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1.
Oxid Med Cell Longev ; 2018: 8936251, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30473743

RESUMO

Aging skeletal muscles are characterized by a progressive decline in muscle mass and muscular strength. Such muscular dysfunctions are usually associated with structural and functional alterations of skeletal muscle mitochondria. The senescence-accelerated mouse-prone 8 (SAMP8) model, characterized by premature aging and high degree of oxidative stress, was used to investigate whether a combined intervention with mild physical exercise and ubiquinol supplementation was able to improve mitochondrial function and preserve skeletal muscle health during aging. 5-month-old SAMP8 mice, in a presarcopenia phase, have been randomly divided into 4 groups (n = 10): untreated controls and mice treated for two months with either physical exercise (0.5 km/h, on a 5% inclination, for 30 min, 5/7 days per week), ubiquinol 10 (500 mg/kg/day), or a combination of exercise and ubiquinol. Two months of physical exercise significantly increased mitochondrial damage in the muscles of exercised mice when compared to controls. On the contrary, ubiquinol and physical exercise combination significantly improved the overall status of the skeletal muscle, preserving mitochondrial ultrastructure and limiting mitochondrial depolarization induced by physical exercise alone. Accordingly, combination treatment while promoting mitochondrial biogenesis lowered autophagy and caspase 3-dependent apoptosis. In conclusion, the present study shows that ubiquinol supplementation counteracts the deleterious effects of physical exercise-derived ROS improving mitochondrial functionality in an oxidative stress model, such as SAMP8 in the presarcopenia phase.


Assuntos
Doenças Mitocondriais/tratamento farmacológico , Doenças Mitocondriais/terapia , Ubiquinona/análogos & derivados , Animais , Autofagia/efeitos dos fármacos , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Citometria de Fluxo , Camundongos , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/metabolismo , Doenças Mitocondriais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal , Ubiquinona/farmacologia , Ubiquinona/uso terapêutico
2.
Biochim Biophys Acta ; 1838(3): 957-67, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24296066

RESUMO

Here we present a quantitative mechanism-based investigation aimed at comparing the cell uptake, intracellular trafficking, endosomal escape and final fate of lipoplexes and lipid-protamine/deoxyribonucleic acid (DNA) (LPD) nanoparticles (NPs) in living Chinese hamster ovary (CHO) cells. As a model, two lipid formulations were used for comparison. The first formulation is made of the cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and the zwitterionic lipid dioleoylphosphocholine (DOPC), while the second mixture is made of the cationic 3ß-[N-(N,N-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) and the zwitterionic helper lipid dioleoylphosphatidylethanolamine (DOPE). Our findings indicate that lipoplexes are efficiently taken up through fluid-phase macropinocytosis, while a less efficient uptake of LPD NPs occurs through a combination of both macropinocytosis and clathrin-dependent pathways. Inside the cell, both lipoplexes and LPD NPs are actively transported towards the cell nucleus, as quantitatively addressed by spatio-temporal image correlation spectroscopy (STICS). For each lipid formulation, LPD NPs escape from endosomes more efficiently than lipoplexes. When cells were treated with DOTAP-DOPC-containing systems the majority of the DNA was trapped in the lysosome compartment, suggesting that extensive lysosomal degradation was the rate-limiting factors in DOTAP-DOPC-mediated transfection. On the other side, escape from endosomes is large for DC-Chol-DOPE-containing systems most likely due to DOPE and cholesterol-like molecules, which are able to destabilize the endosomal membrane. The lipid-dependent and structure-dependent enhancement of transfection activity suggests that DNA is delivered to the nucleus synergistically: the process requires both the membrane-fusogenic activity of the nanocarrier envelope and the employment of lipid species with intrinsic endosomal rupture ability.


Assuntos
DNA/química , Técnicas de Transferência de Genes , Lipídeos/química , Nanocompostos/química , Nanoestruturas/química , Animais , Células CHO , Cátions/química , Cricetinae , Cricetulus , DNA/administração & dosagem , Endossomos/metabolismo , Citometria de Fluxo , Terapia Genética , Lipossomos/química , Pinocitose , Protaminas/metabolismo
3.
Mol Pharm ; 10(12): 4654-65, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24188138

RESUMO

We packaged condensed DNA/protamine particles in multicomponent envelope-type nanoparticle systems (MENS) combining different molar fractions of the cationic lipids 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 3ß-[N-(N,N-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) and the zwitterionic lipids dioleoylphosphocholine (DOPC) and dioleoylphosphatidylethanolamine (DOPE). Dynamic light scattering (DLS) and microelectrophoresis allowed us to identify the cationic lipid/DNA charge ratio at which MENS are small sized and positively charged, while synchrotron small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM) revealed that MENS are well-shaped DNA/protamine particles covered by a lipid monobilayer. Transfection efficiency (TE) experiments indicate that a nanoparticle formulation, termed MENS-3, was not cytotoxic and highly efficient to transfect Chinese hamster ovary (CHO) cells. To rationalize TE, we performed a quantitative investigation of cell uptake, intracellular trafficking, endosomal escape, and final fate by laser scanning confocal microscopy (LSCM). We found that fluid-phase macropinocytosis is the only endocytosis pathway used by MENS-3. Once taken up by the cell, complexes that are actively transported by microtubules frequently fuse with lysosomes, while purely diffusing systems do not. Indeed, spatiotemporal image correlation spectroscopy (STICS) clarified that MENS-3 mostly exploit diffusion to move in the cytosol of CHO cells, thus explaining the high TE levels observed. Also, MENS-3 exhibited a marked endosomal rupture ability resulting in extraordinary DNA release. The lipid-dependent and structure-dependent TE boost suggests that efficient transfection requires both the membrane-fusogenic activity of the nanocarrier envelope and the employment of lipid species with intrinsic endosomal rupture ability.


Assuntos
DNA/química , DNA/genética , Nanopartículas/química , Protaminas/química , Animais , Células CHO , Colesterol/análogos & derivados , Colesterol/química , Cricetulus , Endocitose/efeitos dos fármacos , Endossomos/metabolismo , Ácidos Graxos Monoinsaturados/química , Técnicas de Transferência de Genes , Lipídeos/química , Lipossomos/metabolismo , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Compostos de Amônio Quaternário/química , Transfecção/métodos
4.
Cancer Gene Ther ; 18(8): 543-52, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21394110

RESUMO

Multicomponent lipoplexes have recently emerged as especially promising transfection candidates, as they are from 10 to 100 times more efficient than binary complexes usually employed for gene delivery purposes. Previously, we investigated a number of chemical-physical properties of DNA-lipid complexes that were proposed to affect transfection efficiency (TE) of lipoplexes, such as nanoscale structure, size, surface potential, DNA-protection ability and DNA release from complexes upon interaction with cellular lipids. Although some minor differences between multicomponent and binary lipoplexes were found, they did not correlate clearly with efficiency. Instead, here we show that a marked difference between the cell internalization mechanism of binary and multicomponent lipoplexes does exist. Multicomponent lipoplexes significantly transfect cells at 4 °C, when endocytosis does not take place suggesting that they can enter cells via a temperature-independent mechanism. Confocal fluorescence microscopy experiments showed the existence of a correlation between endosomal escape and TE. Multicomponent lipoplexes exhibited a distinctive ability of endosomal escape and release DNA into the nucleus, whereas, poorly efficient binary lipoplexes exhibited minor, if any, endosomal rupture ability and remained confined in perinuclear late endosomes. Stopped-flow mixing measurements showed that the fusion rates of multicomponent cationic liposomes with anionic vesicles, used as model systems of cell membranes, were definitely shorter than those of binary liposomes. As either lipoplex uptake and endosomal escape involve fusion between lipoplex and cellular membranes, we suggest that a mechanism of lipoplex-cellular membrane interaction, driven by lipid mixing between cationic and anionic cellular lipids, does explain the TE boost of multicomponent lipoplexes.


Assuntos
Membrana Celular/química , Terapia Genética/métodos , Lipossomos/química , Animais , Células CHO , Linhagem Celular Tumoral , Membrana Celular/genética , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Humanos , Lipossomos/metabolismo , Microscopia Confocal , Transfecção
6.
Arq. bras. med. vet. zootec ; 61(2): 491-497, abr. 2009. graf, tab
Artigo em Português | LILACS | ID: lil-518727

RESUMO

Os efeitos da temperatura ambiente cíclica elevada sobre a morfometria da mucosa duodenal e o peso corporal em frangos de corte foram avaliados. Setenta pintos de corte, machos, foram alojados em gaiolas e distribuídos em dois grupos. Um grupo foi submetido diariamente, durante uma hora, à temperatura ambiente cíclica elevada do primeiro até o 42º dia de idade (ambiente ST); e outro foi mantido em conforto térmico (ambiente TN). Cinco frangos de cada grupo foram sacrificados, semanalmente, por deslocamento cervical para mensuração da altura de vilosidades (VI), profundidade das criptas (CR) e relação vilo/cripta (VI/CR) duodenal. Dez aves de cada grupo foram pesadas semanalmente em balança digital. Utilizou-se delineamento inteiramente ao acaso em esquema fatorial 7x2 (sete idades: um, sete, 14, 21, 28, 35 e 42 dias, e dois ambientes: ST e TN). Os ambientes foram comparados pelo teste de Fisher (P<0,05), e, para avaliar o efeito da idade, foi realizada análise de regressão polinomial. As aves do ambiente ST apresentaram menores VI aos 14 e 21 dias, menor CR aos 28 dias e menor VI/CR aos 21 dias de idade do que as aves do ambiente TN. A temperatura ambiente cíclica elevada teve efeito danoso sobre a estrutura da mucosa duodenal de frangos de corte até a quarta semana de idade e sobre o peso corporal ao final do ciclo produtivo.


The effects of high cyclic environment temperature on body weight and morphometry of the duodenal mucosa in broiler chicken were evaluated. Seventy one-day-old male broiler chicks were sheltered in cages and distributed in two groups. One group was daily exposed to high cyclic environment temperature for an hour, from hatching to 42 days of age (group ST), the other one was kept under thermoneutral conditions (group TN). Five chickens of each group were weekly slaughtered by cervical delocation to mesure the villosities height (VI), crypts depth (CR), and villo/crypt ratio (VI/ CR) in the duodenum. Ten chickens of each group were weighted weekly on a digital balance. A completely randomized experimental design in a 7x2 factorial arrangement (hatching, seven, 14, 21, 28, 35, and 42 days of age and two environments: ST and TN). The environments were compared by Fisher test (P<0.05) and the effects of days of life by polynomial regression. The ST group had reduction in VI at 14 and 21 days of age (P<0.01), CR at 28 days of age (P<0.05), and in VI/CR at 21 days of age (P<0.01). Cyclic high environment temperature had harmful effect on intestinal structure of broiler from hatching to four weeks of age and on body weigh at the end of the productive cycle.


Assuntos
Animais , Peso Corporal , Duodeno/anatomia & histologia , Transtornos de Estresse por Calor , Aves Domésticas
7.
Oncogene ; 27(18): 2542-51, 2008 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-17998939

RESUMO

Tumor microenvironment in carcinomas recruits mesenchymal cells with an abnormal proangiogenic and invasive phenotype. It is not clear whether mesenchymal tumor cells (MTCs) derive from the activation of mature fibroblasts or from their stem cell precursors. However, stromal cell activation in tumors resembles in several aspects the mesenchymal rearrangement which normally occurs during reparative processes such as wound healing. Mesenchymal stem cells (MSCs) play a crucial role in developmental and reparative processes and have extraordinary proangiogenic potential, on the basis of which they are thought to show great promise for the treatment of ischemic disorders. Here, we show that MTCs have proangiogenic potential and that they share the transcriptional expression of the best-known proangiogenic factors with MSCs. We also found that MTCs and MSCs have the same molecular signature for stemness-related genes, and that when co-implanted with cancer cells in syngeneic animals MSCs determine early tumor appearance, probably by favoring the angiogenic switch. Our data (1) reveal crucial aspects of the proangiogenic phenotype of MTCs, (2) strongly suggest their stem origin and (3) signal the risk of therapeutic use of MSCs in tumor-promoting conditions.


Assuntos
Proteínas Angiogênicas/biossíntese , Regulação Neoplásica da Expressão Gênica , Neoplasias Mamárias Animais/metabolismo , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Células-Tronco Mesenquimais/metabolismo , Neovascularização Patológica/metabolismo , Animais , Linhagem Celular Tumoral , Fibroblastos/metabolismo , Fibroblastos/patologia , Isquemia/metabolismo , Isquemia/patologia , Isquemia/terapia , Neoplasias Mamárias Animais/patologia , Células-Tronco Mesenquimais/patologia , Camundongos , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/patologia , Ratos , Células Estromais/metabolismo , Células Estromais/patologia , Transcrição Gênica , Transplante Isogênico
8.
Int J Immunopathol Pharmacol ; 21(4): 867-77, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19144272

RESUMO

T cells from HLA-A2+ healthy donors were co-cultured with autologous dendritic cells (DC) loaded with apoptotic tumor cells expressing rat neu, and were induced to mature by tumor necrosis factor (TNF)alpha and interleukin (IL)-1beta (mDC(neu)) or by the CCL16 chemokine (CCL16/mDC(neu)). Priming by CCL16/mDC(neu) induces a larger population of T cells that express cytoplasmatic interferon (IFN)gamma, TNFalpha, perforin and granzyme B compared to those primed by mDC(neu). T cells primed by CCL16/mDC(neu) release IFNgamma in response to human HER-2+ cells and kill human HER-2+ target cells more efficiently than those primed by mDC(neu). Our results show that both the loading of DC with xenogeneic rat neu and their maturation by CCL16 are two issues of critical importance for the elicitation of an effective response to human HER-2 in T cells from normal donors.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Quimiocinas CC/fisiologia , Receptor ErbB-2/imunologia , Animais , Linhagem Celular , Técnicas de Cocultura , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Ratos
9.
Neurol Sci ; 28(5): 279-81, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17972044

RESUMO

An unusual case of brachial plexopathy following an alcohol binge is presented. The patient developed numbness and weakness of his right hand and neurophysiological tests demonstrated that the lesion level was at the brachial plexus. MRI of the brachial plexus, cerebrospinal fluid examination and DNA analysis for hereditary neuropathy with liability to pressure palsies were normal. Repeated neurological examination and neurophysiological studies 60 days later were normal. A diagnosis of brachial plexus neuropathy consequent to non-traumatic stretching of the middle and the lower trunks was made.


Assuntos
Neuropatias do Plexo Braquial/fisiopatologia , Plexo Braquial/fisiopatologia , Paresia/fisiopatologia , Adulto , Neuropatias do Plexo Braquial/patologia , Humanos , Masculino , Condução Nervosa/fisiologia , Paresia/patologia
10.
Clin Ter ; 158(2): 115-20, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-17566511

RESUMO

OBJECTIVE: To contribute to an early diagnosis of pulmonary involvement in scleroderma by evaluating the correlation between respiratory symptoms and functional respiratory data observed. PATIENTS AND METHODS: 86 patients affected by scleroderma, 76 women and 10 men, age 14-75, underwent lung function tests, blood gas sample, CO diffusing capacity in setting and supine position, respiratory drive measurement through P0.1 and evaluation of the respiratory muscles efficiency with Maximum Inspiratory Pressure (MIP). RESULTS: Data obtained suggested us to divide our patients in four different groups: first group where both spirometric data and pulmonary diffusion were normal; a second group with a clear reduction of pulmonary diffusion likely due to the reduction of vascular bed; a third group where we observed a restrictive ventilatory impairment due to the reduction of the compliance and a reduction of the pulmonary diffusion likely related to interstitial damage; finally, a fourth group where beside a restricted spirometric outline we have detected a more accentuated reduction of pulmonary diffusion likely due to pulmonary hypertension. Moreover, our study has highlighted a progressive decrease of MIP and Maximum Voluntary Ventilation (MVV) shifting from the first to the fourth group, suggesting reduction of the muscular efficiency with an increase of P0.1 index of activity in the respiratory drive. CONCLUSIONS: The results could explain the dyspnea often reported by the patients affected by scleroderma even without spirometric alteration.


Assuntos
Escleroderma Sistêmico/fisiopatologia , Adolescente , Adulto , Idoso , Análise Química do Sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escleroderma Sistêmico/sangue , Espirometria
11.
Neurol Sci ; 27(6): 442-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17205233

RESUMO

Post-malaria neurological syndrome (PMNS) is a rare complication of malaria. It follows recovery from an episode of Plasmodium falciparum malaria and is characterised by symptoms and signs of encephalopathy. Patients usually improve without any specific treatment. The pathogenesis is unknown, but it is probably immunologically mediated. The objective of this case study is to describe the first Italian patient with PMNS. A 60-year-old Italian man developed acute P. falciparum malaria after a stay in French Guinea. Twenty days after recovering from malaria, he became confused, developed generalised weakness, limb tremors, shivering and dizziness. These symptoms continued for three days, then resolved spontaneously. Neuroimaging was normal. Cerebrospinal fluid analysis revealed breakdown of the blood/brain barrier, without oligoclonal bands and normal IgG index. Our patient presented a mild diffuse encephalopathy suggestive of a generic activation of the immune system without any specific reaction against antigens within the CNS.


Assuntos
Ataxia Cerebelar/etiologia , Malária Falciparum/complicações , Doenças do Sistema Nervoso/etiologia , Plasmodium falciparum/isolamento & purificação , Animais , Ataxia Cerebelar/diagnóstico , Ataxia Cerebelar/imunologia , Humanos , Imunoglobulina G/sangue , Malária Falciparum/diagnóstico , Malária Falciparum/imunologia , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/imunologia
13.
Neurosci Lett ; 381(1-2): 86-91, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15882795

RESUMO

Nitric oxide and prostaglandins are among the numerous substances released by activated glial cells. The aim of this study was to evaluate the effect of high-level aspirin on iNOS expression in cultured rat glial cells treated with lipopolysaccharide (LPS) as pathological stimulator. Using Western Blotting, we verified that aspirin enhanced LPS-induced iNOS expression and the presence of 15-deoxy-Delta(12,14)-prostaglandin (15d-PGJ2) suppressed this aspirin effect. However, the exposure of LPS-treated glial cells to aspirin resulted in a decrease of NO production. These results suggest that aspirin interferes with the cross-talk of prostaglandins and NO, blocking the endogenous negative control exerted by COX products on iNOS expression. On the other side, aspirin seems to act directly on iNOS reducing its activity, even if it does not completely block NO release by LPS-stimulated glial cells. Then aspirin could maintain homeostatic functions of NO, while it prevents toxic effects, corresponding to high NO concentrations.


Assuntos
Aspirina/administração & dosagem , Lipopolissacarídeos/administração & dosagem , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico/metabolismo , Prostaglandina D2/análogos & derivados , Prostaglandina D2/administração & dosagem , Animais , Animais Recém-Nascidos , Células Cultivadas , Relação Dose-Resposta a Droga , Interações Medicamentosas , Óxido Nítrico Sintase Tipo II , Ratos , Ratos Wistar
14.
Comp Immunol Microbiol Infect Dis ; 27(3): 171-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15001312

RESUMO

A bovine herpesvirus-1 (BHV-1) vaccine expressing glycoprotein D, the form with the transmembrane anchor removed, was evaluated for inducing immunity in calves. The plasmid encoding gD of BHV-1 was injected three times to nine calves, using three animals for each of the following routes: intramuscularly (i.m.), intradermally (i.d.), or intranasally (i.n.). Three additional calves were given the plasmid vector only and served as unvaccinated controls. When calves were subjected to challenge infection with BHV-1, all vaccinated calves as well as the controls developed a typical severe form of infectious bovine rhinotracheitis. However, compared to the controls, the vaccinated calves showed earlier clearance of challenge virus. Moreover, the calves given the vaccine i.m. developed neutralizing antibody to BHV-1 between 21 and 42 days following the first injection of vaccine, whereas in calves vaccinated either i.d. or i.n., as well as the controls, antibody first appeared in their sera 14 days post-challenge infection.


Assuntos
Doenças dos Bovinos/virologia , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/imunologia , Imunização/veterinária , Vacinas de DNA/administração & dosagem , Proteínas Virais/imunologia , Vacinas Virais/administração & dosagem , Animais , Anticorpos Antivirais/sangue , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/prevenção & controle , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/prevenção & controle , Infecções por Herpesviridae/virologia , Testes de Neutralização/veterinária , Vacinas de DNA/efeitos adversos , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Proteínas Virais/genética , Vacinas Virais/efeitos adversos , Vacinas Virais/genética , Vacinas Virais/imunologia
15.
Mech Ageing Dev ; 123(1): 47-57, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11640951

RESUMO

Reactive glial cell properties could contribute to pathomechanisms underlying Alzheimer's disease by favoring oxidative neuronal damage and beta-amyloid toxicity. A critical step is apparently reached when pathological glia activation is no longer restricted to microglia and includes astrocytes. By giving up their differentiated state, astrocytes may lose their physiological negative feed-back control on microglial NO production and even contribute to neurotoxic peroxynitrate formation. Another consequence is the impairment of the astrocyte-maintained extracellular ion homeostasis favoring excitotoxic damage. By the production of apolipoprotein-E, triggered by the microglial cytokine interleukine-1beta, reactive astrocytes could promote the transformation of beta-amyloid into the toxic form. A pharmacologically reinforced cAMP signaling in rat glial cell cultures depressed oxygen radical formation in microglia and their release of TNF-alpha and interleukine-1beta, feed-forward signals which mediate oxidative damage and secondary astrocyte activation. Cyclic AMP also favored differentiation and expression of a mature ion channel pattern in astrocytes improving their glutamate buffering. A deficient cholinergic signaling that increases the risk of pathological APP processing was compensated by an adenosine-mediated reinforcement of the second messenger calcium. A combination therapy with acetylcholine-esterase inhibitors together with adenosine raising pharmaca, therefore, may be used to treat cholinergic deficiency in Alzheimer's disease.


Assuntos
Doença de Alzheimer/patologia , Astrócitos/patologia , AMP Cíclico/metabolismo , Microglia/patologia , Transdução de Sinais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Astrócitos/metabolismo , Humanos , Microglia/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia
16.
Acta Neurol Scand ; 104(2): 110-2, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11493229

RESUMO

OBJECTIVES: To evaluate the efficacy of gabapentin in the treatment of hemifacial spasm. MATERIAL AND METHODS: Twenty-three patients with hemifacial spasm not suitable for surgery or therapy with botulinum toxin were treated with gabapentin. The main efficacy parameter was the percentage of spasm reduction. RESULTS: A clinically significant reduction of spasms was obtained by 16 patients. CONCLUSION: Gabapentin was effective and safe in reducing hemifacial spasm in 16 out 23 (69.6%) patients.


Assuntos
Acetatos/uso terapêutico , Aminas , Anticonvulsivantes/uso terapêutico , Ácidos Cicloexanocarboxílicos , Espasmo Hemifacial/tratamento farmacológico , Ácido gama-Aminobutírico , Adulto , Idoso , Feminino , Gabapentina , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento
17.
Int J Biol Macromol ; 28(4): 321-30, 2001 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-11311722

RESUMO

The structure--function relationships occurring on the bovine thymus 20S proteasome, which exhibits the features of an immunoproteasome, have been studied. The investigation has been performed, essentially, using a fluorimetric approach, taking advantage either of the sensitivity of the complex to sodium dodecil sulfate and chaotropic agents (urea and guanidine hydrochloride) or of the presence, on the molecule, of a high number of tryptophan residues. The results obtained indicate that the perturbation or the oxidation of these residues affect the catalytic events taking place on the thymus proteasome and that the functional effects determined by SDS and chaotropic agents most likely occur through a series of progressive structural modifications leading to an inactive molecule. The presence of structural intermediates in the proteasome inactivation process suggests that thymus proteasome is a molecule characterized, at the same time, by structural flexibility (modulation of active sites) and structural stability (maintaining of the quaternary structure) in agreement with its crucial role in the cell life cycle.


Assuntos
Cisteína Endopeptidases/metabolismo , Complexos Multienzimáticos/metabolismo , Animais , Bovinos , Cisteína Endopeptidases/química , Fluorescência , Fluorometria/métodos , Guanidina , Complexos Multienzimáticos/química , Complexo de Endopeptidases do Proteassoma , Desnaturação Proteica , Dodecilsulfato de Sódio , Relação Estrutura-Atividade , Timo/enzimologia , Ureia
19.
Neuromuscul Disord ; 10(6): 391-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10899444

RESUMO

Spinal and bulbar muscular atrophy (Kennedy disease) is an adult form of X-linked motor neuron disease caused by the expansion of a polymorphic CAG-repeat sequence in the first exon of the androgen receptor gene. We studied clinical and molecular features of 36 patients and 19 heterozygous females. Phenotypic manifestations and disease severity broadly varied among our spinal and bulbar muscular atrophy patients. The size of CAG expansion significantly influences the age of disease onset, but neither clinical features nor disease severity. The majority of carrier women presented signs of chronic denervation at neurophysiological examination and, in three cases, low-amplitude sensory action potentials were recorded. Notably, a few women developed mild signs of bulbar motor neuron impairment later in life. The identification of a large number of patients by the use of the molecular test further supports the hypothesis that Kennedy disease had been previously underdiagnosed, probably because of the great variability of clinical presentation. Although an early diagnosis may not be crucial for treatment, given the lack of effective therapy, the molecular testing can be of great relevance for disease prognosis and genetic counseling.


Assuntos
Heterozigoto , Atrofia Muscular Espinal/genética , Receptores Androgênicos/genética , Expansão das Repetições de Trinucleotídeos/genética , Potenciais de Ação , Adulto , Idade de Início , Idoso , Alelos , Creatina Quinase/sangue , Fasciculação , Feminino , Triagem de Portadores Genéticos , Hormônios Esteroides Gonadais/sangue , Gonadotropinas Hipofisárias/sangue , Ginecomastia , Humanos , Hipestesia , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Debilidade Muscular , Atrofia Muscular Espinal/sangue , Atrofia Muscular Espinal/epidemiologia , Penetrância , Fenótipo , Análise de Sequência de DNA
20.
Ann N Y Acad Sci ; 903: 24-33, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10818485

RESUMO

A pathological glia activation, stimulated by inflammatory proteins, beta-amyloid, or brain ischemia, is discussed as a common pathogenic factor for progressive nerve cell damage in vascular and Alzheimer dementia. A critical point seems to be reached, if the cytokine-controlled microglial upregulation causes a secondary activation of astrocytes which loose the negative feedback control, are forced to give up their physiological buffering function, and may add to neuronal damage by the release of nitric oxide (NO) and by promoting toxic beta-amyloid formation. A strengthening of the cyclic adenosine-5',3'-monophosphate (cAMP) signaling exerted a differential inhibition of the stimulatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) released from cultured rat microglia, but maintained the negative feedback signal IL-6; cAMP inhibited also the release of free oxygen radicals (OR) but not of NO. Reinforcement of the NO-induced cyclic guanosine monophosphate (cGMP) increase by blockade of the phosphodiesterase (PDE) subtype-5 with propentofylline counterbalanced the toxic NO action that causes with OR neuronal damage by peroxynitrate formation. In rat cultured astrocytes, a prolonged cAMP elevation favored cell differentiation, the expression of a mature ion channel patter, and an improvement of the extracellular glutamate uptake. Cyclic AMP signaling could be strengthened by PDE blockade and by raising extracellular adenosine, which stimulates A2 receptor-mediated cAMP synthesis. Via an A1 receptor-mediated effect, elevated adenosine was found to overcome a deficient intracellular calcium mobilization resulting from an impaired muscarinic signaling at pathologically decreased acetylcholine concentrations. We suggest that pharmaca, which elevate extracellular adenosine and/or block the degradation of cyclic nucleotides, may be used to counteract glia-related neuronal damage in dementing processes.


Assuntos
Doença de Alzheimer/fisiopatologia , AMP Cíclico/fisiologia , GMP Cíclico/fisiologia , Demência Vascular/fisiopatologia , Microglia/fisiologia , Neuroglia/fisiologia , Peptídeos beta-Amiloides/fisiologia , Animais , Astrócitos/fisiologia , Humanos , Inflamação , Modelos Neurológicos , Ratos , Transdução de Sinais
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