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1.
Biomed Environ Sci ; 34(1): 19-28, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33531104

RESUMO

Objective: In the present study, the ABCA1 was used as a label to capture specific exosomes, the level of ABCA1-labeled exosomal microRNA-135a (miR-135a) was evaluated for the diagnosis of Alzheimer's disease (AD), especially in patients with early stages of AD. Methods: This is a preliminary research focused on the levels of ABCA1 in WBCs, RBCs, HT-22 cells, and neuron cells. The diagnostic value of ABCA1-labeled exosomal miR-135a was examined using the CSF and serum of APP/PS1 double transgenic mice, and 152 patients with SCD, 131 patients with MCI, 198 patients with DAT, and 30 control subjects. Results: The level of ABCA1 exosomes harvested from HT-22 cells and neuron culture medium was significantly higher compared to that of RBCs and WBCs ( P < 0.05). The levels of ABCA1-labeled exosomal miR-135a increased in the CSF of MCI and DAT group compared to those of control group ( P < 0.05), slightly increased ( P > 0.05) in the serum of SCD patient group, and significantly increased in MCI and DAT patient groups compared to those of the control group ( P < 0.05). Conclusion: This study outlines a method to capture specific exosomes and detect them using immunological methods, which is more efficient for early diagnosis of AD.


Assuntos
Transportador 1 de Cassete de Ligação de ATP , Disfunção Cognitiva/sangue , Exossomos , MicroRNAs/sangue , Transportador 1 de Cassete de Ligação de ATP/sangue , Transportador 1 de Cassete de Ligação de ATP/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Animais , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Linhagem Celular , Disfunção Cognitiva/líquido cefalorraquidiano , Eritrócitos/metabolismo , Feminino , Humanos , Leucócitos/metabolismo , Masculino , Camundongos Transgênicos , Neurônios/metabolismo
2.
Neurology ; 95(16): e2295-e2304, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32878992

RESUMO

OBJECTIVE: To determine the cognitive consequences of anticholinergic medications (aCH) in cognitively normal older adults as well as interactive effects of genetic and CSF Alzheimer disease (AD) risk factors. METHODS: A total of 688 cognitively normal participants from the Alzheimer's Disease Neuroimaging Initiative were evaluated (mean age 73.5 years, 49.6% female). Cox regression examined risk of progression to mild cognitive impairment (MCI) over a 10-year period and linear mixed effects models examined 3-year rates of decline in memory, executive function, and language as a function of aCH. Interactions with APOE ε4 genotype and CSF biomarker evidence of AD pathology were also assessed. RESULTS: aCH+ participants had increased risk of progression to MCI (hazard ratio [HR] 1.47, p = 0.02), and there was a significant aCH × AD risk interaction such that aCH+/ε4+ individuals showed greater than 2-fold increased risk (HR 2.69, p < 0.001) for incident MCI relative to aCH-/ε4-), while aCH+/CSF+) individuals demonstrated greater than 4-fold (HR 4.89, p < 0.001) increased risk relative to aCH-/CSF-. Linear mixed effects models revealed that aCH predicted a steeper slope of decline in memory (t = -2.35, p = 0.02) and language (t = -2.35, p = 0.02), with effects exacerbated in individuals with AD risk factors. CONCLUSIONS: aCH increased risk of incident MCI and cognitive decline, and effects were significantly enhanced among individuals with genetic risk factors and CSF-based AD pathophysiologic markers. Findings underscore the adverse impact of aCH medications on cognition and the need for deprescribing trials, particularly among individuals with elevated risk for AD.


Assuntos
Doença de Alzheimer/epidemiologia , Antagonistas Colinérgicos/efeitos adversos , Disfunção Cognitiva/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/genética , Apolipoproteínas E/genética , Biomarcadores/líquido cefalorraquidiano , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/genética , Progressão da Doença , Feminino , Predisposição Genética para Doença , Humanos , Incidência , Masculino
3.
Neurology ; 95(17): e2378-e2388, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32788242

RESUMO

OBJECTIVE: To evaluate sex differences in CSF biomarkers, taking the potential modifying role of clinical disease stage and APOE ε4 genotype into account. METHOD: We included participants (n = 1,801) with probable Alzheimer disease (AD) dementia (n = 937), mild cognitive impairment (MCI; n = 437), and subjective cognitive decline (SCD; n = 427). Main outcomes were CSF ß-amyloid1-42 (Aß42), total tau (t-Tau), and tau phosphorylated at threonine 181 (p-Tau) levels. Age-corrected 3-way interactions between sex, disease stage (i.e., syndrome diagnosis at baseline), and APOE ε4 were tested with linear regression analyses for each outcome measure. In case of significant interactions (p < 0.05), sex differences were further evaluated by stratifying analyses for clinical disease stage and APOE ε4 genotype, including age as a covariate. RESULTS: Three-way interactions were significant for t-Tau (p < 0.001) and p-Tau (p < 0.01) but not Aß42. In APOE ε4 carriers, women showed higher p-Tau concentrations than men in SCD (Cohen d [95% confidence interval]: t-Tau = 0.52 [0.19-0.84], p < 0.001; p-Tau = 0.44 [0.11-0.77] p = 0.004) and MCI (Cohen d [95% CI]: t-Tau = 0.54 [0.28-0.80], p < 0.001; p-Tau = 0.52 [0.26-0.77], p < 0.001) but not in AD dementia. In APOE ε4 noncarriers, women showed higher p-Tau concentrations in MCI (Cohen d [95% CI]: t-Tau = 0.49 [0.17-0.80], p = 0.002; p-Tau = 0.47 [0.16-0.78], p = 0.003) and AD dementia (Cohen d [95% CI]: t-Tau = 0.42 [0.19-0.65], p < 0.001; p-Tau = 0.38 [0.15-0.61] p = 0.002) but not in SCD. CONCLUSIONS: Within APOE ε4 carriers, sex differences in CSF p-Tau are more evident in early disease stages, whereas for APOE ε4 noncarriers, sex differences are more evident in advanced disease stages. These findings suggest that the effect of APOE ε4 on sex differences in CSF biomarkers depends on disease stage in AD.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Biomarcadores/líquido cefalorraquidiano , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/genética , Progressão da Doença , Feminino , Genótipo , Heterozigoto , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fosforilação , Caracteres Sexuais , Proteínas tau/líquido cefalorraquidiano
4.
PLoS Med ; 17(8): e1003289, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817639

RESUMO

BACKGROUND: The ε4 allele of apolipoprotein E (APOE) gene and increasing age are two of the most important known risk factors for developing Alzheimer disease (AD). The diagnosis of AD based on clinical symptoms alone is known to have poor specificity; recently developed diagnostic criteria based on biomarkers that reflect underlying AD neuropathology allow better assessment of the strength of the associations of risk factors with AD. Accordingly, we examined the global and age-specific association between APOE genotype and AD by using the A/T/N classification, relying on the cerebrospinal fluid (CSF) levels of ß-amyloid peptide (A, ß-amyloid deposition), phosphorylated tau (T, pathologic tau), and total tau (N, neurodegeneration) to identify patients with AD. METHODS AND FINDINGS: This case-control study included 1,593 white AD cases (55.4% women; mean age 72.8 [range = 44-96] years) with abnormal values of CSF biomarkers from nine European memory clinics and the American Alzheimer's Disease Neuroimaging Initiative (ADNI) study. A total of 11,723 dementia-free controls (47.1% women; mean age 65.6 [range = 44-94] years) were drawn from two longitudinal cohort studies (Whitehall II and Three-City), in which incident cases of dementia over the follow-up were excluded from the control population. Odds ratio (OR) and population attributable fraction (PAF) for AD associated with APOE genotypes were determined, overall and by 5-year age categories. In total, 63.4% of patients with AD and 22.6% of population controls carried at least one APOE ε4 allele. Compared with non-ε4 carriers, heterozygous ε4 carriers had a 4.6 (95% confidence interval 4.1-5.2; p < 0.001) and ε4/ε4 homozygotes a 25.4 (20.4-31.2; p < 0.001) higher OR of AD in unadjusted analysis. This association was modified by age (p for interaction < 0.001). The PAF associated with carrying at least one ε4 allele was greatest in the 65-70 age group (69.7%) and weaker before 55 years (14.2%) and after 85 years (22.6%). The protective effect of APOE ε2 allele for AD was unaffected by age. Main study limitations are that analyses were based on white individuals and AD cases were drawn from memory centers, which may not be representative of the general population of patients with AD. CONCLUSIONS: In this study, we found that AD diagnosis based on biomarkers was associated with APOE ε4 carrier status, with a higher OR than previously reported from studies based on only clinical AD criteria. This association differs according to age, with the strongest effect at 65-70 years. These findings highlight the need for early interventions for dementia prevention to mitigate the effect of APOE ε4 at the population level.


Assuntos
Envelhecimento/líquido cefalorraquidiano , Envelhecimento/genética , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/genética , Apolipoproteína E4/líquido cefalorraquidiano , Apolipoproteína E4/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
5.
BMC Neurol ; 20(1): 317, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854643

RESUMO

BACKGROUND: The ventricular system plays a vital role in blood-cerebrospinal fluid (CSF) exchange and interstitial fluid-CSF drainage pathways. CSF is formed in the specialized secretory tissue called the choroid plexus, which consists of epithelial cells, fenestrated capillaries and the highly vascularized stroma. Very little is currently known about the role played by the ventricles and the choroid plexus tissue in aging and Alzheimer's disease (AD). METHODS: In this study, we used our state-of-the-art proteomic platform, a liquid chromatography/mass spectrometry (LC-MS/MS) approach coupled with Tandem Mass Tag isobaric labeling to conduct a detailed unbiased proteomic analyses of autopsied tissue isolated from the walls of the inferior horn of the lateral ventricles in AD (77.2 ± 0.6 yrs), age-matched controls (77.0 ± 0.5 yrs), and nonagenarian cases (93.2 ± 1.1 yrs). RESULTS: Ingenuity pathway analyses identified phagosome maturation, impaired tight-junction signaling, and glucose/mannose metabolism as top significantly regulated pathways in controls vs nonagenarians. In matched-control vs AD cases we identified alterations in mitochondrial bioenergetics, oxidative stress, remodeling of epithelia adherens junction, macrophage recruitment and phagocytosis, and cytoskeletal dynamics. Nonagenarian vs AD cases demonstrated augmentation of oxidative stress, changes in gluconeogenesis-glycolysis pathways, and cellular effects of choroidal smooth muscle cell vasodilation. Amyloid plaque score uniquely correlated with remodeling of epithelial adherens junctions, Fc γ-receptor mediated phagocytosis, and alterations in RhoA signaling. Braak staging was uniquely correlated with altered iron homeostasis, superoxide radical degradation and phagosome maturation. CONCLUSIONS: These changes provide novel insights to explain the compromise to the physiological properties and function of the ventricles/choroid plexus system in nonagenarian aging and AD pathogenesis. The pathways identified could provide new targets for therapeutic strategies to mitigate the divergent path towards AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Encéfalo/patologia , Ventrículos Laterais/patologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Doença de Alzheimer/líquido cefalorraquidiano , Ventrículos Cerebrais/patologia , Plexo Corióideo/patologia , Cromatografia Líquida , Feminino , Humanos , Masculino , Placa Amiloide/patologia , Proteômica , Espectrometria de Massas em Tandem
6.
Neuron ; 106(6): 881-883, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32553204
7.
Lancet ; 395(10242): 1988-1997, 2020 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-32593336

RESUMO

BACKGROUND: Alzheimer's disease and its complications are the leading cause of death in adults with Down syndrome. Studies have assessed Alzheimer's disease in individuals with Down syndrome, but the natural history of biomarker changes in Down syndrome has not been established. We characterised the order and timing of changes in biomarkers of Alzheimer's disease in a population of adults with Down syndrome. METHODS: We did a dual-centre cross-sectional study of adults with Down syndrome recruited through a population-based health plan in Barcelona (Spain) and through services for people with intellectual disabilities in Cambridge (UK). Cognitive impairment in participants with Down syndrome was classified with the Cambridge Cognitive Examination for Older Adults with Down Syndrome (CAMCOG-DS). Only participants with mild or moderate disability were included who had at least one of the following Alzheimer's disease measures: apolipoprotein E allele carrier status; plasma concentrations of amyloid ß peptides 1-42 and 1-40 and their ratio (Aß1-42/1-40), total tau protein, and neurofilament light chain (NFL); tau phosphorylated at threonine 181 (p-tau), and NFL in cerebrospinal fluid (CSF); and one or more of PET with 18F-fluorodeoxyglucose, PET with amyloid tracers, and MRI. Cognitively healthy euploid controls aged up to 75 years who had no biomarker abnormalities were recruited from the Sant Pau Initiative on Neurodegeneration. We used a first-order locally estimated scatterplot smoothing curve to determine the order and age at onset of the biomarker changes, and the lowest ages at the divergence with 95% CIs are also reported where appropriate. FINDINGS: Between Feb 1, 2013, and June 28, 2019 (Barcelona), and between June 1, 2009, and Dec 31, 2014 (Cambridge), we included 388 participants with Down syndrome (257 [66%] asymptomatic, 48 [12%] with prodromal Alzheimer's disease, and 83 [21%] with Alzheimer's disease dementia) and 242 euploid controls. CSF Aß1-42/1-40 and plasma NFL values changed in individuals with Down syndrome as early as the third decade of life, and amyloid PET uptake changed in the fourth decade. 18F-fluorodeoxyglucose PET and CSF p-tau changes occurred later in the fourth decade of life, followed by hippocampal atrophy and changes in cognition in the fifth decade of life. Prodromal Alzheimer's disease was diagnosed at a median age of 50·2 years (IQR 47·5-54·1), and Alzheimer's disease dementia at 53·7 years (49·5-57·2). Symptomatic Alzheimer's disease prevalence increased with age in individuals with Down syndrome, reaching 90-100% in the seventh decade of life. INTERPRETATION: Alzheimer's disease in individuals with Down syndrome has a long preclinical phase in which biomarkers follow a predictable order of changes over more than two decades. The similarities with sporadic and autosomal dominant Alzheimer's disease and the prevalence of Down syndrome make this population a suitable target for Alzheimer's disease preventive treatments. FUNDING: Instituto de Salud Carlos III, Fundació Bancaria La Caixa, Fundació La Marató de TV3, Medical Research Council, and National Institutes of Health.


Assuntos
Doença de Alzheimer/metabolismo , Biomarcadores/sangue , Síndrome de Down/complicações , Adulto , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/epidemiologia , Peptídeos beta-Amiloides/metabolismo , Amiloidose/diagnóstico por imagem , Amiloidose/patologia , Apolipoproteínas E/metabolismo , Estudos de Casos e Controles , Disfunção Cognitiva/psicologia , Estudos Transversais , Síndrome de Down/epidemiologia , Síndrome de Down/mortalidade , Síndrome de Down/psicologia , Fluordesoxiglucose F18/administração & dosagem , Humanos , Imagem por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons/métodos , Prevalência , Espanha/epidemiologia , Reino Unido/epidemiologia , Proteínas tau/metabolismo
8.
Neurology ; 95(8): e953-e961, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32586895

RESUMO

OBJECTIVE: To assess the ability of a combination of synaptic CSF biomarkers to separate Alzheimer disease (AD) and non-AD disorders and to help in the differential diagnosis between neurocognitive diseases. METHODS: This was a retrospective cross-sectional monocentric study. All participants explored with CSF assessments for neurocognitive decline were invited to participate. After complete clinical and imaging evaluations, 243 patients were included. CSF synaptic (GAP-43, neurogranin, SNAP-25 total, SNAP-25aa40, synaptotagmin-1) and AD biomarkers were blindly quantified with ELISA or mass spectrometry. Statistical analysis compared CSF levels between the various groups of AD dementias (n = 81), mild cognitive impairment (MCI)-AD (n = 30), other MCI (n = 49), other dementias (OD) (n = 49), and neurologic controls (n = 35) and their discriminatory powers. RESULTS: All synaptic biomarkers were significantly increased in patients with MCI-AD and AD-dementia compared to the other groups. All synaptic biomarkers could efficiently discriminate AD dementias from OD (AUC ≥0.80). All but synaptotagmin were also able to discriminate patients with MCI-AD from controls (area under the curve [AUC] ≥0.85) and those with AD dementias from controls (AUC ≥0.80). Overall, CSF SNAP-25aa40 had the highest discriminative power (AUC 0.93 between patients with AD dementias and controls or OD, AUC 0.90 between those with MCI-AD and controls). Higher levels were associated with 2 alleles of APOE ε4. CONCLUSION: All synaptic biomarkers tested had a good discriminatory power to distinguish patients with AD abnormal CSF from those with non-AD disorders. SNAP25aa40 demonstrated the highest power to discriminate AD CSF-positive patients from patients without AD and neurologic controls in this cohort. CLASSIFICATION OF EVIDENCE: This retrospective study provides Class II evidence that CSF synaptic biomarkers discriminate patients with AD from those without AD.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Idoso , Estudos Transversais , Diagnóstico Diferencial , Feminino , Proteína GAP-43/líquido cefalorraquidiano , Humanos , Masculino , Pessoa de Meia-Idade , Neurogranina/líquido cefalorraquidiano , Estudos Retrospectivos , Sensibilidade e Especificidade , Sinapses/metabolismo , Sinapses/patologia , Proteína 25 Associada a Sinaptossoma/líquido cefalorraquidiano , Sinaptotagmina I/líquido cefalorraquidiano
9.
PLoS One ; 15(5): e0232785, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469871

RESUMO

BACKGROUND: Alzheimer's disease (AD) pathology precedes symptoms and its detection can identify at-risk individuals who may benefit from early treatment. Since the retinal nerve fiber layer (RNFL) is depleted in established AD, we tested whether its thickness can predict whether cognitively healthy (CH) individuals have a normal or pathological cerebrospinal fluid (CSF) Aß42 (A) and tau (T) ratio. METHODS: As part of an ongoing longitudinal study, we enrolled CH individuals, excluding those with cognitive impairment and significant ocular pathology. We classified the CH group into two sub-groups, normal (CH-NAT, n = 16) or pathological (CH-PAT, n = 27), using a logistic regression model from the CSF AT ratio that identified >85% of patients with a clinically probable AD diagnosis. Spectral-domain optical coherence tomography (OCT) was acquired for RNFL, ganglion cell-inner plexiform layer (GC-IPL), and macular thickness. Group differences were tested using mixed model repeated measures and a classification model derived using multiple logistic regression. RESULTS: Mean age (± standard deviation) in the CH-PAT group (n = 27; 75.2 ± 8.4 years) was similar (p = 0.50) to the CH-NAT group (n = 16; 74.1 ± 7.9 years). Mean RNFL (standard error) was thinner in the CH-PAT group by 9.8 (2.7) µm; p < 0.001. RNFL thickness classified CH-NAT vs. CH-PAT with 87% sensitivity and 56.3% specificity. CONCLUSIONS: Our retinal data predict which individuals have CSF biomarkers of AD pathology before cognitive deficits are detectable with 87% sensitivity. Such results from easy-to-acquire, objective and non-invasive measurements of the RNFL merit further study of OCT technology to monitor or screen for early AD pathology.


Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Disfunção Cognitiva/genética , Proteínas tau/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Amiloidose/líquido cefalorraquidiano , Amiloidose/diagnóstico por imagem , Amiloidose/genética , Amiloidose/patologia , Biomarcadores/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/metabolismo , Fibras Nervosas/patologia , Disco Óptico/diagnóstico por imagem , Disco Óptico/metabolismo , Disco Óptico/patologia , Retina/diagnóstico por imagem , Retina/metabolismo , Retina/patologia , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica , Proteínas tau/líquido cefalorraquidiano
10.
Ann Neurol ; 88(1): 183-194, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32468646

RESUMO

OBJECTIVE: Preclinical evidence with nilotinib, a US Food and Drug Administration (FDA)-approved drug for leukemia, indicates improvement in Alzheimer's disease phenotypes. We investigated whether nilotinib is safe, and detectable in cerebrospinal fluid, and alters biomarkers and clinical decline in Alzheimer's disease. METHODS: This single-center, phase 2, randomized, double-blind, placebo-controlled study investigated the safety, tolerability, and pharmacokinetics of nilotinib, and measured biomarkers in participants with mild to moderate dementia due to Alzheimer's disease. The diagnosis was supported by cerebrospinal fluid or amyloid positron emission tomography biomarkers. Nilotinib 150 mg versus matching placebo was taken orally once daily for 26 weeks followed by nilotinib 300 mg versus placebo for another 26 weeks. RESULTS: Of the 37 individuals enrolled, 27 were women and the mean (SD) age was 70.7 (6.48) years. Nilotinib was well-tolerated, although more adverse events, particularly mood swings, were noted with the 300 mg dose. In the nilotinib group, central nervous system (CNS) amyloid burden was significantly reduced in the frontal lobe compared to the placebo group. Cerebrospinal fluid Aß40 was reduced at 6 months and Aß42 was reduced at 12 months in the nilotinib group compared to the placebo. Hippocampal volume loss was attenuated (-27%) at 12 months and phospho-tau-181 was reduced at 6 months and 12 months in the nilotinib group. INTERPRETATION: Nilotinib is safe and achieves pharmacologically relevant cerebrospinal fluid concentrations. Biomarkers of disease were altered in response to nilotinib treatment. These data support a larger, longer, multicenter study to determine the safety and efficacy of nilotinib in Alzheimer's disease. ANN NEUROL 2020 ANN NEUROL 2020;88:183-194.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Encéfalo/diagnóstico por imagem , Proteínas Tirosina Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons , Resultado do Tratamento , Proteínas tau/líquido cefalorraquidiano
11.
Neurobiol Aging ; 91: 66-75, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32224066

RESUMO

Cognitive impairments and circadian rhythm disorders are the main clinical manifestations of Alzheimer's disease (AD). Orexin has been reported as abnormally elevated in the cerebrospinal fluid of AD patients, accompanied with cognitive impairments. Our recent research revealed that suvorexant, a dual orexin receptor antagonist, could improve behavioral circadian rhythm disorders in 9-month-old APP/PS1 mice. Here we further observed whether suvorexant could ameliorate the cognitive decline in APP/PS1 mice by using behavioral tests, and investigated the possible mechanisms by in vivo electrophysiological recording, western blot, and immunochemistry. The results showed that suvorexant treatment effectively ameliorated the cognitive impairments, alleviated in vivo hippocampal long-term potentiation suppression, restored the circadian phosphorylated CREB expression in the hippocampus, and reduced amyloid-ß protein deposition in the hippocampus and cortex in APP/PS1 mice. These results indicate that the neuroprotective effects of suvorexant against AD are involved in the reduction of amyloid-ß plaques, improvement of synaptic plasticity, and circadian expression of phosphorylated CREB, suggesting that suvorexant could be beneficial to the prevention and treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Azepinas/farmacologia , Azepinas/uso terapêutico , Transtornos Cronobiológicos/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Neuroprostanos , Antagonistas dos Receptores de Orexina , Triazóis/farmacologia , Triazóis/uso terapêutico , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Transtornos Cronobiológicos/etiologia , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/etiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Potenciação de Longa Duração/efeitos dos fármacos , Camundongos Transgênicos , Plasticidade Neuronal/efeitos dos fármacos , Orexinas/líquido cefalorraquidiano
12.
Nat Commun ; 11(1): 1683, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32246036

RESUMO

Cerebrospinal fluid (CSF) p-tau181 (tau phosphorylated at threonine 181) is an established biomarker of Alzheimer's disease (AD), reflecting abnormal tau metabolism in the brain. Here we investigate the performance of CSF p-tau217 as a biomarker of AD in comparison to p-tau181. In the Swedish BioFINDER cohort (n = 194), p-tau217 shows stronger correlations with the tau positron emission tomography (PET) tracer [18F]flortaucipir, and more accurately identifies individuals with abnormally increased [18F]flortaucipir retention. Furthermore, longitudinal increases in p-tau217 are higher compared to p-tau181 and better correlate with [18F]flortaucipir uptake. P-tau217 correlates better than p-tau181 with CSF and PET measures of neocortical amyloid-ß burden and more accurately distinguishes AD dementia from non-AD neurodegenerative disorders. Higher correlations between p-tau217 and [18F]flortaucipir are corroborated in an independent EXPEDITION3 trial cohort (n = 32). The main results are validated using a different p-tau217 immunoassay. These findings suggest that p-tau217 might be more useful than p-tau181 in the diagnostic work up of AD.


Assuntos
Doença de Alzheimer/diagnóstico , Proteínas tau/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Carbolinas/administração & dosagem , Meios de Contraste/administração & dosagem , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação , Tomografia por Emissão de Pósitrons , Suécia , Proteínas tau/metabolismo
13.
Nat Med ; 26(5): 769-780, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32284590

RESUMO

Our understanding of Alzheimer's disease (AD) pathophysiology remains incomplete. Here we used quantitative mass spectrometry and coexpression network analysis to conduct the largest proteomic study thus far on AD. A protein network module linked to sugar metabolism emerged as one of the modules most significantly associated with AD pathology and cognitive impairment. This module was enriched in AD genetic risk factors and in microglia and astrocyte protein markers associated with an anti-inflammatory state, suggesting that the biological functions it represents serve a protective role in AD. Proteins from this module were elevated in cerebrospinal fluid in early stages of the disease. In this study of >2,000 brains and nearly 400 cerebrospinal fluid samples by quantitative proteomics, we identify proteins and biological processes in AD brains that may serve as therapeutic targets and fluid biomarkers for the disease.


Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Encéfalo/metabolismo , Líquido Cefalorraquidiano/metabolismo , Metabolismo Energético , Microglia/metabolismo , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/patologia , Animais , Astrócitos/patologia , Astrócitos/fisiologia , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Líquido Cefalorraquidiano/química , Estudos de Coortes , Progressão da Doença , Feminino , Redes Reguladoras de Genes/fisiologia , Humanos , Masculino , Espectrometria de Massas , Redes e Vias Metabólicas , Camundongos , Microglia/patologia , Microglia/fisiologia , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/líquido cefalorraquidiano , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/fisiologia , Proteômica/métodos , Tamanho da Amostra , Fatores de Tempo
14.
Brain ; 143(3): 993-1009, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32203580

RESUMO

Alzheimer's disease neurodegeneration is thought to spread across anatomically and functionally connected brain regions. However, the precise sequence of spread remains ambiguous. The prevailing model used to guide in vivo human neuroimaging and non-human animal research assumes that Alzheimer's degeneration starts in the entorhinal cortices, before spreading to the temporoparietal cortex. Challenging this model, we previously provided evidence that in vivo markers of neurodegeneration within the nucleus basalis of Meynert (NbM), a subregion of the basal forebrain heavily populated by cortically projecting cholinergic neurons, precedes and predicts entorhinal degeneration. There have been few systematic attempts at directly comparing staging models using in vivo longitudinal biomarker data, and none to our knowledge testing if comparative evidence generalizes across independent samples. Here we addressed the sequence of pathological staging in Alzheimer's disease using two independent samples of the Alzheimer's Disease Neuroimaging Initiative (n1 = 284; n2 = 553) with harmonized CSF assays of amyloid-ß and hyperphosphorylated tau (pTau), and longitudinal structural MRI data over 2 years. We derived measures of grey matter degeneration in a priori NbM and the entorhinal cortical regions of interest. To examine the spreading of degeneration, we used a predictive modelling strategy that tests whether baseline grey matter volume in a seed region accounts for longitudinal change in a target region. We demonstrated that predictive spread favoured the NbM→entorhinal over the entorhinal→NbM model. This evidence generalized across the independent samples. We also showed that CSF concentrations of pTau/amyloid-ß moderated the observed predictive relationship, consistent with evidence in rodent models of an underlying trans-synaptic mechanism of pathophysiological spread. The moderating effect of CSF was robust to additional factors, including clinical diagnosis. We then applied our predictive modelling strategy to an exploratory whole-brain voxel-wise analysis to examine the spatial specificity of the NbM→entorhinal model. We found that smaller baseline NbM volumes predicted greater degeneration in localized regions of the entorhinal and perirhinal cortices. By contrast, smaller baseline entorhinal volumes predicted degeneration in the medial temporal cortex, recapitulating a prior influential staging model. Our findings suggest that degeneration of the basal forebrain cholinergic projection system is a robust and reliable upstream event of entorhinal and neocortical degeneration, calling into question a prevailing view of Alzheimer's disease pathogenesis.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Prosencéfalo Basal/patologia , Progressão da Doença , Degeneração Neural/patologia , Proteínas tau/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Núcleo Basal de Meynert/patologia , Biomarcadores , Bases de Dados Factuais , Córtex Entorrinal/patologia , Feminino , Substância Cinzenta/patologia , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética , Masculino , Neuroimagem , Fosforilação
15.
Nat Med ; 26(3): 398-407, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32161412

RESUMO

Development of tau-based therapies for Alzheimer's disease requires an understanding of the timing of disease-related changes in tau. We quantified the phosphorylation state at multiple sites of the tau protein in cerebrospinal fluid markers across four decades of disease progression in dominantly inherited Alzheimer's disease. We identified a pattern of tau staging where site-specific phosphorylation changes occur at different periods of disease progression and follow distinct trajectories over time. These tau phosphorylation state changes are uniquely associated with structural, metabolic, neurodegenerative and clinical markers of disease, and some (p-tau217 and p-tau181) begin with the initial increases in aggregate amyloid-ß as early as two decades before the development of aggregated tau pathology. Others (p-tau205 and t-tau) increase with atrophy and hypometabolism closer to symptom onset. These findings provide insights into the pathways linking tau, amyloid-ß and neurodegeneration, and may facilitate clinical trials of tau-based treatments.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Padrões de Herança/genética , Proteínas tau/metabolismo , Adulto , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Atrofia , Encéfalo/patologia , Cognição , Progressão da Doença , Feminino , Fluordesoxiglucose F18/química , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Fosforilação , Placa Amiloide/patologia , Solubilidade , Proteínas tau/líquido cefalorraquidiano
16.
Nat Med ; 26(3): 387-397, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32123386

RESUMO

With the potential development of new disease-modifying Alzheimer's disease (AD) therapies, simple, widely available screening tests are needed to identify which individuals, who are experiencing symptoms of cognitive or behavioral decline, should be further evaluated for initiation of treatment. A blood-based test for AD would be a less invasive and less expensive screening tool than the currently approved cerebrospinal fluid or amyloid ß positron emission tomography (PET) diagnostic tests. We examined whether plasma tau phosphorylated at residue 181 (pTau181) could differentiate between clinically diagnosed or autopsy-confirmed AD and frontotemporal lobar degeneration. Plasma pTau181 concentrations were increased by 3.5-fold in AD compared to controls and differentiated AD from both clinically diagnosed (receiver operating characteristic area under the curve of 0.894) and autopsy-confirmed frontotemporal lobar degeneration (area under the curve of 0.878). Plasma pTau181 identified individuals who were amyloid ß-PET-positive regardless of clinical diagnosis and correlated with cortical tau protein deposition measured by 18F-flortaucipir PET. Plasma pTau181 may be useful to screen for tau pathology associated with AD.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Degeneração Lobar Frontotemporal/sangue , Degeneração Lobar Frontotemporal/diagnóstico , Proteínas tau/sangue , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Amiloide/metabolismo , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Cognição , Feminino , Degeneração Lobar Frontotemporal/genética , Degeneração Lobar Frontotemporal/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Proteínas de Neurofilamentos/sangue , Fosforilação , Tomografia por Emissão de Pósitrons , Índice de Gravidade de Doença , Proteínas tau/líquido cefalorraquidiano , Proteínas tau/genética
17.
Int J Geriatr Psychiatry ; 35(5): 581-588, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32011757

RESUMO

OBJECTIVES: The aim of this study was to examine whether the discrepancy between participant and informant estimation of memory decline can predict MCI prognosis. METHODS: Analyses involved data from individuals with MCI enrolled in the Alzheimer's Disease Neuroimaging Initiative (ADNI) who filled the Everyday Cognition questionnaire. Participants who underestimated (N = 112) and overestimated (N = 157) their memory decline were compared on memory tasks, brain volume, and cerebrospinal markers, at study entry and after 24 months. RESULTS: Individuals who underestimated their memory decline performed more poorly on memory tests, had smaller hippocampus volume, and greater Alzheimer's disease pathology than did individuals who overestimated their cognitive decline. Longitudinal comparisons demonstrated that individuals who underestimated their decline deteriorated more significantly in memory and in brain measures. CONCLUSIONS: Underestimation of memory decline should raise clinicians' suspicion of the existence of AD pathology in individuals with MCI.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/anatomia & histologia , Disfunção Cognitiva/diagnóstico , Transtornos da Memória/fisiopatologia , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/psicologia , Biomarcadores/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Memória , Transtornos da Memória/etiologia , Neuroimagem , Testes Neuropsicológicos , Prognóstico
19.
Int J Mol Sci ; 21(3)2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32050587

RESUMO

In recent years, the idea that sleep is critical for cognitive processing has gained strength. Alzheimer's disease (AD) is the most common form of dementia worldwide and presents a high prevalence of sleep disturbances. However, it is difficult to establish causal relations, since a vicious circle emerges between different aspects of the disease. Nowadays, we know that sleep is crucial to consolidate memory and to remove the excess of beta-amyloid and hyperphosphorilated tau accumulated in AD patients' brains. In this review, we discuss how sleep disturbances often precede in years some pathological traits, as well as cognitive decline, in AD. We describe the relevance of sleep to memory consolidation, focusing on changes in sleep patterns in AD in contrast to normal aging. We also analyze whether sleep alterations could be useful biomarkers to predict the risk of developing AD and we compile some sleep-related proposed biomarkers. The relevance of the analysis of the sleep microstructure is highlighted to detect specific oscillatory patterns that could be useful as AD biomarkers.


Assuntos
Doença de Alzheimer/etiologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Transtornos do Sono-Vigília/etiologia , Proteínas tau/líquido cefalorraquidiano , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/fisiopatologia , Biomarcadores/líquido cefalorraquidiano , Cognição , Humanos , Memória , Transtornos do Sono-Vigília/líquido cefalorraquidiano , Transtornos do Sono-Vigília/fisiopatologia
20.
Neurology ; 94(11): e1190-e1200, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32015176

RESUMO

OBJECTIVE: To investigate relationships between flortaucipir (FTP) uptake, age, and established Alzheimer disease (AD) markers in asymptomatic adults at increased risk of AD. METHODS: One-hundred nineteen individuals with a family history of AD (Presymptomatic Evaluation of Experimental or Novel Treatments of Alzheimer's Disease [PREVENT-AD] cohort, mean age 67 ± 5 years) underwent tau-PET ([18F]FTP), ß-amyloid (Aß)-PET ([18F]NAV4694 [NAV]), and cognitive assessment. Seventy-four participants also had CSF phosphorylated tau and total tau data available. We investigated the association between age and FTP in this relatively young cohort of older adults. We also investigated regional FTP standardized uptake value ratio (SUVR) differences between Aß-positive and Aß-negative individuals and regional correlations between FTP and NAV retention. In cortical regions showing consistent associations across analyses, we assessed whether FTP was in addition related to CSF tau and cognitive performance. Lastly, we identified the lowest FTP value at which associations with Aß-PET, CSF, and cognition were detectable. RESULTS: Increased age was associated only with amygdala and transverse temporal lobe FTP retention. Aß-positive individuals had higher FTP SUVR values in several brain regions, further showing correlation with NAV load through the cortex. Increased FTP SUVRs in medial temporal regions were associated with increased CSF tau values and worse cognition. The SUVRs at which associations between entorhinal FTP SUVR and other AD markers were first detected differed by modality, with a detection point of 1.12 for CSF values, 1.2 for Aß-PET, and 1.4 for cognition. CONCLUSIONS: Relatively low FTP-PET SUVRs are associated with pathologic markers of AD in the preclinical phase of the disease. Adjustment in the tau threshold should be considered, depending on the purpose of the tau classification.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Proteínas tau/análise , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Encéfalo/metabolismo , Encéfalo/patologia , Carbolinas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Proteínas tau/metabolismo
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