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1.
Neurol Sci ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656594

RESUMO

INTRODUCTION: Anti-N-methyl-D-aspartate receptor (NMDAr) antibody encephalitis is an autoimmune disorder characterized by synaptic NMDAr current disruption and receptor hypofunction, often affecting women during pregnancy. Clinical manifestations associated with anti-NMDAr encephalitis can occur both in the mother and fetus. METHODS: We generated a systematic search of the literature to identify epidemiological, clinical, and serological data related to pregnant women with anti-NMDAr encephalitis and their children, analyzing the fetal outcomes. We examined the age and neurologic symptoms of the mothers, the presence of an underlying tumor, immunotherapies used during pregnancy, duration of the pregnancy, and type of delivery. RESULTS: Data from 41 patients were extrapolated from the included studies. Spontaneous interruption of pregnancy, premature birth, and cesarean section were reported in pregnant women with NMDAr encephalitis. Several fetal and neonatal symptoms (e.g., movement disorders, spina bifida, poor sucking, respiratory distress, cardiac arrhythmias, infections, icterus, hypoglycemia, and low birth weight) depending on the mother's serum anti-NR1 concentration were also reported. CONCLUSIONS: We characterized the outcomes of children born from mothers with anti-NMDAr encephalitis, analyzing the pivotal risk factors related to pregnancy and maternal disorder. Neuropsychiatric involvement seems strictly related to pathogenic NMDAr antibodies detected in maternal and/or neonatal serum. These findings clarify a complex condition to manage, outlining the risks associated with pregnant women with anti-NMDAr encephalitis and also providing a concrete guide for therapeutic strategies to prevent potential harm to the fetus and the child's neurodevelopment.

2.
Radiol Med ; 129(5): 712-726, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38538828

RESUMO

Treatment response assessment of rectal cancer patients is a critical component of personalized cancer care and it allows to identify suitable candidates for organ-preserving strategies. This pilot study employed a novel multi-omics approach combining MRI-based radiomic features and untargeted metabolomics to infer treatment response at staging. The metabolic signature highlighted how tumor cell viability is predictively down-regulated, while the response to oxidative stress was up-regulated in responder patients, showing significantly reduced oxoproline values at baseline compared to non-responder patients (p-value < 10-4). Tumors with a high degree of texture homogeneity, as assessed by radiomics, were more likely to achieve a major pathological response (p-value < 10-3). A machine learning classifier was implemented to summarize the multi-omics information and discriminate responders and non-responders. Combining all available radiomic and metabolomic features, the classifier delivered an AUC of 0.864 (± 0.083, p-value < 10-3) with a best-point sensitivity of 90.9% and a specificity of 81.8%. Our results suggest that a multi-omics approach, integrating radiomics and metabolomic data, can enhance the predictive value of standard MRI and could help to avoid unnecessary surgical treatments and their associated long-term complications.


Assuntos
Imageamento por Ressonância Magnética , Metabolômica , Estadiamento de Neoplasias , Neoplasias Retais , Humanos , Projetos Piloto , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Idoso , Resultado do Tratamento , Aprendizado de Máquina , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Adulto , Multiômica
3.
Graefes Arch Clin Exp Ophthalmol ; 262(1): 149-160, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37530849

RESUMO

PURPOSE: To distinguish functioning from failed filtration blebs (FBs) implementing a deep learning (DL) model on slit-lamp images. METHODS: Retrospective, cross-sectional, multicenter study for development and validation of an artificial intelligence classification algorithm. The dataset consisted of 119 post-trabeculectomy FB images of whom we were aware of the surgical outcome. The ground truth labels were annotated and images splitted into three outcome classes: complete (C) or qualified success (Q), and failure (F). Images were prepared implementing various data cleaning and data transformations techniques. A set of DL models were trained using different ResNet architectures as the backbone. Transfer and ensemble learning were then applied to obtain a final combined model. Accuracy, sensitivity, specificity, area under the ROC curve, and area under the precision-recall curve were calculated to evaluate the final model. Kappa coefficient and P value on the accuracy measure were used to prove the statistical significance level. RESULTS: The DL approach reached good results in unraveling FB functionality. Overall, the model accuracy reached a score of 74%, with a sensitivity of 74% and a specificity of 87%. The area under the ROC curve was 0.8, whereas the area under the precision-recall curve was 0.74. The P value was equal to 0.00307, and the Kappa coefficient was 0.58. CONCLUSIONS: All considered metrics supported that the final DL model was able to discriminate functioning from failed FBs, with good accuracy. This approach could support clinicians in the patients' management after glaucoma surgery in absence of adjunctive clinical data.


Assuntos
Aprendizado Profundo , Glaucoma , Trabeculectomia , Humanos , Pressão Intraocular , Estudos Retrospectivos , Inteligência Artificial , Estudos Transversais , Trabeculectomia/métodos , Glaucoma/diagnóstico , Glaucoma/cirurgia
4.
Front Oncol ; 13: 1254674, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692853

RESUMO

Background: Glioblastoma (GBM) is the most common primary brain tumor in adulthood. Initial diagnosis is generally based on clinical and MRI findings, which may be misinterpreted as other neurological pictures, including autoimmune encephalitis (AE). AE is a heterogeneous group of neuroinflammatory diseases due to the presence of auto-antibodies targeting antigens on neuronal synaptic or cell surface. In the present report, we describe two peculiar cases of GBM initially misdiagnosed as AE, focusing on the diagnostic pitfalls and the treatment strategies. Methods: We report the case of two patients with high-grade brain tumors, initially misdiagnosed and treated for AE. Clinical, laboratory, and neuroradiological data are discussed in terms of differential diagnosis between AE and GBM. Results: The presence of atypical brain MRI findings and the unresponsiveness to immunosuppressive treatment are major red flags in the differential diagnosis between AE and GBM. In these cases, a brain biopsy is necessary to confirm the diagnosis. Conclusions: Atypical brain tumor presentation causes a diagnostic and therapeutic delay. A positive onconeural autoantibodies result should always be interpreted cautiously, considering the possibility of a false-positive test. A brain biopsy is mandatory for a definite diagnosis.

5.
Epilepsia Open ; 8(4): 1221-1240, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37562964

RESUMO

Several reports have described the autoimmune encephalitis' (AE) possible onset during pregnancy. In this systematic review, we summarize the available data on the diagnostic and therapeutic approach to AE during pregnancy, highlighting the associated maternal and fetal clinical outcomes. A systematic search of the literature was performed. The following databases were used: PubMed, Google Scholar, EMBASE, and CrossRef. The revision was registered on the PROSPERO platform (CRD42022336357). Forty-nine patients were included. AE onset was mainly observed during the first and the second trimester of pregnancy with psychiatric manifestations and seizures as main onset symptoms. CSF analysis showed AE-specific autoantibody positivity in 33 patients (anti-NMDA receptor as the most frequent). EEG generally showed normal findings. MRI revealed pathological findings in less than half of patients. Tumor screening was positive in 14 cases. First-line immunotherapy (single or combined) was generally employed while second line was administered in a minority of patients. Levetiracetam was the most used antiseizure medication. Cesarean section was performed in 18 women. Most of the women had an excellent early outcome after delivery but 22 showed persistent neurological deficits in long-term follow-up. Fetal outcome was positive in 33 cases, whereas 12 cases of fetal death were reported. A logistic regression showed that no variable significantly influenced the odds of good/bad maternal and fetal clinical outcome. Diagnosis and treatment of AE during pregnancy is challenging. The rate of miscarriage in women with AE seems to be higher than the general population. In addition, mothers may show long-term neurological deficits.


Assuntos
Aborto Espontâneo , Doenças Autoimunes do Sistema Nervoso , Encefalite , Humanos , Gravidez , Feminino , Cesárea , Encefalite/diagnóstico , Encefalite/terapia
6.
J Digit Imaging ; 36(3): 1071-1080, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36698037

RESUMO

Oncotype Dx Recurrence Score (RS) has been validated in patients with ER + /HER2 - invasive breast carcinoma to estimate patient risk of recurrence and guide the use of adjuvant chemotherapy. We investigated the role of MRI-based radiomics features extracted from the tumor and the peritumoral tissues to predict the risk of tumor recurrence. A total of 62 patients with biopsy-proved ER + /HER2 - breast cancer who underwent pre-treatment MRI and Oncotype Dx were included. An RS > 25 was considered discriminant between low-intermediate and high risk of tumor recurrence. Two readers segmented each tumor. Radiomics features were extracted from the tumor and the peritumoral tissues. Partial least square (PLS) regression was used as the multivariate machine learning algorithm. PLS ß-weights of radiomics features included the 5% features with the largest ß-weights in magnitude (top 5%). Leave-one-out nested cross-validation (nCV) was used to achieve hyperparameter optimization and evaluate the generalizable performance of the procedure. The diagnostic performance of the radiomics model was assessed through receiver operating characteristic (ROC) analysis. A null hypothesis probability threshold of 5% was chosen (p < 0.05). The exploratory analysis for the complete dataset revealed an average absolute correlation among features of 0.51. The nCV framework delivered an AUC of 0.76 (p = 1.1∙10-3). When combining "early" and "peak" DCE images of only T or TST, a tendency toward statistical significance was obtained for TST with an AUC of 0.61 (p = 0.05). The 47 features included in the top 5% were balanced between T and TST (23 and 24, respectively). Moreover, 33/47 (70%) were texture-related, and 25/47 (53%) were derived from high-resolution images (1 mm). A radiomics-based machine learning approach shows the potential to accurately predict the recurrence risk in early ER + /HER2 - breast cancer patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Curva ROC , Algoritmos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
7.
J Alzheimers Dis ; 89(2): 405-410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35871352

RESUMO

A 43-year-old came to our observation for progressive cognitive impairment, confirmed by the neuropsychological evaluation. A diagnosis of multidomain amnestic mild cognitive impairment, due to unknown reasons, was posited at the first assessment. The patient's neurological exam was otherwise completely normal. The patient's mother was clinically diagnosed with frontotemporal dementia in her forties. The patient underwent neuroimaging investigations and cerebrospinal fluid analysis. Our diagnostic work-up pointed toward a neurodegenerative etiology, but the presence of concurrent cardiomyopathy emerged in the meantime. Due to the patient's family history, a thorough genetic screening was performed. The results revealed a unique genetic asset, with heterozygotic variants of three amyloid-related genes (PSEN1, APP, and MYBPC3). PSEN1 and MYBPC3 mutations showed distinct pathogenic features and accounted for the patient's brain and cardiac amyloidosis, whereas the APP variant was of uncertain pathological implications.


Assuntos
Doença de Alzheimer , Amiloidose , Disfunção Cognitiva , Demência Frontotemporal , Doença de Alzheimer/patologia , Amiloidose/diagnóstico , Amiloidose/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/genética , Feminino , Demência Frontotemporal/diagnóstico , Humanos , Masculino , Testes Neuropsicológicos
8.
Elife ; 112022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35191835

RESUMO

The membrane protein TREM2 (Triggering Receptor Expressed on Myeloid cells 2) regulates key microglial functions including phagocytosis and chemotaxis. Loss-of-function variants of TREM2 are associated with increased risk of Alzheimer's disease (AD). Because abnormalities in Ca2+ signaling have been observed in several AD models, we investigated TREM2 regulation of Ca2+ signaling in human induced pluripotent stem cell-derived microglia (iPSC-microglia) with genetic deletion of TREM2. We found that iPSC-microglia lacking TREM2 (TREM2 KO) show exaggerated Ca2+ signals in response to purinergic agonists, such as ADP, that shape microglial injury responses. This ADP hypersensitivity, driven by increased expression of P2Y12 and P2Y13 receptors, results in greater release of Ca2+ from the endoplasmic reticulum stores, which triggers sustained Ca2+ influx through Orai channels and alters cell motility in TREM2 KO microglia. Using iPSC-microglia expressing the genetically encoded Ca2+ probe, Salsa6f, we found that cytosolic Ca2+ tunes motility to a greater extent in TREM2 KO microglia. Despite showing greater overall displacement, TREM2 KO microglia exhibit reduced directional chemotaxis along ADP gradients. Accordingly, the chemotactic defect in TREM2 KO microglia was rescued by reducing cytosolic Ca2+ using a P2Y12 receptor antagonist. Our results show that loss of TREM2 confers a defect in microglial Ca2+ response to purinergic signals, suggesting a window of Ca2+ signaling for optimal microglial motility.


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , Difosfato de Adenosina/metabolismo , Doença de Alzheimer/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Microglia/metabolismo , Receptores Imunológicos/metabolismo , Receptores Purinérgicos/metabolismo
9.
Biomolecules ; 11(7)2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209820

RESUMO

Evidence indicates that patients with Alzheimer's dementia (AD) show signs of copper (Cu) dyshomeostasis. This study aimed at evaluating the potential of Cu dysregulation as an AD susceptibility factor. We performed a meta-analysis of 56 studies investigating Cu biomarkers in brain specimens (pooled total of 182 AD and 166 healthy controls, HC) and in serum/plasma (pooled total of 2929 AD and 3547 HC). We also completed a replication study of serum Cu biomarkers in 97 AD patients and 70 HC screened for rs732774 and rs1061472 ATP7B, the gene encoding for the Cu transporter ATPase7B. Our meta-analysis showed decreased Cu in AD brain specimens, increased Cu and nonbound ceruloplasmin (Non-Cp) Cu in serum/plasma samples, and unchanged ceruloplasmin. Serum/plasma Cu excess was associated with a three to fourfold increase in the risk of having AD. Our replication study confirmed meta-analysis results and showed that carriers of the ATP7B AG haplotype were significantly more frequent in the AD group. Overall, our study shows that AD patients fail to maintain a Cu metabolic balance and reveals the presence of a percentage of AD patients carrying ATP7B AG haplotype and presenting Non-Cp Cu excess, which suggest that a subset of AD subjects is prone to Cu imbalance. This AD subtype can be the target of precision medicine-based strategies tackling Cu dysregulation.


Assuntos
Doença de Alzheimer/metabolismo , ATPases Transportadoras de Cobre/genética , Cobre/metabolismo , Adenosina Trifosfatases/genética , Doença de Alzheimer/genética , Biomarcadores/análise , Encéfalo/metabolismo , Proteínas de Transporte de Cátions/genética , Ceruloplasmina/análise , Cobre/sangue , Suscetibilidade a Doenças , Haplótipos/genética , Homeostase , Humanos , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
10.
Front Neurol ; 12: 806839, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35087476

RESUMO

Purpose: Brain tumor-related epilepsy (BTRE) is a condition characterized by the development of seizures in the context of an undergoing oncological background. Levetiracetam (LEV) is a third-generation anti-seizure medication (ASM) widely used in BTRE prophylaxis. The study evaluated LEV neuropsychiatric side effects (SEs) in BTRE prophylaxis. Method: Twenty-eight patients with brain tumors were retrospectively selected and divided into two groups. In one group, we evaluated patients with a BTRE diagnosis using LEV (BTRE-group). The other group included patients with brain tumors who never had epilepsy and used a prophylactic ASM regimen with LEV (PROPHYLAXIS-group). Neuropsychiatric SEs of LEV were monitored using the Neuropsychiatric Inventory Questionnaire (NPI-Q) at the baseline visit and the 6- and 12-month follow-up. Results: Eighteen patients of the BTRE-group and 10 patients of the PROPHYLAXIS-group were included. Compared to the BTRE-group, the PROPHYLAXIS-group showed a higher severity of neuropsychiatric symptoms. According to Linear Mixed Models (LMM), a multiplicative effect was observed for the interaction between group treatment and time. For the caregiver distress score (CDS), only a time-effect was observed. Conclusion: Prophylactic ASM with LEV is associated with an increased frequency of neuropsychiatric SE. Accurate epileptological evaluations in patients with brain tumors are mandatory to select who would benefit most from ASM.

11.
Case Rep Neurol ; 12(3): 307-313, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082769

RESUMO

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a rare inflammatory disorder featured by pontocerebellar dysfunctions and, in some cases, later cognitive disturbances. Here, we describe an atypical presentation of CLIPPERS, characterized by clinical onset with neuropsychiatric and cognitive symptoms. A 45-year-old man was referred to our Memory Clinic due to difficulties at work for over a month, caused by confusion and asthenia. Furthermore, insomnia and mood changes appeared. These disturbances were unresponsive to antipsychotic and antidepressant drugs. At admission, the patient presented also with severe cognitive impairment, urinary incontinence, ataxic gait, and limitation of lateral conjugate gaze. During the hospitalization, the patient underwent cerebrospinal fluid analysis, serum systemic autoimmune disorders laboratory research, neoplastic markers analysis, and brain MRI scan. The radiological and laboratory findings were compatible with the diagnosis of CLIPPERS. The sudden clinical and radiological improvement of the patient's conditions, after only a week of steroid therapy, further confirmed our clinical suspicion. The present case enhances the necessity to consider CLIPPERS in the differential diagnosis of pre-senile cognitive impairment, even in the absence of early pontocerebellar neurological signs. Before the spreading of the neuroinflammatory and degenerative processes, CLIPPERS represents one among the few possible reversible causes of cognitive decline.

12.
Aging (Albany NY) ; 11(1): 73-88, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30620722

RESUMO

Circulating ceramide levels are abnormally elevated in age-dependent pathologies such as cardiovascular diseases, obesity and Alzheimer's disease. Nevertheless, the potential impact of age on plasma ceramide levels has not yet been systematically examined. In the present study, we quantified a focused panel of plasma ceramides and dihydroceramides in a cohort of 164 subjects (84 women) 19 to 80 years of age. After adjusting for potential confounders, multivariable linear regression analysis revealed a positive association between age and ceramide (d18:1/24:0) (ß (SE) = 5.67 (2.38); p = .0198) and ceramide (d18:1/24:1) (ß (SE) = 2.88 (.61); p < .0001) in women, and between age and ceramide (d18:1/24:1) in men (ß (SE) = 1.86 (.77); p = .0179). In women of all ages, but not men, plasma ceramide (d18:1/24:1) was negatively correlated with plasma estradiol (r = -0.294; p = .007). Finally, in vitro experiments in human cancer cells expressing estrogen receptors showed that incubation with estradiol (10 nM, 24 h) significantly decreased ceramide accumulation. Together, the results suggest that aging is associated with an increase in circulating ceramide levels, which in post-menopausal women is at least partially associated with lower estradiol levels.


Assuntos
Envelhecimento/sangue , Ceramidas/sangue , Adulto , Idoso , Envelhecimento/fisiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pós-Menopausa , Adulto Jovem
13.
Neurobiol Aging ; 64: 33-43, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29331730

RESUMO

Modulation of insulin-dependent signaling is emerging as a valuable therapeutic tool to target neurodegeneration. In the brain, the activation of insulin receptors promotes cell growth, neuronal repair, and protection. Altered brain insulin signaling participates in the cognitive decline seen in Alzheimer's disease patients and the aging brain. Glucagon-like peptide-1 (GLP-1) regulates insulin secretion and, along with GLP-1 analogues, enhances neurotrophic signaling and counteracts cognitive deficits in preclinical models of neurodegeneration. Moreover, recent evidence indicates that GLP-1 modulates the activity of the brain-derived neurotrophic factor (BDNF). In this study, in adult wild-type mice, here employed as a model of mid-life brain aging, we evaluated the effects of a 2-month treatment with exenatide, a GLP-1 analogue. We found that exenatide promotes the enhancement of long-term memory performances. Biochemical and imaging analyses show that the drug promotes the activation of the BDNF-TrkB neurotrophic axis and inhibits apoptosis by decreasing p75NTR-mediated signaling. The study provides preclinical evidence for the use of exenatide to delay age-dependent cognitive decline.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cognição/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Glicoproteínas de Membrana/metabolismo , Memória de Longo Prazo/efeitos dos fármacos , Nootrópicos , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Proteínas Tirosina Quinases/metabolismo , Peçonhas/farmacologia , Peçonhas/uso terapêutico , Animais , Encéfalo/metabolismo , Células Cultivadas , Envelhecimento Cognitivo , Disfunção Cognitiva/etiologia , Exenatida , Feminino , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Insulina/fisiologia , Masculino , Camundongos Endogâmicos , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
14.
PLoS One ; 7(10): e46649, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23056385

RESUMO

Mitochondria mediate dual metabolic and Ca(2+) shuttling activities. While the former is required for Ca(2+) signalling linked to insulin secretion, the role of the latter in ß cell function has not been well understood, primarily because the molecular identity of the mitochondrial Ca(2+) transporters were elusive and the selectivity of their inhibitors was questionable. This study focuses on NCLX, the recently discovered mitochondrial Na(+)/Ca(2+) exchanger that is linked to Ca(2+) signalling in MIN6 and primary ß cells. Suppression either of NCLX expression, using a siRNA construct (siNCLX) or of its activity, by a dominant negative construct (dnNCLX), enhanced mitochondrial Ca(2+) influx and blocked efflux induced by glucose or by cell depolarization. In addition, NCLX regulated basal, but not glucose-dependent changes, in metabolic rate, mitochondrial membrane potential and mitochondrial resting Ca(2+). Importantly, NCLX controlled the rate and amplitude of cytosolic Ca(2+) changes induced by depolarization or high glucose, indicating that NCLX is a critical and rate limiting component in the cross talk between mitochondrial and plasma membrane Ca(2+) signalling. Finally, knockdown of NCLX expression was followed by a delay in glucose-dependent insulin secretion. These findings suggest that the mitochondrial Na(+)/Ca(2+) exchanger, NCLX, shapes glucose-dependent mitochondrial and cytosolic Ca(2+) signals thereby regulating the temporal pattern of insulin secretion in ß cells.


Assuntos
Sinalização do Cálcio/fisiologia , Glucose/metabolismo , Insulina/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Sinalização do Cálcio/genética , Células Cultivadas , Feminino , Células Secretoras de Insulina/metabolismo , Camundongos , Mitocôndrias , Transdução de Sinais/fisiologia , Trocador de Sódio e Cálcio/genética
15.
PLoS One ; 6(1): e15965, 2011 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-21298039

RESUMO

BACKGROUND: A typical pathological feature of Alzheimer's disease (AD) is the appearance in the brain of senile plaques made up of ß-amyloid (Aß) and neurofibrillary tangles. AD is also associated with an abnormal accumulation of some metal ions, and we have recently shown that one of these, aluminum (Al), plays a relevant role in affecting Aß aggregation and neurotoxicity. METHODOLOGY: In this study, employing a microarray analysis of 35,129 genes, we investigated the effects induced by the exposure to the Aß(1-42)-Al (Aß-Al) complex on the gene expression profile of the neuronal-like cell line, SH-SY5Y. PRINCIPAL FINDINGS: The microarray assay indicated that, compared to Aß or Al alone, exposure to Aß-Al complex produced selective changes in gene expression. Some of the genes selectively over or underexpressed are directly related to AD. A further evaluation performed with Ingenuity Pathway analysis revealed that these genes are nodes of networks and pathways that are involved in the modulation of Ca(2+) homeostasis as well as in the regulation of glutamatergic transmission and synaptic plasticity. CONCLUSIONS AND SIGNIFICANCE: Aß-Al appears to be largely involved in the molecular machinery that regulates neuronal as well as synaptic dysfunction and loss. Aß-Al seems critical in modulating key AD-related pathways such as glutamatergic transmission, Ca(2+) homeostasis, oxidative stress, inflammation, and neuronal apoptosis.


Assuntos
Alumínio/farmacologia , Peptídeos beta-Amiloides/farmacologia , Neuroblastoma/genética , Neuroblastoma/patologia , Fragmentos de Peptídeos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Cálcio/metabolismo , Perfilação da Expressão Gênica , Ácido Glutâmico , Humanos , Inflamação/genética , Análise em Microsséries , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/genética
16.
Rejuvenation Res ; 11(5): 861-71, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18788899

RESUMO

Recent findings suggest that beta-amyloid (A beta) is more neurotoxic when present in its oligomeric configuration rather than as monomers or fibrils. Previous work from our laboratories has shown that A beta aggregation is strongly influenced by the conjugation of the peptide with metal ions (aluminum A, copper [Cu], zinc [Zn], and iron [Fe]) that are found in high concentrations in the core of senile plaques. Disruption of Ca++ signaling and mitochondrial dysfunction are potent triggers of neuronal death and have been implicated in the neuronal loss that is associated with Alzheimer's disease (AD). In this study, we explored whether A beta-metal complexes can have detrimental effects on intraneuronal Ca++ ([Ca++]i) homeostasis and mitochondrial function in vitro. Results from our experiments indicate that, when conjugated with Al, A beta perturbs neuronal [Ca++]i homeostasis and inhibits mitochondrial respiration. Finally, we analyzed the content of the four metals in the brain of a triple transgenic animal model of AD and found that Al is the only one to be increased in the cortex of these mice.


Assuntos
Alumínio/toxicidade , Doença de Alzheimer/etiologia , Peptídeos beta-Amiloides/toxicidade , Sinalização do Cálcio/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Alumínio/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/genética , Animais , Modelos Animais de Doenças , Homeostase/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Fluidez de Membrana/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Complexos Multiproteicos , N-Metilaspartato/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Ratos , Ratos Wistar
17.
Brain Res ; 1168: 90-6, 2007 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-17706944

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder which is mostly sporadic, although about 5-10% of the cases are inherited. About 15-20% of patients with familial ALS (FALS) carry mutations in the gene encoding the free radical scavenging enzyme Cu/Zn superoxide dismutase (SOD1). In this study, we explored the potential neuroprotective effects of antioxidant strategies based on either a tomato-enriched diet, or pyruvate administration, in an animal model of ALS. To that aim, transgenic mice expressing a mutant form of SOD1 [the gly(93) --> ala (G93A) substitution; G93A SOD1] were fed on either tomato-enriched food pellets or the Altromin diet in which milk serum and proteins substitute for soy and fish flours. In both cases, treatments were started at the 29th day of age. In a second set of experiments, G93A SOD1 mice were treated with pyruvate intraperitoneally (500 mg/kg, i.p; starting at the 70th day of age) and compared with control mice receiving i.p. saline injections. Our results indicate that neither the tomato-enriched diet nor pyruvate administration caused any significant effect on the overall survival time and disease onset in G93A SOD1 mice. Thus, despite the wealth of data indicating the relevant role of oxidative stress and defective energy homeostasis both in patients and animal models of ALS, antioxidant strategies based on tomato-enriched food or pyruvate seem to be not sufficient to promote a disease modifying effect in an animal model of ALS.


Assuntos
Idade de Início , Esclerose Lateral Amiotrófica/terapia , Antioxidantes/uso terapêutico , Alimentos Fortificados , Ácido Pirúvico/uso terapêutico , Solanum lycopersicum , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/mortalidade , Animais , Carotenoides/sangue , Modelos Animais de Doenças , Flavonoides/sangue , Humanos , Camundongos , Camundongos Transgênicos , Superóxido Dismutase/genética , Análise de Sobrevida
18.
Hum Mol Genet ; 16(1): 61-77, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17135277

RESUMO

A truncated form of the Huntington's disease (HD) protein that contains the polyglutamine repeat, Httex1p, causes HD-like phenotypes in multiple model organisms. Molecular signatures of pathogenesis appear to involve distinct domains within this polypeptide. We studied the contribution of each domain, singly or in combination, to sub-cellular localization, aggregation and intracellular Ca2+ ([Ca2+]i) dynamics in cells. We demonstrate that sub-cellular localization is most strongly influenced by the first 17 amino acids, with this sequence critically controlling Httex1p mitochondrial localization and also promoting association with the endoplasmic reticulum (ER) and Golgi. This domain also enhances the formation of visible aggregates and together with the expanded polyQ repeat acutely disrupts [Ca2+]i levels in glutamate-challenged PC12 cells. Isolated cortical mitochondria incubated with Httex1p resulted in uncoupling and depolarization of these organelles, further supporting the idea that Httex1p-dependent mitochondrial dysfunction could be instrumental in promoting acute Ca2+ dyshomeostasis. Interestingly, neither mitochondrial nor ER associations seem to be required to promote long-term [Ca2+]i dyshomeostasis.


Assuntos
Cálcio/metabolismo , Citoplasma/metabolismo , Proteínas do Tecido Nervoso/química , Proteínas Nucleares/química , Animais , Membrana Celular/metabolismo , Córtex Cerebelar/metabolismo , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Homeostase , Proteína Huntingtina , Masculino , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/fisiologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/fisiologia , Células PC12 , Peptídeos/genética , Prolina/química , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transfecção
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