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BACKGROUND & AIMS: We reported that cholangiocyte senescence, regulated by the transcription factor ETS proto-oncogene 1 (ETS1), is a pathogenic feature of primary sclerosing cholangitis (PSC). Furthermore, histone 3 lysine 27 is acetylated at senescence-associated loci. The epigenetic readers, bromodomain and extra-terminal domain (BET) proteins, bind acetylated histones, recruit transcription factors, and drive gene expression. Thus, we tested the hypothesis that BET proteins interact with ETS1 to drive gene expression and cholangiocyte senescence. METHODS: We performed immunofluorescence for BET proteins (BRD2 and 4) in liver tissue from liver tissue from PSC patients and a mouse PSC model. Using normal human cholangiocytes (NHCs), NHCs experimentally induced to senescence (NHCsen), and PSC patient-derived cholangiocytes (PSCDCs), we assessed senescence, fibroinflammatory secretome, and apoptosis after BET inhibition or RNA interference depletion. We assessed BET interaction with ETS1 in NHCsen and tissues from PSC patient, and the effects of BET inhibitors on liver fibrosis, senescence, and inflammatory gene expression in mouse models. RESULTS: Tissue from patients with PSC and a mouse PSC model exhibited increased cholangiocyte BRD2 and 4 protein (â¼5×) compared with controls without disease. NHCsen exhibited increased BRD2 and 4 (â¼2×), whereas PSCDCs exhibited increased BRD2 protein (â¼2×) relative to NHC. BET inhibition in NHCsen and PSCDCs reduced senescence markers and inhibited the fibroinflammatory secretome. ETS1 interacted with BRD2 in NHCsen, and BRD2 depletion diminished NHCsen p21 expression. BET inhibitors reduced senescence, fibroinflammatory gene expression, and fibrosis in the 3,5-diethoxycarbonyl-1,4-dihydrocollidine-fed and Mdr2-/- mouse models. CONCLUSION: Our data suggest that BRD2 is an essential mediator of the senescent cholangiocyte phenotype and is a potential therapeutic target for patients with PSC.
Assuntos
Colangite Esclerosante , Animais , Camundongos , Humanos , Colangite Esclerosante/patologia , Fígado/patologia , Regulação da Expressão Gênica , Histonas/metabolismo , Proto-Oncogenes , Epigênese GenéticaRESUMO
Transforming growth factor-beta (TGFß) is an enigmatic protein with various roles in healthy tissue homeostasis/development as well as the development or progression of cancer, wound healing, fibrotic disorders, and immune modulation, to name a few. As TGFß is causal to various fibroproliferative disorders featuring localized or systemic tissue/organ fibrosis as well as the activated stroma observed in various malignancies, characterizing the pathways and players mediating its action is fundamental. In the current study, we found that TGFß induces the expression of the immunoinhibitory molecule Programed death-ligand 1 (PD-L1) in human and murine fibroblasts in a Smad2/3- and YAP/TAZ-dependent manner. Furthermore, PD-L1 knockdown decreased the TGFß-dependent induction of extracellular matrix proteins, including collagen Iα1 (colIα1) and alpha-smooth muscle actin (α-SMA), and cell migration/wound healing. In addition to an endogenous role for PD-L1 in profibrotic TGFß signaling, TGFß stimulated-human lung fibroblast-derived PD-L1 into extracellular vesicles (EVs) capable of inhibiting T cell proliferation in response to T cell receptor stimulation and mediating fibroblast cell migration. These findings provide new insights and potential targets for a variety of fibrotic and malignant diseases.
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Antígeno B7-H1/biossíntese , Vesículas Extracelulares/metabolismo , Fibroblastos/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Células 3T3 , Animais , Antígeno B7-H1/genética , Vesículas Extracelulares/patologia , Fibroblastos/patologia , Fibrose , Regulação da Expressão Gênica , Humanos , Camundongos , Fator de Crescimento Transformador beta/genéticaRESUMO
In the current work we show that the profibrotic actions of TGF-ß are mediated, at least in part, through a metabolic maladaptation in glutamine metabolism and how the inhibition of glutaminase 1 (GLS1) reverses pulmonary fibrosis. GLS1 was found to be highly expressed in fibrotic vs normal lung fibroblasts and the expression of profibrotic targets, cell migration, and soft agar colony formation stimulated by TGF-ß required GLS1 activity. Moreover, knockdown of SMAD2 or SMAD3 as well as inhibition of PI3K, mTORC2, and PDGFR abrogated the induction of GLS1 by TGF-ß. We further demonstrated that the NAD-dependent protein deacetylase, SIRT7, and the FOXO4 transcription factor acted as endogenous brakes for GLS1 expression, which are inhibited by TGF-ß. Lastly, administration of the GLS1 inhibitor CB-839 attenuated bleomycin-induced pulmonary fibrosis. Our study points to an exciting and unexplored connection between epigenetic and transcriptional processes that regulate glutamine metabolism and fibrotic development in a TGF-ß-dependent manner.
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Fibroblastos/patologia , Regulação da Expressão Gênica , Glutaminase/metabolismo , Fibrose Pulmonar/patologia , Sirtuínas/metabolismo , Fator de Crescimento Transformador beta/toxicidade , Animais , Antibióticos Antineoplásicos/toxicidade , Bleomicina/toxicidade , Movimento Celular , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Glutaminase/genética , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Transdução de Sinais , Sirtuínas/genética , Proteínas Smad/genética , Proteínas Smad/metabolismoRESUMO
Pathogenic fibrotic diseases, including idiopathic pulmonary fibrosis (IPF), have some of the worst prognoses and affect millions of people worldwide. With unclear etiology and minimally effective therapies, two-thirds of IPF patients die within 2-5 years from this progressive interstitial lung disease. Transforming Growth Factor Beta (TGFß) and insulin-like growth factor-1 (IGF-1) are known to promote fibrosis; however, myofibroblast specific upregulation of IGF-1 in the initiation and progression of TGFß-induced fibrogenesis and IPF have remained unexplored. To address this, the current study (1) documents the upregulation of IGF-1 via TGFß in myofibroblasts and fibrotic lung tissue, as well as its correlation with decreased pulmonary function in advanced IPF; (2) identifies IGF-1's C1 promoter as mediating the increase in IGF-1 transcription by TGFß in pulmonary fibroblasts; (3) determines that SMAD2 and mTOR signaling are required for TGFß-dependent Igf-1 expression in myofibroblasts; (4) demonstrates IGF-1R activation is essential to support TGFß-driven profibrotic myofibroblast functions and excessive wound healing; and (5) establishes the effectiveness of slowing the progression of murine lung fibrosis with the IGF-1R inhibitor OSI-906. These findings expand our knowledge of IGF-1's role as a novel fibrotic-switch, bringing us one step closer to understanding the complex biological mechanisms responsible for fibrotic diseases and developing effective therapies.
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Antibióticos Antineoplásicos/toxicidade , Bleomicina/toxicidade , Fibroblastos/patologia , Fibrose Pulmonar Idiopática/patologia , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Animais , Diferenciação Celular , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/metabolismo , Fator de Crescimento Insulin-Like I/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Evidence is provided that the fibroproliferative actions of TGF-ß are dependent on a metabolic adaptation that sustains pathologic growth. Specifically, profibrotic TGF-ß signaling is shown to require fatty acid synthase (FASN), an essential anabolic enzyme responsible for the de novo synthesis of fatty acids. With the use of pharmacologic and genetic approaches, we show that TGF-ß-stimulated FASN expression is independent of Smad2/3 and is mediated via mammalian target of rapamycin complex 1. In the absence of FASN activity or protein, TGF-ß-driven fibrogenic processes are reduced with no apparent toxicity. Furthermore, as increased FASN expression was also observed to correlate with the degree of lung fibrosis in bleomycin-treated mice, inhibition of FASN was examined in a murine-treatment model of pulmonary fibrosis. Remarkably, inhibition of FASN not only decreased expression of profibrotic targets, but lung function was also stabilized/improved, as assessed by peripheral blood oxygenation.-Jung, M.-Y., Kang, J.-H., Hernandez, D. M., Yin, X., Andrianifahanana, M., Wang, Y., Gonzalez-Guerrico, A., Limper, A. H., Lupu, R., Leof, E. B. Fatty acid synthase is required for profibrotic TGF-ß signaling.
Assuntos
Ácido Graxo Sintase Tipo I/metabolismo , Fibrose Pulmonar/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Bleomicina/toxicidade , Linhagem Celular , Ácido Graxo Sintase Tipo I/genética , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/etiologia , Transdução de Sinais , Proteínas Smad/metabolismoRESUMO
TGF-ß plays a central role in the pathogenesis of fibroproliferative disorders. Defining the exact underlying molecular basis is therefore critical for the development of viable therapeutic strategies. Here, we show that expression of the facilitative glucose transporter 1 (GLUT1) is induced by TGF-ß in fibroblast lines and primary cells and is required for the profibrotic effects of TGF-ß. In addition, enhanced GLUT1 expression is observed in fibrotic areas of lungs of both patients with idiopathic pulmonary fibrosis and mice that are subjected to a fibrosis-inducing bleomycin treatment. By using pharmacologic and genetic approaches, we demonstrate that up-regulation of GLUT1 occurs via the canonical Smad2/3 pathway and requires autocrine activation of the receptor tyrosine kinases, platelet-derived and epidermal growth factor receptors. Engagement of the common downstream effector PI3K subsequently triggers activation of the MEK and mammalian target of rapamycin complex 2, which cooperate in regulating GLUT1 expression. Of note, inhibition of GLUT1 activity and/or expression is shown to impair TGF-ß-driven fibrogenic processes, including cell proliferation and production of profibrotic mediators. These findings provide new perspectives on the interrelation of metabolism and profibrotic TGF-ß signaling and present opportunities for potential therapeutic intervention.-Andrianifahanana, M., Hernandez, D. M., Yin, X., Kang, J.-H., Jung, M.-Y., Wang, Y., Yi, E. S., Roden, A. C., Limper, A. H., Leof, E. B. Profibrotic up-regulation of glucose transporter 1 by TGF-ß involves activation of MEK and mammalian target of rapamycin complex 2 pathways.
Assuntos
Proliferação de Células/fisiologia , Transportador de Glucose Tipo 1/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Sirolimo/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibroblastos/metabolismo , Fibrose/metabolismo , Pulmão/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia , Regulação para CimaRESUMO
IL-33 is elevated in afflicted tissues of patients with mast cell (MC)-dependent chronic allergic diseases. Based on its acute effects on mouse MCs, IL-33 is thought to play a role in the pathogenesis of allergic disease through MC activation. However, the manifestations of prolonged IL-33 exposure on human MC function, which best reflect the conditions associated with chronic allergic disease, are unknown. In this study, we found that long-term exposure of human and mouse MCs to IL-33 results in a substantial reduction of MC activation in response to Ag. This reduction required >72 h exposure to IL-33 for onset and 1-2 wk for reversion following IL-33 removal. This hyporesponsive phenotype was determined to be a consequence of MyD88-dependent attenuation of signaling processes necessary for MC activation, including Ag-mediated calcium mobilization and cytoskeletal reorganization, potentially as a consequence of downregulation of the expression of phospholipase Cγ(1) and Hck. These findings suggest that IL-33 may play a protective, rather than a causative, role in MC activation under chronic conditions and, furthermore, reveal regulated plasticity in the MC activation phenotype. The ability to downregulate MC activation in this manner may provide alternative approaches for treatment of MC-driven disease.
Assuntos
Terapia de Imunossupressão , Interleucinas/imunologia , Mastócitos/imunologia , Mastócitos/metabolismo , Fenótipo , Actinas/metabolismo , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33 , Interleucinas/farmacologia , Mastócitos/efeitos dos fármacos , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Fosfolipase C gama/genética , Fosfolipase C gama/imunologia , Fosfolipase C gama/metabolismo , Multimerização Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-hck/genética , Proteínas Proto-Oncogênicas c-hck/imunologia , Receptores de Interleucina/genética , Receptores de Interleucina/imunologiaRESUMO
Very few studies have examined the effects of both religious affiliation and religiosity on mortality at the same time, and studies employing multiple dimensions of religiosity other than religious attendance are rare. Using the newly created General Social Survey-National Death Index data, our report contributes to the religion and mortality literature by examining religious affiliation and religiosity at the same time. Compared to Mainline Protestants, Catholics, Jews, and other religious groups have lower risk of death, but Black Protestants, Evangelical Protestants, and even those with no religious affiliation are not different from Mainline Protestants. While our study is consistent with previous findings that religious attendance leads to a reduction in mortality, we did not find other religious measures, such as strength of religious affiliation, frequency of praying, belief in an afterlife, and belief in God to be associated with mortality. We also find interaction effects between religious affiliation and attendance. The lowest mortality of Jews and other religious groups is more apparent for those with lower religious attendance. Thus, our result may emphasize the need for other research to focus on the effects of religious group and religious attendance on mortality at the same time.
Assuntos
Mortalidade , Religião , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Catolicismo , Cristianismo , Feminino , Humanos , Judeus/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , ProtestantismoRESUMO
Autophagy can be activated via MTORC1 down-regulation by amino acid deprivation and by certain chemicals such as rapamycin, torin, and niclosamide. Lysosome is the degrading machine for autophagy but has also been linked to MTORC1 activation through the Rag/RRAG GTPase pathway. This association raises the question of whether lysosome can be involved in the initiation of autophagy. Toward this end, we found that niclosamide, an MTORC1 inhibitor, was able to inhibit lysosome degradation and increase lysosomal permeability. Niclosamide was ineffective in inhibiting MTORC1 in cells expressing constitutively activated Rag proteins, suggesting that its inhibitory effects were targeted to the Rag-MTORC1 signaling system. This places niclosamide in the same category of bafilomycin A1 and concanamycin A, inhibitors of the vacuolar H(+)-ATPase, for its dependence on Rag GTPase in suppression of MTORC1. Surprisingly, classical lysosome inhibitors such as chloroquine, E64D, and pepstatin A were also able to inhibit MTORC1 in a Rag-dependent manner. These lysosome inhibitors were able to activate early autophagy events represented by ATG16L1 and ATG12 puncta formation. Our work established a link between the functional status of the lysosome in general to the Rag-MTORC1 signaling axis and autophagy activation. Thus, the lysosome is not only required for autophagic degradation but also affects autophagy activation. Lysosome inhibitors can have a dual effect in suppressing autophagy degradation and in initiating autophagy.
Assuntos
Autofagia/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Complexos Multiproteicos/metabolismo , Niclosamida/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidoresRESUMO
In malignant glioma, cytotoxic drugs are often inhibited from accessing the tumor site due to the blood-tumor barrier (BTB). Ibrutinib, FDA-approved lymphoma agent, inhibits Bruton tyrosine kinase (BTK) and has previously been shown to independently impair aortic endothelial adhesion and increase rodent glioma model survival in combination with cytotoxic therapy. Yet additional research is required to understand ibrutinib's effect on BTB function. In this study, we detail baseline BTK expression in glioma cells and its surrounding vasculature, then measure endothelial junctional expression/function changes with varied ibrutinib doses in vitro. Rat glioma cells and rodent glioma models were treated with ibrutinib alone (1-10 µM and 25 mg/kg) and in combination with doxil (10-100 µM and 3 mg/kg) to assess additive effects on viability, drug concentrations, tumor volume, endothelial junctional expression and survival. We found that ibrutinib, in a dose-dependent manner, decreased brain endothelial cell-cell adhesion over 24 h, without affecting endothelial cell viability (p < 0.005). Expression of tight junction gene and protein expression was decreased maximally 4 h after administration, along with inhibition of efflux transporter, ABCB1, activity. We demonstrated an additive effect of ibrutinib with doxil on rat glioma cells, as seen by a significant reduction in cell viability (p < 0.001) and increased CNS doxil concentration in the brain (56 ng/mL doxil alone vs. 74.6 ng/mL combination, p < 0.05). Finally, Ibrutinib, combined with doxil, prolonged median survival in rodent glioma models (27 vs. 16 days, p < 0.0001) with brain imaging showing a - 53% versus - 75% volume change with doxil alone versus combination therapy (p < 0.05). These findings indicate ibrutinib's ability to increase brain endothelial permeability via junctional disruption and efflux inhibition, to increase BTB drug entry and prolong rodent glioma model survival. Our results motivate the need to identify other BTB modifiers, all with the intent of improving survival and reducing systemic toxicities.
Assuntos
Adenina/análogos & derivados , Antineoplásicos , Doxorrubicina/análogos & derivados , Glioma , Piperidinas , Ratos , Animais , Roedores , Glioma/patologia , Antineoplásicos/uso terapêutico , Barreira Hematoencefálica/patologia , PolietilenoglicóisRESUMO
BACKGROUND: Bee venom has been used to relieve pain and to treat inflammatory diseases, including rheumatoid arthritis, in humans. To better understand the mechanisms of the anti-inflammatory and anti-atherosclerosis effect of bee venom, gel electrophoresis and mass spectrometry were used to identify proteins whose expression was altered in human Vascular Smooth Muscle Cells (hVSMCs) stimulated by tumor necrosis factor alpha after 12 h in the presence of melittin. RESULTS: To obtain valuable insights into the anti-inflammatory and anti-atherosclerosis mechanisms of melittin, two-dimensional (2-D) gel electrophoresis and MALDI-TOF/TOF were used. The proteome study, we showed 33 significant proteins that were differentially expressed in the cells treated with tumor necrosis factor alpha and melittin. Thirteen proteins were significantly increased in the cells treated with tumor necrosis factor alpha, and those proteins were reduced in the cells treated with melittin. Five of the proteins that showed increased expression in the cells treated with tumor necrosis factor alpha are involved in cell migration, including calreticulin, an essential factor of development that plays a role in transcription regulation. The proteins involved in cell migration were reduced in the melittin treated cells. The observed changes in the expression of GRP75, prohibitin, and a select group of other proteins were validated with reverse transcribed-PCR. It was confirmed that the observed change in the protein levels reflected a change in the genes level. In addition, the phosphorylation of EGFR and ERK was validated by analyzing the protein pathway. CONCLUSION: Taken together, these data established that the expression of some proteins was significantly changed by melittin treatment in tumor necrosis factor alpha stimulated the cells and provided insights into the mechanism of the melittin function for its potential use as an anti-inflammatory agent.
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Although having a variety of roles is generally beneficial for mental health, little is known about the relationships between work-family role combinations and depressive symptoms among married women in Korea, where child rearing is strongly considered a mother's responsibility. This study examines how the four types of work-family role combinations may be associated with depressive symptoms among married Korean women younger than 50 years old. Data were collected from 2012 through 2020 in five surveys by the Korean Longitudinal Survey of Women & Families. In total, 4811 married women (14,851 person-period observations) were analyzed using regression models with fixed effects. This enabled estimation of the within-person effects of transitions in work-family role combinations on depressive symptoms. Work-family role combinations were categorized as follows based on whether respondents had a job or at least one child: having both worker and mother roles, having a worker role only, having neither a worker nor a mother role, and having a mother role only. The findings indicate that married women who had only a mother role had more severe depressive symptoms than the other three groups. However, after controlling for whether respondents had a preschool-aged child, only those with both worker and mother roles had significantly lower levels of depressive symptoms compared with those with a mother role only. This study suggests that transitioning to being a working mother from a full-time mother may benefit the mental health of married Korean women. Furthermore, whether married women have a child critically impacts their mental health more than the number of roles. Raising a preschool-aged child seems to potentially be especially stressful for married Korean women. Working outside the home can protect the mental health of married Korean mothers who are affected by the social pressure to immerse themselves in child-rearing.
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Female researchers may have experienced more difficulties than their male counterparts since the COVID-19 outbreak because of gendered housework and childcare. To test it, we constructed a unique dataset that connects 15,280,382 scholarly publications and their 11,828,866 authors retrieved from Microsoft Academic Graph data between 2016 and 2020 to various national characteristics from LinkedIn, Johns Hopkins Coronavirus Resource Center, and Covid-19 Community Mobility Reports from Google. Using the dataset, this study estimated how much the proportion of female authors in academic journals on a global scale changed in 2020 (net of recent yearly trends). We observed a decrease in research productivity for female researchers in 2020, mostly as first authors, followed by last author position. We also identified various factors that amplified the gender gap by dividing the authors' backgrounds into individual, organizational and national characteristics. Female researchers were more vulnerable when they were in their mid-career, affiliated to the least influential organizations, and more importantly from less gender-equal countries with higher mortality and restricted mobility as a result of COVID-19. Our findings suggest that female researchers were not necessarily excluded from but were marginalized in research since the COVID-19 outbreak and we discuss its policy implications.
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In many countries, COVID-19 has made it harder for women to study because they are expected to do more housework and care for children. This article encompasses different data sources that can be used to figure out how the early pandemic of COVID-19 affected the number of studies done by females, in comparison with males. This data is add-on metadata that can be used with raw Microsoft Academic Graph (MAG) from 2016 to 2020 of the Feb 6, 2021 dump. We retrieved open-source metadata from various sources, including LinkedIn, the Johns Hopkins Coronavirus Resource Center, and Google's COVID-19 Community Mobility Reports, and linked bibliographic information to characteristics of the author's environments. It consists of published journals and online preprints, including each author's gender and involvement in the publication, their position through time, the h-index of their institutes, and gender equality in the professional labor market at the country level. For each record of papers, the data also includes the information of the papers, e.g., title and field of study. By gathering this evidence, our data can support the fact diversity in science is more than just the number of active members of different groups. It should also examine minority participation in science. Our data may help scholars understand diversity in science and advance it. The article ``The effect of the COVID-19 pandemic on gendered research productivity and its correlates'' uses this data as the principal source (Kwon, Yun & Kang, 2021).
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Ascochlorin, a non-toxic prenylphenol compound derived from the fungus Ascochyta viciae, has been shown recently to have anti-cancer effects on various human cancer cells. However, the precise molecular mechanism of this anti-cancer activity remains to be elucidated. Here, we investigated the effects of ascochlorin on hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) expression in human epidermoid cervical carcinoma CaSki cells. Ascochlorin inhibited epidermal growth factor (EGF)-induced HIF-1α and VEGF expression through multiple potential mechanisms. First, ascochlorin selectively inhibited HIF-1α expression in response to EGF stimulation, but not in response to hypoxia (1% O(2)) or treatment with a transition metal (CoCl(2)). Second, ascochlorin inhibited EGF-induced ERK-1/2 activation but not AKT activation, both of which play essential roles in EGF-induced HIF-1α protein synthesis. Targeted inhibition of epidermal growth factor receptor (EGFR) expression using an EGFR-specific small interfering RNA (siRNA) diminished HIF-1α expression, which suggested that ascochlorin inhibits HIF-1α expression through suppression of EGFR activation. Finally, we showed that ascochlorin functionally abrogates in vivo tumor angiogenesis induced by EGF in a Matrigel plug assay. Our data suggest that ascochlorin inhibits EGF-mediated induction of HIF-1α expression in CaSki cells, providing a potentially new avenue of development of anti-cancer drugs that target tumor angiogenesis.
Assuntos
Alcenos/farmacologia , Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fenóis/farmacologia , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias do Colo do Útero/metabolismo , Fator A de Crescimento do Endotélio Vascular/fisiologia , Sequência de Bases , Western Blotting , Linhagem Celular Tumoral , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Neovascularização Patológica/prevenção & controle , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Colo do Útero/irrigação sanguínea , Neoplasias do Colo do Útero/patologiaRESUMO
Fibrosis is induced by the excessive and abnormal deposition of extracellular matrix (ECM) with various growth factors in tissues. Transforming growth factor-ß1 (TGF-ß1), the growth factor involved in fibrosis, modulates ECM synthesis and accumulation. TGF-ß1 enhances the production of stimulators of ECM synthesis such as plasminogen activator inhibitor type 1 (PAI-1). As such, PAI-1 expression directly influences the proteolysis, invasion, and accumulation of ECM. It was shown in this study that ascochlorin, a prenylpenl antiobiotic, prevents the expression of profibrotic factors, such as PAI-1 and collagen type I, and that the TGF-ß1-induced PAI-1 promoter activity is inhibited by ascochlorin. Ascochlorin abolishes the phosphorylation of the EGFR-MEK-ERK signaling pathway to regulate the TGF-ß1-induced expression of PAI-1 without the inhibition of TßRII phosphorylation. Furthermore, the MEK inhibitor and EGFR siRNA block PAI-1 expression, and the Raf-1, MEK, and ERK signaling pathways for the regulation of PAI-1 expression. Ascochlorin suppresses the matrix metalloproteinases (MMPs) activity to activate the heparin-binding EGF-like growth factor (HB-EGF), to induce the phosphorylation of EGFR, and the MMPs inhibitor suppresses EGFR phosphorylation and the PAI-1 mRNA levels. These results suggest that ascochlorin prevents the expression of PAI-1 via the inhibition of an EGFR-dependent signal transduction pathway activated by MMPs.
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Alcenos/farmacologia , Receptores ErbB/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Rim/citologia , Fenóis/farmacologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Alcenos/química , Animais , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz , Fenóis/química , Fosforilação/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidores de Proteases/farmacologia , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RatosRESUMO
Macroautophagy is involved in the bulk degradation of long-lived cytosolic proteins and subcellular organelles, which is important for the survival of cells during starvation. To identify potential players of the autophagy process, we subjected HCT116 cells cultured in complete medium and in Earle's balanced salt solution to proteomics analysis. In approximately 1500 protein spots detected, we characterized 52 unique proteins, whose expression levels were significantly changed following starvation. Notably, we found that Annexin A1 was significantly upregulated following starvation at both mRNA and protein levels. Inhibition of Annexin A1 expression with specific siRNA did not alter starvation-induced autophagy as measured by the level of lipidated LC3, but significantly reversed autophagy degradation as measured by the level of p62/SQSTM 1. Thus Annexin A1 seemed to be positively upregulated during starvation to promote autophagic degradation. Overall, the data presented in this study established a expression profile of the proteome in starved cells, which allowed the identification of proteins with potential significance in starvation-induced autophagy.
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Aminoácidos/deficiência , Anexina A1/metabolismo , Autofagia , Proteoma/metabolismo , Anexina A1/genética , Linhagem Celular , Técnicas de Silenciamento de Genes , Humanos , Proteômica , RNA Interferente Pequeno/genéticaRESUMO
BACKGROUND: The purpose of this study was to introduce a combination procedure with double C-shaped skin incision and an adjusted dual-floor burr hole to prevent skin complications on the scalp with deep brain stimulation (DBS) surgery. METHODS: Between March 2000 and March 2010, 504 DBS electrodes were implanted in 268 patients. We included both bilateral and unilateral DBS surgery cases for Parkinson's disease, tremor, pain, obsessive-compulsive disorder and intractable seizure accompanied with cranial and IPG insertion procedure, but excluded motor cortex stimulation, and spinal cord stimulation. We used a straight skin incision in 118 patients, double C-shaped skin incision only in 113 patients since March 2006, and combined a double C-shaped skin incision and dual-floor burr hole in 37 patients since August 2009. We compared scalp wound complications and the height subscale of the Vancouver Scar Scale between previous straight or C-shaped skin incision and the combination procedure. RESULTS: We had eight scalp erosions associated with infection (3.0%) and six disconnection (2.2%) cases among 268 patients. Before the use of the double C-skin incision or adjusted dual-floor burr hole technique, we had 5 (4.2%) scalp erosion cases among 118 patients. With the introduction of the C-shaped incision, only 3 patients (2.7%) developed scalp erosion. However, no patient among 37 patients developed scalp erosion after using both double C-shaped skin incision and dual-floor burr hole technique. Scalp bump measured by the height subscale of the Vancouver Scar Scale was more cosmetic in the combination procedure. CONCLUSION: The combination procedure prevents skin complications associated with DBS surgery, with tensile strength, less impaired vascular supply and better cosmetic outcome. This promising approach prevents unwanted skin complications associated with DBS surgery and improves patient satisfaction.
Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Couro Cabeludo/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Adulto , Idoso , Procedimentos Cirúrgicos Dermatológicos , Eletrodos Implantados/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/etiologia , TrepanaçãoRESUMO
This study investigated whether and how classroom-level bullies' friendship networks, which reflect the popularity of bullies, were associated with the self-esteem of middle school students in the classroom. We analyzed survey data from 2,444 students in 101 classrooms from 22 middle schools in Korea. Respondents reported their friends' and bullies' names from their classroom. For each student, we generated the number of close friends that a respondent reported (outdegree) and the number of classmates who nominated him or her as a close friend (indegree). Bullies' popularity was measured by the sum of all the bullies' indegrees in a classroom. The findings showed that students in a classroom of bullies with larger popularity had a lower level of self-esteem. Moreover, bullies' popularity was harmful to nonvictims' self-esteem as well as victims' self-esteem. This study suggests that even indirect exposure to bullying in a classroom can decrease the self-esteem of nonvictims by leading to negative emotions such as anger, anxiety, fear, and/or guilty feelings.
Assuntos
Bullying , Vítimas de Crime , Feminino , Humanos , Masculino , República da Coreia , Instituições Acadêmicas , EstudantesRESUMO
Transforming growth factor-beta1 (TGF-beta1) has a wide range of biological functions such as the regulation of cell growth, differentiation, and immunological response in various types of cells. Particularly, TGF-beta1 induces plasminogen activator inhibitor-1 (PAI-1) as a major target protein. PAI-1 is associated with fibrosis, thrombosis, and metabolic disorders. In this study, to identify proteins potentially involved in TGF-beta1-induced fibrosis processes, we performed a proteomic analysis of TGF-beta1-induced normal rat kidney cells exposed to ascofuranone (AF). In these cells, we detected 1500 proteins, with 74 differentially expressed proteins identified by MALDI-TOF and reference to the NCBI and Swiss-Prot databases, including PAI-1, peroxisome prdifesator-activated receptor, prohibitin, glutamate formyltransferase, LIM domain protein 1, LASP-1, porphobilinogen deaminase, and peroxiredoxin 2. We also found that AF suppresses expression of profibrotic factors induced by TGF-beta in renal fibroblasts, including matrix proteins and PAI-1. AF was also shown to inhibit selectively phosphorylation of epidermal growth factor receptor, and downstream kinases such as extracellular signal-regulated kinase 1/2 (ERK-1/2). Further ongoing analysis of fibrosis-related proteins will determine AF's potential for application in fibrotic diseases and therapeutics.