RESUMO
Fatty acid and fat synthesis in the liver is a highly regulated metabolic pathway that is important for very low-density lipoprotein (VLDL) production and thus energy distribution to other tissues. Having common features at their promoter regions, lipogenic genes are coordinately regulated at the transcriptional level. Transcription factors, such as upstream stimulatory factors (USFs), sterol regulatory element-binding protein 1C (SREBP1C), liver X receptors (LXRs) and carbohydrate-responsive element-binding protein (ChREBP) have crucial roles in this process. Recently, insights have been gained into the signalling pathways that regulate these transcription factors. After feeding, high blood glucose and insulin levels activate lipogenic genes through several pathways, including the DNA-dependent protein kinase (DNA-PK), atypical protein kinase C (aPKC) and AKT-mTOR pathways. These pathways control the post-translational modifications of transcription factors and co-regulators, such as phosphorylation, acetylation or ubiquitylation, that affect their function, stability and/or localization. Dysregulation of lipogenesis can contribute to hepatosteatosis, which is associated with obesity and insulin resistance.
Assuntos
Ácidos Graxos/biossíntese , Lipogênese/genética , Lipoproteínas VLDL/biossíntese , Fígado/metabolismo , Transcrição Gênica/genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Proteína Quinase Ativada por DNA/metabolismo , Regulação da Expressão Gênica , Lipogênese/fisiologia , Receptores X do Fígado , Camundongos , Proteínas Nucleares/metabolismo , Receptores Nucleares Órfãos/metabolismo , Proteína Quinase C/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/metabolismo , Fatores Estimuladores Upstream/metabolismoRESUMO
Recent tragedies around the world have shown how accidents in the cable-stayed bridges can wreak havoc on the society. To ensure the safety of the cable-stayed bridges, several studies have estimated the cable tension force using the vibration of cables. Most of these methods for estimating the tension of a cable start with measuring the displacement of the cable. Recent development of commercial cameras provide opportunity for more convenient and efficient method for measuring the displacement of cable. However, traditional vision-based displacement measurement methods require the assumption that the movement of the cable should be measured in parallel to the camera plane. This assumption limits the installation location of the camera when measuring the displacement of a cable. Therefore, this study introduces a new vision-based cable displacement measurement system that can measure the displacement of a cable in various locations even when the camera is installed in the side of the cable. The proposed method consists of three phases: (1) camera projection matrix estimation, (2) cable tracking in the image coordinate, and (3) cable displacement estimation in the world coordinate. To validate the performance of the proposed method, a simulation-based validation test, a lab-scale validation test, and an on-site validation test were conducted. The simulation-based validation test verified the performance of the proposed method in an ideal condition, and the lab-scale validation test showed the performance of the method in physical environment. Finally, the on-site validation test showed that the proposed method can measure the cable displacement with a side view camera.
Assuntos
Movimento , Vibração , Simulação por ComputadorRESUMO
Roles of dietary phytochemicals in cancer chemoprevention via induction of nuclear factor-erythroid-2-related factor 2 (Nrf2)-mediated antioxidant enzymes have been well established in a number of studies. In this study, FACS analysis was used to reveal that the intracellular reactive oxygen species level decreased at 0-25 µM of genipin treatment. Furthermore, immunofluorescence analysis and Western blotting were used to demonstrate that genipin treatment resulted in the upregulation and nuclear translocation of Nrf2, as well as upregulation of gastrointestinal glutathione peroxidase. Finally, we found that C-Jun-NH2-kinase (JNK) was also dose-dependently activated, where depleting JNK by using a biochemical inhibitor indicated that JNK was upstream of Nrf2. Interestingly, the antioxidant effects were limited to the treatment in the lower dosage of genipin, where higher dosage of genipin treatment resulted in the increased reactive oxygen species level and cytotoxicity. Thus, this study demonstrates for the first time that lower dosage of genipin results in the induction of JNK/Nrf2/ARE signaling pathway and protection from cell death.
Assuntos
Adenocarcinoma/metabolismo , Anticarcinógenos/farmacologia , Iridoides/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/enzimologia , Linhagem Celular Tumoral , Humanos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Elementos de Resposta , Neoplasias Gástricas/enzimologiaRESUMO
Natural compounds are becoming important candidates in cancer therapy due to their cytotoxic effects on cancer cells by inducing various types of programmed cell deaths. In this study, we investigated whether genipin induces programmed cell deaths and mediates in Egr1/p21 signaling pathways in gastric cancer cells. Effects of genipin in AGS cancer cell lines were observed via evaluation of cell viability, ROS generation, cell cycle arrest, and protein and RNA levels of p21, Egr1, as well as apoptotic marker genes. The cell viability of AGS cells reduced by genipin treatment via induction of the caspase 3-dependent apoptosis. Cell cycle arrest was observed at the G2/M phase along with induction of p21 and p21-dependent cyclins. As an upstream mediator of p21, the transcription factor early growth response-1 (Egr1) upregulated p21 through nuclear translocation and binding to the p21 promoter site. Silencing Egr1 expression inhibited the expression of p21 and downstream molecules involved in apoptosis. We demonstrated that genipin treatment in AGS human gastric cancer cell line induces apoptosis via p53-independent Egr1/p21 signaling pathway in a dose-dependent manner.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Iridoides/farmacologia , Proteínas Repressoras/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Iridoides/química , Estrutura Molecular , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Relação Estrutura-AtividadeRESUMO
To investigate the underlying mechanism of targets of cyanidin, a flavonoid, which exhibits potent anti-atherogenic activities in vitro and in vivo, a natural chemical library that identified potent agonistic activity between cyanidin and peroxisome proliferator-activated receptors (PPAR) was performed. Cyanidin induced transactivation activity in all three PPAR subtypes in a reporter gene assay and time-resolved fluorescence energy transfer analyses. Cyanidin also bound directly to all three subtypes, as assessed by surface plasmon resonance experiments, and showed the greatest affinity to PPARα. These effects were confirmed by measuring the expression of unique genes of each PPAR subtype. Cyanidin significantly reduced cellular lipid concentrations in lipid-loaded steatotic hepatocytes. In addition, transcriptome profiling in lipid-loaded primary hepatocytes revealed that the net effects of stimulation with cyanidin on lipid metabolic pathways were similar to those elicited by hypolipidemic drugs. Cyanidin likely acts as a physiological PPARα agonist and potentially for PPARß/δ and γ, and reduces hepatic lipid concentrations by rewiring the expression of genes involved in lipid metabolic pathways.
Assuntos
Antocianinas/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , PPAR alfa/agonistas , Animais , Células CHO , Células Cultivadas , Cricetinae , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , PPAR gama/agonistas , PPAR beta/agonistasRESUMO
INTRODUCTION: Firefighters, compared to other occupational groups, are exposed more frequently in their working environment not only to physical issues, such as musculoskeletal disease, respiratory disease, and burns but also to mental health issues, such as PTSD and depression. Specifically, Korean firefighters experience significantly higher rates of work-related injuries compared to those in other countries. Recent statistics from the Korea National Fire Agency indicate a steady increase in the number of firefighting work-related injuries. However, there is a shortage of measures in place to address these issues. This study aims to investigate the health needs, overall healthcare usage, and unmet needs of firefighters in Korea. We also aim to investigate, through in-depth interviews, perceptions and hindering factors for integrative medicine approaches to fulfilling unmet needs. METHOD: This study was conducted in accordance with the consolidated criteria for reporting qualitative research. Convenience and snowball sampling methods will be used to recruit firefighters to participate in the study, and interviews will be conducted using a semi-structured interview guide. The data will be analyzed in four stages using the qualitative analysis method of Krippendorff. DISCUSSION: In this study, we examine the state of health issues and healthcare usage among Korean firefighters and investigate their perceptions of and needs for integrative medicine. In this way, we aim to explore how integrative medicine and Korean medicine approaches could improve and assist healthcare services for firefighters. Furthermore, our findings will provide policymakers and healthcare providers with the necessary basic information to develop integrative medicine systems suited to firefighters.
Assuntos
Bombeiros , Incêndios , Traumatismos Ocupacionais , Humanos , Pesquisa Qualitativa , República da CoreiaRESUMO
Non-steroidal anti-inflammatory drugs cause gastric ulceration through a number of mechanisms including inhibition of PG synthesis, generation of reactive oxygen species (ROS) and induction of apoptosis. Recently, matrix metalloproteinases (MMP) have been suggested to play a crucial role in these mechanisms. The present study investigated the protective effect of anthocyanins isolated from black rice bran (Heugjinjubyeo) against naproxen-induced gastric mucosal injury in rats. The oral administration of anthocyanins (5, 25 or 50 mg/kg body weight) showed significant protection against naproxen (80 mg/kg body weight)-induced gastric ulcer and inhibited lipid peroxidation in the gastric mucosa. In addition, pretreatment with anthocyanins resulted in a significant increase in the activities of radical-scavenging enzymes such as superoxide dismutase, catalase and glutathione peroxidase. Also biochemical and zymographic analyses suggested that the administration of anthocyanins gives a significant protection against naproxen-induced gastric antral ulcer through scavenging ROS and regulation of matrix metalloproteinase-2 (MMP-2) activity. The results of intracellular radical activation show that anthocyanins suppress the generation of intracellular ROS and attenuate the suppression of MMP-2 activity by naproxen. These results suggest that anthocyanins extracted from black rice may offer potential remedy of gastric antral ulceration.
Assuntos
Antocianinas/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Úlcera Gástrica/metabolismo , Úlcera Gástrica/prevenção & controle , Animais , Antocianinas/isolamento & purificação , Anti-Inflamatórios não Esteroides/toxicidade , Antiulcerosos/isolamento & purificação , Antiulcerosos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Naproxeno/toxicidade , Oryza/química , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/genética , Fator de Necrose Tumoral alfa/genéticaRESUMO
The essential actin-binding factor profilin-1 (Pfn1) is a non-classical tumor suppressor with the abilities toboth inhibit cellular proliferation and augment chemotherapy-induced apoptosis. Besides actin, Pfn1 interacts with proteins harboring the poly-L-proline (PLP) motifs. Our recent work demonstrated that both nuclear localization and PLP-binding are required for tumor growth inhibition by Pfn1, and this is at least partially due to Pfn1 association with the PLP-containing ENL protein in the Super Elongation Complex (SEC) and the transcriptional inhibition of pro-cancer genes. In this paper, by identifying a phosphorylation event of Pfn1 at Ser71 capable of inhibiting its actin-binding and nuclear export, we provide in vitro and in vivo evidence that chemotherapy-induced apoptotic sensitization by Pfn1 requires its cytoplasmic localization and actin-binding. With regard to tumor growth inhibition byPfn1, our data indicate a requirement for dynamic actin association and dissociation rendered by reversible Ser71phosphorylation and dephosphorylation. Furthermore, genetic and pharmacological experiments showed that Ser71 of Pfn1 can be phosphorylated by protein kinase A (PKA). Taken together, our data provide novel mechanistic insights into the multifaceted anticancer activities of Pfn1 and how they are spatially-defined in the cell and differentially regulated by ligand-binding.
RESUMO
Aberrant expression of nuclear transporters and deregulated subcellular localization of their cargo proteins are emerging as drivers and therapeutic targets of cancer. Here, we present evidence that the nuclear exporter exportin-6 and its cargo profilin-1 constitute a functionally important and frequently deregulated axis in cancer. Exportin-6 upregulation occurs in numerous cancer types and is associated with poor patient survival. Reducing exportin-6 level in breast cancer cells triggers antitumor effects by accumulating nuclear profilin-1. Mechanistically, nuclear profilin-1 interacts with eleven-nineteen-leukemia protein (ENL) within the super elongation complex (SEC) and inhibits the ability of the SEC to drive transcription of numerous pro-cancer genes including MYC. XPO6 and MYC are positively correlated across diverse cancer types including breast cancer. Therapeutically, exportin-6 loss sensitizes breast cancer cells to the bromodomain and extra-terminal (BET) inhibitor JQ1. Thus, exportin-6 upregulation is a previously unrecognized cancer driver event by spatially inhibiting nuclear profilin-1 as a tumor suppressor.
Assuntos
Carioferinas/metabolismo , Neoplasias/metabolismo , Profilinas/antagonistas & inibidores , Profilinas/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Carioferinas/genética , Células MCF-7 , Camundongos , Camundongos Nus , Neoplasias/genética , Profilinas/genética , Análise de Sobrevida , Regulação para CimaRESUMO
We conducted a molecular epizootiological study of infectious bursal disease (IBD) in Korea by analyzing 85 IBD viruses (IBDVs) obtained from vaccinated or unvaccinated flocks between 1980 and 2007. Phylogenetic analysis of the partial nucleotide sequence of the hypervariable region of the VP2 gene (nucleotides 661-1020) and pathogenicity tests revealed more genetic and phenotypic diversity of IBDV in Korea than has been reported previously. We showed that very virulent IBDVs (vvIBDVs) were already present in Korea in 1986. Moreover, vvIBDVs were repeatedly detected in Korean poultry that had been vaccinated, which casts doubt on the IBD vaccine programs. We also identified novel putative antigenic variant (AV)-like IBDV isolates on the basis of their antigenic indices and the presence of amino acid changes (P222S or P222T-A321D) that are known to affect the antigenicity of VP2. These observations suggest that future studies examining the efficacy of conventional vaccines against atrophy of the bursa of Fabricius and vvIBDV shedding may be useful. Moreover, it will be of interest to determine the prevalence of putative Korean antigenic variants and whether these strains exert immunosuppressive effects in vaccinated birds.
Assuntos
Infecções por Birnaviridae/veterinária , Variação Genética , Vírus da Doença Infecciosa da Bursa/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Animais , Antígenos Virais/genética , Infecções por Birnaviridae/epidemiologia , Infecções por Birnaviridae/virologia , Galinhas , Vírus da Doença Infecciosa da Bursa/genética , Vírus da Doença Infecciosa da Bursa/patogenicidade , Coreia (Geográfico)/epidemiologia , Epidemiologia Molecular , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Doenças das Aves Domésticas/virologia , RNA Viral/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Proteínas Estruturais Virais/genéticaRESUMO
Fifty-six Newcastle disease virus strains collected from 2000 to 2006 could be grouped into subgenotype VIId. However, they displayed cumulative mutations in and around the linear epitope of hemagglutinin-neuraminidase (residues 345 to 353) with time. The antigenicities of the variants that became predominant in Korea differ from each other and from the wild type.
Assuntos
Variação Antigênica , Epitopos/genética , Variação Genética , Proteína HN/genética , Vírus da Doença de Newcastle/imunologia , Sequência de Aminoácidos , Animais , Galinhas/virologia , Epitopos/química , Epitopos/imunologia , Proteína HN/química , Proteína HN/imunologia , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Peptídeos/síntese química , Peptídeos/química , Peptídeos/imunologia , Doenças das Aves Domésticas/virologia , Análise de Sequência de DNA , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/genéticaRESUMO
PhiSG-JL2 is a newly discovered lytic bacteriophage infecting Salmonella enterica serovar Gallinarum biovar Gallinarum but is nonlytic to a rough vaccine strain of serovar Gallinarum biovar Gallinarum (SG-9R), S. enterica serovar Enteritidis, S. enterica serovar Typhimurium, and S. enterica serovar Gallinarum biovar Pullorum. The phiSG-JL2 genome is 38,815 bp in length (GC content, 50.9%; 230-bp-long direct terminal repeats), and 55 putative genes may be transcribed from the same strand. Functions were assigned to 30 genes based on high amino acid similarity to known proteins. Most of the expected proteins except tail fiber (31.9%) and the overall organization of the genomes were similar to those of yersiniophage phiYeO3-12. phiSG-JL2 could be classified as a new T7-like virus and represents the first serovar Gallinarum biovar Gallinarum phage genome to be sequenced. On the basis of intraspecific ratios of nonsynonymous to synonymous nucleotide changes (Pi[a]/Pi[s]), gene 2 encoding the host RNA polymerase inhibitor displayed Darwinian positive selection. Pretreatment of chickens with phiSG-JL2 before intratracheal challenge with wild-type serovar Gallinarum biovar Gallinarum protected most birds from fowl typhoid. Therefore, phiSG-JL2 may be useful for the differentiation of serovar Gallinarum biovar Gallinarum from other Salmonella serotypes, prophylactic application in fowl typhoid control, and understanding of the vertical evolution of T7-like viruses.
Assuntos
Podoviridae/genética , Podoviridae/isolamento & purificação , Salmonella enterica/virologia , Animais , Composição de Bases , Galinhas , DNA Viral/química , DNA Viral/genética , Ordem dos Genes , Genes Virais , Genoma Viral , Dados de Sequência Molecular , Fases de Leitura Aberta , Podoviridae/crescimento & desenvolvimento , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/prevenção & controle , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Análise de Sobrevida , Sintenia , Sequências Repetidas Terminais , Febre Tifoide/prevenção & controle , Proteínas Virais/genéticaRESUMO
Fowl typhoid is a disease of adult chickens and is caused by Salmonella Gallinarum infection via the alimentary tract. The experimental reproduction of fowl typhoid per os (PO) requires artificial conditions to minimize the effect of gastric acid, and several Salmonella serovars have been known to be transmitted via the respiratory route. Therefore, we have hypothesized the existence of a respiratory route for Salmonella Gallinarum infection and have attempted to reproduce fowl typhoid via intratracheal challenge. In accordance with our hypothesis, the intratracheal challenges of Salmonella Gallinarum reproduced exactly same lesions as fowl typhoid and induced higher mortality and morbidity than those of the PO challenge. Therefore, this study represents the first reproduction of fowl typhoid via respiratory route, and our findings may be useful for understanding the transmission of Salmonella Gallinarum in the field.
Assuntos
Galinhas/microbiologia , Doenças das Aves Domésticas/microbiologia , Sistema Respiratório/microbiologia , Salmonelose Animal/microbiologia , Salmonella/classificação , Animais , Galinhas/genética , MasculinoRESUMO
The integron is a mobile gene element which harbors antibiotic-resistance gene cassettes capable of site-specific integration. Among the four known types of integrons, the class 1 integron has been associated with multidrug-resistance in pathogenic bacteria. These gene cassettes have been the focus of a series of studies. The gene cassettes share a common promoter, and their expression levels are affected not only by their proximity to the promoter, but also by the strength (weak, hybrid and strong) of the common promoter, P1, as well as the presence of the additional promoter, P2. In this study, we developed molecular methods for the differentiation of promoter structures using PCR, restriction enzyme analysis, and polyacrylamide gel electrophoresis, and have applied them to the characterization of class 1 integrons in 33 non-typhoidal Salmonella serotypes in Korea. Class 1 integrons were detected in four serotypes: S. Derby (SD), S. Istanbul (SI), S. Paratyphi B (SPB), and S. Livingstone (SL), and the amplicon sizes were 1.0 Kb (SD, SI and SPB) and 2.0 Kb (SL). All of the 1.0 kb amplicons harbored gene cassettes (aadA1 or aadA2), but the 2.0 kb amplicon harbored three (dhfrXII-orfF-aadA2) gene cassettes, which conferred streptomycin/spectinomycin (aadA) and trimethoprim (dhfr) resistances. Our promoter structure study revealed three types of promoters; strong P1 (SD), weak P1 (SPB and SL), and weak P1+P2 (SI). In conclusion, the class 1 integrons were detected in Korean NTS, and their promoter structures were found to be variable. Therefore, our methods may prove helpful in terms of our understanding of molecular diversity, as well as the transmission of class 1 integrons and phenotype-genotype relationships in antibiotic-resistance.
Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Integrons/genética , Regiões Promotoras Genéticas , Mapeamento por Restrição/métodos , Salmonella enterica/classificação , Antibacterianos/farmacologia , Sequência de Bases , Farmacorresistência Bacteriana/genética , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , SorotipagemRESUMO
A one-step reverse transcriptase-polymerase chain reaction (RT-PCR) method was developed and optimized for the detection of duck hepatitis virus type 1 (DHV-1) using the Viral Gene-spin viral DNA/RNA extraction kit. A pair of DHV-1-specific primers was designed against the gene encoding RNA-dependent RNA polymerase (3D gene). Using RNA prepared from duckling liver samples infected with two reference and seven Korean field isolates of DHV-1, one-step RT-PCR with DHV1-specific primers amplified a 467-bp fragment. Under the same conditions, no amplification was observed for 14 other avian pathogenic viruses and bacteria. Using RNA prepared from serial dilutions of the DHV-1 with the supernatant of the uninfected duckling liver homogenate (10% w/v), the one-step RT-PCR assay was found to be sensitive to 10 50% egg lethal dose (ELD50) 0.1 ml(-1) of DHV-1. Furthermore, this method detected DHV-1 from the livers and allantoic fluid of duck embryos dying before 3 days postinoculation (PI) and of chicken embryos that were chilled at 3 days PI. Therefore, this one-step RT-PCR method is rapid, sensitive, and reliable, and can be readily adapted for detection of DHV-1 from other clinical samples.
Assuntos
Vírus da Hepatite do Pato/genética , Vírus da Hepatite do Pato/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Animais , Sequência de Bases , Patos/embriologia , Patos/virologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e EspecificidadeRESUMO
UBE2O is localized in the 17q25 locus, which is known to be amplified in human cancers, but its role in tumorigenesis remains undefined. Here we show that Ube2o deletion in MMTV-PyVT or TRAMP mice profoundly impairs tumor initiation, growth, and metastasis, while switching off the metabolic reprogramming of tumor cells. Mechanistically, UBE2O specifically targets AMPKα2 for ubiquitination and degradation, and thereby promotes activation of the mTOR-HIF1α pathway. Notably, inactivation of AMPKα2, but not AMPKα1, abrogates the tumor attenuation caused by UBE2O loss, while treatment with rapamycin or inhibition of HIF1α ablates UBE2O-dependent tumor biology. Finally, pharmacological blockade of UBE2O inhibits tumorigenesis through the restoration of AMPKα2, suggesting the UBE2O-AMPKα2 axis as a potential cancer therapeutic target.
Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Neoplasias/etiologia , Enzimas de Conjugação de Ubiquitina/fisiologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Antígenos de Neoplasias/metabolismo , Progressão da Doença , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Serina-Treonina Quinases TOR/fisiologia , Enzimas de Conjugação de Ubiquitina/antagonistas & inibidores , UbiquitinaçãoRESUMO
Salmonella gallinarum is gram-negative bacteria that cause fowl typhoid (FT) in chickens. Since the first outbreak of FT reported in 1992 in Korea, it has widely spread throughout the country. Today, FT is one of the most devastating diseases of poultry. The aim of the present study was to ascertain a genetic relationship among S. gallinarum isolates collected from different regions of Korea over a 10-year period. We examined a total of 38 isolates of S. gallinarum obtained in 29 regions of Korea from 1992 to 2001 including the 9R vaccine strain and the standard strain of S. gallinarum (ATCC 9184). The PFGE profiles produced 12 different patterns with the XbaI-digestion and 11 different patterns with the SpeI-digestion. The RAPD using URP-6 primers showed eight different genotypes with the same Salmonella isolates. The PFGE patterns of the 9R vaccine strain and ATCC 9184 of S. gallinarum were different from the identical type A, the most common genotype among field isolates in our study. In conclusion, a low genetic heterogeneity was observed among Korean S. gallinarum isolates. In addition, PFGE appeared to be a more accurate and reproducible method for genotyping of S. gallinarum isolates than RAPD.
Assuntos
Galinhas , Eletroforese em Gel de Campo Pulsado/veterinária , Doenças das Aves Domésticas/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico/veterinária , Salmonelose Animal/microbiologia , Salmonella/classificação , Animais , Análise por Conglomerados , DNA Bacteriano/análise , Eletroforese em Gel de Campo Pulsado/métodos , Genótipo , Coreia (Geográfico) , Filogenia , Doenças das Aves Domésticas/diagnóstico , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Reprodutibilidade dos Testes , Salmonella/genética , Salmonelose Animal/diagnóstico , Sensibilidade e EspecificidadeRESUMO
Salmonella enterica subspecies enterica serovar Gallinarum biovar Gallinarum is the causative agent of fowl typhoid in chickens, outbreaks of which have devastated poultry populations in Korea since 1992. In order to identify genetic differences among S. Gallinarum isolates, bacteria were examined using the random amplified polymorphic DNA (RAPD) method. Of 13 arbitrary primers screened initially, the primer designated as universal rice primer-6 (URP-6) was selected for subsequent typing assays because it produced a distinctive and reproducible DNA fingerprint for a S. Gallinarum reference strain. URP-6-based RAPD analysis assigned 30 S. Gallinarum isolates into 6 types, with 26 isolates (86.6%) belonging to 2 major RAPD types. The distribution of virulence genes in S. Gallinarum isolates was examined by Southern hybridization. All tested isolates had the invasion gene, invA, the virulence plasmid gene, spvB, and the S. Enteritidis fimbrial gene, sefC. The distribution of virulence genes among S. Gallinarum isolates did not correlate with any specific RAPD type.
Assuntos
Técnicas de Tipagem Bacteriana/métodos , Genes Bacterianos/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico/veterinária , Salmonella enterica/genética , Salmonella enterica/patogenicidade , Fatores de Virulência/genética , Variação Genética , Genótipo , Salmonella enterica/classificação , Virulência/genéticaRESUMO
The role of AMP-activated protein kinase (AMPK) in promoting fatty acid (FA) oxidation in various tissues, such as liver and muscle, has been well understood. However, the role of AMPK in lipolysis and FA metabolism in adipose tissue has been controversial. To investigate the role of AMPK in the regulation of adipose lipolysis in vivo, we generated mice with adipose-tissue-specific knockout of both the α1 and α2 catalytic subunits of AMPK (AMPK-ASKO mice) by using aP2-Cre and adiponectin-Cre. Both models of AMPK-ASKO ablation show no changes in desnutrin/ATGL levels but have defective phosphorylation of desnutrin/ATGL at S406 to decrease its triacylglycerol (TAG) hydrolase activity, lowering basal lipolysis in adipose tissue. These mice also show defective phosphorylation of hormone-sensitive lipase (HSL) at S565, with higher phosphorylation at protein kinase A sites S563 and S660, increasing its hydrolase activity and isoproterenol-stimulated lipolysis. With higher overall adipose lipolysis, both models of AMPK-ASKO mice are lean, having smaller adipocytes with lower TAG and higher intracellular free-FA levels. Moreover, FAs from higher lipolysis activate peroxisome proliferator-activated receptor delta to induce FA oxidative genes and increase FA oxidation and energy expenditure. Overall, for the first time, we provide in vivo evidence of the role of AMPK in the phosphorylation and regulation of desnutrin/ATGL and HSL and thus adipose lipolysis.
Assuntos
Proteínas Quinases Ativadas por AMP/genética , Ácidos Graxos/metabolismo , Lipase/metabolismo , Esterol Esterase/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo/metabolismo , Animais , Técnicas de Inativação de Genes , Metabolismo dos Lipídeos , Lipólise , Camundongos , Oxirredução , FosforilaçãoRESUMO
Shikonin, which derives from Lithospermum erythrorhizon, has been traditionally used against a variety of diseases, including cancer, in Eastern Asia. Here we determined that shikonin inhibits proliferation of gastric cancer cells by inducing apoptosis. Shikonin's biological activity was validated by observing cell viability, caspase 3 activity, reactive oxygen species (ROS) generation, and apoptotic marker expressions in AGS stomach cancer cells. The concentration range of shikonin was 35-250 nM with the incubation time of 6 h. Protein levels of Nrf2 and p53 were evaluated by western blotting and confirmed by real-time PCR. Our results revealed that shikonin induced the generation of ROS as well as caspase 3-dependent apoptosis. c-Jun-N-terminal kinases (JNK) activity was significantly elevated in shikonin-treated cells, thereby linking JNK to apoptosis. Furthermore, our results revealed that shikonin induced p53 expression but repressed Nrf2 expression. Moreover, our results suggested that there may be a co-regulation between p53 and Nrf2, in which transfection with siNrf2 induced the p53 expression. We demonstrated for the first time that shikonin activated cell apoptosis in AGS cells via caspase 3- and JNK-dependent pathways, as well as through the p53-Nrf2 mediated signal pathway. Our study validates in partly the contribution of shikonin as a new therapeutic approaches/ agent for cancer chemotherapy.