Editorial: Insights in Alzheimer's disease and related dementias.
Ontology highlight
ABSTRACT:
SUBMITTER: Ibanez A
PROVIDER: S-EPMC9727773 | biostudies-literature | 2022
REPOSITORIES: biostudies-literature
Publications
Editorial: Insights in Alzheimer's disease and related dementias.
Ibáñez Agustín A Reiss Allison B AB Custodio Nilton N Alladi Suvarna S
Frontiers in aging neuroscience 20221123
Similar Datasets
Project description:Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele.
| S-EPMC9005347 | biostudies-literature
Project description:On March 12-14, 2024, the National Institute on Aging (NIA) together with the National Institute of Neurological Disorders and Stroke (NINDS) led a workshop exploring clinically meaningful changes in the context of Alzheimer's Disease and Alzheimer's Disease Related Dementias (AD/ADRD) clinical trials (https://www.nia.nih.gov/research/dbsr/workshops/clinically-meaningful-outcomes-ad-adrd-trials). The goals were to identify research gaps, opportunities, and tools to advance patient-centered, equitable assessment of clinically meaningful change focused on biomarker status, cognition, and everyday function. The workshop fostered robust, multidisciplinary discussion between lived experience experts, advocates, researchers, clinicians, funders, payers, and regulators. The workshop addressed the criteria used to assess whether an intervention has had a clinically meaningful impact, including consideration of both benefit and harm. Here, we report on (1) criteria to consider for development, testing, and selection of clinically meaningful outcomes in AD/ADRD clinical trials; (2) methods to validate and customize clinically meaningful outcomes that are fit-for-purpose; and (3) practices that will ensure that clinically meaningful outcomes are applicable to diverse populations.HighlightsPatient-Centered Outcomes: Inclusive AD/ADRD clinical trials incorporate assessments that reflect what matters most to those impacted by these diseases, including patient- and caregiver-reported outcome measures. Culturally Relevant Assessments: There is a need for culturally sensitive and equitable assessments to better serve diverse populations in AD/ADRD research. Framework for Clinically Meaningful Change: We present a framework for defining and evaluating clinically meaningful outcomes in AD/ADRD trials, tailored to diverse stages of disease progression. Interdisciplinary Approach: We draw on insights from a multidisciplinary workshop, fostering collaboration among researchers, clinicians, and lived experience experts to advance the field.
| S-EPMC11837731 | biostudies-literature
Project description:The National Alzheimer's Project Act, signed into law in 2011, mandates a National Plan to Address Alzheimer's Disease that is updated annually. In the Plan, the term Alzheimer disease includes not only Alzheimer disease (AD) proper, but also several specified related dementias, namely, frontotemporal, Lewy body, vascular, and mixed dementia. In response to a specific action item in the 2012 National Plan, the National Institute of Neurological Disorders and Stroke, in collaboration with the National Institute on Aging, convened panels of experts and conducted a 2-day public conference to develop research priorities and timelines for addressing Alzheimer disease-related dementias (ADRD) in 5 topic areas: multiple etiology dementias, health disparities, Lewy body dementias including dementia with Lewy bodies and Parkinson disease dementia, frontotemporal dementia and related tauopathies, and vascular contributions to ADRD. By design, the product was up to 8 prioritized research recommendations in each topic area including estimated timelines from when work on a recommendation is started to completion or to full implementation of an ongoing activity, and recognition of shared research themes across recommendations. These included increased education and training of both researchers and health care professionals, addressing health disparities, fundamental neurobiology research, advanced diagnostics, collaborative biosample repositories, and a focus on developing effective interventions to prevent or treat ADRD by the year 2025 as targeted by the National Plan.
| S-EPMC4155046 | biostudies-literature
Project description:Currently, more than 55 million people around the world suffer from dementia, and Alzheimer's disease-related dementia (ADRD) accounts for nearly 60-70% of all those cases. The spread of AD pathology and progressive neurodegeneration in the hippocampus and cerebral cortex is strongly correlated with cognitive decline in AD patients; however, the molecular underpinning of the ADRD causality is still unclear. Studies of postmortem AD brains and animal models of AD suggest that elevated endoplasmic reticulum (ER) stress may have a role in ADRD pathology through altered neurocellular homeostasis in brain regions associated with learning and memory. To study the ER stress-associated neurocellular response and its effects on neurocellular homeostasis and neurogenesis, we modeled an ER stress challenge using Thapsigargin (TG), a specific inhibitor of sarco/endoplasmic reticulum Ca2+ ATPase (SERCA), in induced pluripotent stem cell (iPSC)-derived neural stem cells (NSCs) of two individuals from our Mexican American Family Study (MAFS). High-content screening and transcriptomic analysis of the control and ER stress-challenged NSCs showed that NSC’s ER stress response resulted in a significant decline in NSC self-renewal and an increase in apoptosis and cellular oxidative stress. A total of 2300 genes were significantly (moderated t statistics FDR corrected p-value ≤ 0.05 and Fold Change absolute ≥ 2.0) differentially expressed (DE). Pathway enrichment and gene network analysis of DE genes suggests that all three unfolded protein response (UPR) pathways (PERK, IRE1, and ATF6) were significantly activated and cooperatively regulated the NSC’s transcriptional response to ER stress. Our results show that IRE1/XBP1 mediated transcriptional regulation of E2F1 and its downstream targets have a dominant role in inducing G1/S-phase cell cycle arrest in the ER stress-challenged NSCs. The ER stress-challenged NSCs also showed activation of CHOP-mediated apoptosis and dysregulation of synaptic plasticity and neurotransmitter homeostasis-associated genes. Overall, our results suggest that ER stress-associated attenuation of NSC self-renewal, increased apoptosis, and dysregulated synaptic plasticity and neurotransmitter homeostasis plausibly play a role in the causation of ADRD.
2024-06-05 | GSE263319 | GEO
Project description:We recently nominated cytokine signaling through the Janus-kinase-signal transducer and activator of transcription (JAK/STAT) pathway as a potential AD drug target. As hydroxychloroquine (HCQ) has recently been shown to inactivate STAT3, we hypothesized that it may impact AD pathogenesis and risk. Among 109,124 rheumatoid arthritis patients from routine clinical care, HCQ initiation was associated with a lower risk of incident AD compared to methotrexate initiation across 4 alternative analyses schemes addressing specific types of biases including informative censoring, reverse causality, and outcome misclassification (hazard ratio [95% confidence interval] of 0.92 [0.83-1.00], 0.87 [0.81-0.93], 0.84 [0.76-0.93], and 0.87 [0.75-1.01]). We additionally show that HCQ exerts dose-dependent effects on late long-term potentiation (LTP) and rescues impaired hippocampal synaptic plasticity prior to significant accumulation of amyloid plaques and neurodegeneration in APP/PS1 mice. Additionally, HCQ treatment enhances microglial clearance of Aβ1-42, lowers neuroinflammation, and reduces tau phosphorylation in cell culture-based phenotypic assays. Finally, we show that HCQ inactivates STAT3 in microglia, neurons, and astrocytes suggesting a plausible mechanism associated with its observed effects on AD pathogenesis. HCQ, a relatively safe and inexpensive drug in current use may be a promising disease-modifying AD treatment. This hypothesis merits testing through adequately powered clinical trials in at-risk individuals during preclinical stages of disease progression.
| S-EPMC10005941 | biostudies-literature
Project description:BackgroundRacial disparity in the epidemiology of Alzheimer's disease and Alzheimer's disease-related dementias (AD/ADRD) has been reported. However, less is known about this disparity among Veterans.ObjectiveTo estimate the racial disparity in AD/ADRD among the Veterans.MethodsOf the 5,413,418 Veterans≥65 years receiving care at the Veterans Health Administration (1999-2016), 4,045,269 were free of prevalent AD/ADRD, schizophrenia, or bipolar disorder at baseline. Of these, 432,469 were African American. Race was self-identified and incident AD/ADRD during 20 (median 6.7) years of follow-up was ascertained using International Classification of Diseases codes.ResultsPatients had a mean age of 70.4 (±6.6) years and 97.8% were men. Age-sex-adjusted incidence of AD/ADRD per 1,000 person-year was 19.3 and 10.8 for African American and white Veterans, respectively (age-sex-adjusted hazard ratio associated with African American race, 1.77; 95% confidence interval, 1.75-1.79; p < 0.0001). This association remained essentially unchanged after multivariable adjustment (hazard ratio, 1.67; 95% confidence interval, 1.65-1.69; p < 0.0001). Among the key baseline characteristics that were significant predictors of AD/ADRD in both races, stroke was a significantly stronger predictor among African Americans, and Hispanic ethnicity and depression among whites (p-value for all interaction,<0.0001).ConclusionThe findings of a higher incidence of AD/ADRD among African American Veterans is consistent with the findings in the general population reported in the literature, although the overall incidence appears to be lower than that in the general population. Future studies need to examine this disparity in incidence as well as the between-race heterogeneity in AD/ADRD risk.
| S-EPMC7306894 | biostudies-literature
Project description:IntroductionAlzheimer's disease (AD) and related dementias (ADRD) present significant health challenges. Understanding their underlying biology, advancing existing and new therapies, and enhancing care for patients and caregivers are critical priorities.MethodsThis article utilizes data from the International Alzheimer's and Related Dementias Research Portfolio (IADRP) to analyze funding patterns from the Alzheimer's Association over the past decade.ResultsAs the largest nonprofit funder of AD/ADRD research globally, the Alzheimer's Association has committed over $430 million, supporting a diverse range of studies across the entire spectrum of dementia-related science. The funding landscape has evolved, reflecting new areas of investigation and collaboration with broader research initiatives.DiscussionThis article highlights the dynamic nature of the Association's funding strategies and ongoing efforts to connect funding with additional supportive resources, thereby enhancing the overall research ecosystem Highlights As the world's largest nonprofit funder of Alzheimer's disease and dementia science, the Alzheimer's Association's funding activities are strategically designed in partnership with the global research community to address scientific gaps in our knowledge to advance research. A large part of the Association's funding portfolio depends on key partnerships and collaborations. From 2019 to 2023, the Alzheimer's Association has allocated funding for more than 850 new research studies. The diversity of areas funded is clear across the Association's portfolio. Beyond the Association's strong emphasis on supporting research through grant funding, there are also efforts to ensure the necessary ecosystem to support the career development of researchers and clinicians, maintaining ongoing support for current and future awardees, including convening and the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART).
| S-EPMC11782193 | biostudies-literature
Project description:BackgroundThe ability to rate delirium severity is key to providing optimal care for persons with Alzheimer's Disease and Related Dementias (ADRD). Such ratings would allow clinicians to assess response to treatment, recovery time and prognosis, nursing burden and staffing needs, and to provide nuanced, appropriate patient-centered care. Given the lack of existing tools, we defined content domains for a new delirium severity instrument for use in individuals with mild to moderate ADRD, the DEL-S-AD.MethodsWe built upon our previous study in which we created a content domain framework to inform development of a general delirium severity instrument, the DEL-S. We engaged a new expert panel to discuss issues of measurement in delirium and dementia and to determine which content domains from the prior framework were useful in characterizing delirium severity in ADRD. We also asked panelists to identify new domains. Our panel included eight interdisciplinary members with expertise in delirium and dementia. Panelists participated in two rounds of review followed by two surveys over 2 months.ResultsPanelists endorsed the same content domains as for general delirium severity, including Cognitive, Level of Consciousness, Inattention, Psychiatric-Behavioral, Emotional Dysregulation, Psychomotor Features, and Functional; however, they excluded six of the original subdomains which they considered unhelpful in the context of ADRD: cognitive impairment; anxiety; fear/sense of unease; depression; gait/walking; and incontinence. Debated measurement challenges included assessment at one point in time versus over time, accounting for differences in clinical settings, and accurate assessment of symptoms related to delirium versus dementia.ConclusionsBy capturing a range of characteristics of delirium severity potentially present in patients with ADRD, a population that may already have attention, functional, and emotional changes at baseline, the DEL-S-AD provides a novel rating tool that will be useful for clinical and research purposes to improve patient care.
| S-EPMC9106827 | biostudies-literature
Project description:IntroductionCircular RNAs (circRNAs) exhibit selective expression in the brain and differential regulation in Alzheimer's disease (AD). To explore the role of circRNAs in AD, we investigated how circRNA expression varies between brain regions and with AD-related stress in human neuronal precursor cells (NPCs).MethodsRibosomal RNA-depleted hippocampus RNA-sequencing data were generated. Differentially regulated circRNAs in AD and related dementias were detected using CIRCexplorer3 and limma. circRNA results were validated using quantitative real-time PCR of cDNA from the brain and NPCs.ResultsWe identified 48 circRNAs that were significantly associated with AD. We observed that circRNA expression differed by dementia subtype. Using NPCs, we demonstrated that exposure to oligomeric tau elicits downregulation of circRNA similar to that observed in the AD brain.DiscussionOur study shows that differential expression of circRNA can vary by dementia subtype and brain region. We also demonstrated that circRNAs can be regulated by AD-linked neuronal stress independently from their cognate linear messenger RNAs (mRNAs).
| S-EPMC10427739 | biostudies-literature
Project description:Claims data are a valuable resource for studying Alzheimer's disease and related dementias (ADRD). Alzheimer's disease and related dementias is often identified using a list of claims codes and a fixed lookback period of 3 years of data. However, a 1-year lookback or an approach using all-available lookback data could be beneficial based on different research questions. Thus, the purpose of this study was to compare 1-year and all-available lookback approaches to ascertaining ADRD compared to the standard 3-year approach. Using a cohort of Veterans hospitalized for heart failure (N = 373, 897), our results suggested high agreement (93% or greater) between the lookback periods. The 1-year lookback period had lower sensitivity (60%) and underestimated the prevalence of ADRD. These results suggest that 1-year and all-available lookback periods are viable approaches when using claims data.
| S-EPMC10623942 | biostudies-literature