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1.
Neural Regen Res ; 20(6): 1555-1564, 2025 Jun 01.
Article in English | MEDLINE | ID: mdl-38993140

ABSTRACT

Irisin is a myokine that is generated by cleavage of the membrane protein fibronectin type III domain-containing protein 5 (FNDC5) in response to physical exercise. Studies reveal that irisin/FNDC5 has neuroprotective functions against Alzheimer's disease, the most common form of dementia in the elderly, by improving cognitive function and reducing amyloid-ß and tau pathologies as well as neuroinflammation in cell culture or animal models of Alzheimer's disease. Although current and ongoing studies on irisin/FNDC5 show promising results, further mechanistic studies are required to clarify its potential as a meaningful therapeutic target for alleviating Alzheimer's disease. We recently found that irisin treatment reduces amyloid-ß pathology by increasing the activity/levels of amyloid-ß-degrading enzyme neprilysin secreted from astrocytes. Herein, we present an overview of irisin/FNDC5's protective roles and mechanisms against Alzheimer's disease.

2.
Biomaterials ; 314: 122864, 2024 Sep 28.
Article in English | MEDLINE | ID: mdl-39357152

ABSTRACT

The blood-brain barrier (BBB) serves as a selective filter that prevents harmful substances from entering the healthy brain. Dysfunction of this barrier is implicated in several neurological diseases. In the context of Alzheimer's disease (AD), BBB breakdown plays a significant role in both the initiation and progression of the disease. This study introduces a three-dimensional (3D) self-assembled in vitro model of the human neurovascular unit to recapitulate some of the complex interactions between the BBB and AD pathologies. It incorporates primary human brain endothelial cells, pericytes and astrocytes, and stem cell-derived neurons and astrocytes harboring Familial AD (FAD) mutations. Over an extended co-culture period, the model demonstrates increased BBB permeability, dysregulation of key endothelial and pericyte markers, and morphological alterations mirroring AD pathologies. The model enables visualization of amyloid-beta (Aß) accumulation in both neuronal and vascular compartments. This model may serve as a versatile tool for neuroscience research and drug development to provide insights into the dynamic relationship between vascular dysfunction and AD pathogenesis.

3.
STAR Protoc ; 5(4): 103364, 2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39378155

ABSTRACT

Mast cells, which constitute tissue-resident immune cells, are distributed in the dural meninges. Here, we provide procedural guidelines for investigating mouse dural mast cells using two techniques. First, we outline the procedures for dural tissue dissection, single-cell isolation, and subsequent surface staining for mast cell identification via flow cytometry. We then describe the techniques employed for whole dura tissue staining to visualize mast cells using confocal and slide scanning microscopy, followed by analysis using Nikon's NIS-Elements Advanced Research software. For complete details on the use and execution of this protocol, please refer to Lin et al.1.

4.
Alzheimers Dement ; 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39316411

ABSTRACT

The tauopathies are defined by pathological tau protein aggregates within a spectrum of clinically heterogeneous neurodegenerative diseases. The primary tauopathies meet the definition of rare diseases in the United States. There is no approved treatment for primary tauopathies. In this context, designing the most efficient development programs to translate promising targets and treatments from preclinical studies to early-phase clinical trials is vital. In September 2022, the Rainwater Charitable Foundation convened an international expert workshop focused on the translation of tauopathy therapeutics through early-phase trials. Our report on the workshop recommends a framework for principled drug development and a companion lexicon to facilitate communication focusing on reproducibility and achieving common elements. Topics include the selection of targets, drugs, biomarkers, participants, and study designs. The maturation of pharmacodynamic biomarkers to demonstrate target engagement and surrogate disease biomarkers is a crucial unmet need. HIGHLIGHTS: Experts provided a framework to translate therapeutics (discovery to clinical trials). Experts focused on the "5 Rights" (target, drug, biomarker, participants, trial). Current research on frontotemporal degeneration, progressive supranuclear palsy, and corticobasal syndrome therapeutics includes 32 trials (37% on biologics) Tau therapeutics are being tested in Alzheimer's disease; primary tauopathies have a large unmet need.

5.
Cell Rep Methods ; 4(9): 100846, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39241776

ABSTRACT

Monocytes are critical to innate immunity, participating in chemotaxis during tissue injury, infection, and inflammatory conditions. However, the migration dynamics of human monocytes under different guidance cues are not well characterized. Here, we developed a microfluidic device to profile the migration characteristics of human monocytes under chemotactic and barotactic guidance cues while also assessing the effects of age and cytokine stimulation. Human monocytes preferentially migrated toward the CCL2 gradient through confined microchannels, regardless of donor age and migration pathway. Stimulation with interferon (IFN)-γ, but not granulocyte-macrophage colony-stimulating factor (GM-CSF), disrupted monocyte navigation through complex paths and decreased monocyte CCL2 chemotaxis, velocity, and CCR2 expression. Additionally, monocytes exhibited a bias toward low-hydraulic-resistance pathways in asymmetric environments, which remained consistent across donor ages, cytokine stimulation, and chemoattractants. This microfluidic system provides insights into the unique migratory behaviors of human monocytes and is a valuable tool for studying peripheral immune cell migration in health and disease.


Subject(s)
Cell Movement , Chemotaxis , Monocytes , Humans , Monocytes/immunology , Monocytes/metabolism , Monocytes/drug effects , Cell Movement/drug effects , Chemotaxis/drug effects , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Chemokine CCL2/metabolism , Interferon-gamma/pharmacology , Interferon-gamma/metabolism , Receptors, CCR2/metabolism , Adult
6.
ACS Chem Neurosci ; 15(19): 3576-3586, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39297418

ABSTRACT

Considerable evidence indicates that the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome plays key roles in human pathophysiology, suggesting it as a potential drug target. Currently, studies have yet to develop compounds that are promising therapeutics in the clinic by targeting the NLRP3 inflammasome. Herein, we aim to further biologically characterize a previously identified small-molecule inhibitor of the NLRP3 inflammasome from our group, YM-I-26, to confirm its functional activities. We showed that YM-I-26 is highly selective toward the NLRP3 inflammasome and binds to NLRP3 directly. A systemic analysis revealed YM-I-26 with inflammation-related and immunomodulatory activities by the Eurofins BioMAP Diversity PLUS panel. In addition, studies using the mouse microglia BV2 cell model demonstrated that YM-I-26 is not cytotoxic, improved the phagocytotic functions of BV2 cells toward beta-amyloid, and suppressed the production of cytokines of IL-1ß and IL-10 upon the activation of the NLRP3 inflammasome. Collectively, our studies support the functional activities of YM-I-26 as a NLRP3 inhibitor in physiologically relevant cell models, and warrant future studies of YM-I-26 and its analogs to advance the drug development as potential therapeutics.


Subject(s)
Inflammasomes , Microglia , NLR Family, Pyrin Domain-Containing 3 Protein , Sulfonamides , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors , Sulfonamides/pharmacology , Animals , Inflammasomes/metabolism , Inflammasomes/drug effects , Mice , Microglia/drug effects , Microglia/metabolism , Humans , Cell Line
7.
J Infect Dis ; 230(Supplement_2): S150-S164, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39255393

ABSTRACT

Sensory functions of organs of the head and neck allow humans to interact with the environment and establish social bonds. With aging, smell, taste, vision, and hearing decline. Evidence suggests that accelerated impairment in sensory abilities can reflect a shift from healthy to pathological aging, including the development of Alzheimer's disease (AD) and other neurological disorders. While the drivers of early sensory alteration in AD are not elucidated, insults such as trauma and infections can affect sensory function. Herein, we review the involvement of the major head and neck sensory systems in AD, with emphasis on microbes exploiting sensory pathways to enter the brain (the "gateway" hypothesis) and the potential feedback loop by which sensory function may be impacted by central nervous system infection. We emphasize detection of sensory changes as first-line surveillance in senior adults to identify and remove potential insults, like microbial infections, that could precipitate brain pathology.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/physiopathology , Alzheimer Disease/microbiology , Brain/pathology , Brain/physiopathology , Sensation Disorders/physiopathology , Sensation Disorders/microbiology , Aging/physiology
8.
medRxiv ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39314934

ABSTRACT

Alzheimer's disease (AD) is the most prevalent form of dementia. While many AD-associated genetic determinants have been previously identified, few studies have analyzed individuals of non-European ancestry. Here, we describe a multi-ancestry genome-wide association study of clinically-diagnosed AD and AD-by-proxy using whole genome sequencing data from NIAGADS, NIMH, UKB, and All of Us (AoU) consisting of 49,149 cases (12,074 clinically-diagnosed and 37,075 AD-by-proxy) and 383,225 controls. Nearly half of NIAGADS and AoU participants are of non-European ancestry. For clinically-diagnosed AD, we identified 14 new loci - five common (FBN2,/SCL27A6, AC090115.1, DYM, KCNG1/AL121785.1, TIAM1) and nine rare (VWA5B1, RNU6-755P/LMX1A, MOB1A, MORC1-AS1, LINC00989, PDE4D, RNU2-49P/CDO1, NEO1, and SLC35G3/AC022916.1). Meta-analysis of UKB and AoU AD-by-proxy cases yielded two new rare loci (RPL23/LASP1 and CEBPA/ AC008738.6) which were also nominally significant in NIAGADS. In summary, we provide evidence for 16 novel AD loci and advocate for more studies using WGS-based GWAS of diverse cohorts.

9.
Alzheimers Dement (N Y) ; 10(3): e12487, 2024.
Article in English | MEDLINE | ID: mdl-39131742

ABSTRACT

INTRODUCTION: Sodium phenylbutyrate and taurursodiol (PB and TURSO) is hypothesized to mitigate endoplasmic reticulum stress and mitochondrial dysfunction, two of many mechanisms implicated in Alzheimer's disease (AD) pathophysiology. METHODS: The first-in-indication phase 2a PEGASUS trial was designed to gain insight into PB and TURSO effects on mechanistic targets of engagement and disease biology in AD. The primary clinical efficacy outcome was a global statistical test combining three endpoints relevant to disease trajectory (cognition [Mild/Moderate Alzheimer's Disease Composite Score], function [Functional Activities Questionnaire], and total hippocampal volume on magnetic resonance imaging). Secondary clinical outcomes included various cognitive, functional, and neuropsychiatric assessments. Cerebrospinal fluid (CSF) biomarkers spanning multiple pathophysiological pathways in AD were evaluated in participants with both baseline and Week 24 samples (exploratory outcome). RESULTS: PEGASUS enrolled 95 participants (intent-to-treat [ITT] cohort); cognitive assessments indicated significantly greater baseline cognitive impairment in the PB and TURSO (n = 51) versus placebo (n = 44) group. Clinical efficacy outcomes did not significantly differ between treatment groups in the ITT cohort. CSF interleukin-15 increased from baseline to Week 24 within the placebo group (n = 34). In the PB and TURSO group (n = 33), reductions were observed in core AD biomarkers phosphorylated tau-181 (p-tau181) and total tau; synaptic and neuronal degeneration biomarkers neurogranin and fatty acid binding protein-3 (FABP3); and gliosis biomarker chitinase 3-like protein 1 (YKL-40), while the oxidative stress marker 8-hydroxy-2-deoxyguanosine (8-OHdG) increased. Between-group differences were observed for the Aß42/40 ratio, p-tau181, total tau, neurogranin, FABP3, YKL-40, interleukin-15, and 8-OHdG. Additional neurodegeneration, inflammation, and metabolic biomarkers showed no differences between groups. DISCUSSION: While between-group differences in clinical outcomes were not observed, most likely due to the small sample size and relatively short treatment duration, exploratory biomarker analyses suggested that PB and TURSO engages multiple pathophysiologic pathways in AD. Highlights: Proteostasis and mitochondrial stress play key roles in Alzheimer's disease (AD).Sodium phenylbutyrate and taurursodiol (PB and TURSO) targets these mechanisms.The PEGASUS trial was designed to assess PB and TURSO effects on biologic AD targets.PB and TURSO reduced exploratory biomarkers of AD and neurodegeneration.Supports further clinical development of PB and TURSO in neurodegenerative diseases.

10.
Front Psychiatry ; 15: 1373797, 2024.
Article in English | MEDLINE | ID: mdl-39109366

ABSTRACT

Introduction: The 21-point Brain Care Score (BCS) is a novel tool designed to motivate individuals and care providers to take action to reduce the risk of stroke and dementia by encouraging lifestyle changes. Given that late-life depression is increasingly recognized to share risk factors with stroke and dementia, and is an important clinical endpoint for brain health, we tested the hypothesis that a higher BCS is associated with a reduced incidence of future depression. Additionally, we examined its association with a brain health composite outcome comprising stroke, dementia, and late-life depression. Methods: The BCS was derived from the United Kingdom Biobank baseline evaluation in participants with complete data on BCS items. Associations of BCS with the risk of subsequent incident late-life depression and the composite brain health outcome were estimated using multivariable Cox proportional hazard models. These models were adjusted for age at baseline and sex assigned at birth. Results: A total of 363,323 participants were included in this analysis, with a median BCS at baseline of 12 (IQR: 11-14). There were 6,628 incident cases of late-life depression during a median follow-up period of 13 years. Each five-point increase in baseline BCS was associated with a 33% lower risk of incident late-life depression (95% CI: 29%-36%) and a 27% lower risk of the incident composite outcome (95% CI: 24%-30%). Discussion: These data further demonstrate the shared risk factors across depression, dementia, and stroke. The findings suggest that a higher BCS, indicative of healthier lifestyle choices, is significantly associated with a lower incidence of late-life depression and a composite brain health outcome. Additional validation of the BCS is warranted to assess the weighting of its components, its motivational aspects, and its acceptability and adaptability in routine clinical care worldwide.

11.
Science ; 385(6708): adl2992, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39088624

ABSTRACT

Late-onset Alzheimer's disease (LOAD) is the most common form of Alzheimer's disease (AD). However, modeling sporadic LOAD that endogenously captures hallmark neuronal pathologies such as amyloid-ß (Aß) deposition, tau tangles, and neuronal loss remains an unmet need. We demonstrate that neurons generated by microRNA (miRNA)-based direct reprogramming of fibroblasts from individuals affected by autosomal dominant AD (ADAD) and LOAD in a three-dimensional environment effectively recapitulate key neuropathological features of AD. Reprogrammed LOAD neurons exhibit Aß-dependent neurodegeneration, and treatment with ß- or γ-secretase inhibitors before (but not subsequent to) Aß deposit formation mitigated neuronal death. Moreover inhibiting age-associated retrotransposable elements in LOAD neurons reduced both Aß deposition and neurodegeneration. Our study underscores the efficacy of modeling late-onset neuropathology of LOAD through high-efficiency miRNA-based neuronal reprogramming.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Cellular Reprogramming , Fibroblasts , MicroRNAs , Neurons , Spheroids, Cellular , Humans , Alzheimer Disease/pathology , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid Precursor Protein Secretases/metabolism , Amyloid Precursor Protein Secretases/genetics , Cellular Reprogramming/genetics , Fibroblasts/metabolism , Fibroblasts/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , Neurons/metabolism , Neurons/pathology
12.
Alzheimers Dement ; 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39132765

ABSTRACT

INTRODUCTION: Chronic air pollution (AirPoll) is associated with accelerated cognitive decline and risk of Alzheimer's disease (AD). Correspondingly, wild-type and AD-transgenic rodents exposed to AirPoll have increased amyloid peptides and behavioral impairments. METHODS: We examined the γ-secretase modulator GSM-15606 for potential AirPoll protection by its attenuating of amyloid beta (Aß)42 peptide production. Male and female wild-type mice were fed GSM-15606 during an 8-week inhalation exposure to AirPoll subfractions, ambient nanoparticulate matter (nPM), and diesel exhaust particles (DEP). RESULTS: GSM-15606 decreased Aß42 during nPM and DEP exposure without changing beta- or gamma-secretase activity or BACE1 and PS1 protein levels. DEP increased lateral ventricle volume by 25%. DISCUSSION: These enzyme responses are relevant to AD drug treatments, as well as to the physiological functions of the Aß42 peptide. GSM-15606 attenuation of Aß42 may benefit human exposure to AirPoll. HIGHLIGHTS: Gamma-secretase modulator (GSM-15606) attenuates the amyloidogenic amyloid beta (Aß)42 peptide during exposure to air pollution, which may be a mechanism by which air pollution increases Alzheimer's disease (AD) risk. AD drug treatments may also consider Aß homeostasis among the chronic effects of GSM-15606 and other amyloid reduction treatments on secretase enzymes.

13.
Nature ; 632(8026): 858-868, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39048816

ABSTRACT

Alzheimer's disease is the leading cause of dementia worldwide, but the cellular pathways that underlie its pathological progression across brain regions remain poorly understood1-3. Here we report a single-cell transcriptomic atlas of six different brain regions in the aged human brain, covering 1.3 million cells from 283 post-mortem human brain samples across 48 individuals with and without Alzheimer's disease. We identify 76 cell types, including region-specific subtypes of astrocytes and excitatory neurons and an inhibitory interneuron population unique to the thalamus and distinct from canonical inhibitory subclasses. We identify vulnerable populations of excitatory and inhibitory neurons that are depleted in specific brain regions in Alzheimer's disease, and provide evidence that the Reelin signalling pathway is involved in modulating the vulnerability of these neurons. We develop a scalable method for discovering gene modules, which we use to identify cell-type-specific and region-specific modules that are altered in Alzheimer's disease and to annotate transcriptomic differences associated with diverse pathological variables. We identify an astrocyte program that is associated with cognitive resilience to Alzheimer's disease pathology, tying choline metabolism and polyamine biosynthesis in astrocytes to preserved cognitive function late in life. Together, our study develops a regional atlas of the ageing human brain and provides insights into cellular vulnerability, response and resilience to Alzheimer's disease pathology.


Subject(s)
Alzheimer Disease , Brain , Gene Expression Profiling , Single-Cell Analysis , Aged, 80 and over , Animals , Female , Humans , Male , Mice , Aging/metabolism , Aging/pathology , Alzheimer Disease/pathology , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Astrocytes/classification , Astrocytes/cytology , Astrocytes/metabolism , Astrocytes/pathology , Autopsy , Brain/anatomy & histology , Brain/cytology , Brain/metabolism , Brain/pathology , Case-Control Studies , Choline/metabolism , Cognition/physiology , Gene Regulatory Networks , Interneurons/classification , Interneurons/cytology , Interneurons/metabolism , Interneurons/pathology , Nerve Tissue Proteins/metabolism , Nerve Tissue Proteins/genetics , Neural Inhibition , Neurons/classification , Neurons/cytology , Neurons/metabolism , Neurons/pathology , Polyamines/metabolism , Reelin Protein , Signal Transduction , Thalamus/cytology , Thalamus/metabolism , Thalamus/pathology , Transcriptome
14.
medRxiv ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38978657

ABSTRACT

Although the genetic locus of X-linked dystonia parkinsonism (XDP), a neurodegenerative disease endemic in the Philippines, is well-characterized, the exact molecular mechanisms leading to neuronal loss are not yet fully understood. Recently, we demonstrated a significant increase in astrogliosis and microgliosis together with an increase in myeloperoxidase (MPO) levels in XDP post-mortem prefrontal cortex (PFC), suggesting a role for neuroinflammation in XDP pathogenesis. Here, we demonstrated a significant increase in MPO activity in XDP PFC using a novel specific MPO-activatable fluorescent agent (MAFA). Additionally, we demonstrated a significant increase in reactive oxygen species (ROS) in XDP-derived fibroblasts as well as in SH-SY5Y cells treated with post-mortem XDP PFC, further supporting a role for MPO in XDP. To determine whether increases in MPO activity were linked to increases in ROS, MPO content was immuno-depleted from XDP PFC [MPO(-)], which resulted in a significant decrease in ROS in SH-SY5Y cells. Consistently, the treatment with verdiperstat, a potent and selective MPO inhibitor, significantly decreased ROS in both XDP-derived fibroblasts and XDP PFC-treated SH-SY5Y cells. Collectively, our results suggest that MPO inhibition mitigates oxidative stress and may provide a novel therapeutic strategy for XDP treatment. Highlights: MPO activity is increased in XDP post-mortem prefrontal cortex.MPO activity is increased in cellular models of XDP.MPO increases reactive oxygen species (ROS) in vitro.Inhibiting MPO mitigates ROS in XDP.The MPO inhibitor, verdiperstat, dampens ROS suggesting a potential therapeutic strategy for XDP.

15.
Genet Epidemiol ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982682

ABSTRACT

The prediction of the susceptibility of an individual to a certain disease is an important and timely research area. An established technique is to estimate the risk of an individual with the help of an integrated risk model, that is, a polygenic risk score with added epidemiological covariates. However, integrated risk models do not capture any time dependence, and may provide a point estimate of the relative risk with respect to a reference population. The aim of this work is twofold. First, we explore and advocate the idea of predicting the time-dependent hazard and survival (defined as disease-free time) of an individual for the onset of a disease. This provides a practitioner with a much more differentiated view of absolute survival as a function of time. Second, to compute the time-dependent risk of an individual, we use published methodology to fit a Cox's proportional hazard model to data from a genetic SNP study of time to Alzheimer's disease (AD) onset, using the lasso to incorporate further epidemiological variables such as sex, APOE (apolipoprotein E, a genetic risk factor for AD) status, 10 leading principal components, and selected genomic loci. We apply the lasso for Cox's proportional hazards to a data set of 6792 AD patients (composed of 4102 cases and 2690 controls) and 87 covariates. We demonstrate that fitting a lasso model for Cox's proportional hazards allows one to obtain more accurate survival curves than with state-of-the-art (likelihood-based) methods. Moreover, the methodology allows one to obtain personalized survival curves for a patient, thus giving a much more differentiated view of the expected progression of a disease than the view offered by integrated risk models. The runtime to compute personalized survival curves is under a minute for the entire data set of AD patients, thus enabling it to handle datasets with 60,000-100,000 subjects in less than 1 h.

16.
Life (Basel) ; 14(7)2024 Jul 08.
Article in English | MEDLINE | ID: mdl-39063609

ABSTRACT

BACKGROUNDS: Sleep disturbances are prevalent among elderly individuals. While polysomnography (PSG) serves as the gold standard for sleep monitoring, its extensive setup and data analysis procedures impose significant costs and time constraints, thereby restricting the long-term application within the general public. Our laboratory introduced an innovative biomarker, utilizing artificial intelligence algorithms applied to PSG data to estimate brain age (BA), a metric validated in cohorts with cognitive impairments. Nevertheless, the potential of exercise, which has been a recognized means of enhancing sleep quality in middle-aged and older adults to reduce BA, remains undetermined. METHODS: We conducted an exploratory study to evaluate whether 12 weeks of moderate-intensity exercise can improve cognitive function, sleep quality, and the brain age index (BAI), a biomarker computed from overnight sleep electroencephalogram (EEG), in physically inactive middle-aged and older adults. Home wearable devices were used to monitor heart rate and overnight sleep EEG over this period. The NIH Toolbox Cognition Battery, in-lab overnight polysomnography, cardiopulmonary exercise testing, and a multiplex cytokines assay were employed to compare pre- and post-exercise brain health, exercise capacity, and plasma proteins. RESULTS: In total, 26 participants completed the initial assessment and exercise program, and 24 completed all procedures. Data are presented as mean [lower 95% CI of mean, upper 95% CI of mean]. Participants significantly increased maximal oxygen consumption (Pre: 21.11 [18.98, 23.23], Post 22.39 [20.09, 24.68], mL/kg/min; effect size: -0.33) and decreased resting heart rate (Pre: 66.66 [63.62, 67.38], Post: 65.13 [64.25, 66.93], bpm; effect size: -0.02) and sleeping heart rate (Pre: 64.55 [61.87, 667.23], Post: 62.93 [60.78, 65.09], bpm; effect size: -0.15). Total cognitive performance (Pre: 111.1 [107.6, 114.6], Post: 115.2 [111.9, 118.5]; effect size: 0.49) was significantly improved. No significant differences were seen in BAI or measures of sleep macro- and micro-architecture. Plasma IL-4 (Pre: 0.24 [0.18, 0.3], Post: 0.33 [0.24, 0.42], pg/mL; effect size: 0.49) was elevated, while IL-8 (Pre: 5.5 [4.45, 6.55], Post: 4.3 [3.66, 5], pg/mL; effect size: -0.57) was reduced. CONCLUSIONS: Cognitive function was improved by a 12-week moderate-intensity exercise program in physically inactive middle-aged and older adults, as were aerobic fitness (VO2max) and plasma cytokine profiles. However, we found no measurable effects on sleep architecture or BAI. It remains to be seen whether a study with a larger sample size and more intensive or more prolonged exercise exposure can demonstrate a beneficial effect on sleep quality and brain age.

17.
Neurology ; 103(4): e209687, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39052961

ABSTRACT

OBJECTIVES: To investigate associations between health-related behaviors as measured using the Brain Care Score (BCS) and neuroimaging markers of white matter injury. METHODS: This prospective cohort study in the UK Biobank assessed the BCS, a novel tool designed to empower patients to address 12 dementia and stroke risk factors. The BCS ranges from 0 to 21, with higher scores suggesting better brain care. Outcomes included white matter hyperintensities (WMH) volume, fractional anisotropy (FA), and mean diffusivity (MD) obtained during 2 imaging assessments, as well as their progression between assessments, using multivariable linear regression adjusted for age and sex. RESULTS: We included 34,509 participants (average age 55 years, 53% female) with no stroke or dementia history. At first and repeat imaging assessments, every 5-point increase in baseline BCS was linked to significantly lower WMH volumes (25% 95% CI [23%-27%] first, 33% [27%-39%] repeat) and higher FA (18% [16%-20%] first, 22% [15%-28%] repeat), with a decrease in MD (9% [7%-11%] first, 10% [4%-16%] repeat). In addition, a higher baseline BCS was associated with a 10% [3%-17%] reduction in WMH progression and FA decline over time. DISCUSSION: This study extends the impact of the BCS to neuroimaging markers of clinically silent cerebrovascular disease. Our results suggest that improving one's BCS could be a valuable intervention to prevent early brain health decline.


Subject(s)
Neuroimaging , Humans , Female , Male , Middle Aged , Neuroimaging/methods , Prospective Studies , Brain/diagnostic imaging , White Matter/diagnostic imaging , White Matter/pathology , Magnetic Resonance Imaging , Cohort Studies , Diffusion Tensor Imaging , Risk Factors , Aged , Adult
18.
Brief Bioinform ; 25(4)2024 May 23.
Article in English | MEDLINE | ID: mdl-38836403

ABSTRACT

In precision medicine, both predicting the disease susceptibility of an individual and forecasting its disease-free survival are areas of key research. Besides the classical epidemiological predictor variables, data from multiple (omic) platforms are increasingly available. To integrate this wealth of information, we propose new methodology to combine both cooperative learning, a recent approach to leverage the predictive power of several datasets, and polygenic hazard score models. Polygenic hazard score models provide a practitioner with a more differentiated view of the predicted disease-free survival than the one given by merely a point estimate, for instance computed with a polygenic risk score. Our aim is to leverage the advantages of cooperative learning for the computation of polygenic hazard score models via Cox's proportional hazard model, thereby improving the prediction of the disease-free survival. In our experimental study, we apply our methodology to forecast the disease-free survival for Alzheimer's disease (AD) using three layers of data. One layer contains epidemiological variables such as sex, APOE (apolipoprotein E, a genetic risk factor for AD) status and 10 leading principal components. Another layer contains selected genomic loci, and the last layer contains methylation data for selected CpG sites. We demonstrate that the survival curves computed via cooperative learning yield an AUC of around $0.7$, above the state-of-the-art performance of its competitors. Importantly, the proposed methodology returns (1) a linear score that can be easily interpreted (in contrast to machine learning approaches), and (2) a weighting of the predictive power of the involved data layers, allowing for an assessment of the importance of each omic (or other) platform. Similarly to polygenic hazard score models, our methodology also allows one to compute individual survival curves for each patient.


Subject(s)
Alzheimer Disease , Precision Medicine , Humans , Precision Medicine/methods , Alzheimer Disease/genetics , Alzheimer Disease/mortality , Disease-Free Survival , Machine Learning , Proportional Hazards Models , Multifactorial Inheritance , Male , Female , Multiomics
19.
Adv Sci (Weinh) ; 11(32): e2309021, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38923244

ABSTRACT

Targeting receptor-interacting protein kinase 1 (RIPK1) has emerged as a promising therapeutic stratagem for neurodegenerative disorders, particularly Alzheimer's disease (AD). A positron emission tomography (PET) probe enabling brain RIPK1 imaging can provide a powerful tool to unveil the neuropathology associated with RIPK1. Herein, the development of a new PET radioligand, [11C]CNY-10 is reported, which may enable brain RIPK1 imaging. [11C]CNY-10 is radiosynthesized with a high radiochemical yield (41.8%) and molar activity (305 GBq/µmol). [11C]CNY-10 is characterized by PET imaging in rodents and a non-human primate, demonstrating good brain penetration, binding specificity, and a suitable clearance kinetic profile. It is performed autoradiography of [11C]CNY-10 in human AD and healthy control postmortem brain tissues, which shows strong radiosignal in AD brains higher than healthy controls. Subsequently, it is conducted further characterization of RIPK1 in AD using [11C]CNY-10-based PET studies in combination with immunohistochemistry leveraging the 5xFAD mouse model. It is found that AD mice revealed RIPK1 brain signal significantly higher than WT control mice and that RIPK1 is closely related to amyloid plaques in the brain. The studies enable further translational studies of [11C]CNY-10 for AD and potentially other RIPK1-related human studies.


Subject(s)
Alzheimer Disease , Brain , Positron-Emission Tomography , Receptor-Interacting Protein Serine-Threonine Kinases , Alzheimer Disease/metabolism , Alzheimer Disease/diagnostic imaging , Animals , Positron-Emission Tomography/methods , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Mice , Brain/diagnostic imaging , Brain/metabolism , Humans , Disease Models, Animal , Radiopharmaceuticals/metabolism , Radiopharmaceuticals/pharmacokinetics , Male , Rats , Female , Autoradiography/methods , Carbon Radioisotopes/metabolism
20.
Alzheimers Res Ther ; 16(1): 122, 2024 06 07.
Article in English | MEDLINE | ID: mdl-38849944

ABSTRACT

BACKGROUND: Evidence links lifestyle factors with Alzheimer's disease (AD). We report the first randomized, controlled clinical trial to determine if intensive lifestyle changes may beneficially affect the progression of mild cognitive impairment (MCI) or early dementia due to AD. METHODS: A 1:1 multicenter randomized controlled phase 2 trial, ages 45-90 with MCI or early dementia due to AD and a Montreal Cognitive Assessment (MoCA) score of 18 or higher. The primary outcome measures were changes in cognition and function tests: Clinical Global Impression of Change (CGIC), Alzheimer's Disease Assessment Scale (ADAS-Cog), Clinical Dementia Rating-Sum of Boxes (CDR-SB), and Clinical Dementia Rating Global (CDR-G) after 20 weeks of an intensive multidomain lifestyle intervention compared to a wait-list usual care control group. ADAS-Cog, CDR-SB, and CDR-Global scales were compared using a Mann-Whitney-Wilcoxon rank-sum test, and CGIC was compared using Fisher's exact test. Secondary outcomes included plasma Aß42/40 ratio, other biomarkers, and correlating lifestyle with the degree of change in these measures. RESULTS: Fifty-one AD patients enrolled, mean age 73.5. No significant differences in any measures at baseline. Only two patients withdrew. All patients had plasma Aß42/40 ratios <0.0672 at baseline, strongly supporting AD diagnosis. After 20 weeks, significant between-group differences in the CGIC (p= 0.001), CDR-SB (p= 0.032), and CDR Global (p= 0.037) tests and borderline significance in the ADAS-Cog test (p= 0.053). CGIC, CDR Global, and ADAS-Cog showed improvement in cognition and function and CDR-SB showed significantly less progression, compared to the control group which worsened in all four measures. Aß42/40 ratio increased in the intervention group and decreased in the control group (p = 0.003). There was a significant correlation between lifestyle and both cognitive function and the plasma Aß42/40 ratio. The microbiome improved only in the intervention group (p <0.0001). CONCLUSIONS: Comprehensive lifestyle changes may significantly improve cognition and function after 20 weeks in many patients with MCI or early dementia due to AD. TRIAL REGISTRATION: Approved by Western Institutional Review Board on 12/31/2017 (#20172897) and by Institutional Review Boards of all sites. This study was registered retrospectively with clinicaltrials.gov on October 8, 2020 (NCT04606420, ID: 20172897).


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Disease Progression , Life Style , Humans , Male , Female , Aged , Alzheimer Disease/psychology , Aged, 80 and over , Middle Aged , Dementia/psychology , Amyloid beta-Peptides/blood , Neuropsychological Tests , Treatment Outcome
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