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1.
Free Radic Biol Med ; 162: 202-215, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33096249

RESUMO

Hyptis suaveolens (HS), Hyptis pectinata (HP) and Hyptis marrubioides (HM) are plants used in folk medicine for treatment of several diseases. Here, we tested the in vivo antioxidant and neuroprotective potential of methanolic extracts from these plants, containing several rosmarinic acid derivatives and isoquercetin. In C. elegans, HS, HP and HM leaf extracts enhanced the antioxidant responses through the induction of specific antioxidant enzymes and demonstrated neurotherapeutic potential in transgenic models of genetically determined human neurodegenerative diseases - Frontotemporal dementia with parkinsonism linked to chromosome 17 and Machado-Joseph disease. Chronic treatment of disease models with HS, HP and HM leaf extracts improved the animals' motor function and increased their tolerance to an oxidative insult. The restorative effect of HM extract in motor performance of both disease models required the presence of glutathione reductase (gsr-1), an enzyme that assures the glutathione redox cycle, highlighting the role of this pathway and unveiling a common candidate therapeutic target for these diseases. Our findings strengthen the relevance of plant-derived bioactive compound discovery for neurodegenerative disorders that remain without effective treatment.


Assuntos
Glutationa , Hyptis , Extratos Vegetais/farmacologia , Tauopatias , Animais , Caenorhabditis elegans/genética , Oxirredução , Peptídeos , Tauopatias/tratamento farmacológico , Tauopatias/genética
2.
Data Brief ; 33: 106598, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33318982

RESUMO

Here, we present the data on the biological effects of Hyptis spp. and Lycium spp. plant extracts in Caenorhabditis elegans (C. elegans) models of neurodegenerative diseases, which is related to the work presented in the article "Neurotherapeutic effect of Hyptis spp. leaf extracts in C. elegans models of tauopathy and polyglutamine disease: role of the glutathione redox cycle" [1]. This dataset was generated to define non-toxic concentrations of these plant extracts and to assess their impact on the motor phenotype and oxidative stress resistance of transgenic C. elegans models of two genetically defined neurodegenerative diseases: Machado-Joseph disease and Frontotemporal dementia with Parkinsonism associated to the chromosome 17. The impact of the plant extracts on toxicity was assessed using the food-clearance assay, absorbance being measured daily for seven days at 595 nm to quantify Escherichia coli (E. coli) strain OP50 bacteria consumption. Worm length and motor behaviour, including spontaneous and stimulated movement, were analysed using videos acquired with an Olympus SZX7 stereomicroscope with an integrated camera (Olympus SC30) and processed using the Image J® software and the Wrmtrck plugin. The resistance to oxidative stress induced by 240 µM juglone was assessed by determining the percentage of live animals after 1 hour of exposure.

3.
Cell Mol Life Sci ; 75(11): 2027-2044, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29196797

RESUMO

The sorting nexins family of proteins (SNXs) plays pleiotropic functions in protein trafficking and intracellular signaling and has been associated with several disorders, namely Alzheimer's disease and Down's syndrome. Despite the growing association of SNXs with neurodegeneration, not much is known about their function in the nervous system. The aim of this work was to use the nematode Caenorhabditis elegans that encodes in its genome eight SNXs orthologs, to dissect the role of distinct SNXs, particularly in the nervous system. By screening the C. elegans SNXs deletion mutants for morphological, developmental and behavioral alterations, we show here that snx-3 gene mutation leads to an array of developmental defects, such as delayed hatching, decreased brood size and life span and reduced body length. Additionally, ∆snx-3 worms present increased susceptibility to osmotic, thermo and oxidative stress and distinct behavioral deficits, namely, a chemotaxis defect which is independent of the described snx-3 role in Wnt secretion. ∆snx-3 animals also display abnormal GABAergic neuronal architecture and wiring and altered AIY interneuron structure. Pan-neuronal expression of C. elegans snx-3 cDNA in the ∆snx-3 mutant is able to rescue its locomotion defects, as well as its chemotaxis toward isoamyl alcohol. Altogether, the present work provides the first in vivo evidence of the SNX-3 role in the nervous system.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/genética , Deleção de Genes , Nexinas de Classificação/genética , Animais , Tamanho Corporal , Caenorhabditis elegans/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Locomoção , Longevidade , Sistema Nervoso/crescimento & desenvolvimento , Sistema Nervoso/metabolismo , Fenômenos Fisiológicos do Sistema Nervoso , Neurônios/metabolismo , Neurônios/patologia , Pressão Osmótica , Estresse Oxidativo , Filogenia
4.
Brain ; 138(Pt 11): 3221-37, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26373603

RESUMO

Polyglutamine diseases are a class of dominantly inherited neurodegenerative disorders for which there is no effective treatment. Here we provide evidence that activation of serotonergic signalling is beneficial in animal models of Machado-Joseph disease. We identified citalopram, a selective serotonin reuptake inhibitor, in a small molecule screen of FDA-approved drugs that rescued neuronal dysfunction and reduced aggregation using a Caenorhabditis elegans model of mutant ataxin 3-induced neurotoxicity. MOD-5, the C. elegans orthologue of the serotonin transporter and cellular target of citalopram, and the serotonin receptors SER-1 and SER-4 were strong genetic modifiers of ataxin 3 neurotoxicity and necessary for therapeutic efficacy. Moreover, chronic treatment of CMVMJD135 mice with citalopram significantly reduced ataxin 3 neuronal inclusions and astrogliosis, rescued diminished body weight and strikingly ameliorated motor symptoms. These results suggest that small molecule modulation of serotonergic signalling represents a promising therapeutic target for Machado-Joseph disease.


Assuntos
Ataxina-3/efeitos dos fármacos , Proteínas de Caenorhabditis elegans/efeitos dos fármacos , Citalopram/farmacologia , Gliose/metabolismo , Corpos de Inclusão/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Doença de Machado-Joseph/metabolismo , Neurônios/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Serotonina/metabolismo , Animais , Ataxina-3/metabolismo , Comportamento Animal/efeitos dos fármacos , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Neurônios/patologia , Proteínas da Membrana Plasmática de Transporte de Serotonina , Transmissão Sináptica/efeitos dos fármacos
5.
Orphanet J Rare Dis ; 8: 100, 2013 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-23837398

RESUMO

BACKGROUND: Rare, recurrent genomic imbalances facilitate the association of genotype with abnormalities at the "whole body" level. However, at the cellular level, the functional consequences of recurrent genomic abnormalities and how they can be linked to the phenotype are much less investigated. METHOD AND RESULTS: We report an example of a functional analysis of two genes from a new, overlapping microdeletion of 2p13.2 region (from 72,140,702-72,924,626). The subjects shared intellectual disability (ID), language delay, hyperactivity, facial asymmetry, ear malformations, and vertebral and/or craniofacial abnormalities. The overlapping region included two genes, EXOC6B and CYP26B1, which are involved in exocytosis/Notch signaling and retinoic acid (RA) metabolism, respectively, and are of critical importance for early morphogenesis, symmetry as well as craniofacial, skeleton and brain development. The abnormal function of EXOC6B was documented in patient lymphoblasts by its reduced expression and with perturbed expression of Notch signaling pathway genes HES1 and RBPJ, previously noted to be the consequence of EXOC6B dysfunction in animal and cell line models. Similarly, the function of CYP26B1 was affected by the deletion since the retinoic acid induced expression of this gene in patient lymphoblasts was significantly lower compared to controls (8% of controls). CONCLUSION: Haploinsufficiency of CYP26B1 and EXOC6B genes involved in retinoic acid and exocyst/Notch signaling pathways, respectively, has not been reported previously in humans. The developmental anomalies and phenotypic features of our subjects are in keeping with the dysfunction of these genes, considering their known role. Documenting their dysfunction at the cellular level in patient cells enhanced our understanding of biological processes which contribute to the clinical phenotype.


Assuntos
Doenças do Desenvolvimento Ósseo/genética , Deleção Cromossômica , Cromossomos Humanos Par 2/genética , Anormalidades Craniofaciais/genética , Deficiências do Desenvolvimento/genética , Haploinsuficiência , Anormalidades Múltiplas/genética , Adolescente , Doenças do Desenvolvimento Ósseo/patologia , Linhagem Celular , Criança , Anormalidades Craniofaciais/patologia , Sistema Enzimático do Citocromo P-450/genética , Deficiências do Desenvolvimento/patologia , Exocitose/genética , Proteínas de Ligação ao GTP/genética , Genótipo , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Ácido Retinoico 4 Hidroxilase , Tretinoína/metabolismo
6.
Mol Neurobiol ; 48(3): 465-89, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23494747

RESUMO

Neurodevelopmental disorders such as epilepsy, intellectual disability (ID), and autism spectrum disorders (ASDs) occur in over 2 % of the population, as the result of genetic mutations, environmental factors, or combination of both. In the last years, use of large-scale genomic techniques allowed important advances in the identification of genes/loci associated with these disorders. Nevertheless, following association of novel genes with a given disease, interpretation of findings is often difficult due to lack of information on gene function and effect of a given mutation in the corresponding protein. This brings the need to validate genetic associations from a functional perspective in model systems in a relatively fast but effective manner. In this context, the small nematode, Caenorhabditis elegans, presents a good compromise between the simplicity of cell models and the complexity of rodent nervous systems. In this article, we review the features that make C. elegans a good model for the study of neurodevelopmental diseases. We discuss its nervous system architecture and function as well as the molecular basis of behaviors that seem important in the context of different neurodevelopmental disorders. We review methodologies used to assess memory, learning, and social behavior as well as susceptibility to seizures in this organism. We will also discuss technological progresses applied in C. elegans neurobiology research, such as use of microfluidics and optogenetic tools. Finally, we will present some interesting examples of the functional analysis of genes associated with human neurodevelopmental disorders and how we can move from genes to therapies using this simple model organism.


Assuntos
Caenorhabditis elegans/crescimento & desenvolvimento , Doenças do Sistema Nervoso/patologia , Sistema Nervoso/crescimento & desenvolvimento , Sistema Nervoso/patologia , Animais , Modelos Animais de Doenças , Humanos , Memória , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/fisiopatologia , Doenças do Sistema Nervoso/terapia , Comportamento Social
7.
Hum Mutat ; 31(3): 356-65, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20052765

RESUMO

Neuronal ceroid lipofuscinoses (NCLs) represent a group of children's inherited neurodegenerative disorders caused by mutations in at least eight different genes. Mutations in the CLN5 gene result in the Finnish variant late infantile NCL characterized by gradual loss of vision, epileptic seizures, and mental deterioration. The CLN5 gene encodes a lysosomal glycoprotein of unidentified function. In this study, we have used both transient and stable expression systems for the characterization of CLN5, focusing on the localization, processing, and intracellular trafficking. We show that CLN5 is proteolytically cleaved, and that the mature polypeptide is transported to the lysosomes. Our data provide the first evidence that soluble CLN5 protein can also undergo mannose-6-phosphate receptor-independent trafficking to the lysosomes. We studied the localization and maturation of the CLN5 carrying the previously uncharacterized vLINCL disease causing mutations in HeLa cells. All analyzed disease mutations disturb the lysosomal trafficking of the mutated CLN5 proteins. The level of lysosomal targeting does not correlate, however, to disease onset, indicating that CLN5 may also function outside lysosomes. This study furthers our understanding of the basic properties of the CLN5 protein, necessary for the characterization of the consequences of disease mutations and for the planning of future therapies for vLINCL.


Assuntos
Proteínas de Membrana/metabolismo , Mutação , Lipofuscinoses Ceroides Neuronais/genética , Lipofuscinoses Ceroides Neuronais/metabolismo , Animais , Células COS , Chlorocebus aethiops , Análise Mutacional de DNA , DNA Complementar/metabolismo , Regulação da Expressão Gênica , Glicoproteínas/metabolismo , Células HeLa , Humanos , Proteínas de Membrana Lisossomal , Lisossomos/metabolismo , Proteínas de Membrana/genética , Modelos Biológicos , Proteínas Recombinantes/química
8.
J Neurol ; 250(6): 661-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12796825

RESUMO

A series of 53 Portuguese patients (derived from 43 families) born in the period 1963-1999 have been diagnosed with neuronal ceroid lipofuscinosis (NCL) based on clinicopathological findings. Plotting the cumulative number of new cases per year against the year of birth resulted in a slightly S-shaped curve, with a nearly straight central segment over a period of 14 years (1977-1990) indicating a continuous registration of new cases born during the corresponding time period. In this period the prevalence of overall NCL in the Portuguese population was calculated to be 1.55 per 100.000 live births.Twenty-six patients from 20 unrelated families were further evaluated by combining clinicopathological with biochemical and genetic data. No intra-familial heterogeneity was observed. Four sub-types of childhood NCL were identified: infantile NCL (INCL) with granular osmiophilic inclusions (GROD) and PPT1 deficiency (1/26), classical LINCL with curvilinear (CV) inclusions and tripeptidyl peptidase (TPP1) deficiency (3/26), variant late infantile NCL (LINCL) with fingerprint/curvilinear (FP/CV) inclusions and normal TPP1 enzyme activity (11/26) and juvenile NCL (JNCL) with a mix of FP/CV (11/26). Eight of 11 JNCL patients were homozygous for the 1.02-kb deletion in the CLN3 gene, and 3 were heterozygous with an unidentified mutation in the second allele. The 1.02-kb deletion in the CLN3 gene accounted for 86.3 % (19/22) of CLN3-causing alleles and 36.5 % (19/52) of childhood NCL defects. The causal mutations for CLN1 and CLN2 were V181M (2/2) and R208X (4/6), respectively. CLN1, CLN2 and CLN3 affected 3.8 %, 11.5 % and 42.3 % of NCL Portuguese patients, respectively. In 42.3 % of patients affected by the vLINCL form, CLN3, CLN5 and CLN8 gene defects were excluded by direct sequencing of cDNA. Genetic variants such as CLN6 might therefore cause a significant portion of childhood NCL in the Portuguese population. The relative frequency of classical childhood forms of NCL in the Portuguese population is reported and contributes to the knowledge of genetic epidemiology of these world-widely distributed disorders.


Assuntos
Lipofuscinoses Ceroides Neuronais , Adolescente , Adulto , Idade de Início , Alelos , Aminopeptidases , Células Cultivadas , Criança , Pré-Escolar , Análise Mutacional de DNA , Dipeptidil Peptidases e Tripeptidil Peptidases , Endopeptidases , Feminino , Fibroblastos/enzimologia , Ligação Genética , Variação Genética , Genética Populacional , Humanos , Lisossomos/ultraestrutura , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia Eletrônica , Mutação , Lipofuscinoses Ceroides Neuronais/epidemiologia , Lipofuscinoses Ceroides Neuronais/genética , Lipofuscinoses Ceroides Neuronais/metabolismo , Lipofuscinoses Ceroides Neuronais/fisiopatologia , Linhagem , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Polimorfismo Conformacional de Fita Simples , Portugal/epidemiologia , Estudos Retrospectivos , Serina Proteases , Pele/enzimologia , Pele/ultraestrutura , Glândulas Sudoríparas/ultraestrutura , Tioléster Hidrolases , Tripeptidil-Peptidase 1
9.
Hum Mutat ; 21(5): 502-8, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12673792

RESUMO

The neuronal ceroid lipofuscinoses (NCLs) are a heterogeneous group of autosomal recessive neurodegenerative diseases comprising Batten and other related diseases plus numerous variants. They are characterized by progressive neuronal cell death. The CLN6 gene was recently identified, mutations in which cause one of the variant late infantile forms of NCL (vLINCL). We describe four novel mutations in the CLN6 gene. This brings the total number of CLN6 mutations known to 11 in 38 families. This suggests that the CLN6 gene may be highly mutable. An American patient of Irish/French/Native American origin was heterozygous for a 4-bp insertion (c.267_268insAACG) in exon 3. The other allele had a point mutation (c.898T>C) in exon 7 resulting in a W300R amino acid change. Two Trinidadian siblings of Indian origin were homozygous for a mutation at the 5' donor splice site of exon 4 (IVS4+1G>T), affecting the first base of the invariant GT at the beginning of intron 4. The fourth novel mutation, a double deletion of 4 bp and 1 bp in exon 7 (c.829_832delGTCG;c.837delG), was identified in a Portuguese patient heterozygous for the I154del Portuguese CLN6 mutation. Four of the 11 mutations identified are in exon 4. Three Portuguese patients with clinical profiles similar to CLN6 patients without defects in CLN6 or other known NCL genes are described. We conclude the following: 1) the CLN6 gene may be a highly mutable gene; 2) exon 4 must code for a segment of the protein crucial for function; 3) vLINCL disease in Portugal is genetically heterogeneous; 4) the I154del accounts for 81.25% of affected CLN6 Portuguese alleles; and 5) three vLINCL Portuguese patients may have defects in a new NCL gene.


Assuntos
Proteínas de Membrana/genética , Lipofuscinoses Ceroides Neuronais/genética , Sequência de Bases , DNA/química , DNA/genética , Análise Mutacional de DNA , Humanos , Lactente , Mutação
10.
An. oftalmol ; 8(1): 33-7, abr. 1989. ilus
Artigo em Português | LILACS | ID: lil-89117

RESUMO

O autor descreve as principais vantagens de lentes multifocais progressivas para a correçäo de ametropias associadas a presbiopia, demonstrando a superioridade da imagem propiciada pelas mesmas. Os cuidados com a prescriçäo, montagem e verificaçäo das lentes säo descritos


Assuntos
Presbiopia/terapia , Lentes , Erros de Refração
11.
J. bras. psiquiatr ; 1(30): 35-46, jan./fev. 1981.
Artigo | Index Psicologia - Periódicos | ID: psi-7099

RESUMO

Apresentacao de um caso clinico de psicose de feito maniforme e evolucao recorrente em paciente destro, do sexo masculino, com lesao cerebral cistica de localizacao fronto-orbital direita e de provavel origem pos-traumatica, constatada atraves de tomografia axial computorizada. Em confronto com a literatura a sintomatologia esta, em grande parte, de acordo com as descricoes do sindrome do lobo frontal nas lesoes bilaterais. Achados peculiares dignos de destaque foram a intensa atividade confabulatoria expansiva, notavelmente semelhante ao 'delirio de grandeza' da paralisia geral progressiva na transmissao dos sintomas agudos com o uso de medicamentos. Com o registro deste caso, os autores julgam poder refutar pela primeira vez, a nocao de que somente as lesoes frontais bilaterais ou as unilaterais no hemisferio dominante seriam capazes de ocasionar sintomatologia comportamental significativa.


Assuntos
Lobo Frontal , Transtornos Psicóticos , Lobo Frontal
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