RESUMO
There is an urgent need to develop novel drugs to reduce the mortality from severe infectious diseases with the emergence of new pathogens, including Coronavirus disease 2019 (COVID-19). Although current drugs effectively suppress the proliferation of pathogens, immune cell activation, and inflammatory cytokine functions, they cannot completely reduce mortality from severe infections and sepsis. In this study, we focused on the endothelial cell-specific protein, Roundabout 4 (Robo4), which suppresses vascular permeability by stabilizing endothelial cells, and investigated whether enhanced Robo4 expression could be a novel therapeutic strategy against severe infectious diseases. Endothelial-specific overexpression of Robo4 suppresses vascular permeability and reduces mortality in lipopolysaccharide (LPS)-treated mice. Screening of small molecules that regulate Robo4 expression and subsequent analysis revealed that two competitive small mothers against decapentaplegic (SMAD) signaling pathways, activin receptor-like kinase 5 (ALK5)-SMAD2/3 and ALK1-SMAD1/5, positively and negatively regulate Robo4 expression, respectively. An ALK1 inhibitor was found to increase Robo4 expression in mouse lungs, suppress vascular permeability, prevent extravasation of melanoma cells, and decrease mortality in LPS-treated mice. The inhibitor suppressed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced endothelial barrier disruption and decreased mortality in mice infected with SARS-CoV-2. These results indicate that enhancing Robo4 expression is an efficient strategy to suppress vascular permeability and mortality in severe infectious diseases, including COVID-19, and that small molecules that upregulate Robo4 can be potential therapeutic agents against these diseases.
Assuntos
COVID-19 , Endotoxemia , Animais , Camundongos , Receptores de Superfície Celular/metabolismo , Permeabilidade Capilar , Células Endoteliais/metabolismo , Transdução de Sinais , Regulação para Cima , Endotoxemia/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , COVID-19/metabolismo , SARS-CoV-2/metabolismoRESUMO
PURPOSE: Robotic-assisted thoracoscopic surgery (RATS) is a relatively new approach to lung cancer surgery. To promote the development of RATS procedures, we investigated the factors related to short-term postoperative outcomes. METHODS: We analyzed the records of patients who underwent RATS lobectomy for primary lung cancer at our institution between June, 2018 and January, 2023. The primary outcome was operative time, and the estimated value of surgery-related factors was calculated by linear regression analysis. The secondary outcome was surgical morbidity and the risk was assessed by logistic regression analysis. RESULTS: The study cohort comprised 238 patients. Left upper lobectomy had the longest mean operative time, followed by right upper lobectomy. Postoperative complications occurred in 13.0% of the patients. Multivariate analysis revealed that upper lobectomy, the number of staples used for interlobular fissures, and the number of cases experienced by the surgeon were significantly associated with a longer operative time. The only significant risk factor for postoperative complications was heavy smoking. CONCLUSION: Patients with well-lobulated middle or lower lobe lung cancer who are not heavy smokers are recommended for the introductory period of RATS lobectomy. Improving the procedures for upper lobectomy and dividing incomplete interlobular fissures will promote the further development of RATS.
Assuntos
Neoplasias Pulmonares , Duração da Cirurgia , Pneumonectomia , Complicações Pós-Operatórias , Procedimentos Cirúrgicos Robóticos , Neoplasias Pulmonares/cirurgia , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Masculino , Pneumonectomia/métodos , Feminino , Idoso , Fatores de Risco , Resultado do Tratamento , Fatores de Tempo , Pessoa de Meia-Idade , Fumar/efeitos adversos , Fumar/epidemiologia , Toracoscopia/métodos , Cirurgia Torácica Vídeoassistida/métodos , Idoso de 80 Anos ou maisRESUMO
PURPOSE: To evaluate the safety and efficacy of new staple-line reinforcement (SLR) in pulmonary resection through a prospective study and to compare the results of this study with historical control data in an exploratory study. METHODS: The subjects of this study were 48 patients who underwent thoracoscopic lobectomy. The primary endpoint was air leakage from the staple line. The secondary endpoints were the location of air leakage, duration of air leakage, and postoperative pulmonary complications. RESULTS: The incidence of intraoperative air leakage from the staple line was 6.3%. Three patients had prolonged air leakage as a postoperative pulmonary complication. No malfunction was found in patients who underwent SLR with the stapling device. When compared with the historical group, the SLR group had a significantly lower incidence of air leakage from the staple line (6.3% vs. 28.5%, P < 0.001) and significantly shorter indwelling chest drainage time (P = 0.049) and length of hospital stay (P < 0.001). CONCLUSIONS: The use of SLR in pulmonary resection was safe and effective. When compared with conventional products, SLR could control intraoperative air leakage from the staple line and shorten time needed for indwelling chest drainage and the length of hospital stay.
Assuntos
Tempo de Internação , Pneumonectomia , Complicações Pós-Operatórias , Grampeamento Cirúrgico , Humanos , Pneumonectomia/métodos , Estudos Prospectivos , Feminino , Masculino , Grampeamento Cirúrgico/métodos , Idoso , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Toracoscopia/métodos , Complicações Intraoperatórias/prevenção & controle , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Adulto , Incidência , Segurança , Fatores de TempoRESUMO
Knowledge of the histologic type and primary origin of pulmonary tumors is essential when preparing a surgical strategy. Intraoperative diagnosis of hematoxylin and eosin (H&E)-stained frozen sections is the gold standard, but reliable pathology requires time-consuming immunohistochemistry (IHC) to distinguish among histological types/organ origins and to analyze molecular status. The aim of this study was to evaluate the clinical reliability of a new rapid-IHC technique for intraoperative diagnosis of pulmonary tumors. In total, 169 patients with undiagnosed pulmonary tumors were enrolled in a multicenter prospective observational study. At three institutes, pulmonary tumor samples were collected through core needle biopsy and/or surgery to determine surgical strategies. Using a new device for rapid IHC, we applied a high-voltage, low-frequency alternating current (AC) field, which mixes the available antibody as the voltage is switched on/off. Rapid IHC can provide tumor histologic type/origin diagnoses within 20 min, as opposed to the 3-6 h required for conventional IHC. No false diagnoses of malignancy were rendered in any of the cases when using simple H&E staining. With H&E staining alone, the overall definitive diagnosis rate, the rate of defined tumor origin, and the rate of determined histological type were 76.92%, 85.80%, and 90.53%, respectively. When rapid IHC was added, those rates were significantly improved to 88.76%, 94.67%, and 91.72%, respectively. By providing prompt and accurate intraoperative histological/molecular analysis, rapid IHC driven by AC mixing could serve as an effective clinical tool guiding the surgical strategy for undiagnosed pulmonary tumors.
Assuntos
Neoplasias Pulmonares , Humanos , Imuno-Histoquímica , Reprodutibilidade dos Testes , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Anticorpos , Pulmão/patologiaRESUMO
Bivalent H3K4me3 and H3K27me3 chromatin domains in embryonic stem cells keep active developmental regulatory genes expressed at very low levels and poised for activation. Here, we show an alternative and previously unknown bivalent modified histone signature in lineage-committed mesenchymal stem cells and preadipocytes that pairs H3K4me3 with H3K9me3 to maintain adipogenic master regulatory genes (Cebpa and Pparg) expressed at low levels yet poised for activation when differentiation is required. We show lineage-specific gene-body DNA methylation recruits H3K9 methyltransferase SETDB1, which methylates H3K9 immediately downstream of transcription start sites marked with H3K4me3 to establish the bivalent domain. At the Cebpa locus, this prevents transcription factor C/EBPß binding, histone acetylation, and further H3K4me3 deposition and is associated with pausing of RNA polymerase II, which limits Cebpa gene expression and adipogenesis.
Assuntos
Adipócitos/citologia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Metilação de DNA , Histonas/genética , PPAR gama/metabolismo , Células 3T3 , Adipócitos/fisiologia , Animais , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Cromatina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Estrutura Terciária de ProteínaRESUMO
BACKGROUND: Syphilis is a chronic disease that progresses in the primary, secondary, latent, and tertiary stages. Pulmonary manifestations of syphilis are rare, and their histological features have not been well-described. CASE PRESENTATION: A 78-year-old man was referred to our hospital because of a solitary nodular shadow in the right middle lung field on a chest radiograph. Five years prior, a rash appeared on both legs. He was tested for syphilis at a public health center, and the non-treponemal test result was negative. When he was approximately 35 years old, he had unspecified sexual intercourse. Chest computed tomography showed a 13-mm nodule with a cavity in S6 of the right lower lobe of the lung. Robot-assisted resection of the right lower lobe was performed because of suspected localized right lower lobe lung cancer. A cicatricial variant of organizing pneumonia (CiOP) was observed, and immunohistochemistry identified Treponema pallidum inside the macrophages in the nodule cavity. The rapid plasma regain (RPR) value was negative, and the Treponema pallidum hemagglutination assay was positive. The patient was diagnosed as having secondary syphilis with pulmonary involvement. Insidious progression of secondary syphilis may result in CiOP and a negative RPR test result. CONCLUSIONS: We report the first case of pulmonary syphilis with a histological pattern of CiOP. It may be asymptomatic and difficult to diagnose because the RPR test may be negative for a long period of time. When either non-treponemal or treponemal test results are positive, the possibility of pulmonary syphilis should be considered along with appropriate medical treatment.
Assuntos
Pneumonia em Organização , Pneumonia , Sífilis , Masculino , Humanos , Idoso , Adulto , Sífilis/complicações , Sífilis/diagnóstico , Treponema pallidum , Pulmão/diagnóstico por imagemRESUMO
PURPOSE: Many effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been developed, but a weaker response in individuals undergoing anticancer treatment has been reported. This study evaluates the immunogenic status and safety of SARS-CoV-2 vaccines for patients with non-small-cell lung cancer (NSCLC), receiving tegafur-uracil (UFT) as postoperative adjuvant chemotherapy. METHODS: The subjects of this prospective study were 40 patients who underwent surgery for NSCLC and received SARS-CoV-2 vaccines postoperatively. We compared the antibody titers of SARS-CoV-2 vaccines and the adverse events between patients who received adjuvant UFT and patients who did not. RESULTS: The mean anti-S1 IgG titers were not significantly different between the UFT and without-UFT groups (mean optimal density, 0.194 vs. 0.205; P = 0.76). Multivariate analysis identified the period after the second vaccination as an independent predictor of anti-S1 IgG titer (P = 0.049), but not the UFT status (with or without-UFT treatment; P = 0.47). The prevalence of adverse events did not differ significantly between the groups, and no severe adverse events occurred. CONCLUSIONS: The efficacy and safety of the SARS-CoV-2 vaccines for NSCLC patients who received postoperative adjuvant UFT chemotherapy were comparable to those for NSCLC patients who did not receive postoperative adjuvant UFT chemotherapy. CLINICAL TRIAL REGISTRATION: This study was registered with the University Hospital Medical Information Network (UMIN) in Japan (UMIN000047380).
Assuntos
COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Quimioterapia Adjuvante , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Imunoglobulina G/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/cirurgia , Estadiamento de Neoplasias , Estudos Prospectivos , SARS-CoV-2 , Tegafur , UracilaRESUMO
The undifferentiated state of muscle stem (satellite) cells (MuSCs) is maintained by the canonical Notch pathway. Although three bHLH transcriptional factors, Hey1, HeyL and Hes1, are considered to be potential effectors of the Notch pathway exerting anti-myogenic effects, neither HeyL nor Hes1 inhibits myogenic differentiation of myogenic cell lines. Furthermore, whether these factors work redundantly or cooperatively is unknown. Here, we showed cell-autonomous functions of Hey1 and HeyL in MuSCs using conditional and genetic null mice. Analysis of cultured MuSCs revealed anti-myogenic activity of both HeyL and Hes1. We found that HeyL forms heterodimeric complexes with Hes1 in living cells. Moreover, our ChIP-seq experiments demonstrated that, compared with HeyL alone, the HeyL-Hes1 heterodimer binds with high affinity to specific sites in the chromatin, including the binding sites of Hey1. Finally, analyses of myogenin promoter activity showed that HeyL and Hes1 act synergistically to suppress myogenic differentiation. Collectively, these results suggest that HeyL and Hey1 function redundantly in MuSCs, and that HeyL requires Hes1 for effective DNA binding and biological activity.
Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação da Expressão Gênica , Células Satélites de Músculo Esquelético/citologia , Fatores de Transcrição HES-1/metabolismo , Alelos , Animais , Sítios de Ligação , Separação Celular , Cromatina/química , DNA/química , Citometria de Fluxo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Regiões Promotoras Genéticas , Ligação Proteica , Multimerização Proteica , Estrutura Secundária de Proteína , Receptores Notch/metabolismo , Transdução de SinaisRESUMO
The lysine methyltransferase SETDB1, an enzyme responsible for methylation of histone H3 at lysine 9, plays a key role in H3K9 tri-methylation-dependent silencing of endogenous retroviruses and developmental genes. Recent studies have shown that ubiquitination of human SETDB1 complements its catalytic activity and the silencing of endogenous retroviruses in human embryonic stem cells. However, it is not known whether SETDB1 ubiquitination is essential for its other major role in epigenetic silencing of developmental gene programs. We previously showed that SETDB1 contributes to the formation of H3K4/H3K9me3 bivalent chromatin domains that keep adipogenic Cebpa and Pparg genes in a poised state for activation and restricts the differentiation potential of pre-adipocytes. Here, we show that ubiquitin-resistant K885A mutant of SETDB1 represses adipogenic genes and inhibits pre-adipocyte differentiation similar to wild-type SETDB1. We show this was due to a compensation mechanism for H3K9me3 chromatin modifications on the Cebpa locus by other H3K9 methyltransferases Suv39H1 and Suv39H2. In contrast, the K885A mutant did not repress other SETDB1 target genes such as Tril and Gas6 suggesting SETDB1 represses its target genes by two mechanisms; one that requires its ubiquitination and another that still requires SETDB1 but not its enzyme activity.
Assuntos
Adipogenia , Epigênese Genética , Histona-Lisina N-Metiltransferase/metabolismo , Ubiquitinação , Células 3T3-L1 , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Células HEK293 , Código das Histonas , Histona-Lisina N-Metiltransferase/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Mutação de Sentido IncorretoRESUMO
OBJECTIVE: The human epidermis is formed by the proliferation and differentiation of keratinocytes adjacent to the basement membrane. The outermost layer, the stratum corneum, is equipped with a barrier function that prevents water evaporation, and intercellular lipids play an important role in this barrier function. When the barrier is functioning normally, evaporation is prevented; however, when barrier function is impaired, moisture evaporates, resulting in dry and rough skin. Therefore, maintenance of normal barrier function is critical for maintaining normal skin function. Peroxisome proliferator-activated receptor α (PPARα) is mainly not only involved in lipid metabolism in the liver but is also expressed in the epidermis and is involved in inducing keratinocyte differentiation, promoting lipid production, maintaining barrier function and suppressing skin inflammation. Hence, compounds that activate PPARα are expected to control skin function. Therefore, we identified PPARα activators from among extracts of natural resources that have been approved for use in humans and analysed the effects of these extracts on skin function. METHODS: First, extracts of 474 natural resources were screened using a PPARα activator screening cell line independently constructed in our laboratory. Next, reporter assays were performed using the Gal4-chimera system to evaluate whether these extracts act as ligands for PPARα. We then analysed their effect on primary normal human epidermal keratinocyte cells by using real-time RT-PCR. Finally, we evaluated PPARα activation effect by the combination of these extracts. RESULTS: We identified 36 extracts having the effect of activating PPARα. In particular, #419, a Typha angustifolia spike extract, showed concentration-dependent transcriptional activation through PPARα-LBD and was considered to be likely to contain a compound that is a ligand of PPARα. #419 increased the expression of PPARα target genes and genes related to skin function in primary cultured human epidermal keratinocytes. Finally, the use of #419 in combination with nine extracts increased PPAR activity more than twice as much as #419 alone treatment. CONCLUSIONS: These results showed that the reporter cell line could be useful for discovering extracts of natural resources and that the identified Typha angustifolia spike extract could be used in cosmetics that activate PPARα, which expected to improve skin function.
OBJECTIF: L'épiderme humain se forme grâce à la prolifération et à la différenciation des kératinocytes adjacents à la membrane basale. La couche externe, dite « couche cornée ¼, possède une fonction barrière qui empêche l'évaporation de l'eau, dans laquelle les lipides intercellulaires jouent un rôle important. Lorsque la barrière fonctionne normalement, l'évaporation est évitée ; mais lorsqu'elle est altérée, l'évaporation a lieu et la peau, privée d'hydratation, devient sèche et rêche. Par conséquent, il est capital de maintenir cette fonction barrière normale pour que la peau conserve son fonctionnement normal. Le récepteur alpha activé par proliférateurs de peroxysomes (PPARα) intervient surtout non seulement dans le métabolisme lipidique du foie, mais également dans l'épiderme ; il joue en effet un rôle dans l'induction de la différenciation des kératinocytes, la promotion de la production lipidique, le maintien de la fonction barrière et la suppression de l'inflammation de l'épiderme. Par conséquent, les activateurs du PPAR-α devraient être déterminants pour une bonne fonction cutanée. Nous avons donc identifié des activateurs du PPAR-α parmi des extraits de ressources naturelles dont l'utilisation chez l'homme est approuvée, et nous avons analysé les effets de ces extraits sur la fonction cutanée. MÉTHODES: Tout d'abord, des extraits de 474 ressources naturelles ont été sélectionnés à l'aide d'une lignée cellulaire de détection des activateurs du PPAR-α, construite indépendamment dans notre laboratoire. Ensuite, des tests de gènes rapporteurs ont été effectués à l'aide du système Gal4-chimera pour voir si ces extraits jouaient le rôle de ligands pour le PPAR-α. Nous avons ensuite analysé leur effet sur les cellules kératinocytaires épidermiques humaines normales primaires par RT-PCR en temps réel. Enfin, nous avons évalué l'effet d'activation du PPAR-α par l'association de ces extraits. RÉSULTATS: Nous avons identifié 36 extraits ayant pour effet d'activer le PPAR-α. En particulier, le n° 419, un extrait d'épi de Typha angustifolia, a montré une activation transcriptionnelle dépendante de la concentration par le PPAR-α-LBD et a été considéré comme susceptible de contenir un composé qui est un ligand du PPAR-α. Le n° 419 a augmenté l'expression des gènes cibles du PPAR-α et des gènes liés au fonctionnement de la peau dans les kératinocytes épidermiques humains primaires mis en culture. Enfin, l'utilisation du n° 419 en association avec neuf extraits a augmenté de plus du double l'activité du PPAR par rapport au traitement par le n° 419 seul. CONCLUSIONS: Ces résultats ont montré que la lignée cellulaire rapporteuse pourrait être utile pour découvrir des extraits de ressources naturelles et que l'extrait d'épi de Typha angustifolia identifié pourrait être utilisé dans des cosmétiques qui activent le PPAR-α, ce qui devrait améliorer la fonction cutanée.
Assuntos
Cosméticos , PPAR alfa , Cosméticos/metabolismo , Cosméticos/farmacologia , Humanos , Queratinócitos , Ligantes , Extratos Vegetais , Pele/metabolismoRESUMO
Roundabout guidance receptor 4 (Robo4) is an endothelial cell-specific receptor that stabilizes the vasculature in pathological angiogenesis. Although Robo4 has been shown to suppress vascular hyperpermeability induced by vascular endothelial growth factor (VEGF) in angiogenesis, the role of Robo4 in inflammation is poorly understood. In this study, we investigated the role of Robo4 in vascular hyperpermeability during inflammation. Endotoxemia models using Robo4-/- mice showed increased mortality and vascular leakage. In endothelial cells, Robo4 suppressed tumor necrosis factor α (TNFα)-induced hyperpermeability by stabilizing VE-cadherin at cell junctions, and deletion assays revealed that the C-terminus of Robo4 was involved in this suppression. Through binding and localization assays, we demonstrated that in endothelial cells, Robo4 binds to TNF receptor-associated factor 7 (TRAF7) through interaction with the C-terminus of Robo4. Gain- and loss-of-function studies of TRAF7 with or without Robo4 expression showed that TRAF7 is required for Robo4-mediated suppression of hyperpermeability. Taken together, our results demonstrate that the Robo4-TRAF7 complex is a novel negative regulator of inflammatory hyperpermeability. We propose this complex as a potential future target for protection against inflammatory diseases.
Assuntos
Permeabilidade da Membrana Celular , Endotélio Vascular/patologia , Endotoxemia/complicações , Inflamação/patologia , Neovascularização Patológica/patologia , Receptores de Superfície Celular/fisiologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Sequência de Aminoácidos , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Modelos Animais de Doenças , Endotélio Vascular/metabolismo , Endotoxemia/induzido quimicamente , Inflamação/etiologia , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neovascularização Patológica/etiologia , Neovascularização Patológica/metabolismo , Transdução de Sinais , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genéticaRESUMO
Roundabout4 (Robo4) is an endothelial cell-specific protein that stabilizes the vasculature in pathological angiogenesis and inflammation. We previously determined a 3-kb Robo4 promoter and demonstrated the importance of the upstream region for nuclear factor-kappaB (NF-κB)-mediated promoter activation induced by tumor necrosis factor α (TNFα). This region contains unique genomic features, including promoter region-specific DNA hypermethylation and chromatin condensation; however, the function of the region remains poorly understood. In this study, we analyzed the DNA sequences of the region and identified a motif for polycomb repressive complex 2 (PRC2). Chromatin immunoprecipitation assay indicates the binding of the PRC2 component, SUZ12, to the motif. A mutation in the motif decreased DNA methylation in embryonic stem cells and increased Robo4 promoter activity in endothelial cells. An inhibitor for the PRC2 component, EZH2, induced the promoter activity and expression of Robo4 in endothelial cells treated with or without TNFα. Taken together, these results indicate that the PRC2 components maintain DNA hypermethylation and suppress Robo4 expression via the PRC2 binding motif in the upstream promoter.
Assuntos
Metilação de DNA , Células Endoteliais da Veia Umbilical Humana/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas , Receptores de Superfície Celular/genética , Animais , Células Cultivadas , Células-Tronco Embrionárias/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/farmacologia , Regulação da Expressão Gênica , Humanos , Camundongos , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Peroxisome proliferator-activated receptor α (PPARα) is a ligand-activated transcription factor that belongs to the superfamily of nuclear hormone receptors. PPARα is mainly expressed in the liver, where it activates fatty acid oxidation and lipoprotein metabolism and improves plasma lipid profiles. Therefore, PPARα activators are often used to treat patients with dyslipidemia. To discover additional PPARα activators as potential compounds for use in hypolipidemic drugs, here we established human hepatoblastoma cell lines with luciferase reporter expression from the promoters containing peroxisome proliferator-responsive elements (PPREs) and tetracycline-regulated expression of full-length human PPARα to quantify the effects of chemical ligands on PPARα activity. Using the established cell-based PPARα-activator screening system to screen a library of >12,000 chemical compounds, we identified several hit compounds with basic chemical skeletons different from those of known PPARα agonists. One of the hit compounds, a 1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid derivative we termed compound 3, selectively up-regulated PPARα transcriptional activity, leading to PPARα target gene expression both in vitro and in vivo Of note, the half-maximal effective concentrations of the hit compounds were lower than that of the known PPARα ligand fenofibrate. Finally, fenofibrate or compound 3 treatment of high fructose-fed rats having elevated plasma triglyceride levels for 14 days indicated that compound 3 reduces plasma triglyceride levels with similar efficiency as fenofibrate. These observations raise the possibility that 1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid derivatives might be effective drug candidates for selective targeting of PPARα to manage dyslipidemia.
Assuntos
Regulação da Expressão Gênica , PPAR alfa/genética , PPAR alfa/metabolismo , Animais , Avaliação Pré-Clínica de Medicamentos , Frutose/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter/genética , Humanos , Hipolipemiantes/farmacologia , Ligantes , RatosRESUMO
Lipin-1 has multiple functions that regulate lipid and energy metabolism according to its subcellular localization. The subcellular localization of Lipin-1 is determined by kinase-dependent phosphorylation; however, the phosphatase that dephosphorylates and inactivates Lipin-1 has remained elusive. Using an immunoprecipitation and LC-MS/MS approach we have identified phosphoglycerate mutase family member 5 (PGAM5), a serine/threonine specific protein phosphatase, as a regulator of Lipin-1 activity. Treatment of human hepatocellular carcinoma cells with carbonyl cyanide m-chlorophenyl hydrazone (CCCP), which activates endogenous PGAM5, promoted dephosphorylation and nuclear accumulation of Lipin-1. Our findings further elucidate the molecular mechanisms that regulate Lipin-1.
Assuntos
Proteínas Mitocondriais/metabolismo , Fosfatidato Fosfatase/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Transporte Ativo do Núcleo Celular , Carcinoma Hepatocelular/metabolismo , Humanos , Metabolismo dos Lipídeos , Neoplasias Hepáticas/metabolismo , Fosforilação , Ligação Proteica , Células Tumorais CultivadasRESUMO
Claudin (CLDN) proteins, a tetra-transmembrane family containing over 20 members, have been identified as key structural and functional components of intercellular seals, tight junctions (TJs). CLDNs are involved in the barrier and fence functions of TJs. Loosening the TJ barrier is one strategy for increasing drug absorption and delivery to the brain. Due to aberrant CLDN expression, the TJ fence function is frequently dysregulated in carcinogenesis. In addition, CLDN-1 is a co-receptor for the hepatitis C virus. Together these characteristics indicate CLDNs as promising targets for drug development, and CLDN binders are potential candidates for delivering drugs, treating cancer, and preventing viral infection. Before 2008, a receptor-binding fragment of Clostridium perfringens enterotoxin was the only CLDN binder available. Since then, several challenges regarding the generation of monoclonal antibodies against CLDNs have been surmounted, leading to breakthroughs in CLDN-targeted drug development. Here, we provide an overview of the recent progress in technology using created CLDN binders-anti-CLDN monoclonal antibodies.
Assuntos
Autoanticorpos/metabolismo , Claudinas/antagonistas & inibidores , Claudinas/metabolismo , Desenvolvimento de Medicamentos/tendências , Preparações Farmacêuticas/metabolismo , Sequência de Aminoácidos , Animais , Autoanticorpos/genética , Claudinas/genética , HumanosRESUMO
Malignant pleural mesothelioma (MPM) is a highly aggressive tumor with poor prognosis and closely related to exposure to asbestos. MPM is a heterogeneous tumor with three main histological subtypes, epithelioid, sarcomatoid, and biphasic types, among which sarcomatoid type shows the poorest prognosis. The Ror-family of receptor tyrosine kinases, Ror1 and Ror2, is expressed in various types of tumor cells at higher levels and affects their aggressiveness. However, it is currently unknown whether they are expressed in and involved in aggressiveness of MPM. Here, we show that Ror1 and Ror2 are expressed in clinical specimens and cell lines of MPM with different histological features. Studies using MPM cell lines indicate that expression of Ror2 is associated tightly with high invasiveness of MPM cells, whereas Ror1 can contribute to their invasion in the absence of Ror2. However, both Ror1 and Ror2 promote proliferation of MPM cells. We also show that promoted invasion and proliferation of MPM cells by Ror signaling can be mediated by the Rho-family of small GTPases, Rac1, and Cdc42. These findings elucidate the critical role of Ror signaling in promoting invasion and proliferation of MPM cells.
Assuntos
Neoplasias Pulmonares/metabolismo , Mesotelioma/metabolismo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Pulmonares/genética , Mesotelioma/genética , Mesotelioma Maligno , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/fisiologia , Transdução de SinaisRESUMO
We previously reported that 1H-pyrazolo-[3,4-b]pyridine-4-carboxylic acid derivative 6 is an agonist of human peroxisome proliferator-activated receptor alpha (hPPARα). Here, we prepared a series of 1H-pyrazolo-[3,4-b]pyridine-4-carboxylic acid derivatives in order to examine the structure-activity relationships (SAR). SAR studies clearly indicated that the steric bulkiness of the substituent on 1H-pyrazolo-[3,4-b]pyridine ring, the position of the distal hydrophobic tail part, and the distance between the distal hydrophobic tail part and the acidic head part are critical for hPPARα agonistic activity. These SAR results are somewhat different from those reported for fibrate-class hPPARα agonists. A representative compound (10f) was as effective as fenofibrate in reducing the elevated plasma triglyceride levels in a high-fructose-fed rat model.
Assuntos
PPAR alfa/agonistas , Piridinas/química , Humanos , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor superfamily and include three subtypes (PPARα, PPARδ, and PPARγ). They regulate gene expression in a ligand-dependent manner. PPARα plays an important role in lipid metabolism. PPARγ is involved in glucose metabolism and is a potential therapeutic target in Type 2 diabetes. PPARδ ligands are candidates for the treatment of metabolic disorders. Thus, the detection of PPAR ligands may facilitate the treatment of various diseases. In this study, to identify PPAR ligands, we engineered reporter cell lines that can be used to quantify PPARγ and PPARδ activity. We evaluated several known ligands using these reporter cell lines and confirmed that they are useful for PPAR ligand detection. Furthermore, we evaluated extracts of approximately 200 natural resources and found various extracts that enhance reporter gene activity. Finally, we identified a main alkaloid of the Evodia fruit, evodiamine, as a PPARγ activator using this screening tool. These results suggest that the established reporter cell lines may serve as a useful cell-based screening tool for finding PPAR ligands to ameliorate metabolic syndromes.
Assuntos
Síndrome Metabólica/prevenção & controle , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Linhagem Celular , Ensaios de Triagem em Larga Escala , Humanos , Ligantes , Síndrome Metabólica/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/genética , Extratos Vegetais/farmacologiaRESUMO
In advanced cancer patients, malignant cells invade and disseminate within normal cells and develop resistance to therapy with additional genetic mutations, which makes radical cure very difficult. Precision medicine against advanced cancer is hampered by the lack of systems aimed at multiple target molecules within multiple loci. Here, we report the development of a versatile diagnostic and therapeutic system for advanced cancer, named the Cupid and Psyche system. Based on the strong non-covalent interaction of streptavidin and biotin, a low immunogenic mutated streptavidin, Cupid, and a modified artificial biotin, Psyche, have been designed. Cupid can be fused with various single-chain variable fragment antibodies and forms tetramer to recognize cancer cells precisely. Psyche can be conjugated to a wide range of diagnostic and therapeutic agents against malignant cells. The Cupid and Psyche system can be used in pre-targeting therapy as well as photo-immunotherapy effectively in animal models supporting the concept of a system for precision medicine for multiple targets within multiple loci.
Assuntos
Antineoplásicos/química , Biotina/química , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Estreptavidina/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Humanos , Imunoterapia , Medicina de Precisão , Anticorpos de Cadeia Única/químicaRESUMO
A 39-year-old man was admitted to our hospital with back pain and numbness of the left leg. Computed tomography (CT) showed a giant bulla and tumor in the right lung, mediastinal shift to the left side and lesions suggestive of metastatic sacral tumor. Three days later, the patient visited the emergency room with dyspnea and tachycardia. Chest CT showed the progression of mediastinal shift due to the rapid expansion of the giant bulla, and an emergency surgery was performed. After induction of anesthesia, sudden respiratory and circulatory failure occurred. Considering further expansion of the giant bulla by positive pressure ventilation, veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) was applied. After establishing ECMO, the condition of the patient became stable and the giant bulla could be resected successfully.