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1.
JAMA Neurol ; 79(11): 1113-1121, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36121669

RESUMO

Importance: Alzheimer disease (AD), a neurodegenerative disease characterized by ß-amyloid plaques and τ tangles in the brain, represents an unmet medical need with no fully approved therapeutics to modify disease progression. Objective: To investigate the safety and efficacy of crenezumab, a humanized monoclonal immunoglobulin G4 antibody targeting ß-amyloid oligomers, in participants with prodromal to mild (early) AD. Design, Setting, and Participants: Two phase 3 multicenter randomized double-blind placebo-controlled parallel-group efficacy and safety studies of crenezumab in participants with early AD, CREAD and CREAD2, were initiated in 2016 and 2017, respectively, and were designed to evaluate the efficacy and safety of crenezumab in participants with early AD. CREAD (194 sites in 30 countries) and CREAD2 (209 sites in 27 countries) were global multicenter studies. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. Both trials enrolled individuals aged 50 to 85 years with early AD. Participants with some comorbidities and evidence of cerebral infarction or more than 4 microbleeds or areas of leptomeningeal hemosiderosis on magnetic resonance imaging were excluded. After 2923 and 2858 were excluded, respectively, 813 participants in CREAD and 806 in CREAD2 were randomly assigned in a 1:1 ratio to either placebo or crenezumab. In the final analysis, there were 409 participants in the placebo group and 404 in the crenezumab group in CREAD and 399 in the placebo group and 407 in the crenezumab group in CREAD2. Data were analyzed up until January 2019 and August 2019, respectively. Interventions: Participants received placebo or 60 mg/kg crenezumab intravenously every 4 weeks for up to 100 weeks. Main Outcomes and Measures: The primary outcome was change from baseline to week 105 in Clinical Dementia Rating-Sum of Boxes (CDR-SB) score. Results: There were 813 participants in CREAD (mean [SD] age, 70.7 [8.2] years; 483 female and 330 male) and 806 in CREAD2 (mean [SD] age, 70.9 [7.7] years; 456 female and 350 male). Baseline characteristics were balanced between both groups. The between-group difference in mean change from baseline in CDR-SB score (placebo minus crenezumab) was -0.17 (95% CI, -0.86 to 0.53; P = .63) at week 105 in the CREAD study (88 placebo; 86 crenezumab). Compared with previous trials, no new safety signals were identified, and amyloid-related imaging abnormalities with edema were rare, mild, and transient. No meaningful changes in AD biomarkers were observed. Both studies were discontinued following a preplanned interim analysis indicating that CREAD was unlikely to meet the primary end point. Conclusions and Relevance: Crenezumab was well tolerated but did not reduce clinical decline in participants with early AD. Trial Registration: ClinicalTrials.gov Identifiers: CREAD, NCT02670083; CREAD2, NCT03114657.


Assuntos
Doença de Alzheimer , Anticorpos Monoclonais Humanizados , Adulto , Idoso , Feminino , Humanos , Masculino , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Método Duplo-Cego , Placa Amiloide , Resultado do Tratamento , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico
2.
J Trace Elem Med Biol ; 45: 181-188, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29173477

RESUMO

Abnormal handling of copper is the cause of Wilson disease (WD), a rare disorder typified by increased levels in plasma copper not-bound to ceruloplasmin (nCp-Cu, also known as 'free' copper). In Alzheimer's disease (AD), meta-analyses show that copper decreases in brain but increases in serum, due to the nCp Cu component increase. Despite the similarities, a direct comparison of copper biological status in the two diseases has never been carried out. To fill this gap, we evaluated serum copper, ceruloplasmin, nCp-Cu and Cu:Cp in 385 CE and 336 healthy controls previously investigated that were compared with 9 newly diagnosed WD patients. We then assessed 24h copper urinary excretion in 24 WD patients under D-penicillamine (D-pen) treatment and in 35 healthy controls, and compared results with those of AD patients participating to a D-pen phase II clinical trial previously published. After adjusting for sex and age, serum nCp-Cu and Cu:Cp resulted higher in AD and in WD than in healthy controls (both p<0.001). While nCp-Cu was similar between AD and WD, Cu:Cp was higher in WD (p<0.016). 24h urinary copper excretion in AD patients (12.05µg/day) was higher than in healthy controls (4.82µg/day; p<0.001). 77.8% of the AD patients under D-pen treatment had a 24h urinary excretion higher than 200µg/day, suggestive of a failure of copper control. This study provides new insight into the pathophysiology of copper homeostasis in AD, showing a failure of copper control and the Cu:Cp ratio as an eligible marker.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/urina , Cobre/sangue , Cobre/urina , Degeneração Hepatolenticular/sangue , Degeneração Hepatolenticular/urina , Ceruloplasmina , Feminino , Humanos , Masculino
3.
Curr Alzheimer Res ; 14(12): 1318-1326, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28669331

RESUMO

BACKGROUND: Meta-analyses show that copper non-bound to ceruloplasmin (non-Cp Cu, also known as 'free' copper) in serum is higher in a percentage of Alzheimer's disease (AD) patients. Genetic heterogeneity in AD patients stratified on the basis of non-Cp Cu cut-off sustains the existence of a copper AD metabolic subtype. OBJECTIVE: In order to find evidence of the existence of a detectable metabolic subtype of AD associated to copper abnormalities, we explore the hypothesis of a neuroimaging pattern heterogeneity in an homogenous and well characterized AD population classified in two groups by the stratification of patients on the basis non-Cp Cu cut-off. METHOD: We assessed levels of copper, ceruloplasmin, non-Cp Cu, cerebrospinal levels of total Tau protein (h-tau), Thr 181 phosphorylated tau protein (P-tau) and ß-amyloid 1-42, and APOE4 genotype in 66 AD patients and compared neuroimaging indices of a visual rating scale of cerebral atrophy and neurovascular burden in AD patients stratified in 'Normal' and 'High' non-Cp Cu groups. RESULTS: The stratification for non-Cp Cu originated AD groups which did not differ for medial temporal lobe atrophy, periventricular hyperintensities, deeper hyperintensities (including frontal, parietooccipital and temporal white matter hyperintensities), infratentorial hyperintensities indices, while they differed for global atrophy. More specifically, AD patients within the high non-Cp Cu group had a less severe burden of global atrophy (p=0.042). CONCLUSION: This neuroimaging heterogeneity between AD groups is suggestive of the existence of a copper metabolic subtype of AD; non-Cp Cu appears a good marker of this copper AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Ceruloplasmina/metabolismo , Cobre/metabolismo , Neuroimagem/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Fragmentos de Peptídeos , Proteínas tau/líquido cefalorraquidiano
4.
Clin Chem Lab Med ; 55(9): 1360-1367, 2017 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-28076308

RESUMO

BACKGROUND: Meta-analyses indicated the breakdown of copper homeostasis in the sporadic form of Alzheimer's disease (AD), comprising copper decreases within the brain and copper increases in the blood and the pool not bound to ceruloplasmin (non-Cp Cu, also known in the literature as "free" copper). The calculated non-Cp Cu (Walshe's) index has many limitations. METHODS: A direct fluorescent method for non-Cp Cu detection has been developed and data are presented herein. The study included samples from 147 healthy subjects, 36 stable mild cognitive impairment (MCI) and 89 AD patients, who were tested for non-Cp Cu through the direct method, total serum copper, ceruloplasmin concentration and o-dianisidine ceruloplasmin activity. The indirect non-Cp Cu Walshe's index was also calculated. RESULTS: The direct method was linear (0.9-5.9 µM), precise (within-laboratory coefficient variation of 9.7% for low and 7.1% for high measurements), and had a good recovery. A reference interval (0-1.9 µM) was determined parametrically in 147 healthy controls (27-84 years old). The variation of non-Cp Cu was evaluated according to age and sex. Non-Cp Cu was 1.5 times higher in AD patients (regarding the upper value of the reference interval) than in healthy controls. Healthy, MCI and AD subjects were differentiated through the direct non-Cp Cu method [areas under the curve (AUC)=0.755]. Considering a 95% specificity and a 1.91 µmol/L cut-off, the sensitivity was 48.3% (confidence interval 95%: 38%-58%). The likelihood ratio (LR) was 9.94 for positive test results (LR+) and 0.54 for negative test result (LR-). CONCLUSIONS: The direct fluorescent test reliably and accurately measures non-Cp Cu, thereby determining the probability of having AD.


Assuntos
Doença de Alzheimer/sangue , Cobre/sangue , Corantes Fluorescentes/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Fluorescência
5.
Ann Neurol ; 75(4): 574-80, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24623259

RESUMO

OBJECTIVE: Meta-analyses show that nonbound ceruloplasmin (non-Cp) copper (also known as free or labile copper) in serum is higher in patients with Alzheimer disease (AD). It differentiates subjects with mild cognitive impairment (MCI) from healthy controls. However, a longitudinal study on an MCI cohort has not yet been performed to assess the accuracy of non-Cp copper for the prediction of conversion from MCI to AD during a long-term follow-up. METHODS: The study included 42 MCI converters and 99 stable MCI subjects. We assessed levels of copper, ceruloplasmin, non-Cp copper, iron, transferrin, ferritin, and APOE genotype. A multiple Cox regression analysis-with age, sex, baseline Mini-Mental State Examination, APOE4, iron, non-Cp copper, transferrin, ferritin, hypercholesterolemia, and hypertension as covariates-was applied to predict the conversion from MCI to AD. RESULTS: Among the evaluated parameters, the only significant predictor of conversion to AD was non-Cp copper (hazard ratio = 1.23, 95% confidence interval = 1.03-1.47, p = 0.022); for each additional micromole per liter unit (µmol/l) of non-Cp copper, the hazard increased by ~20%. Subjects with non-Cp copper levels >1.6 µmol/l had a hazard conversion rate (50% of conversion in 4 years) that was ~3× higher than those with values ≤1.6 µmol/l (<20% in 4 years). The rate of conversion was similar between APOE4 carriers and noncarriers (p = 0.321), indicating that the non-Cp copper association was independent of APOE4. INTERPRETATION: Non-Cp copper appears to predict conversion from MCI to AD. These results encourage healthy life style choices and dietary intervention to modify this risk.


Assuntos
Doença de Alzheimer/sangue , Transtornos Cognitivos/sangue , Cobre/sangue , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Ceruloplasmina/metabolismo , Transtornos Cognitivos/genética , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Valor Preditivo dos Testes , Probabilidade , Fatores de Risco
6.
Rejuvenation Res ; 16(1): 3-10, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22950421

RESUMO

Copper dyshomeostasis leading to a labile Cu(2+) not bound to ceruloplasmin ("free" copper) may influence Alzheimer's disease (AD) onset or progression. To investigate this hypothesis, we investigated ATP7B, the gene that controls copper excretion through the bile and concentrations of free copper in systemic circulation. Our study analyzed informative ATP7B single-nucleotide polymorphisms (SNPs) in a case-control population (n=515). In particular, we evaluated the genetic structure of the ATP7B gene using the HapMap database and carried out a genetic association investigation. Linkage disequilibrium (LD) analysis highlighted that our informative SNPs and their LD SNPs covered 96% of the ATP7B gene sequence, distinguishing two "strong LD" blocks. The first LD block contains the gene region encoding for transmembrane and copper-binding, whereas the second LD block encodes for copper-binding domains. The genetic association analysis showed significant results after multiple testing correction for all investigated variants (rs1801243, odds ratio [OR]=1.52, 95% confidence interval [CI]=1.10-2.09, p=0.010; rs2147363, OR=1.58, 95% CI=1.11-2.25, p=0.010; rs1061472, OR=1.73, 95% CI=1.23-2.43, p=0.002; rs732774, OR=2.31, 95% CI=1.41-3.77, p<0.001), indicating that SNPs in transmembrane domains may have a stronger association with AD risk than variants in copper-binding domains. Our study provides novel insights that confirm the role of ATP7B as a potential genetic risk factor for AD. The analysis of ATP7B informative SNPs confirms our previous hypothesis about the absence of ATP7B in the significant loci of genome-wide association studies of AD and the genetic association study suggests that transmembrane and adenosine triphosphate (ATP) domains in the ATP7B gene may harbor variants/haplotypes associated with AD risk.


Assuntos
Adenosina Trifosfatases/genética , Doença de Alzheimer/genética , Proteínas de Transporte de Cátions/genética , Haplótipos , Desequilíbrio de Ligação , ATPases Transportadoras de Cobre , Humanos , Polimorfismo de Nucleotídeo Único
7.
Curr Alzheimer Res ; 10(2): 191-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23036026

RESUMO

The link between biometals and Alzheimer's disease (AD) has been investigated with a focus on local metal accumulations. In this work, we have looked at systemic metal changes and computed a score (M-score) based on metal disarrangements to discriminate patients with AD from patients with vascular dementia (VaD) and from controls. We measured serum levels of iron, copper, ceruloplasmin, transferrin, and total antioxidant capacity (TAS), performed Apolipoprotein E (APOE) genotyping and calculated non-ceruloplasmin copper ('free' copper') levels, transferrin saturation, total iron binding capacity, and ceruloplasmin-transferrin ratio (Cp/Tf) in 93 patients with AD, 45 patients with VaD, and 48 controls. All subjects underwent biochemical, neuroimaging and cognitive evaluations. Significant differences were observed among the tested groups for the levels of copper, free copper, peroxides, and TAS and for the Cp/Tf with disparity in couple comparison. On this basis we created the M-score as linear combination of biometal variables and APOE genotype. Besides its ability to discriminate AD patients vs. controls (ROC AUC=90%), M-score was able to distinguish AD vs. VaD (ROC AUC=79%). Moreover, we calculated the sensitivity and the specificity for M-score and for the other significant variables: M-score reached the highest sensitivity without a relevant loss in terms of specificity. When we compared M-score with APOE genotype and Medial Temporal Atrophy score, it resulted statistically better than these diagnostic markers. In conclusion, we confirm the link between biometals and AD and suggest its potential as diagnostic tool. Further studies may elucidate its potential role as reliable diagnostic test.


Assuntos
Doença de Alzheimer/sangue , Antioxidantes/metabolismo , Demência Vascular/sangue , Metais/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Análise de Variância , Apolipoproteína E4/genética , Ceruloplasmina/metabolismo , Cobre/sangue , Demência Vascular/complicações , Demência Vascular/genética , Feminino , Humanos , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC , Transferrina/metabolismo
8.
Rejuvenation Res ; 16(1): 51-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23216585

RESUMO

Different factors interact to develop neurodegeneration in patients with dementia and other neurodegenerative disorders. Oxidative stress and the ε4 allele of apolipoprotein E (ApoE) are associated with significant alteration in lipid metabolism, in turn connected to a variety of neurodegenerative diseases and aging. Thus, a better understanding of the pathogenetic pathways associated with lipid dyshomeostasis may elucidate the causes of neurodegenerative processes. To address this issue, we evaluated the effects of antioxidant status and APOE genotype on neurodegeneration in patients with dementia of the Alzheimer type (AD), with vascular dementia (VaD), and in elderly healthy controls. Eighty-two AD, 42 VaD patients, and 26 healthy controls were recruited and underwent medial temporal lobe atrophy (MTA) assessment, white matter hyperintensities rating (WMH), serum total antioxidant status assaying (TAS), and APOE genotyping. A logistic regression algorithm applied to our data revealed that a 0.01 mmol/L decrease of TAS concentration increased the probability of MTA by 24% (p=0.038) and that carriers of the APOE ε4 allele showed higher WMH scores (p=0.018), confirming that small variations in antioxidant systems homeostasis are associated with relevant modifications of disease risk. Furthermore, in individuals with analogous TAS values, the presence of the ε4 allele increased the predicted probability of having MTA. These outcomes further sustain the interaction of oxidative stress and APOE genotype to neurodegeneration.


Assuntos
Doença de Alzheimer/patologia , Antioxidantes/metabolismo , Apolipoproteínas E/genética , Demência Vascular/patologia , Predisposição Genética para Doença , Genótipo , Idoso , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Demência Vascular/genética , Demência Vascular/metabolismo , Feminino , Humanos , Masculino
9.
J Neurol Sci ; 317(1-2): 137-40, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22381228

RESUMO

Alzheimer's disease (AD) is the most common form of dementia in the elderly. The causes of AD are very complex but there is general agreement about the existence of a link between Alzheimer's disease and oxidative stress. The Glutathione S-transferases (GSTs) act to detoxify products of oxidation that cause damage to macromolecules. Particular attention has been focused on GST genes because polymorphisms are important determinants of disease risk. To evaluate if GSTA1, GSTM1, GSTP1, and GSTT1 genes are associated with LOAD we screened a case-control population (n=311). Differences in genotype distributions between AD patients and controls were found only for the GSTM1 null genotype (P<0.001). In addition, a logistic regression analysis also conferred a positive association between the GSTM1 null genotype and LOAD after adjustment for age and gender (OR=2.09; 95%CI=1.31-3.35). The GSTM1 enzyme detoxifies substances such as exogenous and endogenous metabolites and plays a regulatory role in cellular signaling. Previous studies have highlighted that GSTM1 has a role in neurodegenerative disorders, but no data have associated the GSTM1 gene with AD risk. Our outcome suggests that the GSTM1 null genotype is a risk factor for AD in Italian patients.


Assuntos
Doença de Alzheimer/enzimologia , Doença de Alzheimer/genética , Glutationa Transferase/genética , População Branca/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Doença de Alzheimer/epidemiologia , Feminino , Genótipo , Humanos , Itália/epidemiologia , Masculino , Fatores de Risco
10.
Neurobiol Aging ; 33(8): 1633-41, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21514009

RESUMO

It is now accepted that transition metals, such as iron and copper, are involved in the pathogenesis of the Alzheimer's disease (AD) through their participation in toxic oxidative phenomena. In this context, hemochromatosis (Hfe) and transferrin (Tf) genes are of particular importance, since they play a key role in iron homeostasis. Also, signs of liver distress which accompany metal dysmetabolisms have been shown to be linked to AD. In order to investigate whether and how all these factors are interconnected, in this study we have explored the relationship of the gene variants of Hfe H63D and C282Y and of Tf C2 with serum markers of iron status (iron, ferritin, TF, TF-saturation, ceruloplasmin -CP-, CP and TF serum concentrations (CP/TF) ratio), and of liver function (albumin, transaminases, prothrombin time-prothrombin time (PT)) in a sample of 160 AD patients and 79 healthy elderly controls. Albumin resulted in lower, PT longer and AST/ALT higher ratios in AD patients than in controls, indicating a distress of the liver. Also TF was lower and ferritin higher in AD. Multiple logistic regression backward analyses, performed to evaluate the effects of our biochemical variables upon the probability of developing AD, revealed that a one-unit TF serum-decrease increases the probability of AD by 80%, a one-unit albumin serum-decrease reduces this probability by 20%, and a one-unit increase of AST/ALT ratio generates a 4-fold probability increase. Patients who were carriers of the H63D mutation showed higher levels of iron, lower levels of TF and CP and higher CP/TF ratios, a panel resembling hemochromatosis. This picture was found neither in H63D non-carrier patients, nor in healthy controls. Our results suggest the existence of a link between Hfe mutations and iron abnormalities that increases the probability of developing AD when accompanied by a distress of the liver.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Hemocromatose/sangue , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Mutação , Transferrina/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Biomarcadores/sangue , Causalidade , Comorbidade , Feminino , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Hemocromatose/epidemiologia , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/sangue , Humanos , Ferro/sangue , Itália/epidemiologia , Hepatopatias , Masculino , Proteínas de Membrana/sangue , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Prevalência , Fatores de Risco , Transferrina/análise
11.
Int J Alzheimers Dis ; 2011: 231595, 2010 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-21234401

RESUMO

The link between iron and Alzheimer's disease (AD) has been mainly investigated with a focus on the local accumulation of this metal in specific areas of the brain that are critical for AD. In the present study, we have instead looked at systemic variations of markers of iron metabolism. We measured serum levels of iron, ceruloplasmin, and transferrin and calculated the transferrin saturation and the ceruloplasmin to transferrin ratio (Cp/Tf). Cp/Tf and transferrin saturation increased in AD patients. Cp/Tf ratios also correlated positively with peroxide levels and negatively with serum iron concentrations. Elevated values of ceruloplasmin, peroxides, and Cp/Tf inversely correlated with MMSE scores. Isolated medial temporal lobe atrophy positively correlated with Cp/Tf and negatively with serum iron. All these findings indicate that the local iron accumulation found in brain areas critical for AD should be viewed in the frame of iron systemic alterations.

12.
J Alzheimers Dis ; 18(2): 295-303, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19584443

RESUMO

A novel missense mutation (T719P) in the amyloid-beta protein precursor (AbetaPP) gene was discovered in a 46-year old patient affected by early onset familial Alzheimer's disease. Using surface enhanced laser desorption/ionization mass spectrometry (SELDI-TOF MS), we determined mass profiles of amyloid-beta peptides (Abeta) in cerebrospinal fluid (CSF) of the AbetaPP mutated patient, healthy control subjects (n = 10), and of two subjects carrying mutations in presenilins genes (PS) (i.e., PS1 P117L and PS2 T122R): seven different C-terminally and three N-terminally truncated Abeta peptides were found in CSF. The investigated AbetaPP as well as PS mutations were associated with an overall reduction of Abeta species, except for Abeta(10-40). Interestingly, the AbetaPP T719P mutation unbalanced the relative proportion of Abeta peptides with a reduction of Abeta(1-40) and Abeta(1-42) paralleled by an increase of Abeta(1-38) and Abeta(10-40). Despite the specific neuropeptidomic phenotype associated with the AbetaPP T719P mutation, the enrichment in Abeta(10-40) paralleled by depletion of Abeta(1-42) seems to be a common theme in familial AD. The AbetaPP T719P mutation is of particular interest because it is the only mutation located in close proximity to the AbetaPP epsilon-cleavage site.


Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Precursor de Proteína beta-Amiloide/genética , Mutação/genética , Treonina/genética , Tirosina/genética , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Fragmentos de Peptídeos/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
13.
Clin Neurophysiol ; 120(4): 709-18, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19324592

RESUMO

OBJECTIVE: Non-steroidal anti-inflammatory drugs such as ibuprofen have a protective role on risk of Alzheimer's disease (AD). Here we evaluated the hypothesis that long-term ibuprofen treatment affects cortical sources of resting electroencephalographic (EEG) rhythms in mild AD patients. METHODS: Twenty-three AD patients (13 treated AD IBUPROFEN; 10 untreated AD PLACEBO) were enrolled. Resting EEG data were recorded before and 1 year after the ibuprofen/placebo treatment. EEG rhythms were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). LORETA was used for EEG source analysis. RESULTS: In the AD PLACEBO group, amplitude of delta sources was globally greater at follow-up than baseline. Instead, amplitude of delta sources remained stable or decreased in the majority of the AD IBUPROFEN patients. Clinical (CDR) but not global cognitive status (MMSE) reflected EEG results. CONCLUSIONS: These results suggest that in mild AD patients, a long-term ibuprofen treatment slightly slows down the progressive increment of delta rhythms as a sign of contrast against the neurodegenerative processes. SIGNIFICANCE: They motivate future investigations with larger population and extended neuropsychological testing, to study the relationships among ibuprofen treatment, delta cortical sources, and higher order functions.


Assuntos
Doença de Alzheimer/fisiopatologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Córtex Cerebral/efeitos dos fármacos , Eletroencefalografia/efeitos dos fármacos , Ibuprofeno/uso terapêutico , Idoso , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Doença de Alzheimer/prevenção & controle , Análise de Variância , Anti-Inflamatórios não Esteroides/farmacologia , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Ibuprofeno/farmacologia , Imageamento Tridimensional , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Testes Neuropsicológicos , Valores de Referência , Análise Espectral
14.
Neurobiol Aging ; 30(1): 93-102, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17573161

RESUMO

Is directionality of electroencephalographic (EEG) synchronization abnormal in amnesic mild cognitive impairment (MCI) and Alzheimer's disease (AD)? EEG data were recorded in 64 normal elderly (Nold), 69 amnesic MCI, and 73 mild AD subjects at rest condition (closed eyes). Direction of information flux within EEG functional coupling at electrode pairs was performed by directed transfer function (DTF) at delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10 Hz), alpha 2 (10-12 Hz), beta 1 (13-20 Hz), beta 2 (20-30 Hz), and gamma (30-40 Hz). Parietal to frontal direction of the information flux within EEG functional coupling was stronger in Nold than in MCI and/or AD subjects, namely for alpha and beta rhythms. In contrast, the directional flow within inter-hemispheric EEG functional coupling did not discriminate among the three groups. These results suggest that directionality of parieto-to-frontal EEG synchronization is abnormal not only in AD but also in amnesic MCI.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Amnésia/diagnóstico , Amnésia/fisiopatologia , Encéfalo/fisiopatologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Idoso , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Feminino , Humanos , Masculino
15.
Brain Res ; 1215: 183-9, 2008 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-18486114

RESUMO

Since many years the apolipoprotein E epsilon4 allele (APOE-epsilon4) is known to be associated with Alzheimer disease (AD) but the mechanisms of these associations remained unclear. In the last years, the potential pathogenetic role of 'free' copper (i.e. non-ceruloplasmin bound copper) has been evidenced in AD. Recently, elevated 'free' copper was found to be correlated with slowing of cortical electroencephalographic (EEG) rhythms. The present work aimed to check the hypothesis that the strength of the correlations between free-copper and alterations of cortical rhythms might be different in carriers and non-carriers of the APOE-epsilon4 allele. Fifty-four AD patients and 20 healthy controls were included in the study. In all of them 1) APOE genotyping was performed; 2) total serum copper and ceruloplasmin was determined in order to calculate the serum 'free' copper; and 3) resting eyes-closed EEG rhythms were recorded and spectral brain activity was estimated via LORETA. A 'two correlation coefficients comparison' test was used to test the strength of the correlation in APOE-epsilon4 carriers and non-carriers. 'Free' copper levels were higher in patients than in controls and correlated positively with parietal-temporal delta and negatively with parieto-temporal alpha-1 activities. The correlation between 'free' copper and temporal alpha-1 activity was stronger in APOE-epsilon4 carriers than in non-carriers. Peroxide levels correlated with higher temporal delta in the AD group. APOE-epsilon4 appears to modulate the effect of copper on the altered AD brain activities, suggesting that modulation of oxidative stress related to copper dysfunction may be one of the mechanisms that make APOE-epsilon4 a risk factor for AD.


Assuntos
Doença de Alzheimer/sangue , Apolipoproteína E4/genética , Cobre/sangue , Lobo Parietal/fisiologia , Lobo Temporal/fisiologia , Idoso , Idoso de 80 Anos ou mais , Ritmo alfa , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Estudos de Casos e Controles , Ceruloplasmina/análise , Distribuição de Qui-Quadrado , Cobre/toxicidade , Ritmo Delta , Feminino , Humanos , Masculino , Lobo Parietal/efeitos dos fármacos , Lobo Parietal/fisiopatologia , Valores de Referência , Estatísticas não Paramétricas , Lobo Temporal/efeitos dos fármacos , Lobo Temporal/fisiopatologia
16.
Hum Mutat ; 29(4): 565, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18330912

RESUMO

Heterozygous rare variants in the PINK1 gene, as well as in other genes causing autosomal recessive parkinsonism, have been reported both in patients and healthy controls. Their pathogenic significance is uncertain, but they have been suggested to represent risk factors to develop Parkinson disease (PD). The few large studies that assessed the frequency of PINK1 heterozygotes in cases and controls yielded controversial results, and the phenotypic spectrum is largely unknown. We retrospectively analyzed the occurrence of PINK1 heterozygous rare variants in over 1100 sporadic and familial patients of all onset ages and in 400 controls. Twenty patients and 6 controls were heterozygous, with frequencies (1.8% vs. 1.5%) not significantly different in the two groups. Clinical features of heterozygotes were indistinguishable to those of wild-type patients, with mean disease onset 10 years later than in carriers of two mutations but worse disease progression. A meta-analysis indicated that, in PINK1 heterozygotes, the PD risk is only slightly increased with a non significant odds ratio of 1.62. These findings suggest that PINK1 heterozygous rare variants play only a minor susceptibility role in the context of a multifactorial model of PD. Hence, their significance should be kept distinct from that of homozygous/compound heterozygous mutations, that cause parkinsonism inherited in a mendelian fashion.


Assuntos
Variação Genética , Doença de Parkinson/genética , Proteínas Quinases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genes Recessivos , Heterozigoto , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Doença de Parkinson/enzimologia , Fenótipo , Estudos Retrospectivos , Homologia de Sequência de Aminoácidos
17.
Biometals ; 21(3): 367-72, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18060472

RESUMO

The level of the apo-form of the copper enzyme ceruloplasmin (CP) is an established peripheral marker in diseases associated with copper imbalance. In view of the proposal that disturbances of copper homeostasis may contribute to neurodegeneration associated with Alzheimer's disease (AD), the present work investigates, by Western blot and non-reducing SDS-PAGE followed by activity staining, the features of CP protein, and the copper/CP relationship in cerebrospinal fluid (CSF) and serum of AD patients. Results show that only a fraction of total copper is associated with CP in the CSF, at variance with serum, both in affected and in healthy individuals. Furthermore, a conspicuous amount of apo-ceruloplasmin and a decrease of CP oxidase activity characterize the CSF of the affected individuals, and confirm that an impairment of copper metabolism occurs in their central nervous system. In the CSF of AD patients the decrease of active CP, associated with the increase in the pool of copper not sequestered by this protein, may play a role in the neurodegenerative process.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Ceruloplasmina/líquido cefalorraquidiano , Idoso , Ceruloplasmina/metabolismo , Feminino , Holoenzimas/metabolismo , Humanos , Masculino
18.
Eur J Neurosci ; 25(12): 3742-57, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17610594

RESUMO

Previous evidence has shown that resting delta and alpha electroencephalographic (EEG) rhythms are abnormal in patients with Alzheimer's disease (AD) and its potential preclinical stage (mild cognitive impairment, MCI). Here, we tested the hypothesis that these EEG rhythms are correlated with memory and attention in the continuum across MCI and AD. Resting eyes-closed EEG data were recorded in 34 MCI and 53 AD subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by low-resolution brain electromagnetic tomography (LORETA). These sources were correlated with neuropsychological measures such as Rey list immediate recall (word short-term memory), Rey list delayed recall (word medium-term memory), Digit span forward (immediate memory for digits probing focused attention), and Corsi span forward (visuo-spatial immediate memory probing focused attention). A statistically significant negative correlation (Bonferroni corrected, P < 0.05) was observed between Corsi span forward score and amplitude of occipital or temporal delta sources across MCI and AD subjects. Furthermore, a positive correlation was shown between Digit span forward score and occipital alpha 1 sources (Bonferroni corrected, P < 0.05). These results suggest that cortical sources of resting delta and alpha rhythms correlate with neuropsychological measures of immediate memory based on focused attention in the continuum of MCI and AD subjects.


Assuntos
Doença de Alzheimer/fisiopatologia , Atenção/fisiologia , Transtornos Cognitivos/fisiopatologia , Eletroencefalografia , Descanso , Idoso , Doença de Alzheimer/patologia , Análise de Variância , Mapeamento Encefálico , Estudos de Casos e Controles , Córtex Cerebral/fisiopatologia , Transtornos Cognitivos/patologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Tempo de Reação/fisiologia
19.
Clin Neurophysiol ; 118(6): 1244-60, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17462944

RESUMO

OBJECTIVE: The present study tested the hypothesis that the serum copper abnormalities were correlated with alterations of resting electroencephalographic (EEG) rhythms across the continuum of healthy elderly (Hold), mild cognitive impairment (MCI), and AD subjects. METHODS: Resting eyes-closed EEG rhythms delta (2-4Hz), theta (4-8Hz), alpha 1 (8-10.5Hz), alpha 2 (10.5-13Hz), beta 1 (13-20Hz), beta 2 (20-30Hz), and gamma (30-40Hz), estimated by LORETA, were recorded in 17 Hold, 19 MCI, 27 AD- (MMSE< or =20), and 27 AD+ (MMSE20) individuals and correlated with copper biological variables. RESULTS: Across the continuum of Hold, MCI and AD subjects, alpha sources in parietal, occipital, and temporal areas were decreased, while the magnitude of the delta and theta EEG sources in parietal, occipital, and temporal areas was increased. The fraction of serum copper unbound to ceruloplasmin positively correlated with temporal and frontal delta sources, regardless of the effects of age, gender, and education. CONCLUSIONS: These results sustain the hypothesis of a toxic component of serum copper that is correlated with functional loss of AD, as revealed by EEG indexes. SIGNIFICANCE: The present study represents the first demonstration that the fraction of serum copper unbound to ceruloplasmin is correlated with cortical delta rhythms across Hold, MCI, and AD subjects, thus unveiling possible relationships among the biological parameter, advanced neurodegenerative processes, and synchronization mechanisms regulating the relative amplitude of selective EEG rhythms.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/fisiopatologia , Transtornos Cognitivos/sangue , Transtornos Cognitivos/fisiopatologia , Cobre/sangue , Eletroencefalografia , Descanso/fisiologia , Idoso , Análise de Variância , Betaxolol , Mapeamento Encefálico , Ceruloplasmina/metabolismo , Eletroencefalografia/classificação , Feminino , Humanos , Masculino , Tomografia
20.
Neuroimage ; 31(4): 1650-65, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16600641

RESUMO

Acetylcholinesterase inhibitors (AChEI) such as donepezil act in mild Alzheimer's disease (AD) by increasing cholinergic tone. Differences in the clinical response in patients who do or do not benefit from therapy may be due to different functional features of the central neural systems. We tested this hypothesis using cortical electroencephalographic (EEG) rhythmicity. Resting eyes-closed EEG data were recorded in 58 mild AD patients (Mini Mental State Examination [MMSE] range 17-24) before and approximately 1 year after standard donepezil treatment. Based on changes of MMSE scores between baseline and follow-up, 28 patients were classified as "Responders" (MMSEvar >or=0) and 30 patients as "Non-Responders" (MMSEvar <0). EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). Cortical EEG sources were studied with low-resolution brain electromagnetic tomography (LORETA). Before treatment, posterior sources of delta, alpha 1 and alpha 2 frequencies were greater in amplitude in Non-Responders. After treatment, a lesser magnitude reduction of occipital and temporal alpha 1 sources characterized Responders. These results suggest that Responders and Non-Responders had different EEG cortical rhythms. Donepezil could act by reactivating existing yet functionally silent cortical synapses in Responders, restoring temporal and occipital alpha rhythms.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/fisiopatologia , Córtex Cerebral/fisiopatologia , Eletroencefalografia/efeitos dos fármacos , Indanos/uso terapêutico , Magnetoencefalografia/efeitos dos fármacos , Nootrópicos/uso terapêutico , Piperidinas/uso terapêutico , Idoso , Mapeamento Encefálico , Interpretação Estatística de Dados , Donepezila , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica
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