Search Results (1,949)

Eriobotrya japonica (Thunb.) Lindl. leaves are rich in polyphenolic compounds, yet their toxicological effects in aquatic models remain poorly understood. This study evaluated the impact of a hydroethanolic E. japonica leaf extract on zebrafish embryos through the use of morphological, behavioral, and biochemical parameters. The 96 h LC₅₀ was determined as 189.8 ± 4.5 mg/L, classifying the extract as practically non-toxic, according to OECD guidelines. Thereby, embryos were exposed for 90 h to 75 and 150 mg/L concentrations of the E. japonica leaf extract. While no significant effects were noted at the lowest concentration of 150 mg/L, significant developmental effects were observed, including reduced survival, delayed hatching, underdevelopment of the swim bladder, and retention of the yolk sac. These malformations were accompanied by marked behavioral impairments. Biochemical analysis revealed a concentration-dependent increase in superoxide dismutase (SOD) and catalase (CAT) activity, suggesting the activation of antioxidant defenses, despite no significant change in reactive oxygen species (ROS) levels. This indicates a potential compensatory redox response to a pro-oxidant signal. Additionally, the acetylcholinesterase (AChE) activity was significantly reduced at the highest concentration, which may have contributed to the observed neurobehavioral changes. While AChE inhibition is commonly associated with neurotoxicity, it is also a known therapeutic target in neurodegenerative diseases, suggesting concentration-dependent dual effects. In summary, the E. japonica leaf extract induced concentration-dependent developmental and behavioral effects in zebrafish embryos, while activating antioxidant responses without triggering oxidative damage. These findings highlight the extract’s potential bioactivity and underscore the need for further studies to explore its safety and therapeutic relevance. Full article

Heavy metals are a major toxicological concern due to their adverse effects on human health, particularly in children exposed to contaminated areas. This study evaluated biomarkers of exposure in 253 children aged 6 to 12 from Magangue, Achi, and Arjona (Bolivar, Colombia), analyzing their relationship with neurotoxicity and hematological markers. The mean Pb concentrations at the study sites were 1.98 µg/g (Magangue) > 1.51 µg/g (Achi) > 1.24 µg/g (Arjona). A similar pattern was observed for Cd concentrations for Magangue (0.39 µg/g) > Achi (0.36 µg/g) > Arjona (0.14 µg/g). In contrast, Se concentrations followed a different trend for Arjona (0.29 µg/g) > Magangue (0.21 µg/g) > Achi (0.16 µg/g). The proportion of Se/Pb molar ratios > 1 was higher in Arjona (3.8%) than in Magangue (0.9%) and Achi (2.0%). For Se/Cd ratios, values > 1 were also more frequent in Arjona (70.7%), exceeding 20% in the other two locations. Significant differences were found among locations in red and white blood cell parameters and platelet indices. Neurotransmitter-related biomarkers, including serotonin, monoamine oxidase A (MAO-A), and acetylcholinesterase levels, also varied by location. Principal component analysis showed that Pb and Cd had high loadings on the same component as PLT, WBC, and RDW, and while Se loaded together with HGB, PDW, MCHC, MCH, and MCV, suggesting distinct hematological patterns associated with each element. Multiple linear regression analysis demonstrated a statistically significant inverse association between hair Pb levels and serotonin concentrations. Although MAO-A and Cd showed negative β coefficients, these associations were not statistically significant after adjustment. These findings highlight the potential impact of toxic element exposure on key hematological and neurochemical parameters in children, suggesting early biological alterations that may compromise health and neurodevelopment. Full article

Iridoids are compounds recognized for their neuroprotective properties and their potential application in the treatment of neurodegenerative diseases. Geniposide (GP) and asperuloside (ASP) are iridoids that have demonstrated some biological activities. In this study, the potential neuroprotective effects of these iridoids were evaluated through in silico and in vivo assays, using Caenorhabditis elegans (C. elegans) strains CF1553 (sod-3::GFP), GA800 (cat::GFP), and CL2166 (gst-4::GFP). The results suggested that neither compound appears to have good passive permeability through the blood–brain barrier (BBB). However, an active transport mechanism involving the glucose transporter GLUT-1 may be present, as both compounds contain glucose in their molecular structure. In addition, they can inhibit the activity of both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). GP at 1 and 2 mM reversed the H₂O₂-induced increase in sod-3 expression, while ASP at 1 and 2 mM reversed the increase in gst-4 expression. Worm survival was more adversely affected by higher concentrations of GP than ASP, although both similarly reduced acetylcholinesterase activity. These findings suggest that GP and ASP exhibit very low toxicity both in silico and in vivo in C. elegans, and positively modulate key enzymes involved in antioxidant pathways, highlighting their potential for neuroprotective applications. Full article

Exposure to xenobiotics causes pathophysiological changes in fish, including oxidative stress and neurotoxicity. Here, we describe the biochemical mechanisms underlying oxidative stress (i.e., redox imbalance) and the biochemical markers commonly used to assess its level. Neurotoxicity biomarkers used in fish include behavioral, histological, molecular, neurotransmitter-related, and enzymatic parameters, among which acetylcholinesterase (AChE) activity is the most commonly measured. We therefore also review the changes in AChE activity in fish exposed to common xenobiotics. In most cases, AChE activity decreased in a concentration- and time-dependent manner, although some studies reported no change or even an increase. We emphasize the relevance of all the parameters discussed in the context of fish toxicology studies. Full article

Cetraria islandica (L.) Ach. (CI) is a lichen from the Parmeliaceaea family used in medicine. However, the low solubility of CI secondary metabolites in water limits the application of lichen extract and compounds. It prompted us to study the systems of cyclodextrins (CDs) (β-CD, γ-CD, HP-β-CD, and HP-γ-CD) with the CI acetone or CI methanol extracts prepared using grinding and solvent evaporation methods. The content of fumarprotocetraric acid (FPCA), a key CI metabolite, was quantified using HPLC. CD–extract systems were characterized by X-ray powder diffraction (XRPD) and Fourier-transform infrared (FTIR) spectroscopy. Biological activity was evaluated using cell-free assays: a Folin–Ciocalteu analysis, DPPH test, acetylcholinesterase, butyrylcholinesterase, and tyrosinase inhibitions. Dissolution profiles were also assessed. The best biological and physicochemical results were obtained for systems prepared with HP-β-CD and HP-γ-CD via solvent evaporation, showing higher activity and enhanced FPCA release compared to the pure extracts. To the best of our knowledge, this is the first study to report the preparation and characterization of CD-based systems with CI extracts. The obtained results encourage us to continue our research on CI to improve the physicochemical properties of its active compounds. Full article

The genera Allium (Liliaceae) and Anchusa (Boraginaceae) are flowering plant genera with a rich diversity, also including the Allium kharputense Freyn & Sint. and Anchusa azurea Mill. var. azurea species. The antioxidant, anti-Alzheimer’s disease (AD), antidiabetic, and antiglaucoma effects of the Allium kharputense Freyn & Sint. and Anchusa azurea Mill. var. azurea species, which are commonly eaten foods in the Southeast of Türkiye in the treatment of several diseases, were studied. To interpret the antioxidant capacities of ethanol extract of two plant species, aerial parts were analyzed by ABTS and DPPH assays. The IC₅₀ values of A. kharputense and A. azurea ethanol and water extracts for ABTS^•+ activities were recorded in the range of 30.93 to 33.94 µg/mL and 33.45 to 33.78 µg/mL, respectively. Also, DPPH^• activities were measured at 30.78 to 36.87 µg/mL and 31.67 to 32.45 µg/mL, respectively. The best of the IC₅₀ values was measured in the ethanol extract of A. kharputense as 30.78 µg/mL for DPPH scavenging activity. The total phenolic and flavonoid quantities in A. kharputense and A. azurea plants were measured. The highest phenolic and flavonoid contents of A. kharputense and A. azurea species were recorded in amounts of 445.52 and 327.35 mg GAE/g in ethanol extracts, respectively, and 332.88 and 234.03 mg QE/g in ethanol extracts, respectively. The effects of A. kharputense and A. azurea on diabetes, AD, and glaucoma were studied on the target enzymes of diseases. The most efficient IC₅₀ values were recorded at 10.72 μg/mL against α-glycosidase, 35.01 μg/mL against AChE, 38.05 μg/mL against BChE, 9.21 μg/mL towards hCA I, and 81.02 μg/mL towards hCA II isoenzymes. The kinds and amounts of phenolic compounds in A. kharputense and A. azurea were determined using LC-MS/MS against 53 standards. A. kharputense and A. azurea plants have prospective use in enhancing glaucoma, diabetes, AD, Parkinson’s disease, epilepsy, and cancerous disorders. Full article

A series of rivastigmine hybrids, incorporating rivastigmine fragments (RIV) and a set of different antioxidant scaffolds, were designed, synthesized, and evaluated as multifunctional agents for the potential therapy of Alzheimer’s disease (AD). In vitro bioactivity assays indicated that some compounds have very good antioxidant (radical-scavenging) activity. The compounds also displayed good inhibitory activity against cholinesterases, though the bigger-sized hybrids showed higher inhibitory ability for butyrylcholinesterase (BChE) than for acetylcholinesterase (AChE), due to the larger active site cavity of BChE. All the hybrids exhibited an inhibition capacity for self-induced amyloid-β (Aβ_1–42) aggregation. Furthermore, cell assays demonstrated that some compounds showed capacity for rescuing neuroblastoma cells from toxicity induced by reactive oxygen species (ROS). Among these RIV hybrids, the best in vitro multifunctional capacity was found for the caffeic acid derivatives enclosing catechol moieties (4AY5, 4AY6), though the Trolox derivatives (4AY2, 4BY2) presented the best cell neuroprotective activity against oxidative damage. Molecular-docking studies provided structural insights into the binding modes of RIV-based hybrids to the cholinesterases, revealing key interaction patterns despite some lack of correlation with inhibitory potency. Overall, the balanced multifunctional profiles of these hybrids render them potentially promising candidates for treating AD, thus deserving further investigation. Full article

Increased consumer awareness on food safety has spurred the development of detection techniques for pesticide residues. In this study, a rapid detection card on the basis of enzyme action was developed for the visual detection of pesticides, in which the thermally crosslinked and surface-decorated polyvinyl alcohol/citric acid nanofiber mat (PCNM) was employed as a novel immobilization matrix for acetylcholinesterase (AChE). The PCNM, crosslinked at 130 °C for 50 min, exhibited appropriate microstructure and water stability, making it suitable for AChE immobilization. The activation of carboxyl groups by surface decoration resulted in a 2.5-fold increase in enzyme loading capacity. Through parameter optimization, the detection limits for phoxim and methomyl were determined to be 0.007 mg/L and 0.10 mg/L, respectively. The detection card exhibited superior sensitivity and a reduced detection time (11 min) when compared to a commercially available pesticide detection card. Furthermore, the detection results of pesticide residues in fruit and vegetable samples confirmed its feasibility and superiority over commercial alternatives, suggesting its great potential for practical application in the on-site detection of pesticide residues. Full article

The present study investigated the neuroprotective potential of the Murraya carbazole derivatives murrayanol, mahanimbine, murrayafoline A, and 9-methyl-9H-carbazole-2-carbaldehyde using in silico and in vitro assays. The pharmacokinetic properties and potential toxicity (ADME/T) of the carbazole derivatives were assessed to evaluate their prospects as up-and-coming drug candidates. Molecular docking was used to investigate the interactions of the compounds with Aβ (PDB: 1IYT, 2BEG, and 8EZE) and AChE receptors (PDB: 4EY7 and 1C2B). The results from the in vitro assays were used to validate and support the findings from the in silico assays. The compounds demonstrated significant inhibition of acetylcholinesterase (AChE), a key target in neurodegenerative disorders. Murrayanol and mahanimbine presented superior inhibitory activity (IC₅₀ ~0.2 μg/mL), outperforming the reference drug, galantamine. The inhibition mechanisms were competitive (murrayanol, murrayafoline A, and 9-methyl-9H-carbazole-2-carbaldehyde) and non-competitive (mahanimbine), supported by low Ki values and strong docking affinities. The compounds also proved effective in reducing Aβ fibrillization (murrayanol: 40.83 ± 0.30%; murrayafoline A: 33.60 ± 0.55%, mahanimbine: 27.68 ± 2.71%). These findings highlight Murraya carbazoles as promising scaffolds for multifunctional agents in AD therapy. Further optimization and mechanistic studies are warranted to advance their development into clinically relevant neuroprotective agents. Full article

Black Chiloe’s giant garlic is a functional food produced by a mild Maillard reaction that contains relevant bioactive molecules like organosulfur compounds (OSCs) and (poly)phenols (PPs). Compared with raw garlic, black garlic has a higher content of PPs and S-allyl cysteine (SAC), a key OSC due to its bioactivities. The objective of the present work was to optimize by chemometric tools a green microwave-assisted extraction (MAE) of SAC and PPs present in black Chiloe’s giant garlic to detect and identify novel bioactive molecules with antioxidant and/or inhibitory activities over cyclooxygenase, α-glucosidase, and acetylcholinesterase enzymes. The MAE factors were optimized using a central composite design, establishing optimal PP and SAC yields at 67 °C, 0% ethanol, 12 min and 30 °C, 40% ethanol, 3 min, respectively. PP and SAC values were 9.19 ± 0.18 mg GAE/g DW and 2.55 ± 0.10 mg SAC/g DW. Applying effect-directed analysis using high-performance thin layer chromatography-bioassay and mass spectrometry, the bioactive molecules present in the MAE extract with antioxidant and inhibitory activities over cyclooxygenase, α-glucosidase, and acetylcholinesterase enzymes were identified as N-fructosyl-glutamyl-S-(1-propenyl)cysteine, N-fructosyl-glutamylphenylalanine, and Harmane. Full article

The search for selective anticholinergic agents stems from varying cholinesterase levels as Alzheimer’s Disease progresses from the mid-to-late stage and from butyrylcholinesterase’s (BChE) role in β-amyloid plaque formation. While structure-based and pharmacophore-based virtual screening could search from large libraries in a short time, these methods do not consider dynamic features that result from a ligand’s inhibition of the enzyme and consequently may under- or overexaggerate enzyme selectivity of a given ligand. In this computational study, we probed the selectivity of representative secondary metabolite compounds against acetylcholinesterase and BChE through molecular dynamics simulations. The results were evaluated by analysis of the root mean squared deviation of ligand heavy atoms, the radius of gyration of each inhibited and uninhibited enzyme, root mean squared fluctuation of residues, intermolecular interaction energy, and linear interaction energy approximation of the Gibbs free energy of binding. These considerations further reveal the induced-fit characteristics contributing to ChE selectivity that are predominantly due to the greater flexibility of BChE’s active site gorge. Full article

Donepezil (DPZ) is an Alzheimer’s disease (AD) drug that promotes cholinergic neurotransmission and exhibits excellent acetylcholinesterase (AChE) selectivity. The current oral formulations of DPZ demonstrate decreased bioavailability, attributed to limited drug permeability across the blood–brain barrier (BBB). In order to overcome these limitations, various dosage forms aimed at delivering DPZ have been explored. This discussion will focus on the nose-to-brain (N2B) delivery system, which represents the most promising approach for brain drug delivery. Intranasal (IN) drug delivery is a suitable system for directly delivering drugs to the brain, as it bypasses the BBB and avoids the first-pass effect, thereby targeting the central nervous system (CNS). Currently developed formulations include lipid-based, solid particle-based, solution-based, gel-based, and film-based types, and a systematic review of the N2B research related to these formulations has been conducted. According to the in vivo results, the brain drug concentration 15 min after IN administration was more than twice as high those from other routes of administration, and the direct delivery ratio of the N2B system improved to 80.32%. The research findings collectively suggest low toxicity and high therapeutic efficacy for AD. This review examines drug formulations and delivery methods optimized for the N2B delivery of DPZ, focusing on technologies that enhance mucosal residence time and bioavailability while discussing recent advancements in the field. Full article

Background: Pharmaceutical compounds frequently co-occur in environmental waters, but studies on their combined effects on animals and humans remain limited. The present study investigated the individual and combined short-term effects of ketoprofen (Kp, a nonsteroidal anti-inflammatory drug inhibiting cyclooxygenase-2), valproic acid (VPA, an anticonvulsant acting as a voltage-gated sodium channel modulator), and meropenem (Mp, a β-lactam antibiotic) at environmentally relevant concentrations on zebrafish behavior, acetylcholinesterase (AChE) activity, and oxidative status. Methods: Adult zebrafish were exposed for 4 days to Kp, VPA, Mp, and their binary and ternary mixtures. Behavioral effects were assessed using 3D novel tank and social behavior tests, while the oxidative stress response was assessed through malondialdehyde (MDA) content, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities. Results: Zebrafish exposed to Mp showed a notable increase in immobility, whereas those exposed to VPA and Mp + Kp exhibited a significant augmentation of average velocity and counter-clockwise rotations. All treated groups exhibited a notable increase in the time spent near the walls (thigmotaxis), and except for the control and Mp-exposed zebrafish, the other groups mostly stayed in the bottom tank zone (geotaxis). Kp, VPA + Kp, and VPA + Mp + Kp treatments impaired social behavior, with zebrafish displaying less interest in conspecifics. Biochemical analysis demonstrated that both the individual drugs and their combination caused oxidative stress, characterized by decreased GPx activity and increased SOD activity and MDA levels. Moreover, AChE activity was more strongly inhibited in zebrafish exposed to the binary and ternary mixtures than to individual drugs. Conclusions: The results indicate that acute exposure to individual and/or combined pharmaceuticals induces behavioral changes, oxidative damage, and AChE inhibition in zebrafish, highlighting the need to assess the effects of pharmaceutical mixtures for comprehensive ecosystem risks evaluation. Full article

Alzheimer’s disease (AD) is a prevalent neurodegenerative disorder with a pressing need for novel therapeutics. However, current medications only offer symptomatic relief, without tackling the underlying pathology. To explore the bioactive potential of marine-derived fungi, this study focused on Aspergillus terreus C23-3, a strain isolated from the coral Pavona cactus in Xuwen County, China, which showed a richer metabolite fingerprint among the three deposited A. terreus strains. AntiSMASH analysis based on complete genome sequencing predicted 68 biosynthetic gene clusters (BGCs) with 7 BGCs synthesizing compounds reported to have anti-AD potential, including benzodiazepines, benzaldehydes, butenolides, and lovastatin. Liquid chromatography coupled with mass spectrometry (LC-MS)-based combinational metabolomic annotation verified most of the compounds predicted by BGCs with the acetylcholinesterase (AChE) inhibitor territrem B characterized from its fermentation extract. Subsequently, molecular docking showed that these compounds, especially aspulvione B1, possessed strong interactions with AD-related targets including AChE, cyclin-dependent kinase 5-p25 complex (CDK5/p25), glycogen synthase kinase-3β (GSK-3β), and monoamine oxidase-B (MAO-B). In conclusion, the genomic–metabolomic analyses and molecular docking indicated that C23-3 is a high-value source strain for anti-AD natural compounds. Full article

Cholinergic neuron impairment is a significant cause of cognitive decline in Alzheimer’s disease (AD), making acetylcholinesterase (AChE) a key therapeutic target. AChE inhibitors are principal drugs prescribed to alleviate symptoms in AD patients, while up to 50% of these individuals also suffer from depression, frequently treated with selective serotonin reuptake inhibitors (SSRIs). Due to the multisymptomatic nature of AD, there is a growing interest in developing multitargeted ligands that simultaneously enhance cholinergic and serotonergic tone. This study presents the synthesis of novel ligands based on functionalized piperidines, evaluated through radioligand binding assays at the serotonin transporter (SERT) and AChE and butyrylcholinesterase (BuChE) inhibition. The pharmacological results showed that some compounds exhibited moderate inhibitory activity against AChE, with one compound 19 standing out as the most potent, also displaying a moderate BuChE inhibitory activity, while showing low affinity for SERT. On the other hand, compound 21 displayed an interesting polypharmacological profile, with good and selective activity against BuChE and SERT. The results underscore the difficulty of designing promiscuous ligands for these targets and suggest that future structural modifications could optimize their therapeutic potential in AD. Full article