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1.
JAMA ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739396

RESUMO

Importance: Identification of individuals at high risk for atherosclerotic cardiovascular disease within the population is important to inform primary prevention strategies. Objective: To evaluate the prognostic value of routinely available cardiovascular biomarkers when added to established risk factors. Design, Setting, and Participants: Individual-level analysis including data on cardiovascular biomarkers from 28 general population-based cohorts from 12 countries and 4 continents with assessments by participant age. The median follow-up was 11.8 years. Exposure: Measurement of high-sensitivity cardiac troponin I, high-sensitivity cardiac troponin T, N-terminal pro-B-type natriuretic peptide, B-type natriuretic peptide, or high-sensitivity C-reactive protein. Main Outcomes and Measures: The primary outcome was incident atherosclerotic cardiovascular disease, which included all fatal and nonfatal events. The secondary outcomes were all-cause mortality, heart failure, ischemic stroke, and myocardial infarction. Subdistribution hazard ratios (HRs) for the association of biomarkers and outcomes were calculated after adjustment for established risk factors. The additional predictive value of the biomarkers was assessed using the C statistic and reclassification analyses. Results: The analyses included 164 054 individuals (median age, 53.1 years [IQR, 42.7-62.9 years] and 52.4% were women). There were 17 211 incident atherosclerotic cardiovascular disease events. All biomarkers were significantly associated with incident atherosclerotic cardiovascular disease (subdistribution HR per 1-SD change, 1.13 [95% CI, 1.11-1.16] for high-sensitivity cardiac troponin I; 1.18 [95% CI, 1.12-1.23] for high-sensitivity cardiac troponin T; 1.21 [95% CI, 1.18-1.24] for N-terminal pro-B-type natriuretic peptide; 1.14 [95% CI, 1.08-1.22] for B-type natriuretic peptide; and 1.14 [95% CI, 1.12-1.16] for high-sensitivity C-reactive protein) and all secondary outcomes. The addition of each single biomarker to a model that included established risk factors improved the C statistic. For 10-year incident atherosclerotic cardiovascular disease in younger people (aged <65 years), the combination of high-sensitivity cardiac troponin I, N-terminal pro-B-type natriuretic peptide, and high-sensitivity C-reactive protein resulted in a C statistic improvement from 0.812 (95% CI, 0.8021-0.8208) to 0.8194 (95% CI, 0.8089-0.8277). The combination of these biomarkers also improved reclassification compared with the conventional model. Improvements in risk prediction were most pronounced for the secondary outcomes of heart failure and all-cause mortality. The incremental value of biomarkers was greater in people aged 65 years or older vs younger people. Conclusions and Relevance: Cardiovascular biomarkers were strongly associated with fatal and nonfatal cardiovascular events and mortality. The addition of biomarkers to established risk factors led to only a small improvement in risk prediction metrics for atherosclerotic cardiovascular disease, but was more favorable for heart failure and mortality.

2.
Nat Genet ; 56(5): 778-791, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38689001

RESUMO

Hypertension affects more than one billion people worldwide. Here we identify 113 novel loci, reporting a total of 2,103 independent genetic signals (P < 5 × 10-8) from the largest single-stage blood pressure (BP) genome-wide association study to date (n = 1,028,980 European individuals). These associations explain more than 60% of single nucleotide polymorphism-based BP heritability. Comparing top versus bottom deciles of polygenic risk scores (PRSs) reveals clinically meaningful differences in BP (16.9 mmHg systolic BP, 95% CI, 15.5-18.2 mmHg, P = 2.22 × 10-126) and more than a sevenfold higher odds of hypertension risk (odds ratio, 7.33; 95% CI, 5.54-9.70; P = 4.13 × 10-44) in an independent dataset. Adding PRS into hypertension-prediction models increased the area under the receiver operating characteristic curve (AUROC) from 0.791 (95% CI, 0.781-0.801) to 0.826 (95% CI, 0.817-0.836, ∆AUROC, 0.035, P = 1.98 × 10-34). We compare the 2,103 loci results in non-European ancestries and show significant PRS associations in a large African-American sample. Secondary analyses implicate 500 genes previously unreported for BP. Our study highlights the role of increasingly large genomic studies for precision health research.


Assuntos
Pressão Sanguínea , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Hipertensão , Herança Multifatorial , Polimorfismo de Nucleotídeo Único , Feminino , Humanos , Masculino , Pressão Sanguínea/genética , Estratificação de Risco Genético , Hipertensão/genética , Fatores de Risco
3.
Acta Neuropathol Commun ; 12(1): 22, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317196

RESUMO

Deposition of amyloid beta (Aß) into plaques is a major hallmark of Alzheimer's disease (AD). Different amyloid precursor protein (APP) mutations cause early-onset AD by altering the production or aggregation properties of Aß. We recently identified the Uppsala APP mutation (APPUpp), which causes Aß pathology by a triple mechanism: increased ß-secretase and altered α-secretase APP cleavage, leading to increased formation of a unique Aß conformer that rapidly aggregates and deposits in the brain. The aim of this study was to further explore the effects of APPUpp in a transgenic mouse model (tg-UppSwe), expressing human APP with the APPUpp mutation together with the APPSwe mutation. Aß pathology was studied in tg-UppSwe brains at different ages, using ELISA and immunohistochemistry. In vivo PET imaging with three different PET radioligands was conducted in aged tg-UppSwe mice and two other mouse models; tg-ArcSwe and tg-Swe. Finally, glial responses to Aß pathology were studied in cell culture models and mouse brain tissue, using ELISA and immunohistochemistry. Tg-UppSwe mice displayed increased ß-secretase cleavage and suppressed α-secretase cleavage, resulting in AßUpp42 dominated diffuse plaque pathology appearing from the age of 5-6 months. The γ-secretase cleavage was not affected. Contrary to tg-ArcSwe and tg-Swe mice, tg-UppSwe mice were [11C]PiB-PET negative. Antibody-based PET with the 3D6 ligand visualized Aß pathology in all models, whereas the Aß protofibril selective mAb158 ligand did not give any signals in tg-UppSwe mice. Moreover, unlike the other two models, tg-UppSwe mice displayed a very faint glial response to the Aß pathology. The tg-UppSwe mouse model thus recapitulates several pathological features of the Uppsala APP mutation carriers. The presumed unique structural features of AßUpp42 aggregates were found to affect their interaction with anti-Aß antibodies and profoundly modify the Aß-mediated glial response, which may be important aspects to consider for further development of AD therapies.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Animais , Humanos , Camundongos , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Gliose/patologia , Ligantes , Camundongos Transgênicos
5.
BMC Geriatr ; 23(1): 535, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660032

RESUMO

BACKGROUND: While assessment tools can increase the detection of cognitive impairment, there is currently insufficient evidence regarding clinical outcomes based on screening for cognitive impairment in older adults. METHODS: The study purpose was to investigate whether Timed Up and Go dual-task test (TUGdt) results, based on TUG combined with two different verbal tasks (name different animals, TUGdt-NA, and recite months in reverse order, TUGdt-MB), predicted dementia incidence over a period of five years among patients (N = 186, mean = 70.7 years; 45.7% female) diagnosed with Subjective Cognitive Impairment (SCI) and Mild Cognitive Impairment (MCI) following assessment at two memory clinics. Associations between TUG parameters and dementia incidence were examined in Cox regression models. RESULTS: During follow-up time (median (range) 3.7 (0.1-6.1) years) 98 participants converted to dementia. Novel findings indicated that the TUGdt parameter words/time, after adjustment for age, gender, and education, can be used for the prediction of conversion to dementia in participants with SCI or MCI over a period of five years. Among the TUG-related parameters investigated, words/time showed the best predictive capacity, while time scores of TUG and TUGdt as well as TUGdt cost did not produce significant predictive results. Results further showed that the step parameter step length during TUGdt predicts conversion to dementia before adjustment for age, gender, and education. Optimal TUGdt cutoffs for predicting dementia at 2- and 4-year follow-up based on words/time were calculated. The sensitivity of the TUGdt cutoffs was high at 2-year follow-up: TUGdt-NA words/time, 0.79; TUGdt-MB words/time, 0.71; reducing respectively to 0.64 and 0.65 at 4-year follow-up. CONCLUSIONS: TUGdt words/time parameters have potential as cost-efficient tools for conversion-to-dementia risk assessment, useful for research and clinical purposes. These parameters may be able to bridge the gap of insufficient evidence for such clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05893524: https://www. CLINICALTRIALS: gov/study/NCT05893524?id=NCT05893524&rank=1 .


Assuntos
Disfunção Cognitiva , Demência , Memória Episódica , Feminino , Humanos , Animais , Masculino , Escolaridade , Instituições de Assistência Ambulatorial , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Demência/diagnóstico , Demência/epidemiologia
6.
Proc Natl Acad Sci U S A ; 120(36): e2302720120, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37643212

RESUMO

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson's disease (PD) and Alzheimer's disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aß42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues.


Assuntos
Doença de Alzheimer , Cadeias HLA-DRB1 , Doença de Parkinson , Humanos , Doença de Alzheimer/genética , Antígenos de Histocompatibilidade , Antígenos HLA , Cadeias HLA-DRB1/genética , Doença de Parkinson/genética
7.
J Aging Phys Act ; 31(5): 823-832, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37019438

RESUMO

The Timed Up-and-Go (TUG) test has been combined with different verbal/cognitive tasks (i.e., TUG dual task [TUGdt]) as a form of motor-cognitive testing. However, it is still unclear how different TUGdt conditions affect gait among older adults. Thirty community-dwelling older adults, with mean age of 73 years, participated in the study. Data were collected using marker-free video recordings. Gait parameters were extracted using a semiautomatic deep learning system. Comparisons of execution time and gait parameter outcomes were made under TUG and three types of TUGdt test conditions: TUGdt-naming animals, TUGdt-months backwards, and TUGdt-serial 7s. Statistical analyses were based on mean values of the gait parameters for each participant and TUG condition, including TUGdt gait cost, that is, the relative difference between TUGdt and TUG. All the investigated TUGdt conditions resulted in varying degrees of gait parameter changes. Under TUGdt conditions, participants took shorter and slower steps, with TUGdt-serial 7s causing the largest interference.


Assuntos
Marcha , Vida Independente , Humanos
8.
J Alzheimers Dis ; 90(4): 1601-1614, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36314207

RESUMO

BACKGROUND: There are more than 300 presenilin-1 (PSEN1) mutations identified but a thorough postmortem neuropathological assessment of the mutation carriers is seldom performed. OBJECTIVE: To assess neuropathological changes (NC) in a 73-year-old subject with the novel PSEN1 G206R mutation suffering from cognitive decline in over 20 years. To compare these findings with an age- and gender-matched subject with sporadic Alzheimer's disease (sAD). METHODS: The brains were assessed macro- and microscopically and the proteinopathies were staged according to current recommendations. RESULTS: The AD neuropathological change (ADNC) was more extensive in the mutation carrier, although both individuals reached a high level of ADNC. The transactive DNA binding protein 43 pathology was at the end-stage in the index subject, a finding not previously described in familial AD. This pathology was moderate in the sAD subject. The PSEN1 G206R subject displayed full-blown alpha-synuclein pathology, while this proteinopathy was absent in the sAD case. Additionally, the mutation carrier displayed pronounced neuroinflammation, not previously described in association with PSEN1 mutations. CONCLUSION: Our findings are exceptional, as the PSEN1 G206R subject displayed an end-stage pathology of every common proteinopathy. It is unclear whether the observed alterations are caused by the mutation or are related to a cross-seeding mechanisms. The pronounced neuroinflammation in the index patient can be reactive to the extensive NC or a contributing factor to the proteinopathies. Thorough postmortem neuropathological and genetic assessment of subjects with familial AD is warranted, for further understanding of a dementing illness.


Assuntos
Doença de Alzheimer , Humanos , Idoso , Presenilina-1/genética , Presenilina-1/metabolismo , Doença de Alzheimer/patologia , Encéfalo/patologia , Mutação/genética
9.
JAMA Neurol ; 79(7): 652-663, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35639372

RESUMO

Importance: The APOE ε2 and APOE ε4 alleles are the strongest protective and risk-increasing, respectively, genetic variants for late-onset Alzheimer disease (AD). However, the mechanisms linking APOE to AD-particularly the apoE protein's role in AD pathogenesis and how this is affected by APOE variants-remain poorly understood. Identifying missense variants in addition to APOE ε2 and APOE ε4 could provide critical new insights, but given the low frequency of additional missense variants, AD genetic cohorts have previously been too small to interrogate this question robustly. Objective: To determine whether rare missense variants on APOE are associated with AD risk. Design, Setting, and Participants: Association with case-control status was tested in a sequenced discovery sample (stage 1) and followed up in several microarray imputed cohorts as well as the UK Biobank whole-exome sequencing resource using a proxy-AD phenotype (stages 2 and 3). This study combined case-control, family-based, population-based, and longitudinal AD-related cohorts that recruited referred and volunteer participants. Stage 1 included 37 409 nonunique participants of European or admixed European ancestry, with 11 868 individuals with AD and 11 934 controls passing analysis inclusion criteria. In stages 2 and 3, 475 473 participants were considered across 8 cohorts, of which 84 513 individuals with AD and proxy-AD and 328 372 controls passed inclusion criteria. Selection criteria were cohort specific, and this study was performed a posteriori on individuals who were genotyped. Among the available genotypes, 76 195 were excluded. All data were retrieved between September 2015 and November 2021 and analyzed between April and November 2021. Main Outcomes and Measures: In primary analyses, the AD risk associated with each missense variant was estimated, as appropriate, with either linear mixed-model regression or logistic regression. In secondary analyses, associations were estimated with age at onset using linear mixed-model regression and risk of conversion to AD using competing-risk regression. Results: A total of 544 384 participants were analyzed in the primary case-control analysis; 312 476 (57.4%) were female, and the mean (SD; range) age was 64.9 (15.2; 40-110) years. Two missense variants were associated with a 2-fold to 3-fold decreased AD risk: APOE ε4 (R251G) (odds ratio, 0.44; 95% CI, 0.33-0.59; P = 4.7 × 10-8) and APOE ε3 (V236E) (odds ratio, 0.37; 95% CI, 0.25-0.56; P = 1.9 × 10-6). Additionally, the cumulative incidence of AD in carriers of these variants was found to grow more slowly with age compared with noncarriers. Conclusions and Relevance: In this genetic association study, a novel variant associated with AD was identified: R251G always coinherited with ε4 on the APOE gene, which mitigates the ε4-associated AD risk. The protective effect of the V236E variant, which is always coinherited with ε3 on the APOE gene, was also confirmed. The location of these variants confirms that the carboxyl-terminal portion of apoE plays an important role in AD pathogenesis. The large risk reductions reported here suggest that protein chemistry and functional assays of these variants should be pursued, as they have the potential to guide drug development targeting APOE.


Assuntos
Doença de Alzheimer , Idade de Início , Alelos , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Apolipoproteína E2/genética , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Feminino , Genótipo , Humanos , Masculino
10.
Mol Ther Nucleic Acids ; 28: 450-461, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35505961

RESUMO

Presenilin 1 (PS1) is a central component of γ-secretase, an enzymatic complex involved in the generation of the amyloid-ß (Aß) peptide that deposits as plaques in the Alzheimer's disease (AD) brain. The M146L mutation in the PS1 gene (PSEN1) leads to an autosomal dominant form of early-onset AD by promoting a relative increase in the generation of the more aggregation-prone Aß42. This change is evident not only in the brain but also in peripheral cells of mutation carriers. In this study we used the CRISPR-Cas9 system from Streptococcus pyogenes to selectively disrupt the PSEN1 M146L allele in human fibroblasts. A disruption of more than 50% of mutant alleles was observed in all CRISPR-Cas9-treated samples, resulting in reduced extracellular Aß42/40 ratios. Fluorescence resonance energy transfer-based conformation and western blot analyses indicated that CRISPR-Cas9 treatment also affects the overall PS1 conformation and reduces PS1 levels. Moreover, our guide RNA did not lead to any detectable editing at the highest-ranking candidate off-target sites identified by ONE-seq and CIRCLE-seq. Overall, our data support the effectiveness of CRISPR-Cas9 in selectively targeting the PSEN1 M146L allele and counteracting the AD-associated phenotype. We believe that this system could be developed into a therapeutic strategy for patients with this and other dominant mutations leading to early-onset AD.

11.
Nat Genet ; 54(4): 412-436, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379992

RESUMO

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.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Disfunção Cognitiva/psicologia , Estudo de Associação Genômica Ampla , Humanos , Proteínas tau/genética
13.
BMC Genomics ; 23(1): 99, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35120450

RESUMO

BACKGROUND: Most dementia disorders have a clear genetic background and a number of disease genes have been identified. Mutations in the tau gene (MAPT) lead to frontotemporal dementia (FTD), whereas mutations in the genes for the amyloid-ß precursor protein (APP) and the presenilins (PSEN1, PSEN2) cause early-onset, dominantly inherited forms of Alzheimer's disease (AD). Even if mutations causing Mendelian forms of these diseases are uncommon, elucidation of the pathogenic effects of such mutations have proven important for understanding the pathogenic processes. Here, we performed a screen to identify novel pathogenic mutations in known disease genes among patients undergoing dementia investigation. RESULTS: Using targeted exome sequencing we have screened all coding exons in eleven known dementia genes (PSEN1, PSEN2, APP, MAPT, APOE, GRN, TARDBP, CHMP2B, TREM2, VCP and FUS) in 102 patients with AD, FTD, other dementia diagnoses or mild cognitive impairment. We found three AD patients with two previously identified pathogenic mutations in PSEN1 (Pro264Leu and Met146Val). In this screen, we also identified the recently reported APP mutation in two siblings with AD. This mutation, named the Uppsala mutation, consists of a six amino acid intra-amyloid ß deletion. In addition, we found several potentially pathogenic mutations in PSEN2, FUS, MAPT, GRN and APOE. Finally, APOE ε4 was prevalent in this patient group with an allele frequency of 54%. CONCLUSIONS: Among the 102 screened patients, we found two disease causing mutations in PSEN1 and one in APP, as well as several potentially pathogenic mutations in other genes related to neurodegenerative disorders. Apart from giving important information to the clinical investigation, the identification of disease mutations can contribute to an increased understanding of disease mechanisms.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Demência Frontotemporal/genética , Humanos , Glicoproteínas de Membrana , Mutação , Presenilina-1/genética , Presenilina-2/genética , Receptores Imunológicos
14.
Gait Posture ; 90: 489-495, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34628196

RESUMO

BACKGROUND: We study dual-task performance with marker-free video recordings of Timed Up-and-Go tests (TUG) and TUG combined with a cognitive/verbal task (TUG dual-task, TUGdt). RESEARCH QUESTION: Can gait parameters be accurately estimated from video-recorded TUG tests by a new semi-automatic method aided by a technique for human 2D pose estimation based on deep learning? METHODS: Thirty persons aged 60-85 years participated in the study, conducted in a laboratory environment. Data were collected by two synchronous video-cameras and a marker-based optoelectronic motion capture system as gold standard, to evaluate the gait parameters step length (SL), step width (SW), step duration (SD), single-stance duration (SSD) and double-stance duration (DSD). For reliability evaluations, data processing aided by a deep neural network model, involved three raters who conducted three repetitions of identifying anatomical keypoints in recordings of one randomly selected step from each of the participants. Validity was analysed using 95 % confidence intervals (CI) and p-values for method differences and Bland-Altman plots with limits of agreement. Inter- and intra-rater reliability were calculated as intraclass correlation coefficients (ICC) and standard errors of measurement. Smallest detectable change was calculated for inter-rater reliability. RESULTS: Mean ddifferences between video and the motion capture system data for SW, DSD, and SSD were significant (p < 0.001). However, mean differences for all parameters were small (-6.4%-13.0% of motion capture system) indicating good validity. Concerning reliability, almost all 95 % CI of the ICC estimates exceeded 0.90, indicating excellent reliability. Only inter-rater reliability for SW (95 % CI = 0.892;0.973) and one rater's intra-rater reliability for SSD (95 % CI = 0.793;0.951) were lower, but still showed good to excellent reliability. SIGNIFICANCE: The presented method for extraction of gait parameters from video appears suitable for valid and reliable quantification of gait. This opens up for analyses that may contribute to the knowledge of cognitive-motor interference in dual-task testing.


Assuntos
Marcha , Modalidades de Fisioterapia , Humanos , Reprodutibilidade dos Testes , Análise e Desempenho de Tarefas , Gravação em Vídeo
15.
Sci Transl Med ; 13(606)2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380771

RESUMO

Point mutations in the amyloid precursor protein gene (APP) cause familial Alzheimer's disease (AD) by increasing generation or altering conformation of amyloid ß (Aß). Here, we describe the Uppsala APP mutation (Δ690-695), the first reported deletion causing autosomal dominant AD. Affected individuals have an age at symptom onset in their early forties and suffer from a rapidly progressing disease course. Symptoms and biomarkers are typical of AD, with the exception of normal cerebrospinal fluid (CSF) Aß42 and only slightly pathological amyloid-positron emission tomography signals. Mass spectrometry and Western blot analyses of patient CSF and media from experimental cell cultures indicate that the Uppsala APP mutation alters APP processing by increasing ß-secretase cleavage and affecting α-secretase cleavage. Furthermore, in vitro aggregation studies and analyses of patient brain tissue samples indicate that the longer form of mutated Aß, AßUpp1-42Δ19-24, accelerates the formation of fibrils with unique polymorphs and their deposition into amyloid plaques in the affected brain.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Humanos
16.
Phys Ther ; 101(10)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34272869

RESUMO

OBJECTIVE: The purpose of the study was to establish reference values for the Uppsala-Dalarna Dementia and Gait (UDDGait) Timed "Up & Go" dual-task (TUGdt) test variables in cognitively healthy adults and to assess these variables' test-retest reliability. METHODS: For reference values, 166 participants were recruited with approximately equal numbers and proportions of women and men in the age groups 50 to 59, 60 to 69, 70 to 79, and 80+ years (mean age = 70 years, age range = 50-91 years, 51% women). For reliability testing, 43 individuals (mean age = 69 years, age range = 50-89 years, 51% women) were recruited. Two dt tests were carried out: TUGdt naming animals and TUGdt months backward, representing 8 test variables: time scores, costs (the relative difference between single-task and dt time scores), "number of animals," "number of months," "animals/10 seconds ," and "months/10 seconds ." Reference ranges for the variables were established by quantile regression in age- and sex-specific groups. For reliability, intraclass correlation coefficients (ICCs), standard error of measurement, minimal detectable change, and Bland-Altman plots were used. RESULTS: Reference values for the TUGdt test variables are presented for the 2.5th and 97.5th percentiles. The reliability of TUGdt time scores was excellent (ICCs between 0.85 and 0.86). "Number of animals" and "animals/10 seconds" as well as "months/10 seconds" showed fair to good levels of reliability (ICCs between 0.45 and 0.58), whereas the reliability for both cost measures and "number of months" was poor (ICCs between 0.34 and 0.39). CONCLUSION: Normative reference values, potentially useful for clinical and research purposes, were presented in 4 age- and sex-specific groups from 50 years and older. Reliability for the test variables varied between poor and excellent, the lower estimates partly explained by some variables being the ratio of 2 other variables. In UDDGait, TUGdt tests are intended for diagnostic and predictive purposes, for which these tests are promising and require further investigations. IMPACT: Normative reference values and test-retest reliability results for the UDDGait TUGdt test variables were presented. These results should be useful for both clinical and research purposes.


Assuntos
Cognição/fisiologia , Marcha , Voluntários Saudáveis , Psicometria/métodos , Valores de Referência , Caminhada/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Equilíbrio Postural/fisiologia , Reprodutibilidade dos Testes , Fatores Sexuais , Análise e Desempenho de Tarefas
17.
Cell Mol Life Sci ; 78(8): 4019-4033, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33837451

RESUMO

Epidemiological investigations show that mosaic loss of chromosome Y (LOY) in leukocytes is associated with earlier mortality and morbidity from many diseases in men. LOY is the most common acquired mutation and is associated with aberrant clonal expansion of cells, yet it remains unclear whether this mosaicism exerts a direct physiological effect. We studied DNA and RNA from leukocytes in sorted- and single-cells in vivo and in vitro. DNA analyses of sorted cells showed that men diagnosed with Alzheimer's disease was primarily affected with LOY in NK cells whereas prostate cancer patients more frequently displayed LOY in CD4 + T cells and granulocytes. Moreover, bulk and single-cell RNA sequencing in leukocytes allowed scoring of LOY from mRNA data and confirmed considerable variation in the rate of LOY across individuals and cell types. LOY-associated transcriptional effect (LATE) was observed in ~ 500 autosomal genes showing dysregulation in leukocytes with LOY. The fraction of LATE genes within specific cell types was substantially larger than the fraction of LATE genes shared between different subsets of leukocytes, suggesting that LOY might have pleiotropic effects. LATE genes are involved in immune functions but also encode proteins with roles in other diverse biological processes. Our findings highlight a surprisingly broad role for chromosome Y, challenging the view of it as a "genetic wasteland", and support the hypothesis that altered immune function in leukocytes could be a mechanism linking LOY to increased risk for disease.


Assuntos
Doença de Alzheimer/genética , Cromossomos Humanos Y , Mosaicismo , Neoplasias da Próstata/genética , Linfócitos T CD4-Positivos/metabolismo , Regulação da Expressão Gênica , Humanos , Células Matadoras Naturais/metabolismo , Leucócitos/metabolismo , Masculino
18.
J Alzheimers Dis ; 81(2): 629-640, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814444

RESUMO

BACKGROUND: Neuroinflammatory processes are common in neurodegenerative diseases such as Alzheimer's disease (AD) and frontotemporal dementia (FTD), but current knowledge is limited as to whether cerebrospinal fluid (CSF) levels of neuroinflammatory proteins are altered in these diseases. OBJECTIVE: To identify and characterize neuroinflammatory signatures in CSF from patients with AD, mild cognitive impairment (MCI), and FTD. METHODS: We used proximity extension assay and ANOVA to measure and compare levels of 92 inflammatory proteins in CSF from 42 patients with AD, 29 with MCI due to AD (MCI/AD), 22 with stable MCI, 42 with FTD, and 49 control subjects, correcting for age, gender, collection unit, and multiple testing. RESULTS: Levels of matrix metalloproteinase-10 (MMP-10) were increased in AD, MCI/AD, and FTD compared with controls (AD: fold change [FC] = 1.32, 95% confidence interval [CI] 1.14-1.53, q = 0.018; MCI/AD: FC = 1.53, 95% CI 1.20-1.94, q = 0.045; and FTD: FC = 1.42, 95% CI 1.10-1.83, q = 0.020). MMP-10 and eleven additional proteins were increased in MCI/AD, compared with MCI (q < 0.05). In FTD, 36 proteins were decreased, while none was decreased in AD or MCI/AD, compared with controls (q < 0.05). CONCLUSION: In this cross-sectional multi-center study, we found distinct patterns of CSF inflammatory marker levels in FTD and in both early and established AD, suggesting differing neuroinflammatory processes in the two disorders.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Demência Frontotemporal/líquido cefalorraquidiano , Inflamação/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico , Estudos Transversais , Feminino , Demência Frontotemporal/diagnóstico , Humanos , Inflamação/diagnóstico , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
19.
Artigo em Inglês | MEDLINE | ID: mdl-33153203

RESUMO

The aim of this study was to investigate whether Timed Up-and-Go (TUG) dual-task (TUGdt) tests predict dementia incidence among patients with subjective or mild cognitive impairment (SCI; MCI). Other study objectives were to determine whether TUGdt improves dementia prediction compared to a) demographic characteristics and standard cognitive tests alone; and b) TUG and Verbal Fluency performed separately. Patients (n = 172, age range 39-91 years, 78 women) with SCI or MCI performed TUGdt tests, including 1) naming animals and 2) reciting months backwards, and clinical cognitive tests at baseline. Diagnoses were identified at follow-up after 2.5 years. Logistic regression was used to predict dementia incidence, receiver operating characteristic (ROC) curves and c-statistics for predictive capacity. Analyses were stratified by age and gender. At follow-up, 51 patients had developed dementia. The TUGdt result "animals/10 s" was associated with dementia incidence (standardized odds ratio (OR) = 4.06, 95% confidence interval (CI) 2.28-7.23, p < 0.001), more so among patients under the median age of 72 years (standardized OR = 19.4, 95% CI 3.53-106.17, p < 0.001). TUGdt "animals/10 s" improved dementia prediction compared to demographic characteristics and standard tests alone (c-statistics 0.88 to 0.94) and single-task tests (c-statistics 0.86 to 0.89), but only in the younger patient group. TUGdt has the potential to become a useful tool for dementia prediction.


Assuntos
Disfunção Cognitiva , Demência , Memória Episódica , Adulto , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Estudos de Coortes , Demência/diagnóstico , Demência/epidemiologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
20.
Nat Metab ; 2(10): 1135-1148, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33067605

RESUMO

Circulating proteins are vital in human health and disease and are frequently used as biomarkers for clinical decision-making or as targets for pharmacological intervention. Here, we map and replicate protein quantitative trait loci (pQTL) for 90 cardiovascular proteins in over 30,000 individuals, resulting in 451 pQTLs for 85 proteins. For each protein, we further perform pathway mapping to obtain trans-pQTL gene and regulatory designations. We substantiate these regulatory findings with orthogonal evidence for trans-pQTLs using mouse knockdown experiments (ABCA1 and TRIB1) and clinical trial results (chemokine receptors CCR2 and CCR5), with consistent regulation. Finally, we evaluate known drug targets, and suggest new target candidates or repositioning opportunities using Mendelian randomization. This identifies 11 proteins with causal evidence of involvement in human disease that have not previously been targeted, including EGF, IL-16, PAPPA, SPON1, F3, ADM, CASP-8, CHI3L1, CXCL16, GDF15 and MMP-12. Taken together, these findings demonstrate the utility of large-scale mapping of the genetics of the proteome and provide a resource for future precision studies of circulating proteins in human health.


Assuntos
Sistema Cardiovascular/metabolismo , Mapeamento Cromossômico , Sistemas de Liberação de Medicamentos , Genômica , Transportador 1 de Cassete de Ligação de ATP/genética , Asma/genética , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla , Humanos , Doenças Inflamatórias Intestinais/genética , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Desequilíbrio de Ligação , Análise da Randomização Mendeliana , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteoma , Locos de Características Quantitativas , Receptores CCR2/genética , Receptores CCR5/genética
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