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2.
Neurobiol Aging ; 35(10): 2329-46, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24775711

RESUMO

Although the support for the use of antioxidants, such as coenzyme Q(10) (CoQ(10)), to treat Parkinson's disease (PD) comes from the extensive scientific evidence, the results of conducted thus far clinical trials are inconclusive. It is assumed that the efficacy of CoQ(10) is hindered by insolubility, poor bioavailability, and lack of brain penetration. We have developed a nanomicellar formulation of CoQ(10) (Ubisol-Q(10)) with improved properties, including the brain penetration, and tested its effectiveness in mouse MPTP (1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine) model with the objectives to assess its potential use as an adjuvant therapy for PD. We used a subchronic MPTP model (5-daily MPTP injections), characterized by 50% loss of dopamine neurons over a period of 28 days. Ubisol-Q(10) was delivered in drinking water. Prophylactic application of Ubisol-Q(10), started 2 weeks before the MPTP exposure, significantly offset the neurotoxicity (approximately 50% neurons died in MPTP group vs. 17% in MPTP+ Ubisol-Q(10) group by day 28). Therapeutic application of Ubisol-Q(10), given after the last MPTP injection, was equally effective. At the time of intervention on day 5 nearly 25% of dopamine neurons were already lost, but the treatment saved the remaining 25% of cells, which otherwise would have died by day 28. This was confirmed by cell counts, analyses of striatal dopamine levels, and improved animals' motor skill on a beam walk test. Similar levels of neuroprotection were obtained with 3 different Ubisol-Q(10) concentrations tested, that is, 30 mg, 6 mg, or 3 mg CoQ(10)/kg body weight/day, showing clearly that high doses of CoQ(10) were not required to deliver these effects. Furthermore, the Ubisol-Q(10) treatments brought about a robust astrocytic activation in the brain parenchyma, indicating that astroglia played an active role in this neuroprotection. Thus, we have shown for the first time that Ubisol-Q(10) was capable of halting the neurodegeneration already in progress; however, to maintain it a continuous supplementation of Ubisol-Q(10) was required. The pathologic processes initiated by MPTP resumed if supplementation was withdrawn. We suggest that in addition to brain delivery of powerful antioxidants, Ubisol-Q(10) might have also supported subcellular oxidoreductase systems allowing them to maintain a favorable cellular redox status, especially in astroglia, facilitating their role in neuroprotection. Based on this data further clinical testing of this formulation in PD patients might be justifiable.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Antioxidantes/uso terapêutico , Micelas , Nanopartículas , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Ubiquinona/análogos & derivados , Animais , Antioxidantes/administração & dosagem , Astrócitos/metabolismo , Química Farmacêutica , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Masculino , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/administração & dosagem , Oxirredução/efeitos dos fármacos , Doença de Parkinson/patologia , Ubiquinona/administração & dosagem , Ubiquinona/uso terapêutico
3.
BMC Neurosci ; 15: 21, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24483602

RESUMO

BACKGROUND: Paraquat, still used as an herbicide in some parts of the world, is now regarded as a dangerous environmental neurotoxin and is linked to the development Parkinson's disease (PD). Paraquat interacts with cellular redox systems and causes mitochondrial dysfunction and the formation of reactive oxygen species, which in turn, plays a crucial role in the pathophysiology of PD. Various antioxidant therapies have been explored with the expectations that they deliver health benefits to the PD patients, however, no such therapies were effective. Here we have tested the neuroprotective efficacy of a novel water-soluble CoQ10 (Ubisol-Q10), in a rat model of paraquat-induced neurodegeneration in order to evaluate its potential application in the management of PD. RESULTS: We have developed a rat model of progressive nigrostriatal degeneration by giving rats five intraperitoneal injections of paraquat (10 mg/kg/injection), once every five days. Neuronal death occurred over a period of 8 weeks with close to 50% reduction in the number of tyrosine hydroxylase-positive cells. Ubisol-Q10, at 6 mg CoQ10/kg body weight/day, was delivered as a supplement in drinking water. The intervention begun after the completion of paraquat injections when the neurodegenerative process had already began and about 20% of TH-positive neurons were lost. Ubisol-Q10 treatment halted the progression of neurodegeneration and remaining neurons were protected. The outcomes were evaluated based on the number of surviving tyrosine hydroxylase-positive neurons in the substantia nigra region and improved motor skills in response to the Ubisol-Q10 intervention. To maintain this neuroprotection, however, continuous Ubisol- Q10 supplementation was required, if withdrawn, the neuronal death pathway resumed, suggesting that the presence of CoQ10 was essential for blocking the pathway. CONCLUSION: The CoQ10, given orally as Ubisol-Q10 in drinking solution, was effective in blocking the progression of neurodegeneration when administered therapeutically (post-toxin injection), at a much lower concentration than other previously tested oil soluble formulations and well within the acceptable daily intake of 12 mg/kg/day. Such unprecedented neuroprotection has never been reported before. These results are very encouraging and suggest that Ubisol-Q10 should be further tested and developed as a therapy for halting the progression of PD.


Assuntos
Neurônios/efeitos dos fármacos , Doença de Parkinson/prevenção & controle , Doença de Parkinson/fisiopatologia , Substância Negra/fisiopatologia , Ubiquinona/análogos & derivados , Administração Oral , Animais , Sobrevivência Celular/efeitos dos fármacos , Estudos de Viabilidade , Masculino , Neurônios/patologia , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/química , Paraquat , Ratos , Ratos Long-Evans , Rifabutina/análogos & derivados , Solubilidade , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Resultado do Tratamento , Ubiquinona/administração & dosagem , Ubiquinona/química , Vitaminas/administração & dosagem , Vitaminas/química , Água/química
4.
J Neurosci Methods ; 186(1): 60-7, 2010 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-19903493

RESUMO

Neuro 2A (N2a) is a mouse neural crest-derived cell line that has been extensively used to study neuronal differentiation, axonal growth and signaling pathways. A convenient characteristic of these cells is their ability to differentiate into neurons within a few days. However, most differentiation methods reported for N2a cells do not provide information about the neuronal types obtained after each treatment. In this study, we evaluated the generation of N2a dopamine neurons following treatment with a number of factors known to induce neuronal differentiation. Our results showed that N2a cells express Nurr-related factor 1 (Nurr1) and produce low levels of tyrosine hydroxylase (TH) and dopamine. Both TH and dopamine levels were significantly enhanced in the presence of dibutyryl cyclic adenosine monophosphate (dbcAMP), as evidenced by Western blot, immunocytochemistry and high performance liquid chromatography (HPLC). In contrast to dbcAMP, other factors such as transforming growth factor beta1 (TGF beta 1), bone morphogenetic protein 4 (BMP4), glial cell-derived neurotrophic factor (GDNF) and retinoic acid (RA) did not increase TH expression. Further investigation confirmed that the effect of dbcAMP on production of TH-positive neurons was mediated through cyclic AMP (cAMP) responsive element binding protein (CREB) and it was antagonized by RA. Thus, although various treatments can be used to generate N2a neurons, only dbcAMP significantly enhanced the formation of dopamine neurons. Taken together, this study provided a simple and reliable method to generate dopamine neurons for rapid and efficient physiological and pharmacological assays.


Assuntos
Diferenciação Celular/fisiologia , Dopamina/metabolismo , Neurogênese/fisiologia , Neurônios/metabolismo , Células-Tronco/metabolismo , Animais , Bucladesina/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Camundongos , Fatores de Crescimento Neural/farmacologia , Neurogênese/efeitos dos fármacos , Neurônios/citologia , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Tretinoína/metabolismo , Tretinoína/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo
5.
Muscle Nerve ; 40(3): 381-94, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19626676

RESUMO

The potential pathogenicity of two homoplasmic mtDNA point mutations, 9035T>C and 4452T>C, found in a family afflicted with maternally transmitted cognitive developmental delay, learning disability, and progressive ataxia was evaluated using transmitochondrial cybrids. We confirmed that the 4452T>C transition in tRNA(Met) represented a polymorphism; however, 9035T>C conversion in the ATP6 gene was responsible for a defective F(0)-ATPase. Accordingly, mutant cybrids had a reduced oligomycin-sensitive ATP hydrolyzing activity. They had less than half of the steady-state content of ATP and nearly an 8-fold higher basal level of reactive oxygen species (ROS). Mutant cybrids were unable to cope with additional insults, i.e., glucose deprivation or tertiary-butyl hydroperoxide, and they succumbed to either apoptotic or necrotic cell death. Both of these outcomes were prevented by the antioxidants CoQ(10) and vitamin E, suggesting that the abnormally high levels of ROS were the triggers of cell death. In conclusion, the principal metabolic defects, i.e., energy deficiency and ROS burden, resulted from the 9035T>C mutation and could be responsible for the development of clinical symptoms in this family. Furthermore, antioxidant therapy might prove helpful in the management of this disease.


Assuntos
Ataxia/genética , DNA Mitocondrial/genética , Doenças Mitocondriais/genética , Polimorfismo Genético/genética , Trifosfato de Adenosina/metabolismo , Adulto , Análise de Variância , Antioxidantes/farmacologia , Ataxia/complicações , Caspase 3/metabolismo , Linhagem Celular Transformada , Linhagem Celular Tumoral , Pré-Escolar , Transtornos Cognitivos/complicações , Transtornos Cognitivos/genética , Análise Mutacional de DNA/métodos , Deficiências do Desenvolvimento/complicações , Deficiências do Desenvolvimento/genética , Saúde da Família , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Glioblastoma/patologia , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Pessoa de Meia-Idade , Doenças Mitocondriais/complicações , Espécies Reativas de Oxigênio/metabolismo , Vitaminas/farmacologia
6.
Anal Chim Acta ; 639(1-2): 57-61, 2009 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-19345758

RESUMO

Mass spectrometry imaging has emerged as a powerful tool for the direct detection of biomolecules, mainly phospholipids, proteins and peptides, in tissue samples. To date, there is very little information available on the direct analysis of gangliosides in brain tissue. One major hurdle for imaging gangliosides in tissue using mass spectrometry is that sialic acid residues can be dissociated in ionization process. In this report, we investigated an ionic liquid matrix for mass spectrometry imaging of gangliosides. This ionic liquid matrix offered excellent sensitivity for detection gangliosides without significant loss of sialic acid residues. Thus, it can be used to study the abundance and anatomical localization of gangliosides in mouse brain using mass spectrometry imaging technique. Mass spectrometry image analyses of the mouse brain tissue sections demonstrated that the N-fatty acyl chains of gangliosides were differentially distributed in mouse hippocampal regions, whereby the gangliosides with N-C(18) acyl chain were enriched in CA1 region, while gangliosides with N-C(20) acyl chain were enriched in dentate gyrus. In addition, this observation is true for mono-, di- and tri-sialylated gangliosides. Although the linkage information was not determined, the mass spectrometry imaging technique was capable of spatial tissue mapping of ceramide structures in gangliosides.


Assuntos
Encéfalo/metabolismo , Gangliosídeos/análise , Líquidos Iônicos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Gangliosídeos/química , Gangliosídeos/metabolismo , Hipocampo/química , Hipocampo/metabolismo , Camundongos
7.
Neurobiol Dis ; 33(3): 405-14, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19118631

RESUMO

In recent years, GDNF has emerged as a protective and restorative agent in several models of neurodegeneration; however, the exact molecular mechanisms responsible for these effects are not yet fully understood. Here we examined the effects of astrocytes secreting GDNF on neurons subjected to 6OHDA toxicity using in vitro neuron-astroglia co-cultures. Astrocytes were transduced with lentiviral vectors carrying the GDNF gene under the control of either human glial fibrillary acidic protein or cytomegalovirus promoters. The overexpression of GDNF, regardless of the promoter employed, had no obvious adverse effects on astroglia and the engineered cells stably produced and secreted GDNF for extended periods of time (> or =3 weeks). These astrocytes very effectively protected neurons against 6OHDA, in both mouse and human co-culture systems. The neuroprotective effects were mediated not only by GDNF, but also by the antioxidant GSH since its depletion reduced the level of GDNF protection. Furthermore, neurons and astrocytes expressed different components of GDNF signaling complex, suggesting that they might utilize separate pathways to mediate autocrine and paracrine effects of GDNF.


Assuntos
Astrócitos/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Glutationa/metabolismo , Neurônios/fisiologia , Oxidopamina/toxicidade , Análise de Variância , Animais , Antioxidantes/metabolismo , Western Blotting , Butionina Sulfoximina/administração & dosagem , Sobrevivência Celular/fisiologia , Técnicas de Cocultura , Expressão Gênica , Glutationa/antagonistas & inibidores , Humanos , Imuno-Histoquímica , Camundongos , Neurônios/efeitos dos fármacos , Reação em Cadeia da Polimerase , Transdução de Sinais/fisiologia , Transfecção
8.
J Bacteriol ; 188(12): 4312-20, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16740937

RESUMO

Campylobacter jejuni remains the leading cause of bacterial gastroenteritis in developed countries, and yet little is known concerning the mechanisms by which this fastidious organism survives within its environment. We have demonstrated that C. jejuni 11168 can form biofilms on a variety of surfaces. Proteomic analyses of planktonic and biofilm-grown cells demonstrated differences in protein expression profiles between the two growth modes. Proteins involved in the motility complex, including the flagellins (FlaA, FlaB), the filament cap (FliD), the basal body (FlgG, FlgG2), and the chemotactic protein (CheA), all exhibited higher levels of expression in biofilms than found in stationary-phase planktonic cells. Additional proteins with enhanced expression included those involved in the general (GroEL, GroES) and oxidative (Tpx, Ahp) stress responses, two known adhesins (Peb1, FlaC), and proteins involved in biosynthesis, energy generation, and catabolic functions. An aflagellate flhA mutant not only lost the ability to attach to a solid matrix and form a biofilm but could no longer form a pellicle at the air-liquid interface of a liquid culture. Insertional inactivation of genes that affect the flagellar filament (fliA, flaA, flaB, flaG) or the expression of the cell adhesin (flaC) also resulted in a delay in pellicle formation. These findings demonstrate that the flagellar motility complex plays a crucial role in the initial attachment of C. jejuni 11168 to solid surfaces during biofilm formation as well as in the cell-to-cell interactions required for pellicle formation. Continued expression of the motility complex in mature biofilms is unusual and suggests a role for the flagellar apparatus in the biofilm phenotype.


Assuntos
Proteínas de Bactérias/fisiologia , Biofilmes/crescimento & desenvolvimento , Campylobacter jejuni/fisiologia , Flagelos/fisiologia , Proteoma/fisiologia , Aderência Bacteriana , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas da Membrana Bacteriana Externa/fisiologia , Proteínas de Bactérias/análise , Proteínas de Bactérias/metabolismo , Campylobacter jejuni/metabolismo , Eletroforese em Gel Bidimensional , Flagelos/metabolismo , Flagelina/metabolismo , Movimento , Proteoma/metabolismo
9.
J Biol Chem ; 279(19): 20327-38, 2004 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-14985343

RESUMO

We examined two variants of the genome-sequenced strain, Campylobacter jejuni NCTC11168, which show marked differences in their virulence properties including colonization of poultry, invasion of Caco-2 cells, and motility. Transcript profiles obtained from whole genome DNA microarrays and proteome analyses demonstrated that these differences are reflected in late flagellar structural components and in virulence factors including those involved in flagellar glycosylation and cytolethal distending toxin production. We identified putative sigma(28) and sigma(54) promoters for many of the affected genes and found that greater differences in expression were observed for sigma(28)-controlled genes. Inactivation of the gene encoding sigma(28), fliA, resulted in an unexpected increase in transcripts with sigma(54) promoters, as well as decreased transcription of sigma(28)-regulated genes. This was unlike the transcription profile observed for the attenuated C. jejuni variant, suggesting that the reduced virulence of this organism was not entirely due to impaired function of sigma(28). However, inactivation of flhA, an important component of the flagellar export apparatus, resulted in expression patterns similar to that of the attenuated variant. These findings indicate that the flagellar regulatory system plays an important role in campylobacter pathogenesis and that flhA is a key element involved in the coordinate regulation of late flagellar genes and of virulence factors in C. jejuni.


Assuntos
Proteínas de Bactérias/genética , Campylobacter jejuni/genética , Proteínas de Ligação a DNA , Genoma Bacteriano , Proteínas de Membrana/genética , Animais , Proteínas de Bactérias/metabolismo , Células CACO-2 , Movimento Celular , Galinhas , DNA Complementar/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Eletroforese em Gel Bidimensional , Flagelos/metabolismo , Humanos , Microscopia Eletrônica , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas/química , RNA/metabolismo , RNA Polimerase Sigma 54 , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Fator sigma/metabolismo
10.
J Biol Chem ; 277(45): 42530-9, 2002 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-12186869

RESUMO

Mass spectrometry investigations of partially purified Campylobacter jejuni protein PEB3 showed it to be partially modified with an Asn-linked glycan with a mass of 1406 Da and composed of one hexose, five N-acetylhexosamines and a species of mass 228 Da, consistent with a trideoxydiacetamidohexose. By means of soybean lectin affinity chromatography, a mixture of glycoproteins was obtained from a glycine extract, and two-dimensional gel proteomics analysis led to the identification of at least 22 glycoproteins, predominantly annotated as periplasmic proteins. Glycopeptides were prepared from the glycoprotein mixture by Pronase digestion and gel filtration. The structure of the glycan was determined by using nano-NMR techniques to be GalNAc-alpha1,4-GalNAc-alpha1,4-[Glcbeta1,3-]GalNAc-alpha1,4-GalNAc-alpha1,4-GalNAc-alpha1,3-Bac-beta1,N-Asn-Xaa, where Bac is bacillosamine, 2,4-diacetamido-2,4,6-trideoxyglucopyranose. Protein glycosylation was abolished when the pglB gene was mutated, providing further evidence that the enzyme encoded by this gene is responsible for formation of the glycopeptide N-linkage. Comparison of the pgl locus with that of Neisseria meningitidis suggested that most of the homologous genes are probably involved in the biosynthesis of bacillosamine.


Assuntos
Campylobacter jejuni/química , Glicoproteínas/química , Polissacarídeos/química , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Sequência de Carboidratos , Glicopeptídeos/química , Glicopeptídeos/isolamento & purificação , Glicoproteínas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/química , Fragmentos de Peptídeos/química , Tripsina
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