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1.
Cell Genom ; 4(5): 100555, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38697121

RESUMO

The complex pathobiology of late-onset Alzheimer's disease (AD) poses significant challenges to therapeutic and preventative interventions. Despite these difficulties, genomics and related disciplines are allowing fundamental mechanistic insights to emerge with clarity, particularly with the introduction of high-resolution sequencing technologies. After all, the disrupted processes at the interface between DNA and gene expression, which we call the broken AD genome, offer detailed quantitative evidence unrestrained by preconceived notions about the disease. In addition to highlighting biological pathways beyond the classical pathology hallmarks, these advances have revitalized drug discovery efforts and are driving improvements in clinical tools. We review genetic, epigenomic, and gene expression findings related to AD pathogenesis and explore how their integration enables a better understanding of the multicellular imbalances contributing to this heterogeneous condition. The frontiers opening on the back of these research milestones promise a future of AD care that is both more personalized and predictive.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Humanos , Genoma Humano , Genômica/métodos , Animais
2.
J Prev Alzheimers Dis ; 11(3): 730-738, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706289

RESUMO

BACKGROUND: Serum-measured fragments of Tau cleaved by ADAM-10 (Tau-A) and Caspase-3 (Tau-C) have been found linked to change in cognitive function and risk of dementia. OBJECTIVES: 1) To determine the discriminatory abilities of Tau-A, and Tau-C in subjects with either mild cognitive impairment (MCI) due to Alzheimer's disease (AD) or AD dementia compared to a control group. 2) To determine if there is a relation between Tau-A, and Tau-C and established cerebrospinal fluid (CSF) markers of AD- ß-Amyloid1-42 (AB42), Phosphorylated-tau-181 (p-tau), and total-tau. 3) To determine if Tau-A and Tau-C are associated with progression rate from MCI due to AD to AD dementia. DESIGN: Cross-sectional and a substudy using a retrospective cohort design. SETTING: Memory clinic derived subjects contributing to the Danish Dementia Biobank. PARTICIPANTS: Cognitively unimpaired subjects (n=49), patients with mild cognitive impairment (MCI) due to AD (n=45), and Alzheimer's dementia (n=52). MEASUREMENTS: Competitive enzyme-linked immunosorbent assay (ELISA)-measured serum levels of Tau-A, and Tau-C. RESULTS: The ratio between Tau-A and Tau-C differed between the three groups (p=0.015). Age- and sex-adjusted Tau-A differed between groups with lower ratios being associated with more severe disease (p=0.023). Tau-C was trending towards significant correlation to CSF-levels of AB42 (Pearson correlation coefficient 0.164, p=0.051). Those with Tau-C-levels in the 2nd quartile had a hazard ratio (HR) of 2.91 (95% CI 1.01 - 8.44, p=0.04) of progression compared to those in the 1st quartile. Those in the 3rd quartile was found to have a borderline significant (p=0.055) HR of 2.63 (95% CI 0.98 - 7.05) when compared to those in the lowest quartile. CONCLUSIONS: Tau-A and the ratio between Tau-A and Tau-C showed significant differences between groups and were correlated to CSF-AB42. Tau-C values in the middle range were associated with faster progression from MCI to dementia. This pilot study adds to the mounting data suggesting serum-measured Tau-A and Tau-C as biomarkers useful in relation to diagnosis and progression rate in AD but need further validation.


Assuntos
Doença de Alzheimer , Biomarcadores , Disfunção Cognitiva , Progressão da Doença , Proteínas tau , Humanos , Proteínas tau/sangue , Proteínas tau/líquido cefalorraquidiano , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico , Masculino , Feminino , Idoso , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Estudos Transversais , Estudos Retrospectivos , Pessoa de Meia-Idade , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Demência/sangue , Estudos de Coortes , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/líquido cefalorraquidiano
3.
Nat Commun ; 15(1): 3872, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719797

RESUMO

The gut microbiota and microglia play critical roles in Alzheimer's disease (AD), and elevated Bacteroides is correlated with cerebrospinal fluid amyloid-ß (Aß) and tau levels in AD. We hypothesize that Bacteroides contributes to AD by modulating microglia. Here we show that administering Bacteroides fragilis to APP/PS1-21 mice increases Aß plaques in females, modulates cortical amyloid processing gene expression, and down regulates phagocytosis and protein degradation microglial gene expression. We further show that administering Bacteroides fragilis to aged wild-type male and female mice suppresses microglial uptake of Aß1-42 injected into the hippocampus. Depleting murine Bacteroidota with metronidazole decreases amyloid load in aged 5xFAD mice, and activates microglial pathways related to phagocytosis, cytokine signaling, and lysosomal degradation. Taken together, our study demonstrates that members of the Bacteroidota phylum contribute to AD pathogenesis by suppressing microglia phagocytic function, which leads to impaired Aß clearance and accumulation of amyloid plaques.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Modelos Animais de Doenças , Camundongos Transgênicos , Microglia , Fagocitose , Placa Amiloide , Animais , Microglia/metabolismo , Microglia/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/microbiologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Placa Amiloide/metabolismo , Feminino , Camundongos , Masculino , Bacteroides fragilis/metabolismo , Microbioma Gastrointestinal , Humanos , Camundongos Endogâmicos C57BL , Hipocampo/metabolismo , Hipocampo/patologia
4.
NPJ Syst Biol Appl ; 10(1): 50, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724582

RESUMO

Connectome studies have shown how Alzheimer's disease (AD) disrupts functional and structural connectivity among brain regions. But the molecular basis of such disruptions is less studied, with most genomic/transcriptomic studies performing within-brain-region analyses. To inspect how AD rewires the correlation structure among genes in different brain regions, we performed an Inter-brain-region Differential Correlation (Inter-DC) analysis of RNA-seq data from Mount Sinai Brain Bank on four brain regions (frontal pole, superior temporal gyrus, parahippocampal gyrus and inferior frontal gyrus, comprising 264 AD and 372 control human post-mortem samples). An Inter-DC network was assembled from all pairs of genes across two brain regions that gained (or lost) correlation strength in the AD group relative to controls at FDR 1%. The differentially correlated (DC) genes in this network complemented known differentially expressed genes in AD, and likely reflects cell-intrinsic changes since we adjusted for cell compositional effects. Each brain region used a distinctive set of DC genes when coupling with other regions, with parahippocampal gyrus showing the most rewiring, consistent with its known vulnerability to AD. The Inter-DC network revealed master dysregulation hubs in AD (at genes ZKSCAN1, SLC5A3, RCC1, IL17RB, PLK4, etc.), inter-region gene modules enriched for known AD pathways (synaptic signaling, endocytosis, etc.), and candidate signaling molecules that could mediate region-region communication. The Inter-DC network generated in this study is a valuable resource of gene pairs, pathways and signaling molecules whose inter-brain-region functional coupling is disrupted in AD, thereby offering a new perspective of AD etiology.


Assuntos
Doença de Alzheimer , Encéfalo , Redes Reguladoras de Genes , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Humanos , Redes Reguladoras de Genes/genética , Encéfalo/metabolismo , Conectoma/métodos , Transcriptoma/genética , Perfilação da Expressão Gênica/métodos , Masculino , Feminino , Idoso
5.
BMC Health Serv Res ; 24(1): 607, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724975

RESUMO

BACKGROUND: Primary health care has a central role in dementia detection, diagnosis, and management, especially in low-resource rural areas. Care navigation is a strategy to improve integration and access to care, but little is known about how navigators can collaborate with rural primary care teams to support dementia care. In Saskatchewan, Canada, the RaDAR (Rural Dementia Action Research) team partnered with rural primary health care teams to implement interprofessional memory clinics that included an Alzheimer Society First Link Coordinator (FLC) in a navigator role. Study objectives were to examine FLC and clinic team member perspectives of the impact of FLC involvement, and analysis of Alzheimer Society data comparing outcomes associated with three types of navigator-client contacts. METHODS: This study used a mixed-method design. Individual semi-structured interviews were conducted with FLC (n = 3) and clinic team members (n = 6) involved in five clinics. Data were analyzed using thematic inductive analysis. A longitudinal retrospective analysis was conducted with previously collected Alzheimer Society First Link database records. Memory clinic clients were compared to self- and direct-referred clients in the geographic area of the clinics on time to first contact, duration, and number of contacts. RESULTS: Three key themes were identified in both FLC and team interviews: perceived benefits to patients and families of FLC involvement, benefits to memory clinic team members, and impact of rural location. Whereas other team members assessed the patient, only FLC focused on caregivers, providing emotional and psychological support, connection to services, and symptom management. Face-to-face contact helped FLC establish a relationship with caregivers that facilitated future contacts. Team members were relieved knowing caregiver needs were addressed and learned about dementia subtypes and available services they could recommend to non-clinic clients with dementia. Although challenges of rural location included fewer available services and travel challenges in winter, the FLC role was even more important because it may be the only support available. CONCLUSIONS: FLC and team members identified perceived benefits of an embedded FLC for patients, caregivers, and themselves, many of which were linked to the FLC being in person.


Assuntos
Atenção Primária à Saúde , Serviços de Saúde Rural , Humanos , Atenção Primária à Saúde/organização & administração , Saskatchewan , Serviços de Saúde Rural/organização & administração , Feminino , Masculino , Doença de Alzheimer/terapia , Doença de Alzheimer/psicologia , Estudos Retrospectivos , Navegação de Pacientes/organização & administração , Pesquisa Qualitativa , Entrevistas como Assunto , Idoso , Equipe de Assistência ao Paciente/organização & administração
6.
PLoS One ; 19(5): e0303375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38728348

RESUMO

Hearing loss is a pivotal risk factor for dementia. It has recently emerged that a disruption in the intercommunication between the cochlea and brain is a key process in the initiation and progression of this disease. However, whether the cochlear properties can be influenced by pathological signals associated with dementia remains unclear. In this study, using a mouse model of Alzheimer's disease (AD), we investigated the impacts of the AD-like amyloid ß (Aß) pathology in the brain on the cochlea. Despite little detectable change in the age-related shift of the hearing threshold, we observed quantitative and qualitative alterations in the protein profile in perilymph, an extracellular fluid that fills the path of sound waves in the cochlea. Our findings highlight the potential contribution of Aß pathology in the brain to the disturbance of cochlear homeostasis.


Assuntos
Doença de Alzheimer , Cóclea , Modelos Animais de Doenças , Perilinfa , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Camundongos , Perilinfa/metabolismo , Cóclea/metabolismo , Cóclea/patologia , Peptídeos beta-Amiloides/metabolismo , Camundongos Transgênicos , Perda Auditiva/metabolismo , Perda Auditiva/patologia
7.
FASEB J ; 38(10): e23659, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38733301

RESUMO

HDAC3 inhibition has been shown to improve memory and reduce amyloid-ß (Aß) in Alzheimer's disease (AD) models, but the underlying mechanisms are unclear. We investigated the molecular effects of HDAC3 inhibition on AD pathology, using in vitro and ex vivo models of AD, based on our finding that HDAC3 expression is increased in AD brains. For this purpose, N2a mouse neuroblastoma cells as well as organotypic brain cultures (OBCSs) of 5XFAD and wild-type mice were incubated with various concentrations of the HDAC3 selective inhibitor RGFP966 (0.1-10 µM) for 24 h. Treatment with RGFP966 or HDAC3 knockdown in N2a cells was associated with an increase on amyloid precursor protein (APP) and mRNA expressions, without alterations in Aß42 secretion. In vitro chromatin immunoprecipitation analysis revealed enriched HDAC3 binding at APP promoter regions. The increase in APP expression was also detected in OBCSs from 5XFAD mice incubated with 1 µM RGFP966, without changes in Aß. In addition, HDAC3 inhibition resulted in a reduction of activated Iba-1-positive microglia and astrocytes in 5XFAD slices, which was not observed in OBCSs from wild-type mice. mRNA sequencing analysis revealed that HDAC3 inhibition modulated neuronal regenerative pathways related to neurogenesis, differentiation, axonogenesis, and dendritic spine density in OBCSs. Our findings highlight the complexity and diversity of the effects of HDAC3 inhibition on AD models and suggest that HDAC3 may have multiple roles in the regulation of APP expression and processing, as well as in the modulation of neuroinflammatory and neuroprotective genes.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Modelos Animais de Doenças , Histona Desacetilases , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Camundongos , Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Inibidores de Histona Desacetilases/farmacologia , Humanos , Camundongos Transgênicos , Encéfalo/metabolismo , Encéfalo/patologia , Peptídeos beta-Amiloides/metabolismo , Linhagem Celular Tumoral , Masculino , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Fenilenodiaminas/farmacologia , Acrilamidas
8.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38711368

RESUMO

Common genetic variants and susceptibility loci associated with Alzheimer's disease (AD) have been discovered through large-scale genome-wide association studies (GWAS), GWAS by proxy (GWAX) and meta-analysis of GWAS and GWAX (GWAS+GWAX). However, due to the very low repeatability of AD susceptibility loci and the low heritability of AD, these AD genetic findings have been questioned. We summarize AD genetic findings from the past 10 years and provide a new interpretation of these findings in the context of statistical heterogeneity. We discovered that only 17% of AD risk loci demonstrated reproducibility with a genome-wide significance of P < 5.00E-08 across all AD GWAS and GWAS+GWAX datasets. We highlighted that the AD GWAS+GWAX with the largest sample size failed to identify the most significant signals, the maximum number of genome-wide significant genetic variants or maximum heritability. Additionally, we identified widespread statistical heterogeneity in AD GWAS+GWAX datasets, but not in AD GWAS datasets. We consider that statistical heterogeneity may have attenuated the statistical power in AD GWAS+GWAX and may contribute to explaining the low repeatability (17%) of genome-wide significant AD susceptibility loci and the decreased AD heritability (40-2%) as the sample size increased. Importantly, evidence supports the idea that a decrease in statistical heterogeneity facilitates the identification of genome-wide significant genetic loci and contributes to an increase in AD heritability. Collectively, current AD GWAX and GWAS+GWAX findings should be meticulously assessed and warrant additional investigation, and AD GWAS+GWAX should employ multiple meta-analysis methods, such as random-effects inverse variance-weighted meta-analysis, which is designed specifically for statistical heterogeneity.


Assuntos
Doença de Alzheimer , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Doença de Alzheimer/genética , Humanos , Estudo de Associação Genômica Ampla/métodos , Polimorfismo de Nucleotídeo Único , Heterogeneidade Genética
9.
J Zhejiang Univ Sci B ; 25(5): 361-388, 2024 May 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38725338

RESUMO

Ceria nanoparticles (CeO2 NPs) have become popular materials in biomedical and industrial fields due to their potential applications in anti-oxidation, cancer therapy, photocatalytic degradation of pollutants, sensors, etc. Many methods, including gas phase, solid phase, liquid phase, and the newly proposed green synthesis method, have been reported for the synthesis of CeO2 NPs. Due to the wide application of CeO2 NPs, concerns about their adverse impacts on human health have been raised. This review covers recent studies on the biomedical applications of CeO2 NPs, including their use in the treatment of various diseases (e.|g., Alzheimer's disease, ischemic stroke, retinal damage, chronic inflammation, and cancer). CeO2 NP toxicity is discussed in terms of the different systems of the human body (e.|g., cytotoxicity, genotoxicity, respiratory toxicity, neurotoxicity, and hepatotoxicity). This comprehensive review covers both fundamental discoveries and exploratory progress in CeO2 NP research that may lead to practical developments in the future.


Assuntos
Cério , Cério/química , Cério/toxicidade , Humanos , Animais , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Neoplasias/tratamento farmacológico , Doença de Alzheimer , Nanopartículas/toxicidade
10.
Sci Rep ; 14(1): 10755, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729989

RESUMO

Predicting the course of neurodegenerative disorders early has potential to greatly improve clinical management and patient outcomes. A key challenge for early prediction in real-world clinical settings is the lack of labeled data (i.e., clinical diagnosis). In contrast to supervised classification approaches that require labeled data, we propose an unsupervised multimodal trajectory modeling (MTM) approach based on a mixture of state space models that captures changes in longitudinal data (i.e., trajectories) and stratifies individuals without using clinical diagnosis for model training. MTM learns the relationship between states comprising expensive, invasive biomarkers (ß-amyloid, grey matter density) and readily obtainable cognitive observations. MTM training on trajectories stratifies individuals into clinically meaningful clusters more reliably than MTM training on baseline data alone and is robust to missing data (i.e., cognitive data alone or single assessments). Extracting an individualized cognitive health index (i.e., MTM-derived cluster membership index) allows us to predict progression to AD more precisely than standard clinical assessments (i.e., cognitive tests or MRI scans alone). Importantly, MTM generalizes successfully from research cohort to real-world clinical data from memory clinic patients with missing data, enhancing the clinical utility of our approach. Thus, our multimodal trajectory modeling approach provides a cost-effective and non-invasive tool for early dementia prediction without labeled data (i.e., clinical diagnosis) with strong potential for translation to clinical practice.


Assuntos
Encéfalo , Demência , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Demência/diagnóstico , Demência/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Idoso , Imageamento por Ressonância Magnética/métodos , Cognição/fisiologia , Progressão da Doença , Biomarcadores , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/metabolismo
11.
Sci Rep ; 14(1): 10728, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730027

RESUMO

The purpose of this study was to explore the diagnostic implications of ubiquitination-related gene signatures in Alzheimer's disease. In this study, we first collected 161 samples from the GEO database (including 87 in the AD group and 74 in the normal group). Subsequently, through differential expression analysis and the iUUCD 2.0 database, we obtained 3450 Differentially Expressed Genes (DEGs) and 806 Ubiquitin-related genes (UbRGs). After taking the intersection, we obtained 128 UbR-DEGs. Secondly, by conducting GO and KEGG enrichment analysis on these 128 UbR-DEGs, we identified the main molecular functions and biological pathways related to AD. Furthermore, through the utilization of GSEA analysis, we have gained insight into the enrichment of functions and pathways within both the AD and normal groups. Further, using lasso regression analysis and cross-validation techniques, we identified 22 characteristic genes associated with AD. Subsequently, we constructed a logistic regression model and optimized it, resulting in the identification of 6 RUbR-DEGs: KLHL21, WDR82, DTX3L, UBTD2, CISH, and ATXN3L. In addition, the ROC result showed that the diagnostic model we built has excellent accuracy and reliability in identifying AD patients. Finally, we constructed a lncRNA-miRNA-mRNA (competing endogenous RNA, ceRNA) regulatory network for AD based on six RUbR-DEGs, further elucidating the interaction between UbRGs and lncRNA, miRNA. In conclusion, our findings will contribute to further understanding of the molecular pathogenesis of AD and provide a new perspective for AD risk prediction, early diagnosis and targeted therapy in the population.


Assuntos
Doença de Alzheimer , Ubiquitinação , Doença de Alzheimer/genética , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Humanos , Perfilação da Expressão Gênica , Transcriptoma , Redes Reguladoras de Genes , Bases de Dados Genéticas
12.
BMC Psychiatry ; 24(1): 353, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730300

RESUMO

BACKGROUND: The seven tiered behavioural and psychological symptoms of dementia (BPSD) model of service delivery has been used by inpatient units. The classification of each tier is broadly defined and not always agreed upon by clinicians. The case study uses novel approach by combining the BPSD classification criteria with clinical presentation to identify the clinical characteristics of the case and match these characteristics against the BPSD classification. This process was enhanced by using case specific measures such as the Neuropsychiatric Inventory (NPI) and Cohen Mansfield Agitation Inventory (CMAI) scales and key clinical data. CASE PRESENTATION: A case study of 76 year old male diagnosed with mixed Alzheimer's and Vascular dementia. The clinical presentation of the symptomatology was deemed to be extreme, thus fitting into the seventh tier (Extreme) of the BPSD model of service delivery. The case is considered to fit into the Extreme BPSD category given the high levels of aggression, which were consistently reflected in high scores on NPI and CMAI, as well as long length of inpatient stay (over 3 years). The average number of Pro re nata (PRN) psychotropics medications per month was 56 and seclusion episodes of 6 times per month, with each episode lasting on average 132 min shows severity of behaviours. His level of aggression had resulted in environmental damage and staff injuries. CONCLUSION: We recommend patient clinical characteristics, relevant hospital data and specific measures should be used to develop consensus around defining and classifying cases into Extreme BPSD.


Assuntos
Agressão , Demência Vascular , Humanos , Masculino , Idoso , Agressão/psicologia , Demência Vascular/psicologia , Doença de Alzheimer/psicologia , Demência/psicologia , Sintomas Comportamentais/diagnóstico , Sintomas Comportamentais/psicologia , Sintomas Comportamentais/etiologia , Escalas de Graduação Psiquiátrica
13.
J Neuroinflammation ; 21(1): 125, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730470

RESUMO

BACKGROUND: Understanding the molecular mechanisms of Alzheimer's disease (AD) has important clinical implications for guiding therapy. Impaired amyloid beta (Aß) clearance is critical in the pathogenesis of sporadic AD, and blood monocytes play an important role in Aß clearance in the periphery. However, the mechanism underlying the defective phagocytosis of Aß by monocytes in AD remains unclear. METHODS: Initially, we collected whole blood samples from sporadic AD patients and isolated the monocytes for RNA sequencing analysis. By establishing APP/PS1 transgenic model mice with monocyte-specific cystatin F overexpression, we assessed the influence of monocyte-derived cystatin F on AD development. We further used a nondenaturing gel to identify the structure of the secreted cystatin F in plasma. Flow cytometry, enzyme-linked immunosorbent assays and laser scanning confocal microscopy were used to analyse the internalization of Aß by monocytes. Pull down assays, bimolecular fluorescence complementation assays and total internal reflection fluorescence microscopy were used to determine the interactions and potential interactional amino acids between the cystatin F protein and Aß. Finally, the cystatin F protein was purified and injected via the tail vein into 5XFAD mice to assess AD pathology. RESULTS: Our results demonstrated that the expression of the cystatin F protein was specifically increased in the monocytes of AD patients. Monocyte-derived cystatin F increased Aß deposition and exacerbated cognitive deficits in APP/PS1 mice. Furthermore, secreted cystatin F in the plasma of AD patients has a dimeric structure that is closely related to clinical signs of AD. Moreover, we noted that the cystatin F dimer blocks the phagocytosis of Aß by monocytes. Mechanistically, the cystatin F dimer physically interacts with Aß to inhibit its recognition and internalization by monocytes through certain amino acid interactions between the cystatin F dimer and Aß. We found that high levels of the cystatin F dimer protein in blood contributed to amyloid pathology and cognitive deficits as a risk factor in 5XFAD mice. CONCLUSIONS: Our findings highlight that the cystatin F dimer plays a crucial role in regulating Aß metabolism via its peripheral clearance pathway, providing us with a potential biomarker for diagnosis and potential target for therapeutic intervention.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Camundongos Transgênicos , Monócitos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Monócitos/metabolismo , Camundongos , Humanos , Peptídeos beta-Amiloides/metabolismo , Masculino , Feminino , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Idoso , Cistatinas/metabolismo , Cistatinas/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Idoso de 80 Anos ou mais , Camundongos Endogâmicos C57BL
14.
Alzheimers Res Ther ; 16(1): 106, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38730474

RESUMO

BACKGROUND: Previous studies on the associations between serum urate levels and neurodegenerative outcomes have yielded inconclusive results, and the causality remains unclear. This study aimed to investigate whether urate levels are associated with the risks of Alzheimer's disease and related dementias (ADRD), Parkinson's disease (PD), and neurodegenerative deaths. METHODS: This prospective study included 382,182 participants (45.7% men) from the UK Biobank cohort. Cox proportional hazards models were used to assess the associations between urate levels and risk of neurodegenerative outcomes. In the Mendelian randomization (MR) analysis, urate-related single-nucleotide polymorphisms were identified through a genome-wide association study. Both linear and non-linear MR approaches were utilized to investigate the potential causal associations. RESULTS: During a median follow-up period of 12 years, we documented 5,400 ADRD cases, 2,553 PD cases, and 1,531 neurodegenerative deaths. Observational data revealed that a higher urate level was associated with a decreased risk of ADRD (hazard ratio [HR]: 0.93, 95% confidence interval [CI]: 0.90, 0.96), PD (HR: 0.87, 95% CI: 0.82, 0.91), and neurodegenerative death (HR: 0.88, 95% CI: 0.83, 0.94). Negative linear associations between urate levels and neurodegenerative events were observed (all P-values for overall < 0.001 and all P-values for non-linearity > 0.05). However, MR analyses yielded no evidence of either linear or non-linear associations between genetically predicted urate levels and the risk of the aforementioned neurodegenerative events. CONCLUSION: Although the prospective cohort study demonstrated that elevated urate levels were associated with a reduced risk of neurodegenerative outcomes, MR analyses found no evidence of causality.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Ácido Úrico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Alzheimer/genética , Doença de Alzheimer/sangue , Doença de Alzheimer/epidemiologia , Estudos de Coortes , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/sangue , Doenças Neurodegenerativas/epidemiologia , Doença de Parkinson/genética , Doença de Parkinson/sangue , Doença de Parkinson/epidemiologia , Estudos Prospectivos , Biobanco do Reino Unido , Reino Unido/epidemiologia , Ácido Úrico/sangue
15.
Alzheimers Res Ther ; 16(1): 105, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730496

RESUMO

BACKGROUND: Alzheimer disease (AD) is a major health problem of aging, with tremendous burden on healthcare systems, patients, and families globally. Lecanemab, an FDA-approved amyloid beta (Aß)-directed antibody indicated for the treatment of early AD, binds with high affinity to soluble Aß protofibrils, which have been shown to be more toxic to neurons than monomers or insoluble fibrils. Lecanemab has been shown to be well tolerated in multiple clinical trials, although risks include an increased rate of amyloid-related imaging abnormalities (ARIA) and infusion reactions relative to placebo. METHODS: Clarity AD was an 18-month treatment (Core study), multicenter, double-blind, placebo-controlled, parallel-group study with open-label extension (OLE) in participants with early AD. Eligible participants were randomized 1:1 across 2 treatment groups (placebo and lecanemab 10 mg/kg biweekly). Safety evaluations included monitoring of vital signs, physical examinations, adverse events, clinical laboratory parameters, and 12-lead electrocardiograms. ARIA occurrence was monitored throughout the study by magnetic resonance imaging, read both locally and centrally. RESULTS: Overall, 1795 participants from Core and 1612 participants with at least one dose of lecanemab (Core + OLE) were included. Lecanemab was generally well-tolerated in Clarity AD, with no deaths related to lecanemab in the Core study. There were 9 deaths during the OLE, with 4 deemed possibly related to study treatment. Of the 24 deaths in Core + OLE, 3 were due to intracerebral hemorrhage (ICH): 1 placebo in the Core due to ICH, and 2 lecanemab in OLE with concurrent ICH (1 on tissue plasminogen activator and 1 on anticoagulant therapy). In the Core + OLE, the most common adverse events in the lecanemab group (> 10%) were infusion-related reactions (24.5%), ARIA with hemosiderin deposits (ARIA-H) microhemorrhages (16.0%), COVID-19 (14.7%), ARIA with edema (ARIA-E; 13.6%), and headache (10.3%). ARIA-E and ARIA-H were largely radiographically mild-to-moderate. ARIA-E generally occurred within 3-6 months of treatment, was more common in ApoE e4 carriers (16.8%) and most common in ApoE ε4 homozygous participants (34.5%). CONCLUSIONS: Lecanemab was generally well-tolerated, with the most common adverse events being infusion-related reactions, ARIA-H, ARIA-E. Clinicians, participants, and caregivers should understand the incidence, monitoring, and management of these events for optimal patient care. TRIAL REGISTRATION: ClinicalTrials.gov numbers: Clarity AD NCT03887455).


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Masculino , Método Duplo-Cego , Feminino , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Pessoa de Meia-Idade , Peptídeos beta-Amiloides/metabolismo , Imageamento por Ressonância Magnética , Resultado do Tratamento
16.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731800

RESUMO

Understanding the molecular underpinnings of neurodegeneration processes is a pressing challenge for medicine and neurobiology. Alzheimer's disease (AD) and Parkinson's disease (PD) represent the most prevalent forms of neurodegeneration. To date, a substantial body of experimental evidence has strongly implicated hypoxia in the pathogenesis of numerous neurological disorders, including AD, PD, and other age-related neurodegenerative conditions. Hypoxia-inducible factor (HIF) is a transcription factor that triggers a cell survival program in conditions of oxygen deprivation. The involvement of HIF-1α in neurodegenerative processes presents a complex and sometimes contradictory picture. This review aims to elucidate the current understanding of the interplay between hypoxia and the development of AD and PD, assess the involvement of HIF-1 in their pathogenesis, and summarize promising therapeutic approaches centered on modulating the activity of the HIF-1 complex.


Assuntos
Homeostase , Subunidade alfa do Fator 1 Induzível por Hipóxia , Doenças Neurodegenerativas , Oxigênio , Doença de Parkinson , Humanos , Oxigênio/metabolismo , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/etiologia , Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo
17.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731812

RESUMO

We compared the clinical and analytical performance of Alzheimer's disease (AD) plasma biomarkers measured using the single-molecule array (Simoa) and Lumipulse platforms. We quantified the plasma levels of amyloid beta 42 (Aß42), Aß40, phosphorylated tau (Ptau181), and total tau biomarkers in 81 patients with mild cognitive impairment (MCI), 30 with AD, and 16 with non-AD dementia. We found a strong correlation between the Simoa and Lumipulse methods. Concerning the clinical diagnosis, Simoa Ptau181/Aß42 (AUC 0.739, 95% CI 0.592-0.887) and Lumipulse Aß42 and Ptau181/Aß42 (AUC 0.735, 95% CI 0.589-0.882 and AUC 0.733, 95% CI 0.567-0.900) had the highest discriminating power. However, their power was significantly lower than that of CSF Aß42/Aß40, as measured by Lumipulse (AUC 0.879, 95% CI 0.766-0.992). Simoa Ptau181 and Lumipulse Ptau181/Aß42 were the markers most consistent with the CSF Aß42/Aß40 status (AUC 0.801, 95% CI 0.712-0.890 vs. AUC 0.870, 95% CI 0.806-0.934, respectively) at the ≥2.127 and ≥0.084 cut-offs, respectively. The performance of the Simoa and Lumipulse plasma AD assays is weaker than that of CSF AD biomarkers. At present, the analysed AD plasma biomarkers may be useful for screening to reduce the number of lumbar punctures in the clinical setting.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Disfunção Cognitiva , Proteínas tau , Humanos , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Masculino , Feminino , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/sangue , Idoso , Proteínas tau/líquido cefalorraquidiano , Proteínas tau/sangue , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/sangue , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fragmentos de Peptídeos/sangue , Idoso de 80 Anos ou mais , Fosforilação
18.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731839

RESUMO

CLEC4G, a glycan-binding receptor, has previously been demonstrated to inhibit Aß generation, yet its brain localization and functions in Alzheimer's disease (AD) are not clear. We explored the localization, function, and regulatory network of CLEC4G via experiments and analysis of RNA-seq databases. CLEC4G transcripts and proteins were identified in brain tissues, with the highest expression observed in neurons. Notably, AD was associated with reduced levels of CLEC4G transcripts. Bioinformatic analyses revealed interactions between CLEC4G and relevant genes such as BACE1, NPC1, PILRA, TYROBP, MGAT1, and MGAT3, all displaying a negative correlation trend. We further identified the upstream transcriptional regulators NR2F6 and XRCC4 for CLEC4G and confirmed a decrease in CLEC4G expression in APP/PS1 transgenic mice. This study highlights the role of CLEC4G in protecting against AD progression and the significance of CLEC4G for AD research and management.


Assuntos
Doença de Alzheimer , Lectinas Tipo C , Camundongos Transgênicos , Neurônios , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Neurônios/metabolismo , Camundongos , Humanos , Lectinas Tipo C/metabolismo , Lectinas Tipo C/genética , Encéfalo/metabolismo , Encéfalo/patologia , Regulação da Expressão Gênica , Modelos Animais de Doenças
19.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731856

RESUMO

We characterized the therapeutic biological modes of action of several terpenes in Poria cocos F.A Wolf (PC) and proposed a broad therapeutic mode of action for PC. Molecular docking and drug-induced transcriptome analysis were performed to confirm the pharmacological mechanism of PC terpene, and a new analysis method, namely diffusion network analysis, was proposed to verify the mechanism of action against Alzheimer's disease. We confirmed that the compound that exists only in PC has a unique mechanism through statistical-based docking analysis. Also, docking and transcriptomic analysis results could reflect results in clinical practice when used complementarily. The detailed pharmacological mechanism of PC was confirmed by constructing and analyzing the Alzheimer's disease diffusion network, and the antioxidant activity based on microglial cells was verified. In this study, we used two bioinformatics approaches to reveal PC's broad mode of action while also using diffusion networks to identify its detailed pharmacological mechanisms of action. The results of this study provide evidence that future pharmacological mechanism analysis should simultaneously consider complementary docking and transcriptomics and suggest diffusion network analysis, a new method to derive pharmacological mechanisms based on natural complex compounds.


Assuntos
Simulação de Acoplamento Molecular , Terpenos , Transcriptoma , Terpenos/farmacologia , Terpenos/química , Transcriptoma/efeitos dos fármacos , Humanos , Wolfiporia/química , Perfilação da Expressão Gênica/métodos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Microglia/efeitos dos fármacos , Microglia/metabolismo , Antioxidantes/farmacologia , Antioxidantes/química , Biologia Computacional/métodos , Animais
20.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731858

RESUMO

This editorial investigates chronic traumatic encephalopathy (CTE) as a course of Alzheimer's disease (AD). CTE is a debilitating neurodegenerative disease that is the result of repeated mild traumatic brain injury (TBI). Many epidemiological studies show that experiencing a TBI in early or middle life is associated with an increased risk of dementia later in life. Chronic traumatic encephalopathy (CTE) and Alzheimer's disease (AD) present a series of similar neuropathological features that were investigated in this work like recombinant tau into filaments or the accumulation and aggregation of Aß protein. However, these two conditions differ from each other in brain-blood barrier damage. The purpose of this review was to evaluate information about CTE and AD from various articles, focusing especially on new therapeutic possibilities for the improvement in cognitive skills.


Assuntos
Doença de Alzheimer , Encefalopatia Traumática Crônica , Humanos , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Doença de Alzheimer/etiologia , Encefalopatia Traumática Crônica/patologia , Encefalopatia Traumática Crônica/complicações , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia
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