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1.
Behav Neurosci ; 130(6): 600-613, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27657308

RESUMO

A fundamental task of sensory systems is to extract relevant social information from a range of environmental stimuli in the face of changing behavioral contexts and reproductive states. Neuromodulatory pathways that interact with such contextual variables are 1 mechanism for achieving this. In the mouse inferior colliculus (IC), a midbrain auditory region, the neuromodulator serotonin increases in females interacting with courting males, but events downstream of serotonin release have not been investigated. Here, we manipulated serotonin levels in female mice with the serotonin releaser fenfluramine or the serotonin depleter para-chlorophenylalaninemethyl ester (pCPA). Females were then exposed to an empty cage, a male partner, or a playback of courtship vocalizations, and the numbers of neurons in the IC with positive immunoreactivity for the immediate early gene product c-Fos were measured. The effects of drug treatments depended on social context and estrous state. Fenfluramine had greater effects in the nonsocial than in the partner social treatments. Females in proestrus or estrus and given fenfluramine had higher densities of c-Fos immunoreactive neurons, while females in diestrus had fewer immunoreactive neurons. The drug pCPA had the expected opposite effect of fenfluramine, causing a decreased response in pro/estrus females and an increased response in diestrus females. These findings show that the effects of serotonin on c-Fos activity in the IC of females is dependent on both external context and reproductive state, and suggest that these effects occur downstream of serotonin release. (PsycINFO Database Record


Assuntos
Estro , Genes fos/genética , Colículos Inferiores/metabolismo , Serotonina/metabolismo , Meio Social , Estimulação Acústica , Anestésicos Inalatórios/administração & dosagem , Animais , Enflurano/administração & dosagem , Feminino , Genes fos/imunologia , Humanos , Colículos Inferiores/citologia , Camundongos , Fatores de Tempo
2.
Cell Mol Immunol ; 10(5): 413-22, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23892429

RESUMO

There is increasing awareness of the effects of Porphyromonas gingivalis on host immune responses. Degradation of cytokines and chemokines by cysteine proteinases has previously been reported. However, the precise mechanisms by which P. gingivalis is able to alter intracellular signaling, and thus proliferation and inflammation, have not been described. We have previously reported suppression of activator protein-1 (AP-1) and degradation of IL-2 by proteinases from P. gingivalis. In the present study, we have analyzed the effects of P. gingivalis on Jurkat T-cell signal transduction and subsequent IL-2 and CXCL8 expression. We found that CXCL8, but not IL-2, gene expression levels were significantly suppressed by viable P. gingivalis. Analysis of intracellular signaling revealed an inhibitory effect of P. gingivalis on c-Jun and c-Fos, but not NFκB (p50 and p65), NFAT or STAT5 expression. This inhibitory effect was not due to suppression of mitogen-activated protein kinase (MAPK) (p38, erk and JNK) gene expression, but was rather due to prevention of protein kinase C (PKC) and p38 phosphorylation, as demonstrated by western blot analysis. Furthermore, SOCS1 and SOCS3 expression levels decreased following treatment of Jurkat T cells with viable P. gingivalis. The results indicate that P. gingivalis is able to suppress inflammatory gene expression by targeting the activity of MAPK pathways in T cells, which was confirmed by using specific inhibitors of NF-κB, PKC, ERK, p38 and JNK.


Assuntos
Expressão Gênica/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Porphyromonas gingivalis/fisiologia , Técnicas de Cocultura , Regulação para Baixo , Genes fos/genética , Genes fos/imunologia , Humanos , Inflamação/imunologia , Inflamação/microbiologia , Inflamação/patologia , Interleucina-2/genética , Interleucina-2/imunologia , Interleucina-8/genética , Interleucina-8/imunologia , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/imunologia , Células Jurkat , Sistema de Sinalização das MAP Quinases/genética , NF-kappa B/genética , NF-kappa B/imunologia , Fosforilação , Proteína Quinase C/genética , Proteína Quinase C/imunologia , Proteína 1 Supressora da Sinalização de Citocina , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/imunologia , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
3.
Molecules ; 17(5): 5404-11, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22569419

RESUMO

This study investigated the immunostimulatory effects of laminarin with respect to inflammatory mediators such as hydrogen peroxide, calcium, nitric oxide, various cytokines, transcription factors, and immune response gene in RAW 264.7 mouse macrophages. Laminarin did not reduce the cell proliferation of RAW 264.7 mouse macrophages at concentrations up to 500 µg/mL. Laminarin significantly increased the release of hydrogen peroxide, calcium, nitric oxide, monocyte chemotactic protein-1, vascular endothelial growth factor, leukemia inhibitory factor, and granulocyte-colony stimulating factor with enhancing expression of Signal Transducer and Activator of Transcription 1 (STAT1), STAT3, c-Jun, c-Fos, and cyclooxygenase-2 mRNA in RAW 264.7 cells. The results suggest that laminarin has immunostimulatory properties, strengthening immune reactions via the transcription factor pathway in macrophages.


Assuntos
Expressão Gênica/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Macrófagos/efeitos dos fármacos , Polissacarídeos/farmacologia , Animais , Cálcio/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quimiocina CCL2/genética , Quimiocina CCL2/imunologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/imunologia , Expressão Gênica/imunologia , Genes fos/genética , Genes fos/imunologia , Genes jun/genética , Genes jun/imunologia , Glucanos , Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos/imunologia , Peróxido de Hidrogênio/metabolismo , Fator Gênico 3 Estimulado por Interferon/genética , Fator Gênico 3 Estimulado por Interferon/imunologia , Fator Inibidor de Leucemia/genética , Fator Inibidor de Leucemia/imunologia , Macrófagos/citologia , Macrófagos/imunologia , Camundongos , Óxido Nítrico/biossíntese , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia
4.
Hum Immunol ; 73(5): 448-55, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22425740

RESUMO

MUC1 mucin, primarily known as an epithelial antigen, has been demonstrated to be expressed on activated human T cells. In the present study, we first examined the expression of MUC1 on different subsets of T cells (naive, effector, effector/memory). MUC1 appears to be strongly upregulated on activated CD4(+) T cells in comparison with CD8(+) T cells. The cytoplasmic tail of MUC1 contains both immune tyrosine-based activation and inhibitory motifs; therefore, we investigated whether MUC1 can also act as a costimulatory molecule on human T cells. Nonpurified T-cell cultures from human peripheral blood exhibited enhanced proliferation and an increase in cytokine production when CD3 and MUC1 were cross-linked and coligated. The intracellular mechanism of MUC1-mediated costimulation was determined to be mediated by the calcium-dependent NF-AT pathway. We further demonstrated that the cytoplasmic tail of MUC1 binds to the AP-1 transcription factors c-Fos and c-Jun, with c-Fos binding constitutively and c-Jun binding only after MUC1 stimulation. Their nuclear migration is then facilitated in a CD3-dependent manner. Our findings clearly demonstrate that MUC1 is a novel T-cell costimulatory molecule involved in immune regulation. These studies delineate important mechanisms of T-cell activation and regulation.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Mucina-1/imunologia , Transdução de Sinais/imunologia , Fator de Transcrição AP-1/imunologia , Adulto , Anticorpos/química , Anticorpos/imunologia , Complexo CD3/genética , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Reagentes de Ligações Cruzadas/química , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Expressão Gênica/imunologia , Genes fos/genética , Genes fos/imunologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Pessoa de Meia-Idade , Mucina-1/genética , Fito-Hemaglutininas/farmacologia , Ligação Proteica , Estrutura Terciária de Proteína , Transporte Proteico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Transcrição AP-1/genética
5.
J Biol Chem ; 285(8): 5488-96, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20028981

RESUMO

Ras-related nuclear protein (Ran) is a Ras family GTPase, and its documented functions are the regulation of DNA replication, cell cycle progression, nuclear structure formation, RNA processing and exportation, and nuclear protein importation. In this study, we performed detailed mapping of Ran expression during mouse ontogeny using in situ hybridization. High Ran expression was found in various organs and tissues including the thymus cortex and spleen white pulp. Ran was induced in T cells 24 h after their activation. The function of Ran in the immune system was investigated using Ran transgenic (Tg) mice. In Ran Tg T cells, there was compromised activation marker expression, lymphokine secretion, and proliferation upon T cell receptor activation in vitro when compared with wild type T cells. Tg mice also manifested defective delayed type hypersensitivity in vivo. Upon PMA and ionomycin stimulation, Tg T cells were defective in nuclear accumulation of AP-1 factors (c-Jun and c-Fos) but not NF-kappaB family members. Our experiments showed that Ran had important regulatory function in T cell activation. One of the possible mechanisms is that intracellular Ran protein levels control the nuclear retention for selective transcription factors such as c-Jun and c-Fos of AP-1, which is known to be critical in T cell activation and proliferation and lymphokine secretion.


Assuntos
Genes fos/imunologia , Genes jun/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Fator de Transcrição AP-1/imunologia , Proteína ran de Ligação ao GTP/imunologia , Animais , Proliferação de Células/efeitos dos fármacos , Citocinas/biossíntese , Citocinas/genética , Citocinas/imunologia , Hipersensibilidade Tardia/genética , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Tardia/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Proteína ran de Ligação ao GTP/genética , Proteína ran de Ligação ao GTP/metabolismo
6.
Eur J Immunol ; 39(9): 2584-95, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19701889

RESUMO

TCR signaling leads to the activation of kinases such as inducible tyrosine kinase (Itk), a key regulatory protein in T-lymphocyte activation and function. The homolog of Itk in B cells is Bruton's tyrosine kinase, previously shown to bind and phosphorylate the transcription factor TFII-I. TFII-I plays major roles in transcription and signaling. Our purpose herein was twofold: first, to identify some of the molecular determinants involved in TFII-I activation downstream of receptor crosslinking in T cells and second, to uncover the existence of Itk-TFII-I signaling in T lymphocytes. We report for the first time that TFII-I is tyrosine phosphorylated upon TCR, TCR/CD43, and TCR/CD28 co-receptor engagement in human and/or murine T cells. We show that Itk physically interacts with TFII-I and potentiates TFII-I-driven c-fos transcription. We demonstrate that TFII-I is phosphorylated upon co-expression of WT, but not kinase-dead, or kinase-dead/R29C mutant Itk, suggesting these residues are important for TFII-I phosphorylation, presumably via an Itk-dependent mechanism. Structural analysis of TFII-I-Itk interactions revealed that the first 90 residues of TFII-I are dispensable for Itk binding. Mutations within Itk's kinase, pleckstrin-homology, and proline-rich regions did not abolish TFII-I-Itk binding. Our results provide an initial step in understanding the biological role of Itk-TFII-I signaling in T-cell function.


Assuntos
Linfócitos B/imunologia , Proteínas Tirosina Quinases/metabolismo , Linfócitos T/imunologia , Fatores de Transcrição TFII/metabolismo , Animais , Linfócitos B/metabolismo , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Complexo CD3/imunologia , Complexo CD3/metabolismo , Genes fos/genética , Genes fos/imunologia , Humanos , Células Jurkat , Leucossialina/imunologia , Leucossialina/metabolismo , Camundongos , Fosforilação/imunologia , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/imunologia , Linfócitos T/metabolismo
7.
Psychopharmacology (Berl) ; 201(1): 1-13, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18813914

RESUMO

UNLABELLED: OBJECTIVES AND MATERIALS AND METHODS: The aims of the present study were (1) to determine the neuronal activation pattern elicited by the group II mGlu antagonist LY341495 and (2) to evaluate the contribution of each group II mGlu subtype by using wild-type (WT) and knockout (KO) mice lacking either mGlu2 or mGlu3. c-Fos expression was used as a marker of neuronal activation. RESULTS AND DISCUSSION: In WT mice, LY341495 induced widespread c-Fos expression in 68 out of 92 brain areas, including limbic areas such as the amygdala, septum, prefrontal cortex, and hippocampus. LY341495-induced c-Fos response was markedly decreased in the medial part of the central amygdala (CeM) and lateral septum (LS) in mGlu3-KO mice, as well as in the lateral parabrachial nucleus (LPB) in both KO strains. In the majority of investigated areas, LY341495-induced c-Fos expression was similar in KO and WT mice. Analysis of the cellular and subcellular distribution of mGlu2 and mGlu3 revealed a prevailing presence of mGlu3-immunoreactivity in the CeM in glial processes and in postsynapstic neuronal elements, whereas only rare presynaptic axon terminals were found immunoreactive for mGlu2. CONCLUSION: In conclusion, our data indicate that group II mGlu blockade increases neuronal activation in a variety of brain areas, including many stress- and anxiety-related areas. The activation of two key brain areas, the CeM and LS, is mediated via mGlu3, while activation in the LPB involves both subtypes. Moreover, in the majority of investigated areas, LY341495-mediated neuronal activation appears to require a complex cross talk between group II mGlu subtypes or the action of LY341495 on additional receptors.


Assuntos
Antagonistas de Aminoácidos Excitatórios/farmacologia , Genes fos/efeitos dos fármacos , Genes fos/genética , Receptores de Glutamato Metabotrópico/deficiência , Aminoácidos/farmacologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/ultraestrutura , Animais , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Genes fos/imunologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/ultraestrutura , Receptores de Glutamato Metabotrópico/genética , Receptores de Glutamato Metabotrópico/imunologia , Septo do Cérebro/efeitos dos fármacos , Septo do Cérebro/metabolismo , Septo do Cérebro/ultraestrutura , Xantenos/farmacologia
8.
J Leukoc Biol ; 80(3): 640-50, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16829632

RESUMO

Human T cell leukemia virus type 1 (HTLV-1) has previously been shown to infect antigen-presenting cells and their precursors in vivo. However, the role these important cell populations play in the pathogenesis of HTLV-1-associated myelopathy/tropical spastic paraparesis or adult T cell leukemia remains unresolved. To better understand how HTLV-1 infection of these important cell populations may potentially impact disease progression, the regulation of HTLV-1 viral gene expression in established monocytic cell lines was examined. U-937 promonocytic cells transiently transfected with a HTLV-1 long-terminal repeat (LTR) luciferase construct were treated with phorbol 12-myristate 13-acetate (PMA) to induce cellular differentiation. PMA-induced cellular differentiation resulted in activation of basal and Tax-mediated transactivation of the HTLV-1 LTR. In addition, electrophoretic mobility shift analyses demonstrated that PMA-induced cellular differentiation induced DNA-binding activity of cellular transcription factors to Tax-responsive element 1 (TRE-1) repeat II. Supershift analyses revealed that factors belonging to the activator protein 1 (AP-1) family of basic region/leucine zipper proteins (Fra-1, Fra-2, JunB, and JunD) were induced to bind to TRE-1 repeat II during cellular differentiation. Inhibition of AP-1 DNA-binding activity by overexpression of a dominant-negative c-Fos mutant (A-Fos) in transient expression analyses resulted in severely decreased levels of HTLV-1 LTR activation in PMA-induced U-937 cells. These results have suggested that following infection of peripheral blood monocytes, HTLV-1 viral gene expression may become up-regulated by AP-1 during differentiation into macrophages or dendritic cells.


Assuntos
Regulação Viral da Expressão Gênica/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Monócitos/imunologia , Monócitos/virologia , Fator de Transcrição AP-1/fisiologia , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Produtos do Gene tax/imunologia , Genes fos/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Dados de Sequência Molecular , Monócitos/efeitos dos fármacos , Ligação Proteica , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologia , Regulação para Cima/imunologia
9.
Int Immunol ; 16(10): 1477-86, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15339880

RESUMO

We examined effects of c-fos overexpression on the development and property of peritoneal B-1 cells using transgenic (H2-c-fos) mice carrying the c-fos gene under the control of the constitutive H-2Kb promoter. The number of B-1b cells in the peritoneal cavity of H2-c-fos mice was 4-fold larger than that in control littermates. Although the numbers of total peritoneal B cells and B-1a cells were similar between them, the peritoneal B-2 cell number in H2-c-fos mice was reduced to 50% of control littermates, suggesting the effect of c-fos overexpression on a balance of B-1b and B-2 cells in a peritoneal cavity. Adoptive transfer experiments with hematopoietic stem cells of H2-c-fos and control mice into irradiated H2-c-fos mice demonstrated that the augmentation of B-1b cells is due to the c-fos effect in B cells and the effect on environment of the peritoneal cavity of H2-c-fos mice. When peritoneal B cells were cultured with LPS in the presence or absence of IL-4, cell proliferation of B-1b cells was the highest among these peritoneal B cell subsets, and the proliferation of H2-c-fos B-1b cells was 3-fold higher than that of control B-1b cells. This augmentation is due to the c-fos effect in B cells. IgG1 production of B-1b cells in these cultures was slightly higher than those of B-1a and peritoneal B-2 cells. Thus, the c-fos overexpression augments development of B-1b cells in a peritoneal cavity and proliferation of peritoneal B-1b cells to LPS.


Assuntos
Linfócitos B/imunologia , Genes fos/imunologia , Sistema Imunitário/crescimento & desenvolvimento , Transferência Adotiva , Animais , Formação de Anticorpos , Linfócitos B/citologia , Diferenciação Celular/imunologia , Proliferação de Células , Citometria de Fluxo , Genes fos/genética , Imunoglobulina G/análise , Imunoglobulina M/análise , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Transgênicos , Cavidade Peritoneal/fisiologia
10.
Naunyn Schmiedebergs Arch Pharmacol ; 370(1): 17-25, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15249992

RESUMO

We previously demonstrated an increase in Fos expression in the heart during morphine withdrawal. In the present study we examined the role of beta- and alpha-adrenoceptors in naloxone-precipitated increases in Fos expression in the heart. Dependence on morphine was induced by 7-day chronic subcutaneous implantation of six morphine pellets (75 mg). Morphine withdrawal was precipitated by administration of naloxone (5 mg/kg subcutaneously) on day 8. Using immunohistochemical staining of Fos, the present results indicate that morphine withdrawal induced marked Fos immunoreactivity (Fos-IR) within the cardiomyocyte nuclei. Moreover, Western blot analysis revealed a peak expression of c-fos in the right and left ventricles after naloxone-precipitated withdrawal in parallel with an increase in noradrenaline (NA) turnover. In the second study, the effects of the administration of adrenoceptor antagonists on withdrawal-induced Fos expression in the heart were studied. Pretreatment with the beta antagonist, propranolol (3 mg/kg intraperitoneally) or alpha1-adrenoceptor antagonist, prazosin (1 mg/kg intraperitoneally) did not block the marked Fos-IR or the hyperactivity of catecholaminergic neurons observed in the heart during withdrawal. However, pre-treatment with alpha2-adrenoceptor antagonist, yohimbine (1 mg/kg intraperitoneally), 20 min before naloxone administration to morphine-dependent rats antagonized Fos expression and the enhancement of NA turnover in the heart. Collectively, these results suggest that noradrenergic neurons in the heart are active during morphine withdrawal, and that activation of transcriptional responses mediated by Fos are dependent upon cardiac alpha2-adrenoceptor.


Assuntos
Genes fos/genética , Ventrículos do Coração/efeitos dos fármacos , Morfina/efeitos adversos , Receptores Adrenérgicos alfa 2/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/metabolismo , Antagonistas de Receptores Adrenérgicos alfa 2 , Animais , Western Blotting , Peso Corporal/efeitos dos fármacos , Esquema de Medicação , Quimioterapia Combinada , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Genes fos/efeitos dos fármacos , Genes fos/imunologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/ultraestrutura , Imuno-Histoquímica , Injeções Subcutâneas , Masculino , Morfina/administração & dosagem , Morfina/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/metabolismo , Naloxona/metabolismo , Naloxona/farmacologia , Normetanefrina/metabolismo , Prazosina/metabolismo , Prazosina/farmacologia , Propranolol/metabolismo , Propranolol/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa 2/genética , Síndrome de Abstinência a Substâncias/fisiopatologia , Fatores de Tempo , Ioimbina/metabolismo , Ioimbina/farmacologia
11.
J Neuroimmunol ; 142(1-2): 58-66, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14512164

RESUMO

Sublytic C5b-9 alters the molecular phenotype of myotubes by inhibiting muscle-specific gene expression. Here, we showed that C5b-9 induced c-fos mRNA and transcription. Using c-fos promoter-CAT constructs and electrophoretic mobility shift assay (EMSA), the minimal c-fos promoter activity was shown to increase within 30-min exposure to serum C5b-9, which also induced the binding of serum response factor (SRF), along with ternary complex factor (TCF) Elk1 and Sap1a to the serum response element. C5b-9 activated ERK1, which in turn activated Elk1 in myotubes. We propose that c-fos gene transcription associated with myotube dedifferentiation is induced by C5b-9 through ERK1-mediated assembly of serum response factor-ternary complex.


Assuntos
Complexo de Ataque à Membrana do Sistema Complemento/fisiologia , Regulação da Expressão Gênica/imunologia , Genes fos/imunologia , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Ativação Transcricional/imunologia , Adulto , Animais , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Linhagem Celular , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática/genética , Ativação Enzimática/imunologia , Humanos , Fator 1 de Ligação ao Facilitador Linfoide , Camundongos , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/enzimologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosforilação , Ligação Proteica/genética , Ligação Proteica/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Elementos de Resposta/imunologia , Fator de Resposta Sérica/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Fatores de Transcrição/metabolismo , Proteínas Elk-1 do Domínio ets
12.
J Immunol ; 169(2): 1007-13, 2002 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12097408

RESUMO

ICAM-1 and -2 are integrin-binding Ig superfamily adhesion molecules that are important for leukocyte transmigration across endothelial monolayers. ICAM-1 cross-linking is known to activate the small GTPase RhoA and induce stress fiber formation in endothelial cells, but ICAM-2 signaling has not been investigated. In this study, we compare ICAM-1 and ICAM-2 signaling and localization in HUVECs. Although ICAM-1 and ICAM-2 both localize with the actin-binding protein moesin in apical microvilli, only ICAM-1 colocalizes with moesin after cross-linking. Unlike ICAM-1, ICAM-2 does not activate RhoA or alter actin cytoskeletal organization. Interestingly, ICAM-1 stimulates transcription of c-fos, a known early response gene. In addition, it up-regulates rhoA expression, suggesting that it activates a positive feedback pathway after RhoA activation. These results indicate that in endothelial cells, ICAM-1, but not ICAM-2, rapidly stimulates signaling responses involving RhoA.


Assuntos
Antígenos CD/fisiologia , Moléculas de Adesão Celular/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Genes fos , Molécula 1 de Adesão Intercelular/fisiologia , Transcrição Gênica , Proteína rhoA de Ligação ao GTP/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Antígenos CD/imunologia , Antígenos CD/metabolismo , Moléculas de Adesão Celular/imunologia , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Reagentes de Ligações Cruzadas/metabolismo , Regulação da Expressão Gênica/imunologia , Genes fos/imunologia , Humanos , Soros Imunes/metabolismo , Soros Imunes/farmacologia , Molécula 1 de Adesão Intercelular/imunologia , Molécula 1 de Adesão Intercelular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Transcrição Gênica/imunologia , Proteína rhoA de Ligação ao GTP/biossíntese , Proteína rhoA de Ligação ao GTP/genética
13.
Neuroreport ; 13(4): 511-4, 2002 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-11930172

RESUMO

Protease-activated receptor-2 (PAR-2) in the sensory neurons may be involved in nociceptive processing. We attempted to detect and characterize specific expression of spinal Fos, a marker of nociception, in mast cell-depleted rats. Intraplantar (i.pl.) administration of not only the PAR-2 agonist SLIGRL-NH2, but also the control peptide LSIGRL-NH2, induced Fos expression in naive rats, whereas only the former specifically produced Fos expression in mast cell-depleted rats. This Fos expression was blocked by intrathecal DAMGO, a mu-opioid agonist, and, in part, by i.pl. calphostin C, a protein kinase C (PKC) inhibitor. Thus, specific expression of spinal Fos following peripheral PAR-2 activation is detectable in mast cell-depleted rats, suggesting activation of spinal nociceptive neurons, which is partially mediated by activation of PKC.


Assuntos
Genes fos/fisiologia , Mastócitos/metabolismo , Células do Corno Posterior/metabolismo , Receptores de Trombina/metabolismo , Medula Espinal/metabolismo , Animais , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Expressão Gênica/fisiologia , Genes fos/efeitos dos fármacos , Genes fos/imunologia , Masculino , Mastócitos/imunologia , Oligopeptídeos/farmacologia , Células do Corno Posterior/efeitos dos fármacos , Células do Corno Posterior/imunologia , Ratos , Ratos Wistar , Receptor PAR-2 , Receptores Opioides mu/agonistas , Receptores de Trombina/imunologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/imunologia
14.
Clin Orthop Relat Res ; (394): 271-7, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11795744

RESUMO

The effects of cooling on inflammatory response after injection of formalin in rats were examined by counting Fos-labeled cells in the dorsal horn of the spinal cord and evaluating swelling. A small amount of dilute formalin was injected into the right hindpaw of rats. The rats were divided into Cooling (-) and Cooling (+) groups and Fos-labeled cells in the spinal cord and paw volumes were compared between the two groups. In the Cooling (+) group, Fos-labeled cells were reduced significantly and the peak time of expression was delayed compared with the Cooling (-) group. Paw volumes were significantly smaller in the Cooling (+) group than in the Cooling (-) group. These results suggest that cooling therapy is effective by delaying the progress of inflammatory reactions and provides extra time for administration of analgesics or implementation of other clinical treatments.


Assuntos
Crioterapia/métodos , Edema/imunologia , Edema/terapia , Genes fos/imunologia , Inflamação/imunologia , Inflamação/terapia , Animais , Técnicas de Cultura , Modelos Animais de Doenças , Edema/induzido quimicamente , Feminino , Formaldeído , Imuno-Histoquímica , Inflamação/induzido quimicamente , Fotomicrografia , Ratos , Ratos Wistar , Valores de Referência , Medula Espinal/citologia
15.
J Immunol ; 167(2): 827-35, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11441089

RESUMO

Untransformed CD4(+) Th1 cells stimulated with Ag and APC demonstrated a dependence on B7- and CD28-mediated costimulatory signals for the expression and function of AP-1 proteins. The induction of transactivation by the c-fos gene regulator Elk-1 mirrored this requirement for TCR and CD28 signal integration. c-Jun N-terminal kinase (JNK) (but not extracellular signal-regulated kinase or p38) protein kinase activity was similarly inhibited by neutralizing anti-B7 mAbs. Blockade of JNK protein kinase activity with SB 202190 prevented both Elk-1 transactivation and c-Fos induction. These results identify a unique role for B7 costimulatory molecules and CD28 in the activation of JNK during Ag stimulation in Th1 cells, and suggest that JNK regulates Elk-1 transactivation at the c-fos gene to promote the formation of AP-1 complexes important to IL-2 gene expression.


Assuntos
Adjuvantes Imunológicos/fisiologia , Antígenos/imunologia , Antígenos CD28/fisiologia , Genes fos/imunologia , Ativação Linfocitária/imunologia , Proteínas Nucleares , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais/imunologia , Transcrição Gênica/imunologia , Animais , Apresentação de Antígeno , Antígeno B7-1/metabolismo , Antígeno B7-1/fisiologia , Antígenos CD28/metabolismo , Proteínas de Ligação a DNA/fisiologia , Elementos Facilitadores Genéticos/imunologia , Ativação Enzimática/imunologia , Regulação da Expressão Gênica/imunologia , Humanos , Interleucina-2/genética , Proteínas Quinases JNK Ativadas por Mitógeno , Células Jurkat , Ligantes , MAP Quinase Quinase 1 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Quinases de Proteína Quinase Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fatores de Transcrição NFATC , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/metabolismo , Células Th1/enzimologia , Células Th1/imunologia , Células Th1/metabolismo , Fator de Transcrição AP-1/biossíntese , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição AP-1/fisiologia , Fatores de Transcrição/fisiologia , Ativação Transcricional/imunologia , Proteínas Elk-1 do Domínio ets
16.
Cephalalgia ; 21(1): 46-52, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11298663

RESUMO

Clinical and preclinical studies suggest that 5-HT and nitric oxide (NO) mobilization within the trigeminovascular system is fundamental to the initiation of migraine attacks., e.g. m-chlorophenylpiperazine (m-CPP) and glyceryl trinitrate (GTN) induce headache in humans. 5-HT2B receptors are known to mediate NO-dependent vasorelaxation in peripheral blood vessels, raising the possibility that this receptor is implicated in the pathogenesis of the disease. Therefore, we measured the effects of 5-HT2B agonists (m-CPP or BW723C86) or GTN on trigeminal nerves by quantifying Fos expression in the rat TNC. m-CPP (0.1 mg/kg, i.v.) induced time-dependent elevations in Fos-LI in the rat TNC 2 h and 8 h after injection. In contrast, neither intravenous GTN (0.5 microg/kg per min, infused 20 min) nor BW723C86 (0.1 mg/kg, i.v.) increased Fos-LI at 2 h or 8 h after administration. These data are not consistent with the involvement of the 5-HT2B/2C receptors or NO in trigeminovascular activation, and by inference migraine, and suggest the contribution of some other unidentified pathway.


Assuntos
Genes fos/imunologia , Genes fos/fisiologia , Indóis/farmacologia , Transtornos de Enxaqueca/etiologia , Transtornos de Enxaqueca/fisiopatologia , Nitroglicerina/farmacologia , Piperazinas/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Tiofenos/farmacologia , Núcleo Inferior Caudal do Nervo Trigêmeo/fisiopatologia , Vasodilatadores/farmacologia , Animais , Óxido Nítrico/fisiologia , Ratos , Fatores de Tempo
17.
J Immunol ; 164(11): 5590-5, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10820233

RESUMO

In the process of positive selection, immature CD4+8+ double positive (DP) thymocytes expressing TCR reactive to self-MHC by appropriate avidity develop into mature thymocytes. Positive selection involves not only down-regulation of either CD4 or CD8 but also acquisition of immunocompetent potential such as cell proliferation and cytokine production. To understand the molecular basis for such functional maturation during the positive selection process, we examined whether nonselected DP, selected DP, and CD4+8- single positive thymocytes possess the activation potential for signaling pathways from mitogen-activated protein kinases (extracellular signal-regulated kinase and c-Jun N-terminal kinase) to AP-1. In response to stimulation, a marked induction of c-Fos protein expression as well as cell proliferation is detected only in CD4+8- single positive cells but not in selected and nonselected DP cells, though mitogen-activated protein kinase activities and c-fos transcripts are equally induced. In the presence of proteasome inhibitors, c-Fos protein became detectable in selected DP cells but still not in nonselected DP cells, suggesting that DP cells receiving positive selection signals acquire the capacity to translate the c-fos gene, but it may not be sufficiently high to overcome the degradation of c-Fos protein. These data indicate that the translating ability of the c-fos gene is up-regulated in the thymic positive selection process, from nonselected DP to CD4+8- single positive cells through positively selected DP cells. The distinguished responsiveness to stimulation in thymocytes with and without positive selection may be a result in part of the distinct regulation of the c-fos gene at the translational level.


Assuntos
Genes fos/imunologia , Biossíntese de Proteínas/imunologia , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Timo/citologia , Timo/imunologia , Animais , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Regulação da Expressão Gênica/imunologia , Genes jun/imunologia , Ativação Linfocitária/genética , Complexo Principal de Histocompatibilidade/genética , Complexo Principal de Histocompatibilidade/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Receptores de Antígenos de Linfócitos T/genética , Subpopulações de Linfócitos T/metabolismo , Timo/metabolismo , Transcrição Gênica/imunologia
18.
J Exp Med ; 190(3): 375-84, 1999 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-10430626

RESUMO

The Src family tyrosine kinases Lck and Fyn are critical for signaling via the T cell receptor. However, the exact mechanism of their activation is unknown. Recent crystal structures of Src kinases suggest that an important mechanism of kinase activation is via engagement of the Src homology (SH)3 domain by proline-containing sequences. To test this hypothesis, we identified several T cell membrane proteins that contain potential SH3 ligands. Here we demonstrate that Lck and Fyn can be activated by proline motifs in the CD28 and CD2 proteins, respectively. Supporting a role for Lck in CD28 signaling, we demonstrate that CD28 signaling in both transformed and primary T cells requires Lck as well as proline residues in CD28. These data suggest that Lck plays an essential role in CD28 costimulation.


Assuntos
Antígenos CD28/fisiologia , Ativação Linfocitária , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/imunologia , Prolina/fisiologia , Linfócitos T/imunologia , Domínios de Homologia de src/imunologia , Alanina/imunologia , Sequência de Aminoácidos , Substituição de Aminoácidos/imunologia , Animais , Antígenos CD28/genética , Antígenos CD28/metabolismo , Ativação Enzimática/imunologia , Regulação da Expressão Gênica/imunologia , Genes fos/imunologia , Humanos , Células Jurkat , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/genética , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/deficiência , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/genética , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Peptídeos/antagonistas & inibidores , Peptídeos/síntese química , Peptídeos/imunologia , Prolina/deficiência , Prolina/genética , Ligação Proteica/imunologia , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-fyn , Retroviridae/genética , Retroviridae/imunologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Acetato de Tetradecanoilforbol/farmacologia
19.
Brain Res Bull ; 48(2): 223-31, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10230714

RESUMO

Adaptation to infectious diseases or models of infectious diseases such as immune stimulation with exogenous administration of bacterial lipopolysaccharide (LPS) or cytokines involve complex autonomic, endocrine, and behavioral responses mediated by the central nervous system. The purpose of this study is to determine the neural pathways from the brainstem activating the central nucleus of the amygdala after LPS injections in rats. Fos immunohistochemistry was performed as a marker of neuronal activation in rats prepared with injections of the retrograde tracing agents Fluorogold or cholera toxin B subunit directed at the central nucleus of the amygdala, and subsequently treated with intravenous LPS. The dose of LPS was titrated to achieve behavioral suppression ("sickness behavior") and fever, while avoiding hypotension and shock. Low-dose LPS induced Fos in central amygdala afferent neurons in the periaqueductal gray, lateral parabrachial nucleus, and solitary nucleus, as indicated by neurons containing both Fos and retrograde tracing agent. The lateral parabrachial nucleus had approximately 10-fold higher numbers of double-labeled cells than the solitary nucleus and periaqueductal gray; 95% of the double-labeled neurons in the lateral parabrachial nucleus were located in the outer zone of the external lateral subnucleus. These results suggest that a prominent source of limbic activation from the brainstem after LPS involves a restricted subdivision of the lateral parabrachial nucleus.


Assuntos
Tonsila do Cerebelo/metabolismo , Tronco Encefálico/metabolismo , Endotoxinas/farmacologia , Escherichia coli/metabolismo , Genes fos/imunologia , Lipopolissacarídeos/farmacologia , Neurônios Aferentes/metabolismo , Tonsila do Cerebelo/citologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Tronco Encefálico/citologia , Frequência Cardíaca/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Neurônios Aferentes/citologia , Ratos , Ratos Sprague-Dawley
20.
Cytokine ; 11(1): 16-28, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10080875

RESUMO

A region between-3134 and -2729 bp upstream from the transcription site of the human pro-interleukin 1beta (proIL-1beta) gene was identified as an LPS-responsive enhancer element. In this study, the influence of the sequences located between -3134 and -2987 on the transcriptional activity of the proIL-1beta gene in LPS-stimulated Raw 264.7 cells was examined in detail. The results obtained by transient transfection of fos -CAT constructs that contained serial 5'-deletion mutations showed that the region between -3134 and -3059 appears to be required for the induction of transcription by LPS. Gel shift assay studies with synthetic oligonucleotides corresponding to partial sequences of the latter region and nuclear extracts from stimulated cells revealed specific protein binding sites between -3110 and -3090 and between -3079 and -3059. These specific bindings were time and LPS dose dependent. The results of supershift analysis using specific antibodies against transcription factors suggested that both binding complexes contained the NF-kappaB components p50 and p65, and did not contain other NF-kappaB proteins (p52, c-Rel, Rel B), AP-1 proteins (c-Fos, C-Jun), CREB or C/EBPbeta (NF-IL6). Mutation of either of the putative NF-kappaB-binding sites in the enhancer element decreased the LPS-stimulated transcriptional activity. These data indicated that two NF-kappaB-binding sites, which are located between -3134 and -3059, are critical for the activation of proIL-1beta gene transcription.


Assuntos
Regulação da Expressão Gênica , Interleucina-1/genética , NF-kappa B/fisiologia , Precursores de Proteínas/genética , Animais , Ligação Competitiva , Proteínas Estimuladoras de Ligação a CCAAT , Linhagem Celular , Cloranfenicol O-Acetiltransferase/análise , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/imunologia , Proteínas de Ligação a DNA/imunologia , Eletroforese em Gel de Poliacrilamida , Elementos Facilitadores Genéticos , Genes fos/imunologia , Genes jun/imunologia , Humanos , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/fisiologia , Camundongos , Modelos Biológicos , Monócitos/fisiologia , Mutagênese , Proteínas Nucleares/imunologia , Oligonucleotídeos , Oncogenes/imunologia , Plasmídeos , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica/fisiologia , Transfecção
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