RESUMEN
COVID-19 remains a serious concern for elderly individuals with underlying comorbidities. SARS-CoV-2 can target and damage mitochondria, potentially leading to mutations in mitochondrial DNA (mtDNA). This study aimed to evaluate single nucleotide substitutions in mtDNA and analyze their correlation with inflammatory biomarkers in elderly COVID-19 patients. A total of 30 COVID-19 patients and 33 older adult controls without COVID-19 (aged over 65 years) were enrolled. mtDNA was extracted from buffy coat samples and sequenced using a chip-based resequencing system (MitoChip v2.0) which detects both homoplasmic and heteroplasmic mtDNA variants (40-60% heteroplasmy), and allows the assessment of low-level heteroplasmy (<10% heteroplasmy). Serum concentrations of IL-6, IFN-α, TNF-α and IL-10 were determined in patients by a high-sensitivity immunoassay. We found a higher burden of total heteroplasmic variants in COVID-19 patients compared to controls with a selective increment in ND1 and COIII genes. Low-level heteroplasmy was significantly elevated in COVID-19 patients, especially in genes of the respiratory complex I. Both heteroplasmic variant burden and low-level heteroplasmy were associated with increased levels of IL-6, TNF-α, and IFN-α. These findings suggest that SARS-CoV-2 may induce mtDNA mutations that are related to the degree of inflammation.
RESUMEN
BACKGROUND: ALS is a heterogeneous disease in which different factors such as mitochondrial phenotypes act in combination with a genetic predisposition. This study addresses the question of whether homoplasmic (total mitochondrial genome of a sample is affected) and/or heteroplasmic mutations (wildtype and mutant mitochondrial DNA molecules coexist) might play a role in familial ALS. Blood was drawn from familial ALS patients with a possible maternal pattern of inheritance according to their pedigrees, which was compared to blood of ALS patients without maternal association as well as age-matched controls. In two cohorts, we analyzed the mitochondrial genome from whole blood or isolated white blood cells and platelets using a resequencing microarray (Affymetrix MitoChip v2.0) that is able to detect homoplasmic and heteroplasmic mitochondrial DNA mutations and allows the assessment of low-level heteroplasmy. RESULTS: We identified an increase in homoplasmic ND5 mutations, a subunit of respiratory chain complex I, in whole blood of ALS patients that allowed maternal inheritance. This effect was more pronounced in patients with bulbar onset. Heteroplasmic mutations were significantly increased in different mitochondrial genes in platelets of patients with possible maternal inheritance. No increase of low-level heteroplasmy was found in maternal ALS patients. CONCLUSION: Our results indicate a contribution of homoplasmic ND5 mutations to maternally associated ALS with bulbar onset. Therefore, it might be conceivable that specific maternally transmitted rather than randomly acquired mitochondrial DNA mutations might contribute to the disease process. This stands in contrast with observations from Alzheimer's and Parkinson's diseases showing an age-dependent accumulation of unspecific mutations in mitochondrial DNA.
Asunto(s)
Esclerosis Amiotrófica Lateral , Genoma Mitocondrial , Humanos , Genoma Mitocondrial/genética , Herencia Materna/genética , Esclerosis Amiotrófica Lateral/genética , ADN Mitocondrial/genética , Mitocondrias/genética , MutaciónRESUMEN
BACKGROUND: Numerous mouse models of Alzheimer's disease (AD) are available, but all suffer from certain limitations, thus prompting further attempts. To date, no one model exists with amyloidopathy in a BALB/c strain. OBJECTIVE: To generate and characterize the C.B6/J-APPswe mouse, a model of AD with a mutated human gene for the amyloid-ß protein precursor (AßPP) inserted in a BALB/c background. METHODS: We analyzed five groups at different ages (3, 6, 9, 12, and 16-18 months) of C.B6/J-APPswe and wild-type mice (50% males and 50% females) for the main hallmarks of AD by western blotting, amyloid-ß (Aß) ELISA, immunocytochemistry, electrophysiology, and behavioral tests. RESULTS: The C.B6/J-APPswe mouse displays early AßPP and Aß production, late amyloid plaques formation, high level of Tau phosphorylation, synaptic deficits (reduced density and functional impairment due to a reduced post-synaptic responsiveness), neurodegeneration caused by apoptosis and necroptosis/necrosis, microgliosis, astrocytic abnormalities, and sex-related differences in explorative behavior, anxiety-like behavior, and spatial long-term and working memories. Social housing is feasible despite the intra-cage aggressiveness of male animals. CONCLUSION: C.B6/J-APPswe mice develop most of the distinctive features of AD and is a suitable model for the study of brain atrophy mechanisms and of the differences between males and females in the onset of cognitive/non-cognitive deficits.
Asunto(s)
Enfermedad de Alzheimer , Femenino , Ratones , Masculino , Humanos , Animales , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Modelos Animales de Enfermedad , Ratones Transgénicos , Péptidos beta-Amiloides/metabolismoRESUMEN
Herpesviridae reactivation such as cytomegalovirus (CMV) has been described in severe COVID-19 (COronaVIrusDisease-2019). This study aimed to understand if CMV reactivation in older COVID-19 patients is associated with increased inflammation and in-hospital mortality. In an observational single-center cohort study, 156 geriatric COVID-19 patients were screened for CMV reactivation by RT-PCR. Participants underwent a comprehensive clinical investigation that included medical history, functional evaluation, laboratory tests and cytokine assays (TNF-α, IFN-α, IL-6, IL-10) at hospital admission. In 19 (12.2%) of 156 COVID-19 patients, CMV reactivation was detected. Multivariate Cox regression models showed that in-hospital mortality significantly increased among CMV positive patients younger than 87 years (HR: 9.94, 95% CI: 1.66-59.50). Other factors associated with in-hospital mortality were C-reactive protein (HR: 1.17, 95% CI: 1.05-1.30), neutrophil count (HR: 1.20, 95% CI: 1.01-1.42) and clinical frailty scale (HR:1.54, 95% CI: 1.04-2.28). In patients older than 87 years, neutrophil count (HR: 1.13, 95% CI: 1.05-1.21) and age (HR: 1.15, 95% CI: 1.01-1.31) were independently associated with in-hospital mortality. CMV reactivation was also correlated with increased IFN-α and TNF-α serum levels, but not with IL-6 and IL-10 serum changes. In conclusion, CMV reactivation was an independent risk factor for in-hospital mortality in COVID-19 patients younger than 87 years old, but not in nonagenarians.
Asunto(s)
COVID-19 , Infecciones por Citomegalovirus , Anciano de 80 o más Años , Humanos , Anciano , Citomegalovirus/fisiología , Infecciones por Citomegalovirus/complicaciones , Interleucina-10 , Estudios de Cohortes , Interleucina-6 , Factor de Necrosis Tumoral alfa , COVID-19/complicaciones , Activación Viral , Estudios RetrospectivosRESUMEN
(1) Background: During the COVID-19 pandemic, rapid and reliable diagnostic tools are needed for detecting SARS-CoV-2 infection in urgent cases at admission to the hospital. We aimed to assess the performances of the rapid molecular VitaPCR™ test (Menarini Diagnostics) in a sample of older adults admitted to the Emergency Department of two Italian hospitals (2) Methods: The comparison between the rapid VitaPCR™ and the RT-PCR was performed in 1695 samples. Two naso-pharyngeal swab samplings from each individual were obtained and processed using the VitaPCR™ and the RT-PCR for the detection of SARS-CoV-2 (3) Results: VitaPCR™ exhibited good precision (<3% CV) and an almost perfect overall agreement (Cohen's K = 0.90) with the RT-PCR. The limit of detection of the VitaPCR™ was 4.1 copies/µL. Compared to the RT-PCR, the sensitivity, the specificity, and the positive and negative predictive values of VitaPCR™ were 83.4%, 99.9%, 99.2% and 98.3%, respectively (4) Conclusions: The VitaPCR™ showed similar sensitivity and specificity to other molecular-based rapid tests. This study suggests that the VitaPCR™ can allow the rapid management of patients within the Emergency Department. Nevertheless, it is advisable to obtain a negative result by a RT-PCR assay before admitting a patient to a regular ward.
Asunto(s)
COVID-19 , Humanos , Anciano , COVID-19/diagnóstico , SARS-CoV-2/genética , Pandemias , Prueba de COVID-19 , Sensibilidad y Especificidad , Servicio de Urgencia en HospitalRESUMEN
The infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be the cause of a fatal disease known as coronavirus disease 2019 (COVID-19) affecting the lungs and other organs. Particular attention has been given to the effects of the infection on the brain due to recurring neurological symptoms associated with COVID-19, such as ischemic or hemorrhagic stroke, encephalitis and myelitis, which are far more severe in the elderly compared to younger patients. The specific vulnerability of the aged brain could derive from the impaired immune defenses, from any of the altered homeostatic mechanisms that contribute to the aging phenotype, and from particular changes in the aged brain involving neurons and glia. While neuronal modifications could contribute indirectly to the damage induced by SARS-CoV-2, glia alterations could play a more direct role, as they are involved in the immune response to viral infections. In aged patients, changes regarding glia include the accumulation of dystrophic forms, reduction of waste removal, activation of microglia and astrocytes, and immunosenescence. It is plausible to hypothesize that SARS-CoV-2 infection in the elderly may determine severe brain damage because of the frail phenotype concerning glial cells.
Asunto(s)
COVID-19 , Encefalitis , Anciano , Encéfalo , Humanos , Morbilidad , SARS-CoV-2RESUMEN
Alzheimer's disease (AD) has no cure, mainly because of late diagnosis. Early diagnostic biomarkers are crucial. Phospholipases A2 (PLA2) are hydrolases with several functions in the brain, nevertheless their deregulation contributes to neurodegeneration. We evaluated platelet total PLA2 activity (ptotPLA2) in healthy elderly subjects (HE, n = 102), patients suffering from mild cognitive impairment (MCI, n = 90) and AD (n = 91). Platelets are considered "circulating neurons" and ptotPLA2 appears to mirror the cerebral activity. ptotPLA2 of the three cohorts was similar, but in MCI the higher ptotPLA2 the worse the global cognitive status (Mini Mental State Examination score [MMSE]) and in AD the lower ptotPLA2 the more severe the pathology stage (Clinical Dementia Rating [CDR]). Accordingly, MCI with MMSE ≥26 overlapped HE, in MCI with MMSE <26 and in AD with CDR 1 ptotPLA2 increased, in AD with CDR 2 ptotPLA2 decreased. In MCI ptotPLA2 positively correlated with blood oxidation and inflammation, in AD it was the opposite. Finally, Discrimination Index (DI)-calculated multiplying ptotPLA2, oxidative level and Cu/Zn ratio (an inflammation parameter)-differentiated MCI patients who progressed to dementia in the following 24 months and AD patients with the worse pathology development. Summarizing, ptotPLA2 changes during MCI and AD progression, is linked, in opposite way, to oxidative/inflammatory status in MCI and AD and might help, when included in DI, to identify MCI converters to dementia and AD patients with the more severe prognosis. ptotPLA2 may have a diagnostic/prognostic value and be a potential therapeutic target.
Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Fosfolipasas A2/metabolismo , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Biomarcadores , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Cobre/sangre , Progresión de la Enfermedad , Humanos , Estrés Oxidativo , Zinc/sangreRESUMEN
BACKGROUND: Dementia is a syndrome that comprises many differing pathologies, including Alzheimer's disease dementia (ADD), vascular dementia (VaD) and frontotemporal dementia (FTD). People may benefit from knowing the type of dementia they live with, as this could inform prognosis and may allow for tailored treatment. Beta-amyloid (1-42) (ABeta42) is a protein which decreases in both the plasma and cerebrospinal fluid (CSF) of people living with ADD, when compared to people with no dementia. However, it is not clear if changes in ABeta42 are specific to ADD or if they are also seen in other types of dementia. It is possible that ABeta42 could help differentiate ADD from other dementia subtypes. OBJECTIVES: To determine the accuracy of plasma and CSF ABeta42 for distinguishing ADD from other dementia subtypes in people who meet the criteria for a dementia syndrome. SEARCH METHODS: We searched MEDLINE, and nine other databases up to 18 February 2020. We checked reference lists of any relevant systematic reviews to identify additional studies. SELECTION CRITERIA: We considered cross-sectional studies that differentiated people with ADD from other dementia subtypes. Eligible studies required measurement of participant plasma or CSF ABeta42 levels and clinical assessment for dementia subtype. DATA COLLECTION AND ANALYSIS: Seven review authors working independently screened the titles and abstracts generated by the searches. We collected data on study characteristics and test accuracy. We used the second version of the 'Quality Assessment of Diagnostic Accuracy Studies' (QUADAS-2) tool to assess internal and external validity of results. We extracted data into 2 x 2 tables, cross-tabulating index test results (ABeta42) with the reference standard (diagnostic criteria for each dementia subtype). We performed meta-analyses using bivariate, random-effects models. We calculated pooled estimates of sensitivity, specificity, positive predictive values, positive and negative likelihood ratios, and corresponding 95% confidence intervals (CIs). In the primary analysis, we assessed accuracy of plasma or CSF ABeta42 for distinguishing ADD from other mixed dementia types (non-ADD). We then assessed accuracy of ABeta42 for differentiating ADD from specific dementia types: VaD, FTD, dementia with Lewy bodies (DLB), alcohol-related cognitive disorder (ARCD), Creutzfeldt-Jakob disease (CJD) and normal pressure hydrocephalus (NPH). To determine test-positive cases, we used the ABeta42 thresholds employed in the respective primary studies. We then performed sensitivity analyses restricted to those studies that used common thresholds for ABeta42. MAIN RESULTS: We identified 39 studies (5000 participants) that used CSF ABeta42 levels to differentiate ADD from other subtypes of dementia. No studies of plasma ABeta42 met the inclusion criteria. No studies were rated as low risk of bias across all QUADAS-2 domains. High risk of bias was found predominantly in the domains of patient selection (28 studies) and index test (25 studies). The pooled estimates for differentiating ADD from other dementia subtypes were as follows: ADD from non-ADD: sensitivity 79% (95% CI 0.73 to 0.85), specificity 60% (95% CI 0.52 to 0.67), 13 studies, 1704 participants, 880 participants with ADD; ADD from VaD: sensitivity 79% (95% CI 0.75 to 0.83), specificity 69% (95% CI 0.55 to 0.81), 11 studies, 1151 participants, 941 participants with ADD; ADD from FTD: sensitivity 85% (95% CI 0.79 to 0.89), specificity 72% (95% CI 0.55 to 0.84), 17 studies, 1948 participants, 1371 participants with ADD; ADD from DLB: sensitivity 76% (95% CI 0.69 to 0.82), specificity 67% (95% CI 0.52 to 0.79), nine studies, 1929 participants, 1521 participants with ADD. Across all dementia subtypes, sensitivity was greater than specificity, and the balance of sensitivity and specificity was dependent on the threshold used to define test positivity. AUTHORS' CONCLUSIONS: Our review indicates that measuring ABeta42 levels in CSF may help differentiate ADD from other dementia subtypes, but the test is imperfect and tends to misdiagnose those with non-ADD as having ADD. We would caution against the use of CSF ABeta42 alone for dementia classification. However, ABeta42 may have value as an adjunct to a full clinical assessment, to aid dementia diagnosis.
Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/sangre , Péptidos beta-Amiloides/líquido cefalorraquídeo , Fragmentos de Péptidos/sangre , Fragmentos de Péptidos/líquido cefalorraquídeo , Alcoholismo/complicaciones , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/líquido cefalorraquídeo , Sesgo , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Disfunción Cognitiva/sangre , Disfunción Cognitiva/líquido cefalorraquídeo , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Intervalos de Confianza , Síndrome de Creutzfeldt-Jakob/sangre , Síndrome de Creutzfeldt-Jakob/líquido cefalorraquídeo , Síndrome de Creutzfeldt-Jakob/diagnóstico , Demencia Vascular/sangre , Demencia Vascular/líquido cefalorraquídeo , Demencia Vascular/diagnóstico , Diagnóstico Diferencial , Demencia Frontotemporal/sangre , Demencia Frontotemporal/líquido cefalorraquídeo , Demencia Frontotemporal/diagnóstico , Humanos , Hidrocéfalo Normotenso/sangre , Hidrocéfalo Normotenso/líquido cefalorraquídeo , Hidrocéfalo Normotenso/diagnóstico , Enfermedad por Cuerpos de Lewy/sangre , Enfermedad por Cuerpos de Lewy/líquido cefalorraquídeo , Enfermedad por Cuerpos de Lewy/diagnóstico , Funciones de Verosimilitud , Sensibilidad y EspecificidadRESUMEN
In patients with Alzheimer's disease (AD), synaptic plasticity seems to be involved in cognitive improvement induced by cognitive training. The platelet amyloid precursor protein (APP) ratio (APPr), i.e., the ratio between two APP isoforms, may be a useful peripheral biomarker to investigate synaptic plasticity pathways. This study evaluates the changes in neuropsychological/cognitive performance and APPr induced by cognitive training in AD patients participating in the "My Mind Project". Neuropsychological/cognitive variables and APPr were evaluated in the trained group (n = 28) before a two-month experimental protocol, immediately after its termination at follow-up 1 (FU1), after 6 months at follow-up 2 (FU2), and after 24 months at follow-up 3 (FU3). The control group (n = 31) received general psychoeducational training for two months. Some memory and attention parameters were significantly improved in trained vs. control patients at FU1 and FU2 compared to baseline (Δ values). At FU3, APPr and Mini Mental State Examination (MMSE) scores decreased in trained patients. Δ APPr correlated significantly with the Δ scores of (i) MMSE at FU1, (ii) the prose memory test at FU2, and (iii) Instrumental Activities of Daily Living (IADL), the semantic word fluency test, Clinical Dementia Rating (CDR), and the attentive matrices test at FU3. Our data demonstrate that the platelet APPr correlates with key clinical variables, thereby proving that it may be a reliable biomarker of brain function in AD patients.
Asunto(s)
Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Cognición , Actividades Cotidianas , Anciano , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Biomarcadores/metabolismo , Plaquetas/metabolismo , Plaquetas/patología , Femenino , Humanos , Masculino , Memoria , Plasticidad NeuronalRESUMEN
Increasing evidence implicates mitochondrial dysfunction in the etiology of Parkinson's disease (PD). Mitochondrial DNA (mtDNA) mutations are considered a possible cause and this mechanism might be shared with the aging process and with other age-related neurodegenerative disorders such as Alzheimer's disease (AD). We have recently proposed a computerized method for mutated mtDNA characterization able to discriminate between AD and aging. The present study deals with mtDNA mutation-based profiling of PD. Peripheral blood mtDNA sequences from late-onset PD patients and age-matched controls were analyzed and compared to the revised Cambridge Reference Sequence (rCRS). The chaos game representation (CGR) method, modified to visualize heteroplasmic mutations, was used to display fractal properties of mtDNA sequences and fractal lacunarity analysis was applied to quantitatively characterize PD based on mtDNA mutations. Parameter ß, from the hyperbola model function of our lacunarity method, was statistically different between PD and control groups when comparing mtDNA sequence frames corresponding to GenBank np 5713-9713. Our original method, based on CGR and lacunarity analysis, represents a useful tool to analyze mtDNA mutations. Lacunarity parameter ß is able to characterize individual mutation profile of mitochondrial genome and could represent a promising index to discriminate between PD and aging.
Asunto(s)
Envejecimiento , Biomarcadores/análisis , ADN Mitocondrial/genética , Fractales , Enfermedad de Parkinson/genética , Anciano , Anciano de 80 o más Años , Algoritmos , Enfermedad de Alzheimer/genética , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Mitocondrias/genética , Mutación , Dinámicas no Lineales , Análisis de Secuencia por Matrices de Oligonucleótidos , Enfermedad de Parkinson/fisiopatología , ARN Mensajero/genéticaRESUMEN
Availability of reliable prognostic biomarkers that are also able to monitor preventive/therapeutic interventions in patients with mild cognitive impairment (MCI) is crucial. Cerebral brain-derived neurotrophic factor (BDNF) alterations were evidenced in Alzheimer's disease, but the value of blood BDNF in MCI is unclear, especially because of the incomplete/incorrect management of the numerous confounding factors unrelated to the disease. This study, applying a multidisciplinary methodological approach, aimed at clarifying whether blood BDNF can really mirror the cognitive symptoms of MCI, thus supporting the evaluation of clinical protocols' effectiveness as well as the definition of the conversion rate to dementia. Healthy elderly subjects (HE) and MCI patients were assessed for sociodemographic, neuropsychological, pharmacological, and lifestyle data, and plasma BDNF was measured (baseline); then, in the MCI cohort, the biomarker was tested in a comprehensive cognitive stimulation intervention (CS) as well as in a 2-year follow-up period. Plasma BDNF, cleansed from all the interfering factors, (1) did not discriminate HE and MCI patients; (2) in MCI patients reflected mood, social engagement, and subjective memory complaints but not cognition; (3) changed due to CS, although with no correlations to cognitive performances; and (4) predicted no functional deterioration. Our data indicate that the possible biased use of plasma BDNF in MCI is critically risky.
Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Factor Neurotrófico Derivado del Encéfalo , Disfunción Cognitiva , Anciano , Biomarcadores/análisis , Factor Neurotrófico Derivado del Encéfalo/análisis , Disfunción Cognitiva/diagnóstico , Progresión de la Enfermedad , Humanos , Pruebas NeuropsicológicasRESUMEN
BACKGROUND: Mitochondrial DNA (mtDNA) mutations are considered as a possible primary cause of age-associated neurodegenerative disorders like Parkinson's disease (PD). AIMS: To analyze, along the whole mtDNA sequence of PD patients, the presence of non-reference alleles compared to reference alleles, as defined in the revised Cambridge Reference Sequence (rCRS). METHODS: mtDNA was extracted from whole blood of PD and control groups, and was sequenced using a chip-based resequencing system. RESULTS: 58 nucleotide positions (np) exhibited a different allelic distribution in the two groups; in 81% of them the non-reference alleles were over-represented in PD patients, similar to findings reported in patients with Alzheimer's disease, albeit in reduced proportion. Closer analysis of the 58 np in PD group showed that they were characterized by low-level heteroplasmy, and that the nucleotide substitutions determined an amino acid change in 84% of cases. CONCLUSIONS: These results suggest that mtDNA allelic changes are increased in PD and that age-related neurodegenerative diseases could share a common mechanism involving mtDNA.
Asunto(s)
ADN Mitocondrial/genética , Mitocondrias , Enfermedad de Parkinson/genética , Anciano , Anciano de 80 o más Años , Alelos , Femenino , Humanos , Masculino , Mitocondrias/metabolismo , MutaciónAsunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/diagnóstico , Biomarcadores/sangre , Cognición , Demencia Frontotemporal/líquido cefalorraquídeo , Demencia Frontotemporal/diagnóstico , Anciano , Enfermedad de Alzheimer/fisiopatología , Biomarcadores/líquido cefalorraquídeo , Diagnóstico Diferencial , Femenino , Demencia Frontotemporal/fisiopatología , Humanos , Masculino , Curva ROCRESUMEN
The identification of diagnostic-prognostic biomarkers of dementia has become a global priority due to the prevalence of neurodegenerative diseases in aging populations. The objective of this study was to assess the diagnostic performance of cerebrospinal fluid (CSF) biomarkers across patients affected by either Alzheimer's disease (AD), tauopathies other than AD (TP), or vascular dementia (VD), and cognitively normal subjects (CNS). One hundred fifty-three patients were recruited and tested for classical AD CSF biomarkers- Amyloid-ß42 and tau proteins - and novel candidate biomarkers - neurofilament (NF-) light and microRNA (miR) -21, -125b, -146a, and -222.All dementia patients had significantly higher concentrations of NF-light compared to CNS, with the TP group displaying the highest NF-light values. A significant inverse correlation was also observed between NF-light and cognitive impairment. Of the four miRNAs analyzed, miR-222 levels were significantly increased in VD patients compared to both CNS and AD. In addition, while NF-light showed a better diagnostic performance than miR-222 and classical AD biomarkers in differentiating TP and VD from CNS, classical AD biomarkers revealed higher performance in discriminating AD from non-AD disorders.Overall, our results suggest that CSF NF-light and miR-222 are promising biomarkers that may help to diagnose non-AD disorders.
Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/líquido cefalorraquídeo , Demencia Vascular/diagnóstico , Proteínas de Neurofilamentos/líquido cefalorraquídeo , Fragmentos de Péptidos/líquido cefalorraquídeo , Tauopatías/diagnóstico , Proteínas tau/líquido cefalorraquídeo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Demencia Vascular/líquido cefalorraquídeo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tauopatías/líquido cefalorraquídeoRESUMEN
Alzheimer's disease (AD) represents one major health concern for our growing elderly population. It accounts for increasing impairment of cognitive capacity followed by loss of executive function in late stage. AD pathogenesis is multifaceted and difficult to pinpoint, and understanding AD etiology will be critical to effectively diagnose and treat the disease. An interesting hypothesis concerning AD development postulates a cause-effect relationship between accumulation of mitochondrial DNA (mtDNA) mutations and neurodegenerative changes associated with this pathology. Here we propose a computerized method for an easy and fast mtDNA mutations-based characterization of AD. The method has been built taking into account the complexity of living being and fractal properties of many anatomic and physiologic structures, including mtDNA. Dealing with mtDNA mutations as gaps in the nucleotide sequence, fractal lacunarity appears a suitable tool to differentiate between aging and AD. Therefore, Chaos Game Representation method has been used to display DNA fractal properties after adapting the algorithm to visualize also heteroplasmic mutations. Parameter ß from our fractal lacunarity method, based on hyperbola model function, has been measured to quantitatively characterize AD on the basis of mtDNA mutations. Results from this pilot study to develop the method show that fractal lacunarity parameter ß of mtDNA is statistically different in AD patients when compared to age-matched controls. Fractal lacunarity analysis represents a useful tool to analyze mtDNA mutations. Lacunarity parameter ß is able to characterize individual mutation profile of mitochondrial genome and appears a promising index to discriminate between AD and aging.
RESUMEN
BACKGROUND: Astaxanthin (Ax) is a ketocarotenoid of the xanthophyll family with activities such as antioxidation, preservation of the integrity of cell membranes and protection of the redox state and functional integrity of mitochondria. The aim of this study was to investigate potential gender-related differences in the effect of Ax on the aging rat brain. RESULTS: In females, interleukin 1 beta (IL1ß) was significantly lower in treated rats in both cerebral areas, and in the cerebellum, treated animals also had significantly higher IL10. In males, no differences were found in the cerebellum, but in the hippocampus, IL1ß and IL10 were significantly higher in treated rats. CONCLUSION: These are the first results to show gender-related differences in the effect of Ax on the aging brain, emphasizing the necessity to carefully analyze female and male peculiarities when the anti-aging potentialities of this ketocarotenoid are evaluated. The observations lead to the hypothesis that Ax exerts different anti-inflammatory effects in female and male brains.
Asunto(s)
Envejecimiento/fisiología , Encéfalo/efectos de los fármacos , Inflamación/metabolismo , Interleucina-10/análisis , Interleucina-1beta/análisis , Animales , Encéfalo/metabolismo , Química Encefálica/efectos de los fármacos , Cerebelo/química , Cerebelo/efectos de los fármacos , Femenino , Hipocampo/química , Hipocampo/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Caracteres Sexuales , Xantófilas/farmacologíaRESUMEN
Alzheimer's disease (AD) is the most common form of dementia in the elderly. The vast majority of cases are not linked to a known genetic defect and the molecular mechanisms underlying AD pathogenesis are still elusive. Evidence suggests that mitochondrial dysfunction is a prominent feature of the disease, and that mitochondrial DNA (mtDNA) alterations may represent a possible starting point of the pathophysiological cascade. Although specific mtDNA alterations have been reported in AD patients both in brain and peripheral tissues, such as D-loop mutations, 4977-bp deletion and poly-C tract D310 cytosine insertion, a generalized subtle allelic shift has also been demonstrated. This shift is significant for a few nucleotide positions (nps), but it is also detectable for most nps, although at a lower level. As single allelic substitutions can unlikely be determinant, it is proposed that the combination of all of them could lead to a less efficient oxidative phosphorylation, thus influencing AD development and course.
RESUMEN
Strawberries are an important fruit in the Mediterranean diet because of their high content of essential nutrients and beneficial phytochemicals, which seem to exert beneficial effects in human health. Healthy volunteers were supplemented daily with 500 g of strawberries for 1 month. Plasma lipid profile, circulating and cellular markers of antioxidant status, oxidative stress and platelet function were evaluated at baseline, after 30 days of strawberry consumption and 15 days after the end of the study. A high concentration of vitamin C and anthocyanins was found in the fruits. Strawberry consumption beneficially influenced the lipid profile by significantly reducing total cholesterol, low-density lipoprotein cholesterol and triglycerides levels (-8.78%, -13.72% and -20.80%, respectively; P<.05) compared with baseline period, while high-density lipoprotein cholesterol remained unchanged. Strawberry supplementation also significant decreased serum malondialdehyde, urinary 8-OHdG and isoprostanes levels (-31.40%, -29.67%, -27.90%, respectively; P<.05). All the parameters returned to baseline values after the washout period. A significant increase in plasma total antioxidant capacity measured by both ferric reducing ability of plasma and oxygen radical absorbance capacity assays and vitamin C levels (+24.97%, +41.18%, +41.36%, respectively; P<.05) was observed after strawberry consumption. Moreover, the spontaneous and oxidative hemolysis were significant reduced (-31.7% and -39.03%, respectively; P<.05), compared to the baseline point, which remained stable after the washout period. Finally, strawberry intake significant decrease (P<.05) the number of activated platelets, compared to both baseline and washout values. Strawberries consumption improves plasma lipids profile, biomarkers of antioxidant status, antihemolytic defenses and platelet function in healthy subjects, encouraging further evaluation on a population with higher cardiovascular disease risk.
Asunto(s)
Antocianinas/administración & dosificación , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/metabolismo , Fragaria/química , Estrés Oxidativo , Activación Plaquetaria , Humanos , Factores de RiesgoRESUMEN
To identify biomarkers associated with cognitive stimulation of mild cognitive impairment (MCI) patients, we performed quantitative real-time reverse transcriptase polymerase chain reaction for brain-derived neurotrophic factor (BDNF) mRNA in peripheral lymphocytes of MCI and healthy subjects undergoing a multi-component cognitive training (CT) program. CT determined a significant decrease of BDNF mRNA levels in MCI (fold change=0.31) as compared to healthy subjects (fold change=0.86). It has been reported that in MCI there is an increase of BDNF serum levels, and our findings could indicate a positive effect of CT in restoring pre-disease levels of expression.