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1.
J Ethnopharmacol ; 237: 47-54, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-30898554

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The quality control of Traditional Chinese medicine (TCM) is a scientific problem and an industrial issue, which hampers the development of evidence based TCM. The concept of quality markers (Q-markers) is proposed and has been applied to the quality evaluation of TCM based on its clinical efficacy. However, more specific methods are needed to put this idea into practice. The standard decoction is a representative of decoction used in clinical practice and it can be used for the discovery of Q-markers related to the clinical efficacy of TCM. AIM OF THE STUDY: In this study, a systemic strategy was established to discover Q-markers related to the clinical efficacy of TCM Ephedrae Herba (EH), dried stem of Ephedra sinica Stapf. The different processed materials of EH have different clinical applications, though originating from the same medicinal herb. MATERIALS AND METHODS: The standard decoction of each of the processed materials was prepared and a 1HNMR metabolomics approach and total polysaccharide analysis were used to identify potential Q-markers related to the different clinical applications of EH. Correlation analysis was made of the measured biological activity and the holistic chemical profile. RESULTS: The results showed that total polysaccharides and alkaloids were Q-markers for EH preparations. CONCLUSION: This study demonstrates that the standard decoction is a reasonable research objective to explore chemical markers that correlate with the clinical efficacy of TCM.


Assuntos
Ephedra , Extratos Vegetais/farmacologia , Caules de Planta , Controle de Qualidade , Células HEK293 , Humanos , Luciferases/fisiologia , Metabolômica , Regiões Promotoras Genéticas , Receptor 2 Toll-Like/fisiologia , Fator de Transcrição AP-1/fisiologia , Resultado do Tratamento
2.
World J Surg Oncol ; 17(1): 25, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30704487

RESUMO

BACKGROUND: The abnormal expression of activator protein-1(AP-1) has recently been investigated in a variety of tumors. While the relationship between AP-1 and thyroid cancer is poorly studied, our study was to evaluate the protein expression and clinical value of AP-1 in papillary thyroid carcinoma (PTC). METHODS: The expression of AP-1 was examined by immunohistochemistry on paraffin-embedded tissues obtained from PTC and correspondent paracancerous tissues of 82 patients. RESULTS: Compared with paracancerous tissues, AP-1 expression was significantly elevated in PTC tissues and the positive rate was 79.3% (65/82). Our study found a linear trend relationship between the expression of AP-1 and tumor size. However, the differences in AP-1 expression among gender, age, lymph node metastasis, number of lesions, location of the lesion, and extrathyroid invasion are not statistically significant. CONCLUSIONS: The expression of AP-1 plays an important role in the proliferation process of PTC.


Assuntos
Câncer Papilífero da Tireoide/química , Neoplasias da Glândula Tireoide/química , Fator de Transcrição AP-1/análise , Adolescente , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Masculino , Metaloproteinase 9 da Matriz/análise , Pessoa de Meia-Idade , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Fator de Transcrição AP-1/fisiologia , Adulto Jovem
3.
Mol Biol Rep ; 46(1): 27-39, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30515697

RESUMO

Although NFE2L2 transcription factor is considered to make the most significant contribution to the NFE2L2/AP-1-pathway-dependent antioxidants regulation in the human cell, AP-1 has the potential to provide significant backup and even play an equal role in the cell. Considering this, the present study is focused on revealing how JUN, an AP-1 component, and NFE2L2 contribute to regulation of four target genes containing AREs with embedded TREs-SQSTM1, FTH1, HMOX1 and CBR3 and to cellular oxidative status in general in basal conditions and under pro-oxidative influence. NFE2L2 and JUN were down-regulated in HeLa cells using siRNA-mediated knockdown approach. These cells were subsequently exposed to 400 µM hydrogen peroxide in the medium or equal volume of sterile water. They revealed some evidence of both backup functioning and competing between the two factors. Importantly, JUN demonstrated a high level of participation (inc. as a negative regulator) in functioning of the classic NFE2L2 targets and in cellular oxidative status establishment in general. One of the key findings was a dramatic increase in JUN expression following NFE2L2 knockdown in basal conditions. The both AP-1 and NFE2L2 sub-pathways equally determine the outcome of the NFE2L2/AP-1 pathway activation induced by various stimuli, and the outcome is stimulus type- and stimulus-intensity-specific and results from either of the two eventually dominating sub-pathways.


Assuntos
Fator 2 Relacionado a NF-E2/fisiologia , Estresse Oxidativo/genética , Proteínas Proto-Oncogênicas c-jun/fisiologia , Antioxidantes/metabolismo , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes/métodos , Células HeLa , Heme Oxigenase-1/genética , Humanos , Peróxido de Hidrogênio/metabolismo , Fator 2 Relacionado a NF-E2/genética , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/genética , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/fisiologia
4.
Biochim Biophys Acta Gene Regul Mech ; 1862(1): 1-11, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30317027

RESUMO

Endothelium-derived colony stimulating factor (CSF1) plays a key role in a range of human pathologies. Angiotensin II (Ang II) has been documented to stimulate CSF1 transcription although the underlying epigenetic mechanism remains unclear. Here we report that induction of CSF1 transcription by Ang II in vascular endothelial cells paralleled alterations of signature histone modifications surrounding the CSF1 promoter. Specifically, ChIP assays indicated that there was a simultaneous up-regulation of both acetylated H3 and trimethylated H3K4, indicative of transcriptional activation, and down-regulation of dimethyl H3K9, implicated in transcriptional repression, surrounding the proximal CSF1 promoter. Further analysis revealed that silencing of brahma related gene 1 (BRG1), a chromatin remodeling protein, abrogated CSF1 induction by Ang II. In the meantime, BRG1 silencing erased H3 acetylation and H3K4 trimethylation and restored H3K9 dimethylation. Mechanistically, BRG1 interacted with and recruited SET1A, a histone H3K4 methyltransferase, and JMJD1A, a histone H3K9 demethylase, to the CSF1 promoter to alter chromatin structure thereby promoting CSF1 trans-activation in response to Ang II stimulation. Knockdown of either SET1A or JMJD1A blocked CSF1 induction by Ang II. Finally, we demonstrate that the crosstalk between BRG1 and histone modifying enzymes was mediated by the transcription factor AP-1. In conclusion, our data unveil a novel epigenetic mechanism whereby a BRG1-centered complex mediates transcriptional activation of CSF1 by Ang II in vascular endothelial cells.


Assuntos
Angiotensina II/fisiologia , Células Endoteliais/metabolismo , Epigênese Genética , Fator Estimulador de Colônias de Macrófagos/genética , DNA Helicases/fisiologia , Código das Histonas/genética , Humanos , Proteínas Nucleares/fisiologia , Receptor Cross-Talk , Fator de Transcrição AP-1/fisiologia , Fatores de Transcrição/fisiologia , Transcrição Genética , Ativação Transcricional
5.
Mol Vis ; 24: 647-666, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30310263

RESUMO

Purpose: Systemic hypertension is a risk factor of neovascular age-related macular degeneration; consumption of dietary salt resulting in extracellular hyperosmolarity is a main cause of hypertension. Extracellular hyperosmolarity was shown to induce expression of angiogenic growth factors, such as vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), in RPE cells. The aim of the present study was to determine whether the hyperosmotic expression of growth factor genes in RPE cells is mediated by activator protein-1 (AP-1), and whether c-Fos and c-Jun genes are regulated by extracellular osmolarity. Methods: Hyperosmotic media were made up with the addition of NaCl or sucrose. Gene expression was quantified with real-time reverse transcription (RT)-PCR, and protein secretion was investigated with enzyme-linked immunosorbent assay (ELISA). Nuclear factor of activated T cell 5 (NFAT5) was depleted with siRNA. DNA binding of AP-1 protein was evaluated with electrophoretic mobility shift assay (EMSA). Results: High NaCl and the addition of sucrose triggered expression of the c-Fos gene, but not of the c-Jun gene. High NaCl also increased the levels of c-Fos and phosphorylated c-Jun proteins and the level of DNA binding of AP-1. Hypoosmolarity decreased the expression of the c-Fos and c-Jun genes. NaCl-induced expression of the c-Fos gene was in part mediated by NFAT5. Autocrine/paracrine activation of fibroblast growth factor and adenosine A1 receptors is involved in mediating NaCl-induced expression of the c-Fos gene. Pharmacological inhibition of the AP-1 activity decreased the NaCl-induced expression of the HIF-1α, NFAT5, VEGF, PlGF, and TGF-ß2 genes, and prevented the NaCl-induced secretion of PlGF but not of VEGF. Conclusions: The data indicate that AP-1 is activated in RPE cells in response to extracellular hyperosmolarity and mediates in part via the NaCl-induced expression of VEGF and PlGF, and secretion of PlGF. It is suggested that high consumption of dietary salt may exacerbate the angiogenic response of RPE cells in part via activation of AP-1.


Assuntos
Regulação da Expressão Gênica/fisiologia , Fator de Crescimento Placentário/genética , Epitélio Pigmentado da Retina/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Fator de Transcrição AP-1/fisiologia , Fator A de Crescimento do Endotélio Vascular/genética , Western Blotting , Células Cultivadas , Ensaio de Desvio de Mobilidade Eletroforética , Ensaio de Imunoadsorção Enzimática , Genes fos/fisiologia , Genes jun/fisiologia , Humanos , Fosforilação , Fator de Crescimento Placentário/metabolismo , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Epitélio Pigmentado da Retina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/antagonistas & inibidores , Transfecção , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Future Oncol ; 14(25): 2599-2613, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30073865

RESUMO

AIM: The airway epithelium of smokers exhibits upregulated SPRR3, an indicator of pathogenic keratinization. The mechanisms underlying this phenomenon require investigation. PATIENTS & METHODS: Human bronchial epithelial (HBE) SPRR3 expression was analyzed by smoking status. Primary HBE cells were exposed to cigarette smoke (CS). SPRR3 expression, SPRR3 promoter activity, AP-1 factor binding and AP-1 factors' effects were analyzed. RESULTS: Current smokers display SPRR3 upregulation relative to never smokers. CS upregulates SPRR3 transcription in an exposure-dependent manner. CS promotes c-Jun and Fra1 binding to the SPRR3-AP-1/TRE site. Wild-type c-Jun and Fra1 upregulate, whereas c-Jun and Fra1, dominant-negative mutants, suppress SPRR3 promoter activity. CONCLUSION: CS induces SPRR3 upregulation in HBE cells by promoting aberrant c-Jun/Fra1 dimerization.


Assuntos
Brônquios/metabolismo , Proteínas Ricas em Prolina do Estrato Córneo/genética , Multimerização Proteica , Proteínas Proto-Oncogênicas c-fos/química , Proteínas Proto-Oncogênicas c-jun/química , Fumar Tabaco/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Quinase 7 Ativada por Mitógeno/fisiologia , Proteína Quinase 8 Ativada por Mitógeno/fisiologia , Regiões Promotoras Genéticas , Fator de Transcrição AP-1/fisiologia , Regulação para Cima
7.
Cell ; 174(3): 659-671.e14, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-30053425

RESUMO

The HIV accessory protein Nef counteracts immune defenses by subverting coated vesicle pathways. The 3.7 Å cryo-EM structure of a closed trimer of the clathrin adaptor AP-1, the small GTPase Arf1, HIV-1 Nef, and the cytosolic tail of the restriction factor tetherin suggested a mechanism for inactivating tetherin by Golgi retention. The 4.3 Å structure of a mutant Nef-induced dimer of AP-1 showed how the closed trimer is regulated by the dileucine loop of Nef. HDX-MS and mutational analysis were used to show how cargo dynamics leads to alternative Arf1 trimerization, directing Nef targets to be either retained at the trans-Golgi or sorted to lysosomes. Phosphorylation of the NL4-3 M-Nef was shown to regulate AP-1 trimerization, explaining how O-Nefs lacking this phosphosite counteract tetherin but most M-Nefs do not. These observations show how the higher-order organization of a vesicular coat can be allosterically modulated to direct cargoes to distinct fates.


Assuntos
Fator de Transcrição AP-1/ultraestrutura , Produtos do Gene nef do Vírus da Imunodeficiência Humana/metabolismo , Produtos do Gene nef do Vírus da Imunodeficiência Humana/ultraestrutura , Fator 1 de Ribosilação do ADP/metabolismo , Fator 1 de Ribosilação do ADP/ultraestrutura , Proteínas Adaptadoras de Transporte Vesicular , Antígeno 2 do Estroma da Médula Óssea/metabolismo , Antígeno 2 do Estroma da Médula Óssea/ultraestrutura , Clatrina , Complexo de Golgi , Células HEK293 , HIV-1 , Humanos , Transporte Proteico/fisiologia , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição AP-1/fisiologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana/fisiologia
8.
Eur Rev Med Pharmacol Sci ; 22(7): 2015-2021, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29687857

RESUMO

OBJECTIVE: In Alzheimer's disease (AD), astrocytes are generally found in the surrounding of senile plaques participating in the production of phagocytosis and the removal of toxic compounds such as Aß. This study aimed at investigating the effect of Aß1-42 on astrocytes. MATERIALS AND METHODS: Cellular viability of primary cultured astrocytes was analyzed using CCK-8 assay. Quantitative Real-time PCR was used to assess the mRNA expression of JNK and AP-1. The proteins of JNK/AP-1 pathway were investigated using Western blot. RESULTS: Our findings showed that Aß1-42 inhibited cell viability and promoted apoptosis in astrocytes in primary culture. Additionally, Aß1-42 increased the mRNA expression level of AP-1, but had no effect on the expression of JNK. Furthermore, Aß1-42 increased the protein expression of p-JNK, p-c-jun and Fra-1 and the ratio of p-c-jun/c-jun and p-JNK/JNK. CONCLUSIONS: We showed that Aß1-42 promoted cell apoptosis in astrocytes in primary culture. Furthermore, Aß1-42 activated JNK/AP-1 pathway through promoting the phosphorylation of JNK, c-jun and Fra-1 expression, then inducing cell apoptosis.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Astrócitos/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Fragmentos de Peptídeos/farmacologia , Fator de Transcrição AP-1/fisiologia , Astrócitos/metabolismo , Células Cultivadas , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
PLoS One ; 12(7): e0179615, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28759609

RESUMO

The AP-1 Adaptor Complex assists clathrin-coated vesicle assembly in the trans-Golgi network (TGN) of eukaryotic cells. However, the role of AP-1 in the protozoan Trypanosoma cruzi-the Chagas disease parasite-has not been addressed. Here, we studied the function and localization of AP-1 in different T. cruzi life cycle forms, by generating a gene knockout of the large AP-1 subunit gamma adaptin (TcAP1-γ), and raising a monoclonal antibody against TcAP1-γ. Co-localization with a Golgi marker and with the clathrin light chain showed that TcAP1-γ is located in the Golgi, and it may interact with clathrin in vivo, at the TGN. Epimastigote (insect form) parasites lacking TcAP1-γ (TcγKO) have reduced proliferation and differentiation into infective metacyclic trypomastigotes (compared with wild-type parasites). TcγKO parasites have also displayed significantly reduced infectivity towards mammalian cells. Importantly, TcAP1-γ knockout impaired maturation and transport to lysosome-related organelles (reservosomes) of a key cargo-the major cysteine protease cruzipain, which is important for parasite nutrition, differentiation and infection. In conclusion, the defective processing and transport of cruzipain upon AP-1 ablation may underlie the phenotype of TcγKO parasites.


Assuntos
Doença de Chagas/parasitologia , Cisteína Endopeptidases/química , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/fisiologia , Trypanosoma cruzi/genética , Animais , Animais Geneticamente Modificados , Anticorpos Monoclonais/química , Vesículas Revestidas por Clatrina , Endocitose , Teste de Complementação Genética , Complexo de Golgi/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Organelas , Plasmídeos/metabolismo , Proteínas de Protozoários , Proteínas Recombinantes/química , Rede trans-Golgi/metabolismo
10.
Mol Nutr Food Res ; 61(9)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28267258

RESUMO

SCOPE: Indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM) from Brassica plants are regarded as promising anticancer phytochemicals. The enzyme telomerase is a very attractive target for cancer therapeutics; in normal cells such as lymphocytes, it plays a decisive role for cell maintenance. The effect of I3C and DIM on telomerase in normal human immune cells (PBMC) was studied compared to leukaemia cells (HL-60). Signalling of telomerase regulation via estrogen receptor (ER) was addressed. METHODS AND RESULTS: Short-term treatment with I3C and DIM inhibited telomerase activity in leukaemia cells (>30 µM I3C; >3 µM DIM). In CD3/CD28 activated PBMC, inhibition was stronger, though (>3 µM I3C; >1 µM DIM). DIM long-term treatment resulted in DNA damage induction and proliferation inhibition in PBMC as determined by the comet assay and CFSE staining, respectively. A relevance of ERα/ß-AP1 signaling for telomerase inhibition on enzyme activity, but not transcription level became evident indicating a nonclassical mode for ER regulation of telomerase by DIM. CONCLUSION: Although desired in cancer cells, this study identified a potential adverse impact of I3C and DIM on telomerase action in normal human immune cells, partly mediated by an ER-dependent mechanism. These new findings should be considered for potential chronic high-dose chemoprevention strategies using these compounds.


Assuntos
Brassica/química , Receptor alfa de Estrogênio/fisiologia , Receptor beta de Estrogênio/fisiologia , Indóis/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Telomerase/antagonistas & inibidores , Fator de Transcrição AP-1/fisiologia , Dano ao DNA , Células Hep G2 , Humanos
11.
Mediators Inflamm ; 2017: 2401027, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29348704

RESUMO

Vagus nerve stimulation through alpha7 nicotine acetylcholine receptors (α7-nAChR) signaling had been demonstrated attenuation of inflammation. This study aimed to determine whether PNU-282987, a selective α7-nAChR agonist, affected activities of matrix metalloproteinase (MMP) and inflammatory cytokines in nicotine-treatment RAW264.7 and MOVAS cells and to assess the underlying molecular mechanisms. RAW264.7 and MOVAS cells were treated with nicotine at different concentrations (0, 1, 10, and 100 ng/ml) for 0-120 min. Nicotine markedly stimulated the phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2) and c-Jun in RAW264.7 cells. Pretreatment with U0126 significantly suppressed phosphorylation of ERK1/2 and further attenuated nicotine-induced activation of c-Jun and upregulation of MMP-2, MMP-9, monocyte chemotactic protein- (MCP-) 1, and regulated upon activation normal T cell expressed and secreted (RANTES). Similarly, nicotine treatment also increased phosphorylation of c-Jun and expressions of MMP-2, MMP-9, MCP-1, and RANTES in MOVAS cells. When cells were pretreated with PNU-282987, nicotine-induced activations of ERK1/2 and c-Jun in RAW264.7 cells and c-Jun in MOVAS cells were effectively inhibited. Furthermore, nicotine-induced secretions of MMP-2, MMP-9, MCP-1, and RANTES were remarkably downregulated. Treatment with α7-nAChR agonist inhibits nicotine-induced upregulation of MMP and inflammatory cytokines through modulating ERK1/2/AP-1 signaling in RAW264.7 cells and AP-1 in MOVAS cells, providing a new therapeutic for abdominal aortic aneurysm.


Assuntos
Quimiocina CCL2/genética , Quimiocina CCL5/genética , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Metaloproteinases da Matriz/genética , Nicotina/farmacologia , Transdução de Sinais/fisiologia , Fator de Transcrição AP-1/fisiologia , Receptor Nicotínico de Acetilcolina alfa7/fisiologia , Animais , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Butadienos/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Nitrilos/farmacologia , Fosforilação , Células RAW 264.7 , Regulação para Cima/fisiologia , Receptor Nicotínico de Acetilcolina alfa7/agonistas
12.
Photochem Photobiol ; 92(6): 816-825, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27859308

RESUMO

Cutaneous exposure to solar ultraviolet (UV) radiation is a major causative factor in skin carcinogenesis, and improved molecular strategies for efficacious chemoprevention of nonmelanoma skin cancer (NMSC) are urgently needed. Toll-like receptor 4 (TLR4) signaling has been shown to drive skin inflammation, photoimmunosuppression, and chemical carcinogenesis. Here we have examined the feasibility of genetic and pharmacological antagonism targeting cutaneous TLR4 for the suppression of UV-induced NF-κB and AP-1 signaling in keratinocytes and mouse skin. Using immunohistochemical and proteomic microarray analysis of human skin, we demonstrate for the first time that a significant increase in expression of TLR4 occurs in keratinocytes during the progression from normal skin to actinic keratosis, also detectible during further progression to squamous cell carcinoma. Next, we demonstrate that siRNA-based genetic TLR4 inhibition blocks UV-induced stress signaling in cultured keratinocytes. Importantly, we observed that resatorvid (TAK-242), a molecularly targeted clinical TLR4 antagonist, blocks UV-induced NF-κB and MAP kinase/AP-1 activity and cytokine expression (Il-6, Il-8, and Il-10) in cultured keratinocytes and in topically treated murine skin. Taken together, our data reveal that pharmacological TLR4 antagonism can suppress UV-induced cutaneous signaling, and future experiments will explore the potential of TLR4-directed strategies for prevention of NMSC.


Assuntos
Queratinócitos/efeitos dos fármacos , NF-kappa B/fisiologia , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Sulfonamidas/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Fator de Transcrição AP-1/fisiologia , Animais , Humanos , Queratinócitos/metabolismo , Camundongos , Protetores contra Radiação/farmacologia , Transdução de Sinais/efeitos da radiação , Raios Ultravioleta
13.
Nucleic Acids Res ; 44(22): 10727-10743, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27694624

RESUMO

A coordinated and faithful DNA damage response is of central importance for maintaining genomic integrity and survival. Here, we show that exposure of human cells to benzo(a)pyrene 9,10-diol-7,8-epoxide (BPDE), the active metabolite of benzo(a)pyrene (B(a)P), which represents a most important carcinogen formed during food preparation at high temperature, smoking and by incomplete combustion processes, causes a prompt and sustained upregulation of the DNA repair genes DDB2, XPC, XPF, XPG and POLH. Induction of these repair factors on RNA and protein level enhanced the removal of BPDE adducts from DNA and protected cells against subsequent BPDE exposure. However, through the induction of POLH the mutation frequency in the surviving cells was enhanced. Activation of these adaptive DNA repair genes was also observed upon B(a)P treatment of MCF7 cells and in buccal cells of human volunteers after cigarette smoking. Our data provide a rational basis for an adaptive response to polycyclic aromatic hydrocarbons, which occurs however at the expense of mutations that may drive cancer formation.


Assuntos
Apoptose , Reparo do DNA , Ativação Transcricional , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/farmacologia , Sobrevivência Celular , Adutos de DNA/genética , Adutos de DNA/metabolismo , Dano ao DNA , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Retroalimentação Fisiológica , Humanos , Células MCF-7 , Mutagênicos/farmacologia , Fator de Transcrição AP-1/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
14.
Am J Chin Med ; 44(6): 1111-1125, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27627914

RESUMO

Xanthium strumarium L. (Asteraceae), a traditional Chinese medicine, is prescribed to treat arthritis, bronchitis, and rhinitis. Although the plant has been used for many years, the mechanism by which it ameliorates various inflammatory diseases is not yet fully understood. To explore the anti-inflammatory mechanism of methanol extracts of X. strumarium (Xs-ME) and its therapeutic potential, we used lipopolysaccharide (LPS)-stimulated murine macrophage-like RAW264.7 cells and human monocyte-like U937 cells as well as a LPS/D-galactosamine (GalN)-induced acute hepatitis mouse model. To find the target inflammatory pathway, we used holistic immunoblotting analysis, reporter gene assays, and mRNA analysis. Xs-ME significantly suppressed the up-regulation of both the activator protein (AP)-1-mediated luciferase activity and the production of LPS-induced proinflammatory cytokines, including interleukin (IL)-1[Formula: see text], IL-6, and tumor necrosis factor (TNF)-[Formula: see text]. Moreover, Xs-ME strongly inhibited the phosphorylation of mitogen-activated protein kinase (MAPK) in LPS-stimulated RAW264.7 and U937 cells. Additionally, these results highlighted the hepatoprotective and curative effects of Xs-ME in a mouse model of LPS/D-GalN-induced acute liver injury, as assessed by elevated serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and histological damage. Therefore, our results strongly suggest that the ethnopharmacological roles of Xs-ME in hepatitis and other inflammatory diseases might result from its inhibitory activities on the inflammatory signaling of MAPK and AP-1.


Assuntos
Anti-Inflamatórios , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/genética , Citocinas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Terapia de Alvo Molecular , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/fisiologia , Xanthium/química , Doença Aguda , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Células HEK293 , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/isolamento & purificação , Células RAW 264.7 , Transdução de Sinais/fisiologia , Células U937
15.
Am J Rhinol Allergy ; 30(4): 128-33, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27456588

RESUMO

BACKGROUND: Wogonin has been shown to have antifibrotic and anti-inflammatory effects in the lower airway. The purpose of this study was to evaluate the effects of wogonin on transforming growth factor (TGF) ß1-induced myofibroblast differentiation, extracellular matrix production, migration, and collagen contraction, and to determine the molecular mechanisms of wogonin in nasal polyp-derived fibroblasts (NPDF). METHODS: NPDFs were isolated from nasal polyps from eight patients. TGF-ß1-induced NPDFs were treated with wogonin. Cytotoxicity was evaluated by using a 3-(4,5- dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay. Fibroblast migration was evaluated with transwell and scratch migration assays. The expression levels of α-smooth muscle actin, fibronectin, phosphorylated-p38, and c-Fos were determined by Western blot and/or reverse transcription-polymerase chain reaction. The total collagen amount was analyzed with the Sircol collagen assay, and contractile activity was measured by a collagen gel contraction assay. RESULTS: Wogonin (0-60 µM) had no significant cytotoxic effects on TGF-ß1-induced NPDFs. Migration of NPDFs was significantly inhibited by wogonin treatment. The expression levels of α-smooth muscle actin and fibronectin were significantly reduced in wogonin-treated NPDFs. Collagen production and contraction were also significantly decreased by wogonin treatment. Wogonin markedly inhibited activation of the p38/activator protein 1 pathway in TGF-ß1-induced NPDFs. CONCLUSION: These results indicated that wogonin may inhibit TGF-ß1-induced myofibroblast differentiation, extracellular matrix production, migration, and collagen contraction through the p38/activator protein-1 pathway in NPDFs.


Assuntos
Matriz Extracelular/metabolismo , Flavanonas/farmacologia , Pólipos Nasais/patologia , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/fisiologia , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Humanos , Miofibroblastos/citologia , Miofibroblastos/efeitos dos fármacos , Transdução de Sinais/fisiologia
16.
Drug Metab Rev ; 48(3): 351-68, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27286171

RESUMO

Polyunsaturated fatty acids (PUFAs) undergo cytochrome P450 (CYP)-dependent oxidation to epoxides that modulate important physiological functions, including vasoactivity, inflammation, nociception, proliferation and viability. One of the most important human CYP epoxygenases is human CYP2J2 that is widely expressed in tissues, especially heart, vascular smooth muscle, salivary glands and placenta. Recent studies have shown that overexpression of CYP2J2 in vivo reverses several pathological processes in animals, including hypertension and other cardiovascular pathologies and insulin resistance. Information on the molecular regulation of CYP2J2 is sparse but supports roles for specificity protein-1 (Sp1) and activator protein-1 (AP-1) in transcription and the micro-RNA Let-7b in post-transcriptional regulation. Exposure to stress stimuli, including pro- and antioxidant factors and pro-inflammatory cytokines regulates CYP2J2, possibly in a cell-specific fashion. CYP2J2 is also subject to genetic variation and the promoter region SNP (CYP2J2-76G > T; *7 allele) reportedly decreases epoxygenase activity in vivo. Several studies have suggested that carriers of the *7 allele may be predisposed to adverse cardiovascular and related health outcomes, although other studies report different findings. Greater understanding of the mechanisms by which CYP2J2 is regulated could provide insights into important pathogenic processes in complex disease states. Such studies may also lead to the development of novel therapeutic strategies that seek to activate CYP2J2 expression in tissues. Additionally, the development of agents that promote fatty acid epoxide production, or stable analogs that retain the activities of the epoxides, offer promising new avenues for utilizing the beneficial actions of these molecules.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Regulação Enzimológica da Expressão Gênica , Animais , Ácidos Graxos Insaturados/metabolismo , Ácidos Graxos Insaturados/fisiologia , Humanos , Hipertensão/fisiopatologia , Resistência à Insulina/fisiologia , MicroRNAs/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Fator de Transcrição Sp1/fisiologia , Fator de Transcrição AP-1/fisiologia
17.
Tumour Biol ; 37(9): 12153-12160, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27220321

RESUMO

Multidrug resistance is one of the major reasons colorectal cancer (CRC) chemotherapy-based treatments fail, and novel biologically based therapies are urgently needed. Src homology 3 (SH3)-domain GRB2-like protein 1 (SH3GL1) is a membrane-bound protein which was found to be involved in tumor formation, progression, and metastasis. In this study, immunohistochemistry staining, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis revealed a high expression of SH3GL1 in human CRC tumor specimens and several CRC cells resistant to chemotherapeutics. Cell Counting Kit-8 (CCK-8) assay showed that transfection of pCDNA3.1(+)-SH3GL1 increased while transfection of SH3GL1 siRNA decreased cell viability in response to 5-fluorouracil (5-FU) treatment (P < 0.05). Further studies indicated that transfection of SH3GL1 siRNA significantly downregulated multidrug resistance protein 1 (MDR1)/P-glycoprotein expression (P < 0.05), decreased MDR1 promoter activity and activator protein-1 (AP-1) binding activity (P < 0.05), and inhibited the activation of epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinases 1/2 (ERK1/2) signaling (P < 0.05) in CRC cells resistant to chemotherapeutics. Transfection of pCDNA3.1(+)-SH3GL1 caused the opposite effect. Additionally, pre-treatment with either EGFR kinase inhibitor PD153035 or ERK1/2 kinase inhibitor PD98059 in HCT116/5-FU cells partly inhibits P-glycoprotein expression and AP-1 binding activity (P < 0.05). In conclusion, we confirmed that inhibition of SH3GL1 reverses multidrug resistance through declining P-glycoprotein expression via the EGFR/ERK/AP-1 pathway.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Receptores ErbB/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Fator de Transcrição AP-1/fisiologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/fisiologia , Idoso , Linhagem Celular Tumoral , Regulação para Baixo , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Transdução de Sinais
18.
Oncol Rep ; 35(2): 1163-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26573109

RESUMO

The Tax protein of human T cell leukemia virus type 1 plays a major role in the pathogenesis of adult T cell leukemia (ATL), an aggressive neoplasia of CD4+ T cells. In the present study, we investigated whether the EGR-1 pathway is involved in the regulation of Tax-induced JNK expression in human Jurkat T cells transfected to express the Tax protein in the presence or absence of PMA or ionomycin. Overexpression of EGR-1 in Jurkat cells transfected to express Tax, promoted the activation of several genes, with the most potent being those that contained AP-1 (Jun/c-Fos), whereas knockdown of endogenous EGR-1 by small interfering RNA (siRNA) somewhat reduced Tax-mediated JNK-1 transcription. Additionally, luciferase-based AP-1 and NF-κB reporter gene assays demonstrated that inhibition of EGR-1 expression by an siRNA did not affect the transcriptional activity of a consensus sequence of either AP-1 or NF-κB. On the other hand, the apoptosis assay, using all-trans retinoic acid (ATRA) as an inducer of apoptosis, confirmed that siRNA against EGR-1 failed to suppress ATRA-induced apoptosis in Jurkat and Jurkat-Tax cells, as noted by the low levels of both DEVDase activity and DNA fragmentation, indicating that the induction of apoptosis by ATRA was Egr-1-independent. Finally, our data showed that activation of Tax by JNK-1 was not dependent on the EGR-1 cascade of events, suggesting that EGR-1 is important but not a determinant for the activity for Tax-induced proliferation of Jurkat cells.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/fisiologia , Produtos do Gene tax/fisiologia , Proteína Quinase 8 Ativada por Mitógeno/fisiologia , Proteínas de Neoplasias/fisiologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Divisão Celular , Sequência Consenso , Proteína 1 de Resposta de Crescimento Precoce/genética , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Produtos do Gene tax/genética , Humanos , Células Jurkat , NF-kappa B/fisiologia , Proteínas de Neoplasias/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Acetato de Tetradecanoilforbol/farmacologia , Fator de Transcrição AP-1/fisiologia , Transfecção , Tretinoína/farmacologia
19.
Cell Mol Life Sci ; 73(3): 459-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26507244

RESUMO

The paracaspase MALT1 has a central role in the activation of lymphocytes and other immune cells including myeloid cells, mast cells and NK cells. MALT1 activity is required not only for the immune response, but also for the development of natural Treg cells that keep the immune response in check. Exaggerated MALT1 activity has been associated with the development of lymphoid malignancies, and recently developed MALT1 inhibitors show promising anti-tumor effects in xenograft models of diffuse large B cell lymphoma. In this review, we provide an overview of the present understanding of MALT1's function, and discuss possibilities for its therapeutic targeting based on recently developed inhibitors and animal models.


Assuntos
Caspases/fisiologia , Proteínas de Neoplasias/fisiologia , Motivos de Aminoácidos , Animais , Linfócitos B/metabolismo , Linfócitos B/fisiologia , Caspases/metabolismo , Humanos , Imunomodulação/genética , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/fisiologia , Linfoma Difuso de Grandes Células B/genética , Modelos Moleculares , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , NF-kappa B/metabolismo , NF-kappa B/fisiologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Estabilidade de RNA , RNA Mensageiro/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição AP-1/fisiologia
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