Liver-metabolic stress and apolipoprotein E (APOE) ε4 are implicated in late-life cognitive vulnerability, yet how hepatic-metabolic indices relate to cognition and amyloid burden and whether these as Show more
Liver-metabolic stress and apolipoprotein E (APOE) ε4 are implicated in late-life cognitive vulnerability, yet how hepatic-metabolic indices relate to cognition and amyloid burden and whether these associations vary by APOE ε4 allele dose remains unclear. We examined liver-metabolic indices in relation to cognition and amyloid PET SUVR and tested effect modification by APOE ε4. We analyzed baseline data from the Dementia Platform Korea Trial-Ready Registry (DPK-TRR). Primary multivariable analyses used complete cases for outcomes and covariates ( Higher TyG index and AST/ALT ratio were associated with lower MMSE scores (TyG: Routine liver-metabolic indices were associated with cognitive performance, while FIB-4 stage showed effect modification by APOE ε4 in relation to both cognition and amyloid PET SUVR. These findings support heterogeneity in liver-metabolic and genetic contributions to late-life cognitive vulnerability in a dementia trial-ready registry and motivate longitudinal studies to clarify temporal relationships. Show less
Alzheimer's disease (AD) is an irreversible neurodegenerative disease defined by its molecular hallmarks - amyloid beta peptide plaques and neurofibrillary Tau tangles. Despite significant progress th Show more
Alzheimer's disease (AD) is an irreversible neurodegenerative disease defined by its molecular hallmarks - amyloid beta peptide plaques and neurofibrillary Tau tangles. Despite significant progress that has been made in uncovering a large number of genetic risk factors through extensive genomic sequencing and genetic studies, the molecular mechanisms driving AD-associated pathology and cognitive decline remain poorly understood. Therefore, alongside the identification of more risk genes, it is also paramount to study how these genes function and influence each other within the cellular pathways and overall molecular networks in AD-relevant brain cell types. However, current human protein-protein interactome datasets were all generated in either yeast or generic human cell lines. Consequently, many important neuronal interactions, especially neuron-specific ones, have yet been discovered. To address this critical gap, we developed a highly scalable, high-quality interactome mapping pipeline in human excitatory neurons derived from induced pluripotent stem cells (iPSC), and generated a comprehensive, neuron-specific interactome map, named ADNeuronNet, for key AD risk genes. ADNeuronNet consists of 1,767 high-confidence interactions among 1,189 proteins and is the only dataset enriched with neuron-specific genes when compared to known protein interactions, including previous large-scale interactome maps, for the same baits in the literature. Within ADNeuronNet, we identified 1,375 novel interactions, many of which are likely neuron specific. For example, we identified a neuron-specific interactor, RIN2, for major AD risk factor BIN1 and confirmed RIN2's function in recruiting BIN1 to RAB5 positive early endosomes, a process that has been well-associated with AD etiology. Additionally, we performed quantitative interaction perturbation analyses on AD risk genes with AD-associated mutations or isoforms and identified significant changes in 99 protein interactions among 11 different protein variants. Finally, we found that subunits from the anaphase-promoting complex/cyclosome (APC/C), another novel BIN1 interactors identified by ADNeuronNet, mediated modulation of Tau-aggregation in neurons via regulation of APOE expression, uncovering a previously unrecognized BIN1-APC/C-APOE regulatory axis in AD pathobiology. In summary, these findings illustrate how our neuron-specific ADNeuronNet can be leveraged to uncover new risk gene candidates and cellular pathways that help advance our understanding of molecular mechanisms underlying AD etiology. Show less
This study aimed to compare positron emission tomography (PET) and plasma-based temporal modeling of amyloid and tau biomarkers in Alzheimer's disease. Longitudinal amyloid PET (n = 1,097, mean age ± Show more
This study aimed to compare positron emission tomography (PET) and plasma-based temporal modeling of amyloid and tau biomarkers in Alzheimer's disease. Longitudinal amyloid PET (n = 1,097, mean age ± SD = 72.5 ± 7.38 year, 51.4% male), Plasma and PET models generated similar results for estimated amyloid and tau onset, with stronger model agreement for tau (r = 0.88[0.86, 0.89], t = 57.4, p < 0.001) than amyloid (r = 0.75[0.72, 0.77], t = 37.4, p < 0.001) onset. Accuracy of estimated onset compared to actual onset was high within modality (mean absolute error [MAE] ≤ 2.03) with slightly greater error (MAE 3.09-3.42) when comparing across modalities (ie, plasma to PET). For both plasma and PET, earlier tau onset was associated with younger amyloid onset, female sex, and ≥1 apolipoprotein (ApoE) ε4 allele. Earlier dementia onset after tau was associated with later tau onset for both plasma and PET, while male sex was associated with shorter tau to dementia gap in plasma models. Temporal modeling of plasma biomarkers provides comparable information to PET-based models, particularly for tau onset age, and can serve as a widely accessible tool for clinical assessment of biological disease severity. ANN NEUROL 2026. Show less
Non-alcoholic fatty liver disease and atherosclerosis may share a common pathogenesis involving chronic IL-1β-induced inflammation. We aimed to evaluate the efficacy of diacerein, an IL-1 pathway inhi Show more
Non-alcoholic fatty liver disease and atherosclerosis may share a common pathogenesis involving chronic IL-1β-induced inflammation. We aimed to evaluate the efficacy of diacerein, an IL-1 pathway inhibitor, in improving liver fibrosis, steatosis, and atherosclerosis in apolipoprotein E-knockout (apoE k/o) mice. ApoE k/o mice fed a high-fat diet (HFD) were divided into three groups based on diacerein dosage. Liver fat accumulation and fibrosis severity were compared across groups, along with changes in the expression of genes related to lipid metabolism and fibrosis. Atherosclerotic burden in the aorta was evaluated via en face analysis, and the related signaling pathway was verified in vitro. Diacerein treatment reduced the amount of collagen fibers and fat accumulation in the liver in a dose-dependent manner as well as fibrosis-related gene expression. Atherosclerotic plaque burden in the aorta showed a decreasing trend with diacerein treatment, accompanied by reduced expression of pro-inflammatory cytokines, including TNF-α. Diacerein treatment ameliorated liver steatosis/fibrosis and showed beneficial effects on atherosclerosis-related mechanisms in HFD-fed apoE k/o mice. Given its dual anti-inflammatory and anti-fibrotic actions, diacerein represents a promising therapeutic candidate for metabolic disorders characterized by chronic inflammation. KEY MESSAGES: We analyzed the effects of diacerein on liver fibrosis, steatosis, and atherosclerosis in apolipoprotein E knockout (apoE k/o) mice. Diacerein reduced fat accumulation in the liver and collagen fibers in the liver. It decreased the expression of genes related to fibrosis and the burden of atherosclerotic plaque in the aorta. The expression of pro-inflammatory cytokines was reduced. Treatment of apoE knockout mice fed an HFD with diacerein effectively ameliorated liver steatosis/fibrosis and atherosclerosis. Show less
Clarifying relationships between amyloid, tau, and cognition is crucial to understanding dementia risk, but has been mainly performed in non-Hispanic White (NHW) participants. It is unknown whether fi Show more
Clarifying relationships between amyloid, tau, and cognition is crucial to understanding dementia risk, but has been mainly performed in non-Hispanic White (NHW) participants. It is unknown whether findings are generalizable to other ethnoracial groups. We evaluated relationships between amyloid-β (Aβ) positivity, apolipoprotein E allele (APOE) ε4, tau-positron emission tomography (PET) Black (β = 0.28, p < 0.001) and Hispanic (β = 0.34, p < 0.001) participants had higher medial temporal lobe (MTL) tau than NHW participants; however, findings were attenuated when accounting for choroid plexus off-target binding. Hispanic participants showed higher tau in lateral temporal regions compared to NHW and Black participants; however, reducing meningeal off-target binding through erosion demonstrated similar lateral temporal tau across groups. Factors other than amyloid and tau may impact cognition in Black participants. PI2620 off-target ethnoracial differences should be investigated. Show less
BackgroundMetformin has been proposed to have neuroprotective benefits, but its effects on AD-related brain changes remain unclear and may be influenced by apolipoprotein E ε4 (
The proteasome is a major intracellular protease complex, but the significance of circulating proteasome activity in Alzheimer’s disease (AD) is not well established. Because APOE ε4 is the strongest Show more
The proteasome is a major intracellular protease complex, but the significance of circulating proteasome activity in Alzheimer’s disease (AD) is not well established. Because APOE ε4 is the strongest genetic risk factor for AD, we examined whether plasma proteasome activity is associated with AD-related pathology, neurodegeneration, and cognitive decline, focusing on APOE ε4 carriers. In this observational study, participants were classified as cognitively normal (CN), mild cognitive impairment (MCI), and dementia. All underwent 3.0-T MRI, [ A total of 148 individuals were included (58 CN, 39 MCI, 38 AD dementia, and 13 other dementia). Significant associations appeared only in APOE ε4 carriers ( Downregulated proteasome activity is strongly associated with amyloid burden, early tau accumulation, hippocampal atrophy, and cognitive impairment only in APOE ε4 carriers. These findings suggest that plasma proteasome activity may serve as a noninvasive marker of AD-related vulnerability in genetically at-risk individuals. Further studies are needed to clarify whether proteasome activity contributes to or results from amyloid and tau aggregation. KCT0005428. Registered September 24, 2020. Study subjects included in this analysis were those recruited from November 2018 onwards (retrospectively registered). The online version contains supplementary material available at 10.1186/s13195-026-01994-w. Show less
Cardiovascular disease (CVD) risk is elevated among people living with HIV (PLWH), particularly those receiving antiretroviral therapy (ART). This study aimed to examine associations between single-nu Show more
Cardiovascular disease (CVD) risk is elevated among people living with HIV (PLWH), particularly those receiving antiretroviral therapy (ART). This study aimed to examine associations between single-nucleotide polymorphisms (SNPs) in lipoprotein-related genes and CVD risk among PLWH undergoing ART. Blood samples from 337 PLWH at Chung Shan Medical University Hospital were analyzed, including 238 individuals who switched ART and 99 who continued their regimen. Genotyping of four SNPs-namely, ATP binding cassette B1 ( The cohort was predominantly male 95.6% (322/337), with a mean age of 34.6 years. Metabolic abnormalities were common, and 16.0% (54/337) of participants on ART were classified as high-risk for CVD. Among the SNPs analyzed, SNPs in Show less
The APOE-ε4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease. However, APOE-ε4 is not deterministic, highlighting the need to identify additional genetic and environmenta Show more
The APOE-ε4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease. However, APOE-ε4 is not deterministic, highlighting the need to identify additional genetic and environmental factors. APOE-ε4 has been linked to accelerated cognitive decline, so we sought to investigate genetic factors that modify APOE-ε4-associated cognitive decline. We conduct cross-ancestry APOE-ε4-stratified and interaction GWAS using harmonized cognitive data from 32,778 participants, including 29,354 non-Hispanic White and 3,424 non-Hispanic Black individuals. Our primary outcome is late-life cognition, measured using harmonized composite scores for memory, executive function, and language, modeled as continuous traits reflecting both normative cognitive aging and disease-related decline. We identify two genome-wide significant loci in APOE-ε4 carriers, reaching genome-wide significance for executive function. These loci also demonstrate nominal associations across the other domains, suggesting broad effects on cognition. In non-carriers, we identify a genome-wide significant association at ITGB8 restricted to executive function, and another locus associated with language. We further link these loci to SEMA6D, GRIN3A, and ITGB8 through expression and methylation databases. Post-GWAS analyses implicate additional genes including SLCO1A2, and DNAH11. Genetic correlation analyses reveal differences by APOE-ε4 status for immune-related traits, suggesting immune-related predispositions may exacerbate cognitive risk in APOE-ε4 carriers. Show less
Growing evidence supports that epigenetic dysregulation through histone deacetylases (HDACs) plays a critical role in synaptic dysfunction and memory loss in Alzheimer’s disease (AD), and that HDACs h Show more
Growing evidence supports that epigenetic dysregulation through histone deacetylases (HDACs) plays a critical role in synaptic dysfunction and memory loss in Alzheimer’s disease (AD), and that HDACs have been highlighted as an attractive class of targets for AD therapy. Moreover, restoring Wnt/β-catenin signaling, which is greatly suppressed in AD brains, is a promising therapeutic strategy. CI-994 is an orally active class I HDAC inhibitor that has undergone several phase II/III clinical trials on cancer treatment. Importantly, CI-994 can cross the blood–brain barrier and is a cognitive enhancer. Wnt activity was initially examined by Wnt reporter activity assay in Wnt3A-expression HEK293 cells, and profiling HDAC inhibition was performed against 10 individual HDACs. Activities of CI-994 on class I HDACs and Wnt/β-catenin signaling were further tested in HEK293 cells, LRP6-expressing HT1080 cells and neuronal SH-SY5Y cells. The therapeutic effects of CI-994 were examined in patient-specific iPSC-derived neurons and cerebral organoids carrying We herein report that CI-994 is not only a potent class I HDAC inhibitor but also an activator of Wnt/β-catenin signaling. Mechanistically, activation of Wnt/β-catenin signaling by CI-994 is associated with stabilizing Wnt co-receptor LRP6 protein and modulating HDAC activity. Importantly, CI-994 significantly increases histone acetylation, activates Wnt/β-catenin signaling, and decreases tau phosphorylation in patient-specific iPSC-derived cerebral organoids carrying Our findings suggest that CI-994 can be repurposed as a novel therapeutic agent for AD therapy. The online version contains supplementary material available at 10.1186/s13195-026-01982-0. Show less
Understanding the genetic foundations of dementia is critical to unraveling its complex molecular basis. Given that a clinical diagnosis of Alzheimer's disease (AD) dementia often results from interpl Show more
Understanding the genetic foundations of dementia is critical to unraveling its complex molecular basis. Given that a clinical diagnosis of Alzheimer's disease (AD) dementia often results from interplay between multiple underlying neuropathologic co-morbidities, previous genome-wide association studies (GWAS) of clinically diagnosed AD are restricted in their ability to translate genetic associations to potential targeted therapeutics. The current study seeks to address these limitations by presenting the largest GWAS to date (n=12,509) of neuropathologic hallmarks of AD and AD related dementias (ADRDs). We further performed a candidate-variant analysis using loci previously identified in GWAS of clinically diagnosed AD dementia and Parkinson's disease (PD). Finally, we conducted heritability and genetic correlation analyses using linkage disequilibrium (LD) score regression. We found broad genome-wide significant associations with Clinically diagnosed Alzheimer's disease (AD) dementia is commonly associated with its hallmark pathologic changes plus neuropathologic features of prevalent co-morbid diseases such as cerebrovascular disease, Lewy body disease, and more recently discovered abnormalities in protein called TDP-43 (collectively, AD related dementias; ADRD). As a result, previous studies that associated clinical diagnosis of AD with specific genes may not tell us the whole story. For this study, we gathered autopsy and genetic data to identify relationships between genes and dementia-associated brain changes. We found some relationships between these diseases and genes that had been previously identified as contributing to clinical dementia, as well as some new relationships that had been previously unknown. We also found that some genes that had previously been identified in relation to AD were associated with different dementia-associated brain lesions. Finally, we found that the various brain lesions differ in the proportion that can be attributed to genetic vs. environmental differences. These results support that the pathway to a diagnosis of dementia can be caused by multiple factors and are an important step in beginning to identify individually based dementia treatments. Show less
Vascular damage, including cerebral amyloid angiopathy (CAA) and non-amyloid cerebral small vessel disease (CSVD), has been linked to glymphatic dysfunction, which may contribute to Alzheimer's diseas Show more
Vascular damage, including cerebral amyloid angiopathy (CAA) and non-amyloid cerebral small vessel disease (CSVD), has been linked to glymphatic dysfunction, which may contribute to Alzheimer's disease (AD) pathology and cognitive decline. We investigated the associations among vascular damage, glymphatic function measured by the DTI-ALPS (Diffusion Tensor Imaging-Analysis Along the Perivascular Space) index, AD plasma biomarkers, and cognitive decline. This study includes 1,249 participants recruited from Samsung Medical Center. We performed linear regression analysis to identify factors associated with the DTI-ALPS index. Further, linear regression analysis with vascular imaging markers, including CAA and CSVD summary scores, as predictors and DTI-ALPS index as an outcome was performed to investigate the effect of vascular pathology on glymphatic function. We conducted mediation analyses to investigate whether the DTI-ALPS index mediates the effect of vascular imaging markers on plasma biomarkers (phosphorylated tau 217 [p-tau 217], glial fibrillary acidic protein [GFAP], and neurofilament light chain [NFL]). Additionally, mediation analyses with the DTI-ALPS index as a predictor, each plasma biomarker as a mediator, and annual MMSE or CDR-SOB change as an outcome to investigate whether plasma biomarkers mediate the effect of the DTI-ALPS index on longitudinal cognitive decline. First, the DTI-ALPS index was negatively associated with both CAA (β [95% CI] = -0.163 [-0.214, -0.112], p < 0.0001) and CSVD (β [95% CI] = -0.195 [-0.247, -0.143], p < 0.0001) summary scores after controlling for age, sex, BMI status, and APOE genotype. Second, the DTI-ALPS index fully mediated the relationship between these vascular markers and p-tau 217 (CSVD summary score, indirect effect β [95% CI] = 0.016 [0.010, 0.023], p < 0.001; CAA summary score, indirect effect β [95% CI] = 0.013 [0.008, 0.020], p < 0.001) and GFAP (CSVD summary score, indirect effect β [95% CI] = 0.015 [0.008, 0.022], p < 0.001; CAA summary score, indirect effect β [95% CI] = 0.012 [0.007, 0.019], p < 0.001), while partially mediating the relationship for NFL, regardless of Aβ uptake on PET. Finally, the DTI-ALPS index was significantly associated with cognitive decline and this association was partially mediated by plasma biomarkers. These findings highlight glymphatic dysfunction as a key mechanism linking vascular pathology with tau, inflammation and neurodegeneration, independent of Aβ uptakes. Show less
BackgroundOthers have examined heterogeneity in Alzheimer's disease (AD); however, few have used longitudinal data while accounting for variation in disease stage. We used latent classes to model hete Show more
BackgroundOthers have examined heterogeneity in Alzheimer's disease (AD); however, few have used longitudinal data while accounting for variation in disease stage. We used latent classes to model heterogeneity in the trajectories of three cognitive domains (memory, language, and executive functioning) starting at AD dementia diagnosis.ObjectiveOur aim was to describe the patterns of heterogeneity in cognitive decline across cognitive domains during the course of AD and to contextualize our findings by assessing associations with demographic factors and neuropathological measures.MethodsWe used cognitive data from the Religious Orders Study, the Rush Memory and Aging Project, and the Minority Aging Research Study in a multi-dimensional joint latent class mixed model, which allowed us to estimate cognitive trajectories that varied across cognitive domains and latent classes. We accounted for the uncertainty in latent class assignment and corrected for multiple hypotheses when assessing the association of the latent classes with demographic and neuropathological variables.ResultsWe identified five latent classes differentiated by level of impairment (high to low) and rate of decline (slow to fast). Within each latent class, the pattern of decline did not differ substantially across cognitive domains. Classes were associated with Show less
Aniridia, driven by PAX6 mutations, causes aniridia-associated keratopathy (AAK), a progressive condition linked to limbal stem cell deficiency. A major hurdle to developing targeted therapies for AAK Show more
Aniridia, driven by PAX6 mutations, causes aniridia-associated keratopathy (AAK), a progressive condition linked to limbal stem cell deficiency. A major hurdle to developing targeted therapies for AAK is the incomplete understanding of the molecular abnormalities in affected corneas. To address this, we leveraged Pax6± (Pax6 het) mice, a model of AAK, and applied single-cell RNA sequencing (scRNA-seq) to profile the transcriptomic changes at a single-cell resolution. ScRNA-seq of corneal/limbal tissues of wild type (WT) and Pax6 het mice were conducted. Immunostaining was performed to examine the expression of specific markers for stem cells. ScRNA-seq identified a quiescent limbal epithelial stem cell (LESC)-like cell cluster and an early transient amplifying cell (eTAC)-like cluster. An increase in the cell numbers in these two clusters in the Pax6 het mouse corneas was observed. Immunostaining detected a marked increase in markers for these two clusters including Tmem176b, Apoe, and Krt15 in the corneal epithelium of Pax6 het mice, suggesting an increase of these LESC/eTA-like cells into the corneal epithelium. The Pax6 deficiency inhibited the expression of genes involved in cell proliferation in the eTAC-like cluster as well as the expression of genes related to corneal epithelial cell fate and differentiation compared with WT mice. Our single cell transcriptome of the limbus and cornea of Pax6 het mice indicates that AAK may be due to the increase of dysfunctional stem/eTACs with defects in committing to a corneal epithelial cell fate and differentiation. Show less
Decreasing body mass index (BMI) from midlife to late life has been linked to increased Alzheimer's disease (AD) risk and cognitive decline; however, the association with in vivo AD pathology remains Show more
Decreasing body mass index (BMI) from midlife to late life has been linked to increased Alzheimer's disease (AD) risk and cognitive decline; however, the association with in vivo AD pathology remains unclear. This study aimed to clarify the relationship between midlife-to-late-life BMI changes and in vivo AD pathologies, specifically amyloid-β (Aβ), tau, and AD-signature region cerebral glucose metabolism (AD-CM). This observational cohort study included non-demented older adults recruited from the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer’s Disease (KBASE) between January 2014 and December 2020. Participants underwent clinical evaluations and positron emission tomography (PET) imaging to measure brain Aβ, tau, and AD-CM. Midlife BMI was retrospectively estimated from self-reported weight at ages 40–50 years, while late-life BMI was measured during the study. Participants were categorized based on BMI changes as decreasing (≤ − 4%), stable (− 4% to < 4%), or increasing (≥ 4%). Associations between BMI patterns and AD pathologies were analyzed using multiple linear regression models. A total of 268 participants (mean age 66.6 ± 7.9 years; 56.3% women; 22.5% APOE ε4 carriers) were analyzed. Higher midlife BMI correlated significantly with lower AD-CM (β = − 0.009; 95% CI, − 0.015 to − 0.003; A decreasing BMI trajectory from midlife to late life is associated with enhanced AD-related neurodegeneration, underscoring the clinical importance of monitoring long-term body weight changes in relation to Alzheimer's disease pathophysiology. The online version contains supplementary material available at 10.1186/s13195-026-01967-z. Show less
Impaired glymphatic function is considered an important characteristic of cognitive decline, but the role of tau pathology as a mediator remains unclear. This study investigated whether tau burden med Show more
Impaired glymphatic function is considered an important characteristic of cognitive decline, but the role of tau pathology as a mediator remains unclear. This study investigated whether tau burden mediates the association between diffusion tensor image analysis along the perivascular space (DTI-ALPS) and cognitive impairment or brain atrophy. Also, we explored whether DTI-ALPS index predicts longitudinal cognitive deterioration over time. We included 144 individuals with mild cognitive impairment (MCI), Alzheimer's disease dementia (ADD), and other dementia, or normal cognition. All participants underwent 3.0-Tesla MRI, DTI-ALPS index was significantly lower in cognitively impaired individuals compared to cognitively normal (CN) participants. Lower DTI-ALPS index was associated with higher tau burden and worse cognitive function. Tau burden was also inversely associated with cognition. Mediation analysis indicated that tau burden accounted for approximately 21-27% of the association between DTI-ALPS and cognition. Longitudinal analysis showed baseline lower DTI-ALPS index also predicted faster longitudinal cognitive decline. Our findings suggest that the DTI-ALPS index is an indirect marker of glymphatic dysfunction associated with tau accumulation and cognitive decline. Tau pathology may partially link compromised glymphatic clearance to cognitive impairment. Show less
Epigenetic clocks associate with neuropathology and Alzheimer's disease (AD) clinical risk, but findings are mixed regarding whether clocks associate with blood-based biomarkers and in non-European po Show more
Epigenetic clocks associate with neuropathology and Alzheimer's disease (AD) clinical risk, but findings are mixed regarding whether clocks associate with blood-based biomarkers and in non-European populations. We calculated biological age and age acceleration from blood methylation data in 704 older Hispanic adults and tested associations with clinical diagnosis and antemortem biomarker levels. Age acceleration was significantly associated with sex, clinical diagnosis, and levels of eight plasma biomarkers, including P-tau217 levels. Additionally, biomarker associations trended more significantly among APOE-ε4 non-carriers. We also identified that methylation levels in CD4 and CD8 T-cell types are associated with age acceleration. We demonstrated that biological age acceleration, measured in blood, in a Hispanic cohort enriched for preclinical individuals, can stratify clinical AD risk and is associated with plasma AD biomarker levels. Blood-based aging clocks associate with Alzheimer's disease plasma biomarker levels. Biological aging appears relevant to pathological aging in apolipoprotein E (APOE) -ε4 non-carriers. Immune T-cell composition relates to biological aging. Show less
"SuperAgers" are oldest-old adults (ages 80+) whose memory performance more closely resembles middle-aged adults. The present study examined apolipoprotein E (APOE) allele frequency in non-Hispanic Bl Show more
"SuperAgers" are oldest-old adults (ages 80+) whose memory performance more closely resembles middle-aged adults. The present study examined apolipoprotein E (APOE) allele frequency in non-Hispanic Black (NHB) and non-Hispanic White (NHW) SuperAgers compared to controls and Alzheimer's disease dementia cases. In 18,080 participants from eight cohorts, harmonized clinical diagnostics and memory, executive function, and language domain scores were used to identify SuperAgers, cases, and controls across age-defined bins. NHW SuperAgers had significantly lower frequency of APOE-ε4 alleles and higher frequency of APOE-ε2 alleles compared to all cases and controls, including oldest-old controls. Similar patterns were found in a small yet substantial sample of NHB SuperAgers; however, not all comparisons with controls reached significance. We demonstrated strong evidence that APOE allele frequency relates to SuperAger status. Further research is needed with a larger sample of NHB SuperAgers to determine if mechanisms conferring cognitive resilience differ across race groups. Apolipoprotein E (APOE) allele frequency differs between SuperAgers and cases APOE allele frequency differs between non-Hispanic White SuperAgers and controls The relationship of APOE and non-Hispanic Black SuperAger status is unclear. Show less
Alzheimer's disease (AD) is the leading cause of dementia, characterized by the deposition of amyloid-β plaques and neurofibrillary tangles composed of hyperphosphorylated tau. Seizures have also emer Show more
Alzheimer's disease (AD) is the leading cause of dementia, characterized by the deposition of amyloid-β plaques and neurofibrillary tangles composed of hyperphosphorylated tau. Seizures have also emerged as a prevalent clinical feature of AD and are associated with APOE4, the major genetic risk factor of AD. However, the mechanism by which APOE4 induces seizures and neuronal hyperexcitability is incompletely understood. We discovered that human APOE4 targeted replacement mice showed increased seizure severity and seizure-induced death at 5.5-7 but not 2-3 months of age compared to APOE3 mice using the kainic acid model of status epilepticus which preferentially arises from the hippocampus. While Tau burden alone did not alter seizure susceptibility in mice, APOE4 together with Tau burden enhanced seizure severity in female mice. Notably, APOE4 was associated with decreased hippocampal levels of sodium/potassium-ATPase, ATP-generating glycolytic enzymes, including phosphoglycerate kinase 1 (PGK1) and pyruvate kinase M, and ATP. While inhibition of Na Show less
Plasma biomarkers of Alzheimer's disease (AD) pathology are frequently tested in specialized research settings, which limits the generalizability of findings. Using electronic health records and banke Show more
Plasma biomarkers of Alzheimer's disease (AD) pathology are frequently tested in specialized research settings, which limits the generalizability of findings. Using electronic health records and banked plasma, we evaluated plasma biomarkers-phosphorylated tau 217 (p-tau Participants (n = 617; 44% Black/African American; 41% female) were selected from the University of Pennsylvania Medicine BioBank with plasma assayed using Fujirebio Lumipulse. International Classification of Diseases (ICD) Ninth and Tenth Revision codes determined AD dementia (ADD) (n = 43), mild-cognitive impairment (MCI) (n = 140), unspecified/non-AD cognitive impairment (CI) (n = 106), and cognitively normal cases (n = 328), and other medical histories. APOE ε4, body mass index (BMI), metrics of kidney function (eg, estimated glomerular filtration rate [eGFR]), and liver disease were derived from electronic health records. Multivariable models identified factors related to plasma levels. Previously established cutpoints classified AD status ("AD+," "AD-," or "Intermediate"). Plasma p-tau In this real-world dataset, we identified effects of multimorbidities on plasma biomarkers, especially kidney function. The p-tau Show less
BackgroundAmyloid accumulation and degeneration of the cholinergic white matter pathways are key factors in early Alzheimer's disease pathogenesis and progression. However, the relationship between th Show more
BackgroundAmyloid accumulation and degeneration of the cholinergic white matter pathways are key factors in early Alzheimer's disease pathogenesis and progression. However, the relationship between them remains unclear.ObjectiveTo investigate the association between amyloid accumulation, the integrity of cholinergic white matter pathways, and cognitive performance.MethodsThis cross-sectional study recruited 109 individuals, including 37 controls with normal cognition and 72 patients with early Alzheimer's disease. All participants underwent neuropsychological testing: the Mini-Mental Status Examination (MMSE), Clinical Dementia Rating scale with sum of box (CDR-SB), and verbal fluency tests. Cholinergic white matter integrity and amyloid burden were assessed through diffusion tensor imaging study (DTI) and amyloid positron emission tomography (PET). Stepwise linear regression analyses were performed. Partial correlations between amyloid burden and cholinergic integrity were also evaluated according to apolipoprotein E4 ( Show less
Circulating metabolites can identify biochemical risk factors related to Alzheimer's disease (AD). We measured plasma metabolites in 1,068 participants of Caribbean Hispanic ancestry (250 patients wit Show more
Circulating metabolites can identify biochemical risk factors related to Alzheimer's disease (AD). We measured plasma metabolites in 1,068 participants of Caribbean Hispanic ancestry (250 patients with AD and 818 healthy controls) across 2 cohorts and analyzed their relationship with clinical AD, biomarker-supported AD and plasma biomarkers (P-tau181, P-tau217, P-tau231 and Aβ42:Aβ40). Amino acid metabolism pathways were enriched among metabolites associated with P-tau biomarkers, whereas sialic acid and N-glycan pathways were associated with Aβ42:Aβ40. Through several dimensionality reduction approaches, we identified an APOE-ε4 dependent relationship between lysophosphatidylcholines (lysoPCs) carrying polyunsaturated fatty acids and biomarker-supported AD and P-tau biomarkers. In an independent dataset of 110 postmortem brain tissues from non-Hispanic white participants, lysoPCs in the brain were also associated with AD neuropathological features. Our results show that biomarker-based diagnostic criteria identified an APOE-ε4 dependent association with lysoPCs, which play a critical role in the transport of neuroprotective polyunsaturated fatty acids into the brain, and AD. Show less
Apolipoprotein E (ApoE) mediates the bidirectional transport of lipids between cells. In the brain, this includes the transfer of lipids from neurons to glia. ApoE4, a major risk factor for Alzheimer' Show more
Apolipoprotein E (ApoE) mediates the bidirectional transport of lipids between cells. In the brain, this includes the transfer of lipids from neurons to glia. ApoE4, a major risk factor for Alzheimer's disease, impairs this transport pathway, increasing risk for neurodegeneration. ApoE2 and ApoE3 Christchurch (ApoE3Ch) confer resistance to disease, yet little is known regarding how these variants affect lipid trafficking. Here, we explored how lipoprotein particles containing different ApoE isoforms affect neuronal health. We demonstrate that ApoE2 and ApoE3Ch particles protect neurons from ferroptosis by extracting oxidized unsaturated lipids through the ABCA7 transporter. ApoE4 particles, on the other hand, exacerbate the effects of these toxic lipids, leading to endolysosomal dysfunction. By reducing the oxidized lipid burden in ApoE4 neurons, ApoE2 and ApoE3Ch particles rescue endolysosomal function and restore defects in neuronal activity caused by excitotoxicity. Our findings reveal how ApoE2 and ApoE3Ch help protect neurons from neurodegeneration. Show less
Alzheimer's disease (AD) is marked by amyloid-β (Aβ) accumulation, tau pathology, and neuroinflammation. The β-site APP cleaving enzyme 1 (BACE1) is a key driver of Aβ production, while the NLRP3 infl Show more
Alzheimer's disease (AD) is marked by amyloid-β (Aβ) accumulation, tau pathology, and neuroinflammation. The β-site APP cleaving enzyme 1 (BACE1) is a key driver of Aβ production, while the NLRP3 inflammasome mediates microglial inflammatory responses. Histone deacetylase 6 (HDAC6), a cytoplasmic deacetylase, is upregulated in AD, yet its role in disease mechanisms remains unclear. Here, we show that HDAC6 promotes BACE1 protein stability through direct deacetylation of its C-terminal lysine (K501), thereby increasing Aβ production. HDAC6 also facilitated NLRP3 inflammasome activation in microglia, increasing IL-1β production in a catalytic domain-dependent manner. HDAC6 deficiency in 5xFAD mice reduced BACE1 accumulation, Aβ deposition, ASC speck formation, and IL-1β levels, accompanied by improved cognitive performance. Transcriptomic profiling further revealed downregulation of disease-associated microglial and neurotoxic astrocyte signatures alongside enrichment of synaptic pathways. These findings establish HDAC6 as a dual regulator of Aβ production and neuroinflammation, highlighting it as a promising therapeutic target in AD. Show less
Diabetes is a major risk factor for diabetic encephalopathy (DE), which is closely associated with sporadic Alzheimer's disease. Folic acid (FA) receptor signaling can suppress generation of neuropath Show more
Diabetes is a major risk factor for diabetic encephalopathy (DE), which is closely associated with sporadic Alzheimer's disease. Folic acid (FA) receptor signaling can suppress generation of neuropathogenic amyloid-beta (Aβ) induced by high extracellular glucose, suggesting that enhanced activation of this pathway could be a therapeutic strategy against DE-associated dementia, but the precise molecular signaling mechanisms are unclear. We report that high glucose levels increased the expression of amyloid precursor protein (APP) and β-secretase (BACE1) in cultured neurons and concomitantly induced amyloidogenesis, while FA treatment suppressed high glucose-stimulated expression of APP and BACE1, Aβ release, and accumulation of mitochondrial reactive oxygen species. Expression of nuclear factor erythroid 2-related factor 2 (Nrf2) was minimal under high glucose conditions, but was significantly upregulated together with downstream antioxidant enzymes following FA co-treatment. High glucose stimulation also increased folate receptor 1 (FOLR1) mRNA expression, suggesting a compensatory protective response. While treatment with 5-methyltetrahydrofolate (5-MTHF), the activated form of folate, did not significantly alter high glucose-induced upregulation of APP and BACE1, knockdown of FOLR1 mRNA reduced high glucose-stimulated Nrf2 expression and further augmented APP and BACE1 expression under high glucose conditions. Treatment with the STAT3 inhibitor 5'15-DPP also abolished high glucose-stimulated Nrf2 expression and increased APP and BACE1 expression levels. These findings indicate that FA/FOLR1 activation suppresses high glucose-induced amyloidogenesis by mitigating mitochondrial oxidative stress via STAT3/Nrf2 pathway signaling. In conclusion, present study suggests that the FA/FOLR1/STAT3/Nrf2 pathway is an effective therapeutic target for DE. Show less
Aberrant deposition of β-amyloid (Aβ) and hyperphosphorylated tau, along with neuroinflammation, are key drivers of Alzheimer's disease (AD) pathology. Here, we identify ramalin, a natural antioxidant Show more
Aberrant deposition of β-amyloid (Aβ) and hyperphosphorylated tau, along with neuroinflammation, are key drivers of Alzheimer's disease (AD) pathology. Here, we identify ramalin, a natural antioxidant, as a promising therapeutic agent that alleviates AD pathology by modulating β-site APP cleaving enzyme 1 (BACE1), histone deacetylase 6 (HDAC6), and the mitogen-activated protein kinases (MAPK) pathway. Ramalin reduced BACE1 protein levels, independently of its transcription, translation, or enzymatic activity, an effect mediated by inhibition of HDAC6. Consistently, HDAC6 knockout similarly decreased BACE1 levels, highlighting HDAC6 as a key regulator of BACE1. Ramalin further suppressed neuroinflammatory responses by downregulating inducible nitric oxide synthase (iNOS) and the NLR family pyrin domain containing 3 (NLRP3) inflammasome. In AD mouse models, ramalin treatment significantly attenuated neuroinflammation, Aβ plaque burden, and tau hyperphosphorylation, while improving cognitive performance. Notably, ramalin reversed Aβ oligomer-induced synaptic transmission impairment and restored synaptic vesicle recycling in hippocampal neurons. Transcriptomic analysis identified modulation of the MAPK pathway, with reduced phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) implicated in tau pathology. These findings establish ramalin as a disease-modifying intervention that provides neuroprotection through concurrent regulation of BACE1, HDAC6, and MAPK signaling pathway. Collectively, our findings highlight ramalin as a compelling disease-modifying candidate with the potential to drive a breakthrough approach targeting AD pathology. Show less
Contact sports, including rugby union, are associated with higher rates of neurodegenerative dementia, due to various underlying pathologies such as Alzheimer's disease (AD) and chronic traumatic ence Show more
Contact sports, including rugby union, are associated with higher rates of neurodegenerative dementia, due to various underlying pathologies such as Alzheimer's disease (AD) and chronic traumatic encephalopathy (CTE). New ultrasensitive multiplexed immunoassays may clarify disease mechanisms after repetitive head impacts (RHI) and traumatic brain injury, potentially aiding risk-stratification, early diagnosis and dementia treatment. Midlife participants in the ABHC cohort underwent plasma biomarker quantification (NULISA - NUcleic acid Linked Immuno-Sandwich Assay; n=124 markers), 3T MRI, trauma exposure ascertainment and phenotyping. Regressions quantified exposure-specific protein expression, relationship to trauma (including position) and brain atrophy, using cluster analysis to test correlates of traumatic encephalopathy syndrome (TES). 197 former elite rugby players and 33 controls were assessed. 24 (12.2%) met criteria for TES but none had dementia. Ex-players returned reduced plasma glial fibrillary acidic protein (GFAP), kallikrein-6 (KLK6) and synaptosomal-associated protein 25 (SNAP25). Ex-forwards specifically showed reduced plasma beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), amyloid beta-38 (Aβ38), and increased phospho-tau Ex-players showed distinctive plasma biomarker changes, more prominently in ex-forwards, possibly reflecting greater RHI exposure. Plasma KLK6, an endothelial serine protease, was reduced across the ex-player group, with potential diagnostic or prognostic utility in future. Reduced GFAP and SNAP25 in ex-forwards has an uncertain basis, while elevated p-tau- Show less
Hypercholesterolemia is a major risk factor for cardiovascular disease, necessitating the development of effective and safe lipid-lowering interventions. This study evaluated the antihypercholesterole Show more
Hypercholesterolemia is a major risk factor for cardiovascular disease, necessitating the development of effective and safe lipid-lowering interventions. This study evaluated the antihypercholesterolemic effects of KGC11 Show less
Development of therapies for CLN3 disease, a rare pediatric lysosomal storage disorder, has been hindered by the lack of etiological insights and translatable biomarkers to clinics. We used a deep mul Show more
Development of therapies for CLN3 disease, a rare pediatric lysosomal storage disorder, has been hindered by the lack of etiological insights and translatable biomarkers to clinics. We used a deep multi-omics approach to discover blood-based biomarkers using longitudinal serum samples from a porcine model of CLN3 disease. Comprehensive metabolomics was combined with a nanoparticle-based LC-MS-based proteomic profiling coupled with TMTpro 18-plex to generate quantitative data on 769 metabolites and 2634 proteins, collectively the most exhaustive multi-omics profile conducted on serum from a porcine model. This was previously impossible due to lack of efficient deep serum proteome profiling technologies compatible with model organisms. Here we show that the presymptomatic disease state is characterized by elevations in glycerophosphodiester species and lysosomal proteases, while later timepoints are enriched with species involved in immune cell activation and sphingolipid metabolism. Cathepsin S (CTSS), Cathepsin B (CTSB), glycerophosphoinositol, and glycerophosphoethanolamine captured a large portion of the genotype-correlated variation between healthy and diseased animals, suggesting that an index score based on these analytes could have great utility in the clinic. This study's findings demonstrate the potential of deep multi-omics profiling for uncovering disease-specific biomarkers, providing valuable insights for understanding disease and facilitating the identification of potential drug targets, thus offering valuable insights for therapeutic interventions. Show less