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1.
Allergy ; 70(12): 1569-79, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26335962

RESUMO

BACKGROUND: House dust mites (HDMs) are the most important source of indoor aeroallergens that contribute to the rising incidence of allergic diseases such as allergic asthma. The major HDM, Der f 2, induces inflammatory cytokine expression. Little is known about the signaling pathway involved. OBJECTIVE: We wanted to define the Der f 2 signaling pathway from its receptor to the transcription factor responsible for IL-13 expression and production. METHODS: Human bronchial epithelial cells were stimulated with Der f 2. The release and gene expression of IL-13 were measured by means of ELISA and RT-PCR, respectively. In the airway inflammation mouse model, airway responses were assessed using ELISA, histology, BAL fluid, and methacholine responsiveness. RESULTS: Here, we show that Der f 2 binds to TLR4 and induces IL-13 expression and production. In the airway inflammation mouse model, Der f 2-induced IL-13 production significantly decreased with treatment of TAK-242, a novel TLR4 inhibitor. Activation of TLR4 by Der f 2 requires the recruitment and activation of Syk, which leads to phosphorylation of PLCγ and membrane translocation of PKCα. p38 MAPK is then activated by PKCα and stimulates PLD1 activity by phosphorylating the Thr147 residue of PLD1. PLD1 activation enhanced binding of ROCK1 to ATF-2 and leads to increased expression of IL-13. CONCLUSION: Our data extend the knowledge for a variety of possible roles of PLD1 in allergic disorders including asthma pathogenesis and suggest possible candidacy of PLD1 as a molecular target for novel therapeutic approaches.


Assuntos
Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/imunologia , Interleucina-13/biossíntese , Fosfolipase D/imunologia , Hipersensibilidade Respiratória/imunologia , Transdução de Sinais/imunologia , Animais , Antígenos de Dermatophagoides/metabolismo , Proteínas de Artrópodes/metabolismo , Asma/imunologia , Asma/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Ativação Enzimática/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoprecipitação , Camundongos , Fosfolipase D/metabolismo , Pyroglyphidae/imunologia , Receptor 4 Toll-Like/imunologia , Receptor 4 Toll-Like/metabolismo
2.
Asian-Australas J Anim Sci ; 27(6): 862-70, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25050025

RESUMO

This study was conducted to investigate the effects of brown seaweed (Undaria pinnatifida) by-product and seaweed fusiforme (Hizikia fusiformis) by-product supplementation on growth performance and blood profiles including serum immunoglobulin (Ig) in broilers. Fermentation of seaweeds was conducted by Bacillus subtilis and Aspergillus oryzae. In a 5-wk feeding trial, 750 one-d-old broiler chicks were divided into 5 groups, and were assigned to the control diet or experimental diets including control+0.5% brown seaweed (BS) by-product, control+0.5% seaweed fusiforme (SF) by-product, control+0.5% fermented brown seaweed (FBS) by-product, and control+0.5% fermented seaweed fusiforme (FSF) by-product. As a consequence, body weight gain (BWG) and gain:feed of seaweed by-product groups were clearly higher, when compared to those of control diet group from d 18 to 35 and the entire experimental period (p<0.05). In mortality rate, seaweed by-product groups were significantly lower when compared to control diet group during entire experimental period (p<0.05). However, Feed Intake of experimental diets group was not different from that of the control group during the entire experimental period. Whereas, Feed Intake of fermented seaweed by-product groups was lower than that of non-fermented seaweed groups (p<0.05). Total organ weights, lipids, and glutamic oxalacetic transaminase (GOT) of all treatment groups were not different from those of control group. However, glutamic pyruvate transaminase (GPT) of all treatment groups was higher than that of control group at d 17 (p<0.05). In case of serum Igs concentration, the concentration of IgA antibody in BS, SF, FSF treatment groups was significantly higher than in control group at d 35 (p<0.01). IgA concentration in FBS supplementation groups was negligibly decreased when compared to the control group. IgM concentration in the serums of all treatment groups was significantly higher than in control group (p<0.05) and in fermented seaweed by-product groups were much higher than in non-fermented seaweed groups (p<0.05). On the other hand, IgG concentrations in all treatment groups were lower than in control group (p<0.05). Taken together, our results suggest that by-product dietary supplementation of BS, SF, FBS, and FSF in poultry may provide positive effects of growth performance and immune response.

3.
Tissue Antigens ; 77(6): 572-83, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21457149

RESUMO

In an attempt to enable comprehensive high-resolution genotyping of the swine leukocyte antigen (SLA) gene, we performed a systemic analysis of nucleotide polymorphisms at introns 1 and 2 and exon 2 from diverse alleles of SLA-DRB1 and DRB1 pseudogenes. We amplified and cloned 16 partial sequences of SLA-DRB1 and DRB2 introns 1 and 2 from different alleles, and analyzed them together with sequences of four reported SLA-DRB pseudogenes, DRB2, 3, 4, and 5. The results showed the presence of extreme nucleotide variations within introns 1 and 2 of SLA-DRB-related genes including substitutions and deletions. On the basis of these results, we developed a comprehensive genotyping method for SLA-DRB1 by genomic polymerase chain reaction (PCR) and subsequent direct sequencing. A total of 415 animals were genotyped and 67 allelic combinations from 18 DRB1 alleles were identified. Among them, two alleles, SLA-DRB1*kn04 and *kn05, were previously unreported. SLA-DRB1 genotyping results from this study combined with those of SLA-DQB1 from our previous study presented 10 SLA class II haplotypes, three of which were previously unreported. Population analysis using seven different pig breeds showed differences in the allele frequency of SLA-DRB1 among breeds. Our results should benefit biological experiments requiring sequence-level genotyping results of SLA-DRB1 and further study of the complete genetic diversity of SLA-DRB1 using field samples.


Assuntos
Antígenos HLA-DR/genética , Antígenos de Histocompatibilidade Classe II/genética , Análise de Sequência de DNA/métodos , Alelos , Animais , Sequência de Bases , Primers do DNA , Éxons , Genótipo , Cadeias HLA-DRB1 , Haplótipos , Antígenos de Histocompatibilidade Classe I , Íntrons , Modelos Genéticos , Dados de Sequência Molecular , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Suínos
4.
J Viral Hepat ; 18(7): e298-306, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21692941

RESUMO

The RNA-dependent RNA polymerase (RdRp) of hepatitis C virus (HCV) is the essential catalytic enzyme for viral genome replication. It initiates minus-strand RNA synthesis from a highly conserved 98-nt sequence, called the X-RNA, at the 3'-end of the plus-strand viral genome. In this study, we evaluated the antiviral effects of peptide nucleic acids (PNAs) targeting the X-RNA. Our in vitro RdRp assay results showed that PNAs targeting the three major stem-loop (SL) domains of X-RNA can inhibit RNA synthesis initiation. Delivery of X-RNA-targeted PNAs by fusing the PNAs to cell-penetrating peptides (CPPs) into HCV-replicating cells effectively suppressed HCV replication. Electrophoretic mobility shift assays revealed that the PNA targeting the SL3 region at the 5'-end of X-RNA dissociated the viral RdRp from the X-RNA. Furthermore, delivery of the SL3-targeted PNA into HCV-infected cells resulted in the suppression of HCV RNA replication without activation of interferon ß expression. Collectively, our results indicate that the HCV X-RNA can be effectively targeted by CPP-fused PNAs to block RNA-protein and/or RNA-RNA interactions essential for viral RNA replication and identify X-RNA SL3 as an RdRp binding site crucial for HCV replication. In addition, the ability to inhibit RNA synthesis initiation by targeting HCV X-RNA using antisense PNAs suggests their promising therapeutic potential against HCV infection.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Ácidos Nucleicos Peptídicos/farmacologia , RNA Antissenso/farmacologia , RNA Viral/genética , Replicação Viral/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaio de Desvio de Mobilidade Eletroforética , Hepacivirus/genética , Hepacivirus/fisiologia , Humanos , Immunoblotting , Sequências Repetidas Invertidas/efeitos dos fármacos , RNA Polimerase Dependente de RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas não Estruturais Virais/genética , Replicação Viral/genética
5.
Eur Rev Med Pharmacol Sci ; 25(20): 6397-6407, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34730221

RESUMO

OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a pandemic and leading cause of death. Beyond the deaths directly caused by the virus and the suicides related to the psychological response to the dramatic changes as socioeconomic related to the pandemic, there might also be suicides related to the inflammatory responses of the infection. Infection induces inflammation as a cytokine storm, and there is an increasing number of studies that report a relationship between infection and suicide. MATERIALS AND METHODS: We searched the World Health Organization status report and the PubMed database for keywords (COVID-19, suicide, infection, inflammation, cytokines), and reviewed five cytokine pathways between suicide and inflammation using two meta-analyses and two observational studies starting from November 31, 2020, focusing on the relationship between suicide and inflammation by infection. First, we discussed existing evidence explaining the relationship between suicidal behaviors and inflammation. Second, we summarized the inflammatory features found in COVID-19 patients. Finally, we highlight the potential for these factors to affect the risk of suicide in COVID-19 patients. RESULTS: Patients infected with COVID-19 have high amounts of IL-1ß, IFN-γ, IP10, and MCP1, which may lead to Th1 cell response activation. Also, Th2 cytokines (e.g., IL-4 and IL-10) were increased in COVID-19 infection. In COVID-19 patients, neurological conditions, like headache, dizziness, ataxia, seizures, and others have been observed. CONCLUSIONS: COVID-19 pandemic can serve as a significant environmental factor contributing directly to increased suicide risk; the role of inflammation by an infection should not be overlooked.


Assuntos
COVID-19/imunologia , Citocinas/imunologia , Suicídio , COVID-19/psicologia , Humanos , Fatores de Risco , Suicídio/psicologia
6.
J Viral Hepat ; 16(10): 697-704, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19243496

RESUMO

Hepatitis C virus (HCV) infection is a serious threat to human health worldwide. In spite of the continued search for specific and effective anti-HCV therapies, the rapid emergence of drug-resistance variants has been hampering the development of anti-HCV drugs designed to target viral enzymes. Targeting host factors has therefore emerged as an alternative strategy offering the potential to circumvent the ever-present complication of drug resistance. We previously identified protein kinase C-related kinase 2 (PRK2) as a cellular kinase that phosphorylates the HCV RNA-dependent RNA polymerase (RdRp). Here, we report the anti-HCV activity of HA1077, also known as fasudil, and Y27632, which blocks HCV RdRp phosphorylation by suppressing PRK2 activation. Treatment of a Huh7 cell line, stably expressing a genotype 1b HCV subgenomic replicon RNA, with 20 microm each of HA1077 and Y27632 reduced the HCV RNA level by 55% and 30%, respectively. A combination of the inhibitors with 100 IU/mL interferon alpha (IFN-alpha) significantly potentiated the anti-HCV drug activities resulting in approximately a 2-log(10) viral RNA reduction. We also found that IFN-alpha does not activate PRK2 as well as its upstream kinase PDK1 in HCV-replicating cells. Furthermore, treatment of HCV-infected cells with 20 microm each of HA1077 and Y27632 reduced the levels of intracellular viral RNA by 70% and 92%, respectively. Taken together, the results identify PRK2 inhibitors as potential antiviral drugs that act by suppressing HCV replication via inhibition of viral RNA polymerase phosphorylation.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Amidas/farmacologia , RNA Polimerases Dirigidas por DNA/metabolismo , Hepacivirus/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Linhagem Celular , Hepatócitos/virologia , Humanos , Interferon-alfa/farmacologia , Fosforilação
7.
Ann Oncol ; 19(4): 675-81, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18037623

RESUMO

BACKGROUND: To investigate the association between tumor markers [cancer antigen 15-3 (CA 15-3) and carcinoembryonic antigen (CEA)] and clinicopathological parameters and patient outcomes in breast cancer. MATERIALS AND METHODS: A total of 740 patients with stages I-III breast cancer had preoperative CA 15-3 and CEA concentrations measured. Univariate and multivariate analyses were used to investigate associations between marker concentration and clinicopathological parameters and patient outcomes. RESULTS: Among 740 patients, elevated preoperative levels of CA 15-3 and CEA were identified in 92 (12.4%) and 79 (10.7%) patients, respectively. Tumor size (>5 cm), node metastases (> or =4), and advanced stage (> or =III) were associated with higher preoperative levels. Elevated CA 15-3 and CEA levels were associated with poor disease-free survival (DFS, P = 0.0014, P = 0.0001, respectively) and overall survival (OS, P = 0.018, P = 0.015) even in stage-matched analysis. Patients with normal levels of both CA 15-3 and CEA showed better DFS and OS than those with elevated group. In multivariate analysis, age (<35 years), tumor size (>2 cm), node metastases, estrogen receptor expression, and elevated CA 15-3 and CEA preoperative values were independent prognostic factors for DFS. CONCLUSION: High preoperative CA 15-3 and CEA levels may reflect tumor burden and are associated with advanced disease and poor outcome. Measuring preoperative levels of CA 15-3 and CEA can be helpful for predicting outcomes.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Antígeno Carcinoembrionário/sangue , Mucina-1/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Prognóstico , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
8.
Cancer Res ; 61(7): 3084-91, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11306491

RESUMO

Fas transduces not only apoptotic signals through various pathways but also angiogenic and proinflammatory responses in vivo. Human glioma cells express Fas although sensitivity to Fas-mediated cell death is variable, suggesting that Fas may have functions other than apoptosis in these cells. In this study, we addressed alternative functions of Fas expressed on human gliomas by Fas ligation in three human glioma cell lines, CRT-MG, U373-MG, and U87-MG, and the in vivo expression of Fas and chemokines in human glioblastoma multiforme (GBM). Herein, we demonstrate that: (a) stimulation with agonistic anti-Fas monoclonal antibody CH-11 and human recombinant soluble Fas ligand induces expression of the CC chemokine MCP-1 and the CXC chemokine interleukin-8 by human glioma cell lines at the mRNA and protein levels in a dose- and time-dependent manner; (b) selective pharmacological inhibitors of MEK1 (U0126 and PD98059) and p38 mitogen-activated protein kinase (MAPK) (SB202190) suppress Fas-mediated chemokine expression in a dose-dependent manner; (c) Fas ligation on human glioma cells leads to activation of both extracellular signal-regulated kinases ERK1/ERK2 and p38 MAPK; and (d) GBM samples express higher levels of Fas compared with normal control brain, which correlates with increased interleukin 8 expression. These findings indicate that Fas ligation on human glioma cells leads to the selective induction of chemokine expression, which involves the ERK1/ERK2 and p38 MAPK signaling pathways. Therefore, the Fas-Fas ligand system in human brain tumors may be involved not only in apoptotic processes but also in the provocation of angiogenic and proinflammatory responses.


Assuntos
Quimiocinas/biossíntese , Glioma/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Receptor fas/fisiologia , Adulto , Apoptose/fisiologia , Glioblastoma/enzimologia , Glioblastoma/imunologia , Glioblastoma/metabolismo , Glioma/enzimologia , Glioma/imunologia , Humanos , Interleucina-8/biossíntese , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Células Tumorais Cultivadas , Receptor fas/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno
9.
Oncogenesis ; 5: e221, 2016 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-27136675

RESUMO

MUDENG (Mu-2-related death-inducing gene, MuD) is revealed to be involved in cell death signaling. Astrocytes, the major glial cell type in the central nervous system, are a source of brain tumors. In this study, we examined MuD expression and function in human astroglioma cells. Stimulation of U251-MG cells with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resulted in a 40% decrease in cell viability and a 33% decrease in MuD protein levels, although not in MuD mRNA levels. To study the functional relevance of MuD expression, stable transfectants expressing high levels of MuD were generated. Stimulation of these transfectants with TRAIL resulted in enhanced cell survival (77% for stable and 46% for control transfectants). Depletion of MuD led to a marked reduction upon TRAIL stimulation in cell viability (22% in MuD-depleted cells and 54% in control cells). In addition, we observed that MuD depletion increased the susceptibility of the cells to TRAIL by enhancing the cleavage of caspase-3/-9 and BH3-interacting domain death agonist (Bid). A unique 25-kDa fragment of B-cell lymphoma 2 (Bcl-2) lacking BH4 was observed 60-180 min post TRAIL treatment in MuD-depleted cells, suggesting that Bcl-2 is converted from its anti-apoptotic form to the truncated pro-apoptotic form. Importantly, the TRAIL-mediated decrease in cell viability in MuD-depleted cells was abrogated upon Bid depletion, indicating that the role of MuD in apoptotic signaling takes place at the Bid and Bcl-2 junction. MuD localizes predominantly in the endoplasmic reticulum and partly in the mitochondria and its amounts are reduced 6 h post TRAIL stimulation, presumably via caspase-3-mediated MuD cleavage. Collectively, these results suggest that MuD, a novel signaling protein, not only possesses an anti-apoptotic function but may also constitute an important target for the design of ideal candidates for combinatorial treatment strategies for glioma cells.

10.
Mol Oral Microbiol ; 31(5): 398-409, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26403493

RESUMO

We investigated the roles of peroxisome proliferator-activated receptor δ (PPARδ) in Porphyromonas gingivalis-derived lipopolysaccharide (Pg-LPS)-induced activation of matrix metalloproteinase 2 (MMP-2). In human gingival fibroblasts (HGFs), activation of PPARδ by GW501516, a specific ligand of PPARδ, inhibited Pg-LPS-induced activation of MMP-2 and generation of reactive oxygen species (ROS), which was associated with reduced expression of NADPH oxidase 4 (Nox4). These effects were significantly smaller in the presence of small interfering RNA targeting PPARδ or the specific PPARδ inhibitor GSK0660, indicating that PPARδ is involved in these events. In addition, modulation of Nox4 expression by small interfering RNA influenced the effect of PPARδ on MMP-2 activity, suggesting a mechanism in which Nox4-derived ROS modulates MMP-2 activity. Furthermore, c-Jun N-terminal kinase and p38, but not extracellular signal-regulated kinase, mediated PPARδ-dependent inhibition of MMP-2 activity in HGFs treated with Pg-LPS. Concomitantly, PPARδ-mediated inhibition of MMP-2 activity was associated with the restoration of types I and III collagen to levels approaching those in HGFs not treated with Pg-LPS. These results indicate that PPARδ-mediated downregulation of Nox4 modulates cellular redox status, which in turn plays a critical role in extracellular matrix homeostasis through ROS-dependent regulation of MMP-2 activity.


Assuntos
Fibroblastos/microbiologia , Lipopolissacarídeos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , NADPH Oxidases/genética , PPAR delta/metabolismo , Porphyromonas gingivalis/metabolismo , Células Cultivadas , Colágeno/genética , Colágeno/metabolismo , Regulação para Baixo , Ativação Enzimática , Fibroblastos/efeitos dos fármacos , Gengiva/citologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lipopolissacarídeos/farmacologia , NADPH Oxidase 4 , PPAR delta/antagonistas & inibidores , PPAR delta/genética , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/patogenicidade , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Sulfonas/farmacologia , Tiazóis/farmacologia , Tiofenos/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Oncogene ; 15(5): 569-77, 1997 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-9247310

RESUMO

Interleukin-6 (IL-6) inhibits the growth of melanocytes and of early stage melanoma cells, but not that of advanced melanoma cells. The in vitro IL-6 response can be restored in the highly metastatic melanoma B16-F10.9 by addition of recombinant soluble IL-6 receptor alpha-chain (sIL-6R). The F10.9 cells then undergo irreversible growth-arrest and show increased adherence with changes from epithelioid to spindleoid morphology. The sIL-6R is required for IL-6 to induce a sustained activation of the various Stat transcription factors which bind to specific IL-6 inducible enhancers. The sIL-6R and IL-6 combination causes an increase in the level of the anti-oncogenic transcription factor IRF-1 protein and DNA-binding, which remain elevated for 24 h. The promoter activity of the anti-oncogenic p21/Waf-1/Cip-1 gene is induced and accumulation of the p21 protein is observed. These results illustrate the potent agonist activity of sIL-6R on molecular pathways which could mediate the growth-arrest and differentiation of the metastatic melanoma cells. Previously observed antimetastatic effects of IL-6 therapy in mice bearing F10.9 tumors may be at least partly due to direct growth inhibition and differentiation elicited by sIL-6R present in biological fluids.


Assuntos
Antígenos CD/metabolismo , Interleucina-6/farmacologia , Melanoma/patologia , Receptores de Interleucina/metabolismo , Animais , Antígenos CD/química , Antígenos CD/genética , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Cricetinae , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/efeitos dos fármacos , Ciclinas/genética , Ciclinas/metabolismo , Proteínas de Ligação a DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Fator Regulador 1 de Interferon , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Camundongos , Fosfoproteínas/efeitos dos fármacos , Fosfoproteínas/metabolismo , Receptores de Interleucina/química , Receptores de Interleucina/genética , Receptores de Interleucina-6 , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT1 , Solubilidade , Transativadores/efeitos dos fármacos , Transativadores/genética , Transativadores/metabolismo , Células Tumorais Cultivadas
12.
J Mol Biol ; 245(5): 608-22, 1995 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-7844830

RESUMO

Recombination between RNAs associated with turnip crinkle virus is thought to occur during plus-strand synthesis at motifs resembling the 5'-ends of genomic, subgenomic and satellite RNAs. Common structural regions encompassing the motifs have been found for major crossover sites on two different minus-strand templates, with junctions preferentially located in a single-stranded region at the 3' base of a hairpin. Base changes, deletions and compensatory alteration constructed in and around the hairpin in the region of the turnip crinkle virus genomic RNA involved in recombination support the importance of the hairpin for normal crossover site selection. This region of the genomic RNA is also important for replication of the viral genomic RNA in plants and protoplasts, suggesting a common link between sequences required for recombination and viral replication.


Assuntos
Conformação de Ácido Nucleico , RNA Viral/genética , Recombinação Genética , Sequência de Bases , Dados de Sequência Molecular , Mutação , Plantas/química , Protoplastos/química , Vírus de RNA/genética , RNA Viral/química , Deleção de Sequência
13.
Mol Plant Microbe Interact ; 8(6): 979-87, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8664506

RESUMO

Carmoviruses are single-stranded, single component RNA viruses that include turnip crinkle virus (TCV) and the recently discovered cardamine chlorotic fleck virus (CCFV). Full-length, biologically active cDNAs were constructed for the TCV-M isolate and the Blue Lake isolate of CCFV. Using chimeric viruses constructed between isolates of TCV that produce mild or severe symptoms when coinoculated with a virulent satellite RNA, a Glu residue at position 1,144 in the polymerase open reading frame was identified as being involved in satellite-mediated symptom expression. To analyze viral determinants involved in resistance, chimeric viruses with precisely exchanged open reading frames were produced between TCV, which does not infect the Arabidopsis thaliana ecotype Dijon (Di-0), and CCFV, which can infect Di-0, TCV with the coat protein of CCFV was able to systemically infect Di-0 although whole plant hybridizations revealed that the hybrid virus spread more slowly than either of the two parental viruses. These results indicate that the two parental viruses. These results indicate that the coat protein is an important viral determinant in the resistance of Di-0 to TCV.


Assuntos
Arabidopsis/virologia , Fases de Leitura Aberta , Vírus de Plantas/genética , Vírus de RNA/genética , RNA , Sequência de Aminoácidos , Capsídeo/genética , Quimera , Clonagem Molecular , Imunidade Inata/genética , Hibridização In Situ , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Doenças das Plantas/virologia , Folhas de Planta/virologia , Vírus de Plantas/patogenicidade , RNA/metabolismo , Vírus de RNA/patogenicidade , RNA Satélite , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Transcrição Gênica , Virulência/genética
14.
Cancer Lett ; 168(1): 57-63, 2001 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-11368878

RESUMO

Deregulation of the cell cycle by overexpression of G1 cyclins, cyclin E and cyclin D1 genes, has been demonstrated to be a prerequisite for the development of human cancer. Recently, cyclin E is proposed to be sufficient for the progression of the G1 cell cycle without cyclin D1. Here we show that the proposed model system was specifically present in human hepatocellular carcinoma (HCC) unlike other human cancers. Of 31 HCC tissues analyzed, 21 (67.7%) exhibited an overexpression of cyclin E protein. In contrast to cyclin E gene expression, cyclin D1 expression was strongly downregulated in 19 (61.2%) HCCs. Interestingly, 65% of HCC tissues with overexpression of the cyclin E gene exhibited downregulation of cyclin D1, suggesting reciprocal deregulation of these cyclins in the G1 progression of the cell cycle. Southern blot analysis proved the amplification of cyclin E gene in HCC with a high level of overexpression. The present findings suggest that the reciprocal deregulation of cyclin E lacking cyclin D1 expression might play a role in G1 progression and the development of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Ciclina D1/biossíntese , Ciclina E/biossíntese , Regulação para Baixo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Southern Blotting , Western Blotting , Ciclo Celular/genética , Humanos
15.
Exp Mol Med ; 32(2): 67-71, 2000 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-10926117

RESUMO

The major house-dust-mite allergen, Der p I, stimulates the phospholipase D (PLD) in peripheral blood mononuclear cells (PBMC) from allergic patients with maximal responses after 30 min exposure. At 30 min, Der p I stimulated PLD activity by 1.4-fold in mild, 1.6-fold in moderate and 2-fold in severe allergic patients over control values (p < 0.05). When the cells were pretreated for 24 h with phorbol myristate acetate to down-regulate protein kinase C (PKC), PLD stimulation by Der p I was largely abolished. These results indicate that in PBMC from allergic patients, Der p I can stimulate PLD activity, and that PKC activation is involved in this stimulation.


Assuntos
Alérgenos/metabolismo , Glicoproteínas/metabolismo , Fosfolipase D/metabolismo , Proteína Quinase C/metabolismo , Adulto , Alérgenos/imunologia , Animais , Antígenos de Dermatophagoides , Regulação para Baixo , Glicoproteínas/imunologia , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Imunoglobulina E/sangue , Técnicas In Vitro , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ácaros/imunologia , Ácaros/metabolismo , Fosfolipase D/imunologia , Testes Cutâneos , Acetato de Tetradecanoilforbol/farmacologia
16.
Mol Cells ; 7(5): 688-93, 1997 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-9387159

RESUMO

The eight mutant integrase (IN) proteins of human immunodeficiency virus type (HIV-1), which have a single point mutation at a highly conserved central region, were prepared, and characterized in terms of their endonucleolytic activities and disintegration activities in vitro. Mutation of two highly conserved amino acids, Asp116 or Glu152, leads to complete loss of both the activities, suggesting that these two amino acids are directly associated with enzymatic functions. In addition, the mutant of the position Ser147 was found to have highly depressed endonucleolytic activity showing that the reaction was very delayed in comparison with that of the wild type. However, significant disintegration was detected in the mutant Ser147, indicating that the enzymatic mechanisms of the endonucleolytic and disintegration activities are not exactly reverse. The integrase protein with a mutation at the conserved amino acid Asn117 or Gly118 had a slight loss of the endonucleolytic activity, while a mutation at the three positions, Tyr143, Ser153, and Lys159, had no detectable effect on their enzymatic activities. These results indicate that only a few of the conserved amino acids are critical for enzymatic activities.


Assuntos
Escherichia coli/genética , Integrase de HIV/química , Integrase de HIV/genética , HIV-1/enzimologia , HIV-1/genética , Mutação Puntual , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Escherichia coli/virologia , Vetores Genéticos , Integrase de HIV/biossíntese , Integrase de HIV/metabolismo , HIV-1/isolamento & purificação , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Estrutura Terciária de Proteína , Integração Viral/genética
17.
Mol Cells ; 12(3): 342-6, 2001 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11804333

RESUMO

Ginsenosides, or ginseng saponins, are biologically active ingredients of Panax ginseng. Accumulating evidence suggests that ginsenosides can alleviate pain from injections of noxious chemicals, such as capsaicin [Nah et al. (2000)]. In this study we examined the effects of ginsenoside Rc on the capsaicin-induced inward current in Xenopus oocytes that expresses the vanilloid receptor 1 (VR1). Ginsenoside Rc enhanced the capsaicin-induced inward current in a concentration-dependent and reversible manner, but ginsenoside Rc itself elicited no membrane currents. The VR1 antagonist capsazepine almost completely blocked the inward current that was elicited by capsaicin plus ginsenoside Rc. We also tested the effect of seven other fractionated ginsenosides (i.e., Rb1, Rb2, Rd, Re, Rf, Rg1, and Rg2) in addition to ginsenoside Rc. We found that six of them significantly enhanced the inward current that is induced by capsaicin with the following order of potency: Rc > Rf > Rg1 approximately Rd > Rb2 > Rb1. These results show the possibility that the in vivo effect of ginsenosides against capsaicin-induced pain is derived from their modulation of the VR1 channel function.


Assuntos
Analgésicos/farmacologia , Oócitos/metabolismo , Receptores de Droga/metabolismo , Saponinas/farmacologia , Xenopus laevis/metabolismo , Animais , Capsaicina/metabolismo , Relação Dose-Resposta a Droga , Feminino , Ginsenosídeos , Canais Iônicos/metabolismo , Dor/tratamento farmacológico , Saponinas/metabolismo
18.
Eur Cytokine Netw ; 6(3): 135-43, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8589270

RESUMO

A panel of monoclonal antibodies against the soluble IL-6 receptor was used to search for linear epitopes by a Pepscan analysis. Two such epitopes were found and the corresponding peptides were synthesized chemically. The peptides were active to inhibit the IL-6 dependent growth of human multiple myeloma cell line and the effect of IL-6 on growth of murine hybridoma cells. The epitope-defined, antagonist peptides reduced the transduction of the IL-6 signal which activates binding of Stat transcription factors to specific enhancers, but did not affect IL-6 binding. These effects were not seen with several other peptides from the IL-6 receptor sequence. A computer three-dimensional model of the IL-6 receptor complex was built and indicates that the antagonist peptides define one of the two possible sites of interaction between the domain-II of the IL-6 receptor molecule and that of the gp130 molecule within the hexameric receptor assembly.


Assuntos
Antígenos CD/metabolismo , Antineoplásicos/farmacologia , Simulação por Computador , Epitopos/farmacologia , Inibidores do Crescimento/farmacologia , Interleucina-6/farmacologia , Glicoproteínas de Membrana/antagonistas & inibidores , Modelos Moleculares , Mieloma Múltiplo/patologia , Fragmentos de Peptídeos/farmacologia , Conformação Proteica , Receptores de Interleucina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Antígenos CD/química , Antígenos CD/imunologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Receptor gp130 de Citocina , Epitopos/química , Inibidores do Crescimento/química , Inibidores do Crescimento/metabolismo , Humanos , Interleucina-6/metabolismo , Substâncias Macromoleculares , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Ligação Proteica/efeitos dos fármacos , Receptores de Interleucina/química , Receptores de Interleucina-6 , Relação Estrutura-Atividade , Células Tumorais Cultivadas/efeitos dos fármacos
19.
Eur Cytokine Netw ; 8(4): 359-65, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9459615

RESUMO

An sIL-6R/IL-6 chimera, directly fusing the natural forms of soluble IL-6 receptor and IL-6, as found in human body fluids, was produced in transfected human cells. The secreted p85 glycoprotein was active at a concentration of 120 pM to produce growth-arrest and spindleoid differentiation of murine melanoma F10.9 cells, which do not respond to IL-6 alone. This fusion protein was as active as the yeast-produced p56 fusion protein containing a shortened sIL-6R, linked through a flexible peptide chain to IL-6 (Hyper IL-6). The concentration of Hyper IL-6 needed to arrest the growth of F10.9 cells was much lower than that needed of a combination of IL-6 and sIL-6R, added separately. Hyper IL-6 was also more active than IL-6 in stimulating growth of murine plasmacytoma T1165 cells, the half maximal stimulation being obtained at 2 pM Hyper IL-6 versus 23 pM for IL-6. In order to evaluate the effect of the fused sIL-6R/IL-6 proteins on human hematopoietic primitive progenitor cells, they were added to suspension cultures of CD34+ cells from human cord blood in addition to both flt3/flk2 ligand (FL) and stem cell factor (SCF). Fused sIL-6R/IL-6 produced a marked stimulation of cell expansion and a marked increase in the number of colony forming units when subsequently plated in semi-solid medium with IL-3, GM-CSF, SCF and erythropoietin. Ex-vivo maintenance and expansion of early progenitor cells in bone marrow transplantation protocols may be a potential application for the sIL-6R/IL-6 chimeric glycoproteins.


Assuntos
Líquidos Corporais/metabolismo , Interleucina-6/química , Receptores de Interleucina-6/química , Proteínas Recombinantes de Fusão/química , Animais , Células CHO , Divisão Celular/fisiologia , Cricetinae , Glicosilação , Humanos , Camundongos , Fenótipo , Plasmocitoma/patologia , Fator de Células-Tronco/farmacologia , Células Tumorais Cultivadas
20.
J Agric Food Chem ; 47(3): 934-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10552394

RESUMO

The growth-inhibiting activity of Coptis japonica (Makino) root-derived materials toward eight human intestinal bacteria was examined using an impregnated paper disk method and compared to that of four commercially available isoquinoline alkaloids [berberine sulfate (BS), berberine iodide (BI), palmatine chloride (PC), and palmatine sulfate(PS)], as well as that of Thea sinensis leaf-derived epigallocatechin gallate (EGCG). The biologically active constituents of the Coptis extract were characterized as the isoquinoline alkaloids berberine chloride (BC), palmatine iodide (PI), and coptisine chloride (CC) by spectral analysis. The growth responses varied with both chemical and bacterial strain used. In a test using 500 microg/disk, BC and PI produced a clear inhibitory effect against Bifidobacterium longum, Bifidobacterium bifidum, Clostridium perfringens, and Clostridium paraputrificum, whereas weak or no inhibition was observed in Bifidobacterium adolescentis, Lactobacillus acidophilus, Lactobacillus casei, and Escherichia coli. At 1000 microg/ disk, CC revealed weak or no growth inhibition toward all test bacteria, whereas EGCG exhibited weak growth inhibition against only C. perfringens and C. paraputrificum. Among various isoquinoline alkaloids, BC exhibited more potent inhibitory activity toward C. perfringens than BI and BS, whereas the inhibitory effect was more pronounced in PI compared to PC and PS. The Coptis root-derived materials did not promote growth of B. longum and C. perfringens.


Assuntos
Alcaloides/farmacologia , Bactérias/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Isoquinolinas/farmacologia , Extratos Vegetais/química , Alcaloides/isolamento & purificação , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Berberina/análogos & derivados , Berberina/farmacologia , Alcaloides de Berberina/farmacologia , Humanos , Isoquinolinas/isolamento & purificação , Raízes de Plantas/química
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