ID: 42406553
Title: EphB1-Mediated Transient Blood-Brain Barrier Opening Facilitates a Ferritin-Based Nanotherapeutic for Alzheimer's Disease.
Abstract: The treatment of Alzheimer's disease (AD) is severely hampered by the blood-brain barrier (BBB), which limits the delivery of therapeutic agents like donepezil (DPZ), an acetylcholinesterase inhibitor. While DPZ has multi-faceted benefits, its clinical efficacy is constrained by poor BBB penetration, requiring high doses that lead to significant side effects. To overcome this, we developed a brain-targeted nanotherapeutic utilizing apoferritin (AFn) nanoparticles loaded with DPZ (AFn-DPZ). We demonstrate that this platform, by binding to the EphB1 receptor on the blood-brain barrier, enables transient and reversible opening of the blood-brain barrier, thereby facilitating efficient and targeted drug delivery. Following intravenous administration in an AD mouse model, AFn-DPZ exhibited enhanced brain accumulation and sustained release of DPZ. This targeted delivery inhibited acetylcholinesterase activity, reduced amyloid plaque burden, alleviated neuroinflammation, attenuated oxidative damage, restored mitochondrial function, and upregulated the expression of brain-derived neurotrophic factor (BDNF). Consequently, AFn-DPZ treatment significantly improved cognitive performance compared to free DPZ. Our findings establish EphB1-mediated facilitation of BBB traversal as a promising strategy for enhancing nanotherapeutic delivery to the brain, offering a potent approach to address the complex pathology of AD.

ID: 42407324
Title: From DNA-encoded library (DEL) screening to in vivo validation: LILRB4 (ILT3)-targeted small molecules reprograms myeloid immune suppression.
Abstract: Alzheimer's disease (AD) remains a major unmet clinical challenge, with limited therapeutic strategies capable of effectively modulating neuroimmune dysfunction. Leukocyte immunoglobulin-like receptor B4 (LILRB4/ILT3) has recently emerged as an inhibitory microglial immune checkpoint implicated in ApoE-mediated suppression of amyloid-β (Aβ) clearance and inflammatory signaling, supporting its potential as a therapeutic target in AD. Here, we applied DNA-encoded library (DEL) screening of approximately 3.6 billion compounds to identify small molecule binders of LILRB4. Biophysical validation identified APX1 as a direct LILRB4 ligand with submicromolar affinity, which was further confirmed by cellular thermal shift assay (CETSA). Docking-guided mutagenesis studies defined a discrete ligand-binding interface involving key hotspot residues required for stable target engagement. Functionally, APX1 disrupted the LILRB4-ApoE interaction in orthogonal ELISA and biolayer interferometry assays. In human iPSC-derived microglia, APX1 suppressed SHP1/2 phosphorylation, attenuated NF-κB activation and IL-1β secretion, and restored Aβ42 uptake under ApoE-driven inflammatory conditions. APX1 further demonstrated favorable in vitro developability, metabolic stability, and CNS exposure properties. In the 5xFAD mouse model of AD, oral administration of APX1 improved cognitive performance, reduced cortical and hippocampal Aβ42 burden, suppressed neuroinflammatory cytokines, and decreased activated microglial populations. Collectively, these findings establish APX1 as a promising small molecule modulator of the LILRB4-ApoE signaling axis and support pharmacological targeting of neuroimmune checkpoints as a therapeutic strategy for AD.

ID: 42427748
Title: Early Loss of Deep Restorative Sleep and Auditory Stimulus Evoked 40-Hz activity of Hippocampal Parvalbumin Neurons in the APP/PS1 Mouse Model of Alzheimer's Disease.
Abstract: Sleep abnormalities and dysfunction of gamma band (30-80 Hz) activity generated by parvalbumin (PV) interneurons are early characteristics of Alzheimer's disease (AD) which correlate with the severity of amyloid-β deposition (Aβ) and cognitive impairment. However, the timing of these alterations in vivo with respect to disease progression is unclear. Here, in longitudinal recordings from APP/PS1/PV-cre (AD mice) from 3-6 months, we found reduced sleep slow-wave power (0.5-4 Hz) in hippocampus and medial prefrontal cortex in AD mice as young as 3 months old, compared to non-AD (PV-cre) mice, well before overt pathology. This finding was primarily due to reductions in the NREM delta range (1.5-4 Hz), a hallmark of restorative functions of sleep. In contrast, beta (15-30 Hz) power linked to insomnia was significantly higher across all sleep-wake states. Loss of deep NREM sleep was not compensated by an increase in NREM sleep time, instead NREM sleep during the dark (active) phase was slightly but significantly lower in AD mice. 40-Hz auditory steady-state responses and associated evoked calcium responses of hippocampal PV neurons recorded using fiber photometry were also impaired by 3 months old. However, Y-maze performance in 3- and 6-month-old AD mice was not significantly different from non-AD mice. These results reveal reduced deep sleep and PV-associated 40-Hz activity as very early changes amenable to early intervention occurring prior to cognitive deficits. Furthermore, they establish APP/PS1 mice as a good model to causally test the relationship between sleep, PV neuronal activity and amyloid-mediated pathology.

ID: 42430835
Title: Glymphatic dysfunction in neurodegeneration: From impaired clearance to mechanism-driven therapeutic innovation.
Abstract: Glymphatic system refers to a system that involves perivascular clearance mechanisms within the brain, which are crucial for the elimination of neurotoxic proteins such as amyloid-β (Aβ) and tau proteins in Alzheimer's disease (AD), α-synuclein in Parkinson's disease (PD), and mutant huntingtin (mHTT) in Huntington's disease (HD). There is mounting evidence suggesting that glymphatic dysfunction is an important cause of neurodegenerative diseases, characterized by failure of cerebrospinal fluid-interstitial fluid (CSF-ISF) exchange due to abnormal clearance. Mechanistically, this dysfunction is affected by aging, astroglial aquaporin-4 (AQP4) depolarization, vascular impairment, sleep abnormalities, oxidative damage, and neuroinflammation. Additionally, aberrant glymphatic flow acts as a crucial link between peripheral and central pathologies, amplifying neurodegeneration via altered solute transport and inflammation signaling. Glymphatic dysfunction has been found to be involved in diseases such as AD, PD and HD, thus indicating the widespread significance of glymphatic pathology. Therapeutically, targeting glymphatic function through modulation of AQP4 polarization, improving sleep-dependent clearance, and decreasing oxidative and inflammatory mechanisms may provide promising strategy for disease modification. This review provides a comparative and mechanistic overview of glymphatic dysfunction across AD, PD, and HD, highlighting peripheral-central interactions, biomarkers, imaging approaches, and therapeutic strategies, while addressing unresolved issues related to transport mechanisms, causality versus epiphenomenon, and translational limitations.

ID: 42431913
Title: Novel approach to early prediction of alzheimer's disease progression using integrated deep regulatory genetic neural network and optimized deep belief networks.
Abstract: To enhance the prediction progression of Alzheimer's Disease is very excavating process. It is often very difficult to implement in the chronic neurodegenerative disease-related preprocessed gene expression data. Especially, Alzheimer's Disease (AD) prediction is a very crucial process in AD metadata diagnosis. Novelty: To explore this challenging prediction process in brain disease prediction, this research presents a proposed deep learning model, namely the Integrated Deep Regulatory Genetic Neural Network and Optimised Deep Belief Networks (IDRODN). This integration increases the affluence of prediction progression from genomic data. These prediction systems help identify early AD. This research utilizes the IDRODN, which can predict and confine each network's neurons and hidden layers against the benchmark dataset of Alzheimer's gene expression and uncertainty to predict Alzheimer's Disease. The comparative analysis on data from the Alzheimer's disease gene expression data Initiative database has achieved an accuracy of 98.3%. In addition, it has achieved a high F1 score of 0.986 for predicting different stages from Gene expression data. This shows the most accurate technique for predicting Alzheimer's Disease (AD) using the prognostic IDRODN model.

ID: 42431966
Title: An interpretable multimodal framework using compact biomarkers and Kolmogorov-Arnold networks improves the early diagnosis of Alzheimer's disease.
Abstract: Early diagnosis of Alzheimer's disease (AD), especially accurate identification at the mild cognitive impairment (MCI) stage, is crucial for slowing disease progression. Although deep learning has achieved promising performance in AD diagnosis, existing multimodal models often operate as "black boxes," lacking the transparency required for clinical practice and failing to explicitly model deep interactions between imaging and clinical features. To address these limitations, this study proposes an interpretable multimodal framework, namely the Compact Biomarker Kolmogorov-Arnold Network (CBKAN). Specifically, we introduce EHCTNet with disease-specific attention to extract features from 3D MRI data, and innovatively constrain the encoder to output a set of compact biomarkers instead of traditional high-dimensional abstract vectors, mimicking the diagnostic logic of clinicians (e.g., judging brain atrophy). In addition, a hybrid feature Transformer is used to fuse these imaging biomarkers with clinical and genetic data, explicitly capturing complementary relationships across modalities. Finally, the Kolmogorov-Arnold Network (KAN) is adopted as the classifier to effectively model the highly nonlinear characteristics of AD progression. Experiments on 800 subjects from the ADNI dataset show that CBKAN achieves 91.1% accuracy and an F1-score of 0.910 in the AD/MCI/CN classification task, significantly outperforming existing mainstream methods. Statistical analyses validate the effectiveness of each component of the model. The proposed model provides a potentially interpretable and high-performing decision-support framework for early Alzheimer's disease diagnosis, although its cross-cohort generalizability and real-world clinical utility require further validation in independent external datasets.

ID: 42432263
Title: Repurposing apremilast for alzheimer's disease: multitarget modulation of cAMP‑PI3K/Akt-GSK‑3β and NF‑κB signaling.
Abstract: Alzheimer's disease (AD), the leading cause of dementia worldwide, represents a growing global health challenge driven by population aging, the absence of effective disease-modifying therapies, and its inherently multifactorial pathogenesis. This pathogenesis is characterized by amyloid-β (Aβ) aggregation, tau hyperphosphorylation, persistent neuroinflammation, oxidative stress, and synaptic dysfunction. Conventional single-target interventions have consistently failed against this complex interplay of molecular events, thereby highlighting the need for multitarget, systems pharmacology approaches capable of simultaneously modulating convergent pathways. Apremilast (APR), an FDA-approved, orally bioavailable phosphodiesterase-4 (PDE4) inhibitor, has recently emerged as a favorable drug repurposing candidate capable of elevating intracellular cAMP and triggering a cascade of neuroprotective mechanisms. Preclinical investigations from Aβ-challenged neuronal cultures to high-fat diet/streptozotocin-induced rodent models of AD demonstrate that APR attenuates Aβ-induced cytotoxicity, improves cognitive performance, and preserves neuronal and synaptic integrity. Mechanistically, APR mitigates NF-κB-mediated neuroinflammation through IκBα stabilization, thereby reducing the release of proinflammatory cytokines such as TNF-α and IL-6; activates the Nrf2/HO-1 antioxidant defense pathway, and, via cAMP-dependent PI3K/Akt signaling, inhibits GSK-3β to prevent tau hyperphosphorylation, synaptic loss, and neuronal degeneration. This review synthesizes current mechanistic evidence supporting apremilast as a potential multitarget repurposing candidate in AD, thereby addressing key knowledge gaps in the current literature. All supporting evidence was compiled from peer-reviewed sources indexed in PubMed, Web of Science, and Scopus. Guided by network pharmacology and systems biology frameworks, APR's polypharmacological profile positions it as a compelling multitarget candidate for advanced in vivo validation, human iPSC-derived neuronal studies, and AI-driven therapeutic discovery pipelines.

ID: 42435703
Title: Rationally designed phytochemical-derived carbamate hybrids unveiling potent inhibition of cholinesterase and amyloid-β peptides.
Abstract: Alzheimer's disease (AD) is most likely to be caused by the accumulation of Aβ and dysfunction of the cholinergic pathology. Oxidative damage, alterations of brain glucose metabolism, and cognitive impairment are all demonstrated in the STZ models. In order to overcome such effects, a new set of phenolic-carbamate conjugates (5a-5h) was synthesized, and their structures were elucidated using FTIR, UV, and NMR spectroscopy. The in silico studies confirmed excellent binding capabilities against AChE and Aβ targets. In vitro antioxidant assays depicted a significant free radical scavenging ability, with compound 5c exhibiting the enhanced effect. Cell line study with SH-SY5Y and PC12 cells showed greater % cell viability. AChE activity demonstrated compound 5c has significant effectiveness (IC50 = 1.98 uM). Neurobehavioral activity showed an improvement in learning and memory during behavioural assessments. In vivo antioxidant study showed greater scavenging activity (SOD, CAT, GSH), reduced of oxidative stress (MDA, NO), and the improvement in total antioxidant activity. Overall, the compound 5c has demonstrated significant results comprising decreased cholinesterase and Aβ inhibition deciphering enhanced cholinergic restoration. Hippocampal integrity was preserved, as it was confirmed by histopathological examination. It concludes that bromo-vanillyl carbamate derivative 5c (30 mg/kg) has potent antioxidant, anti-amyloid, and neuroprotective characteristics, rendering it a promising multitarget lead that warrants further investigation for the treatment of AD.

ID: 42435996
Title: Targeting the APOE4-driven peripheral-central immune axis: A new frontier for Alzheimer's disease therapy.
Abstract: Alzheimer's disease (AD) is a progressive neurodegenerative disorder and a growing global health challenge. Despite decades of research dominated by the amyloid cascade hypothesis, single-target therapies aimed at Aβ or tau have largely failed, underscoring the need for a broader framework. Emerging evidence implicates neuroimmune dysfunction as a central driver of AD pathology, with the "peripheral-central immune axis" emerging as a critical node. The APOE4 allele, the strongest genetic risk factor for sporadic AD, plays a pivotal role in both central nervous system (CNS) lipid metabolism and peripheral immune homeostasis. This review synthesizes the association between APOE4 and peripheral immune dysregulation and its impact on neurodegeneration. We discuss APOE expression in CNS and peripheral immune cells, highlighting APOE4-associated alterations in monocyte/macrophage polarization, T cell subsets via IL-7/IL-7R downregulation, and gut microbiota composition. We delineate mechanisms by which APOE4 is associated with blood-brain barrier compromise, may promote conditions for immune cell trafficking, and contributes to neuroinflammation. Integrating preclinical and clinical evidence, we propose an "APOE4-associated peripheral-central immune infiltration cascade" as a unifying framework for understanding systemic AD pathogenesis. Finally, we review emerging therapeutic strategies targeting peripheral immunity and APOE, discussing multi-target approaches guided by APOE genotype and immune biomarkers, shifting from a CNS-centric toward a systemic immunomodulatory paradigm for precision medicine.

ID: 42438861
Title: Antidepressant use and dementia, cognitive measures, and neuroimaging outcomes: A population-based cohort study.
Abstract: Prior observational studies have reported conflicting results regarding whether antidepressant treatment reduces long-term dementia risk, likely due to confounding by indication and reverse causation. We aimed to investigate the association between baseline antidepressant use and incident dementia, incorporating cognitive and neuroimaging outcomes. We conducted a prospective cohort study using UK Biobank participants free of dementia at baseline. Antidepressant use was self-reported at baseline (2006-2010). Incident dementia was identified through linked electronic health records until December 19, 2022. Cox proportional hazards models estimated hazard ratios (HRs) for all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VD), adjusting for sociodemographic, lifestyle, health-related, antidepressant indication factors, and co-medication of other anticholinergics. In subsamples, cognitive performance (n = 57,330) and structural brain imaging (n = 42,276) were examined as intermediate outcomes. Among 461,464 participants, 33,721 (7.3%) reported baseline antidepressant use. Over a mean follow-up of 13.4 years, 7,922 (1.7%) developed incident dementia. Baseline antidepressant use was associated with higher risks of all-cause dementia (adjusted HR: 1.47, 95% CI 1.36-1.60), AD (1.53, 1.36-1.73), and VD (1.44, 1.23-1.70). Users performed worse on fluid intelligence and prospective memory tasks and showed lower total and gray matter volume, regional reductions in the hippocampal gray matter and basal nucleus, and greater white matter hyperintensity volume. Baseline antidepressant use was linked to a higher risk of dementia, poorer cognitive performance, and adverse brain structural changes. These findings underscore the importance of judicious prescribing, regular cognitive monitoring, and consideration of non-pharmacological approaches in clinical care.

ID: 42439681
Title: Rethinking Anti-Inflammatory Therapy in Alzheimer's Disease: From Broad Suppression to Stage-State-Space Neuroimmune Reprogramming.
Abstract: Alzheimer's Disease (AD) is now understood as a biologically diverse condition, with amyloid and tau pathology evolving within dynamic neuroimmune networks. This challenges the traditional view that AD-related inflammation can be broadly suppressed therapeutically. We review evidence showing that neuroinflammation in AD is stage-dependent, cell-state-specific, spatially organized, and functionally complex. Microglia and astrocytes can aid in plaque containment, debris clearance, synaptic balance, metabolic adaptation, and tissue repair, but may also exacerbate injury through type-I interferon, inflammasome, complement, tumor necrosis factor, and lipid pathways. Many failed anti-inflammatory trials likely stem from mismatches in targets, timing, spatial considerations, pathway redundancy, and biomarker selection, rather than invalidating neuroinflammation as a therapeutic target. Recent single-cell and spatial transcriptomic, proteomic, metabolomic, and network-medicine studies offer a framework for precision intervention by identifying inflammatory endotypes, anatomical niches, and pathway modules. We propose the Stage-State-Space Neuroimmune Reprogramming Model (S3-NRM), aligning AD immunotherapy with disease stage, glial/endotype state, and spatial inflammatory niche, guided by fluid, imaging, and omics biomarkers. Future therapies should selectively suppress harmful immune responses while preserving beneficial glial functions.

ID: 42440686
Title: Comparison of safety of lecanemab and donanemab: a real-world disproportionality analysis using the FDA adverse event reporting system.
Abstract: Lecanemab and donanemab are anti-amyloid-β (Aβ) monoclonal antibodies recently approved for the treatment of Alzheimer's disease (AD). Although both agents have demonstrated therapeutic potential, their post-marketing adverse event reporting profiles remain insufficiently characterized and compared in spontaneous reporting systems. This study aimed to systematically compare adverse event signals associated with these two drugs using the FDA Adverse Event Reporting System database, with sex-stratified and sensitivity analyses performed to support the main findings. FAERS reports up to the fourth quarter of 2025 were retrospectively analyzed. Reports in which lecanemab or donanemab was recorded as the primary suspect drug were included. AEs were classified by system organ classes (SOCs) and preferred terms (PTs) according to the Medical Dictionary for Regulatory Activities (MedDRA). Signal detection was performed using four algorithms: reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker (MGPS). Sex-stratified analysis, sensitivity analysis after excluding reports involving concomitant medications, and time-to-onset (TTO) analysis based on the Weibull shape parameter model were also conducted. False discovery rate (FDR) correction was applied to analyses involving multiple P values. A total of 3,640 AE reports were identified, including 2,602 for lecanemab and 1,038 for donanemab. Nervous system disorders was the most frequently reported SOC and the only SOC meeting the positivity criteria across all four algorithms for both drugs. At the PT level, the frequently reported events for both drugs were mainly concentrated in amyloid-related imaging abnormality (ARIA)-related events, including ARIA with oedema/effusion (ARIA-E) and ARIA with microhaemorrhages/haemosiderin deposition (ARIA-H), headache, and infusion-related reactions. The strongest disproportionality reporting signals were mainly observed for ARIA-related preferred terms and cerebral microhaemorrhage. In separate FAERS-based disproportionality analyses, lecanemab showed stronger disproportionality reporting signals for ARIA-H, whereas donanemab showed stronger disproportionality reporting signals for ARIA-E. In addition, drug-specific PT signal distributions differed between the two agents. Several potential novel PT signals were also identified. Sex-stratified analysis suggested differences in the distribution of certain PT signals between female and male reports. Sensitivity analysis supported the stability of most core signals. The median TTO was 46 days for lecanemab and 31 days for donanemab, and Weibull analysis suggested different temporal patterns of AE occurrence. Using four signal detection algorithms, this study compared real-world adverse event reporting profiles associated with lecanemab and donanemab. The two drugs showed both shared and distinct adverse event reporting profiles, particularly in ARIA subtype-related disproportionality signals, drug-specific PT signals, potential novel reporting signals, sex-stratified reporting patterns, and TTO characteristics. These findings provide pharmacovigilance evidence for targeted safety monitoring and hypothesis generation, but should not be interpreted as causal associations or true incidence estimates.

ID: 42443967
Title: Microglial mitophagy as an immunometabolic checkpoint in alzheimer's disease: linking mitochondrial quality control to neuroinflammation.
Abstract: AD is a complex neurodegenerative disorder characterized by chronic neuroinflammation. Microglia, the brain's resident immune cells, centrally regulate AD pathophysiology. Recent studies have highlighted microglial mitophagy as an important interface linking mitochondrial quality control to innate immune responses.Intact mitophagy facilitates the timely clearance of damaged mitochondria, thereby limiting the release of mitochondrial DAMPs (e.g., mtDNA and mtROS) and helping restrain aberrant activation of the cGAS-STING pathway and the NLRP3 inflammasome.In the AD pathological milieu, however, factors including Aβ deposition, tau pathology, and genetic risk variants such as TREM2 and APOE4 disrupt mitophagy at multiple levels-from initiation and recognition to lysosomal degradation. This review systematically summarizes the molecular regulatory network of microglial mitophagy, with a particular focus on the mechanisms by which AD-associated pathological factors impair this process. We further discuss potential mechanisms through which mitophagic dysfunction may contribute to the amplification of neuroinflammation, including the release of mitochondrial DAMPs, the reprogramming of TBK1 signaling, and intercellular interactions. Finally, we outline current therapeutic strategies aimed at restoring mitophagy and discuss their potential to modulate neuroinflammatory responses and AD-related pathological processes, while highlighting the challenges and future directions in this emerging field.

ID: 42444752
Title: Anti-amyloid nanobody-Fc fusion protein drives potent amyloid clearance through microglial recruitment.
Abstract: Anti-amyloid beta (Aβ) monoclonal antibodies are effective at lowering amyloid in Alzheimer's disease (AD). However, whether Fc-mediated effector function is absolutely required for efficacy is not completely understood. This is important for optimizing therapeutic efficacy and mitigating side effects such as amyloid-related imaging abnormalities (ARIA). Antibodies lacking Fc effector function, like single-domain antibodies (nanobodies), offer a unique tool to dissect these mechanisms, as their small size facilitates blood-brain barrier (BBB) penetration and allows Fc-mediated functions to be studied independently. We immunized a llama with Aβ aggregates and constructed a phage display library to screen for aggregate-specific nanobodies. Lead candidates were characterized by epitope mapping and binding affinity to amyloid plaques in both murine and human AD brain tissues. We further assessed their BBB permeability and evaluated their efficacy in clearing pre-existing plaques in amyloid precursor protein (APP)/presenilin 1 (PS1) mice. We identified two lead nanobodies, 3A11 and 2D10, that bind distinct epitopes and specifically bind Aβ plaques in murine and human AD brain tissues. Following systemic administration, the monovalent, unmodified (Fc-less) 2D10 nanobody, but not 3A11, successfully crossed the BBB and engaged amyloid plaques in APP/PS1 mice. However, despite robust target engagement, the Fc-less 2D10 failed to recruit microglia or reduce plaque burden. In contrast, an engineered 2D10-Fc fusion antibody potently cleared amyloid plaques, achieving a reduction in pathology comparable to aducanumab treatment. This efficacy was directly correlated with Fc-mediated microglial recruitment and activation, demonstrating that the Fc domain is essential for phagocytic plaque removal. Our findings demonstrate that Fc effector function is indispensable for microglial-mediated amyloid clearance in vivo. By clarifying this fundamental mechanism, this study provides a framework for the rational design of next-generation immunotherapies. Furthermore, 2D10-Fc represents a promising therapeutic candidate, combining the high-affinity targeting of nanobodies with the effector power necessary for robust plaque clearance.

ID: 42444987
Title: The amino acid substitutions A30W, K28A, and M35C alter amyloid-β peptide toxicity in cell culture and in an in vivo model of amyloidosis in Caenorhabditis elegans.
Abstract: The buildup of toxic aggregates formed by the amyloid-β peptide 1-42 (Aβ42) is a central process in Alzheimer's disease (AD) pathology. The peptide's self-assembly and toxicity are highly dependent on its primary amino acid sequence and can be altered by modifying key residues. Specifically, the single amino acid substitutions A30W, K28A, and M35C can reduce the aggregation and toxicity of the Aβ42 peptide. In this study, we further evaluated the effects of these mutations in a C6 rat glioma cell line and in the Caenorhabditis elegans strains CL2006 and CL4176, which express muscular Aβ42 as an in vivo model. Our results showed that the A30W, K28A, and M35C substitutions reduce apoptosis induction in cell culture, in contrast to the WT Aβ42 peptide. In C. elegans, the three variants extended the lifespan of CL2006 worms by reducing fibrillar aggregates or altering aging, whereas the M35C peptide delayed the paralysis of CL4176 worms. Additionally, the substitutions altered oxidative stress and autophagy in control worms. Taken together, these results suggest that the A30W, K28A, and M35C substitutions reduce Aβ42 toxicity in cell culture and in C. elegans and could protect the nematode against Aβ42 toxicity.

ID: 42445022
Title: High-Throughput CETSA Identifies Small Molecule Modulators of ILT3 (LILRB4) with Functional Activity in Human iPSC-Derived Microglia for Alzheimer's Disease.
Abstract: Immune inhibitory signaling in microglia contributes to impaired amyloid-β (Aβ) clearance and neuroinflammation in Alzheimer's disease (AD), yet small molecule modulators targeting these pathways remain largely unexplored. Here, we report the development of a high-throughput cellular thermal shift assay (HT-CETSA) platform for identification of small molecule binders targeting the inhibitory immune receptor ILT3 (LILRB4). Screening of ∼40 000 compounds yielded multiple validated hits, including IB15C, a submicromolar ILT3 binder identified through preliminary structure-activity relationship optimization. Orthogonal validation by microscale thermophoresis, surface plasmon resonance, docking, and site-directed mutagenesis confirmed direct and target-specific ILT3 engagement. Functionally, IB15C disrupted the ILT3-ApoE interaction and restored microglial activity in human iPSC-derived microglia, reducing SHP1/2 and NF-κB signaling, suppressing IL-1β secretion, and enhancing Aβ uptake. IB15C also demonstrated favorable in vitro pharmacokinetic and safety properties, supporting further development of ILT3-targeted neuroimmune therapeutics.

ID: 42446869
Title: Single-cell analysis of Powassan virus-infected brains reveals age-dependent neuroinflammatory crosstalk and progressive Alzheimer's-like APP/Aβ accumulation.
Abstract: Powassan virus (POWV) causes lethal encephalitis in the elderly and long-term neurological sequelae in survivors. Mirroring human disease, POWV strain LI9 directs age-dependent lethality in C57BL/6 (B6) mice, resulting in spongiform encephalitis, gliosis, and inflammatory cytokine/chemokine responses in the CNS. However, the mechanisms underlying age-dependent lethality and persistent neurodegenerative disease in POWV survivors remain to be resolved. Here, we analyzed cellular CNS responses to POWV LI9 infection in young (10-week-old) and aged (50-week-old) mice using single-cell RNA sequencing. Infection of young mice resulted in inflammatory CNS infiltrates (NK, CD4/CD8 T cells, and monocytes) and interferon responses that coincide with peak viral burden. In contrast, the CNS of aged infected mice instead featured upregulated astrocyte and neuronal genes associated with neurodegenerative and Alzheimer's disease pathways and the transition of homeostatic microglia to a Trem2-ApoE-linked disease-associated microglial transcriptional state. Histological analysis revealed that amyloid precursor protein (APP)/amyloid-β (Aβ) accumulated in the CNS following POWV infection and that POWV envelope protein and APP/Aβ were selectively localized within layers L5/L6 of the cerebral cortex. POWV kinetically increased perinuclear APP/Aβ accumulation during acute infection and was highly expressed in the CNS of POWV survivors. Our findings reveal that POWV triggers glial cell responses and a neurodegenerative disease-associated microglia program of Alzheimer's-like APP/Aβ accumulation in mice, which is consistent with long-term neurological sequelae in human POWV survivors.IMPORTANCEPowassan virus (POWV) causes lethal encephalitis and long-term cognitive deficits in survivors. Using an age-dependent murine model, we reveal that POWV-infected young mice direct robust CNS inflammatory infiltrates associated with viral clearance, whereas aged mice exhibit impaired immune responses and a shift from homeostatic to neurodegenerative glial cell states. POWV prompted the induction of disease-associated microglia (DAM) and Trem2-ApoE axis transcriptional responses that are hallmarks of APP/amyloid-β (Aβ) accumulation in Alzheimer's disease (AD). Remarkably, POWV induced progressive APP/Aβ accumulation in young and aged mice that persisted in survivors after viral clearance. This suggests that POWV induces an APP/Aβ neurodegenerative process and provides a potential cause of long-term neurological sequelae observed in human POWV survivors. Our data suggest that POWV initiates or exacerbates AD-like neuropathology and further rationalizes investigating the role of APP/Aβ responses in other encephalitic viruses.

ID: 42446992
Title: Repurposing trazodone for Alzheimer's disease to modulate soluble ST2 levels and alleviate Alzheimer's pathology.
Abstract: Alzheimer's disease (AD) is a multifactorial disorder involving various pathological mechanisms, such as amyloidosis, immune dysfunctions, and synaptic impairments, which are important therapeutic targets. Repurposing drugs to target these mechanisms offers a promising approach to reduce the costs and duration of drug development. Genetic studies underscore the critical role of microglial clearance of amyloid-beta (Aβ) in AD pathogenesis. Specifically, soluble ST2 (sST2)-one of the two major isoforms of the ST2 protein encoded by the IL1RL1 (interleukin-1 receptor-like 1) gene-acts as a decoy receptor isoform that interferes with IL-33/ST2 signaling and has been identified as a disease-modifying factor that impairs microglial Aβ clearance functions. In this study, we investigated drug repurposing opportunities to modulate sST2 levels and alleviate AD pathologies. Unbiased screening of commonly used medications in AD patients, followed by validation in model systems, identified trazodone-an antidepressant used to treat major depressive disorder-as a leading negative regulator of sST2. Trazodone primarily suppresses sST2 expression through its antagonistic effects on adrenergic signaling. In the APP/PS1 transgenic mouse model of AD, trazodone treatment enhanced microglial interaction with Aβ and alleviated Aβ pathology. Furthermore, trazodone reduced neurodegeneration and rescued synaptic deficits in APP/PS1 mice. Comprehensive molecular profiling of APP/PS1 mouse brains showed that trazodone restored the expression of synaptic proteins critical for synaptic integrity and plasticity. Overall, these findings demonstrate that trazodone is a promising repurposing candidate for AD that targets underlying immune dysfunctions and synaptic impairment.