Search Results (579)

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

Alzheimer’s disease (AD) is a multi-factorial neurodegenerative disease with a complex pathomechanism that can be best treated with multi-target medications. Among the possible molecular targets involved in AD, acetylcholinesterase (AChE) and monoamine oxidase B (MAO-B) are well recognized because they control the neurotransmitters responsible for memory processes. This review discusses the current understanding of AD pathology, recent advances in AD treatment, and recent reports in the field of dual AChE/MAO-B inhibitors for treating AD. We provide a classification of dual inhibitors based on their chemical structure and describe active compounds belonging to, i.a., chalcones, coumarins, chromones, imines, and hydrazones. Special emphasis is given to the computer-aided strategies of dual inhibitors design, their structure–activity relationships, and their interactions with the molecular targets at the molecular level. Full article

Background/Objectives: The need for dual-targeted enzyme inhibitors is critical in addressing complex diseases like Alzheimer’s and glaucoma. Imidazothiadiazole and chalcone moieties are known for diverse bioactivities. This study aimed to develop novel imidazothiadiazole–chalcone hybrids as potential inhibitors of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase isoforms (hCAs), specifically hCA I and hCA II. Methods: Four hybrid molecules (8a–8d) were synthesized and structurally confirmed via ¹H NMR, ¹³C NMR, FT-IR, MS, and elemental analysis techniques. Their enzyme inhibitory activities were assessed using Ellman’s and Verpoorte’s methods. Molecular docking and 100 ns molecular dynamics (MD) simulations were conducted to examine binding interactions. Absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties were predicted using the pkCSM platform. Results: All compounds showed strong enzyme inhibition: AChE (K_i: 3.86–11.35 nM), BChE (K_i: 1.01–1.78 nM), hCA I (K_i: 45.13–81.24 nM), and hCA II (K_i: 36.08–52.45 nM). Docking analyses confirmed favorable binding, particularly with active-site residues. MD simulations demonstrated stable interactions throughout 100 ns. Compound 8a exhibited the highest cholinesterase inhibition, while compounds 8d and 8c were the most potent against hCA I and hCA II, respectively. The ADMET results showed high absorption and acceptable safety, with mild mutagenicity or cardiotoxicity concerns in select compounds. Conclusions: These findings suggest that imidazothiadiazole–chalcone hybrids are promising multi-target enzyme inhibitors. Their potent activity, structural stability, and pharmacokinetic potential support their further development for therapeutic use in neurodegenerative and ocular diseases. Full article

Neurodegenerative diseases (NDDs), including Alzheimer’s disease (AD) and Parkinson’s disease (PD), are characterized by progressive neuronal dysfunction and loss and represent a significant global health challenge. Oxidative stress, neuroinflammation, and neurotransmitter dysregulation, particularly affecting acetylcholine (ACh) and monoamines, are key hallmarks of these conditions. The current therapeutic strategies targeting cholinergic and monoaminergic systems have some limitations, highlighting the need for novel approaches. Metallodrugs, especially ruthenium and platinum complexes, are gaining attention for their therapeutic use. Among metal complexes, gold(I) and silver(I) N-heterocyclic carbene (NHC) complexes exhibit several biological activities, but their application in NDDs, particularly as monoamine oxidase (MAO) inhibitors, remains largely unexplored. To advance the understanding of this field, we designed, synthesized, and evaluated the biological activity of a new series of Au(I) and Ag(I) complexes stabilized by NHC ligands and bearing a carboxylate salt of tert-butyloxycarbonyl (Boc)-N-protected proline as an anionic ligand. Through in silico and in vitro studies, we assessed their potential as acetylcholinesterase (AChE) and MAO inhibitors, as well as their antioxidant and anti-inflammatory properties, aiming to contribute to the development of potential novel therapeutic agents for NDD management. Full article

(−)-Patagonic acid (1) is a clerodane diterpene isolated from several plants from the Alismataceae, Asteraceae, Euphorbiaceae, Fabaceae, Lamiaceae, Salicaceae, Sapindaceae, and Velloziaceae families, and its biological potential as an inhibitor of butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) and as an anti-inflammatory compound has been described. Furthermore, the enantiomer (+)-1 is also described in Fabaceae and Verbenaceae. A lack of formal studies about the absolute configuration (AC) determination of 1 is emphasized. Thus, the present manuscript describes the AC determination of patagonic acid (1). The chemical correlation of (−)-1 from (−)-hardwickiic acid (2) was achieved by a simplistic oxidative process. The specific rotation value and electronic circular dichroism (ECD) analysis allowed for the AC determination of (−)-1 as (5R,8R,9S,10R)-(−)-patagonic acid. ECD revealed a positive exciton chirality (EC) phenomenon in both (−)-1 and (−)-2, which is directly associated with their configuration and conformational preferences, which were assessed by DFT calculations at the B3LYP/DGDZVP level of theory. Since the NMR data of (+)-1 are fully coincident with those from its enantiomer studied herein, the chirality of (5S,8S,9R,10S)-(+)-patagonic acid could also be determined. These experimental conclusions deeply complement the literature related to clerodane compounds biosynthesized in several families of plants of scientific interest. Full article

Background and Objectives: Methotrexate (MTX) is a widely utilised pharmaceutical agent in the treatment of various malignancies and inflammatory diseases. However, its clinical utility is often constrained by its potential for hepatotoxicity. Although pyridostigmine is a well-established reversible acetylcholinesterase inhibitor, its potential therapeutic role in preventing hepatic injury remains incompletely defined. The present study aimed to investigate whether pyridostigmine provides protective effects against MTX-triggered liver damage in a rat model. Methods: Thirty-six female Wistar albino rats randomly assigned to three groups: control (n = 12), MTX + saline (n = 12), and MTX + pyridostigmine (n = 12). Hepatotoxicity was induced by a single-dose MTX injection (20 mg/kg), followed by daily oral administration of either pyridostigmine (5 mg/kg) or saline for ten consecutive days. Hepatic function markers, oxidative stress parameters, fibrosis-associated mediators, and histopathological changes were assessed. Results: Pyridostigmine significantly attenuated MTX-induced elevations in plasma alanine aminotransferase (p < 0.05) and cytokeratin-18 levels (p < 0.001), and reduced liver and plasma malondialdehyde (MDA) levels (p < 0.05). Additionally, pyridostigmine treatment resulted in reduced levels of transforming growth factor-beta (p < 0.05), bone morphogenetic protein-9 (p < 0.001), and endoglin levels (p < 0.05), as well as increased sirtuin 1 level (p < 0.05). Histopathological examination revealed that pyridostigmine treatment significantly reduced MTX-induced hepatocyte necrosis, fibrosis, and cellular infiltration. Conclusions: Pyridostigmine exerted hepatoprotective effects against MTX-induced liver injury by attenuating oxidative stress, restoring SIRT1 expression, and suppressing pro-fibrotic signaling. These findings indicate that pyridostigmine may hold therapeutic potential for the prevention of MTX-associated hepatotoxicity. Full article

Current therapies for Alzheimer’s disease (AD) includes acetylcholinesterase inhibitors, NMDA receptor antagonists, and amyloid beta (Aβ)/Tau-targeting drugs. While these drugs improve cognitive decline and target the pathological mechanisms, their outcomes still are still in debate. Mesenchymal stem cells (MSCs) offer a regenerative approach by modulating neuroinflammation and promoting neuroprotection. Although the paracrine of MSCs is efficient in various AD preclinical studies and the exosomes of MSCs have entered clinical trials, the key cytokines driving the efficacy remain unclear. Here, we evaluated human umbilical cord-derived MSCs (hUC-MSCs) and employed gene-silenced MSCs (siHGF-MSCs, siTNFR1-MSCs, siBDNF-MSCs) in APP/PS1 AD mice to investigate specific mechanisms. hUC-MSCs significantly reduced Aβ/Tau pathology and neuroinflammation, with cytokine-specific contributions: silencing HGF predominantly reduced Aβ/Tau clearance, although silencing TNFR1 or BDNF showed modest effects; silencing TNFR1 or BDNF more prominently weakened anti-neuroinflammation, while silencing HGF exerted a weaker influence. All three cytokines partially contributed to oxidative stress reduction and cognitive improvements. Our study highlights MSC-driven AD alleviation as a multifactorial strategy and reveals specific cytokines alleviating different aspects of AD pathology. Full article

The incorporation of selenium into tacrine derivatives has been explored as a novel strategy to enhance therapeutic efficacy while minimizing toxicity in the treatment of neurodegenerative diseases such as Alzheimer’s. This study utilized computational and experimental approaches, including Density Functional Theory (DFT), molecular docking, pharmacokinetic profiling, and toxicological predictions, to evaluate the potential of these derivatives. The selenium-modified compounds demonstrated improved electronic properties, such as narrower HOMO–LUMO gaps and optimized electronegativity, resulting in enhanced stability and reactivity. Pharmacokinetic analyses revealed favorable absorption, distribution, and blood–brain barrier penetration, while toxicological assessments indicated reduced hepatotoxicity and skin sensitization risks compared to tacrine. Molecular docking and dynamic simulations highlighted strong and stable interactions of the derivatives with critical enzymes, including acetylcholinesterase (AChE) and beta-secretases (BACE1 and BACE2). Compounds 12 and 13, in particular, emerged as the most promising candidates due to their superior stability and binding affinity. These findings underscore the potential of selenium-modified tacrine derivatives as safer and more effective therapeutic agents for Alzheimer’s disease, warranting further experimental validation. Full article

This manuscript reports the synthesis and characterization of 19 novel heterostilbene carbamates, designed as selective butyrylcholinesterase (BChE) inhibitors with potential applications in the treatment of neurodegenerative disorders, particularly Alzheimer’s disease. The compounds were synthesized from resveratrol analogs, and their structures were confirmed by NMR spectroscopy, high-resolution mass spectrometry (HRMS), and single-crystal X-ray diffraction for selected derivatives (compounds 1 and 4). In vitro assays demonstrated high selectivity toward BChE over acetylcholinesterase (AChE), with compound 16 exhibiting exceptional inhibitory activity (IC₅₀ = 26.5 nM). Furthermore, compound 16 showed moderate anti-inflammatory effects by inhibiting LPS-stimulated TNF-α production in peripheral blood mononuclear cells. In silico ADME(T) profiling revealed favorable pharmacokinetic properties and low mutagenic potential for the majority of compounds. Molecular docking and molecular dynamics simulations confirmed stable binding interactions within the BChE active site. These results highlight heterostilbene carbamates as promising lead structures for developing novel therapeutic agents targeting neurodegenerative diseases. Full article

Schistosomiasis is a parasitic disease caused by helminth parasites of the genus Schistosoma, affecting >200 million people worldwide. Current schistosomiasis treatment relies on a single drug, praziquantel, highlighting the urgent need for new therapies. We have identified a non-neuronal tegumental acetylcholinesterase from Schistosoma mansoni (SmTAChE) as a rational and molecularly defined drug target. Molecular modeling reveals significant structural differences between SmTAChE and human AChE, suggesting the potential for identifying parasite-specific inhibitors. Here, we screened recombinant SmTAChE (rSmTAChE) against two chemical libraries: the Broad Institute Drug Repurposing Hub (5440 compounds) and the Diversity-Oriented Synthesis (DOS)-A library (3840 compounds). High-throughput screening identified 116 hits from the Repurposing Hub (2.13% hit rate) and 44 from the DOS-A (1.14% hit rate) library that inhibited rSmTAChE ≥60% at 20 µM. Dose–response assays using both rSmTAChE and recombinant human AChE (rHsAChE) revealed 19 Repurposing Hub compounds (IC₅₀: 0.4–24 µM) and four DOS-A scaffolds (IC₅₀: 13–29 µM), with higher selectivity for rSmTAChE. Selective inhibitors such as cepharanthine, primaquine, mesalazine, and embelin emerged as promising candidates for further evaluation in schistosomiasis treatment. These 23 newly identified selective hits provide a foundation for the further development of novel anti-schistosome therapies. Full article

Alzheimer’s disease (AD) is considered one of the main pathologies of our time, whose incidence and prevalence are suggested to be strongly underestimated. AD presents as a complex neurodegenerative condition characterized by marked neuroinflammation and a significant decline in the cognitive and mnemonic functions of affected patients. Recognized AD pathological hallmarks include amyloid beta plaque and neurofibrillary tangle formation, synaptic dysfunction with considerable apoptosis of cholinergic and dopaminergic neurons, and high levels of oxidative stress and neuroinflammation. The available pharmacological treatments are represented by acetylcholinesterase inhibitors to treat the mild to moderate form of the disease and N-methyl-D-aspartate inhibitors alone or in combination with the previously cited ones in the late stage of the neurodegenerative condition. Furthermore, emerging drug therapies such as monoclonal antibodies are promising agents in AD management. Although scientific evidence highlights these chemicals as effective in slowing down disease progression, significant limitations behind their employment derive from the notable dose-dependent side effects and the single-target mechanism of action. In this context, two well-studied phytotherapeutics, W. somnifera (W. somnifera) and fungi belonging to the genus Cordyceps, have gained attention for their chemical composition regarding their neuroprotective and anti-inflammatory effects. Ashwagandha (obtained principally from the roots of W. somnifera) is an adaptogen that relieves stress and anxiety. It contains several ergostane-type steroidal lactones—such as withanolides and withaferin A—and various alkaloids, contributing to its antioxidant and neuroprotective effects. Likewise, cordycepin is the main bioactive principle found in Cordyceps fungi. This natural nucleoside has been reported to possess therapeutic potential as an anti-cancer, immunomodulatory, and anti-inflammatory agent, with some studies suggesting a beneficial role in AD treatment. The purpose of the present review is to investigate the pharmacological properties of W. somnifera and Cordyceps species in the context of AD treatment and explore the therapeutic potential of the constitutive bioactive molecules in preclinical models mimicking this neurodegenerative condition. Full article

Alzheimer’s disease (AD) is the most common neurodegenerative disease which has a rather complex pathophysiology. During its course, several neurotransmitter neuronal systems get affected such as acetylcholinergic, glutamatergic, gamma-aminobutyric acid (GABA)ergic systems, etc. Such complex physiology requires a sophisticated approach to pharmaceutical management. Therefore, multi-target drugs seem to be an appealing solution. In the present study, we designed and synthesized a hybrid molecule—N-sinapoylamide of memantine, whose parent molecules memantine (MEM) and sinapic acid have been shown in vivo to impact glutamatergic, acetylcholinergic, and GABA-ergic systems, respectively. In silico comparative testing of these molecules was performed, their patterns of interaction with the target enzymes or molecular complexes were analyzed, and some of the mechanisms of action were proposed. Consequently, in vivo testing was performed on a scopolamine mice model of AD and the results overly confirm part of the in silico findings. Therefore, the hybrid molecule (N-Sinapoyl-memantine) seems to be a potent candidate for further evaluation in the management of AD. Full article

Neurological disorders, encompassing neurodegenerative and neuroinflammatory conditions, present significant public health and clinical challenges. Recent research has elucidated the pivotal role of various enzymes in the onset and progression of these disorders. This review explores the therapeutic potential of targeting these enzymes with natural and synthetic molecules. Key enzymes, including acetylcholinesterase, monoamine oxidase, beta-secretase, tau kinases, caspases, and cyclooxygenase-2, are implicated in diseases such as Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis. Modulating these enzymes can alleviate symptoms, slow disease progression, or reverse pathological changes. Natural molecules derived from plants, microbes, seaweeds, and animals have long been noted for their therapeutic potential. Their ability to interact with specific enzymes with high specificity and minimal side effects makes them promising candidates for treatment. These natural agents provide a foundation for developing targeted therapies with improved safety profiles. Simultaneously, the development of synthetic chemistry has resulted in molecules designed to inhibit neurodegenerative enzymes with precision. This review examines the progress in creating small molecules, peptides, and enzyme inhibitors through sophisticated drug design techniques. It evaluates the efficacy, safety, and mechanisms of these synthetic agents, highlighting their potential for clinical application. The review offers a comprehensive overview of recent advancements in enzyme-targeted therapies for neurological disorders, covering both natural and synthetic molecules investigated in preclinical and clinical settings. It discusses the mechanisms through which these molecules exert their effects, the challenges faced in their development, and future research directions. By synthesizing current knowledge, this paper aims to illuminate the potential of enzyme-targeted interventions in managing neurological disorders, showcasing both the promise and limitations of these approaches. Full article

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, amyloid-β (Aβ) deposition, tau hyperphosphorylation, oxidative stress, and chronic neuroinflammation. Growing evidence highlights neuroinflammation—driven by microglial activation and pro-inflammatory cytokine release—as a key contributor to AD pathogenesis and progression. In the absence of effective disease-modifying therapies, attention has turned to natural compounds with multi-target potential. Flavonoids, a diverse class of plant-derived polyphenols, have demonstrated neuroprotective properties through antioxidant activity, modulation of neuroinflammatory pathways, and interference with both Aβ aggregation and tau pathology. This narrative review provides an integrative overview of current findings on the mechanisms of action of key flavonoids—such as quercetin, luteolin, and apigenin—in both preclinical and clinical models. Emphasis is placed on their effects on microglial polarization, oxidative stress reduction, mitochondrial support, and synaptic function enhancement. Moreover, flavonoids show synergistic potential when combined with standard pharmacotherapies, such as acetylcholinesterase inhibitors, and may offer broader cognitive benefits in patients with mild cognitive impairment (MCI). Despite these promising findings, significant challenges persist, including poor bioavailability, inter-individual variability, and limited long-term clinical data. This review identifies critical gaps in knowledge and outlines future directions, including targeted drug delivery systems, biomarker-guided personalization, and long-duration trials. Flavonoids thus emerge not only as promising neuroprotective agents but also as complementary candidates in the development of future multi-modal strategies for AD treatment. Full article