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1.
Immune Netw ; 18(5): e35, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30402330

RESUMO

Aryl hydrocarbon receptor (AhR) regulates both innate and adaptive immune responses by sensing a variety of small synthetic and natural chemicals, which act as its ligands. AhR, which is expressed in dendritic cells (DCs), regulates the differentiation of DCs. However, effects of AhR on the differentiation of DCs are variable due to the heterogeneity of DCs in cell surface marker expression, anatomical location, and functional responses. The plasmacytoid DCs (pDCs), one of DC subsets, not only induce innate as well as adaptive immune responses by secreting type I interferons and pro-inflammatory cytokines, but also induce IL-10 producing regulatory T cell or anergy or deletion of antigen-specific T cells. We showed here that AhR ligands indoxyl 3-sulfate (I3S) and indole-3-carbinol (I3C) inhibited the development of pDCs derived from bone marrow (BM) precursors induced by FMS-like tyrosine kinase 3 ligand (Flt3L). I3S and I3C downregulated the expression of signal transducer and activator of transcription 3 (STAT3) and E2-2 (Tcf4). In mice orally treated with I3S and I3C, oral tolerance to dinitrofluorobenzene was impaired and the proportion of CD11c+B220+ cells in mesenteric lymph nodes was reduced. These data demonstrate that AhR negatively regulates the development of pDCs from BM precursors induced by Flt3L, probably via repressing the expression of STAT3.

2.
Mol Cells ; 41(4): 290-300, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29562732

RESUMO

Using an in vitro model of intestinal organoids derived from intestinal crypts, we examined effects of indole-3-carbinol (I3C), a phytochemical that has anticancer and aryl hydrocarbon receptor (AhR)-activating abilities and thus is sold as a dietary supplement, on the development of intestinal organoids and investigated the underlying mechanisms. I3C inhibited the in vitro development of mouse intestinal organoids. Addition of α-naphthoflavone, an AhR antagonist or AhR siRNA transfection, suppressed I3C function, suggesting that I3C-mediated interference with organoid development is AhR-dependent. I3C increased the expression of Muc2 and lysozyme, lineage-specific genes for goblet cells and Paneth cells, respectively, but inhibits the expression of IAP, a marker gene for enterocytes. In the intestines of mice treated with I3C, the number of goblet cells was reduced, but the number of Paneth cells and the depth and length of crypts and villi were not changed. I3C increased the level of active nonphosphorylated ß-catenin, but suppressed the Notch signal. As a result, expression of Hes1, a Notch target gene and a transcriptional repressor that plays a key role in enterocyte differentiation, was reduced, whereas expression of Math1, involved in the differentiation of secretory lineages, was increased. These results provide direct evidence for the role of AhR in the regulation of the development of intestinal stem cells and indicate that such regulation is likely mediated by regulation of Wnt and Notch signals.


Assuntos
Indóis/metabolismo , Receptores Notch/genética , Via de Sinalização Wnt/genética , Animais , Diferenciação Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
3.
Oncol Rep ; 39(4): 1930-1938, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29436668

RESUMO

Various amino acids regulate cell growth and differentiation. In the present study, we examined the ability of HT-29 cells to differentiate into goblet cells in RPMI and DMEM which are largely different in the amounts of numerous amino acids. Most of the HT-29 cells differentiated into goblet cells downregulating the stem cell marker Lgr5 when cultured in DMEM, but remained undifferentiated in RPMI. The goblet cell differentiation in DMEM was inhibited by 1-methyl-tryptophan (1-MT), an inhibitor of indoleamine 2,3 dioxygenase-1 which is the initial enzyme in tryptophan metabolism along the kynurenine (KN) pathway, whereas tryptophan and KN induced goblet cell differentiation in RPMI. The levels of Notch1 and its activation product Notch intracytoplasmic domain in HT-29 cells were lower in DMEM than those in RPMI and were increased by 1-MT in both media. HT-29 cells grown in both media expressed ß-catenin at the same level on day 2 when goblet cell differentiation was not observed. ß-catenin expression, which was increased by 1-MT in both media, was decreased by KN. DMEM reduced Hes1 expression while enhancing Hath1 expression. Finally, aryl hydrocarbon receptor (AhR) activation moderately induced goblet cell differentiation. Our results suggest that KN promotes goblet cell differentiation by regulating Wnt, Notch, and AhR signals and expression of Hes1 and Hath1.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Cinurenina/administração & dosagem , Fatores de Transcrição HES-1/genética , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Caliciformes/efeitos dos fármacos , Células Caliciformes/patologia , Células HT29 , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Receptor Notch1/genética , Receptores de Hidrocarboneto Arílico/genética , Triptofano/análogos & derivados , Triptofano/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/genética
4.
Environ Toxicol Pharmacol ; 43: 44-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26950395

RESUMO

The intestinal epithelium plays a central role in immune homeostasis in the intestine. AhR, a ligand-activated transcription factor, plays an important role in diverse physiological processes. The intestines are exposed to various exogenous and endogenous AhR ligands. Thus, AhR may regulate the intestinal homeostasis, directly acting on the development of intestinal epithelial cells (IEC). In this study, we demonstrated that 6-formylindolo[3,2-b]carbazole (FICZ) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibited the in vitro development of mouse intestinal organoids. The number of Paneth cells in the small intestine and the depth of crypts of the small and large intestines were reduced in mice administrated with FICZ. Immunohistochemical and flow cytometric assays revealed that AhR was highly expressed in Lgr5(+) stem cells. FICZ inhibited Wnt signaling lowering the level of ß-catenin protein. Gene expression analyses demonstrated that FICZ increased expression of Lgr5, Math1, BMP4, and Indian Hedgehog while inhibiting that of Lgr4.


Assuntos
Carbazóis/toxicidade , Células Epiteliais/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Células Epiteliais/fisiologia , Inibidores do Crescimento/toxicidade , Camundongos
5.
Immunol Lett ; 165(1): 10-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25794633

RESUMO

Toll-like receptors (TLRs) recognize a wide range of pathogen-associated molecular patterns (PAMP) and are preferentially expressed in innate immune cells. TLR-mediated activation of these cells activates the adaptive immune system. However, it has become clear that TLRs are not only expressed but also functionally active in CD4 T cells. The intestines are continuously exposed to TLR ligands, including lipopolysaccharide (LPS), a TLR4 ligand, and TLR4 is expressed higher in Th17 cells than Th1 and Th2 cells. In addition, development of Th17 cells in the gut mucosa is more dependent on gut microbiota than Th1, Th2, and Treg. Thus, we examined whether LPS directly regulates Th17 differentiation. LPS directly stimulated Th17 differentiation in vitro. In Th17 cells, LPS increased phosphorylation of NF-κB1, resulting in an increase of p50, the processed form of NF-κB1, whereas it decreased phosphorylation of RelB, leading to the up-regulation of RelB. Subcutaneous injection of LPS increased the frequency of IL-17 producing cells in inguinal lymph nodes, worsening experimental autoimmune encephalomyelitis (EAE). Additionally, expression of TLR1, TLR2, TLR4, and TLR5 was reduced upon T cell activation and LPS showed modest effect on TLR4 expression. These findings provide the first evidence that TLR4 activation directly regulate Th17 differentiation.


Assuntos
Lipopolissacarídeos/imunologia , Subunidade p50 de NF-kappa B/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Fator de Transcrição RelB/metabolismo , Animais , Diferenciação Celular , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Interleucina-17/biossíntese , Linfonodos/imunologia , Linfonodos/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Camundongos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fosforilação , Células Th17/citologia , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
6.
Immune Netw ; 15(6): 278-90, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26770182

RESUMO

The intestinal immune system maintains oral tolerance to harmless antigens or nutrients. One mechanism of oral tolerance is mediated by regulatory T cell (Treg)s, of which differentiation is regulated by a subset of dendritic cell (DC)s, primarily CD103(+) DCs. The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, plays an important role in regulating immunity. The intestines are exposed to various AhR ligands, including endogenous metabolites and phytochemicals. It was previously reported that AhR activation induced tolerogenic DCs in mice or in cultures of bone marrow-derived DCs. However, given the variety of tolerogenic DCs, which type of tolerogenic DCs is regulated by AhR remains unknown. In this study, we found that AhR ligand 3,3'-diindolylmethane (DIM) inhibited the development of CD103(+) DCs from mouse bone marrow cells stimulated with Flt3L and GM-CSF. DIM interfered with phosphorylation of STAT3 and STAT5 inhibiting the expression of genes, including Id2, E2-2, IDO-1, and Aldh1a2, which are associated with DC differentiation and functions. Finally, DIM suppressed the ability of CD103(+) DCs to induce Foxp3(+) Tregs.

7.
Oncotarget ; 5(19): 9065-78, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25238053

RESUMO

Liposarcoma is one of the most common histologic types of soft tissue sarcoma and is frequently an aggressive cancer with poor outcome. Hence, alternative approaches other than surgical excision are necessary to improve treatment of well-differentiated/dedifferentiated liposarcoma (WDLPS/DDLPS). For this reason, we performed a two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization-time of flight mass spectrometry/mass spectrometry (MALDI-TOF/MS) analysis to identify new factors for WDLPS and DDLPS. Among the selected candidate proteins, gankyrin, known to be an oncoprotein, showed a significantly high level of expression pattern and inversely low expression of p53/p21 in WDLPS and DDLPS tissues, suggesting possible utility as a new predictive factor. Moreover, inhibition of gankyrin not only led to reduction of in vitro cell growth ability including cell proliferation, colony-formation, and migration, but also in vivo DDLPS cell tumorigenesis, perhaps via downregulation of the p53 tumor suppressor gene and its p21 target and also reduction of AKT/mTOR signal activation. This study identifies gankyrin, for the first time, as new potential predictive and oncogenic factor of WDLPS and DDLPS, suggesting the potential for service as a future LPS therapeutic approach.


Assuntos
Biomarcadores Tumorais/genética , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Lipossarcoma/patologia , Complexo de Endopeptidases do Proteassoma/genética , Proteínas Proto-Oncogênicas/genética , Proteína Supressora de Tumor p53/biossíntese , Animais , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo , Células HEK293 , Humanos , Lipossarcoma/tratamento farmacológico , Camundongos , Prognóstico , Complexo de Endopeptidases do Proteassoma/biossíntese , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/biossíntese , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Serina-Treonina Quinases TOR/biossíntese , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Toxicol Lett ; 225(1): 130-8, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24291743

RESUMO

Immune system dysfunctions including the increased Th1/Th2 ratio are common in chronic kidney disease (CKD) patients, and a wide variety of skin diseases including Th1-mediated uremic pruritis are associated with CKD. Although there are more than 90 uremic toxins reported, it is yet to be known which uremic solute is associated with the unbalanced Th1/Th2 ratio and how it works. Indoxyl 3-sulfate (I3S), one of uremic toxins and a potent aryl hydrocarbon receptor (AhR) ligand, accumulates in blood and tissues, increasing up to 81.04 µM in CKD patients, compared with 1.03 µM in healthy subjects. I3S activates NF-κB and AhR. Thus, we investigated roles of I3S in the differentiation of Th1 and Th2 cells. I3S inhibited Th2 differentiation but showed little or no effect on Th1 differentiation. I3S suppressed Th2-mediated ovalbumin-induced allergic asthma in mice and decreased the frequency of IL-4 producing CD4 T cells in the lungs. I3S inhibited phosphorylation of STAT5 and STAT6, transcription factors associated with Th2 differentiation. Effects of I3S on Th2 differentiation were suppressed by α-naphtoflavone, an AhR antagonist, indicating that I3S regulates Th2 differentiation AhR-dependently.


Assuntos
Asma/metabolismo , Diferenciação Celular , Indicã/metabolismo , Células Th1/metabolismo , Células Th2/metabolismo , Uremia/metabolismo , Animais , Asma/induzido quimicamente , Asma/imunologia , Asma/prevenção & controle , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Benzoflavonas/farmacologia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Imunoglobulina E/sangue , Interleucina-4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina , Fosforilação , Eosinofilia Pulmonar/imunologia , Eosinofilia Pulmonar/metabolismo , Eosinofilia Pulmonar/prevenção & controle , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/metabolismo , Fator de Transcrição STAT5/metabolismo , Fator de Transcrição STAT6/metabolismo , Células Th1/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Uremia/imunologia
9.
Toxicol Lett ; 220(2): 109-17, 2013 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-23639249

RESUMO

Although AhR activation regulates CD4T cell differentiation, how it works has yet to be elucidated. In the present study, using in vitro Th17 differentiation model, we examined effects of AhR activation by indoxyl 3-sulfate (I3S), a uremic toxin, on Th17 differentiation and investigated underlying mechanisms. I3S increased expression of RORγt, the master transcription factor for Th17 differentiation, and stimulated Th17 differentiation, in a comparative manner as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a prototypical AhR ligand. Activation of STAT3, which is phosphorylated by the IL-6 signaling pathways and thus is necessary for Th17 differentiation, was strongly stimulated by I3S and TCDD. Phosphorylation of c-Src, which was shown to be activated by AhR ligands, was also increased by I3S and TCDD, and blocking of c-Src activity by 4-amino-5-(4-chlorophenyl)-7-(t-butyl) pyrazolo[3,4-d]pyrimidine (PP2) inhibited phosphorylation of both c-Src and STAT3, raising a possibility that stimulatory activities of I3S and TCDD on Th17 differentiation could be exerted via increased phosphorylation of c-Src, which in turn stimulates STAT3 activation. Finally, we found that I3S worsened experimental autoimmune encephalomyelitis (EAE), which is primarily mediated by Th17 cells, enhancing the frequency of IL-17-producing cells in draining lymph nodes.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Indicã/farmacologia , Fator de Transcrição STAT3/metabolismo , Células Th17/efeitos dos fármacos , Quinases da Família src/metabolismo , Animais , Proteína Tirosina Quinase CSK , Diferenciação Celular/efeitos dos fármacos , Encefalomielite Autoimune Experimental/induzido quimicamente , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacologia , Células Th17/citologia , Células Th17/imunologia , Células Th17/metabolismo
10.
Environ Toxicol Pharmacol ; 34(3): 858-68, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22981438

RESUMO

To study mechanisms underlying differential effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and benzo(a)pyrene (B(a)P) on thymocyte differentiation, we examined effects of AhR ligands on the differentiation of DPK cells, a CD4(+)CD8(+) thymic lymphoma cell line which can differentiate into CD4(+)CD8(-) thymocytes. In contrast to TCDD, which inhibited the differentiation, B(a)P showed little effect. Antigen-mediated up-regulation of S100A4, S100A6, galectin-1, and TRAF5-like protein was remarkably suppressed by TCDD, but slightly by B(a)P. Immunoprecipitation using anti-ARNT Ab revealed that SDS3, a component of the Sin3/HDAC repressor complex, was associated with ARNT only when DPK cells were incubated with TCDD. Expression of cKrox S100A4 was derepressed when SDS3 protein was reduced. These results indicate that although it is generally known that many AhR ligands such as TCDD and B(a)P function mainly by the AhR/ARNT complex, ligand-specific interaction between SDS3 and ARNT exerts differential effects on the expression of genes associated with thymocyte differentiation.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Regulação da Expressão Gênica , Receptores de Hidrocarboneto Arílico/metabolismo , Proteínas Repressoras/metabolismo , Timócitos/fisiologia , Antígenos CD4/metabolismo , Antígenos CD8/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA , Galectina 1/metabolismo , Humanos , Ligantes , Ativação Linfocitária/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Proteína A4 de Ligação a Cálcio da Família S100 , Proteínas S100 , Regulação para Cima
11.
Int Immunopharmacol ; 13(4): 377-85, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22561122

RESUMO

Most studies about functions of aryl hydrocarbon receptor (AhR) in the pathogenesis of asthma have been carried out with non-physiological industrial by-products such as 2,3,7,8-tetrachlorodibenzo-p-dioxin and benzo(a)pyrene. In the present study, effects of 6-formylindolo[3,2-b]carbazole (FICZ), a tryptophan photoproduct postulated as a candidate physiological ligand of AhR, on the pathogenesis of asthma were examined and then underlying mechanisms of its immumodulatory effects were investigated. FICZ significantly reduced pulmonary eosinophilia and Th2 cytokine expression in the lungs. Flow cytometric analysis of mediastinal lymph nodes showed that IL-4 producing cells decreased in FICZ-treated mice compared with PBS control. Next, effects of FICZ on in vitro Th2 differentiation and expression of the Th2 transcription factor GATA-3 were examined. CD4+ T cells were isolated from the spleen and incubated under the Th2 differentiation conditions. FICZ inhibited both Th2 differentiation and the expression of GATA-3. Finally, activation of STAT6, which is necessary for Th2 differentiation, was inhibited by FICZ.


Assuntos
Asma/tratamento farmacológico , Carbazóis/administração & dosagem , Citocinas/metabolismo , Eosinofilia Pulmonar/tratamento farmacológico , Células Th2/imunologia , Animais , Antialérgicos/administração & dosagem , Antialérgicos/efeitos adversos , Asma/complicações , Asma/imunologia , Carbazóis/efeitos adversos , Carbazóis/farmacologia , Células Cultivadas , Citocinas/genética , Modelos Animais de Doenças , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia de Imunossupressão , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Eosinofilia Pulmonar/imunologia , Receptores de Hidrocarboneto Arílico/agonistas , Células Th2/efeitos dos fármacos , Triptofano/metabolismo
12.
Int Immunopharmacol ; 10(10): 1242-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20637839

RESUMO

Asthma is a chronic inflammatory disease of the airways characterized by reversible airway obstruction, airway hyperreactivity, and remodeling of the airways. Chlorogenic acid (CGA), an ester of caffeic acid with quinic acid, is one of the most abundant polyphenol compounds in various agricultural products. CGA shows various biological properties, such as anti-oxidant, anti-viral, anti-carcinogenic and anti-inflammatory activities. We investigated suppressive effects of CGA on ovalbumin (OVA)-induced allergic asthma in mice and underlying mechanisms of them. CGA significantly reduced pulmonary eosinophilia and expression of IL-4, IL-5 and TNF-α in the lung as well as the serum levels of total and OVA-specific IgE, while CGA enhanced those of total and OVA-specific IgG3, of which isotype switching is down-regulated by IL-4. In vitro IgE production from LPS/IL-4-stimulated splenocytes was remarkably reduced by CGA, while that of IgG3 was enhanced. The Cε germ line transcription, which is necessary for IL-4 mediated IgE isotype switching, was reduced by CGA in LPS/IL-4-stimulated splenocytes. IgE isotype switching is mediated via several transduction pathways, activating several molecules including STAT-6, NF-κB, ERK1/2, and JNK. Among the molecules, which were activated by IL-4/LPS, activation of STAT-6 and JNK was inhibited by CGA.


Assuntos
Asma/induzido quimicamente , Ácido Clorogênico/uso terapêutico , Citocinas/metabolismo , Imunoglobulina E/metabolismo , Eosinofilia Pulmonar/prevenção & controle , Fator de Transcrição STAT6/metabolismo , Animais , Artemisia/química , Asma/tratamento farmacológico , Asma/imunologia , Ácido Clorogênico/química , Hipersensibilidade/tratamento farmacológico , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/toxicidade , Fator de Transcrição STAT6/genética , Células Th2/metabolismo
13.
Toxicol Lett ; 196(2): 87-94, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20385220

RESUMO

When pregnant mice were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the average time to eye opening in the offspring was shortened by about a day. How acceleration of eye opening by TCDD occurs remains unknown. To reveal the underlying mechanisms of the accelerated eye opening, pregnant mice were intraperitoneally injected with corn oil or TCDD at GD (gestation day) 11, and tissues around the eye of neonatal mice were subject to proteome analysis and RT-PCR. Upon TCDD administration, translationally controlled tumor protein (TCTP) and 60S acidic ribosomal protein p2 (RLA2) were reduced, while stathmin 1(STMN1) was increased, at both protein and mRNA levels. One hypothetical mechanism for eye opening is the proliferation of corneal epithelial cells before eye opening. STMN1, but not TCTP and RLA2, was up-regulated in immortalized human corneal epithelial cells (HCE-T) by TCDD, which promoted proliferation of HCE-T probably by accelerating the G1/S transition. Down-regulation of STMN1 by the antisense oligonucleotide technology inhibited proliferation of HCE-T, suggesting that STMN1, of which expression is enhanced by TCDD, may be involved in accelerated eye opening, probably by stimulating proliferation of corneal epithelial cells.


Assuntos
Poluentes Ambientais/farmacologia , Epitélio Corneano/efeitos dos fármacos , Olho/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Estatmina/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Benzo(a)pireno/farmacologia , Biomarcadores Tumorais/metabolismo , Western Blotting , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Poluentes Ambientais/administração & dosagem , Epitélio Corneano/metabolismo , Olho/crescimento & desenvolvimento , Olho/metabolismo , Feminino , Idade Gestacional , Humanos , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos BALB C , Oligonucleotídeos Antissenso/metabolismo , Fosfoproteínas/metabolismo , Dibenzodioxinas Policloradas/administração & dosagem , Gravidez , Proteômica/métodos , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Ribossômicas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Estatmina/genética , Transfecção , Proteína Tumoral 1 Controlada por Tradução , Regulação para Cima
14.
Environ Toxicol ; 25(6): 533-44, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19459145

RESUMO

Embryo sacs of the Korean salamander, Hynobius leechii, were collected from nine farmlands in Gyeongsangnam-Do, Korea, in early spring of 2002 and 2004. The variations in the number of embryos within each embryo sac and the mortality and abnormality rates among the embryos were investigated. We also analyzed the patterns of spontaneous embryonic malformations and the residual chemicals in the soil of the habitats using multiple-residue GC/MS. A total of 79,195 embryos were obtained from 1933 embryo sacs. There were regional variations in the length of individual embryo sacs and the number of embryos in each. The longest embryo sac averaged by region measured 20.67 cm ± 3.51 and was obtained from 2-Banseong in 2002. Of the embryos collected, 13.71% either died or stopped developing, and 3.54% of the hatched embryos developed abnormally; the latter were classified according to the patterns of malformation. External gill dysplasia was the most frequent malformation, and caudal dysplasia, abdominal blisters, and dysplasia of the fin were also observed frequently. Histopathological analysis showed neural tube abnormalities, acrania, curved notochords, thyroid teratoma, and various other kinds of endodermal developmental abnormalities. In the analysis of the residual pesticides in the soil, carbofuran, endosulfan-sulfate, and endosulfan-ß were detected in the regions with high mortality and malformation rates. These results indicate that various agricultural chemicals and other unknown factors may cause the aforementioned forms of spontaneous malformations in the embryos of Hynobius leechii.


Assuntos
Praguicidas/toxicidade , Urodelos/anormalidades , Urodelos/embriologia , Compostos de Anilina/toxicidade , Animais , Carbofurano/toxicidade , Dicofol/toxicidade , Endossulfano/toxicidade , Cromatografia Gasosa-Espectrometria de Massas , Nitrilas/toxicidade , Compostos Organotiofosforados/toxicidade , República da Coreia , Urodelos/anatomia & histologia
15.
Toxicol Lett ; 187(3): 157-63, 2009 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-19429259

RESUMO

To study the mechanisms underlying the linage commitment of CD4+CD8+ thymocytes and the skewed differentiation of CD4+CD8+ into CD4-CD8+ thymocytes induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), we stimulated with antigen DPK cells, a CD4+CD8+ thymic lymphoma cell line which can differentiate into CD4+CD8- thymocytes and performed a comparative proteomic analysis of DPK cells stimulated with antigen or not. Among the 10 up-regulated or induced proteins upon antigenic stimulation, S100A4, S100A6, and galectin-1 were highly up-regulated. Kinetic studies revealed that expression of S100A4, S100A6, and galectin-1 was dramatically increased as early as 10min after antigen stimulation, similar to that of cKrox and Runx3, transcription factors intimately associated with the lineage commitment. Among four thymocyte subpopulations of the thymus examined, S100A4, S1006, and galectin-1 were most prominently expressed in CD4+CD8+ thymocytes, but not at all in CD4-CD8+ and CD4-CD8- thymocytes. In the spleen, expression of S100A4, S1006, and galectin-1 was greater in CD4 than in CD8 splenocytes. When TCDD was added to antigen-stimulated DPK cells, antigen-induced up-regulation of S100A4, S1006, and galectin-1 were remarkably inhibited, probably partly accounting for the skewed differentiation of CD4+CD8+ into CD4-CD8+ thymocytes induced by TCDD.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Proteínas de Ciclo Celular/biossíntese , Dioxinas/toxicidade , Galectina 1/biossíntese , Proteínas S100/biossíntese , Timo/efeitos dos fármacos , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Ciclo Celular/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Eletroforese em Gel Bidimensional , Galectina 1/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteômica/métodos , Proteína A6 Ligante de Cálcio S100 , Proteína A4 de Ligação a Cálcio da Família S100 , Proteínas S100/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Timo/citologia , Timo/metabolismo , Regulação para Cima/efeitos dos fármacos
16.
Immunol Lett ; 122(1): 76-83, 2009 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-19111575

RESUMO

To identify asthma-susceptibility genes, we did proteome analyses of the lung from control and ovalbumin-sensitized BALB/c mice. Among the 6 up-regulated proteins is alpha(1)-protease inhibitor (alpha(1)-PI) type 2, which is a member of the serine protease inhibitor superfamily of protease inhibitors that participate in a variety of physiological functions, including extracellular matrix remodeling and inflammation. The up-regulated expression of alpha(1)-PI type 2 was confirmed by real-time PCR. Then we examined mRNA expression of five members of the alpha(1)-PI family genes (alpha(1)-PI types 1-5) in several organs of BALB/c mice and found that in addition to the liver, all the organs tested also expressed different isoforms of alpha(1)-PI in a tissue-specific manner, albeit to a lesser extent compared with the liver. When a similar study was performed with C57BL/6 mice, which have been shown to be more susceptible to ovalbumin-induced asthma than BALB/c mice, a pair of remarkable differences between the mouse strains were revealed: (1) the magnitude of alpha(1)-PI type 2 mRNA in all the organs was much higher in BALB/c than in C57BL/6 mice and (2) alpha(1)-PI type 2 is the only isoform expressed in the lung of BALB/c, but not of C57BL/c mice. Using the antisense oligonucleotide technology to specifically down-regulate expression of alpha(1)-PI type 2, we demonstrated that pulmonary infiltration of eosinophils was significantly increased by intranasal administration of alpha(1)-PI type 2 antisense oligonucleotides in OVA-sensitized mice, suggesting that alpha(1)-PI type 2 may suppress the progress of asthma, probably by acting on neutrophil elastase, which can produce many of the pathological features of asthma.


Assuntos
Movimento Celular/genética , Eosinófilos/metabolismo , Eosinofilia Pulmonar/imunologia , alfa 1-Antitripsina/metabolismo , Administração Intranasal , Animais , Movimento Celular/imunologia , Eosinófilos/imunologia , Eosinófilos/patologia , Expressão Gênica , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/genética , Especificidade de Órgãos , Ovalbumina/imunologia , Proteômica , Eosinofilia Pulmonar/terapia , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , alfa 1-Antitripsina/química , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/imunologia
17.
Toxicol Lett ; 180(3): 189-95, 2008 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-18602973

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) was reported to skew the lineage commitment of thymocytes toward CD4(-)CD8+ T (CD8 T) cells. However, the underlying mechanisms are not known. In the present study, we first demonstrated that the expression of transcription regulatory factors such as cKrox and Runx3, which have been shown to be intimately associated with the commitment of CD4+CD8+ double-positive (DP) to CD4 or CD8 single-positive (SP) thymocyes, was down-regulated by TCDD in CD4 SP thymocytes, but up-regulated in DP, CD4+CD8+ double-negative (DN), and CD8 SP thymocytes. Then, we found that TCDD inhibited the differentiation of DPK cells, an immature CD4+CD8+ lymphoma cell line, into CD4+CD8(-) T cells, as well as the expression of cKrox and Runx3 upon antigen stimulation. Co-treatment with the AhR antagonist alpha-naphthoflavone did not completely block the inhibitory action of TCDD on DPK differentiation and the expression of cKrox and Runx3 in DPK cells, suggesting that the immunomodulatory abilities of TCDD are produced, at least in part, independently of the AhR pathway in DPK cells. Our findings could help in understanding the regulatory mechanisms of TCDD on thymocyte development, in particular on the skewed differentiation of DP into CD8 SP thymocytes.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linhagem da Célula/genética , Subunidade alfa 3 de Fator de Ligação ao Core/biossíntese , Proteínas de Ligação a DNA/biossíntese , Poluentes Ambientais/toxicidade , Dibenzodioxinas Policloradas/farmacologia , Fatores de Transcrição/biossíntese , Animais , Benzoflavonas/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Int Immunopharmacol ; 8(4): 534-41, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18328444

RESUMO

Dendritic cells (DCs) are the most potent antigen-presenting cells (APC) particularly important in the initiation of primary T cell-mediated immune responses. Thus, inhibition of the differentiation and function of DC could lead to the suppression of immunological hyperresponsiveness. Artemisia iwayomogi, a member of the Compositae, is a perennial herb easily found in Korea and has been used as a traditional anti-inflammatory medicine. We investigated suppressive effects of carbohydrate fraction 1 from the water extracts of A. iwayomogi (AIP1) on the differentiation and function of bone marrow-derived dendritic cells. Bone marrow cells were cultured in the presence of granulocyte monocyte-colony stimulating factor (GM-CSF) and interleukin (IL)-4 for 6-7 days. Then, non-adherent cells were harvested for subsequent analyses. Percentage(s) of CD11c+ MHC II+ cell population(s) mostly composed of immature or mature DC and the allogeneic T cell stimulating ability of the cells were reduced by AIP1. Proteomic analyses along with RT-PCR revealed that expressions of several proteins including TNF receptor-associated factor (TRAF) 5-like protein, pyruvate kinase M2 (PKM2), and coactosin-like protein 1 (CLP1) were down-regulated upon AIP1 treatment.


Assuntos
Artemisia/química , Carboidratos/farmacologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Extratos Vegetais/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Interleucina-4/imunologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/isolamento & purificação , Proteoma/metabolismo , Linfócitos T/imunologia
19.
Environ Toxicol ; 23(1): 131-44, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18214921

RESUMO

We investigated the toxic effects of carbendazim and n-butyl isocyanate (BIC), metabolites of the fungicide benomyl, on development in the African clawed frog, Xenopus laevis. To test the toxic effects, frog embryo teratogenesis assays using Xenopus were performed. Embryos were exposed to various concentrations of carbendazim (0-7 microM) and BIC (0-0.2 microM). LC(100) for carbendazim and BIC were 7 and 0.2 microM, respectively, and the corresponding LC(50), determined by probit analysis, were 5.606 and 0.135 microM. Exposure to carbendazim concentrations > or = 3 microM and BIC concentrations > or = 0.1 microM resulted in 10 different types of severe external malformation. Histological examinations revealed dysplasia of the brain, eyes, intestine, and somatic muscle, and swelling of the pronephric ducts. These phenomena were common in both test groups. The tissue-specific toxic effects were investigated with an animal cap assay. Neural tissues are normally induced at a high frequency by activin A, however, the induction of neural tissues was strongly inhibited by the addition of carbendazim. Conversely, the addition of BIC resulted in weak inhibition of neural tissues. Electron micrographs of animal cap explants revealed degeneration of cell junctions in the carbendazim-treated group, but not in the BIC-treated group. Numerous residual yolk platelets and mitochondrial degeneration were commonly observed in both test groups. The gene expression of cultivated animal cap explants was investigated by reverse transcriptase-polymerase chain reaction and revealed that expression of the neural-specific marker neural cell adhesion molecule was more strongly inhibited in the carbendazim-treated group than in the BIC-treated group.


Assuntos
Benomilo/toxicidade , Exposição Ambiental , Fungicidas Industriais/toxicidade , Xenopus laevis/embriologia , Animais , Benzimidazóis/toxicidade , Carbamatos/toxicidade , Primers do DNA , Embrião não Mamífero/efeitos dos fármacos , Isocianatos/toxicidade , Dose Letal Mediana , Sistema Nervoso/embriologia , Sistema Nervoso/metabolismo , Sistema Nervoso/ultraestrutura , RNA/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Xenopus laevis/genética , Xenopus laevis/crescimento & desenvolvimento
20.
Int Immunopharmacol ; 8(1): 117-25, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18068107

RESUMO

Asthma is a chronic inflammatory disease of the airways characterized by reversible airway obstruction, airway hyperreactivity, and remodeling of the airways. The incidence of asthma is on the rise despite ongoing intensive asthma research. Artemisia iwayomogi, a member of the Compositae, is a perennial herb easily found around Korea and has been used as a traditional anti-inflammatory medicine in liver diseases. We investigated suppressive effects of AIP1, a water-soluble carbohydrate fraction from A. iwayomogi on ovalbumin-induced allergic asthma in BALB/c mice and studied the possible mechanisms of its anti-allergic action. AIP1 significantly reduced pulmonary eosinophilia and Th2 cytokine expression in the lungs as well as serum IgE levels. Flow cytometric analysis of lung-infiltrating cells showed that the surface levels of CD11c and MHC II in CD11c+MHC II+ cells, potent dendritic cells, decreased in animals treated with AIP1. Expression of TNF-alpha, one of several proinflammatory cytokines released into the airway during episodes of asthma, was down-regulated by AIP1 injection, suggesting that reduced expression of TNF-alpha could account for the suppression of pulmonary eosinophilia and Th2-type cytokine production by AIP1.


Assuntos
Artemisia/imunologia , Asma/terapia , Carboidratos/administração & dosagem , Citocinas/antagonistas & inibidores , Regulação para Baixo/imunologia , Pulmão/imunologia , Eosinofilia Pulmonar/terapia , Células Th2/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Alérgenos/toxicidade , Animais , Artemisia/química , Asma/imunologia , Asma/metabolismo , Carboidratos/uso terapêutico , Citocinas/biossíntese , Citocinas/classificação , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/uso terapêutico , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Injeções Intraperitoneais , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/toxicidade , Eosinofilia Pulmonar/imunologia , Eosinofilia Pulmonar/metabolismo , Células Th2/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética
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