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1.
Cell ; 183(6): 1699-1713.e13, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33188775

RESUMO

To elucidate the role of Tau isoforms and post-translational modification (PTM) stoichiometry in Alzheimer's disease (AD), we generated a high-resolution quantitative proteomics map of 95 PTMs on multiple isoforms of Tau isolated from postmortem human tissue from 49 AD and 42 control subjects. Although Tau PTM maps reveal heterogeneity across subjects, a subset of PTMs display high occupancy and frequency for AD, suggesting importance in disease. Unsupervised analyses indicate that PTMs occur in an ordered manner, leading to Tau aggregation. The processive addition and minimal set of PTMs associated with seeding activity was further defined by analysis of size-fractionated Tau. To summarize, features in the Tau protein critical for disease intervention at different stages of disease are identified, including enrichment of 0N and 4R isoforms, underrepresentation of the C terminus, an increase in negative charge in the proline-rich region (PRR), and a decrease in positive charge in the microtubule binding domain (MBD).


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Processamento de Proteína Pós-Traducional , Proteínas tau/metabolismo , Estudos de Casos e Controles , Estudos de Coortes , Progressão da Doença , Humanos , Análise de Componente Principal , Isoformas de Proteínas/metabolismo
2.
Nature ; 604(7907): 714-722, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35444284

RESUMO

Dementia in Alzheimer's disease progresses alongside neurodegeneration1-4, but the specific events that cause neuronal dysfunction and death remain poorly understood. During normal ageing, neurons progressively accumulate somatic mutations5 at rates similar to those of dividing cells6,7 which suggests that genetic factors, environmental exposures or disease states might influence this accumulation5. Here we analysed single-cell whole-genome sequencing data from 319 neurons from the prefrontal cortex and hippocampus of individuals with Alzheimer's disease and neurotypical control individuals. We found that somatic DNA alterations increase in individuals with Alzheimer's disease, with distinct molecular patterns. Normal neurons accumulate mutations primarily in an age-related pattern (signature A), which closely resembles 'clock-like' mutational signatures that have been previously described in healthy and cancerous cells6-10. In neurons affected by Alzheimer's disease, additional DNA alterations are driven by distinct processes (signature C) that highlight C>A and other specific nucleotide changes. These changes potentially implicate nucleotide oxidation4,11, which we show is increased in Alzheimer's-disease-affected neurons in situ. Expressed genes exhibit signature-specific damage, and mutations show a transcriptional strand bias, which suggests that transcription-coupled nucleotide excision repair has a role in the generation of mutations. The alterations in Alzheimer's disease affect coding exons and are predicted to create dysfunctional genetic knockout cells and proteostatic stress. Our results suggest that known pathogenic mechanisms in Alzheimer's disease may lead to genomic damage to neurons that can progressively impair function. The aberrant accumulation of DNA alterations in neurodegeneration provides insight into the cascade of molecular and cellular events that occurs in the development of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Neurônios , Envelhecimento , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , DNA , Éxons , Genômica , Hipocampo/citologia , Humanos , Taxa de Mutação , Neurônios/patologia , Nucleotídeos , Córtex Pré-Frontal/citologia , Sequenciamento Completo do Genoma
3.
Nature ; 580(7803): 381-385, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32296178

RESUMO

The spread of protein aggregates during disease progression is a common theme underlying many neurodegenerative diseases. The microtubule-associated protein tau has a central role in the pathogenesis of several forms of dementia known as tauopathies-including Alzheimer's disease, frontotemporal dementia and chronic traumatic encephalopathy1. Progression of these diseases is characterized by the sequential spread and deposition of protein aggregates in a predictable pattern that correlates with clinical severity2. This observation and complementary experimental studies3,4 have suggested that tau can spread in a prion-like manner, by passing to naive cells in which it templates misfolding and aggregation. However, although the propagation of tau has been extensively studied, the underlying cellular mechanisms remain poorly understood. Here we show that the low-density lipoprotein receptor-related protein 1 (LRP1) controls the endocytosis of tau and its subsequent spread. Knockdown of LRP1 significantly reduced tau uptake in H4 neuroglioma cells and in induced pluripotent stem cell-derived neurons. The interaction between tau and LRP1 is mediated by lysine residues in the microtubule-binding repeat region of tau. Furthermore, downregulation of LRP1 in an in vivo mouse model of tau spread was found to effectively reduce the propagation of tau between neurons. Our results identify LRP1 as a key regulator of tau spread in the brain, and therefore a potential target for the treatment of diseases that involve tau spread and aggregation.


Assuntos
Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteínas tau/metabolismo , Animais , Linhagem Celular , Endocitose , Feminino , Humanos , Ligantes , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Masculino , Camundongos , Neurônios/metabolismo
4.
J Biol Chem ; 300(6): 107313, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657864

RESUMO

Sortilin-related receptor 1 (SORL1) is an intracellular sorting receptor genetically implicated in Alzheimer's disease (AD) that impacts amyloid precursor protein trafficking. The objective of these studies was to test the hypothesis that SORL1 binds tau, modulates its cellular trafficking and impacts the aggregation of cytoplasmic tau induced by pathological forms of tau. Using surface plasmon resonance measurements, we observed high-affinity binding of tau to SORL1 and the vacuolar protein sorting 10 domain of SORL1. Interestingly, unlike LDL receptor-related protein 1, SORL1 binds tau at both pH 7.4 and pH 5.5, revealing its ability to bind tau at endosomal pH. Immunofluorescence studies confirmed that exogenously added tau colocalized with SORL1 in H4 neuroglioma cells, while overexpression of SORL1 in LDL receptor-related protein 1-deficient Chinese hamster ovary (CHO) cells resulted in a marked increase in the internalization of tau, indicating that SORL1 can bind and mediate the internalization of monomeric forms of tau. We further demonstrated that SORL1 mediates tau seeding when tau RD P301S FRET biosensor cells expressing SORL1 were incubated with high molecular weight forms of tau isolated from the brains of patients with AD. Seeding in H4 neuroglioma cells is significantly reduced when SORL1 is knocked down with siRNA. Finally, we demonstrate that the N1358S mutant of SORL1 significantly increases tau seeding when compared to WT SORL1, identifying for the first time a potential mechanism that connects this specific SORL1 mutation to Alzheimer's disease. Together, these studies identify SORL1 as a receptor that contributes to trafficking and seeding of pathogenic tau.


Assuntos
Cricetulus , Proteínas Relacionadas a Receptor de LDL , Proteínas de Membrana Transportadoras , Proteínas tau , Humanos , Proteínas tau/metabolismo , Proteínas tau/genética , Animais , Células CHO , Proteínas Relacionadas a Receptor de LDL/metabolismo , Proteínas Relacionadas a Receptor de LDL/genética , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Linhagem Celular Tumoral , Ligação Proteica , Transporte Proteico
5.
Ann Neurol ; 95(4): 625-634, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38180638

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder and one of the leading causes of disability worldwide. The apolipoprotein E4 gene (APOE4) is the strongest genetic risk factor for AD. In 2023, the APOE4 National Institute on Aging/Alzheimer's Disease Sequencing Project working group came together to gather data and discuss the question of whether to reduce or increase APOE4 as a therapeutic intervention for AD. It was the unanimous consensus that cumulative data from multiple studies in humans and animal models support that lowering APOE4 should be a target for therapeutic approaches for APOE4 carriers. ANN NEUROL 2024;95:625-634.


Assuntos
Doença de Alzheimer , Animais , Estados Unidos , Humanos , Doença de Alzheimer/terapia , Doença de Alzheimer/tratamento farmacológico , Apolipoproteína E4/genética , Objetivos , National Institute on Aging (U.S.)
6.
Brain ; 147(2): 637-648, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38236720

RESUMO

Aggregation prone molecules, such as tau, form both historically well characterized fibrillar deposits (neurofibrillary tangles) and recently identified phosphate-buffered saline (PBS) extract species called proteopathic seeds. Both can cause normal endogenous tau to undergo templated misfolding. The relationship of these seeds to the fibrils that define tau-related diseases is unknown. We characterized the aqueous extractable and sarkosyl insoluble fibrillar tau species derived from human Alzheimer brain using mass spectrometry and in vitro bioassays. Post-translational modifications (PTMs) including phosphorylation, acetylation and ubiquitination are identified in both preparations. PBS extract seed competent tau can be distinguished from sarkosyl insoluble tau by the presence of overlapping, but less abundant, PTMs and an absence of some PTMs unique to the latter. The presence of ubiquitin and other PTMs on the PBS-extracted tau species correlates with the amount of tau in the seed competent size exclusion fractions, with the bioactivity and with the aggressiveness of clinical disease. These results demonstrate that the PTMs present on bioactive, seed competent PBS extract tau species are closely related to, but distinct from, the PTMs of mature paired helical filaments, consistent with the idea that they are a forme fruste of tau species that ultimately form fibrils.


Assuntos
Doença de Alzheimer , Emaranhados Neurofibrilares , Humanos , Emaranhados Neurofibrilares/metabolismo , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Processamento de Proteína Pós-Traducional , Fosforilação
7.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38275188

RESUMO

Clinical improvement following neurosurgical cerebrospinal fluid shunting for presumed idiopathic normal pressure hydrocephalus is variable. Idiopathic normal pressure hydrocephalus patients may have undetected Alzheimer's disease-related cortical pathology that confounds diagnosis and clinical outcomes. In this study, we sought to determine the utility of cortical tissue immuno-analysis in predicting shunting outcomes in idiopathic normal pressure hydrocephalus patients. We performed a pooled analysis using a systematic review as well as analysis of a new, original patient cohort. Of the 2707 screened studies, 3 studies with a total of 229 idiopathic normal pressure hydrocephalus patients were selected for inclusion in this meta-analysis alongside our original cohort. Pooled statistics of shunting outcomes for the 229 idiopathic normal pressure hydrocephalus patients and our new cohort of 36 idiopathic normal pressure hydrocephalus patients revealed that patients with Aß + pathology were significantly more likely to exhibit shunt nonresponsiveness than patients with negative pathology. Idiopathic normal pressure hydrocephalus patients with Alzheimer's disease -related cortical pathology may be at a higher risk of treatment facing unfavorable outcomes following cerebrospinal fluid shunting. Thus, cortical tissue analysis from living patients may be a useful diagnostic and prognostic adjunct for patients with presumed idiopathic normal pressure hydrocephalus and potentially other neurodegenerative conditions affecting the cerebral cortex.


Assuntos
Doença de Alzheimer , Hidrocefalia de Pressão Normal , Humanos , Hidrocefalia de Pressão Normal/cirurgia , Hidrocefalia de Pressão Normal/patologia , Córtex Cerebral/patologia
8.
Mol Ther ; 32(5): 1373-1386, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38504517

RESUMO

Epidemiological studies show that individuals who carry the relatively uncommon APOE ε2 allele rarely develop Alzheimer disease, and if they do, they have a later age of onset, milder clinical course, and less severe neuropathological findings than people without this allele. The contrast is especially stark when compared with the major genetic risk factor for Alzheimer disease, APOE ε4, which has an age of onset several decades earlier, a more aggressive clinical course and more severe neuropathological findings, especially in terms of the amount of amyloid deposition. Here, we demonstrate that brain exposure to APOE ε2 via a gene therapy approach, which bathes the entire cortical mantle in the gene product after transduction of the ependyma, reduces Aß plaque deposition, neurodegenerative synaptic loss, and, remarkably, reduces microglial activation in an APP/PS1 mouse model despite continued expression of human APOE ε4. This result suggests a promising protective effect of exogenous APOE ε2 and reveals a cell nonautonomous effect of the protein on microglial activation, which we show is similar to plaque-associated microglia in the brain of Alzheimer disease patients who inherit APOE ε2. These data increase the potential that an APOE ε2 therapeutic could be effective in Alzheimer disease, even in individuals born with the risky ε4 allele.


Assuntos
Doença de Alzheimer , Apolipoproteína E2 , Modelos Animais de Doenças , Terapia Genética , Camundongos Transgênicos , Microglia , Placa Amiloide , Animais , Doença de Alzheimer/terapia , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/etiologia , Camundongos , Terapia Genética/métodos , Humanos , Apolipoproteína E2/genética , Apolipoproteína E2/metabolismo , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Microglia/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Doenças Neuroinflamatórias/etiologia , Doenças Neuroinflamatórias/terapia , Doenças Neuroinflamatórias/metabolismo , Peptídeos beta-Amiloides/metabolismo , Biomarcadores
9.
J Neurosci ; 43(24): 4541-4557, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37208174

RESUMO

Vascular endothelial cells play an important role in maintaining brain health, but their contribution to Alzheimer's disease (AD) is obscured by limited understanding of the cellular heterogeneity in normal aged brain and in disease. To address this, we performed single nucleus RNAseq on tissue from 32 human AD and non-AD donors (19 female, 13 male) each with five cortical regions: entorhinal cortex, inferior temporal gyrus, prefrontal cortex, visual association cortex, and primary visual cortex. Analysis of 51,586 endothelial cells revealed unique gene expression patterns across the five regions in non-AD donors. Alzheimer's brain endothelial cells were characterized by upregulated protein folding genes and distinct transcriptomic differences in response to amyloid ß plaques and cerebral amyloid angiopathy. This dataset demonstrates previously unrecognized regional heterogeneity in the endothelial cell transcriptome in both aged non-AD and AD brain.SIGNIFICANCE STATEMENT In this work, we show that vascular endothelial cells collected from five different brain regions display surprising variability in gene expression. In the presence of Alzheimer's disease pathology, endothelial cell gene expression is dramatically altered with clear differences in regional and temporal changes. These findings help explain why certain brain regions appear to differ in susceptibility to disease-related vascular remodeling events that may impact blood flow.


Assuntos
Doença de Alzheimer , Angiopatia Amiloide Cerebral , Masculino , Feminino , Humanos , Idoso , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Células Endoteliais/metabolismo , Encéfalo/metabolismo , Angiopatia Amiloide Cerebral/genética , Placa Amiloide/patologia , Núcleo Solitário/metabolismo , Córtex Entorrinal/metabolismo
10.
Biochemistry ; 63(2): 194-201, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38154792

RESUMO

The protein tau misfolds into disease-specific fibrillar structures in more than 20 neurodegenerative diseases collectively referred to as tauopathies. To understand and prevent disease-specific mechanisms of filament formation, in vitro models for aggregation that robustly yield these different end point structures will be necessary. Here, we used cryo-electron microscopy (cryo-EM) to reconstruct fibril polymorphs taken on by residues 297-391 of tau under conditions previously shown to give rise to the core structure found in Alzheimer's disease (AD). While we were able to reconstitute the AD tau core fold, the proportion of these paired helical filaments (PHFs) was highly variable, and a majority of filaments were composed of PHFs with an additional identical C-shaped protofilament attached near the PHF interface, termed triple helical filaments (THFs). Since the impact of filament layer quaternary structure on the biological properties of tau and other amyloid filaments is not known, the applications for samples of this morphology are presently uncertain. We further demonstrate the variation in the proportion of PHFs and PHF-like fibrils compared to other morphologies as a function of shaking time and AD polymorph-favoring cofactor concentration. This variation in polymorph abundance, even under identical experimental conditions, highlights the variation that can arise both within a lab and in different laboratory settings when reconstituting specific fibril polymorphs in vitro.


Assuntos
Doença de Alzheimer , Proteínas tau , Humanos , Doença de Alzheimer/metabolismo , Microscopia Crioeletrônica , Emaranhados Neurofibrilares/química , Proteínas tau/química , Proteínas tau/genética , Estrutura Quaternária de Proteína
11.
Acta Neuropathol ; 147(1): 66, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568475

RESUMO

Reactive astrogliosis accompanies the two neuropathological hallmarks of Alzheimer's disease (AD)-Aß plaques and neurofibrillary tangles-and parallels neurodegeneration in AD and AD-related dementias (ADRD). Thus, there is growing interest in developing imaging and fluid biomarkers of reactive astrogliosis for AD/ADRD diagnosis and prognostication. Monoamine oxidase-B (MAO-B) is emerging as a target for PET imaging radiotracers of reactive astrogliosis. However, a thorough characterization of MAO-B expression in postmortem control and AD/ADRD brains is lacking. We sought to: (1) identify the primary cell type(s) expressing MAO-B in control and AD brains; (2) quantify MAO-B immunoreactivity in multiple brain regions of control and AD donors as a proxy for PET radiotracer uptake; (3) correlate MAO-B level with local AD neuropathological changes, reactive glia, and cortical atrophy; (4) determine whether the MAOB rs1799836 SNP genotype impacts MAO-B expression level; (5) compare MAO-B immunoreactivity across AD/ADRD, including Lewy body diseases (LBD) and frontotemporal lobar degenerations with tau (FTLD-Tau) and TDP-43 (FTLD-TDP). We found that MAO-B is mainly expressed by subpial and perivascular cortical astrocytes as well as by fibrous white matter astrocytes in control brains, whereas in AD brains, MAO-B is significantly upregulated by both cortical reactive astrocytes and white matter astrocytes across temporal, frontal, and occipital lobes. By contrast, MAO-B expression level was unchanged and lowest in cerebellum. Cortical MAO-B expression was independently associated with cortical atrophy and local measures of reactive astrocytes and microglia, and significantly increased in reactive astrocytes surrounding Thioflavin-S+ dense-core Aß plaques. MAO-B expression was not affected by the MAOB rs1799836 SNP genotype. MAO-B expression was also significantly increased in the frontal cortex and white matter of donors with corticobasal degeneration, Pick's disease, and FTLD-TDP, but not in LBD or progressive supranuclear palsy. These findings support ongoing efforts to develop MAO-B-based PET radiotracers to image reactive astrogliosis in AD/ADRD.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Doença por Corpos de Lewy , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Gliose , Biomarcadores , Atrofia
12.
Acta Neuropathol ; 147(1): 101, 2024 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884806

RESUMO

Insoluble pathogenic proteins accumulate along blood vessels in conditions of cerebral amyloid angiopathy (CAA), exerting a toxic effect on vascular cells and impacting cerebral homeostasis. In this work, we provide new evidence from three-dimensional human brain histology that tau protein, the main component of neurofibrillary tangles, can similarly accumulate along brain vascular segments. We quantitatively assessed n = 6 Alzheimer's disease (AD), and n = 6 normal aging control brains and saw that tau-positive blood vessel segments were present in all AD cases. Tau-positive vessels are enriched for tau at levels higher than the surrounding tissue and appear to affect arterioles across cortical layers (I-V). Further, vessels isolated from these AD tissues were enriched for N-terminal tau and tau phosphorylated at T181 and T217. Importantly, tau-positive vessels are associated with local areas of increased tau neurofibrillary tangles. This suggests that accumulation of tau around blood vessels may reflect a local clearance failure. In sum, these data indicate that tau, like amyloid beta, accumulates along blood vessels and may exert a significant influence on vasculature in the setting of AD.


Assuntos
Doença de Alzheimer , Encéfalo , Emaranhados Neurofibrilares , Proteínas tau , Humanos , Doença de Alzheimer/patologia , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Emaranhados Neurofibrilares/patologia , Emaranhados Neurofibrilares/metabolismo , Encéfalo/patologia , Encéfalo/metabolismo , Feminino , Masculino , Idoso , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Fosforilação
13.
Acta Neuropathol ; 147(1): 56, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478117

RESUMO

The stimulator of interferon genes (STING) pathway has been implicated in neurodegenerative diseases, including Parkinson's disease and amyotrophic lateral sclerosis (ALS). While prior studies have focused on STING within immune cells, little is known about STING within neurons. Here, we document neuronal activation of the STING pathway in human postmortem cortical and spinal motor neurons from individuals affected by familial or sporadic ALS. This process takes place selectively in the most vulnerable cortical and spinal motor neurons but not in neurons that are less affected by the disease. Concordant STING activation in layer V cortical motor neurons occurs in a mouse model of C9orf72 repeat-associated ALS and frontotemporal dementia (FTD). To establish that STING activation occurs in a neuron-autonomous manner, we demonstrate the integrity of the STING signaling pathway, including both upstream activators and downstream innate immune response effectors, in dissociated mouse cortical neurons and neurons derived from control human induced pluripotent stem cells (iPSCs). Human iPSC-derived neurons harboring different familial ALS-causing mutations exhibit increased STING signaling with DNA damage as a main driver. The elevated downstream inflammatory markers present in ALS iPSC-derived neurons can be suppressed with a STING inhibitor. Our results reveal an immunophenotype that consists of innate immune signaling driven by the STING pathway and occurs specifically within vulnerable neurons in ALS/FTD.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Células-Tronco Pluripotentes Induzidas , Doença de Pick , Animais , Humanos , Camundongos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Proteína C9orf72/genética , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios Motores/metabolismo
14.
Acta Neuropathol ; 147(1): 65, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557897

RESUMO

Human microglia are critically involved in Alzheimer's disease (AD) progression, as shown by genetic and molecular studies. However, their role in tau pathology progression in human brain has not been well described. Here, we characterized 32 human donors along progression of AD pathology, both in time-from early to late pathology-and in space-from entorhinal cortex (EC), inferior temporal gyrus (ITG), prefrontal cortex (PFC) to visual cortex (V2 and V1)-with biochemistry, immunohistochemistry, and single nuclei-RNA-sequencing, profiling a total of 337,512 brain myeloid cells, including microglia. While the majority of microglia are similar across brain regions, we identified a specific subset unique to EC which may contribute to the early tau pathology present in this region. We calculated conversion of microglia subtypes to diseased states and compared conversion patterns to those from AD animal models. Targeting genes implicated in this conversion, or their upstream/downstream pathways, could halt gene programs initiated by early tau progression. We used expression patterns of early tau progression to identify genes whose expression is reversed along spreading of spatial tau pathology (EC > ITG > PFC > V2 > V1) and identified their potential involvement in microglia subtype conversion to a diseased state. This study provides a data resource that builds on our knowledge of myeloid cell contribution to AD by defining the heterogeneity of microglia and brain macrophages during both temporal and regional pathology aspects of AD progression at an unprecedented resolution.


Assuntos
Doença de Alzheimer , Animais , Humanos , Doença de Alzheimer/patologia , Proteínas tau/genética , Proteínas tau/metabolismo , Transcriptoma , Encéfalo/patologia , Células Mieloides/patologia , Microglia/patologia , Peptídeos beta-Amiloides/metabolismo
15.
Acta Neuropathol ; 147(1): 9, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175301

RESUMO

Nuclear clearance and cytoplasmic accumulations of the RNA-binding protein TDP-43 are pathological hallmarks in almost all patients with amyotrophic lateral sclerosis (ALS) and up to 50% of patients with frontotemporal dementia (FTD) and Alzheimer's disease. In Alzheimer's disease, TDP-43 pathology is predominantly observed in the limbic system and correlates with cognitive decline and reduced hippocampal volume. Disruption of nuclear TDP-43 function leads to abnormal RNA splicing and incorporation of erroneous cryptic exons in numerous transcripts including Stathmin-2 (STMN2, also known as SCG10) and UNC13A, recently reported in tissues from patients with ALS and FTD. Here, we identify both STMN2 and UNC13A cryptic exons in Alzheimer's disease patients, that correlate with TDP-43 pathology burden, but not with amyloid-ß or tau deposits. We also demonstrate that processing of the STMN2 pre-mRNA is more sensitive to TDP-43 loss of function than UNC13A. In addition, full-length RNAs encoding STMN2 and UNC13A are suppressed in large RNA-seq datasets generated from Alzheimer's disease post-mortem brain tissue. Collectively, these results open exciting new avenues to use STMN2 and UNC13A as potential therapeutic targets in a broad range of neurodegenerative conditions with TDP-43 proteinopathy including Alzheimer's disease.


Assuntos
Doença de Alzheimer , Esclerose Lateral Amiotrófica , Demência Frontotemporal , Doença de Pick , Humanos , Doença de Alzheimer/genética , Proteínas de Ligação a DNA/genética , Splicing de RNA , RNA Mensageiro/genética , Estatmina/genética
16.
Nat Rev Neurosci ; 20(2): 94-108, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30643230

RESUMO

The symptoms of Alzheimer disease reflect a loss of neural circuit integrity in the brain, but neurons do not work in isolation. Emerging evidence suggests that the intricate balance of interactions between neurons, astrocytes, microglia and vascular cells required for healthy brain function becomes perturbed during the disease, with early changes likely protecting neural circuits from damage, followed later by harmful effects when the balance cannot be restored. Moving beyond a neuronal focus to understand the complex cellular interactions in Alzheimer disease and how these change throughout the course of the disease may provide important insight into developing effective therapeutics.


Assuntos
Doença de Alzheimer/patologia , Neurônios/patologia , Doença de Alzheimer/terapia , Animais , Astrócitos/patologia , Encéfalo/patologia , Comunicação Celular/fisiologia , Humanos , Microglia/patologia
17.
Cereb Cortex ; 33(23): 11400-11407, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-37814356

RESUMO

Idiopathic normal pressure hydrocephalus is a disorder of unknown pathophysiology whose diagnosis is paradoxically made by a positive response to its proposed treatment with cerebrospinal fluid diversion. There are currently no idiopathic normal pressure hydrocephalus disease genes or biomarkers. A systematic analysis of familial idiopathic normal pressure hydrocephalus could aid in clinical diagnosis, prognosis, and treatment stratification, and elucidate disease patho-etiology. In this 2-part analysis, we review literature-based evidence for inheritance of idiopathic normal pressure hydrocephalus in 22 pedigrees, and then present a novel case series of 8 familial idiopathic normal pressure hydrocephalus patients. For the case series, demographics, familial history, pre- and post-operative symptoms, and cortical pathology were collected. All novel familial idiopathic normal pressure hydrocephalus patients exhibited improvement following shunt treatment and absence of neurodegenerative cortical pathology (amyloid-beta and hyperphosphorylated tau), in contrast to many sporadic cases of idiopathic normal pressure hydrocephalus with variable clinical responses. Analysis of the 30 total familial idiopathic normal pressure hydrocephalus cases reported herein is highly suggestive of an autosomal dominant mechanism of inheritance. This largest-ever presentation of multiply affected idiopathic normal pressure hydrocephalus pedigrees provides strong evidence for Mendelian inheritance and autosomal dominant transmission of an idiopathic normal pressure hydrocephalus trait in a subset of patients that positively respond to shunting and lack neurodegenerative pathology. Genomic investigation of these families may identify the first bona fide idiopathic normal pressure hydrocephalus disease gene.


Assuntos
Hidrocefalia de Pressão Normal , Humanos , Hidrocefalia de Pressão Normal/genética , Hidrocefalia de Pressão Normal/cirurgia , Hidrocefalia de Pressão Normal/líquido cefalorraquidiano , Prognóstico , Biomarcadores/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano
18.
Alzheimers Dement ; 20(10): 7384-7394, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39240044

RESUMO

Biological and clinical heterogeneity is a major challenge in research for developing new treatments for Alzheimer's disease (AD). AD may be defined by its amyloid beta and tau pathologies, but we recognize that mixed pathologies are common, and that diverse genetics, central nervous system (CNS) and systemic pathophysiological processes, and environmental/experiential factors contribute to AD's diverse clinical and neuropathological features. All these factors are rational targets for therapeutic development; indeed, there are hundreds of candidate pharmacological, dietary, neurostimulation, and lifestyle interventions that show benefits in homogeneous laboratory models. Conventional clinical trial designs accommodate heterogeneity poorly, and this may be one reason that progress in translating candidate interventions has been so difficult. We review the challenges of AD's heterogeneity for the clinical trials enterprise. We then discuss how advances in repeatable biomarkers and digital phenotyping enable novel "single-case" and adaptive trial designs to accelerate therapeutics development, moving us closer to personalized research and medicine for AD. HIGHLIGHTS: Alzheimer's disease is diverse in its clinical features, course, risks, and biology. Typical randomized controlled trials are exclusive and necessarily large to attain arm comparability with broad outcomes. Repeated blood biomarkers and digital tracking can improve outcome measure precision and sensitivity. This enables the use of novel "single-case" and adaptive trial designs for inclusivity, rigor, and efficiency.


Assuntos
Doença de Alzheimer , Medicina de Precisão , Doença de Alzheimer/terapia , Doença de Alzheimer/genética , Humanos , Medicina de Precisão/métodos , Biomarcadores/sangue , Ensaios Clínicos como Assunto
19.
Alzheimers Dement ; 20(1): 74-90, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37461318

RESUMO

INTRODUCTION: Omics studies have revealed that various brain cell types undergo profound molecular changes in Alzheimer's disease (AD) but the spatial relationships with plaques and tangles and APOE-linked differences remain unclear. METHODS: We performed laser capture microdissection of amyloid beta (Aß) plaques, the 50 µm halo around them, tangles with the 50 µm halo around them, and areas distant (> 50 µm) from plaques and tangles in the temporal cortex of AD and control donors, followed by RNA-sequencing. RESULTS: Aß plaques exhibited upregulated microglial (neuroinflammation/phagocytosis) and downregulated neuronal (neurotransmission/energy metabolism) genes, whereas tangles had mostly downregulated neuronal genes. Aß plaques had more differentially expressed genes than tangles. We identified a gradient Aß plaque > peri-plaque > tangle > distant for these changes. AD APOE ε4 homozygotes had greater changes than APOE ε3 across locations, especially within Aß plaques. DISCUSSION: Transcriptomic changes in AD consist primarily of neuroinflammation and neuronal dysfunction, are spatially associated mainly with Aß plaques, and are exacerbated by the APOE ε4 allele.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Emaranhados Neurofibrilares , Apolipoproteína E4/genética , Doenças Neuroinflamatórias , Encéfalo/metabolismo , Transcriptoma , Placa Amiloide/metabolismo , Perfilação da Expressão Gênica
20.
Alzheimers Dement ; 20(3): 2298-2308, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38265159

RESUMO

Despite its high prevalence among dementias, Lewy body dementia (LBD) remains poorly understood with a limited, albeit growing, evidence base. The public-health burden that LBD imposes is worsened by overlapping pathologies, which contribute to misdiagnosis, and lack of treatments. For this report, we gathered and analyzed public-domain information on advocacy, funding, research outputs, and the therapeutic pipeline to identify gaps in each of these key elements. To further understand the current gaps, we also conducted interviews with leading experts in regulatory/governmental agencies, LBD advocacy, academic research, and biopharmaceutical research, as well as with funding sources. We identified wide gaps across the entire landscape, the most critical being in research. Many of the experts participated in a workshop to discuss the prioritization of research areas with a view to accelerating therapeutic development and improving patient care. This white paper outlines the opportunities for bridging the major LBD gaps and creates the framework for collaboration in that endeavor. HIGHLIGHTS: A group representing academia, government, industry, and consulting expertise was convened to discuss current progress in Dementia with Lewy Body care and research. Consideration of expert opinion,natural language processing of the literature as well as publicly available data bases, and Delphi inspired discussion led to a proposed consensus document of priorities for the field.


Assuntos
Doença por Corpos de Lewy , Humanos , Doença por Corpos de Lewy/diagnóstico , Doença por Corpos de Lewy/terapia
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