Frailty is a common and debilitating feature of Alzheimer's disease (AD), yet effective therapeutic strategies targeting both cognitive decline and physical frailty remain limited. Qi-Fu-Yin (QFY), a traditional Chinese herbal formulation, has been used to treat aging-related disorders, but its effects on frailty in AD and the underlying mechanisms are unclear. This study aimed to evaluate whether QFY alleviates frailty in 5xFamilial Alzheimer's Disease (FAD) transgenic mice and to explore the potential involvement of gut microbiota and neuroendocrine hormones. Mice were treated with QFY at low (2.8 g/kg), medium (5.6 g/kg), or high (11.2 g/kg) doses, or with donepezil as a positive control, for 194 days. Frailty-related behaviors were assessed using CatWalk gait analysis, grip strength, rotarod, nest-building, and aging scoring. Plasma hormone levels were measured, and fecal gut microbiota composition and function were analyzed by 16S rRNA sequencing and metagenomic analysis. QFY treatment significantly improved gait parameters, grip strength, motor coordination, nesting ability, and reduced aging scores in 5xFAD mice, with effects comparable to or superior to those of donepezil. QFY also restored aberrant levels of estradiol, testosterone, and corticosterone, and reshaped gut microbiota composition, particularly by increasing the abundance of Adlercreutzia, which negatively correlated with senescence and testosterone levels. Functional metagenomics revealed that QFY partially restored disease-associated microbial pathways, including those involved in carbohydrate metabolism and virulence. These findings suggest that QFY alleviates frailty in 5xFAD mice, with effects associated with concurrent modulation of gut microbiota and neuroendocrine function, though causal relationships require further validation. These findings support further investigation of QFY as a potential intervention for AD-associated frailty.

Alzheimer's disease (AD) affects over 55 million individuals worldwide, yet approved pharmacotherapies remain limited to symptomatic relief. Dual inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) offers a validated approach to restoring cholinergic tone. However, structurally differentiated inhibitors with favorable selectivity profiles are critically needed. Here, we report a series of pyrimidine clubbed thiazolo[4,5-c]isoxazole framework that functions as potent dual cholinesterase inhibitors with low-micromolar activity against both AChE and BuChE. Lead compound-1 demonstrated IC50 values of 6.19 ± 0.60 μM (AChE) and 8.64 ± 0.91 μM (BuChE) showing promising performance over the reference donepezil (AChE IC50 = 19.38 ± 0.98 μM, BuChE IC50 = 27.54 ± 1.34 μM). Furthermore, structure-activity relationship analysis identified electron-withdrawing (p-CF3, p-F, o,p-Cl, p-NO2) and electron-donating (-OH) aryl substituents as principal modulators of inhibitory potency. Moreover, molecular docking against human AChE and BuChE crystal structures revealed dual engagement of the catalytic anionic site and peripheral anionic site through hydrogen-bonding and π-π stacking interactions. In silico ADMET profiling confirmed electronic reactivity and drug-likeness of lead compounds. These findings establish pyrimidine-clubbed thiazolo[4,5-c]isoxazole as a mechanistically grounded scaffold with translational potential for next-generation anti-Alzheimer therapeutics.

Cholinergic dysfunction is a key feature of cognitive impairment, and currently available acetylcholinesterase (AChE) inhibitors provide limited symptomatic benefit and are often associated with adverse effects. This study evaluated the cognitive-protective effects of bavachin (BVC), a prenylated flavonoid from Psoralea corylifolia, and its interaction with Donepezil (DNP) in a scopolamine (SCP)-induced amnesia model. Male Swiss albino mice were pretreated with BVC (10-40 mg/kg), DNP (2.5 mg/kg), or their combination for 7 days prior to SCP challenge, followed by assessment using multiple behavioral paradigms, including novel object recognition, elevated plus maze, passive avoidance, Y-maze, and Morris water maze. BVC attenuated SCP-induced memory deficits in a dose-dependent manner, with the 40 mg/kg dose producing performance statistically comparable to, though not formally demonstrated to be equivalent to, the normal control across tests. Bliss independence analysis of behavioral endpoints indicated predominantly additive interactions, with occasional greater-than-additive trends. Biochemical evaluation demonstrated that BVC inhibits AChE in vitro (IC50 = 27.7 µM) and attenuates SCP-induced elevations of AChE activity ex vivo in the frontal cortex and hippocampus. Combination treatment showed a greater-than-additive interaction in the frontal cortex (ΔBliss = 0.054) and an approximately additive effect in the hippocampus (ΔBliss = 0.013). Molecular docking and molecular dynamics simulations further suggested stable binding of BVC within the active sites of AChE and butyrylcholinesterase (BChE). Collectively, these findings indicate that BVC attenuates cognitive deficits, at least in part, through cholinesterase inhibition, and exhibits additive effects with DNP, supporting its potential as an adjunctive candidate for cognitive disorders.

Alzheimer's disease (AD) affects more than 55 million people worldwide, yet no disease-modifying therapy has been approved. Here, 23 phytochemicals from Olea europaea (olive) were evaluated using a multi-filter pipeline comprising ADME/drug-likeness screening, BBB permeability assessment, molecular docking, DFT analysis, and MD simulations. This is the first computational study of olive phytochemicals targeting AChE to use BBB permeability as an explicit screening filter, addressing the CNS penetrance gap that limits translation of prior in silico hits. ADME screening (through SwissADME) identified three Lipinski-compliant, BBB-permeable candidates. Among these, 4-ethylguaiacol exhibited the strongest AChE binding (-7.0 kcal/mol) and a favorable HOMO-LUMO energy gap (6.09 eV), indicating moderate chemical reactivity and stability. Structure-guided optimization of 4-ethylguaiacol using RDKit led to the design of AM-11; 4-ethyl-5-(1-hydroxycyclopropyl)-2-methoxyphenol, whose C-5 hydroxycyclopropyl group forms direct hydrogen bond with catalytic residue, Ser203. AM-11 showed improved binding affinity (-7.9 kcal/mol), stable RMSD throughout a 100 ns MD simulation, and a predicted LD50 of 720 mg/kg (Class IV), a better acute toxicity profile than donepezil (505 mg/kg). These findings position AM-11 as a as a computational lead for a BBB-permeable AChE inhibitor scaffold requiring experimental validation, and the pipeline as a reproducible framework for phytochemical-based lead optimization in AD.

Protein-drug interactions are one of the fundamental processes determining the biological effects of drugs, and they mostly occur via weak interactions such as van der Waals forces, hydrogen bonds, and ionic bonds. In this study, the binding interaction between Donepezil (DPZ) and Bovine Serum Albumin (BSA) was investigated using Electrochemical Impedance Spectroscopy (EIS), a sensitive and rapid method, and the interfacial changes resulting from drug-protein complex formation were evaluated by monitoring the charge transfer resistance (RCT). Given the limited number of studies in the literature that utilize the EIS method, this study has the potential to fill a significant gap in protein-drug interaction research. This study developed a simple, label-free, electrochemical impedance spectroscopy-based approach that allows direct measurement in solution. Using a Pencil Graphite Electrode (PGE), binding was characterized through changes in charge transfer resistance in a system containing DPZ and BSA. Responses related to interaction with BSA were recorded at increasing DPZ concentrations by optimizing pH and incubation time. The findings demonstrate that impedance measurements are an effective method for directly and accurately monitoring drug-protein interactions. Furthermore, the findings obtained for the DPZ-BSA interaction using RCT were confirmed by UV-Vis spectrophotometry and Isothermal Titration Calorimetry (ITC).

Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder involving mainly cholinergic dysfunction, protein misfolding, and metal dyshomeostasis. Considering the complexity of the pathology, multi-target approaches represent a valuable alternative to current approved mono-target treatments. In this study, starting from two previously identified lead compounds, fifteen new derivatives were designed. Various functional groups were introduced to evaluate their impact on cholinesterases (ChEs) and fatty-acid amide hydrolase (FAAH) and in some cases potent selective human acetylcholinesterase inhibition was observed (IC50 up to 9 ± 1 nM for compound 1 and 3). Among the series, the amine-based derivatives (9 and 11) were further evaluated for Fe[3+], Cu[2+], and Zn[2+] chelation ability, under a metal targeted strategy, showing high selectivity (pFe[3+] = 16.1, pCu[2+] = 11.0 and pZn[2+] = 6.03 for compound 11) and a metal-binding pattern suitable for anti-AD activity. Additionally, these molecules exhibited noteworthy antioxidant properties (IC50 = 17-45 μM for compounds 9-11), thus potentially beneficial in overcoming ROS overproduction typical of the disease. Finally, the whole series was subjected to an extensive in vitro ADME-related profiling, showing promising experimental ADME-related properties.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by pathological aggregation of amyloid-β (Aβ) and tau proteins, representing two major hallmarks of disease progression. Targeting both aggregation pathways simultaneously offers a promising therapeutic strategy. Building upon our previous identification of the α-ketoamide derivative BD23 as a dual aggregation modulator, we report the rational design, synthesis, and biological evaluation of a new series of indole-piperazine based α-ketoamide moiety. A focused library of twenty-four compounds was synthesized and characterized using nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HRMS). These compounds were evaluated for modulation of Aβ42 aggregation using the thioflavin T fluorescence assay. Several derivatives significantly altered fibrillization kinetics, with MD03, MD07, MD08, and MD10 emerging as the most active candidates. Among them, MD08 exhibited optimal aqueous solubility (0.037 ± 0.0035 mg/mL) along with moderate blood-brain barrier permeability (Pe = 3.42 ± 0.33 × 10[-6] cm/s). Further evaluation demonstrated that MD08 inhibited heparin-induced tau aggregation in vitro, without cytotoxicity in human neuroblastoma (SH-SY5Y) cells. In vivo studies in an Aβ-induced cognitive decline mouse model revealed significant cognitive improvement in a dose-dependent manner (2, 5, and 10 mg/kg), with the highest dose showing efficacy comparable to the standard drug donepezil. Complementary in silico studies, including molecular docking and molecular dynamics simulations, supported stable interactions with Aβ and tau. Collectively, these findings identify MD08 as a promising dual aggregation modulator for AD, warranting further preclinical investigation.

Despite isolated REM sleep behaviour disorder (iRBD) reliably identifying individuals at high risk of developing Parkinson's disease (PD) or dementia with Lewy bodies (DLB), with more than 90% converting, the neurobiological markers of the conversion phenotype are not fully understood. Most previous studies have found univariate imaging biomarkers of phenoconversion, and most of these lack specificity for PD and DLB. Using a well-characterised iRBD cohort (N=21), receiving multiple PET and MRI scans, we aimed to assess if the inter-modality relationship can specifically predict conversion to PD or DLB. The patients received [[18]F]-DOPA, [[11]C]-Donepezil and [[11]C](R)-PK11195 PET and structural MRI scans to derive grey matter (GM) volume along with dynamic susceptibility contrast MRI to extract measures of microcirculatory dysregulation. We used a multimodal adaptation of the scaled sub-profile model to identify patterns of multimodal covariance across the PET and MRI scans. We identified a multimodal network characterised by high neuroinflammation, cholinergic dysfunction, GM atrophy and microcirculatory dysfunction with the covariance pattern converging in the medial occipito-parietal cortex (OPC). The combined pathology from the OPC and striatal [[18]F]-DOPA uptake was able to specifically predict conversion into DLB (sub-distribution hazard ratio=38.68, 95% confidence interval: 7.545-198.3), and this survived correction for age and disease duration. These findings demonstrate the feasibility of integrating multiple modalities in risk assessment and suggest that posterior cortical pathology, along with striatal dopaminergic impairment, could hold predictive value for phenotype-specific conversion of iRBD patients, and that multiple pathological processes converge in this brain region.

BackgroundAlzheimer's disease (AD) remains a therapeutic challenge, and adding other agents to donepezil may offer additional benefits.ObjectiveThis network meta-analysis aimed to compare the efficacy of donepezil-based combination therapies versus donepezil monotherapy in patients with AD.MethodsWe searched PubMed, Embase, Cochrane Library and Web of Science up to October 2025 for randomized-controlled trials comparing donepezil plus another drug with donepezil alone. The primary outcomes were cognitive function [Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-cog)], behavioral function (Neuropsychiatric Inventory) and functional ability [Alzheimer's Disease Cooperative Study Activities of Daily Living (ADCS-ADL)]. A frequentist network meta-analysis was performed, and treatments were ranked by SUCRA (Surface under the cumulative ranking curve) values. Time-stratified analyses were also conducted.Results41 trials involving 9822 patients were included. Compared with placebo, several combinations significantly improved MMSE and ADAS-cog scores, with Don (Donepezil) + Mas (Masitinib) (97.5%, 92.9%), Don + NBP (DL-3-n-butylphthalide) (82.5%, 74.5%) and Don + DSC (Dengzhan shengmai capsule) (81.4%) ranking highest. For ADCS-ADL, Don + Mas (92.7%), Don + NBP (74.1%), and Don + DSC (77.1%) showed significant improvements. No combination was statistically superior to donepezil monotherapy for any outcome, but numerical trends favored combination therapy across all time windows. The certainty of evidence was mostly moderate to low.ConclusionsSeveral donepezil-based combination therapies, particularly those with masitinib, NBP, DSC, and memantine, are more effective than placebo in improving cognitive and functional outcomes in AD. Although direct comparisons with donepezil monotherapy did not reach statistical significance, consistent trends support the potential of add-on strategies. Longer-term trials are needed to confirm sustained benefits.