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1.
Biomaterials ; 312: 122749, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39121725

RESUMO

The prevalence of Alzheimer's disease (AD) is increasing globally due to population aging. However, effective clinical treatment strategies for AD still remain elusive. The mechanisms underlying AD onset and the interplay between its pathological factors have so far been unclear. Evidence indicates that AD progression is ultimately driven by neuronal loss, which in turn is caused by neuroapoptosis and neuroinflammation. Therefore, the inhibition of neuroapoptosis and neuroinflammation could be a useful anti-AD strategy. Nonetheless, the delivery of active drug agents into the brain parenchyma is hindered by the blood-brain barrier (BBB). To address this challenge, we fabricated a black phosphorus nanosheet (BP)-based methylene blue (MB) delivery system (BP-MB) for AD therapy. After confirming the successful preparation of BP-MB, we proved that its BBB-crossing ability was enhanced under near-infrared light irradiation. In vitro pharmacodynamics analysis revealed that BP and MB could synergistically scavenge excessive reactive oxygen species (ROS) in okadaic acid (OA)-treated PC12 cells and lipopolysaccharide (LPS)-treated BV2 cells, thus efficiently reversing neuroapoptosis and neuroinflammation. To study in vivo pharmacodynamics, we established a mouse model of AD mice, and behavioral tests confirmed that BP-MB treatment could successfully improve cognitive function in these animals. Notably, the results of pathological evaluation were consistent with those of the in vitro assays. The findings demonstrated that BP-MB could scavenge excessive ROS and inhibit Tau hyperphosphorylation, thereby alleviating downstream neuroapoptosis and regulating the polarization of microglia from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. Overall, this study highlights the therapeutic potential of a smart nanomedicine with the capability of reversing neuroapoptosis and neuroinflammation for AD treatment.


Assuntos
Doença de Alzheimer , Apoptose , Barreira Hematoencefálica , Azul de Metileno , Nanomedicina , Doenças Neuroinflamatórias , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Apoptose/efeitos dos fármacos , Células PC12 , Doenças Neuroinflamatórias/tratamento farmacológico , Ratos , Camundongos , Nanomedicina/métodos , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Masculino , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos C57BL
2.
Alzheimers Res Ther ; 16(1): 196, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232823

RESUMO

BACKGROUND: While several studies in cerebral amyloid angiopathy (CAA) focus on cognitive function, data on neuropsychiatric symptoms (NPS) and lifelong mental activities in these patients are scarce. Since NPS are associated with functional impairment, faster cognitive decline and faster progression to death, replication studies in more diverse settings and samples are warranted. METHODS: We prospectively recruited n = 69 CAA patients and n = 18 cognitively normal controls (NC). The number and severity of NPS were assessed using the Alzheimer's Disease (AD) Assessment Scale's (ADAS) noncognitive subscale. We applied different regression models exploring associations between NPS number or severity and group status (CAA vs. NC), CAA severity assessed with magnetic resonance imaging (MRI) or cognitive function (Mini-Mental State Examination (MMSE), ADAS cognitive subscale), adjusting for age, sex, years of education, arterial hypertension, AD pathology, and apolipoprotein E status. Mediation analyses were performed to test indirect effects of lifelong mental activities on CAA severity and NPS. RESULTS: Patients with CAA had 4.86 times (95% CI 2.20-10.73) more NPS and 3.56 units (95% CI 1.94-5.19) higher expected NPS severity than NC. Higher total CAA severity on MRI predicted 1.14 times (95% CI 1.01.-1.27) more NPS and 0.57 units (95% CI 0.19-0.95) higher expected NPS severity. More severe white matter hyperintensities were associated with 1.21 times more NPS (95% CI 1.05-1.39) and 0.63 units (95% CI 0.19-1.08) more severe NPS. NPS number (MMSE mean difference - 1.15, 95% CI -1.67 to -0.63; ADAS cognitive mean difference 1.91, 95% CI 1.26-2.56) and severity (MMSE - 0.55, 95% CI -0.80 to -0.30; ADAS cognitive mean difference 0.89, 95% CI 0.57-1.21) predicted lower cognitive function. Greater lifelong mental activities partially mediated the relationship between CAA severity and NPS (indirect effect 0.05, 95% CI 0.0007-0.13), and greater lifelong mental activities led to less pronounced CAA severity and thus to less NPS (indirect effect - 0.08, 95% CI -0.22 to -0.002). DISCUSSION: This study suggests that NPS are common in CAA, and that this relationship may be driven by CAA severity. Furthermore, NPS seem to be tied to lower cognitive function. However, lifelong mental activities might mitigate the impact of NPS in CAA.


Assuntos
Angiopatia Amiloide Cerebral , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Humanos , Feminino , Masculino , Idoso , Estudos Transversais , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Angiopatia Amiloide Cerebral/psicologia , Pessoa de Meia-Idade , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Estudos Prospectivos , Índice de Gravidade de Doença , Idoso de 80 Anos ou mais
3.
Transl Neurodegener ; 13(1): 45, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232848

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder, characterized pathologically by extracellular deposition of ß-amyloid (Aß) into senile plaques and intracellular accumulation of hyperphosphorylated tau (pTau) as neurofibrillary tangles. Clinically, AD patients show memory deterioration with varying cognitive dysfunctions. The exact molecular mechanisms underlying AD are still not fully understood, and there are no efficient drugs to stop or reverse the disease progression. In this review, we first provide an update on how the risk factors, including APOE variants, infections and inflammation, contribute to AD; how Aß and tau become abnormally accumulated and how this accumulation plays a role in AD neurodegeneration. Then we summarize the commonly used experimental models, diagnostic and prediction strategies, and advances in periphery biomarkers from high-risk populations for AD. Finally, we introduce current status of development of disease-modifying drugs, including the newly officially approved Aß vaccines, as well as novel and promising strategies to target the abnormal pTau. Together, this paper was aimed to update AD research progress from fundamental mechanisms to the clinical diagnosis and therapies.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/terapia , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Humanos , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Biomarcadores/metabolismo , Biomarcadores/análise
4.
Front Neurol ; 15: 1425495, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39233680

RESUMO

Background: South Carolina has arguably the most robust Alzheimer's Registry in the United States. For enhanced planning in both clinical practice and research and better utilization of the Registry data, it is important to understand survival after Registry entry. To this end, we conducted exploratory analyses to examine the patterns of longevity/survival in the South Carolina Alzheimer's Disease Registry. Methods: The sample included 42,028 individuals in the South Carolina Alzheimer's Disease Registry (SCADR). Participants were grouped into four cohorts based on their year of diagnosis. Longevity in the Registry (LIR), or the length of survival in the registry, was calculated based on the years of reported diagnosis and death. Results: The median LIR varied between 24 to 36 months depending on the cohort, with 75% of individuals in the three recent cohorts surviving for at least 12 months. Across all cohorts, 25% of the participants survived at least 60 months. The median LIR of females was longer than that of males. Individuals whose race was classified as Asian, American Indian, and other than listed had longer LIR compared to White, African American, and Hispanic individuals. Median LIR was shorter for Registry cases diagnosed at an earlier age (less than 65 years). Conclusion: Our data indicate that significant longevity is to be expected in the SCADR but that there is interesting variability which needs to be explored in subsequent studies. The SCADR is a rich data source prime for use in research studies and analyses.

5.
Patterns (N Y) ; 5(8): 101031, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39233693

RESUMO

The amount of biomedical data continues to grow rapidly. However, collecting data from multiple sites for joint analysis remains challenging due to security, privacy, and regulatory concerns. To overcome this challenge, we use federated learning, which enables distributed training of neural network models over multiple data sources without sharing data. Each site trains the neural network over its private data for some time and then shares the neural network parameters (i.e., weights and/or gradients) with a federation controller, which in turn aggregates the local models and sends the resulting community model back to each site, and the process repeats. Our federated learning architecture, MetisFL, provides strong security and privacy. First, sample data never leave a site. Second, neural network parameters are encrypted before transmission and the global neural model is computed under fully homomorphic encryption. Finally, we use information-theoretic methods to limit information leakage from the neural model to prevent a "curious" site from performing model inversion or membership attacks. We present a thorough evaluation of the performance of secure, private federated learning in neuroimaging tasks, including for predicting Alzheimer's disease and for brain age gap estimation (BrainAGE) from magnetic resonance imaging (MRI) studies in challenging, heterogeneous federated environments where sites have different amounts of data and statistical distributions.

6.
Front Aging Neurosci ; 16: 1444716, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39233828

RESUMO

Introduction: Alzheimer's disease (AD), a major cause of dementia globally, imposes significant societal and personal costs. This review explores the efficacy of physical exercise as a non-pharmacological intervention to mitigate the impacts of AD. Methods: This review draws on recent studies that investigate the effects of physical exercise on neuroinflammation and neuronal enhancement in individuals with AD. Results: Consistent physical exercise alters neuroinflammatory pathways, enhances cognitive functions, and bolsters brain health among AD patients. It favorably influences the activation states of microglia and astrocytes, fortifies the integrity of the blood-brain barrier, and attenuates gut inflammation associated with AD. These changes are associated with substantial improvements in cognitive performance and brain health indicators. Discussion: The findings underscore the potential of integrating physical exercise into comprehensive AD management strategies. Emphasizing the necessity for further research, this review advocates for the refinement of exercise regimens to maximize their enduring benefits in decelerating the progression of AD.

7.
Behav Neurol ; 2024: 5698119, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39233848

RESUMO

Objective: The objective of the study is to investigate whether quercetin ameliorates Alzheimer's disease (AD)-like pathology in APP/PS1 double transgenic mice and its hypothesized mechanism, contributing to the comprehension of AD pathogenesis. Methods: A total of 30 APP/PS1 transgenic mice were randomized into model group (APP/PS1), quercetin group (APP/PS1+Q), and donepezil hydrochloride group (APP/PS1+DON). Simultaneously, there were 10 C57 mice of the same age served as a control group. Three months posttreatment, the effects of quercetin on AD mice were evaluated using the Morris water maze (MWM) test, Y maze experiment, immunohistochemistry, immunofluorescence, and western blotting. Results: Results from the water maze and Y maze indicated that quercetin significantly improved cognitive impairment in APP/PS1 transgenic AD mice. Additionally, serum enzyme-linked immunosorbent assay (ELISA) results demonstrated that quercetin elevated MDA, superoxide dismutase (SOD), CAT, GSH, acetylcholine (ACh), and acetylcholinesterase (AChE) levels in AD mice. Hematoxylin-eosin (HE) staining, Nissl staining, and hippocampal tissue thioflavine staining revealed that quercetin reduced neuronal damage and Aß protein accumulation in AD mice. Western blot validated protein expression in the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2)/HO-1 pathway associated with oxidative stress and apoptosis, confirming quercetin's potential molecular mechanism of enhancing AD mouse cognition. Furthermore, western blot findings indicate that quercetin significantly alters protein expression in the Keap1/Nrf2/HO-1 pathway. Moreover, molecular docking analysis suggests that Keap1, NQO1, HO-1, caspase-3, Bcl-2, and Bax proteins in the Keap1/Nrf2/HO-1 pathway may be potential regulatory targets of quercetin. These findings will provide a molecular basis for quercetin's clinical application in AD treatment. Conclusion: Quercetin can improve cognitive impairment and AD-like pathology in APP/PS1 double transgenic mice, potentially related to quercetin's activation of the Keap1/Nrf2/HO-1 pathway and reduction of cell apoptosis.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Apoptose , Encéfalo , Disfunção Cognitiva , Modelos Animais de Doenças , Heme Oxigenase-1 , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Quercetina , Animais , Quercetina/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Camundongos , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Heme Oxigenase-1/metabolismo , Apoptose/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Transdução de Sinais/efeitos dos fármacos , Presenilina-1/genética , Presenilina-1/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Antioxidantes/farmacologia , Antioxidantes/metabolismo
8.
Front Pharmacol ; 15: 1440515, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39234102

RESUMO

Background: Senescence-accelerated mouse prone 8 (SAMP8) and age-matched SAMR1 mice are used to study the pathogenesis and therapeutics of Alzheimer's disease (AD); however, the molecular mechanisms are not completely understood. Objective: This study aimed to examine the effects of the 5-month administration of formononetin in SAMP8 mice and used RNA-seq to explore the molecular targets. Methods: SAMP8 mice were orally administered formononetin (0, 8, and 16 mg/kg) from 4 months of age, and age-matched SAMR1 mice were used as controls. Behavioral tests were performed in 9-month-old mice, followed by histopathologic analysis. Total RNA from the hippocampus was isolated and subjected to RNA-seq, RT-qPCR, and bioinformatics analysis. Results: The 9-month-old SAMP8 mice exhibited cognition deficits, evidenced by novel object recognition, open-field test, elevated plus maze, and passive avoidance. Nissl bodies in the cortex and hippocampus were decreased. Formononetin treatments ameliorated behavioral deficits and improved morphological changes, which were evidenced by Nissl and H&E staining. RNA-seq revealed distinct gene expression patterns between SAMP8 and SAMR1 mice. Differentially expressed genes in SAMP8 mice were attenuated or normalized by formononetin. Ingenuity pathway analysis (IPA) of canonical pathway and upstream regulators revealed increases in proinflammatory factors and immune dysfunction and decreases in NRF2 and SIRT-1 signaling pathways, leading to neuroinflammation. Formononetin treatment attenuated or reversed these molecular changes. The transcriptome of SAMP8 mice was correlated with transcriptomic profiles of other AD mouse models in the GEO database. Conclusion: Neuroinflammation and decreased antioxidant and SIRT-1 signaling contributed to cognitive deficits in aged SAMP8 mice, which are potential therapeutic targets of formononetin in combination with other therapies.

9.
Front Hum Neurosci ; 18: 1424920, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39234407

RESUMO

Past studies have explored formant centering, a corrective behavior of convergence over the duration of an utterance toward the formants of a putative target vowel. In this study, we establish the existence of a similar centering phenomenon for pitch in healthy elderly controls and examine how such corrective behavior is altered in Alzheimer's Disease (AD). We found the pitch centering response in healthy elderly was similar when correcting pitch errors below and above the target (median) pitch. In contrast, patients with AD showed an asymmetry with a larger correction for the pitch errors below the target phonation than above the target phonation. These findings indicate that pitch centering is a robust compensation behavior in human speech. Our findings also explore the potential impacts on pitch centering from neurodegenerative processes impacting speech in AD.

10.
Curr Neuropharmacol ; 22(12): 1942-1959, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39234772

RESUMO

Alzheimer's disease (AD) is a severe progressive neurodegenerative condition associated with neuronal damage and reduced cognitive function that primarily affects the aged worldwide. While there is increasing evidence suggesting that mitochondrial dysfunction is one of the most significant factors contributing to AD, its accurate pathobiology remains unclear. Mitochondrial bioenergetics and homeostasis are impaired and defected during AD pathogenesis. However, the potential of mutations in nuclear or mitochondrial DNA encoding mitochondrial constituents to cause mitochondrial dysfunction has been considered since it is one of the intracellular processes commonly compromised in early AD stages. Additionally, electron transport chain dysfunction and mitochondrial pathological protein interactions are related to mitochondrial dysfunction in AD. Many mitochondrial parameters decline during aging, causing an imbalance in reactive oxygen species (ROS) production, leading to oxidative stress in age-related AD. Moreover, neuroinflammation is another potential causative factor in AD-associated mitochondrial dysfunction. While several treatments targeting mitochondrial dysfunction have undergone preclinical studies, few have been successful in clinical trials. Therefore, this review discusses the molecular mechanisms and different therapeutic approaches for correcting mitochondrial dysfunction in AD, which have the potential to advance the future development of novel drug-based AD interventions.


Assuntos
Doença de Alzheimer , Mitocôndrias , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Doenças Mitocondriais/tratamento farmacológico , Doenças Mitocondriais/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
Brain Commun ; 6(5): fcae277, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39239152

RESUMO

Compelling evidence suggests that cognitive decline in Alzheimer's disease is associated with the accumulation and aggregation of tau protein, with the most toxic aggregates being in the form of oligomers. This underscores the necessity for direct isolation and analysis of brain-derived tau oligomers from patients with Alzheimer's disease, potentially offering novel perspectives into tau toxicity. Alzheimer's brain-derived tau oligomers are potent inhibitors of synaptic plasticity; however, the involved mechanism is still not fully understood. We previously reported a significantly reduced incidence of Alzheimer's disease in ageing humans chronically treated with a Food and Drug Administration-approved calcineurin inhibitor, FK506 (tacrolimus), used as an immunosuppressant after solid organ transplant. Using a combination of electrophysiological and RNA-sequencing techniques, we provide here evidence that FK506 has the potential to block the acute toxic effect of brain-derived tau oligomers on synaptic plasticity, as well as to restore the levels of some key synaptic mRNAs. These results further support FK506 as a promising novel therapeutic strategy for the treatment of Alzheimer's disease.

12.
Ageing Res Rev ; 101: 102476, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39222668

RESUMO

Alzheimer's disease (AD) is a significant neocortical degenerative disorder characterized by the progressive loss of neurons and secondary alterations in white matter tracts. Understanding the risk factors and mechanisms underlying AD is crucial for developing effective treatments. The risk factors associated with AD encompass a wide range of variables, including gender differences, family history, and genetic predispositions. Additionally, environmental factors such as air pollution and lifestyle-related conditions like cardiovascular disease, gut pathogens, and liver pathology contribute substantially to the development and progression of AD and its subtypes. This review provides current update and deeper insights into the role of diverse risk factors, categorizing AD into its distinct subtypes and elucidating their specific pathophysiological mechanisms. Unlike previous studies that often focus on isolated aspects of AD, our review integrates these factors to offer a comprehensive understanding of the disease. Furthermore, the review explores a variety of drug targets linked to the neuropathology of different AD subtypes, highlighting the potential for targeted therapeutic interventions. We further discussed the novel therapeutic options and categorized them according to their targets. The roles of different drug targets were comprehensively studied, and the mechanism of action of their inhibitors was discussed in detail. By comprehensively covering the interplay of risk factors, subtype differentiation, and drug targets, this review provides a deeper understanding of AD and suggests directions for future research and therapeutic strategies.

13.
Ageing Res Rev ; 101: 102480, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39236857

RESUMO

Mitochondria functionally degrade as neurons age. Degenerative changes cause inefficient oxidative phosphorylation (OXPHOS) and elevated electron leakage from the electron transport chain (ETC) promoting increased intramitochondrial generation of damaging reactive oxygen and reactive nitrogen species (ROS and RNS). The associated progressive accumulation of molecular damage causes an increasingly rapid decline in mitochondrial physiology contributing to aging. Melatonin, a multifunctional free radical scavenger and indirect antioxidant, is synthesized in the mitochondrial matrix of neurons. Melatonin reduces electron leakage from the ETC and elevates ATP production; it also detoxifies ROS/RNS and via the SIRT3/FOXO pathway it upregulates activities of superoxide dismutase 2 and glutathione peroxidase. Melatonin also influences glucose processing by neurons. In neurogenerative diseases, neurons often adopt Warburg-type metabolism which excludes pyruvate from the mitochondria causing reduced intramitochondrial acetyl coenzyme A production. Acetyl coenzyme A supports the citric acid cycle and OXPHOS. Additionally, acetyl coenzyme A is a required co-substrate for arylalkylamine-N-acetyl transferase, which rate limits melatonin synthesis; therefore, melatonin production is diminished in cells that experience Warburg-type metabolism making mitochondria more vulnerable to oxidative stress. Moreover, endogenously produced melatonin diminishes during aging, further increasing oxidative damage to mitochondrial components. More normal mitochondrial physiology is preserved in aging neurons with melatonin supplementation.

14.
J Trace Elem Med Biol ; 86: 127515, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39241488

RESUMO

Studies on essential trace elements in the context of Alzheimer's disease (AD) concluded that Cu, Fe and Zn interact with amyloid-ß, accelerating plaque formation in the brain. Additionally, Cu and Fe in the vicinity of plaques produce reactive oxygen species (ROS) resulting in oxidative stress, whereas Zn plays a role in the antioxidant defence as a co-factor for antioxidants. In this work, the Cu, Fe and Zn concentrations and isotope ratios were determined in whole blood, blood serum and cerebrospinal fluid of 10 patients diagnosed with AD and 8 control individuals, using tandem (ICP-MS/MS) and multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), respectively. In whole blood and blood serum of AD patients, a heavier Cu isotopic composition was observed (significant for whole blood only) compared to controls. Albumin levels in cerebrospinal fluid tend to increase with age, which could indicate an increased leakiness of the blood-brain barrier. In cerebrospinal fluid, a large variability was observed for the Cu and Fe isotope ratios, potentially resulting from that leakiness at the blood-brain barrier. Therefore, potential effects of AD on the concentration and isotopic composition of essential elements in cerebrospinal fluid related to amyloid-ß formation could be hidden. Finally, in blood serum, Zn, urea and creatinine concentrations showed an increase with age and showed a significant difference between sexes.

15.
Parkinsonism Relat Disord ; 128: 107125, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39241508

RESUMO

INTRODUCTION: Neurodegenerative diseases (NDDs) result from a complex interplay of genetic, environmental and aging factors. A balanced diet and adequate physical activity (PA) are recognized as pivotal components among modifiable environmental factors. The independent impact on NDD incidence has been previously debated. This investigation seeks to delineate the association between PA and NDDs across various levels of adherence to a plant-based diet. METHODS: In this study, a cohort of 368,934 participants from the UK Biobank was analyzed. Total physical activity (TPA) levels and healthful plant-based diet index (hPDI) were calculated and categorized. A multiple adjusted Cox model was utilized to evaluate the influence of TPA and hPDI on common NDDs, respectively. RESULTS: Finally, 4602 identified cases diagnosed as Alzheimer's disease (AD), Parkinson's disease (PD) or amyotrophic lateral sclerosis (ALS). We found that higher TPA was significantly associated with a reduced risk of developing AD (Q3: HR 0.87; Q4: HR 0.78) and PD (Q3: HR 0.86; Q4: HR 0.81). The protective effect was further accentuated with adherence to a plant-based diet. However, these connections were not observed in the analysis of ALS regardless of dietary patterns. CONCLUSION: Our findings underscore a significant association between higher TPA and reduced risks of AD and PD, with an enhanced effect observed in conjunction with a plant-based diet. This study contributes to addressing the knowledge gap regarding the combined impact of TPA and a plant-based diet on NDDs occurrence, providing insights into potential underlying mechanisms.

16.
Neurobiol Aging ; 144: 12-18, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39241563

RESUMO

The amyloid beta (Aß) 42/40 ratio has been widely studied as a biomarker in Alzheimer's disease (AD); however, other Aß peptides could also represent relevant biomarkers. We measured levels of Aß38/40/42 in plasma samples from cognitively-unimpaired older adults and determined the relationships between Aß levels and amyloid positron-emission-tomography (PET) and performance on a learning and memory task. We found that all Aß peptides individually and the Aß42/40 ratio, but not the Aß42/38 ratio, were significantly correlated with brain amyloid (Aß-PET). Multiple linear modeling, adjusting for age, sex, education, APOE4 and Aß-PET showed significant associations between the Aß42/38 ratio and memory. Further, associations between the Aß42/38 ratio and learning scores were stronger in males and in Aß-PET-negative individuals. In contrast, no significant associations were detected between the Aß42/40 ratio and any learning measure. These studies implicate the Aß42/38 ratio as a biomarker to assess early memory deficits and underscore the utility of the Aß38 fragment as an important biomarker in the AD field.

17.
Asian J Psychiatr ; 101: 104204, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39241656

RESUMO

BACKGROUND: The number of patients with Alzheimer's disease (AD) has increased dramatically in Asia. OBJECTIVE: To update the demographic characteristics of patients with AD and their informants in eight Asian countries and compare them from 12 years prior. METHODS: The A1-A3 components of the Uniform Dataset (UDS), version 3.0, were administered in Taiwan, Beijing, Hong Kong, Korea, Japan, Philippines, Thailand, and Indonesia. Data were compared with patients with AD in the first registration using the UDS version 1.0 from 2010-2014 in the same regions. RESULTS: A total of 1885 patients with AD and their informants were recruited from 2022 to 2024 and were compared with 2042 patients recruited a decade prior. Each country had its own unique characteristics that changed between both eras. The mean age of the patients and informants was 79.8±8.2 years and 56.5±12.1 years, respectively. Compared with the first registration, the patients were older (79.8 vs 79.0, p=0.002) and had worse global function (mean CDR-SB scores 6.1 vs 5.8, p<0.001); more informants were children (56 % vs. 48 %, p<0.001), and their frequency of in-person visits increased significantly if not living together. A total of 11 %, 4.5 %, 11 %, and 0.4 % of the patients had a reported history of cognitive impairment in their mothers, fathers, siblings, and children, respectively; all percentages, except children, increased significantly over the past decade. CONCLUSION: The present study reports the heterogeneous characteristics of patients with AD and their informants in Asian countries, and the distinct changes in the past decade. The differences in dementia evaluation and care between developing and developed countries warrant further investigation.

18.
J Am Geriatr Soc ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242359

RESUMO

BACKGROUND: Antipsychotic and other psychotropic medication use is prevalent among community-dwelling older adults with dementia despite the potential for adverse effects. Two Centers for Medicare & Medicaid Services (CMS) initiatives, the National Partnership to Improve Dementia Care ("the Partnership") and the Five Star Quality Rating System for antipsychotic use reporting, have been successful in reducing antipsychotic use in nursing home residents. We assessed if these initiatives had a spillover effect in antipsychotic and other psychotropic medication use among community dwellers with dementia due to potential overlap in prescribers across settings. METHODS: Among community-dwelling older adults with dementia, we examined psychotropic medication class use (i.e., antipsychotics, antidepressants, anxiolytics, anticonvulsants/mood stabilizers, antidementia) in 2010-2017 Medicare fee-for-service claims using interrupted time series analyses across three periods ("Pre-Partnership": July 1, 2010 to March 31, 2012; "Post-Partnership": April 1, 2012 to January 31, 2015; "Five Star Quality Rating": February 1, 2015 to December 31, 2017). RESULTS: We included 1,289,401 community dwellers with dementia contributing 26,609,697 person-months. The mean age was 80 years, most were female (70%), approximately 80% were non-Hispanic Whites, 10% were non-Hispanic Blacks, and 5% were Hispanic ethnicity. Antipsychotic use was declining pre-Partnership (ß = -0.06, 95% CI: -0.08, -0.05) and post-Partnership (ß = -0.02, 95% CI: -0.02, -0.01). Post-Five Star Quality Rating, antipsychotic use remained stable with a nearly flat slope (ß = -0.01, 95% CI: -0.01, 0.00). Anticonvulsant and antidepressant use increased and anxiolytic and antidementia medication use decreased among community-dwelling older adults with dementia. CONCLUSIONS: These two CMS policies on antipsychotic use for nursing home residents were not associated with a spillover effect to community-dwelling older adults with dementia. Strategies to monitor the appropriateness of psychotropic medication use may be warranted for community-dwellers with dementia.

19.
J Leukoc Biol ; 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39243388

RESUMO

Dysfunctional phagocytic clearance of ß-amyloid (Aß) in microglia and peripheral macrophages/monocytes has been implicated in Alzheimer's disease (AD), but the mechanisms underlying this dysfunction are not yet well understood. In this study, we examined the role of glia maturation factor-γ (GMFG), an actin-disassembly protein that is highly expressed in immune cells, in macrophage Aß phagocytosis and in regulating scavenger receptor AI (SR-AI), a cell-surface receptor that has previously been implicated in Aß clearance. GMFG knockdown increased phagocytosis of Aß42 in BMDMs and RAW264.7 murine macrophages, while GMFG overexpression reduced Aß42 uptake in these cells. Blocking with anti-SR-AI antibodies inhibited Aß42 uptake in GMFG-knockdown cells, establishing a role for SR-AI in Aß42 phagocytosis. GMFG knockdown increased SR-AI protein expression under both basal conditions and in response to Aß42 treatment via both the transcriptional and post-transcriptional level in RAW264.7 macrophages. GMFG knockdown modulated Aß42-induced K48-linked and K63-polyubiquitination of SR-AI, the phosphorylation of SR-AI and JNK, suggesting that GMFG plays a role for intracellular signaling in the SR-AI-mediated uptake of Aß. Further, GMFG-knockdown cells displayed increased levels of the transcriptional factor MafB, and silencing of MafB in these cells reduced their SR-AI expression. Finally, GMFG was found to interact with the nuclear pore complex component RanBP2, and silencing of RanBP2 in GMFG-knockdown cells reduced their SR-AI expression. Collectively, these data support the role of GMFG as a novel regulator of SR-AI in macrophage Aß phagocytosis, and may provide insight into therapeutic approaches to potentially slow or prevent the progression of AD.

20.
Eur J Med Chem ; 279: 116810, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39243456

RESUMO

Alzheimer's disease (AD) is the most common form of dementia among the elderly, accounting for 60 %-70 % of cases. At present, the pathogenesis of this condition remains unclear, but the hydrolysis of acetylcholine (ACh) is thought to play a role. Acetylcholinesterase (AChE) can break down ACh transmission from the presynaptic membrane and stop neurotransmitters' excitatory effect on the postsynaptic membrane, which plays a key role in nerve conduction. Acetylcholinesterase inhibitors (AChEIs) can delay the hydrolysis of acetylcholine (ACh), which represents a key strategy for treating AD. Due to its complex etiology, AD has proven challenging to treat. Various inhibitors and antagonists targeting key enzymes and proteins implicated in the disease's pathogenesis have been explored as potential therapeutic agents. These include Glycogen Synthase Kinase 3ß (GSK-3ß) inhibitors, ß-site APP Cleaving Enzyme (BACE-1) inhibitors, Monoamine Oxidase (MAO) inhibitors, Phosphodiesterase inhibitors (PDEs), N-methyl--aspartic Acid (NMDA) antagonists, Histamine 3 receptor antagonists (H3R), Serotonin receptor subtype 4 (5-HT4R) antagonists, Sigma1 receptor antagonists (S1R) and soluble Epoxide Hydrolase (sEH) inhibitors. The drug development strategy of multi-target-directed ligands (MTDLs) offers unique advantages in the treatment of complex diseases. On the one hand, it can synergistically enhance the therapeutic efficacy of single-target drugs. On the other hand, it can also reduce the side effects. In this review, we discuss the design strategy of dual inhibitors based on acetylcholinesterase and the structure-activity relationship of these drugs.

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