Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21.958
Filtrar
1.
Dokl Biochem Biophys ; 486(1): 163-167, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31367812

RESUMO

The treatment of Arabidopsis thaliana plants with exogenous cytokinin (CK) followed by heat shock (HS) activated the expression of the genes for the plastid transcription machinery but adversely affected the plant viability. Abscisic acid (ABA), conversely, promoted maintaining the resistance to HS and had differentially affected different components of the plastid transcriptional complex. This hormone suppressed the accumulation of transcripts of PEP genes and the genes encoding PAP proteins, which are involved in DNA-RNA metabolism. However, it had no effect or activated the expression of NEP genes and PAP genes, which are involved in the redox regulation, as well as the genes encoding the stress-inducible trans-factor (SIG5) and the plastid transcription Ser/Thr protein kinase (cpCK2). Thus, for the adaptation of plants to elevated temperatures, both increase and decrease in the expression of the genes for the plastid transcriptional machinery with the involvement of various regulatory systems, including phytohormones, are equally significant.


Assuntos
Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Citocininas/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Resposta ao Choque Térmico/genética , Plastídeos/genética , Transcrição Genética/efeitos dos fármacos , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/fisiologia , Resposta ao Choque Térmico/efeitos dos fármacos , Plastídeos/efeitos dos fármacos
2.
Int J Nanomedicine ; 14: 5017-5032, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371944

RESUMO

Background: Epigallocatechin gallate (EGCG), the major anti-inflammatory compound in green tea, has been shown to suppress osteoclast (OC) differentiation. However, the low aqueous solubility of EGCG always leads to poor bioavailability, adverse effects, and several drawbacks for clinical applications. Purpose: In this study, we synthesized EGCG-capped gold nanoparticles (EGCG-GNPs) to solve the drawbacks for clinical uses of EGCG in bone destruction disorders by direct reduction of HAuCl4 in EGCG aqueous solution. Methods and Results: The obtained EGCG-GNPs were negatively charged and spherical. Theoretical calculation results suggested that EGCG was released from GNPs in an acidic environment. Cellular uptake study showed an obviously large amount of intracellular EGCG-GNPs without cytotoxicity. EGCG-GNPs exhibited better effects in reducing intracellular reactive oxygen species levels than free EGCG. A more dramatic anti-osteoclastogenic effect induced by EGCG-GNPs than free EGCG was observed in lipopolysaccharide (LPS)-stimulated bone marrow macrophages, including decreased formation of TRAP-positive multinuclear cells and actin rings. Meanwhile, EGCG-GNPs not only suppressed the mRNA expression of genetic markers of OC differentiation but also inhibited MAPK signaling pathways. Furthermore, we confirmed that EGCG-GNPs greatly reversed bone resorption in the LPS-induced calvarial bone erosion model in vivo, which was more effective than applying free EGCG, specifically in inhibiting the number of OCs, improving bone density, and preventing bone loss. Conclusion: EGCG-GNPs showed better anti-osteoclastogenic effect than free EGCG in vitro and in vivo, indicating their potential in anti-bone resorption treatment strategy.


Assuntos
Catequina/análogos & derivados , Ouro/farmacologia , Nanopartículas Metálicas/química , Osteogênese/efeitos dos fármacos , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Reabsorção Óssea/patologia , Catequina/farmacologia , Morte Celular/efeitos dos fármacos , Teoria da Densidade Funcional , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Ligantes , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Nanopartículas Metálicas/ultraestrutura , Camundongos Endogâmicos BALB C , Modelos Biológicos , Ligante RANK/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Crânio/patologia , Transcrição Genética/efeitos dos fármacos
3.
Chem Biol Interact ; 311: 108786, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31401087

RESUMO

Naturally occurring oleanolic acid (OA) possesses a hepatoprotective activity and ability to inhibit proliferation of human hepatocellular carcinoma cells. Both properties might be related to its anti-inflammatory activity. Its low bioavailability justifies the search for more hydrophilic OA derivatives. The aim of this study was the design and synthesis of four novel OA oxime derivatives conjugated with succinic acid at the C-3 position of oleanane skeleton structure and evaluation of their effect on NF-κB and STATs expression and activation in HepG2 cells. The expression of NF-κB and cyclooxygenase-2 (COX-2), STAT5A/B and STAT3 with its target genes: BAX, BCL-XL and MYC was evaluated after 24 h treatment with tested compounds. The comparison of the levels of cytosolic and nuclear NF-κB subunits p50, p65 and STATs proteins was used as the measure of their activation. The results pointed out the 3-succinyloxyiminoolean-12-en-28-oic acid morpholide (SMAM) as the most potent modulator of NF-κB and STAT3. SMAM significantly reduced the expression and activation of NF-κB as well as its nuclear protein level of p65 subunit. This compound also reduced the expression and activation of STAT3 and STAT5A/B. Combined effect of SMAM on these transcription factors resulted in reduced expression of COX-2, MYC and anti-apoptotic BCL-XL genes. Simultaneously, the increased expression of pro-apoptotic BAX gene was observed. In the cells treated with 3-succinyloxyiminoolean-12-en-28-oic acid (SMAA) the increased expression of BAX was also found. The effects of 3-succinyloxyiminoolean-12-en-28-oic acid benzyl ester (SMAEB) and 3-succinyloxyiminoolean-12-en-28-oic acid methyl ester (SMAEM) were moderate and ambiguous in relation to the tested factors. Moreover, the coordinated action of SMAM on NF-κB and STAT3 confirms their close association in HepG2 cells. We conclude that SMAM efficiently downregulates the key elements of signaling pathways involved in inflammatory driven HCC. Thus, may be considered as a potential chemopreventive or therapeutic agent in this type of cancer.


Assuntos
NF-kappa B/metabolismo , Ácido Oleanólico/análogos & derivados , Oximas/farmacologia , Fatores de Transcrição STAT/metabolismo , Ácido Succínico/química , Carcinoma Hepatocelular , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas , NF-kappa B/genética , Oximas/química , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição STAT/genética , Transcrição Genética/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
4.
Nat Commun ; 10(1): 3004, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31285436

RESUMO

Identity determining transcription factors (TFs), or core regulatory (CR) TFs, are governed by cell-type specific super enhancers (SEs). Drugs to selectively inhibit CR circuitry are of high interest for cancer treatment. In alveolar rhabdomyosarcoma, PAX3-FOXO1 activates SEs to induce the expression of other CR TFs, providing a model system for studying cancer cell addiction to CR transcription. Using chemical genetics, the systematic screening of chemical matter for a biological outcome, here we report on a screen for epigenetic chemical probes able to distinguish between SE-driven transcription and constitutive transcription. We find that chemical probes along the acetylation-axis, and not the methylation-axis, selectively disrupt CR transcription. Additionally, we find that histone deacetylases (HDACs) are essential for CR TF transcription. We further dissect the contribution of HDAC isoforms using selective inhibitors, including the newly developed selective HDAC3 inhibitor LW3. We show HDAC1/2/3 are the co-essential isoforms that when co-inhibited halt CR transcription, making CR TF sites hyper-accessible and disrupting chromatin looping.


Assuntos
Elementos Facilitadores Genéticos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Rabdomiossarcoma/genética , Acetilação/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Ensaios de Triagem em Larga Escala , Inibidores de Histona Desacetilases/química , Histona Desacetilases/química , Humanos , Simulação de Dinâmica Molecular , Sondas Moleculares/química , Sondas Moleculares/farmacologia , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição Box Pareados/genética , Cultura Primária de Células , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Rabdomiossarcoma/patologia , Análise de Sequência de RNA , Transcrição Genética/efeitos dos fármacos
5.
Chem Biol Interact ; 311: 108773, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31351048

RESUMO

Hemangioma (HA) is tumor formed by hyper-proliferation of vascular endothelial cells. However, the potential effects of mono-(2-ethylhexyl) phthalate (MEHP) on the progression of HA are not well illustrated. Our present study revealed that MEHP exposure can significantly increase the in vitro proliferation of hemangioma-derived endothelial cells (HemECs). MEHP treatment can activate yes-associated protein (YAP), a key effector of Hippo pathway, by inhibiting its phosphorylation. The dephosphorylation of YAP induced by MEHP can promote the nuclear accumulation of YAP. Knockdown of YAP or its inhibitor can block MEHP triggered cell proliferation. MEHP can increase the levels of precursor and mature mRNA of YAP in HemECs. As well, MEHP extended the half-life of YAP protein. Mechanistically, MEHP can decrease the phosphorylation of YAP via suppressing the activity of large tumor suppressor kinase 1/2 (LATS1/2) to inhibit it induced degradation of YAP. Further, MEHP increased the expression of interferon regulatory factor 1 (IRF1), which can bind to the promoter of YAP to initiate its transcription. Collectively, we revealed that Hippo-YAP signal is involved in MEHP-induced proliferation of HA cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Dietilexilftalato/análogos & derivados , Hemangioma/patologia , Proteínas Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Apoptose/efeitos dos fármacos , Células Cultivadas , Dietilexilftalato/farmacologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Hemangioma/metabolismo , Humanos , Fatores Reguladores de Interferon/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Estabilidade Proteica/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Transcrição Genética/efeitos dos fármacos
6.
Int J Oncol ; 55(1): 167-178, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31180533

RESUMO

Vascular endothelial growth inhibitor (VEGI; also referred to as TNFSF15 or TL1A) is involved in the modulation of vascular homeostasis. VEGI is known to operate via two receptors: Death receptor­3 (DR3) and decoy receptor­3 (DcR3). DR3, which is thus far the only known functional receptor for VEGI, contains a death domain and induces cell apoptosis. DcR3 is secreted as a soluble protein and antagonizes VEGI/DR3 interaction. Overexpression of DcR3 and downregulation of VEGI have been detected in a number of cancers. The aim of the present study was to investigate the effects of sodium valproate (VPA), a histone deacetylase inhibitor, in combination with hydralazine hydrochloride (Hy), a DNA methylation inhibitor, on the expression of VEGI and its related receptors in human osteosarcoma (OS) cell lines and human microvascular endothelial (HMVE) cells. Combination treatment with Hy and VPA synergistically induced the expression of VEGI and DR3 in both OS and HMVE cells, without inducing DcR3 secretion. In addition, it was observed that the combination of VPA and Hy significantly enhanced the inhibitory effect on vascular tube formation by VEGI/DR3 autocrine and paracrine pathways. Furthermore, the VEGI/VEGF­A immune complex was pulled down by immunoprecipitation. Taken together, these findings suggest that DNA methyltransferase and histone deacetylase inhibitors not only have the potential to induce the re­expression of tumor suppressor genes in cancer cells, but also exert anti­angiogenic effects, via enhancement of the VEGI/DR3 pathway and VEGI/VEGF­A interference.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Hidralazina/farmacologia , Osteossarcoma/tratamento farmacológico , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/biossíntese , Ácido Valproico/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neoplasias Ósseas/irrigação sanguínea , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sinergismo Farmacológico , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Inibidores Enzimáticos/farmacologia , Epigênese Genética , Humanos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Osteossarcoma/irrigação sanguínea , Osteossarcoma/genética , Osteossarcoma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Membro 25 de Receptores de Fatores de Necrose Tumoral/biossíntese , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética , Transcrição Genética/efeitos dos fármacos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
7.
Nat Commun ; 10(1): 2723, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222014

RESUMO

Non-genetic drug resistance is increasingly recognised in various cancers. Molecular insights into this process are lacking and it is unknown whether stable non-genetic resistance can be overcome. Using single cell RNA-sequencing of paired drug naïve and resistant AML patient samples and cellular barcoding in a unique mouse model of non-genetic resistance, here we demonstrate that transcriptional plasticity drives stable epigenetic resistance. With a CRISPR-Cas9 screen we identify regulators of enhancer function as important modulators of the resistant cell state. We show that inhibition of Lsd1 (Kdm1a) is able to overcome stable epigenetic resistance by facilitating the binding of the pioneer factor, Pu.1 and cofactor, Irf8, to nucleate new enhancers that regulate the expression of key survival genes. This enhancer switching results in the re-distribution of transcriptional co-activators, including Brd4, and provides the opportunity to disable their activity and overcome epigenetic resistance. Together these findings highlight key principles to help counteract non-genetic drug resistance.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Transativadores/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Epigênese Genética/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência de RNA , Análise de Célula Única , Transativadores/genética , Transativadores/metabolismo , Transcrição Genética/efeitos dos fármacos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Cell Mol Biol Lett ; 24: 33, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31160892

RESUMO

Background: Induction of lysosomal function and autophagy is regarded as an adaptive mechanism in response to cellular stress. The transcription factor EB (TFEB) has been identified as a master regulator of lysosomal function and autophagy. TFEB is a member of the microphthalmia family of bHLH-LZ transcription factors that includes other members such as micropthalmia-associated transcription factor (MITF), TFE3, and TFEC. TFEB controls lysosome biogenesis and autophagy by upregulation of a family of genes belonging to the Coordinated Lysosomal Expression and Regulation (CLEAR) network. Here, we investigated the expression of TFEB in cells subjected to nutrient deprivation and lysosomal stress. We studied transcriptional induction of TFEB-regulated genes in response to nutrient deprivation and lysosomal stress in retinal pigment epithelial (RPE) cells. Furthermore, we also investigated the induction of autophagy and lysosomal genes upon overexpression of constitutively active form of TFEB. Methods: Expression of TFEB and MITF protein levels were evaluated in cells subjected to prolonged periods of nutrient deprivation. mRNA levels of the CLEAR network genes was measured by quantitative real time PCR (qRT-PCR) analysis in cells deprived of nutrients, treated with ammonium chloride and upon overexpression of constitutively active TFEB. Immunostaining with LC3 antibody was used to measure autophagy flux. Labeling with lysoTracker dye was used to assess lysosomes. Results: Our results show that nutrient deprivation increases protein levels of TFEB and MITF in ARPE-19 cells. Nutrient stress induces the expression of lysosomal (LAMP1, CTSD MCOLN1, SGSH) and autophagy (BECN1) genes. Lysosomal stress also increases the expression of lysosomal (ATP6V0A1 and LAMP1) and autophagy (p62 and BECN1) genes. Our results show that overexpression of constitutively active TFEB also induces the expression of CLEAR network genes. Conclusions: Collectively, these observations suggest that nutrient stress induces the protein expression of both MITF and TFEB in ARPE-19 cells. TFEB-regulated transcriptional program plays an important role in adaptive response of cells during both nutrient and lysosomal stress.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Células Epiteliais/metabolismo , Lisossomos/metabolismo , Epitélio Pigmentado da Retina/patologia , Estresse Fisiológico , Adulto , Cloreto de Amônio/farmacologia , Animais , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Lisossomos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Estresse Fisiológico/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos
9.
Chem Pharm Bull (Tokyo) ; 67(6): 505-518, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31155555

RESUMO

Nucleic acid therapeutics such as antisense and small interfering RNA (siRNA) have attracted increasing attention as innovative medicines that interfere with and/or modify gene expression systems. We have developed new functional oligonucleotides that can target DNA and RNA with high efficiency and selectivity. This review summarizes our achievements, including (1) the formation of non-natural triplex DNA for sequence-specific inhibition of transcription; (2) artificial receptor molecules for 8-oxidized-guanosine nucleosides; and (3) reactive oligonucleotides with a cross-linking agent or a functionality-transfer nucleoside for RNA pinpoint modification.


Assuntos
DNA/química , RNA/química , Reagentes para Ligações Cruzadas/química , DNA/metabolismo , DNA/farmacologia , Humanos , Nucleosídeos/análogos & derivados , Nucleosídeos/farmacologia , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo , Polietilenoglicóis/química , RNA/metabolismo , Telomerase/genética , Telomerase/metabolismo , Transcrição Genética/efeitos dos fármacos
10.
Sci Total Environ ; 677: 590-598, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31071664

RESUMO

Metals and heavy metals are natural contaminants with an increasing presence in aquatic ecosystems as a result of human activities. Although they are mixed in the water, research is usually focused on analyzing them in isolation, so there is a lack of knowledge about their combined effects. The aim of this work was to assess the damage produced by mixtures of cadmium and copper, two frequent metals used in industry, in the harlequin midge Chironomus riparius (Diptera). The effects of acute doses of cadmium and copper were evaluated in fourth instar larvae by analyzing the mRNA levels of six genes related to apoptosis (DRONC, IAP1), immune system (PO1, Defensin), stress (Gp93), and copper homeostasis (Ctr1). DRONC, Ctr1, and IAP1 transcripts are described here for first time in this species. Individual fourth instar larvae were submitted to 10 µM, 1 µM and 0.1 µM of CdCl2 or CuCl2, and mixture. The employed individuals came from different egg masses. Real-time PCR analysis showed a complex pattern of alterations in transcriptional activity for two genes, DRONC and Gp93, while the rest of them did not show any statistically significant differences. The effector caspase DRONC showed upregulation with the highest concentration tested of the mixture. In case of gp93, chaperone involved in regulation of immune response, differences in expression levels were found with 1 and 10 µM Cu and 0.1 and 10 µM of mixtures, compared to control samples. These results suggest that mixtures affect the transcriptional activity differently and produce changes in apoptosis and stress processes, although it is also possible that Gp93 alteration could be related to the immune system since it is homologous to human protein Gp96, which has been related with Toll-like receptors. In conclusion, cadmium and copper mixtures can affect the population by affecting the ability of larvae to respond to the infection and the apoptosis, an important process in the metamorphosis of insects.


Assuntos
Apoptose/efeitos dos fármacos , Cloreto de Cádmio/efeitos adversos , Chironomidae/efeitos dos fármacos , Cobre/efeitos adversos , Proteínas de Insetos/genética , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/efeitos adversos , Animais , Apoptose/genética , Chironomidae/genética , Chironomidae/crescimento & desenvolvimento , Chironomidae/fisiologia , Relação Dose-Resposta a Droga , Proteínas de Insetos/metabolismo , Larva/efeitos dos fármacos , Larva/fisiologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
11.
Lipids Health Dis ; 18(1): 109, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077199

RESUMO

BACKGROUND: Atrial lipid metabolic remodeling is critical for the process of atrial fibrillation (AF). Abnormal Fatty acid (FA) metabolism in cardiomyocytes is involved in the pathogenesis of AF. MET (Metformin), an AMPK (AMP-activated protein kinase) activator, has been found to be associated with a decreased risk of AF in patients with type 2 diabetes. However, the specific mechanism remains unknown. METHODS: Fifteen mongrel dogs were divided into three groups: SR, ARP (pacing with 800 beats/min for 6 h), ARP plus MET (treated with MET (100 mg/kg/day) for two weeks before pacing). We assessed metabolic factors, speed limiting enzymes circulating biochemical metabolites (substrates and products), atrial electrophysiology and accumulation of lipid droplets. RESULTS: The expression of AMPK increased in the ARP group and significantly increased in the MET+ARP group comparing to the SR group. In the ARP group, the expressions of PPARα、PGC-1α and VLCAD were down-regulated, while the concentration of free fatty acid and triglyceride and the lipid deposition in LAA (left atrial appendage) increased. Moreover, AERP and AERPd have also been found abnormally in this process. Pretreatment with MET before receiving ARP reversed the alterations aforementioned. CONCLUSIONS: The FA metabolism in LAA is altered in the ARP group, mainly characterized by the abnormal expression of the rate-limiting enzyme. Metformin reduces lipid accumulation and promotes ß-oxidation of FA in AF models partially through AMPK/PPAR-α/VLCAD pathway. Our study indicates that MET may inhibit the FA lipid metabolic remodeling in AF.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Acil-CoA Desidrogenase de Cadeia Longa/metabolismo , Fibrilação Atrial/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metformina/farmacologia , PPAR alfa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Fibrilação Atrial/fisiopatologia , Estimulação Cardíaca Artificial , Modelos Animais de Doenças , Cães , Ácidos Graxos/metabolismo , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/patologia , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Genética/efeitos dos fármacos
12.
World J Gastroenterol ; 25(15): 1797-1816, 2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31057295

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC. Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network. Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein (YAP) and WW-domain-containing transcriptional co-activator with PDZ-binding motif (TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pancreáticas/genética , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Reposicionamento de Medicamentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Metformina/farmacologia , Metformina/uso terapêutico , Terapia de Alvo Molecular/métodos , Mutação , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Fosfoproteínas/antagonistas & inibidores , Prognóstico , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/genética
13.
Aquat Toxicol ; 212: 138-145, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31125791

RESUMO

Multiple antibiotics are simultaneously detected in aquatic environment, so it is extremely important to study the combined effects of their mixtures. In this study, we investigated the toxic effects of erythromycin (ERY) and enrofloxacin (ENR), added individually or in combination, on Chlorella vulgaris and explored the toxic mechanisms. Results showed that the 96 h-EC50 values of ERY, ENR and ERY-ENR mixture to C. vulgaris were 85.7, 124.5 and 39.9 µg L-1 respectively, and combined toxicity assessment found that joint effect of the two antibiotics was synergism, which was proven by the chlorophyll content in algae. Antioxidant defense system and photosynthesis were involved in toxic mechanisms and the results revealed that both the activities of antioxidant enzymes, and the malondialdehyde (MDA) and glutathione (GSH) contents increased in antibiotic treatments. In addition, the increase was more significant in joint exposure treatment, which implied that the antioxidant defense system was synergistically affected. RT-PCR showed that ERY and ENR upregulated the transcript abundance of psaB, psbC and chlB at low concentrations and the transcription abundance was synergistically increased in combined treatment. Therefore, the risk of the toxicity of antibiotics to aquatic organisms in real environment both at organismal and molecular level increases as a result of their combined presence.


Assuntos
Antioxidantes , Chlorella vulgaris/efeitos dos fármacos , Enrofloxacina/toxicidade , Eritromicina/toxicidade , Transcrição Genética/efeitos dos fármacos , Antibacterianos/farmacologia , Chlorella vulgaris/enzimologia , Chlorella vulgaris/genética , Clorofila/metabolismo , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Glutationa/metabolismo , Malondialdeído , Fotossíntese/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
14.
Chem Biol Interact ; 308: 185-193, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31132328

RESUMO

Cytochrome P450 3A (CYP3A) activity is inhibited, and its expression is suppressed during many diseases, including nonalcoholic fatty liver disease (NAFLD). However, the mechanism is controversial. Here, we report that PXR may not take part in the downregulation of CYP3A during NAFLD. Hepatic CYP3A11 (major subtype of mouse CYP3A) mRNA and protein expression was significantly decreased in both mice fed a high-fat diet (HFD) for 8 weeks and palmitate (PA)-treated mouse primary hepatocytes. Similarly, in HepG2 cells, PA treatment significantly suppressed the CYP3A4 (major subtype of human CYP3A) mRNA level and promoter transcription activity. However, Western blotting analysis found an induction of PXR nuclear translocation during NAFLD in both in vivo and in vitro models. Moreover, immunofluorescence determination also found nuclear translocation effect of PXR by PA stimulation in HepG2 cells. In addition, the siRNA knockdown of PXR did not affect the suppressive effects of PA on the CYP3A4 promoter transcription activity and mRNA levels in HepG2 cells. Similarly, PXR knockdown also did not affect the suppressive effects of PA on CYP3A11 mRNA and protein expression levels in mouse primary hepatoctyes. Taken together, the results showed that the suppressive effect of CYP3A transcription was independent of PXR regulation.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Dieta Hiperlipídica , Hepatopatia Gordurosa não Alcoólica/patologia , Receptor de Pregnano X/metabolismo , Animais , Citocromo P-450 CYP3A/genética , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/veterinária , Palmitatos/farmacologia , Receptor de Pregnano X/antagonistas & inibidores , Receptor de Pregnano X/genética , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Transcrição Genética/efeitos dos fármacos
15.
Food Chem Toxicol ; 130: 122-129, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31100301

RESUMO

Simultaneous mycotoxins toxicity is complex and non-predictable based on their individual toxicities. Beauvericin and Enniatins are emerging mycotoxins highly co-occurrent in food and feed, and their cytotoxicity has been reported in several human cell lines. RNA-seq studies of individual exposure in Jurkat cells demonstrated human genome perturbation mainly affecting mitochondrial pathways, however, both mycotoxins showed differences between their toxic responses. This study investigates the transcriptional effects of combined exposure to Beauvericin and Enniatin B (1:1) (0.1, 0.5, 1.5 µM; 24 h) in Jurkat cells by qPCR on 30 selected target genes (10 mitochondrial, 20 nuclear). Gene expression after combined and individual exposures were compared and functional data analysis (ToxPi) on the most relevant biological processes (cycle and apoptosis regulation; cholesterol metabolism and transport; cellular signaling transduction; cellular stress responses; immune regulation; protein metabolism; retinoic acid metabolism; transcription regulation) was applied to RNA-seq data from individual exposure (1.5, 3, 5 µM; 24 h; Jurkat cells). Transcriptional changes, especially at mitochondrial level, were observed after Beauvericin-Enniatin B co-exposure including down-regulation of antioxidant activity related genes. Different expression patterns between combined and individual exposures were identified. ToxPi analysis confirmed different dose-dependent relationship profiles between these two mycotoxins after individual exposure.


Assuntos
Depsipeptídeos/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Depsipeptídeos/administração & dosagem , Quimioterapia Combinada , Humanos , Células Jurkat , Transcriptoma/efeitos dos fármacos
16.
Chem Commun (Camb) ; 55(42): 5886-5889, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31041938

RESUMO

By coupling in situ [2+3] Huisgen cycloaddition with an in vitro transcription/translation luminescence assay in a crude ribosomal extract, a robust and accurate high-throughput platform was successfully developed and applied for efficient identification of novel structural types of ribosomal inhibitors with antimicrobial activity against drug-resistant bacteria.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Descoberta de Drogas , Ribossomos/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Química Click , Reação de Cicloadição , Farmacorresistência Bacteriana , Ensaios de Triagem em Larga Escala , Concentração Inibidora 50 , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Estudo de Prova de Conceito , Biossíntese de Proteínas/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos
17.
Aquat Toxicol ; 212: 70-76, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077968

RESUMO

Medroxyprogesterone acetate (MPA) is a widely used synthetic progestin and it has been frequently detected in aquatic environments. However, its effects on aquatic organisms remain largely unknown. Here we investigated the chronic effects of MPA on sex differentiation and gonad development in zebrafish. Zebrafish larvae at 20 days post fertilization (dpf) were exposed to 4.32, 42.0, and 424 ng L-1 of MPA until they reached 140 dpf. The results showed that chronic exposure to 42.0 ng L-1 of MPA caused 60% proportion of males as well as significant up-regulation of dmrt1 (˜1.79 fold) and hsd17b3 (˜1.92 fold). Histological analysis showed MPA significantly increased the frequency of immature spermatocytes accompanied with the increased transcription of dmrt1 (˜2.06 fold) and ar (˜1.73 fold) in the testes. Meanwhile, MPA exposure significantly increased the transcription of lhb at all exposure concentrations in the males. In contrast, it significantly suppressed the transcription of lhb (˜-8.06-fold) and fshb (˜-6.35-fold) at 42.0 ng L-1 in the females. Collectively our results demonstrated that MPA had androgenic activity, and could affect sex differentiation and spermatogenesis in zebrafish at environmentally relevant concentrations. The findings from this study suggest that MPA in the aquatic environment may pose potential androgenic risks to fish populations.


Assuntos
Acetato de Medroxiprogesterona/farmacologia , Diferenciação Sexual/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Peixe-Zebra/fisiologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Hormônios/sangue , Masculino , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Razão de Masculinidade , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/sangue , Peixe-Zebra/crescimento & desenvolvimento
18.
Cancer Sci ; 110(8): 2676-2683, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31069877

RESUMO

Well-differentiated liposarcoma (WDLPS) and dedifferentiated liposarcoma (DDLPS) are the most common types of liposarcoma. Although WDLPS and DDLPS patients receive intensive treatment including radical surgery and systemic therapy, their overall 5-year survival rates are 90% and 30%, respectively, indicating that DDLPS is clinically more aggressive. We examined whether adipogenic stimulation induces adipogenesis in human WDLPS/DDLPS cells by using dexamethasone, indomethacin, insulin, and 3-isobutyl-1-methylxanthine (IBMX), all putative medications or drugs. Functional in vitro experiments showed that treatment with these four compounds induced adipogenic potency by transcriptional and translational upregulation of genes related to the maintenance of stemness and adipogenic differentiation. Using in vivo xenograft models, we found that the induction of stemness and adipogenesis inhibited the tumorigenic potency of DDLPS. This study suggests a potential application of drug repositioning in which adipogenesis-inducing compounds could be used to treat DDLPS patients in a clinical setting.


Assuntos
Adipogenia/genética , Desdiferenciação Celular/genética , Proliferação de Células/genética , Lipossarcoma/genética , 1-Metil-3-Isobutilxantina/farmacologia , Adipogenia/efeitos dos fármacos , Desdiferenciação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Dexametasona/farmacologia , Humanos , Indometacina/farmacologia , Insulina/farmacologia , Lipossarcoma/tratamento farmacológico , Lipossarcoma/patologia , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/genética , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
19.
Int J Mol Sci ; 20(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934780

RESUMO

The effects of thyroid hormone disrupting chemicals (THDCs) on eye development of zebrafish were investigated. We expected THDC exposure to cause transcriptional changes of vision-related genes, which find their phenotypic anchoring in eye malformations and dysfunction, as observed in our previous studies. Zebrafish were exposed from 0 to 5 days post fertilization (dpf) to either propylthiouracil (PTU), a thyroid hormone synthesis inhibitor, or tetrabromobisphenol-A (TBBPA), which interacts with thyroid hormone receptors. Full genome microarray analyses of RNA isolated from eye tissue revealed that the number of affected transcripts was substantially higher in PTU- than in TBBPA-treated larvae. However, multiple components of phototransduction (e.g., phosphodiesterase, opsins) were responsive to both THDC exposures. Yet, the response pattern for the gene ontology (GO)-class "sensory perception" differed between treatments, with over 90% down-regulation in PTU-exposed fish, compared to over 80% up-regulation in TBBPA-exposed fish. Additionally, the reversibility of effects after recovery in clean water for three days was investigated. Transcriptional patterns in the eyes were still altered and partly overlapped between 5 and 8 dpf, showing that no full recovery occurred within the time period investigated. However, pathways involved in repair mechanisms were significantly upregulated, which indicates activation of regeneration processes.


Assuntos
Disruptores Endócrinos/toxicidade , Olho/embriologia , Hormônios Tireóideos/toxicidade , Peixe-Zebra/metabolismo , Animais , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Olho/efeitos dos fármacos , Perfilação da Expressão Gênica , Bifenil Polibromatos/toxicidade , Propiltiouracila/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Genética/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
20.
Ecotoxicol Environ Saf ; 179: 310-317, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31030948

RESUMO

Bisphenol A (BPA) is a representative endocrine disrupting chemical (EDC) that has estrogenic effects in aquatic animals. In recent years, due to the continuing usage of BPA, its analogues have been developed as alternative substances to replace its use. The molting process is a pivotal point in the development and reproduction of crustaceans. However, studies of the effects of EDCs on molting in crustaceans at the molecular level are scarce. In the present study, we examined the acute toxicity of BPA and its analogues bisphenol F (BPF) and S (BPS) to the brackish water flea Diaphanosoma celebensis. We further identified four ecdysteroid pathway - related genes (cyp314a1, EcRA, EcRB, and USP) in D. celebensis, and investigated the transcriptional modulation of these genes during molting and after exposure to BPA and its analogues for 48 h. Sequencing and phylogenetic analyses revealed that these four genes are highly conserved among arthropods and may be involved in development and reproduction in the adult stage. The mRNA expression patterns of cyp314a1, EcRA and USP were matched with the molting cycle, suggesting that these genes play a role in the molting process in the adult stage in cladocerans. Following relative real-time polymerase chain reaction (RT-PCR) analyses, BPA and its analogues were found to modulate the expression of each of these four genes differently, indicating that these compounds can disrupt the normal endocrine system function of D. celebensis. This study improves our understanding of the molecular mode of action of BPA and its analogues in D. celebensis.


Assuntos
Compostos Benzidrílicos/toxicidade , Cladóceros/efeitos dos fármacos , Ecdisona/genética , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Águas Salinas/química , Poluentes Químicos da Água/toxicidade , Animais , Compostos Benzidrílicos/química , Cladóceros/genética , Cladóceros/metabolismo , Ecdisona/metabolismo , Fenóis/química , Filogenia , Testes de Toxicidade Aguda , Transcrição Genética/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA