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1.
Neurosci Lett ; 636: 3-8, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27150074

RESUMO

This review attempts to reconcile the present dual view of the mechanisms operating in Amyotrophic Lateral Sclerosis (ALS). On one side, oxidative stress, mitochondrial damage and protein aggregation are considered as causative of the disease, as strongly supported by evidence obtained in models based on the expression of ALS-typical mutant SOD1. On the other hand, evidence from models expressing ALS-typical mutations in RNA-binding proteins such as FUS and TDP43 indicate that mRNA (dys)metabolism is a major pathway in this disease. A critical analysis of existing literature suggests that there may be more than one point of intersection.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Animais , Humanos , Ferro/metabolismo , Mutação , Agregação Patológica de Proteínas/metabolismo , Dobramento de Proteína , RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
2.
Neurobiol Dis ; 94: 63-72, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27317832

RESUMO

TDP-43 is aggregated in patients with ALS and FLTD through mechanisms still incompletely understood. Since aggregation in the cytosol is most probably responsible for the delocalization and loss of proper RNA-binding function of TDP-43 in the nucleus, interception of the formation of aggregates may represent a useful therapeutic option. In this study, we investigated the relative importance of the N-terminal and C-terminal moieties of TDP-43 in the aggregation process and the weight of each of the six cysteine residues in determining unfolding and aggregation of the different domains. We report that cytoplasmic inclusions formed by WT and mutant TDP-43 in motor neuron-like NSC34 cells are redox-sensitive only in part, and contain at least two components, i.e. oligomers and large aggregates, that are made of different molecular species. The two N-terminal cysteine residues contribute to the seeding for the first step in oligomerization, which is then accomplished by mechanisms depending on the four cysteines in the RNA-recognition motifs. Cysteine-independent large aggregates contain unfolded isoforms of the protein, held together by unspecific hydrophobic interactions. Interestingly, truncated isoforms are entrapped exclusively in oligomers. Ab initio modeling of TDP-43 structure, molecular dynamics and molecular docking analysis indicate a differential accessibility of cysteine residues that contributes to aggregation propensity. We propose a model of TDP-43 aggregation involving cysteine-dependent and cysteine-independent stages that may constitute a starting point to devise strategies counteracting the formation of inclusions in TDP-43 proteinopathies.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Proteínas de Ligação a DNA/metabolismo , Corpos de Inclusão/metabolismo , Neurônios Motores/metabolismo , Animais , Núcleo Celular/metabolismo , Camundongos , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular
3.
Chem Biol Interact ; 183(1): 187-93, 2010 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19800873

RESUMO

We previously reported that conjugated linoleic acid (CLA), a naturally occurring fatty acid, inhibits the growth of ERalpha(+) MCF-7 and ERalpha(-) MDA-MB-231 human breast cancer cells by negative modulation of the ERK/MAPK pathway and apoptosis induction. Here we show that in these cell lines CLA also down-regulates the PI3K/Akt cascade. In MCF-7 cells CLA also triggers ERalpha/PP2A complex formation reducing the phosphorylation state and transcriptional activity of Eralpha whereas in MDA-MB-231 cells CLA does not induce PP2A activation. Moreover, CLA induces the expression of proteins involved in cell adhesion and inhibits cell migration and MMP-2 activity. These findings suggest that CLA may induce the down-regulation of ERalpha signalling and the reduction of cell invasion through the modulation of balancing between phosphatases and kinases.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/metabolismo , Ácidos Linoleicos Conjugados/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apoptose , Neoplasias da Mama/enzimologia , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Regulação para Baixo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Invasividade Neoplásica , Proteína Fosfatase 2/metabolismo , Transdução de Sinais
4.
Braz J Biol ; 69(3): 957-62, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19802458

RESUMO

This work evaluated the acute inflammatory response induced by injections of 0.5 mL saline solution (control), 500 microg carrageenin and 0.5 mL thioglycollate 3% in the swim bladder of juvenile tambacu hybrid. Fish were distributed in three treatments, three replications and acclimated for a period of 10 days before assay. The cell characterization from the inflammatory exudate was performed in Giemsa and PAS stained smears. Carrageenin, injected in fish, showed an increase on the total number of cells in the inflammatory exudate when compared to saline and thioglycollate injected. Whereas, for carrageenin-injected fish, the percentage of thrombocyte was higher than thioglycollate. On the other hand, granulocyte percentage in thioglycollate-injected fish was higher than the ones injected using carrageenin. Carrageenin provoked the highest migration of macrophage to the inflammatory site. The PAS method confirmed the presence of three types of granulocytes: eosinophilic granular cell (EGC) type 1 with the characteristics of a special granulocytic cell commonly found in the circulating blood; EGC type 2 shorter than the last one and neutrophil. This study contributes to a better understanding of the inflammatory response and infectious processes in native fish.


Assuntos
Células Sanguíneas/imunologia , Movimento Celular/imunologia , Exsudatos e Transudatos/imunologia , Doenças dos Peixes/imunologia , Peixes/imunologia , Inflamação/veterinária , Doença Aguda , Animais , Carragenina , Quimera , Feminino , Doenças dos Peixes/induzido quimicamente , Doenças dos Peixes/patologia , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/patologia , Masculino , Tioglicolatos
5.
Braz. j. biol ; 69(3): 957-962, Aug. 2009. ilus, graf
Artigo em Inglês | LILACS | ID: lil-527166

RESUMO

This work evaluated the acute inflammatory response induced by injections of 0.5 mL saline solution (control), 500 µg carrageenin and 0.5 mL thioglycollate 3 percent in the swim bladder of juvenile tambacu hybrid. Fish were distributed in three treatments, three replications and acclimated for a period of 10 days before assay. The cell characterization from the inflammatory exudate was performed in Giemsa and PAS stained smears. Carrageenin, injected in fish, showed an increase on the total number of cells in the inflammatory exudate when compared to saline and thioglycollate injected. Whereas, for carrageenin-injected fish, the percentage of thrombocyte was higher than thioglycollate. On the other hand, granulocyte percentage in thioglycollate-injected fish was higher than the ones injected using carrageenin. Carrageenin provoked the highest migration of macrophage to the inflammatory site. The PAS method confirmed the presence of three types of granulocytes: eosinophilic granular cell (EGC) type 1 with the characteristics of a special granulocytic cell commonly found in the circulating blood; EGC type 2 shorter than the last one and neutrophil. This study contributes to a better understanding of the inflammatory response and infectious processes in native fish.


Este estudo avaliou a resposta inflamatória aguda induzida por injeções de 0,5 mL de solução salina (controle), 500 µg de carragenina e 0,5 mL de tioglicolato a 3 por cento na bexiga natatória de juvenis do híbrido tambacu. Os peixes foram distribuídos em três tratamentos, três repetições e aclimatados durante 10 dias antes do ensaio. A caracterização das células do exsudato inflamatório foi feita após coloração com Giemsa e PAS. Peixes injetados com carragenina apresentaram maior número de células no exsudato inflamatório do que com salina e tioglicolato. A porcentagem de trombócitos no exsudato foi maior nos injetados com carragenina quando comparada com a dos injetados com tioglicolato. Por outro lado, o percentual de granulócitos foi maior em animais injetados com tioglicolato do que em animais injetados com carragenina. A carragenina provocou maior migração de macrófagos para o foco inflamatório. O método de PAS confirmou a presença de três tipos de granulócitos: célula granular eosinofílica (CGE) tipo 1 com as características da célula granulocítica especial encontrada no sangue, CGE tipo 2, menor do que esta última, e de neutrófilos. Este estudo contribui para o melhor entendimento da resposta inflamatória e dos processos infecciosos em peixes nativos.


Assuntos
Animais , Feminino , Masculino , Células Sanguíneas/imunologia , Movimento Celular/imunologia , Exsudatos e Transudatos/imunologia , Doenças dos Peixes/imunologia , Peixes/imunologia , Inflamação/veterinária , Doença Aguda , Carragenina , Quimera , Doenças dos Peixes/induzido quimicamente , Doenças dos Peixes/patologia , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/patologia , Tioglicolatos
6.
Parasite ; 9(2): 175-80, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12116864

RESUMO

The present work, studied the effect of 0, 1,000, 1,500 and 2,000 mg of garlic powder/kg dry ration for Piaractus mesopotamicus (Osteichthyes: Characidae), weighting 73.6 +/- 39.4 g and measuring 15.0 +/- 2.7 cm, fed for a period of 15, 30 and 45 days. Fifteen days after treatment with 1,000 and 2,000 mg of garlic/kg dry ration, significant reduction of Anacanthorus penilabiatus (Monogenea: Dactylogyridae) in the gills was related. Nevertheless, the addition of garlic to the ration caused significant increase in the erythrocyte number and in the thrombocyte percentage in the circulating blood. However, a decrease in the lymphocyte percentage was also observed. After 45 days, fish fed with garlic showed significant increase in the erythrocyte number, leucocyte, haemoglobin rate, hematocrit and thrombocyte.


Assuntos
Doenças dos Peixes/dietoterapia , Alho , Helmintíase Animal/dietoterapia , Fitoterapia/veterinária , Extratos Vegetais/uso terapêutico , Ração Animal , Animais , Brasil , Relação Dose-Resposta a Droga , Contagem de Eritrócitos , Doenças dos Peixes/sangue , Pesqueiros , Peixes/crescimento & desenvolvimento , Peixes/parasitologia , Brânquias/parasitologia , Helmintíase Animal/sangue , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Contagem de Plaquetas , Platelmintos/fisiologia , Poluição da Água/prevenção & controle
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