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1.
Am J Hum Genet ; 107(4): 753-762, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32910914

RESUMO

Lamin B1 plays an important role in the nuclear envelope stability, the regulation of gene expression, and neural development. Duplication of LMNB1, or missense mutations increasing LMNB1 expression, are associated with autosomal-dominant leukodystrophy. On the basis of its role in neurogenesis, it has been postulated that LMNB1 variants could cause microcephaly. Here, we confirm this hypothesis with the identification of de novo mutations in LMNB1 in seven individuals with pronounced primary microcephaly (ranging from -3.6 to -12 SD) associated with relative short stature and variable degree of intellectual disability and neurological features as the core symptoms. Simplified gyral pattern of the cortex and abnormal corpus callosum were noted on MRI of three individuals, and these individuals also presented with a more severe phenotype. Functional analysis of the three missense mutations showed impaired formation of the LMNB1 nuclear lamina. The two variants located within the head group of LMNB1 result in a decrease in the nuclear localization of the protein and an increase in misshapen nuclei. We further demonstrate that another mutation, located in the coil region, leads to increased frequency of condensed nuclei and lower steady-state levels of lamin B1 in proband lymphoblasts. Our findings collectively indicate that de novo mutations in LMNB1 result in a dominant and damaging effect on nuclear envelope formation that correlates with microcephaly in humans. This adds LMNB1 to the growing list of genes implicated in severe autosomal-dominant microcephaly and broadens the phenotypic spectrum of the laminopathies.


Assuntos
Nanismo/genética , Deficiência Intelectual/genética , Lamina Tipo B/genética , Microcefalia/genética , Mutação , Lâmina Nuclear/genética , Sequência de Aminoácidos , Sequência de Bases , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Pré-Escolar , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/metabolismo , Corpo Caloso/patologia , Nanismo/diagnóstico por imagem , Nanismo/metabolismo , Nanismo/patologia , Feminino , Expressão Gênica , Humanos , Lactente , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/metabolismo , Deficiência Intelectual/patologia , Lamina Tipo B/metabolismo , Linfócitos/metabolismo , Linfócitos/patologia , Imageamento por Ressonância Magnética , Masculino , Microcefalia/diagnóstico por imagem , Microcefalia/metabolismo , Microcefalia/patologia , Lâmina Nuclear/metabolismo , Lâmina Nuclear/patologia
2.
J Med Genet ; 57(4): 269-273, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31494577

RESUMO

INTRODUCTION: Lynch syndrome (LS) and constitutional mismatch repair deficiency (CMMRD) are hereditary cancer syndromes associated with mismatch repair (MMR) deficiency. Tumours show microsatellite instability (MSI), also reported at low levels in non-neoplastic tissues. Our aim was to evaluate the performance of high-sensitivity MSI (hs-MSI) assessment for the identification of LS and CMMRD in non-neoplastic tissues. MATERIALS AND METHODS: Blood DNA samples from 131 individuals were grouped into three cohorts: baseline (22 controls), training (11 CMMRD, 48 LS and 15 controls) and validation (18 CMMRD and 18 controls). Custom next generation sequencing panel and bioinformatics pipeline were used to detect insertions and deletions in microsatellite markers. An hs-MSI score was calculated representing the percentage of unstable markers. RESULTS: The hs-MSI score was significantly higher in CMMRD blood samples when compared with controls in the training cohort (p<0.001). This finding was confirmed in the validation set, reaching 100% specificity and sensitivity. Higher hs-MSI scores were detected in biallelic MSH2 carriers (n=5) compared with MSH6 carriers (n=15). The hs-MSI analysis did not detect a difference between LS and control blood samples (p=0.564). CONCLUSIONS: The hs-MSI approach is a valuable tool for CMMRD diagnosis, especially in suspected patients harbouring MMR variants of unknown significance or non-detected biallelic germline mutations.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Instabilidade de Microssatélites , Proteína 2 Homóloga a MutS/genética , Síndromes Neoplásicas Hereditárias/genética , Adolescente , Adulto , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Neoplasias Colorretais Hereditárias sem Polipose/sangue , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Reparo de Erro de Pareamento de DNA/genética , Feminino , Mutação em Linhagem Germinativa/genética , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Masculino , Síndromes Neoplásicas Hereditárias/sangue , Síndromes Neoplásicas Hereditárias/patologia , Adulto Jovem
3.
Int J Mol Sci ; 22(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34445555

RESUMO

Previous evidence links the formation of extranuclear inclusions of transcription factors, such as ERK, Jun, TDP-43, and REST, with oxidative, endoplasmic-reticulum, proteasomal, and osmotic stress. To further characterize its extranuclear location, we performed a high-content screening based on confocal microscopy and automatized image analyses of an epithelial cell culture treated with hydrogen peroxide, thapsigargin, epoxomicin, or sorbitol at different concentrations and times to recreate the stresses mentioned above. We also performed a subcellular fractionation of the brain from transgenic mice overexpressing the Q331K-mutated TARDBP, and we analyzed the REST-regulated mRNAs. The results show that these nuclear proteins exhibit a mitochondrial location, together with significant nuclear/extranuclear ratio changes, in a protein and stress-specific manner. The presence of these proteins in enriched mitochondrial fractions in vivo confirmed the results of the image analyses. TDP-43 aggregation was associated with alterations in the mRNA levels of the REST target genes involved in calcium homeostasis, apoptosis, and metabolism. In conclusion, cell stress increased the mitochondrial translocation of nuclear proteins, increasing the chance of proteostasis alterations. Furthermore, TDP-43 aggregation impacts REST target genes, disclosing an exciting interaction between these two transcription factors in neurodegenerative processes.


Assuntos
Encéfalo/patologia , Estresse do Retículo Endoplasmático , Glândulas Mamárias Humanas/patologia , Mitocôndrias/patologia , Estresse Oxidativo , Fatores de Transcrição/metabolismo , Animais , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Glândulas Mamárias Humanas/metabolismo , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo
4.
J Bacteriol ; 202(22)2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900827

RESUMO

Phenotypic testing for drug susceptibility of Mycobacterium tuberculosis is critical to basic research and managing the evolving problem of antimicrobial resistance in tuberculosis management, but it remains a specialized technique to which access is severely limited. Here, we report on the development and validation of an improved phage-mediated detection system for M. tuberculosis We incorporated a nanoluciferase (Nluc) reporter gene cassette into the TM4 mycobacteriophage genome to create phage TM4-nluc. We assessed the performance of this reporter phage in the context of cellular limit of detection and drug susceptibility testing using multiple biosafety level 2 drug-sensitive and -resistant auxotrophs as well as virulent M. tuberculosis strains. For both limit of detection and drug susceptibility testing, we developed a standardized method consisting of a 96-hour cell preculture followed by a 72-hour experimental window for M. tuberculosis detection with or without antibiotic exposure. The cellular limit of detection of M. tuberculosis in a 96-well plate batch culture was ≤102 CFU. Consistent with other phenotypic methods for drug susceptibility testing, we found TM4-nluc to be compatible with antibiotics representing multiple classes and mechanisms of action, including inhibition of core central dogma functions, cell wall homeostasis, metabolic inhibitors, compounds currently in clinical trials (SQ109 and Q203), and susceptibility testing for bedaquiline, pretomanid, and linezolid (components of the BPaL regimen for the treatment of multi- and extensively drug-resistant tuberculosis). Using the same method, we accurately identified rifampin-resistant and multidrug-resistant M. tuberculosis strains.IMPORTANCEMycobacterium tuberculosis, the causative agent of tuberculosis disease, remains a public health crisis on a global scale, and development of new interventions and identification of drug resistance are pillars in the World Health Organization End TB Strategy. Leveraging the tractability of the TM4 mycobacteriophage and the sensitivity of the nanoluciferase reporter enzyme, the present work describes an evolution of phage-mediated detection and drug susceptibility testing of M. tuberculosis, adding a valuable tool in drug discovery and basic biology research. With additional validation, this system may play a role as a quantitative phenotypic reference method and complement to genotypic methods for diagnosis and antibiotic susceptibility testing.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana/métodos , Micobacteriófagos/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/farmacologia , Humanos , Luciferases/genética , Luciferases/metabolismo , Medições Luminescentes , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/virologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Pulmonar/microbiologia
5.
Br J Cancer ; 119(8): 978-987, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30283143

RESUMO

BACKGROUND: Constitutional MLH1 epimutations are characterised by monoallelic methylation of the MLH1 promoter throughout normal tissues, accompanied by allele-specific silencing. The mechanism underlying primary MLH1 epimutations is currently unknown. The aim of this study was to perform an in-depth characterisation of constitutional MLH1 epimutations targeting the aberrantly methylated region around MLH1 and other genomic loci. METHODS: Twelve MLH1 epimutation carriers, 61 Lynch syndrome patients, and 41 healthy controls, were analysed by Infinium 450 K array. Targeted molecular techniques were used to characterise the MLH1 epimutation carriers and their inheritance pattern. RESULTS: No nucleotide or structural variants were identified in-cis on the epimutated allele in 10 carriers, in which inter-generational methylation erasure was demonstrated in two, suggesting primary type of epimutation. CNVs outside the MLH1 locus were found in two cases. EPM2AIP1-MLH1 CpG island was identified as the sole differentially methylated region in MLH1 epimutation carriers compared to controls. CONCLUSION: Primary constitutional MLH1 epimutations arise as a focal epigenetic event at the EPM2AIP1-MLH1 CpG island in the absence of cis-acting genetic variants. Further molecular characterisation is needed to elucidate the mechanistic basis of MLH1 epimutations and their heritability/reversibility.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais/genética , Metilação de DNA/genética , Epigênese Genética/genética , Predisposição Genética para Doença/genética , Proteína 1 Homóloga a MutL/genética , Sequência de Bases , Neoplasias Colorretais/epidemiologia , Ilhas de CpG/genética , Feminino , Haplótipos/genética , Humanos , Masculino , Mutação/genética , Regiões Promotoras Genéticas/genética , Análise de Sequência de DNA
6.
BMC Med ; 16(1): 28, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29471877

RESUMO

BACKGROUND: Depression is viewed as a major and increasing public health issue, as it causes high distress in the people experiencing it and considerable financial costs to society. Efforts are being made to reduce this burden by preventing depression. A critical component of this strategy is the ability to assess the individual level and profile of risk for the development of major depression. This paper presents the cost-effectiveness of a personalized intervention based on the risk of developing depression carried out in primary care, compared with usual care. METHODS: Cost-effectiveness analyses are nested within a multicentre, clustered, randomized controlled trial of a personalized intervention to prevent depression. The study was carried out in 70 primary care centres from seven cities in Spain. Two general practitioners (GPs) were randomly sampled from those prepared to participate in each centre (i.e. 140 GPs), and 3326 participants consented and were eligible to participate. The intervention included the GP communicating to the patient his/her individual risk for depression and personal risk factors and the construction by both GPs and patients of a psychosocial programme tailored to prevent depression. In addition, GPs carried out measures to activate and empower the patients, who also received a leaflet about preventing depression. GPs were trained in a 10- to 15-h workshop. Costs were measured from a societal and National Health care perspective. Qualityadjustedlife years were assessed using the EuroQOL five dimensions questionnaire. The time horizon was 18 months. RESULTS: With a willingness-to-pay threshold of €10,000 (£8568) the probability of cost-effectiveness oscillated from 83% (societal perspective) to 89% (health perspective). If the threshold was increased to €30,000 (£25,704), the probability of being considered cost-effective was 94% (societal perspective) and 96%, respectively (health perspective). The sensitivity analysis confirmed these results. CONCLUSIONS: Compared with usual care, an intervention based on personal predictors of risk of depression implemented by GPs is a cost-effective strategy to prevent depression. This type of personalized intervention in primary care should be further developed and evaluated. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01151982. Registered on June 29, 2010.


Assuntos
Depressão/prevenção & controle , Atenção Primária à Saúde/economia , Atenção Primária à Saúde/métodos , Análise por Conglomerados , Análise Custo-Benefício , Depressão/economia , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Medição de Risco
7.
Int J Cancer ; 141(7): 1365-1380, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28577310

RESUMO

In a proportion of patients presenting mismatch repair (MMR)-deficient tumors, no germline MMR mutations are identified, the so-called Lynch-like syndrome (LLS). Recently, MMR-deficient tumors have been associated with germline mutations in POLE and MUTYH or double somatic MMR events. Our aim was to elucidate the molecular basis of MSH2-deficient LS-suspected cases using a comprehensive analysis of colorectal cancer (CRC)-associated genes at germline and somatic level. Fifty-eight probands harboring MSH2-deficient tumors were included. Germline mutational analysis of MSH2 (including EPCAM deletions) and MSH6 was performed. Pathogenicity of MSH2 variants was assessed by RNA analysis and multifactorial likelihood calculations. MSH2 cDNA and methylation of MSH2 and MSH6 promoters were studied. Matched blood and tumor DNA were analyzed using a customized next generation sequencing panel. Thirty-five individuals were carriers of pathogenic or probably pathogenic variants in MSH2 and EPCAM. Five patients harbored 4 different MSH2 variants of unknown significance (VUS) and one had 2 novel MSH6 promoter VUS. Pathogenicity assessment allowed the reclassification of the 4 MSH2 VUS and 6 probably pathogenic variants as pathogenic mutations, enabling a total of 40 LS diagnostics. Predicted pathogenic germline variants in BUB1, SETD2, FAN1 and MUTYH were identified in 5 cases. Three patients had double somatic hits in MSH2 or MSH6, and another 2 had somatic alterations in other MMR genes and/or proofreading polymerases. In conclusion, our comprehensive strategy combining germline and somatic mutational status of CRC-associated genes by means of a subexome panel allows the elucidation of up to 86% of MSH2-deficient suspected LS tumors.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Proteínas de Ligação a DNA/genética , Mutação em Linhagem Germinativa , Proteína 2 Homóloga a MutS/deficiência , Proteína 2 Homóloga a MutS/genética , DNA Glicosilases/genética , Metilação de DNA , Análise Mutacional de DNA , Proteínas de Ligação a DNA/deficiência , Endodesoxirribonucleases , Molécula de Adesão da Célula Epitelial/genética , Exodesoxirribonucleases/genética , Sequenciamento de Nucleotídeos em Larga Escala , Histona-Lisina N-Metiltransferase/genética , Humanos , Perda de Heterozigosidade , Enzimas Multifuncionais , Regiões Promotoras Genéticas/genética , Proteínas Serina-Treonina Quinases/genética
8.
Ann Intern Med ; 164(10): 656-65, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27019334

RESUMO

BACKGROUND: Not enough is known about universal prevention of depression in adults. OBJECTIVE: To evaluate the effectiveness of an intervention to prevent major depression. DESIGN: Multicenter, cluster randomized trial with sites randomly assigned to usual care or an intervention. (ClinicalTrials.gov: NCT01151982). SETTING: 10 primary care centers in each of 7 cities in Spain. PARTICIPANTS: Two primary care physicians (PCPs) and 5236 nondepressed adult patients were randomly sampled from each center; 3326 patients consented and were eligible to participate. INTERVENTION: For each patient, PCPs communicated individual risk for depression and personal predictors of risk and developed a psychosocial program tailored to prevent depression. MEASUREMENTS: New cases of major depression, assessed every 6 months for 18 months. RESULTS: At 18 months, 7.39% of patients in the intervention group (95% CI, 5.85% to 8.95%) developed major depression compared with 9.40% in the control (usual care) group (CI, 7.89% to 10.92%) (absolute difference, -2.01 percentage points [CI, -4.18 to 0.16 percentage points]; P = 0.070). Depression incidence was lower in the intervention centers in 5 cities and similar between intervention and control centers in 2 cities. LIMITATION: Potential self-selection bias due to nonconsenting patients. CONCLUSION: Compared with usual care, an intervention based on personal predictors of risk for depression implemented by PCPs provided a modest but nonsignificant reduction in the incidence of major depression. Additional study of this approach may be warranted. PRIMARY FUNDING SOURCE: Institute of Health Carlos III.


Assuntos
Transtorno Depressivo Maior/prevenção & controle , Atenção Primária à Saúde/métodos , Transtorno Depressivo Maior/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Espanha/epidemiologia
9.
Int J Legal Med ; 130(2): 415-20, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26872470

RESUMO

Sudden infant death syndrome is the unexpected demise of a child younger than 1 year of age which remains unexplained after a complete autopsy investigation. Usually, it occurs during sleep, in males, and during the first 12 weeks of life. The pathophysiological mechanism underlying the death is unknown, and the lethal episode is considered multifactorial. However, in cases without a conclusive post-mortem diagnosis, suspicious of cardiac arrhythmias may also be considered as a cause of death, especially in families suffering from any cardiac disease associated with sudden cardiac death. Here, we review current understanding of sudden infant death, focusing on genetic causes leading to lethal cardiac arrhythmias, considering both genes encoding ion channels as well as structural proteins due to recent association of channelopathies and desmosomal genes. We support a comprehensive analysis of all genes associated with sudden cardiac death in families suffering of infant death. It allows the identification of the most plausible cause of death but also of family members at risk, providing cardiologists with essential data to adopt therapeutic preventive measures in families affected with this lethal entity.


Assuntos
Arritmias Cardíacas/genética , Canalopatias/genética , Morte Súbita do Lactente/genética , Variação Genética , Humanos , Lactente , Mutação , Morte Súbita do Lactente/epidemiologia
10.
J Pineal Res ; 61(3): 396-407, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27484637

RESUMO

Effects of sorafenib in hepatocellular carcinoma (HCC) are frequently transient due to tumor-acquired resistance, a phenotype that could be targeted by other molecules to reduce this adaptive response. Because melatonin is known to exert antitumor effects in HCC cells, this study investigated whether and how melatonin reduces resistance to sorafenib. Susceptibility to sorafenib (10 nmol/L to 50 µmol/L) in the presence of melatonin (1 and 2 mmol/L) was assessed in HCC cell lines HepG2, HuH7, and Hep3B. Cell viability was reduced by sorafenib from 1 µmol/L in HepG2 or HuH7 cells, and 2.5 µmol/L in Hep3B cells. Co-administration of melatonin and sorafenib exhibited a synergistic cytotoxic effect on HepG2 and HuH7 cells, while Hep3B cells displayed susceptibility to doses of sorafenib that had no effect when administrated alone. Co-administration of 2.5 µmol/L sorafenib and 1 mmol/L melatonin induced apoptosis in Hep3B cells, increasing PARP hydrolysis and BAX expression. We also observed an early colocalization of mitochondria with lysosomes, correlating with the expression of mitophagy markers PINK1 and Parkin and a reduction of mitofusin-2 and mtDNA compared with sorafenib administration alone. Moreover, increased reactive oxygen species production and mitochondrial membrane depolarization were elicited by drug combination, suggesting their contribution to mitophagy induction. Interestingly, Parkin silencing by siRNA to impair mitophagy significantly reduced cell killing, PARP cleavage, and BAX expression. These results demonstrate that the pro-oxidant capacity of melatonin and its impact on mitochondria stability and turnover via mitophagy increase sensitivity to the cytotoxic effect of sorafenib.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Melatonina/farmacologia , Mitofagia/efeitos dos fármacos , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas de Neoplasias/metabolismo , Niacinamida/farmacologia , Sorafenibe
11.
Hum Mol Genet ; 22(17): 3460-76, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23648430

RESUMO

Current evidence indicates that excess brain cholesterol regulates amyloid-ß (Aß) deposition, which in turn can regulate cholesterol homeostasis. Moreover, Aß neurotoxicity is potentiated, in part, by mitochondrial glutathione (mGSH) depletion. To better understand the relationship between alterations in cholesterol homeostasis and Alzheimer's disease (AD), we generated a triple transgenic mice featuring sterol regulatory element-binding protein-2 (SREBP-2) overexpression in combination with APPswe/PS1ΔE9 mutations (APP/PS1) to examine key biochemical and functional characteristics of AD. Unlike APP/PS1 mice, APP/PS1/SREBP-2 mice exhibited early mitochondrial cholesterol loading and mGSH depletion. Moreover, ß-secretase activation and Aß accumulation, correlating with oxidative damage and neuroinflammation, were accelerated in APP/PS1/SREBP-2 mice compared with APP/PS1 mice. Triple transgenic mice displayed increased synaptotoxicity reflected by loss of synaptophysin and neuronal death, resulting in early object-recognition memory impairment associated with deficits in spatial memory. Interestingly, tau pathology was present in APP/PS1/SREBP-2 mice, manifested by increased tau hyperphosphorylation and cleavage, activation of tau kinases and neurofibrillary tangle (NFT) formation without expression of mutated tau. Importantly, in vivo treatment with the cell permeable GSH ethyl ester, which restored mGSH levels in APP/PS1/SREBP-2 mice, partially prevented the activation of tau kinases, reduced abnormal tau aggregation and Aß deposition, resulting in attenuated synaptic degeneration. Taken together, these results show that cholesterol-mediated mGSH depletion is a key event in AD progression, accelerating the onset of key neuropathological hallmarks of the disease. Thus, therapeutic approaches to recover mGSH may represent a relevant strategy in the treatment of AD.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteínas tau/metabolismo , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Colesterol/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Memória , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Neurônios/fisiologia , Estresse Oxidativo , Fosforilação , Placa Amiloide/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
12.
Am J Pathol ; 184(7): 2066-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24815354

RESUMO

Disrupted cholesterol homeostasis has been reported in Alzheimer disease and is thought to contribute to disease progression by promoting amyloid ß (Aß) accumulation. In particular, mitochondrial cholesterol enrichment has been shown to sensitize to Aß-induced neurotoxicity. However, the molecular mechanisms responsible for the increased cholesterol levels and its trafficking to mitochondria in Alzheimer disease remain poorly understood. Here, we show that endoplasmic reticulum (ER) stress triggered by Aß promotes cholesterol synthesis and mitochondrial cholesterol influx, resulting in mitochondrial glutathione (mGSH) depletion in older age amyloid precursor protein/presenilin-1 (APP/PS1) mice. Mitochondrial cholesterol accumulation was associated with increased expression of mitochondrial-associated ER membrane proteins, which favor cholesterol translocation from ER to mitochondria along with specific cholesterol carriers, particularly the steroidogenic acute regulatory protein. In vivo treatment with the ER stress inhibitor 4-phenylbutyric acid prevented mitochondrial cholesterol loading and mGSH depletion, thereby protecting APP/PS1 mice against Aß-induced neurotoxicity. Similar protection was observed with GSH ethyl ester administration, which replenishes mGSH without affecting the unfolded protein response, thus positioning mGSH depletion downstream of ER stress. Overall, these results indicate that Aß-mediated ER stress and increased mitochondrial cholesterol trafficking contribute to the pathologic progression observed in old APP/PS1 mice, and that ER stress inhibitors may be explored as therapeutic agents for Alzheimer disease.


Assuntos
Peptídeos beta-Amiloides/efeitos adversos , Colesterol/metabolismo , Estresse do Retículo Endoplasmático , Mitocôndrias/metabolismo , Doença de Alzheimer/patologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Glutationa/metabolismo , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos Transgênicos , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
13.
J Pineal Res ; 59(3): 292-307, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26201382

RESUMO

Endoplasmic reticulum (ER) is a dynamic organelle that participates in a number of cellular functions by controlling lipid metabolism, calcium stores, and proteostasis. Under stressful situations, the ER environment is compromised, and protein maturation is impaired; this causes misfolded proteins to accumulate and a characteristic stress response named unfolded protein response (UPR). UPR protects cells from stress and contributes to cellular homeostasis re-establishment; however, during prolonged ER stress, UPR activation promotes cell death. ER stressors can modulate autophagy which in turn, depending of the situation, induces cell survival or death. Interactions of different autophagy- and apoptosis-related proteins and also common signaling pathways have been found, suggesting an interplay between these cellular processes, although their dynamic features are still unknown. A number of pathologies including metabolic, neurodegenerative and cardiovascular diseases, cancer, inflammation, and viral infections are associated with ER stress, leading to a growing interest in targeting components of the UPR as a therapeutic strategy. Melatonin has a variety of antioxidant, anti-inflammatory, and antitumor effects. As such, it modulates apoptosis and autophagy in cancer cells, neurodegeneration and the development of liver diseases as well as other pathologies. Here, we review the effects of melatonin on the main ER stress mechanisms, focusing on its ability to regulate the autophagic and apoptotic processes. As the number of studies that have analyzed ER stress modulation by this indole remains limited, further research is necessary for a better understanding of the crosstalk between ER stress, autophagy, and apoptosis and to clearly delineate the mechanisms by which melatonin modulates these responses.


Assuntos
Autofagia/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Melatonina/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Autofagia/genética , Estresse do Retículo Endoplasmático/genética , Humanos
14.
J Pineal Res ; 59(2): 178-89, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25975536

RESUMO

Autophagy is a process that maintains homeostasis during stress, although it also contributes to cell death under specific contexts. Ceramides have emerged as important effectors in the regulation of autophagy, mediating the crosstalk with apoptosis. Melatonin induces apoptosis of cancer cells; however, its role in autophagy and ceramide metabolism has yet to be clearly elucidated. This study was aimed to evaluate the effect of melatonin administration on autophagy and ceramide metabolism and its possible link with melatonin-induced apoptotic cell death in hepatocarcinoma (HCC) cells. Melatonin (2 mm) transiently induced autophagy in HepG2 cells through JNK phosphorylation, characterized by increased Beclin-1 expression, p62 degradation, and LC3II and LAMP-2 colocalization, which translated in decreased cell viability. Moreover, ATG5 silencing sensitized HepG2 cells to melatonin-induced apoptosis, suggesting a dual role of autophagy in cell death. Melatonin enhanced ceramide levels through both de novo synthesis and acid sphingomyelinase (ASMase) stimulation. Serine palmitoyltransferase (SPT) inhibition with myriocin prevented melatonin-induced autophagy and ASMase inhibition with imipramine-impaired autophagy flux. However, ASMase inhibition partially protected HepG2 cells against melatonin, while SPT inhibition significantly enhanced cell death. Findings suggest a crosstalk between SPT-mediated ceramide generation and autophagy in protecting against melatonin, while specific ASMase-induced ceramide production participates in melatonin-mediated cell death. Thus, dual blocking of SPT and autophagy emerges as a potential strategy to potentiate the apoptotic effects of melatonin in liver cancer cells.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Ceramidas/metabolismo , Neoplasias Hepáticas/metabolismo , Melatonina/farmacologia , Ceramidas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas de Neoplasias/metabolismo
15.
J Hepatol ; 61(5): 1126-34, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24946279

RESUMO

BACKGROUND & AIMS: Acid sphingomyelinase (ASMase) is activated in non-alcoholic steatohepatitis (NASH). However, the contribution of ASMase to NASH is poorly understood and limited to hepatic steatosis and glucose metabolism. Here we examined the role of ASMase in high fat diet (HFD)-induced NASH. METHODS: Autophagy, endoplasmic reticulum (ER) stress and lysosomal membrane permeabilization (LMP) were determined in ASMase(-/-) mice fed a HFD. The impact of pharmacological ASMase inhibition on NASH was analyzed in wild type mice fed a HFD. RESULTS: ASMase deficiency determined resistance to hepatic steatosis mediated by a HFD or methionine-choline deficient diet. ASMase(-/-) mice were resistant to HFD-induced hepatic ER stress, but sensitive to tunicamycin-mediated ER stress, indicating selectivity in the resistance of ASMase(-/-) mice to ER stress and steatosis. Autophagic flux, determined in the presence of rapamycin and/or chloroquine, was lower in primary mouse hepatocytes (PMH) from ASMase(-/-) mice and accompanied by increased p62 levels, suggesting autophagic impairment. Moreover, autophagy suppression by chloroquine and brefeldin A caused ER stress in PMH from ASMase(+/+) mice but not in ASMase(-/-) mice. ASMase(-/-) PMH exhibited increased lysosomal cholesterol loading, decreased LMP and apoptosis resistance induced by O-methyl-serine dodecylamide hydrochloride or palmitic acid, effects that were reversed by decreasing cholesterol levels by oxysterol 25-hydroxycholesterol. In vivo pharmacological ASMase inhibition by amitriptyline, a widely used tricyclic antidepressant, protected wild type mice against HFD-induced hepatic steatosis, fibrosis, and liver damage, effects indicative of early-stage NASH. CONCLUSIONS: These findings underscore a critical role for ASMase in diet-induced NASH and suggest the potential of amitriptyline as a treatment for patients with NASH.


Assuntos
Autofagia/fisiologia , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Esfingomielina Fosfodiesterase/metabolismo , Amitriptilina/farmacologia , Animais , Ceramidas/metabolismo , Colesterol/metabolismo , Deficiência de Colina/complicações , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Humanos , Fígado/metabolismo , Fígado/patologia , Lisossomos/metabolismo , Metionina/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Permeabilidade , Esfingomielina Fosfodiesterase/deficiência , Esfingomielinas/metabolismo
16.
J Clin Psychol Med Settings ; 21(2): 190-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24801493

RESUMO

The significant role of psychosocial factors in the management of type 1 diabetes in youth has been well documented. The International Society for Pediatric and Adolescent Diabetes (ISPAD) therefore published the Clinical Practice Consensus Guidelines for psychological care of young patients. However, it is unclear if and how these guidelines are being implemented. A questionnaire was created to assess implementation of the guidelines and directed to physicians through the ISPAD listserve via a web-based survey. One hundred fifty-five participants from 47 countries completed the survey. Ninety-six percent of respondents reported that they work in a team with other professionals, and 95 % of teams discuss psychological difficulties associated with diabetes management. Seventy-two percent of respondents reported having "easy access" to a mental health specialist (MHS). In 56 % of practice settings, the MHS is considered to be part of the team; 43 % participate in routine clinic visits and 26 % see all patients. Seventy percent screen for psychological problems and 57 % assess family functioning. Psychosocial or behavioral interventions addressing psychosocial and regimen adherence difficulties are offered by 79 % of teams. Psychological care is available for many children with diabetes worldwide. Yet, nearly 30 % of teams do not have access to a MHS. More training in the recognition of psychosocial problems and counseling skills is warranted. More advocacy is needed to increase availability and utilization of psychological services in routine diabetes care.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Diabetes Mellitus Tipo 1/psicologia , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Apoio Social , Criança , Família/psicologia , Humanos , Internacionalidade , Inquéritos e Questionários
17.
BMC Prim Care ; 25(1): 30, 2024 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245674

RESUMO

BACKGROUND: In the United States, Latinos face a wide array of cultural and structural barriers to accessing and utilizing mental health care. Latino men specifically are at high risk of receiving inadequate mental health care, possibly due to additional obstacles they experience that are related to masculinity. Among men more generally, greater adherence to emotional control and self-reliance is associated with higher depression severity and less depression help-seeking. Men experience more stigma toward depression and help-seeking and are less likely to be diagnosed with depression than women. However, Latino men's barriers and facilitators to depression care remain largely unexplored. The objective of this study was to examine barriers and facilitators to depression care that are related to masculinity among English- and Spanish-speaking Latino men in a primary care setting. METHODS: We used convenience and purposive sampling to recruit primary care patients who self-identified as Latino men, spoke English or Spanish, and screened positive for depressive symptoms on the Patient Health Questionnaire-2 or had a history of depression. Semi-structured interviews were conducted between December 2020 and August 2021. The interview guide examined views and experiences of depression, masculinity, and barriers and facilitators to engaging in depression care. Utilizing consensual qualitative research and thematic analysis informed by modified grounded theory, barriers and facilitators to depression care were identified. RESULTS: We interviewed thirteen participants who varied in English proficiency, education, income, and country of origin. Barriers and facilitators were placed into three domains-Self-Recognition of Depression, Seeking Help for Depression, and Depression Diagnosis and Treatment. Participants described aspects of masculinity as barriers (emotional control and pressure to provide), facilitators (honesty, courage, collaboration, practicality, and responsibility), or both (self-reliance and autonomy). CONCLUSIONS: Masculinity influences barriers and facilitators for depression care among Latino men at the levels of self-recognition, seeking help, and diagnosis and treatment. Clinicians may promote Latino men's engagement in depression care by understanding patients' values and framing depression care as affirming masculinity. Providing education to primary care physicians and other healthcare professionals on gender and depression and addressing structural barriers are essential to providing access to all who need depression care.


Assuntos
Depressão , Aceitação pelo Paciente de Cuidados de Saúde , Masculino , Humanos , Feminino , Depressão/diagnóstico , Depressão/terapia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Homens/psicologia , Pesquisa Qualitativa , Atenção Primária à Saúde
18.
Psychiatr Serv ; 75(7): 667-677, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38410039

RESUMO

OBJECTIVE: Although evidence supports the effectiveness of psychological interventions for prevention of anxiety, little is known about their cost-effectiveness. The aim of this study was to conduct a systematic review of health-economic evaluations of psychological interventions for anxiety prevention. METHODS: PubMed, PsycInfo, Web of Science, Embase, Cochrane Central Register of Controlled Trials, EconLit, National Health Service (NHS) Economic Evaluations Database, NHS Health Technology Assessment, and OpenGrey databases were searched electronically on December 23, 2022. Included studies focused on economic evaluations based on randomized controlled trials of psychological interventions to prevent anxiety. Study data were extracted, and the quality of the selected studies was assessed by using the Consensus on Health Economic Criteria and the Cochrane risk-of-bias tool. RESULTS: All included studies (N=5) had economic evaluations that were considered to be of good quality. In two studies, the interventions showed favorable cost-effectiveness compared with usual care groups. In one study, the intervention was not cost-effective. Findings from another study cast doubt on the cost-effectiveness of the intervention, and the cost-effectiveness of the intervention in the remaining study could not be established. CONCLUSIONS: Although the findings suggest some preliminary evidence of cost-effectiveness of psychological interventions for preventing anxiety, they were limited by the small number of included studies. Additional research on the cost-effectiveness of psychological interventions for anxiety in different countries and populations is required.


Assuntos
Análise Custo-Benefício , Intervenção Psicossocial , Humanos , Ansiedade/prevenção & controle , Transtornos de Ansiedade/prevenção & controle , Transtornos de Ansiedade/economia , Transtornos de Ansiedade/terapia , Intervenção Psicossocial/métodos , Intervenção Psicossocial/economia
19.
J Clin Med ; 13(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38337383

RESUMO

(1) Background: The morphology of the pelvic cavity is important for decision-making in obstetrics. This study aimed to estimate the accuracy and reliability of pelvimetry measures obtained when radiologists manually label anatomical landmarks on three-dimensional (3D) pelvic models. A second objective was to design an automatic labeling method. (2) Methods: Three operators segmented 10 computed tomography scans each. Three radiologists then labeled 12 anatomical landmarks on the pelvic models, which allowed for the calculation of 15 pelvimetry measures. Additionally, an automatic labeling method was developed based on a reference pelvic model, including reference anatomical landmarks, matching the individual pelvic models. (3) Results: Heterogeneity among landmarks in radiologists' labeling accuracy was observed, with some landmarks being rarely mislabeled by more than 4 mm and others being frequently mislabeled by 10 mm or more. The propagation to the pelvimetry measures was limited; only one out of the 15 measures reported a median error above 5 mm or 5°, and all measures showed moderate to excellent inter-radiologist reliability. The automatic method outperformed manual labeling. (4) Conclusions: This study confirmed the suitability of pelvimetry measures based on manual labeling of 3D pelvic models. Automatic labeling offers promising perspectives to decrease the demand on radiologists, standardize the labeling, and describe the pelvic cavity in more detail.

20.
J Hepatol ; 59(4): 805-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23707365

RESUMO

BACKGROUND & AIMS: The pathogenesis of alcohol-induced liver disease (ALD) is poorly understood. Here, we examined the role of acid sphingomyelinase (ASMase) in alcohol induced hepatic endoplasmic reticulum (ER) stress, a key mechanism of ALD. METHODS: We examined ER stress, lipogenesis, hyperhomocysteinemia, mitochondrial cholesterol (mChol) trafficking and susceptibility to LPS and concanavalin-A in ASMase(-)(/-) mice fed alcohol. RESULTS: Alcohol feeding increased SREBP-1c, DGAT-2, and FAS mRNA in ASMase(+/+) but not in ASMase(-/-) mice. Compared to ASMase(+/+) mice, ASMase(-/-) mice exhibited decreased expression of ER stress markers induced by alcohol, but the level of tunicamycin-mediated upregulation of ER stress markers and steatosis was similar in both types of mice. The increase in homocysteine levels induced by alcohol feeding was comparable in both ASMase(+/+) and ASMase(-/-) mice. Exogenous ASMase, but not neutral SMase, induced ER stress by perturbing ER Ca(2+) homeostasis. Moreover, alcohol-induced mChol loading and StARD1 overexpression were blunted in ASMase(-/-) mice. Tunicamycin upregulated StARD1 expression and this outcome was abrogated by tauroursodeoxycholic acid. Alcohol-induced liver injury and sensitization to LPS and concanavalin-A were prevented in ASMase(-/-) mice. These effects were reproduced in alcohol-fed TNFR1/R2(-/-) mice. Moreover, ASMase does not impair hepatic regeneration following partial hepatectomy. Of relevance, liver samples from patients with alcoholic hepatitis exhibited increased expression of ASMase, StARD1, and ER stress markers. CONCLUSIONS: Our data indicate that ASMase is critical for alcohol-induced ER stress, and provide a rationale for further clinical investigation in ALD.


Assuntos
Colesterol/metabolismo , Estresse do Retículo Endoplasmático , Hepatopatias Alcoólicas/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Amitriptilina/farmacologia , Animais , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hepatite Alcoólica/etiologia , Hepatite Alcoólica/metabolismo , Hepatite Alcoólica/patologia , Humanos , Hiper-Homocisteinemia/complicações , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias Hepáticas/metabolismo , Acetiltransferase N-Terminal A/metabolismo , Acetiltransferase N-Terminal E/metabolismo , Esfingomielina Fosfodiesterase/deficiência , Esfingomielina Fosfodiesterase/genética
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