RESUMO
Cortical neurons in dissociated cultures are an indispensable model system for pharmacological research that provides insights into chemical responses in well-defined environments. However, cortical neurons plated on homogeneous substrates develop an unstructured network that exhibits excessively synchronized activity, which occasionally masks the consequences induced by external substances. Here, we show that hyperactivity and excessive synchrony in cultured cortical networks can be effectively suppressed by growing neurons in microfluidic devices. These devices feature a hierarchically modular design that resembles the in vivo network. We focused on interleukin-6, a pro-inflammatory cytokine, and assessed its acute and chronic effects. Fluorescence calcium imaging of spontaneous neural activity for up to 20 days of culture showed detectable modulation of collective activity events and neural correlation in micropatterned neurons, which was not apparent in neurons cultured on homogeneous substrates. Our results indicate that engineered neuronal networks provide a unique platform for detecting and understanding the fundamental effects of biochemical compounds on neuronal networks.
Assuntos
Citocinas , Interleucina-6 , Interleucina-6/farmacologia , Citocinas/farmacologia , Potenciais de Ação/fisiologia , Células Cultivadas , Rede Nervosa , NeurôniosRESUMO
BACKGROUND: Spinal cord injury (SCI) in young adults leads to severe sensorimotor disabilities as well as slowing of growth. Systemic pro-inflammatory cytokines are associated with growth failure and muscle wasting. Here we investigated whether intravenous (IV) delivery of small extracellular vesicles (sEVs) derived from human mesenchymal stem/stromal cells (MSC) has therapeutic effects on body growth and motor recovery and can modulate inflammatory cytokines following severe SCI in young adult rats. METHODS: Contusional SCI rats were randomized into three different treatment groups (human and rat MSC-sEVs and a PBS group) on day 7 post-SCI. Functional motor recovery and body growth were assessed weekly until day 70 post-SCI. Trafficking of sEVs after IV infusions in vivo, the uptake of sEVs in vitro, macrophage phenotype at the lesion and cytokine levels at the lesion, liver and systemic circulation were also evaluated. RESULTS: An IV delivery of both human and rat MSC-sEVs improved functional motor recovery after SCI and restored normal body growth in young adult SCI rats, indicating a broad therapeutic benefit of MSC-sEVs and a lack of species specificity for these effects. Human MSC-sEVs were selectively taken up by M2 macrophages in vivo and in vitro, consistent with our previous observations of rat MSC-sEV uptake. Furthermore, the infusion of human or rat MSC-sEVs resulted in an increase in the proportion of M2 macrophages and a decrease in the production of the pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-6 at the injury site, as well as a reduction in systemic serum levels of TNF-α and IL-6 and an increase in growth hormone receptors and IGF-1 levels in the liver. CONCLUSIONS: Both human and rat MSC-sEVs promote the recovery of body growth and motor function after SCI in young adult rats possibly via the cytokine modulation of growth-related hormonal pathways. Thus, MSC-sEVs affect both metabolic and neurological deficits in SCI.
Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Humanos , Ratos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Células-Tronco Mesenquimais/metabolismo , Traumatismos da Medula Espinal/terapia , Vesículas Extracelulares/metabolismo , Citocinas/metabolismo , Interleucina-6/metabolismoRESUMO
New cell sources for the research and therapy of organ failure could significantly alleviate the shortage of donor livers that are available to patients who suffer from liver disease. Liver carcinoma derived cells, or hepatoma cells, are the ideal cells for developing bioartificial liver systems. Such cancerous liver cells are easy to prepare in large quantities and can be maintained over long periods under standard culture conditions, unlike primary hepatocytes. However, hepatoma cells possess only a fraction of the functions of primary hepatocytes. In a previous study, by transducing cells with liver-enriched transcription factors that could be inducibly overexpressed-hepatocyte nuclear factor (HNF)1α, HNF1ß, HNF3ß [FOXA2], HNF4α, HNF6, CCAAT/enhancer binding protein (C/EBP)α, C/EBPß and C/EBPγ-we created mouse hepatoma cells with high liver-specific gene expression called the Hepa/8F5 cell line. In the present study, we performed functional and genetic analyses to characterize the Hepa/8F5 cell line. Further, in three-dimensional cultures, the function of these cells improved significantly compared to parental cells. Ultimately, these cells might become a new resource that can be used in basic and applied hepatic research.
Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Hepatócitos/metabolismo , Hepatócitos/patologia , Neoplasias Hepáticas/patologia , Camundongos , Especificidade de ÓrgãosRESUMO
The self-assembled bilayer lipid membrane (BLM) is the basic component of the cell membrane. The reconstitution of ion channel proteins in artificially formed BLMs represents a well-defined system for the functional analysis of ion channels and screening the effects of drugs that act on them. However, because BLMs are unstable, this limits the experimental throughput of BLM reconstitution systems. Here we report on the formation of mechanically stable solvent-free BLMs in microfabricated apertures with defined nano- and micro-tapered edge structures. The role of such nano- and micro-tapered structures on the stability of the BLMs was also investigated. Finally, this BLM system was combined with a cell-free synthesized human ether-a-go-go-related gene channel, a cardiac potassium channel whose relation to arrhythmic side effects following drug treatment is well recognized. Such stable BLMs as these, when combined with a cell-free system, represent a potential platform for screening the effects of drugs that act on various ion-channel genotypes.
Assuntos
Canais de Potássio Éter-A-Go-Go/metabolismo , Bicamadas Lipídicas/metabolismo , Sistemas Microeletromecânicos/métodos , Membrana Celular/metabolismo , Canais de Potássio Éter-A-Go-Go/fisiologia , Humanos , Canais Iônicos/metabolismo , Bicamadas Lipídicas/síntese química , Microtecnologia/métodos , Canais de Potássio/metabolismo , Canais de Potássio/fisiologia , Compostos de Silício , SolventesRESUMO
Only free drugs have been believed to be carried into tissues through active or passive transport. However, considering that lipoproteins function as carriers of serum lipids such as cholesterol and triglycerides, we hypothesized that lipoproteins can associate with certain drugs and mediate their transport into tissues in lipid-associated form. Here, in vitro and in vivo studies with low density lipoprotein receptor (LDLR)-overexpressing or -knockdown cells and wild-type or LDLR-mutant mice were used to show the association of various drugs with lipoproteins and the uptake of lipoprotein-associated drugs through a lipoprotein receptor-mediated process. In clinical studies, investigation of the effect of lipoprotein apheresis on serum drug concentrations in patients with familial hypercholesterolemia demonstrated that lipoprotein-mediated drug transport occurs in humans as well as in mice. These findings represent a new concept regarding the transport and metabolism of drugs in the body and suggest that the role of lipoprotein-mediated drug transport should be considered when developing effective and safe pharmacotherapies.
Assuntos
Portadores de Fármacos , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Preparações Farmacêuticas/metabolismo , Anlodipino/farmacocinética , Animais , Transporte Biológico , Colesterol/sangue , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/metabolismo , Masculino , Camundongos , Ligação Proteica , Receptores de LDL/genética , Receptores de LDL/metabolismo , Ticlopidina/farmacocinéticaRESUMO
The main constituent of green tea, (-)-Epigallocatechin-3-O-gallate (EGCG), is known to have cancer-specific chemopreventive effects. In the present work, we investigated how EGCG suppresses cell adhesion by comparing the adhesion of human pancreatic cancer cells (AsPC-1 and BxPC-3) and their counterpart, normal human embryonic pancreas-derived cells (1C3D3), in catechin-containing media using organosilane monolayer templates (OMTs). The purpose of this work is (1) to evaluate the quantitativeness in the measurement of cell adhesion with the OMT and (2) to show how green-tea catechins suppress cell adhesion in a cancer-specific manner. For the first purpose, the adhesion of cancer and normal cells was compared using the OMT. The cell adhesion in different type of catechins such as EGCG, (-)-Epicatechin-3-O-gallate (ECG) and (-)-Epicatechin (EC) was also evaluated. The measurements revealed that the anti-adhesion effect of green-tea catechins is cancer-specific, and the order is EGCGâ«ECG>EC. The results agree well with the data reported to date, showing the quantitativeness of the new method. For the second purpose, the contact area of cells on the OMT was measured by reflection interference contrast microscopy. The cell-OMT contact area of cancer cells decreases with increasing EGCG concentration, whereas that of normal cells remains constant. The results reveal a twofold action of EGCG on cancer cell adhesion-suppressing cell attachment to a candidate adhesion site and decreasing the contact area of the cells-and validates the use of OMT as a tool for screening cancer cell adhesion.
Assuntos
Catequina/análogos & derivados , Adesão Celular/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Catequina/administração & dosagem , Catequina/química , Linhagem Celular Tumoral , Humanos , Neoplasias Pancreáticas/patologia , Chá/químicaRESUMO
Adhesion of cancer cells with different metastatic potential and anticancer drug resistance has been quantitatively evaluated by using self-assembled monolayer (SAM)-patterned substrates and reflection interference contrast microscopy (RICM). Cell-adhesive SAM spots with optimized diameter could prevent cell-cell adhesion and thus allowed the systematic evaluation of statistically reliable numbers of contact area between single cancer cells and substrates by RICM. The statistical image analysis revealed that highly metastatic mouse melanoma cells showed larger contact area than lowly metastatic cells. We also found that both cancer cell types exhibited distinct transition from the "strong" to "weak" adhesion states with increase in the concentration of (-)-epigallocatechin gallate (EGCG), which is known to exhibit cancer preventive activity. Mathematical analysis of the adhesion transition revealed that adhesion of the highly metastatic mouse melanoma cells showed more EGCG tolerance than that of lowly metastatic cells. Moreover, time-lapse RICM observation revealed that EGCG weakened cancer cell adhesion in a stepwise manner, probably via focal adhesion complex. These results clearly indicate that contact area can be used as a quantitative measure for the determination of cancer phenotypes and their drug resistance, which will provide physical insights into the mechanism of cancer metastasis and cancer prevention.
Assuntos
Anticarcinógenos/farmacologia , Catequina/análogos & derivados , Adesão Celular/efeitos dos fármacos , Microscopia de Interferência/métodos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Catequina/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/patologiaRESUMO
Hippocampal granule cells (GCs) are generated throughout the lifetime and are properly incorporated into the innermost region of the granule cell layer (GCL). Hypotheses for the well-regulated lamination of newly generated GCs suggest that polysialic acid (PSA) is present on the GC surface to modulate GC-to-GC interactions, regulating the process of GC migration; however, direct evidence of this involvement is lacking. We show that PSA facilitates the migration of newly generated GCs and that the activity of N-acetyl-α-neuraminidase 1 (NEU1, sialidase 1) cleaves PSA from immature GCs, terminating their migration in the innermost GCL. Developing a migration assay of immature GCs in vitro, we found that the pharmacological depletion of PSA prevents the migration of GCs, whereas the inhibition of PSA degradation with a neuraminidase inhibitor accelerates this migration. We found that NEU1 is highly expressed in immature GCs. The knockdown of NEU1 in newly generated GCs in vivo increased PSA presence on these cells, and attenuated the proper termination of GC migration in the innermost GCL. In conclusion, this study identifies a novel mechanism that underlies the proper lamination of newly generated GCs through the modulation of PSA presence by neuronal NEU1.
Assuntos
Hipocampo/metabolismo , Neuraminidase/metabolismo , Neurônios/metabolismo , Ácidos Siálicos/metabolismo , Animais , Movimento Celular/fisiologia , Hipocampo/citologia , Neurogênese , Neurônios/citologia , Ratos , Ratos Sprague-DawleyRESUMO
Organic contaminants adsorbed on the surface of titanium dioxide (TiO2) can be decomposed by photocatalysis under ultraviolet (UV) light. Here we describe a novel protocol employing the TiO2 photocatalysis to locally alter cell affinity of the substrate surface. For this experiment, a thin TiO2 film was sputter-coated on a glass coverslip, and the TiO2 surface was subsequently modified with an organosilane monolayer derived from octadecyltrichlorosilane (OTS), which inhibits cell adhesion. The sample was immersed in a cell culture medium, and focused UV light was irradiated to an octagonal region. When a neuronal cell line PC12 cells were plated on the sample, cells adhered only on the UV-irradiated area. We further show that this surface modification can also be performed in situ, i.e., even when cells are growing on the substrate. Proper modification of the surface required an extracellular matrix protein collagen to be present in the medium at the time of UV irradiation. The technique presented here can potentially be employed in patterning multiple cell types for constructing coculture systems or to arbitrarily manipulate cells under culture.
Assuntos
Proteínas da Matriz Extracelular/química , Neurônios/citologia , Alicerces Teciduais , Titânio/química , Titânio/efeitos da radiação , Animais , Materiais Biocompatíveis/química , Catálise , Adesão Celular/fisiologia , Vidro/química , Células PC12 , Processos Fotoquímicos , Ratos , Silanos/química , Propriedades de Superfície , Raios Ultravioleta , Água/químicaRESUMO
Studies of human brain malformations, such as lissencephaly and double cortex, have revealed the importance of neuronal migration during cortical development. Afadin, a membrane scaffolding protein, regulates the formation of adherens junctions (AJs) and cell migration to form and maintain tissue structures. Here, we report that mice with dorsal telencephalon-specific ablation of afadin gene exhibited defects similar to human double cortex, in which the heterotopic cortex was located underneath the normotopic cortex. The normotopic cortex of the mutant mice was arranged in the pattern similar to the cortex of the control mice, while the heterotopic cortex was disorganized. As seen in human patients, double cortex in the mutant mice was formed by impaired neuronal migration during cortical development. Genetic ablation of afadin in the embryonic cerebral cortex disrupted AJs of radial glial cells, likely resulting in the retraction of the apical endfeet from the ventricular surface and the dispersion of radial glial cells from the ventricular zone to the subventricular and intermediate zones. These results indicate that afadin is required for the maintenance of AJs of radial glial cells and that the disruption of AJs might cause an abnormal radial scaffold for neuronal migration. In contrast, the proliferation or differentiation of radial glial cells was not significantly affected. Taken together, these findings indicate that afadin is required for the maintenance of the radial glial scaffold for neuronal migration and that the genetic ablation of afadin leads to the formation of double cortex.
Assuntos
Movimento Celular/fisiologia , Córtex Cerebral/embriologia , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/fisiopatologia , Cinesinas/deficiência , Miosinas/deficiência , Neuroglia/fisiologia , Neurônios/fisiologia , Animais , Animais Recém-Nascidos , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/patologia , Modelos Animais de Doenças , Imunofluorescência , Cinesinas/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Miosinas/genética , Neuroglia/patologia , Neurônios/patologiaRESUMO
We demonstrate a novel application of TiO2 photocatalysis for modifying the cell affinity of a scaffold surface in a cell-culture environment. An as-deposited octadecyltrichlorosilane self-assembled monolayer (OTS SAM) on TiO2 was found to be hydrophobic and stably adsorbed serum albumins that blocked subsequent adsorption of other proteins and cells. Upon irradiation of ultraviolet (UV) light, OTS molecules were decomposed and became permissive to the adhesion of PC12 cells via adsorption of an extracellular matrix protein, collagen. Optimal UV dose was 200 J cm(-2) for OTS SAM on TiO2. The amount of collagen adsorption decreased when excessive UV light was irradiated, most likely due to the surface being too hydrophilic to support its adsorption. This UV-induced modification required TiO2 to be present under the SAM and hence is a result of TiO2 photocatalysis. The UV irradiation for surface modification can be performed before cell plating or during cell culture. We also demonstrate that poly(ethylene glycol) SAM can also be patterned with this method, indicating that it is applicable to both hydrophobic and hydrophilic SAMs. This method provides a unique tool for fabricating cell microarrays and studying dynamical properties of living cells.
Assuntos
Silanos/química , Engenharia Tecidual/instrumentação , Alicerces Teciduais/química , Animais , Catálise/efeitos da radiação , Adesão Celular , Interações Hidrofóbicas e Hidrofílicas , Células PC12 , Ratos , Propriedades de Superfície , Raios UltravioletaRESUMO
The causative parasite of alveolar echinococcosis, Echinococcus multilocularis, maintains its life cycle between red foxes (Vulpes vulples, the definitive hosts) and voles (the intermediate hosts) in Hokkaido, Japan. Primates, including humans, and some other mammal species can be infected by the accidental ingestion of eggs in the feces of red foxes. In August 2011, a 6-year-old zoo-raised female Diana monkey (Cercopithecus diana) died from alveolar echinococcosis. E. multilocularis infection was confirmed by histopathological examination and detection of the E. multilocularis DNA by polymerase chain reaction (PCR). A field survey in the zoo showed that fox intrusion was common, and serodiagnosis of various nonhuman primates using western blotting detected a case of a 14-year-old female Celebes crested macaque (Macaca nigra) that was weakly positive for E. multilocularis. Computed tomography revealed only one small calcified lesion (approximately 8mm) in the macaque's liver, and both western blotting and enzyme-linked immunosorbent assay (ELISA) showed a gradual decline of antibody titer. These findings strongly suggest that the animal had recovered spontaneously. Until this study, spontaneous recovery from E. multilocularis infection in a nonhuman primate had never been reported.
Assuntos
Animais de Zoológico , Cercopithecus , Equinococose Hepática/veterinária , Echinococcus multilocularis/isolamento & purificação , Macaca , Doenças dos Macacos/parasitologia , Animais , Western Blotting/veterinária , Equinococose , Equinococose Hepática/parasitologia , Ensaio de Imunoadsorção Enzimática/veterinária , Evolução Fatal , Feminino , Japão , Reação em Cadeia da Polimerase/veterinária , Remissão Espontânea , Tomografia Computadorizada por Raios X/veterináriaRESUMO
The antiplatelet drug, ticlopidine (TIC), reportedly causes cholestatic liver injuries. The present study analyzed the effect of TIC on bile formation, revealing that the biliary secretion of phospholipids was significantly decreased in TIC-administered Sprague Dawley (SD) rats. However, the effect of TIC on biliary phospholipids was not observed in SD rats pretreated with diethylaminoethyl diphenylpropylacetate that inhibits cytochrome P450s (P450), or in Eisai hyperbilirubinemic rats (EHBR) lacking functional multidrug resistance-associated protein 2 (MRP2/ABCC2). These results suggest that glutathione-conjugated TIC metabolites (TIC-SGs), which were formed in the liver after P450s-mediated metabolism and were excreted extensively into bile by MRP2, mediated the observed alterations of the bile composition. Administration of TIC caused significant liver injuries in SD rats, with decreased biliary phospholipids, but not in EHBR, consistent with the in vitro observation that phospholipid-bile acid-mixed micelles moderated the cytotoxic effects of bile acids. Further analyses revealed that TIC-SGs did not directly inhibit multidrug resistance 3 P-glycoprotein (MDR3/ABCB4)-mediated phosphatidylcholine efflux in vitro. Because the diminished biliary secretion of phospholipids with TIC administration was restored by taurocholate infusion in SD rats, the decreased biliary concentration of bile acids, due to the stimulation of bile acid-independent bile flow driven by TIC-SGs, might have indirectly attenuated phospholipid secretion. In conclusion, extensive biliary excretion of TIC-SGs decreased the biliary secretion of phospholipids, which might have increased the risk of TIC-induced cholestatic liver injury.
Assuntos
Bile/efeitos dos fármacos , Sistema Biliar/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Colestase/metabolismo , Glutationa/metabolismo , Fosfolipídeos/metabolismo , Ticlopidina/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Bile/metabolismo , Sistema Biliar/metabolismo , Transporte Biológico/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Fígado/efeitos dos fármacos , Fígado/lesões , Fígado/metabolismo , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Ratos , Ratos Sprague-Dawley , Ácido Taurocólico/farmacologia , Ticlopidina/metabolismoRESUMO
Mutations in genes for any of the six subunits of NADPH oxidase cause chronic granulomatous disease (CGD), but almost 2/3 of CGD cases are caused by mutations in the X-linked CYBB gene, also known as NAD (P) H oxidase 2. Approximately 260 patients with CGD have been reported in Japan, of whom 92 were shown to have mutations of the CYBB gene and 16 to have chromosomal deletions. However, there has been very little detailed analysis of the range of the deletion or close understanding of the disease based on this. We therefore analyzed genomic rearrangements in X-linked CGD using array comparative genomic hybridization analysis, revealing the extent and the types of the deletion genes. The subjects were five Japanese X-linked CGD patients estimated to have large base deletions of 1 kb or more in the CYBB gene (four male patients, one female patient) and the mothers of four of those patients. The five Japanese patients were found to range from a patient exhibiting deletions only of the CYBB gene to a female patient exhibiting an extensive DNA deletion and the DMD and CGD phenotype manifested. Of the other three patients, two exhibited CYBB, XK, and DYNLT3 gene deletions. The remaining patient exhibited both a deletion encompassing DNA subsequent to the CYBB region following intron 2 and the DYNLT3 gene and a complex copy number variation involving the insertion of an inverted duplication of a region from the centromere side of DYNLT3 into the deleted region.
Assuntos
Cromossomos Humanos X/genética , Variações do Número de Cópias de DNA , Ligação Genética , Doença Granulomatosa Crônica/genética , Deleção de Sequência , Centrômero , Deleção Cromossômica , Hibridização Genômica Comparativa , Dineínas/genética , Feminino , Duplicação Gênica , Humanos , Lactente , Íntrons , Japão , Masculino , Glicoproteínas de Membrana/genética , Mães , Mutação , NADPH Oxidase 2 , NADPH Oxidases/genética , Fenótipo , Análise de Sequência de DNA , Inversão de SequênciaRESUMO
Prenylated polyphenols are secondary metabolites beneficial for human health because of their various biological activities. Metabolic engineering was performed using Streptomyces and Sophora flavescens prenyltransferase genes to produce prenylated polyphenols in transgenic legume plants. Three Streptomyces genes, NphB, SCO7190, and NovQ, whose gene products have broad substrate specificity, were overexpressed in a model legume, Lotus japonicus, in the cytosol, plastids or mitochondria with modification to induce the protein localization. Two plant genes, N8DT and G6DT, from Sophora flavescens whose gene products show narrow substrate specificity were also overexpressed in Lotus japonicus. Prenylated polyphenols were undetectable in these plants; however, supplementation of a flavonoid substrate resulted in the production of prenylated polyphenols such as 7-O-geranylgenistein, 6-dimethylallylnaringenin, 6-dimethylallylgenistein, 8-dimethylallynaringenin, and 6-dimethylallylgenistein in transgenic plants. Although transformants with the native NovQ did not produce prenylated polyphenols, modification of its codon usage led to the production of 6-dimethylallylnaringenin and 6-dimethylallylgenistein in transformants following naringenin supplementation. Prenylated polyphenols were not produced in mitochondrial-targeted transformants even under substrate feeding. SCO7190 was also expressed in soybean, and dimethylallylapigenin and dimethylallyldaidzein were produced by supplementing naringenin. This study demonstrated the potential for the production of novel prenylated polyphenols in transgenic plants. In particular, the enzymatic properties of prenyltransferases seemed to be altered in transgenic plants in a host species-dependent manner.
Assuntos
Dimetilaliltranstransferase/metabolismo , Glycine max/enzimologia , Lotus/enzimologia , Engenharia Metabólica/métodos , Plantas Geneticamente Modificadas/enzimologia , Polifenóis/biossíntese , Dimetilaliltranstransferase/genética , Flavanonas/administração & dosagem , Lotus/genética , Plantas Geneticamente Modificadas/genética , Prenilação/genética , Sophora/enzimologia , Sophora/genética , Glycine max/genética , Streptomyces/enzimologia , Streptomyces/genética , Especificidade por SubstratoRESUMO
The exact molecular mechanism by which epigallocatechin gallate (EGCG) suppresses human pancreatic cancer cell proliferation is unclear. We show here that EGCG-treated pancreatic cancer cells AsPC-1 and BxPC-3 decrease cell adhesion ability on micro-pattern dots, accompanied by dephosphorylations of both focal adhesion kinase (FAK) and insulin-like growth factor-1 receptor (IGF-1R) whereas retained the activations of mitogen-activated protein kinase and mammalian target of rapamycin. The growth of AsPC-1 and BxPC-3 cells can be significantly suppressed by EGCG treatment alone in a dose-dependent manner. At a dose of 100 µM which completely abolishes activations of FAK and IGF-1R, EGCG suppresses more than 50% of cell proliferation without evidence of apoptosis analyzed by PARP cleavage. Finally, the MEK1/2 inhibitor U0126 enhances growth-suppressive effect of EGCG. Our data suggests that blocking FAK and IGF-1R by EGCG could prove valuable for targeted therapy, which can be used in combination with other therapies, for pancreatic cancer.
Assuntos
Antineoplásicos/farmacologia , Catequina/análogos & derivados , Quinase 1 de Adesão Focal/antagonistas & inibidores , Neoplasias Pancreáticas/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Chá , Antineoplásicos/uso terapêutico , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose/fisiologia , Catequina/metabolismo , Catequina/farmacologia , Catequina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Pancreáticas/tratamento farmacológicoRESUMO
BACKGROUND: Interaction between eosinophil alpha4 integrin and vascular cell adhesion molecule 1 (VCAM-1) expressed on activated endothelial cells may be a key step in the selective recruitment of eosinophils from the circulation to sites of inflammation. OBJECTIVE: To investigate the factor(s) that induces transmigration of eosinophils after firm adhesion via the alpha4 integrin/VCAM-1 pathway. METHODS: We examined the effects of a variety of inflammatory mediators on the migration of eosinophils across recombinant human (rh) intracellular adhesion molecule 1- or rhVCAM-1-coated Transwell filters or VCAM-1-expressing human pulmonary microvascular endothelial cells (HPMECs) that had been stimulated with interleukin 4 (IL-4) and tumor necrosis factor alpha. The number of eosinophils that had transmigrated was evaluated by measuring eosinophil peroxidase activity. RESULTS: The CC chemokines RANTES (regulated on activation, normal T-cell expressed, and secreted), eotaxin, eotaxin 2, monocyte chemotactic protein 3 (MCP-3), and MCP-4 each increased eosinophil transmigration across rhVCAM-1-coated filters compared with fetal calf serum-blocked or rh intracellular adhesion molecule 1-coated filters (P < .01). On the other hand, platelet-activating factor, C5a, formyl-methionyl-leucil-phenylalanine, granulocyte-macrophage colony-stimulating factor, IL-5, and IL-8 did not enhance migration across rhVCAM-1. The enhancement of migration by RANTES in the presence of rhVCAM-1 was blocked by an anti-alpha4 integrin monoclonal antibody. CC chemokines augmented eosinophil transmigration across VCAM-1-expressing HPMECs compared with resting HPMECs (P < .01). Conversely, the transmigration induced by platelet-activating factor, C5a, formyl-methionyl-leucil-phenylalanine, or IL-8 was not modified by the expression of VCAM-1 on HPMECs. CONCLUSIONS: CC chemokines induce transendothelial migration of eosinophils after interaction between eosinophil alpha4 integrin and endothelial VCAM-1.
Assuntos
Movimento Celular/efeitos dos fármacos , Quimiocinas CC/farmacologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Integrina alfa4/metabolismo , Interleucina-4/farmacologia , Proteínas Recombinantes/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
The presence of multiple small nodular shadows on a routine chest radiograph was noticed in a 56-year-old woman who had undergone a left mastectomy on the diagnosis of breast cancer 8 years before. Chest CT films revealed small nodules scattered beneath the pleura mainly in both lower lobes. A biopsy was performed during video-assisted thoracoscopy to rule out metastasis from breast cancer. Biopsy specimens showed spindle--or oval-shaped cells arranged in nests associated with a dedicated network of capillaries. These findings were compatible with minute meningothelium-like nodules (MN). The pathogenesis of MN is still unknown. It is common in elderly women, and the prognosis is excellent without any treatment. MN is an important disease in the differential diagnosis of multiple nodular shadows found on chest CT.