages of Spray Drying over Freeze Drying: A Comparative Analysis of Lonicera caerulea L. Juice Powders-Matrix Diversity and Bioactive Response

The study investigated the impact of Lonicera caerulea L. juice matrix modification and drying techniques on powder characteristics. The evaluation encompassed phenolics (514.7-4388.7 mg/100 g dry matter), iridoids (up to 337.5 mg/100 g dry matter), antioxidant and antiglycation capacity, as well as anti-ageing properties of powders produced using maltodextrin, inulin, trehalose, and palatinose with a pioneering role as a carrier. Spray drying proved to be competitive with freeze drying for powder quality. Carrier application influenced the fruit powder properties. Trehalose protected the phenolics in the juice extract products, whereas maltodextrin showed protective effect in the juice powders. The concentrations of iridoids were influenced by the matrix type and drying technique. Antiglycation capacity was more affected by the carrier type in juice powders than in extract products. However, with carrier addition, the latter showed approximately 12-fold higher selectivity for acetylcholinesterase than other samples. Understanding the interplay between matrix composition, drying techniques, and powder properties provides insights for the development of plant-based products with tailored attributes, including potential health-linked properties.

Comparative assessment of phenolic composition profile and biological activities of green extract and conventional extracts of Salvia sclarea

In recent years, there have been an attempt to develop safe and environmental friendly solvents to replace conventional solvents, and use for extraction bioactive compounds from natural sources. A current investigation involved the preparation of green, methanolic, and ultrasonic extracts of S. sclarea, and compared their phenolic profiling using HPLC-DAD, antibacterial, antioxidant, and enzyme inhibition activities. The HPLC-DAD analysis revealed that Rosmarinic acid was the main content in all extracts, with Ellagic acid only present in the green extract. The green extract exhibited superior anti-biofilm activity against S. Aureus and E. Faecalis compared to the other extracts at MIC concentration. Furthermore, the green extract also displayed the highest inhibition of swarming motility in P. Aeruginosa with inhibition range 68.0 ± 2.1 (MIC) to 19.5 ± 0.6 (MIC/4). and better enzyme inhibitory activity against BChE (with IC50 = 131.6 ± 0.98 µg/mL) and AChE (with inhibition 47.00 ± 1.50%) compared to the other extracts; while, the ultrasonic extract showed strong inhibition of violacein production by C. Violaceum with a inhibition range 05.5 ± 0.1 (MIC/32) to 100 ± 0.00 (MIC), followed by the green extract with a inhibition range 15.0 ± 0.5 (MIC/8) to 100 ± 0.00 (MIC), additionally, the ultrasonic and methanoic extracts showed significant activity against urease enzyme with (IC50 = 171.6 ± 0.95 µg/mL and IC5 0 = 187.5 ± 1.32 µg/mL) respectively. Both the green and methanolic extracts showed considerable antioxidant activities, as β-carotene-linoleic acid (IC50 = 5.61 ± 0.47 µg/mL and 5.37 ± 0.27 µg/mL), DPPH· (IC50 = 19.20 ± 0.70 µg/mL and 16.31 ± 0.23 µg/mL), ABTS·+(IC50 = 8.64 ± 0.63 µg/mL and 6.50 ± 0.45 µg/mL) and CUPRAC (A0.5 = 17.22 ± 0.36 µg/mL and 12.28 ± 0.12 µg/mL) respectively, likewise the green extract performing better in metal chelating compared to the other extracts. The green extraction is reported as a cost effective and solvent free method for extracting natural products that produces compounds free of toxic chemicals. This could be the method to be used in the industries as a renewable method.

Malvidin and Its Mono- and Di-Glucosides Forms: A Study of Combining Both In Vitro and Molecular Docking Studies Focused on Cholinesterase, Butyrylcholinesterase, COX-1 and COX-2 Activities

Malvidin, one of the six most prominent anthocyanins found in various fruits and vegetables, may possess a wide range of health-promoting properties. The biological activity of malvidin and its glycosides is not entirely clear and has been relatively less frequently studied compared to other anthocyanins. Therefore, this study aimed to determine the relationship between the structural derivatives of malvidin and their anti-cholinergic and anti-inflammatory activity. The study selected malvidin (Mv) and its two sugar derivatives: malvidin 3-O-glucoside (Mv 3-glc) and malvidin 3,5-O-diglucoside (Mv 3,5-diglc). The anti-inflammatory activity was assessed by inhibiting the enzymes, specifically COX-1 and COX-2. Additionally, the inhibitory effects on cholinesterase activity, particularly acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), were evaluated. Molecular modeling was also employed to examine and visualize the interactions between enzymes and anthocyanins. The results revealed that the highest inhibitory capacity at concentration 100 µM was demonstrated by Mv 3-glc in relation to AChE (26.3 ± 3.1%) and BChE (22.1 ± 3.0%), highlighting the crucial role of the glycoside substituent at the C3 position of the C ring in determining the inhibitory efficiency of these enzymes. In addition, the glycosylation of malvidin significantly reduced the anti-inflammatory activity of these derivatives compared to the aglycone form. The IC50 parameter demonstrates the following relationship for the COX-1 enzyme: Mv (12.45 ± 0.70 µM) < Mv 3-glc (74.78 ± 0.06 µM) < Mv 3,5-diglc (90.36 ± 1.92 µM). Similarly, for the COX-2 enzyme, we have: Mv (2.76 ± 0.16 µM) < Mv 3-glc (39.92 ± 3.02 µM) < Mv 3.5-diglc (66.45 ± 1.93 µM). All tested forms of malvidin exhibited higher activity towards COX-2 compared to COX-1, indicating their selectivity as inhibitors of COX-2. Theoretical calculations were capable of qualitatively replicating most of the noted patterns in the experimental data, explaining the impact of deprotonation and glycosylation on inhibitory activity. It can be suggested that anthocyanins, such as malvidins, could be valuable in the development of treatments for inflammatory conditions and Alzheimer's disease and deserve further study.

Flavonols as a Potential Pharmacological Intervention for Alleviating Cognitive Decline in Diabetes: Evidence from Preclinical Studies

Diabetes mellitus is a complex metabolic disease associated with reduced synaptic plasticity, atrophy of the hippocampus, and cognitive decline. Cognitive impairment results from several pathological mechanisms, including increased levels of advanced glycation end products (AGEs) and their receptors, prolonged oxidative stress and impaired activity of endogenous mechanisms of antioxidant defense, neuroinflammation driven by the nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB), decreased expression of brain-derived neurotrophic factor (BDNF), and disturbance of signaling pathways involved in neuronal survival and cognitive functioning. There is increasing evidence that dietary interventions can reduce the risk of various diabetic complications. In this context, flavonols, a highly abundant class of flavonoids in the human diet, are appreciated as a potential pharmacological intervention against cognitive decline in diabetes. In preclinical studies, flavonols have shown neuroprotective, antioxidative, anti-inflammatory, and memory-enhancing properties based on their ability to regulate glucose levels, attenuate oxidative stress and inflammation, promote the expression of neurotrophic factors, and regulate signaling pathways. The present review gives an overview of the molecular mechanisms involved in diabetes-induced cognitive dysfunctions and the results of preclinical studies showing that flavonols have the ability to alleviate cognitive impairment. Although the results from animal studies are promising, clinical and epidemiological studies are still needed to advance our knowledge on the potential of flavonols to improve cognitive decline in diabetic patients.

Phytochemical screening, biological evaluation, anatomical, and morphological investigation of Ferula tingitana L. (Apiaceae)

Ferula tingitana L. is a high perennial plant and its leaf is an alternate arrangement and yellow, and its flowers are unisexual like other Apiaceae. It has been used as a spice and for various medicinal purposes in the Mediterranean region. The paper reports antidiabetic, antimicrobial, anticholinesterase, antioxidant, and genotoxic activities of leaves, flowers, stems, and fruits methanol extracts of F. tingitana. Also, quantitative determination of some secondary metabolites was also analyzed by LC-MS/MS. Moreover, chemical composition of essential oils was analyzed. Consequently, anatomical, and morphological properties of plant were investigated. Germacrene D (23.6%), 1,3,5-trimethylbenzene (18.4%), and α-pinene (50.0%) were found as the main compounds in flower, leaf, and stem oils, respectively. The cortex in stem, pedicel, and fruit is characterized by angular collenchyma cells and a distinct cambium layer. 6 compounds (quinic acid, fumaric acid, keracyanin chloride, cyanidin-3-O-glucoside, chlorogenic acid, hesperidin) were observed in samples. Leaf extract showed anticholinesterase activity. Leaf and flower extracts showed the highest % inhibition value on ABTS·+ and DPPH•. Leaf extract has the strongest antioxidant effect because it is rich in total phenolic contents. All extracts of F. tingitana were found generally effective against C. albicans. Stem extract was found effective against E. coli and flower extract was found more effective against S. enterica and C. albicans. Bacterial genotoxicity results showed that extracts did not have genotoxic activity on tester strains S. typhimurium and E. coli WP2uvrA. Thus, it revealed that extracts were genotoxic-ally safe at applied concentrations up to 3 mg/plate.

Effects of microwave and exogenous l-phenylalanine treatment on phenolic constituents, antioxidant capacity and enzyme inhibitory activity of Tartary buckwheat sprouts

The phenolic substances, antioxidant capacity, and enzyme inhibitory activity of germinated Fagopyrum tataricum (Tartary buckwheat) under different microwave and l-phenylalanine (l-Phe) were investigated for the potential of enriching polyphenols. With the germination of seeds, the contents of total phenolics and total flavonoids increased, the antioxidant capacity and enzyme inhibitory activity were enhanced. The highest contents of total phenolics and total flavonoids in Tartary buckwheat sprouts were 17.41 mg GAE/g and 6.26 g RE/100 g DW (7 days), respectively. Correlation analysis and principal component analysis indicated that T3 (microwave 250 W, 90 s; l-Phe 2.9 mmol/L) could effectively improve the content of polyphenols, enzyme inhibition activity and antioxidant capacity of Tartary buckwheat sprouts obviously. This study hopes to provide some new ideas for enriching phenolics and improving antioxidation of Tartary buckwheat sprouts.

Discovery of potent and selective dual cholinesterases and β-secretase inhibitors in pomegranate as a treatment for Alzheimer's disease

Pomegranate (Punica granatum L.) extract has been reported to inhibit cholinesterase and the β-site amyloid precursor protein cleaving enzyme 1 (BACE1); however, most of its constituents' potential inhibition of these enzymes remains unknown. Thus, we investigated the anti-Alzheimer's disease (anti-AD) potential of 16 ellagitannin and gallotannin, and nine anthocyanin derivatives' inhibition of BACE1, AChE, and BChE, and gallagic acid inhibited both the best. Further, a kinetic study identified different modes of inhibition, and a molecular docking simulation revealed that active compounds inhibited these three enzymes with low binding energy through hydrophilic and hydrophobic interactions in the active site cavities. Gallagic acid and castalagin decreased Aβ peptides secretion from neuroblastoma cells that overexpressed human β-amyloid precursor protein significantly by 10 μM. Further, treatment with gallagic acid and castalagin reduced BACE1 and APPsβ expression levels significantly without affecting amyloid precursor protein (APP) levels in the amyloidogenic pathway. Co-incubation of Aβ42 with gallagic acid reduced Aβ42-induced intracellular reactive oxygen species (ROS) production significantly. Our results suggest that pomegranate constituents, specifically gallagic acid, may be useful in developing therapeutic treatment modalities for AD.

Antihypertensive Activity in High Salt-Induced Hypertensive Rats and LC-MS/MS-Based Phytochemical Profiling of Melia azedarach L. (Meliaceae) Leaves

Melia azedarach L. leaves have been traditionally used but not scientifically evaluated for antihypertensive activity. The focus of the present work was to carry out the detailed phytochemical profiling and antihypertensive potential of methanolic extract and subsequent fractions of this plant. The tandem mass spectrometry-based phytochemical profiling of M. azedarach extract (Ma.Cr) and fractions was determined in negative ionization mode while molecular networking was executed using the Global Natural Product Social (GNPS) molecular networking platform. This study resulted in the identification of 29 compounds including flavonoid O-glycosides, simple flavonoids, triterpenoidal saponins, and cardenolides as the major constituents. Ma.Cr at the concentration of 300 mg/kg resulted in a fall in blood pressure (BP), i.e., 81.44 ± 2.1 mmHg in high salt-induced hypertensive rats in vivo, in comparison to normotensive group, i.e., 65.36 ± 1.8 mmHg at the same dose. A decrease in blood pressure was observed in anaesthetized normotensive and hypertensive rats treated with extract and various fractions of M. azedarach. A reasonable activity was observed for all fractions except the aqueous fraction. The highest efficacy was shown by the ethyl acetate fraction, i.e., 77.06 ± 3.77 mmHg in normotensive and 88.96 ± 1.3 mmHg in hypertensive anaesthetized rats. Ma.Cr and fractions showed comparatively better efficacy towards hypertensive rats as compared to rats with normal blood pressure. Blood pressure-lowering effects did not change upon prior incubation with atropine. In vitro testing of Ma.Cr and polarity-based fractions resulted in L-NAME sensitive, endothelium-dependent vasodilator effects on aortic tissues. Pretreatment of aorta preparations with Ma.Cr and its fractions also blocked K+-induced precontractions indicating Ca2+ channel blocking activity comparable to verapamil. The extract and polarity-based fractions did not reveal a vasoconstrictor response in spontaneously beating isolated rat aorta. Ma.Cr and fractions when used in atrial preparations resulted in negative inotropic and chronotropic effects. These effects in atrial preparations did not change in the presence of atropine. These effects of extract and fractions explained the antihypertensive potential of M. azedarach and thus provided a scientific basis for its ethnopharmacological use in the treatment of hypertension. Among the constituents observed, flavonoids and flavonoid O-glycosides were previously reported for antihypertensive potential.

Honeys as Possible Sources of Cholinesterase Inhibitors

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterised by low levels of the neurotransmitter (acetylcholine), oxidative stress, and inflammation of the central nervous system. The only currently available form of treatment entails the administration of AChE/BChE (acetylcholinesterase/butyrylcholinesterase) inhibitors to patients diagnosed with the disease. However, AD prevention is possible by administering the correct inhibitors with food. The aim of this study was to examine 19 types of honey in terms of their contents of cholinesterase inhibitors. The inhibition of AChE and BChE relative to the respective honey samples was evaluated using Ellman’s colorimetric method, including the “false-positive” effect. The highest potential for AChE inhibition was observed in the case of thyme honey (21.17% inhibition), while goldenrod honey showed the highest capacity for BChE inhibition (33.89%). Our study showed that honeys may provide a rich source of cholinesterase inhibitors and, in this way, play a significant role in AD.

Polyphenols composition and the biological effects of six selected small dark fruits

The health-promoting activities of fruits are in the limelight in view of the growing risks posed by civilisational diseases and are connected with polyphenols. The present study examined bilberry, blueberry, blackcurrant, redcurrant, cherry and plum for their polyphenolic content and biological activities. The contents of total polyphenolic compounds and their subclasses were determined. Liquid chromatography high-resolution mass spectrometry was used to characterise the polyphenolic profiles. Small dark fruits' antioxidant, anti-inflammatory, and anti-cholinesterase activities were also extensively determined. Significant qualitative and quantitative differences in the analysed fruits' polyphenols composition and biological activities were demonstrated. The highest polyphenolic contents and antioxidant activities were established in blackcurrant fruit, but bilberry also had our attention due to an additional mild influence on antioxidant enzymes. The condensed tannin content in small dark fruits is developed. All tested fruits exhibit anti-inflammatory and anti-cholinesterase activities.

Biological Activity of Extracts of Red and Yellow Fruits of Cornus mas L.-An In Vitro Evaluation of Antioxidant Activity, Inhibitory Activity against α-Glucosidase, Acetylcholinesterase, and Binding Capacity to Human Serum Albumin

Although extracts are broadly used in order to support the treatment of numerous diseases, only in a limited number of cases is the process of applying and establishing their mechanisms of action scientifically analyzed. Fruits of Cornelian cherry are an abundant source of iridoids, anthocyanins, flavonols and phenolic acids. The aim of the present study was to evaluate the in vitro bioactivity of red and yellow Cornelian cherry fruits’ extracts. The biological potential of extracts, in a broad sense, involved antioxidant activity in relation to phosphatidylcholine liposomes, inhibitory ability against α-glucosidase and acetylcholinesterase enzymes, as well as interactions with human serum albumin. Studies showed that both extracts were more effective in protecting liposome membranes against free radicals produced by AAPH in an aqueous environment due to the fact that they can be better eliminated by the hydrophilic components of the extracts than those produced by UVB radiation. Extracts exhibited inhibitory activity against acetylcholinesterase and α-glucosidase, wherein loganic acid extract showed noncompetitive inhibition of the enzyme. Moreover, extracts binded to albumin mainly through hydrogen bonds and van der Waals forces. Taken together, red and yellow cherry fruits’ extracts exhibit diverse biological properties and can be exploited as a source of natural therapeutic agents.

Neuroprotective effects of Lippia javanica (Burm.F.) Spreng. Herbal tea infusion on Lead-induced oxidative brain damage in Wistar rats

Background

Though Lippia javanica (Burm.f.) Spreng antioxidant activity has been demonstrated, its effect in protecting the brain from lead (Pb)-induced oxidative damage is unknown. This study investigated the effect of L. javanica against Pb-induced oxidative stress, inflammation, apoptosis and acetylcholinesterase activity in rat’s brain.

Methods

L. javanica herbal tea infusion was prepared, its phytochemical constituent was revealed by liquid chromatography-Mass spectrometer (LC-MS) and was administered simultaneously with Pb. Four groups of male Wistar rats (n = 5/group) were used: control received distilled water; Pb-acetate group received 50 mg Pb/ Kg bodyweight (bw), treatment group received 50 mg Pb/ Kg Pb-acetate + 5 ml/kg bw L. javanica and L. javanica group received 5 ml/Kg bw of L. javanica tea infusion only. After 6 weeks of treatment, oxidative status, acetylcholinesterase activity, inflammation and apoptosis was assessed in brain tissue which was also histologically examined.

Results

Mean brain and heart weight was reduced (p < 0.05) while liver and spleen weights were increased (p < 0.05) in Pb exposed animals but were prevented by L. juvanica treatment. Treatment with L. javanica increased (p < 0.05) overall brain antioxidant status (glutathione and superoxide dismutase activities) and reduced lipid peroxidation (p < 0.05) compared to the Pb exposed animals. Pro-inflammatory cytokine tumour necrotic factor-alpha, pro-apoptosis Bax protein and anticholinesterase activity were reduced (p < 0.05) in Pb-L. javanica treated animals compared to the Pb exposed group. Histological examination confirmed neuroprotective effects of L. javanica as evidenced by reduced apoptosis/necrosis and inflammation-induced vacuolization and oedema in the hippocampus. The L. javanica treatment alone had no detrimental effects to the rats. LC-MS analysis revealed L. javanica to be rich in phenolics.

Conclusions

This study demonstrated that L. javanica, rich in phenolics was effective in reducing Pb-induced brain oxidative stress, inflammation, apoptosis, acetylcholinesterase activity and neuronal damage.

Phenolic acids and flavonoids-rich Glechoma hederacea L. (Lamiaceae) water extract against H2 O2 -induced apoptosis in PC12 cells

Reactive oxygen species (ROS)-induced oxidative stress is reportedly associated with progressive neuronal cell damage. Glechoma hederacea L. (Lamiaceae), belonging to the Labiatae family, has demonstrated several biologic activities including depigmentation, antimelanogenic, antitumor, antioxidative, hepatoprotective, and anti-inflammatory activities. Previously, we reported that rosmarinic acid, chlorogenic acid, caffeic acid, rutin, genistin, and ferulic acids were the most abundant phytochemicals detected in hot water extracts of G. hederacea L. (HWG). This study aimed to study the neuroprotective effects of phenolic acids and flavonoid-rich HWG against hydrogen peroxide (H₂ O₂ )-induced oxidative damage in PC12 cells and its inhibitory effect on acetylcholinesterase (AChE). The experiment analyzed cytotoxicity, ROS production, mitochondrial transmembrane potential (MMP) level, and caspase-3 activity and used comet assay and antioxidant enzyme activity to determine the redox status of PC12 cells. Results showed that the inhibitory effect of HWG on AChE was in a competitive pattern (IC₅₀ , 23.23 mg/ml). HWG antagonized H₂ O₂ -mediated cytotoxicity and DNA damage, reduced ROS production, stabilized MMP, and inhibited caspase-3 activity and apoptosis. Furthermore, HWG inhibited the release of cytochrome C and apoptosis-inducing factors (AIF) and decreased the malondialdehyde levels in PC12 cells. Collectively, HWG rich in antioxidant phenolic acids and flavonoids may have neuroprotective effects. PRACTICAL APPLICATIONS: Polyphenolic compounds are one of the most important natural products, known to possess a range of health-promoting effects. In this study, it was found that HWG, which is rich in antioxidant phenolic acids and flavonoids, can protect PC12 cells from oxidative stress induced by H₂ O₂ and may have neuroprotective effects.

LC-ESI-QTOF-MS/MS Analysis, Cytotoxic, Antiviral, Antioxidant, and Enzyme Inhibitory Properties of Four Extracts of Geranium pyrenaicum Burm. f.: A Good Gift from the Natural Treasure

This study focused on the biological evaluation and chemical characterization of Geranium pyrenaicum Burm. f. Different solvent extracts (hexane, ethyl acetate, methanol, and water extracts) were prepared. The phytochemical profile, antioxidant, and enzyme inhibitory activity were investigated. Cytotoxicity was assessed using VERO, FaDu, HeLa and RKO cells. The antiviral activity was carried out against HSV-1 (Herpes simplex virus 1) propagated in VERO cell line. The aqueous extract, possessing high phenolic content (170.50 mg gallic acid equivalent/g extract), showed the highest reducing capacity (613.27 and 364.10 mg Trolox equivalent/g extract, for cupric reducing antioxidant capacity and ferric reducing antioxidant power, respectively), radical scavenging potential (469.82 mg Trolox equivalent/g extract, against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), metal chelating ability (52.39 mg ethylenediaminetetraacetic acid equivalent/g extract) and total antioxidant capacity (3.15 mmol Trolox equivalent/g extract). Liquid chromatography-electrospray ionization-quadrupole time-of-flight-mass spectrometry (LC-ESI-QTOF-MS/MS) alloved to tentatively identify a total of 56 compounds in the extracts, including ellagitannins, gallic acid and galloyl derivatives amongst others. The ethyl acetate extracts substantially depressed cholinesterase enzymes (4.49 and 12.26 mg galantamine equivalent/g extract against AChE and BChE, respectively) and α-amylase enzyme (1.04 mmol acarbose equivalent/g extract). On the other hand, the methanolic extract inhibited tyrosinase (121.42 mg kojic acid equivalent/g extract) and α-glucosidase (2.39 mmol acarbose equivalent/g extract) activities. The highest selectivity towards all cancer cell lines (SI 4.5-10.8) was observed with aqueous extract with the FaDu cells being the most sensitive (CC50 40.22 µg/mL). It can be concluded that the presence of certain bioactive antiviral molecules may be related to the high anti HSV-1 activity of the methanolic extract. This work has generated vital scientific data on this medicinal plant, which is a prospective candidate for the creation of innovative phyto-pharmaceuticals.

Anticholinesterase Activities of Different Solvent Extracts of Brewer's Spent Grain

Cholinesterases, involved in acetylcholine catabolism in the central and peripheral nervous system, have been strongly linked with neurodegenerative diseases. Current therapeutic approaches using synthetic drugs present several side effects. Hence, there is an increasing research interest in naturally-occurring dietary polyphenols, which are also considered efficacious. Food processing by-products such as brewer’s spent grain (BSG) would be a potential bio-source of polyphenols. In this study, polyphenol-rich BSG extracts using 60% acetone and 0.75% NaOH solutions were generated, which were further subjected to liquid–liquid partitioning using various organic solvents. The water-partitioned fractions of the saponified extracts had the highest total polyphenol content (6.2 ± 2.8 mgGAE/g dw) as determined by Folin–Ciocalteu reagent, while the LC-MS/MS showed ethyl acetate fraction with the highest phenolics (2.9 ± 0.3 mg/g BSG dw). The best inhibitions of acetyl- (37.9 ± 2.9%) and butyryl- (53.6 ± 7.7%) cholinesterases were shown by the diethyl ether fraction of the saponified extract. This fraction contained the highest sum of quantified phenolics (99 ± 21.2 µg/mg of extract), and with significant (p < 0.01) inhibitory contribution of decarboxylated-diferulic acid. Amongst the standards, caffeic acid presented the highest inhibition for both cholinesterases, 25.5 ± 0.2% for acetyl- and 52.3 ± 0.8% for butyryl-cholinesterase, respectively, whilst the blends insignificantly inhibited both cholinesterases. The results showed that polyphenol-rich BSG fractions have potentials as natural anti-cholinesterase agents.

Phytochemical analysis of Viburnum davidii Franch. and cholinesterase inhibitory activity of its dihydrochalcones

One flavonoid (quercetin, 1) and three dihydrochalcones (6''-O-p-hydroxybenzoyl-davidioside, 2, 4'-O-methyl-davidioside, 3, and davidioside, 4) were isolated from the leaves and young branches of Viburnum davidii Franch. All the structures were identified by comparison of their spectroscopic data (NMR and MS) with those present in literature. In addition, compounds 2-4 were evaluated for their cholinesterase inhibitory (ChEI) activity, for the first time. Accordingly, compounds 2 and 4 showed significant inhibition of both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC₅₀ values equal to 36.883 and 39.274 µM, respectively for the former and 39.504 and 43.101 µM, respectively for the latter.

Dual electrophoretically-mediated microanalysis in multiple injection mode for the simultaneous determination of acetylcholinesterase and α-glucosidase activity applied to selected polyphenols

Acetylcholinesterase (AChE) and α-glucosidase (α-glu) are key target enzymes in the search for novel strategies in the treatment of Alzheimer's disease and type II diabetes. Therefore, methods to assess the enzyme inhibition are of great value in the research field. Here is proposed a novel a dual electrophoretically-mediated microanalysis for the simultaneous determination of both enzymes' activity. In order to do so, the various solutions required for both assays were introduced in the capillary electrophoresis system using the multiple injections approach. Enzymatic kinetic parameters were tested, K_m for AChE and α-glu were 3.81 and 0.43 mmol L^-1. K_i values were 4.27 μmol L^-1 for neostigmine (an AChE inhibitor) and 0.40 mmol L^-1 for acarbose (an α-glu inhibitor). Results of IC₅₀ (concentration for 50% of inhibition) were 5.11 ± 0.47 μmol L^-1 and 0.58 ± 0,02 mmol L^-1 for neostigmine and acarbose, respectively. All parameters (except for K_i of neostigmine) were comparable with the literature, indicating a good reliability of the proposed method to evaluate these enzymes activity. Total time analysis was approximately 10 min, being possible to perform around 12 enzymatic assays per hour, with low sample and reagent consumption, thus satisfying some of the principles of green chemistry. The method was applied to evaluate 10 phenolic compounds, of wich p-coumaric acid showed the best inhibitory activity for AChE (40.14 ± 4.75% at 10 mg L^-1); and quercetin for α-glu (46.53 ± 4.90% at 10 mg L^-1).

Phenolic Profiles of Hardy Kiwifruits and Their Neuroprotective Effects on PC-12 and SH-SY5Y Cells against Oxidative Stress

Hardy kiwifruits (Actinidia arguta Planch.) have high amounts of antioxidants, including ascorbic acid (vitamin C) and phenolics. The anti-cholinesterase activity and neuroprotective effects of three different cultivars of hardy kiwifruits, cv. Mansu (A. arguta × A. deliciosa), cv. Haeyeon (A. arguta), and cv. Chiak (A. arguta), on PC-12 and SH-SY5Y cells were evaluated. Extraction of phenolics and vitamin C was carried out using 80% (v/v) aqueous ethanol and metaphosphoric acid assisted with homogenization, respectively. Hardy kiwifruit of cv. Mansu showed higher total phenolic, total flavonoid, and vitamin C contents and antioxidant capacity compared to the other tw°Cultivars of hardy kiwifruits, cv. Haeyeon and cv. Chiak. Analysis of high-performance liquid chromatography results revealed the presence of procyanidin B2, (?)-epicatechin, neochlorogenic acid, cryptochlorogenic acid, rutin, hyperoside, isoquercitrin, and astragalin in hardy kiwifruits. The three cultivars of hardy kiwifruits had a wide range of vitamin C content of 55.2?130.0 mg/100 g fresh weight. All three cultivars of hardy kiwifruits had protective effects on neuronal PC-12 and SHSY5Y cells exposed to hydrogen peroxide by increasing cell viability and reducing intracellular oxidative stress. Furthermore, the hardy kiwifruits inhibited acetylcholinesterase and butyrylcholinesterase. Collectively, these results suggest that hardy kiwifruits rich in antioxidants like phenolics and vitamin C have good potential as functional materials in neuroprotective applications.

Comparison of Phytochemicals, Antioxidant, and In Vitro Anti-Alzheimer Properties of Twenty-Seven Morus spp. Cultivated in Thailand

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder. To fight the disease, natural products, including mulberry, with antioxidant activities and inhibitory activities against key enzymes (acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and beta-secretase 1 (BACE-1)) are of interest. However, even in the same cultivars, mulberry trees grown in different populated locations might possess disparate amounts of phytochemical profiles, leading to dissimilar health properties, which cause problems when comparing different cultivars of mulberry. Therefore, this study aimed to comparatively investigate the phytochemicals, antioxidant activities, and inhibitory activities against AChE, BChE, and BACE-1, of twenty-seven Morus spp. cultivated in the same planting area in Thailand. The results suggested that Morus fruit samples were rich in phenolics, especially cyanidin, kuromanin, and keracyanin. Besides, the aqueous Morus fruit extracts exhibited antioxidant activities, both in single electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms, while strong inhibitory activities against AD key enzymes were observed. Interestingly, among the twenty-seven Morus spp., Morus sp. code SKSM 810191 with high phytochemicals, antioxidant activities and in vitro anti-AD properties is a promising cultivar for further developed as a potential mulberry resource with health benefits against AD.

Mulberry Fruit Cultivar 'Chiang Mai' Prevents Beta-Amyloid Toxicity in PC12 Neuronal Cells and in a Drosophila Model of Alzheimer's Disease

Alzheimer's disease (AD) is the most common form of dementia, characterized by chronic neuron loss and cognitive problems. Aggregated amyloid beta (Aβ) peptides, a product of cleaved amyloid precursor protein (APP) by beta-secretase 1 (BACE-1), have been indicated for the progressive pathogenesis of AD. Currently, screening for anti-AD compounds in foodstuffs is increasing, with promising results. Hence, the purpose of this study was to investigate the extraction conditions, phytochemical contents, and anti-AD properties, targeting Aβ peptides of Morus cf. nigra 'Chiang Mai' (MNCM) both in vitro and in vivo. Data showed that the aqueous extract of MNCM contained high amounts of cyanidin, keracyanin, and kuromanin as anthocyanidin and anthocyanins. The extract also strongly inhibited cholinesterases and BACE-1 in vitro. Moreover, MNCM extract prevented Aβ-induced neurotoxicity and promoted neurite outgrowth in neuronal cells. Interestingly, MNCM extract reduced Aβ1-42 peptides and improved locomotory coordination of Drosophila co-expressing human APP and BACE-1, specifically in the brain. These findings suggest that MNCM may be useful as an AD preventive agent by targeting Aβ formation.

Activity-guided isolation of cholinesterase inhibitors quercetin, rutin and kaempferol from Prunus persica fruit

Prunus persica fruit is a source of anti-cholinesterase agents and led to an increase of acetylcholine levels in brain tissue as a usefull tool in the Alzheimer's disease therapy. This study aimed to propose a convenient method for the purification of cholinesterase inhibitors from P. persica water extract. Water extract from the fruit was ultrafiltered (0.2 μm→5 kDa→3 kDa) followed by preparative chromatography (Sephadex LH-20, high pressure C18) and high pressure analytical C18 chromatography. The chemical structures of inhibitors were confirmed using infrared and ¹H-NMR spectroscopies. The anti-acetylcholinesterase activity was measured using the colorimetric method in fractions obtained after each stage of purification. Polyphenolic cholinesterase inhibitors identified in peach fruit were kaempferol, quercetin and quercetin-3-O-rhamnoglucoside (rutin). The relatively fast purification procedure elaborated in this work can be adopted for the isolation of phenolic cholinesterase inhibitors from fruit extracts related to P. persica fruit.

Dihydrochalcones: Methods of Acquisition and Pharmacological Properties-A First Systematic Review

Dihydrochalcones are a class of secondary metabolites, for which demand in biological and pharmacological applications is still growing. They posses several health-endorsing properties and, therefore, are promising candidates for further research and development. However, low content of dihydrochalcones in plants along with their low solubility and bioavailability restrict the development of these compounds as clinical therapeutics. Therefore, chemomicrobial and enzymatic modifications are required to expand their application. This review aims at analyzing and summarizing the methods of obtaining dihydrochalcones and of presenting their pharmacological actions that have been described in the literature to support potential future development of this group of compounds as novel therapeutic drugs. We have also performed an evaluation of the available literature on beneficial effects of dihydrochalcones with potent antioxidant activity and multifactorial pharmacological effects, including antidiabetic, antitumor, lipometabolism regulating, antioxidant, anti-inflammatory, antibacterial, antiviral, and immunomodulatory ones. In addition, we provide useful information on their properties, sources, and usefulness in medicinal chemistry.

Chemometric discrimination of three Pistacia species via their metabolic profiling and their possible in vitro effects on memory functions

Alzheimer's disease (AD) is the most widespread neurodegenerative disease; there are around ten million new cases of Alzheimer yearly worldwide especially in middle or low-income countries. Pistacia is a genus of flowering plants including the well-known, economically important P. chinensis Bunge, P. lentiscus L. and P. khinjuk. In this study, the metabolic profiling of Pistacia leaves extracts was achieved via UHPLC-ESI-MS analysis and GC-MS analysis employing chemometric analysis for their discrimination. In addition, the methanolic extracts of different Pistacia species were assessed for their anti-cholinesterase and anti-inflammatory activities by various in vitro assays. 37 and 30 metabolites belonging to different classes were identified by UHPLC-ESI-MS and GC-MS analyses respectively. Chemometric analysis revealed that P. lentiscus and P. khinjuk were more closely related chemically to each other. All studied Pistacia leaves extracts showed apparent anti-cholinesterase and anti-inflammatory activities, which promotes their use in the prevention and management of AD.

Comparative biophysical characterization: A screening tool for acetylcholinesterase inhibitors

Among neurodegenerative diseases, Alzheimer’s disease (AD) is one of the most grievous disease. The oldest cholinergic hypothesis is used to elevate the level of cognitive impairment and acetylcholinesterase (AChE) comprises the major targeted enzyme in AD. Thus, acetylcholinesterase inhibitors (AChEI) constitutes the essential remedy for the treatment of AD. The study aims to evaluate the interactions between natural molecules and AChE by Surface Plasmon Resonance (SPR). The molecules like alkaloids, polyphenols and substrates of AChE have been considered for the study with a major emphasis on affinity and kinetics. To better understand the activity of small molecules, the investigation is supported by both experimental and theoretical approach such as fluorescence, Circular Dichroism (CD) and molecular docking studies. Amongst the screened ones tannic acid showed promising results compared with others. The methodology followed here have highlighted many molecules with a higher affinity towards AChE and these findings may take lead molecules generated in preclinical studies to treat neurodegenerative diseases. Additionally, we suggest a unique signature for the heterogeneous analyte model using competitive experiments for analyzing simultanous interactions of both the analytes.

Protective Influence of Phyllanthus Muellarianus on Ciprofloxacin-Induced Neurotoxicity in Male Rats

Phyllanthus muellarianus (Kuntze) Exell. (Euphorbiacea) leaves are widely used in the treatment of neurological disorders in Nigeria. We investigated the protective effect of aqueous leaf extract of Phyllanthus muellarianus on ciprofloxacin neurotoxicity in male rats. Control rats (Group A) received distilled water, Groups C-E According to the Animal grouping and treatment section, Group B did not receive P. muellarianus> rats were administered 100, 200, and 400 mg/kg body weight P. muellarianus, respectively, and Group F rats received 200 mg/kg body weight valproate orally for 7 days. In addition, groups B-F rats were orally administered ciprofloxacin for 7 days. Motor coordination and motor function were assessed using narrow beam and landing foot splay distance. The levels of neurotransmitter and oxidative stress biomarkers were also determined. Aqueous leaf extract of P. muellarianus significantly attenuated ciprofloxacin-mediated increases in narrow beam, landing foot splay distance, and gait scores. Ciprofloxacin-mediated depletion of acetylcholine and dopamine in the brains of rats was significantly annulled by P. muellarianus. Furthermore, the extract significantly reversed ciprofloxacin-mediated increases in acetylcholinesterase, monoamine oxidase A, and monoamine oxidase B by 73.13%, 71.52%, and 86.54%, respectively. The altered biomarkers of oxidative stress were significantly reversed by P. muellarianus. Overall, the results of this study show that P. muellarianus reversed ciprofloxacin-induced neurotoxicity by restoring ciprofloxacin-mediated alterations in acetylcholine, dopamine, acetylcholinesterase, monoaminergic enzymes, and oxidative stress biomarkers in the brains of rats.

Phytochemical composition and the cholinesterase and xanthine oxidase inhibitory properties of seed extracts from the Washingtonia filifera palm fruit

The chemical composition and biological properties of palm Washingtonia filifera (Lindl.) H. Wendl. seeds are seldom studied.

Anticholinergic effects of Actinidia arguta fruits and their polyphenol content determined by liquid chromatography-photodiode array detector-quadrupole/time of flight-mass spectrometry (LC-MS-PDA-Q/TOF)

This study discusses polyphenolic compounds identified and quantified in Actinidia arguta fruits by LC-MS-PDA-Q/TOF method and in vitro anticholinergic activity. Notably, of 31 compounds, including 16 flavonols, 7 flavanols, 7 phenolic acids, and 1 anthocyanin were identified or tentatively identified on the basis of their retention times, accurate mass measurements and subsequent mass fragmentation data, or by comparison with reference substances and literature. Among the detected compounds, 27 were reported for the first time in A. arguta fruits. The content of total polyphenols equal 845.54 mg/100 g dry weight (dw), and flavanols predominat (92% of total phenolic compounds). Flavonol derivatives, mainly glycosylated and acetylated forms of quercetin (22.64 mg/100 g dw) and kaempferol (18.40 mg/100 g dw) were quantified. The total content of phenolic acids was 29.63 mg/100 g dw, and neochlorogenic acid predominant. This anticholinergic activity effect of A. arguta fruits can be explained by the Pearson's correlation found between flavonols (r = 0.709 and 0.678), phenolic acids (r = 0.513 and 0.487), flavan-3-ols (r = 0.466 and 0.443) and anthocyanins (r = 0.312 and 0.301) for acetylcholinesterase (AChE) or butylcholinoesterase (BuChE), respectively. The data compiled from the quantitative polyphenol indicate that A. arguta fruits could be regarded as a promising source of bioactive functional food.

In vitro multimodal-effect of Trichilia catigua A. Juss. (Meliaceae) bark aqueous extract in CNS targets

ETHNOPHARMACOLOGICAL RELEVANCE

The bark of Trichilia catigua A. Juss. (Meliaceae), popularly known as "big catuaba", is traditionally used in Brazilian folk medicine for its neuroactive potential as memory stimulant, and antinociceptive and antidepressant effects.

AIM OF THE STUDY

To study the aqueous extract of T. catigua bark as dual inhibitor of monoamine oxidase A (MAO-A) and acetylcholinesterase (AChE). To explore its antioxidant potential through interaction with xanthine/xanthine oxidase (X/XO) pathway, and to attempt a relationship between its phenolic profile and effects displayed.

MATERIALS AND METHODS

Phenolic profiling was achieved by HPLC-DAD-ESI/MSⁿ and UPLC-ESI-QTOF-MS analyses. The capacity to inhibit hMAO-A was assessed in vitro, as was that for AChE, evaluated in rat brain homogenates. The direct inhibition of the X/XO pathway and the scavenging of superoxide anion radical were the selected in vitro models to explore the antioxidant potential. The cytotoxic effects were assayed in the human neuronal SH-SY5Y cells by MTT reduction, after direct exposure (24h).

RESULTS

Twenty-six compounds were identified and quantified (551.02 ± 37.61mg/g of lyophilized extract). The phenylpropanoid substituted flavan-3-ols were the most representative compounds (~81% of quantified mass). The extract inhibited hMAO activity in a concentration-dependent manner (IC₅₀ = 121.06 ± 2.13μg/mL). A mixed model of inhibition of AChE activity was observed, reflected by the pronounced increase of Km values and a more discreet effect over the Vmax parameters, calculated from Michaelis-Menten fitted equations. In addition, it was demonstrated that the extract directly inhibits the X/XO pathway (IC₅₀ = 121.06 ± 2.13μg/mL) and also imbalances the oxidative stress acting as superoxide anion radical scavenger (EC₅₀ = 104.42 ± 10.67μg/mL), an oxidative by-product of this reaction. All these neuroprotective and neurotrophic effects were displayed within the non-toxic range of concentrations (0.063-0.500μg/mL) in SH-SY5Y cells.

CONCLUSIONS

Our results validate the traditional use of T. catigua bark for its neuroactive and neuroprotective potential. A novel approach upon its application towards the management of neurodegenerative and related symptomatology was likewise demonstrated.

Phytochemical analysis, molecular docking and antiamnesic effects of methanolic extract of Silybum marianum (L.) Gaertn seeds in scopolamine induced memory impairment in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Silybum marianum (L.) Gaertn and its main component silymarin have been extensively studied and have been found effective in various neurological disorders.

AIMS OF THE STUDY

The aim of the current study is to identify phytoconstituents in the methanolic extract (Me. Ext) of Silybum marianum (L.) Gaertn seeds and to study in-vivo the anti-amnesic effects along with in vitro antioxidant and acetylcholinesterase (AChE) and buteryl cholinesterase (BChE) inhibition potential. Induced fir docking (IFD) results have confirmed that quercetin, morin and rutin showed good affinity when docked into AChE binding site.

MATERIALS AND METHODS

The present study investigates the in-vitro AChE and BChE inhibition potential of the Me-Ext of Silybum marianum (L.) Gaertn at various concentrations (31.25, 62.50, 125, 250, 500, 1000µg/mL) using Ellman's spectrophotometric analysis, while antioxidant potential against DPPH and ABTS were determined using Brand-Williams spectrophotometric method. Furthermore, the in-vivo anti-amnesic effects of Me. Ext at the dose level of 50, 100 and 200mg/kg were also evaluated using scopolamine -induced memory impairment in mice in the novel object recognition test (NORT) and Y-maze test.

RESULTS

The Me. Ext showed a concentration dependent inhibition of AChE and BChE with IC50 values of 110 and 130µg/mL respectively and antioxidant activity against DPPH and ABTS with IC50 values 280 and 220µg/mL, respectively. In mice, Me. Ext reversed the amnesia induced by scopolamine as indicated by a dose-dependent increase in spontaneous alternation performance in the Y-maze task (p< 0.05 versus scopolamine) and increase in the discrimination index in the NORT comparable to the standard drug donepezil 2mg/kg. HPLC-UV analysis showed the presence of quercetin, rutin and morin. Induced fit docking (IFD) was performed using quercetin, rutin and morin, Glide Gscore and IFD score of all compounds were consistent with their experimental AChE inhibitory activities.

CONCLUSION

The results indicate that Silybum marianum (L.) Gaertn could be a new source for the isolation of phytoconstituents useful in cognition and memory disorders such as Alzheimer's disease.

Phytochemical profiles, antioxidant and anti-acetylcholinesterasic activities of the leaf extracts of Rhamnus lycioides subsp. oleoides (L.) Jahand. & Maire in different solvents

In this work, the extracts obtained with different solvents from the leaves of Rhamnus lycioides subsp. oleoides (L.) Jahand. & Maire were studied for their phytochemical profile and then for their antioxidant and acetylcholinesterase inhibitory activities. The phytochemical profiles of the extracts in n-hexane, dichloromethane, ethyl acetate, methanol, anthraquinone rich and water, showed the presence of different compounds belonging to several classes of natural products such as flavonoids, anthraquinones, saccharides and fatty acids. For what concerns the biological tests, the ethyl acetate, methanol and anthraquinone rich extracts showed the highest activities in both assays due to the high amount of compounds possessing those properties such as flavonoids and anthraquinones. By consequence, these specific extracts of the species may be considered to be potential sources of natural antioxidant and anti-acetylcholinesterasic compounds.

Molecular docking and antiamnesic effects of nepitrin isolated from Rosmarinus officinalis on scopolamine-induced memory impairment in mice

Rosmarinus officinalis has long been known as the herb of remembrance. The present study was undertaken to investigate the anti-amnesic effects of nepitrin isolated from Rosmarinus officinalis using in-vivo models of Y-maze and novel object recognition test (NORT) along with in vitro antioxidant and acetylcholinesterase (AChE) and buterylcholinesterase (BuChE) inhibition potential. Nepitrin showed a concentration dependent inhibition of AChE and BuChE enzymes with IC₅₀ values of 65 and 72μg/mL, respectively and antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) with IC₅₀ values 270 and 210μg/mL, respectively. In mice, nepitrin reversed the amnesia induced by scopolamine as indicated by a dose-dependent increase in spontaneous alternation performance in the Y-maze task (p <0.05 versus scopolamine) and increase in the discrimination index in the novel object recognition test (NORT) comparable to the standard drug donepezil 2mg/kg. Molecular docking studies were performed and the GlideScore of nepitrin was consistent with its experimental AChE inhibitory activities. Nepitrin occupied the same binding site forming similar interactions to those formed by donepezil in the crystal structure. Thus, nepitrin could provide a lead for the development of therapeutic agent useful in cognition and memory disorders such as Alzheimer's disease.

Neuroprotective Effects of Pomegranate Peel Extract after Chronic Infusion with Amyloid-β Peptide in Mice

Alzheimer’s disease is a chronic and degenerative condition that had no treatment until recently. The current therapeutic strategies reduce progression of the disease but are expensive and commonly cause side effects that are uncomfortable for treated patients. Functional foods to prevent and/or treat many conditions, including neurodegenerative diseases, represent a promising field of study currently gaining attention. To this end, here we demonstrate the effects of pomegranate (Punica granatum) peel extract (PPE) regarding spatial memory, biomarkers of neuroplasticity, oxidative stress and inflammation in a mouse model of neurodegeneration. Male C57Bl/6 mice were chronically infused for 35 days with amyloid-β peptide 1–42 (Aβ) or vehicle (control) using mini-osmotic pumps. Another group, also infused with Aβ, was treated with PPE (p.o.– βA+PPE, 800 mg/kg/day). Spatial memory was evaluated in the Barnes maze. Animals treated with PPE and in the control group exhibited a reduction in failure to find the escape box, a finding that was not observed in the Aβ group. The consumption of PPE reduced amyloid plaque density, increased the expression of neurotrophin BDNF and reduced the activity of acetylcholinesterase enzyme. A reduction in lipid peroxidation and in the concentration of the pro-inflammatory cytokine TNF-α was also observed in the PPE group. No hepatic lesions were observed in animals treated with PPE. In conclusion, administration of pomegranate peel extract has neuroprotective effects involving multiple mechanisms to prevent establishment and progression of the neurodegenerative process induced by infusion with amyloid-β peptide in mice.

In Vitro Antioxidant, Anti-Diabetes, Anti-Dementia, and Inflammation Inhibitory Effect of Trametes pubescens Fruiting Body Extracts

Trametes pubescens, white rot fungus, has been used for folk medicine in Asian countries to treat ailments such as cancer and gastrointestinal diseases. This study was initiated to evaluate the in vitro antioxidant, anti-diabetes, anti-dementia, and anti-inflammatory activities of T. pubescens fruiting bodies. The 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging activities of T. pubescens methanol (ME) and hot water (HWE) extracts (2.0 mg/mL) were comparable to butylated hydroxytoluene (BHT), the positive control. However, the chelating effects of ME and HWE were significantly higher than that of BHT. The HWE (6 mg/mL) also showed comparable reducing power to BHT. Eleven phenol compounds were detected by high performance liquid chromatography (HPLC) analysis. The α-amylase and α-glucosidase inhibitory activities of the ME and HWE of the mushroom were lower than Acarbose, the standard reference; however, the inhibitory effects of the mushroom extracts at 2.0 mg/mL were moderate. The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory effects of ME and HWE were moderate and comparable with galanthamine, the standard drug to treat early stages of Alzheimer's disease (AD). The ME had a neuroprotective effect against glutamate-induced PC-12 cell cytotoxicity at the concentration range of 2-40 μg/mL. The mushroom extracts also showed inflammation inhibitory activities such as production of nitric oxide (NO) and expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-induced murine macrophage-like cell lines (RAW 264.7) and significantly suppressed the carrageenan-induced rat paw-edema. Therefore, fruiting body extracts of T. pubescens demonstrated antioxidant related anti-diabetes, anti-dementia and anti-inflammatory activities.

Acetylcholinesterase and carbonic anhydrase isoenzymes I and II inhibition profiles of taxifolin

Taxifolin, also known as dihydroquercetin, is a flavonoid commonly found in plants. Carbonic anhydrase (CA, EC 4.2.1.1) plays an important role in many critical physiological events including carbon dioxide (CO2)/bicarbonate (HCO3(-)) respiration and pH regulation. There are 16 known CA isoforms in humans, of which human hCA isoenzymes I and II (hCA I and II) are ubiquitous cytosolic isoforms. In this study, the inhibition properties of taxifolin against the slow cytosolic isoenzyme hCA I, and the ubiquitous and dominant rapid cytosolic isoenzyme hCA II were studied. Taxifolin, as a naturally bioactive flavonoid, has a K(i) of 29.2 nM against hCA I, and 24.2 nM against hCA II. For acetylcholinesterase enzyme (AChE) inhibition, K(i) parameter of taxifolin was determined to be 16.7 nM. These results clearly show that taxifolin inhibited both CA isoenzymes and AChE at the nM levels.

Phytochemical analysis, antioxidant, antistress, and nootropic activities of aqueous and methanolic seed extracts of ladies finger (Abelmoschus esculentus L.) in mice

Abelmoschus esculentus L. (ladies finger, okra) is a well-known tropical vegetable, widely planted from Africa to Asia and from South Europe to America. In the present study, we investigated the in vitro antioxidant capacity and in vivo protective effect of the aqueous and methanolic seed extracts of Abelmoschus esculentus against scopolamine-induced cognitive impairment using passive avoidance task and acute restraining stress-induced behavioural and biochemical changes using elevated plus maze (EPM) and forced swimming test (FST) in mice. Our results demonstrated that the pretreatment of mice with aqueous and methanolic seed extracts of Abelmoschus esculentus (200 mg/kg, p.o.) for seven days significantly (P < 0.01) attenuated scopolamine-induced cognitive impairment in the passive avoidance test. In addition, these extracts significantly reduced the blood glucose, corticosterone, cholesterol, and triglyceride levels elevated by acute restraint stress and also significantly increased the time spent in open arm in EPM and decreased the immobility time in FST. It has also been revealed that these extracts showed a significant antioxidant activity and no signs of toxicity or death up to a dose of 2000 mg/kg, p.o. These results suggest that the seed extracts of Abelmoschus esculentus L. possess antioxidant, antistress, and nootropic activities which promisingly support the medicinal values of ladies finger as a vegetable.

Antioxidant activity and acetylcholinesterase inhibition of grape skin anthocyanin (GSA)

We aimed to investigate the antioxidant and acetylcholinesterase inhibitory activities of the anthocyanin rich extract of grape skin. Grape skin anthocyanin (GSA) neutralized free radicals in different test systems, such as 2,-2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, to form complexes with Fe²⁺ preventing 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis and oxidative DNA damage. Moreover, GSA decreased reactive oxygen species (ROS) generation in isolated mitochondria thus inhibiting 2',-7'-dichlorofluorescin (DCFH) oxidation. In an in vivo study, female BALB/c mice were administered GSA, at 12.5, 25, and 50 mg per kg per day orally for 30 consecutive days. Herein, we demonstrate that GSA administration significantly elevated the level of antioxidant enzymes in mice sera, livers, and brains. Furthermore, GSA inhibited acetylcholinesterase (AChE) in the in vitro assay with an IC₅₀ value of 363.61 µg/mL. Therefore, GSA could be an excellent source of antioxidants and its inhibition of cholinesterase is of interest with regard to neurodegenerative disorders such as Alzheimer’s disease.