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1.
Arq Neuropsiquiatr ; 82(3): 1-8, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38438070

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) requires trained professionals for its adequate diagnosis. There is a shortage of such professionals in Brazil. Screening tools could identify priority cases. The only instrument for that in Brazilian Portuguese is employed for toddlers up to 2.5 years old. OBJECTIVE: The Mini-TEA scale was conceived and tested as a screening for children from 2.5 to 12 years old. METHODS: After local ethics committee's approval, this study was conducted from December 2022 to April 2023 in the Associação de Pais e Amigos dos Excepcionais, Passo Fundo/RS, of invitations to children's parents/relatives who were under evaluation for ASD and by local advertisement. Inclusion criteria were age from 2.5 to 12 years old; consent from the child's legal guardians. 75 children's parents/relatives were interviewed using the 15-item Mini-TEA scale. After that, children were evaluated for the diagnosis of ASD by a pediatric neurologist. Sensibility and specificity for ASD diagnosis along the Mini-TEA scores were measured. Experts and target population evaluated the validity/reliability of the Mini-TEA scale. The reproducibility of the scores was assessed about 40 days later. RESULTS: From the 75 participants, 28 received a diagnosis of ASD. Scores ≥ 10 on the Mini-TEA scale require further evaluation of the children (sensitivity 100%; specificity 68%). Content validity coefficient (CVC) rendered values > 0.80 (acceptable). Test-retest analyzes with the intraclass correlation coefficient (ICC) indicated excellent reliability (> 0.90). The time spent for applying the screening was about 10 minutes. CONCLUSION: The Mini-TEA scale presents as an easy tool for screening ASD among children.


ANTECEDENTES: O transtorno do espectro autista (TEA) requer profissionais treinados para o diagnóstico, escassos no Brasil. Instrumentos de triagem poderiam identificar casos prioritários para avaliação. O único em português brasileiro é empregado para crianças até 30 meses de idade. OBJETIVO: A escala Mini-TEA foi concebida e testada como triagem para crianças entre 2,5 e 12 anos. MéTODOS: Estudo foi conduzido de dezembro de 2022 a abril de 2023 na Associação de Pais e Amigos dos Excepcionais (APAE) de Passo Fundo/RS, após a aprovação bioética local. O recrutamento consistiu em convite aos familiares de crianças que estavam sendo avaliadas para TEA e por divulgação local. Os critérios de inclusão foram idade entre 2,5 e 12 anos e consentimento do guardião legal. Familiares de 75 crianças foram entrevistados com a escala Mini-TEA (15 itens). Depois, as crianças foram avaliadas para o diagnóstico de TEA por neuropediatra. A sensibilidade e a especificidade do diagnóstico de TEA com os escores da Mini-TEA foram mensuradas. A validade e a confiabilidade da escala Mini-TEA foram avaliadas por experts e pela população alvo. A reprodutibilidade dos escores foi medida após ± 40 dias. RESULTADOS: Dos 75 participantes, 28 receberam diagnóstico de TEA. Escores ≥ 10 na escala Mini-TEA requerem avaliação das crianças (sensibilidade 100%; especificidade 68%). O coeficiente de validação de conteúdo (CVC) rendeu valores > 0,80 (aceitável). Análises de teste-reteste com coeficiente de correlação intraclasse (ICC) indicou excelente confiabilidade (> 0,90). O tempo gasto para a triagem foi cerca de 10 minutos. CONCLUSãO: A escala Mini-TEA constitui ferramenta breve e fácil para triagem de TEA em crianças.


Assuntos
Transtorno do Espectro Autista , Criança , Humanos , Pré-Escolar , Transtorno do Espectro Autista/diagnóstico , Reprodutibilidade dos Testes , Brasil , Neurologistas
2.
Arq. neuropsiquiatr ; 82(3): s00441780517, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557125

RESUMO

Abstract Background Autism spectrum disorder (ASD) requires trained professionals for its adequate diagnosis. There is a shortage of such professionals in Brazil. Screening tools could identify priority cases. The only instrument for that in Brazilian Portuguese is employed for toddlers up to 2.5 years old. Objective The Mini-TEA scale was conceived and tested as a screening for children from 2.5 to 12 years old. Methods After local ethics committee's approval, this study was conducted from December 2022 to April 2023 in the Associação de Pais e Amigos dos Excepcionais, Passo Fundo/RS, of invitations to children's parents/relatives who were under evaluation for ASD and by local advertisement. Inclusion criteria were age from 2.5 to 12 years old; consent from the child's legal guardians. 75 children's parents/relatives were interviewed using the 15-item Mini-TEA scale. After that, children were evaluated for the diagnosis of ASD by a pediatric neurologist. Sensibility and specificity for ASD diagnosis along the Mini-TEA scores were measured. Experts and target population evaluated the validity/reliability of the Mini-TEA scale. The reproducibility of the scores was assessed about 40 days later. Results From the 75 participants, 28 received a diagnosis of ASD. Scores ≥ 10 on the Mini-TEA scale require further evaluation of the children (sensitivity 100%; specificity 68%). Content validity coefficient (CVC) rendered values > 0.80 (acceptable). Test-retest analyzes with the intraclass correlation coefficient (ICC) indicated excellent reliability (> 0.90). The time spent for applying the screening was about 10 minutes. Conclusion The Mini-TEA scale presents as an easy tool for screening ASD among children.


Resumo Antecedentes O transtorno do espectro autista (TEA) requer profissionais treinados para o diagnóstico, escassos no Brasil. Instrumentos de triagem poderiam identificar casos prioritários para avaliação. O único em português brasileiro é empregado para crianças até 30 meses de idade. Objetivo A escala Mini-TEA foi concebida e testada como triagem para crianças entre 2,5 e 12 anos. Métodos Estudo foi conduzido de dezembro de 2022 a abril de 2023 na Associação de Pais e Amigos dos Excepcionais (APAE) de Passo Fundo/RS, após a aprovação bioética local. O recrutamento consistiu em convite aos familiares de crianças que estavam sendo avaliadas para TEA e por divulgação local. Os critérios de inclusão foram idade entre 2,5 e 12 anos e consentimento do guardião legal. Familiares de 75 crianças foram entrevistados com a escala Mini-TEA (15 itens). Depois, as crianças foram avaliadas para o diagnóstico de TEA por neuropediatra. A sensibilidade e a especificidade do diagnóstico de TEA com os escores da Mini-TEA foram mensuradas. A validade e a confiabilidade da escala Mini-TEA foram avaliadas por experts e pela população alvo. A reprodutibilidade dos escores foi medida após ± 40 dias. Resultados Dos 75 participantes, 28 receberam diagnóstico de TEA. Escores ≥ 10 na escala Mini-TEA requerem avaliação das crianças (sensibilidade 100%; especificidade 68%). O coeficiente de validação de conteúdo (CVC) rendeu valores > 0,80 (aceitável). Análises de teste-reteste com coeficiente de correlação intraclasse (ICC) indicou excelente confiabilidade (> 0,90). O tempo gasto para a triagem foi cerca de 10 minutos. Conclusão A escala Mini-TEA constitui ferramenta breve e fácil para triagem de TEA em crianças.

3.
Mult Scler J Exp Transl Clin ; 5(4): 2055217319894604, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31897308

RESUMO

BACKGROUND: Poly (ADP-ribose) polymerase 1 (PARP-1) plays pivotal roles in immune and inflammatory responses. Accumulating evidence suggests PARP-1 as a promising target for immunomodulation in multiple sclerosis and natalizumab-associated progressive multifocal leukoencephalopathy. OBJECTIVE: This study explores expression of PARP-1 and downstream effectors in multiple sclerosis and during natalizumab treatment. METHODS: Transcriptional expressions were studied by real-time reverse transcriptase polymerase chain reaction on CD4+T/CD8+T/CD14+/B cells and peripheral blood mononuclear cells from healthy volunteers, untreated and natalizumab-treated non-progressive multifocal leukoencephalopathy and progressive multifocal leukoencephalopathy multiple sclerosis patients. RESULTS: PARP-1 expression was higher in CD4+T, CD8+T and B cells from untreated patients compared to healthy volunteers. Natalizumab treatment restored deregulated PARP-1 expression in T cells but not in B cells. Sustained upregulation of PARP-1 was associated with decreased expression of downstream PARP-1 factors such as TGFBR1/TGFBR2/BCL6 in B cells. Notably, a higher expression of PARP-1 was detected in progressive multifocal leukoencephalopathy patients. CONCLUSIONS: Given the importance of PARP-1 in inflammatory processes, its upregulation in multiple sclerosis lymphocyte populations suggests a potential role in the immune pathogenesis of multiple sclerosis. Strikingly higher PARP-1 expression in progressive multifocal leukoencephalopathy cases suggests its involvement in progressive multifocal leukoencephalopathy disease pathomechanisms. These results further support the value of PARP-1 inhibitors as a potential novel therapeutic strategy for multiple sclerosis and natalizumab-associated progressive multifocal leukoencephalopathy.

4.
Neurol Neuroimmunol Neuroinflamm ; 3(3): e223, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27088119

RESUMO

OBJECTIVES: To assess messenger RNA (mRNA) expression of POU2AF1 and Spi-B and their potential regulatory microRNAs (miRNAs) in natalizumab-treated patients with multiple sclerosis and in therapy-associated progressive multifocal leukoencephalopathy (PML). METHODS: Expression of POU2AF1/Spi-B was analyzed by using real-time reverse transcription PCR assays on isolated B/CD8(+) T lymphocytes and peripheral blood mononuclear cells (PBMCs) from cohorts of untreated and natalizumab-treated patients with and without PML. Longitudinal expression analysis was performed on CD4(+), CD8(+) T and B cells from 14 patients who interrupted natalizumab therapy for 8 weeks. The miRNA profiling was conducted in PBMCs from 5 untreated and 5 natalizumab-treated patients using low-density arrays followed by validation with single miRNAs assays in untreated and natalizumab-treated patients. RESULTS: POU2AF1 and Spi-B mRNAs were upregulated in B and CD8(+) T cells from natalizumab-treated patients, which was validated in PBMCs from different cohorts of natalizumab-treated patients with and without PML, with a noteworthy higher expression of Spi-B in patients with PML. In contrast, downregulation of POU2AF1/Spi-B expression was measured in B and CD8(+) T cells after natalizumab discontinuation. Seventeen differentially expressed miRNAs including miR-10b, a regulator of POU2AF1 mRNA, were identified in long-term natalizumab-treated patients compared with untreated ones. CONCLUSIONS: Upregulation of POU2AF1 and Spi-B, known transactivators of the JC virus, the causative agent for PML, and its association with occurrence of PML in natalizumab-treated patients, corroborates POU2AF1/Spi-B as potential biomarkers for PML risk, which merits further evaluation.

5.
J Immunol Res ; 2014: 897249, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24901013

RESUMO

MicroRNAs (miRNAs) are a family of noncoding RNAs that play critical roles in the posttranscriptional regulation of gene expression. Accumulating evidence supports their involvement in the pathogenesis of multiple sclerosis (MS). Here, we compare miR-17 expressions in CD4+ T cells from relapsing-remitting (RR) MS patients treated with natalizumab versus untreated patients. miR-17 was downregulated under natalizumab treatment and upregulated during relapse, therefore supporting a possible role of miR-17 in MS immunopathogenesis. Downregulation of miR-17 was associated with upregulation of PTEN, BIM, E2F1, and p21 target genes. In vitro miR-17 inhibition was associated with upregulation of the same targets and resulted in impaired CD4+ T cell activation and proliferation. We further describe deregulated TGFBR2 expression in untreated patients versus healthy volunteers (HVs) and confirm in vitro the link between miR-17 and TGFBR2 expressions. These findings support an effect of natalizumab on expression of specific miRNA and subsequent expression of genes involved in proliferation and control of the cell cycle.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , MicroRNAs/genética , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adulto , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/imunologia , Proteína 11 Semelhante a Bcl-2 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Estudos de Casos e Controles , Ciclo Celular/efeitos dos fármacos , Inibição de Migração Celular , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/imunologia , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/imunologia , Feminino , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , MicroRNAs/imunologia , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/genética , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/patologia , Natalizumab , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/imunologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/imunologia , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/imunologia , Transdução de Sinais
6.
Mult Scler ; 20(10): 1363-70, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24598267

RESUMO

BACKGROUND: MicroRNAs (miRNAs) have emerged as a family of post-transcriptional regulators of gene expression that mediate diverse aspects of immunity. MiRNA dysregulation has been found in multiple sclerosis (MS), reflecting the growing need to identify disease-specific miRNA expression signatures. Our previous low-density array studies reveal differential miR-126 expression in the CD4(+)T cells of untreated relapsing-remitting MS (RRMS) patients. Here, we investigated miR-126 expression in natalizumab-treated patients. METHODS: We isolated CD4(+) T cells from untreated (n = 12) and natalizumab-treated MS patients (n = 24), and from healthy volunteers (n = 12). We analyzed the expression of miRNAs and potential targets by real time reverse transcription polymerase chain reaction (RT-PCR). We assessed specific inhibition of miR-126, in vitro. RESULTS: MiR-126 was down-regulated in cells of patients under natalizumab treatment and up-regulated during relapse, supporting a regulatory role in MS immunopathogenesis. MiR-126 expression correlated with the expression of POU2AF1, a regulator of Spi-B that binds to the promoter/enhancer sequences of JC virus (JCV), the pathogen of progressive multifocal leukoencephalopathy (PML), a rare complication of natalizumab treatment. The same trend was found for Spi-B. Strong up-regulation of both genes appeared to be treatment duration-dependent. Specific inhibition experiments supported the link between the expression of miR-126 and POU2AF1/Spi-B. CONCLUSIONS: Our findings provided deeper insight into the mode of action of natalizumab, with possible implications for understanding both the effects of natalizumab on MS activity and its specific adverse event profile.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Linfócitos T CD4-Positivos/efeitos dos fármacos , Imunossupressores/uso terapêutico , MicroRNAs/metabolismo , Esclerose Múltipla/tratamento farmacológico , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Imunossupressores/efeitos adversos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Natalizumab , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Resultado do Tratamento
7.
Clin Immunol ; 144(1): 70-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22659298

RESUMO

MicroRNAs (miRNAs) are posttranscriptional regulators of gene expression. We compared the expression of 1059 miRNAs in B lymphocytes from untreated and natalizumab treated relapsing-remitting multiple sclerosis (RRMS) patients and healthy volunteers (HV). Forty nine miRNAs were down-regulated in untreated MS patients compared with HV. A distinct pattern of 10 differentially expressed miRNAs was found in natalizumab treated patients compared with untreated patients. Two clusters, i.e. miR-106b-25 and miR-17-92, were particularly deregulated. MiRNA-mRNA interaction analysis revealed B cell receptor, phosphatidyl-inositol-3-kinase (PI3K) and phosphatase and tensin homology (PTEN) signaling being the key affected pathways. We discovered deregulated viral miRNAs in untreated patients as compared with HV and natalizumab treated patients, a novel finding that may be related to latency and activation of viruses in MS. Our findings provide first insights into miRNA dependent regulation of B cell function in MS and the impact of a therapy not primarily targeting B cells on this regulation.


Assuntos
Linfócitos B/imunologia , MicroRNAs/imunologia , Esclerose Múltipla Recidivante-Remitente/imunologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Feminino , Humanos , Masculino , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/genética , Natalizumab
8.
Eur J Immunol ; 40(3): 888-98, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20148420

RESUMO

MicroRNA (miRNA) are a class of post-transcriptional regulators of gene expression targeting mRNA for translational repression and/or degradation. We analyzed the expression of 365 miRNA in lymphocytes in relapsing-remitting MS patients, and show the first evidence for distinct miRNA expression profiles in CD4(+), CD8(+) and B cells in MS when compared with those in healthy volunteers. MiR-17-5p, which is involved in autoimmunity, was up-regulated in CD4(+) cells from MS patients. This was correlated with alterations in the expression of potential target genes of miR-17-5p, i.e. phosphatase and tensin homology and phosphatidyl-inositol-3-kinase regulatory subunit 1, which were down-regulated upon stimulation of CD4(+) cells with anti-CD3/CD28 in vitro. Functional experiments with a synthetic inhibitor of miR-17 supported the link between miRNA expression and the altered target gene expression. Moreover, we found distinct responses of deregulated miRNA to stimulation, i.e. miR-17-5p and miR-193a were strongly up-regulated, in contrast to the down-regulation of miR-497, miR-1 and miR-126. Other deregulated miRNA did not respond to the stimulation probably due to other, non-T-cell activation related, mechanisms in their mode of action. Our findings support the role of miRNA-dependent regulatory mechanisms in the immunopathogenesis of MS.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Perfilação da Expressão Gênica , MicroRNAs/biossíntese , Esclerose Múltipla Recidivante-Remitente/genética , Linfócitos B/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Separação Celular , Feminino , Citometria de Fluxo , Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
J Neuroimmunol ; 194(1-2): 153-64, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18178259

RESUMO

Natalizumab, the most recently approved treatment for relapsing multiple sclerosis (MS) exerts its action through binding to alpha4 integrins. We studied longitudinally gene expression profiles in peripheral blood of MS patients, treated with natalizumab for more than 2 years. The majority of altered genes relates to immune response, signal transduction, adhesion and metabolism. Not only gene expression relevant for T lymphocytes was altered, but also genes regulating B-lymphocyte, neutrophil and erythrocyte functions. Understanding these different gene effects and their interrelationships will provide more insights into additional mechanisms of action of natalizumab and possibly allow better prediction of adverse events.


Assuntos
Anticorpos Monoclonais/farmacologia , Células Sanguíneas/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Esclerose Múltipla/sangue , Transcrição Gênica/efeitos dos fármacos , Adulto , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Células Sanguíneas/metabolismo , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Citocinas/sangue , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Feminino , Seguimentos , Humanos , Imunidade/genética , Integrina alfa4/imunologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Natalizumab , Ensaios Clínicos Controlados Aleatórios como Assunto , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
10.
J Neurol ; 254(2): 160-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17334662

RESUMO

OBJECTIVE: We investigated the correlation of antimyelin oligodendrocyte glycoprotein-(anti-MOG) and anti-myelin basic protein antibodies (anti-MBP) in serum of CIS patients with inflammatory signs in MRI and in CSF and, as previously suggested,the incidence of more frequent and rapid progression to clinically definite MS (CDMS). METHODS: 133CIS patients were analysed for anti-MOG and anti-MBP (Western blot). Routine CSF and cranial MRI (quantitatively and qualitatively) measures were analyzed. 55 patients had a follow-up of at least 12 months or until conversion to CDMS. RESULTS: Patients with anti-MOG and anti-MBP had an increased intrathecal IgG production and CSF white blood cell count(p = 0.048 and p = 0.036). When anti-MBP alone, or both antibodies were present the cranial MRI showed significantly more T2 lesions (p = 0.007 and p = 0.01,respectively). There was a trend for more lesion dissemination in anti-MBP positive patients (p = 0.076).Conversely, anti-MOG- and/or anti-MBP failed to predict conversion to CDMS in our follow-up group (n = 55). Only in female patients with at least one MRI lesion (n = 34) did the presence of anti-MOG correlate with more frequent (p = 0.028) and more rapid (p = 0.0209) transition to CDMS. CONCLUSIONS: Presence of anti-MOG or anti-MBP or both was not significantly associated with conversion to CDMS in our CIS cohort. However, patients with anti-MOG and anti-MBP had higher lesion load and more disseminated lesions in cranial MRI as well as higher values for CSF leucocytes and intrathecal IgG production. Our data support a correlation of anti-MOG and anti-MBP to inflammatory signs in MRI and CSF. The prognostic value of these antibodies for CDMS, however, seems to be less pronounced than previously reported.


Assuntos
Anticorpos/líquido cefalorraquidiano , Inflamação , Imageamento por Ressonância Magnética , Esclerose Múltipla , Proteína Básica da Mielina/imunologia , Glicoproteína Associada a Mielina/imunologia , Adulto , Distribuição de Qui-Quadrado , Feminino , Seguimentos , Humanos , Inflamação/líquido cefalorraquidiano , Inflamação/complicações , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/complicações , Esclerose Múltipla/patologia , Proteínas da Mielina , Glicoproteína Mielina-Oligodendrócito , Estudos Retrospectivos , Estatísticas não Paramétricas
11.
Biol Chem ; 386(11): 1157-64, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16307481

RESUMO

Previous work has demonstrated that the function of extrahepatic cytochrome P450 CYP1A1 is dependent on the availability of heme. CYP1A1 is involved in the activation of polyaromatic hydrocarbons. In the present study we used a transgenic mouse model with chronic impairment of heme synthesis - female porphobilinogen deaminase-deficient (PBGD-/-) mice - to investigate the effects of limited heme in untreated and beta-naphthoflavone (beta-NF)-treated animals on the function of CYP1A1 in brain. The heme content of PBGD-/- mice was diminished in the liver and brain compared to wild types. In the liver, partial heme deficiency led to less potent induction of CYP1A1 mRNA after beta-NF treatment. In the brain, CYP1A1 protein was detected not only at the endoplasmic reticulum (ER), but also in the cytosol of PBGD-/- mice. Furthermore, 7-deethylation of ethoxyresorufin, an indicator of CYP1A1 metabolic activity, could be restored by heme in cytosol of PBGD-/- mouse brain. Independent of the genotype, we found only one cyp1a1 gene product, indicating that the cytosolic appearance of CYP1A1 most likely did not originate from mutant alleles. We conclude that heme deficiency in the brain leads to incomplete heme saturation of CYP1A1, which causes its improper incorporation into the ER membrane and persistence in the cytosol. It is suggested that diseases caused by relative heme deficiency, such as hepatic porphyrias, may lead to impaired hemoprotein function in brain.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Citosol/enzimologia , Heme/deficiência , Erros Inatos do Metabolismo/enzimologia , Animais , Encéfalo/enzimologia , Doença Crônica , Citocromo P-450 CYP1A1/genética , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Feminino , Genótipo , Heme/análise , Hidroximetilbilano Sintase/genética , Fígado/enzimologia , Erros Inatos do Metabolismo/genética , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , Frações Subcelulares/enzimologia , beta-Naftoflavona/farmacologia
12.
J Neuroimmunol ; 152(1-2): 154-67, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15223248

RESUMO

We used microarrays to compare the gene expression profile in active lesions and donor-matched normal appearing white matter (NAWM) from brain autopsy samples of patients with secondary progressive multiple sclerosis (MS) with that from controls who died from non-neurological diseases. The 123 genes in lesions, and 47 genes in NAWM(MS) were differentially expressed. Lesions distinguished from NAWM(MS) by a higher expression of genes related to immunoglobulin synthesis and neuroglial differentiation, while cellular immune response elements were equally dysregulated in both tissue compartments. Current results provide molecular evidence of a continuum of dysfunctional homeostasis and inflammatory changes between lesions and NAWM(MS), and support the concept of MS pathogenesis being a generalised process that involves the entire CNS.


Assuntos
Encéfalo/patologia , Regulação da Expressão Gênica/fisiologia , Esclerose Múltipla/genética , Perfilação da Expressão Gênica , Humanos , Esclerose Múltipla/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Brain ; 127(Pt 2): 259-68, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14607790

RESUMO

Neutralizing antibodies (NAb) against interferon-beta (IFN-beta) develop in about a third of treated multiple sclerosis patients and are believed to reduce therapeutic efficacy of IFN-beta on clinical and MRI measures. The expression of the interferon acute-response protein, myxovirus resistance protein A (MxA) is a sensitive measure of the biological activity of therapeutically applied IFN-beta and of its reduced bioavailability due to NAb. However, MxA may not be operative in the pathogenesis of multiple sclerosis or the therapeutic effect of IFN-beta. Instead, matrix metalloproteinases (MMPs) are increased in brain tissue, CSF and blood circulation of multiple sclerosis patients and function as effector molecules in several steps of multiple sclerosis pathogenesis. One of the molecular mechanisms by which IFN-beta exerts its beneficial effect in multiple sclerosis is reduction of MMP-9 expression and increase of its endogenous tissue inhibitor, TIMP-1. Quantitative PCR measurements of MMP-2 and MMP-9, TIMP-1 and TIMP-2, and MxA were performed in peripheral mononuclear cells from clinically stable multiple sclerosis patients with relapsing remitting disease course after short-term and long-term treatment with IFN-beta. IFN-beta therapy down-regulated the expression of MMP-9 and abolished that of MMP-2 in long-term, but not short-term treated multiple sclerosis, while levels of MxA were increased in both instances. The presence of NAb reversed these effects, i.e. led to reduced MxA and increased MMP-2/MMP-9 expression levels compared with NAb- patients. In contrast, expression of TIMPs in peripheral blood mononuclear cells remained unaffected by IFN-beta therapy and the presence of NAb. While MxA is able to detect the biological action and reduced bioavailability of IFN-beta on the basis of single injections, only MMP-9 shows quantitative correlation with the NAb titre. Together with evidence that an imbalance between MMP and TIMP expression is a crucial pathogenetic feature in multiple sclerosis, these findings support the concept of a significant role of NAb in reducing the therapeutic efficacy of IFN-beta.


Assuntos
Inibidores Enzimáticos/imunologia , Interferon beta/antagonistas & inibidores , Inibidores de Metaloproteinases de Matriz , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Anticorpos/imunologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Proteínas de Ligação ao GTP/sangue , Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon beta/imunologia , Interferon beta/uso terapêutico , Masculino , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/sangue , Metaloproteinase 9 da Matriz/genética , Metaloproteinases da Matriz/sangue , Metaloproteinases da Matriz/genética , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/enzimologia , Proteínas de Resistência a Myxovirus , Estudos Retrospectivos , Inibidor Tecidual de Metaloproteinase-1/sangue , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-2/sangue , Inibidor Tecidual de Metaloproteinase-2/genética
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