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1.
Genes Cells ; 25(4): 257-269, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32012396

RESUMEN

Most physiological changes follow a daily cycle in animals because their circadian rhythm is adjusted to and synchronized with sunlight. In particular, the circadian rhythm affects liver functions, including pharmacokinetics and metabolism. The influence of circadian rhythm has not been included in hepatotoxicity assays used in drug discovery and development. In this study, the contribution of circadian rhythm was investigated in acetaminophen-induced hepatotoxicity in mice and primary cultured hepatocytes. Hepatotoxicity was induced via the intraperitoneal administration of acetaminophen to a greater extent at night than during the day in mice. The sensitivity of acetaminophen-induced hepatotoxicity was consistent with the expression levels of acetaminophen-metabolizing enzyme and circadian genes. The host-derived circadian rhythm was still evident in the primary cultured hepatocytes within a day after their isolation from the liver. Primary cultured hepatocytes isolated at night were significantly more sensitive to acetaminophen than those isolated during the day. The sensitivity toward acetaminophen-induced hepatotoxicity depended on the circadian rhythm of the expression of acetaminophen-metabolizing genes and intracellular glutathione levels in primary cultured hepatocytes. These results obtained from cultured cells correspond to those in mice, suggesting that the timing of hepatocyte isolation is important when investigating drug metabolism and toxicity tests in culture.


Asunto(s)
Acetaminofén/toxicidad , Separación Celular , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Ritmo Circadiano , Hepatocitos/efectos de los fármacos , Acetaminofén/administración & dosificación , Animales , Células Cultivadas , Hepatocitos/metabolismo , Inyecciones Intraperitoneales , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Factores de Tiempo
2.
Biochem Biophys Res Commun ; 533(4): 983-987, 2020 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-33008586

RESUMEN

JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy (PML), a demyelinating disease of the central nervous system, in immunocompromised patients. Although PML used to be rare, recently the incidence of PML has risen due to an increase in immunosuppressive therapy. An in vitro JCPyV infection system could be used for anti-drug screening and investigation of tropism changes, but study of JCPyV in vitro has been limited due to the difficulty of efficiently propagating the virus in cultured cells. PML-type JCPyV efficiently propagates in primary human fetal and progenitor cell-derived astrocytes, but the preparation of cells from human fetuses is associated with severe ethical problems. In this study, human iPS cell-derived astrocytes were exposed to PML-type JCPyV. Infection, replication, and VP1 and T antigens of JCPyV were detected and confirmed in this culture. The non-coding control region (NCCR) of M1-IMRb was conserved in infected cells without point mutations. In addition, PML-type JCPyV genomic DNA in infected cells was detected as a single band of approximately 5.1 kbp, with no deletions. This is the first demonstration that human iPS cell-derived astrocytes efficiently support replication of PML-type JCPyV without production of defective interfering particles. These findings indicated that a culture system using human iPS cell-derived astrocyte would be useful for studies of PML, especially for screening anti-JCPyV drugs.


Asunto(s)
Astrocitos/virología , Células Madre Pluripotentes Inducidas/virología , Virus JC/fisiología , Leucoencefalopatía Multifocal Progresiva/virología , Animales , Antígenos Virales/biosíntesis , Antígenos Virales de Tumores/biosíntesis , Astrocitos/patología , Células COS , Proteínas de la Cápside/biosíntesis , Proteínas de la Cápside/inmunología , Diferenciación Celular , Línea Celular , Chlorocebus aethiops , ADN Viral/genética , Genoma Viral , Humanos , Células Madre Pluripotentes Inducidas/patología , Virus JC/genética , Virus JC/patogenicidad , Leucoencefalopatía Multifocal Progresiva/etiología , Leucoencefalopatía Multifocal Progresiva/patología , Células-Madre Neurales/patología , Cultivo de Virus/métodos , Replicación Viral
3.
Biochem Biophys Res Commun ; 522(3): 580-584, 2020 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-31784088

RESUMEN

Since ancient times, Corbicula extract has been believed in Japan to have hepatoprotective effects, but it remains unclear whether these claims are true, and if so, which component is responsible for hepatoprotection. In this study, we showed that Corbicula extract exerted a protective effect against liver damage. Recent work identified acorbine (ß-alanyl-ornithyl-ornithine), a novel tripeptide containing non-proteinogenic amino acids, in the extract of Corbicula japonica. Synthesized acorbine cured alcohol-induced liver damage in mice. In addition, acorbine purified from Corbicula extract exerted a protective effect against alcohol-induced hepatotoxicity in a culture liver model derived from mouse ES/iPS cells. Thus, acorbine is one of the components of Corbicula extract that protects hepatocytes against ethanol-induced death.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/tratamiento farmacológico , Corbicula/química , Péptidos/uso terapéutico , Extractos Vegetales/uso terapéutico , Sustancias Protectoras/uso terapéutico , Consumo de Bebidas Alcohólicas/efectos adversos , Animales , Muerte Celular/efectos de los fármacos , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/patología , Citoprotección/efectos de los fármacos , Etanol/efectos adversos , Femenino , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Ratones Endogámicos C57BL , Péptidos/química , Extractos Vegetales/química , Sustancias Protectoras/química
4.
Arch Microbiol ; 202(1): 105-114, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31485711

RESUMEN

Escherichia coli MazF is a toxin protein that cleaves RNA at ACA sequences. Its activation has been thought to cause growth inhibition, primarily through indiscriminate cleavage of RNA. To investigate responses following MazF activation, transcriptomic profiles of mazF-overexpressing and non-overexpressing E. coli K12 cells were compared. Analyses of differentially expressed genes demonstrated that the presence and the number of ACA trimers in RNA was unrelated to cellular RNA levels. Mapping differentially expressed genes onto the chromosome identified two chromosomal segments in which upregulated genes formed clusters, and these segments were absent in the chromosomes of E. coli strains other than K12. These results suggest that MazF regulates selective, rather than indiscriminate, categories of genes, and is involved in the regulation of horizontally acquired genes. We conclude that the primary role of MazF is not only cleaving RNA indiscriminately but also generating a specific cellular state.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Endorribonucleasas/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica/genética , ARN/genética , Proteínas de Unión al ADN/genética , Endorribonucleasas/genética , Escherichia coli K12/genética , Escherichia coli K12/metabolismo , ARN/química
5.
Xenotransplantation ; 26(1): e12468, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30375053

RESUMEN

The ultimate goal of regenerative medicine is the transplantation of a target organ generated by the patient's own cells. Recently, a method of organ generation using pluripotent stem cells (PSCs) and blastocyst complementation was reported. This approach is based on chimeric animal generation using an early embryo and PSCs, and the contribution of PSCs to the target organ is key to the method's success. However, the contribution rate of PSCs in target organs generated by different chimeric animal generation methods remains unknown. In this study, we used 8-cell embryo aggregation, 8-cell embryo injection, and blastocyst injection to generate interspecies chimeric mice using rat embryonic stem (ES) cells and then investigated the differences in the contribution rate of the rat ES cells. The rate of chimeric mouse generation was the highest using blastocyst injection, followed in order by 8-cell embryo injection and 8-cell embryo aggregation. However, the contribution rate of rat ES cells was the highest in chimeric neonates generated by 8-cell embryo injection, and the difference was statistically significant in the liver. Live functionality was confirmed by analyzing the expression of rat hepatocyte-derived drug-metabolizing enzyme. Collectively, these findings indicate that the 8-cell embryo injection method is the most suitable for generation of PSC-derived organs via chimeric animal generation, particularly for the liver.


Asunto(s)
Blastocisto/citología , Agregación Celular/fisiología , Células Madre Embrionarias/citología , Células Madre Pluripotentes/citología , Trasplante Heterólogo , Animales , Diferenciación Celular/fisiología , Femenino , Ratones , Ratas
6.
Biochem Biophys Res Commun ; 470(4): 917-23, 2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26820538

RESUMEN

The mouse embryonic yolk sac is an extraembryonic membrane that consists of a visceral yolk sac (VYS) and parietal yolk sac (PYS), and functions in hematopoietic-circulation in the fetal stage. The present study was undertaken to examine the normal development of both murine VYS and PYS tissues using various molecular markers, and to establish a novel VYS cell culture system in vitro for analyzing differentiation potentials of VYS cells. RT-PCR and immunohistochemical analyses of gene expression in VYS and PYS tissues during development revealed several useful markers for their identification: HNF1ß, HNF4α, Cdh1 (E-cadherin), Krt8 and Krt18 for VYS epithelial cells, and Stra6, Snail1, Thbd and vimentin for PYS cells. PYS cells exhibited mesenchymal characteristics in gene expression and morphology. When VYS cells at 11.5 days of gestation were cultured in vitro for 7 days, the number of HNF1ß-, HNF4α-, E-cadherin- and cytokeratin-positive VYS epithelial cells was significantly reduced and, instead, Stra6-and vimentin-positive PYS-like cells increased with culture. RT-PCR analyses also demonstrated that gene expression of VYS markers decreased, whereas that of PYS markers increased in the primary culture of VYS cells. These data indicate that VYS epithelial cells rapidly transdifferentiate into PYS cells having mesenchymal characteristics in vitro, which may provide a culture system suitable for studying molecular mechanisms of VYS transdifferentiation into PYS cells and also epithelial-mesenchymal transition.


Asunto(s)
Diferenciación Celular/fisiología , Desarrollo Embrionario/fisiología , Células Madre Mesenquimatosas/citología , Vísceras/citología , Saco Vitelino/citología , Animales , Células Cultivadas , Células Madre Mesenquimatosas/fisiología , Ratones , Ratones Endogámicos C3H , Vísceras/fisiología , Saco Vitelino/fisiología
7.
FEBS Lett ; 598(13): 1633-1643, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38631897

RESUMEN

IFN-γ plays a critical role in host defense against intracellular pathogens. IFN-γ is produced in the bronchoalveolar lavage fluid of mice infected with Pneumocystis, but the role of IFN-γ in host defense against Pneumocystis remains controversial. It has been previously reported that although exogenous IFN-γ has beneficial effects on eradication of Pneumocystis, endogenous IFN-γ has a negative impact on innate immunity in immunocompromised hosts. Surprisingly, CD4+ T cell-depleted IFN-γ deficient (GKO) mice exhibit resistance to Pneumocystis. Alveolar macrophages (AM) from GKO mice exhibit higher expression of macrophage mannose receptor (MMR) and Dectin-1. Concomitantly, they exhibited greater ability to phagocytize Pneumocystis, and this activity was suppressed by inhibitors of these receptors. Incubation with IFN-γ resulted in a reduction in both the expression of these receptors on AM and their Pneumocystis-phagocytic activity. These results indicate that endogenous IFN-γ facilitates Pneumocystis to escape from host innate immunity by attenuating the phagocytic activity of AM via downregulation of MMR and Dectin-1.


Asunto(s)
Linfocitos T CD4-Positivos , Regulación hacia Abajo , Interferón gamma , Lectinas Tipo C , Macrófagos Alveolares , Receptor de Manosa , Fagocitosis , Receptores de Superficie Celular , Animales , Interferón gamma/metabolismo , Interferón gamma/inmunología , Interferón gamma/genética , Lectinas Tipo C/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/inmunología , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/microbiología , Ratones , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/inmunología , Lectinas de Unión a Manosa/metabolismo , Lectinas de Unión a Manosa/genética , Pneumocystis/inmunología , Ratones Endogámicos C57BL , Infecciones por Pneumocystis/inmunología , Infecciones por Pneumocystis/metabolismo , Infecciones por Pneumocystis/microbiología , Infecciones por Pneumocystis/genética , Ratones Noqueados , Depleción Linfocítica , Inmunidad Innata
8.
Transgenic Res ; 22(3): 549-56, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23073907

RESUMEN

The pancreatic islet is an assembly of specific endocrine cells. There are many conflicting reports regarding whether the acinus develops from single or multiple progenitor cells. This study investigated the development and maintenance clonality of the pancreatic acinus and duct using a chimeric analysis with EGFP and DsRed2 transgenic mice. Chimeric mice (G-R mice) were obtained by the aggregation method, using 8-cell stage embryos from EGFP and DsRed2 transgenic mice. The islets from the G-R mice were chimeric and mosaic, consisting of either EGFP- or DsRed2-positive populations, as in previous reports. On the other hand, most acini developed from either EGFP or DsRed2 origin, but some were chimeric. Interestingly, these chimeric acini were clearly separated into two-color regions and were not mosaic. Some large intralobular pancreatic ducts consisting of more than 10 cells were found to be chimeric, but no small ducts made up of less than 9 cells were chimeric. Our histological observations suggest that the pancreatic acinus polyclonally and directionally is maintained by multiple progenitor cells. Pancreatic large ducts also seem to develop polyclonally and might result from the assembly of small ducts that develop from a single origin. These findings provide useful information for further understanding pancreatic maintenance.


Asunto(s)
Proteínas Fluorescentes Verdes/genética , Ratones Transgénicos , Páncreas Exocrino/citología , Páncreas Exocrino/fisiología , Animales , Blastocisto/fisiología , Quimera , Islotes Pancreáticos/citología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Conductos Pancreáticos/citología , Células Madre
9.
Amino Acids ; 45(6): 1343-51, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24081877

RESUMEN

Ammonia, a toxic metabolite, is converted to urea in hepatocytes via the urea cycle, a process necessary for cell/organismal survival. In liver, hepatocytes, polygonal and multipolar structures, have a few sides which face hepatic sinusoids and adjacent hepatocytes to form intercellular bile canaliculi connecting to the ductules. The critical nature of this three-dimensional environment should be related to the maintenance of hepatocyte function such as urea synthesis. Recently, we established an in vitro liver model derived from murine embryonic stem cells, IVL(mES), which included the hepatocyte layer and a surrounding sinusoid vascular-like network. The IVL(mES) culture, where the hepatocyte is polarized in a similar fashion to its in vivo counterpart, could successfully recapitulate in vivo results. L-Ornithine is an intermediate of the urea cycle, but supplemental L-ornithine does not activate the urea cycle in the apolar primary hepatocyte of monolayer culture. In the IVL(mES), supplemental L-ornithine could activate the urea cycle, and also protect against ammonium/alcohol-induced hepatocyte death. While the IVL(mES) displays architectural and functional properties similar to the liver, primary hepatocyte of monolayer culture fail to model critical functional aspects of liver physiology. We propose that the IVL(mES) will represent a useful, humane alternative to animal studies for drug toxicity and mechanistic studies of liver injury.


Asunto(s)
Células Madre Embrionarias/citología , Hígado/citología , Hígado/metabolismo , Ornitina/metabolismo , Urea/metabolismo , Animales , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Animales
10.
J Biol Chem ; 286(33): 28802-28810, 2011 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-21715335

RESUMEN

The complete mechanism of labor induction in eutherian mammals remains unclear. Although important roles for the fetus and placenta in triggering labor have been proposed, no gene has been shown to be required in the fetus/placenta for labor induction. Here we show that Nrk, an X-linked gene encoding a Ser/Thr kinase of the germinal center kinase family, is essential in the fetus/placenta for labor in mice. Nrk was specifically expressed in the spongiotrophoblast layer, a fetus-derived region of the placenta, and Nrk disruption caused dysregulated overgrowth of the layer. Due to preferential inactivation of the paternally derived X chromosome in placenta, Nrk heterozygous mutant placentas exhibited a similar defect to that in Nrk-null tissues when the wild-type allele was paternally derived. However, the phenotype was weaker than in Nrk-null placentas due to leaky Nrk expression from the inactivated X chromosome. Crossing of Nrk-null females to wild-type and Nrk-null males, as well as uterine transfer of Nrk-null fetuses to wild-type females, revealed that pregnant mice exhibit a severe defect in delivery when all fetuses/placentas are Nrk-null. In addition, Nrk was not expressed in female reproductive tissues such as the uterus and ovary, as well as the fetal amnion and yolk sac, in pregnant mice. Progesterone and estrogen levels in the maternal circulation and placenta, which control the timing of labor, were unaffected upon Nrk disruption. We thus provide evidence for a novel labor-inducing fetoplacental signal that depends on the X chromosome and possibly arises from the placenta.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/metabolismo , Trabajo de Parto/metabolismo , Placenta/metabolismo , Proteínas Gestacionales/metabolismo , Preñez/metabolismo , Embarazo/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Alelos , Animales , Cruzamientos Genéticos , Femenino , Péptidos y Proteínas de Señalización Intracelular/genética , Trabajo de Parto/genética , Masculino , Ratones , Ratones Mutantes , Circulación Placentaria/fisiología , Embarazo/genética , Proteínas Gestacionales/genética , Preñez/genética , Proteínas Serina-Treonina Quinasas/genética , Transducción de Señal/fisiología , Cromosoma X/genética , Cromosoma X/metabolismo
11.
Drug Metab Dispos ; 40(1): 169-77, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22010217

RESUMEN

Primary hepatocytes have been used in drug development for the evaluation of hepatotoxicity of candidate compounds. However, the rapid depression of their hepatic characters in vitro must be improved to predict toxicity with higher accuracy. We have hypothesized that a well organized tissue construct that includes nonparenchymal cells and appropriate scaffold material(s) could overcome this difficulty by remediating the viability and physiological function of primary hepatocytes. In this study, we constructed an in vitro liver tissue model, consisting of mouse primary hepatocytes assembling around an endothelial cell network on Engelbreth-Holm-Swarm gel, and examined its response to acetaminophen treatment. The increase in lactate dehydrogenase release after the exposure to acetaminophen was induced earlier in the liver tissue model than in monolayer hepatocytes alone, suggesting that the tissue model was more sensitive to an acetaminophen-induced toxicity. On the basis of our results, we conclude that liver tissue models of this kind may enhance the responses of hepatocytes against xenobiotics via the maintenance of hepatic genes and functions such as cytochrome P450s. These findings will contribute to the development of more accurate systems for evaluating hepatotoxicity.


Asunto(s)
Acetaminofén/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas , Células Endoteliales/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Células Endoteliales/metabolismo , Hepatocitos/metabolismo , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos
12.
World J Gastroenterol ; 28(14): 1444-1454, 2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35582675

RESUMEN

BACKGROUND: Liver transplantation is a therapy for irreversible liver failure; however, at present, donor organs are in short supply. Cell transplantation therapy for liver failure is still at the developmental stage and is critically limited by a shortage of human primary hepatocytes. AIM: To investigate the possibility that hepatic progenitor cells (HPCs) prepared from the portal branch-ligated hepatic lobe may be used in regenerative medicine, we attempted to enable the implantation of extracellular matrices containing organoids consisting of HPC-derived hepatocytes and non-parenchymal cells. METHODS: In vitro liver organoid tissue has been generated by accumulating collagen fibrils, fibroblasts, and HPCs on a mesh of polylactic acid fabric using a bioreactor; this was subsequently implanted into syngeneic wild-type mice. RESULTS: The in vitro liver organoid tissues generated transplantable tissues in the condensed collagen fibril matrix and were obtained from the mouse through partial hepatectomy. CONCLUSION: Liver organoid tissue was produced from expanded HPCs using an originally designed bioreactor system. This tissue was comparable to liver lobules, and with fibroblasts embedded in the network collagen fibrils of this artificial tissue, it is useful for reconstructing the hepatic interstitial structure.


Asunto(s)
Matriz Extracelular , Fallo Hepático , Animales , Colágeno/análisis , Hepatocitos , Humanos , Hígado/cirugía , Ratones , Células Madre
13.
Life Sci Alliance ; 5(5)2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35181633

RESUMEN

The processing of type I procollagen is essential for fibril formation; however, the steps involved remain controversial. We constructed a live cell imaging system by inserting fluorescent proteins into type I pre-procollagen α1. Based on live imaging and immunostaining, the C-propeptide is intracellularly cleaved at the perinuclear region, including the endoplasmic reticulum, and subsequently accumulates at the upside of the cell. The N-propeptide is also intracellularly cleaved, but is transported with the repeating structure domain of collagen into the extracellular region. This system makes it possible to detect relative increases and decreases in collagen secretion in a high-throughput manner by assaying fluorescence in the culture medium, and revealed that the rate-limiting step for collagen secretion occurs after the synthesis of procollagen. In the present study, we identified a defect in procollagen processing in activated hepatic stellate cells, which secrete aberrant collagen fibrils. The results obtained demonstrated the intracellular processing of type I procollagen, and revealed a link between dysfunctional processing and diseases such as hepatic fibrosis.


Asunto(s)
Colágeno , Procolágeno , Colágeno/metabolismo , Retículo Endoplásmico/metabolismo , Procolágeno/metabolismo
14.
J Oral Biosci ; 64(2): 237-244, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35398598

RESUMEN

OBJECTIVES: Osteoclasts can sense the surface topography of materials. However, it is difficult to identify the structural factors that affect osteoclast formation and its function. Furthermore, we hypothesized that the type of osteoclast precursor cells also affects osteoclastogenesis in the materials. In this study, we investigated the effects of defined micro/nanoscale patterns on osteoclastogenesis from bone marrow cells (BMCs). METHODS: Various cyclo-olefin polymer (COP) patterns were prepared using nanoimprinting. The effects of shape, size, and height of the patterns, and the wettability of the patterned surfaces on osteoclastogenesis from BMCs were evaluated in vitro. RESULTS: Osteoclast formation was promoted on pillars (diameter, 1 µm or 500 nm; height, 500 nm). Notably, osteoclastogenesis from BMCs was better promoted on hydrophobic pillars than on hydrophilic pillars. In contrast, decreased osteoclast formation was observed on the nanopillars (diameter, 100 nm; height, 200 nm). CONCLUSIONS: We demonstrated the promotion of osteoclast formation from BMCs on hydrophobic pillars with diameters of 1 µm and 500 nm. Some cellular behaviors in the patterns were dependent on the type of osteoclast precursor cells. The designed patterns are useful for designing the surface of dental implants or bone replacement materials with a controllable balance between osteoblast and osteoclast activities.


Asunto(s)
Osteoclastos , Ligando RANK , Animales , Células de la Médula Ósea , Ratones , Osteoblastos , Osteogénesis , Ligando RANK/farmacología
15.
Tissue Eng Part A ; 27(17-18): 1160-1167, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33267675

RESUMEN

Drug-induced liver toxicity remains a major cause of drug withdrawal from animal testing and human clinical trials. A functional liver culture model corresponding to the liver is urgently required; however, in previous liver models, it has proven difficult to stably maintain multiple liver functions. Previously reported fluid-based systems have some advantages for hepatocyte culture, but have insufficient liver-specific functions because they simply involve moving conventional hepatocyte cultures from a dish into a fluid-based system. Importantly, these cultures have no liver tissue-specific structures that construct liver-specific cellular polarities, such as apical, basolateral, and basal faces. In this study, we developed a fluid-based system for our liver tissue culture models. The liver tissues that were constructed in our originally designed fluid-based systems represent a tissue culture model for studying hepatic functions. Together, our findings show that by mimicking the structure of the liver in the body, our system effectively maintains multiple liver-specific functions. Impact statement A functional liver culture model corresponding to the liver is urgently required; however, in previous liver models, it has proven difficult to stably maintain multiple liver functions. In this study, we developed a fluid-based system for our liver tissue culture models. The liver tissues that were constructed in our originally designed fluid-based systems represent a tissue culture model for studying hepatic functions. Together, our findings show that by mimicking the structure of the liver in the body, our system effectively maintains multiple liver-specific functions.


Asunto(s)
Hepatocitos , Preparaciones Farmacéuticas , Animales , Polaridad Celular , Endotelio , Humanos , Hígado
16.
Front Cell Dev Biol ; 9: 667304, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34368123

RESUMEN

Dendritic cells (DC) are professional antigen-presenting cells that develop from hematopoietic stem cells. Different DC subsets exist based on ontogeny, location and function, including the recently identified proinflammatory DC3 subset. DC3 have the prominent activity to polarize CD8+ T cells into CD8+ CD103+ tissue resident T cells. Here we describe human DC3 differentiated from induced pluripotent stem cells (iPS cells). iPS cell-derived DC3 have the gene expression and surface marker make-up of blood DC3 and polarize CD8+ T cells into CD8+ CD103+ tissue-resident memory T cells in vitro. To test the impact of malignant JAK2 V617F mutation on DC3, we differentiated patient-specific iPS cells with JAK2 V617Fhet and JAK2 V617Fhom mutations into JAK2 V617Fhet and JAK2 V617Fhom DC3. The JAK2 V617F mutation enhanced DC3 production and caused a bias toward erythrocytes and megakaryocytes. The patient-specific iPS cell-derived DC3 are expected to allow studying DC3 in human diseases and developing novel therapeutics.

17.
Biochem Biophys Res Commun ; 403(3-4): 298-304, 2010 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-21075076

RESUMEN

Hepatic stem/progenitor cells are one of several cell sources that show promise for restoration of liver mass and function. Although hepatic progenitor cells (HPCs), including oval cells, are induced by administration of certain hepatotoxins in experimental animals, such a strategy would be inappropriate in a clinical setting. Here, we investigated the possibility of isolating HPCs in a portal branch-ligated liver model without administration of any chemical agents. A non-parenchymal cell fraction was prepared from the portal branch-ligated or non-ligated lobe, and seeded onto plates coated with laminin. Most of the cells died, but a small number were able to proliferate. These proliferating cells were cloned as portal branch ligation-stimulated hepatic cells (PBLHCs) by the limiting dilution method. The PBLHCs expressed cytokeratin19, albumin, and Hmga2. The PBLHCs exhibited metabolic functions such as detoxification of ammonium ions and synthesis of urea on Matrigel-coated plates in the presence of oncostatin M. In Matrigel mixed with type I collagen, the PBLHCs became rearranged into cystic and tubular structures. Immunohistochemical staining demonstrated the presence of Hmga2-positive cells around the interlobular bile ducts in the portal branch-ligated liver lobes. In conclusion, successful isolation of bipotent hepatic progenitor cell clones, PBLHCs, from the portal branch-ligated liver lobes of mice provides the possibility of future clinical application of portal vein ligation to induce hepatic progenitor cells.


Asunto(s)
Separación Celular/métodos , Hepatocitos/citología , Regeneración Hepática , Células Madre/citología , Animales , Conductos Biliares/crecimiento & desarrollo , Proliferación Celular , Células Cultivadas , Proteína HMGA2/análisis , Proteína HMGA2/biosíntesis , Ratones , Ratones Endogámicos C57BL , Morfogénesis , Células Madre/química
18.
Biochem Biophys Res Commun ; 385(1): 123-8, 2009 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-19422803

RESUMEN

The pancreas and the liver share the same endodermal origin. We have been studying whether mature hepatocytes can be induced to differentiate into pancreatic beta-cells by in vitro delivery of transcriptional factors using a non-viral approach. Here we showed that nucleofection allowed suitable transfection of primary hepatocytes employing various non-viral methods. We introduced either pancreatic and duodenal homeobox 1 (Pdx1) or neurogenin 3 (Ngn3), or both, into the mature cells using nucleofection. Co-expression of pdx1 and ngn3 using a bicistronic vector activated the transcription of various islet-related genes, and the transfected hepatocytes acquired the ability to synthesize and secrete insulin. Our results suggest that simultaneous expression of Pdx1 and Ngn3 is an excellent inducer of liver-to-pancreas reprogramming, and that reprogramming will occur even in mature somatic cells without the need for viral vectors. These findings are of considerable significance for further therapeutic development for various intractable diseases including diabetes.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Diferenciación Celular/genética , Hepatocitos/fisiología , Proteínas de Homeodominio/biosíntesis , Células Secretoras de Insulina/citología , Insulina/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Transactivadores/biosíntesis , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Vectores Genéticos , Hepatocitos/citología , Hepatocitos/metabolismo , Proteínas de Homeodominio/genética , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Ratones , Proteínas del Tejido Nervioso/genética , Transactivadores/genética , Transfección
19.
Cardiovasc Res ; 80(2): 175-80, 2008 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18791204

RESUMEN

AIMS: Neointimal formation after percutaneous coronary intervention (PCI), termed restenosis, limits therapeutic revascularization. Since it is now known that vascular injury involves an inflammatory response, we examined the role of tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in the neointimal formation after injury. METHODS AND RESULTS: Control (BALB/c), TNF-alpha-deficient (Tnf(-/-)), IFN-gamma-deficient (Ifng(-/-)), or double-deficient (Tnf(-/-)Ifng(-/-)) mice were subjected to wire-mediated vascular injury of the right femoral artery. Neointimal formation after injury was significantly reduced after the injury in the Tnf(-/-)Ifng(-/-) mice, compared to that in the control, Tnf(-/-), and Ifng(-/-) mice. Immunohistochemical analysis showed that TNF-alpha and IFN-gamma were expressed in neointimal lesions in the control mice, but not in mice with deficiency of the corresponding cytokine. No significant difference in re-endothelialization was observed among these groups. The number of proliferating cell nuclear antigen in the neointimal lesions was significantly decreased in the Tnf(-/-)Ifng(-/-) mice. Bone marrow transplantation experiments revealed that deficiency of TNF-alpha and IFN-gamma specifically in bone marrow cells significantly inhibited neointimal formation after vascular injury. CONCLUSION: The absence of TNF-alpha and IFN-gamma in bone marrow cells synergistically inhibits neointimal formation following vascular injury, and thus, may provide new insights into the mechanisms underlying restenosis after PCI.


Asunto(s)
Arteriopatías Oclusivas/prevención & control , Células de la Médula Ósea/inmunología , Trasplante de Médula Ósea , Proliferación Celular , Arteria Femoral/patología , Interferón gamma/deficiencia , Factor de Necrosis Tumoral alfa/deficiencia , Túnica Íntima/patología , Animales , Arteriopatías Oclusivas/inmunología , Arteriopatías Oclusivas/patología , Constricción Patológica , Modelos Animales de Enfermedad , Células Endoteliales/patología , Arteria Femoral/inmunología , Arteria Femoral/lesiones , Interferón gamma/genética , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Miocitos del Músculo Liso/patología , Factor de Necrosis Tumoral alfa/genética , Túnica Íntima/inmunología , Túnica Íntima/lesiones
20.
J Biosci Bioeng ; 125(3): 353-358, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29146529

RESUMEN

Exposure to UV radiation to human skin up-regulates the synthesis of matrix metalloproteinase (MMP) family. Gelatinases are member of MMPs which have been suggested to play an important role in photoaging such as wrinkle formation. To inhibit gelatinase activity is regarded to be very important to keep healthy skin and to protect wrinkle formation. On the other hand, anti-photoaging agents are expected to be derived from natural resources, especially plants. Plant extracts having gelatinase-inhibitory effect that might be used as safe anti-photoaging ingredient were widely screened. An extract of rhizomes of Curcuma longa L. showed inhibitory effect of gelatinase activity. Curcuminoids and slight amount of compound, 6,11-dihydroxy-3-(4-hydroxy-3-mthoxyphenethyl)-7-[(E)-4-(4-hydroxy-3-methoxyphenyl)-2-oxo-3-butenyl]-10-methoxy-2-oxabicyclo[6.3.1.]dodeca-1(11),8(12),9-trien-5-yl (E)-3-(4-hydroxy-3-methoxyphenyl)-2-propenoate (curcuminoid D) were isolated as the gelatinase-inhibitory components from methanol extract of rhizomes. The structure of curcuminoid D was determined by means of spectral data including 1H- and 13C-NMR, and IR. Curcumin exerted the enhancing effect on deposition of basement membrane component at dermal-epidermal junction in skin equivalent model. Topical application of cream containing turmeric extract significantly improved facial skin elasticity and decreased the number of gelatinase-positive stratum corneum clusters in human facial skins. These results indicated that turmeric is an effective ingredient to improve skin condition and to prevent skin from photoaging by suppressing activation of gelatinase chronically caused by UV.


Asunto(s)
Curcuma/química , Gelatinasas/antagonistas & inhibidores , Extractos Vegetales/farmacología , Rizoma/química , Piel/efectos de los fármacos , Células Cultivadas , Curcumina/farmacología , Humanos , Recién Nacido , Queratinocitos/efectos de los fármacos , Queratinocitos/fisiología , Masculino , Metanol/farmacología , Sustancias Protectoras/farmacología , Piel/efectos de la radiación , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , Rayos Ultravioleta/efectos adversos
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