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1.
Rev Neurol (Paris) ; 179(9): 1020-1029, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37735015

RESUMO

Relationships between genes and amyotrophic lateral sclerosis (ALS) have been widely accepted since the first studies highlighting pathogenic mutations in the SOD1 gene 30years ago. Over the last three decades, scientific literature has clearly highlighted the central role played by genetic factors in the disease, in both clinics and pathophysiology, as well as in therapeutics. This implies that health professionals who care for patients with ALS are increasingly faced with patients and relatives eager to have answers to questions related to the role of genetic factors in the occurrence of the disease and the risk for their relatives to develop ALS. In order to address these public health issues, the French ALS network FILSLAN proposed to the Haute Autorité de santé (HAS) the drafting of a French National Protocol (PNDS) on ALS genetics. This PNDS was developed according to the "method for developing a national diagnosis and care protocol for rare diseases" published by the HAS in 2012 (methodological guide for PNDS available on the HAS website: http://www.has-sante.fr/). This document aims to provide the most recent data on the role of genes in ALS and to detail the implications for diagnosis and care.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/genética , Mutação
2.
Rev Neurol (Paris) ; 173(5): 288-299, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28461024

RESUMO

Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive and fatal neurodegenerative disease characterized by progressive weakness of voluntary muscles of movement as well as those for swallowing, speech and respiration. In the absence of curative treatment, care can improve quality of life, prolong survival, and support ALS patients and their families, and also help them to anticipate and prepare for the end of life. Multidisciplinary management in tertiary centers is recommended in close collaboration with general practitioners, home carers and a dedicated health network. Patients' follow-up deals mainly with motor impairment and physical disability, adaptation, nutrition and respiratory function. Involvement of palliative care as part of the multidisciplinary team management offers patients the possibility of discussing their end of life issues. This review summarizes the different aspects of ALS care, from delivering the diagnosis to the end of life, and the organization of its management.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Administração dos Cuidados ao Paciente , Esclerose Lateral Amiotrófica/fisiopatologia , Esclerose Lateral Amiotrófica/psicologia , Esclerose Lateral Amiotrófica/reabilitação , Humanos , Apoio Nutricional , Cuidados Paliativos , Equipe de Assistência ao Paciente , Respiração Artificial
3.
Rev Neurol (Paris) ; 170(2): 134-9, 2014 Feb.
Artigo em Francês | MEDLINE | ID: mdl-24239347

RESUMO

INTRODUCTION: Diagnosis of bulbar ALS is difficult at the early stage of the disease. According to guidelines, early diagnosis is better in view to optimize the management of affected patients. To improve the sensitivity without losing specificity of the prior criteria, the Board of Awaji has proposed modified electrodiagnostic criteria for ALS. The aim of this study was to evaluate the contribution of needle electromyography in early diagnosis of bulbar ALS by comparing the El Escorial criteria (EEC), Revised El Escorial Criteria (R-EEC) and Awaji algorithm (AA). METHODS: In a retrospective study, we analysed clinical and electrophysiological data of 46 patients followed in our center for a bulbar-onset ALS seen for the first time between January 2007 and February 2011. All these patients had bulbar-onset ALS probable or certain at the last follow-up. All data were collected during the first clinical examination and the first electrophysiological study. RESULTS: Mean age of the population was 69 (37-90years, sex ratio: 0.91). Using the EEC, 9 patients were diagnosed as definite or probable ALS at the first consultation. Applying the R-EEC, 13 patients were diagnosed as definite or probable ALS and using the AA, 23 patients were diagnosed as definite or probable ALS. The sensitivity of the EEC was 19.5%, the R-EEC was 28.2% and for AA was 49.98%. CONCLUSION: AA are more sensitive in early diagnosis of bulbar ALS compared to R-EEC with the contribution of ENMG and when fasciculations are considered as evidence of spontaneous activity. Such an approach can contribute to accelerate an optimal management of the disease. AA are a breakthrough in the diagnosis of ALS especially in the bulbar-onset forms.


Assuntos
Algoritmos , Esclerose Lateral Amiotrófica/diagnóstico , Técnicas de Diagnóstico Neurológico , Eletromiografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Precoce , Fasciculação/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos
4.
Rev Neurol (Paris) ; 169(6-7): 485-9, 2013.
Artigo em Francês | MEDLINE | ID: mdl-23398961

RESUMO

Should a patient be forced to accept a treatment, especially when suffering from a neurodegenerative disease? We argue that physicians, nurses and care givers should instead accept his or her choice in accordance with the principle that every patient is an autonomous person able to make a choice, even in case of declined cognition. Beside the legal obligation, we suggest a theoretical approach and focus on the practical impacts of the patient's decision. Our objective is to promote the value of ethical doubt and attentive listening to individual opinions, so as to improve the quality of the medical staff's work and reduce patients' distress when affected by fatal diseases.


Assuntos
Tomada de Decisões/fisiologia , Doenças Neurodegenerativas/terapia , Papel do Médico , Relações Médico-Paciente , Psicologia Clínica , Comportamento de Escolha/fisiologia , Humanos , Competência Mental , Autonomia Pessoal , Recursos Humanos
5.
Biomol NMR Assign ; 5(2): 135-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21188561

RESUMO

GNA1946 (Genome-derived Neisseria Antigen 1946) is a highly conserved exposed outer membrane lipoprotein from Neisseria meningitidis bacteria of 287 amino acid length (31 kDa). Although the structure of NMB1946 has been solved recently by X-Ray crystallography, understanding the behaviour of GNA1946 in aqueuos solution is highly relevant for the discovery of the antigenic determinants of the protein that will possibly lead to a more efficient vaccine development against virulent serogroup B strain of N. meningitidis. Here we report almost complete (1)H, (13)C and (15)N resonance assignments of GNA1946 (residues 10-287) in aqueous buffer solution.


Assuntos
Antígenos de Bactérias/química , Proteínas da Membrana Bacteriana Externa/química , Lipoproteínas/química , Neisseria meningitidis , Sequência de Aminoácidos , Isótopos de Carbono , Dados de Sequência Molecular , Isótopos de Nitrogênio , Proteínas Recombinantes/química , Alinhamento de Sequência
6.
Rev Neurol (Paris) ; 166(8-9): 683-98, 2010.
Artigo em Francês | MEDLINE | ID: mdl-20472259

RESUMO

This paper, written by French amyotrophic lateral sclerosis (ALS) center experts, presents an update of recent advances in fundamental, epidemiological and clinical research in ALS based on a review of the literature between September 2008 and November 2009. Among other pathophysiological mechanisms, the role of stress of the endoplasmic reticulum and the importance of energetic metabolic disturbances have been underscored. In the field of genetics, research has been advanced through the identification of mutations of the gene FUsed in Sarcoma/Translated in LipoSarcoma (FUS/TLS) in individuals with familial and sporadic ALS. This gene is involved in the regulation of transcription, splicing and RNA transport, and has functional homology to another ALS gene, TARDBP, which suggests that a common mechanism may underlie motor neuron degeneration. A report showed that mice expressing a mutant form of human TDP-43 develop a progressive and fatal neurodegenerative disease reminiscent of both ALS and frontotemporal lobar degeneration with ubiquitin aggregates (FTLD-U), providing a new animal model that may help to better understand the pathophysiology and test new therapeutics. Beside genetic studies, several epidemiologic studies have investigated the role of environmental factors. A recent study suggests that smoking is a risk factor for developing ALS and it is hypothesized that this could occur through lipid peroxidation via formaldehyde exposure. From a neuroprotective perspective, trials with IGF-1, sodium valproate, coenzyme Q or glatiramer acetate have failed to demonstrate any beneficial effect. A study published in 2008 argued that lithium may have a neuroprotective effect in ALS mice and also in patients. However, two preclinical studies failed to replicate the neuroprotective effect of lithium in ALS mice. Therapeutic trials have been performed or are currently ongoing in Europe and North America. Their results have not yet been published.


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/fisiopatologia , Esclerose Lateral Amiotrófica/psicologia , Animais , Biomarcadores , Ensaios Clínicos como Assunto , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Exposição Ambiental , Humanos , Desnutrição/etiologia , Desnutrição/terapia , Camundongos , Camundongos Transgênicos , Músculo Esquelético/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Proteína FUS de Ligação a RNA/deficiência , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/fisiologia , Fatores de Risco , Superóxido Dismutase/deficiência , Superóxido Dismutase/genética , Superóxido Dismutase/fisiologia , Superóxido Dismutase-1
7.
Rev Neurol (Paris) ; 165(8-9): 627-40, 2009.
Artigo em Francês | MEDLINE | ID: mdl-19524991

RESUMO

Amyotrophic lateral sclerosis (ALS) is the most common motor neuron disease. Loss of pyramidal and anterior horn motor neurons leads to progressive limb weakness, disability, dysarthria, dysphagia and respiratory insufficiency with a progressive fatal course. The incidence of ALS ranges between 1.5 to 2.5 for 100,000 per year. Although there are familial cases of ALS, about 90% are sporadic and of unknown etiology. Several exogenous risk factors have been documented. However, no convincing evidence has demonstrated in a reproducible manner an association between an environmental or lifestyle risk factor and ALS. Disease duration varies considerably, ranging from a few months to 10-15 years with a mean survival of about 36 months. Prognostic factors such as age, site of disease onset, nutritional, functional and respiratory status at the diagnosis or delay between beginning of the disease and diagnosis have been reported but they appear to be insufficient to explain prognostic variability. These last 15 years, development of supportive care for ALS patients and management in ALS centers may have contributed to improve survival. Finally, ALS centres, and particularly French ALS centres, have developed databases to improve our knowledge of ALS, phenotypic characterization, more accurate phenotype-genotype correlations and thus contribute to new therapeutics developments.


Assuntos
Esclerose Lateral Amiotrófica/epidemiologia , Adulto , Fatores Etários , Idoso , Esclerose Lateral Amiotrófica/diagnóstico , Estudos de Coortes , Meio Ambiente , Exposição Ambiental , Comportamento Alimentar , Feminino , França/epidemiologia , Geografia , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Exposição Ocupacional , Prognóstico , Sistema de Registros , Fatores de Risco , Fatores Sexuais , Esportes , Análise de Sobrevida
9.
Rev Neurol (Paris) ; 163(3): 335-40, 2007 Mar.
Artigo em Francês | MEDLINE | ID: mdl-17404520

RESUMO

INTRODUCTION: Mills' syndrome is a rare motor neuron disease, initially described by Mills in 1900 as a progressive ascending or descending hemiplegia without significant sensory involvement. This syndrome is of uncertain nosological status, and is supposedly due to unilateral primary degeneration of corticospinal pathway. Some authors have suggested that it could represent a variant of primary lateral sclerosis. METHODS: We retrospectively studied the clinical and paraclinical data from eight patients with suspected Mills' syndrome hospitalized for diagnosis. RESULTS: For all patients, the clinical course was slowly progressive, with motor deficiency, unilateral pyramidal signs (or bilateral with asymmetry), without bulbar signs, fasciculations or sensory deficit. Final diagnosis was Mills' syndrome (n=3), primary lateral sclerosis (n=1), myelitis of unknown origin (n=2), progressive primary multiple sclerosis (n=1), and antiphospholipid syndrome (n=1). The main arguments for final diagnosis were brought by electrophysiology and brain and spinal MRI. CONCLUSION: Mills' syndrome is a rare clinical diagnosis, requiring exhaustive investigations.


Assuntos
Encefalopatias/patologia , Doença dos Neurônios Motores/fisiopatologia , Idoso , Encéfalo/patologia , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/diagnóstico , Síndrome
10.
Rev Neurol (Paris) ; 162 Spec No 2: 4S104-4S107, 2006 Jun.
Artigo em Francês | MEDLINE | ID: mdl-17128096

RESUMO

To face the traumatic shock after the announcement of a severe and fatal disease, patients build psychological defences that physician must identify and respect as long as they don't endanger the patient's psychological fate and his medical care. ALS patient's do not have any curative perspective thus they will try "to escape" using different strategies the traumatic reality, that they cannot integrate and control. The physician has to prove his understanding and empathy facing these psychological reactions that could become of pathological appearance. The physician has to progressively bring the patient to consult the clinical psychologist; however he has not to forget that he is equally responsible about the way the patient go though his disease.


Assuntos
Esclerose Lateral Amiotrófica/psicologia , Revelação da Verdade , Humanos
11.
Rev Neurol (Paris) ; 162 Spec No 2: 4S244-4S252, 2006 Jun.
Artigo em Francês | MEDLINE | ID: mdl-17128118

RESUMO

In individuals with ALS rehabilitation is mainly designed to prevent fatigue and contracture, to improve independence and activities for as long as possible, to optimize ability to live with the handicap, and finally to maximize quality of life. The functional impairment must be defined and physical therapy techniques have to be adapted to each patient and reevaluated frequently during the course of the disease. Various types of massage and exercise, monitored by a physical therapist are effective. Strengthening or endurance exercises are controversial as exercise may injure muscle fibres and motor neurons. Isometric exercise, short of fatigue, of unaffected muscles is recommended. Range of motion exercise is critically important for preventing contraction. Assistive and adaptative equipments are essential for maintaining the patient's activities of daily living and home equipment preserves independence. Several orthoses for hand, arm, foot or cervical weakness are available. A wheelchair is an important adaptative device when walking becomes too fatiguing or impossible. Choice for special options and features may require attention. Pulmonary complications are prevented with adapted techniques for bronchic obstruction. Based on the degree of weakness of limb and axial muscles six stages of functional impairment can be defined ranging from fully ambulatory in stage I to bedridden and totally dependent in stage VI. This staging provides a framework for physical therapy evaluation and guidance for appropriate rehabilitation in ALS patients.


Assuntos
Esclerose Lateral Amiotrófica/reabilitação , Modalidades de Fisioterapia , Obstrução das Vias Respiratórias/prevenção & controle , Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/fisiopatologia , Humanos
12.
Rev Neurol (Paris) ; 160(6-7): 659-65, 2004 Jul.
Artigo em Francês | MEDLINE | ID: mdl-15247854

RESUMO

INTRODUCTION: Cyclophospamide is used in the treatment of progressive multiple sclerosis. We were looking for predictive indicators of treatment response. MATERIAL AND METHODS: Forty-seven patients with secondary progressive multiple sclerosis and seven others with primary progressive received monthly infusions of cyclophosphamide (750mg/m2) and methylprednisolone (500mg). During the year before cyclophosphamide the EDSS had worsened one point in all patients with or without surimposed relapses. Evaluation was based on EDSS change at 6, 12, 24 months and 5 years. RESULTS: Among secondary progressive patients, 91 per 100 (43/47) were stable or improved at 12 months, 65 per 100 (26/40) at 24 months and 22 per 100 (5/23) at 5 years. Annual relapse rate decreased from 0.81 before treatment to 0.48 during treatment and 0.12 after treatment (p<0.001). At 24 months, efficacy was correlated to a progressive phase lasting less than 5 years (p<0.01) and to a rapid increase of EDSS of at least 2 points the year before treatment (p<0.05). There were no influences of age, EDSS and surimposed relapses at the beginning of treatment, and other immunoactive drugs administrated before cyclophosphamide. There was no significant difference in quality of response to treatment between patients with primary progressive and secondary progressive multiple sclerosis. CONCLUSION: Cyclophosphamide appears to be more efficient in early stage of progressive multiple sclerosis independently of age, relapses or neurological disability scale.


Assuntos
Ciclofosfamida/uso terapêutico , Imunossupressores/uso terapêutico , Metilprednisolona/uso terapêutico , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Adjuvantes Imunológicos/uso terapêutico , Adulto , Azatioprina/uso terapêutico , Encéfalo/patologia , Ciclofosfamida/administração & dosagem , Demografia , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/administração & dosagem , Interferon beta/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/administração & dosagem , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/patologia , Estudos Prospectivos , Pulsoterapia/métodos , Recidiva , Estudos Retrospectivos
13.
Rev Med Interne ; 25(6): 464-7, 2004 Jun.
Artigo em Francês | MEDLINE | ID: mdl-15158318

RESUMO

INTRODUCTION: Duchenne and Becker muscular dystrophy are X-linked and affect mainly males. The authors report four female cases. EXEGESIS: Four patients presented muscular deficiency predominant to lower limbs and chronic disease. Female distrophinopathy is understandable by three mechanisms: Turner's syndrome, translocation X-chromosome with an autosome and skewed X-chromosome inactivation. CONCLUSION: Diagnosis of female Duchenne and Becker muscular dystrophy is really difficult if there is not male case in family.


Assuntos
Distrofia Muscular de Duchenne/diagnóstico , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade
14.
J Chemother ; 16 Suppl 5: 79-81, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15675486

RESUMO

The aim of this study was to investigate the role of magnetic resonance imaging (MRI) in the evaluation of response to radiofrequency ablation (RFA) and detect residual or recurrent tumor. After RFA, the target lesion shows a hyperintensive signal without increased T1-weighted, low on T2-weighted, non enhancing in gadolinium-enhanced MRI. In the long term follow-up the successfully treated lesions decrease in size. Signs of recurrence include new enhancement areas, the lesion's size increase, and development of T1-weighted hypointense and T2 weighted hyperintense areas. The MRI is a reliable method to evaluate the effectiveness of RFA and detect residual tumor.


Assuntos
Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Humanos , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética
15.
Infect Immun ; 69(8): 4923-30, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11447169

RESUMO

Heat-labile enterotoxin from enterotoxinogenic Escherichia coli is not only an important cause of diarrhea in humans and domestic animals but also possesses potent immunomodulatory properties. Recently, the nontoxic, receptor-binding B subunit of heat-labile enterotoxin (EtxB) was found to induce the selective death of CD8(+) T cells, suggesting that EtxB may trigger activation of proapoptotic signaling pathways. Here we show that EtxB treatment of CD8(+) T cells but not of CD4(+) T cells triggers the specific up-regulation of the transcription factor c-myc, implicated in the control of cell proliferation, differentiation, and death. A concomitant elevation in Myc protein levels was also evident, with peak expression occurring 4 h posttreatment. Preincubation with c-myc antisense oligodeoxynucleotides demonstrated that Myc expression was necessary for EtxB-mediated apoptosis. Myc activation was also associated with an increase of IkappaBalpha turnover, suggesting that elevated Myc expression may be dependent on NF-kappaB. When CD8(+) T cells were pretreated with inhibitors of IkappaBalpha turnover and NF-kappaB translocation, this resulted in a marked reduction in both EtxB-induced apoptosis and Myc expression. Further, a non-receptor-binding mutant of EtxB, EtxB(G33D), was shown to lack the capacity to activate Myc transcription. These findings provide further evidence that EtxB is a signaling molecule that triggers activation of transcription factors involved in cell survival.


Assuntos
Apoptose , Toxinas Bacterianas/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Enterotoxinas/farmacologia , Proteínas de Escherichia coli , Proteínas I-kappa B , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Escherichia coli , Camundongos , Camundongos Endogâmicos BALB C , Inibidor de NF-kappaB alfa , Oligodesoxirribonucleotídeos Antissenso , Inibidores da Síntese de Proteínas/farmacologia , Proteínas Proto-Oncogênicas c-myc/biossíntese , Proteínas Recombinantes/farmacologia , Tosilfenilalanil Clorometil Cetona/farmacologia , Ativação Transcricional
16.
Trends Microbiol ; 9(6): 262-6, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11390240

RESUMO

Haemolytic uraemic syndrome (HUS), which is caused by Shiga toxin (Stx)-producing Escherichia coli, is the commonest cause of acute renal failure in childhood. It is widely believed that HUS develops following the release of Stx, an AB5 toxin that inhibits protein synthesis and has a direct toxic effect on the kidney endothelium. There remains, however, a mismatch between the current understanding of the pathogenesis of HUS and the evolution of the clinical signs of the disease. Our hypothesis is that Stx-mediated immune cell activation in the gut is the missing link in the pathogenesis of this condition, initiating the characteristic renal pathology of HUS either alone or in synergy with Stx. Validation of this hypothesis could lead to a targeted anti-inflammatory approach aimed at modulating immune cell function in HUS.


Assuntos
Diarreia/imunologia , Infecções por Escherichia coli/imunologia , Síndrome Hemolítico-Urêmica/imunologia , Ativação Linfocitária/imunologia , Toxina Shiga I/imunologia , Toxina Shiga II/imunologia , Endotélio/imunologia , Escherichia coli/imunologia , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Infecções por Escherichia coli/microbiologia , Humanos , Mucosa Intestinal/citologia , Rim/imunologia , Linfócitos/imunologia , Trombose/imunologia
17.
Photochem Photobiol ; 71(5): 551-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10818785

RESUMO

We have previously demonstrated that the oxidizing component of ultraviolet-A (UVA) plays a central role in the activation of the nuclear oncogene and transcription factor, c-fos, in cultured human skin fibroblasts. We have now shown that expression of both c-jun and c-fos (AP-1) family of transcription factors is modulated by short and long wavelength solar ultraviolet (UV) radiation in human fibroblasts and human KB cells. UVA radiation activated c-jun and c-fos in both fibroblasts and KB cells, whereas ultraviolet-B (UVB) radiation activates such oncogenes only in KB cells. Moreover, decreasing the intracellular levels of reducing equivalents in human fibroblasts by glutathione (GSH) depletion lowered the UVA dose threshold for c-jun and c-fos activation several-fold and greatly amplified the UVA-mediated activation of such genes. A more modest effect was observed in GSH-depleted KB cells. In both GSH-depleted fibroblasts and KB cells, UVB radiation failed to amplify c-jun and c-fos activation indicating that the oxidative component of UVB plays a minor role in the modulation of such oncogene expression. These findings clearly indicate that both c-jun and c-fos are activated by the oxidizing component of UVA radiation in human fibroblasts and KB cells, while UVB-mediated modulation seems to be restricted to human epithelial cells and does not involve oxidizing intermediates.


Assuntos
Regulação da Expressão Gênica/efeitos da radiação , Genes fos , Genes jun , Pele/efeitos da radiação , Transcrição Gênica/efeitos da radiação , Linhagem Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Pele/citologia , Pele/metabolismo , Raios Ultravioleta
18.
Carcinogenesis ; 20(4): 727-32, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10223206

RESUMO

Exposure to solar ultraviolet (UV) B radiation is responsible for skin inflammation and tumour progression. Cyclooxygenase and ornithine decarboxylase are believed to be involved in such processes since they participate in the synthesis of mediators of inflammation and cell differentiation, respectively. We have investigated the in vitro modulation of expression of such genes by UVB radiation in different skin cell lines. We have observed that accumulation of ornithine decarboxylase mRNA is unaffected by even high UVB doses in both human epidermal keratinocytes and dermal fibroblasts, whereas cyclooxygenase-2 levels were significantly up-regulated by low UVB doses in KB human epidermoid keratinocytes. Depletion of total intracellular glutathione levels in KB cells amplified the activation, revealing a role for an oxidative component of UVB in modulating cyclooxygenase gene expression. Transfer of medium from UVB irradiated keratinocytes to fibroblasts resulted in a significant activation of cyclooxygenase expression and activity, while ornithine decarboxylase levels were unaffected. We conclude that UVB radiation can activate cyclooxygenase gene expression in human skin cells both by direct activation pathways or indirectly by inducing a paracrine mechanism.


Assuntos
Fibroblastos/efeitos da radiação , Isoenzimas/biossíntese , Queratinócitos/efeitos da radiação , Ornitina Descarboxilase/biossíntese , Prostaglandina-Endoperóxido Sintases/biossíntese , Pele/efeitos da radiação , Linhagem Celular Transformada/enzimologia , Linhagem Celular Transformada/efeitos da radiação , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Ciclo-Oxigenase 2 , Citocinas/metabolismo , Citocinas/farmacologia , Ativação Enzimática/efeitos da radiação , Indução Enzimática/efeitos da radiação , Epiderme/enzimologia , Epiderme/efeitos da radiação , Feto , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Glutationa/metabolismo , Humanos , Células KB/enzimologia , Células KB/efeitos da radiação , Queratinócitos/enzimologia , Masculino , Proteínas de Membrana , Proteínas de Neoplasias/biossíntese , Estresse Oxidativo , Pênis , Prostaglandinas/biossíntese , RNA Mensageiro/análise , RNA Neoplásico/análise , Pele/enzimologia
19.
Photochem Photobiol ; 69(4): 489-93, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10212582

RESUMO

Both broad-spectrum and near-monochromatic (334 nm, 365 nm and 405 nm) UVA (320-380 nm) and near-visible radiations strongly activate accumulation of mRNA corresponding to the nuclear oncogene and transcription factor, c-fos, in cultured human skin fibroblasts within a dose-range encountered in the environment. The oxidizing component of UVA is clearly of central importance to the activation observed because the absence of reduced glutathione strongly enhances the response. In contrast to observations in rodent cells, we observe negligible activation of the gene in human cells after UVB (290-320 nm) radiation. The results of this study provide evidence that UVA radiation strongly activates c-fos gene expression in human dermal fibroblasts, a phenomena that is likely to be reflected in UVA-mediated modulation of genes containing active AP-1-based enhancer elements in the promoter region.


Assuntos
Genes fos/efeitos da radiação , Animais , Linhagem Celular , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Fotobiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pele/metabolismo , Pele/efeitos da radiação , Raios Ultravioleta
20.
FEBS Lett ; 439(3): 253-7, 1998 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-9845332

RESUMO

We have investigated the modifying effects of epigallocatechin, a major polyphenolic constituent of green tea, on ultraviolet-A-activated gene expression in human fibroblasts and keratinocytes using the stress responsive enzymes: haem oxygenase-1, interstitial collagenase and cyclooxygenase-2. Although epigallocatechin strongly reduced ultraviolet-A-induced haem oxygenase-1 activation in skin-derived 'fibroblasts, the same compound activated collagenase and cyclooxygenase expression. In a keratinocyte cell line, ultraviolet-A-mediated haem oxygenase-1 over-expression was low and epigallocatechin failed to modulate it further. In contrast to the results with fibroblasts, ultraviolet-A activation of cyclooxygenase in keratinocytes was reduced by epigallocatechin. The results indicate that the effect of this green tea polyphenol on cellular stress responses is complex and may involve direct effects on signal transduction as well as changes that may be associated with its antioxidant activity.


Assuntos
Catequina/análogos & derivados , Colagenases/genética , Flavonoides/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Heme Oxigenase (Desciclizante)/genética , Prostaglandina-Endoperóxido Sintases/genética , Pele/efeitos da radiação , Raios Ultravioleta , Células Cultivadas , Fibroblastos/efeitos da radiação , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/efeitos da radiação , Humanos , Estresse Oxidativo , Pele/enzimologia , Chá/química , Células Tumorais Cultivadas
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