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Perilla meal hydrolysates (PMHs) were prepared by proteases; volatile profiles from heated mixtures of PMH and coconut oil (CO) were evaluated for their application as odor providers. Amino acids composition and degree of hydrolysis, and antioxidant activity in O/W emulsion of PMHs were assessed. PMHs were heated with different concentration of CO or with CO, xylose, and cysteine, which were non-Maillard and Maillard system, respectively. Among PMHs, double enzyme treatment using Alcalase and Flavourzyme showed higher degree of hydrolysis and antioxidant activity compared to PMHs from one type of enzymes. The presence of CO significantly increased oxygen, sulfur, and nitrogen-containing volatiles from PMHs in non-Maillard system. In case of Maillard system, PMHs with 10 % (w/w) CO contributed the formation of oxygen and nitrogen-containing volatiles such as furan and 2-methylpyrazine. PMHs might serve as an odor generator in the presence of edible oils like CO.
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Reação de Maillard , Perilla , Antioxidantes , Óleo de Coco , Nitrogênio , Oxigênio , Cadáver , Hidrolisados de ProteínaRESUMO
PURPOSE: Total kidney volume (TKV) measurement is crucial for selecting treatment candidates in autosomal dominant polycystic kidney disease (ADPKD). We developed and investigated the performance of fully-automated 3D-volumetry model and applied it to software as a service (SaaS) for clinical support on tolvaptan prescription in ADPKD patients. MATERIALS AND METHODS: Computed tomography scans of ADPKD patients taken between January 2000 and June 2022 were acquired from seven institutions. The quality of the images was manually reviewed in advance. The acquired dataset was split into training, validation, and test datasets at a ratio of 8.5:1:0.5. Convolutional, neural network-based automatic segmentation model was trained to obtain 3D segment mask for TKV measurement. The algorithm consisted of three steps: data preprocessing, ADPKD area extraction, and post-processing. After performance validation with the Dice score, 3D-volumetry model was applied to SaaS which is based on Mayo imaging classification for ADPKD. RESULTS: A total of 753 cases with 95,117 slices were included. The differences between the ground-truth ADPKD kidney mask and the predicted ADPKD kidney mask were negligible, with intersection over union >0.95. The post-process filter successfully removed false alarms. The test-set performance was homogeneously equal and the Dice score of the model was 0.971; after post-processing, it improved to 0.979. The SaaS calculated TKV from uploaded Digital Imaging and Communications in Medicine images and classified patients according to height-adjusted TKV for age. CONCLUSIONS: Our artificial intelligence-3D volumetry model exhibited effective, feasible, and non-inferior performance compared with that of human experts and successfully predicted the rapid ADPKD progressor.
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Rim Policístico Autossômico Dominante , Humanos , Rim Policístico Autossômico Dominante/diagnóstico por imagem , Rim Policístico Autossômico Dominante/tratamento farmacológico , Tolvaptan/uso terapêutico , Inteligência Artificial , Estudos de Viabilidade , Progressão da Doença , Taxa de Filtração GlomerularRESUMO
Anterior cruciate ligament (ACL) reconstruction is often performed using a tendon graft. However, the predominant synthesis of fibrotic scar tissue (type III collagen) occurs during the healing process of the tendon graft, resulting in a significantly lower mechanical strength than that of normal ACL tissue. In this study, ACL-derived cells were reseeded to the tendon graft, and scaffold-induced compression was applied to test whether the compressive force results in superior cell survival and integration. Given nanofiber polycaprolactone (PCL) scaffold-induced compression, ACL-derived cells reseeded to a tendon graft demonstrated superior cell survival and integration and resulted in higher gene expression levels of type I collagen compared to non-compressed cell-allograft composites in vitro. Translocation of Yes-associated protein (YAP) into the nucleus was correlated with higher expression of type I collagen in the compression group. These data support the hypothesis of a potential role of mechanotransduction in the ligamentization process.
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AIMS: To test the hypothesis that reseeded anterior cruciate ligament (ACL)-derived cells have a better ability to survive and integrate into tendon extracellular matrix (ECM) and accelerate the ligamentization process, compared to adipose-derived mesenchymal stem cells (ADMSCs). METHODS: Acellularized tibialis allograft tendons were used. Tendons were randomly reseeded with ACL-derived cells or ADMSCs. ACL-derived cells were harvested and isolated from remnants of ruptured ACLs during reconstruction surgery and cultured at passage three. Cell suspensions (200 µl) containing 2 × 106 ACL-derived cells or ADMSCs were prepared for the purpose of reseeding. At days 1, 3, and 7 post-reseeding, graft composites were assessed for repopulation with histological and immunohistochemical analysis. Matrix protein contents and gene expression levels were analyzed. RESULTS: In the graft reseeded with ACL-derived cells, a large number of elongated cells that integrated into the matrix were evident at day 3 and day 7. However, in the graft reseeded with ADMSCs, only a small number of elongated cells were found integrated into the matrix. Immunofluorescence for Ki-67 and type I collagen confirmed the pronounced production of type I collagen by Ki-67-positive ACL-derived cells integrated into the ECM. A messenger RNA (mRNA) expression assay demonstrated significantly higher gene expression levels of types I (p = 0.013) and III (p = 0.050) collagen in the composites reseeded with ACL-derived cells than ADMSCs. CONCLUSION: ACL-derived cells, when reseeded to acellularized tendon graft, demonstrated earlier better survival and integration in the tendon ECM and resulted in higher gene expression levels of collagen, which may be essential to the normal ligamentization process compared to ADMSCs.Cite this article: Bone Joint Res 2022;11(11):777-786.
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The matrix protein 2 of influenza A virus (IFAV) has a relatively conserved ectodomain (M2e) composed of 23 amino acids, and M2e-based vaccines have been suggested to induce broad protective immunity in mice. In this study, we investigated whether N-terminal sequence of M2e (nM2e)-based vaccines with more conserved nM2e could induce influenza viral neutralizing activity. We constructed linear peptide vaccines with an nM2e sequence for PR8 virus (nM2Pr) connected to a probable 17-mer IFAV-derived helper T-cell epitope (ThE: T1, T2, or T3) at its N- or C-terminus. The peptide vaccines induced significant production of nM2e Abs regardless of either type or location of the ThE-epitope in BALB/c mice, while only T3 was effective in C57BL/6 mice. The Abs against nM2Pr-T3 elicited broader binding affinities to the nM2e peptides derived from various IFAVs than those against T3-nM2Pr. In addition, the nM2e-based vaccines efficiently protected the immunized mice from the lethal challenge of PR8 virus. These results suggest that the more conserved nM2e without cysteine will be useful for development of universal peptide vaccines than M2e.
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Previously a scalable and extrusion-free method has been developed for efficient liposomal encapsulation of DNA by twice stepwise mixing of lipids in ethanol and DNA solution using T-shape mixing chamber. In this study, we prepared nanoliposomes encapsulating siRNA by simply discontinuous mixing of lipids in ethanol/ether/water mixture and acidic siRNA solution without use of special equipment. The simple mixing siRNA/liposomal particles (siRNA/SMLs) prepared using ethanol/ether/water (3:1:1) mixture showed 120.4⯱â¯20.2â¯nm particle size, 0.174⯱â¯0.033 polydispersity and 86.5⯱â¯2.76% siRNA encapsulation rate. In addition, the SMLs almost completely protected the encapsulated siRNA from RNase A digestion. Coupling of anti-human epidermal growth factor receptor (EGFR) Fab' to siRNA/SMLs enhanced EGFR-specific cell penetration of SMLs and induced siRNA dependent gene silencing. Unexpectedly, the Cy5.5-labeled Fab' showed almost no in vivo targeting to the xenografted A549 tumors in SCID-NOD mice. However, multiple injection of the unmodified siRNA/SMLs accumulated in the tumors and induced siRNA-dependent in vivo gene silencing. These results demonstrate that the siRNA/SMLs can be used as a siRNA delivery tool for gene therapy.
Assuntos
Sistemas de Liberação de Medicamentos/métodos , Lipossomos , Nanoestruturas , RNA Interferente Pequeno/administração & dosagem , Animais , Composição de Medicamentos , Receptores ErbB/antagonistas & inibidores , Humanos , Fragmentos Fab das Imunoglobulinas , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Terapia de Alvo Molecular , Células NIH 3T3 , Proteínas de Neoplasias/antagonistas & inibidores , Tamanho da Partícula , Interferência de RNA , RNA Interferente Pequeno/farmacocinética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Hypoxia-inducible factor 1 (HIF-1) is a key player in cellular response to hypoxia. The stability and transcriptional activity of this protein are oxygen-dependently regulated by the prolyl hydroxylases PHD1-3 and the asparaginyl hydroxylase FIH. Recently, ferritin heavy chain (FTH1) has been characterized to reinforce the HIF-1 signaling pathway in an indirect way through the inhibition of PHD activity by depleting the free iron pool in the cytoplasm. In the present study, we addressed the role of FTH1 in the FIH control of HIF-1 activity. Unexpectedly, immunoprecipitation analyses revealed that FTH1 directly interacted with FIH. In an in vitro hydroxylation assay, FTH1 was found to facilitate the FIH-mediated Asn803 hydroxylation in HIF-1α. As expected, FTH1 prevented the recruitment of p300 to HIF-1α through the Asn803 hydroxylation. In luciferase reporter analyses, FTH1 was found to repress the transcriptional activity of HIF-1α in HCT116â¯cells under either normoxic or hypoxic conditions. Consequently, FTH1 downregulated the expression of the HIF-1 target genes, such as VEGF, CA9 and GLUT1. Our results suggest a new role of FTH1 as a co-regulator for the FIH-mediated oxygen sensing pathway. Since HIF-1α is involved in pathogenesis of diverse hypoxia-associated diseases, we propose that FTH1 be a potential target in developing new therapeutic strategies against such diseases.
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Ferritinas/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Oxigenases de Função Mista/metabolismo , Proteínas Repressoras/metabolismo , Asparagina/metabolismo , Hipóxia Celular/genética , Regulação da Expressão Gênica , Células HEK293 , Humanos , Hidroxilação , Oxirredutases , Ligação Proteica , Transcrição GênicaRESUMO
Agarose gel can be used for three dimensional (3D) cell culture because it prevents cell attachment. The dried agarose film coated on a culture plate also protected cell attachment and allowed 3D growth of cancer cells. We developed an efficient method for agarose film coating on an oxygen-plasma treated micropost polystyrene chip prepared by an injection molding process. The agarose film was modified to maleimide or Ni-NTA groups for covalent or cleavable attachment of photoactivatable Fc-specific antibody binding proteins (PFcBPs) via their N-terminal cysteine residues or 6xHis tag, respectively. The antibodies photocrosslinked onto the PFcBP-modified chips specifically captured the target cells without nonspecific binding, and the captured cells grew 3D modes on the chips. The captured cells on the cleavable antibody-modified chips were easily recovered by treatment of commercial trypsin-EDTA solution. Under fluidic conditions using an antibody-modified micropost chip, the cells were mainly captured on the micropost walls of the chip rather than on the bottom of it. The presented method will also be applicable for immobilization of oriented antibodies on various microfluidic chips with different structures.
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Anticorpos Monoclonais/metabolismo , Separação Celular/métodos , Análise em Microsséries/instrumentação , Poliestirenos/química , Sefarose/química , Técnicas de Cultura de Tecidos/instrumentação , Células A549 , Animais , Anticorpos Monoclonais/química , Separação Celular/instrumentação , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Expressão Gênica , Humanos , Dispositivos Lab-On-A-Chip , Camundongos , Poliestirenos/metabolismo , Ligação Proteica , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Sefarose/metabolismo , TransgenesRESUMO
Fc-specific antibody binding proteins (FcBPs) with the minimal domain of protein G are widely used for immobilization of well-oriented antibodies onto solid surfaces, but the noncovalently bound antibodies to FcBPs are unstable in sera containing large amounts of antibodies. Here we report novel photoactivatable FcBPs with photomethionine (pMet) expressed in E. coli, which induce Fc-specific photo-cross-linking with antibodies upon UV irradiation. Unfortunately, pMet did not support protein expression in the native E. coli system, and therefore we also developed an engineered methionyl tRNA synthetase (MRS5m). Coexpression of MRS5m proteins successfully induced photoactivatable FcBP overexpression in methionine-auxotroph E. coli cells. The photoactivatable FcBPs could be easily immobilized on beads and slides via their N-terminal cysteine residues and 6xHis tag. The antibodies photo-cross-linked onto the photoactivatable FcBP-beads were resistant from serum-antibody mediated dissociation and efficiently captured antigens in human sera. Furthermore, photo-cross-linked antibody arrays prepared using this system allowed sensitive detection of antigens in human sera by sandwich immunoassay. The photoactivatable FcBPs will be widely applicable for well-oriented antibody immobilization on various surfaces of microfluidic chips, glass slides, and nanobeads, which are required for development of sensitive immunosensors.
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Anticorpos Monoclonais/química , Proteínas de Transporte/efeitos da radiação , Proteínas de Escherichia coli/efeitos da radiação , Fragmentos Fc das Imunoglobulinas/química , Anticorpos Monoclonais/imunologia , Antígenos/sangue , Antígenos/imunologia , Azidas/química , Azidas/efeitos da radiação , Proteínas de Transporte/química , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/efeitos da radiação , Escherichia coli/imunologia , Proteínas de Escherichia coli/química , Humanos , Imunoensaio , Fragmentos Fc das Imunoglobulinas/imunologia , Metionina/análogos & derivados , Metionina/química , Metionina/efeitos da radiação , Metionina tRNA Ligase/química , Raios UltravioletaRESUMO
This work demonstrates successful delivery of a gene to EGFR-overexpressed cancer cells by using a rationally designed branched GE11 peptide as a targeting ligand. In addition, we exploited the effect of the divalent structure of the branched GE11 peptide on the gene delivery and tumor targeting efficiency, compared to the monovalent GE11 peptide. The GE11 or branched GE11-tethered polymers were successfully synthesized. They are composed of a targeting peptide, disulfide crosslinked low molecular weight polyethylenimine and polyethylene glycol. Here, we evaluated the physicochemical properties, cytotoxicity and in vitro transfection efficiency and in vivo biodistribution of the GE11 and branched GE11 tethered polyplexes. Our results demonstrated that GE11 and bGE11-tethered gene delivery carriers showed efficient gene condensing ability, an enhanced transfection efficiency and targeting ability with low cytotoxicity. Interestingly, the branched GE11-tethered polymer showed the greater targeting ability to EGFR-overexpressed cancer cells in vivo than the GE11-tethered polymer. Therefore, this branched structure of targeting ligand has the potential for providing a novel strategy to design an efficient targeted delivery system.
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Sistemas de Liberação de Medicamentos/métodos , Peptídeos/química , Peptídeos/farmacocinética , Polietilenoglicóis/química , Polietilenoimina/química , Linhagem Celular Tumoral , Técnicas de Transferência de Genes , Terapia Genética/métodos , Humanos , Ligantes , Peptídeos/metabolismo , PolímerosRESUMO
Myoglobin is an early biomarker for acute myocardial infarction. Recently, we isolated the antibody IgG-Myo2-7ds, which exhibits unique rapid reaction kinetics toward human myoglobin antigen. Antibodies with rapid dissociation kinetics are thought to be premature IgG forms that are produced during the early stage of in vivo immunization. In the present study, we identified the epitope region of the IgG-Myo2-7ds antibody to be the C-terminal region of myoglobin, which corresponds to 144-154 aa. The Fab fragment was directly purified by papain cleavage and protein G affinity chromatography and demonstrated kinetics of an association constant of 4.02 × 10(4) M(-1) s(-1) and a dissociation constant of 2.28 × 10(-2) s(-1), which retained the unique reaction kinetics of intact IgG-Myo2-7ds antibodies. Because a rapid dissociation antibody can be utilized for antibody recycling, the results from this study would provide a platform for the development of antibody engineering in potential diagnostic areas such as a continuous monitoring system for heart disease.
Assuntos
Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Fragmentos Fab das Imunoglobulinas/metabolismo , Mioglobina/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Cromatografia de Afinidade/métodos , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Epitopos/imunologia , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Cinética , Camundongos , Dados de Sequência Molecular , Mioglobina/genética , Mioglobina/metabolismoRESUMO
Myoglobin is one of the early biomarkers for acute myocardial infarction. Recently, we have screened an antibody with unique rapid reaction kinetics toward human myoglobin antigen. Antibodies with rapid reaction kinetics are thought to be an early IgG form produced during early stage of in vivo immunization. We produced a recombinant scFv fragment for the premature antibody from Escherichia coli using refolding technology. The scFv gene was constructed by connection of the V(H)-V(L) sequence with a (Gly4Ser)3 linker. The scFv fragment without the pelB leader sequence was expressed at a high level, but the solubility was extremely low. A high concentration of 8 M urea was used for denaturation. The dilution refolding process in the presence of arginine and the redox reagents GSH and GSSH successfully produced a soluble scFv protein. The resultant refolded scFv protein showed association and dissociation values of 9.32 × 10â»4 M⻹·s⻹ and 6.29 × 10⻳ s⻹, respectively, with an affinity value exceeding 107 M⻹ (k(on)/k(off)), maintaining the original rapid reaction kinetics of the premature antibody. The refolded scFv could provide a platform for protein engineering for the clinical application for diagnosis of heart disease and the development of a continuous biosensor.
Assuntos
Mioglobina/imunologia , Redobramento de Proteína , Anticorpos de Cadeia Única/química , Humanos , CinéticaRESUMO
Nanostructured surfaces emerge as a new class of material for capture and separation of cell populations including primary immune cells and disseminating rare tumor cells, but the underlying mechanism remains elusive. Although it has been speculated that nanoscale topological structures on cell surface are involved in the cell capture process, there are no studies that systematically analyze the relation between cell surface structures and the capture efficiency. Here we report on the first mechanistic study by quantifying the morphological parameters of cell surface nanoprotrusions, including filopodia, lamellipodia, and microvilli in the early stage of cell capture (< 20 min) in correlation to the efficiency of separating primary T lymphocytes. This was conducted by using a set of nanohole arrays (NHAs) with varying hole and pitch sizes. Our results showed that the formation of filopodia (e.g., width of filopodia and the average number of the filopodial filaments per cell) depends on the feature size of the nanostructures and the cell separation efficiency is strongly correlated to the number of filopodial fibers, suggesting a possible role of early stage mechanosensing and cell spreading in determining the efficiency of cell capture. In contrast, the length of filopodial filaments was less significantly correlated to the cell capture efficiency and the nanostructure dimensions of the NHAs. This is the first mechanistic study on nanostructure-based immune cell capture and provides new insights to not only the biology of cell-nanomaterial interaction but also the design of new rare cell capture technologies with improved efficiency and specificity.
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Nanopartículas/química , Nanopartículas/ultraestrutura , Nanoporos/ultraestrutura , Poliestirenos/química , Linfócitos T/química , Animais , Células Cultivadas , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL , Conformação Molecular , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
Despite significant improvement in separation efficiency using nanostructure-based platforms, the mechanism underlying the high efficiency of rare cell capture remains elusive. Here we report on the first mechanistic study by developing highly controlled nanostructures to investigate cell surface nanomorphology to better understand the cellular response of CD4(+) T-lymphocytes in contact with nanostructured surfaces and to elucidate key mechanisms for enhancing separation efficiency. Our results showed that actin-rich filopodia protruded from T-cells in the early stage of cell capture (<20 min), demonstrate the different morphologies in response to various quartz nanopillar (QNP) arrays functionalized with streptavidin and the generation of sufficient adhesion sites for rendering more stable binding through three-dimensional local nanotopographic interactions between filopodia-QNPs and cell-substrate, leading to synergistic effects for enhancing cell-capture efficiency. This responsive mechanism of T-cells on nanotopographic templates provides new insights to understand the enhanced cell-capture efficiency and specificity from the primary cell suspension on nanostructured substrates.
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Linfócitos T CD4-Positivos/ultraestrutura , Pseudópodes/ultraestrutura , Animais , Linfócitos T CD4-Positivos/química , Proteínas de Membrana/química , Camundongos , Camundongos Endogâmicos C57BL , Nanoestruturas , Pseudópodes/química , Quartzo , Baço/citologiaRESUMO
TMPRSS4 is a novel type II transmembrane serine protease that is highly expressed on the cell surface in pancreatic, thyroid, colon, and other cancer tissues. Previously, we demonstrated that TMPRSS4 mediates cancer cell invasion, epithelial-mesenchymal transition, and metastasis and that increased TMPRSS4 expression correlates with colorectal cancer progression. We also demonstrated that TMPRSS4 upregulates urokinase-type plasminogen activator (uPA) gene expression to induce cancer cell invasion. However, it remains unknown how proteolytic activity of TMPRSS4 contributes to invasion. In this study, we report that TMPRSS4 directly converted inactive pro-uPA into the active form through its proteolytic activity. Analysis of conditioned medium from cells overexpressing TMPRSS4 demonstrated that the active TMPRSS4 protease domain is released from the cells and is associated with the plasma membrane. Furthermore, TMPRSS4 could increase pro-uPA-mediated invasion in a serine proteolytic activity-dependent manner. These observations suggest that TMPRSS4 is an upstream regulator of pro-uPA activation. This study provides valuable insights into the proteolytic function of TMPRSS4 as well as mechanisms for the control of invasion.
Assuntos
Proteínas de Membrana/metabolismo , Invasividade Neoplásica/fisiopatologia , Serina Endopeptidases/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática , Células HEK293 , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Invasividade Neoplásica/genética , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/genética , Regulação para Cima , Ativador de Plasminogênio Tipo Uroquinase/genéticaRESUMO
TMPRSS4 is a novel type II transmembrane serine protease that is highly expressed in pancreatic, thyroid, colon, and other cancer tissues. Previously, we demonstrated that TMPRSS4 mediates tumor cell invasion, migration, and metastasis. However, the mechanisms by which TMPRSS4 contributes to invasion are not fully understood. Here, we demonstrated that TMPRSS4 induced the transcription of the urokinase-type plasminogen activator (uPA) gene through activating the transcription factors Sp1, Sp3, and AP-1 in mainly a JNK-dependent manner and that the induction of uPA was required for TMPRSS4-mediated cancer cell invasion and signaling events. In addition, the uPA receptor was involved in TMPRSS4-induced signaling activation and subsequent uPA expression probably through its association with TMPRSS4 on the cell surface. Immunohistochemical analysis showed that uPA expression was significantly correlated with TMPRSS4 expression in human lung and prostate cancers. These observations suggest that TMPRSS4 is an important regulator of uPA gene expression; the upregulation of uPA by TMPRSS4 contributes to invasion and may represent a novel mechanism for the control of invasion.
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Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas de Membrana/metabolismo , Serina Endopeptidases/metabolismo , Transdução de Sinais , Regulação para Cima , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Interferência de RNA , Receptores de Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Serina Endopeptidases/genética , Fator de Transcrição Sp1/antagonistas & inibidores , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp3/genética , Fator de Transcrição Sp3/metabolismo , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/genéticaRESUMO
The hypoxia inducible factor (HIF) system is central to the signaling of low oxygen (hypoxia) in animals. The levels of HIF-α isoforms are regulated in an oxygen-dependent manner by the activity of the HIF prolyl-hydroxylases (PHD or EGLN enzymes), which are Fe(II) and 2-oxoglutarate (2OG) dependent oxygenases. Here, we describe biochemical, crystallographic, cellular profiling, and animal studies on PHD inhibitors including selectivity studies using a representative set of human 2OG oxygenases. We identify suitable probe compounds for use in studies on the functional effects of PHD inhibition in cells and in animals.
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Compostos Heterocíclicos/síntese química , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/química , Animais , Animais Geneticamente Modificados , Bioensaio , Linhagem Celular , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Transdução de Sinais , Bibliotecas de Moléculas Pequenas/farmacologia , Peixe-Zebra/embriologia , Peixe-Zebra/genéticaRESUMO
BACKGROUND: siRNA is a new tool for treatment of diseases such as cancer. However, it cannot be used directly due to rapid degradation in body fluid and blood stream; therefore, vectors are necessary for protection of siRNA against RNases and also for its precise delivery to the target cells. Since viral vector causes cancer and immune response in the host, liposomes are more preferable vectors. Liposome size is an important factor for longer circulation time. Extrusion minimizes the liposome size; however, it leads to less liposome encapsulation. Moreover, it changes structure of asymmetric liposomes. FINDINGS: Here, ethanol treatment is introduced as a method of liposome size optimization that significantly decreases the liposome size without any effect on liposome encapsulation and its asymmetric structure formulation. For this, after liposome formation while there is some ether in solution, ethanol was added to fresh liposomes (25 and 30 percent of total liposomes volume) and liposomes were incubated at room temperature with mild agitation for 20 minutes. Finally, the extra ethanol and ether were removed by dialysis. CONCLUSION: Utilizing this method the liposome size was successfully decreased about 100 nm. The size of optimized liposomes (200 nm) is quite suitable for in vivo target delivery.
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Cell penetrating peptides (CPPs) have been used to transport macromolecules into cells. Most CPPs have properties such as a strong polycationic charge, amphipathic basic, and hydrophobicity. In this study, we designed the peptides with multiple motifs composed of RGD and its analogs to induce integrin-mediated endocytosis as well as endosomal escape by forming an amphipathic helix in acidic endosomes. These peptides were proved less toxic to animal cells than those without acidic residues. Unexpectedly, peptide conjugated liposomes could penetrate into cells regardless of integrins. The replacement of all aspartic acids by glutamic acids did not prevent the peptide-mediated liposome uptake, and the higher basic and leucine contents enhanced the gene silencing activity of siRNA encapsulated in the liposomes. The peptide is considered to be a new type of CPP which can be used for drug delivery.
Assuntos
Peptídeos Penetradores de Células/metabolismo , Inativação Gênica , Oligopeptídeos/química , RNA Interferente Pequeno/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Ácido Aspártico/química , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/farmacologia , Ácido Glutâmico/química , Humanos , Lipossomos , Camundongos , Dados de Sequência Molecular , Células NIH 3T3 , RNA Interferente Pequeno/genéticaRESUMO
Inhibition of the hypoxia-inducible factor (HIF) prolyl hydroxylases (PHD or EGLN enzymes) is of interest for the treatment of anemia and ischemia-related diseases. Most PHD inhibitors work by binding to the single ferrous ion and competing with 2-oxoglutarate (2OG) co-substrate for binding at the PHD active site. Non-specific iron chelators also inhibit the PHDs, both in vitro and in cells. We report the identification of dual action PHD inhibitors, which bind to the active site iron and also induce the binding of a second iron ion at the active site. Following analysis of small-molecule iron complexes and application of non-denaturing protein mass spectrometry to assess PHD2·iron·inhibitor stoichiometry, selected diacylhydrazines were identified as PHD2 inhibitors that induce the binding of a second iron ion. Some compounds were shown to inhibit the HIF hydroxylases in human hepatoma and renal carcinoma cell lines.