Connectivity as a universal predictor of tau progression in atypical Alzheimer's disease.

The link between regional tau load and clinical manifestation of Alzheimer's disease (AD) highlights the importance of characterizing spatial tau distribution across disease variants. In typical (memory-predominant) AD, the spatial progression of tau pathology mirrors the functional connections from temporal lobe epicenters. However, given the limited spatial heterogeneity of tau in typical AD, atypical (non-amnestic-predominant) AD variants with distinct tau patterns provide a key opportunity to investigate the universality of connectivity as a scaffold for tau progression.

High-sensitivity plasma proteomics reveals disease-specific signatures and predictive biomarkers of Alzheimer's disease phenotypes in a large mixed dementia cohort.

Highly sensitive plasma assays enable accurate blood-based biomarkers for neurodegenerative disease and provide minimally invasive options for clinical use. Large-scale studies encompassing multiple neurodegenerative diseases and utilizing multiplex platforms are essential to uncover disease-specific biomarkers and pathways. We generated and analyzed plasma proteomics using the NULISASeq CNS Disease Panel 120 from 3,002 participants with Alzheimer disease (AD), Dementia with Lewy bodies (DLB), Frontotemporal dementia (FTD), Parkinson disease (PD) and cognitively unimpaired participants at the Charles F.

Baseline and longitudinal changes in cortical thickness and hippocampal volume predict cognitive decline.

BackgroundAs we transition to disease-modifying treatment for Alzheimer's disease (AD), identifying individuals most at risk for future cognitive decline is crucial. Amyloid PET, cerebrospinal fluid and more recently blood-based biomarkers can identify the first stage of AD. However, changes detectable by PiB-PET may precede the onset of the dementia by 20-30 years.

Regional effects of gantenerumab on neuroimaging biomarkers in the DIAN-TU-001 trial.

Introduction: Monoclonal anti-amyloid therapies are now accessible, but how these treatments influence changes within the brain is still not clear. We investigated overall and regional change in amyloid removal, glucose metabolism, and atrophy in trial participants with dominantly inherited Alzheimer's disease (DIAD).

Methods: In the DIAN-TU-001 trial, 92 carriers received gantenerumab or placebo and underwent serial neuroimaging assessments including [C]-Pittsburgh compound-B (PiB) positron emission tomography (PET), [F]-fluoro-2-deoxyglucose (FDG) PET, and magnetic resonance imaging (MRI).

Clinical use and reporting of neurofilament quantification in neurological disorders: A global overview.

Introduction: Neurofilament light chain (NfL) quantification aids in diagnosing and predicting neurological disorders, but clinical and laboratory practices vary across centers. Differences in result interpretation and reporting further challenge test commutability. This study aimed to review the global analytical and post-analytical methods used for NfL measurement in routine clinical practice across different contexts.

Immunohistochemical evaluation of a trial of gantenerumab or solanezumab in dominantly inherited Alzheimer disease.

Clinical trials of anti-amyloid-β (Aβ) monoclonal antibodies in Alzheimer disease (AD) infer target engagement from Aβ positron emission tomography (PET) and/or fluid biomarkers such as cerebrospinal fluid (CSF) Aβ42/40. However, these biomarkers measure brain Aβ deposits indirectly and/or incompletely. In contrast, neuropathologic assessments allow direct investigation of treatment effects on brain Aβ deposits-and on potentially myriad 'downstream' pathologic features.

Ubiquitin-proteasome system in the different stages of dominantly inherited Alzheimer's disease.

Introduction: This study investigated the role of the ubiquitin-proteasome system (UPS) in dominantly inherited Alzheimer's disease (DIAD) by examining cerebrospinal fluid (CSF) levels of UPS proteins.

Method: The SOMAscan assay was used to detect changes in UPS proteins in mutation carriers (MCs) relative to disease progression; imaging and CSF biomarkers of amyloid, tau, and neurodegeneration measures; and Clinical Dementia Rating scale.

Results: Subtle increases in specific ubiquitin enzymes were detected in MCs up to two decades before symptom onset, with more pronounced elevations in UPS-activating enzymes near symptom onset.

Analyzing heterogeneity in Alzheimer disease using multimodal normative modeling on imaging-based ATN biomarkers.

Introduction: Previous studies have applied normative modeling on a single neuroimaging modality to investigate Alzheimer disease (AD) heterogeneity. We employed a deep learning-based multimodal normative framework to analyze individual-level variation across ATN (amyloid-tau-neurodegeneration) imaging biomarkers.

Methods: We selected cross-sectional discovery (n = 665) and replication cohorts (n = 430) with available T1-weighted magnetic resonance imaging (MRI), amyloid, and tau positron emission tomography (PET).

[C]ER176 images brain inflammation across TSPO genotypes and colocalizes with tau.

Accurately measuring brain inflammation in Alzheimer's disease (AD) is crucial due to the role of inflammatory processes in neurodegeneration. In a recent study, Appleton, Finn, et al. used [C]ER176, a novel translocator protein 18 kDa (TSPO)-positron emission tomography (PET) tracer overcoming genotype-related binding issues, to show increased inflammation in early-onset AD, with patterns aligning more closely with tau pathology than amyloid deposition or atrophy.

Safety and efficacy of long-term gantenerumab treatment in dominantly inherited Alzheimer's disease: an open-label extension of the phase 2/3 multicentre, randomised, double-blind, placebo-controlled platform DIAN-TU trial.

Background: Amyloid plaque removal by monoclonal antibody therapies slows clinical progression in symptomatic Alzheimer's disease; however, the potential for delaying the onset of clinical symptoms in asymptomatic people is unknown. The Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU) is an ongoing platform trial assessing the safety and efficacy of multiple investigational products in participants with dominantly inherited Alzheimer's disease (DIAD). Based on findings of amyloid removal and downstream biological effects from the gantenerumab group of the platform trial, we continued a 3-year open-label extension (OLE) study to assess the safety and efficacy of long-term treatment with high doses of gantenerumab.

Sample size estimates for biomarker-based outcome measures in clinical trials in autosomal dominant Alzheimer's disease.

Introduction: Alzheimer disease (AD)-modifying therapies are approved for treatment of early-symptomatic AD. Autosomal dominant AD (ADAD) provides a unique opportunity to test therapies in presymptomatic individuals.

Methods: Using data from the Dominantly Inherited Alzheimer Network (DIAN), sample sizes for clinical trials were estimated for various cognitive, imaging, and CSF outcomes.

Safety and efficacy of long-term gantenerumab treatment in dominantly inherited Alzheimer's disease: an open label extension of the phase 2/3 multicentre, randomised, double-blind, placebo-controlled platform DIAN-TU Trial.

Background: Amyloid-plaque removal by monoclonal antibody therapies slows clinical progression in symptomatic Alzheimer's disease; however, the potential for delaying the onset of clinical symptoms in asymptomatic people is unknown. The Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU) is an ongoing platform trial assessing the safety and efficacy of multiple investigational products in participants with dominantly inherited Alzheimer's disease (DIAD) caused by mutations. On the basis of findings of amyloid removal and downstream biological effects from the gantenerumab arm of the platform trial, we continued a 3-year open-label extension (OLE) study to assess the safety and efficacy of long-term treatment with high doses of gantenerumab.

The landscape of autosomal-dominant Alzheimer's disease: global distribution and age of onset.

We present a comprehensive global analysis of genetic variants associated with autosomal-dominant Alzheimer's disease (ADAD). A total of 550 variants in the APP, PSEN1 and PSEN2 genes were identified, of which 279 were classified as pathogenic or likely pathogenic based on American College of Medical Genetics and Genomics and the Association for Molecular Pathology criteria, utilizing data from the Dominantly Inherited Alzheimer Network (DIAN), literature and public databases. Symptomatic age at onset (AAO) data were estimated for 227 of these variants, allowing detailed characterization of their frequency, pathogenicity and AAO.

Decoding brain structure to stage Alzheimer's disease pathology in Down syndrome.

Introduction: Alzheimer's disease (AD) in Down syndrome (DS) is associated with changes in brain structure. It is unknown if thickness and volumetric changes can identify AD stages and if they are similar to other genetic forms of AD.

Methods: Magnetic resonance imaging scans were collected for 178 DS adults (106 nonclinical, 45 preclinical, and 27 symptomatic).

Increasing hub disruption parallels dementia severity in autosomal dominant Alzheimer's disease.

Hub regions in the brain, recognized for their roles in ensuring efficient information transfer, are vulnerable to pathological alterations in neurodegenerative conditions, including Alzheimer's disease (AD). Computational simulations and animal experiments have hinted at the theory of activity-dependent degeneration as the cause of this hub vulnerability. However, two critical issues remain unresolved.

Sample size estimates for biomarker-based outcome measures in clinical trials in autosomal dominant Alzheimer's disease.

Introduction: Alzheimer disease (AD)-modifying therapies are approved for treatment of early-symptomatic AD. Autosomal dominant AD (ADAD) provides a unique opportunity to test therapies in presymptomatic individuals.

Methods: Using data from the Dominantly Inherited Alzheimer Network (DIAN), sample sizes for clinical trials were estimated for various cognitive, imaging, and CSF outcomes.

Comparative neurofilament light chain trajectories in CSF and plasma in autosomal dominant Alzheimer's disease.

Disease-modifying therapies for Alzheimer's disease (AD) are likely to be most beneficial when initiated in the presymptomatic phase. To track the benefit of such interventions, fluid biomarkers are of great importance, with neurofilament light chain protein (NfL) showing promise for monitoring neurodegeneration and predicting cognitive outcomes. Here, we update and complement previous findings from the Dominantly Inherited Alzheimer Network Observational Study by using matched cross-sectional and longitudinal cerebrospinal fluid (CSF) and plasma samples from 567 individuals, allowing timely comparative analyses of CSF and blood trajectories across the entire disease spectrum.

Hippocampal volumes in UK Biobank are associated with only in older adults.

Introduction: The hippocampus atrophies with age and is implicated in neurodegenerative disorders including Alzheimer's disease (AD). We examined the interplay between age and apolipoprotein E () genotype on total hippocampal volume.

Methods: Using neuroimaging data from 37,463 UK Biobank participants, we applied linear regression to quantify the association of age and with hippocampal volume and identified the age when volumes of ε2/ε3, ε3/ε4, and ε4/ε4 carriers significantly deviated from ε3/ε3 using generalized additive modeling.

Longitudinal associations between exercise and biomarkers in autosomal dominant Alzheimer's disease.

Introduction: We investigated longitudinal associations between self-reported exercise and Alzheimer's disease (AD)-related biomarkers in individuals with autosomal dominant AD (ADAD) mutations.

Methods: Participants were 308 ADAD mutation carriers aged 39.7 ± 10.

15 Years of Longitudinal Genetic, Clinical, Cognitive, Imaging, and Biochemical Measures in DIAN.

This manuscript describes and summarizes the Dominantly Inherited Alzheimer Network Observational Study (DIAN Obs), highlighting the wealth of longitudinal data, samples, and results from this human cohort study of brain aging and a rare monogenic form of Alzheimer's disease (AD). DIAN Obs is an international collaborative longitudinal study initiated in 2008 with support from the National Institute on Aging (NIA), designed to obtain comprehensive and uniform data on brain biology and function in individuals at risk for autosomal dominant AD (ADAD). ADAD gene mutations in the amyloid protein precursor (), presenilin 1 (), or presenilin 2 () genes are deterministic causes of ADAD, with virtually full penetrance, and a predictable age at symptomatic onset.

γ-Secretase activity, clinical features, and biomarkers of autosomal dominant Alzheimer's disease: cross-sectional and longitudinal analysis of the Dominantly Inherited Alzheimer Network observational study (DIAN-OBS).

Background: Genetic variants that cause autosomal dominant Alzheimer's disease are highly penetrant but vary substantially regarding age at symptom onset (AAO), rates of cognitive decline, and biomarker changes. Most pathogenic variants that cause autosomal dominant Alzheimer's disease are in presenilin 1 (PSEN1), which encodes the catalytic core of γ-secretase, an enzyme complex that is crucial in production of amyloid β. We aimed to investigate whether the heterogeneity in AAO and biomarker trajectories in carriers of PSEN1 pathogenic variants could be predicted on the basis of the effects of individual PSEN1 variants on γ-secretase activity and amyloid β production.

Predicting continuous amyloid PET values with CSF tau phosphorylation occupancies.

Introduction: Cerebrospinal fluid (CSF) tau phosphorylation at multiple sites is associated with cortical amyloid and other pathologic changes in Alzheimer's disease. These relationships can be non-linear. We used an artificial neural network to assess the ability of 10 different CSF tau phosphorylation sites to predict continuous amyloid positron emission tomography (PET) values.