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Sample records for primary human hepatocyte

  1. 3D Cultivation Techniques for Primary Human Hepatocytes

    PubMed Central

    Bachmann, Anastasia; Moll, Matthias; Gottwald, Eric; Nies, Cordula; Zantl, Roman; Wagner, Helga; Burkhardt, Britta; Sánchez, Juan J. Martínez; Ladurner, Ruth; Thasler, Wolfgang; Damm, Georg; Nussler, Andreas K.

    2015-01-01

    One of the main challenges in drug development is the prediction of in vivo toxicity based on in vitro data. The standard cultivation system for primary human hepatocytes is based on monolayer cultures, even if it is known that these conditions result in a loss of hepatocyte morphology and of liver-specific functions, such as drug-metabolizing enzymes and transporters. As it has been demonstrated that hepatocytes embedded between two sheets of collagen maintain their function, various hydrogels and scaffolds for the 3D cultivation of hepatocytes have been developed. To further improve or maintain hepatic functions, 3D cultivation has been combined with perfusion. In this manuscript, we discuss the benefits and drawbacks of different 3D microfluidic devices. For most systems that are currently available, the main issues are the requirement of large cell numbers, the low throughput, and expensive equipment, which render these devices unattractive for research and the drug-developing industry. A higher acceptance of these devices could be achieved by their simplification and their compatibility with high-throughput, as both aspects are of major importance for a user-friendly device.

  2. Helicobacter hepaticus Induces an Inflammatory Response in Primary Human Hepatocytes

    PubMed Central

    Kleine, Moritz; Worbs, Tim; Schrem, Harald; Vondran, Florian W. R.; Kaltenborn, Alexander; Klempnauer, Jürgen; Förster, Reinhold; Josenhans, Christine; Suerbaum, Sebastian; Bektas, Hüseyin

    2014-01-01

    Helicobacter hepaticus can lead to chronic hepatitis and hepatocellular carcinoma in certain strains of mice. Until now the pathogenic role of Helicobacter species on human liver tissue is still not clarified though Helicobacter species identification in human liver cancer was successful in case controlled studies. Therefore we established an in vitro model to investigate the interaction of primary human hepatocytes (PHH) with Helicobacter hepaticus. Successful co-culturing of PHH with Helicobacter hepaticus was confirmed by visualization of motile bacteria by two-photon-microscopy. Isolated human monocytes were stimulated with PHH conditioned media. Changes in mRNA expression of acute phase cytokines and proteins in PHH and stimulated monocytes were determined by Real-time PCR. Furthermore, cytokines and proteins were analyzed in PHH culture supernatants by ELISA. Co-cultivation with Helicobacter hepaticus induced mRNA expression of Interleukin-1 beta (IL-1β), Tumor necrosis factor-alpha, Interleukin-8 (IL-8) and Monocyte chemotactic protein-1 (MCP-1) in PHH (p<0.05) resulting in a corresponding increase of IL-8 and MCP-1 concentrations in PHH supernatants (p<0.05). IL-8 and IL-1β mRNA expression was induced in monocytes stimulated with Helicobacter hepaticus infected PHH conditioned media (p<0.05). An increase of Cyclooxygenase-2 mRNA expression was observed, with a concomitant increase of prostaglandin E2 concentration in PHH supernatants at 24 and 48 h (p<0.05). In contrast, at day 7 of co-culture, no persistent elevation of cytokine mRNA could be detected. High expression of intercellular adhesion molecule-1 on PHH cell membranes after co-culture was shown by two-photon-microscopy and confirmed by flow-cytomety. Finally, expression of Cytochrome P450 3A4 and albumin mRNA were downregulated, indicating an impairment of hepatocyte synthesis function by Helicobacter hepaticus presence. This is the first in vitro model demonstrating a pathogenic effect of a

  3. Bile acid-induced necrosis in primary human hepatocytes and in patients with obstructive cholestasis

    SciTech Connect

    Woolbright, Benjamin L.; Dorko, Kenneth; Antoine, Daniel J.; Clarke, Joanna I.; Gholami, Parviz; Li, Feng; Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson; Fan, Fang; Jenkins, Rosalind E.; Park, B. Kevin; Hagenbuch, Bruno; Olyaee, Mojtaba; Jaeschke, Hartmut

    2015-03-15

    Accumulation of bile acids is a major mediator of cholestatic liver injury. Recent studies indicate bile acid composition between humans and rodents is dramatically different, as humans have a higher percent of glycine conjugated bile acids and increased chenodeoxycholate content, which increases the hydrophobicity index of bile acids. This increase may lead to direct toxicity that kills hepatocytes, and promotes inflammation. To address this issue, this study assessed how pathophysiological concentrations of bile acids measured in cholestatic patients affected primary human hepatocytes. Individual bile acid levels were determined in serum and bile by UPLC/QTOFMS in patients with extrahepatic cholestasis with, or without, concurrent increases in serum transaminases. Bile acid levels increased in serum of patients with liver injury, while biliary levels decreased, implicating infarction of the biliary tracts. To assess bile acid-induced toxicity in man, primary human hepatocytes were treated with relevant concentrations, derived from patient data, of the model bile acid glycochenodeoxycholic acid (GCDC). Treatment with GCDC resulted in necrosis with no increase in apoptotic parameters. This was recapitulated by treatment with biliary bile acid concentrations, but not serum concentrations. Marked elevations in serum full-length cytokeratin-18, high mobility group box 1 protein (HMGB1), and acetylated HMGB1 confirmed inflammatory necrosis in injured patients; only modest elevations in caspase-cleaved cytokeratin-18 were observed. These data suggest human hepatocytes are more resistant to human-relevant bile acids than rodent hepatocytes, and die through necrosis when exposed to bile acids. These mechanisms of cholestasis in humans are fundamentally different to mechanisms observed in rodent models. - Highlights: • Cholestatic liver injury is due to cytoplasmic bile acid accumulation in hepatocytes. • Primary human hepatocytes are resistant to BA-induced injury

  4. Micropatterned coculture of primary human hepatocytes and supportive cells for the study of hepatotropic pathogens.

    PubMed

    March, Sandra; Ramanan, Vyas; Trehan, Kartik; Ng, Shengyong; Galstian, Ani; Gural, Nil; Scull, Margaret A; Shlomai, Amir; Mota, Maria M; Fleming, Heather E; Khetani, Salman R; Rice, Charles M; Bhatia, Sangeeta N

    2015-12-01

    The development of therapies and vaccines for human hepatropic pathogens requires robust model systems that enable the study of host-pathogen interactions. However, in vitro liver models of infection typically use either hepatoma cell lines that exhibit aberrant physiology or primary human hepatocytes in culture conditions in which they rapidly lose their hepatic phenotype. To achieve stable and robust in vitro primary human hepatocyte models, we developed micropatterned cocultures (MPCCs), which consist of primary human hepatocytes organized into 2D islands that are surrounded by supportive fibroblast cells. By using this system, which can be established over a period of days, and maintained over multiple weeks, we demonstrate how to recapitulate in vitro hepatic life cycles for the hepatitis B and C viruses and the Plasmodium pathogens P. falciparum and P. vivax. The MPCC platform can be used to uncover aspects of host-pathogen interactions, and it has the potential to be used for drug and vaccine development. PMID:26584444

  5. Maintenance of Hepatic Functions in Primary Human Hepatocytes Cultured on Xeno-Free and Chemical Defined Human Recombinant Laminins.

    PubMed

    Watanabe, Masaaki; Zemack, Helen; Johansson, Helene; Hagbard, Louise; Jorns, Carl; Li, Meng; Ellis, Ewa

    2016-01-01

    Refined methods for maintaining specific functions of isolated hepatocytes under xeno-free and chemical defined conditions is of great importance for the development of hepatocyte research and regenerative therapy. Laminins, a large family of heterotrimeric basement membrane adhesion proteins, are highly cell and tissue type specific components of the extracellular matrix and strongly influence the behavior and function of associated cells and/or tissues. However, detailed biological functions of many laminin isoforms are still to be evaluated. In this study, we determined the distribution of laminin isoforms in human liver tissue and isolated primary human hepatocytes by western blot analysis, and investigated the efficacy of different human recombinant laminin isoforms on hepatic functions during culture. Protein expressions of laminin-chain α2, α3, α4, β1, β3, γ1, and γ2 were detected in both isolated human hepatocytes and liver tissue. No α1 and α5 expression could be detected in liver tissue or hepatocytes. Hepatocytes were isolated from five different individual livers, and cultured on human recombinant laminin isoforms -111, -211, -221, -332, -411, -421, -511, and -521 (Biolamina AB), matrigel (extracted from Engelbreth-Holm-Swarm sarcoma), or collagen type IV (Collagen). Hepatocytes cultured on laminin showed characteristic hexagonal shape in a flat cell monolayer. Viability, double stranded DNA concentration, and Ki67 expression for hepatocytes cultured for six days on laminin were comparable to those cultured on EHS and Collagen. Hepatocytes cultured on laminin also displayed production of human albumin, alpha-1-antitrypsin, bile acids, and gene expression of liver-enriched factors, such as hepatocyte nuclear factor 4 alpha, glucose-6-phosphate, cytochrome P450 3A4, and multidrug resistance-associated protein 2. We conclude that all forms of human recombinant laminin tested maintain cell viability and liver-specific functions of primary human

  6. Hypoxia promotes liver-stage malaria infection in primary human hepatocytes in vitro.

    PubMed

    Ng, Shengyong; March, Sandra; Galstian, Ani; Hanson, Kirsten; Carvalho, Tânia; Mota, Maria M; Bhatia, Sangeeta N

    2014-02-01

    Homeostasis of mammalian cell function strictly depends on balancing oxygen exposure to maintain energy metabolism without producing excessive reactive oxygen species. In vivo, cells in different tissues are exposed to a wide range of oxygen concentrations, and yet in vitro models almost exclusively expose cultured cells to higher, atmospheric oxygen levels. Existing models of liver-stage malaria that utilize primary human hepatocytes typically exhibit low in vitro infection efficiencies, possibly due to missing microenvironmental support signals. One cue that could influence the infection capacity of cultured human hepatocytes is the dissolved oxygen concentration. We developed a microscale human liver platform comprised of precisely patterned primary human hepatocytes and nonparenchymal cells to model liver-stage malaria, but the oxygen concentrations are typically higher in the in vitro liver platform than anywhere along the hepatic sinusoid. Indeed, we observed that liver-stage Plasmodium parasite development in vivo correlates with hepatic sinusoidal oxygen gradients. Therefore, we hypothesized that in vitro liver-stage malaria infection efficiencies might improve under hypoxia. Using the infection of micropatterned co-cultures with Plasmodium berghei, Plasmodium yoelii or Plasmodium falciparum as a model, we observed that ambient hypoxia resulted in increased survival of exo-erythrocytic forms (EEFs) in hepatocytes and improved parasite development in a subset of surviving EEFs, based on EEF size. Further, the effective cell surface oxygen tensions (pO2) experienced by the hepatocytes, as predicted by a mathematical model, were systematically perturbed by varying culture parameters such as hepatocyte density and height of the medium, uncovering an optimal cell surface pO2 to maximize the number of mature EEFs. Initial mechanistic experiments revealed that treatment of primary human hepatocytes with the hypoxia mimetic, cobalt(II) chloride, as well as a HIF-1

  7. Primary human hepatocytes versus hepatic cell line: assessing their suitability for in vitro nanotoxicology.

    PubMed

    Kermanizadeh, Ali; Gaiser, Birgit K; Ward, Michael B; Stone, Vicki

    2013-11-01

    The use of hepatocyte cell lines as a replacement for animal models have been heavily criticised mainly due to low expression of metabolism enzymes. This study compares primary human hepatocytes with the C3A cell line and with respect to their response to a panel of nanomaterials (NMs; two ZnO, two MWCNTs, one Ag and one positively functionalised TiO₂). The cell line was very comparable with the primary hepatocytes with regards to their cytotoxic response to the NMs (Ag > uncoated ZnO > coated ZnO). The LC₅₀ was not attained in the presence of the MWCNTs and the TiO₂ NMs. All NMs significantly increased IL-8 production, with no change in levels of TNF-α and IL-6. Albumin production was measured as an indicator of hepatic function. The authors found no change in levels of albumin with the exception of the coated ZnO NM at the LC₅₀ concentration. NM uptake was similar for both the primary hepatocytes and C3A cells as investigated by TEM. Meanwhile, the authors confirmed greater levels of CYP450 activity in untreated primary cells. This study demonstrates that the C3A cell line is a good model for investigating NM-induced hepatocyte responses with respect to uptake, cytotoxicity, pro-inflammatory cytokine production and albumin production. PMID:23009365

  8. Genotoxic effects of alpha-hexachlorocyclohexane in primary cultures of rodent and human hepatocytes.

    PubMed

    Mattioli, F; Robbiano, L; Adamo, D; Federa, R; Martelli, A; Brambilla, G

    1996-01-01

    The genotoxicity of alpha-hexachlorocyclohexane (alpha-HCH) was evaluated in primary cultures of mouse, rat and human hepatocytes. DNA fragmentation was measured by the alkaline elution technique and DNA repair synthesis by quantitative autoradiography. A 20 h exposure to subtoxic concentrations ranging from 0.056 to 0.32 mM produced a dose-dependent frequency of DNA breaks in rat hepatocytes and in hepatocytes from four of five human donors, but not in mouse hepatocytes, DNA repair induction was absent in hepatocytes from all three species. The reduction in the frequency of DNA breaks observed in rat hepatocytes simultaneously exposed to metyrapone suggests that alpha-HCH is transformed into reactive species by a cytochrome P450-dependent reaction. The detection of DNA fragmentation but not of DNA repair synthesis may be tentatively explained by assuming that alpha-HCH behaves as a chemical eliciting short patch DNA repair, which is more easily revealed as genotoxic by the occurrence of DNA single-strand breaks. PMID:8671720

  9. Cytotoxicity evaluation using cryopreserved primary human hepatocytes in various culture formats.

    PubMed

    Richert, Lysiane; Baze, Audrey; Parmentier, Céline; Gerets, Helga H J; Sison-Young, Rowena; Dorau, Martina; Lovatt, Cerys; Czich, Andreas; Goldring, Christopher; Park, B Kevin; Juhila, Satu; Foster, Alison J; Williams, Dominic P

    2016-09-01

    Sixteen training compounds selected in the IMI MIP-DILI consortium, 12 drug-induced liver injury (DILI) positive compounds and 4 non-DILI compounds, were assessed in cryopreserved primary human hepatocytes. When a ten-fold safety margin threshold was applied, the non-DILI-compounds were correctly identified 2h following a single exposure to pooled human hepatocytes (n=13 donors) in suspension and 14-days following repeat dose exposure (3 treatments) to an established 3D-microtissue co-culture (3D-MT co-culture, n=1 donor) consisting of human hepatocytes co-cultured with non-parenchymal cells (NPC). In contrast, only 5/12 DILI-compounds were correctly identified 2h following a single exposure to pooled human hepatocytes in suspension. Exposure of the 2D-sandwich culture human hepatocyte monocultures (2D-sw) for 3days resulted in the correct identification of 11/12 DILI-positive compounds, whereas exposure of the human 3D-MT co-cultures for 14days resulted in identification of 9/12 DILI-compounds; in addition to ximelagatran (also not identified by 2D-sw monocultures, Sison-Young et al., 2016), the 3D-MT co-cultures failed to detect amiodarone and bosentan. The sensitivity of the 2D human hepatocytes co-cultured with NPC to ximelagatran was increased in the presence of lipopolysaccharide (LPS), but only at high concentrations, therefore preventing its classification as a DILI positive compound. In conclusion (1) despite suspension human hepatocytes having the greatest metabolic capacity in the short term, they are the least predictive of clinical DILI across the MIP-DILI test compounds, (2) longer exposure periods than 72h of human hepatocytes do not allow to increase DILI-prediction rate, (3) co-cultures of human hepatocytes with NPC, in the presence of LPS during the 72h exposure period allow the assessment of innate immune system involvement of a given drug. PMID:27363785

  10. IFNL3 genotype is associated with differential induction of IFNL3 in primary human hepatocytes

    PubMed Central

    Kurbanov, Fuat; Kim, Yonghak; Latanich, Rachel; Chaudhari, Pooja; El-Diwany, Ramy; Knabel, Matt; Kandathil, Abraham J; Cameron, Andrew; Cox, Andrea; Jang, Yoon-Young; Thomas, David L; Balagopal, Ashwin

    2016-01-01

    Background Lambda interferons (IFNLs) have potent antiviral activity against HCV, and polymorphisms within the IFNL gene cluster near the IFNL3 gene strongly predict spontaneous- and treatment-related HCV infection outcomes. The mechanism(s) linking IFNL polymorphisms and HCV control is currently elusive. Methods IFNL induction was studied in primary human hepatocytes (PHH) from 18 human donors, peripheral blood mononuclear cells (PBMCs) from 18 human donors, multiple cell lines and induced pluripotent stem cell-derived hepatocyte-like cells (iPSC-hepatocytes) from 7 human donors. After stimulation with intracellular RNA and infectious HCV, quantitative PCR (qPCR) primers and probes were designed to distinguish and quantify closely related IFNL messenger (m)RNAs from IFNL1, IFNL2 and IFNL3. Results PHH demonstrated the most potent induction of IFNLs, although had lower pre-stimulation levels compared to PBMCs, monocytes and cell lines. PHH stimulation with cytoplasmic poly I:C induced >1,000-fold expression of IFNL1, IFNL2 and IFNL3. PHH from donors who were homozygous for the favourable IFNL3 allele (IFNL3-CC) had higher IFNL3 induction compared to PHH from IFNL3-TT donors (P=0.03). Baseline IFNL mRNA expression and induction was also tested in iPSC-hepatocytes: iPSC-hepatocytes had significantly higher baseline expression of IFNLs compared to PHH (P<0.0001), and IFNL3 induction was marginally different in iPSC-hepatocytes by IFNL genotype (P=0.07). Conclusions Hepatocytes express IFNLs when stimulated by a synthetic viral RNA that signals the cell through the cytoplasm. IFNL induction may be greater in persons with the favourable IFNL3 allele. These data provide insight into the strong linkage between IFNL3 genetics and control of HCV infection. PMID:26109548

  11. Bile Acid-Induced Necrosis in Primary Human Hepatocytes and in Patients with Obstructive Cholestasis

    PubMed Central

    Woolbright, Benjamin L.; Dorko, Kenneth; Antoine, Daniel J.; Clarke, Joanna I.; Gholami, Parviz; Li, Feng; Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson; Fan, Fang; Jenkins, Rosalind E.; Park, B. Kevin; Hagenbuch, Bruno; Olyaee, Mojtaba; Jaeschke, Hartmut

    2015-01-01

    Accumulation of bile acids is a major mediator of cholestatic liver injury. Recent studies indicate bile acid composition between humans and rodents is dramatically different, as humans have a higher percent of glycine conjugated bile acids and increased chenodeoxycholate content, which increases the hydrophobicity index of bile acids. This increase may lead to direct toxicity that kills hepatocytes, and promotes inflammation. To address this issue, this study assessed how pathophysiological concentrations of bile acids measured in cholestatic patients affected primary human hepatocytes. Individual bile acid levels were determined in serum and bile by UPLC/QTOFMS in patients with extrahepatic cholestasis with, or without, concurrent increases in serum transaminases. Bile acid levels increased in serum of patients with liver injury, while biliary levels decreased, implicating infarction of the biliary tracts. To assess bile acid-induced toxicity in man, primary human hepatocytes were treated with relevant concentrations, derived from patient data, of the model bile acid glycochenodeoxycholic acid (GCDC). Treatment with GCDC resulted in necrosis with no increase in apoptotic parameters. This was recapitulated by treatment with biliary bile acid concentrations, but not serum concentrations. Marked elevations in serum full-length cytokeratin-18, high mobility group box1 protein (HMGB1), and acetylated HMGB1 confirmed inflammatory necrosis in injured patients; only modest elevations in caspase-cleaved cytokeratin-18 were observed. These data suggest human hepatocytes are more resistant to human-relevant bile acids than rodent hepatocytes, and die through necrosis when exposed to bile acids. These mechanisms of cholestasis in humans are fundamentally different to mechanisms observed in rodent models. PMID:25636263

  12. Xenobiotic-Metabolizing Enzyme and Transporter Gene Expression in Primary Cultures of Human Hepatocytes Modulated by Toxcast Chemicals

    EPA Science Inventory

    Primary human hepatocyte cultures are useful in vitro model systems of human liver because when cultured under appropriate conditions the hepatocytes retain liver-like functionality such as metabolism, transport, and cell signaling. This model system was used to characterize the ...

  13. Biotransformation of deramciclane in primary hepatocytes of rat, mouse, rabbit, dog, and human.

    PubMed

    Monostory, Katalin; Kohalmy, Krisztina; Ludányi, Krisztina; Czira, Gábor; Holly, Sándor; Vereczkey, László; Urmös, Iván; Klebovich, Imre; Kóbori, László

    2005-11-01

    The metabolic fate of deramciclane [(1R,2S,4R)-(-)-2-phenyl-2-(2'-dimethylamino-ethoxy)-1,7,7-trimethyl-bicyclo[2.2.1]heptane], a new anxiolytic drug candidate, has been determined in rat, mouse, rabbit, dog, and human hepatocytes. Rat and rabbit cells were the most active, whereas the rate of metabolism was quite slow in human hepatocytes. During biotransformation, deramciclane underwent side chain modification and oxidation at several positions of the molecule. The side chain modification led to the formation of N-desmethyl deramciclane and phenylborneol. The oxidation of deramciclane resulted in several hydroxy-, carboxy-, and N-oxide derivatives. The hydroxylation took place at primary or secondary carbons of the camphor ring as well as at the side chain; furthermore, dihydroxylated derivatives were also found. The side chain-modified metabolites were also oxidized to hydroxy- or carboxy-derivatives. Conjugation of phase I metabolites, as a route of elimination, was also observed in rat, rabbit, and dog hepatocytes. Although there were some species differences in biotransformation of deramciclane, it was concluded that phase I metabolism in human liver cells seemed to be similar to the metabolism in the hepatocytes isolated from rat. With careful approach, the rat model may be considered to be predictive for human metabolism of deramciclane. PMID:16118331

  14. Three Dimensional Primary Hepatocyte Culture

    NASA Technical Reports Server (NTRS)

    Yoffe, Boris

    1998-01-01

    Our results demonstrated for the first time the feasibility of culturing PHH in microgravity bioreactors that exceeded the longest period obtained using other methods. Within the first week of culture, isolated hepatocytes started to form aggregates, which continuously increased in size (up to 1 cm) and macroscopically appeared as a multidimensional tissue-like assembly. To improve oxygenation and nutrition within the spheroids we performed experiments with the biodegradable nonwoven fiber-based polymers made from PolyGlycolic Acid (PGA). It has been shown that PGA scaffolds stimulate isolated cells to regenerate tissue with defined sizes and shapes and are currently being studied for various tissue-engineering applications. Our data demonstrated that culturing hepatocytes in the presence of PGA scaffolds resulted in more efficient cell assembly and formations of larger cell spheroids (up to 3 cm in length, see figure). The histology of cell aggregates cultured with PGA showed polymer fibers with attached hepatocytes. We initiated experiments to co-culture primary human hepatocytes with human microvascular endothelial cells in the bioreactor. The presence of endothelial cells in co-cultures were established by immunohistochemistry using anti-CD34 monoclonal Ab. Our preliminary data demonstrated that cultures of purified hepatocytes with human microvascular endothelial cells exhibited better growth and expressed higher levels of albumin MRNA for a longer period of time than cultures of ppfified, primary human hepatocytes cultured alone. We also evaluated microsomal deethylation activity of hepatocytes cultured in the presence of endothelial cells.In summary, we have established liver cell culture, which mimicked the structure and function of the parent tissue.

  15. Gene expression profiling and differentiation assessment in primary human hepatocyte cultures, established hepatoma cell lines, and human liver tissues

    SciTech Connect

    Olsavsky, Katy M.; Page, Jeanine L.; Johnson, Mary C.; Zarbl, Helmut; Strom, Stephen C.; Omiecinski, Curtis J. . E-mail: cjo10@psu.edu

    2007-07-01

    Frequently, primary hepatocytes are used as an in vitro model for the liver in vivo. However, the culture conditions reported vary considerably, with associated variability in performance. In this study, we characterized the differentiation character of primary human hepatocytes cultured using a highly defined, serum-free two-dimensional sandwich system, one that configures hepatocytes with collagen I as the substratum together with a dilute extracellular matrix (Matrigel{sup TM}) overlay combined with a defined serum-free medium containing nanomolar levels of dexamethasone. Gap junctional communication, indicated by immunochemical detection of connexin 32 protein, was markedly enhanced in hepatocytes cultured in the Matrigel sandwich configuration. Whole genome expression profiling enabled direct comparison of liver tissues to hepatocytes and to the hepatoma-derived cell lines, HepG2 and Huh7. PANTHER database analyses were used to identify biological processes that were comparatively over-represented among probe sets expressed in the in vitro systems. The robustness of the primary hepatocyte cultures was reflected by the extent of unchanged expression character when compared directly to liver, with more than 77% of the probe sets unchanged in each of the over-represented categories, representing such genes as C/EBP{alpha}, HNF4{alpha}, CYP2D6, and ABCB1. In contrast, HepG2 and Huh7 cells were unchanged from the liver tissues for fewer than 48% and 55% of these probe sets, respectively. Further, hierarchical clustering of the hepatocytes, but not the cell lines, shifted from donor-specific to treatment-specific when the probe sets were filtered to focus on phenobarbital-inducible genes, indicative of the highly differentiated nature of the hepatocytes when cultured in a highly defined two-dimensional sandwich system.

  16. Functional 3D human primary hepatocyte spheroids made by co-culturing hepatocytes from partial hepatectomy specimens and human adipose-derived stem cells.

    PubMed

    No, Da Yoon; Lee, Seung-A; Choi, Yoon Young; Park, DoYeun; Jang, Ju Yun; Kim, Dong-Sik; Lee, Sang-Hoon

    2012-01-01

    We have generated human hepatocyte spheroids with uniform size and shape by co-culturing 1∶1 mixtures of primary human hepatocytes (hHeps) from partial hepatectomy specimens and human adipose-derived stem cells (hADSCs) in concave microwells. The hADSCs in spheroids could compensate for the low viability and improve the functional maintenance of hHeps. Co-cultured spheroids aggregated and formed compact spheroidal shapes more rapidly, and with a significantly higher viability than mono-cultured spheroids. The liver-specific functions of co-cultured spheroids were greater, although they contained half the number of hepatocytes as mono-cultured spheroids. Albumin secretion by co-cultured spheroids was 10% higher on day 7, whereas urea secretion was similar, compared with mono-cultured spheroids. A quantitative cytochrome P450 assay showed that the enzymatic activity of co-cultured spheroids cultured for 9 days was 28% higher than that of mono-cultured spheroids. These effects may be due to the transdifferentiation potential and paracrine healing effects of hADSCs on hHeps. These co-cultured spheroids may be useful for creating artificial three-dimensional hepatic tissue constructs and for cell therapy with limited numbers of human hepatocytes. PMID:23236387

  17. Long term cultures of primary human hepatocytes as an alternative to drug testing in animals.

    PubMed

    Ullrich, Anett; Stolz, Donna B; Ellis, Ewa C; Strom, Stephen C; Michalopoulos, George K; Hengstler, Jan G; Runge, Dieter

    2009-01-01

    Due to species differences, primary human hepatocytes are still the in vitro system of choice to analyse liver specific processes and functions. Human hepatocytes were cultured for several weeks in a serum-free two-dimensional culture system, which was used to study the effects of acetaminophen (APAP) on hepatocellular functions and vitality. Non-invasive determinations of albumin, urea and lactate dehydrogenase concentrations in cell culture supernatants allowed continuous monitoring for at least two weeks. APAP was applied every 4 days for 24 h. Each application reduced urea production by 25% and albumin synthesis by approximately 70% without any effects on cellular viability. After removal of the substance, hepatocellular functions returned to control levels within one (urea) to three (albumin) days. The repetitive analyses of APAP-mediated effects on cellular metabolism led to identical results for up to five cycles. The drug also caused reversible and repetitive ultrastructural modifications, in particular an almost complete replacement of rough endoplasmic reticulum by smooth endoplasmic reticulum and a massive degradation of glycogen stores. The data demonstrate the suitability of the culture system to serve as a model for repetitive testing of drug-mediated changes on hepatocellular functions, thereby reducing animal studies during drug development. PMID:20383475

  18. Genomic responses to hepatitis B virus (HBV) infection in primary human hepatocytes

    PubMed Central

    Ancey, Pierre-Benoit; Testoni, Barbara; Gruffaz, Marion; Cros, Marie-Pierre; Durand, Geoffroy; Le Calvez-Kelm, Florence; Durantel, David; Herceg, Zdenko; Hernandez-Vargas, Hector

    2015-01-01

    Viral infections are able to modify the host's cellular programs, with DNA methylation being a biological intermediate in this process. The extent to which viral infections deregulate gene expression and DNA methylation is not fully understood. In the case of Hepatitis B virus (HBV), there is evidence for an interaction between viral proteins and the host DNA methylation machinery. We studied the ability of HBV to modify the host transcriptome and methylome, using naturally infected primary human hepatocytes to better mimic the clinical setting. Gene expression was especially sensitive to culture conditions, independently of HBV infection. However, we identified non-random changes in gene expression and DNA methylation occurring specifically upon HBV infection. There was little correlation between expression and methylation changes, with transcriptome being a more sensitive marker of time-dependent changes induced by HBV. In contrast, a set of differentially methylated sites appeared early and were stable across the time course experiment. Finally, HBV-induced DNA methylation changes were defined by a specific chromatin context characterized by CpG-poor regions outside of gene promoters. These data support the ability of HBV to modulate host cell expression and methylation programs. In addition, it may serve as a reference for studies addressing the genome-wide consequences of HBV infection in human hepatocytes. PMID:26565721

  19. Mechanisms of acetaminophen-induced cell death in primary human hepatocytes

    SciTech Connect

    Xie, Yuchao; McGill, Mitchell R.; Dorko, Kenneth; Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson; Jaeschke, Hartmut

    2014-09-15

    Acetaminophen (APAP) overdose is the most prevalent cause of drug-induced liver injury in western countries. Numerous studies have been conducted to investigate the mechanisms of injury after APAP overdose in various animal models; however, the importance of these mechanisms for humans remains unclear. Here we investigated APAP hepatotoxicity using freshly isolated primary human hepatocytes (PHH) from either donor livers or liver resections. PHH were exposed to 5 mM, 10 mM or 20 mM APAP over a period of 48 h and multiple parameters were assessed. APAP dose-dependently induced significant hepatocyte necrosis starting from 24 h, which correlated with the clinical onset of human liver injury after APAP overdose. Interestingly, cellular glutathione was depleted rapidly during the first 3 h. APAP also resulted in early formation of APAP-protein adducts (measured in whole cell lysate and in mitochondria) and mitochondrial dysfunction, indicated by the loss of mitochondrial membrane potential after 12 h. Furthermore, APAP time-dependently triggered c-Jun N-terminal kinase (JNK) activation in the cytosol and translocation of phospho-JNK to the mitochondria. Both co-treatment and post-treatment (3 h) with the JNK inhibitor SP600125 reduced JNK activation and significantly attenuated cell death at 24 h and 48 h after APAP. The clinical antidote N-acetylcysteine offered almost complete protection even if administered 6 h after APAP and a partial protection when given at 15 h. Conclusion: These data highlight important mechanistic events in APAP toxicity in PHH and indicate a critical role of JNK in the progression of injury after APAP in humans. The JNK pathway may represent a therapeutic target in the clinic. - Highlights: • APAP reproducibly causes cell death in freshly isolated primary human hepatocytes. • APAP induces adduct formation, JNK activation and mitochondrial dysfunction in PHH. • Mitochondrial adducts and JNK translocation are delayed in PHH compared to

  20. Two compartment model of diazepam biotransformation in an organotypical culture of primary human hepatocytes

    SciTech Connect

    Acikgoez, Ali; Karim, Najibulla; Giri, Shibashish; Schmidt-Heck, Wolfgang; Bader, Augustinus

    2009-01-15

    Drug biotransformation is one of the most important parameters of preclinical screening tests for the registration of new drug candidates. Conventional existing tests rely on nonhuman models which deliver an incomplete metabolic profile of drugs due to the lack of proper CYP450 expression as seen in human liver in vivo. In order to overcome this limitation, we used an organotypical model of human primary hepatocytes for the biotransformation of the drug diazepam with special reference to metabolites in both the cell matrix phase and supernatant and its interaction of three inducers (phenobarbital, dexamethasone, aroclor 1254) in different time responses (1, 2, 4, 8, 24 h). Phenobarbital showed the strongest inducing effect in generating desmethyldiazepam and induced up to a 150 fold increase in oxazepam-content which correlates with the increased availability of the precursor metabolites (temazepam and desmethyldiazepam). Aroclor 1254 and dexamethasone had the strongest inducing effect on temazepam and the second strongest on oxazepam. The strong and overlapping inductive role of phenobarbital strengthens the participation of CYP2B6 and CYP3A in diazepam N-demethylation and CYP3A in temazepam formation. Aroclor 1254 preferentially generated temazepam due to the interaction with CYP3A and potentially CYP2C19. In parallel we represented these data in the form of a mathematical model with two compartments explaining the dynamics of diazepam metabolism with the effect of these other inducers in human primary hepatocytes. The model consists of ten differential equations, with one for each concentration c{sub i,j} (i = diazepam, temazepam, desmethyldiazepam, oxazepam, other metabolites) and one for each compartment (j = cell matrix phase, supernatant), respectively. The parameters p{sub k} (k = 1, 2, 3, 4, 13) are rate constants describing the biotransformation of diazepam and its metabolites and the other parameters (k = 5, 6, 7, 8, 9, 10, 11, 12, 14, 15) explain the

  1. Differential Transcriptional Responses to Interferon-α and Interferon-γ in Primary Human Hepatocytes

    PubMed Central

    Nanda, Santosh; Ji, Xuhuai; Calderon-Rodriguez, Gloria M.; Greenberg, Harry B.; Liang, T. Jake

    2010-01-01

    Interferon (IFN) plays a central role in the innate and adaptive antiviral immune responses. While IFN-α is currently approved for treating chronic hepatitis B and hepatitis C, in limited studies, IFN-γ has not been shown to be effective for chronic hepatitis B or C. To identify the potential mechanism underlying the differential antiviral effects of IFN-α and IFN-γ, we used cDNA microarray to profile the global transcriptional response to IFN-α and IFN-γ in primary human hepatocytes, the target cell population of hepatitis viruses. Our results reveal distinct patterns of gene expression induced by these 2 cytokines. Overall, IFN-α induces more genes than IFN-γ at the transcriptional level. Distinct sets of genes were induced by IFN-α and IFN-γ with limited overlaps. IFN-α induces gene transcription at an early time point (6 h) but not at a later time point (18 h), while the effects of IFN-γ are more prominent at 18 h than at 6 h, suggesting a delayed transcriptional response to IFN-γ in the hepatocytes. These findings indicate differential actions of IFN-α and IFN-γ in the context of therapeutic intervention for chronic viral infections in the liver. PMID:20038212

  2. Effect of Dimethyl Sulfoxide and Melatonin on the Isolation of Human Primary Hepatocytes.

    PubMed

    Solanas, Estela; Sostres, Carlos; Serrablo, Alejandro; García-Gil, Agustín; García, Joaquín J; Aranguren, Francisco J; Jiménez, Pilar; Hughes, Robin D; Serrano, María T

    2014-01-01

    The availability of fully functional human hepatocytes is critical for progress in human hepatocyte transplantation and the development of bioartificial livers and in vitro liver systems. However, the cell isolation process impairs the hepatocyte status and determines the number of viable cells that can be obtained. This study aimed to evaluate the effects of using dimethyl sulfoxide (DMSO) and melatonin in the human hepatocyte isolation protocol. Human hepatocytes were isolated from liver pieces resected from 10 patients undergoing partial hepatectomy. Each piece was dissected into 2 equally sized pieces and randomized, in 5 of 10 isolations, to perfusion with 1% DMSO-containing perfusion buffer or buffer also containing 5 mM melatonin using the 2-step collagenase perfusion technique (experiment 1), and in the other 5 isolations to standard perfusion or perfusion including 1% DMSO (experiment 2). Tissues perfused with DMSO yielded 70.6% more viable hepatocytes per gram of tissue (p = 0.076), with a 26.1% greater albumin production (p < 0.05) than those perfused with control buffer. Melatonin did not significantly affect (p > 0.05) any of the studied parameters, but cell viability, dehydrogenase activity, albumin production, urea secretion, and 7-ethoxycoumarin O-deethylase activity were slightly higher in cells isolated with melatonin-containing perfusion buffer compared to those isolated with DMSO. In conclusion, addition of 1% DMSO to the hepatocyte isolation protocol could improve the availability and functionality of hepatocytes for transplantation, but further studies are needed to clarify the mechanisms involved. PMID:26381499

  3. Xenobiotic Metabolizing Enzyme and Transporter Gene Expression in Primary Cultures of Human Hepatocytes Modulated by ToxCast Chemicals

    EPA Science Inventory

    ToxCast chemicals were assessed for induction or suppression of xenobiotic metabolizing enzyme and transporter gene expression using primary human hepatocytes. The mRNA levels of 14 target and 2 control genes were measured: ABCB1, ABCB11, ABCG2, SLCO1B1, CYP1A1, CYP1A2, CYP2B6, C...

  4. Modulation of Xenobiotic Metabolizing Enzyme and Transporter Gene Expression in Primary Cultures of Human Hepatocytes by ToxCast Chemicals

    EPA Science Inventory

    ToxCast chemicals were assessed for induction or suppression of xenobiotic metabolizing enzyme and transporter gene expression using primary human hepatocytes. The mRNA levels of 14 target and 2 control genes were measured: ABCB1, ABCB11, ABCG2, SLCO1B1, CYP1A1, CYP1A2, CYP2B6, C...

  5. Impact of Environmental Chemicals on the Transcriptome of Primary Human Hepatocytes: Potential for Health Effects.

    PubMed

    Mitchell, Robert D; Dhammi, Anirudh; Wallace, Andrew; Hodgson, Ernest; Roe, R Michael

    2016-08-01

    New paradigms for human health risk assessment of environmental chemicals emphasize the use of molecular methods and human-derived cell lines. In this study, we examined the effects of the insect repellent DEET (N,N-diethyl-m-toluamide) and the phenylpyrazole insecticide fipronil (fluocyanobenpyrazole) on transcript levels in primary human hepatocytes. These chemicals were tested individually and as a mixture. RNA-Seq showed that 100 μM DEET significantly increased transcript levels (α = 0.05) for 108 genes and lowered transcript levels for 64 genes and fipronil at 10 μM increased the levels of 2246 transcripts and decreased the levels for 1428 transcripts. Fipronil was 21-times more effective than DEET in eliciting changes, even though the treatment concentration was 10-fold lower for fipronil versus DEET. The mixture of DEET and fipronil produced a more than additive effect (levels increased for 3017 transcripts and decreased for 2087 transcripts). The transcripts affected for all chemical treatments were classified by GO analysis and mapped to chromosomes. The overall treatment responses, specific pathways, and individual transcripts affected were discussed at different levels of fold-change. Changes found in transcript levels in response to treatments will require further research to understand their importance in overall cellular, organ, and organismic function. PMID:27091632

  6. Biokinetics of chlorpromazine in primary rat and human hepatocytes and human HepaRG cells after repeated exposure.

    PubMed

    Broeders, Jessica J W; Parmentier, Céline; Truisi, Germaine L; Jossé, Rozenn; Alexandre, Eliane; Savary, Camille C; Hewitt, Philip G; Mueller, Stefan O; Guillouzo, André; Richert, Lysiane; van Eijkeren, Jan C H; Hermens, Joop L M; Blaauboer, Bas J

    2015-12-25

    Since drug induced liver injury is difficult to predict in animal models, more representative tests are needed to better evaluate these effects in humans. Existing in vitro systems hold great potential to detect hepatotoxicity of pharmaceuticals. In this study, the in vitro biokinetics of the model hepatotoxicant chlorpromazine (CPZ) were evaluated in three different liver cell systems after repeated exposure in order to incorporate repeated-dose testing into an in vitro assay. Primary rat and human hepatocytes, cultured in sandwich configuration and the human HepaRG cell line were treated daily with CPZ for 14 days. Samples were taken from medium, cells and well plastic at specific time points after the first and last exposure. The samples were analysed by HPLC-UV to determine the amount of CPZ in these samples. Based on cytotoxicity assays, the three models were tested at 1-2 μM CPZ, while the primary rat hepatocytes and the HepaRG cell line were in addition exposed to a higher concentration of 15-20 μM. Overall, the mass balance of CPZ decreased in the course of 24 h, indicating the metabolism of the compound within the cells. The largest decrease in parent compound was seen in the primary cultures; in the HepaRG cell cultures the mass balance only decreased to 50%. CPZ accumulated in the cells during the 14-day repeated exposure. Possible explanations for the accumulation of CPZ are a decrease in metabolism over time, inhibition of efflux transporters or binding to phospholipids. The biokinetics of CPZ differed between the three liver cell models and were influenced by specific cell properties as well as culture conditions. These results support the conclusion that in vitro biokinetics data are necessary to better interpret chemical-induced cytotoxicity data. PMID:25458484

  7. Phosphatidylethanolamine N-methyltransferase (PEMT) gene expression is induced by estrogen in human and mouse primary hepatocytes

    PubMed Central

    Resseguie, Mary; Song, Jiannan; Niculescu, Mihai D.; da Costa, Kerry-Ann; Randall, Thomas A.; Zeisel, Steven H.

    2008-01-01

    Choline is an essential nutrient for humans, though some of the requirement can be met by endogenous synthesis catalyzed by phosphatidylethanolamine N-methyltransferase (PEMT). Premenopausal women are relatively resistant to choline deficiency compared with postmenopausal women and men. Studies in animals suggest that estrogen treatment can increase PEMT activity. In this study we investigated whether the PEMT gene is regulated by estrogen. PEMT transcription was increased in a dose-dependent manner when primary mouse and human hepatocytes were treated with 17-β-estradiol for 24 h. This increased message was associated with an increase in protein expression and enzyme activity. In addition, we report a region that contains a perfect estrogen response element (ERE) ∼7.5 kb from the transcription start site corresponding to transcript variants NM_007169 and NM-008819 of the human and murine PEMT genes, respectively, three imperfect EREs in evolutionarily conserved regions and multiple imperfect EREs in nonconserved regions in the putative promoter regions. We predict that both the mouse and human PEMT genes have three unique transcription start sites, which are indicative of either multiple promoters and/or alternative splicing. This study is the first to explore the underlying mechanism of why dietary requirements for choline vary with estrogen status in humans.—Resseguie, M., Song, J., Niculescu, M. D., da Costa, K., Randall, T. A., Zeisel, S. H. Phosphatidylethanolamine N-methyltransferase (PEMT) gene expression is induced by estrogen in human and mouse primary hepatocytes. PMID:17456783

  8. Explanted Diseased Livers – A Possible Source of Metabolic Competent Primary Human Hepatocytes

    PubMed Central

    Krech, Till; DeTemple, Daphne; Jäger, Mark D.; Lehner, Frank; Manns, Michael P.; Klempnauer, Jürgen; Borlak, Jürgen; Bektas, Hueseyin; Vondran, Florian W. R.

    2014-01-01

    Being an integral part of basic, translational and clinical research, the demand for primary human hepatocytes (PHH) is continuously growing while the availability of tissue resection material for the isolation of metabolically competent PHH remains limited. To overcome current shortcomings, this study evaluated the use of explanted diseased organs from liver transplantation patients as a potential source of PHH. Therefore, PHH were isolated from resected surgical specimens (Rx-group; n = 60) and explanted diseased livers obtained from graft recipients with low labMELD-score (Ex-group; n = 5). Using established protocols PHH were subsequently cultured for a period of 7 days. The viability and metabolic competence of cultured PHH was assessed by the following parameters: morphology and cell count (CyQuant assay), albumin synthesis, urea production, AST-leakage, and phase I and II metabolism. Both groups were compared in terms of cell yield and metabolic function, and results were correlated with clinical parameters of tissue donors. Notably, cellular yields and viabilities were comparable between the Rx- and Ex-group and were 5.3±0.5 and 2.9±0.7×106 cells/g liver tissue with 84.3±1.3 and 76.0±8.6% viability, respectively. Moreover, PHH isolated from the Rx- or Ex-group did not differ in regards to loss of cell number in culture, albumin synthesis, urea production, AST-leakage, and phase I and II metabolism (measured by the 7-ethoxycoumarin-O-deethylase and uracil-5′-diphosphate-glucuronyltransferase activity). Likewise, basal transcript expressions of the CYP monooxygenases 1A1, 2C8 and 3A4 were comparable as was their induction when treated with a cocktail that consisted of 3-methylcholantren, rifampicin and phenobarbital, with increased expression of CYP 1A1 and 3A4 mRNA while transcript expression of CYP 2C8 was only marginally changed. In conclusion, the use of explanted diseased livers obtained from recipients with low labMELD-score might

  9. Characterization of primary human hepatocyte spheroids as a model system for drug-induced liver injury, liver function and disease.

    PubMed

    Bell, Catherine C; Hendriks, Delilah F G; Moro, Sabrina M L; Ellis, Ewa; Walsh, Joanne; Renblom, Anna; Fredriksson Puigvert, Lisa; Dankers, Anita C A; Jacobs, Frank; Snoeys, Jan; Sison-Young, Rowena L; Jenkins, Rosalind E; Nordling, Åsa; Mkrtchian, Souren; Park, B Kevin; Kitteringham, Neil R; Goldring, Christopher E P; Lauschke, Volker M; Ingelman-Sundberg, Magnus

    2016-01-01

    Liver biology and function, drug-induced liver injury (DILI) and liver diseases are difficult to study using current in vitro models such as primary human hepatocyte (PHH) monolayer cultures, as their rapid de-differentiation restricts their usefulness substantially. Thus, we have developed and extensively characterized an easily scalable 3D PHH spheroid system in chemically-defined, serum-free conditions. Using whole proteome analyses, we found that PHH spheroids cultured this way were similar to the liver in vivo and even retained their inter-individual variability. Furthermore, PHH spheroids remained phenotypically stable and retained morphology, viability, and hepatocyte-specific functions for culture periods of at least 5 weeks. We show that under chronic exposure, the sensitivity of the hepatocytes drastically increased and toxicity of a set of hepatotoxins was detected at clinically relevant concentrations. An interesting example was the chronic toxicity of fialuridine for which hepatotoxicity was mimicked after repeated-dosing in the PHH spheroid model, not possible to detect using previous in vitro systems. Additionally, we provide proof-of-principle that PHH spheroids can reflect liver pathologies such as cholestasis, steatosis and viral hepatitis. Combined, our results demonstrate that the PHH spheroid system presented here constitutes a versatile and promising in vitro system to study liver function, liver diseases, drug targets and long-term DILI. PMID:27143246

  10. Characterization of primary human hepatocyte spheroids as a model system for drug-induced liver injury, liver function and disease

    PubMed Central

    Bell, Catherine C.; Hendriks, Delilah F. G.; Moro, Sabrina M. L.; Ellis, Ewa; Walsh, Joanne; Renblom, Anna; Fredriksson Puigvert, Lisa; Dankers, Anita C. A.; Jacobs, Frank; Snoeys, Jan; Sison-Young, Rowena L.; Jenkins, Rosalind E.; Nordling, Åsa; Mkrtchian, Souren; Park, B. Kevin; Kitteringham, Neil R.; Goldring, Christopher E. P.; Lauschke, Volker M.; Ingelman-Sundberg, Magnus

    2016-01-01

    Liver biology and function, drug-induced liver injury (DILI) and liver diseases are difficult to study using current in vitro models such as primary human hepatocyte (PHH) monolayer cultures, as their rapid de-differentiation restricts their usefulness substantially. Thus, we have developed and extensively characterized an easily scalable 3D PHH spheroid system in chemically-defined, serum-free conditions. Using whole proteome analyses, we found that PHH spheroids cultured this way were similar to the liver in vivo and even retained their inter-individual variability. Furthermore, PHH spheroids remained phenotypically stable and retained morphology, viability, and hepatocyte-specific functions for culture periods of at least 5 weeks. We show that under chronic exposure, the sensitivity of the hepatocytes drastically increased and toxicity of a set of hepatotoxins was detected at clinically relevant concentrations. An interesting example was the chronic toxicity of fialuridine for which hepatotoxicity was mimicked after repeated-dosing in the PHH spheroid model, not possible to detect using previous in vitro systems. Additionally, we provide proof-of-principle that PHH spheroids can reflect liver pathologies such as cholestasis, steatosis and viral hepatitis. Combined, our results demonstrate that the PHH spheroid system presented here constitutes a versatile and promising in vitro system to study liver function, liver diseases, drug targets and long-term DILI. PMID:27143246

  11. Comparative Analysis of Temporal and Dose-Dependent TCDD-Elicited Gene Expression in Human, Mouse, and Rat Primary Hepatocytes

    PubMed Central

    Zacharewski, Timothy R.

    2013-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)–elicited time- and dose-dependent differential gene expression was compared in human, mouse, and rat primary hepatocytes. Comprehensive time course (10 nM TCDD or dimethyl sulfoxide vehicle control for 1, 2, 4, 8, 12, 24, and 48h) studies identified 495, 2305, and 711 differentially expressed orthologous genes in human, mouse, and rat hepatocytes, respectively. However, only 16 orthologs were differentially expressed across all three species, with the majority of orthologs exhibiting species-specific expression (399 human, 2097 mouse, and 533 rat), consistent with species-specific expression reported in other in vitro and in vivo comparative studies. TCDD also elicited the dose-dependent induction of 397 human, 100 mouse, and 443 rat genes at 12h and 615 human, 426 mouse, and 314 rat genes at 24h. Comparable EC50 values were obtained for AhR battery genes including Cyp1a1 (0.1 nM human, 0.05 nM mouse, 0.08 nM rat at 24h) and Tiparp (0.97 nM human, 0.63 nM mouse, 0.14 nM rat at 12h). Overrepresented functions and pathways included amino acid metabolism in humans, immune response in mice, and energy homeostasis in rats. Differentially expressed genes functionally associated with lipid transport, processing, and metabolism were overrepresented in all three species but exhibited species-specific expression consistent with the induction of hepatic steatosis in mice but not in rats following a single oral gavage of TCDD. Furthermore, human primary hepatocytes showed lipid accumulation following 48h of treatment with TCDD, suggesting that AhR-mediated steatosis in mice more closely resembles human hepatic fat accumulation compared with that in rats. Collectively, these results suggest that species-specific gene expression profiles mediate the species-specific effects of TCDD despite the conservation of the AhR and its signaling mechanism. PMID:23418086

  12. Efavirenz and 8-hydroxyefavirenz induce cell death via a JNK- and BimEL-dependent mechanism in primary human hepatocytes

    SciTech Connect

    Bumpus, Namandje N.

    2011-12-15

    Chronic use of efavirenz (EFV) has been linked to incidences of hepatotoxicity in patients receiving EFV to treat HIV-1. While recent studies have demonstrated that EFV stimulates hepatic cell death a role for the metabolites of efavirenz in this process has yet to be examined. In the present study, incubation of primary human hepatocytes with synthetic 8-hydroxyEFV (8-OHEFV), which is the primary metabolite of EFV, resulted in cell death, caspase-3 activation and reactive oxygen species formation. The metabolite exerted these effects at earlier time points and using lower concentrations than were required for the parent compound. In addition, pharmacological inhibition of cytochrome P450-dependent metabolism of EFV using 1-aminobenzotriazole markedly decreased reactive oxygen species formation and cell death. Treatment of primary human hepatocytes with EFV and 8-OHEFV also stimulated phosphorylation of c-Jun N-terminal kinase (JNK) as well as phosphorylation of the JNK substrate c-Jun. Further, the mRNA and protein expression of an isoform of Bim (Bcl-2 interacting mediator of cell death) denoted as BimEL, which is proapoptotic and has been shown to be modulated by JNK, was increased. Inhibition of JNK using SP600125 prevented the EFV- and 8-OHEFV-mediated cell death. Silencing of Bim using siRNA transfected into hepatocytes also prevented cell death resulting from 8-OHEFV-treatment. These data suggest that the oxidative metabolite 8-OHEFV is a more potent inducer of hepatic cell death than the parent compound EFV. Further, activation of the JNK signaling pathway and BimEL mRNA expression appear to be required for EFV- and 8-OHEFV-mediated hepatocyte death. -- Highlights: Black-Right-Pointing-Pointer 8-Hydroxyefavirenz is a more potent stimulator of cell death than efavirenz. Black-Right-Pointing-Pointer Efavirenz and 8-hydroxyefavirenz increase JNK activity and BimEL mRNA expression. Black-Right-Pointing-Pointer JNK and Bim are required for efavirenz- and 8

  13. Primary Human Hepatocytes Repopulate Livers of Mice After In Vitro Culturing and Lentiviral-Mediated Gene Transfer.

    PubMed

    Bierwolf, Jeanette; Volz, Tassilo; Lütgehetmann, Marc; Allweiss, Lena; Riecken, Kristoffer; Warlich, Michael; Fehse, Boris; Kalff, Joerg C; Dandri, Maura; Pollok, Joerg-Matthias

    2016-05-01

    Cell-based therapies represent a promising alternative to orthotopic liver transplantation. However, therapeutic effects are limited by low cell engraftment rates. We recently introduced a technique creating human hepatocyte spheroids for potential therapeutic application. The aim of this study was to evaluate whether these spheroids are suitable for engraftment in diseased liver tissues. Intrasplenic spheroid transplantation into immunodeficient uPA/SCID/beige mice was performed. Hepatocyte transduction ability prior to transplantation was tested by lentiviral labeling using red-green-blue (RGB) marking. Eight weeks after transplantation, animals were sacrificed and livers were analyzed by immunohistochemistry and immunofluorescence. To investigate human hepatocyte-specific gene expression profiles in mice, quantitative real-time-PCR was applied. Human albumin and alpha-1-antitrypsin concentrations in mouse serum were quantified to assess the levels of human chimerism. Precultured human hepatocytes reestablished their physiological liver tissue architecture and function upon transplantation in mice. Positive immunohistochemical labeling of the proliferating cell nuclear antigen revealed that human hepatocytes retained their in vivo proliferation capacity. Expression profiles of human genes analyzed in chimeric mouse livers resembled levels determined in native human tissue. Extensive vascularization of human cell clusters was detected by demonstration of von Willebrand factor activity. To model gene therapy approaches, lentiviral transduction was performed ex vivo and fluorescent microscopic imaging revealed maintenance of RGB marking in vivo. Altogether, this is the first report demonstrating that cultured and retroviral transduced human hepatocyte spheroids are able to engraft and maintain their regenerative potential in vivo. PMID:27068494

  14. Primary Human Hepatocytes Repopulate Livers of Mice After In Vitro Culturing and Lentiviral-Mediated Gene Transfer

    PubMed Central

    Bierwolf, Jeanette; Volz, Tassilo; Lütgehetmann, Marc; Allweiss, Lena; Riecken, Kristoffer; Warlich, Michael; Fehse, Boris; Kalff, Joerg C.; Dandri, Maura

    2016-01-01

    Cell-based therapies represent a promising alternative to orthotopic liver transplantation. However, therapeutic effects are limited by low cell engraftment rates. We recently introduced a technique creating human hepatocyte spheroids for potential therapeutic application. The aim of this study was to evaluate whether these spheroids are suitable for engraftment in diseased liver tissues. Intrasplenic spheroid transplantation into immunodeficient uPA/SCID/beige mice was performed. Hepatocyte transduction ability prior to transplantation was tested by lentiviral labeling using red-green-blue (RGB) marking. Eight weeks after transplantation, animals were sacrificed and livers were analyzed by immunohistochemistry and immunofluorescence. To investigate human hepatocyte-specific gene expression profiles in mice, quantitative real-time-PCR was applied. Human albumin and alpha-1-antitrypsin concentrations in mouse serum were quantified to assess the levels of human chimerism. Precultured human hepatocytes reestablished their physiological liver tissue architecture and function upon transplantation in mice. Positive immunohistochemical labeling of the proliferating cell nuclear antigen revealed that human hepatocytes retained their in vivo proliferation capacity. Expression profiles of human genes analyzed in chimeric mouse livers resembled levels determined in native human tissue. Extensive vascularization of human cell clusters was detected by demonstration of von Willebrand factor activity. To model gene therapy approaches, lentiviral transduction was performed ex vivo and fluorescent microscopic imaging revealed maintenance of RGB marking in vivo. Altogether, this is the first report demonstrating that cultured and retroviral transduced human hepatocyte spheroids are able to engraft and maintain their regenerative potential in vivo. PMID:27068494

  15. Xenobiotic-metabolizing enzyme and transporter gene expression in primary cultures of human hepatocytes modulated by ToxCast chemicals.

    PubMed

    Rotroff, Daniel M; Beam, Andrew L; Dix, David J; Farmer, Adam; Freeman, Kimberly M; Houck, Keith A; Judson, Richard S; LeCluyse, Edward L; Martin, Matthew T; Reif, David M; Ferguson, Stephen S

    2010-02-01

    Primary human hepatocyte cultures are useful in vitro model systems of human liver because when cultured under appropriate conditions the hepatocytes retain liver-like functionality such as metabolism, transport, and cell signaling. This model system was used to characterize the concentration- and time-response of the 320 ToxCast chemicals for changes in expression of genes regulated by nuclear receptors. Fourteen gene targets were monitored in quantitative nuclease protection assays: six representative cytochromes P-450, four hepatic transporters, three Phase II conjugating enzymes, and one endogenous metabolism gene involved in cholesterol synthesis. These gene targets are sentinels of five major signaling pathways: AhR, CAR, PXR, FXR, and PPARalpha. Besides gene expression, the relative potency and efficacy for these chemicals to modulate cellular health and enzymatic activity were assessed. Results demonstrated that the culture system was an effective model of chemical-induced responses by prototypical inducers such as phenobarbital and rifampicin. Gene expression results identified various ToxCast chemicals that were potent or efficacious inducers of one or more of the 14 genes, and by inference the 5 nuclear receptor signaling pathways. Significant relative risk associations with rodent in vivo chronic toxicity effects are reported for the five major receptor pathways. These gene expression data are being incorporated into the larger ToxCast predictive modeling effort. PMID:20574906

  16. Primary-like human hepatocytes genetically engineered to obtain proliferation competence display hepatic differentiation characteristics in monolayer and organotypical spheroid cultures.

    PubMed

    Herzog, Natalie; Hansen, Max; Miethbauer, Sebastian; Schmidtke, Kai-Uwe; Anderer, Ursula; Lupp, Amelie; Sperling, Sebastian; Seehofer, Daniel; Damm, Georg; Scheibner, Katrin; Küpper, Jan-Heiner

    2016-03-01

    Primary human hepatocytes are in great demand during drug development and in hepatology. However, both scarcity of tissue supply and donor variability of primary cells create a need for the development of alternative hepatocyte systems. By using a lentivirus vector system to transfer coding sequences of Upcyte® proliferation genes, we generated non-transformed stable hepatocyte cultures from human liver tissue samples. Here, we show data on newly generated proliferation-competent HepaFH3 cells investigated as conventional two-dimensional monolayer and as organotypical three-dimensional (3D) spheroid culture. In monolayer culture, HepaFH3 cells show typical cobblestone-like hepatocyte morphology and anchorage-dependent growth for at least 20 passages. Immunofluorescence staining revealed that characteristic hepatocyte marker proteins cytokeratin 8, human serum albumin, and cytochrome P450 (CYP) 3A4 were expressed. Quantitative real-time PCR analyses showed that expression levels of analyzed phase I CYP enzymes were at similar levels compared to those of cultured primary human hepatocytes and considerably higher than in the liver carcinoma cell line HepG2. Additionally, transcripts for phase II liver enzymes and transporter proteins OATP-C, MRP2, Oct1, and BSEP were present in HepaFH3. The cells produced urea and converted model compounds such as testosterone, diclofenac, and 7-OH-coumarin into phases I and II metabolites. Interestingly, phases I and II enzymes were expressed at about the same levels in convenient monolayer cultures and complex 3D spheroids. In conclusion, HepaFH3 cells and related primary-like hepatocyte lines seem to be promising tools for in vitro research of liver functions and as test system in drug development and toxicology analysis. PMID:26715207

  17. Similarities and Differences in the Expression of Drug-Metabolizing Enzymes between Human Hepatic Cell Lines and Primary Human HepatocytesS⃞

    PubMed Central

    Guo, Lei; Dial, Stacey; Shi, Leming; Branham, William; Liu, Jie; Fang, Jia-Long; Green, Bridgett; Deng, Helen; Kaput, Jim

    2011-01-01

    In addition to primary human hepatocytes, hepatoma cell lines, and transfected nonhepatoma, hepatic cell lines have been used for pharmacological and toxicological studies. However, a systematic evaluation and a general report of the gene expression spectra of drug-metabolizing enzymes and transporters (DMETs) in these in vitro systems are not currently available. To fill this information gap and to provide references for future studies, we systematically characterized the basal gene expression profiles of 251 drug-metabolizing enzymes in untreated primary human hepatocytes from six donors, four commonly used hepatoma cell lines (HepG2, Huh7, SK-Hep-1, and Hep3B), and one transfected human liver epithelial cell line. A large variation in DMET expression spectra was observed between hepatic cell lines and primary hepatocytes, with the complete absence or much lower abundance of certain DMETs in hepatic cell lines. Furthermore, the basal DMET expression spectra of five hepatic cell lines are summarized, providing references for researchers to choose carefully appropriate in vitro models for their studies of drug metabolism and toxicity, especially for studies with drugs in which toxicities are mediated through the formation of reactive metabolites. PMID:21149542

  18. Protocol for Isolation of Primary Human Hepatocytes and Corresponding Major Populations of Non-parenchymal Liver Cells.

    PubMed

    Kegel, Victoria; Deharde, Daniela; Pfeiffer, Elisa; Zeilinger, Katrin; Seehofer, Daniel; Damm, Georg

    2016-01-01

    Beside parenchymal hepatocytes, the liver consists of non-parenchymal cells (NPC) namely Kupffer cells (KC), liver endothelial cells (LEC) and hepatic Stellate cells (HSC). Two-dimensional (2D) culture of primary human hepatocyte (PHH) is still considered as the "gold standard" for in vitro testing of drug metabolism and hepatotoxicity. It is well-known that the 2D monoculture of PHH suffers from dedifferentiation and loss of function. Recently it was shown that hepatic NPC play a central role in liver (patho-) physiology and the maintenance of PHH functions. Current research focuses on the reconstruction of in vivo tissue architecture by 3D- and co-culture models to overcome the limitations of 2D monocultures. Previously we published a method to isolate human liver cells and investigated the suitability of these cells for their use in cell cultures in Experimental Biology and Medicine(1). Based on the broad interest in this technique the aim of this article was to provide a more detailed protocol for the liver cell isolation process including a video, which will allow an easy reproduction of this technique. Human liver cells were isolated from human liver tissue samples of surgical interventions by a two-step EGTA/collagenase P perfusion technique. PHH were separated from the NPC by an initial centrifugation at 50 x g. Density gradient centrifugation steps were used for removal of dead cells. Individual liver cell populations were isolated from the enriched NPC fraction using specific cell properties and cell sorting procedures. Beside the PHH isolation we were able to separate KC, LEC and HSC for further cultivation. Taken together, the presented protocol allows the isolation of PHH and NPC in high quality and quantity from one donor tissue sample. The access to purified liver cell populations could allow the creation of in vivo like human liver models. PMID:27077489

  19. Predictivity of dog co-culture model, primary human hepatocytes and HepG2 cells for the detection of hepatotoxic drugs in humans

    SciTech Connect

    Atienzar, Franck A.; Novik, Eric I.; Gerets, Helga H.; Parekh, Amit; Delatour, Claude; Cardenas, Alvaro; MacDonald, James; Yarmush, Martin L.; Dhalluin, Stéphane

    2014-02-15

    Drug Induced Liver Injury (DILI) is a major cause of attrition during early and late stage drug development. Consequently, there is a need to develop better in vitro primary hepatocyte models from different species for predicting hepatotoxicity in both animals and humans early in drug development. Dog is often chosen as the non-rodent species for toxicology studies. Unfortunately, dog in vitro models allowing long term cultures are not available. The objective of the present manuscript is to describe the development of a co-culture dog model for predicting hepatotoxic drugs in humans and to compare the predictivity of the canine model along with primary human hepatocytes and HepG2 cells. After rigorous optimization, the dog co-culture model displayed metabolic capacities that were maintained up to 2 weeks which indicates that such model could be also used for long term metabolism studies. Most of the human hepatotoxic drugs were detected with a sensitivity of approximately 80% (n = 40) for the three cellular models. Nevertheless, the specificity was low approximately 40% for the HepG2 cells and hepatocytes compared to 72.7% for the canine model (n = 11). Furthermore, the dog co-culture model showed a higher superiority for the classification of 5 pairs of close structural analogs with different DILI concerns in comparison to both human cellular models. Finally, the reproducibility of the canine system was also satisfactory with a coefficient of correlation of 75.2% (n = 14). Overall, the present manuscript indicates that the dog co-culture model may represent a relevant tool to perform chronic hepatotoxicity and metabolism studies. - Highlights: • Importance of species differences in drug development. • Relevance of dog co-culture model for metabolism and toxicology studies. • Hepatotoxicity: higher predictivity of dog co-culture vs HepG2 and human hepatocytes.

  20. Use of Primary Rat and Human Hepatocyte Sandwich Cultures for Activation of Indirect Carcinogens: Monitoring of DNA Strand Breaks and Gene Mutations in Co-cultured Cells.

    PubMed

    Fahrig, R; Rupp, M; Steinkamp-Zucht, A; Bader, A

    1998-08-01

    Loss of cytochrome P-450 content is a common feature in conventional culture systems of primary hepatocytes. In contrast to the standard in vitro situation, in vivo each hepatocyte is exposed to an extracellular matrix (space of Disse) at two opposing basolateral surfaces. This in vivo symmetry has been reconstructed in vitro by culturing rat or human hepatocytes within two layers of collagen, thus forming a sandwich configuration. Activation of dimethylbenzanthracene (DMBA) or benzo[a]pyrene (BaP) was studied in rat and human hepatocytes. Genotoxic effects were studied in a three-dimensional co-culture model between sandwich hepatocytes and mammalian cells using the comet assay for detection of DNA strand breaks, and the HPRT test for detection of gene mutations. Sandwich hepatocytes generated active metabolites. The maintenance of metabolic properties in hepatocytes was dependent on extracellular matrix geometry. The number of DMBA- or BaP-induced genotoxic effects tended to be higher than in standard S-9 mix assays. While the ability to activate indirect carcinogens disappears within hours in primary hepatocytes, hepatocyte sandwich cultures enhance their ability to activate indirect carcinogens within 1 wk and retain this activity for up to 2 wk. This is the main advantage of the sandwich method over the more simple and conventional assays. While freshly isolated hepatocytes, regardless of whether in sandwich culture or in conventional assays, are injured by the isolation procedure and possess a corresponding reduced activation ability, hepatocytes in sandwich cultures recover over the course of a few days, and acquire a much higher ability to activate indirect carcinogens. Consequently, the indirect carcinogens BaP and DMBA, which were ineffective (BaP) or exhibited only weak effects (DMBA) at a concentration of 160nmol/ml in 1-2-day-old hepatocytes, were clearly effective (BaP) or showed about a threefold increase in genotoxicity (DMBA) in 8-day

  1. Transcriptional profiling suggests that Nevirapine and Ritonavir cause drug induced liver injury through distinct mechanisms in primary human hepatocytes.

    PubMed

    Terelius, Ylva; Figler, Robert A; Marukian, Svetlana; Collado, Maria S; Lawson, Mark J; Mackey, Aaron J; Manka, David; Qualls, Charles W; Blackman, Brett R; Wamhoff, Brian R; Dash, Ajit

    2016-08-01

    Drug induced liver injury (DILI), a major cause of pre- and post-approval failure, is challenging to predict pre-clinically due to varied underlying direct and indirect mechanisms. Nevirapine, a non-nucleoside reverse transcriptase inhibitor (NNRTI) and Ritonavir, a protease inhibitor, are antiviral drugs that cause clinical DILI with different phenotypes via different mechanisms. Assessing DILI in vitro in hepatocyte cultures typically requires drug exposures significantly higher than clinical plasma Cmax concentrations, making clinical interpretations of mechanistic pathway changes challenging. We previously described a system that uses liver-derived hemodynamic blood flow and transport parameters to restore primary human hepatocyte biology, and drug responses at concentrations relevant to in vivo or clinical exposure levels. Using this system, primary hepatocytes from 5 human donors were exposed to concentrations approximating clinical therapeutic and supra-therapeutic levels of Nevirapine (11.3 and 175.0 μM) and Ritonavir (3.5 and 62.4 μM) for 48 h. Whole genome transcriptomics was performed by RNAseq along with functional assays for metabolic activity and function. We observed effects at both doses, but a greater number of genes were differentially expressed with higher probability at the toxic concentrations. At the toxic doses, both drugs showed direct cholestatic potential with Nevirapine increasing bile synthesis and Ritonavir inhibiting bile acid transport. Clear differences in antigen presentation were noted, with marked activation of MHC Class I by Nevirapine and suppression by Ritonavir. This suggests CD8+ T cell involvement for Nevirapine and possibly NK Killer cells for Ritonavir. Both compounds induced several drug metabolizing genes (including CYP2B6, CYP3A4 and UGT1A1), mediated by CAR activation in Nevirapine and PXR in Ritonavir. Unlike Ritonavir, Nevirapine did not increase fatty acid synthesis or activate the respiratory electron chain

  2. Nonsterol Isoprenoids Activate Human Constitutive Androstane Receptor in an Isoform-Selective Manner in Primary Cultured Mouse Hepatocytes.

    PubMed

    Rondini, Elizabeth A; Duniec-Dmuchowski, Zofia; Kocarek, Thomas A

    2016-04-01

    Our laboratory previously reported that accumulation of nonsterol isoprenoids following treatment with the squalene synthase inhibitor, squalestatin 1 (SQ1) markedly induced cytochrome P450 (CYP)2B1 mRNA and reporter activity in primary cultured rat hepatocytes, which was dependent on activation of the constitutive androstane receptor (CAR). The objective of the current study was to evaluate whether isoprenoids likewise activate murine CAR (mCAR) or one or more isoforms of human CAR (hCAR) produced by alternative splicing (SPTV, hCAR2; APYLT, hCAR3). We found that SQ1 significantly induced Cyp2b10 mRNA (∼3.5-fold) in primary hepatocytes isolated from both CAR-wild-type and humanized CAR transgenic mice, whereas the 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor pravastatin had no effect. In the absence of CAR, basal Cyp2b10 mRNA levels were reduced by 28-fold and the effect of SQ1 on Cyp2b10 induction was attenuated. Cotransfection with an expression plasmid for hCAR1, but not hCAR2 or hCAR3, mediated SQ1-induced CYP2B1 and CYP2B6 reporter activation in hepatocytes isolated from CAR-knockout mice. This effect was also observed following treatment with the isoprenoid trans,trans-farnesol. The direct agonist CITCO increased interaction of hCAR1, hCAR2, and hCAR3 with steroid receptor coactivator-1. However, no significant effect on coactivator recruitment was observed with SQ1, suggesting an indirect activation mechanism. Further results from an in vitro ligand binding assay demonstrated that neither farnesol nor other isoprenoids are direct ligands for hCAR1. Collectively, our findings demonstrate that SQ1 activates CYP2B transcriptional responses through farnesol metabolism in an hCAR1-dependent manner. Further, this effect probably occurs through an indirect mechanism. PMID:26798158

  3. Quantitative Nuclease Protection Assays (qNPA) as Windows into Chemical-Induced Adaptive Response in Cultures of Primary Human Hepatocytes (Concentration and Time-Response)

    EPA Science Inventory

    Cultures of primary human hepatocytes have been shown to be dynamic in vitro model systems that retain liver-like functionality (e.g. metabolism, transport, induction). We have utilized these culture models to interrogate 309 ToxCast chemicals. The study design characterized both...

  4. Increased reprogramming of human fetal hepatocytes compared with adult hepatocytes in feeder-free conditions.

    PubMed

    Hansel, Marc C; Gramignoli, Roberto; Blake, William; Davila, Julio; Skvorak, Kristen; Dorko, Kenneth; Tahan, Veysel; Lee, Brian R; Tafaleng, Edgar; Guzman-Lepe, Jorge; Soto-Gutierrez, Alejandro; Fox, Ira J; Strom, Stephen C

    2014-01-01

    Hepatocyte transplantation has been used to treat liver disease. The availability of cells for these procedures is quite limited. Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) may be a useful source of hepatocytes for basic research and transplantation if efficient and effective differentiation protocols were developed and problems with tumorigenicity could be overcome. Recent evidence suggests that the cell of origin may affect hiPSC differentiation. Thus, hiPSCs generated from hepatocytes may differentiate back to hepatocytes more efficiently than hiPSCs from other cell types. We examined the efficiency of reprogramming adult and fetal human hepatocytes. The present studies report the generation of 40 hiPSC lines from primary human hepatocytes under feeder-free conditions. Of these, 37 hiPSC lines were generated from fetal hepatocytes, 2 hiPSC lines from normal hepatocytes, and 1 hiPSC line from hepatocytes of a patient with Crigler-Najjar syndrome, type 1. All lines were confirmed reprogrammed and expressed markers of pluripotency by gene expression, flow cytometry, immunocytochemistry, and teratoma formation. Fetal hepatocytes were reprogrammed at a frequency over 50-fold higher than adult hepatocytes. Adult hepatocytes were only reprogrammed with six factors, while fetal hepatocytes could be reprogrammed with three (OCT4, SOX2, NANOG) or four factors (OCT4, SOX2, NANOG, LIN28 or OCT4, SOX2, KLF4, C-MYC). The increased reprogramming efficiency of fetal cells was not due to increased transduction efficiency or vector toxicity. These studies confirm that hiPSCs can be generated from adult and fetal hepatocytes including those with genetic diseases. Fetal hepatocytes reprogram much more efficiently than adult hepatocytes, although both could serve as useful sources of hiPSC-derived hepatocytes for basic research or transplantation. PMID:23394081

  5. Development of an in vitro high content imaging assay for quantitative assessment of CAR-dependent mouse, rat, and human primary hepatocyte proliferation.

    PubMed

    Soldatow, Valerie; Peffer, Richard C; Trask, O Joseph; Cowie, David E; Andersen, Melvin E; LeCluyse, Edward; Deisenroth, Chad

    2016-10-01

    Rodent liver tumors promoted by constitutive androstane receptor (CAR) activation are known to be mediated by key events that include CAR-dependent gene expression and hepatocellular proliferation. Here, an in vitro high content imaging based assay was developed for quantitative assessment of nascent DNA synthesis in primary hepatocyte cultures from mouse, rat, and human species. Detection of DNA synthesis was performed using direct DNA labeling with the nucleoside analog 5-ethynyl-2'-deoxyuridine (EdU). The assay was multiplexed to enable direct quantitation of DNA synthesis, cytotoxicity, and cell count endpoints. An optimized defined medium cocktail was developed to sensitize hepatocytes to cell cycle progression. The baseline EdU response to defined medium was greatest for mouse, followed by rat, and then human. Hepatocytes from all three species demonstrated CAR activation in response to the CAR agonists TCPOBOP, CITCO, and phenobarbital based on increased gene expression for Cyp2b isoforms. When evaluated for a proliferation phenotype, TCPOBOP and CITCO exhibited significant dose-dependent increases in frequency of EdU labeling in mouse and rat hepatocytes that was not observed in hepatocytes from three human donors. The observed species differences are consistent with CAR activators inducing a proliferative response in rodents, a key event in the liver tumor mode of action that is not observed in humans. PMID:27530964

  6. Potency of individual bile acids to regulate bile acid synthesis and transport genes in primary human hepatocyte cultures.

    PubMed

    Liu, Jie; Lu, Hong; Lu, Yuan-Fu; Lei, Xiaohong; Cui, Julia Yue; Ellis, Ewa; Strom, Stephen C; Klaassen, Curtis D

    2014-10-01

    Bile acids (BAs) are known to regulate their own homeostasis, but the potency of individual bile acids is not known. This study examined the effects of cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), lithocholic acid (LCA) and ursodeoxycholic acid (UDCA) on expression of BA synthesis and transport genes in human primary hepatocyte cultures. Hepatocytes were treated with the individual BAs at 10, 30, and 100μM for 48 h, and RNA was extracted for real-time PCR analysis. For the classic pathway of BA synthesis, BAs except for UDCA markedly suppressed CYP7A1 (70-95%), the rate-limiting enzyme of bile acid synthesis, but only moderately (35%) down-regulated CYP8B1 at a high concentration of 100μM. BAs had minimal effects on mRNA of two enzymes of the alternative pathway of BA synthesis, namely CYP27A1 and CYP7B1. BAs increased the two major target genes of the farnesoid X receptor (FXR), namely the small heterodimer partner (SHP) by fourfold, and markedly induced fibroblast growth factor 19 (FGF19) over 100-fold. The BA uptake transporter Na(+)-taurocholate co-transporting polypeptide was unaffected, whereas the efflux transporter bile salt export pump was increased 15-fold and OSTα/β were increased 10-100-fold by BAs. The expression of the organic anion transporting polypeptide 1B3 (OATP1B3; sixfold), ATP-binding cassette (ABC) transporter G5 (ABCG5; sixfold), multidrug associated protein-2 (MRP2; twofold), and MRP3 (threefold) were also increased, albeit to lesser degrees. In general, CDCA was the most potent and effective BA in regulating these genes important for BA homeostasis, whereas DCA and CA were intermediate, LCA the least, and UDCA ineffective. PMID:25055961

  7. Inhibition of bile salt transport by drugs associated with liver injury in primary hepatocytes from human, monkey, dog, rat, and mouse.

    PubMed

    Zhang, Jie; He, Kan; Cai, Lining; Chen, Yu-Chuan; Yang, Yifan; Shi, Qin; Woolf, Thomas F; Ge, Weigong; Guo, Lei; Borlak, Jürgen; Tong, Weida

    2016-08-01

    Interference of bile salt transport is one of the underlying mechanisms for drug-induced liver injury (DILI). We developed a novel bile salt transport activity assay involving in situ biosynthesis of bile salts from their precursors in primary human, monkey, dog, rat, and mouse hepatocytes in suspension as well as LC-MS/MS determination of extracellular bile salts transported out of hepatocytes. Glycine- and taurine-conjugated bile acids were rapidly formed in hepatocytes and effectively transported into the extracellular medium. The bile salt formation and transport activities were time‒ and bile-acid-concentration‒dependent in primary human hepatocytes. The transport activity was inhibited by the bile salt export pump (BSEP) inhibitors ketoconazole, saquinavir, cyclosporine, and troglitazone. The assay was used to test 86 drugs for their potential to inhibit bile salt transport activity in human hepatocytes, which included 35 drugs associated with severe DILI (sDILI) and 51 with non-severe DILI (non-sDILI). Approximately 60% of the sDILI drugs showed potent inhibition (with IC50 values <50 μM), but only about 20% of the non-sDILI drugs showed this strength of inhibition in primary human hepatocytes and these drugs are associated only with cholestatic and mixed hepatocellular cholestatic (mixed) injuries. The sDILI drugs, which did not show substantial inhibition of bile salt transport activity, are likely to be associated with immune-mediated liver injury. Twenty-four drugs were also tested in monkey, dog, rat and mouse hepatocytes. Species differences in potency were observed with mouse being less sensitive than other species to inhibition of bile salt transport. In summary, a novel assay has been developed using hepatocytes in suspension from human and animal species that can be used to assess the potential for drugs and/or drug-derived metabolites to inhibit bile salt transport and/or formation activity. Drugs causing sDILI, except those by immune

  8. Modulation of aflatoxin B1-mediated genotoxicity in primary cultures of human hepatocytes by diindolylmethane, curcumin, and xanthohumols.

    PubMed

    Gross-Steinmeyer, Kerstin; Stapleton, Patricia L; Tracy, Julia H; Bammler, Theo K; Strom, Stephen C; Buhler, Donald R; Eaton, David L

    2009-12-01

    This study employed cultured human primary hepatocytes to investigate the ability of the putative chemopreventive phytochemicals curcumin (CUR), 3,3'-diindolylmethane (DIM), isoxanthohumol (IXN), or 8-prenylnaringenin (8PN) to reduce DNA adduct formation of the hepatocarcinogen aflatoxin B1 (AFB). Following 48 h of pretreatment, DIM and 8PN significantly increased AFB-DNA adduct levels, whereas CUR and IXN had no effect. DIM greatly enhanced the transcriptional expression of cytochrome P450 (CYP) 1A1 and CYP1A2 mRNA. Glutathione S-transferase mRNAs were not increased by any of the treatments. In vitro enzyme activity assays demonstrated that 8PN and DIM, but not CUR or IXN, inhibited human CYP1A1, CYP1A2, and CYP3A4 activities. To distinguish between treatment effects on transcription versus direct effects on enzyme activity for DIM, we evaluated the effects of pretreatment alone (transcriptional activation) versus cotreatment alone (enzyme inhibition). The results demonstrated that effects on gene expression, but not catalytic activity, are responsible for the observed effects of DIM on AFB-DNA adduct formation. The increase in AFB-DNA damage following DIM treatment may be explained through its substantial induction of CYP1A2 and/or its downregulation of GSTM1, both of which were significant. The increase in DNA damage by DIM raises potential safety risks for dietary supplements of DIM and its precursor indole-3-carbinol. PMID:19770484

  9. Data on gene and protein expression changes induced by apabetalone (RVX-208) in ex vivo treated human whole blood and primary hepatocytes.

    PubMed

    Wasiak, Sylwia; Gilham, Dean; Tsujikawa, Laura M; Halliday, Christopher; Norek, Karen; Patel, Reena G; McLure, Kevin G; Young, Peter R; Gordon, Allan; Kulikowski, Ewelina; Johansson, Jan; Sweeney, Michael; Wong, Norman C

    2016-09-01

    Apabetalone (RVX-208) inhibits the interaction between epigenetic regulators known as bromodomain and extraterminal (BET) proteins and acetyl-lysine marks on histone tails. Data presented here supports the manuscript published in Atherosclerosis "RVX-208, a BET-inhibitor for Treating Atherosclerotic Cardiovascular Disease, Raises ApoA-I/HDL and Represses Pathways that Contribute to Cardiovascular Disease" (Gilham et al., 2016) [1]. It shows that RVX-208 and a comparator BET inhibitor (BETi) JQ1 increase mRNA expression and production of apolipoprotein A-I (ApoA-I), the main protein component of high density lipoproteins, in primary human and African green monkey hepatocytes. In addition, reported here are gene expression changes from a microarray-based analysis of human whole blood and of primary human hepatocytes treated with RVX-208. PMID:27570805

  10. Long-term exposure to abnormal glucose levels alters drug metabolism pathways and insulin sensitivity in primary human hepatocytes

    PubMed Central

    Davidson, Matthew D.; Ballinger, Kimberly R.; Khetani, Salman R.

    2016-01-01

    Hyperglycemia in type 2 diabetes mellitus has been linked to non-alcoholic fatty liver disease, which can progress to inflammation, fibrosis/cirrhosis, and hepatocellular carcinoma. Understanding how chronic hyperglycemia affects primary human hepatocytes (PHHs) can facilitate the development of therapeutics for these diseases. Conversely, elucidating the effects of hypoglycemia on PHHs may provide insights into how the liver adapts to fasting, adverse diabetes drug reactions, and cancer. In contrast to declining PHH monocultures, micropatterned co-cultures (MPCCs) of PHHs and 3T3-J2 murine embryonic fibroblasts maintain insulin-sensitive glucose metabolism for several weeks. Here, we exposed MPCCs to hypo-, normo- and hyperglycemic culture media for ~3 weeks. While albumin and urea secretion were not affected by glucose level, hypoglycemic MPCCs upregulated CYP3A4 enzyme activity as compared to other glycemic states. In contrast, hyperglycemic MPCCs displayed significant hepatic lipid accumulation in the presence of insulin, while also showing decreased sensitivity to insulin-mediated inhibition of glucose output relative to a normoglycemic control. In conclusion, we show for the first time that PHHs exposed to hypo- and hyperglycemia can remain highly functional, but display increased CYP3A4 activity and selective insulin resistance, respectively. In the future, MPCCs under glycemic states can aid in novel drug discovery and mechanistic investigations. PMID:27312339

  11. Long-term exposure to abnormal glucose levels alters drug metabolism pathways and insulin sensitivity in primary human hepatocytes.

    PubMed

    Davidson, Matthew D; Ballinger, Kimberly R; Khetani, Salman R

    2016-01-01

    Hyperglycemia in type 2 diabetes mellitus has been linked to non-alcoholic fatty liver disease, which can progress to inflammation, fibrosis/cirrhosis, and hepatocellular carcinoma. Understanding how chronic hyperglycemia affects primary human hepatocytes (PHHs) can facilitate the development of therapeutics for these diseases. Conversely, elucidating the effects of hypoglycemia on PHHs may provide insights into how the liver adapts to fasting, adverse diabetes drug reactions, and cancer. In contrast to declining PHH monocultures, micropatterned co-cultures (MPCCs) of PHHs and 3T3-J2 murine embryonic fibroblasts maintain insulin-sensitive glucose metabolism for several weeks. Here, we exposed MPCCs to hypo-, normo- and hyperglycemic culture media for ~3 weeks. While albumin and urea secretion were not affected by glucose level, hypoglycemic MPCCs upregulated CYP3A4 enzyme activity as compared to other glycemic states. In contrast, hyperglycemic MPCCs displayed significant hepatic lipid accumulation in the presence of insulin, while also showing decreased sensitivity to insulin-mediated inhibition of glucose output relative to a normoglycemic control. In conclusion, we show for the first time that PHHs exposed to hypo- and hyperglycemia can remain highly functional, but display increased CYP3A4 activity and selective insulin resistance, respectively. In the future, MPCCs under glycemic states can aid in novel drug discovery and mechanistic investigations. PMID:27312339

  12. Genomewide comparison of the inducible transcriptomes of nuclear receptors CAR, PXR and PPARα in primary human hepatocytes.

    PubMed

    Kandel, Benjamin A; Thomas, Maria; Winter, Stefan; Damm, Georg; Seehofer, Daniel; Burk, Oliver; Schwab, Matthias; Zanger, Ulrich M

    2016-09-01

    The ligand-activated nuclear receptor pregnane X receptor (PXR, NR1I2) and the constitutive androstane receptor (CAR, NR1I3) are two master transcriptional regulators of many important drug metabolizing enzymes and transporter genes (DMET) in response to xenobiotics including many drugs. The peroxisome proliferator-activated receptor alpha (PPARα, NR1C1), the target of lipid lowering fibrate drugs, primarily regulates fatty acid catabolism and energy-homeostasis. Recent research has shown that there are substantial overlaps in the regulated genes of these receptors. For example, both CAR and PXR also modulate the transcription of key enzymes involved in lipid and glucose metabolism and PPARα also functions as a direct transcriptional regulator of important DMET genes including cytochrome P450s CYP3A4 and CYP2C8. Despite their important and widespread influence on liver metabolism, comparative data are scarce, particularly at a global level and in humans. The major objective of this study was to directly compare the genome-wide transcriptional changes elucidated by the activation of these three nuclear receptors in primary human hepatocytes. Cultures from six individual donors were treated with the prototypical ligands for CAR (CITCO), PXR (rifampicin) and PPARα (WY14,643) or DMSO as vehicle control. Genomewide mRNA profiles determined with Affymetrix microarrays were analyzed for differentially expressed genes and metabolic functions. The results confirmed known prototype target genes and revealed strongly overlapping sets of coregulated but also distinctly regulated and novel responsive genes and pathways. The results further specify the role of PPARα as a regulator of drug metabolism and the role of the xenosensors PXR and CAR in lipid metabolism and energy homeostasis. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie. PMID:26994748

  13. A study of the mechanism of in vitro cytotoxicity of metal oxide nanoparticles using catfish primary hepatocytes and human HepG2 cells.

    PubMed

    Wang, Yonggang; Aker, Winfred G; Hwang, Huey-min; Yedjou, Clement G; Yu, Hongtao; Tchounwou, Paul B

    2011-10-15

    Nanoparticles (NPs), including nanometal oxides, are being used in diverse applications such as medicine, clothing, cosmetics and food. In order to promote the safe development of nanotechnology, it is essential to assess the potential adverse health consequences associated with human exposure. The liver is a target site for NP toxicity, due to NP accumulation within it after ingestion, inhalation or absorption. The toxicity of nano-ZnO, TiO(2), CuO and Co(3)O(4) was investigated using a primary culture of channel catfish hepatocytes and human HepG2 cells as in vitro model systems for assessing the impact of metal oxide NPs on human and environmental health. Some mechanisms of nanotoxicity were determined by using phase contrast inverted microscopy, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, reactive oxygen species (ROS) assays, and flow cytometric assays. Nano-CuO and ZnO showed significant toxicity in both HepG2 cells and catfish primary hepatocytes. The results demonstrate that HepG2 cells are more sensitive than catfish primary hepatocytes to the toxicity of metal oxide NPs. The overall ranking of the toxicity of metal oxides to the test cells is as follows: TiO(2)

  14. Comparative Localization and Functional Activity of the Main Hepatobiliary Transporters in HepaRG Cells and Primary Human Hepatocytes.

    PubMed

    Bachour-El Azzi, Pamela; Sharanek, Ahmad; Burban, Audrey; Li, Ruoya; Guével, Rémy Le; Abdel-Razzak, Ziad; Stieger, Bruno; Guguen-Guillouzo, Christiane; Guillouzo, André

    2015-05-01

    The role of hepatobiliary transporters in drug-induced liver injury remains poorly understood. Various in vivo and in vitro biological approaches are currently used for studying hepatic transporters; however, appropriate localization and functional activity of these transporters are essential for normal biliary flow and drug transport. Human hepatocytes (HHs) are considered as the most suitable in vitro cell model but erratic availability and inter-donor functional variations limit their use. In this work, we aimed to compare localization of influx and efflux transporters and their functional activity in differentiated human HepaRG hepatocytes with fresh HHs in conventional (CCHH) and sandwich (SCHH) cultures. All tested influx and efflux transporters were correctly localized to canalicular [bile salt export pump (BSEP), multidrug resistance-associated protein 2 (MRP2), multidrug resistance protein 1 (MDR1), and MDR3] or basolateral [Na(+)-taurocholate co-transporting polypeptide (NTCP) and MRP3] membrane domains and were functional in all models. Contrary to other transporters, NTCP and BSEP were less abundant and active in HepaRG cells, cellular uptake of taurocholate was 2.2- and 1.4-fold and bile excretion index 2.8- and 2.6-fold lower, than in SCHHs and CCHHs, respectively. However, when taurocholate canalicular efflux was evaluated in standard and divalent cation-free conditions in buffers or cell lysates, the difference between the three models did not exceed 9.3%. Interestingly, cell imaging showed higher bile canaliculi contraction/relaxation activity in HepaRG hepatocytes and larger bile canaliculi networks in SCHHs. Altogether, our results bring new insights in mechanisms involved in bile acids accumulation and excretion in HHs and suggest that HepaRG cells represent a suitable model for studying hepatobiliary transporters and drug-induced cholestasis. PMID:25690737

  15. Interspecies differences in metabolism of arsenic by cultured primary hepatocytes

    SciTech Connect

    Drobna, Zuzana; Walton, Felecia S.; Harmon, Anne W.; Thomas, David J.; Styblo, Miroslav

    2010-05-15

    Biomethylation is the major pathway for the metabolism of inorganic arsenic (iAs) in many mammalian species, including the human. However, significant interspecies differences have been reported in the rate of in vivo metabolism of iAs and in yields of iAs metabolites found in urine. Liver is considered the primary site for the methylation of iAs and arsenic (+3 oxidation state) methyltransferase (As3mt) is the key enzyme in this pathway. Thus, the As3mt-catalyzed methylation of iAs in the liver determines in part the rate and the pattern of iAs metabolism in various species. We examined kinetics and concentration-response patterns for iAs methylation by cultured primary hepatocytes derived from human, rat, mice, dog, rabbit, and rhesus monkey. Hepatocytes were exposed to [{sup 73}As]arsenite (iAs{sup III}; 0.3, 0.9, 3.0, 9.0 or 30 nmol As/mg protein) for 24 h and radiolabeled metabolites were analyzed in cells and culture media. Hepatocytes from all six species methylated iAs{sup III} to methylarsenic (MAs) and dimethylarsenic (DMAs). Notably, dog, rat and monkey hepatocytes were considerably more efficient methylators of iAs{sup III} than mouse, rabbit or human hepatocytes. The low efficiency of mouse, rabbit and human hepatocytes to methylate iAs{sup III} was associated with inhibition of DMAs production by moderate concentrations of iAs{sup III} and with retention of iAs and MAs in cells. No significant correlations were found between the rate of iAs methylation and the thioredoxin reductase activity or glutathione concentration, two factors that modulate the activity of recombinant As3mt. No associations between the rates of iAs methylation and As3mt protein structures were found for the six species examined. Immunoblot analyses indicate that the superior arsenic methylation capacities of dog, rat and monkey hepatocytes examined in this study may be associated with a higher As3mt expression. However, factors other than As3mt expression may also contribute to

  16. Cellular impact of combinations of endosulfan, atrazine, and chlorpyrifos on human primary hepatocytes and HepaRG cells after short and chronic exposures.

    PubMed

    Nawaz, Ahmad; Razpotnik, Andrej; Rouimi, Patrick; de Sousa, Georges; Cravedi, Jean Pierre; Rahmani, Roger

    2014-02-01

    Chronic exposure to low doses of pesticides present in the environment is increasingly suspected to cause major health issues to humans. Toxicological evaluations become more complex when the exposure concerns chemical combinations. Atrazine, chlorpyrifos, and endosulfan are pesticides used worldwide in agriculture and are therefore currently found at residual levels in food and the environment, even in countries in which they are now banned. Our study aimed to use Real-Time Cell Impedance Analyzer to investigate changes in phenotypical status of primary human hepatocytes and differentiated HepaRG cells induced by short and chronic exposures to these three chemicals. In contrast to the traditionally used endpoint cytotoxicity test, this technology allows kinetic measurements in real-time throughout the entire experiment. Our data show significantly higher cytotoxic effects of mixtures as compared to individual pesticides and a greater susceptibility of human hepatocytes as compared to HepaRG to short-term exposure (24 h). Repeated exposure over 2 weeks to endosulfan and endosulfan-containing mixture induced HepaRG cell death in a time- and dose-dependent manner. Of the typical genes involved in metabolism and cell-response to xenobiotics, we found an exposure time- and condition-dependent deregulation of the expression of CYP3A4 and UGT1A in HepaRG cells exposed to low doses of pesticides and mixtures. Our data demonstrate the usefulness of real-time cell monitoring in long-term toxicological evaluations of co-exposure to xenobiotics. In addition, they support but at the same time highlight certain limitations in the use of HepaRG cells as the gold standard liver cell model in toxicity studies. PMID:24343343

  17. IL-1 receptor antagonist (IL-1Ra) does not inhibit the production of C-reactive protein or serum amyloid A protein by human primary hepatocytes. Differential regulation in normal and tumour cells.

    PubMed Central

    Gabay, C; Genin, B; Mentha, G; Iynedjian, P B; Roux-Lombard, P; Guerne, P A

    1995-01-01

    The synthesis of some class 1 acute-phase proteins (APP), including C-reactive protein (CRP) and serum amyloid A (SAA) protein is completely blocked by the IL-1 receptor antagonist (IL-1Ra), whereas the production of fibrinogen, a class 2 APP, is increased by IL-1Ra in hepatoma cells, but this has never been tested in human hepatocytes in primary culture. Since previous studies on the contributions of cytokine inhibitors in connective tissues diseases suggested that IL-1 and tumour necrosis factor-alpha (TNF-alpha) might play an important role in the regulation of CRP, we decided to examine in more detail the respective roles of IL-1 beta, IL-6, and TNF-alpha and their inhibitors in the production of APP by human primary hepatocytes versus the hepatoma cell line PLC/PRF/5. In the hepatoma cell line, IL-1 beta and/or TNF-alpha had synergistic effects with IL-6 on the production of CRP and SAA. In contrast, these cytokines were devoid of effect in normal hepatocytes. The production of fibrinogen was increased by IL-6 and decreased by IL-1 (and TNF-alpha) in both cell types. The secretion of CRP and SAA by primary hepatocytes incubated with a cytokine-rich mononuclear cell-conditioned medium was totally unaffected by IL-1Ra or anti-TNF-alpha antibodies. In contrast, the addition of IL-1Ra increased the production of fibrinogen by both hepatoma cells and primary hepatocytes incubated with the mononuclear cell-conditioned medium. We therefore conclude that IL-1 beta and TNF-alpha do not exert any significant effect on the synthesis of CRP and SAA by human primary hepatocytes. Images Fig. 6 PMID:7743670

  18. INTERINDIVIDUAL VARIATION IN THE METABOLISM OF ARSENIC IN HUMAN HEPATOCYTES

    EPA Science Inventory


    The liver is the major site for the enzymatic methylation of inorganic arsenic (iAs) in humans. Primary cultures of normal human hepatocytes isolated from tissue obtained at surgery or from donor livers have been used to study interindividual variation in the capacity of live...

  19. The role of organic anion transporting polypeptides (OATPs/SLCOs) in the toxicity of different microcystin congeners in vitro: A comparison of primary human hepatocytes and OATP-transfected HEK293 cells

    SciTech Connect

    Fischer, A.; Hoeger, S.J.; Stemmer, K.; Feurstein, D.J.; Knobeloch, D.; Nussler, A.; Dietrich, D.R.

    2010-05-15

    Cellular uptake of microcystins (MCs), a family of cyclic cyanobacterial heptapeptide toxins, occurs via specific organic anion transporting polypeptides (OATPs), where MCs inhibit serine/threonine-specific protein phosphatase (PP). Despite comparable PP-inhibitory capacity, MCs differ greatly in their acute toxicity, thus raising the question whether this discrepancy results from MC-specific toxikokinetic rather than toxicodynamic differences. OATP-mediated uptake of MC congeners MCLR, -RR, -LW and -LF was compared in primary human hepatocytes and HEK293 cells stably expressing recombinant human OATP1B1/SLCO1B1 and OATP1B3/SLCO1B3 in the presence/absence of OATP substrates taurocholate (TC) and bromosulfophthalein (BSP) and measuring PP-inhibition and cytotoxicity. Control vector expressing HEK293 were resistant to MC cytotoxicity, while TC and BSP competition experiments reduced MC cytotoxicity in HEK293-OATP transfectants, thus confirming the requirement of OATPs for trans-membrane transport. Despite comparable PP-inhibiting capabilities, MCLW and -LF elicited cytotoxic effects at lower equimolar concentrations than MCLR and MCRR, hence suggesting congener selective transport into HEK293-OATP transfectants and primary human hepatocytes. Primary human hepatocytes appeared one order of magnitude more sensitive to MC congeners than the corresponding HEK293 -OATP transfectants. Although the latter maybe due to a much lower level of PPs in primary human hepatocytes, the presence of OATPs other than 1B1 or 1B3 may have added to an increased uptake of MCs. In view of the high sensitivity of human hepatocytes and currently MCLR-only based risk calculations, the actual risk of human MC-intoxication and ensuing liver damage could be underestimated in freshwater cyanobacterial blooms where MCLW and-LF predominate.

  20. Strategies for immortalization of primary hepatocytes

    PubMed Central

    Eva, Ramboer; Bram, De Craene; Joery, De Kock; Tamara, Vanhaecke; Geert, Berx; Vera, Rogiers; Mathieu, Vinken

    2014-01-01

    The liver has the unique capacity to regenerate in response to a damaging event. Liver regeneration is hereby largely driven by hepatocyte proliferation, which in turn relies on cell cycling. The hepatocyte cell cycle is a complex process that is tightly regulated by several well-established mechanisms. In vitro, isolated hepatocytes do not longer retain this proliferative capacity. However, in vitro cell growth can be boosted by immortalization of hepatocytes. Well-defined immortalization genes can be artificially overexpressed in hepatocytes or the cells can be conditionally immortalized leading to controlled cell proliferation. This paper discusses the current immortalization techniques and provides a state-of-the-art overview of the actually available immortalized hepatocyte-derived cell lines and their applications. PMID:24911463

  1. Enzyme induction in cryopreserved human hepatocyte cultures.

    PubMed

    Kafert-Kasting, Sabine; Alexandrova, Krassimira; Barthold, Marc; Laube, Britta; Friedrich, Gerhard; Arseniev, Lubomir; Hengstler, Jan G

    2006-03-15

    Freshly isolated human hepatocytes are considered as the gold standard for in vitro testing of drug candidates. Meanwhile also cryopreserved human hepatocyte suspensions are available. However, a drawback of these cells is the incalculability of attachment to the culture dish. Therefore, we established a technique freezing hepatocytes cultured on a collagen gel. After thawing damaged cells were removed to a certain extent by gentle washing with culture medium prior to adding an upper gel layer. The morphology of the resulting hepatocyte cultures could not be distinguished from that of non-frozen cells. However, basal activities of cytochrome P450 isoforms decreased in cryopreserved compared to non-frozen hepatocytes, as evidenced by analysis of testosterone hydroxylation (OHT) in positions 6beta, 16alpha, 2beta and 6alpha. Nevertheless, enzyme induction factors caused by 24 h incubation with 50 microM rifampicin were similar in cryopreserved and non-frozen hepatocytes. In cryopreserved hepatocytes rifampicin caused an increase in mean values of 6beta-OHT formation from 57.2 to 157.7 pmol/well/min (2.8-fold), compared to an increase from 115.8 to 269.1 pmol/well/min (2.3-fold) in non-frozen cells. Similarly, 16alpha- and 2beta-OHT showed induction factors of 2.4- and 2.3-fold in cryopreserved compared to 1.6- and 2.4-fold in non-frozen hepatocytes, respectively. In conclusion, human hepatocytes cryopreserved on collagen gels show a clear induction of CYP3A4 by rifampicin, although the basal activities are reduced compared to non-frozen cells. PMID:16473453

  2. Analysis of DNA strand breaks induced in rodent liver in vivo, hepatocytes in primary culture, and a human cell line by chlorinated acetic acids and chlorinated acetaldehydes

    SciTech Connect

    Chang, L.W.; Daniel, F.B. ); DeAngelo, A.B. )

    1992-01-01

    An alkaline unwinding assay was used to quantitate the induction of DNA strand breaks (DNA SB) in the livers of rats and mice treated in vivo, in rodent hepatocytes in primary culture, and in CCRF-CEM cells, a human lymphoblastic leukemia cell line, following treatment with tri-(TCA), di-(CA), and mono-(MCA) chloroacetic acid and their corresponding aldehydes, tri-(chloralhydrate, CH), di(DCAA) and mono-(CAA) chloroacetaldehyde. None of the chloracetic acids induced DNA SB in the livers of rats at 4 hr following a single administration of 1-10 mmole/kg. TCA (10 mmole/kg) and DCA (5 and 10 mmole/kg) did produce a small amount of strand breakage in mice (7% at 4hr) but not at 1 hr. N-nitrosodiethylamine (DENA), an established alkylating agent and a rodent hepatocarcinogen, produced DNA SB in the livers of both species. TCA, DCA, and MCA also failed to induce DNA strand breaks in splenocytes and epithelial cells derived from the stomach and duodenum of mice treated in vivo. None of the three chloroacetaldehydes induced DNA SB in either mouse or rat liver. These studies provide further evidence that the chloroacetic acids lack genotoxic activity not only in rodent liver, a tissue in that they induce tumors, but in a variety of other rodent tissues and cultured cell types. Two of the chloroacetaldehydes, DCAA and CAA, are direct acting DNA damaging agents in CCRF-CEM cells, but not in liver or splenocytes in vivo or in cultured hepatocytes. CH showed no activity in any system investigated. 58 refs., 6 figs., 2 tabs.

  3. Prediction of the metabolic clearance of benzophenone-2, and its interaction with isoeugenol and coumarin using cryopreserved human hepatocytes in primary culture.

    PubMed

    de Sousa, Georges; Teng, Sophie; Salle-Siri, Romain; Pery, Alexandre; Rahmani, Roger

    2016-04-01

    Benzophenone-2 (BP2) is widely used as a UV screen in both industrial products and cosmetic formulations, where it is frequently found associated with fragrance compounds, such as isoeugenol and coumarin. BP2 is now recognized as an endocrine disruptor, but to date, no information has been reported on its fate in humans. The intrinsic clearance (Clint) and metabolic interactions of BP2 were explored using cryopreserved human hepatocytes in primary cultures. In vitro kinetic experiments were performed to estimate the Michaelis-Menten parameters. The substrate depletion method demonstrated that isoeugenol was cleared more rapidly than BP2 or coumarin (Clint = 259, 94.7 and 0.40 μl/min/10(6) cells respectively). This vitro model was also used to study the metabolic interactions between BP2 and isoeugenol and coumarin. Coumarin exerted no effects on either isoeugenol or BP2 metabolism, because of its independent metabolic pathway (CYP2A6). Isoeugenol appeared to be a potent competitive substrate inhibitor of BP2 metabolism, equivalent to the specific UGT1A1 substrate: estradiol. Despite the fact that inhibition of UGT by xenobiotics is not usually considered to be a major concern, the involvement of UGT1A1 in BP2 metabolism may have pharmacokinetic and pharmacological consequences, due to the its polymorphisms in humans and its pure estrogenic effect. PMID:26829614

  4. LIVER REGENERATION STUDIES WITH RAT HEPATOCYTES IN PRIMARY CULTURE

    EPA Science Inventory

    Adult rat parenchymal hepatocytes in primary culture can be induced to enter into DNA synthesis and mitosis. The optimal conditions for hepatocyte replication are low plating density (less than 10,000 cells/sq cm) and 50% serum from two-thirds partially hepatectomized rats (48 hr...

  5. In Vitro Model for Hepatotoxicity Studies Based on Primary Human Hepatocyte Cultivation in a Perfused 3D Bioreactor System

    PubMed Central

    Knöspel, Fanny; Jacobs, Frank; Freyer, Nora; Damm, Georg; De Bondt, An; van den Wyngaert, Ilse; Snoeys, Jan; Monshouwer, Mario; Richter, Marco; Strahl, Nadja; Seehofer, Daniel; Zeilinger, Katrin

    2016-01-01

    Accurate prediction of the potential hepatotoxic nature of new pharmaceuticals remains highly challenging. Therefore, novel in vitro models with improved external validity are needed to investigate hepatic metabolism and timely identify any toxicity of drugs in humans. In this study, we examined the effects of diclofenac, as a model substance with a known risk of hepatotoxicity in vivo, in a dynamic multi-compartment bioreactor using primary human liver cells. Biotransformation pathways of the drug and possible effects on metabolic activities, morphology and cell transcriptome were evaluated. Formation rates of diclofenac metabolites were relatively stable over the application period of seven days in bioreactors exposed to 300 µM diclofenac (300 µM bioreactors (300 µM BR)), while in bioreactors exposed to 1000 µM diclofenac (1000 µM BR) metabolite concentrations declined drastically. The biochemical data showed a significant decrease in lactate production and for the higher dose a significant increase in ammonia secretion, indicating a dose-dependent effect of diclofenac application. The microarray analyses performed revealed a stable hepatic phenotype of the cells over time and the observed transcriptional changes were in line with functional readouts of the system. In conclusion, the data highlight the suitability of the bioreactor technology for studying the hepatotoxicity of drugs in vitro. PMID:27092500

  6. Effect of sex hormones on n-3 polyunsaturated fatty acid biosynthesis in HepG2 cells and in human primary hepatocytes.

    PubMed

    Sibbons, Charlene M; Brenna, J Thomas; Lawrence, Peter; Hoile, Samuel P; Clarke-Harris, Rebecca; Lillycrop, Karen A; Burdge, Graham C

    2014-01-01

    Female humans and rodents have been shown to have higher 22:6n-3 status and synthesis than males. It is unclear which sex hormone is involved. We investigated the specificity of the effects of physiological concentrations of sex hormones in vitro on the mRNA expression of genes involved in polyunsaturated fatty acid (PUFA) biosynthesis and on the conversion of [d5]-18:3n-3 to longer chain fatty acids. Progesterone, but not 17α-ethynylestradiol or testosterone, increased FADS2, FADS1, ELOVl 5 and ELOVl 2 mRNA expression in HepG2 cells, but only FADS2 in primary human hepatocytes. In HepG2 cells, these changes were accompanied by hypomethylation of specific CpG loci in the FADS2 promoter. Progesterone, not 17α-ethynylestradiol or testosterone, increased conversion of [d5]-18:3n-3 to 20:5n-3, 22:5n-3 and 22:6n-3. These findings show that progesterone increases n-3 PUFA biosynthesis by up-regulating the mRNA expression of genes involved in this pathway, possibly via changes in the epigenetic regulation of FADS2. PMID:24411721

  7. In vitro human metabolism of permethrin isomers alone or as a mixture and the formation of the major metabolites in cryopreserved primary hepatocytes.

    PubMed

    Willemin, M-E; Kadar, A; de Sousa, G; Leclerc, E; Rahmani, R; Brochot, C

    2015-06-01

    In vitro metabolism of permethrin, a pyrethroid insecticide, was assessed in primary human hepatocytes. In vitro kinetic experiments were performed to estimate the Michaelis-Menten parameters and the clearances or formation rates of the permethrin isomers (cis- and trans-) and three metabolites, cis- and trans-3-(2,2 dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (cis- and trans-DCCA) and 3-phenoxybenzoic acid (3-PBA). Non-specific binding and the activity of the enzymes involved in permethrin's metabolism (cytochromes P450 and carboxylesterases) were quantified. Trans-permethrin was cleared more rapidly than cis-permethrin with a 2.6-factor (25.7±0.6 and 10.1±0.3 μL/min/10(6) cells respectively). A 3-factor was observed between the formation rates of DCCA and 3-PBA obtained from trans- and cis-permethrin. For both isomers, the rate of formation of DCCA was higher than the one of 3-PBA. The metabolism of the isomers in mixture was also quantified. The co-incubation of isomers at different ratios showed the low inhibitory potential of cis- and trans-permethrin on each other. The estimates of the clearances and the formation rates in the co-incubation condition did not differ from the estimates obtained with a separate incubation. These metabolic parameters may be integrated in physiologically based pharmacokinetic (PBPK) models to predict the fate of permethrin and metabolites in the human body. PMID:25765475

  8. Inter-donor variability of phase I/phase II metabolism of three reference drugs in cryopreserved primary human hepatocytes in suspension and monolayer.

    PubMed

    den Braver-Sewradj, Shalenie P; den Braver, Michiel W; Vermeulen, Nico P E; Commandeur, Jan N M; Richert, Lysiane; Vos, J Chris

    2016-06-01

    Cytochrome P450s (CYPs), UDP-glucuronosyltransferases (UGTs) and sulfotransferases (SULTs) are the most important enzymes for metabolic clearance. Characterization of phase I and phase II metabolism of a given drug in cellular models is therefore important for an adequate interpretation of the role of drug metabolism in toxicity. We investigated phase I (CYP) and phase II (UGT and SULT) metabolism of three drugs related to drug-induced liver injury (DILI), namely acetaminophen (APAP), diclofenac (DF) and tolcapone (TC), in cryopreserved primary human hepatocytes from 5 donors in suspension and monolayer. The general phase II substrate 7-hydroxycoumarin (7-HC) was included for comparison. Our results show that the decrease in CYP, UGT and SULT activity after plating is substrate dependent. As a consequence the phase I/phase II metabolism ratio is significantly affected, with a shift in monolayer towards phase I metabolism for TC and towards phase II metabolism for APAP and DF. Inter-donor variability in drug metabolism is significant, especially in sulfation of 7-HC or APAP. As CYP, UGT and SULT metabolism may lead to bioactivation and/or detoxification of drugs, a changed ratio in phase I/phase II metabolism may have important consequences for metabolism-related toxicity. PMID:26921663

  9. Skatole (3-Methylindole) Is a Partial Aryl Hydrocarbon Receptor Agonist and Induces CYP1A1/2 and CYP1B1 Expression in Primary Human Hepatocytes

    PubMed Central

    Balaguer, Patrick; Ekstrand, Bo; Daujat-Chavanieu, Martine; Gerbal-Chaloin, Sabine

    2016-01-01

    Skatole (3-methylindole) is a product of bacterial fermentation of tryptophan in the intestine. A significant amount of skatole can also be inhaled during cigarette smoking. Skatole is a pulmonary toxin that induces the expression of aryl hydrocarbon receptor (AhR) regulated genes, such as cytochrome P450 1A1 (CYP1A1), in human bronchial cells. The liver has a high metabolic capacity for skatole and is the first organ encountered by the absorbed skatole; however, the effect of skatole in the liver is unknown. Therefore, we investigated the impact of skatole on hepatic AhR activity and AhR-regulated gene expression. Using reporter gene assays, we showed that skatole activates AhR and that this is accompanied by an increase of CYP1A1, CYP1A2 and CYP1B1 expression in HepG2-C3 and primary human hepatocytes. Specific AhR antagonists and siRNA-mediated AhR silencing demonstrated that skatole-induced CYP1A1 expression is dependent on AhR activation. The effect of skatole was reduced by blocking intrinsic cytochrome P450 activity and indole-3-carbinole, a known skatole metabolite, was a more potent inducer than skatole. Finally, skatole could reduce TCDD-induced CYP1A1 expression, suggesting that skatole is a partial AhR agonist. In conclusion, our findings suggest that skatole and its metabolites affect liver homeostasis by modulating the AhR pathway. PMID:27138278

  10. A food contaminant ochratoxin A suppresses pregnane X receptor (PXR)-mediated CYP3A4 induction in primary cultures of human hepatocytes.

    PubMed

    Doricakova, Aneta; Vrzal, Radim

    2015-11-01

    Ochratoxin A (OCHA) is a mycotoxin, which can be found in food such as coffee, wine, cereals, meat, nuts. Since it is absorbed via gastrointestinal tract, it is reasonable to anticipate that the liver will be the first organ to which OCHA comes into the contact before systemic circulation. Many xenobiotics are metabolically modified after the passage of the liver to biologically more active substances, sometimes with more harmful activity. Promoting own metabolism is often achieved via transcriptional regulation of biotransformation enzymes through ligand-activated transcription factors. Pregnane X receptor (PXR) belongs to such a group of regulators and it was demonstrated to be activated by many compounds of synthetic as well as natural origin. Our intention was to investigate if OCHA is capable of activating the PXR with consequent induction of PXR-regulated CYP3A4 gene. We found that OCHA does not activate PXR but displays antagonist-like behavior when combined with rifampicin (RIF) in gene reporter assay in human embryonal kidney cells (Hek293T). It was very weak inducer of CYP3A4 mRNA in primary cultures of human hepatocytes and it antagonized RIF-mediated CYP3A4 induction of mRNA as well as protein. In addition, it caused the decline of PXR protein as well as mRNA which was faster than that with actinomycin D, a transcription inhibitor. Since we found that OCHA induced the expression of miR-148a, which was described to regulate PXR expression, we conclude that antagonist-like behavior of OCHA is not due to the antagonism itself but due to the downregulation of PXR gene expression. Herein we provide important findings which bring a piece of puzzle into the understanding of mechanism of toxic action of ochratoxin A. PMID:26341324

  11. Profiling primaquine metabolites in primary human hepatocytes by UPLC-QTOF-MS with 13c stable isotope labeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Primaquine (PQ) is an important antimalarial agent because of its activity against exoerythrocytic forms of Plasmodium spp. However, hemolytic anemia is a dose-limiting side effect of primaquine therapy that limits its widespread use. The major plasma metabolite identified in humans and animals, car...

  12. TEMPORAL CHANGE IN GAP JUNCTION FUNCTION IN PRIMARY HEPATOCYTES

    EPA Science Inventory

    TEMPORAL CHANGES IN GAP JUNCTION FUNCTION IN PRIMARY *

    The objective of this study was to examine the reduction in gap junction communication (GJC) in primary hepatocytes due to coincident melatonin and magnetic field treatments to determine if these conditions could prov...

  13. Augmenter of liver regeneration (ALR) protects human hepatocytes against apoptosis

    SciTech Connect

    Ilowski, Maren; Kleespies, Axel; Toni, Enrico N. de; Donabauer, Barbara; Jauch, Karl-Walter; Hengstler, Jan G.; Thasler, Wolfgang E.

    2011-01-07

    Research highlights: {yields} ALR decreases cytochrome c release from mitochondria. {yields} ALR protects hepatocytes against apoptosis induction by ethanol, TRAIL, anti-Apo, TGF-{beta} and actinomycin D. {yields} ALR exerts a liver-specific anti-apoptotic effect. {yields} A possible medical usage of ALR regarding protection of liver cells during apoptosis inducing therapies. -- Abstract: Augmenter of liver regeneration (ALR) is known to support liver regeneration and to stimulate proliferation of hepatocytes. However, it is not known if ALR exerts anti-apoptotic effects in human hepatocytes and whether this protective effect is cell type specific. This is relevant, because compounds that protect the liver against apoptosis without undesired effects, such as protection of metastatic tumour cells, would be appreciated in several clinical settings. Primary human hepatocytes (phH) and organotypic cancer cell lines were exposed to different concentrations of apoptosis inducers (ethanol, TRAIL, anti-Apo, TGF-{beta}, actinomycin D) and cultured with or without recombinant human ALR (rhALR). Apoptosis was evaluated by the release of cytochrome c from mitochondria and by FACS with propidium iodide (PI) staining. ALR significantly decreased apoptosis induced by ethanol, TRAIL, anti-Apo, TGF-{beta} and actinomycin D. Further, the anti-apoptotic effect of ALR was observed in primary human hepatocytes and in HepG2 cells but not in bronchial (BC1), colonic (SW480), gastric (GC1) and pancreatic (L3.6PL) cell lines. Therefore, the hepatotrophic growth factor ALR acts in a liver specific manner with regards to both its mitogenic and its anti-apoptotic effect. Unlike the growth factors HGF and EGF, rhALR acts in a liver specific manner. Therefore, ALR is a promising candidate for further evaluation as a possible hepatoprotective factor in clinical settings.

  14. Tetracycline-induced steatosis in primary canine hepatocyte cultures.

    PubMed

    Amacher, D E; Martin, B A

    1997-12-01

    Primary hepatocyte cultures prepared from male beagle dog liver were used to determine susceptibility of the canine liver to tetracycline-induced steatosis. The effects of the drug on mitochondrial lipid metabolism and intracellular triglyceride accumulation were monitored at the same time that steatosis was detected by light microscopy and quantitated using lipid-specific stains. Exposure of primary canine hepatocyte cultures to tetracycline for 24-48 h resulted in concentration-dependent, significant increases in the Oil Red O-stained lipid inclusions. Microscopic examination of the total stained areas suggested that increases over control levels were due primarily to the increase in the size of the lipid inclusions rather than in the number. Biochemical analyses for triglyceride content and histological staining with Nile red, another neutral lipid-specific dye, confirmed a specific increase in intracellular triglyceride following a 24-h exposure to noncytotoxic levels of tetracycline beta-oxidation studies based on the oxidation of [14C]palmitic acid or [14C]palmitoyl carnitine demonstrated a concentration-dependent inhibition of mitochondrial but not peroxisomal beta-oxidation in hepatocytes after a 24-h exposure to tetracycline. In vitro incubation of tetracycline with mitochondria isolated from dog liver showed similar concentration-dependent inhibition. This study clearly indicates that the canine hepatocyte is susceptible to tetracycline-induced steatosis. Triglyceride accumulation was concomitant with the inhibition of mitochondrial lipid metabolism, indicating that this is a primary mechanism leading to steatosis in dog hepatocytes following tetracycline exposure. PMID:9441722

  15. Metabolism of lipoproteins by human fetal hepatocytes

    SciTech Connect

    Carr, B.R.

    1987-12-01

    The rate of clearance of lipoproteins from plasma appears to play a role in the development of atherogenesis. The liver may account for as much as two thirds of the removal of low-density lipoprotein and one third of the clearance of high-density lipoprotein in certain animal species and humans, mainly by receptor-mediated pathways. The purpose of the present investigation was to determine if human fetal hepatocytes maintained in vitro take up and degrade lipoproteins. We first determined that the maximal binding capacity of iodine 125-iodo-LDL was approximately 300 ng of low-density lipoprotein protein/mg of membrane protein and an apparent dissociation constant of approximately 60 micrograms low-density lipoprotein protein/ml in membranes prepared from human fetal liver. We found that the maximal uptake of (/sup 125/I)iodo-LDL and (/sup 125/I)iodo-HDL by fetal hepatocytes occurred after 12 hours of incubation. Low-density lipoprotein uptake preceded the appearance of degradation products by 4 hours, and thereafter the degradation of low-density lipoprotein increased linearly for at least 24 hours. In contrast, high-density lipoprotein was not degraded to any extent by fetal hepatocytes. (/sup 125/I)Iodo-LDL uptake and degradation were inhibited more than 75% by preincubation with low-density lipoprotein but not significantly by high-density lipoprotein, whereas (/sup 125/I)iodo-HDL uptake was inhibited 70% by preincubation with high-density lipoprotein but not by low-density lipoprotein. In summary, human fetal hepatocytes take up and degrade low-density lipoprotein by a receptor-mediated process similar to that described for human extrahepatic tissues.

  16. COVALENT BINDING OF TRICHLOROETHYLENE TO PROTEINS IN HUMAN AND RAT HEPATOCYTES. (R826409)

    EPA Science Inventory

    The environmental contaminant and occupational solvent trichloroethylene is metabolized to a reactive intermediate that covalently binds to specific hepatic proteins in exposed mice and rats. In order to compare covalent binding between humans and rodents, primary hepatocyte c...

  17. Human hepatocytes and endothelial cells in organotypic membrane systems.

    PubMed

    Salerno, Simona; Campana, Carla; Morelli, Sabrina; Drioli, Enrico; De Bartolo, Loredana

    2011-12-01

    The realization of organotypic liver model that exhibits stable phenotype is a major challenge in the field of liver tissue engineering. In this study we developed liver organotypic co-culture systems by using synthetic and biodegradable membranes with primary human hepatocytes and human umbilical vein endothelial cells (HUVEC). Synthetic membranes prepared by a polymeric blend constituted of modified polyetheretherketone (PEEK-WC) and polyurethane (PU) and biodegradable chitosan membranes were developed by phase inversion technique and used in homotypic and organotypic culture systems. The morphological and functional characteristics of cells in the organotypic co-culture membrane systems were evaluated in comparison with homotypic cultures and traditional systems. Hepatocytes in the organotypic co-culture systems exhibit compact polyhedral cells with round nuclei and well demarcated cell-cell borders like in vivo, as a result of heterotypic interaction with HUVECs. In addition HUVECs formed tube-like structures directly through the interactions with the membranes and hepatocytes and indirectly through the secretion of ECM proteins which secretion improved in the organotypic co-culture membrane systems. The heterotypic cell-cell contacts have beneficial effect on the hepatocyte albumin production, urea synthesis and drug biotransformation. The developed organotypic co-culture membrane systems elicit liver specific functions in vitro and could be applied for the realization of engineered liver tissues to be used in tissue engineering, drug metabolism studies and bioartificial liver devices. PMID:21871658

  18. Hepatobiliary disposition in primary cultures of dog and monkey hepatocytes.

    PubMed

    Rose, Kelly A; Kostrubsky, Vsevolod; Sahi, Jasminder

    2006-01-01

    Hepatobiliary transporters are a major route for elimination of xenobiotics and endogenous products. In vitro hepatobiliary models have been reported for human and rat, but not for the other preclinical species used in safety evaluation. We have established methodologies for culturing dog and monkey hepatocytes with optimal bile canalicular formation and function, using a sandwich culture comprising rigid collagen substratum and gelled collagen overlay. Hepatic uptake utilizing sinusoidal transporters and biliary excretion through canalicular transporters were assessed using the bile salt taurocholate, salicylate (negative control), and the Bsep inhibitors cyclosporin A (CsA) and glyburide. There was significant taurocholate and salicylate canalicular efflux in dog and monkey hepatocytes, although the amount of salicylate transported was one thousandth that of taurocholate. Species differences were observed, as glyburide significantly inhibited taurocholate uptake in monkey (64% at 10 microM) but not dog hepatocytes, and inhibited taurocholate efflux in dog (100% at 10 microM) but not monkey hepatocytes. CsA did not inhibit bile salt uptake and significantly inhibited canalicular efflux in dog (at 0.1 microM) and monkey (at 1 and 10 microM) hepatocyte cultures. These results suggest that glyburide is a bile salt uptake inhibitor in monkey but not in dog hepatocytes and that CsA inhibits bile salt canalicular efflux but not basolateral uptake in these species. We have established dog and monkey hepatocytes in sandwich culture with intact bile canalicular formation and function. The differences observed in taurocholate transport between dog and monkey hepatocytes may be indicative of in vivo species differences. PMID:16749858

  19. Generation of functional hepatocytes from human spermatogonial stem cells

    PubMed Central

    Chen, Zheng; Sun, Min; Yuan, Qingqing; Niu, Minghui; Yao, Chencheng; Hou, Jingmei; Wang, Hong; Wen, Liping; Liu, Yun; Li, Zheng; He, Zuping

    2016-01-01

    To generate functional human hepatocytes from stem cells and/or extra-hepatic tissues could provide an important source of cells for treating liver diseases. Spermatogonial stem cells (SSCs) have an unlimited plasticity since they can dedifferentiate and transdifferentiate to other cell lineages. However, generation of mature and functional hepatocytes from human SSCs has not yet been achieved. Here we have for the first time reported direct transdifferentiation of human SSCs to mature and functional hepatocytes by three-step induction using the defined condition medium. Human SSCs were first transdifferentiated to hepatic stem cells, as evidenced by their morphology and biopotential nature of co-expressing hepatocyte and cholangiocyte markers but not hallmarks for embryonic stem cells. Hepatic stem cells were further induced to differentiate into mature hepatocytes identified by their morphological traits and strong expression of CK8, CK18, ALB, AAT, TF, TAT, and cytochrome enzymes rather than CK7 or CK19. Significantly, mature hepatocytes derived from human SSCs assumed functional attributes of human hepatocytes, because they could produce albumin, remove ammonia, and uptake and release indocyanine green. Moreover, expression of β-CATENIN, HNF4A, FOXA1 and GATA4 was upregulated during the transdifferentiation of human SSCs to mature hepatocytes. Collectively, human SSCs could directly transdifferentiate to mature and functional hepatocytes. This study could offer an invaluable source of human hepatocytes for curing liver disorders and drug toxicology screening and provide novel insights into mechanisms underlying human liver regeneration. PMID:26840458

  20. Generation of functional hepatocytes from human spermatogonial stem cells.

    PubMed

    Chen, Zheng; Sun, Min; Yuan, Qingqing; Niu, Minghui; Yao, Chencheng; Hou, Jingmei; Wang, Hong; Wen, Liping; Liu, Yun; Li, Zheng; He, Zuping

    2016-02-23

    To generate functional human hepatocytes from stem cells and/or extra-hepatic tissues could provide an important source of cells for treating liver diseases. Spermatogonial stem cells (SSCs) have an unlimited plasticity since they can dedifferentiate and transdifferentiate to other cell lineages. However, generation of mature and functional hepatocytes from human SSCs has not yet been achieved. Here we have for the first time reported direct transdifferentiation of human SSCs to mature and functional hepatocytes by three-step induction using the defined condition medium. Human SSCs were first transdifferentiated to hepatic stem cells, as evidenced by their morphology and biopotential nature of co-expressing hepatocyte and cholangiocyte markers but not hallmarks for embryonic stem cells. Hepatic stem cells were further induced to differentiate into mature hepatocytes identified by their morphological traits and strong expression of CK8, CK18, ALB, AAT, TF, TAT, and cytochrome enzymes rather than CK7 or CK19. Significantly, mature hepatocytes derived from human SSCs assumed functional attributes of human hepatocytes, because they could produce albumin, remove ammonia, and uptake and release indocyanine green. Moreover, expression of β-CATENIN, HNF4A, FOXA1 and GATA4 was upregulated during the transdifferentiation of human SSCs to mature hepatocytes. Collectively, human SSCs could directly transdifferentiate to mature and functional hepatocytes. This study could offer an invaluable source of human hepatocytes for curing liver disorders and drug toxicology screening and provide novel insights into mechanisms underlying human liver regeneration. PMID:26840458

  1. A novel herbal formulation "LiverCare" differentially regulates primary rat hepatocyte and hepatocarcinoma cell proliferation in vitro.

    PubMed

    Vidyashankar, Satyakumar; Varma, Sandeep R; Azeemudin, Mohammed; Godavarthi, Ashok; Krishna, Nandakumar S; Patki, Pralhad Sadashiv

    2011-09-01

    Hepatocyte growth factor (HGF) plays an important role in hepatocyte proliferation. HGF expression is regulated by various signaling molecules and nuclear receptors. In the present study, LiverCare(®) (LC), a novel polyherbal formulation (The Himalaya Drug Company, Bangalore, India), was evaluated for its efficacy, using co-cultures of primary rat hepatocytes-non-parenchymal cells (NPCs) and human hepatocellular carcinoma cells (HepG2). The rate of primary hepatocyte co-culture proliferation was significantly and dose-dependently increased by LC as determined by [(3)H]thymidine incorporation into newly synthesized DNA and cell proliferation assay. LC also increased HGF expression in primary hepatocyte co-culture. Albumin and urea content remained constant during proliferation of hepatocyte co-cultures in the presence of LC with decreased activity of alanine aminotransferase. It is interesting that LC inhibited incorporation of [(3)H]thymidine into DNA in HepG2 cells. LC enhanced peroxisome proliferator-activated receptor-α expression during hepatocyte proliferation, whereas tumor necrosis factor-α expression remained unaffected. In conclusion, our study clearly showed that LC differentially regulates primary rat hepatocytes and human hepatocarcinoma cell proliferation. LC may be a promising candidate for treating degenerative liver diseases by enhancing liver regeneration. PMID:21812649

  2. Solubilized liver extracellular matrix maintains primary rat hepatocyte phenotype in-vitro.

    PubMed

    Loneker, Abigail E; Faulk, Denver M; Hussey, George S; D'Amore, Antonio; Badylak, Stephen F

    2016-04-01

    Whole organ engineering and cell-based regenerative medicine approaches are being investigated as potential therapeutic options for end-stage liver failure. However, a major challenge of these strategies is the loss of hepatic specific function after hepatocytes are removed from their native microenvironment. The objective of the present study was to determine if solubilized liver extracellular matrix (ECM), when used as a media supplement, can better maintain hepatocyte phenotype compared to type I collagen alone or solubilized ECM harvested from a non-liver tissue source. Liver extracellular matrix (LECM) from four different species was isolated via liver tissue decellularization, solubilized, and then used as a media supplement for primary rat hepatocytes (PRH). The four species of LECM investigated were human, porcine, canine and rat. Cell morphology, albumin secretion, and ammonia metabolism were used to assess maintenance of hepatocyte phenotype. Biochemical and mechanical characterization of each LECM were also conducted. Results showed that PRH's supplemented with canine and porcine LECM maintained their phenotype to a greater extent compared to all other groups. PRH's supplemented with canine and porcine LECM showed increased bile production, increased albumin production, and the formation of multinucleate cells. The findings of the present study suggest that solubilized liver ECM can support in-vitro hepatocyte culture and should be considered for therapeutic and diagnostic techniques that utilize hepatocytes. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 957-965, 2016. PMID:26704367

  3. Epigenetic Modifications as Antidedifferentiation Strategy for Primary Hepatocytes in Culture.

    PubMed

    Bolleyn, Jennifer; Fraczek, Joanna; Rogiers, Vera; Vanhaecke, Tamara

    2015-01-01

    A well-known problem of cultured primary hepatocytes is their rapid dedifferentiation. During the last years, several strategies to counteract this phenomenon have been developed, of which changing the in vitro environment is the most popular one. However, mimicking the in vivo setting in vitro by adding soluble media additives or the restoration of both cell-cell and cell-extracellular matrix contacts is not sufficient and only delays the dedifferentiation process instead of counteracting it. In this chapter, new strategies to prevent the deterioration of the liver-specific phenotype of primary hepatocytes in culture by targeting the (epi)genetic mechanisms that drive hepatocellular gene expression are described. PMID:26272144

  4. Evaluation of multiple mechanism-based toxicity endpoints in primary cultured human hepatocytes for the identification of drugs with clinical hepatotoxicity: Results from 152 marketed drugs with known liver injury profiles.

    PubMed

    Zhang, Jie; Doshi, Utkarsh; Suzuki, Ayako; Chang, Ching-Wei; Borlak, Jürgen; Li, Albert P; Tong, Weida

    2016-08-01

    We report here the results of a collaborative research program to develop a robust and reliable in vitro system to allow an accurate definition of the drug-induced liver injury (DILI) potential of new drug entities during drug development. The in vitro hepatotoxic potential of 152 drugs with known DILI profiles were evaluated in primary cultured human hepatocytes with four mechanistically-relevant endpoints: cellular ATP depletion, reactive oxygen species (ROS), glutathione (GSH) depletion, and caspase activation for apoptosis. The drugs, 80 in the testing set and 72 in the validation set, were classified based on serious clinical/regulatory outcomes as defined by reported acute liver failure, black-box warning, and/or withdrawal. The drugs were further sub-categorized for dominant types of liver injury. Logistic regression models were performed to calculate the area under the receiver operating characteristics curve (AUROC) and to evaluate the prediction potential of the selected endpoints for serious clinical/regulatory outcomes. The ROS/ATP ratio was found to yield an excellent AUROC in both the testing (0.8989, P < 0.0001) and validation set (0.8545, P < 0.0001), and was found to distinguish drugs associated with severe from non-severe DILI cases (p < 0.0001). The results suggest that evaluation of drugs in primary human hepatocytes using the ROS/ATP ratio endpoint may aid the definition of their potential to cause severe DILI. PMID:26581450

  5. Effect of solid freeform fabrication-based polycaprolactone/poly(lactic-co-glycolic acid)/collagen scaffolds on cellular activities of human adipose-derived stem cells and rat primary hepatocytes.

    PubMed

    Shim, Jin-Hyung; Kim, Arthur Joon; Park, Ju Young; Yi, Namwoo; Kang, Inhye; Park, Jaesung; Rhie, Jong-Won; Cho, Dong-Woo

    2013-04-01

    Highly biocompatible polycaprolactone (PCL)/poly(lactic-co-glycolic acid) (PLGA)/collagen scaffolds in which the PCL/PLGA collagen solution was selectively dispensed into every other space between the struts were fabricated using solid freeform fabrication (SFF) technology, as we described previously. The objective of this study was to evaluate and compare the PCL/PLGA/collagen scaffolds (group 3) with PCL/PLGA-only scaffolds (group 1) and PCL/PLGA scaffolds with collagen by the dip-coating method (group 2) using human adipose-derived stem cells (hASCs) and rat primary hepatocytes. The selectively dispensed collagen formed a three-dimensional (3D) network of nanofibers in group 3, as observed by scanning electron microscopy. The compressive strength and modulus of group 3 were approximately 140 and 510 times higher, respectively, than those of a sponge-type collagen scaffold whose weak mechanical properties were regarded as a critical drawback. Proliferation and osteogenic differentiation of hASCs were promoted significantly in group 3 compared to groups 1 and 2. In addition, we found that the viability and albumin secretion ability of rat primary hepatocytes were highly retained for 10 days in group 3 but not group 1. Interestingly, hepatocyte aggregation, which enhances hepatic function through cell-cell interactions, was observed particularly in group 3. In conclusion, group 3, in which the collagen was selectively dispensed in the 3D space of the porous PCL/PLGA framework, will be a promising 3D scaffold for culturing various cell types. PMID:23430333

  6. Scoparone affects lipid metabolism in primary hepatocytes using lipidomics.

    PubMed

    Zhang, Aihua; Qiu, Shi; Sun, Hui; Zhang, Tianlei; Guan, Yu; Han, Ying; Yan, Guangli; Wang, Xijun

    2016-01-01

    Lipidomics, which focuses on the global study of molecular lipids in biological systems, could provide valuable insights about disease mechanisms. In this study, we present a nontargeted lipidomics strategy to determine cellular lipid alterations after scoparone exposure in primary hepatocytes. Lipid metabolic profiles were analyzed by high-performance liquid chromatography coupled with time-of-flight mass spectrometry, and a novel imaging TransOmics tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. Chemometric and statistical analyses of the obtained lipid fingerprints revealed the global lipidomic alterations and tested the therapeutic effects of scoparone. Identification of ten proposed lipids contributed to the better understanding of the effects of scoparone on lipid metabolism in hepatocytes. The most striking finding was that scoparone caused comprehensive lipid changes, as represented by significant changes of the identificated lipids. The levels of identified PG(19:1(9Z)/14:0), PE(17:1(9Z)/0:0), PE(19:1(9Z)/0:0) were found to be upregulated in ethanol-induced group, whereas the levels in scoparone group were downregulated. Lipid metabolism in primary hepatocytes was changed significantly by scoparone treatment. We believe that this novel approach could substantially broaden the applications of high mass resolution mass spectrometry for cellular lipidomics. PMID:27306123

  7. Scoparone affects lipid metabolism in primary hepatocytes using lipidomics

    PubMed Central

    Zhang, Aihua; Qiu, Shi; Sun, Hui; Zhang, Tianlei; Guan, Yu; Han, Ying; Yan, Guangli; Wang, Xijun

    2016-01-01

    Lipidomics, which focuses on the global study of molecular lipids in biological systems, could provide valuable insights about disease mechanisms. In this study, we present a nontargeted lipidomics strategy to determine cellular lipid alterations after scoparone exposure in primary hepatocytes. Lipid metabolic profiles were analyzed by high-performance liquid chromatography coupled with time-of-flight mass spectrometry, and a novel imaging TransOmics tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. Chemometric and statistical analyses of the obtained lipid fingerprints revealed the global lipidomic alterations and tested the therapeutic effects of scoparone. Identification of ten proposed lipids contributed to the better understanding of the effects of scoparone on lipid metabolism in hepatocytes. The most striking finding was that scoparone caused comprehensive lipid changes, as represented by significant changes of the identificated lipids. The levels of identified PG(19:1(9Z)/14:0), PE(17:1(9Z)/0:0), PE(19:1(9Z)/0:0) were found to be upregulated in ethanol-induced group, whereas the levels in scoparone group were downregulated. Lipid metabolism in primary hepatocytes was changed significantly by scoparone treatment. We believe that this novel approach could substantially broaden the applications of high mass resolution mass spectrometry for cellular lipidomics. PMID:27306123

  8. Modeling of Hepatocytes Proliferation Isolated from Proximal and Distal Zones from Human Hepatocellular Carcinoma Lesion

    PubMed Central

    Montalbano, Mauro; Curcurù, Giuseppe; Shirafkan, Ali; Vento, Renza; Rastellini, Cristiana; Cicalese, Luca

    2016-01-01

    Isolation of hepatocytes from cirrhotic human livers and subsequent primary culture are important new tools for laboratory research and cell-based therapeutics in the study of hepatocellular carcinoma (HCC). Using such techniques, we have previously identified different subpopulations of human hepatocytes and among them one is showing a progressive transformation of hepatocytes in HCC-like cells. We have hypothesized that increasing the distance from the neoplastic lesion might affect hepatocyte function and transformation capacity. However, limited information is available in comparing the growth and proliferation of human hepatocytes obtained from different areas of the same cirrhotic liver in relation to their distance from the HCC lesion. In this study, hepatocytes from 10 patients with cirrhosis and HCC undergoing surgical resections from specimens obtained at a proximal (CP) and distal (CD) distance from the HCC lesion were isolated and placed in primary culture. CP hepatocytes (CP-Hep) were isolated between 1 to 3 cm (leaving at least 1cm margin to avoid cancer cells and/or satellite lesions), while CD hepatocytes (CD-Hep) were isolated from more than 5 cm or from the contralateral-lobe. A statistical model was built to analyze the proliferation rates of these cells and we evaluated expression of HCC markers (Glypican-3 (GPC3), αSmooth Muscle Actin (α-SMA) and PCNA). We observed a significant difference in proliferation and in-vitro growth showing that CP-Hep had a proliferation pattern and rate significantly different than CD-Hep. Based on these data, this model can provide information to predict growth of human hepatocytes in primary culture in relation to their pre-cancerous state with significant differences in the HCC markers expression. This model provides an important innovative tool for in-vitro analysis of HCC. PMID:27074018

  9. Human and rat primary hepatocyte CYP1A1 and 1A2 induction with 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and 2,3,4,7,8-pentachlorodibenzofuran.

    PubMed

    Budinsky, Robert A; LeCluyse, Edward L; Ferguson, Stephen S; Rowlands, J Craig; Simon, Ted

    2010-11-01

    The concentration dose response for aryl hydrocarbon receptor (AHR)-mediated CYP1A1 and CYP1A2 messenger RNA (mRNA) induction and enzyme activity was determined in primary cultures of rat and human hepatocytes for 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,4,7,8-pentachlorodibenzofuran, and 2,3,7,8-tetrachlorodibenzofuran. Eleven different congener concentrations from 0.00001 to 100 nM were used, thus spanning seven orders of magnitude. The Hill model was used to obtain values of EC(x) and maximal response from the individual data sets. No-observed effect concentration values were derived using several statistical methods including Dunnett's test, the Welch-Aspin test, and step-down bilinear regression. Thresholds were estimated using baseline projection methods and a "hockey stick" fitting method. Human hepatocytes were less responsive and less sensitive with respect to CYP1A1 activity and mRNA induction than rats. On the other hand, the human CYP1A2 response was more robust than the response in rats but generally less sensitive. These data allow an evaluation of relative species sensitivities for developing interspecies toxicodynamic adjustment factors, for assessing AHR activation thresholds, and for evaluating relative congener potencies. Overall, these data support the position that humans are less sensitive than rats to these AHR-dependent end points and support the use of a data-derived adjustment factor of 1.0 or less for extrapolating between rats and humans. PMID:20705892

  10. Improved cryopreservation of human hepatocytes using a new xeno free cryoprotectant solution

    PubMed Central

    Saliem, Mohammed; Holm, Frida; Tengzelius, Rosita Bergström; Jorns, Carl; Nilsson, Lisa-Mari; Ericzon, Bo-Göran; Ellis, Ewa; Hovatta, Outi

    2012-01-01

    AIM: To optimize a xeno-free cryopreservation protocol for primary human hepatocytes. METHODS: The demand for cryopreserved hepatocytes is increasing for both clinical and research purposes. Despite several hepatocyte cryopreservation protocols being available, improvements are urgently needed. We first compared controlled rate freezing to polystyrene box freezing and did not find any significant change between the groups. Using the polystyrene box freezing, we compared two xeno-free freezing solutions for freezing of primary human hepatocytes: a new medium (STEM-CELLBANKER, CB), which contains dimethylsulphoxide (DMSO) and anhydrous dextrose, both permeating and non-permeating cryoprotectants, and the frequently used DMSO - University of Wisconsin (DMSO-UW) medium. The viability of the hepatocytes was assessed by the trypan blue exclusion method as well as a calcein-esterase based live-dead assay before and after cryopreservation. The function of the hepatocytes was evaluated before and after cryopreservation by assessing enzymatic activity of 6 major cytochrome P450 isoforms (CYPs): CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A4 and CYP3A7. RESULTS: The new cryoprotectant combination preserved hepatocyte viability significantly better than the standard DMSO-UW protocol (P < 0.01). There was no significant difference in viability estimation between both the trypan blue (TB) and the Live-Dead Assay methods. There was a correlation between viability of fresh hepatocytes and the difference in cell viability between CB and DMSO protocols (r2 = 0.69) using the TB method. However, due to high within-group variability in the activities of the major CYPs, any statistical between-group differences were precluded. Cryopreservation of human hepatocytes using the cryoprotectant combination was a simple and xeno-free procedure yielding better hepatocyte viability. Thus, it may be a better alternative to the standard DMSO-UW protocol. Estimating CYP activities did not seem to be a

  11. Generation of proliferating human hepatocytes using Upcyte® technology: characterisation and applications in induction and cytotoxicity assays.

    PubMed

    Burkard, Alexandra; Dähn, Caroline; Heinz, Stefan; Zutavern, Anne; Sonntag-Buck, Vera; Maltman, Daniel; Przyborski, Stefan; Hewitt, Nicola J; Braspenning, Joris

    2012-10-01

    1. We have developed a novel technique which causes primary human hepatocytes to proliferate by transducing them with genes that upregulate their proliferation. 2. Upcyte(®) hepatocytes did not form colonies in soft agar and are not immortalised anchorage-independent cells. Confluent cultures expressed liver-specific proteins, produced urea and stored glycogen. 3. CYP activities were low but similar to that in 5-day cultures of primary human hepatocytes. CYP1A2 and CYP3A4 were inducible; moreover, upcyte(®) hepatocytes predicted the in vivo induction potencies of known CYP3A4 inducers using the "relative induction score" prediction model. Placing cells into 3D culture increased their basal CYP2B6 and CYP3A4 basal activities and induction responses. 4. Phase 2 activities (UGTs, SULTs and GSTs) were comparable to activities in freshly isolated hepatocytes. 5. Upcyte(®) hepatocytes were markedly more sensitive to the hepatotoxin, α-amanitin, than HepG2 cells, indicating functional OATP1B3 uptake. The cytotoxicity of aflatoxin B(1), was decreased in upcyte(®) hepatocytes by co-incubation with the CYP3A4 inhibitor, ketoconazole. Upcyte(®) hepatocytes also differentiated between ten hepatotoxic and eight non-hepatotoxic compounds. 6. In conclusion, upcyte(®) hepatocyte cultures have a differentiated phenotype and exhibit functional phase 1 and 2 activities. These data support the use of upcyte(®) hepatocytes for CYP induction and cytotoxicity screening. PMID:22524704

  12. 5α-Reductase Type 2 Regulates Glucocorticoid Action and Metabolic Phenotype in Human Hepatocytes.

    PubMed

    Nasiri, Maryam; Nikolaou, Nikolaos; Parajes, Silvia; Krone, Nils P; Valsamakis, George; Mastorakos, George; Hughes, Beverly; Taylor, Angela; Bujalska, Iwona J; Gathercole, Laura L; Tomlinson, Jeremy W

    2015-08-01

    Glucocorticoids and androgens have both been implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD); androgen deficiency in males, androgen excess in females, and glucocorticoid excess in both sexes are associated with NAFLD. Glucocorticoid and androgen action are regulated at a prereceptor level by the enzyme 5α-reductase type 2 (SRD5A2), which inactivates glucocorticoids to their dihydrometabolites and converts T to DHT. We have therefore explored the role of androgens and glucocorticoids and their metabolism by SRD5A2 upon lipid homeostasis in human hepatocytes. In both primary human hepatocytes and human hepatoma cell lines, glucocorticoids decreased de novo lipogenesis in a dose-dependent manner. Whereas androgen treatment (T and DHT) increased lipogenesis in cell lines and in primary cultures of human hepatocytes from female donors, it was without effect in primary hepatocyte cultures from men. SRD5A2 overexpression reduced the effects of cortisol to suppress lipogenesis and this effect was lost following transfection with an inactive mutant construct. Conversely, pharmacological inhibition using the 5α-reductase inhibitors finasteride and dutasteride augmented cortisol action. We have demonstrated that manipulation of SRD5A2 activity can regulate lipogenesis in human hepatocytes in vitro. This may have significant clinical implications for those patients prescribed 5α-reductase inhibitors, in particular augmenting the actions of glucocorticoids to modulate hepatic lipid flux. PMID:25974403

  13. 5α-Reductase Type 2 Regulates Glucocorticoid Action and Metabolic Phenotype in Human Hepatocytes

    PubMed Central

    Nasiri, Maryam; Nikolaou, Nikolaos; Parajes, Silvia; Krone, Nils P.; Valsamakis, George; Mastorakos, George; Hughes, Beverly; Taylor, Angela; Bujalska, Iwona J.; Gathercole, Laura L.

    2015-01-01

    Glucocorticoids and androgens have both been implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD); androgen deficiency in males, androgen excess in females, and glucocorticoid excess in both sexes are associated with NAFLD. Glucocorticoid and androgen action are regulated at a prereceptor level by the enzyme 5α-reductase type 2 (SRD5A2), which inactivates glucocorticoids to their dihydrometabolites and converts T to DHT. We have therefore explored the role of androgens and glucocorticoids and their metabolism by SRD5A2 upon lipid homeostasis in human hepatocytes. In both primary human hepatocytes and human hepatoma cell lines, glucocorticoids decreased de novo lipogenesis in a dose-dependent manner. Whereas androgen treatment (T and DHT) increased lipogenesis in cell lines and in primary cultures of human hepatocytes from female donors, it was without effect in primary hepatocyte cultures from men. SRD5A2 overexpression reduced the effects of cortisol to suppress lipogenesis and this effect was lost following transfection with an inactive mutant construct. Conversely, pharmacological inhibition using the 5α-reductase inhibitors finasteride and dutasteride augmented cortisol action. We have demonstrated that manipulation of SRD5A2 activity can regulate lipogenesis in human hepatocytes in vitro. This may have significant clinical implications for those patients prescribed 5α-reductase inhibitors, in particular augmenting the actions of glucocorticoids to modulate hepatic lipid flux. PMID:25974403

  14. Highly Efficient Differentiation of Functional Hepatocytes From Human Induced Pluripotent Stem Cells

    PubMed Central

    Ma, Xiaocui; Tschudy-Seney, Benjamin; Roll, Garrett; Behbahan, Iman Saramipoor; Ahuja, Tijess P.; Tolstikov, Vladimir; Wang, Charles; McGee, Jeannine; Khoobyari, Shiva; Nolta, Jan A.; Willenbring, Holger

    2013-01-01

    Human induced pluripotent stem cells (hiPSCs) hold great potential for use in regenerative medicine, novel drug development, and disease progression/developmental studies. Here, we report highly efficient differentiation of hiPSCs toward a relatively homogeneous population of functional hepatocytes. hiPSC-derived hepatocytes (hiHs) not only showed a high expression of hepatocyte-specific proteins and liver-specific functions, but they also developed a functional biotransformation system including phase I and II metabolizing enzymes and phase III transporters. Nuclear receptors, which are critical for regulating the expression of metabolizing enzymes, were also expressed in hiHs. hiHs also responded to different compounds/inducers of cytochrome P450 as mature hepatocytes do. To follow up on this observation, we analyzed the drug metabolizing capacity of hiHs in real time using a novel ultraperformance liquid chromatography-tandem mass spectrometry. We found that, like freshly isolated primary human hepatocytes, the seven major metabolic pathways of the drug bufuralol were found in hiHs. In addition, transplanted hiHs engrafted, integrated, and proliferated in livers of an immune-deficient mouse model, and secreted human albumin, indicating that hiHs also function in vivo. In conclusion, we have generated a method for the efficient generation of hepatocytes from induced pluripotent stem cells in vitro and in vivo, and it appears that the cells function similarly to primary human hepatocytes, including developing a complete metabolic function. These results represent a significant step toward using patient/disease-specific hepatocytes for cell-based therapeutics as well as for pharmacology and toxicology studies. PMID:23681950

  15. Thyroid hormone effect in human hepatocytes.

    PubMed

    Miler, Eliana A; Ríos de Molina, María Del Carmen; Domínguez, Gabriela; Guerra, Liliana N

    2008-01-01

    We have already demonstrated that a combined treatment of methimazole and an antioxidant mixture improved the condition of hyperthyroid patients both biochemically and clinically. Elevated thyroid hormone levels might trigger signs and symptoms of hyperthyroidism through the increase of free radicals. To study the direct effect of thyroid hormone on cellular markers of oxidative stress, we carried out in vitro assays in which 0.1-20.0 nM T3 (6.5-1300.0 ng/dl) doses were added to culture media of the human hepatocyte cell line Hep G2 for 1-24 h. T3 increased malondialdehyde (MDA) and intracellular oxidized glutathione (GSSG) levels; SOD activity was also higher with hormone treatment, whereas catalase and glutathione peroxidase activities showed no variation at different T3 doses and during all experimental times. When ascorbic acid was added to the culture, the MDA level decreased and SOD activity was increased. With higher doses of T3 (e.g. 200 nM), cell death occurred (69% of apoptotic cells). The increase in SOD activity was not enough to overcome the effect of T3 since MDA and GSSG remained high during a 24-h experiment. We showed a beneficial effect of ascorbic acid when cells were exposed to a T3 dose of 20 nM, a higher level of hormone than that achieved in hyperthyroidism. PMID:18647489

  16. Primary rat hepatocytes in chemical testing and QSAR predictive applicability.

    PubMed

    Tichý, Milon; Pokorná, Adéla; Hanzlíková, Iveta; Nerudová, Jana; Tumová, Jana; Uzlová, Rút

    2010-02-01

    Primary rat hepatocytes were used to test acute toxicities of 16 neutral aliphatic alcohols, ketones and esters. Their effects on cell viability and metabolic function (ureogenesis, i.e. biotransformation of ornithine to urea) were measured and expressed as EC50 values. Log EC50 values from both tests correlated with the log partition coefficients for the chemicals between n-octanol and water and log P(ow)-based QSAR models were derived. Log EC50 (viability) tightly correlates with log EC50 (ureogenesis): log EC50 (viability)=0.91 log EC50 (ureogenesis)+0.06. Each of these toxic indices can be substituted by the other one. The toxic indices for both cell viability and metabolic disorder can be estimated using log EC50 for movement inhibition in the oligochaete Tubifex tubifex and the respective QSAR equation. It eliminates a usage of rats. Their correlations were proved and justified. PMID:19735719

  17. Uptake and processing of human platelet factor 4 by hepatocytes

    SciTech Connect

    Rucinski, B.; Steward, G.J.; de Feo, P.A.; Boden, G.; Niewiarowski, S.

    1987-12-01

    We previously demonstrated rapid clearance of human platelet factor 4 (PF4) from rabbit and rat blood, its accumulation in the liver, and elimination of PF4 degradation products in urine. The purpose of the present experiments was to characterize interaction of PF4 with cultured rat hepatocytes. /sup 125/I-PF4 was taken up by hepatocytes reaching maximum at 180 min. The association of /sup 125/I-PF4 with hepatocytes was two times greater at 37/sup 0/C than at 4/sup 0/C. At 37/sup 0/C degradation of /sup 125/-PF4 by hepatocytes was also observed as indicated by the increase of /sup 125/I-PF4 radioactivity soluble in 6% trichloroacetic acid. By contrast, no uptake of /sup 125/I-..beta..-thromboglobulin antigen was observed. Autoradiography demonstrated that short incubation (5-20 min) of /sup 125/I-PF4 with hepatocytes results in the association of /sup 125/I-radioactivity with cell membranes while after longer incubation (60 min) radioactivity was also localized in the endosomes. Heparin inhibited binding and uptake of /sup 125/I-PF4 radioactivity by hepatocytes. We propose that part of PF4 released in the circulating blood by activated platelets is bound to the surface of hepatocytes and that it is further processed by these cells.

  18. Cryopreserved human hepatocytes as alternative in vitro model for cytochrome p450 induction studies.

    PubMed

    Garcia, Martha; Rager, Joseph; Wang, Qing; Strab, Robert; Hidalgo, Ismael J; Owen, Albert; Li, Jibin

    2003-01-01

    Induction of cytochrome P450 (CYP) by drugs is one of major concerns for drug-drug interactions. Thus, the assessment of CYP induction by novel compounds is a vital component in the drug discovery and development processes. Primary human hepatocytes are the preferred in vitro model for predicting CYP induction in vivo. However, their use is hampered by the erratic supply of human tissue and donor-to-donor variability. Although cryopreserved hepatocytes have been recommended for short-term applications in suspension, their use in studies on induction of enzyme activity has been limited because of poor attachment and response to enzyme inducers. In this study, we report culture conditions that allowed the attachment of cryopreserved human hepatocytes and responsiveness to CYP inducers. We evaluated the inducibility of CYP1A1/2 and CYP3A4 enzymes in cryopreserved hepatocytes from three human donors. Cryopreserved human hepatocytes were cultured in serum-free medium for 4 d. They exhibited normal morphology and measurable viability as evaluated by the reduction of tetrazolium salts (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt) by cellular dehydrogenases. Treatment with beta-naphthoflavone (10 microM) for 3 d increased ethoxyresorufin-O-deethylase activity (CYP1A1/2) by 6- to 11-fold over untreated cultures and increased CYP1A2 messenger ribonucleic acid (mRNA) expression by three- to eightfold. Similarly, treatment of cryopreserved human hepatocytes with rifampicin (25 microM) for 3 d increased testosterone 6 beta-hydroxylase activity (CYP3A4) by five- to eightfold over untreated cultures and increased CYP3A4 mRNA expression by four- to eightfold. The results suggest that cryopreserved human hepatocytes can be a suitable in vitro model for evaluating xenobiotics as inducers of CYP1A1/2 and CYP3A4 enzymes. PMID:14599235

  19. Effect of Concentrated Fibroblast-Conditioned Media on In Vitro Maintenance of Rat Primary Hepatocyte

    PubMed Central

    Jeong, Dayeong; Han, Chungmin; Kang, Inhye; Park, Hyun Taek; Kim, Jiyoon; Ryu, Hayoung; Gho, Yong Song; Park, Jaesung

    2016-01-01

    The effects of concentrated fibroblast-conditioned media were tested to determine whether hepatocyte function can be maintained without direct contact between hepatocytes and fibroblasts. Primary rat hepatocytes cultured with a concentrated conditioned media of NIH-3T3 J2 cell line (final concentration of 55 mg/ml) showed significantly improved survival and functions (albumin and urea) compared to those of control groups. They also showed higher expression levels of mRNA, albumin and tyrosine aminotransferase compared to hepatocyte monoculture. The results suggest that culture with concentrated fibroblast-conditioned media could be an easy method for in vitro maintenance of primary hepatocytes. They also could be contribute to understand and analyze co-culture condition of hepatocyte with stroma cells. PMID:26863621

  20. PURIFICATION AND BIOLOGICAL CHARACTERIZATION OF HUMAN HEPATOPOETIN A: A POLYPEPTIDE GROWTH FACTOR FOR HEPATOCYTES

    EPA Science Inventory

    We have previously reported that the presence of a high molecular weight polypeptide growth factor in the plasma of normal human or rat serum which stimulates DNA synthesis in primary cultures of normal rat hepatocytes. e referred to this activity as Hepatopoietin A (HPTA) (6,7)....

  1. Towards liver-directed gene therapy: retrovirus-mediated gene transfer into human hepatocytes.

    PubMed

    Grossman, M; Raper, S E; Wilson, J M

    1991-11-01

    Liver-directed gene therapy is being considered in the treatment of inherited metabolic diseases. One approach we are considering is the transplantation of autologous hepatocytes that have been genetically modified with recombinant retroviruses ex vivo. We describe, in this report, techniques for isolating human hepatocytes and efficiently transducing recombinant genes into primary cultures. Hepatocytes were isolated from tissue of four different donors, plated in primary culture, and exposed to recombinant retroviruses expressing either the LacZ reporter gene or the cDNA for rabbit LDL receptor. The efficiency of gene transfer under optimal conditions, as determined by Southern blot analysis, varied from a maximum of one proviral copy per cell to a minimum of 0.1 proviral copy per cell. Cytochemical assays were used to detect expression of the recombinant derived proteins, E. coli beta-galactosidase and rabbit LDL receptor. Hepatocytes transduced with the LDL receptor gene expressed levels of receptor protein that exceeded the normal endogenous levels. The ability to isolate and genetically modify human hepatocytes, as described in this report, is an important step towards the development of liver-directed gene therapies in humans. PMID:1767337

  2. Human hepatocytes derived from pluripotent stem cells: a promising cell model for drug hepatotoxicity screening.

    PubMed

    Gómez-Lechón, María José; Tolosa, Laia

    2016-09-01

    Drug-induced liver injury (DILI) is a frequent cause of failure in both clinical and post-approval stages of drug development, and poses a key challenge to the pharmaceutical industry. Current animal models offer poor prediction of human DILI. Although several human cell-based models have been proposed for the detection of human DILI, human primary hepatocytes remain the gold standard for preclinical toxicological screening. However, their use is hindered by their limited availability, variability and phenotypic instability. In contrast, pluripotent stem cells, which include embryonic and induced pluripotent stem cells (iPSCs), proliferate extensively in vitro and can be differentiated into hepatocytes by the addition of soluble factors. This provides a stable source of hepatocytes for multiple applications, including early preclinical hepatotoxicity screening. In addition, iPSCs also have the potential to establish genotype-specific cells from different individuals, which would increase the predictivity of toxicity assays allowing more successful clinical trials. Therefore, the generation of human hepatocyte-like cells derived from pluripotent stem cells seems to be promising for overcoming limitations of hepatocyte preparations, and it is expected to have a substantial repercussion in preclinical hepatotoxicity risk assessment in early drug development stages. PMID:27325232

  3. Lab on a chip-based hepatic sinusoidal system simulator for optimal primary hepatocyte culture.

    PubMed

    Choi, Yoon Young; Kim, Jaehyung; Lee, Sang-Hoon; Kim, Dong-Sik

    2016-08-01

    Primary hepatocyte cultures have been used in studies on liver disease, physiology, and pharmacology. While they are an important tool for in vitro liver studies, maintaining liver-specific characteristics of hepatocytes in vitro is difficult, as these cells rapidly lose their unique characteristics and functions. Portal flow is an important condition to preserve primary hepatocyte functions and liver regeneration in vivo. We have developed a microfluidic chip that does not require bulky peripheral devices or an external power source to investigate the relationship between hepatocyte functional maintenance and flow rates. In our culture system, two types of microfluidic devices were used as scaffolds: a monolayer- and a concave chamber-based device. Under flow conditions, our chips improved albumin and urea secretion rates after 13 days compared to that of the static chips. Reverse transcription polymerase chain reaction demonstrated that hepatocyte-specific gene expression was significantly higher at 13 days under flow conditions than when using static chips. For both two-dimensional and three-dimensional culture on the chips, flow resulted in the best performance of the hepatocyte culture in vitro. We demonstrated that flow improves the viability and efficiency of long-term culture of primary hepatocytes and plays a key role in hepatocyte function. These results suggest that this flow system has the potential for long-term hepatocyte cultures as well as a technique for three-dimensional culture. PMID:27334878

  4. Hepatocyte Growth Factor Reduces Free Cholesterol-Mediated Lipotoxicity in Primary Hepatocytes by Countering Oxidative Stress

    PubMed Central

    Domínguez-Pérez, Mayra; Nuño-Lámbarri, Natalia; Clavijo-Cornejo, Denise; Luna-López, Armando; Souza, Verónica; Bucio, Leticia; Miranda, Roxana U.; Muñoz, Linda; Gomez-Quiroz, Luis Enrique; Uribe-Carvajal, Salvador; Gutiérrez-Ruiz, María Concepción

    2016-01-01

    Cholesterol overload in the liver has shown toxic effects by inducing the aggravation of nonalcoholic fatty liver disease to steatohepatitis and sensitizing to damage. Although the mechanism of damage is complex, it has been demonstrated that oxidative stress plays a prominent role in the process. In addition, we have proved that hepatocyte growth factor induces an antioxidant response in hepatic cells; in the present work we aimed to figure out the protective effect of this growth factor in hepatocytes overloaded with free cholesterol. Hepatocytes from mice fed with a high-cholesterol diet were treated or not with HGF, reactive oxygen species present in cholesterol overloaded hepatocytes significantly decreased, and this effect was particularly associated with the increase in glutathione and related enzymes, such as γ-gamma glutamyl cysteine synthetase, GSH peroxidase, and GSH-S-transferase. Our data clearly indicate that HGF displays an antioxidant response by inducing the glutathione-related protection system. PMID:27143995

  5. Vascularized subcutaneous human liver tissue from engineered hepatocyte/fibroblast sheets in mice.

    PubMed

    Sakai, Yusuke; Yamanouchi, Kosho; Ohashi, Kazuo; Koike, Makiko; Utoh, Rie; Hasegawa, Hideko; Muraoka, Izumi; Suematsu, Takashi; Soyama, Akihiko; Hidaka, Masaaki; Takatsuki, Mitsuhisa; Kuroki, Tamotsu; Eguchi, Susumu

    2015-10-01

    Subcutaneous liver tissue engineering is an attractive and minimally invasive approach used to curative treat hepatic failure and inherited liver diseases. However, graft failure occurs frequently due to insufficient infiltration of blood vessels (neoangiogenesis), while the maintenance of hepatocyte phenotype and function requires in vivo development of the complex cellular organization of the hepatic lobule. Here we describe a subcutaneous human liver construction allowing for rapidly vascularized grafts by transplanting engineered cellular sheets consisting of human primary hepatocytes adhered onto a fibroblast layer. The engineered hepatocyte/fibroblast sheets (EHFSs) showed superior expression levels of vascularization-associated growth factors (vascular endothelial growth factor, transforming growth factor beta 1, and hepatocyte growth factor) in vitro. EHFSs developed into vascularized subcutaneous human liver tissues contained glycogen stores, synthesized coagulation factor IX, and showed significantly higher synthesis rates of liver-specific proteins (albumin and alpha 1 anti-trypsin) in vivo than tissues from hepatocyte-only sheets. The present study describes a new approach for vascularized human liver organogenesis under mouse skin. This approach could prove valuable for establishing novel cell therapies for liver diseases. PMID:26142777

  6. Characterization of Liver-Specific Functions of Human Fetal Hepatocytes in Culture.

    PubMed

    Chinnici, Cinzia Maria; Timoneri, Francesca; Amico, Giandomenico; Pietrosi, Giada; Vizzini, Giovanni; Spada, Marco; Pagano, Duilio; Gridelli, Bruno; Conaldi, Pier Giulio

    2015-01-01

    This study was designed to assess liver-specific functions of human fetal liver cells proposed as a potential source for hepatocyte transplantation. Fetal liver cells were isolated from livers of different gestational ages (16-22 weeks), and the functions of cell preparations were evaluated by establishing primary cultures. We observed that 20- to 22-week-gestation fetal liver cell cultures contained a predominance of cells with hepatocytic traits that did not divide in vitro but were functionally competent. Fetal hepatocytes performed liver-specific functions at levels comparable to those of their adult counterpart. Moreover, exposure to dexamethasone in combination with oncostatin M promptly induced further maturation of the cells through the acquisition of additional functions (i.e., ability to store glycogen and uptake of indocyanine green). In some cases, particularly in cultures obtained from fetuses of earlier gestational ages (16-18 weeks gestation), cells with mature hepatocytic traits proved to be sporadic, and the primary cultures were mainly populated by clusters of proliferating cells. Consequently, the values of liver-specific functions detected in these cultures were low. We observed that a low cell density culture system rapidly prompted loss of the mature hepatocytic phenotype with downregulations of all the liver-specific functions. We found that human fetal liver cells can be cryopreserved without significant loss of viability and function and evaluated up to 1 year in storage in liquid nitrogen. They might, therefore, be suitable for cell banking and allow for the transplantation of large numbers of cells, thus improving clinical outcomes. Overall, our results indicate that fetal hepatocytes could be used as a cell source for hepatocyte transplantation. Fetal liver cells have been used so far to treat end-stage liver disease. Additional studies are needed to include these cells in cell-based therapies aimed to treat liver failure and inborn

  7. Allicin Modulates the Antioxidation and Detoxification Capabilities of Primary Rat Hepatocytes

    PubMed Central

    Wu, Chih-Chung; Chu, Yung-Lin; Sheen, Lee-Yan

    2012-01-01

    The effect of allicin, an active ingredient of garlic, on lactate dehydrogenase (LDH) leakage, lipid peroxidation, glutathione (GSH) content, and GSH-related enzyme activity was investigated in primary hepatocytes. In this study, allicin was synthesized in our laboratory as an experimental material, and primary hepatocytes isolated from Sprague-Dawley rats were used as an experimental model. According to the results, hepatocytes treated with 10 μM allicin did not differ from the control on LDH leakage during various incubation times. When the hepatocytes were treated with 10 μM allicin, their levels of thiobarbituric acid reactive-substances (TBARS) did not differ significantly from that of the control within the 8-h incubation. However, the TBARS values of hepatocytes treated with 30 and 50 μM allicin were higher compared to the control after incubation for 4 h and 8 h, respectively. The hepatocyte intracellular GSH content was significantly higher than that of the control after 30 μM allicin treatment, but treatment with 50 μM allicin caused a significant GSH depletion after incubation for 4 h or longer. In addition, when hepatocytes were treated for 24 h with 10 or 30 μM allicin, glutathione peroxidase (GPx) activity was significantly increased compared to that of the control, whereas 50 μM allicin treatment for 24 h or longer significantly decreased the GPx activity. Glutathione reductase (GRd) activity was significantly increased when the hepatocytes were treated with 10 μM allicin for 24 h, but GRd activity significantly decreased when the hepatocytes were treated with 50 μM allicin. However, hepatocytes treated for 24 h with 10 or 30 μM allicin showed significantly increased glutathione S-transferase (GST) activity compared to the control. These results suggest that 10 μM allicin potentially enhances the antioxidation and detoxification capabilities of primary rat hepatocytes. PMID:24716147

  8. Comparative Transcriptomic Analysis of Primary Duck Hepatocytes Provides Insight into Differential Susceptibility to DHBV Infection

    PubMed Central

    Liu, Gang; Liu, Lei; Yu, Yao; Ding, Guohui; Zhao, Yanfeng; Li, Yixue; Xie, Youhua; Zhang, Junqi; Qu, Di

    2016-01-01

    Primary duck hepatocytes (PDH) displays differential susceptibility to duck hepatitis B virus when maintained in the media supplemented with fetal bovine serum or dimethyl sulfoxide (DMSO) which has been widely used for the maintenance of hepatocytes, and prolonging susceptibility to hepadnavirus. However the mechanism underlying maintenance of susceptibility to hepadnavirus by DMSO treatment remains unclear. In this study, a global transcriptome analysis of PDHs under different culture conditions was conducted for investigating the effects of DMSO on maintenance of susceptibility of PDH to DHBV in vitro. The 384 differential expressed genes (DEGs) were identified by comparisons between each library pair (PDHs cultured with or without DMSO or fresh isolated PDH). We analyzed canonical pathways in which the DEGs were enriched in Hepatic Fibrosis / Hepatic Stellate Cell Activation, Bile Acid Biosynthesis and Tight Junction signaling. After re-annotation against human genome data, the 384 DEGs were pooled together with proteins belonging to hepatitis B pathway to construct a protein-protein interaction network. The combination of decreased expression of liver-specific genes (CYP3A4, CYP1E1, CFI, RELN and GSTA1 et al) with increased expression of hepatocyte-dedifferentiation-associated genes (PLA2G4A and PLCG1) suggested that in vitro culture conditions results in the fading of hepatocyte phenotype in PDHs. The expression of seven DEGs associated with tight junction formation (JAM3, PPP2R2B, PRKAR1B, PPP2R2C, MAGI2, ACTA2 and ACTG2) was up-regulated after short-term culture in vitro, which was attenuated in the presence of DMSO. Those results could shed light on DHBV infection associated molecular events affected by DMSO. PMID:26900848

  9. Cholesterol Enhances the Toxic Effect of Ethanol and Acetaldehyde in Primary Mouse Hepatocytes

    PubMed Central

    López-Islas, Anayelly; Chagoya-Hazas, Victoria; Pérez-Aguilar, Benjamin; Palestino-Domínguez, Mayrel; Souza, Verónica; Miranda, Roxana U.; Bucio, Leticia; Gómez-Quiroz, Luis Enrique; Gutiérrez-Ruiz, María-Concepción

    2016-01-01

    Obesity and alcohol consumption are risk factors for hepatic steatosis, and both commonly coexist. Our objective was to evaluate the effect of ethanol and acetaldehyde on primary hepatocytes obtained from mice fed for two days with a high cholesterol (HC) diet. HC hepatocytes increased lipid and cholesterol content. HC diet sensitized hepatocytes to the toxic effect of ethanol and acetaldehyde. Cyp2E1 content increased with HC diet, as well as in those treated with ethanol or acetaldehyde, while the activity of this enzyme determined in microsomes increased in the HC and in all ethanol treated hepatocytes, HC and CW. Oxidized proteins were increased in the HC cultures treated or not with the toxins. Transmission electron microscopy showed endoplasmic reticulum (ER) stress and megamitochondria in hepatocytes treated with ethanol as in HC and the ethanol HC treated hepatocytes. ER stress determined by PERK content was increased in ethanol treated hepatocytes from HC mice and CW. Nuclear translocation of ATF6 was observed in HC hepatocytes treated with ethanol, results that indicate that lipids overload and ethanol treatment favor ER stress. Oxidative stress, ER stress, and mitochondrial damage underlie potential mechanisms for increased damage in steatotic hepatocyte treated with ethanol. PMID:26788255

  10. Role of Tribbles Pseudokinase 1 (TRIB1) in human hepatocyte metabolism.

    PubMed

    Soubeyrand, Sébastien; Martinuk, Amy; Naing, Thet; Lau, Paulina; McPherson, Ruth

    2016-02-01

    Genome-wide association studies for plasma triglycerides and hepatic steatosis identified a risk locus on chromosome 8q24 close to the TRIB1 gene, encoding Tribbles Pseudokinase 1 (TRIB1). In previous studies conducted in murine models, hepatic over-expression of Trib1 was shown to increase fatty acid oxidation and decrease triglyceride synthesis whereas Trib1 knockdown mice exhibited hypertriglyceridemia. Here we have examined the impact of TRIB1 suppression in human and mouse hepatocytes. Examination of a panel of lipid regulator transcripts revealed species-specific effects, prompting us to focus on human models for the remainder of the study. Acute knockdown of TRIB1 in human primary hepatocytes resulted in decreased expression of MTTP and APOB, required for very low density lipoprotein (VLDL) assembly although particle secretion was not significantly affected. A parallel analysis performed in HepG2 revealed reduced MTTP, but not APOB, protein as a result of TRIB1 suppression. Global gene expression changes of human primary hepatocytes upon TRIB1 suppression were analyzed by clustering algorithms and found to be consistent with dysregulation of several pathways fundamental to liver function, including altered CEBPA and B transcript levels and impaired glucose handling. Indeed, TRIB1 expression in HepG2 cells was found to be inversely proportional to glucose concentration. Lastly TRIB1 downregulation in primary hepatocytes was associated with suppression of the HNF4A axis. In HepG2 cells, TRIB1 suppression resulted in reduced HNF4A protein levels while HNF4A suppression increased TRIB1 expression. Taken together these studies reveal an important role for TRIB1 in human hepatocyte biology. PMID:26657055

  11. Comparative Metabolism of Furan in Rodent and Human Cryopreserved Hepatocytes

    PubMed Central

    Gates, Leah A.; Phillips, Martin B.; Matter, Brock A.

    2014-01-01

    Furan is a liver toxicant and carcinogen in rodents. Although humans are most likely exposed to furan through a variety of sources, the effect of furan exposure on human health is still unknown. In rodents, furan requires metabolism to exert its toxic effects. The initial product of the cytochrome P450 2E1-catalyzed oxidation is a reactive α,β-unsaturated dialdehyde, cis-2-butene-1,4-dial (BDA). BDA is toxic and mutagenic and consequently is considered responsible for the toxic effects of furan. The urinary metabolites of furan in rats are derived from the reaction of BDA with cellular nucleophiles, and precursors to these metabolites are detected in furan-exposed hepatocytes. Many of these precursors are 2-(S-glutathionyl)butanedial-amine cross-links in which the amines are amino acids and polyamines. Because these metabolites are derived from the reaction of BDA with cellular nucleophiles, their levels are a measure of the internal dose of this reactive metabolite. To compare the ability of human hepatocytes to convert furan to the same metabolites as rodent hepatocytes, furan was incubated with cryopreserved human and rodent hepatocytes. A semiquantitative liquid chromatography with tandem mass spectrometry assay was developed for a number of the previously characterized furan metabolites. Qualitative and semiquantitative analysis of the metabolites demonstrated that furan is metabolized in a similar manner in all three species. These results indicate that humans may be susceptible to the toxic effects of furan. PMID:24751574

  12. Evaluating the uptake and intracellular fate of polystyrene nanoparticles by primary and hepatocyte cell lines in vitro

    SciTech Connect

    Johnston, Helinor J.; Semmler-Behnke, Manuela; Kreyling, Wolfgang; Stone, Vicki

    2010-01-01

    Nanoparticles (NPs) are being used within diverse applications such as medicines, clothing, cosmetics and food. In order to promote the safe development of such nanotechnologies it is essential to assess the potential adverse health consequences associated with human exposure. The liver is recognised as a target site for NP toxicity, due to NP accumulation within this organ subsequent to injection, inhalation or instillation. The uptake of fluorescent polystyrene carboxylated particles (20 nm or 200 nm diameter) by hepatocytes was determined using confocal microscopy; with cells imaged 'live' during particle exposure or after exposure within fixed cells. Comparisons between the uptake of polystyrene particles by primary rat hepatocytes, and human hepatocyte cell lines (C3A and HepG2) were made. Uptake of particles by hepatocytes was size, time, and serum dependent. Specifically, the uptake of 200 nm particles was limited, but 20 nm NPs were internalised by all cell types from 10 min onwards. At 10 min, 20 nm NP fluorescence co-localised with the tubulin cytoskeleton staining; after 30 min NP fluorescence compartmentalised into structures located within and/or between cells. The fate of internalised NPs was considered and they were not contained within early endosomes or lysosomes, but within mitochondria of cell lines. NPs accumulated within bile canaliculi to a limited extent, which suggests that NPs can be eliminated within bile. This is in keeping with the finding that gold NPs were eliminated in bile following intravenous injection into rats. The findings were, in the main, comparable between primary rat hepatocytes and the different human hepatocyte cell lines.

  13. Effects on 2,2’,4,4’-Tetrabromodiphenyl ether (BDE 47) on Thyroxine Metabolism and Transport in Primary Rat and Human Hepatocytes

    EPA Science Inventory

    Polybrominated diphenyl ethers (PBDEs), a major class of brominated flame retardants, are used in consumer products including furniture, electronics, textiles, and plastics. PBDEs bioaccumulate in wildlife and humans; BDE 47 is the predominant PBDE congener detected and typicall...

  14. RNAi Screening in Primary Human Hepatocytes of Genes Implicated in Genome-Wide Association Studies for Roles in Type 2 Diabetes Identifies Roles for CAMK1D and CDKAL1, among Others, in Hepatic Glucose Regulation

    PubMed Central

    Haney, Steven; Zhao, Juan; Tiwari, Shiwani; Eng, Kurt; Guey, Lin T.; Tien, Eric

    2013-01-01

    Genome-wide association (GWA) studies have described a large number of new candidate genes that contribute to of Type 2 Diabetes (T2D). In some cases, small clusters of genes are implicated, rather than a single gene, and in all cases, the genetic contribution is not defined through the effects on a specific organ, such as the pancreas or liver. There is a significant need to develop and use human cell-based models to examine the effects these genes may have on glucose regulation. We describe the development of a primary human hepatocyte model that adjusts glucose disposition according to hormonal signals. This model was used to determine whether candidate genes identified in GWA studies regulate hepatic glucose disposition through siRNAs corresponding to the list of identified genes. We find that several genes affect the storage of glucose as glycogen (glycolytic response) and/or affect the utilization of pyruvate, the critical step in gluconeogenesis. Of the genes that affect both of these processes, CAMK1D, TSPAN8 and KIF11 affect the localization of a mediator of both gluconeogenesis and glycolysis regulation, CRTC2, to the nucleus in response to glucagon. In addition, the gene CDKAL1 was observed to affect glycogen storage, and molecular experiments using mutant forms of CDK5, a putative target of CDKAL1, in HepG2 cells show that this is mediated by coordinate regulation of CDK5 and PKA on MEK, which ultimately regulates the phosphorylation of ribosomal protein S6, a critical step in the insulin signaling pathway. PMID:23840313

  15. Sex and strain differences in the hepatocyte primary culture/DNA repair test

    SciTech Connect

    McQueen, C.A.; Way, B.M. )

    1991-01-01

    The hepatocyte primary culture (HPC)/DNA repair test was developed using hepatocytes isolated from male F-344 rats. A number of genetic polymorphisms have been shown to occur in inbred strains of rats, which may lead to variation in biotransformation of xenobiotics resulting in differences in susceptibility to genotoxins. The effect of the strain utilized as a source of hepatocytes was investigated with female Lewis, F-344, and DA rats. Variation was observed when hepatocytes from the three strains were exposed to aflatoxin B{sub 1} (AFB{sub 1}). No clearcut strain differences were seen when cells were exposed to diethylnitrosamine (DEN) or 2-acetylaminofluorene. These results demonstrate that both the strain and the sex of the animal used as a source of hepatocytes can affect the HPC/DNA repair test.

  16. Transfection of Primary Hepatocytes with Liver-Enriched Transcription Factors Using Adenoviral Vectors.

    PubMed

    Benet, Marta; Jover, Ramiro; Bort, Roque

    2015-01-01

    Primary cultured hepatocytes are probably the best model to study endogenous metabolic pathways, toxicity, or drug metabolism. Many of these studies require expression of ectopic genes. It would be desirable to use a method of transfection that allows dose-response studies, high efficiency of transfection, and the possibility to express several genes at the same time. Adenoviral vectors fulfill these requirements, becoming a valuable tool for primary hepatocyte transfection. Moreover, they are easy to generate and do not require a high level of biocontainment. In the present chapter, we describe the generation, cloning, amplification, and purification of an adenoviral vector capable of infecting primary cultured hepatocytes. This recombinant adenovirus induces robust expression of the protein of interest in hepatocytes within a wide range of doses. PMID:26272145

  17. MicroRNA-561 promotes acetaminophen-induced hepatotoxicity in HepG2 cells and primary human hepatocytes through downregulation of the nuclear receptor corepressor dosage-sensitive sex-reversal adrenal hypoplasia congenital critical region on the X chromosome, gene 1 (DAX-1).

    PubMed

    Li, Minghua; Yang, Yinxue; He, Zhi-Xu; Zhou, Zhi-Wei; Yang, Tianxin; Guo, Peixuan; Zhang, Xueji; Zhou, Shu-Feng

    2014-01-01

    One of the major mechanisms involved in acetaminophen (APAP)-induced hepatotoxicity is hepatocyte nuclear factor 4α (HNF4α)-mediated activation of pregnane X receptor (PXR) and constitutive androstane receptor (CAR). In the present study, we investigated the role of miR-561 and its target gene DAX-1 encoding a corepressor of HNF4α in the process of APAP-induced hepatotoxicity. We used both human hepatocellular liver carcinoma cell line (HepG2) cells and primary human hepatocytes in this study and monitored the levels of reactive oxygen species, lactate dehydrogenase, and glutathione. Our bioinformatics study suggests an association between miR-561 and DAX-1, but not HNF4α. Treatment of HepG2 cells with APAP significantly reduced the expression of DAX-1 in a concentration-dependent manner. miR-561 was induced by APAP treatment in HepG2 cells. Transfection of HepG2 cells with an miR-561 mimic exacerbated APAP-induced hepatotoxicity. HNF4α is physically associated with DAX-1 in HepG2 cells. A decreased protein level of DAX-1 by APAP treatment was also enhanced by miR-561 mimic transfection in HepG2 cells and primary human hepatocytes. The basal and APAP-induced expression of PXR and CAR was enhanced by miR-561 mimic transfection; however, transfection of HepG2 cells or primary human hepatocytes with a miR-561 inhibitor or DAX-1 small interfering RNA reversed these effects. Additionally, the chromatin immunoprecipitation assay revealed that recruitment of DAX-1 onto the PXR promoter was inversely correlated with the recruitment of peroxisome proliferator-activated receptor-α coactivator-1α and HNF4α on APAP treatment. These results indicate that miR-561 worsens APAP-induced hepatotoxicity via inhibition of DAX-1 and consequent transactivation of nuclear receptors. PMID:24104199

  18. Comparison of cryopreserved HepaRG cells with cryopreserved human hepatocytes for prediction of clearance for 26 drugs.

    PubMed

    Zanelli, Ugo; Caradonna, Nicola Pasquale; Hallifax, David; Turlizzi, Elisa; Houston, J Brian

    2012-01-01

    Prediction of clearance in drug discovery currently relies on human primary hepatocytes, which can vary widely in drug-metabolizing enzyme activity. Potential alternative in vitro models include the HepaRG cell (from immortalized hepatoma cells), which in culture can express drug-metabolizing enzymes to an extent comparable to that of primary hepatocytes. Utility of the HepaRG cell will depend on robust performance, relative to that of primary hepatocytes, in routine high-throughput analysis. In this study, we compared intrinsic clearance (CL(int)) in the recently developed cryopreserved HepaRG cell system with CL(int) in human cryopreserved pooled hepatocytes and with CL(int) in vivo for 26 cytochrome P450 substrate drugs. There was quantitative agreement between CL(int) in HepaRG cells and human hepatocytes, which was linear throughout the range of CL(int) (1-2000 ml · min(-1) · kg(-1)) and not dependent on particular cytochrome P450 involvement. Prediction of CL(int) in HepaRG cells was on average within 2-fold of in vivo CL(int) (using the well stirred liver model), but average fold error was clearance-dependent with greater underprediction (up to at least 5-fold) for the more highly cleared drugs. Recent reporting of this phenomenon in human hepatocytes was therefore confirmed with the hepatocytes used in this study, and hence the HepaRG cell system appears to share an apparently general tendency of clearance-limited CL(int) in cell models. This study shows the cryopreserved HepaRG cell system to be quantitatively comparable to human hepatocytes for prediction of clearance of drug cytochrome P450 substrates and to represent a promising alternative in vitro tool. PMID:21998403

  19. Applicability of second-generation upcyte® human hepatocytes for use in CYP inhibition and induction studies

    PubMed Central

    Ramachandran, Sarada D; Vivarès, Aurélie; Klieber, Sylvie; Hewitt, Nicola J; Muenst, Bernhard; Heinz, Stefan; Walles, Heike; Braspenning, Joris

    2015-01-01

    Human upcyte® hepatocytes are proliferating hepatocytes that retain many characteristics of primary human hepatocytes. We conducted a comprehensive evaluation of the application of second-generation upcyte® hepatocytes from four donors for inhibition and induction assays using a selection of reference inhibitors and inducers. CYP1A2, CYP2B6, CYP2C9, and CYP3A4 were reproducibly inhibited in a concentration-dependent manner and the calculated IC50 values for each compound correctly classified them as potent inhibitors. Upcyte® hepatocytes were responsive to prototypical CYP1A2, CYP2B6, CYP2C9, and CYP3A4 inducers, confirming that they have functional AhR-, CAR-, and PXR-mediated CYP regulation. A panel of 11 inducers classified as potent, moderate or noninducers of CYP3A4 and CYP2B6 were tested. There was a good fit of data from upcyte® hepatocytes to three different predictive models for CYP3A4 induction, namely the Relative Induction Score (RIS), AUCu/F2, and Cmax,u/Ind50. In addition, PXR (rifampicin) and CAR-selective (carbamazepine and phenytoin) inducers of CYP3A4 and CYP2B6 induction, respectively, were demonstrated. In conclusion, these data support the use of second-generation upcyte® hepatocytes for CYP inhibition and induction assays. Under the culture conditions used, these cells expressed CYP activities that were equivalent to or higher than those measured in primary human hepatocyte cultures, which could be inhibited or induced by prototypical CYP inhibitors and inducers, respectively. Moreover, they can be used to predict in vivo CYP3A4 induction potential using three prediction models. Bulk availability of cells from multiple donors makes upcyte® hepatocytes suitable for DDI screening, as well as more in-depth mechanistic investigations. PMID:26516577

  20. Differential Impacts of Soybean and Fish Oils on Hepatocyte Lipid Droplet Accumulation and Endoplasmic Reticulum Stress in Primary Rabbit Hepatocytes

    PubMed Central

    Zhu, Xueping; Xiao, Zhihui; Xu, Yumin; Zhao, Xingli; Cheng, Ping; Cui, Ningxun; Cui, Mingling; Li, Jie; Zhu, Xiaoli

    2016-01-01

    Parenteral nutrition-associated liver disease (PNALD) is a severe ailment associated with long-term parenteral nutrition. Soybean oil-based lipid emulsions (SOLE) are thought to promote PNALD development, whereas fish oil-based lipid emulsions (FOLE) are thought to protect against PNALD. This study aimed to investigate the effects of SOLE and FOLE on primary rabbit hepatocytes. The results reveal that SOLE caused significant endoplasmic reticulum (ER) and mitochondrial damage, ultimately resulting in lipid droplets accumulation and ER stress. While these deleterious events induce hepatocyte injury, FOLE at high doses cause only minor ER and mitochondrial damage, which has no effect on hepatic function. SOLE also significantly upregulated glucose-regulated protein 94 mRNA and protein expression. These data indicate that SOLE, but not FOLE, damage the ER and mitochondria, resulting in lipid droplets accumulation and ER stress and, finally, hepatocyte injury. This likely contributes to the differential impacts of SOLE and FOLE on PNALD development and progression. PMID:27057162

  1. Proteomic analysis of primary duck hepatocytes infected with duck hepatitis B virus

    PubMed Central

    2010-01-01

    Background Hepatitis B virus (HBV) is a major cause of liver infection in human. Because of the lack of an appropriate cell culture system for supporting HBV infection efficiently, the cellular and molecular mechanisms of hepadnavirus infection remain incompletely understood. Duck heptatitis B virus (DHBV) can naturally infect primary duck hepatocytes (PDHs) that provide valuable model systems for studying hepadnavirus infection in vitro. In this report, we explored global changes in cellular protein expression in DHBV infected PDHs by two-dimension gel electrophoresis (2-DE) combined with MALDI-TOF/TOF tandem mass spectrometry (MS/MS). Results The effects of hepadnavirus infection on hepatocytes were investigated in DHBV infected PDHs by the 2-DE analysis. Proteomic profile of PDHs infected with DHBV were analyzed at 24, 72 and 120 h post-infection by comparing with uninfected PDHs, and 75 differentially expressed protein spots were revealed by 2-DE analysis. Among the selected protein spots, 51 spots were identified corresponding to 42 proteins by MS/MS analysis; most of them were matched to orthologous proteins of Gallus gallus, Anas platyrhynchos or other avian species, including alpha-enolase, lamin A, aconitase 2, cofilin-2 and annexin A2, etc. The down-regulated expression of beta-actin and annexin A2 was confirmed by Western blot analysis, and potential roles of some differentially expressed proteins in the virus-infected cells have been discussed. Conclusions Differentially expressed proteins of DHBV infected PDHs revealed by 2-DE, are involved in carbohydrate metabolism, amino acid metabolism, stress responses and cytoskeleton processes etc, providing the insight to understanding of interactions between hepadnavirus and hepatocytes and molecular mechanisms of hepadnavirus pathogenesis. PMID:20529248

  2. U. v. -enhanced reactivation of u. v. -irradiated herpes virus by primary cultures of rat hepatocytes

    SciTech Connect

    Zurlo, J.; Yager, J.D. )

    1984-04-01

    Carcinogen treatment of cultured mammalian cells prior to infection with u.v.-irradiated virus results in enhanced virus survival and mutagenesis suggesting the induction of SOS-type processes. The development of a primary rat hepatocyte culture system is reported to investigate cellular responses to DNA damage which may be relevant to hepatocarcinogenesis in vivo. Enhanced reactivation of u.v.-irradiated Herpes simplex virus type 1 (HSV-1) occurred in hepatocytes irradiated with u.v. Cultured hepatocytes were pretreated with u.v. at the time of enhanced DNA synthesis. These treatments caused an inhibition followed by a recovery of DNA synthesis. At various times after pretreatment, the hepatocytes were infected with control or u.v.-irradiated HSV-1 at low multiplicity, and virus survival was measured. U.v.-irradiated HSV-1 exhibited the expected two-component survival curve in control or u.v. pretreated hepatocytes. The magnitude of enhanced reactivation of HSV-1 was dependent on the u.v. dose to the hepatocytes, the time of infection following u.v. pretreatment, and the level of DNA synthesis at the time of pretreatment. These results suggest that u.v. treatment of rat hepatocytes causes the induction of SOS-type functions tht may have a role in the initiation of hepatocarcinogenesis.

  3. Impact of Nanotopography, Heparin Hydrogel Microstructures, and Encapsulated Fibroblasts on Phenotype of Primary Hepatocytes

    PubMed Central

    2015-01-01

    Hepatocytes, the main epithelial cell type in the liver, perform most of the biochemical functions of the liver. Thus, maintenance of a primary hepatocyte phenotype is crucial for investigations of in vitro drug metabolism, toxicity, and development of bioartificial liver constructs. Here, we report the impact of topographic cues alone and in combination with soluble signals provided by encapsulated feeder cells on maintenance of the primary hepatocyte phenotype. Topographic features were 300 nm deep with pitches of either 400, 1400, or 4000 nm. Hepatocyte cell attachment, morphology and function were markedly better on 400 nm pitch patterns compared with larger scale topographies or planar substrates. Interestingly, topographic features having biomimetic size scale dramatically increased cell adhesion whether or not substrates had been precoated with collagen I. Albumin production in primary hepatocytes cultured on 400 nm pitch substrates without collagen I was maintained over 10 days and was considerably higher compared to albumin synthesis on collagen-coated flat substrates. In order to investigate the potential interaction of soluble cytoactive factors supplied by feeder cells with topographic cues in determining cell phenotype, bioactive heparin-containing hydrogel microstructures were molded (100 μm spacing, 100 μm width) over the surface of the topographically patterned substrates. These hydrogel microstructures either carried encapsulated fibroblasts or were free of cells. Hepatocytes cultured on nanopatterned substrates next to fibroblast carrying hydrogel microstructures were significantly more functional than hepatocytes cultured on nanopatterned surfaces without hydrogels or stromal cells significantly elevated albumin expression and cell junction formation compared to cells provided with topographic cues only. The simultaneous presentation of topographic biomechanical cues along with soluble signaling molecules provided by encapsulated fibroblasts

  4. Metabolism of ochratoxin A by primary cultures of rat hepatocytes.

    PubMed Central

    Hansen, C E; Dueland, S; Drevon, C A; Størmer, F C

    1982-01-01

    Association of ochratoxin A with cultured rat hepatocytes occurs at 4 degrees C, and the saturation level in the medium is 0.3 mM ochratoxin A, with maximal binding after 60 min. At 37 degrees C the level of cell-associated ochratoxin A increased up to 6 h and remained at 2 nmol of toxin per mg of cell protein for 30 h. With increasing concentrations of ochratoxin A, increasing amounts of the toxin accumulated in the cells; saturation occurred at a concentration of 0.3 mM. Ochratoxin A was metabolized by hepatocytes at 37 degrees. (4R)-4-Hydroxyochratoxin A appeared in the medium at a maximal level (about 30 nmol/mg of cell protein) at an ochratoxin A concentration of 0.25 mM after 48 h of incubation. Small amounts of (4S)-4-hydroxyochratoxin A were detected only after incubation for 22 h or longer. PMID:7103484

  5. A novel bile acid-activated vitamin D receptor signaling in human hepatocytes.

    PubMed

    Han, Shuxin; Li, Tiangang; Ellis, Ewa; Strom, Stephen; Chiang, John Y L

    2010-06-01

    Vitamin D receptor (VDR) is activated by natural ligands, 1alpha, 25-dihydroxy-vitamin D(3) [1alpha,25(OH)(2)-D(3)] and lithocholic acid (LCA). Our previous study shows that VDR is expressed in human hepatocytes, and VDR ligands inhibit bile acid synthesis and transcription of the gene encoding cholesterol 7alpha-hydroxylase (CYP7A1). Primary human hepatocytes were used to study LCA and 1alpha,25(OH)(2)-D(3) activation of VDR signaling. Confocal immunofluorescent microscopy imaging and immunoblot analysis showed that LCA and 1alpha, 25(OH)(2)-D(3) induced intracellular translocation of VDR from the cytosol to the nucleus and also plasma membrane where VDR colocalized with caveolin-1. VDR ligands induced tyrosine phosphorylation of c-Src and VDR and their interaction. Inhibition of c-Src abrogated VDR ligand-dependent inhibition of CYP7A1 mRNA expression. Kinase assays showed that VDR ligands specifically activated the c-Raf/MEK1/2/extracellular signal-regulated kinase (ERK) 1/2 pathway, which stimulates serine phosphorylation of VDR and hepatocyte nuclear factor-4alpha, and their interaction. Mammalian two-hybrid assays showed a VDR ligand-dependent interaction of nuclear receptor corepressor-1 and silencing mediator of retinoid and thyroid with VDR/retinoid X receptor-alpha (RXRalpha). Chromatin immunoprecipitation assays revealed that an ERK1/2 inhibitor reversed VDR ligand-induced recruitment of VDR, RXRalpha, and corepressors to human CYP7A1 promoter. In conclusion, VDR ligands activate membrane VDR signaling to activate the MEK1/2/ERK1/2 pathway, which stimulates nuclear VDR/RXRalpha recruitment of corepressors to inhibit CYP7A1 gene transcription in human hepatocytes. This membrane VDR-signaling pathway may be activated by bile acids to inhibit bile acid synthesis as a rapid response to protect hepatocytes from cholestatic liver injury. PMID:20371703

  6. Cryopreservation of isolated human hepatocytes for transplantation: State of the art.

    PubMed

    Terry, Claire; Dhawan, Anil; Mitry, Ragai R; Hughes, Robin D

    2006-10-01

    Hepatocytes isolated from unused donor livers are being used for transplantation in patients with acute liver failure and liver-based metabolic defects. As large numbers of hepatocytes can be prepared from a single liver and hepatocytes need to be available for emergency and repeated treatment of patients it is essential to be able to cryopreserve and store cells with good thawed cell function. This review considers the current status of cryopreservation of human hepatocytes discussing the different stages involved in the process. These include pre-treatment of cells, freezing solution, cryoprotectants and freezing and thawing protocols. There are detrimental effects of cryopreservation on hepatocyte structure and metabolic function, including cell attachment, which is important to the engraftment of transplanted cells in the liver. Cryopreserved human hepatocytes have been successfully used in clinical transplantation, with evidence of replacement of missing function. Further optimisation of hepatocyte cryopreservation protocols is important for their use in hepatocyte transplantation. PMID:16793034

  7. New physiologically-relevant liver tissue model based on hierarchically cocultured primary rat hepatocytes with liver endothelial cells.

    PubMed

    Xiao, Wenjin; Perry, Guillaume; Komori, Kikuo; Sakai, Yasuyuki

    2015-11-01

    To develop an in vitro liver tissue equivalent, hepatocytes should be cocultured with liver non-parenchymal cells to mimic the in vivo physiological microenvironments. In this work, we describe a physiologically-relevant liver tissue model by hierarchically organizing layers of primary rat hepatocytes and human liver sinusoidal endothelial cells (TMNK-1) on an oxygen-permeable polydimethylsiloxane (PDMS) membrane, which facilitates direct oxygenation by diffusion through the membrane. This in vivo-mimicking hierarchical coculture was obtained by simply proceeding the overlay of TMNK-1 cells on the hepatocyte layer re-formed on the collagen immobilized PDMS membranes. The comparison of hepatic functionalities was achieved between coculture and sandwich culture with Matrigel, in the presence and absence of direct oxygenation. A complete double-layered structure of functional liver cells with vertical contact between hepatocytes and TMNK-1 was successfully constructed in the coculture with direct oxygen supply and was well-maintained for 14 days. The hepatocytes in this hierarchical culture exhibited improved survival, functional bile canaliculi formation, cellular level polarization and maintenance of metabolic activities including Cyp1A1/2 activity and albumin production. By contrast, the two cell populations formed discontinuous monolayers on the same surfaces in the non-oxygen-permeable cultures. These results demonstrate that (i) the direct oxygenation through the PDMS membranes enables very simple formation of a hierarchical structure consisting of a hepatocyte layer and a layer of TMNK-1 and (ii) we may include other non-parenchymal cells in this format easily, which can be widely applicable to other epithelial organs. PMID:26304784

  8. Characterization of lipid metabolism in a novel immortalized human hepatocyte cell line

    PubMed Central

    Green, Charlotte J.; Johnson, Deborah; Amin, Harsh D.; Sivathondan, Pamela; Silva, Michael A.; Wang, Lai Mun; Stevanato, Lara; McNeil, Catriona A.; Miljan, Erik A.; Sinden, John D.; Morten, Karl J.

    2015-01-01

    The development of hepatocyte cell models that represent fatty acid partitioning within the human liver would be beneficial for the study of the development and progression of nonalcoholic fatty liver disease (NAFLD). We sought to develop and characterize a novel human liver cell line (LIV0APOLY) to establish a model of lipid accumulation using a physiological mixture of fatty acids under low- and high-glucose conditions. LIV0APOLY cells were compared with a well-established cell line (HepG2) and, where possible, primary human hepatocytes. LIV0APOLY cells were found to proliferate and express some mature liver markers and were wild type for the PNPLA3 (rs738409) gene, whereas HepG2 cells carried the Ile148Met variant that is positively associated with liver fat content. Intracellular triglyceride content was higher in HepG2 than in LIV0APOLY cells; exposure to high glucose and/or exogenous fatty acids increased intracellular triglyceride in both cell lines. Triglyceride concentrations in media were higher from LIV0APOLY compared with HepG2 cells. Culturing LIV0APOLY cells in high glucose increased a marker of endoplasmic reticulum stress and attenuated insulin-stimulated Akt phosphorylation whereas low glucose and exogenous fatty acids increased AMPK phosphorylation. Although LIV0APOLY cells and primary hepatocytes stored similar amounts of exogenous fatty acids as triglyceride, more exogenous fatty acids were partitioned toward oxidation in the LIV0APOLY cells than in primary hepatocytes. LIV0APOLY cells offer the potential to be a renewable cellular model for studying the effects of exogenous metabolic substrates on fatty acid partitioning; however, their usefulness as a model of lipoprotein metabolism needs to be further explored. PMID:26126685

  9. Sulfated Oxysterol, 25HC3S, is a Potent Regulator of Lipid Metabolism in Human Hepatocytes

    PubMed Central

    Ren, Shunlin; Li, Xiaobo; Rodriguez-Agudo, Daniel; Gil, Gregorio; Hylemon, Phillip; Pandak, William M.

    2009-01-01

    Recently, a novel oxysterol, 5-cholesten-3β, 25-diol 3-sulfate (25HC3S) was identified in primary rat hepatocytes following overexpression of the cholesterol transport protein, StarD1. This oxysterol was also detected in human liver nuclei. In the present study, 25HC3S was chemically synthesized. Addition of 25HC3S (6 μM) to human hepatocytes markedly inhibited cholesterol biosynthesis. Quantitative RT-PCR and Western blot analysis showed that 25HC3S strongly decreased HMG-CoA reductase mRNA and protein levels. Coincidently, 25HC3S inhibited the activation of sterol regulatory element binding proteins (SREBPs), suggesting that inhibition of cholesterol biosynthesis occurred via blocking SREBP-1 activation, and subsequently inhibiting the expression of HMG CoA reductase. 25HC3S decreased SREBP-1 mRNA levels and inhibited the expression of target genes encoding acetyl CoA carboxylase-1 (ACC-1) and fatty acid synthase (FAS). In contract, 25-hydroxycholesterol increased SREBP1 and FAS mRNA levels in primary human hepatocytes. The results imply that 25HC3S is a potent regulator of SREBPs mediated lipid metabolism. PMID:17624300

  10. Novel immortalized human fetal liver cell line, cBAL111, has the potential to differentiate into functional hepatocytes

    PubMed Central

    Deurholt, Tanja; van Til, Niek P; Chhatta, Aniska A; ten Bloemendaal, Lysbeth; Schwartlander, Ruth; Payne, Catherine; Plevris, John N; Sauer, Igor M; Chamuleau, Robert AFM; Elferink, Ronald PJ Oude; Seppen, Jurgen; Hoekstra, Ruurdtje

    2009-01-01

    Background A clonal cell line that combines both stable hepatic function and proliferation capacity is desirable for in vitro applications that depend on hepatic function, such as pharmacological or toxicological assays and bioartificial liver systems. Here we describe the generation and characterization of a clonal human cell line for in vitro hepatocyte applications. Results Cell clones derived from human fetal liver cells were immortalized by over-expression of telomerase reverse transcriptase. The resulting cell line, cBAL111, displayed hepatic functionality similar to the parental cells prior to immortalization, and did not grow in soft agar. Cell line cBAL111 expressed markers of immature hepatocytes, like glutathione S transferase and cytokeratin 19, as well as progenitor cell marker CD146 and was negative for lidocaine elimination. On the other hand, the cBAL111 cells produced urea, albumin and cytokeratin 18 and eliminated galactose. In contrast to hepatic cell lines NKNT-3 and HepG2, all hepatic functions were expressed in cBAL111, although there was considerable variation in their levels compared with primary mature hepatocytes. When transplanted in the spleen of immunodeficient mice, cBAL111 engrafted into the liver and partly differentiated into hepatocytes showing expression of human albumin and carbamoylphosphate synthetase without signs of cell fusion. Conclusion This novel liver cell line has the potential to differentiate into mature hepatocytes to be used for in vitro hepatocyte applications. PMID:19845959

  11. Changes in gluconeogenesis and intracellular lipid accumulation characterize uremic human hepatocytes ex vivo.

    PubMed

    Li, Meng; Ellis, Ewa; Johansson, Helene; Nowak, Greg; Isaksson, Bengt; Gnocchi, Davide; Parini, Paolo; Axelsson, Jonas

    2016-06-01

    It is well known that reduced glomerular filtration rate (GFR) leads to an increased risk of dyslipidemia, insulin resistance, and cardiovascular mortality. The liver is a central organ for metabolism, but its function in the uremic setting is still poorly characterized. We used human primary hepatocytes isolated from livers of nine donors with normal renal function to investigate perturbations in key metabolic pathways following exposure to uremic (n = 8) or healthy (n = 8) sera, and to serum-free control medium. Both uremic and healthy elicited consistent responses from hepatocytes from multiple donors and compared with serum-free control. However, at physiological insulin concentrations, uremic cells accumulated 56% more intracellular lipids. Also, when comparing uremic with healthy medium after culture, it contained more very-low-density lipoprotein-triglyceride and glucose. These changes were accompanied by decreased phosphorylation of AktS473 mRNA levels of key regulators of gluconeogenesis in uremic sera-treated hepatocytes such as phosphoenolpyruvate carboxykinase 1 and glucose 6-phosphate were elevated. We also found increased expression of 11β-hydroxysteroid dehydrogenase mRNA in uremic cells, along with high phosphorylation of downstream p53 and phospholipase C-γ1Y783 Thus our ex vivo data suggest that the uremic hepatocytes rapidly develop a glycogenic and lipogenic condition accompanied by perturbations in a large number of signaling networks. PMID:27056725

  12. Aging lowers steady-state antioxidant enzyme and stress protein expression in primary hepatocytes.

    PubMed

    Hall, D M; Sattler, G L; Sattler, C A; Zhang, H J; Oberley, L W; Pitot, H C; Kregel, K C

    2001-06-01

    It has been reported that the isolation and culture of primary hepatocytes can compromise cellular ability to constituitively express antioxidant enzyme (AE) genes, making it difficult to study their regulation ex vivo. In the present study, the steady-state expression of manganese-containing superoxide dismutase, copper- and zinc-containing superoxide dismutase, catalase, and glutathione peroxidase was assessed in primary hepatocytes isolated from young and senescent rats and cultured in MATRIGEL: There was no change in steady-state superoxide dismutase protein or activity levels in cells collected from young animals and cultured for 7 days. Catalase expression was initially increased, and then it declined 30%. In contrast, superoxide dismutase expression declined 60% and catalase expression declined 50% in cells from senescent animals. Constitutive and inducible 70-kDa heat shock protein expression increased coincident with declining AE levels in the young cells but not senescent cells. For both age groups, electron micrographs showed rounded hepatocytes with abundant rough endoplasmic reticulum, mitochondria, and peroxisomes. Hepatocytes were organized into clusters of 6-12 cells surrounding a large central lumen devoid of microvilli. Each cluster also contained smaller microvilli-lined lumens between adjacent hepatocytes that resembled canniculi. The plasma membranes of these lumens were sealed from the extracellular space by junctional complexes. Gap junctions in the plasma membrane suggest that hepatocytes were capable of intercellular communication. We conclude that the Matrigel system can be used to study AE regulation in primary hepatocytes from young and senescent animals, provided that experiments can be conducted within a time frame of 5-7 days in culture. These data also support the hypothesis that aging compromises hepatocellular ability to maintain AE status and upregulate stress protein expression. PMID:11382788

  13. Vasopressin inhibits type-I collagen and albumin gene expression in primary cultures of adult rat hepatocytes

    SciTech Connect

    Chojkier, M.; Brenner, D.A.; Leffert, H.L.

    1989-06-05

    The mechanisms that regulate collagen gene expression in hepatic cells are poorly understood. Accelerated Ca2+ fluxes are associated with inhibiting collagen synthesis selectively in human fibroblasts. In suspension cultures of isolated hepatocytes, the Ca2+ agonist vasopressin increases cytosolic levels of free Ca2+. However, whether vasopressin's interactions with plasma membrane V1 receptors attenuate hepatic collagen production is unknown. We investigated this problem by studying vasopressin's effects on collagen synthesis and Ca2+ efflux in long-term primary cultures of differentiated and proliferation-competent adult rat hepatocytes. Twelve-day-old quiescent cultures were exposed to test substances and labeled with (5-3H)proline. Determinations of radioactivity in collagenase-sensitive and collagenase-resistant proteins were used to calculate the relative levels of collagen production. Synthetic (8-arg)vasopressin stimulated 45Ca2+ efflux within 1 min and inhibited hepatocyte collagen production within 3 h by 50%; overall rates of protein synthesis were not affected significantly. In cultures labeled with (35S)methionine, vasopressin also decreased the levels of newly synthesized and secreted albumin, but not fibrinogen, detected in specific immunoprecipitates analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Northern blot analyses using specific (32P)cDNA probes revealed 70% decreases in hybridizable levels of collagen alpha 1(I) mRNA in hepatocyte cultures treated with either vasopressin or Ca2+ ionophore A23187; hybridizable levels of albumin mRNA also fell approximately 50% following vasopressin treatment.

  14. Potential interactions between HIV drugs, ritonavir and efavirenz and anticancer drug, nilotinib--a study in primary cultures of human hepatocytes that is applicable to HIV patients with cancer.

    PubMed

    Pillai, Venkateswaran C; Parise, Robert A; Christner, Susan M; Rudek, Michelle A; Beumer, Jan H; Venkataramanan, Raman

    2014-11-01

    Nilotinib is used to treat chronic myeloid leukemia (CML), and is metabolized by CYP3A. With a black-box warning for QT prolongation, which is exposure dependent, controlling for drug interactions is clinically relevant. Treatments of HIV patients with CML are with HAART drugs, ritonavir and efavirenz, may cause complex drug interactions through CYP3A inhibition or induction. We evaluated the interactions of ritonavir or efavirenz on nilotinib using human hepatocytes and compared these interactions with those of ketoconazole or rifampin, classical CYP3A inhibitor and inducer, respectively. Hepatocytes were treated with vehicle, ritonavir (10 μM), ketoconazole (10 μM), efavirenz (10 μM), or rifampin (10 μM) for 5 days. On day 5, nilotinib (3 μM) was coincubated for an additional 24-48 hours. The concentrations of nilotinib were quantitated in collected samples (combined lysate and medium) by LC-MS. Apparent intrinsic clearance (CL(int,app)) of nilotinib was lowered 5.8- and 3.1-fold, respectively, by ritonavir and ketoconazole. Efavirenz and rifampin increased the CL(int,app) of nilotinib by 2.1- and 4.1-fold, respectively. The clinically recommended dose (300 mg twice daily) of nilotinib may have to be reduced substantially (150 mg once daily) or increased (400 mg thrice daily), respectively, to achieve desired drug exposure, when ritonavir or efavirenz is co-administered. PMID:24846165

  15. Antiviral activity and host gene induction by tamarin and marmoset interferon-α and interferon-γ in the GBV-B primary hepatocyte culture model

    PubMed Central

    Chavez, Deborah; Guerra, Bernadette; Lanford, Robert E.

    2009-01-01

    GBV-B induces hepatitis in tamarins and marmosets and is a surrogate model for HCV infections. Here, we cloned and characterized the antiviral activity of tamarin and marmoset interferon (IFN)α and IFNγ. Potent antiviral activity was observed for tamarin and marmoset IFNα in primary hepatocyte cultures infected with GBV-B. The antiviral activity was greater in cultures exposed to IFNα prior to GBV-B infection, suggesting that either GBV-B was capable of inhibition of the antiviral activity of exogenous IFNα or that the preexisting endogenous IFN response to the virus reduced efficacy to exogenous IFNα. IFNγ also exhibited antiviral activity in GBV-B infected hepatocytes. The transcriptional response to IFNα in marmoset hepatocytes was characterized using human genome microarrays. Since the GBV-B hepatocyte culture model possesses a functional innate immune response, it will provide opportunities to explore the nature of the antiviral response to a virus closely related to HCV. PMID:19501869

  16. Titanium Dioxide Nanoparticles Trigger Loss of Function and Perturbation of Mitochondrial Dynamics in Primary Hepatocytes

    PubMed Central

    Natarajan, Vaishaali; Wilson, Christina L.; Hayward, Stephen L.; Kidambi, Srivatsan

    2015-01-01

    Titanium dioxide (TiO2) nanoparticles are one of the most highly manufactured and employed nanomaterials in the world with applications in copious industrial and consumer products. The liver is a major accumulation site for many nanoparticles, including TiO2, directly through intentional exposure or indirectly through unintentional ingestion via water, food or animals and increased environmental contamination. Growing concerns over the current usage of TiO2 coupled with the lack of mechanistic understanding of its potential health risk is the motivation for this study. Here we determined the toxic effect of three different TiO2 nanoparticles (commercially available rutile, anatase and P25) on primary rat hepatocytes. Specifically, we evaluated events related to hepatocyte functions and mitochondrial dynamics: (1) urea and albumin synthesis using colorimetric and ELISA assays, respectively; (2) redox signaling mechanisms by measuring reactive oxygen species (ROS) production, manganese superoxide dismutase (MnSOD) activity and mitochondrial membrane potential (MMP); (3) OPA1 and Mfn-1 expression that mediates the mitochondrial dynamics by PCR; and (4) mitochondrial morphology by MitoTracker Green FM staining. All three TiO2 nanoparticles induced a significant loss (p < 0.05) in hepatocyte functions even at concentrations as low as 50 ppm with commercially used P25 causing maximum damage. TiO2 nanoparticles induced a strong oxidative stress in primary hepatocytes. TiO2 nanoparticles exposure also resulted in morphological changes in mitochondria and substantial loss in the fusion process, thus impairing the mitochondrial dynamics. Although this study demonstrated that TiO2 nanoparticles exposure resulted in substantial damage to primary hepatocytes, more in vitro and in vivo studies are required to determine the complete toxicological mechanism in primary hepatocytes and subsequently liver function. PMID:26247363

  17. Polygonal networks, "geodomes", of adult rat hepatocytes in primary culture.

    PubMed

    Mochizuki, Y; Furukawa, K; Mitaka, T; Yokoi, T; Kodama, T

    1988-01-01

    Polygonal networks, "geodomes", in cultured hepatocytes of adult rats were examined by both light and electron microscopy. On light microscopical examinations of specimens stained with Coomassie blue after the treatment with Triton X-100, the networks were detected 5 days after culture, which consisted of triangles arranged mainly in hexagonal patterns. They surrounded main cell body, looking like a headband, or were occasionally situated over nuclei, looking like a geodesic dome. Scanning electron microscopical observations after Triton treatment revealed that these structures were located underneath surface membrane. Transmission electron microscopical investigations revealed that the connecting fibers of networks consisted of microfilaments which radiated in a compact bundle from electron-dense vertices. PMID:3396075

  18. Novel Recombinant Hepatitis B Virus Vectors Efficiently Deliver Protein and RNA Encoding Genes into Primary Hepatocytes

    PubMed Central

    Hong, Ran; Bai, Weiya; Zhai, Jianwei; Liu, Wei; Li, Xinyan; Zhang, Jiming; Cui, Xiaoxian; Zhao, Xue; Ye, Xiaoli; Deng, Qiang; Tiollais, Pierre; Wen, Yumei

    2013-01-01

    Hepatitis B virus (HBV) has extremely restricted host and hepatocyte tropism. HBV-based vectors could form the basis of novel therapies for chronic hepatitis B and other liver diseases and would also be invaluable for the study of HBV infection. Previous attempts at developing HBV-based vectors encountered low yields of recombinant viruses and/or lack of sufficient infectivity/cargo gene expression in primary hepatocytes, which hampered follow-up applications. In this work, we constructed a novel vector based on a naturally occurring, highly replicative HBV mutant with a 207-bp deletion in the preS1/polymerase spacer region. By applying a novel insertion strategy that preserves the continuity of the polymerase open reading frame (ORF), recombinant HBV (rHBV) carrying protein or small interfering RNA (siRNA) genes were obtained that replicated and were packaged efficiently in cultured hepatocytes. We demonstrated that rHBV expressing a fluorescent reporter (DsRed) is highly infective in primary tree shrew hepatocytes, and rHBV expressing HBV-targeting siRNA successfully inhibited antigen expression from coinfected wild-type HBV. This novel HBV vector will be a powerful tool for hepatocyte-targeting gene delivery, as well as the study of HBV infection. PMID:23552416

  19. Toxicity and uptake mechanism of cylindrospermopsin and lophyrotomin in primary rat hepatocytes.

    PubMed

    Chong, M W K; Wong, B S F; Lam, P K S; Shaw, G R; Seawright, A A

    2002-02-01

    The toxicities and uptake mechanisms of two hepatotoxins, namely cylindrospermopsin and lophyrotomin, were investigated on primary rat hepatocytes by using microcystin-LR (a well-known hepatotoxin produced by cyanobacteria) as a comparison. Isolated rat hepatocytes were incubated with different concentrations of hepatotoxins for 0, 24, 48 and 72 h. The cell viability was assayed by the tetrazolium-based (MTT) assay. Microcystin-LR, cylindrospermopsin and lophyrotomin all exhibited toxic effects on the primary rat hepatocytes with 72-h LC(50) of 8, 40 and 560 ng/ml, respectively. The involvement of the bile acid transport system in the hepatotoxin-induced toxicities was tested in the presence of two bile acids, cholate and taurocholate. Results showed that the bile acid transport system was responsible for the uptake, and facilitated the subsequent toxicities of lophyrotomin on hepatocytes. This occurred to a much lesser extent with cylindrospermopsin. With its smaller molecular weight, passive diffusion might be one of the possible mechanisms for cylindrospermopsin uptake into hepatocytes. This was supported by incubating a permanent cell line, KB (devoid of bile acid transport system), with cylindrospermopsin which showed cytotoxic effects. No inhibition of protein phosphatase 2A by cylindrospermopsin or lophyrotomin was found. This indicated that other toxic mechanisms besides protein phosphatase inhibition were producing the toxicities of cylindrospermopsin and lophyrotomin, and that they were unlikely to be potential tumor promoters. PMID:11689242

  20. Induction of lacZ Mutations in Muta™Mouse Primary Hepatocytes

    PubMed Central

    Chen, Guosheng; Gingerich, John; Soper, Lynda; Douglas, George R; White, Paul A

    2010-01-01

    We have developed an in vitro mutation assay using primary hepatocytes from the transgenic Muta™Mouse. Primary hepatocytes were isolated using a two-step perfusion method with purification by Percoll, cultured, and treated with benzo[a]pyrene (BaP), 2-amino-1-methyl-6-phenyl- imidazo[4,5-b]pyridine (PhIP), 3-nitrobenzoanthrone (3-NBA), and cigarette smoke condensate (CSC). The mean lacZ mutant frequency (MF) for the solvent control was approximately twofold greater than the spontaneous MF observed in liver tissue. A concentration-dependent increase in MF (up to 3.7-fold above control) was observed following exposure to BaP. Fourfold and twofold increases in mutant frequency were observed for 3-NBA and PhIP exposures, respectively, without the addition of any exogenous metabolic activation. A slight but statistically significant increase in lacZ MF was observed for CSC, but only at the lowest concentration. This is the first report demonstrating that mutations can be detected in cultured primary hepatocytes from Muta™Mouse. The preliminary results presented suggest that the Muta™Mouse primary hepatocyte mutagenicity assay can be used as a cost-effective tool for screening of environmental mutagens and therapeutic products. Environ. Mol. Mutagen. 51:330–337, 2010. © 2009 Wiley-Liss, Inc. PMID:19953605

  1. SELENIUM MODIFIES THE METABOLISM AND TOXICITY OF ARSENIC IN PRIMARY RAT HEPATOCYTES

    EPA Science Inventory

    ABSTRACT
    Selenium Modifies the Metabolism and Toxicity of Arsenic in Primary Rat Hepatocytes. Miroslav Styblo, David J. Thomas (2000) Toxicol. Appl. Pharmacol.
    Arsenic and selenium are metalloids with similar chemical properties and metabolic fates. Inorganic arsenic (iAs...

  2. FREQUENCY-DEPENDENT CHANGES IN GAP JUNCTION FUNCTION IN PRIMARY HEPATOCYTES

    EPA Science Inventory

    FREQUENCY-DEPENDENT CHANGES IN GAP JUNCTION FUNCTION IN PRIMARY HEPATOCYTES. X. Wang1 *, D.E. Housel *, J. Page2, C.F. Blackmanl. 1 National Health and Environmental Effects Research Laboratory, USEPA, Research Triangle Park, North Carolina 27711 USA, 2Oakland, California USA
    ...

  3. EFFECT OF NONGENOTOXIC ENVIRONMENTAL CONTAMINATION ON CHOLESTEROL AND DNA SYNTHESIS IN CULTURED PRIMARY RAT HEPATOCYTES

    EPA Science Inventory

    The effect of certain reputedly non genotoxic agents on cholesterol and DNA synthesis was investigated in cultured rat primary hepatocytes and liver slices. epatocytes in culture were incubated for 48, 60, and 72 hrs with one of the following chemicals; namely, chloroform (CHCl3)...

  4. An Algorithm that Predicts the Viability and the Yield of Human Hepatocytes Isolated from Remnant Liver Pieces Obtained from Liver Resections

    PubMed Central

    Laubender, Rüdiger P.; Fröse, Natalja; Thasler, Reinhard M. K.; Schiergens, Tobias S.; Mansmann, Ulrich; Thasler, Wolfgang E.

    2014-01-01

    Isolated human primary hepatocytes are an essential in vitro model for basic and clinical research. For successful application as a model, isolated hepatocytes need to have a good viability and be available in sufficient yield. Therefore, this study aims to identify donor characteristics, intra-operative factors, tissue processing and cell isolation parameters that affect the viability and yield of human hepatocytes. Remnant liver pieces from tissue designated as surgical waste were collected from 1034 donors with informed consent. Human hepatocytes were isolated by a two-step collagenase perfusion technique with modifications and hepatocyte yield and viability were subsequently determined. The accompanying patient data was collected and entered into a database. Univariate analyses found that the viability and the yield of hepatocytes were affected by many of the variables examined. Multivariate analyses were then carried out to confirm the factors that have a significant relationship with the viability and the yield. It was found that the viability of hepatocytes was significantly decreased by the presence of fibrosis, liver fat and with increasing gamma-glutamyltranspeptidase activity and bilirubin content. Yield was significantly decreased by the presence of liver fat, septal fibrosis, with increasing aspartate aminotransferase activity, cold ischemia times and weight of perfused liver. However, yield was significantly increased by chemotherapy treatment. In conclusion, this study determined the variables that have a significant effect on the viability and the yield of isolated human hepatocytes. These variables have been used to generate an algorithm that can calculate projected viability and yield of isolated human hepatocytes. In this way, projected viability can be determined even before isolation of hepatocytes, so that donors that result in high viability and yield can be identified. Further, if the viability and yield of the isolated hepatocytes is lower

  5. Distribution and origin of the basement membrane component perlecan in rat liver and primary hepatocyte culture.

    PubMed Central

    Rescan, P. Y.; Loréal, O.; Hassell, J. R.; Yamada, Y.; Guillouzo, A.; Clément, B.

    1993-01-01

    Basement membranes contain three major components (ie collagen IV, laminin, and the heparan sulfate proteoglycan termed perlecan). Although the distribution and origin of both collagen IV and laminin have been well documented in the liver, perlecan has been poorly investigated, so far. We have studied the distribution and cellular origin of perlecan in rat livers in various conditions as well as in hepatocyte primary culture. By immunolocalization in both adult and 18-day-old fetal liver, perlecan was found in portal spaces, around central veins, and throughout the lobule. Immunoelectron microscopy revealed its presence at the level of basement membranes surrounding bile ducts and blood vessels, and in the space of Disse discontinuously interacting with hepatocyte microvilli. Precursors of perlecan were detected in the rough endoplasmic reticulum of bile duct cells and both vascular and sinusoidal endothelial cells. Both hepatocytes and Ito cells were negative. Northern-blot analysis confirmed the lack of appreciable expression of perlecan in hepatocytes isolated from either fetal or adult livers. In 18-month-diethylnitrosamine-treated rat liver, perlecan was abundant in neoplastic nodules. Electron microscopic investigation revealed an almost continuous layer of perlecan in the space of Disse and intracellular staining in sinusoidal endothelial cells, only. Perlecan mRNAs were detectable in malignant nodules, and absent in hepatocytes from nontumorous areas. Hepatocytes expressed high levels of perlecan mRNAs only when put in culture. This expression was reduced in conditions that allow improvement of hepatocyte survival and function (ie addition of corticoids, dimethylsulfoxide or nicotinamide to the medium, or in coculture with liver epithelial cells from biliary origin). Immunolocalization by light and electron microscopy showed that deposition of the proteoglycan occurred in coculture, in basement membranelike structures located around hepatocyte cords. In

  6. Oxidative stress is involved in Dasatinib-induced apoptosis in rat primary hepatocytes

    SciTech Connect

    Xue, Tao; Luo, Peihua; Zhu, Hong; Zhao, Yuqin; Wu, Honghai; Gai, Renhua; Wu, Youping; Yang, Bo; Yang, Xiaochun; He, Qiaojun

    2012-06-15

    Dasatinib, a multitargeted inhibitor of BCR–ABL and SRC kinases, exhibits antitumor activity and extends the survival of patients with chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL). However, some patients suffer from hepatotoxicity, which occurs through an unknown mechanism. In the present study, we found that Dasatinib could induce hepatotoxicity both in vitro and in vivo. Dasatinib reduced the cell viability of rat primary hepatocytes, induced the release of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) in vitro, and triggered the ballooning degeneration of hepatocytes in Sprague–Dawley rats in vivo. Apoptotic markers (chromatin condensation, cleaved caspase-3 and cleaved PARP) were detected to indicate that the injury induced by Dasatinib in hepatocytes in vitro was mediated by apoptosis. This result was further validated in vivo using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assays. Here we found that Dasatinib dramatically increased the level of reactive oxygen species (ROS) in hepatocytes, reduced the intracellular glutathione (GSH) content, attenuated the activity of superoxide dismutase (SOD), generated malondialdehyde (MDA), a product of lipid peroxidation, decreased the mitochondrial membrane potential, and activated nuclear factor erythroid 2-related factor 2 (Nrf2) and mitogen-activated protein kinases (MAPK) related to oxidative stress and survival. These results confirm that oxidative stress plays a pivotal role in Dasatinib-mediated hepatotoxicity. N-acetylcysteine (NAC), a typical antioxidant, can scavenge free radicals, attenuate oxidative stress, and protect hepatocytes against Dasatinib-induced injury. Thus, relieving oxidative stress is a viable strategy for reducing Dasatinib-induced hepatotoxicity. -- Highlights: ►Dasatinib shows potential hepatotoxicity both in vitro and in vivo. ►Apoptosis plays a vital role in Dasatinib

  7. The farnesoid X receptor induces fetuin-B gene expression in human hepatocytes

    PubMed Central

    Murakami, Takeshi; Walczak, Robert; Caron, Sandrine; Duhem, Christian; Vidal, Vincent; Darteil, Raphaël; Staels, Bart

    2007-01-01

    FXR (farnesoid X receptor), a nuclear receptor activated by BAs (bile acids), is a key factor in the regulation of BA, lipid and carbohydrate metabolism. The recent development of synthetic FXR agonists and knockout mouse models has accelerated the discovery of FXR target genes. In the present study, we identify human fetuin-B as a novel FXR target gene. Treatment with FXR agonists increased fetuin-B expression in human primary hepatocytes and in the human hepatoma HepG2 cell line. In contrast, fetuin-B expression was not responsive to FXR agonist treatment in murine primary hepatocytes. Fetuin-B induction by FXR agonist was abolished upon FXR knockdown by siRNA (small interfering RNA). In addition to the previously described P1 promoter, we show that the human fetuin-B gene is also transcribed from an alternative promoter, termed P2. Transcription via the P2 promoter was induced by FXR agonist treatment, whereas P1 promoter activity was not sensitive to FXR agonist treatment. Two putative FXR-response elements [IR-1 (inverted repeat-1)] were identified in the region –1.6 kb upstream of the predicted P2 transcriptional start site. Both motifs bound FXR–RXR (retinoid X receptor) complexes in vitro and were activated by FXR in transient transfection reporter assays. Mutations in the IR-1 sites abolished FXR–RXR binding and activation. Taken together, these results identify human fetuin-B as a new FXR target gene in human hepatocytes. PMID:17655523

  8. Toxicokinetics of acrylamide in primary rat hepatocytes: coupling to glutathione is faster than conversion to glycidamide.

    PubMed

    Watzek, Nico; Scherbl, Denise; Schug, Markus; Hengstler, Jan G; Baum, Matthias; Habermeyer, Michael; Richling, Elke; Eisenbrand, Gerhard

    2013-08-01

    Acrylamide (AA), classified as class 2A carcinogen (probably carcinogenic to humans) by the International Agency for Research on Cancer (IARC), is formed during heating of food from reducing carbohydrates and asparagine by Maillard reaction chemistry. After dietary uptake, AA is in part metabolically converted into the proximate genotoxic phase I metabolite glycidamide (GA). GA reacts with nucleophilic base positions in DNA, primarily forming N7-(2-carbamoyl-2-hydroxyethyl)guanine (N7-GA-Gua) adducts. In a competing phase II biotransformation pathway AA, as well as its phase I metabolite GA, is coupled to glutathione (GSH). The GSH coupling products are further biotransformed and excreted via urine as mercapturic acids (MA), N-acetyl-S-(2-carbamoylethyl)cysteine (AAMA), and N-acetyl-S-(2-hydroxy-2-carbamoylethyl)cysteine (GAMA). In the present study, hepatic biotransformation pathways and DNA adduct formation were studied in primary rat hepatocytes, incubated with AA (0.2-2,000 μM) for up to 24 h. Contents of AA-GSH, GA, AAMA, and GAMA were measured in the cell culture medium after solid phase extraction (SPE). N7-GA-Gua adducts in DNA of hepatocytes were determined by HPLC-ESI-MS/MS after lysis of the cells and neutral thermal hydrolysis. Formation of AA-GSH was linear with AA concentration and incubation time and became detectable already at 0.2 μM (4 h). In contrast to AA, GA was not detected before 16 h incubation at 10-fold higher AA concentration (2 μM). In summary, the rate of AA-GSH formation was found to be about 1.5-3 times higher than that of GA formation. N7-GA-Gua adducts were found only at the highest AA concentration tested (2,000 μM). PMID:23568512

  9. Assessment of mitochondrial dysfunction-related, drug-induced hepatotoxicity in primary rat hepatocytes.

    PubMed

    Liu, Cong; Sekine, Shuichi; Ito, Kousei

    2016-07-01

    Evidence that mitochondrial dysfunction plays a central role in drug-induced liver injury is rapidly accumulating. In contrast to physiological conditions, in which almost all adenosine triphosphate (ATP) in hepatocytes is generated in mitochondria via aerobic respiration, the high glucose content and limited oxygen supply of conventional culture systems force primary hepatocytes to generate most ATP via cytosolic glycolysis. Thus, such anaerobically poised cells are resistant to xenobiotics that impair mitochondrial function, and are not suitable to identify drugs with mitochondrial liabilities. In this study, primary rat hepatocytes were cultured in galactose-based medium, instead of the conventional glucose-based medium, and in hyperoxia to improve the reliance of energy generation on aerobic respiration. Activation of mitochondria was verified by diminished cellular lactate release and increased oxygen consumption. These conditions improved sensitivity to the mitochondrial complex I inhibitor rotenone. Since oxidative stress is also a general cause of mitochondrial impairment, cells were exposed to test compounds in the presence of transferrin to increase the generation of reactive oxygen species via increased uptake of iron. Finally, 14 compounds with reported mitochondrial liabilities were tested to validate this new drug-induced mitochondrial toxicity assay. Overall, the culture of primary rat hepatocytes in galactose, hyperoxia and transferrin is a useful model for the identification of mitochondrial dysfunction-related drug-induced hepatotoxicity. PMID:27095095

  10. A Systems Biology Study on NFκB Signaling in Primary Mouse Hepatocytes

    PubMed Central

    Pinna, Federico; Sahle, Sven; Beuke, Katharina; Bissinger, Michaela; Tuncay, Selcan; D’Alessandro, Lorenza A.; Gauges, Ralph; Raue, Andreas; Timmer, Jens; Klingmüller, Ursula; Schirmacher, Peter; Kummer, Ursula; Breuhahn, Kai

    2012-01-01

    The cytokine tumor necrosis factor-alpha (TNFα) is one of the key factors during the priming phase of liver regeneration as well as in hepatocarcinogenesis. TNFα activates the nuclear factor κ-light-chain-enhancer of activated B cells (NFκB) signaling pathway and contributes to the conversion of quiescent hepatocytes to activated hepatocytes that are able to proliferate in response to growth factor stimulation. Different mathematical models have been previously established for TNFα/NFκB signaling in the context of tumor cells. Combining these mathematical models with time-resolved measurements of expression and phosphorylation of TNFα/NFκB pathway constituents in primary mouse hepatocytes revealed that an additional phosphorylation step of the NFκB isoform p65 has to be considered in the mathematical model in order to sufficiently describe the dynamics of pathway activation in the primary cells. Also, we addressed the role of basal protein turnover by experimentally measuring the degradation rate of pivotal players in the absence of TNFα and including this information in the model. To elucidate the impact of variations in the protein degradation rates on TNFα/NFκB signaling on the overall dynamic behavior we used global sensitivity analysis that accounts for parameter uncertainties and showed that degradation and translation of p65 had a major impact on the amplitude and the integral of p65 phosphorylation. Finally, our mathematical model of TNFα/NFκB signaling was able to predict the time-course of the complex formation of p65 and of the inhibitor of NFκB (IκB) in primary mouse hepatocytes, which was experimentally verified. Hence, we here present a mathematical model for TNFα/NFκB signaling in primary mouse hepatocytes that provides an important basis to quantitatively disentangle the complex interplay of multiple factors in liver regeneration and tumorigenesis. PMID:23293603

  11. Species-specific toxicity of troglitazone on rats and human by gel entrapped hepatocytes

    SciTech Connect

    Shen, Chong; Meng, Qin; Zhang, Guoliang

    2012-01-01

    Troglitazone, despite passing preclinical trials on animals, was shortly withdrawn from market due to its severe hepatotoxicity in clinic. As rat hepatocyte monolayer consistently showed sensitive troglitazone toxicity as human hepatocyte monolayer in contrast to the species-specific toxicity in vivo, this paper utilized both hepatocytes in three-dimensional culture of gel entrapment to reflect the species difference on hepatotoxicity. Rat hepatocytes in gel entrapment did not show obvious cellular damage even under a long-term exposure for 21 days while gel entrapped human hepatocytes significantly displayed oxidative stress, steatosis, mitochondrial damage and cell death at a short exposure for 4 days. As a result, the detected species-specific toxicity of troglitazone between gel entrapped rat and human hepatocytes consisted well with the situation in vivo but was in a sharp contrast to the performance of two hepatocytes by monolayer culture. Such contradictory toxicity of rat hepatocytes between monolayer and gel entrapment culture could be explained by the fact that troglitazone was cleared more rapidly in gel entrapment than in monolayer culture. Similarly, the differential clearance of troglitazone in rat and human might also explain its species-specific toxicity. Therefore, gel entrapment of hepatocytes might serve as a platform for evaluation of drug toxicity at early stage of drug development by reducing costs, increasing the likelihood of clinical success and limiting human exposure to unsafe drugs. -- Highlights: ► Species-specific toxicity of troglitazone reflected by rat/human hepatocytes ► 3D hepatocytes in 21 days’ long-term culture used for drug hepatotoxicity ► Oversensitive toxicity in hepatocyte monolayer by slow troglitazone clearance.

  12. Hepatocyte growth factor enhances the barrier function in primary cultures of rat brain microvascular endothelial cells.

    PubMed

    Yamada, Narumi; Nakagawa, Shinsuke; Horai, Shoji; Tanaka, Kunihiko; Deli, Maria A; Yatsuhashi, Hiroshi; Niwa, Masami

    2014-03-01

    The effects of hepatocyte growth factor (HGF) on barrier functions were investigated by a blood-brain barrier (BBB) in vitro model comprising a primary culture of rat brain capillary endothelial cells (RBEC). In order to examine the response of the peripheral endothelial cells to HGF, human umbilical vascular endothelial cells (HUVEC) and human dermal microvascular endothelial cells (HMVEC) were also treated with HGF. HGF decreased the permeability of RBEC to sodium fluorescein and Evans blue albumin, and dose-dependently increased transendothelial electrical resistance (TEER) in RBEC. HGF altered the immunochemical staining pattern of F-actin bands and made ZO-1 staining more distinct on the linear cell borders in RBEC. In contrast, HGF increased sodium fluorescein and Evans blue albumin permeability in HMVEC and HUVEC, and decreased TEER in HMVEC. In HMVEC, HGF reduced cortical actin bands and increased stress fiber density, and increased the zipper-like appearance of ZO-1 staining. Western blot analysis showed that HGF significantly increased the amount of ZO-1 and VE-cadherin. HGF seems to act on the BBB to strengthen BBB integrity. These findings indicated that cytoskeletal rearrangement and cell-cell adhesion, such as through VE-cadherin and ZO-1, are candidate mechanisms for the influence of HGF on the BBB. The possibility that HGF has therapeutic significance in protecting the BBB from damage needs to be considered. PMID:24370951

  13. Evaluation of a carp primary hepatocyte culture system for screening chemicals for oestrogenic activity.

    PubMed

    Bickley, L K; Lange, A; Winter, M J; Tyler, C R

    2009-09-14

    The presence of endocrine disrupting chemicals (EDCs) in the environment has driven the development of screening and testing assays to both identify chemicals with hormonal activity and evaluate their potential to cause adverse effects. As the number of animals used for research and regulatory purposes rises, and set against a desire to reduce animal testing, there is increased emphasis on the development and application of in vitro techniques to evaluate chemical risks to the environment. Induction of vitellogenin (VTG) in isolated fish liver cells has been used successfully to identify a wide range of EDCs, including both natural and synthetic oestrogens and a variety of other xenoestrogens. However, the vitellogenic response reported for hepatocytes in culture has been shown to vary widely, making comparisons between studies difficult. The work presented in this paper explored the variability of the vitellogenic response in primary cultures of common carp (Cyprinus carpio) hepatocytes following exposure to the model oestrogenic compound, 17beta-oestradiol (E2). As expected, variability in the vitellogenic response was observed, both in terms of the sensitivity and magnitude of VTG induction, for hepatocytes isolated from different fish. An apparent difference was observed in the response of isolated hepatocytes based on the sex of the donor fish; maximum levels of E2-stimulated VTG synthesis in hepatocytes derived from females appeared higher (1962 ng mL(-1)+/-487 [n=9] compared with 1194 ng mL(-1)+/-223 for hepatocytes from males [n=9]) and EC(50) values lower (1.61+/-0.4 microM E2 for females and 2.12+/-0.2 microM E2 for males). However, these differences were not statistically significant, likely in part due to the variation observed in the vitellogenic response. In particular, hepatocytes derived from female fish showed more variation than their male counterparts (the co-efficient of variation for females was 77% compared to 28% for males). Despite the

  14. Effects of Trichostatin A on drug uptake transporters in primary rat hepatocyte cultures.

    PubMed

    Ramboer, Eva; Rogiers, Vera; Vanhaecke, Tamara; Vinken, Mathieu

    2015-01-01

    The present study was set up to investigate the effects of Trichostatin A (TSA), a prototypical epigenetic modifier, on the expression and activity of hepatic drug uptake transporters in primary cultured rat hepatocytes. To this end, the expression of the sinusoidal transporters sodium-dependent taurocholate cotransporting polypeptide (Ntcp) and organic anion transporting polypeptide 4 (Oatp4) was monitored by real-time quantitative reverse transcriptase polymerase chain reaction analysis and immunoblotting. The activity of the uptake transporters was analyzed using radiolabeled substrates and chemical inhibitors. Downregulation of the expression and activity of Oatp4 and Ntcp was observed as a function of the cultivation time and could not be counteracted by TSA. In conclusion, the epigenetic modifier TSA does not seem to exert a positive effect on the expression and activity of the investigated uptake transporters in primary rat hepatocyte cultures. PMID:26648816

  15. Hepatoprotective constituents of Firmiana simplex stem bark against ethanol insult to primary rat hepatocytes

    PubMed Central

    Kim, Jung Wha; Yang, Heejung; Cho, Namki; Kim, Bitnarae; Kim, Young Choong; Sung, Sang Hyun

    2015-01-01

    Background: Ethanol causes hepatic cellular damage by alterations in biological functions. This study evaluated the hepatoprotective potential of the methanolic extract originating from Firmiana simplex (Sterculiaceae) stem bark against the ethanol-induced hepatotoxicity in rat primary hepatocytes. Materials and Methods: The extract of F. simplex stem bark was successively fractionated into n-hexane, chloroform, ethyl acetate (EtOAc), and n-butanol. Column chromatography with silica gel and sephadex LH-20 was used to isolate the EtOAc fraction. Rat primary hepatocytes were cultured to study the hepatoprotective activity of isolated substances against ethanol-induced toxicity. Intracellular reactive oxygen species (ROS) levels, the antioxidant activities of glutathione reductase (GR) and glutathione peroxidase (GSH-PX) enzymes, and the GSH content were measured to examine the antioxidative property of the isolated compounds. Results: Two flavonoid glycosides, quercitrin (1) and tamarixetin 3-O-rhamnopyranoside (2), were isolated from the active EtOAc fraction. Compound 1 significantly protected rat primary hepatocytes against ethanol-induced oxidative stress by reducing the intracellular ROS level and preserving antioxidative defense systems such as GR, GSH-PX, and total GSH. Conclusion: This is the first report on the hepatoprotective activities of the extract of F. simplex. The EtOAc fraction of F. simplex stem bark and its major constituent quercitrin (1) could function as hepatoprotective agents to attenuate the development of alcoholic liver disease. PMID:25709211

  16. Asialoglycoprotein receptor 1 is a specific cell-surface marker for isolating hepatocytes derived from human pluripotent stem cells.

    PubMed

    Peters, Derek T; Henderson, Christopher A; Warren, Curtis R; Friesen, Max; Xia, Fang; Becker, Caroline E; Musunuru, Kiran; Cowan, Chad A

    2016-05-01

    Hepatocyte-like cells (HLCs) are derived from human pluripotent stem cells (hPSCs) in vitro, but differentiation protocols commonly give rise to a heterogeneous mixture of cells. This variability confounds the evaluation of in vitro functional assays performed using HLCs. Increased differentiation efficiency and more accurate approximation of the in vivo hepatocyte gene expression profile would improve the utility of hPSCs. Towards this goal, we demonstrate the purification of a subpopulation of functional HLCs using the hepatocyte surface marker asialoglycoprotein receptor 1 (ASGR1). We analyzed the expression profile of ASGR1-positive cells by microarray, and tested their ability to perform mature hepatocyte functions (albumin and urea secretion, cytochrome activity). By these measures, ASGR1-positive HLCs are enriched for the gene expression profile and functional characteristics of primary hepatocytes compared with unsorted HLCs. We have demonstrated that ASGR1-positive sorting isolates a functional subpopulation of HLCs from among the heterogeneous cellular population produced by directed differentiation. PMID:27143754

  17. Effect of iprodione, a dicarboximide fungicide, on primary cultured rainbow trout (Oncorhynchus mykiss) hepatocytes.

    PubMed

    Radice, S; Ferraris, M; Marabini, L; Grande, S; Chiesara, E

    2001-09-01

    As is known from literature, iprodione, a dicarboximide fungicide, has a highly specific action, with a capacity to cause oxidative damage through production of free oxygen radicals (ROS), but it does not appear to be species selective. Since this substance is able to diffuse in water, evaluation of its capacity to induce oxidative damage in an aquatic organism such as the rainbow trout (Oncorhynchus mykiss) was considered of particular interest. A study was, therefore, undertaken to investigate the effect of iprodione on free radicals (ROS) and malondialdehyde (MDA) production, reduced glutathione (GSH) content and catalase activity (CAT), in primary cultured trout hepatocytes, following treatment with 0.2, 0.3 and 0.4 mM concentrations for a 24-h period. The iprodione 0.3 and 0.4 mM concentrations increased both ROS and MDA production and decreased GSH content and CAT activity. These results suggest that iprodione is able to produce oxidative damage in primary cultured fish hepatocytes, thus confirming that its action is specific, but not species selective. It is also well known that ROS production in fungi is due to interaction with the flavin enzyme NADPH cytochrome c reductase to the extent that the normal electron flow from NADPH to cytochrome c is blocked. In contrast, we observed that, in primary cultured trout hepatocytes, iprodione appears to have no effect on NADPH cytochrome c reductase activity. It is, therefore, possible to presume that the mechanism of oxidative damage in trout hepatocytes differs from that observed in fungi. Moreover, our experiments also demonstrate that iprodione is able to induce "in vitro" CYP1A1, leading to the conclusion that the production of ROS is due to this phenomenon. PMID:11451425

  18. Immortalization of Human Fetal Hepatocyte by Ectopic Expression of Human Telomerase Reverse Transcriptase, Human Papilloma Virus (E7) and Simian Virus 40 Large T (SV40 T) Antigen Towards Bioartificial Liver Support

    PubMed Central

    Giri, Shibashish; Bader, Augustinus

    2014-01-01

    Background Generation of genetically stable and non-tumoric immortalization cell line from primary cells would be enormously useful for research and therapeutic purposes, but progress towards this goal has so far been limited. It is now universal acceptance that immortalization of human fetal hepatocytes based on recent advances of telomerase biology and oncogene, lead to unlimited population doubling could be the possible source for bioartificial liver device. Methods Immortalization of human fetal hepatocytes cell line by ectopic expression of human telomerase reverse transcriptase (hTERT), human papilloma virus gene (E7) and simian virus 40 large T (SV40 T) antigens is main goal of present study. We used an inducible system containing human telomerase and E7, both of which are cloned into responder constructs controlled by doxycycline transactivator. We characterized the immortalized human fetal hepatocyte cells by analysis of green fluorescent cells (GFP) positive cells using flow cytometry (FACs) cell sorting and morphology, proliferative rate and antigen expression by immunohistochemical analysis. In addition to we analysized lactate formation, glucose consumption, albumin secretion and urea production of immortalized human fetal hepatocyte cells. Results After 25 attempts for transfection of adult primary hepatocytes by human telomerase and E7 to immortalize them, none of the transfection systems resulted in the production of a stable, proliferating cell line. Although the transfection efficiency was more than 70% on the first day, the vast majority of the transfected hepatocytes lost their signal within the first 5–7 days. The remaining transfected hepatocytes persisted for 2–4 weeks and divided one or two times without forming a clone. After 10 attempts of transfection human fetal hepatocytes using the same transfection system, we obtained one stable human fetal hepatocytes cell line which was able albumin secretion urea production and glucose

  19. Conjugated bile acids activate the sphingosine-1-phosphate receptor 2 in primary rodent hepatocytes.

    PubMed

    Studer, Elaine; Zhou, Xiqiao; Zhao, Renping; Wang, Yun; Takabe, Kazuaki; Nagahashi, Masayuki; Pandak, William M; Dent, Paul; Spiegel, Sarah; Shi, Ruihua; Xu, Weiren; Liu, Xuyuan; Bohdan, Pat; Zhang, Luyong; Zhou, Huiping; Hylemon, Phillip B

    2012-01-01

    Bile acids have been shown to be important regulatory molecules for cells in the liver and gastrointestinal tract. They can activate various cell signaling pathways including extracellular regulated kinase (ERK)1/2 and protein kinase B (AKT) as well as the G-protein-coupled receptor (GPCR) membrane-type bile acid receptor (TGR5/M-BAR). Activation of the ERK1/2 and AKT signaling pathways by conjugated bile acids has been reported to be sensitive to pertussis toxin (PTX) and dominant-negative Gα(i) in primary rodent hepatocytes. However, the GPCRs responsible for activation of these pathways have not been identified. Screening GPCRs in the lipid-activated phylogenetic family (expressed in HEK293 cells) identified sphingosine-1-phosphate receptor 2 (S1P(2) ) as being activated by taurocholate (TCA). TCA, taurodeoxycholic acid (TDCA), tauroursodeoxycholic acid (TUDCA), glycocholic acid (GCA), glycodeoxycholic acid (GDCA), and S1P-induced activation of ERK1/2 and AKT were significantly inhibited by JTE-013, a S1P(2) antagonist, in primary rat hepatocytes. JTE-013 significantly inhibited hepatic ERK1/2 and AKT activation as well as short heterodimeric partner (SHP) mRNA induction by TCA in the chronic bile fistula rat. Knockdown of the expression of S1P(2) by a recombinant lentivirus encoding S1P(2) shRNA markedly inhibited the activation of ERK1/2 and AKT by TCA and S1P in rat primary hepatocytes. Primary hepatocytes prepared from S1P(2) knock out (S1P(2) (-/-) ) mice were significantly blunted in the activation of the ERK1/2 and AKT pathways by TCA. Structural modeling of the S1P receptors indicated that only S1P(2) can accommodate TCA binding. In summary, all these data support the hypothesis that conjugated bile acids activate the ERK1/2 and AKT signaling pathways primarily through S1P(2) in primary rodent hepatocytes. PMID:21932398

  20. Hepatocyte cell therapy in liver disease.

    PubMed

    Bartlett, David Christopher; Newsome, Philip N

    2015-01-01

    Liver disease is a leading cause of morbidity and mortality. Liver transplantation remains the only proven treatment for end-stage liver failure but is limited by the availability of donor organs. Hepatocyte cell therapy, either with bioartificial liver devices or hepatocyte transplantation, may help address this by delaying or preventing liver transplantation. Early clinical studies have shown promising results, however in most cases, the benefit has been short lived and so further research into these therapies is required. Alternative sources of hepatocytes, including stem cell-derived hepatocytes, are being investigated as the isolation of primary human hepatocytes is limited by the same shortage of donor organs. This review summarises the current clinical experience of hepatocyte cell therapy together with an overview of possible alternative sources of hepatocytes. Current and future areas for research that might lead towards the realisation of the full potential of hepatocyte cell therapy are discussed. PMID:26212798

  1. Regulation of drug transporter expression by oncostatin M in human hepatocytes.

    PubMed

    Le Vee, Marc; Jouan, Elodie; Stieger, Bruno; Lecureur, Valérie; Fardel, Olivier

    2011-08-01

    The cytokine oncostatin M (OSM) is a member of the interleukin (IL)-6 family, known to down-regulate expression of drug metabolizing cytochromes P-450 in human hepatocytes. The present study was designed to determine whether OSM may also impair expression of sinusoidal and canalicular drug transporters, which constitute important determinants of drug hepatic clearance. Exposure of primary human hepatocytes to OSM down-regulated mRNA levels of major sinusoidal solute carrier (SLC) influx transporters, including sodium-taurocholate co-transporting polypeptide (NTCP), organic anion transporting polypeptide (OATP) 1B1, OATP1B3, OATP2B1, organic cation transporter 1 and organic anion transporter 2. OSM also repressed mRNA expressions of ATP binding cassette (ABC) efflux transporters such as multidrug resistance protein (MRP) 2/ABCC2 and breast cancer resistance protein/ABCG2, without however impairing those of multidrug resistance gene 1/P-glycoprotein/ABCB1, MRP3/ABCC3, MRP4/ABCC4 and bile salt export pump/ABCB11. The cytokine concomitantly reduced NTCP, OATP1B1, OATP2B1 and ABCG2 protein expression and NTCP and OATP transport activities. OSM effects towards transporters were found to be dose-dependent and highly correlated with those of IL-6, but not with those of other inflammatory cytokines such as tumor necrosis factor-α or interferon-γ. In addition, OSM-mediated repression of some transporters such as NTCP, OATP1B1 and OATP2B1, was counteracted by knocking-down expression of the type II OSM receptor subunits through siRNA transfection. This OSM-mediated down-regulation of drug SLC transporters and ABCG2 in human hepatocytes may contribute to alterations of pharmacokinetics in patients suffering from diseases associated with increased production of OSM. PMID:21570956

  2. Trichostatin A, a critical factor in maintaining the functional differentiation of primary cultured rat hepatocytes

    SciTech Connect

    Henkens, Tom . E-mail: Tom.Henkens@vub.ac.be; Papeleu, Peggy; Elaut, Greetje; Vinken, Mathieu; Rogiers, Vera; Vanhaecke, Tamara

    2007-01-01

    Histone deacetylase inhibitors (HDI) have been shown to increase differentiation-related gene expression in several tumor-derived cell lines by hyperacetylating core histones. Effects of HDI on primary cultured cells, however, have hardly been investigated. In the present study, the ability of trichostatin A (TSA), a prototype hydroxamate HDI, to counteract the loss of liver-specific functions in primary rat hepatocyte cultures has been investigated. Upon exposure to TSA, it was found that the cell viability of the cultured hepatocytes and their albumin secretion as a function of culture time were increased. TSA-treated hepatocytes also better maintained cytochrome P450 (CYP)-mediated phase I biotransformation capacity, whereas the activity of phase II glutathione S-transferases (GST) was not affected. Western blot and qRT-PCR analysis of CYP1A1, CYP2B1 and CYP3A11 protein and mRNA levels, respectively, further revealed that TSA acts at the transcriptional level. In addition, protein expression levels of the liver-enriched transcription factors (LETFs) hepatic nuclear factor 4 alpha (HNF4{alpha}) and CCAAT/enhancer binding protein alpha (C/EBP{alpha}) were accordingly increased by TSA throughout culture time. In conclusion, these findings indicate that TSA plays a major role in the preservation of the differentiated hepatic phenotype in culture. It is suggested that the effects of TSA on CYP gene expression are mediated via controlling the expression of LETFs.

  3. Turnover of inositol pentakisphosphates, inositol hexakisphosphate and diphosphoinositol polyphosphates in primary cultured hepatocytes.

    PubMed Central

    Glennon, M C; Shears, S B

    1993-01-01

    We have used a non-transformed cell model, the primary cultured hepatocyte, to explore the turnover of inositol hexakisphosphate, multiple isomers of inositol pentakisphosphate and two novel diphosphoinositol polyphosphates. All of these compounds gradually accumulated radioactivity throughout a 70 h period of labelling with [3H]inositol. However, a rapid metabolic rate was revealed upon inhibition of diphosphoinositol polyphosphate biphosphatase(s) with 1 mM fluoride for 40 min: this treatment elevated levels of [3H]diphosphoinositol polyphosphates up to 10-fold, indicating that their cellular pools were normally turning over at least 10 times every 40 min. This was accompanied by a turnover of about 10% of the pool of inositol hexakisphosphate. Control experiments established that 200 nM vasopressin brought about a typical activation of phospholipase C in hepatocytes after 62 h of primary culture. This agonist treatment did not affect steady-state levels of [3H]inositol pentakisphosphates, [3H]inositol hexakisphosphate or [3H]diphosphoinositol polyphosphates. However, prolonged treatment of hepatocytes with 2 microM thapsigargin reduced steady-state levels of [3H]diphosphoinositol polyphosphates by 50-70%. This effect of thapsigargin was also observed in the presence of fluoride, indicating that thapsigargin inhibited the rate of synthesis of diphosphoinositol polyphosphates. PMID:8343137

  4. The cytochrome P450 inhibitor SKF-525A disrupts autophagy in primary rat hepatocytes.

    PubMed

    Luo, Yong; Yang, Xi; Shi, Qiang

    2016-08-01

    The cytochrome P450 (CYP) inhibitor SKF-525A is commonly used to study drug metabolism and toxicity, particularly hepatotoxicity. By using Western blot and immunofluorescence staining, we unexpectedly found that SKF-525A at 2-20 μM caused remarkable accumulation of microtubule-associated protein light chain 3 II (LC3-II) in primary rat hepatocytes at 1, 4 and 24 h, indicating that autophagy was disrupted. SKF-525A showed no effects on chloroquine induced LC3-II accumulation, suggesting that autophagic flux was blocked, which is further supported by the increased level of the p62 protein after SKF-525A treatment. SKF-525A did not affect proteasome activities or gene expression of LC3-II or p62. Immunofluorescence of green fluorescent protein fused lysosomal-associated membrane protein 1 (LAMP1, a specific protein marker for lysosomes) and LC3-II showed that co-localization of these two proteins was partially abolished by SKF-525A, indicating that autophagosome-lysosome fusion was blocked. The other five CYP inhibitors, metyrapone, 1-aminobenzotriazole, alpha-naphthoflavone, ticlopidine, and ketoconazole, showed no effects in parallel experiments. These findings provide novel insights into the mechanisms by which various CYP inhibitors differentially affect a same drug's toxicity in hepatocytes. The data also indicate that SKF-525A is not an ideal chemical inhibitor for probing the relation between CYP mediated metabolism and toxicity in primary hepatocytes. PMID:26964495

  5. Utilization of supplemental methionine sources by primary cultures of chick hepatocytes

    SciTech Connect

    Dibner, J.J.

    1983-10-01

    Utilization of 2-hydroxy-4-(methylthio) butanoic acid (HMB) as a substrate for protein synthesis was studied by using primary cultures of chick liver cells. Cultures were prepared by enzymatic dissociation of livers from week old Hubbard broiler chicks and were maintained for 4 days under nonproliferative conditions. Hepatocyte differentiation was verified by using dexamethasone induction of tyrosine aminotransferase activity. Conversion of (14C)HMB to L-methionine was shown by chromatographic analysis of hepatocyte protein hydrolysate and incorporation into protein was proven by cycloheximide inhibition of synthesis. When incorporation of HMB was compared to that of DL-methionine (DLM) equimolar quantities of the two sources were found in liver cell protein. These results support, at a cellular level, the conclusion that HMB and DLM are biochemically equivalent sources of methionine for protein synthesis.

  6. Micropatterned cell-cell interactions enable functional encapsulation of primary hepatocytes in hydrogel microtissues.

    PubMed

    Li, Cheri Y; Stevens, Kelly R; Schwartz, Robert E; Alejandro, Brian S; Huang, Joanne H; Bhatia, Sangeeta N

    2014-08-01

    Drug-induced liver injury is a major cause of drug development failures and postmarket withdrawals. In vitro models that incorporate primary hepatocytes have been shown to be more predictive than model systems which rely on liver microsomes or hepatocellular carcinoma cell lines. Methods to phenotypically stabilize primary hepatocytes ex vivo often rely on mimicry of hepatic microenvironmental cues such as cell-cell interactions and cell-matrix interactions. In this work, we sought to incorporate phenotypically stable hepatocytes into three-dimensional (3D) microtissues, which, in turn, could be deployed in drug-screening platforms such as multiwell plates and diverse organ-on-a-chip devices. We first utilize micropatterning on collagen I to specify cell-cell interactions in two-dimensions, followed by collagenase digestion to produce well-controlled aggregates for 3D encapsulation in polyethylene glycol (PEG) diacrylate. Using this approach, we examined the influence of homotypic hepatocyte interactions and composition of the encapsulating hydrogel, and achieved the maintenance of liver-specific function for over 50 days. Optimally preaggregated structures were subsequently encapsulated using a microfluidic droplet-generator to produce 3D microtissues. Interactions of engineered hepatic microtissues with drugs was characterized by flow cytometry, and yielded both induction of P450 enzymes in response to prototypic small molecules and drug-drug interactions that give rise to hepatotoxicity. Collectively, this study establishes a pipeline for the manufacturing of 3D hepatic microtissues that exhibit stabilized liver-specific functions and can be incorporated into a wide array of emerging drug development platforms. PMID:24498910

  7. Micropatterned Cell–Cell Interactions Enable Functional Encapsulation of Primary Hepatocytes in Hydrogel Microtissues

    PubMed Central

    Li, Cheri Y.; Stevens, Kelly R.; Schwartz, Robert E.; Alejandro, Brian S.; Huang, Joanne H.

    2014-01-01

    Drug-induced liver injury is a major cause of drug development failures and postmarket withdrawals. In vitro models that incorporate primary hepatocytes have been shown to be more predictive than model systems which rely on liver microsomes or hepatocellular carcinoma cell lines. Methods to phenotypically stabilize primary hepatocytes ex vivo often rely on mimicry of hepatic microenvironmental cues such as cell–cell interactions and cell–matrix interactions. In this work, we sought to incorporate phenotypically stable hepatocytes into three-dimensional (3D) microtissues, which, in turn, could be deployed in drug-screening platforms such as multiwell plates and diverse organ-on-a-chip devices. We first utilize micropatterning on collagen I to specify cell–cell interactions in two-dimensions, followed by collagenase digestion to produce well-controlled aggregates for 3D encapsulation in polyethylene glycol (PEG) diacrylate. Using this approach, we examined the influence of homotypic hepatocyte interactions and composition of the encapsulating hydrogel, and achieved the maintenance of liver-specific function for over 50 days. Optimally preaggregated structures were subsequently encapsulated using a microfluidic droplet-generator to produce 3D microtissues. Interactions of engineered hepatic microtissues with drugs was characterized by flow cytometry, and yielded both induction of P450 enzymes in response to prototypic small molecules and drug–drug interactions that give rise to hepatotoxicity. Collectively, this study establishes a pipeline for the manufacturing of 3D hepatic microtissues that exhibit stabilized liver-specific functions and can be incorporated into a wide array of emerging drug development platforms. PMID:24498910

  8. Primary hepatocyte cultures for pharmaco-toxicological studies: at the busy crossroad of various anti-dedifferentiation strategies.

    PubMed

    Fraczek, J; Bolleyn, J; Vanhaecke, T; Rogiers, V; Vinken, M

    2013-04-01

    Continuously increasing understanding of the molecular triggers responsible for the onset of diseases, paralleled by an equally dynamic evolution of chemical synthesis and screening methods, offers an abundance of pharmacological agents with a potential to become new successful drugs. However, before patients can benefit of newly developed pharmaceuticals, stringent safety filters need to be applied to weed out unfavourable drug candidates. Cost effectiveness and the need to identify compound liabilities, without exposing humans to unnecessary risks, has stimulated the shift of the safety studies to the earliest stages of drug discovery and development. In this regard, in vivo relevant organotypic in vitro models have high potential to revolutionize the preclinical safety testing. They can enable automation of the process, to match the requirements of high-throughput screening approaches, while satisfying ethical considerations. Cultures of primary hepatocytes became already an inherent part of the preclinical pharmaco-toxicological testing battery, yet their routine use, particularly for long-term assays, is limited by the progressive deterioration of liver-specific features. The availability of suitable hepatic and other organ-specific in vitro models is, however, of paramount importance in the light of changing European legal regulations in the field of chemical compounds of different origin, which gradually restrict the use of animal studies for safety assessment, as currently witnessed in cosmetic industry. Fortunately, research groups worldwide spare no effort to establish hepatic in vitro systems. In the present review, both classical and innovative methodologies to stabilize the in vivo-like hepatocyte phenotype in culture of primary hepatocytes are presented and discussed. PMID:23242478

  9. Screening for Drug-Induced Hepatotoxicity in Primary Mouse Hepatocytes Using Acetaminophen, Amiodarone, and Cyclosporin A as Model Compounds: An Omics-Guided Approach

    PubMed Central

    Van Summeren, Anke; Renes, Johan; Lizarraga, Daneida; Bouwman, Freek G.; Noben, Jean-Paul; van Delft, Joost H. M.; Kleinjans, Jos C. S.

    2013-01-01

    Abstract Drug-induced hepatotoxicity is a leading cause of attrition for candidate pharmaceuticals in development. New preclinical screening methods are crucial to predict drug toxicity prior to human studies. Of all in vitro hepatotoxicity models, primary human hepatocytes are considered as ‘the gold standard.’ However, their use is hindered by limited availability and inter-individual variation. These barriers may be overcome by using primary mouse hepatocytes. We used differential in gel electrophoresis (DIGE) to study large-scale protein expression of primary mouse hepatocytes. These hepatocytes were exposed to three well-defined hepatotoxicants: acetaminophen, amiodarone, and cyclosporin A. Each hepatotoxicant induces a different hepatotoxic phenotype. Based on the DIGE results, the mRNA expression levels of deregulated proteins from cyclosporin A-treated cells were also analyzed. We were able to distinguish cyclosporin A from controls, as well as acetaminophen and amiodarone-treated samples. Cyclosporin A induced endoplasmic reticulum (ER) stress and altered the ER-Golgi transport. Moreover, liver carboxylesterase and bile salt sulfotransferase were differentially expressed. These proteins were associated with a protective adaptive response against cyclosporin A-induced cholestasis. The results of this study are comparable with effects in HepG2 cells. Therefore, we suggest both models can be used to analyze the cholestatic properties of cyclosporin A. Furthermore, this study showed a conserved response between primary mouse hepatocytes and HepG2 cells. These findings collectively lend support for use of omics strategies in preclinical toxicology, and might inform future efforts to better link preclinical and clinical research in rational drug development. PMID:23308384

  10. Human monocyte-derived cells with individual hepatocyte characteristics: a novel tool for personalized in vitro studies.

    PubMed

    Benesic, Andreas; Rahm, Nora L; Ernst, Samuel; Gerbes, Alexander L

    2012-06-01

    Gender, ethnicity and individual differences in hepatic metabolism have major impact on individual drug response, adverse events and attrition rate during drug development. Therefore, there is an urgent need for reliable test systems based on human cells. Yet, the use of primary human hepatocytes (PHHs) is restricted by limited availability, invasive preparation and short-term stability in culture. All other cellular approaches proposed so far have major disadvantages. We investigated whether peripheral human monocytes after cultivation according to our novel protocol (monocyte-derived hepatocyte-like cells (MH cells)) can serve as an in vitro model for hepatocyte metabolism. Enzyme activities, synthesis parameters (coagulation factor VII and urea) and cytochrome (CY) P450 activities and induction were investigated. Furthermore, MH cells were compared with PHH from the same donor. Using our protocol, we could generate cells that exhibit hepatocyte-like properties: These cells show 71±9% of specific ALT activity, 41±3% of CYP3A4 activity and 65±13% of factor VII secretion when compared with PHHs. Consequently, CYP-mediated acetaminophen toxicity and drug interactions could be shown. Moreover, the investigated parameters were stable in culture over at least 4 weeks. Furthermore, MH cells retain gender-specific and donor-specific CYP activities and toxicity profiles, respectively. MH cells show quantitative and qualitative approximation to human hepatocytes concerning CYP-metabolism and toxicity. Our data support individual prediction of toxicity and CYP metabolism. MH cells are a novel tool to investigate long-term hepatic toxicity, metabolism and drug interactions. PMID:22469698

  11. Polarized location of SLC and ABC drug transporters in monolayer-cultured human hepatocytes.

    PubMed

    Le Vee, Marc; Jouan, Elodie; Noel, Gregory; Stieger, Bruno; Fardel, Olivier

    2015-08-01

    Human hepatocytes cultured in a monolayer configuration represent a well-established in vitro model in liver toxicology, notably used in drug transporter studies. Polarized status of drug transporters, i.e., their coordinated location at sinusoidal or canalicular membranes, remains however incompletely documented in these cultured hepatocytes. The present study was therefore designed to analyze transporter expression and location in such cells. Most of drug transporters were first shown to be present at notable mRNA levels in monolayer-cultured human hepatocytes. Cultured human hepatocytes, which morphologically exhibited bile canaliculi-like structures, were next demonstrated, through immunofluorescence staining, to express the influx transporters organic anion transporting polypeptide (OATP) 1B1, OATP2B1 and organic cation transporter (OCT) 1 and the efflux transporter multidrug resistance-associated protein (MRP) 3 at their sinusoidal pole. In addition, the efflux transporters P-glycoprotein and MRP2 were detected at the canalicular pole of monolayer-cultured human hepatocytes. Moreover, canalicular secretion of reference substrates for the efflux transporters bile salt export pump, MRP2 and P-glycoprotein as well as sinusoidal drug transporter activities were observed. This polarized and functional expression of drug transporters in monolayer-cultured human hepatocytes highlights the interest of using this human in vitro cell model in xenobiotic transport studies. PMID:25862123

  12. Functionally Enhanced Human Stem Cell Derived Hepatocytes in Galactosylated Cellulosic Sponges for Hepatotoxicity Testing.

    PubMed

    Tasnim, Farah; Toh, Yi-Chin; Qu, Yinghua; Li, Huan; Phan, Derek; Narmada, Balakrishnan C; Ananthanarayanan, Abhishek; Mittal, Nikhil; Meng, Ryan Q; Yu, Hanry

    2016-06-01

    Pluripotent stem cell derived hepatocyte-like cells (hPSC-HLCs) are an attractive alternative to primary human hepatocytes (PHHs) used in applications ranging from therapeutics to drug safety testing studies. It would be critical to improve and maintain mature hepatocyte functions of the hPSC-HLCs, especially for long-term studies. If 3D culture systems were to be used for such purposes, it would be important that the system can support formation and maintenance of optimal-sized spheroids for long periods of time, and can also be directly deployed in liver drug testing assays. We report the use of 3-dimensional (3D) cellulosic scaffold system for the culture of hPSC-HLCs. The scaffold has a macroporous network which helps to control the formation and maintenance of the spheroids for weeks. Our results show that culturing hPSC-HLCs in 3D cellulosic scaffolds increases functionality, as demonstrated by improved urea production and hepatic marker expression. In addition, hPSC-HLCs in the scaffolds exhibit a more mature phenotype, as shown by enhanced cytochrome P450 activity and induction. This enables the system to show a higher sensitivity to hepatotoxicants and a higher degree of similarity to PHHs when compared to conventional 2D systems. These results suggest that 3D cellulosic scaffolds are ideal for the long-term cultures needed to mature hPSC-HLCs. The mature hPSC-HLCs with improved cellular function can be continually maintained in the scaffolds and directly used for hepatotoxicity assays, making this system highly attractive for drug testing applications. PMID:27157693

  13. Protectivity of blue honeysuckle extract against oxidative human endothelial cells and rat hepatocyte damage.

    PubMed

    Palíková, Irena; Valentová, Katerina; Oborná, Ivana; Ulrichová, Jitka

    2009-08-12

    The effect of Lonicera caerulea L. (blue honeysuckle) phenolic fraction (18.5% anthocyanins) on cell viability and against oxidative damage in low density lipoproteins (oxLDL), in rat microsomes and in primary cultures of rat hepatocytes and human umbilical vein endothelial cells (HUVEC), was tested. The phenolic fraction was nontoxic to rat hepatocytes and HUVEC at tested concentrations (1-1000 microg/mL) and time intervals up to 24 h inclusive. Phenolic fraction inhibited rat liver microsome peroxidation, induced by tert-butyl hydroperoxide (tBH), with IC(50) values of 160 +/- 20 microg/mL. The fraction at 0.5, 1.0, and 2.0 microg/mL delayed LDL oxidation, induced by Cu(2+), by 130 +/- 20%, 200 +/- 30%, and 400 +/- 10%, respectively. The treatment of HUVEC with oxidatively modified LDL induced an increase in lactate dehydrogenase (LDH) leakage and thiobarbituric acid reactive substances (TBARS) formation, and resulted in lower formazan formation from 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) uptake, most pronounced for 200 microg/mL (24 h oxidation) after 2 h of incubation. The protective effect of the phenolic fraction against cell damage caused by oxLDL was noted at 0.1 microg/mL for HUVEC and against tBH at 1000 microg/mL for both HUVEC and hepatocytes. The observed protective effects were probably due to the antioxidant properties of L. caerulea constituents, mainly anthocyanins. Microsome peroxidation and LDL oxidation inhibition results provide promising perspectives into the prevention of some oxidative stress-associated diseases. Other data are important in in vitro systems but seem to be accidental in vivo. PMID:19572653

  14. Cytotoxicity of luteolin in primary rat hepatocytes: the role of CYP3A-mediated ortho-benzoquinone metabolite formation and glutathione depletion.

    PubMed

    Shi, Fuguo; Zhao, Peng; Li, Xiaobing; Pan, Hong; Ma, Shiping; Ding, Li

    2015-11-01

    Luteolin (LUT), an active ingredient in traditional Chinese medicines and an integral part of the human diet, has shown promising pharmacological activities with a great potential for clinical use. The purpose of this study was to evaluate the role of cytochrome P450 (CYP450)-mediated reactive ortho-benzoquinone metabolites formation and glutathione (GSH) depletion in LUT-induced cytotoxicity in primary rat hepatocytes. A reactive ortho-benzoquinone metabolite was identified by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) in rat liver microsomes (RLMs) and rat hepatocytes. Using a specific chemical inhibitor method, the CYP3A subfamily was found to be responsible for the reactive metabolite formation in RLMs. Induction of CYP3A by dexamethasone enhanced LUT-induced cytotoxicity, whereas inhibition of CYP3A by ketoconazole (Keto) decreased the cytotoxicity. The cytotoxicity and cell apoptosis induced by LUT were related to the amount of reactive metabolite formation. Furthermore, Keto inhibited the LUT-induced GSH exhaustion. The cytotoxicity was significantly enhanced by pretreatment with L-buthionine sulfoximine to deplete the intracellular GSH. A time course experiment showed that GSH depletion by LUT was not via oxidation of GSH and occurred prior to the increase in 2', 7'-dichlorofluorescein in hepatocytes. Collectively, these data suggest that CYP3A-mediated reactive metabolite formation plays a critical role in LUT-induced hepatotoxicity, and the direct GSH depletion is an initiating event in LUT-mediated cytotoxicity in primary rat hepatocytes. PMID:25612170

  15. Urokinase and type I plasminogen activator inhibitor production by normal human hepatocytes: modulation by inflammatory agents.

    PubMed

    Busso, N; Nicodeme, E; Chesne, C; Guillouzo, A; Belin, D; Hyafil, F

    1994-07-01

    We examined the effects of inflammatory cytokines (interleukin-1 beta, tumor necrosis factor-alpha and transforming growth factor-beta) on the plasminogen activator system (urokinase, tissue-type plasminogen activator, type 1 plasminogen activator inhibitor) in primary cultures of human hepatocytes. We show that interleukin-1 beta and tumor necrosis factor-alpha increase urokinase-type plasminogen activator production, reinforcing the concept that increased urokinase production is associated with inflammatory processes. By contrast, the same agents (i.e., interleukin-1 beta and tumor necrosis factor-alpha) do not stimulate plasminogen activator inhibitor type 1 production. This latter observation rules out hepatocytes as a major cellular source of plasmatic plasminogen activator inhibitor type 1 during acute-phase-related responses. Among the inflammatory agents used, transforming growth factor-beta was found to be the most effective modulator of both urokinase-type plasminogen activator and plasminogen activator inhibitor type 1, inducing severalfold increases of activity of urokinase-type plasminogen activator, antigen and the corresponding mRNA and increasing plasminogen activator inhibitor type 1 antigen and mRNA levels. Urokinase-type plasminogen activator and plasminogen activator inhibitor type 1 modulation by transforming growth factor-beta may play a critical role in hepatic pathophysiology. PMID:8020888

  16. Docosahexaenoic Acid Ameliorates Fructose-Induced Hepatic Steatosis Involving ER Stress Response in Primary Mouse Hepatocytes

    PubMed Central

    Zheng, Jinying; Peng, Chuan; Ai, Yanbiao; Wang, Heng; Xiao, Xiaoqiu; Li, Jibin

    2016-01-01

    The increase in fructose consumption is considered to be a risk factor for developing nonalcoholic fatty liver disease (NAFLD). We investigated the effects of docosahexaenoic acid (DHA) on hepatic lipid metabolism in fructose-treated primary mouse hepatocytes, and the changes of Endoplasmic reticulum (ER) stress pathways in response to DHA treatment. The hepatocytes were treated with fructose, DHA, fructose plus DHA, tunicamycin (TM) or fructose plus 4-phenylbutyric acid (PBA) for 24 h. Intracellular triglyceride (TG) accumulation was assessed by Oil Red O staining. The mRNA expression levels and protein levels related to lipid metabolism and ER stress response were determined by real-time PCR and Western blot. Fructose treatment led to obvious TG accumulation in primary hepatocytes through increasing expression of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC), two key enzymes in hepatic de novo lipogenesis. DHA ameliorates fructose-induced TG accumulation by upregulating the expression of carnitine palmitoyltransferase 1A (CPT-1α) and acyl-CoA oxidase 1 (ACOX1). DHA treatment or pretreatment with the ER stress inhibitor PBA significantly decreased TG accumulation and reduced the expression of glucose-regulated protein 78 (GRP78), total inositol-requiring kinase 1 (IRE1α) and p-IRE1α. The present results suggest that DHA protects against high fructose-induced hepatocellular lipid accumulation. The current findings also suggest that alleviating the ER stress response seems to play a role in the prevention of fructose-induced hepatic steatosis by DHA. PMID:26805874

  17. Copper Nanoparticles and Copper Sulphate Induced Cytotoxicity in Hepatocyte Primary Cultures of Epinephelus coioides

    PubMed Central

    Wang, Tao; Chen, Xiaoyan; Long, Xiaohua; Liu, Zhaopu; Yan, Shaohua

    2016-01-01

    Copper nanoparticles (Cu-NPs) were widely used in various industrial and commercial applications. The aim of this study was to analyze the cytotoxicity of Cu-NPs on primary hepatocytes of E.coioides compared with copper sulphate (CuSO4). Cultured cells were exposed to 0 or 2.4 mg Cu L-1 as CuSO4or Cu-NPs for 24-h. Results showed either form of Cu caused a dramatic loss in cell viability, more so in the CuSO4 than Cu-NPs treatment. Compared to control, either CuSO4 or Cu-NPs significantly increased reactive oxygen species(ROS) and malondialdehyde(MDA) concentration in hepatocytes by overwhelming total superoxide dismutase (T-SOD) activity, catalase(CAT) activity and glutathione(GSH) concentration. In addition, the antioxidative-related genes [SOD (Cu/Zn), SOD (Mn), CAT, GPx4] were also down-regulated. The apoptosis and necrosis percentage was significantly higher after the CuSO4 or Cu-NPs treatment than the control. The apoptosis was induced by the increased cytochrome c concentration in the cytosol and elevated caspase-3, caspase-8 and caspase-9 activities. Additionally, the apoptosis-related genes (p53, p38β and TNF-α) and protein (p53 protein) were up-regulated after the CuSO4 or Cu-NPs treatment, with CuSO4 exposure having a greater effect than Cu-NPs. In conclusion, Cu-NPs had similar types of toxic effects as CuSO4 on primary hepatocytes of E.coioides, but toxicity of CuSO4 was more severe than that of Cu-NPs. PMID:26890000

  18. Copper Nanoparticles and Copper Sulphate Induced Cytotoxicity in Hepatocyte Primary Cultures of Epinephelus coioides.

    PubMed

    Wang, Tao; Chen, Xiaoyan; Long, Xiaohua; Liu, Zhaopu; Yan, Shaohua

    2016-01-01

    Copper nanoparticles (Cu-NPs) were widely used in various industrial and commercial applications. The aim of this study was to analyze the cytotoxicity of Cu-NPs on primary hepatocytes of E.coioides compared with copper sulphate (CuSO4). Cultured cells were exposed to 0 or 2.4 mg Cu L-1 as CuSO4or Cu-NPs for 24-h. Results showed either form of Cu caused a dramatic loss in cell viability, more so in the CuSO4 than Cu-NPs treatment. Compared to control, either CuSO4 or Cu-NPs significantly increased reactive oxygen species(ROS) and malondialdehyde(MDA) concentration in hepatocytes by overwhelming total superoxide dismutase (T-SOD) activity, catalase(CAT) activity and glutathione(GSH) concentration. In addition, the antioxidative-related genes [SOD (Cu/Zn), SOD (Mn), CAT, GPx4] were also down-regulated. The apoptosis and necrosis percentage was significantly higher after the CuSO4 or Cu-NPs treatment than the control. The apoptosis was induced by the increased cytochrome c concentration in the cytosol and elevated caspase-3, caspase-8 and caspase-9 activities. Additionally, the apoptosis-related genes (p53, p38β and TNF-α) and protein (p53 protein) were up-regulated after the CuSO4 or Cu-NPs treatment, with CuSO4 exposure having a greater effect than Cu-NPs. In conclusion, Cu-NPs had similar types of toxic effects as CuSO4 on primary hepatocytes of E.coioides, but toxicity of CuSO4 was more severe than that of Cu-NPs. PMID:26890000

  19. Expression of human. alpha. sub 1 -antitrypsin in dogs after autologous transplantation of retroviral transduced hepatocytes

    SciTech Connect

    Kay, M.A.; Baley, P.; Rothenberg, S.; Leland, F; Fleming, L.; Ponder, K.P.; Liu, Tajen; Finegold, M.; Darlington, G.; Pokorny, W.; Woo, S.L.C. )

    1992-01-01

    The liver represents an excellent organ for gene therapy since many genetic disorders result from the deficiency of liver-specific gene products. The authors have previously demonstrated that transgenic mouse hepatocytes can be heterologously transplanted into congenic recipients where they survived indefinitely and continued to function as hepatocytes. Here they demonstrate the autologous transplantation of retrovirally transduced canine hepatocytes. In two animals they have transplanted hepatocytes transduced with a retroviral vector containing the human {alpha}{sub 1}-antitrypsin cDNA under transcriptional control of the cytomegalovirus promotor. Both animals had significant human {alpha}{sub 1}-antitrypsin in the serum for 1 month. The results suggest that gene therapy of hepatic deficiencies may be achieved by hepatocellular transplantation after genetic reconstruction with the use of promoters of cellular genes that are active in the normal liver.

  20. In vitro drug metabolism of green tea catechins in human, monkey, dog, rat and mouse hepatocytes.

    PubMed

    Chen, Wendy W; Qin, Geng-Yao; Zhang, Ting; Feng, Wan-Yong

    2012-06-01

    The metabolic fate of green tea catechins [(-)-epicatechin ((-)-EC), (-)-epicatechin-3-gallate (ECG) (-)- epigallocatechin (EGC) and (-)-epigallocatechin-3-gallate (EGCG)] in cryopreserved human, monkey, dog, rat and mouse hepatocytes was studied. Methylation, glucuronidation, sulfation and isomerization pathways of (-)-EC in all five species were found. Methylation, glucuronidation, sulfation, hydrolysis, isomerization and glucosidation pathways of ECG were found. Species differences in metabolism of (-)-EC or ECG were observed. Surprisingly, no metabolites of EGC or EGCG were detected, but chemical oxidation and polymerization were observed under these experimental conditions. It appeared that enzymatic reactions and chemical reactions were differentiated by an additional hydroxyl group on the B-ring between (-)-EC/ECG and EGC/EGCG. For (-)-EC, thirty-five metabolites including isomerized (M6. M10 and M25), glucuronidated (M3, M5 and M11), sulfated (M7, M15, M16, M18, M20, M23, M26), methylated (M2, M9, M12, M17, M19, M21, M27, M30, M32), glucuronated/methylated (M4, M8, M13, M14), sulfated/methylated (M22, M24, M28, M29, M31, M33, M34, M35) and diglucuronidate (M1), were detected and characterized. M11, M18, M19 and M23 were major metabolites in human hepatocytes; M11, M26 and M31 were major metabolites in monkey hepatocytes; M10, M20, M22, M26 and M31 were major metabolites in dog hepatocytes; M5, M6 and M10 were major metabolites in rat hepatocytes; and M5, M6 and M13 were major metabolites in mouse hepatocytes. For ECG, twelve metabolites including isomerized (M1), hydrolyzed (M3), glucosidated (M2), glucuronidated (M4 and M6), sulfated (M9, M11 and M12), methylated (M7), sulfated/glucuronidated/methylated (M8 and M10) and diglucuronidated (M5), were detected and characterized. M4, M11 and M12 were major metabolites in human hepatocytes; M11 and M12 were major metabolites in monkey hepatocytes; M3 and M11 were major metabolites in dog hepatocytes; M4, M6 and

  1. N-Nitrosodiethylamine genotoxicity in primary rat hepatocytes: effects of cytochrome P450 induction by phenobarbital.

    PubMed

    Aiub, Claudia A F; Gadermaier, Gabriele; Oliveira, Izaura; Felzenszwalb, Israel; Ferreira, Fátima; Ribeiro Pinto, Luis Felipe; Eckl, Peter

    2011-10-10

    Primary hepatocytes are widely used in investigating drug metabolism and its toxicological effects. N-Nitrosodiethylamine (NDEA)-induced genotoxicity and cytotoxicity was used in primary cultures of female rat hepatocytes in the presence of phenobarbital (PB). PB pre-treatment (1mM) increased the number of necrotic (2-fold) and apoptotic cells (4-fold) after NDEA treatment (0.21-105 μg/mL). The mitotic indices and the number of micronucleated cells decreased, thus suggesting cytotoxicity. An increased number of chromosomal aberrations were observed after pre-treatment with PB. NDEA-treatment (0.21-21 μg/mL) induced expression of the CYP2B1 and CYP2B2 mRNA and PB treatment alone induced ~6-fold and ~2-fold increases of CYP2B1 and CYP2B2 mRNA, respectively. NDEA treatment following PB exposure increased CYP2B1 mRNA expression under all tested concentrations and also increased CYP2B2 expression at 21 and 105 μg/mL. Our data suggest that the alteration of CYP2B1/2 expression by PB increased the cytotoxicity and genotoxicity of NDEA leading to the final genotoxic metabolite. PMID:21763762

  2. Gene expression analysis of the hepatotoxicant methapyrilene in primary rat hepatocytes: an interlaboratory study.

    PubMed

    Beekman, Johanna M; Boess, Franziska; Hildebrand, Heinrich; Kalkuhl, Arno; Suter, Laura

    2006-01-01

    Genomics technologies are used in several disciplines, including toxicology. However, these technologies are relatively new, and their applications require further investigations. When investigators apply these technologies to in vitro experiments, two major issues need to be clarified: a) can in vitro toxicity studies, in combination with genomics analyses, be used to predict the toxicity of a compound; and b) are the generated toxicogenomics data reproducible between laboratories? These questions were addressed by an interlaboratory study with laboratories of four pharmaceutical companies. We evaluated gene expression patterns from cultured rat primary hepatocytes after a 24-hr incubation with methapyrilene (MP). Extensive data analysis showed that comparison of genomics data from different sources is complex because both experimental and statistical variability are important confounding factors. However, appropriate statistical tools allowed us to use gene expression profiles to distinguish high-dose-treated cells from vehicle-treated cells. Moreover, we correctly identified MP in an independently generated in vitro database, underlining that in vitro toxicogenomics could be a predictive tool for toxicity. From a mechanistic point of view, despite the observed site-to-site variability, there was good concordance regarding the affected biologic processes. Several subsets of regulated genes were obtained by analyzing the data sets with one method or using different statistical analysis methods. The identified genes are involved in cellular processes that are associated to the exposure of primary hepatocytes to MP. Whether they are specific for MP and are cause or consequence of the toxicity requires further investigations. PMID:16393664

  3. Beta-carotene breakdown products enhance genotoxic effects of oxidative stress in primary rat hepatocytes.

    PubMed

    Alija, A J; Bresgen, N; Sommerburg, O; Langhans, C D; Siems, W; Eckl, P M

    2006-06-01

    Since it has to be expected that individuals exposed to oxidative stress who take supplements of beta-carotene are simultaneously exposed to both beta-carotene cleavage products (CPs) and oxidative stress, and both exposures have been demonstrated to cause genotoxic effects in primary rat hepatocytes, cyto- and genotoxic effects on primary rat hepatocytes after supplementation of the medium with increasing concentrations of a CP mixture during exposure to oxidative stress by treatment with either DMNQ (2,3-dimethoxy-1,4-naphthoquinone) or hypoxia/reoxygenation (Hy/Reox) was investigated. The cytological endpoints analysed were the mitotic indices, the percentages of apoptotic and necrotic cells, the percentages of micronucleated (MN) cells and the number of chromosomal aberrations (CAs) and sister chromatid exchanges (SCE). The results obtained clearly demonstrate that the CP mixture enhances the genotoxic effects of oxidative stress exposure, whereas it had no effect at all on the endpoints of cytotoxicity studied. These results further support the hypothesis that CP might be responsible for the reported carcinogenic response in the beta-CArotene and Retinol Efficacy Trial (CARET) and Alpha-Tocopherol Beta-carotene Cancer prevention (ATBC) chemoprevention trials. PMID:16418177

  4. Cost-effective differentiation of hepatocyte-like cells from human pluripotent stem cells using small molecules.

    PubMed

    Tasnim, Farah; Phan, Derek; Toh, Yi-Chin; Yu, Hanry

    2015-11-01

    Significant efforts have been invested into the differentiation of stem cells into functional hepatocyte-like cells that can be used for cell therapy, disease modeling and drug screening. Most of these efforts have been concentrated on the use of growth factors to recapitulate developmental signals under in vitro conditions. Using small molecules instead of growth factors would provide an attractive alternative since small molecules are cell-permeable and cheaper than growth factors. We have developed a protocol for the differentiation of human embryonic stem cells into hepatocyte-like cells using a predominantly small molecule-based approach (SM-Hep). This 3 step differentiation strategy involves the use of optimized concentrations of LY294002 and bromo-indirubin-3'-oxime (BIO) for the generation of definitive endoderm; sodium butyrate and dimethyl sulfoxide (DMSO) for the generation of hepatoblasts and SB431542 for differentiation into hepatocyte-like cells. Activin A is the only growth factor required in this protocol. Our results showed that SM-Hep were morphologically and functionally similar or better compared to the hepatocytes derived from the growth-factor induced differentiation (GF-Hep) in terms of expression of hepatic markers, urea and albumin production and cytochrome P450 (CYP1A2 and CYP3A4) activities. Cell viability assays following treatment with paradigm hepatotoxicants Acetaminophen, Chlorpromazine, Diclofenac, Digoxin, Quinidine and Troglitazone showed that their sensitivity to these drugs was similar to human primary hepatocytes (PHHs). Using SM-Hep would result in 67% and 81% cost reduction compared to GF-Hep and PHHs respectively. Therefore, SM-Hep can serve as a robust and cost effective replacement for PHHs for drug screening and development. PMID:26310107

  5. Troglitazone, but not rosiglitazone, damages mitochondrial DNA and induces mitochondrial dysfunction and cell death in human hepatocytes

    SciTech Connect

    Rachek, Lyudmila I.; Yuzefovych, Larysa V.; LeDoux, Susan P.; Julie, Neil L.; Wilson, Glenn L.

    2009-11-01

    Thiazolidinediones (TZDs), such as troglitazone (TRO) and rosiglitazone (ROSI), improve insulin resistance by acting as ligands for the nuclear receptor peroxisome proliferator-activated receptor-gamma (PPARgamma). TRO was withdrawn from the market because of reports of serious hepatotoxicity. A growing body of evidence suggests that TRO caused mitochondrial dysfunction and induction of apoptosis in human hepatocytes but its mechanisms of action remain unclear. We hypothesized that damage to mitochondrial DNA (mtDNA) is an initiating event involved in TRO-induced mitochondrial dysfunction and hepatotoxicity. Primary human hepatocytes were exposed to TRO and ROSI. The results obtained revealed that TRO, but not ROSI at equimolar concentrations, caused a substantial increase in mtDNA damage and decreased ATP production and cellular viability. The reactive oxygen species (ROS) scavenger, N-acetyl cystein (NAC), significantly diminished the TRO-induced cytotoxicity, suggesting involvement of ROS in TRO-induced hepatocyte cytotoxicity. The PPARgamma antagonist (GW9662) did not block the TRO-induced decrease in cell viability, indicating that the TRO-induced hepatotoxicity is PPARgamma-independent. Furthermore, TRO induced hepatocyte apoptosis, caspase-3 cleavage and cytochrome c release. Targeting of a DNA repair protein to mitochondria by protein transduction using a fusion protein containing the DNA repair enzyme Endonuclease III (EndoIII) from Escherichia coli, a mitochondrial translocation sequence (MTS) and the protein transduction domain (PTD) from HIV-1 TAT protein protected hepatocytes against TRO-induced toxicity. Overall, our results indicate that significant mtDNA damage caused by TRO is a prime initiator of the hepatoxicity caused by this drug.

  6. Preincubation of rat and human hepatocytes with cytoprotectants prior to cryopreservation can improve viability and function upon thawing.

    PubMed

    Terry, Claire; Dhawan, Anil; Mitry, Ragai R; Lehec, Sharon C; Hughes, Robin D

    2005-12-01

    Cryopreservation of human hepatocytes is important for the treatment of liver disease by hepatocyte transplantation and also for the use of hepatocytes as an in vitro model of the liver. One factor in the success of cryopreservation is the quality of cells before freezing. Preincubation of hepatocytes with cytoprotective compounds to allow recovery from the isolation process prior to cryopreservation, such as those that will boost cellular adenosine triphosphate (ATP) content or antioxidants, may improve the viability and function of cells upon thawing. Rat hepatocytes were used to investigate the effects of preincubation with 10 compounds: precursors (glucose, fructose, glutathione, and S-adenosyl-L-methionine), antioxidants (ascorbic acid and alpha-lipoic acid), and compounds with multiple effects (N-acetylcysteine, pentoxifylline, prostaglandin E(1), and tauroursodeoxycholic acid). Human hepatocytes were then used to investigate 5 of the original 10 compounds (glucose, fructose, alpha-lipoic acid, S-adenosyl-L-methionine, and pentoxifylline). Glucose preincubation (100-300 mM) improved the viability and attachment efficiency of rat hepatocytes and improved the viability and reduced lactate dehydrogenase (LDH) leakage of human hepatocytes. Fructose preincubation (100-300 mM) improved the viability and attachment efficiency of rat hepatocytes and improved the attachment efficiency of human hepatocytes. alpha-lipoic acid preincubation (0.5-5 mM) improved the viability and attachment efficiency of both rat and human hepatocytes. At a concentration of 2.5 mM alpha-lipoic acid also improved the albumin production of human hepatocytes. In conclusion, preincubation of hepatocytes prior to cryopreservation can improve the viability and function of thawed cells and may provide a method of obtaining better-quality cryopreserved hepatocytes for transplantation. PMID:16315306

  7. Characterization of the liver-macrophages isolated from a mixed primary culture of neonatal swine hepatocytes.

    PubMed

    Kitani, Hiroshi; Yoshioka, Miyako; Takenouchi, Takato; Sato, Mitsuru; Yamanaka, Noriko

    2014-01-01

    We recently developed a novel procedure to obtain liver-macrophages in sufficient number and purity using a mixed primary culture of rat and bovine hepatocytes. In this study, we aim to apply this method to the neonatal swine liver. Swine parenchymal hepatocytes were isolated by a two-step collagenase perfusion method and cultured in T75 culture flasks. Similar to the rat and bovine cells, the swine hepatocytes retained an epithelial cell morphology for only a few days and progressively changed into fibroblastic cells. After 5-13 days of culture, macrophage-like cells actively proliferated on the mixed fibroblastic cell sheet. Gentle shaking of the culture flask followed by the transfer and brief incubation of the culture supernatant resulted in a quick and selective adhesion of macrophage-like cells to a plastic dish surface. After rinsing dishes with saline, the attached macrophage-like cells were collected at a yield of 10(6) cells per T75 culture flask at 2-3 day intervals for more than 3 weeks. The isolated cells displayed a typical macrophage morphology and were strongly positive for macrophage markers, such as CD172a, Iba-1 and KT022, but negative for cytokeratin, desmin and α-smooth muscle actin, indicating a highly purified macrophage population. The isolated cells exhibited phagocytosis of polystyrene microbeads and a release of inflammatory cytokines upon lipopolysaccharide stimulation. This shaking and attachment method is applicable to the swine liver and provides a sufficient number of macrophages without any need of complex laboratory equipments. PMID:24707456

  8. Low-shear modelled microgravity environment maintains morphology and differentiated functionality of primary porcine hepatocyte cultures.

    PubMed

    Nelson, Leonard J; Walker, Simon W; Hayes, Peter C; Plevris, John N

    2010-01-01

    Hepatocytes cultured in conventional static culture rapidly lose polarity and differentiated function. This could be explained by gravity-induced sedimentation, which prevents formation of complete three-dimensional (3D) cell-cell/cell-matrix interactions and disrupts integrin-mediated signals (including the most abundant hepatic integrin alpha(5)beta(1)), important for cellular polarity and differentiation. Cell culture in a low fluid shear modelled microgravity (about 10(-2) g) environment promotes spatial colocation/self-aggregation of dissociated cells and induction of 3D differentiated liver morphology. Previously, we demonstrated the utility of a NASA rotary bioreactor in maintaining key metabolic functions and 3D aggregate formation of high-density primary porcine hepatocyte cultures over 21 days. Using serum-free chemically defined medium, without confounding interactions of exogenous bioscaffolding or bioenhancing surface materials, we investigated features of hepatic cellular polarity and differentiated functionality, including expression of hepatic integrin alpha(5), as markers of functional morphology. We report here that in the absence of exogenous biomatrix scaffolding, hepatocytes cultured in serum-free chemically defined medium in a microgravity environment rapidly (<24 h) form macroscopic (2-5 mm), compacted 3D hepatospheroid structures consisting of a shell of glycogen-positive viable cells circumscribing a core of eosinophilic cells. The spheroid shell layers exhibited ultrastructural, morphological and functional features of differentiated, polarized hepatic tissue including strong expression of the integrin alpha(5) subunit, functional bile canaliculi, albumin synthesis, and fine ultrastructure reminiscent of in vivo hepatic tissue. The low fluid shear microgravity environment may promote tissue-like self-organization of dissociated cells, and offer advantages over spheroids cultured in conventional formats to delineate optimal conditions for

  9. Functional activity of human hepatocytes under traumatic disease.

    PubMed

    Kudryavtseva, M V; Stein, G I; Shashkov, B V; Kudryavtsev, B N

    1998-03-01

    Absorption and fluorescent cytophotometry techniques were applied to studies of RNA as well as of total glycogen and its fractions as the parameters of functional activity of the hepatocytes in patients with severe mechanical trauma, both with and without autointoxication (AI). Slides were stained with gallocyanine-chromalums to determine the RNA content and were processed by the fluorescent PAS-reaction for the glycogen content. To trace the dynamics of RNA and glycogen contents in the liver punction biopsies were done in the same patients. A quick increase in the RNA content took place in both groups of patients at the first period (within the first 3 days) of traumatic disease. At the second period of disease the hepatocyte RNA content in patients without AI was found to decrease up to the initial level whereas that in patients with AI increased on the average by 36% of the initial values. The total glycogen content in hepatocytes of all the patients changed insignificantly in the course of disease but its labile fraction in patients with AI decreased to 70% of the total. The increase of hepatocyte synthetic activity and the maintenance of the high glycogen level are indicative of the large compensatory potential of the liver that enables it to carry an intensive functional load under AI conditions. PMID:9570502

  10. Hepatocyte nuclear factor-4alpha and bile acids regulate human concentrative nucleoside transporter-1 gene expression.

    PubMed

    Klein, Kerstin; Kullak-Ublick, Gerd A; Wagner, Martin; Trauner, Michael; Eloranta, Jyrki J

    2009-04-01

    The concentrative nucleoside transporter-1 (CNT1) is a member of the solute carrier 28 (SLC28) gene family and is expressed in the liver, intestine, and kidneys. CNT1 mediates the uptake of naturally occurring pyrimidine nucleosides, but also nucleoside analogs used in anticancer and antiviral therapy. Thus expression levels of CNT1 may affect the pharmacokinetics of these drugs and the outcome of drug therapy. Because little is known about the transcriptional regulation of human CNT1 gene expression, we have characterized the CNT1 promoter with respect to DNA response elements and their binding factors. The transcriptional start site of the CNT1 gene was determined by 5'-RACE. In silico analysis revealed the existence of three putative binding sites for the nuclear receptor hepatocyte nuclear factor-4alpha (HNF-4alpha) within the CNT1 promoter. A luciferase reporter gene construct containing the CNT1 promoter region was transactivated by HNF-4alpha in human cell lines derived from the liver, intestine, and kidneys. Consistent with this, we showed in electromobility shift assays that HNF-4alpha specifically binds to two conserved direct repeat-1 motifs within the proximal CNT1 promoter. In cotransfection experiments, the transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1alpha further increased, whereas the bile acid-inducible corepressor small heterodimer partner reduced, HNF-4alpha-dependent CNT1 promoter activity. Consistent with the latter phenomenon, CNT1 mRNA expression levels were suppressed in primary human hepatocytes upon bile acid treatment. Supporting the physiological relevance and species conservation of this effect, ileal Cnt1 mRNA expression was decreased upon bile acid feeding and increased upon bile duct ligation in mice. PMID:19228884

  11. Effects of macroporous hydroxyapatite carriers on the growth and function of human hepatoblasts derived from fetal hepatocytes.

    PubMed

    Ishii, Takaaki; Saito, Hiroshi; Komizu, Yuji; Tomoshige, Ryuichi; Matsushita, Taku

    2016-08-01

    Improvement of three-dimensional (3D) culture conditions, including substrates for cell growth, is needed for various cell-based applications. In this study, we developed hydroxyapatite (HAp) macroporous carriers having several pore size distributions and tried to obtain the findings about the effective pore sizes for the growth and function of hepatoblasts derived from human fetal hepatocytes. Cellular CYP3A4 activity was significantly enhanced when 20% HAp macroporous carrier was used, reaching 1.49±0.28 pmol/10(6) cells/min of benzyloxyresorufin-O-dealkylation activity, which is comparable to that of primary human hepatocytes from livers of adult donors. Analysis of the pore size (the radius of curvature) distribution of each HAp carrier using a 3D-electron beam surface roughness analyzer revealed two peaks of pore size distribution at 30-40 μm and 70-80 μm, respectively. Thirty-five percent of the pores in the 20% carrier had a size distribution within 50-80 μm. Especially, pores of 70-80 μm were more abundant in the 20% HAp carrier than in the 10% and 30% HAp carriers. These results suggested that a HAp carrier with the pore size distribution of 50-80 μm might be effective for cell growth and function in human hepatoblasts derived from fetal hepatocytes. PMID:26968126

  12. Human Hepatocytes and Hematolymphoid Dual Reconstitution in Treosulfan-Conditioned uPA-NOG Mice

    PubMed Central

    Gutti, Tanuja L.; Knibbe, Jaclyn S.; Makarov, Edward; Zhang, Jinjin; Yannam, Govardhana R.; Gorantla, Santhi; Sun, Yimin; Mercer, David F.; Suemizu, Hiroshi; Wisecarver, James L.; Osna, Natalia A.; Bronich, Tatiana K.; Poluektova, Larisa Y.

    2015-01-01

    Human-specific HIV-1 and hepatitis co-infections significantly affect patient management and call for new therapeutic options. Small xenotransplantation models with human hepatocytes and hematolymphoid tissue should facilitate antiviral/antiretroviral drug trials. However, experience with mouse strains tested for dual reconstitution is limited, with technical difficulties such as risky manipulations with newborns and high mortality rates due to metabolic abnormalities. The best animal strains for hepatocyte transplantation are not optimal for human hematopoietic stem cell (HSC) engraftment, and vice versa. We evaluated a new strain of highly immunodeficient nonobese diabetic/Shi-scid (severe combined immunodeficiency)/IL-2Rγcnull (NOG) mice that carry two copies of the mouse albumin promoter-driven urokinase-type plasminogen activator transgene for dual reconstitution with human liver and immune cells. Three approaches for dual reconstitution were evaluated: i) freshly isolated fetal hepatoblasts were injected intrasplenically, followed by transplantation of cryopreserved HSCs obtained from the same tissue samples 1 month later after treosulfan conditioning; ii) treosulfan conditioning is followed by intrasplenic simultaneous transplantation of fetal hepatoblasts and HSCs; and iii) transplantation of mature hepatocytes is followed by mismatched HSCs. The long-term dual reconstitution was achieved on urokinase-type plasminogen activator–NOG mice with mature hepatocytes (not fetal hepatoblasts) and HSCs. Even major histocompatibility complex mismatched transplantation was sustained without any evidence of hepatocyte rejection by the human immune system. PMID:24200850

  13. Endogenous bile acid disposition in rat and human sandwich-cultured hepatocytes

    SciTech Connect

    Marion, Tracy L.; Perry, Cassandra H.; St Claire, Robert L.; Brouwer, Kim L.R.

    2012-05-15

    Sandwich-cultured hepatocytes (SCH) are used commonly to investigate hepatic transport protein-mediated uptake and biliary excretion of substrates. However, little is known about the disposition of endogenous bile acids (BAs) in SCH. In this study, four endogenous conjugated BAs common to rats and humans [taurocholic acid (TCA), glycocholic acid (GCA), taurochenodeoxycholic acid (TCDCA), and glycochenodeoxycholic acid (GCDCA)], as well as two BA species specific to rodents (α- and β-tauromuricholic acid; α/β TMCA), were profiled in primary rat and human SCH. Using B-CLEAR{sup ®} technology, BAs were measured in cells + bile canaliculi, cells, and medium of SCH by LC-MS/MS. Results indicated that, just as in vivo, taurine-conjugated BA species were predominant in rat SCH, while glycine-conjugated BAs were predominant in human SCH. Total intracellular BAs remained relatively constant over days in culture in rat SCH. Total BAs in control (CTL) cells + bile, cells, and medium were approximately 3.4, 2.9, and 8.3-fold greater in human than in rat. The estimated intracellular concentrations of the measured total BAs were 64.3 ± 5.9 μM in CTL rat and 183 ± 56 μM in CTL human SCH, while medium concentrations of the total BAs measured were 1.16 ± 0.21 μM in CTL rat SCH and 9.61 ± 6.36 μM in CTL human SCH. Treatment of cells for 24 h with 10 μM troglitazone (TRO), an inhibitor of the bile salt export pump (BSEP) and the Na{sup +}-taurocholate cotransporting polypeptide (NTCP), had no significant effect on endogenous BAs measured at the end of the 24-h culture period, potentially due to compensatory mechanisms that maintain BA homeostasis. These data demonstrate that BAs in SCH are similar to in vivo, and that SCH may be a useful in vitro model to study alterations in BA disposition if species differences are taken into account. -- Highlights: ► Bile acids (BAs) were measured in rat and human sandwich-cultured hepatocytes (SCH). ► Cell and medium BA

  14. A novel matrix for the short-term storage of cells: utility in drug metabolism and drug transporter studies with rat, dog and human hepatocytes.

    PubMed

    Palmgren, Anna-Pia; Fihn, Britt-Marie; Bird, James; Courtney, Paul; Grime, Ken

    2013-06-01

    1. The SureTran matrix is a novel method facilitating short-term maintenance of fresh primary hepatocyte cellular function and offers the potential use of primary cells "as fresh" for several days post isolation. In the study presented, the maintenance of several key phase I and II drug metabolizing enzyme and drug transporter activities is demonstrated with rat and dog hepatocytes preserved for up to 7 days after cell isolation. 2. Intrinsic clearance values were determined for 60 new chemical entities using rat hepatocytes freshly isolated at AstraZeneca and rat hepatocytes prepared at the facilities of Abcellute Ltd (SureTran purveyors), stored and incubated 24 hours after isolation. A very good correspondence in the intrinsic clearance values underlines the utility of the cell maintenance matrix. 3. For human hepatocytes many of the enzyme activities assayed were well maintained for 7 days of storage but some declined to below 50% of initial values between day 4 and 7 of storage. Human OATP1B1 activity was only determined with one batch and declined to 51% of the initial test value by day 4 and further down to 35% by day 7. PMID:23137276

  15. Metabolism of methyleugenol in liver microsomes and primary hepatocytes: pattern of metabolites, cytotoxicity, and DNA-adduct formation.

    PubMed

    Cartus, Alexander T; Herrmann, Kristin; Weishaupt, Lucas W; Merz, Karl-Heinz; Engst, Wolfram; Glatt, Hansruedi; Schrenk, Dieter

    2012-09-01

    Methyleugenol (1) is a constituent of many foods, in particular of herbal spices, and is used as flavoring agent in foodstuffs and as fragrance in cosmetics. 1 has been found to be carcinogenic in rodents, its metabolite, 1-hydroxymethyleugenol (2) acting as proximate DNA-binding carcinogen. We incubated 1 with liver microsomes of rat, bovine, and human origin. We found 2, 3-hydroxymethylisoeugenol (3), and 6-hydroxymethyleugenol (4) as major metabolites, and 1-oxomethyleugenol (5), 3-oxomethylisoeugenol (6), eugenol (9), chavibetol (11), and (RS)-2,3-dihydroxy-2,3-dihydromethyleugenol (7) as minor metabolites. Methyleugenol-2,3-epoxide (8), probably the precursor of 7, could not be detected. Incubations with synthetic metabolites were applied in order to uncover metabolic pathways. Incubations with primary rat hepatocytes revealed mainly nonconjugated 2 and conjugated 4, and minor amounts of partly conjugated 7 and conjugated 9 + 11. The "reactive metabolites" 3, 5, 6, and 8 were not detectable, possibly due to rapid reaction with cellular macromolecules. The highest cytotoxicity (resazurin reduction assay and lactate dehydrogenase leakage assay) was observed for the main metabolite 2 and its secondary metabolite 5 with EC(50) values of 50 and 10 µM, respectively. Deoxyadenosine or deoxyguanosine adducts were formed by incubating 1 or metabolites with rat hepatocytes. The rank order of adduct formation was 2 > 1 > 3 > 6, whereas 4, 5, and 8 were inactive. In conclusion, we present a virtually complete pattern of microsomal (rat, bovine, and human) and hepatocellular (rat) metabolites of 1 suggesting the formation of several reactive metabolites possibly involved in carcinogenicity, organ toxicity, and immune reactions. PMID:22610610

  16. Quantitative expression profile of hepatobiliary transporters in sandwich cultured rat and human hepatocytes.

    PubMed

    Li, Na; Bi, Yi-An; Duignan, David B; Lai, Yurong

    2009-01-01

    As sandwich cultured (SC) hepatocytes can repolarize to form bile canalicular networks, allowing active excretion of compounds in a vectorial manner, the model has been widely used for assessing the transporter related complexity of ADME/tox issues. A lack of quantitative information on transporter expression during cell culture has made in vitro to in vivo extrapolation of hepatobiliary transport difficult. In the present study, using our newly developed LC-MS/MS absolute quantitative methods, we determined the quantitative expression profile of three biliary transporters in SC rat and human hepatocytes. A significant shift of hepatobiliary transporter proteins was observed both in human and rat sandwich cultures. A decrease of BSEP/Bsep protein and an increase of BCRP/Bcrp protein were detected in both rat and human hepatocytes over time in culture. Interestingly, Mrp2 in rat hepatocytes was significantly diminished, while MRP2 constantly increased in human hepatocytes during the cell culture. Consequently, the interspecies difference between rat and human in absolute amount of MRP2/Mrp2 was minimized over time in culture. Following the sandwich culture, the species difference of hepatobiliary transporter protein between human and rat at day 5 post SC was diminished (MRP2/Mrp2), identical (BSEP/Bsep) or reversed (BCRP/Bcrp), compared to the in vivo situation. In addition, the absolute protein amount of BCRP/Bcrp or MRP2/Mrp2 was proportionally correlated with the intrinsic biliary clearance estimated in various lots of SC rat and human hepatocytes. The results revealed that absolute protein amount is a key determinant for hepatobiliary clearance and could provide fundamental support on extrapolation of biliary secretion from in vitro to in vivo. PMID:19545175

  17. In vitro metabolism and toxicity assessment of N-methylcarbazole in primary cultured rat hepatocytes.

    PubMed

    Yang, W; Jiang, T R; Davis, P J; Acosta, D

    1991-01-01

    N-Methycarbazole (NMC), a carcinogen and mutagen in tobacco smoke, was converted to two major metabolites by primary cultured rat hepatocytes as measured by high performance liquid chromatography (HPLC): N-hydroxymethylcarbazole (NHMC) and carbazole. These two metabolites had comparable retention times and identical ultraviolet spectra as those of reference standards. Identical retention times and mass spectra were also observed as detected by gas chromatography-mass spectroscopy (GC-MS) for NHMC and its reference standard. The toxicities of NMC and its two metabolites were assessed by lactate dehydrogenase (LDH) leakage and neutral red (NR) uptake. The rank order of cytotoxicity of NMC and its metabolites was found to be: NHMC greater than NMC greater than carbazole. Thus, we conclude that the hydroxylation of NMC to NHMC may represent a toxification step, while the further dealkylation to carbazole is most likely a detoxication process. PMID:1896996

  18. SIRT1 Disruption in Human Fetal Hepatocytes Leads to Increased Accumulation of Glucose and Lipids

    PubMed Central

    Tobita, Takamasa; Guzman-Lepe, Jorge; Takeishi, Kazuki; Nakao, Toshimasa; Wang, Yang; Meng, Fanying; Deng, Chu-Xia; Collin de l’Hortet, Alexandra; Soto-Gutierrez, Alejandro

    2016-01-01

    There are unprecedented epidemics of obesity, such as type II diabetes and non-alcoholic fatty liver diseases (NAFLD) in developed countries. A concerning percentage of American children are being affected by obesity and NAFLD. Studies have suggested that the maternal environment in utero might play a role in the development of these diseases later in life. In this study, we documented that inhibiting SIRT1 signaling in human fetal hepatocytes rapidly led to an increase in intracellular glucose and lipids levels. More importantly, both de novo lipogenesis and gluconeogenesis related genes were upregulated upon SIRT1 inhibition. The AKT/FOXO1 pathway, a major negative regulator of gluconeogenesis, was decreased in the human fetal hepatocytes inhibited for SIRT1, consistent with the higher level of gluconeogenesis. These results indicate that SIRT1 is an important regulator of lipid and carbohydrate metabolisms within human fetal hepatocytes, acting as an adaptive transcriptional response to environmental changes. PMID:26890260

  19. SIRT1 Disruption in Human Fetal Hepatocytes Leads to Increased Accumulation of Glucose and Lipids.

    PubMed

    Tobita, Takamasa; Guzman-Lepe, Jorge; Takeishi, Kazuki; Nakao, Toshimasa; Wang, Yang; Meng, Fanying; Deng, Chu-Xia; Collin de l'Hortet, Alexandra; Soto-Gutierrez, Alejandro

    2016-01-01

    There are unprecedented epidemics of obesity, such as type II diabetes and non-alcoholic fatty liver diseases (NAFLD) in developed countries. A concerning percentage of American children are being affected by obesity and NAFLD. Studies have suggested that the maternal environment in utero might play a role in the development of these diseases later in life. In this study, we documented that inhibiting SIRT1 signaling in human fetal hepatocytes rapidly led to an increase in intracellular glucose and lipids levels. More importantly, both de novo lipogenesis and gluconeogenesis related genes were upregulated upon SIRT1 inhibition. The AKT/FOXO1 pathway, a major negative regulator of gluconeogenesis, was decreased in the human fetal hepatocytes inhibited for SIRT1, consistent with the higher level of gluconeogenesis. These results indicate that SIRT1 is an important regulator of lipid and carbohydrate metabolisms within human fetal hepatocytes, acting as an adaptive transcriptional response to environmental changes. PMID:26890260

  20. Application of a Micropatterned Cocultured Hepatocyte System To Predict Preclinical and Human-Specific Drug Metabolism.

    PubMed

    Ballard, T Eric; Wang, Shuai; Cox, Loretta M; Moen, Mark A; Krzyzewski, Stacy; Ukairo, Okechukwu; Obach, R Scott

    2016-02-01

    Laboratory animal models are the industry standard for preclinical risk assessment of drug candidates. Thus, it is important that these species possess profiles of drug metabolites that are similar to those anticipated in human, since metabolites also could be responsible for biologic activities or unanticipated toxicity. Under most circumstances, preclinical species reflect human in vivo metabolites well; however, there have been several notable exceptions, and understanding and predicting these exceptions with an in vitro system would be very useful. Human micropatterned cocultured (MPCC) hepatocytes have been shown to recapitulate human in vivo qualitative metabolic profiles, but the same demonstration has not been performed yet for laboratory animal species. In this study, we investigated several compounds that are known to produce human-unique metabolites through CYP2C9, UGT1A4, aldehyde oxidase (AO), or N-acetyltransferase that were poorly covered or not detected at all in the selected preclinical species. To perform our investigation we used 24-well MPCC hepatocyte plates having three individual human donors and a single donor each of monkey, dog, and rat to study drug metabolism at four time points per species. Through the use of the multispecies MPCC hepatocyte system, the metabolite profiles of the selected compounds in human donors effectively captured the qualitative in vivo metabolite profile with respect to the human metabolite of interest. Human-unique metabolites that were not detected in vivo in certain preclinical species (normally dog and rat) were also not generated in the corresponding species in vitro, confirming that the MPCC hepatocytes can provide an assessment of preclinical species metabolism. From these results, we conclude that multispecies MPCC hepatocyte plates could be used as an effective in vitro tool for preclinical understanding of species metabolism relative to humans and aid in the choice of appropriate preclinical models. PMID

  1. Metabolism of benzo[a]pyrene by cultured human hepatocytes from multiple donors.

    PubMed

    Moore, C J; Gould, M N

    1984-12-01

    Primary hepatocyte cultures from six human donors were established and their abilities to metabolize the polycyclic aromatic hydrocarbon carcinogen benzo[a]pyrene (B[a]P) were examined. Cells from each donor were plated at similar densities (1 X 10(7) cells/100 mm dish). All cultures metabolized B[a]P to a significant extent (24-35 nmol in 24 h) and h.p.l.c. profiles of the organic solvent-soluble and glucuronidated B[a]P metabolites were obtained for all donors. The predominant extracellular organic solvent-soluble B[a]P metabolites were the 9,10- and 7,8-dihydrodiols, 9-hydroxy-B[a]P, and a mixture of tetrols, but the general ratios of these metabolites varied widely among the cells from different donors. In contrast, profiles were highly reproducible in cells from the same donor treated with B[a]P at either 8 or 24 h after initial plating. There was less variability in the amounts of specific B[a]P metabolites conjugated to glucuronic acid by cells from various donors. This variability could not be correlated with cell viability or overall levels of B[a]P metabolism. In addition, B[a]P metabolism by fresh and cryopreserved hepatocytes from the same donor was compared. While there was only a small reduction in the level of total B[a]P metabolism after cell freezing, there was a 3- to 5-fold increase in production of B[a]P-7,8-dihydrodiol, found both in the extracellular medium and as glucuronic acid conjugates, by the cryopreserved cells tested. PMID:6499110

  2. Enhancement of hepatocyte differentiation from human embryonic stem cells by Chinese medicine Fuzhenghuayu

    PubMed Central

    Chen, Jiamei; Gao, Wei; Zhou, Ping; Ma, Xiaocui; Tschudy-Seney, Benjamin; Liu, Chenghai; Zern, Mark A; Liu, Ping; Duan, Yuyou

    2016-01-01

    Chinese medicine, Fuzhenghuayu (FZHY), appears to prevent fibrosis progression and improve liver function in humans. Here we found that FZHY enhanced hepatocyte differentiation from human embryonic stem cells (hESC). After treatment with FZHY, albumin expression was consistently increased during differentiation and maturation process, and expression of metabolizing enzymes and transporter were also increased. Importantly, expression of mesenchymal cell and cholangiocyte marker was significantly reduced by treatment with FZHY, indicating that one possible mechanism of FZHY’s role is to inhibit the formation of mesenchymal cells and cholangiocytes. Edu-labelled flow cytometric analysis showed that the percentage of the Edu positive cells was increased in the treated cells. These results indicate that the enhanced proliferation involved hepatocytes rather than another cell type. Our investigations further revealed that these enhancements by FZHY are mediated through activation of canonical Wnt and ERK pathways and inhibition of Notch pathway. Thus, FZHY not only promoted hepatocyte differentiation and maturation, but also enhanced hepatocyte proliferation. These results demonstrate that FZHY appears to represent an excellent therapeutic agent for the treatment of liver fibrosis, and that FZHY treatment can enhance our efforts to generate mature hepatocytes with proliferative capacity for cell-based therapeutics and for pharmacological and toxicological studies. PMID:26733102

  3. High Content Analysis of Human Pluripotent Stem Cell Derived Hepatocytes Reveals Drug Induced Steatosis and Phospholipidosis

    PubMed Central

    Pradip, Arvind; Steel, Daniella; Jacobsson, Susanna; Holmgren, Gustav; Ingelman-Sundberg, Magnus; Sartipy, Peter; Björquist, Petter; Johansson, Inger; Edsbagge, Josefina

    2016-01-01

    Hepatotoxicity is one of the most cited reasons for withdrawal of approved drugs from the market. The use of nonclinically relevant in vitro and in vivo testing systems contributes to the high attrition rates. Recent advances in differentiating human induced pluripotent stem cells (hiPSCs) into pure cultures of hepatocyte-like cells expressing functional drug metabolizing enzymes open up possibilities for novel, more relevant human cell based toxicity models. The present study aimed to investigate the use of hiPSC derived hepatocytes for conducting mechanistic toxicity testing by image based high content analysis (HCA). The hiPSC derived hepatocytes were exposed to drugs known to cause hepatotoxicity through steatosis and phospholipidosis, measuring several endpoints representing different mechanisms involved in drug induced hepatotoxicity. The hiPSC derived hepatocytes were benchmarked to the HepG2 cell line and generated robust HCA data with low imprecision between plates and batches. The different parameters measured were detected at subcytotoxic concentrations and the order of which the compounds were categorized (as severe, moderate, mild, or nontoxic) based on the degree of injury at isomolar concentration corresponded to previously published data. Taken together, the present study shows how hiPSC derived hepatocytes can be used as a platform for screening drug induced hepatotoxicity by HCA. PMID:26880940

  4. Transcriptional Regulation of CYP2B6 Expression by Hepatocyte Nuclear Factor 3β in Human Liver Cells

    PubMed Central

    Li, Linhao; Li, Daochuan; Heyward, Scott; Wang, Hongbing

    2016-01-01

    CYP2B6 plays an increasingly important role in xenobiotic metabolism and detoxification. The constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) have been established as predominant regulators for the inductive expression of CYP2B6 gene in human liver. However, there are dramatic interindividual variabilities in CYP2B6 expression that cannot be fully explained by the CAR/PXR-based modulation alone. Here, we show that expression level of CYP2B6 was correlated with that of hepatocyte nuclear factor 3β (HNF3β) in human primary hepatocytes prepared from 35 liver donors. Utilizing recombinant virus-mediated overexpression or knockdown of HNF3β in HepG2 cells, as well as constructs containing serial deletion and site-directed mutation of HNF3β binding motifs in CYP2B6 luciferase reporter assays, we demonstrated that the presence or lack of HNF3β expression markedly correlated with CYP2B6 gene expression and its promoter activity. Novel enhancer modules of HNF3β located upstream of the CYP2B6 gene transcription start site were identified and functionally validated as key elements governing HNF3β-mediated CYP2B6 expression. Chromatin immunoprecipitation assays in human primary hepatocytes and surface plasmon resonance binding affinity experiments confirmed the essential role of these enhancers in the recruitment of HNF3β to the promoter of CYP2B6 gene. Overall, these findings indicate that HNF3β represents a new liver enriched transcription factor that is involved in the transcription of CYP2B6 gene and contributes to the large interindividual variations of CYP2B6 expression in human population. PMID:26930610

  5. Environmental pollutants parathion, paraquat and bisphenol A show distinct effects towards nuclear receptors-mediated induction of xenobiotics-metabolizing cytochromes P450 in human hepatocytes.

    PubMed

    Vrzal, Radim; Zenata, Ondrej; Doricakova, Aneta; Dvorak, Zdenek

    2015-10-01

    Environmental pollutants parathion, bisphenol A and paraquat were not systematically studied towards the effects on the expression of phase I xenobiotics-metabolizing cytochromes P450 (CYPs). We monitored their effects on the expression of selected CYPs in primary cultures of human hepatocytes. Moreover, we investigated their effects on the receptors regulating these CYPs, particularly arylhydrocarbon receptor (AhR), pregnane X receptor (PXR) and glucocorticoid receptor (GR) by gene reporter assays. We found that parathion and bisphenol A are the activators of AhR. Moreover, they are the inducers of CYP1A1 mRNA in hepatoma cells HepG2 as well as in human hepatocytes by AhR-dependent mechanism via formation of AhR-DNA-binding complex, as revealed by gel shift assay. All three compounds possessed anti-glucocorticoid action as revealed by GR-dependent gene reporter assay and a decline in tyrosine aminotransferase (TAT) gene expression in human hepatocytes. Moreover, parathion and bisphenol A are the activators of PXR and inducers of CYP3A4 mRNA and protein in the primary cultures of human hepatocytes. In conclusion, the studied compounds displayed distinct activities towards nuclear receptors involved in many biological processes and these findings may help us to better understand their adverse actions in pathological states followed after their exposure. PMID:26196221

  6. Effects of nutritional and hormonal factors on the metabolism of retinol-binding protein by primary cultures of rat hepatocytes

    SciTech Connect

    Dixon, J.L.; Goodman, D.S.

    1987-01-01

    Studies were conducted to explore hormonal and nutritional factors that might be involved in the regulation of retinol-binding protein (RBP) synthesis and secretion by the liver. The studies employed primary cultures of hepatocytes from normal rats. When cells were cultured in Dulbecco's modified Eagle's medium alone, a high rate of RBP secretion was observed initially, which declined and became quite low by 24 hr. Supplementing the medium with amino acids maintained RBP and albumin secretion at moderate (but less than initial) rates for at least 3 days. Further addition of dexamethasone maintained the production and secretion rates of RBP, transthyretin, and albumin close to the initial rates for up to 3-5 days in culture as measured by radioimmunoassay. Hormonally treated hepatocytes produced and secreted RBP, transthyretin, and albumin at both absolute and relative rates similar to physiological values, as estimated from rates reported by others from studies in vivo and with perfused livers. Glucagon addition partially maintained the secretion rates of these 3 proteins, but less effectively than did dexamethasone. A number of other hormones, added singly or in combination, did not affect RBP production or secretion. Addition of retinol to the cultured normal hepatocytes was without effect upon RBP secretion. These studies show that supplementing the culture medium of hepatocytes with amino acids and dexamethasone maintains RBP production and secretion for several days. In normal hepatocytes, with ample supply of retinol available within the cell, addition of exogenous retinol does not appear to influence RBP metabolism or secretion by the cells.

  7. Aneuploidy is permissive for hepatocyte-like cell differentiation from human induced pluripotent stem cells

    PubMed Central

    2014-01-01

    Background The characterization of induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs) routinely includes analyses of chromosomal integrity. The belief is that pluripotent stem cells best suited to the generation of differentiated derivatives should display a euploid karyotype; although, this does not appear to have been formally tested. While aneuploidy is commonly associated with cell transformation, several types of somatic cells, including hepatocytes, are frequently aneuploid and variation in chromosomal content does not contribute to a transformed phenotype. This insight has led to the proposal that dynamic changes in the chromosomal environment may be important to establish genetic diversity within the hepatocyte population and such diversity may facilitate an adaptive response by the liver to various insults. Such a positive contribution of aneuploidy to liver function raises the possibility that, in contrast to existing dogma, aneuploid iPSCs may be capable of generating hepatocyte-like cells that display hepatic activities. Results We examined whether a human iPSC line that had multiple chromosomal aberrations was competent to differentiate into hepatocytes and found that loss of normal chromosomal content had little impact on the production of hepatocyte-like cells from iPSCs. Conclusions iPSCs that harbor an abnormal chromosomal content retain the capacity to generate hepatocyte–like cells with high efficiency. PMID:25002137

  8. APPARENT SEXUAL DIFFERENCES IN METABOLISM OF INORGANIC ARSENIC IN HUMAN HEPATOCYTES

    EPA Science Inventory

    APPARENT SEXUAL DIFFERENCES IN METABOLISM OF INORGANIC ARSENIC IN HUMAN HEPATOCYTES. M Styblo1, G A Hamilton1, E L LeCluyse1 and D J Thomas2. 1University of North Carolina, Chapel Hill, NC, USA; 2US EPA, ORD, NHEERL, Research Triangle Park, NC, USA.
    The liver is considered a m...

  9. Under the skin: Biotransformation of para-aminophenol and para-phenylenediamine in reconstructed human epidermis and human hepatocytes.

    PubMed

    Nohynek, Gerhard J; Duche, Daniel; Garrigues, Alexia; Meunier, Pierre-Alain; Toutain, Herve; Leclaire, Jacques

    2005-09-15

    We investigated the biotransformation of the oxidative arylamine (AA) hair dye ingredients [14C]-para-aminophenol (PAP) and [14C]-para-phenylenediamine (PPD) in reconstructed human epidermis and human hepatocytes. Human epidermis quantitatively transformed PAP to its N-acetylated derivative (APAP), whereas hepatocytes transformed PAP to sulfate or glucuronic acid conjugates of APAP or PAP as well as free APAP. Epidermis and hepatocytes converted PPD to N-mono- (MAPPD) and N,N'-di-acetylated (DAPPD) derivatives. At higher concentrations of PPD (250-1000 microM), epidermis or hepatocytes produced more of the MAPPD, whereas concentrations below 250 microM and lower favoured formation of the DAPPD metabolite. When compared with epidermis, human hepatocytes had a three-fold or eight-fold greater capacity for generation of MAPPD or DAPPD, respectively. No evidence of transformation of PAP or PPD to N-hydroxylated derivatives was found in epidermis or hepatocytes. Our results suggest that (i) after dermal absorption of PAP or PPD, humans are systemically exposed to acetylated derivatives; (ii) current in vitro skin absorption studies may be inadapated for determination of human systemic exposure to AAs due to reduced or absent metabolic capacity of non-viable skin; (iii) due to qualitative differences between dermal and hepatic metabolism, oral toxicity studies may be unsuited for the hazard assessment of dermal exposure to AAs; and (iv) use of induced rodent liver S9 metabolic activation systems for in vitro genotoxicity studies may produce misleading results on the hazard of human dermal exposure to AAs. In conclusion, our data support the growing evidence that AAs are transformed in human skin and suggest that current practices of safety assessment of AAs should take these findings into account. PMID:15890478

  10. Inhibition of glycogenolysis in primary rat hepatocytes by 1, 4-dideoxy-1,4-imino-D-arabinitol.

    PubMed Central

    Andersen, B; Rassov, A; Westergaard, N; Lundgren, K

    1999-01-01

    1,4-Dideoxy-1,4-imino-d-arabinitol (DAB) was identified previously as a potent inhibitor of both the phosphorylated and non-phosphorylated forms of glycogen phosphorylase (EC 2.4.1.1). In the present study, the effects of DAB were investigated in primary cultured rat hepatocytes. The transport of DAB into hepatocytes was dependent on time and DAB concentration. The rate of DAB transport was 192 pmol/min per mg of protein per mM DAB(medium-concentration). In hepatocytes, DAB inhibited basal and glucagon-stimulated glycogenolysis with IC(50) values of 1.0+/-0.3 and 1.1+/-0.2 microM, respectively. The primary inhibitory effect of DAB on glycogenolysis was shown to be due to inhibition of glycogen phosphorylase but, at higher concentrations of DAB, inhibition of the debranching enzyme (4-alpha-glucanotransferase, EC 2.4.1.25) may have an effect. No effects on glycogen synthesis were observed, demonstrating that glycogen recycling does not occur in cultured hepatocytes under the conditions tested. Furthermore, DAB had no effects on phosphorylase kinase, the enzyme responsible for phosphorylation and thereby activation of glycogen phosphorylase, or on protein phosphatase 1, the enzyme responsible for inactivation of glycogen phosphorylase through dephosphorylation. PMID:10477265

  11. Cytotoxic and genotoxic effects of beta-carotene breakdown products on primary rat hepatocytes.

    PubMed

    Alija, A J; Bresgen, N; Sommerburg, O; Siems, W; Eckl, P M

    2004-05-01

    According to Siems and colleagues, free radical attack on beta-carotene results in the formation of high amounts of cleavage products with prooxidant activities towards subcellular organelles such as mitochondria. This finding may be an explanation for the contradictory results obtained with beta-carotene in clinical efficacy and cancer prevention trials. Since primary hepatocytes proved to be very sensitive indicators of the genotoxic action of suspect mutagens/carcinogens we therefore investigated a beta-carotene cleavage products mixture (CP), apo8'- carotenal (apo8') and beta-carotene utilizing primary cultures of rat hepatocytes. The end-points tested were: the mitotic index, the percentage of necrotic and apoptotic cells, micronucleated cells, chromosomal aberrations and sister chromatid exchanges (SCE). Our results indicate a genotoxic potential of both CP and apo8' already at the concentrations 100 nM and 1 microM, i.e. at pathophysiologically relevant levels of beta-carotene and beta-carotene breakdown products. A 3 h treatment with CP induced statistically significant levels of micronuclei at concentrations of 0.1, 1 and 10 microM and chromosomal aberrations at concentrations of 1, 5 and 10 microM. Apo8' induced statistically significant levels of micronuclei at concentrations of 0.1, 1 and 5 microM and chromosomal aberrations at concentrations of 0.1, 1 and 10 microM. Statistically significant increases in SCE induction were only observed at a concentration of 10 microM CP and apo8'. In contrast, no significant cytotoxic effects of these substances were observed. Since beta-carotene induced neither significant cytotoxic nor genotoxic effects at concentrations ranging from 0.01 up to 10 microM, these observations indicate that most likely beta-carotene breakdown products are responsible for the occurrence of carcinogenic effects found in the Alpha-Tocopherol Beta-Carotene Cancer Prevention (ATBC) Study and the Beta-CArotene and RETinol Efficacy Trial

  12. In Vitro Metabolism of 3,4-Methylenedioxymethamphetamine in Human Hepatocytes

    PubMed Central

    Ramaley, Corinne; Leonard, Susan C.; Miller, Jeffrey D.; Wilson, Denita Takesha-Mashia; Chang, Sai Y.; Chen, Qingyu; Li, Feng; Du, Chengan

    2014-01-01

    Users of the illicit drug, 3,4-methylenedioxymethamphetamine (MDMA), show signs of neurotoxicity. However, the precise mechanism of neurotoxicity caused by use of MDMA has not yet been elucidated. Synthetic glutathione (GSH) conjugates of MDMA are transported into the brain by the GSH transporter and subsequently produce neurotoxicity. The objective of this research is to show direct evidence of the formation of GSH adducts of MDMA in human hepatocytes. High-performance liquid chromatography coupled with tandem mass spectrometry was utilized to examine in vitro incubations of MDMA with cryopreserved human hepatocytes. The use of hydrophilic liquid chromatography in combination with linear ion trap mass spectrometry permitted the identification of two possible GSH metabolites. Enhanced product ion scans of m/z = 499 and 487 amu of extracts from hepatocytes treated with 1.0 mM MDMA show a distinct fragmentation pattern (m/z 194.2, 163, 135, 105), suggesting the formation of MDMA–GSH conjugate, MDMA-SG and 3,4-dihydroxymethamphetamine-SG. The formation of an MDMA–GSH conjugate was further supported by the apparent lack of the same fragmentation pattern from hepatocyte samples without MDMA treatment. The results generated from this study yield valuable qualitative and quantitative information about the neurotoxic thioether metabolites formed from MDMA in humans. PMID:24682111

  13. A Human Hepatocyte-Bearing Mouse: An Animal Model to Predict Drug Metabolism and Effectiveness in Humans

    PubMed Central

    Yoshizato, Katsutoshi; Tateno, Chise

    2009-01-01

    Preclinical studies to predict the efficacy and safety of drugs have conventionally been conducted almost exclusively in mice and rats as rodents, despite the differences in drug metabolism between humans and rodents. Furthermore, human (h) viruses such as hepatitis viruses do not infect the rodent liver. A mouse bearing a liver in which the hepatocytes have been largely repopulated with h-hepatocytes would overcome some of these disadvantages. We have established a practical, efficient, and large-scale production system for such mice. Accumulated evidence has demonstrated that these hepatocyte-humanized mice are a useful and reliable animal model, exhibiting h-type responses in a series of in vivo drug processing (adsorption, distribution, metabolism, excretion) experiments and in the infection and propagation of hepatic viruses. In this review, we present the current status of studies on chimeric mice and describe their usefulness in the study of peroxisome proliferator-activated receptors. PMID:19884982

  14. Automated detection of hepatotoxic compounds in human hepatocytes using HepaRG cells and image-based analysis of mitochondrial dysfunction with JC-1 dye

    SciTech Connect

    Pernelle, K.; Le Guevel, R.; Glaise, D.; Stasio, C. Gaucher-Di; Le Charpentier, T.; Bouaita, B.; Corlu, A.; Guguen-Guillouzo, C.

    2011-08-01

    In this study, our goal was to develop an efficient in situ test adapted to screen hepatotoxicity of various chemicals, a process which remains challenging during the early phase of drug development. The test was based on functional human hepatocytes using the HepaRG cell line, and automation of quantitative fluorescence microscopy coupled with automated imaging analysis. Differentiated HepaRG cells express most of the specific liver functions at levels close to those found in primary human hepatocytes, including detoxifying enzymes and drug transporters. A triparametric analysis was first used to evaluate hepatocyte purity and differentiation status, mainly detoxication capacity of cells before toxicity testing. We demonstrated that culturing HepaRG cells at high density maintained high hepatocyte purity and differentiation level. Moreover, evidence was found that isolating hepatocytes from 2-week-old confluent cultures limited variations associated with an ageing process occurring over time in confluent cells. Then, we designed a toxicity test based on detection of early mitochondrial depolarisation associated with permeability transition (MPT) pore opening, using JC-1 as a metachromatic fluorescent dye. Maximal dye dimerization that would have been strongly hampered by efficient efflux due to the active, multidrug-resistant (MDR) pump was overcome by coupling JC-1 with the MDR inhibitor verapamil. Specificity of this test was demonstrated and its usefulness appeared directly dependent on conditions supporting hepatic cell competence. This new hepatotoxicity test adapted to automated, image-based detection should be useful to evaluate the early MPT event common to cell apoptosis and necrosis and simultaneously to detect involvement of the multidrug resistant pump with target drugs in a human hepatocyte environment. - Highlights: > We define conditions to preserve differentiation of selective pure HepaRG hepatocyte cultures. > In these conditions, CYPs

  15. Expression of human factor IX in rabbit hepatocytes by retrovirus-mediated gene transfer: Potential for gene therapy of hemophilia B

    SciTech Connect

    Thompson, A.R. Puget Sound Blood Center, Seattle, WA ); Darlington, G. ); Armentano, D.; Woo, S.L.C.

    1990-08-01

    Hemophilia B (Christmas disease) is a chromosome X-linked blood clotting disorder which results when factor IX is deficient or functionally defective. The enzyme is synthesized in the liver, and the existence of animal models for this genetic disease will permit the development of somatic gene therapy protocols aimed at transfer of the functional gene into the liver. The authors report the construction of an N2-based recombinant retroviral vector, NCMVFIX, for efficient transfer and expression of human factor IX cDNA in primary rabbit hepatocytes. In this construct the human cytomegalovirus immediate early promoter directs the expression of factor IX. Hepatocytes were isolated from 3-week-old New Zealand White rabbits, infected with the recombinant virus, and analyzed for secretion of active factor IX. The infected rabbit hepatocytes produced human factor IX that is indistinguishable from enzyme derived from normal human plasma. The recombinant protein is sufficiently {gamma}-carboxylated and is functionally active in clotting assays. These results establish the feasibility of using infected hepatocytes for the expression of this protein and are a step toward the goal of correcting hemophilia B by hepatic gene transfer.

  16. Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells

    NASA Astrophysics Data System (ADS)

    Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

    2016-08-01

    Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases.

  17. Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells.

    PubMed

    Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

    2016-08-01

    Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases. PMID:27379400

  18. Cell-sized condensed collagen microparticles for preparing microengineered composite spheroids of primary hepatocytes.

    PubMed

    Yamada, Masumi; Hori, Ayaka; Sugaya, Sari; Yajima, Yuya; Utoh, Rie; Yamato, Masayuki; Seki, Minoru

    2015-10-01

    The reconstitution of extracellular matrix (ECM) components in three-dimensional (3D) cell culture environments with microscale precision is a challenging issue. ECM microparticles would potentially be useful as solid particulate scaffolds that can be incorporated into 3D cellular constructs, but technologies for transforming ECM proteins into cell-sized stable particles are currently lacking. Here, we describe new processes to produce highly condensed collagen microparticles by means of droplet microfluidics or membrane emulsification. Droplets of an aqueous solution of type I collagen were formed in a continuous phase of polar organic solvent followed by rapid dissolution of water molecules into the continuous phase because the droplets were in a non-equilibrium state. We obtained highly unique, disc-shaped condensed collagen microparticles with a final collagen concentration above 10% and examined factors affecting particle size and morphology. After testing the cell-adhesion properties on the collagen microparticles, composite multicellular spheroids comprising the particles and primary rat hepatocytes were formed using microfabricated hydrogel chambers. We found that the ratio of the cells and particles is critical in terms of improvement of hepatic functions in the composite spheroids. The presented methodology for incorporating particulate-form ECM components in multicellular spheroids would be advantageous because of the biochemical similarity with the microenvironments in vivo. PMID:26308935

  19. Furin is the primary in vivo convertase of angiopoietin-like 3 and endothelial lipase in hepatocytes.

    PubMed

    Essalmani, Rachid; Susan-Resiga, Delia; Chamberland, Ann; Asselin, Marie-Claude; Canuel, Maryssa; Constam, Daniel; Creemers, John W; Day, Robert; Gauthier, Dany; Prat, Annik; Seidah, Nabil G

    2013-09-13

    The proprotein convertases (PCs) furin, PC5/6, and PACE4 exhibit unique and/or complementary functions. Their knock-out (KO) in mice resulted in strong and specific phenotypes demonstrating that, in vivo, these PCs are unique and essential during development. However, they also exhibit redundant functions. Liver angiopoietin-like 3 (ANGPTL3) inhibits lipolysis by binding to lipoprotein lipases. It is found in the plasma as full length and truncated forms. The latter is more active and generated by cleavage at a furin-like site. Endothelial lipase (EL) binds heparin sulfate proteoglycans on cell surfaces and catalyzes the hydrolysis of HDL phospholipids. EL activity is regulated by two endogenous inhibitors, ANGPTL3 and ANGPTL4, and by PCs that inactivate EL through cleavage releasing the N-terminal catalytic and C-terminal lipid-binding domains. Herein, because furin and PC5/6 complete KOs are lethal, we used mice lacking furin or PC5/6 specifically in hepatocytes (hKO) or mice completely lacking PACE4. In primary hepatocytes, ANGPTL3 was processed into a shorter form of ANGPTL3 intracellularly by furin only, and extracellularly mainly by PACE4. In vivo, the absence of furin in hepatocytes reduced by ∼50% the circulating levels of cleaved ANGPTL3, while the lack of PACE4 had only a minor effect. Analysis of the EL processing in primary hepatocytes and in vivo revealed that it is mostly cleaved by furin. However, the lack of furin or PC5/6 in hepatocytes and complete PACE4 KO did not appreciably modify plasma HDL levels or EL activity. Thus, inhibition of furin in liver would not be expected to modify the plasma lipid profiles. PMID:23918928

  20. Activation-dependent mitochondrial translocation of Foxp3 in human hepatocytes.

    PubMed

    Rojas, Joselyn; Teran-Angel, Guillermo; Barbosa, Luisa; Peterson, Darrell L; Berrueta, Lisbeth; Salmen, Siham

    2016-05-01

    Foxp3 is considered to be the master regulator for the development and function of regulatory T cells (Treg). Recently Foxp3, has been detected in extra lymphoid tissue, and in hepatocytes and has been associated with hepatocellular carcinoma (HCC), although its role has not been defined. Since it is expected that there is a relationship between protein localization, activity and cellular function, the aim of this study was to explore the subcellular localization of Foxp3 in resting and stimulated human hepatocytes. Foxp3 expression was measured by flow cytometry, subcellular fractioning, and immunofluorescence, and this data was used to track the shuttling of Foxp3 in different subcellular compartments in hepatocytes (HepG2 cell line), stimulated by using the PKC activators (PMA), core and preS1/2 antigen from hepatitis B virus (HBV). Our data shows that besides the nuclear location, mitochondrial translocation was detected after stimulation with PMA and at to a lesser extent, with preS1/2. In addition, Foxp3 is localizes at outer mitochondrial membrane. These results suggest a non-canonical role of Foxp3 in the mitochondrial compartment in human hepatocytes, and opens a new field about their role in liver damages during HBV infection. PMID:27068374

  1. Tandem overexpression of five human factors renders murine hepatocytes susceptible to hepatitis C virus.

    PubMed

    Lv, L; Kang, Q; Yu, X; Gao, B; Hu, T; Ma, P; Zhang, Y; Yan, F; Xiao, J; Deng, J; Zhou, X; Xu, J

    2015-03-01

    Development of mouse model of hepatitis C virus (HCV) infection has great significance in drug screening and vaccine research. The barriers of interspecies transmission of HCV are increasingly better understood. Human factors, namely low-density lipoprotein receptor (hLDLR), CD81 (hCD81), scavenger receptor class B type I (hSCARB1), occludin (hOCLN) and claudin 1 (hCLDN1) are all required for rendering mouse hepatocytes permissive to HCV. With the aim to humanize mouse hepatocytes we constructed two recombinant vectors tandemly expressing the first three and the last two HCV entry factors mentioned above, respectively. Cotransfection of mouse hepatocytes with these vectors made them permissive to HCV binding and entry. Tandem overexpression of hLDLR, hSCARB1, hCD81, hCLDN1 and hOCLN is a novel approach to tailoring mouse hepatocytes to HCV binding and entry which can be further used to establish a mouse model of HCV infection as a basis for developing antiviral drugs and vaccines. PMID:25790047

  2. 3D cultured immortalized human hepatocytes useful to develop drugs for blood-borne HCV

    SciTech Connect

    Aly, Hussein Hassan; Shimotohno, Kunitada; Hijikata, Makoto

    2009-02-06

    Due to the high polymorphism of natural hepatitis C virus (HCV) variants, existing recombinant HCV replication models have failed to be effective in developing effective anti-HCV agents. In the current study, we describe an in vitro system that supports the infection and replication of natural HCV from patient blood using an immortalized primary human hepatocyte cell line cultured in a three-dimensional (3D) culture system. Comparison of the gene expression profile of cells cultured in the 3D system to those cultured in the existing 2D system demonstrated an up-regulation of several genes activated by peroxisome proliferator-activated receptor alpha (PPAR{alpha}) signaling. Furthermore, using PPAR{alpha} agonists and antagonists, we also analyzed the effect of PPAR{alpha} signaling on the modulation of HCV replication using this system. The 3D in vitro system described in this study provides significant insight into the search for novel anti-HCV strategies that are specific to various strains of HCV.

  3. Nuclear lactate dehydrogenase modulates histone modification in human hepatocytes

    SciTech Connect

    Castonguay, Zachary; Auger, Christopher; Thomas, Sean C.; Chahma, M’hamed; Appanna, Vasu D.

    2014-11-07

    Highlights: • Nuclear LDH is up-regulated under oxidative stress. • SIRT1 is co-immunoprecipitated bound to nuclear LDH. • Nuclear LDH is involved in histone deacetylation and epigenetics. - Abstract: It is becoming increasingly apparent that the nucleus harbors metabolic enzymes that affect genetic transforming events. Here, we describe a nuclear isoform of lactate dehydrogenase (nLDH) and its ability to orchestrate histone deacetylation by controlling the availability of nicotinamide adenine dinucleotide (NAD{sup +}), a key ingredient of the sirtuin-1 (SIRT1) deacetylase system. There was an increase in the expression of nLDH concomitant with the presence of hydrogen peroxide (H{sub 2}O{sub 2}) in the culture medium. Under oxidative stress, the NAD{sup +} generated by nLDH resulted in the enhanced deacetylation of histones compared to the control hepatocytes despite no discernable change in the levels of SIRT1. There appeared to be an intimate association between nLDH and SIRT1 as these two enzymes co-immunoprecipitated. The ability of nLDH to regulate epigenetic modifications by manipulating NAD{sup +} reveals an intricate link between metabolism and the processing of genetic information.

  4. Purification and characterization of a growth factor from rat platelets for mature parenchymal hepatocytes in primary cultures.

    PubMed Central

    Nakamura, T; Teramoto, H; Ichihara, A

    1986-01-01

    A growth factor (HGF) stimulating DNA synthesis of adult rat hepatocytes in primary culture was found in rat platelets. HGF was purified from rat platelets to homogeneity by a three-step procedure: stimulation of its release from platelets by thrombin, cation-exchanger fast protein liquid chromatography on a Mono S column, and heparin-Sepharose chromatography. HGF was clearly distinguishable from the platelet-derived growth factor (PDGF) by fast protein liquid chromatography. HGF was a heat- and acid-labile cationic protein that was inactivated by reduction with dithiothreitol. Its molecular mass was estimated to be 27 kDa by NaDodSO4/PAGE and its amino acid composition was very different from that of PDGF. The purified HGF stimulated DNA synthesis in adult rat hepatocytes at 2 ng/ml and was maximally effective at 20 ng/ml; its effect was additive or synergistic with those of insulin and EGF, depending on their combinations. HGF did not stimulate DNA synthesis of Swiss 3T3 cells, while PDGF did not stimulate that of hepatocytes. Thus, HGF showed clearly different cell specificity from PDGF in its growth-promoting activities. These findings indicate that HGF is a growth factor in platelets for mature hepatocytes. Images PMID:3529086

  5. Protective Role of Morin, a Flavonoid, against High Glucose Induced Oxidative Stress Mediated Apoptosis in Primary Rat Hepatocytes

    PubMed Central

    Kapoor, Radhika; Kakkar, Poonam

    2012-01-01

    Apoptosis is an early event of liver damage in diabetes and oxidative stress has been linked to accelerate the apoptosis in hepatocytes. Therefore, the compounds that can scavenge ROS may confer regulatory effects on high-glucose induced apoptosis. In the present study, primary rat hepatocytes were exposed to high concentration (40 mM) of glucose. At this concentration decreased cell viability and enhanced ROS generation was observed. Depleted antioxidant status of hepatocytes under high glucose stress was also observed as evident from transcriptional level and activities of antioxidant enzymes. Further, mitochondrial depolarisation was accompanied by the loss of mitochondrial integrity and altered expression of Bax and Bcl-2. Increased translocation of apoptotic proteins like AIF (Apoptosis inducing factor) & Endo-G (endonuclease-G) from its resident place mitochondria to nucleus was also observed. Cyt-c residing in the inter-membrane space of mitochondria also translocated to cytoplasm. These apoptotic proteins initiated caspase activation, DNA fragmentation, chromatin condensation, increased apoptotic DNA content in glucose treated hepatocytes, suggesting mitochondria mediated apoptotic mode of cell death. Morin, a dietary flavonoid from Psidium guajava was effective in increasing the cell viability and decreasing the ROS level. It maintained mitochondrial integrity, inhibited release of apoptotic proteins from mitochondria, prevented DNA fragmentation, chromatin condensation and hypodiploid DNA upon exposure to high glucose. This study confirms the capacity of dietary flavonoid Morin in regulating apoptosis induced by high glucose via mitochondrial mediated pathway through intervention of oxidative stress. PMID:22899998

  6. Prediction of interindividual differences in hepatic functions and drug sensitivity by using human iPS-derived hepatocytes

    PubMed Central

    Takayama, Kazuo; Morisaki, Yuta; Kuno, Shuichi; Nagamoto, Yasuhito; Harada, Kazuo; Furukawa, Norihisa; Ohtaka, Manami; Nishimura, Ken; Imagawa, Kazuo; Sakurai, Fuminori; Tachibana, Masashi; Sumazaki, Ryo; Noguchi, Emiko; Nakanishi, Mahito; Hirata, Kazumasa; Kawabata, Kenji; Mizuguchi, Hiroyuki

    2014-01-01

    Interindividual differences in hepatic metabolism, which are mainly due to genetic polymorphism in its gene, have a large influence on individual drug efficacy and adverse reaction. Hepatocyte-like cells (HLCs) differentiated from human induced pluripotent stem (iPS) cells have the potential to predict interindividual differences in drug metabolism capacity and drug response. However, it remains uncertain whether human iPSC-derived HLCs can reproduce the interindividual difference in hepatic metabolism and drug response. We found that cytochrome P450 (CYP) metabolism capacity and drug responsiveness of the primary human hepatocytes (PHH)-iPS-HLCs were highly correlated with those of PHHs, suggesting that the PHH-iPS-HLCs retained donor-specific CYP metabolism capacity and drug responsiveness. We also demonstrated that the interindividual differences, which are due to the diversity of individual SNPs in the CYP gene, could also be reproduced in PHH-iPS-HLCs. We succeeded in establishing, to our knowledge, the first PHH-iPS-HLC panel that reflects the interindividual differences of hepatic drug-metabolizing capacity and drug responsiveness. PMID:25385620

  7. Long-Term Coculture Strategies for Primary Hepatocytes and Liver Sinusoidal Endothelial Cells

    PubMed Central

    Bale, Shyam Sundhar; Golberg, Inna; Jindal, Rohit; McCarty, William J.; Luitje, Martha; Hegde, Manjunath; Bhushan, Abhinav; Usta, Osman Berk

    2015-01-01

    Hepatocytes and their in vitro models are essential tools for preclinical screening studies for drugs that affect the liver. Most of the current models primarily focus on hepatocytes alone and lack the contribution of non-parenchymal cells (NPCs), which are significant through both molecular and the response of the NPCs themselves. Models that incorporate NPCs alongside hepatocytes hold the power to enable more realistic recapitulation and elucidation of cell interactions and cumulative drug response. Hepatocytes and liver sinusoidal endothelial cells (LSECs) account for ∼80% of the liver mass where the LSECs line the walls of blood vessels, and act as a barrier between hepatocytes and blood. Culturing LSECs with hepatocytes to generate multicellular physiologically relevant in vitro liver models has been a major hurdle since LSECs lose their phenotype rapidly after isolation. To this end, we describe the application of collagen gel (1) in a sandwich and (2) as an intervening extracellular matrix layer to coculture hepatocytes with LSECs for extended periods. These coculture configurations provide environments wherein hepatocyte and LSECs, through cell–cell contacts and/or secretion factors, lead to enhanced function and stability of the cocultures. Our results show that in these configurations, hepatocytes and LSECs maintained their phenotypes when cultured together as a mixture, and showed stable secretion and metabolic activity for up to 4 weeks. Immunostaining for sinusoidal endothelial 1 (SE-1) antibody demonstrated retention of LSEC phenotype during the culture period. In addition, LSECs cultured alone maintained high viability and SE-1 expression when cultured within a collagen sandwich configuration up to 4 weeks. Albumin production of the cocultures was 10–15 times higher when LSECs were cultured as a bottom layer (with an intervening collagen layer) and as a mixture in a sandwich configuration, and native CYP 1A1/2 activity was at least 20 times

  8. Featured Article: Isolation, characterization, and cultivation of human hepatocytes and non-parenchymal liver cells.

    PubMed

    Pfeiffer, Elisa; Kegel, Victoria; Zeilinger, Katrin; Hengstler, Jan G; Nüssler, Andreas K; Seehofer, Daniel; Damm, Georg

    2015-05-01

    Primary human hepatocytes (PHH) are considered to be the gold standard for in vitro testing of xenobiotic metabolism and hepatotoxicity. However, PHH cultivation in 2D mono-cultures leads to dedifferentiation and a loss of function. It is well known that hepatic non-parenchymal cells (NPC), such as Kupffer cells (KC), liver endothelial cells (LEC), and hepatic stellate cells (HSC), play a central role in the maintenance of PHH functions. The aims of the present study were to establish a protocol for the simultaneous isolation of human PHH and NPC from the same tissue specimen and to test their suitability for in vitro co-culture. Human PHH and NPC were isolated from tissue obtained by partial liver resection by a two-step EDTA/collagenase perfusion technique. The obtained cell fractions were purified by Percoll density gradient centrifugation. KC, LEC, and HSC contained in the NPC fraction were separated using specific adherence properties and magnetic activated cell sorting (MACS®). Identified NPC revealed a yield of 1.9 × 10(6) KC, 2.7 × 10(5) LEC and 4.7 × 10(5) HSC per gram liver tissue, showing viabilities >90%. Characterization of these NPC showed that all populations went through an activation process, which influenced the cell fate. The activation of KC strongly depended on the tissue quality and donor anamnesis. KC became activated in culture in association with a loss of viability within 4-5 days. LEC lost specific features during culture, while HSC went through a transformation process into myofibroblasts. The testing of different culture conditions for HSC demonstrated that they can attenuate, but not prevent dedifferentiation in vitro. In conclusion, the method described allows the isolation and separation of PHH and NPC in high quality and quantity from the same donor. PMID:25394621

  9. Use of mRNA expression to detect the induction of drug metabolising enzymes in rat and human hepatocytes

    SciTech Connect

    Richert, L. Tuschl, G.; Pekthong, D.; Mantion, G.; Weber, J.-C.; Mueller, S.O.

    2009-02-15

    It is important to investigate the induction of cytochrome P450 (CYP) enzymes by drugs. The most relevant end point is enzyme activity; however, this requires many cells and is low throughput. We have compared the CYP1A, CYP2B and CYP3A induction response to eight inducers in rat and human hepatocytes using enzyme activities (CYP1A2 (ethoxyresorufin), 2B (benzoxyresorufin for rat and bupropion for human) and CYP3A (testosterone)) and Taqman{sup TM} Low Density Array (TLDA) analysis. There was a good correlation between the induction of CYP1A2, CYP2B6 and CYP3A4 enzyme activities and mRNA expression in human hepatocytes. In contrast, BROD activities and mRNA expression in rat hepatocytes correlated poorly. However, bupropion hydroxylation correlated well with Cyp2b1 expression in rat hepatocytes. TLDA analysis of a panel of mRNAs encoding for CYPs, phase 2 enzymes, nuclear receptors and transporters revealed that the main genes induced by the 8 compounds tested were the CYPs. AhR ligands also induced UDP-glucuronosyltransferases and glutathione S-transferases in rat and human hepatocytes. The transporters, MDR1, MDR3 and OATPA were the only transporter genes significantly up-regulated in human hepatocytes. In rat hepatocytes Bsep, Mdr2, Mrp2, Mrp3 and Oatp2 were up-regulated. We could then show a good in vivo:in vitro correlation in the induction response of isolated rat hepatocytes and ex-vivo hepatic microsomes for the drug development candidate, EMD392949. In conclusion, application of TLDA methodology to investigate the potential of compounds to induce enzymes in rat and human hepatocytes increases the throughput and information gained from one assay, without reducing the predictive capacity.

  10. Evaluation of human hepatocytes cultured by three-dimensional spheroid systems for drug metabolism.

    PubMed

    Ohkura, Takako; Ohta, Kunihiro; Nagao, Takuya; Kusumoto, Kumiko; Koeda, Akiko; Ueda, Tadayoshi; Jomura, Tomoko; Ikeya, Takeshi; Ozeki, Emiko; Wada, Kazuki; Naitoh, Kazushi; Inoue, Yukiko; Takahashi, Naoki; Iwai, Hisakazu; Arakawa, Hiroshi; Ogihara, Takuo

    2014-01-01

    We investigated the utility of three-dimensional (3D) spheroid cultures of human hepatocytes in discovering drug metabolites. Metabolites of acetaminophen, diclofenac, lamotrigine, midazolam, propranolol and salbutamol were analyzed by liquid chromatography-tandem mass spectrometry (LC/MS/MS) to measure enzyme activities in this system cultured for 2 and 7 days. Sequential metabolic reactions by Phase I and then Phase II enzymes were found in diclofenac [CYP2C9 and UDP-glucuronyltransferases (UGTs)], midazolam (CYP3A4 and UGTs) and propranolol (CYP1A2/2D6 and UGTs). Moreover, lamotrigine and salbutamol were metabolized to lamotrigine-N-glucuronide and salbutamol 4-O-sulfate, respectively. These metabolites, which are human specific, could be observed in clinical studies, but not in conventional hepatic culture systems as in previous reports. Acetaminophen was metabolized to glucuronide and sulfate conjugates, and N-acetyl-p-benzo-quinoneimine (NAPQI) and its metabolites were not observed. In addition, mRNA of drug-metabolism enzymes [CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4, UGT1A1, UGT2B7, sulfotransferase 1A1 (SULT1A1) and glutathione S-transferase pi 1 (GSTP1)], which were measured by qRT-PCR, were expressed in the human hepatocyte spheroids. In conclusion, these results suggest that human hepatocyte spheroids are useful in discovering drug metabolites. PMID:24695277

  11. Small-Molecule-Driven Hepatocyte Differentiation of Human Pluripotent Stem Cells

    PubMed Central

    Siller, Richard; Greenhough, Sebastian; Naumovska, Elena; Sullivan, Gareth J.

    2015-01-01

    Summary The differentiation of pluripotent stem cells to hepatocytes is well established, yet current methods suffer from several drawbacks. These include a lack of definition and reproducibility, which in part stems from continued reliance on recombinant growth factors. This has remained a stumbling block for the translation of the technology into industry and the clinic for reasons associated with cost and quality. We have devised a growth-factor-free protocol that relies on small molecules to differentiate human pluripotent stem cells toward a hepatic phenotype. The procedure can efficiently direct both human embryonic stem cells and induced pluripotent stem cells to hepatocyte-like cells. The final population of cells demonstrates marker expression at the transcriptional and protein levels, as well as key hepatic functions such as serum protein production, glycogen storage, and cytochrome P450 activity. PMID:25937370

  12. Highly purified hexachlorobenzene induces cytochrome P4501A in primary cultures of chicken embryo hepatocytes

    SciTech Connect

    Mundy, Lukas J.; Jones, Stephanie P.; Crump, Doug; Herve, Jessica C.; Konstantinov, Alex; Utley, Fiona; Potter, David; Kennedy, Sean W.

    2010-11-01

    Some uncertainty exists regarding the purity of hexachlorobenzene (HCB) used in past toxicity studies. It has been suggested that reported toxic and biochemical effects initially attributed to HCB exposure may have actually been elicited by contamination of HCB by polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Herein, primary cultures of chicken embryo hepatocytes (CEH) were used to compare the potencies of two lots of reagent-grade hexachlorobenzene (HCB-old [HCB-O] and HCB-new [HCB-N]), highly purified HCB (HCB-P) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as inducers of ethoxyresorufin O-deethylase (EROD) activity, cytochrome P4501A4 (CYP1A4) messenger ribonucleic acid (mRNA) and CYP1A5 mRNA. The study also compared the EROD- and CYP1A4/5 mRNA-inducing potencies of HCB to the potencies of two mono-ortho substituted polychlorinated biphenyls (PCBs), 2,3,3',4,4'-pentachlorobiphenyl (PCB 105) and 2,3'4,4',5-pentachlorobiphenyl (PCB 118). HCB-O, HCB-N and HCB-P all induced EROD activity and up-regulated CYP1A4 and CYP1A5 mRNAs. Induction was not caused by contamination of HCB with PCDDs or PCDFs. Based upon a comparison of the EC{sub 50} and EC{sub threshold} values for EROD and CYP1A4/5 mRNA concentration-response curves, the potency of HCB relative to the potency of TCDD was 0.0001, and was similar to that of PCB 105 and PCB 118. The maximal EROD activity and CYP1A4/5 mRNA expression differed greatly between HCB and TCDD, and may contribute to an overestimation of the ReP value calculated for highly purified HCB.

  13. Structural specificity of steroids in stimulating DNA synthesis and protooncogene expression in primary rat hepatocyte cultures.

    PubMed

    Lee, C H; Edwards, A M

    2002-05-01

    Among the chemical compounds of varied structure which possess liver tumour-promoting are steroids, such as estrogens, pregnenolone derivatives and anabolic steroids. Although the mechanism(s) of tumour promotion in liver by these xenobiotics is not well understood, it is clear that growth stimulation is one important element in their action. As a basis for better defining whether steroids stimulate growth by a common mechanism or fall into sub-groups with differing actions, the effects of 46 steroids on DNA synthesis and the expression of protooncogenes c-fos and c-myc were examined in primary cultures of normal rat hepatocytes. Tentative groupings of steroids have been identified based on apparent structural requirements for stimulation of DNA synthesis, and effects of auxiliary factors in modulating this growth stimulus. For a "progestin" group, insulin appeared to be permissive for stimulation of DNA synthesis, and presence of an ester or hydroxyl group at 17alpha-position in combination with a non-polar group at C(6) appeared to be required for stimulation. For the pregnenes, dexamethasone was stimulatory. Structural requirements include a non-polar substitution at 16alpha-position and presence of a 6alpha-methyl group. Androgens were weak or ineffective stimulators of DNA synthesis. Anabolic steroids were weak to strong stimulators and alteration to A ring structure in combination with non-polar substitution at 17alpha-position appeared to be required for the activity. With the exception of the anabolic steroid, dianabol, there do not appear to be strong correlation between ability to stimulate DNA synthesis and ability to induce protooncogene expression among the steroids. This study provides a starting point for future more detailed examination of growth-stimulatory mechanism(s) of action of steroids in the liver. PMID:12127039

  14. Hepatic gene therapy: efficient gene delivery and expression in primary hepatocytes utilizing a conjugated adenovirus-DNA complex.

    PubMed Central

    Cristiano, R J; Smith, L C; Kay, M A; Brinkley, B R; Woo, S L

    1993-01-01

    Receptor-mediated endocytosis is an effective method for gene delivery into target cells. We have previously shown that DNA molecules complexed with asialoglycoprotein can be efficiently endocytosed by primary hepatocytes and the internalized DNA can be released from endosomes by the use of a replication-defective adenovirus. Because the DNA and virus enter target cells independently, activity enhancement requires high concentrations of adenoviral particles. In this study, adenoviral particles were chemically conjugated to poly(L-lysine) and bound ionically to DNA molecules. Quantitative delivery to primary hepatocytes was achieved with significantly reduced viral titer when the asialoorosomucoid-poly(L-lysine) conjugate was included in the complex. The conjugated adenovirus was used to deliver a DNA vector containing canine factor IX to mouse hepatocytes, resulting in the expression of significant concentrations of canine factor IX in the culture medium. The results suggest that receptor-mediated endocytosis coupled with an efficient endosomal lysis vector should permit the application of targeted and efficient gene delivery into the liver for gene therapy of hepatic deficiencies. Images Fig. 2 Fig. 4 PMID:8265587

  15. Retroviral insertional mutagenesis in telomerase-immortalized hepatocytes identifies RIPK4 as novel tumor suppressor in human hepatocarcinogenesis.

    PubMed

    Heim, D; Cornils, K; Schulze, K; Fehse, B; Lohse, A W; Brümmendorf, T H; Wege, H

    2015-01-15

    Carcinogenesis is a multistep process involving alterations in various cellular pathways. The critical genetic events driving the evolution of primary liver cancer, specifically hepatoblastoma and hepatocellular carcinoma (HCC), are still poorly understood. However, telomere stabilization is acknowledged as prerequisite for cancer progression in humans. In this project, human fetal hepatocytes were utilized as a cell culture model for untransformed, proliferating human liver cells, with telomerase activation as first oncogenic hit. To elucidate critical downstream genetic events driving further transformation of immortalized liver cells, we used retroviral insertional mutagenesis as an unbiased approach to induce genetic alterations. Following isolation of hyperproliferating, provirus-bearing cell clones, we monitored cancer-associated growth properties and characterized changes toward a malignant phenotype. Three transformed clones with the ability to form colonies in soft agar were expanded. As proof-of-principle for our experimental setup, we identified a transforming insertion on chromosome 8 within the pleiomorphic adenoma gene 1 (PLAG1), resulting in a 20-fold increase in PLAG1 expression. Upregulation of PLAG1 has already been described to promote human hepatoblastoma development. In a separate clone, a transforming insertion was detected in close proximity to the receptor-interacting serine-threonine kinase 4 (RIPK4) with an approximately eightfold suppression in RIPK4 expression. As validation for this currently unknown driver in hepatocarcinogenesis, we examined RIPK4 expression in human HCC samples and confirmed a significant suppression of RIPK4 in 80% of the samples. Furthermore, overexpression of RIPK4 in transformed human fetal hepatocytes resulted in an almost complete elimination of anchorage-independent growth. On the basis of these data, we propose RIPK4 as a novel putative tumor suppressor in human hepatocarcinogenesis. PMID:24413083

  16. Antioxidative effect of a chymotrypsin inhibitor from Momordica cochinchinensis (Cucurbitaceae) seeds in a primary rat hepatocyte culture.

    PubMed

    Tsoi, Alex Yuen-Kam; Ng, Tzi-Bun; Fong, Wing-Ping

    2005-10-01

    The antioxidative activity of a chymotrypsin-specific potato type I inhibitor from Momordica cochinchinensis (MCoCI) (Cucurbitaceae) has been investigated using the primary rat hepatocyte system. tert-Butyl hydroperoxide (t-BHP) was used to induce oxidative stress. Pretreatment of hepatocytes with MCoCI for 24 h significantly reversed t-BHP-induced cell damage, and the associated glutathione depletion and lipid peroxidation. The activities of glutathione-S-transferase and superoxide dismutase were also increased. These results suggested that MCoCI possessed antioxidative activity which may account for some of the pharmacological effects of Momordica cochinchinensis seeds, the traditional Chinese medicine known as Mubiezhi, from which MCoCI was isolated. PMID:15849778

  17. Characterizing the Effects of Heparin Gel Stiffness on Function of Primary Hepatocytes

    PubMed Central

    You, Jungmok; Park, Su-A; Shin, Dong-Sik; Patel, Dipali; Raghunathan, Vijay Krishna; Kim, Mihye; Murphy, Christopher J; Tae, Giyoong

    2013-01-01

    In the liver, hepatocytes are exposed to a large array of stimuli that shape hepatic phenotype. This in vivo microenvironment is lost when hepatocytes are cultured in standard cell cultureware, making it challenging to maintain hepatocyte function in vitro. Our article focused on one of the least studied inducers of the hepatic phenotype—the mechanical properties of the underlying substrate. Gel layers comprised of thiolated heparin (Hep-SH) and diacrylated poly(ethylene glycol) (PEG-DA) were formed on glass substrates via a radical mediated thiol–ene coupling reaction. The substrate stiffness varied from 10 to 110 kPa by changing the concentration of the precursor solution. ELISA analysis revealed that after 5 days, hepatocytes cultured on a softer heparin gel were synthesizing five times higher levels of albumin compared to those on a stiffer heparin gel. Immunofluorescent staining for hepatic markers, albumin and E-cadherin, confirmed that softer gels promoted better maintenance of the hepatic phenotype. Our findings point to the importance of substrate mechanical properties on hepatocyte function. PMID:23815179

  18. 17α-Ethinylestradiol (EE2) effect on global gene expression in primary rainbow trout (Oncorhynchus mykiss) hepatocytes.

    PubMed

    Hultman, Maria T; Song, You; Tollefsen, Knut Erik

    2015-12-01

    The potential impact of endocrine disrupting chemicals (EDCs) in the aquatic environment has driven the development of screening assays to evaluate the estrogenic properties of chemicals and their effects on aquatic organisms such as fish. However, obtaining full concentration-response relationships in animal (in vivo) exposure studies are laborious, costly and unethical, hence a need for developing feasible alternative (non-animal) methods. Use of in vitro bioassays such as primary fish hepatocytes, which retain many of the native properties of the liver, has been proposed for in vitro screening of estrogen receptor (ER) agonists and antagonists. The aim of present study was to characterize the molecular mode of action (MoA) of the ER agonist 17α-ethinylestradiol (EE2) in primary rainbow trout (Oncorhynchus mykiss) hepatocytes. A custom designed salmonid 60,000-feature (60k) oligonucleotide microarray was used to characterize the potential MoAs after 48h exposure to EE2. The microarray analysis revealed several concentration-dependent gene expression alterations including classical estrogen sensitive biomarker gene expression (e.g. estrogen receptor α, vitellogenin, zona radiata). Gene Ontology (GO) analysis displayed transcriptional changes suggesting interference of cellular growth, fatty acid and lipid metabolism potentially mediated through the estrogen receptor (ER), which were proposed to be associated with modulation of genes involved in endocrine function and reproduction. Pathway analysis supported the identified GOs and revealed modulation of additional genes associated with apoptosis and cholesterol biosynthesis. Differentially expressed genes (DEGs) related to impaired lipid metabolism (e.g. peroxisome proliferator-activated receptor α and γ), growth (e.g. insulin growth factor protein 1), phase I and II biotransformation (e.g. cytochrome P450 1A, sulfotransferase, UDP-glucuronosyltransferase and glutathione S-transferase) provided additional

  19. Hepatocytic Differentiation Potential of Human Fetal Liver Mesenchymal Stem Cells: In Vitro and In Vivo Evaluation

    PubMed Central

    Hamidouche, Zahia; Sokal, Etienne; Charbord, Pierre

    2016-01-01

    In line with the search of effective stem cell population that would progress liver cell therapy and because the rate and differentiation potential of mesenchymal stem cells (MSC) decreases with age, the current study investigates the hepatogenic differentiation potential of human fetal liver MSCs (FL-MSCs). After isolation from 11-12 gestational weeks' human fetal livers, FL-MSCs were shown to express characteristic markers such as CD73, CD90, and CD146 and to display adipocytic and osteoblastic differentiation potential. Thereafter, we explored their hepatocytic differentiation potential using the hepatogenic protocol applied for adult human liver mesenchymal cells. FL-MSCs differentiated in this way displayed significant features of hepatocyte-like cells as demonstrated in vitro by the upregulated expression of specific hepatocytic markers and the induction of metabolic functions including CYP3A4 activity, indocyanine green uptake/release, and glucose 6-phosphatase activity. Following transplantation, naive and differentiated FL-MSC were engrafted into the hepatic parenchyma of newborn immunodeficient mice and differentiated in situ. Hence, FL-MSCs appeared to be interesting candidates to investigate the liver development at the mesenchymal compartment level. Standardization of their isolation, expansion, and differentiation may also support their use for liver cell-based therapy development. PMID:27057173

  20. An in vitro examination of selenium-cadmium antagonism using primary cultures of rainbow trout (Oncorhynchus mykiss) hepatocytes.

    PubMed

    Jamwal, Ankur; Naderi, Mohammad; Niyogi, Som

    2016-02-17

    The present study evaluated the ameliorative properties of selenium (Se) against cadmium (Cd)-induced oxidative stress, using isolated rainbow trout (Oncorhynchus mykiss) hepatocytes in primary culture as the model experimental system. Cadmium (Cd) is known to induce cytotoxic effects by disrupting cellular oxidative homeostasis. On the other hand, selenium (Se) is an essential component of biological antioxidative machinery, and thus may provide protection against the toxic insults of Cd by augmenting the cellular antioxidant response. However, Se, when present above the threshold concentration, can also induce reactive oxygen species (ROS) generation and cause oxidative damage. In this experiment, trout hepatocytes in primary culture were exposed to 100 µM Cd, alone or in combination with different concentrations (25-500 µM) of selenite (SeO3(2-)) or selenomethionine (SeMet) for 48 h. Our findings indicated that both chemical forms of Se, at the lowest concentration used (25 µM), significantly reduced Cd-induced cytotoxicity (measured as cell viability). In contrast, Se at higher concentrations (≥50 µM) did not offer any protection against a Cd induced decrease in cell viability. The reduced cytotoxicity of Cd in the presence of 25 µM selenite or SeMet was associated with reduced intracellular ROS production, recovery of the cellular thiol status (ratio of reduced and oxidized glutathione), and amelioration in the activities of major enzymatic antioxidants (superoxide dismutase, catalase, and glutathione peroxidase). Co-treatment of hepatocytes with Cd and pharmacological antioxidants (TEMPO and NAC) also reduced Cd-induced oxidative stress in trout hepatocytes. This provided further evidence that Se likely ameliorates Cd toxicity via different antioxidative mechanisms. PMID:26673544

  1. Repression of multiple CYP2D genes in mouse primary hepatocytes with a single siRNA construct.

    PubMed

    Elraghy, Omaima; Baldwin, William S

    2015-01-01

    The Cyp2d subfamily is the second most abun-dant subfamily of hepatic drug-metabolizing CYPs. In mice, there are nine Cyp2d members that are believed to have redundant catalytic activity. We are testing and optimizing the ability of one short interfering RNA (siRNA) construct to knockdown the expression of multiple mouse Cyp2ds in primary hepatocytes. Expression of Cyp2d10, Cyp2d11, Cyp2d22, and Cyp2d26 was observed in the primary male mouse hepatocytes. Cyp2d9, which is male-specific and growth hormone-dependent, was not expressed in male primary hepatocytes, potentially because of its dependence on pulsatile growth hormone release from the anterior pituitary. Several different siRNAs at different concentrations and with different reagents were used to knockdown Cyp2d expression. siRNA constructs designed to repress only one construct often mildly repressed several Cyp2d isoforms. A construct designed to knockdown every Cyp2d isoform provided the best results, especially when incubated with transfection reagents designed specifically for primary cell culture. Interestingly, a construct designed to knockdown all Cyp2d isoforms, except Cyp2d10, caused a 2.5× increase in Cyp2d10 expression, presumably because of a compensatory response. However, while RNA expression is repressed 24 h after siRNA treatment, associated changes in Cyp2d-mediated metabolism are tenuous. Overall, this study provides data on the expression of murine Cyp2ds in primary cell lines, valuable information on designing siRNAs for silencing multiple murine CYPs, and potential pros and cons of using siRNA as a tool for repressing Cyp2d and estimating Cyp2d's role in murine xenobiotic metabolism. PMID:25124873

  2. BOLISM OF ARSENITE IN CULTURED PRIMARY HEPATOCYTES FROM SIX MAMMALIAN SPECIES

    EPA Science Inventory

    Inorganic arsenic (iAs) is an environmental toxin and carcinogen. Biomethylation is the major pathway for the metabolism of iAs in many mammalian species, including the human. The liver is considered the primary site for iAs methylation and As (+3 oxidation state) methyltransfera...

  3. Assessing the therapeutic potential of lab-made hepatocytes.

    PubMed

    Rezvani, Milad; Grimm, Andrew A; Willenbring, Holger

    2016-07-01

    Hepatocyte transplantation has potential as a bridge or even alternative to whole-organ liver transplantation. Because donor livers are scarce, realizing this potential requires the development of alternative cell sources. To be therapeutically effective, surrogate hepatocytes must replicate the complex function and ability to proliferate of primary human hepatocytes. Ideally, they are also autologous to eliminate the need for immune suppression, which can have severe side effects and may not be sufficient to prevent rejection long term. In the past decade, several methods have been developed to generate hepatocytes from other readily and safely accessible somatic cells. These lab-made hepatocytes show promise in animal models of liver diseases, supporting the feasibility of autologous liver cell therapies. Here, we review recent preclinical studies exemplifying different types of lab-made hepatocytes that can potentially be used in autologous liver cell therapies. To define the therapeutic efficacy of current lab-made hepatocytes, we compare them to primary human hepatocytes, focusing on engraftment efficiency and posttransplant proliferation and function. In addition to summarizing published results, we discuss animal models and assays effective in assessing therapeutic efficacy. This analysis underscores the therapeutic potential of current lab-made hepatocytes, but also highlights deficiencies and uncertainties that need to be addressed in future studies aimed at developing liver cell therapies with lab-made hepatocytes. (Hepatology 2016;64:287-294). PMID:27014802

  4. DNA Adduct Formation of 4-Aminobiphenyl and Heterocyclic Aromatic Amines in Human Hepatocytes

    PubMed Central

    Nauwelaers, Gwendoline; Bessette, Erin E.; Gu, Dan; Tang, Yijin; Rageul, Julie; Fessard, Valérie; Yuan, Jian-Min; Yu, Mimi C.; Langouët, Sophie; Turesky, Robert J.

    2011-01-01

    DNA adduct formation of the aromatic amine, 4-aminobiphenyl (4-ABP), a known human carcinogen present in tobacco smoke, and the heterocyclic aromatic amines (HAAs), 2-amino-9H-pyrido[2,3-b]indole (AαC), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), and 2-amino-3,8-dimethylmidazo[4,5-f]quinoxaline (MeIQx), potential human carcinogens, which are also present in tobacco smoke or formed during the high-temperature cooking of meats, was investigated in freshly cultured human hepatocytes. The carcinogens (10 μM) were incubated with hepatocytes derived from eight different donors for time periods up to 24 h. The DNA adducts were quantified by liquid chromatography-electrospray ionization mass spectrometry with a linear quadrupole ion trap mass spectrometer. The principal DNA adducts formed for all of the carcinogens were N-(deoxyguanosin-8-yl) (dG-C8) adducts. The levels of adducts ranged from 3.4 to 140 adducts per 107 DNA bases. The highest level of adduct formation occurred with AαC, followed by 4-ABP, then by PhIP, MeIQx, and IQ. Human hepatocytes formed dG-C8-HAA-adducts at levels that were up to 100-fold greater than the amounts of adducts produced in rat hepatocytes. In contrast to HAA adducts, the levels of dG-C8-4-ABP adduct formation were similar in human and rat hepatocytes. These DNA binding data demonstrate that the rat, an animal model that is used for carcinogenesis bioassays, significantly underestimates the potential hepatic genotoxicity of HAAs in humans. The high level of DNA adducts formed by AαC, a carcinogen produced in tobacco smoke at levels that are up to 100-fold higher than the amounts of 4-ABP, is noteworthy. The possible causal role of AαC in tobacco-associated cancers warrants investigation. PMID:21456541

  5. Direct Reprogramming of Human Fibroblasts to Hepatocyte-Like Cells by Synthetic Modified mRNAs

    PubMed Central

    Simeonov, Kamen P.; Uppal, Hirdesh

    2014-01-01

    Direct reprogramming by overexpression of defined transcription factors is a promising new method of deriving useful but rare cell types from readily available ones. While the method presents numerous advantages over induced pluripotent stem (iPS) cell approaches, a focus on murine conversions and a reliance on retroviral vectors limit potential human applications. Here we address these concerns by demonstrating direct conversion of human fibroblasts to hepatocyte-like cells via repeated transfection with synthetic modified mRNAs. Hepatic induction was achieved with as little as three transcription factor mRNAs encoding HNF1A plus any two of the factors, FOXA1, FOXA3, or HNF4A in the presence of an optimized hepatic growth medium. We show that the absolute necessity of exogenous HNF1A mRNA delivery is explained both by the factor's inability to be activated by any other factors screened and its simultaneous ability to strongly induce expression of other master hepatic transcription factors. Further analysis of factor interaction showed that a series of robust cross-activations exist between factors that induce a hepatocyte-like state. Transcriptome and small RNA sequencing during conversion toward hepatocyte-like cells revealed global preferential activation of liver genes and miRNAs over those associated with other endodermal tissues, as well as downregulation of fibroblast-associated genes. Induced hepatocyte-like cells also exhibited hepatic morphology and protein expression. Our data provide insight into the process by which direct hepatic reprogramming occurs in human cells. More importantly, by demonstrating that it is possible to achieve direct reprogramming without the use of retroviral gene delivery, our results supply a crucial step toward realizing the potential of direct reprogramming in regenerative medicine. PMID:24963715

  6. DHA down-regulates phenobarbital-induced cytochrome P450 2B1 gene expression in rat primary hepatocytes by attenuating CAR translocation

    SciTech Connect

    Li, C.-C.; Lii, C.-K.; Liu, K.-L.; Yang, J.-J.; Chen, H.-W.

    2007-12-15

    The constitutive androstane receptor (CAR) plays an important role in regulating the expression of detoxifying enzymes, including cytochrome P450 2B (CYP 2B). Phenobarbital (PB) induction of human CYP 2B6 and mouse CYP 2b10 has been shown to be mediated by CAR. Our previous study showed that PB-induced CYP 2B1 expression in rat primary hepatocytes is down-regulated by both n-6 and n-3 polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA); however, the mechanism for this down-regulation by DHA was previously unknown. The objective of the present study was to determine whether change in CAR translocation is involved in the down-regulation by n-6 and n-3 PUFAs of PB-induced CYP 2B1 expression in rat primary hepatocytes. We used 100 {mu}M arachidonic acid, linoleic acid, eicosapentaenoic acid, and DHA to test this hypothesis. PB triggered the translocation of CAR from the cytosol into the nucleus in a dose-dependent and time-dependent manner in our hepatocyte system, and the CAR distribution in rat primary hepatocytes was significantly affected by DHA. DHA treatment decreased PB-inducible accumulation of CAR in the nuclear fraction and increased it in the cytosolic fraction in a dose-dependent manner. The down-regulation of CYP 2B1 expression by DHA occurred in a dose-dependent manner, and a similar pattern was found for the nuclear accumulation of CAR. The results of immunoprecipitation showed a CAR/RXR heterodimer bound to nuclear receptor binding site 1 (NR-1) of the PB-responsive enhancer module (PBREM) of the CYP 2B1gene. The EMSA results showed that PB-induced CAR binding to NR-1 was attenuated by DHA. Taken together, these results suggest that attenuation of CAR translocation and decreased subsequent binding to NR-1 are involved in DHA's down-regulation of PB-induced CYP 2B1 expression.

  7. Primary cultured cells as sensitive in vitro model for assessment of toxicants--comparison to hepatocytes and gill epithelia.

    PubMed

    Zhou, Bingsheng; Liu, Chunsheng; Wang, Jingxian; Lam, Paul K S; Wu, Rudolf S S

    2006-11-16

    In an effort to develop cultured cell models for toxicity screening and environmental biomonitoring, we compared primary cultured gill epithelia and hepatocytes from freshwater tilapia (Oreochromis niloticus) to assess their sensitivity to AhR agonist toxicants. Epithelia were cultured on permeable supports (terephthalate membranes, "filters") and bathed on the apical with waterborne toxicants (pseudo in vivo asymmetrical culture conditions). Hepatocytes were cultured in multi-well plates and exposed to toxicants in culture medium. Cytochrome P4501A (measured as 7-Ethoxyresorufin-O-deethylase, EROD) was selected as a biomarker. For cultured gill epithelia, the integrity of the epithelia remained unchanged on exposure to model toxicants, such as 1,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), benzo(a)pyrene B[a]P, polychlorinated biphenyl (PCB) mixture (Aroclor 1254), and polybrominated diphenyl ether (PBDE) mixture (DE71). A good concentration-dependent response of EROD activity was clearly observed in both cultured gill epithelia and hepatocytes. The time-course response of EROD was measured as early as 3h, and was maximal after 6h of exposure to TCDD, B[a]P and Aroclor 1254. The estimated 6h EC50 for TCDD, B[a]P, and Aroclor 1254 was 1.2 x 10(-9), 5.7 x 10(-8) and 6.6 x 10(-6)M. For the cultured hepatocytes, time-course study showed that a significant induction of EROD took place at 18 h, and the maximal induction of EROD was observed at 24h after exposure. The estimated 24h EC50 for TCDD, B[a]P, and Aroclor 1254 was 1.4 x 10(-9), 8.1 x 10(-8) and 7.3 x 10(-6)M. There was no induction or inhibition of EROD in DE71 exposure to both gill epithelia and hepatocytes. The results show that cultured gill epithelia more rapidly induce EROD and are slightly more sensitive than cultured hepatocytes, and could be used as a rapid and sensitive tool for screening chemicals and monitoring environmental AhR agonist toxicants. PMID:16959333

  8. Contribution of CNT1 and ENT1 to ribavirin uptake in human hepatocytes.

    PubMed

    Choi, Min-Koo; Kim, Min-Hye; Maeng, Han-Joo; Song, Im-Sook

    2015-01-01

    The objective of this study was to investigate the contributions of a sodium-dependent concentrative nucleoside transporter (CNT) 1 and an equilibrative nucleoside transporter (ENT) 1 to ribavirin uptake in human hepatocytes. The initial studies in oocytes expressing CNT1 and ENT1 showed increases in ribavirin uptake, indicating that ribavirin was a substrate for both CNT1 and ENT1. The CNT1- and ENT1-mediated ribavirin uptake showed concentration dependency with the following kinetics parameters: Km 26.3 μM and Vmax 426.2 fmol/min/oocyte for CNT1; Km 70.5 μM and Vmax 134.3 fmol/min/oocyte for ENT1. Ribavirin uptake clearance in six human hepatocytes ranged from 21.3 to 300.7 μL/min. Estimation of the contributions of CNT1 and ENT1 to the hepatic uptake of ribavirin by using a relative activity factor method indicated that the relative contribution of ENT1 to the ribavirin uptake was 82.8 ± 3.9%. Real-time polymerase chain reaction analysis of CNT1 and ENT1 expressions in the hepatocytes showed that ENT1 mRNA expression was closely correlated with ribavirin uptake (R = 0.95, P = 0.003) while CNT1 was not. The findings indicated that ENT1 was the major transporter controlling the hepatic uptake of ribavirin. PMID:25011570

  9. Microarray analyses and molecular profiling of steatosis induction in immortalized human hepatocytes.

    PubMed

    De Gottardi, Andrea; Vinciguerra, Manlio; Sgroi, Antonino; Moukil, Moulay; Ravier-Dall'Antonia, Florence; Pazienza, Valerio; Pugnale, Paolo; Foti, Michelangelo; Hadengue, Antoine

    2007-08-01

    Hepatic steatosis is an important risk factor for the development of inflammation, fibrosis and impaired liver regeneration. The factors regulating lipid accumulation and driving hepatic steatosis toward inflammation, fibrosis and impaired regeneration are largely unknown. The aim of this study was to identify major alterations in gene expression occurring in steatotic hepatocytes, and to analyze how these changes impact cellular processes associated with steatosis. Microarray gene chips and RT-PCR were performed to analyze changes in gene expression induced in fatty human immortalized hepatocytes after treatment with 50 muM oleic acid for 7 days. Lipid metabolism and triglyceride accumulation in these cells was examined by Oil-Red-O staining, thin-layer chromatography (TLC) and immunofluorescence. Caspase 3 activity, BrdU incorporation and trypan blue exclusion were used to study apoptosis, proliferation and cell viability. Finally, quantitative analysis of signalling induced by insulin was performed by Western blot. Characterization of steatosis in three hepatocyte-derived cell lines indicated that the immortalized human hepatocytes (IHH) line was the most appropriate cell line for this study. Gene expression analysis showed significant alterations in the transcription of two major classes of genes involved either in cholesterol and fatty acid biosynthesis, as well as lipid export, or in apoptosis and cell proliferation. Such changes were functionally relevant, since TLC indicated that synthesis and accumulation of triglycerides were increased in steatotic cells, while synthesis of cholesterol and fatty acids were decreased. Lipid accumulation in IHH was associated with an increased apoptosis and an inhibition of cell proliferation and viability. No detectable changes in genes associated with insulin resistance were observed in steatotic cells, but signalling induced by insulin was more efficient in steatotic IHH as compared to control cells. We conclude that IHH

  10. Toxicity of green tea extracts and their constituents in rat hepatocytes in primary culture.

    PubMed

    Schmidt, M; Schmitz, H-J; Baumgart, A; Guédon, D; Netsch, M I; Kreuter, M-H; Schmidlin, C B; Schrenk, D

    2005-02-01

    Recent reports on sporadic cases of liver disorders (acute hepatitis, icterus, hepatocellular necrosis) after ingestion of dietary supplements based on hydro-alcoholic extracts from green tea leaves led to restrictions of the marketing of such products in certain countries of the EU. Since green tea is considered to exert a number of beneficial health effects, and, therefore, green tea products are widely used as dietary supplements, we were interested in the possible mechanism of hepatotoxicity of green tea extracts and in the components involved in such effects. Seven hours after seeding on collagen, rat hepatocytes in primary culture were treated with various hydro-alcoholic green tea extracts (two different native 80% ethanolic dry extracts and an 80% ethanolic dry extract cleared from lipophilic compounds). Cells were washed, and reduction of resazurin, used as a viability parameter monitoring intact mitochondrial function, was determined. It was found that all seven green tea extracts examined enhanced resazurin reduction significantly at a concentration range of 100-500 microg/ml medium, while a significant decrease was observed at 1-3mg/ml medium. Decreased levels were concomitant with abundant necrosis as observed by microscopic inspection of the cultures and with increased leakage of lactate dehydrogenase activity from the cells. In a separate series of experiments, the green tea constituents (-)-epicatechin, (-)-epigallocatechin-3-gallate, caffeine and theanine were tested at concentrations reflecting their levels in a typical green tea extract. Synthetic (+)-epigallocatechin (200 microM) was used for comparison. Cytotoxicity was found with (-)-epigallocatechin-3-gallate only. The concomitant addition of 0.25 mM ascorbate/0.05 mM alpha-tocopherol had no influence on cytotoxicity. In conclusion, our results suggest that high concentrations of green tea extract can exert acute toxicity in rat liver cells. (-)-Epigallocatechin-3-gallate seems to be a key

  11. Ferritin-stimulated lipid peroxidation, lysosomal leak, and macroautophagy promote lysosomal "metastability" in primary hepatocytes determining in vitro cell survival.

    PubMed

    Krenn, Margit A; Schürz, Melanie; Teufl, Bernhard; Uchida, Koji; Eckl, Peter M; Bresgen, Nikolaus

    2015-03-01

    Several pathologies are associated with elevated levels of serum ferritin, for which growth inhibitory properties have been reported; however, the underlying mechanisms are still poorly defined. Previously we have described cytotoxic properties of isoferritins released from primary hepatocytes in vitro, which induce apoptosis in an iron and oxidative stress-dependent mode. Here we show that this ferritin species stimulates endosome clustering and giant endosome formation in primary hepatocytes accompanied by enhanced lysosomal membrane permeability (LMP). In parallel, protein modification by lipid peroxidation-derived 4-hydroxynonenal (HNE) is strongly promoted by ferritin, the HNE-modified proteins (HNE-P) showing remarkable aggregation. Emphasizing the prooxidant context, GSH is rapidly depleted and the GSH/GSSG ratio is substantially declining in ferritin-treated cells. Furthermore, ferritin triggers a transient upregulation of macroautophagy which is abolished by iron chelation and apparently supports HNE-P clearance. Macroautophagy inhibition by 3-methyladenine strongly amplifies ferritin cytotoxicity in a time- and concentration-dependent mode, suggesting an important role of macroautophagy on cellular responses to ferritin endocytosis. Moreover, pointing at an involvement of lysosomal proteolysis, ferritin cytotoxicity and lysosome fragility are aggravated by the protease inhibitor leupeptin. In contrast, EGF which suppresses ferritin-induced cell death attenuates ferritin-mediated LMP. In conclusion, we propose that HNE-P accumulation, lysosome dysfunction, and macroautophagy stimulated by ferritin endocytosis provoke lysosomal "metastability" in primary hepatocytes which permits cell survival as long as in- and extrinsic determinants (e.g., antioxidant availability, damage repair, EGF signaling) keep the degree of lysosomal destabilization below cell death-inducing thresholds. PMID:25532933

  12. Expression and characterization of biologically active human hepatocyte growth factor (HGF) by insect cells infected with HGF-recombinant baculovirus.

    PubMed

    Yee, C J; DeFrances, M C; Bell, A; Bowen, W; Petersen, B; Michalopoulos, G K; Zarnegar, R

    1993-08-10

    A cDNA containing the entire coding sequence of human hepatocyte growth factor (HGF) [also known as scatter factor (SF)] was inserted into the genome of Autographa california nuclear polyhedrosis virus (baculovirus) adjacent to the polyhedrin promoter by homologous recombination. Insect cells (Spodoptera frugiperda) infected with the recombinant virus secrete relatively high levels (3-8 mg/L) of biologically active HGF into the culture medium. The recombinant HGF induces pronounced morphological changes and scattering of primary cultures of rat, mouse, and human hepatocytes within 24 h after plating and stimulates DNA synthesis in these cells with the same magnitude as native HGF derived from human placenta or rabbit serum. The human recombinant HGF produced by the insect cells is N-glycosylated, binds to heparin like native HGF, and is recognized by polyclonal antiserums raised against human or rabbit HGF as assessed by immunoblot, ELISA, and immunoneutralization experiments. Metabolic radiolabeling with L-[35S]methionine (pulse-chase experiments) as well as Western blot analysis indicates that the recombinant HGF is synthesized and secreted by the infected insect cells as the unprocessed single-chain form (pro-HGF) when the cells are cultured in serum-free medium. However, when the infected insect cells are cultured in insect culture medium (Grace's medium) containing fetal bovine serum, the secreted HGF is present mainly in the mature heterodimeric form. Addition of serum to the baculovirus-expressed single-chain [125I]HGF in a cell-free system results in conversion to the heterodimeric two-chain form, and the activation is prevented by the serine protease inhibitor PMSF. Incubation of 125I-labeled pro-HGF with rat liver or spleen extracts resulted in conversion of pro-HGF to the heterodimeric two-chain form. A truncated form of HGF containing the N-terminal portion of HGF (kringles 1-3) was also produced in the same expression system. This deleted HGF, by

  13. Genes for the dimerization cofactor of hepatocyte nuclear factor-1[alpha] (DCOH) are on human and murine chromsomes 10

    SciTech Connect

    Milatovich, A.; Mendel, D.B.; Crabtree, G.R.; Francke, U. )

    1993-04-01

    Hepatocyte nuclear factor-1[alpha] (HNF-1[alpha]; gene symbol, TCF1) forms dimers with itself as well as with HNF-1[beta] and regulates the expression of several liver-specific genes. Recently, a dimerization cofactor of hepatocyte nuclear factor-1[alpha], called DCOH, has been identified. Here, the authors report the chromosomal localization of the genes for this cofactor to chromosomes 10 in both humans and mice by Southern blot analyses of somatic cell hybrids. 25 refs., 1 fig., 2 tabs.

  14. Metabolism of Oxycodone in Human Hepatocytes from Different Age Groups and Prediction of Hepatic Plasma Clearance

    PubMed Central

    Korjamo, Timo; Tolonen, Ari; Ranta, Veli-Pekka; Turpeinen, Miia; Kokki, Hannu

    2012-01-01

    Oxycodone is commonly used to treat severe pain in adults and children. It is extensively metabolized in the liver in adults, but the maturation of metabolism is not well understood. Our aim was to study the metabolism of oxycodone in cryopreserved human hepatocytes from different age groups (3 days, 2 and 5 months, 4 years, adult pool) and predict hepatic plasma clearance of oxycodone using these data. Oxycodone (0.1, 1, and 10 μM) was incubated with hepatocytes for 4 h, and 1 μM oxycodone also with CYP3A inhibitor ketoconazole (1 μM). Oxycodone and noroxycodone concentrations were determined at several time points with liquid chromatography–mass spectrometry. In vitro clearance of oxycodone was used to predict hepatic plasma clearance, using the well-stirred model and published physiological parameters. Noroxycodone was the major metabolite in all batches and ketoconazole inhibited the metabolism markedly in most cases. A clear correlation between in vitro oxycodone clearance and CYP3A4 activity was observed. The predicted hepatic plasma clearances were typically much lower than the published median total plasma clearance from pharmacokinetic studies. The data suggests that there are no children-specific metabolites of oxycodone. Moreover, CYP3A activity seems to be the major determinant in metabolic clearance of oxycodone regardless of age group or individual variability in hepatocyte batches. PMID:22291644

  15. Activation of the Constitutive Androstane Receptor Inhibits Gluconeogenesis without Affecting Lipogenesis or Fatty Acid Synthesis in Human Hepatocytes

    PubMed Central

    Lynch, Caitlin; Pan, Yongmei; Li, Linhao; Heyward, Scott; Moeller, Timothy; Swaan, Peter W.; Wang, Hongbing

    2014-01-01

    Objective Accumulating evidence suggests that activation of mouse constitutive androstane receptor (mCAR) alleviates type 2 diabetes and obesity by inhibiting hepatic gluconeogenesis, lipogenesis, and fatty acid synthesis. However, the role of human (h) CAR in energy metabolism is largely unknown. The present study aims to investigate the effects of selective hCAR activators on hepatic energy metabolism in human primary hepatocytes (HPH). Methods Ligand-based structure-activity models were used for virtual screening of the Specs database (www.specs.net) followed by biological validation in cell-based luciferase assays. The effects of two novel hCAR activators (UM104 and UM145) on hepatic energy metabolism were evaluated in HPH. Results Real-time PCR and Western blotting analyses reveal that activation of hCAR by UM104 and UM145 significantly repressed the expression of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, two pivotal gluconeogenic enzymes, while exerting negligible effects on the expression of genes associated with lipogenesis and fatty acid synthesis. Functional experiments show that UM104 and UM145 markedly inhibit hepatic synthesis of glucose but not triglycerides in HPH. In contrast, activation of mCAR by 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene, a selective mCAR activator, repressed the expression of genes associated with gluconeogenesis, lipogenesis, and fatty acid synthesis in mouse primary hepatocytes, which were consistent with previous observations in mouse model in vivo. Conclusion Our findings uncover an important species difference between hCAR and mCAR in hepatic energy metabolism, where hCAR selectively inhibits gluconeogenesis without suppressing fatty acid synthesis. Implications Such species selectivity should be considered when exploring CAR as a potential therapeutic target for metabolic disorders. PMID:24878338

  16. Improved protocols for protein and RNA isolation from three-dimensional collagen sandwich cultures of primary hepatocytes.

    PubMed

    Heidebrecht, F; Schulz, I; Keller, M; Behrens, S-E; Bader, A

    2009-10-01

    The sandwich culture is the most widely used long-term culture system for functional primary hepatocytes. Despite its advantages, the currently available protocols for protein and RNA extraction are either time-consuming or contain steps that may skewer the results. This paper describes improved protocols for RNA and protein extraction from sandwich cultures that are easy to perform, require short working time, and use no additional enzymatic reactions that could change the expression profile of the cells. The quality of the RNA is excellent, allowing also applications requiring high purity such as microarrays. In general, the protocols are suited for any cells in 3D collagen culture. PMID:19539596

  17. Identification of early target genes of aflatoxin B1 in human hepatocytes, inter-individual variability and comparison with other genotoxic compounds

    SciTech Connect

    Josse, Rozenn; Dumont, Julie; Fautrel, Alain; Robin, Marie-Anne; Guillouzo, André

    2012-01-15

    Gene expression profiling has recently emerged as a promising approach to identify early target genes and discriminate genotoxic carcinogens from non-genotoxic carcinogens and non-carcinogens. However, early gene changes induced by genotoxic compounds in human liver remain largely unknown. Primary human hepatocytes and differentiated HepaRG cells were exposed to aflatoxin B1 (AFB1) that induces DNA damage following enzyme-mediated bioactivation. Gene expression profile changes induced by a 24 h exposure of these hepatocyte models to 0.05 and 0.25 μM AFB1 were analyzed by using oligonucleotide pangenomic microarrays. The main altered signaling pathway was the p53 pathway and related functions such as cell cycle, apoptosis and DNA repair. Direct involvement of the p53 protein in response to AFB1 was verified by using siRNA directed against p53. Among the 83 well-annotated genes commonly modulated in two pools of three human hepatocyte populations and HepaRG cells, several genes were identified as altered by AFB1 for the first time. In addition, a subset of 10 AFB1-altered genes, selected upon basis of their function or tumor suppressor role, was tested in four human hepatocyte populations and in response to other chemicals. Although they exhibited large variable inter-donor fold-changes, several of these genes, particularly FHIT, BCAS3 and SMYD3, were found to be altered by various direct and other indirect genotoxic compounds and unaffected by non-genotoxic compounds. Overall, this comprehensive analysis of early gene expression changes induced by AFB1 in human hepatocytes identified a gene subset that included several genes representing potential biomarkers of genotoxic compounds. -- Highlights: ► Gene expression profile changes induced by aflatoxin B1 in human hepatocytes. ► AFB1 modulates various genes including tumor suppressor genes and proto-oncogenes. ► Important inter-individual variations in the response to AFB1. ► Some genes also altered by other

  18. Dichloroacetate Stimulates Glycogen Accumulation in Primary Hepatocytes through an Insulin-Independent Mechanism

    SciTech Connect

    Lingohr, Melissa K.; Bull, Richard J.; Kato-Weinstein, Junko; Thrall, Brian D. )

    2002-01-01

    Dichloroacetate (DCA), a by-product of water chlorination, causes liver cancer in B6C3F1 mice. A hallmark response observed in mice exposed to carcinogenic doses of DCA is an accumulation of hepatic glycogen content. To distinguish whether the in vivo glycogenic effect of DCA was dependent on insulin and insulin signaling proteins, experiments were conducted in isolated hepatocytes where insulin concentrations could be controlled. In hepatocytes isolated from male B6C3F1 mice, DCA increased glycogen levels in a dose-related manner, independently of insulin. The accumulation of hepatocellular glycogen induced by DCA was not the result of decreased glycogenolysis, since DCA had no effect on the rate of glucagon-stimulated glycogen breakdown. Glycogen accumulation caused by DCA treatment was not hindered by inhibitors of extracellular-regulated protein kinase kinase (Erk1/2 kinase or MEK) or p70 kDa S6 protein kinase (p70(S6K)), but was completely blocked by the phosphatidylinositol 3-kinase (PI3K) inhibitors, LY294002 and wortmannin. Similarly, insulin-stimulated glycogen deposition was not influenced by the Erk1/2 kinase inhibitor, PD098509, or the p70(S6K) inhibitor, rapamycin. Unlike DCA-stimulated glycogen deposition, PI3K-inhibition only partially blocked the glycogenic effect of insulin. DCA did not cause phosphorylation of the downstream PI3K target protein, protein kinase B (PKB/Akt). The phosphorylation of PKB/Akt did not correlate to insulin-stimulated glycogenesis either. Similar to insulin, DCA in the medium decreased IR expression in isolated hepatocytes. The results indicate DCA increases hepatocellular glycogen accumulation through a PI3K-dependent mechanism that does not involve PKB/Akt and is, at least in part, different from the classical insulin-stimulated glycogenesis pathway. Somewhat surprisingly, insulin-stimulated glycogenesis also appears not to involve PKB/Akt in isolated murine hepatocytes.

  19. Integrated Transcriptional and Proteomic Analysis with In Vitro Biochemical Assay Reveal the Important Role of CYP3A46 in T-2 Toxin Hydroxylation in Porcine Primary Hepatocytes*

    PubMed Central

    Wang, Jianshe; Jiang, Jun; Zhang, Hongxia; Wang, Junping; Cai, Hua; Li, Cheng; Li, Kangbai; Liu, Jing; Guo, Xuejiang; Zou, Guangxun; Wang, Dazhi; Deng, Yiqun; Dai, Jiayin

    2011-01-01

    Both T-2 toxin and its metabolites are highly potent mycotoxins that can cause severe human and animal diseases upon exposure. Understanding the toxic mechanism and biotransformation process of T-2 toxin at a cellular level is essential for the development of counter-measures. We investigated the effect of T-2 toxin in porcine primary hepatocytes using porcine genome array and two-dimensional difference gel electrophoresis with matrix-assisted laser desorption/ionization tandem time of flight mass spectrometry. Integrated transcriptional and proteomic analysis demonstrated that T-2 toxin adversely affected porcine hepatocytes by initiating lipid metabolism disorder, oxidative stress response, and apoptosis. In addition, xenobiotic metabolism genes, including cytochrome P450 3As (CYP3A46 and CYP3A39), carboxylesterase 1Cs (CES1C4 and CES1C5), and epoxide hydrolase (EPHX1), increased in T-2 toxin treatment cells. Using HepG2 cells to over-express the recombinant xenobiotic metabolism genes above and rapid resolution liquid chromatography/tandem mass spectrometry to detect metabolites of T-2 toxin, we determined that porcine CYP3A46 mainly catalyzed T-2 to form 3′-hydroxy-T-2, which was further confirmed by purified CYP3A46 protein. However, recombinant porcine CES1C5 and EPHX1 did not enhance hydrolysis and de-epoxidation of T-2 implying that other esterases and epoxide hydrolases may play dominant roles in those reactions. PMID:21685020

  20. Prediction of Drug-Induced Liver Injury in Micropatterned Co-cultures Containing iPSC-Derived Human Hepatocytes.

    PubMed

    Ware, Brenton R; Berger, Dustin R; Khetani, Salman R

    2015-06-01

    Primary human hepatocytes (PHHs) are a limited resource for drug screening, their quality for in vitro use can vary considerably across different lots, and a lack of available donor diversity restricts our understanding of how human genetics affect drug-induced liver injury (DILI). Induced pluripotent stem cell-derived human hepatocyte-like cells (iPSC-HHs) could provide a complementary tool to PHHs for high-throughput drug screening, and ultimately enable personalized medicine. Here, we hypothesized that previously developed iPSC-HH-based micropatterned co-cultures (iMPCCs) with murine embryonic fibroblasts could be amenable to long-term drug toxicity assessment. iMPCCs, created in industry-standard 96-well plates, were treated for 6 days with a set of 47 drugs, and multiple functional endpoints (albumin, urea, ATP) were evaluated in dosed cultures against vehicle-only controls to enable binary toxicity decisions. We found that iMPCCs correctly classified 24 of 37 hepatotoxic drugs (65% sensitivity), while all 10 non-toxic drugs tested were classified as such in iMPCCs (100% specificity). On the other hand, conventional confluent cultures of iPSC-HHs failed to detect several liver toxins that were picked up in iMPCCs. Results for DILI detection in iMPCCs were remarkably similar to published data in PHH-MPCCs (65% versus 70% sensitivity) that were dosed with the same drugs. Furthermore, iMPCCs detected the relative hepatotoxicity of structural drug analogs and recapitulated known mechanisms of acetaminophen toxicity in vitro. In conclusion, iMPCCs could provide a robust tool to screen for DILI potential of large compound libraries in early stages of drug development using an abundant supply of commercially available iPSC-HHs. PMID:25716675

  1. Robust generation of hepatocyte-like cells from human embryonic stem cell populations.

    PubMed

    Medine, Claire N; Lucendo-Villarin, Baltasar; Zhou, Wenli; West, Christopher C; Hay, David C

    2011-01-01

    Despite progress in modelling human drug toxicity, many compounds fail during clinical trials due to unpredicted side effects. The cost of clinical studies are substantial, therefore it is essential that more predictive toxicology screens are developed and deployed early on in drug development (Greenhough et al 2010). Human hepatocytes represent the current gold standard model for evaluating drug toxicity, but are a limited resource that exhibit variable function. Therefore, the use of immortalised cell lines and animal tissue models are routinely employed due to their abundance. While both sources are informative, they are limited by poor function, species variability and/or instability in culture (Dalgetty et al 2009). Pluripotent stem cells (PSCs) are an attractive alternative source of human hepatocyte like cells (HLCs) (Medine et al 2010). PSCs are capable of self renewal and differentiation to all somatic cell types found in the adult and thereby represent a potentially inexhaustible source of differentiated cells. We have developed a procedure that is simple, highly efficient, amenable to automation and yields functional human HLCs (Hay et al 2008 ; Fletcher et al 2008 ; Hannoun et al 2010 ; Payne et al 2011 and Hay et al 2011). We believe our technology will lead to the scalable production of HLCs for drug discovery, disease modeling, the construction of extra-corporeal devices and possibly cell based transplantation therapies. PMID:22064456

  2. Establishment of a primary hepatocyte culture from the small Indian mongoose (Herpestes auropunctatus) and distribution of mercury in liver tissue.

    PubMed

    Horai, Sawako; Yanagi, Kumiko; Kaname, Tadashi; Yamamoto, Masatatsu; Watanabe, Izumi; Ogura, Go; Abe, Shintaro; Tanabe, Shinsuke; Furukawa, Tatsuhiko

    2014-11-01

    The present study established a primary hepatocyte culture for the small Indian mongoose (Herpestes auropunctatus). To determine the suitable medium for growing the primary hepatic cells of this species, we compared the condition of cells cultured in three media that are frequently used for mammalian cell culture: Dulbecco's Modified Eagle's Medium, RPMI-1640, and William's E. Of these, William's E medium was best suited for culturing the hepatic cells of this species. Using periodic acid-Schiff staining and ultrastructural observations, we demonstrated the cells collected from mongoose livers were hepatocytes. To evaluate the distribution of mercury (Hg) in the liver tissue, we carried out autometallography staining. Most of the Hg compounds were found in the central region of hepatic lobules. Smooth endoplasmic reticulum, which plays a role inxenobiotic metabolism, lipid/cholesterol metabolism, and the digestion and detoxification of lipophilic substances is grown in this area. This suggested that Hg colocalized with smooth endoplasmic reticulum. The results of the present study could be useful to identify the detoxification systems of wildlife with high Hg content in the body, and to evaluate the susceptibility of wildlife to Hg toxicity. PMID:25142347

  3. Suppression of Hepatic Cyp1a2 by Total Ginsenosides in Lipopolysaccharide-Treated Mice and Primary Mouse Hepatocytes.

    PubMed

    Sun, Haiyan; Yan, Yijing; Xu, Chenshu; Wan, Hongxia; Liu, Dong

    2016-03-23

    The roots of Panax ginseng (ginseng) have been extensively used in traditional Chinese medicine. However, herb-drug interactions between ginseng and other co-administered drugs are not fully understood concerning the effect of ginseng on drug metabolism and clearance. The current study aimed to elucidate the effect of total ginsenosides, a typical ginseng extract, on the regulation of Cyp1a2, a key enzyme to regulate drug metabolism under the normal and inflammatory conditions in mice. Female C57BL/6J mice treated with vehicle and lipopolysaccharide (LPS) were intragastrically administered ginseng extract for 7 days before hepatic P450 expression was analyzed. Primary mouse hepatocytes were also employed to further explore the effects of total ginsenosides on Cyp1a2 expression. The results showed that total ginsenosides in P. ginseng extract exhibited a concentration-dependent suppression on Cyp1a2 mRNA and protein level in both mice and primary mouse hepatocytes. Notably, the inhibitory effects of total ginsenosides on Cyp1a2 mRNA and protein expression were further enhanced following LPS treatment. Therefore, future research is warranted to investigate the role of ginsenosides in the regulation of hepatic CYP450s. Moreover, consumption of ginseng as food or supplement should be monitored for patients on combinational therapy, especially those with inflammatory diseases. PMID:26923348

  4. A Nonhuman Primate Model of Human Radiation-Induced Venocclusive Liver Disease and Hepatocyte Injury

    SciTech Connect

    Yannam, Govardhana Rao; Han, Bing; Setoyama, Kentaro; Yamamoto, Toshiyuki; Ito, Ryotaro; Brooks, Jenna M.; Guzman-Lepe, Jorge; Galambos, Csaba; Fong, Jason V.; Deutsch, Melvin; Quader, Mubina A.; Yamanouchi, Kosho; Kabarriti, Rafi; Mehta, Keyur; Soto-Gutierrez, Alejandro; and others

    2014-02-01

    Background: Human liver has an unusual sensitivity to radiation that limits its use in cancer therapy or in preconditioning for hepatocyte transplantation. Because the characteristic veno-occlusive lesions of radiation-induced liver disease do not occur in rodents, there has been no experimental model to investigate the limits of safe radiation therapy or explore the pathogenesis of hepatic veno-occlusive disease. Methods and Materials: We performed a dose-escalation study in a primate, the cynomolgus monkey, using hypofractionated stereotactic body radiotherapy in 13 animals. Results: At doses ≥40 Gy, animals developed a systemic syndrome resembling human radiation-induced liver disease, consisting of decreased albumin, elevated alkaline phosphatase, loss of appetite, ascites, and normal bilirubin. Higher radiation doses were lethal, causing severe disease that required euthanasia approximately 10 weeks after radiation. Even at lower doses in which radiation-induced liver disease was mild or nonexistent, latent and significant injury to hepatocytes was demonstrated by asialoglycoprotein-mediated functional imaging. These monkeys developed hepatic failure with encephalopathy when they received parenteral nutrition containing high concentrations of glucose. Histologically, livers showed central obstruction via an unusual intimal swelling that progressed to central fibrosis. Conclusions: The cynomolgus monkey, as the first animal model of human veno-occlusive radiation-induced liver disease, provides a resource for characterizing the early changes and pathogenesis of venocclusion, for establishing nonlethal therapeutic dosages, and for examining experimental therapies to minimize radiation injury.

  5. Biguanide-induced mitochondrial dysfunction yields increased lactate production and cytotoxicity of aerobically-poised HepG2 cells and human hepatocytes in vitro

    SciTech Connect

    Dykens, James A. Jamieson, Joseph; Marroquin, Lisa; Nadanaciva, Sashi; Billis, Puja A.; Will, Yvonne

    2008-12-01

    As a class, the biguanides induce lactic acidosis, a hallmark of mitochondrial impairment. To assess potential mitochondrial impairment, we evaluated the effects of metformin, buformin and phenformin on: 1) viability of HepG2 cells grown in galactose, 2) respiration by isolated mitochondria, 3) metabolic poise of HepG2 and primary human hepatocytes, 4) activities of immunocaptured respiratory complexes, and 5) mitochondrial membrane potential and redox status in primary human hepatocytes. Phenformin was the most cytotoxic of the three with buformin showing moderate toxicity, and metformin toxicity only at mM concentrations. Importantly, HepG2 cells grown in galactose are markedly more susceptible to biguanide toxicity compared to cells grown in glucose, indicating mitochondrial toxicity as a primary mode of action. The same rank order of potency was observed for isolated mitochondrial respiration where preincubation (40 min) exacerbated respiratory impairment, and was required to reveal inhibition by metformin, suggesting intramitochondrial bio-accumulation. Metabolic profiling of intact cells corroborated respiratory inhibition, but also revealed compensatory increases in lactate production from accelerated glycolysis. High (mM) concentrations of the drugs were needed to inhibit immunocaptured respiratory complexes, supporting the contention that bioaccumulation is involved. The same rank order was found when monitoring mitochondrial membrane potential, ROS production, and glutathione levels in primary human hepatocytes. In toto, these data indicate that biguanide-induced lactic acidosis can be attributed to acceleration of glycolysis in response to mitochondrial impairment. Indeed, the desired clinical outcome, viz., decreased blood glucose, could be due to increased glucose uptake and glycolytic flux in response to drug-induced mitochondrial dysfunction.

  6. Coactivator PGC-1{alpha} regulates the fasting inducible xenobiotic-metabolizing enzyme CYP2A5 in mouse primary hepatocytes

    SciTech Connect

    Arpiainen, Satu; Jaervenpaeae, Sanna-Mari; Manninen, Aki; Viitala, Pirkko; Lang, Matti A.; Pelkonen, Olavi; Hakkola, Jukka

    2008-10-01

    The nutritional state of organisms and energy balance related diseases such as diabetes regulate the metabolism of xenobiotics such as drugs, toxins and carcinogens. However, the mechanisms behind this regulation are mostly unknown. The xenobiotic-metabolizing cytochrome P450 (CYP) 2A5 enzyme has been shown to be induced by fasting and by glucagon and cyclic AMP (cAMP), which mediate numerous fasting responses. Peroxisome proliferator-activated receptor {gamma} coactivator (PGC)-1{alpha} triggers many of the important hepatic fasting effects in response to elevated cAMP levels. In the present study, we were able to show that cAMP causes a coordinated induction of PGC-1{alpha} and CYP2A5 mRNAs in murine primary hepatocytes. Furthermore, the elevation of the PGC-1{alpha} expression level by adenovirus mediated gene transfer increased CYP2A5 transcription. Co-transfection of Cyp2a5 5' promoter constructs with the PGC-1{alpha} expression vector demonstrated that PGC-1{alpha} is able to activate Cyp2a5 transcription through the hepatocyte nuclear factor (HNF)-4{alpha} response element in the proximal promoter of the Cyp2a5 gene. Chromatin immunoprecipitation assays showed that PGC-1{alpha} binds, together with HNF-4{alpha}, to the same region at the Cyp2a5 proximal promoter. In conclusion, PGC-1{alpha} mediates the expression of CYP2A5 induced by cAMP in mouse hepatocytes through coactivation of transcription factor HNF-4{alpha}. This strongly suggests that PGC-1{alpha} is the major factor mediating the fasting response of CYP2A5.

  7. Noninvasively measuring respiratory activity of rat primary hepatocyte spheroids by scanning electrochemical microscopy.

    PubMed

    Takahashi, Ryosuke; Zhou, Yuanshu; Horiguchi, Yoshiko; Shiku, Hitoshi; Sonoda, Hiroshi; Itabashi, Naoshi; Yamamoto, Jiro; Saito, Taku; Matsue, Tomokazu; Hisada, Akiko

    2014-01-01

    Construction of an in vitro drug screening method for evaluating drug metabolism and toxicity by using cells is required instead of the conventional in vivo one that uses animals. In order to realize the in vitro study, analyzing the cellular activity or viability noninvasively in advance of the screening is essential. The aim of the current study is to establish a method that can evaluate the cellular activity depending on spheroid sizes by means of oxygen consumption and to determine the valid diameter of hepatocyte spheroids. To measure the respiratory activity of the spheroids, which were formed on a nanopillar sheet, we applied scanning electrochemical microscopy (SECM). From the viewpoint of high respiratory activity and its small variation, we determined that spheroids with 70 μm in diameter were adequate. We then performed a gene expression analysis by using a real-time PCR to evaluate the correlation with respiratory activity. As a result, a higher expression level of Hnf4α, which is essential for hepatocytes to fulfill many liver functions and is the indicator of well-differentiated hepatocytes, showed relatively higher respiratory activity. We concluded that the noninvasive SECM technique could evaluate the cellular activity of a single spheroid. Noninvasively measuring cellular activity by SECM makes it possible to evaluate the cellular activity prior to a nonclinical test and enables the continued monitoring of the drug response by using single spheroid. SECM becomes a powerful tool to satisfying the increasing demand for an in vitro system in the course of new drug development. PMID:23890543

  8. Rifampin Regulation of Drug Transporters Gene Expression and the Association of MicroRNAs in Human Hepatocytes

    PubMed Central

    Benson, Eric A.; Eadon, Michael T.; Desta, Zeruesenay; Liu, Yunlong; Lin, Hai; Burgess, Kimberly S.; Segar, Matthew W.; Gaedigk, Andrea; Skaar, Todd C.

    2016-01-01

    Membrane drug transporters contribute to the disposition of many drugs. In human liver, drug transport is controlled by two main superfamilies of transporters, the solute carrier transporters (SLC) and the ATP Binding Cassette transporters (ABC). Altered expression of these transporters due to drug-drug interactions can contribute to differences in drug exposure and possibly effect. In this study, we determined the effect of rifampin on gene expression of hundreds of membrane transporters along with all clinically relevant drug transporters. Methods: In this study, primary human hepatocytes (n = 7 donors) were cultured and treated for 24 h with rifampin and vehicle control. RNA was isolated from the hepatocytes, mRNA expression was measured by RNA-seq, and miRNA expression was analyzed by Taqman OpenArray. The effect of rifampin on the expression of selected transporters was also tested in kidney cell lines. The impact of rifampin on the expression of 410 transporter genes from 19 different transporter gene families was compared with vehicle control. Results: Expression patterns of 12 clinically relevant drug transporter genes were changed by rifampin (FDR < 0.05). For example, the expressions of ABCC2, ABCB1, and ABCC3 were increased 1.9-, 1.7-, and 1.2-fold, respectively. The effects of rifampin on four uptake drug transporters (SLCO1B3, SLC47A1, SLC29A1, SLC22A9) were negatively correlated with the rifampin effects on specific microRNA expression (SLCO1B3/miR-92a, SLC47A1/miR-95, SLC29A1/miR-30d#, and SLC22A9/miR-20; r < −0.79; p < 0.05). Seven hepatic drug transporter genes (SLC22A1, SLC22A5, SLC15A1, SLC29A1, SLCO4C1, ABCC2, and ABCC4), whose expression was altered by rifampin in hepatocytes, were also present in a renal proximal tubular cell line, but in renal cells rifampin did not alter their gene expression. PXR expression was very low in the kidney cells; this may explain why rifampin induces gene expression in a tissue-specific manner. Conclusion

  9. BST-2 expression in human hepatocytes is inducible by all three types of interferons and restricts production of hepatitis C virus.

    PubMed

    Amet, T; Byrd, D; Hu, N; Sun, Q; Li, F; Zhao, Y; Hu, S; Grantham, A; Yu, Q

    2014-03-01

    Bone marrow stromal cell antigen 2 (BST-2, also known as tetherin, CD317, or HM1.24) has recently been identified as a host restriction factor against diverse families of enveloped viruses. However, the effects of BST-2 on the life cycle of hepatitis C virus (HCV), an enveloped RNA virus, remain unclear and controversial. Here we demonstrated that human hepatocytes including Huh7.5.1 cells, primary human hepatocytes (PHHs), and HepG2 cells constitutively expressed low to moderate levels of endogenous BST-2 on the cell surface, which could be robustly up-regulated by all three types of interferons (IFNs) such as IFN-α, IFN-γ, and IFN-λ. IFN-α and IFN-γ showed a synergistic effect in induction of BST-2 expression on human hepatocytes. Over-expression of BST-2 by BST-2-expressing vector transfection or up-regulation of BST-2 by IFN stimulation markedly suppressed HCV production, whereas shRNA-mediated depletion of endogenous BST-2 significantly enhanced HCV production in infected Huh7.5.1 cells. IFN-mediated anti-HCV activity was partially but significantly diminished by shRNA-mediated knockdown of BST-2 expression, indicating that BST- 2 upregulation is directly involved in IFN-mediated inhibition of HCV production. We also found that both BST-2 and HCV core co-localized with intracellular lipid droplets (LDs), suggesting that BST-2-HCV interaction may take place around LDs as LDs constitute an important intracellular organelle for HCV assembly and replication. Taken together, our data suggest that BST-2 is a host restriction factor against HCV, and induction of BST-2 in hepatocytes could be one of the mechanisms by which current HCV standard therapy (IFN-α plus ribavirin) achieves a sustained virological response (SVR). PMID:24236455

  10. Water-Stable Metal-Organic Framework/Polymer Composites Compatible with Human Hepatocytes.

    PubMed

    Neufeld, Megan J; Ware, Brenton R; Lutzke, Alec; Khetani, Salman R; Reynolds, Melissa M

    2016-08-01

    Metal-organic frameworks (MOFs) have demonstrated promise in biomedical applications as vehicles for drug delivery, as well as for the ability of copper-based MOFs to generate nitric oxide (NO) from endogenous S-nitrosothiols (RSNOs). Because NO is a participant in biological processes where it exhibits anti-inflammatory, antibacterial, and antiplatelet activation properties, it has received significant attention for therapeutic purposes. Previous work has shown that the water-stable MOF H3[(Cu4Cl)3-(BTTri)8] (H3BTTri = 1,3,5-tris(1H-1,2,3-triazol-5-yl)benzene), or CuBTTri, produces NO from RSNOs and can be included within a polymeric matrix to form NO-generating materials. While such materials demonstrate potential, the possibility of MOF degradation leading to copper-related toxicity is a concern that must be addressed prior to adapting these materials for biomedical applications. Herein, we present the first cytotoxicity evaluation of an NO-generating CuBTTri/polymer composite material using 3T3-J2 murine embryonic fibroblasts and primary human hepatocytes (PHHs). CuBTTri/polymer films were prepared from plasticized poly(vinyl chloride) (PVC) and characterized via PXRD, ATR-FTIR, and SEM-EDX. Additionally, the ability of the CuBTTri/polymer films to enhance NO generation from S-nitroso-N-acetylpenicillamine (SNAP) was evaluated. Enhanced NO generation in the presence of the CuBTTri/polymer films was observed, with an average NO flux (0.90 ± 0.13 nmol cm(-2) min(-1)) within the range associated with antithrombogenic surfaces. The CuBTTri/polymer films were analyzed for stability in phosphate buffered saline (PBS) and cell culture media under physiological conditions for a 4 week duration. Cumulative copper release in both cell media (0.84 ± 0.21%) and PBS (0.18 ± 0.01%) accounted for less than 1% of theoretical copper present in the films. In vitro cell studies performed with 3T3-J2 fibroblasts and PHHs did not indicate significant toxicity, providing further

  11. Isolated rat hepatocyte couplets: a primary secretory unit for electrophysiologic studies of bile secretory function.

    PubMed

    Graf, J; Gautam, A; Boyer, J L

    1984-10-01

    Hepatocyte couplets were isolated by collagenase perfusion from rat liver. Between adjacent cells, the bile canaliculus forms a closed space into which secretion occurs. As in intact liver, Mg2+-ATPase is localized at the canalicular lumen, the organic anion fluorescein is excreted, and secretion is modified by osmotic gradients. By passing a microelectrode through one cell into the canalicular vacuole, a transepithelial potential profile was obtained. In 27 cell couplets the steady-state intracellular (-26.3 +/- 5.3 mV) and intracanalicular (-5.9 +/- 3.3 mV) potentials were recorded at 37 degrees C with reference to the external medium. Input resistances were determined within the cell (86 +/- 23 M omega) and in the bile canalicular lumen (32 +/- 17 M omega) by passing current pulses through the microelectrode. These data define electrical driving forces for ion transport across the sinusoidal, canalicular, and paracellular barriers and indicate ion permeation across a leaky paracellular junctional pathway. These findings indicate that the isolated hepatocyte couplet is an effective model for electrophysiologic studies of bile secretory function. PMID:6149546

  12. Physiological oxygen tensions modulate expression of the mdr1b multidrug-resistance gene in primary rat hepatocyte cultures.

    PubMed Central

    Hirsch-Ernst, K I; Kietzmann, T; Ziemann, C; Jungermann, K; Kahl, G F

    2000-01-01

    P-Glycoprotein transporters encoded by mdr1 (multidrug resistance) genes mediate extrusion of an array of lipophilic xenobiotics from the cell. In rat liver, mdr transcripts have been shown to be expressed mainly in hepatocytes of the periportal region. Since gradients in oxygen tension (pO(2)) may contribute towards zonated gene expression, the influence of arterial and venous pO(2) on mRNA expression of the mdr1b isoform was examined in primary rat hepatocytes cultured for up to 3 days. Maximal mdr1b mRNA levels (100%) were observed under arterial pO(2) after 72 h, whereas less than half-maximal mRNA levels (40%) were attained under venous pO(2). Accordingly, expression of mdr protein and extrusion of the mdr1 substrate rhodamine 123 were maximal under arterial pO(2) and reduced under venous pO(2). Oxygen-dependent modulation of mdr1b mRNA expression was prevented by actinomycin D, indicating transcriptional regulation. Inhibition of haem synthesis by 25 microM CoCl(2) blocked mdr1b mRNA expression under both oxygen tensions, whereas 80 microM desferrioxamine abolished modulation by O(2). Haem (10 microM) increased mdr1b mRNA levels under arterial and venous pO(2). In hepatocytes treated with 50 microM H(2)O(2), mdr1b mRNA expression was elevated by about 1.6-fold at venous pO(2) and 1.5-fold at arterial pO(2). These results support the conclusion that haem proteins are crucial for modulation of mdr1b mRNA expression by O(2) in hepatocyte cultures and that reactive oxygen species may participate in O(2)-dependent signal transduction. Furthermore, the present study suggests that oxygen might be a critical modulator for zonated secretion of mdr1 substrates into the bile. PMID:10947958

  13. Drug metabolism by cultured human hepatocytes: how far are we from the in vivo reality?

    PubMed

    Ponsoda, Xavier; Donato, M Teresa; Perez-Cataldo, Gabriela; Gómez-Lechón, Maria José; Castell, José V

    2004-06-01

    The investigation of metabolism is an important milestone in the course of drug development. Drug metabolism is a determinant of drug pharmacokinetics variability in human beings. Fundamental to this are phenotypic differences, as well as genotypic differences, in the expression of the enzymes involved in drug metabolism. Genotypic variability is easy to identify by means of polymerase chain reaction-based or DNA chip-based methods, whereas phenotypic variability requires direct measurement of enzyme activities in liver, or, indirectly, measurement of the rate of metabolism of a given compound in vivo. There is a great deal of phenotypic variability in human beings, only a minor part being attributable to gene polymorphisms. Thus, enzyme activity measurements in a series of human livers, as well as in vivo studies with human volunteers, show that phenotypic variability is, by far, much greater than genotypic variability. In vitro models are currently used to investigate the hepatic metabolism of new compounds. Cultured human hepatocytes are considered to be the closest model to the human liver. However, the fact that hepatocytes are placed in a microenvironment that differs from that of the cells in the liver raises the question of to what extent drug metabolism variability observed in vitro actually reflects that in the liver in vivo. This issue has been examined by investigating the metabolism of the model compound, aceclofenac (an approved analgesic/anti-inflammatory drug), both in vitro and in vivo. Hepatocytes isolated from programmed liver biopsies were incubated with aceclofenac, and the metabolites formed were investigated by HPLC. The patients were given the drug during the course of clinical recovery, and the metabolites, largely present in urine, were analysed. In vitro and in vivo data from the same individual were compared. There was a good correlation between the in vitro and in vivo relative abundance of oxidised metabolites (4'-OH-aceclofenac + 4

  14. Suppression of CYP2B Induction by Alendronate-Mediated Farnesyl Diphosphate Synthase Inhibition in Primary Cultured Rat Hepatocytes

    PubMed Central

    Jackson, Nancy M.; Kocarek, Thomas A.

    2008-01-01

    We previously reported that squalestatin 1-mediated induction of CYP2B expression is attributable to squalene synthase inhibition and accumulation of an endogenous isoprenoid(s) that is capable of activating the constitutive androstane receptor. To determine whether squalestatin 1-mediated CYP2B induction is strictly dependent upon the biosynthesis of farnesyl pyrophosphate (FPP), the substrate for squalene synthase, the effects of alendronate, a nitrogen-containing bisphosphonate inhibitor of farnesyl diphosphate synthase, were determined on basal, squalestatin 1-inducible, and phenobarbital-inducible CYP2B expression in primary cultured rat hepatocytes. Alendronate treatment alone had no effect on CYP2B or CYP3A mRNA expression in the hepatocyte cultures, but alendronate co-treatment completely suppressed squalestatin 1-mediated CYP2B mRNA induction at concentrations (60 and 100 μM) that effectively inhibited cellular farnesyl diphosphate synthase activity, as assessed by reductions of squalestatin 1-mediated FPP accumulation, and that were not toxic to the cells, as indicated by a lack of effect on MTT activity. Alendronate co-treatment also partially suppressed phenobarbital-inducible CYP2B expression, and this suppressive effect was attenuated by additional co-treatment with the upstream pathway inhibitor, pravastatin. These findings demonstrate that squalestatin 1-mediated CYP2B induction cannot occur in the absence of FPP biosynthesis, but also indicate that one or more upstream isoprenoids, possibly isopentenyl pyrophosphate and/or dimethylallyl pyrophosphate, function to antagonize the CYP2B induction process. PMID:18617600

  15. Suppression in PHLPP2 induction by morin promotes Nrf2-regulated cellular defenses against oxidative injury to primary rat hepatocytes

    PubMed Central

    Rizvi, Fatima; Mathur, Alpana; Krishna, Shagun; Siddiqi, Mohammad Imran; Kakkar, Poonam

    2015-01-01

    Recent advances indicate a possible role of phytochemicals as modulatory factors in signaling pathways. We have previously demonstrated PHLPP2-mediated suppression of Nrf2 responses during oxidant attack. The present study was designed to explore Nrf2-potentiating mechanism of morin, a flavonol, via its possible role in intervening PHLPP2-regulated Akt/GSK3β/Fyn kinase axis. Efficacy of morin was evaluated against oxidative stress-mediated damage to primary hepatocytes by tert-butyl hydroperoxide (tBHP) and acetaminophen. The anti-cytotoxic effects of morin were found to be a consequence of fortification of Nrf2-regulated antioxidant defenses since morin failed to sustain activities of redox enzyme in Nrf2 silenced hepatocytes. Morin promoted Nrf2 stability and its nuclear retention by possibly modulating PHLPP2 activity which subdues cellular Nrf2 responses by activating Fyn kinase. Pull-down assay using morin-conjugated beads indicated the binding affinity of morin towards PHLPP2. Molecular docking also revealed the propensity of morin to occupy the active site of PHLPP2 enzyme. Thus, dietary phytochemical morin was observed to counteract oxidant-induced hepatocellular damage by promoting Nrf2-regulated transcriptional induction. The findings support the novel role of morin in potentiating Nrf2 responses by limiting PHLPP2 and hence Fyn kinase activation. Therefore, morin may be exploited in developing novel therapeutic strategy aimed at enhancing Nrf2 responses. PMID:26513344

  16. In vitro assay for drug-induced hepatosteatosis using rat primary hepatocytes, a fluorescent lipid analog and gene expression analysis.

    PubMed

    Fujimura, Hisako; Murakami, Naoko; Kurabe, Michie; Toriumi, Wataru

    2009-05-01

    To evaluate new drugs' potential for hepatosteatosis, we developed a cell-based assay using a fluorescent fatty acid analog: BODIPY558/568 C12. Rat primary hepatocytes were exposed to positive reference compounds [cyclosporine A (CsA), clofibrate (CFR), tetracycline (TC), valproic acid (VPA), carbon tetrachloride (CCl4), tamoxifen (TMX)] in the presence of BODIPY558/568 C12. The formation of fluorscecent particles or lipid droplets in the cytoplasm was confirmed by confocal laser scanning microscopy and electron microscopy respectively. The accumulation of BODIPY558/568 C12 was measured by fluorometry and high content imaging method. All positive reference compounds increased fluorescent particles in number and fluorescence intensity. High content imaging was more sensitive and selective method than fluorometry to detect fluorescent particles. Gene expression analysis of the hepatocytes showed two patterns: genes related to lipid metabolism/synthesis were down-regulated by oxidative stress inducing compounds: CsA, TC and TMX, and up-regulated by peroxisome proliferator-activated receptor-alpha agonists: CFR and VPA. From these findings, we concluded that the cell-based assay developed in this study is an appropriate method to predict drugs' potential for hepatosteatosis, and gene expression analysis is useful to profile the mechanism of the hepatosteatosis. PMID:19224547

  17. Expression of two CYP1A genes in {beta}NF and TCDD-treated rainbow trout primary hepatocyte culture

    SciTech Connect

    Rabergh, C.M.; Lipsky, M.M.; Vroliijk, N.H.; Chen, T.T.

    1995-12-31

    In mammalian systems, it is well known that two CYP1A genes are expressed in response to environmental toxicants such as polycyclic aromatic hydrocarbons (PAHs) and TCDD (2,3,7,3-tetrachlorodibenzo-p-dioxin). The presence of two CYP1A genes in fish has been previously reported, though expression of these two genes has not been characterized. In this study, the authors examined the expression of these two genes in primary culture of rainbow trout hepatocytes treated with {beta}NF and TCDD. Hepatocytes were isolated by a modified two-step collagenase perfusion of the liver and cultured on polylysine coated dishes. The optimum time and concentration of induction was determined for both chemicals. The expression of the genes was also studied in long-term cultures up to 20 days. RNA was isolated by the method of Chomzynski and Sacchi and the RNase protection assay was used to detect the expression of the CYP1A genes by using antisense riboprobes specific for the MRNA of each gene. A differential concentration- and time-dependent expression of the two genes was observed in cells treated with {beta}NF and TCDD. Whether these two genes are paralogous, i.e., produced by gene duplication within the species, or whether one of them may in fact be an orthologue to a mammalian counterpart within the CYP1A family, remains to be determined.

  18. Comparison of human hepatoma HepaRG cells with human and rat hepatocytes in uptake transport assays in order to predict a risk of drug induced hepatotoxicity.

    PubMed

    Szabo, Monika; Veres, Zsuzsa; Baranyai, Zsolt; Jakab, Ferenc; Jemnitz, Katalin

    2013-01-01

    Human hepatocytes are the gold standard for toxicological studies but they have several drawbacks, like scarce availability, high inter-individual variability, a short lifetime, which limits their applicability. The aim of our investigations was to determine, whether HepaRG cells could replace human hepatocytes in uptake experiments for toxicity studies. HepaRG is a hepatoma cell line with most hepatic functions, including a considerable expression of uptake transporters in contrast to other hepatic immortalized cell lines. We compared the effect of cholestatic drugs (bosentan, cyclosporinA, troglitazone,) and bromosulfophthalein on the uptake of taurocholate and estrone-3-sulfate in human and rat hepatocytes and HepaRG cells. The substrate uptake was significantly slower in HepaRG cells than in human hepatocytes, still, in the presence of drugs we observed a concentration dependent decrease in uptake. In all cell types, the culture time had a significant impact not only on the uptake process but on the inhibitory effect of drugs too. The most significant drug effect was measured at 4 h after seeding. Our report is among the first concerning interactions of the uptake transporters in the HepaRG, at the functional level. Results of the present study clearly show that concerning the inhibition of taurocholate uptake by cholestatic drugs, HepaRG cells are closer to human hepatocytes than rat hepatocytes. In conclusion, we demonstrated that HepaRG cells may provide a suitable tool for hepatic uptake studies. PMID:23516635

  19. Human Hepatocyte-Derived Induced Pluripotent Stem Cells: MYC Expression, Similarities to Human Germ Cell Tumors, and Safety Issues

    PubMed Central

    Unzu, Carmen; Friedli, Marc; Bosman, Alexis; Jaconi, Marisa E.; Wildhaber, Barbara E.; Rougemont, Anne-Laure

    2016-01-01

    Induced pluripotent stem cells (iPSC) are a most promising approach to the development of a hepatocyte transplantable mass sufficient to induce long-term correction of inherited liver metabolic diseases, thus avoiding liver transplantation. Their intrinsic self-renewal ability and potential to differentiate into any of the three germ layers identify iPSC as the most promising cell-based therapeutics, but also as drivers of tumor development. Teratoma development currently represents the gold standard to assess iPSC pluripotency. We analyzed the tumorigenic potential of iPSC generated from human hepatocytes (HEP-iPSC) and compared their immunohistochemical profiles to that of tumors developed from fibroblast and hematopoietic stem cell-derived iPSC. HEP-iPSC generated tumors significantly presented more malignant morphological features than reprogrammed fibroblasts or CD34+ iPSC. Moreover, the protooncogene myc showed the strongest expression in HEP-iPSC, compared to only faint expression in the other cell subsets. Random integration of transgenes and the use of potent protooncogenes such as myc might be a risk factor for malignant tumor development if hepatocytes are used for reprogramming. Nonviral vector delivery systems or reprogramming of cells obtained from less invasive harvesting methods would represent interesting options for future developments in stem cell-based approaches for liver metabolic diseases. PMID:26880963

  20. Amelioration of Hyperbilirubinemia in Gunn Rats after Transplantation of Human Induced Pluripotent Stem Cell-Derived Hepatocytes

    PubMed Central

    Chen, Yong; Li, Yanfeng; Wang, Xia; Zhang, Wei; Sauer, Vanessa; Chang, Chan-Jung; Han, Bing; Tchaikovskaya, Tatyana; Avsar, Yesim; Tafaleng, Edgar; Madhusudana Girija, Sanal; Tar, Krisztina; Polgar, Zsuzsanna; Strom, Stephen; Bouhassira, Eric E.; Guha, Chandan; Fox, Ira J.; Roy-Chowdhury, Jayanta; Roy-Chowdhury, Namita

    2015-01-01

    Summary Hepatocyte transplantation has the potential to cure inherited liver diseases, but its application is impeded by a scarcity of donor livers. Therefore, we explored whether transplantation of hepatocyte-like cells (iHeps) differentiated from human induced pluripotent stem cells (iPSCs) could ameliorate inherited liver diseases. iPSCs reprogrammed from human skin fibroblasts were differentiated to iHeps, which were transplanted into livers of uridinediphosphoglucuronate glucuronosyltransferase-1 (UGT1A1)-deficient Gunn rats, a model of Crigler-Najjar syndrome 1 (CN1), where elevated unconjugated bilirubin causes brain injury and death. To promote iHep proliferation, 30% of the recipient liver was X-irradiated before transplantation, and hepatocyte growth factor was expressed. After transplantation, UGT1A1+ iHep clusters constituted 2.5%–7.5% of the preconditioned liver lobe. A decline of serum bilirubin by 30%–60% and biliary excretion of bilirubin glucuronides indicated that transplanted iHeps expressed UGT1A1 activity, a postnatal function of hepatocytes. Therefore, iHeps warrant further exploration as a renewable source of hepatocytes for treating inherited liver diseases. PMID:26074313

  1. Small-Molecule-Directed Hepatocyte-Like Cell Differentiation of Human Pluripotent Stem Cells.

    PubMed

    Mathapati, Santosh; Siller, Richard; Impellizzeri, Agata A R; Lycke, Max; Vegheim, Karianne; Almaas, Runar; Sullivan, Gareth J

    2016-01-01

    Hepatocyte-like cells (HLCs) generated in vitro from human pluripotent stem cells (hPSCs) provide an invaluable resource for basic research, regenerative medicine, drug screening, toxicology, and modeling of liver disease and development. This unit describes a small-molecule-driven protocol for in vitro differentiation of hPSCs into HLCs without the use of growth factors. hPSCs are coaxed through a developmentally relevant route via the primitive streak to definitive endoderm (DE) using the small molecule CHIR99021 (a Wnt agonist), replacing the conventional growth factors Wnt3A and activin A. The small-molecule-derived DE is then differentiated to hepatoblast-like cells in the presence of dimethyl sulfoxide. The resulting hepatoblasts are then differentiated to HLCs with N-hexanoic-Tyr, Ile-6 aminohexanoic amide (Dihexa, a hepatocyte growth factor agonist) and dexamethasone. The protocol provides an efficient and reproducible procedure for differentiation of hPSCs into HLCs utilizing small molecules. © 2016 by John Wiley & Sons, Inc. PMID:27532814

  2. PPAR{alpha} regulates the hepatotoxic biomarker alanine aminotransferase (ALT1) gene expression in human hepatocytes

    SciTech Connect

    Thulin, Petra; Rafter, Ingalill; Stockling, Kenneth; Tomkiewicz, Celine; Norjavaara, Ensio; Aggerbeck, Martine; Hellmold, Heike; Ehrenborg, Ewa; Andersson, Ulf; Cotgreave, Ian; Glinghammar, Bjoern

    2008-08-15

    In this work, we investigated a potential mechanism behind the observation of increased aminotransferase levels in a phase I clinical trial using a lipid-lowering drug, the peroxisome proliferator-activated receptor (PPAR) {alpha} agonist, AZD4619. In healthy volunteers treated with AZD4619, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were elevated without an increase in other markers for liver injury. These increases in serum aminotransferases have previously been reported in some patients receiving another PPAR{alpha} agonist, fenofibrate. In subsequent in vitro studies, we observed increased expression of ALT1 protein and mRNA in human hepatocytes after treatment with fenofibric acid. The PPAR effect on ALT1 expression was shown to act through a direct transcriptional mechanism involving at least one PPAR response element (PPRE) in the proximal ALT1 promoter, while no effect of fenofibrate and AZD4619 was observed on the ALT2 promoter. Binding of PPARs to the PPRE located at - 574 bp from the transcriptional start site was confirmed on both synthetic oligonucleotides and DNA in hepatocytes. These data show that intracellular ALT expression is regulated by PPAR agonists and that this mechanism might contribute to increased ALT activity in serum.

  3. Drug-induced cholestasis risk assessment in sandwich-cultured human hepatocytes.

    PubMed

    Oorts, Marlies; Baze, Audrey; Bachellier, Philippe; Heyd, Bruno; Zacharias, Thomas; Annaert, Pieter; Richert, Lysiane

    2016-08-01

    Drug-induced cholestasis (DIC) is recognized as one of the prime mechanisms for DILI. Hence, earlier detection of drug candidates with cholestatic signature is crucial. Recently, we introduced an in vitro model for DIC and evaluated its performance with several cholestatic drugs. We presently expand on the validation of this model by 14 training compounds (TCs) of the EU-EFPIA IMI project MIP-DILI. Several batches of human hepatocytes in sandwich-culture were qualified for DIC assessment by verifying the bile acid-dependent increase in sensitivity to the toxic effects of cyclosporin A. The cholestatic potential of the TCs was expressed by determining the drug-induced cholestasis index (DICI). A safety margin (SM) was calculated as the ratio of the lowest TC concentration with a DICI≤0.80 to the Cmax,total. Nefazodone, bosentan, perhexiline and troglitazone were flagged for cholestasis (SM<30). The hepatotoxic (but non-cholestatic) compounds, amiodarone, diclofenac, fialuridine and ximelagatran, and all non-hepatotoxic compounds were cleared as "safe" for DIC. Tolcapone and paracetamol yielded DICI-based SM values equal to or higher than those based on cytotoxicity, thus excluding DIC as a DILI mechanism. This hepatocyte-based in vitro assay provides a unique tool for early and reliable identification of drug candidates with cholestasis risk. PMID:27046439

  4. Human Hepatocyte Growth Factor Promotes Functional Recovery in Primates after Spinal Cord Injury

    PubMed Central

    Kitamura, Kazuya; Fujiyoshi, Kanehiro; Yamane, Jun-ichi; Toyota, Fumika; Hikishima, Keigo; Nomura, Tatsuji; Funakoshi, Hiroshi; Nakamura, Toshikazu; Aoki, Masashi; Toyama, Yoshiaki; Okano, Hideyuki; Nakamura, Masaya

    2011-01-01

    Many therapeutic interventions for spinal cord injury (SCI) using neurotrophic factors have focused on reducing the area damaged by secondary, post-injury degeneration, to promote functional recovery. Hepatocyte growth factor (HGF), which is a potent mitogen for mature hepatocytes and a mediator of the inflammatory responses to tissue injury, was recently highlighted as a potent neurotrophic factor in the central nervous system. We previously reported that introducing exogenous HGF into the injured rodent spinal cord using a herpes simplex virus-1 vector significantly reduces the area of damaged tissue and promotes functional recovery. However, that study did not examine the therapeutic effects of administering HGF after injury, which is the most critical issue for clinical application. To translate this strategy to human treatment, we induced a contusive cervical SCI in the common marmoset, a primate, and then administered recombinant human HGF (rhHGF) intrathecally. Motor function was assessed using an original open field scoring system focusing on manual function, including reach-and-grasp performance and hand placement in walking. The intrathecal rhHGF preserved the corticospinal fibers and myelinated areas, thereby promoting functional recovery. In vivo magnetic resonance imaging showed significant preservation of the intact spinal cord parenchyma. rhHGF-treatment did not give rise to an abnormal outgrowth of calcitonin gene related peptide positive fibers compared to the control group, indicating that this treatment did not induce or exacerbate allodynia. This is the first study to report the efficacy of rhHGF for treating SCI in non-human primates. In addition, this is the first presentation of a novel scale for assessing neurological motor performance in non-human primates after contusive cervical SCI. PMID:22140459

  5. Activation of the constitutive androstane receptor inhibits gluconeogenesis without affecting lipogenesis or fatty acid synthesis in human hepatocytes

    SciTech Connect

    Lynch, Caitlin; Pan, Yongmei; Li, Linhao; Heyward, Scott; Moeller, Timothy; Swaan, Peter W.; Wang, Hongbing

    2014-08-15

    Objective: Accumulating evidence suggests that activation of mouse constitutive androstane receptor (mCAR) alleviates type 2 diabetes and obesity by inhibiting hepatic gluconeogenesis, lipogenesis, and fatty acid synthesis. However, the role of human (h) CAR in energy metabolism is largely unknown. The present study aims to investigate the effects of selective hCAR activators on hepatic energy metabolism in human primary hepatocytes (HPH). Methods: Ligand-based structure–activity models were used for virtual screening of the Specs database ( (www.specs.net)) followed by biological validation in cell-based luciferase assays. The effects of two novel hCAR activators (UM104 and UM145) on hepatic energy metabolism were evaluated in HPH. Results: Real-time PCR and Western blotting analyses reveal that activation of hCAR by UM104 and UM145 significantly repressed the expression of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, two pivotal gluconeogenic enzymes, while exerting negligible effects on the expression of genes associated with lipogenesis and fatty acid synthesis. Functional experiments show that UM104 and UM145 markedly inhibit hepatic synthesis of glucose but not triglycerides in HPH. In contrast, activation of mCAR by 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene, a selective mCAR activator, repressed the expression of genes associated with gluconeogenesis, lipogenesis, and fatty acid synthesis in mouse primary hepatocytes, which were consistent with previous observations in mouse model in vivo. Conclusion: Our findings uncover an important species difference between hCAR and mCAR in hepatic energy metabolism, where hCAR selectively inhibits gluconeogenesis without suppressing fatty acid synthesis. Implications: Such species selectivity should be considered when exploring CAR as a potential therapeutic target for metabolic disorders. - Highlights: • Novel hCAR activators were identified by computational and biological approaches. • The role

  6. Human and rat hepatocyte toxicity and protein phosphatase 1 and 2A inhibitory activity of naturally occurring desmethyl-microcystins and nodularins.

    PubMed

    Ufelmann, Helena; Krüger, Thomas; Luckas, Bernd; Schrenk, Dieter

    2012-03-11

    Contamination of water, foods and food supplements by various genera of cyanobacteria is a serious health problem worldwide for humans and animals, largely due to the toxic effects of microcystins (MCs) and nodularin (NOD), a group of hepatotoxic cyclic peptides. The toxins occur in variable structures resulting in more than 90 different MCs and 8 different NODs, many of them not having been investigated for their toxic potency. Potent MCs such as MC-LR have been shown to elicit their hepatotoxic potency via inhibition of hepatic protein phosphatases (PP) 1 and 2A leading to over-phosphorylation of vital cellular proteins. This mechanism of action is also thought to be responsible for the long term tumor promoting action of certain MCs and NOD in the liver. Here, we report on the isolation of certain MCs and NOD as well as a number of their desmethylated derivatives from algae bloom. Subsequently, we determined the cytotoxicity of these compounds in isolated primary human and rat hepatocytes in culture. In parallel experiments, we analyzed the inhibitory potency of these congeners on PP1 and 2A using commercially available enzymes. We found in primary rat hepatocytes that MC-LR, -YR and NOD were cytotoxic, namely in the 10 to >50 nM range, while MC-RR was not. The desmethylated congeners of MC-LR, -YR, and NOD were equally or more-toxic as/than their fully methylated counterparts. In primary human hepatocytes we could show that MC-LR, NOD and the desmethylated variants [³Asp]MC-LR, [⁷Dha]MC-LR and [¹Asp]NOD were cytotoxic in the 20 to >600 nM range. Inhibition data with human, bovine and rabbit protein phosphatases 1 and 2A were roughly in accordance with the cytotoxicity findings in human and rat hepatocytes, i.e. desmethylation had no pronounced effects on the inhibitory potencies. Thus, a variety of naturally occurring desmethylated MC and NOD congeners have to be considered as being at least as toxic as the corresponding fully methylated derivatives. PMID

  7. Evaluation of Adverse Drug Properties with Cryopreserved Human Hepatocytes and the Integrated Discrete Multiple Organ Co-culture (IdMOCTM) System

    PubMed Central

    2015-01-01

    Human hepatocytes, with complete hepatic metabolizing enzymes, transporters and cofactors, represent the gold standard for in vitro evaluation of drug metabolism, drug-drug interactions, and hepatotoxicity. Successful cryopreservation of human hepatocytes enables this experimental system to be used routinely. The use of human hepatocytes to evaluate two major adverse drug properties: drug-drug interactions and hepatotoxicity, are summarized in this review. The application of human hepatocytes in metabolism-based drug-drug interaction includes metabolite profiling, pathway identification, P450 inhibition, P450 induction, and uptake and efflux transporter inhibition. The application of human hepatocytes in toxicity evaluation includes in vitro hepatotoxicity and metabolism-based drug toxicity determination. A novel system, the Integrated Discrete Multiple Organ Co-culture (IdMOC) which allows the evaluation of nonhepatic toxicity in the presence of hepatic metabolism, is described. PMID:26191380

  8. Comparison of hepatocarcinogen-induced gene expression profiles in conventional primary rat hepatocytes with in vivo rat liver.

    PubMed

    Doktorova, Tatyana Y; Ellinger-Ziegelbauer, Heidrun; Vinken, Mathieu; Vanhaecke, Tamara; van Delft, Joost; Kleinjans, Jos; Ahr, Hans-Juergen; Rogiers, Vera

    2012-09-01

    At present, substantial efforts are focused on the development of in vitro assays coupled with "omics" technologies for the identification of carcinogenic substances as an alternative to the classical 2-year rodent carcinogenicity bioassay. A prerequisite for the eventual regulatory acceptance of such assays, however, is the in vivo relevance of the observed in vitro findings. In the current study, hepatocarcinogen-induced gene expression profiles generated after the exposure of conventional cultures of primary rat hepatocytes to three non-genotoxic carcinogens (methapyrilene hydrochloride, piperonyl butoxide, and Wy-14643), three genotoxic carcinogens (aflatoxin B1, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and 2-nitrofluorene), and two non-carcinogens (nifedipine and clonidine) are compared with previously obtained in vivo data after oral administration for up to 14 days of the same hepatocarcinogens to rats. In addition to the comparison of deregulated genes and functions per compound between in vivo and in vitro models, the major discriminating cellular pathways found in vivo in livers of exposed rats were examined for deregulation in vitro. Further, in vivo-derived gene signatures for the identification of genotoxic versus non-genotoxic carcinogens are used to classify in vitro-tested hepatocarcinogens and non-carcinogens. In the primary hepatocyte cultures, two out of the three tested genotoxic carcinogens mimicked the in vivo-relevant DNA damage response and were correctly assessed. Exposure to the non-genotoxic hepatocarcinogens, however, triggered a relatively weak response in the in vitro system, with no clear similarities to in vivo. This study contributes to the further optimization of toxicogenomics predictive tools when applied in in vitro settings. PMID:22484513

  9. O-hexadecyl-dextran entrapped berberine nanoparticles abrogate high glucose stress induced apoptosis in primary rat hepatocytes.

    PubMed

    Kapoor, Radhika; Singh, Shruti; Tripathi, Madhulika; Bhatnagar, Priyanka; Kakkar, Poonam; Gupta, Kailash Chand

    2014-01-01

    Nanotized phytochemicals are being explored by researchers for promoting their uptake and effectiveness at lower concentrations. In this study, O-hexadecyl-dextran entrapped berberine chloride nanoparticles (BC-HDD NPs) were prepared, and evaluated for their cytoprotective efficacy in high glucose stressed primary hepatocytes and the results obtained compared with bulk berberine chloride (BBR) treatment. The nanotized formulation treated primary hepatocytes that were exposed to high glucose (40 mM), showed increased viability compared to the bulk BBR treated cells. BC-HDD NPs reduced the ROS generation by ∼ 3.5 fold during co-treatment, prevented GSH depletion by ∼ 1.6 fold, reduced NO formation by ∼ 5 fold and significantly prevented decline in SOD activity in stressed cells. Lipid peroxidation was also prevented by ∼ 1.9 fold in the presence of these NPs confirming the antioxidant capacity of the formulation. High glucose stress increased Bax/Bcl2 ratio followed by mitochondrial depolarization and activation of caspase-9/-3 confirming involvement of mitochondrial pathway of apoptosis in the exposed cells. Co- and post-treatment of BC-HDD NPs prevented depolarization of mitochondrial membrane, reduced Bax/Bcl2 ratio and prevented externalization of phosphatidyl-serine confirming their anti-apoptotic capacity in those cells. Sub-G1 phase apparent in high glucose stressed cells was not seen in BC-HDD NPs treated cells. The present study reveals that BC-HDD NPs at ∼ 20 fold lower concentration are as effective as BBR in preventing high glucose induced oxidative stress, mitochondrial depolarization and downstream events of apoptotic cell death. PMID:24586539

  10. O-Hexadecyl-Dextran Entrapped Berberine Nanoparticles Abrogate High Glucose Stress Induced Apoptosis in Primary Rat Hepatocytes

    PubMed Central

    Tripathi, Madhulika; Bhatnagar, Priyanka; Kakkar, Poonam; Gupta, Kailash Chand

    2014-01-01

    Nanotized phytochemicals are being explored by researchers for promoting their uptake and effectiveness at lower concentrations. In this study, O-hexadecyl-dextran entrapped berberine chloride nanoparticles (BC-HDD NPs) were prepared, and evaluated for their cytoprotective efficacy in high glucose stressed primary hepatocytes and the results obtained compared with bulk berberine chloride (BBR) treatment. The nanotized formulation treated primary hepatocytes that were exposed to high glucose (40 mM), showed increased viability compared to the bulk BBR treated cells. BC-HDD NPs reduced the ROS generation by ∼3.5 fold during co-treatment, prevented GSH depletion by ∼1.6 fold, reduced NO formation by ∼5 fold and significantly prevented decline in SOD activity in stressed cells. Lipid peroxidation was also prevented by ∼1.9 fold in the presence of these NPs confirming the antioxidant capacity of the formulation. High glucose stress increased Bax/Bcl2 ratio followed by mitochondrial depolarization and activation of caspase-9/−3 confirming involvement of mitochondrial pathway of apoptosis in the exposed cells. Co- and post-treatment of BC-HDD NPs prevented depolarization of mitochondrial membrane, reduced Bax/Bcl2 ratio and prevented externalization of phosphatidyl-serine confirming their anti-apoptotic capacity in those cells. Sub-G1 phase apparent in high glucose stressed cells was not seen in BC-HDD NPs treated cells. The present study reveals that BC-HDD NPs at ∼20 fold lower concentration are as effective as BBR in preventing high glucose induced oxidative stress, mitochondrial depolarization and downstream events of apoptotic cell death. PMID:24586539

  11. The potential of induced pluripotent stem cell derived hepatocytes.

    PubMed

    Hannoun, Zara; Steichen, Clara; Dianat, Noushin; Weber, Anne; Dubart-Kupperschmitt, Anne

    2016-07-01

    Orthotopic liver transplantation remains the only curative treatment for liver disease. However, the number of patients who die while on the waiting list (15%) has increased in recent years as a result of severe organ shortages; furthermore the incidence of liver disease is increasing worldwide. Clinical trials involving hepatocyte transplantation have provided encouraging results. However, transplanted cell function appears to often decline after several months, necessitating liver transplantation. The precise aetiology of the loss of cell function is not clear, but poor engraftment and immune-mediated loss appear to be important factors. Also, primary human hepatocytes (PHH) are not readily available, de-differentiate, and die rapidly in culture. Hepatocytes are available from other sources, such as tumour-derived human hepatocyte cell lines and immortalised human hepatocyte cell lines or porcine hepatocytes. However, all these cells suffer from various limitations such as reduced or differences in functions or risk of zoonotic infections. Due to their significant potential, one possible inexhaustible source of hepatocytes is through the directed differentiation of human induced pluripotent stem cells (hiPSCs). This review will discuss the potential applications and existing limitations of hiPSC-derived hepatocytes in regenerative medicine, drug screening, in vitro disease modelling and bioartificial livers. PMID:26916529

  12. INTEGRATED DISINFECTION BY-PRODUCTS (DBP) MIXTURES RESEARCH: GENE EXPRESSION ALTERATIONS IN PRIMARY RAT HEPATOCYTE CULTURES EXPOSED TO DBP MIXTURES FORMED BY CHLORINATION AND OZONATION/POSTCHLORINATION

    EPA Science Inventory

    What is the study?
    This study was designed to provide data on the in vitro toxicity of water concentrates containing complex mixtures of DBPs. Rat hepatocytes in primary culture were exposed for 24 hr to full strength, 1:10 or 1:20 dilutions of chlorination or ozonation/chl...

  13. GENE EXPRESSION ALTERATIONS OBSERVED IN PRIMARY CULTURED RAT HEPATOCYTES AFTER TREATMENT WITH CHLORINATED OR CHLORINATED AND OZONATED DRINKING WATER FROM EAST FORK LAKE, OHIO

    EPA Science Inventory

    Drinking water from East Fork Lake was spiked with iodide and bromide, disinfected with chlorine or ozone + chlorine, concentrated ~100-fold using reverse osmosis, and volatile disinfection by-products (DBPs) added back. Primary rat hepatocytes were exposed to full-strength, 1:10...

  14. Induction of Highly Functional Hepatocytes from Human Umbilical Cord Mesenchymal Stem Cells by HNF4α Transduction

    PubMed Central

    Huang, Qingfeng; Xia, Qiang; Bian, Jianmin

    2014-01-01

    Aim To investigate the differentiation potential of human umbilical mesenchymal stem cells (HuMSCs) and the key factors that facilitate hepatic differentiation. Methods HuMSCs were induced to become hepatocyte-like cells according to a previously published protocol. The differentiation status of the hepatocyte-like cells was examined by observing the morphological changes under an inverted microscope and by immunofluorescence analysis. Hepatocyte nuclear factor 4 alpha (HNF4α) overexpression was achieved by plasmid transfection of the hepatocyte-like cells. The expression of proteins and genes of interest was then examined by Western blotting and reverse transcription-polymerase chain reaction (RT-PCR) or real-time RT-PCR methods. Results Our results demonstrated that HuMSCs can easily be induced into hepatocyte-like cells using a published differentiation protocol. The overexpression of HNF4α in the induced HuMSCs significantly enhanced the expression levels of hepatic-specific proteins and genes. HNF4α overexpression may be associated with liver-enriched transcription factor networks and the Wnt/β-Catenin pathway. Conclusion The overexpression of HNF4α improves the hepatic differentiation of HuMSCs and is a simple way to improve cellular sources for clinical applications. PMID:25137413

  15. Engraftment of human induced pluripotent stem cell-derived hepatocytes in immunocompetent mice via 3D co-aggregation and encapsulation

    PubMed Central

    Song, Wei; Lu, Yen-Chun; Frankel, Angela S.; An, Duo; Schwartz, Robert E.; Ma, Minglin

    2015-01-01

    Cellular therapies for liver diseases and in vitro models for drug testing both require functional human hepatocytes (Hum-H), which have unfortunately been limited due to the paucity of donor liver tissues. Human pluripotent stem cells (hPSCs) represent a promising and potentially unlimited cell source to derive Hum-H. However, the hepatic functions of these hPSC-derived cells to date are not fully comparable to adult Hum-H and are more similar to fetal ones. In addition, it has been challenging to obtain functional hepatic engraftment of these cells with prior studies having been done in immunocompromised animals. In this report, we demonstrated successful engraftment of human induced pluripotent stem cell (iPSC)-derived hepatocyte-like cells (iPS-H) in immunocompetent mice by pre-engineering 3D cell co-aggregates with stromal cells (SCs) followed by encapsulation in recently developed biocompatible hydrogel capsules. Notably, upon transplantation, human albumin and α1-antitrypsin (A1AT) in mouse sera secreted by encapsulated iPS-H/SCs aggregates reached a level comparable to the primary Hum-H/SCs control. Further immunohistochemistry of human albumin in retrieved cell aggregates confirmed the survival and function of iPS-H. This proof-of-concept study provides a simple yet robust approach to improve the engraftment of iPS-H, and may be applicable to many stem cell-based therapies. PMID:26592180

  16. Total synthesis of biotinylated N domain of human hepatocyte growth factor.

    PubMed

    Raibaut, Laurent; Vicogne, Jérome; Leclercq, Bérénice; Drobecq, Hervé; Desmet, Rémi; Melnyk, Oleg

    2013-06-15

    Hepatocyte growth factor/scatter factor (HGF/SF) is the high affinity ligand of MET tyrosine kinase receptor. We report here the total synthesis of a biotinylated analogue of human HGF/SF N domain. Functionally, N domain is part of the HGF/SF high affinity binding site for MET and also the main HGF/SF binding site for heparin. The 97 Aa linear chain featuring a C-terminal biotin group was assembled in high yield using an N-to-C one-pot three segments assembly strategy relying on a sequential Native Chemical Ligation (NCL)/bis(2-sulfanylethyl)amido (SEA) native peptide ligation process. The folded protein displayed the native disulfide bond pattern and showed the ability to bind heparin. PMID:23523386

  17. Monoacylglycerol O-acyltransferase 1 is regulated by peroxisome proliferator-activated receptor γ in human hepatocytes and increases lipid accumulation

    SciTech Connect

    Yu, Jung Hwan; Lee, Yoo Jeong; Kim, Hyo Jung; Choi, Hyeonjin; Choi, Yoonjeong; Seok, Jo Woon; Kim, Jae-woo

    2015-05-08

    Monoacylglycerol O-acyltransferase (MGAT) is an enzyme that is involved in triglyceride synthesis by catalyzing the formation of diacylglycerol from monoacylglycerol and fatty acyl CoAs. Recently, we reported that MGAT1 has a critical role in hepatic TG accumulation and that its suppression ameliorates hepatic steatosis in a mouse model. However, the function of MGAT enzymes in hepatic lipid accumulation has not been investigated in humans. Unlike in rodents, MGAT3 as well as MGAT1 and MGAT2 are present in humans. In this study, we evaluated the differences between MGAT subtypes and their association with peroxisome proliferator-activated receptor γ (PPARγ), a regulator of mouse MGAT1 expression. In human primary hepatocytes, basal expression of MGAT1 was lower than that of MGAT2 or MGAT3, but was strongly induced by PPARγ overexpression. A luciferase assay as well as an electromobility shift assay revealed that human MGAT1 promoter activity is driven by PPARγ by direct binding to at least two regions of the promoter in 293T and HepG2 cells. Moreover, siRNA-mediated suppression of MGAT1 expression significantly attenuated lipid accumulation by PPARγ overexpression in HepG2 cells, as evidenced by oil-red-O staining. These results suggest that human MGAT1 has an important role in fatty liver formation as a target gene of PPARγ, and blocking MGAT1 activity could be an efficient therapeutic way to reduce nonalcoholic fatty liver diseases in humans. - Highlights: • PPARγ promotes MGAT1 expression in human primary hepatocytes. • PPARγ directly regulates MGAT1 promoter activity. • Human MGAT1 promoter has at least two PPARγ-binding elements. • Inhibition of MGAT1 expression attenuates hepatic lipid accumulation in humans.

  18. Expression and hepatobiliary transport characteristics of the concentrative and equilibrative nucleoside transporters in sandwich-cultured human hepatocytes

    PubMed Central

    Govindarajan, Rajgopal; Endres, Christopher J.; Whittington, Dale; LeCluyse, Edward; Pastor-Anglada, Marçal; Tse, Chung-Ming; Unadkat, Jashvant D.

    2008-01-01

    We previously reported that both the concentrative (hCNT) and equilibrative (hENT) nucleoside transporters are expressed in the human liver (21). Here we report a study that investigated the expression of these transporters (transcripts and proteins) and their role in the hepatobiliary transport of nucleosides/nucleoside drugs using sandwich-cultured human hepatocytes. In the hepatic tissue, the rank order of the mRNA expression of the transporters was hCNT1 ≈ hENT1 > hENT2 ≈ hCNT2 > hCNT3. In sandwich-cultured hepatocytes, the mRNA expression of hCNT2 and hENT2 was comparable to that in hepatic tissue, whereas the expression of corresponding transporters in the two-dimensional hepatocyte cultures was lower. Colocalization studies demonstrated predominant localization of these transporters at the sinusoidal membrane and of hENT1, hCNT1, and hCNT2 at the canalicular membrane. In the sandwich-cultured hepatocytes, ENTs were the major contributors to the transport of thymidine (hENT1, 63%; hENT2, 23%) or guanosine (hENT1, 53%; hENT2, 24%) into the hepatocytes followed by hCNT1 (10%) for thymidine or hCNT2 (23%) for guanosine. Although ribavirin was predominately transported (89%) into the hepatocytes by hENT1, fialuridine (FIAU) was transported by both hENT1 (30%) and hCNTs (61%). The extensively metabolized natural nucleosides were not effluxed into the bile, whereas significant biliary-efflux was observed of FIAU (19%), ribavirin (30%), and formycin B (35%). We conclude that the hepatic activity of hENT1 and hCNT1/2 transporters will determine the in vivo hepatic distribution and therefore the efficacy and/or toxicity of nucleoside drugs used to treat hepatic diseases. PMID:18635603

  19. Markers of electrophilic stress caused by chemically reactive metabolites in human hepatocytes.

    PubMed

    Takakusa, Hideo; Masumoto, Hiroshi; Mitsuru, Ayako; Okazaki, Osamu; Sudo, Kenichi

    2008-05-01

    The metabolic activation of a drug to an electrophilic reactive metabolite and its covalent binding to cellular macromolecules is considered to be involved in the occurrence of idiosyncratic drug toxicity (IDT). As a cellular defense system against oxidative and electrophilic stress, phase II enzymes are known to be induced through a Kelch-like ECH-associated protein 1/nuclear factor E2-related factor 2/antioxidant response element system. We presumed that it is important for the risk assessment of drug-induced hepatotoxicity and IDTs to observe the biological responses evoked by exposure to reactive metabolites, and then investigated the mRNA induction profiles of phase II enzymes in human hepatocytes after exposure to problematic drugs associated with IDTs, such as ticlopidine, diclofenac, clozapine, and tienilic acid, as well as safe drugs such as levofloxacin and caffeine. According to the results, the problematic drugs exhibited inductive effects on heme oxygenase 1 (HO-1), which contrasted with the safe drugs; therefore, the induction of HO-1 mRNA seems to be correlated with the occurrence of drug toxicity, including IDT caused by electrophilic reactive metabolites. Moreover, glutathione-depletion and cytochrome P450 (P450)-inhibition experiments have shown that the observed HO-1 induction was triggered by the electrophilic reactive metabolites produced from the problematic drugs through P450-mediated metabolic bioactivation. Taken together with our present study, this suggests that HO-1 induction in human hepatocytes would be a good marker of the occurrence of metabolism-based drug-induced hepatotoxicity and IDT caused by the formation of electrophilic reactive metabolites. PMID:18227147

  20. Suppresion of lipid peroxidation in rat hepatocytes in primary culture by supplemental zinc

    SciTech Connect

    Coppen, D.E.; Richardson, D.E.; Cousins, R.J.

    1986-03-05

    Rat liver parenchymal cells were cultured with 1-48 ..mu..M Zn for 18 h. Lactate dehydrogenase activity of the medium showed that the zinc concentrations used did not cause cell leakage. Incubation with zinc caused increases in cellular metallothionein from 0.1 mM at 1 ..mu..M Zn to 1.0 mM at 48 ..mu..M. Free radical and peroxidation production over a subsequent 2h period induced in the hepatocytes by 3-methylindole (8mM,3MI), t-butylhydroperoxide (2mM, TBHP) or a mixture of ferric -NTA and ascorbic acid (each at 10 ..mu..M, FE + AA) were measured. Peroxidation was assessed by malondialdehyde (MDA) content and free radicals by electron paramagnetic resonance (EPR) techniques. Supplemental zinc suppressed the production of both MDA and free radicals (as assessed by the amplitude of the EPR spectra) in the cells induced by either 3MI, TBHP or FE + AA. By virtue of its high sulfhydryl content, metallothionein may play a role in free radical scavenging. However, as the zinc concentration in the media was increased so the activity of the microsomal enzyme NADPH cytochrome c reductase was significantly decreased. Thus, it could be that the change in this enzyme activity reflects in part, the mechanism by which zinc is exerting its influence in suppression of free radical production.

  1. Human Embryonic and Rat Adult Stem Cells with Primitive Endoderm-Like Phenotype Can Be Fated to Definitive Endoderm, and Finally Hepatocyte-Like Cells

    PubMed Central

    Bose, Bipasha; Ordovas, Laura; Vanuytsel, Kim; Geraerts, Martine; Firpo, Meri; De Vos, Rita; Fevery, Johan; Nevens, Frederik; Hu, Wei-Shou; Verfaillie, Catherine M.

    2010-01-01

    Stem cell-derived hepatocytes may be an alternative cell source to treat liver diseases or to be used for pharmacological purposes. We developed a protocol that mimics mammalian liver development, to differentiate cells with pluripotent characteristics to hepatocyte-like cells. The protocol supports the stepwise differentiation of human embryonic stem cells (ESC) to cells with characteristics of primitive streak (PS)/mesendoderm (ME)/definitive endoderm (DE), hepatoblasts, and finally cells with phenotypic and functional characteristics of hepatocytes. Remarkably, the same protocol can also differentiate rat multipotent adult progenitor cells (rMAPCs) to hepatocyte-like cells, even though rMAPC are isolated clonally from cultured rat bone marrow (BM) and have characteristics of primitive endoderm cells. A fraction of rMAPCs can be fated to cells expressing genes consistent with a PS/ME/DE phenotype, preceding the acquisition of phenotypic and functional characteristics of hepatocytes. Although the hepatocyte-like progeny derived from both cell types is mixed, between 10–20% of cells are developmentally consistent with late fetal hepatocytes that have attained synthetic, storage and detoxifying functions near those of adult hepatocytes. This differentiation protocol will be useful for generating hepatocyte-like cells from rodent and human stem cells, and to gain insight into the early stages of liver development. PMID:20711405

  2. Lung fibroblasts accelerate wound closure in human alveolar epithelial cells through hepatocyte growth factor/c-Met signaling

    PubMed Central

    Correll, Kelly; Schiel, John A.; Finigan, Jay H.; Prekeris, Rytis; Mason, Robert J.

    2014-01-01

    There are 190,600 cases of acute lung injury/acute respiratory distress syndrome (ALI/ARDS) each year in the United States, and the incidence and mortality of ALI/ARDS increase dramatically with age. Patients with ALI/ARDS have alveolar epithelial injury, which may be worsened by high-pressure mechanical ventilation. Alveolar type II (ATII) cells are the progenitor cells for the alveolar epithelium and are required to reestablish the alveolar epithelium during the recovery process from ALI/ARDS. Lung fibroblasts (FBs) migrate and proliferate early after lung injury and likely are an important source of growth factors for epithelial repair. However, how lung FBs affect epithelial wound healing in the human adult lung has not been investigated in detail. Hepatocyte growth factor (HGF) is known to be released mainly from FBs and to stimulate both migration and proliferation of primary rat ATII cells. HGF is also increased in lung tissue, bronchoalveolar lavage fluid, and serum in patients with ALI/ARDS. Therefore, we hypothesized that HGF secreted by FBs would enhance wound closure in alveolar epithelial cells (AECs). Wound closure was measured using a scratch wound-healing assay in primary human AEC monolayers and in a coculture system with FBs. We found that wound closure was accelerated by FBs mainly through HGF/c-Met signaling. HGF also restored impaired wound healing in AECs from the elderly subjects and after exposure to cyclic stretch. We conclude that HGF is the critical factor released from FBs to close wounds in human AEC monolayers and suggest that HGF is a potential strategy for hastening alveolar repair in patients with ALI/ARDS. PMID:24748602

  3. Glucuronidation and Covalent Protein Binding of Benoxaprofen and Flunoxaprofen in Sandwich-Cultured Rat and Human Hepatocytes

    PubMed Central

    Dong, Jennifer Q.

    2009-01-01

    Benoxaprofen (BNX), a nonsteroidal anti-inflammatory drug (NSAID) that was withdrawn because of hepatotoxicity, is more toxic than its structural analog flunoxaprofen (FLX) in humans and rats. Acyl glucuronides have been hypothesized to be reactive metabolites and may be associated with toxicity. Both time- and concentration-dependent glucuronidation and covalent binding of BNX, FLX, and ibuprofen (IBP) were determined by exposing sandwich-cultured rat hepatocytes to each NSAID. The levels of glucuronide and covalent protein adduct measured in cells followed the order BNX > FLX > IBP. These results indicate that 1) BNX-glucuronide (G) is more reactive than FLX-G, and 2) IBP-G is the least reactive metabolite, which support previous in vivo studies in rats. The proportional increases of protein adduct formation for BNX, FLX, and IBP as acyl glucuronidation increased also support the hypothesis that part of the covalent binding of all three NSAIDs to hepatic proteins is acyl glucuronide-dependent. Moreover, theses studies confirmed the feasibility of using sandwich-cultured rat hepatocytes for studying glucuronidation and covalent binding to hepatocellular proteins. These studies also showed that these in vitro methods can be applied using human tissues for the study of acyl glucuronide reactivity. More BNX-protein adduct was formed in sandwich-cultured human hepatocytes than FLX-protein adduct, which not only agreed with its relative toxicity in humans but also was consistent with the in vitro findings using rat hepatocyte cultures. These data support the use of sandwich-cultured human hepatocytes as an in vitro screening model of acyl glucuronide exposure and reactivity. PMID:19773537

  4. Differentiation of human embryonic stem cells to hepatocyte-like cells on a new developed xeno-free extracellular matrix.

    PubMed

    Farzaneh, Zahra; Pakzad, Mohammad; Vosough, Massoud; Pournasr, Behshad; Baharvand, Hossein

    2014-08-01

    Human embryonic stem cells (hESCs) provide a new source for hepatocyte production in translational medicine and cell replacement therapy. The reported hESC-derived hepatocyte-like cells (HLCs) were commonly generated on Matrigel, a mouse cell line-derived extracellular matrix (ECM). Here, we performed the hepatic lineage differentiation of hESCs following a stepwise application of growth factors on a newly developed serum- and xeno-free, simple and cost-benefit ECM, designated "RoGel," which generated from a modified conditioned medium of human fibroblasts. In comparison with Matrigel, the differentiated HLCs on both ECMs expressed similar levels of hepatocyte-specific genes, secreted α-fetoprotein, and metabolized ammonia, showed glycogen storage activity as well as low-density lipoprotein and indocyanine green uptake. The transplantation of hESC-HLCs into the carbon tetrachloride-injured liver demonstrated incorporation of the cells into the host mouse liver and the expression of albumin. The results suggest that the xeno-free and cost-benefit matrix may be applicable in bioartificial livers and also may facilitating a clinical application of human pluripotent stem cell-derived hepatocytes in the future. PMID:24477550

  5. Human hepatocytes express absent in melanoma 2 and respond to hepatitis B virus with interleukin-18 expression.

    PubMed

    Pan, Xingfei; Xu, Haixia; Zheng, Changlong; Li, Mei; Zou, Xiaofang; Cao, Hong; Xu, Qihuan

    2016-08-01

    Absent in melanoma 2 (AIM2) is a recently recognized cytoplasmic receptor which could sense cytoplasmic double-stranded DNA (dsDNA). After AIM2 detects the presence of parasitic nucleic acids (dsDNA) derived from invasive bacteria or viral genomes (for example, vaccinia virus and cytomegalovirus) within infected cells, AIM2 inflammasome could be formed. The formed AIM2 inflammasome could induce innate immune response and increase expressions of IL-1β and IL-18. Hepatitis B virus (HBV) is a hepatotropic, non-cytopathic double-stranded DNA virus. The immune response to viral antigens or virus is thought to be responsible for both liver damage and viral clearance in patients with HBV infection. However, there are no reports about whether AIM2 inflammasome exists in hepatocytes. In the present study, we investigated the presence and activity of AIM2 inflammasome in human hepatocytes. We found that AIM2 was expressed in cytoplasm of hepatocytes, and IL-18 expression was increased after AIM2 sensed HBV in hepatocytes in vitro. These results showed that AIM2 inflammasome was active in hepatocytes. We also found that hepatic AIM2 expression of chronic hepatitis B (CHB) patients was higher than that of controls. Hepatic AIM2 expression levels were positively correlated to the severity of liver inflammation. IL-18 is already considered to be associated with hepatic injury during HBV infection. In conclusion, we, therefore, believe that AIM2 inflammasome in hepatocytes might play an important role in the development and maintenance of HBV-related hepatitis. PMID:27094165

  6. The mutated human gene encoding hepatocyte nuclear factor 1β inhibits kidney formation in developing Xenopus embryos

    PubMed Central

    Wild, Wiltrud; Pogge von Strandmann, Elke; Nastos, Aristotelis; Senkel, Sabine; Lingott-Frieg, Anja; Bulman, Michael; Bingham, Coralie; Ellard, Sian; Hattersley, Andrew T.; Ryffel, Gerhart U.

    2000-01-01

    The transcription factor hepatocyte nuclear factor 1β (HNF1β) is a tissue-specific regulator that also plays an essential role in early development of vertebrates. In humans, four heterozygous mutations in the HNF1β gene have been identified that lead to early onset of diabetes and severe primary renal defects. The degree and type of renal defects seem to depend on the specific mutation. We show that the frameshift mutant P328L329fsdelCCTCT associated with nephron agenesis retains its DNA-binding properties and acts as a gain-of-function mutation with increased transactivation potential in transfection experiments. Expression of this mutated factor in the Xenopus embryo leads to defective development and agenesis of the pronephros, the first kidney form of amphibians. Very similar defects are generated by overexpressing in Xenopus the wild-type HNF1β, which is consistent with the gain-of-function property of the mutant. In contrast, introduction of the human HNF1β mutant R137-K161del, which is associated with a reduced number of nephrons with hypertrophy of the remaining ones and which has an impaired DNA binding, shows only a minor effect on pronephros development in Xenopus. Thus, the overexpression of both human mutants has a different effect on renal development in Xenopus, reflecting the variation in renal phenotype seen with these mutations. We conclude that mutations in human HNF1β can be functionally characterized in Xenopus. Our findings imply that HNF1β not only is an early marker of kidney development but also is functionally involved in morphogenetic events, and these processes can be investigated in lower vertebrates. PMID:10758154

  7. Cytochrome P450 induction response in tethered spheroids as a three-dimensional human hepatocyte in vitro model.

    PubMed

    Xia, Lei; Hong, Xin; Sakban, Rashidah Binte; Qu, Yinghua; Singh, Nisha Hari; McMillian, Michael; Dallas, Shannon; Silva, Jose; Sensenhauser, Carlo; Zhao, Sylvia; Lim, Heng Keang; Yu, Hanry

    2016-02-01

    Cytochrome P450 (CYP) induction is a key risk factor of clinical drug-drug interactions that has to be mitigated in the early phases of drug discovery. Three-dimensional (3D) cultures of hepatocytes in vitro have recently emerged as a potentially better platform to recapitulate the in vivo liver structure and to maintain long-term hepatic functions as compared with conventional two-dimensional (2D) monolayer cultures. However, the majority of published studies on 3D hepatocyte models use rat hepatocytes and the response to CYP inducers between rodents and humans is distinct. In the present study, we constructed tethered spheroids on RGD/galactose-conjugated membranes as an in vitro 3D model using cryopreserved human hepatocytes. CYP3A4 mRNA expression in the tethered spheroids was induced to a significantly greater extent than those in the collagen sandwich cultures, indicating the transcriptional regulation was more sensitive to the CYP inducers in the 3D model. Induction of CYP1A2, CYP2B6 and CYP3A4 activities in the tethered spheroids were comparable to, if not higher than that observed in the collagen sandwich cultures. The membrane-based model is readily integrated into multi-well plates for higher-throughput drug testing applications, which might be an alternative model to screen the CYP induction potential in vitro with more physiological relevance. PMID:26201057

  8. Cultivation of primary porcine hepatocytes in an OXY-HFB for use as a bioartificial liver device.

    PubMed

    Jasmund, Inka; Langsch, Angelika; Simmoteit, Robert; Bader, Augustinus

    2002-01-01

    Bioreactors being developed for bioartificial liver devices vary greatly in their construction. Until now, primary liver cells were cultivated either in sandwich configuration, as spheroids, or in special hollow fiber systems. Primary hepatocytes are demanding on their environment and have a high oxygen consumption. To get good results, optimal cultivation conditions are needed. The idea of the project was to investigate a new concept of an oxygenating hollow fiber bioreactor (OXY-HFB). The OXY-HFB should consist exclusively of oxygenating and internal heat exchange fibers to yield a simple and effective design. Primary liver cells were seeded on the surface of the fibers in the extrafiber space. Oxygen requirements and temperature control were supplied through the fibers. The culture medium was perfused through the extrafiber space and therefore brought into direct hepatocellular contact. The OXY-HFB concept offers different advantages. A high cell density of 2.5 x 10(7) cells/mL can be obtained. This results in a cell number of 2.5 x 10(9) liver cells per bioreactor. Furthermore, the OXY-HFB is easily handled because no incubator is required. To study the efficiency of this bioreactor technique, various parameters were investigated over a cultivation period of three weeks. These included urea synthesis, lactate formation, glucose elimination, albumin synthesis, oxygen level, and pH. Furthermore, the metabolites of diazepam were measured. The biochemical performance of the bioreactor remained stable over the investigated time period. These results demonstrate that porcine liver cells preserve their viability and primary metabolism in the OXY-HFB over the complete period of study. PMID:12153319

  9. A Schisandra-Derived Compound Schizandronic Acid Inhibits Entry of Pan-HCV Genotypes into Human Hepatocytes.

    PubMed

    Qian, Xi-Jing; Zhang, Xiao-Lian; Zhao, Ping; Jin, Yong-Sheng; Chen, Hai-Sheng; Xu, Qing-Qiang; Ren, Hao; Zhu, Shi-Ying; Tang, Hai-Lin; Zhu, Yong-Zhe; Qi, Zhong-Tian

    2016-01-01

    Despite recent progress in the development of hepatitis C virus (HCV) inhibitors, cost-effective antiviral drugs, especially among the patients receiving liver transplantations, are still awaited. Schisandra is a traditional medicinal herb used to treat a range of liver disorders including hepatitis for thousands of years in China. To isolate the bioactive compounds of schisandra for the treatment of HCV infection, we screened a schisandra-extracts library and identified a tetracyclic triterpenoid, schizandronic acid (SZA), as a novel HCV entry inhibitor. Our findings suggested that SZA potently inhibited pan-HCV genotype entry into hepatoma cells and primary human hepatocytes without interfering virus binding on cell surface or internalization. However, virion-cell fusion process was impaired in the presence of SZA, along with the increased host membrane fluidity. We also found that SZA inhibited the spread of HCV to the neighboring cells, and combinations of SZA with interferon or telaprevir resulted in additive synergistic effect against HCV. Additionally, SZA diminished the establishment of HCV infection in vivo. The SZA target is different from conventional direct-acting antiviral agents, therefore, SZA is a potential therapeutic compound for the development of effective HCV entry inhibitors, especially for patients who need to prevent HCV reinfection during the course of liver transplantations. PMID:27252043

  10. A Schisandra-Derived Compound Schizandronic Acid Inhibits Entry of Pan-HCV Genotypes into Human Hepatocytes

    PubMed Central

    Qian, Xi-Jing; Zhang, Xiao-Lian; Zhao, Ping; Jin, Yong-Sheng; Chen, Hai-Sheng; Xu, Qing-Qiang; Ren, Hao; Zhu, Shi-Ying; Tang, Hai-Lin; Zhu, Yong-Zhe; Qi, Zhong-Tian

    2016-01-01

    Despite recent progress in the development of hepatitis C virus (HCV) inhibitors, cost-effective antiviral drugs, especially among the patients receiving liver transplantations, are still awaited. Schisandra is a traditional medicinal herb used to treat a range of liver disorders including hepatitis for thousands of years in China. To isolate the bioactive compounds of schisandra for the treatment of HCV infection, we screened a schisandra-extracts library and identified a tetracyclic triterpenoid, schizandronic acid (SZA), as a novel HCV entry inhibitor. Our findings suggested that SZA potently inhibited pan-HCV genotype entry into hepatoma cells and primary human hepatocytes without interfering virus binding on cell surface or internalization. However, virion-cell fusion process was impaired in the presence of SZA, along with the increased host membrane fluidity. We also found that SZA inhibited the spread of HCV to the neighboring cells, and combinations of SZA with interferon or telaprevir resulted in additive synergistic effect against HCV. Additionally, SZA diminished the establishment of HCV infection in vivo. The SZA target is different from conventional direct-acting antiviral agents, therefore, SZA is a potential therapeutic compound for the development of effective HCV entry inhibitors, especially for patients who need to prevent HCV reinfection during the course of liver transplantations. PMID:27252043

  11. Hepatoprotective and antioxidative effects of total phenolics from Laggera pterodonta on chemical-induced injury in primary cultured neonatal rat hepatocytes.

    PubMed

    Wu, Yihang; Yang, Leixiang; Wang, Fang; Wu, Xiumei; Zhou, Changxin; Shi, Shuyun; Mo, Jianxia; Zhao, Yu

    2007-08-01

    Although Laggera pterodonta as a folk medicine has been widely used for several centuries to ameliorate some inflammatory ailments as hepatitis in China, there have been no studies of the hepatoprotective and antioxidative effects of this plant. In this paper, the hepatoprotective effect of total phenolics from L. pterodonta (TPLP) against CCI4-, D-GalN-, TAA-, and t-BHP-induced injury was examined in primary cultured neonatal rat hepatocytes. TPLP inhibited the cellular leakage of two enzymes, hepatocyte ASAT and ALAT, caused by these chemicals and improved cell viability. Moreover, TPLP afforded much stronger protection than the reference drug silibinin. Meanwhile, DPPH and superoxide radicals scavenging activities of TPLP were also determined. The present investigation is the first to report chemical-induced injury model in primary cultured neonatal rat hepatocytes and provide evidence for the hepatoprotective and antioxidative effects of L. pterodonta. Neutralizing reactive oxygen species by nonenzymatic mechanisms may be one of main mechanisms of TPLP against chemical-induced hepatocyte injury. Furthermore, The total phenolic content of L. pterodonta and its main component type were quantified, and its principle components isochlorogenic acids were isolated and authenticated. These data support the folkloric uses of L. pterodonta in the treatment of hepatitis. PMID:17329003

  12. GW4064, an agonist of farnesoid X receptor, represses CYP3A4 expression in human hepatocytes by inducing small heterodimer partner expression.

    PubMed

    Zhang, Shu; Pan, Xian; Jeong, Hyunyoung

    2015-05-01

    Farnesoid X receptor (FXR) functions as a regulator of bile acid and lipid homeostasis and is recognized as a promising therapeutic target for metabolic diseases. The biologic function of FXR is mediated in part by a small heterodimer partner (SHP); ligand-activated FXR enhances SHP expression, and SHP in turn represses the activity of multiple transcription factors. This study aimed to investigate the effect of FXR activation on expression of the major drug-metabolizing enzyme CYP3A4. The effects of 3-(2,6-dichlorophenyl)-4-(3'-carboxy-2-chlorostilben-4-yl)oxymethyl-5-isopropylisoxazole (GW4064), a synthetic agonist of FXR, on the expression and activity of CYP3A4 were examined in primary human hepatocytes by using quantitative real-time polymerase chain reaction and S9 phenotyping. In human hepatocytes, treatment of GW4064 (1 μM) for 48 hours resulted in a 75% decrease in CYP3A4 mRNA expression and a 25% decrease in CYP3A4 activity, accompanied by ∼3-fold increase in SHP mRNA expression. In HepG2 cells, SHP repressed transactivation of CYP3A4 promoter by pregnane X receptor (PXR), constitutive androstane receptor (CAR), and glucocorticoid receptor. Interestingly, GW4064 did not repress expression of CYP2B6, another target gene of PXR and CAR; GW4064 enhanced CYP2B6 promoter activity. In conclusion, GW4064 represses CYP3A4 expression in human hepatocytes, potentially through upregulation of SHP expression and subsequent repression of CYP3A4 promoter activity. Clinically significant drug-drug interaction involving FXR agonists and CYP3A4 substrates may occur. PMID:25725071

  13. Rat primary hepatocytes show enhanced performance and sensitivity to acetaminophen during three-dimensional culture on a polystyrene scaffold designed for routine use.

    PubMed

    Schutte, Maaike; Fox, Bridget; Baradez, Marc-Olivier; Devonshire, Alison; Minguez, Jesus; Bokhari, Maria; Przyborski, Stefan; Marshall, Damian

    2011-10-01

    The in vitro evaluation of hepatotoxicity is an essential stage in the research and development of new pharmaceuticals as the liver is one of the most commonly impacted organs during preclinical toxicity studies. Fresh primary hepatocytes in monolayer culture are the most commonly used in vitro model of the liver but often exhibit limited viability and/or reduction or loss of important liver-specific functions. These limitations could potentially be overcome using three-dimensional (3D) culture systems, but their experimental nature and limited use in liver toxicity screening and drug metabolism has impaired their uptake into commercial screening programs. In this study we use a commercially available polystyrene scaffold developed for routine 3D cell culture to maintain primary rat hepatocytes for use in metabolism and toxicity studies over 72 h. We show that primary hepatocytes retain their natural cuboidal morphology with significantly higher viability (>74%) than cells grown in monolayer culture (maximum of 57%). Hepatocytes in the 3D scaffolds exhibit differential expression of genes associated with phase I, II, and III drug metabolism under basal conditions compared with monolayer culture and can be induced to stably express significantly higher levels of the cytochrome-P450 enzymes 1A2, 2B1, and 3A2 over 48 h. In toxicity studies the hepatocytes in the 3D scaffolds also show increased sensitivity to the model toxicant acetaminophen. These improvements over monolayer culture and the availability of this new easy to use 3D scaffold system could facilitate the uptake of 3D technologies into routine drug screening programs. PMID:21675871

  14. Cytochrome P4501A induction by 2,3,7,8-tetrachlorodibenzo-p-dioxin and two chlorinated dibenzofurans in primary hepatocyte cultures of three avian species.

    PubMed

    Hervé, Jessica C; Crump, Doug; Jones, Stephanie P; Mundy, Lukas J; Giesy, John P; Zwiernik, Matthew J; Bursian, Steven J; Jones, Paul D; Wiseman, Steve B; Wan, Yi; Kennedy, Sean W

    2010-02-01

    Relative potencies of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), and 2,3,7,8-tetrachlorodibenzofuran (TCDF) were determined in vitro in primary hepatocyte cultures of chicken (Gallus gallus), ring-necked pheasant (Phasianus colchicus), and Japanese quail (Coturnix japonica) embryos. Concentration-dependent effects on ethoxyresorufin O-deethylase (EROD) activity and expression of cytochrome P4501A4 and cytochrome P4501A5 (CYP1A4 and CYP1A5) messenger RNA (mRNA) were determined in hepatocytes exposed to serial dilutions of TCDD, PeCDF, or TCDF for 24 h. In chicken hepatocytes, the three compounds were equipotent inducers of EROD activity and CYP1A4/CYP1A5 mRNA expression. However, in ring-necked pheasant and Japanese quail hepatocytes, PeCDF was more potent than TCDD (3- to 5-fold in ring-necked pheasant and 13- to 30-fold in Japanese quail). Among species, the rank order of sensitivity (most to least) to EROD and CYP1A4/CYP1A5 mRNA induction for TCDD and TCDF was chicken > ring-necked pheasant > Japanese quail. In contrast, the three species were approximately equisensitive to EROD and CYP1A4/CYP1A5 mRNA induction by PeCDF. It has generally been assumed that TCDD is the most potent "dioxin-like compound" (DLC) and that the chicken is the most sensitive avian species to CYP1A induction by all DLCs. This study indicates that PeCDF is more potent than TCDD in ring-necked pheasant and Japanese quail hepatocytes and that ring-necked pheasant, Japanese quail, and chicken hepatocytes are equally sensitive to CYP1A induction by PeCDF. PMID:19884122

  15. Evaluation of cytochrome P450 inductions by anti-epileptic drug oxcarbazepine, 10-hydroxyoxcarbazepine, and carbamazepine using human hepatocytes and HepaRG cells.

    PubMed

    Sugiyama, Ikuo; Murayama, Norie; Kuroki, Ayaka; Kota, Jagannath; Iwano, Shunsuke; Yamazaki, Hiroshi; Hirota, Takashi

    2016-09-01

    Anti-epileptic drug oxcarbazepine is structurally related to carbamazepine, but has reportedly different metabolic pathway. Auto-induction potentials of oxcarbazepine, its pharmacologically active metabolite 10-hydroxyoxcarbazepine and carbamazepine were evaluated by cytochrome P450 (CYP) 1A2, CYP2B6 and CYP3A4 mRNA levels and primary metabolic rates using human hepatocytes and HepaRG cells. For the CYP1A2 the induction potential determined as the fold change in mRNA levels was 7.2 (range: 2.3-11.5) and 10.0 (6.2-13.7) for oxcarbazepine and carbamazepine, respectively, while 10-hydroxyoxcarbazepine did not induce. The fold change in mRNA levels for CYP2B6 was 11.5 (3.2-19.3), 7.0 (2.5-10.8) and 14.8 (3.1-29.1) for oxcarbazepine, 10-hydroxyoxcarbazepine and carbamazepine, respectively. The fold change for CYP3A4 induction level by oxcarbazepine, 10-hydroxyoxcarbazepine and carbamazepine was 3.5 (1.2-7.4), 2.7 (0.8-5.7) and 8.3 (3.5-14.5), respectively. The data suggest lower induction potential of oxcarbazepine and 10-hydroxyoxcarbazepine relative to carbamazepine. The results in HepaRG cells showed similar trend as the human hepatocytes. After incubation for 72 h in hepatocytes and HepaRG cells, auto-induction was evident for only carbamazepine metabolism. The 10-keto group instead of double bond at C10 position is evidently a determinant factor for limited auto-induction of P450 enzymes by oxcarbazepine. PMID:26711482

  16. Peroxisome proliferator-activated receptor gamma (PPARγ) in brown trout: Interference of estrogenic and androgenic inputs in primary hepatocytes.

    PubMed

    Lopes, Célia; Madureira, Tânia Vieira; Ferreira, Nádia; Pinheiro, Ivone; Castro, L Filipe C; Rocha, Eduardo

    2016-09-01

    Peroxisome proliferator-activated receptor gamma (PPARγ) is a pivotal regulator of lipid and glucose metabolism in vertebrates. Here, we isolated and characterized for the first time the PPARγ gene from brown trout (Salmo trutta f. fario). Hormones have been reported to interfere with the regulatory function of PPARγ in various organisms, albeit with little focus on fish. Thus, primary hepatocytes isolated from juveniles of brown trout were exposed to 1, 10 and 50μM of ethinylestradiol (EE2) or testosterone (T). A significant (3 fold) decrease was obtained in response to 50μM of EE2 and to 10 and 50μM of T (13 and 14 folds), while a 3 fold increase was observed at 1μM of EE2. Therefore, trout PPARγ seems a target for natural/synthetic compounds with estrogenic or androgenic properties and so, we advocate considering PPARγ as another alert sensor gene when assessing the effects of sex-steroid endocrine disruptors. PMID:27541269

  17. Inhibitory effect of leupeptin on the intracellular maturation of lysosomal cathepsin L in primary cultures of rat hepatocytes.

    PubMed

    Nishimura, Y; Kato, K; Furuno, K; Himeno, M

    1995-07-01

    To investigate the intracellular processing event for lysosomal cathespin L, we examined the effect of leupeptin, a non-covalent cysteine proteinase inhibitor, on the intracellular processing kinetics of cathepsin L as analyzed by pulse-chase experiments in vivo with [35S]methionine in primary cultures of rat hepatocytes. This revealed that cathepsin L was initially synthesized as proenzyme of molecular weight 39 kDa and the proenzyme was subsequently processed to the mature form of the enzyme, 30 and 25 kDa. In the leupeptin-treated cells, the proteolytic conversion of cellular procathepsin L, of molecular weight 39 kDa, to the mature enzyme was significantly inhibited and considerable amounts of proenzyme were found in the cell after 8 h chase periods. Furthermore, the subcellular fractionation experiment demonstrated that the intracellular processing of procathepsin L in the high density lysosomal fraction was significantly inhibited and that considerable amounts of the procathepsin L form were still observed in the dense lysosomal fraction after a 2 h chase period. These results suggest that leupeptin treatment caused significant inhibition of the intracellular maturation of cathepsin L. These findings show that cysteine proteinase plays an important role in the intracellular proteolytic processing and activation of lysosomal cathepsin L in vivo and that this processing event occurs within the lysosomes. PMID:7581248

  18. Studies on the metabolism of metallothionein and alkaline phosphatase of adult rat primary hepatocyte cultures: role of fetal calf serum and agonists of the phosphoinositide cascade.

    PubMed

    Krämer, K; Markwitan, A; Pallauf, J

    1993-09-01

    Adult rat primary hepatocytes maintained in DMEM/F12 (Ham) media were used as a model system for studying the role of fetal calf serum (FCS) and agonists of the phosphoinositide cascade in the metabolism of metallothionein (MT) and alkaline phosphatase (ALP). Experiments were performed both after a 24 h preincubation with FCS and with bovine serum albumin (BSA). Hepatocytes were treated with dexamethasone (DEX), zinc (Zn) and with the agonists of the phosphoinositide cascade A23187, 1,2-dioctanoyl-sn-glycerol (DiC8), 12-O-tetradecanoylphorbol-13-acetate (TPA), angiotensin II (AT), platelet activating factor (PAF), Arg8-vasopressin (VP) and were analyzed for MT and ALP activity in cell homogenates. Cell viability was evaluated by lactate dehydrogenase (LDH) liberation into culture medium, induction of tyrosine aminotransferase (TAT) through DEX and by trypan blue exclusion. Overall, cell viability was improved by the FCS pretreatment and by DEX. Exposure of hepatocytes to the established direct inducers Zn and DEX of MT resulted in a manifold increase in MT, independent of whether the cultures were FCS pretreated or not. The FCS preincubation produced a moderate elevation of ALP activity by stimulating cell viability. However, ALP was unaltered in response to Zn and DEX. None of the experiments conducted with agonists of the phosphoinositide cascade led to an elevation of MT and ALP. Only the incubation of hepatocytes with A23187 resulted in a concentration dependent significant decrease of MT and ALP. This observation was due to a cytotoxic effect of A 23187, displayed by LDH leakage and an increase in the number of cells stained with trypan blue. In conclusion, in primary hepatocyte cultures agonists of the phosphoinositide did not have an effect on the metabolism of MT and ALP. Previous in vivo results indicating alterations of Zn metabolism in liver, therefore seem to be caused by indirect systemic responses. PMID:8237077

  19. Combined use of N-acetylcysteine and Liberase improves the viability and metabolic function of human hepatocytes isolated from human liver

    PubMed Central

    Bartlett, David C.; Hodson, James; Bhogal, Ricky H.; Youster, Janine; Newsome, Phil N.

    2014-01-01

    Background aims Successful hepatocyte isolation is critical for continued development of cellular transplantation. However, most tissue available for research is from diseased liver, and the results of hepatocyte isolation from such tissue are inferior compared with normal tissue. Liberase and N-acetylcysteine (NAC) have been shown separately to improve viability of isolated hepatocytes. This study aims to determine the effect of Liberase and NAC in combination on human hepatocyte isolation from normal and diseased liver tissues. Methods Hepatocytes were isolated from 30 liver specimens through the use of a standard collagenase digestion technique (original protocol) and another 30 with the addition of NAC and standard collagenase substituted by Liberase (new protocol). Viability and success, defined as maintenance of cell adhesion and morphology for 48 hours, were assessed. Metabolic function was assessed by means of albumin and urea synthesis. Results Baseline factors were similar for both groups. The delay to tissue processing was slightly shorter in the new protocol group (median, 2 versus 4 hours; P = 0.007). The success rate improved from 12 of 30 (40.0%) to 21 of 30 (70.0%) with the use of the new protocol (P = 0.037), and median viable cell yield increased from 7.3 × 104 to 28.3 × 104 cells/g tissue (P = 0.003). After adjusting for delay, success rate (P = 0.014) and viable cell yield/g tissue (P = 0.001) remained significantly improved. Albumin and urea synthesis were similar or superior in the new protocol group. Conclusions NAC and Liberase improve the success of hepatocyte isolation, with a significantly higher yield of viable cells. The use of these agents may improve the availability of hepatocytes for transplantation and laboratory research. PMID:24642019

  20. Hepatocyte growth factor (HGF) signals through SHP2 to regulate primary mouse myoblast proliferation

    SciTech Connect

    Li, Ju; Reed, Sarah A.; Johnson, Sally E.

    2009-08-01

    Niche localized HGF plays an integral role in G{sub 0} exit and the return to mitotic activity of adult skeletal muscle satellite cells. HGF actions are regulated by MET initiated intracellular signaling events that include recruitment of SHP2, a protein tyrosine phosphatase. The importance of SHP2 in HGF-mediated signaling was examined in myoblasts and primary cultures of satellite cells. Myoblasts stably expressing SHP2 (23A2-SHP2) demonstrate increased proliferation rates by comparison to controls or myoblasts expressing a phosphatase-deficient SHP2 (23A2-SHP2DN). By comparison to 23A2 myoblasts, treatment of 23A2-SHP2 cells with HGF does not further increase proliferation rates and 23A2-SHP2DN myoblasts are unresponsive to HGF. Importantly, the effects of SHP2 are independent of downstream ERK1/2 activity as inclusion of PD98059 does not blunt the HGF-induced proliferative response. SHP2 function was further evaluated in primary satellite cell cultures. Ectopic expression of SHP2 in satellite cells tends to decrease proliferation rates and siSHP2 causes an increase the percentage of dividing myogenic cells. Interestingly, treatment of satellite cells with high concentrations of HGF (50 ng/ml) inhibits proliferation, which can be overcome by knockdown of SHP2. From these results, we conclude that HGF signals through SHP2 in myoblasts and satellite cells to directly alter proliferation rates.

  1. Hepatoprotective Activity of Water Extracts from Chaga Medicinal Mushroom, Inonotus obliquus (Higher Basidiomycetes) Against Tert-Butyl Hydroperoxide-Induced Oxidative Liver Injury in Primary Cultured Rat Hepatocytes.

    PubMed

    Hong, Ki Bae; Noh, Dong Ouk; Park, Yooheon; Suh, Hyung Joo

    2015-01-01

    We examined the hepatoprotective activity of Inonotus obliquus water extract (IO-W) against tert-butyl hydroperoxide (t-BHP)-induced oxidative liver injury in the primary cultured rat hepatocyte. The 50% radical scavenging concentrations (SC50s) of IO-W for radical-scavenging activity against 2,2'-azino-bis-(3-ethylbenzothi- azoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) were 5.19 mg/mL and 0.39 mg/mL, respectively. IO-W pretreatment to the primary cultured hepatocytes significantly (p<0.05) protected the cells from t-BHP-induced cytotoxic injury even at a low concentration of IO-W (10 µg/mL). The cellular leakage of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH), as well as malondialdehyde (MDA) formation caused by t-BHP were significantly (p<0.05) suppressed by IO-W pretreatment (>100 µg/ mL). In conclusion, this study demonstrates that IO-W exhibited hepatoprotective activity against t-BHP-induced oxidative liver injury in the primary cultured hepatocyte probably via its abilities of quenching free radicals, inhibiting the leakage of ALT, AST, and LDH, and decreasing MDA formation. PMID:26853962

  2. Hepatocyte growth factor protects human endothelial cells against advanced glycation end products-induced apoposis

    SciTech Connect

    Zhou Yijun . E-mail: zhou-yijun@hotmail.com; Wang Jiahe; Zhang Jin

    2006-06-02

    Advanced glycation end products (AGEs) form by a non-enzymatic reaction between reducing sugars and biological proteins, which play an important role in the pathogenesis of atherosclerosis. In this study, we assessed AGEs effects on human umbilical vein endothelial cells (HUVECs) growth, proliferation and apoptosis. Additionally, we investigated whether hepatocyte growth factor (HGF), an anti-apoptotic factor for endothelial cells, prevents AGEs-induced apoptosis of HUVECs. HUVECs were treated with AGEs in the presence or absence of HGF. Treatment of HUVECs with AGEs changed cell morphology, decreased cell viability, and induced DNA fragmentation, leading to apoptosis. Apoptosis was induced by AGEs in a dose- and time-dependent fashion. AGEs markedly elevated Bax and decreased NF-{kappa}B, but not Bcl-2 expression. Additionally, AGEs significantly inhibited cell growth through a pro-apoptotic action involving caspase-3 and -9 activations in HUVECs. Most importantly, pretreatment with HGF protected against AGEs-induced cytotoxicity in the endothelial cells. HGF significantly promoted the expression of Bcl-2 and NF-{kappa}B, while decreasing the activities of caspase-3 and -9 without affecting Bax level. Our data suggest that AGEs induce apoptosis in endothelial cells. HGF effectively attenuate AGEs-induced endothelial cell apoptosis. These findings provide new perspectives in the role of HGF in cardiovascular disease.

  3. Uptake and metabolism of vinca alkaloids by freshly isolated human hepatocytes in suspension.

    PubMed

    Zhou, X J; Placidi, M; Rahmani, R

    1994-01-01

    A study was carried out to evaluate the uptake, release and metabolism of four currently used vinca alkaloids, including vinblastine, vincristine, vindesine and navelbine, using freshly isolated human hepatocytes in suspension. The drugs were rapidly taken up and intensely metabolised by the cells, giving a number of yet unidentified biotransformation products. Navelbine was the most rapidly and intensely accumulated drug followed by vinblastine, vindesine and vincristine. The extent of cell uptake appeared to parallel the lipophilicities of these compounds. Interestingly, we found a significant correlation between the mean uptake rates of the vinca alkaloids into the cells, which were 0.279, 0.343, 0.568 and 0.834 pmol/min/10(6) cells for vincristine, vindesine, vinblastine and navelbine, respectively, and the in vivo plasma clearances of the drugs (r = 0.9995, p < 0.001). This finding is of great importance as regards a better understanding of the structure-activity relationship among this class of antitumour drugs, as well as a reliable extrapolation of in vitro results to the in vivo situation. PMID:8074443

  4. Glucocorticoid-dependent induction of interleukin-6 receptor expression in human hepatocytes facilitates interleukin-6 stimulation of amino acid transport.

    PubMed Central

    Fischer, C P; Bode, B P; Takahashi, K; Tanabe, K K; Souba, W W

    1996-01-01

    OBJECTIVE: The authors studied the effects of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) on glutamine and alanine transport in isolated human hepatocytes. They also evaluated the role of dexamethasone in modulating this response and its effects on the expression of the plasma membrane high-affinity IL-6 receptor. SUMMARY BACKGROUND DATA: Animal studies indicate that cytokines are important mediators of the increased hepatic amino acid uptake that occurs during cancer and sepsis, but studies in human tissues are lacking. The control of transport by cytokines and cytokine receptor expression in the liver may provide a mechanism by which hepatocytes can modulate amino acid availability during catabolic disease states. METHODS: Human hepatocytes were isolated from wedge biopsy specimens and plated in 24-well trays. Interleukin-6 and TNF-alpha, in combination with the synthetic glucocorticoid dexamethasone, were added to hepatocytes in culture, and the transport of radiolabeled glutamine and alanine was measured. Fluorescent-activated cell sorter (FACS) analysis was used to study the effects of dexamethasone on IL-6 receptor number in the well-differentiated human hepatoma HepG2. RESULTS: Both IL-6 and TNF-alpha exerted a small stimulatory effect on alanine and glutamine transport. Dexamethasone alone did not alter transport rates, but pretreatment of cells augmented the effects of both cytokines on carrier-mediated amino acid uptake. Dexamethasone pretreatment and a combination of IL-6 and TNF-alpha resulted in a greater than twofold increase in transport activity. Fluorescent-activated cell sorter analysis demonstrated that dexamethasone induced a threefold increase in the expression of high-affinity IL-6 receptors. CONCLUSIONS: Interleukin-6 and TNF-alpha work coordinately with glucocorticoids to stimulate amino acid uptake in human hepatocytes. Dexamethasone exerts a permissive effect on cytokine-mediated increases in transport by increasing IL

  5. Induction of cytochrome P4501A by highly purified hexachlorobenzene in primary cultures of ring-necked pheasant and Japanese quail embryo hepatocytes.

    PubMed

    Mundy, Lukas J; Crump, Doug; Jones, Stephanie P; Konstantinov, Alex; Utley, Fiona; Potter, David; Kennedy, Sean W

    2012-04-01

    Primary cultures of ring-necked pheasant (Phasianus colchicus) and Japanese quail (Coturnix japonica) embryo hepatocytes were used to compare the potencies of highly purified hexachlorobenzne (HCB-P), reagent-grade HCB (RG-HCB) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as inducers of ethoxyresorufin O-deethylase (EROD) activity, cytochrome P4501A (CYP1A4) messenger ribonucleic acid (mRNA) and CYP1A5 mRNA. HCB-P, RG-HCB and TCDD all induced EROD activity and up-regulated CYP1A4 and CYP1A5 mRNA. Induction was not caused by contamination of HCB with polychlorinated dibenzo-p-dioxins, dibenzofurans or biphenyls. Based upon a comparison of the EC(50) and EC(threshold) values for EROD and CYP1A4/5 concentration-response curves, the potency of HCB relative to TCDD was 0.001 in ring-necked pheasant and 0.01 in Japanese quail embryo hepatocytes. Differences in species sensitivity to HCB were found to be mainly dictated by differences in species sensitivity to TCDD rather than differences in the absolute potency of HCB. Consequently, ring-necked pheasant and Japanese quail embryo hepatocytes were found to be equally sensitive to HCB exposure. Species sensitivity comparisons were also made with chicken (Gallus gallus domesticus) and revealed that chicken embryo hepatocytes were less responsive to EROD induction (lower maximal response) by HCB compared to the embryo hepatocytes of pheasant and quail. PMID:22227438

  6. Hepatocytes as Immunological Agents.

    PubMed

    Crispe, Ian N

    2016-01-01

    Hepatocytes are targeted for infection by a number of major human pathogens, including hepatitis B virus, hepatitis C virus, and malaria. However, hepatocytes are also immunological agents in their own right. In systemic immunity, they are central in the acute-phase response, which floods the circulation with defensive proteins during diverse stresses, including ischemia, physical trauma, and sepsis. Hepatocytes express a variety of innate immune receptors and, when challenged with pathogen- or damage-associated molecular patterns, can deliver cell-autonomous innate immune responses that may result in host defense or in immunopathology. Important human pathogens have evolved mechanisms to subvert these responses. Finally, hepatocytes talk directly to T cells, resulting in a bias toward immune tolerance. PMID:26685314

  7. Cholangiocarcinomas can originate from hepatocytes in mice

    PubMed Central

    Fan, Biao; Malato, Yann; Calvisi, Diego F.; Naqvi, Syed; Razumilava, Nataliya; Ribback, Silvia; Gores, Gregory J.; Dombrowski, Frank; Evert, Matthias; Chen, Xin; Willenbring, Holger

    2012-01-01

    Intrahepatic cholangiocarcinomas (ICCs) are primary liver tumors with a poor prognosis. The development of effective therapies has been hampered by a limited understanding of the biology of ICCs. Although ICCs exhibit heterogeneity in location, histology, and marker expression, they are currently thought to derive invariably from the cells lining the bile ducts, biliary epithelial cells (BECs), or liver progenitor cells (LPCs). Despite lack of experimental evidence establishing BECs or LPCs as the origin of ICCs, other liver cell types have not been considered. Here we show that ICCs can originate from fully differentiated hepatocytes. Using a mouse model of hepatocyte fate tracing, we found that activated NOTCH and AKT signaling cooperate to convert normal hepatocytes into biliary cells that act as precursors of rapidly progressing, lethal ICCs. Our findings suggest a previously overlooked mechanism of human ICC formation that may be targetable for anti-ICC therapy. PMID:22797301

  8. The use of primary rat hepatocytes to achieve metabolic activation of promutagens in the Chinese hamster ovary/hypoxantine-guanine phosphoribosyl transferase mutational assay

    SciTech Connect

    Bermudez, E.; Couch, D.B.; Tillery, D.

    1982-01-01

    A method is described in which primary rat hepatocytes have been cocultured with chinese hamster ovary (CHO) cells to provide metabolic activation of promutgens in the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl transferase (CHO/HGPRT) mutational assay. Single cell hepatocyte suspensions were prepared from male Fisher-344 rats using the in situ collagenase perfusion technique. Hepatocytes were allowed to attach for 1.5 hours in tissue culture dishes containing an approximately equal number of CHO cells in log growth. The cocultures were exposed to promutagens for up to 20 hours in serum-free medium. The survival and 6-thioguanine-resistant fraction of treated CHO cells were then determined as in the standard CHO/HGPRT assay. Aflatoxin B/sub 1/ (AFB/sub 1/) 7,12-dimethylbenz(a)anthracene (DMBA) and benzo(a)pyrene (B(a)P) were found to produce increases in the mutant fractions of treated CHO cells as a function of concentration. The time required for optimum expression of the mutant phenotype following exposure to DMBA and AFB/sub 1/ was approximately 8 days. Primary cell-mediated mutagenesis may be useful in elucidating methobolic pathways important in the production and detoxification of genotoxic products in vivo.

  9. Human Immunodeficiency Virus (HIV) Primary Infection

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Human Immunodeficiency Virus (HIV) Primary Infection Information for adults A A ... weeks following exposure to HIV (the human immunodeficiency virus). Chronic infection with this virus can cause AIDS ( ...

  10. Ado-Trastuzumab Emtansine Targets Hepatocytes Via Human Epidermal Growth Factor Receptor 2 to Induce Hepatotoxicity.

    PubMed

    Yan, Haoheng; Endo, Yukinori; Shen, Yi; Rotstein, David; Dokmanovic, Milos; Mohan, Nishant; Mukhopadhyay, Partha; Gao, Bin; Pacher, Pal; Wu, Wen Jin

    2016-03-01

    Ado-trastuzumab emtansine (T-DM1) is an antibody-drug conjugate (ADC) approved for the treatment of HER2-positive metastatic breast cancer. It consists of trastuzumab, a humanized mAb directed against HER2, and a microtubule inhibitor, DM1, conjugated to trastuzumab via a thioether linker. Hepatotoxicity is one of the serious adverse events associated with T-DM1 therapy. Mechanisms underlying T-DM1-induced hepatotoxicity remain elusive. Here, we use hepatocytes and mouse models to investigate the mechanisms of T-DM1-induced hepatotoxicity. We show that T-DM1 is internalized upon binding to cell surface HER2 and is colocalized with LAMP1, resulting in DM1-associated cytotoxicity, including disorganized microtubules, nuclear fragmentation/multiple nuclei, and cell growth inhibition. We further demonstrate that T-DM1 treatment significantly increases the serum levels of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in mice and induces inflammation and necrosis in liver tissues, and that T-DM1-induced hepatotoxicity is dose dependent. Moreover, the gene expression of TNFα in liver tissues is significantly increased in mice treated with T-DM1 as compared with those treated with trastuzumab or vehicle. We propose that T-DM1-induced upregulation of TNFα enhances the liver injury that may be initially caused by DM1-mediated intracellular damage. Our proposal is underscored by the fact that T-DM1 induces the outer mitochondrial membrane rupture, a typical morphologic change in the mitochondrial-dependent apoptosis, and mitochondrial membrane potential dysfunction. Our work provides mechanistic insights into T-DM1-induced hepatotoxicity, which may yield novel strategies to manage liver injury induced by T-DM1 or other ADCs. PMID:26712117

  11. In vitro evaluation of hepatotoxic drugs in human hepatocytes from multiple donors: Identification of P450 activity as a potential risk factor for drug-induced liver injuries.

    PubMed

    Utkarsh, Doshi; Loretz, Carol; Li, Albert P

    2016-08-01

    A possible risk factor for drug-induced hepatotoxicity is drug metabolizing enzyme activity, which is known to vary among individuals due to genetic (genetic polymorphism) and environmental factors (environmental pollutants, foods, and medications that are inhibitors or inducers of drug metabolizing enzymes). We hypothesize that hepatic cytochrome P450-dependent monooxygenase (CYP) activity is one of the key risk factors for drug induced liver injuries (DILI) in the human population, especially for drugs that are metabolically activated to cytotoxic/reactive metabolites. Human hepatocytes from 19 donors were evaluated for the activities of 8 major P450 isoforms: CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4. Extensive individual variations were observed, consistent with what is known to be in the human population. As CYP3A4 is known to be one of the most important P450 isoforms for drug metabolism, studies were performed to evaluate the relationship between the in vitro cytotoxicity of hepatotoxic drugs and CYP3A4 activity. In a proof of concept study, hepatocytes from six donors (lots) representing the observed range of CYP3A4 activities were chosen for the evaluation of in vitro hepatotoxicity of four drugs known to be associated with acute liver failure: acetaminophen, cyclophosphamide, ketoconazole, and tamoxifen. The hepatocytes were cultured in collagen-coated plates and treated with the hepatotoxicants for approximately 24 h, followed by viability determination based on cellular adenosine triphosphate (ATP) contents. HH1023, the lot of hepatocytes with the highest CYP3A4 activity, was found to be the most sensitive to the cytotoxicity of all 4 hepatotoxic drugs, thereby suggesting that high CYP3A4 activity may be a risk factor. To further validate the relationship, a second study was performed with hepatocytes from 16 donors. In this study, the hepatocytes were quantified for CYP3A4 activity at the time of treatment. Results of the

  12. The regulation of cytoskeletal and liver-specific gene expression during liver regeneration and primary hepatocyte culture

    SciTech Connect

    Robinson, G.S.

    1989-01-01

    The focus of this dissertation is to determine what role(s) the extracellular matrix and expression of certain cytoskeletal genes play in the regulation of hepatocyte growth and the maintenance of a differential state. The expression of several cytoskeletal and liver-specific genes was examined during liver regeneration and in hepatocyte cultures maintained in a hormonally-defined, serum-free medium and plated on two different matrices: rat tail collagen and the EHS matrix. During liver regeneration and in hepatocytes cultured on rat tail collagen, there was a dramatic increase in tubulin mRNA levels coincident with but not linked to DNA synthesis. The message levels for other cytoskeletal genes similarly increased, while a decrease was observed in the mRNA levels of the liver-specific genes, serum albumin and alpha{sub 1} inhibitor III. Hepatocytes cultured on the EHS matrix resulted in the maintenance of low levels of cytoskeletal gene expression and high levels of liver-specific gene expression, similar to that observed in the normal liver. Results from subcellar fractionation and two-dimensional gel electrophoresis of {sup 35}S-labelled proteins paralleled the results seen at the mRNA level. Preliminary work suggests that microtubule organization may play a role in the expression of the liver-specific genes which encode secreted proteins. These studies, which compare hepatocytes cultured on collagen or the EHS matrix gel, reveal that both cell-cell and cell-matrix interactions play a major role in the maintenance of the differential phenotype in hepatocytes.

  13. Thrombospondin-related adhesive protein (TRAP) of Plasmodium falciparum: expression during sporozoite ontogeny and binding to human hepatocytes.

    PubMed Central

    Robson, K J; Frevert, U; Reckmann, I; Cowan, G; Beier, J; Scragg, I G; Takehara, K; Bishop, D H; Pradel, G; Sinden, R

    1995-01-01

    Plasmodium sporozoites collected from oocysts, haemocoel and salivary glands of the mosquito show profound differences in their biological properties such as motility, ability to induce protective immune response and infectivity for vertebrate host cells. Sporozoites from salivary glands are much more infectious than those from oocysts and haemocoel. Differential expression of proteins, such as the circumsporozoite (CS) protein and the thrombospondin-related adhesive protein (TRAP), implicated in sporozoite recognition and entry into hepatocytes may account for the development of infectivity during ontogeny. We have carried out a series of experiments to: (i) analyse the expression and localization of TRAP in P.falciparum sporozoites during development in the mosquito; and (ii) elucidate the biochemical and adhesive properties of recombinant TRAP. Our data indicate that TRAP is not expressed in oocysts, whereas variable amounts of CS protein are found in this parasite developmental stage. Hemocoel sporozoites display the distinct phenotypes TRAP- CS protein+ and TRAP+ CS protein+ at a frequency of 98.5 and 1.5% respectively. Salivary gland sporozoites are all TRAP+ CS protein+. We also provide experimental evidence showing that recombinant TRAP binds to the basolateral cell membrane of hepatocytes in the Disse's space and that sulfated glycoconjugates function as TRAP ligands on human hepatocytes. Images PMID:7664729

  14. Interaction of ApoA-IV with NR4A1 and NR1D1 Represses G6Pase and PEPCK Transcription: Nuclear Receptor-Mediated Downregulation of Hepatic Gluconeogenesis in Mice and a Human Hepatocyte Cell Line

    PubMed Central

    Li, Xiaoming; Xu, Min; Wang, Fei; Ji, Yong; DavidsoN, W. Sean; Li, Zongfang; Tso, Patrick

    2015-01-01

    We have previously shown that the nuclear receptor, NR1D1, is a cofactor in ApoA-IV-mediated downregulation of gluconeogenesis. Nuclear receptor, NR4A1, is involved in the transcriptional regulation of various genes involved in inflammation, apoptosis, and glucose metabolism. We investigated whether NR4A1 influences the effect of ApoA-IV on hepatic glucose metabolism. Our in situ proximity ligation assays and coimmunoprecipitation experiments indicated that ApoA-IV colocalized with NR4A1 in human liver (HepG2) and kidney (HEK-293) cell lines. The chromatin immunoprecipitation experiments and luciferase reporter assays indicated that the ApoA-IV and NR4A1 colocalized at the RORα response element of the human G6Pase promoter, reducing its transcriptional activity. Our RNA interference experiments showed that knocking down the expression of NR4A1 in primary mouse hepatocytes treated with ApoA-IV increased the expression of NR1D1, G6Pase, and PEPCK, and that knocking down NR1D1 expression increased the level of NR4A1. We also found that ApoA-IV induced the expression of endogenous NR4A1 in both cultured primary mouse hepatocytes and in the mouse liver, and decreased glucose production in primary mouse hepatocytes. Our findings showed that ApoA-IV colocalizes with NR4A1, which suppresses G6Pase and PEPCK gene expression at the transcriptional level, reducing hepatic glucose output and lowering blood glucose. The ApoA-IV-induced increase in NR4A1 expression in hepatocytes mediates further repression of gluconeogenesis. Our findings suggest that NR1D1 and NR4A1 serve similar or complementary functions in the ApoA-IV-mediated regulation of gluconeogenesis. PMID:26556724

  15. Inhibition of preS1-hepatocyte interaction by an array of recombinant human antibodies from naturally recovered individuals

    PubMed Central

    Sankhyan, Anurag; Sharma, Chandresh; Dutta, Durgashree; Sharma, Tarang; Chosdol, Kunzang; Wakita, Takaji; Watashi, Koichi; Awasthi, Amit; Acharya, Subrat K.; Khanna, Navin; Tiwari, Ashutosh; Sinha, Subrata

    2016-01-01

    Neutralizing monoclonal antibodies are being found to be increasingly useful in viral infections. In hepatitis B infection, antibodies are proven to be useful for passive prophylaxis. The preS1 region (21–47a.a.) of HBV contains the viral hepatocyte-binding domain crucial for its attachment and infection of hepatocytes. Antibodies against this region are neutralizing and are best suited for immune-based neutralization of HBV, especially in view of their not recognizing decoy particles. Anti-preS1 (21–47a.a.) antibodies are present in serum of spontaneously recovered individuals. We generated a phage-displayed scFv library using circulating lymphocytes from these individuals and selected four preS1-peptide specific scFvs with markedly distinct sequences from this library. All the antibodies recognized the blood-derived and recombinant preS1 containing antigens. Each scFv showed a discrete binding signature, interacting with different amino acids within the preS1-peptide region. Ability to prevent binding of the preS1 protein (N-terminus 60a.a.) to HepG2 cells stably expressing hNTCP (HepG2-hNTCP-C4 cells), the HBV receptor on human hepatocytes was taken as a surrogate marker for neutralizing capacity. These antibodies inhibited preS1-hepatocyte interaction individually and even better in combination. Such a combination of potentially neutralizing recombinant antibodies with defined specificities could be used for preventing/managing HBV infections, including those by possible escape mutants. PMID:26888694

  16. Scalable Differentiation of Human iPSCs in a Multicellular Spheroid-based 3D Culture into Hepatocyte-like Cells through Direct Wnt/β-catenin Pathway Inhibition.

    PubMed

    Pettinato, Giuseppe; Ramanathan, Rajesh; Fisher, Robert A; Mangino, Martin J; Zhang, Ning; Wen, Xuejun

    2016-01-01

    Treatment of acute liver failure by cell transplantation is hindered by a shortage of human hepatocytes. Current protocols for hepatic differentiation of human induced pluripotent stem cells (hiPSCs) result in low yields, cellular heterogeneity, and limited scalability. In the present study, we have developed a novel multicellular spheroid-based hepatic differentiation protocol starting from embryoid bodies of hiPSCs (hiPSC-EBs) for robust mass production of human hepatocyte-like cells (HLCs) using two novel inhibitors of the Wnt pathway. The resultant hiPSC-EB-HLCs expressed liver-specific genes, secreted hepatic proteins such as Albumin, Alpha Fetoprotein, and Fibrinogen, metabolized ammonia, and displayed cytochrome P450 activities and functional activities typical of mature primary hepatocytes, such as LDL storage and uptake, ICG uptake and release, and glycogen storage. Cell transplantation of hiPSC-EB-HLC in a rat model of acute liver failure significantly prolonged the mean survival time and resolved the liver injury when compared to the no-transplantation control animals. The transplanted hiPSC-EB-HLCs secreted human albumin into the host plasma throughout the examination period (2 weeks). Transplantation successfully bridged the animals through the critical period for survival after acute liver failure, providing promising clues of integration and full in vivo functionality of these cells after treatment with WIF-1 and DKK-1. PMID:27616299

  17. Hepatitis C Virus Infection Suppresses the Interferon Response in the Liver of the Human Hepatocyte Chimeric Mouse

    PubMed Central

    Tsuge, Masataka; Fujimoto, Yoshifumi; Hiraga, Nobuhiko; Zhang, Yizhou; Ohnishi, Mayu; Kohno, Tomohiko; Abe, Hiromi; Miki, Daiki; Imamura, Michio; Takahashi, Shoichi; Ochi, Hidenori; Hayes, C. Nelson; Miya, Fuyuki; Tsunoda, Tatsuhiko; Chayama, Kazuaki

    2011-01-01

    Background and Aims Recent studies indicate that hepatitis C virus (HCV) can modulate the expression of various genes including those involved in interferon signaling, and up-regulation of interferon-stimulated genes by HCV was reported to be strongly associated with treatment outcome. To expand our understanding of the molecular mechanism underlying treatment resistance, we analyzed the direct effects of interferon and/or HCV infection under immunodeficient conditions using cDNA microarray analysis of human hepatocyte chimeric mice. Methods Human serum containing HCV genotype 1b was injected into human hepatocyte chimeric mice. IFN-α was administered 8 weeks after inoculation, and 6 hours later human hepatocytes in the mouse livers were collected for microarray analysis. Results HCV infection induced a more than 3-fold change in the expression of 181 genes, especially genes related to Organismal Injury and Abnormalities, such as fibrosis or injury of the liver (P = 5.90E-16 ∼ 3.66E-03). IFN administration induced more than 3-fold up-regulation in the expression of 152 genes. Marked induction was observed in the anti-fibrotic chemokines such as CXCL9, suggesting that IFN treatment might lead not only to HCV eradication but also prevention and repair of liver fibrosis. HCV infection appeared to suppress interferon signaling via significant reduction in interferon-induced gene expression in several genes of the IFN signaling pathway, including Mx1, STAT1, and several members of the CXCL and IFI families (P = 6.0E-12). Genes associated with Antimicrobial Response and Inflammatory Response were also significantly repressed (P = 5.22×10−10 ∼ 1.95×10−2). Conclusions These results provide molecular insights into possible mechanisms used by HCV to evade innate immune responses, as well as novel therapeutic targets and a potential new indication for interferon therapy. PMID:21886832

  18. Mechanisms of lysophosphatidylcholine-induced hepatocyte lipoapoptosis

    PubMed Central

    Kakisaka, Keisuke; Cazanave, Sophie C.; Fingas, Christian D.; Guicciardi, Maria E.; Bronk, Steven F.; Werneburg, Nathan W.; Mott, Justin L.

    2012-01-01

    Isolated hepatocytes undergo lipoapoptosis, a feature of hepatic lipotoxicity, on treatment with saturated free fatty acids (FFA) such as palmitate (PA). However, it is unknown if palmitate is directly toxic to hepatocytes or if its toxicity is indirect via the generation of lipid metabolites such as lysophosphatidylcholine (LPC). PA-mediated hepatocyte lipoapoptosis is associated with endoplasmic reticulum (ER) stress, c-Jun NH2-terminal kinase (JNK) activation, and a JNK-dependent upregulation of the potent proapoptotic BH3-only protein PUMA (p53 upregulated modulator of apoptosis). Our aim was to determine which of these mechanisms of lipotoxicity are activated by PA-derived LPC. We employed Huh-7 cells and isolated murine and human primary hepatocytes. Intracellular LPC concentrations increase linearly as a function of the exogenous, extracellular PA, stearate, or LPC concentration. Incubation of Huh-7 cells or primary hepatocytes with LPC induced cell death by apoptosis in a concentration-dependent manner. Substituting LPC for PA resulted in caspase-dependent cell death that was accompanied by activating phosphorylation of JNK with c-Jun phosphorylation and an increase in PUMA expression. LPC also induced ER stress as manifest by eIF2α phosphorylation and CAAT/enhancer binding homologous protein (CHOP) induction. LPC cytotoxicity was attenuated by pharmacological inhibition of JNK or glycogen synthase kinase-3 (GSK-3). Similarly, short-hairpin RNA (shRNA)-targeted knockdown of CHOP protected Huh-7 cells against LPC-induced toxicity. The LPC-induced PUMA upregulation was prevented by JNK inhibition or shRNA-targeted knockdown of CHOP. Finally, genetic deficiency of PUMA rendered murine hepatocytes resistant to LPC-induced apoptosis. We concluded that LPC-induced lipoapoptosis is dependent on mechanisms largely indistinguishable from PA. These data suggest that FFA-mediated cytotoxicity is indirect via the generation of the toxic metabolite, LPC. PMID:21995961

  19. A physiologically based biodynamic (PBBD) model for estragole DNA binding in rat liver based on in vitro kinetic data and estragole DNA adduct formation in primary hepatocytes

    SciTech Connect

    Paini, Alicia; Punt, Ans; Viton, Florian; Scholz, Gabriele; Delatour, Thierry; Marin-Kuan, Maricel; Schilter, Benoit; Bladeren, Peter J. van; Rietjens, Ivonne M.C.M.

    2010-05-15

    Estragole has been shown to be hepatocarcinogenic in rodent species at high-dose levels. Translation of these results into the likelihood of formation of DNA adducts, mutation, and ultimately cancer upon more realistic low-dose exposures remains a challenge. Recently we have developed physiologically based biokinetic (PBBK) models for rat and human predicting bioactivation of estragole. These PBBK models, however, predict only kinetic characteristics. The present study describes the extension of the PBBK model to a so-called physiologically based biodynamic (PBBD) model predicting in vivo DNA adduct formation of estragole in rat liver. This PBBD model was developed using in vitro data on DNA adduct formation in rat primary hepatocytes exposed to 1'-hydroxyestragole. The model was extended by linking the area under the curve for 1'-hydroxyestragole formation predicted by the PBBK model to the area under the curve for 1'-hydroxyestragole in the in vitro experiments. The outcome of the PBBD model revealed a linear increase in DNA adduct formation with increasing estragole doses up to 100 mg/kg bw. Although DNA adduct formation of genotoxic carcinogens is generally seen as a biomarker of exposure rather than a biomarker of response, the PBBD model now developed is one step closer to the ultimate toxic effect of estragole than the PBBK model described previously. Comparison of the PBBD model outcome to available data showed that the model adequately predicts the dose-dependent level of DNA adduct formation. The PBBD model predicts DNA adduct formation at low levels of exposure up to a dose level showing to cause cancer in rodent bioassays, providing a proof of principle for modeling a toxicodynamic in vivo endpoint on the basis of solely in vitro experimental data.

  20. Effect of diphenyl ether herbicides and oxadiazon on porphyrin biosynthesis in mouse liver, rat primary hepatocyte culture and HepG2 cells.

    PubMed

    Krijt, J; van Holsteijn, I; Hassing, I; Vokurka, M; Blaauboer, B J

    1993-01-01

    The effects of the herbicides fomesafen, oxyfluorfen, oxadiazon and fluazifop-butyl on porphyrin accumulation in mouse liver, rat primary hepatocyte culture and HepG2 cells were investigated. Ten days of herbicide feeding (0.25% in the diet) increased the liver porphyrins in male C57B1/6J mice from 1.4 +/- 0.6 to 4.8 +/- 2.1 (fomesafen) 16.9 +2- 2.9 (oxyfluorfen) and 25.9 +/- 3.1 (oxadiazon) nmol/g wet weight, respectively. Fluazifop-butyl had no effect on liver porphyrin metabolism. Fomesafen, oxyfluorfen and oxadiazon increased the cellular porphyrin content of rat hepatocytes after 24 h of incubation (control, 3.2 pmol/mg protein, fomesafen, oxyfluorfen and oxadiazon at 0.125 mM concentration 51.5, 54.3 and 44.0 pmol/mg protein, respectively). The porphyrin content of HepG2 cells increased from 1.6 to 18.2, 10.6 and 9.2 pmol/mg protein after 24 h incubation with the three herbicides. Fluazifop-butyl increased hepatic cytochrome P450 levels and ethoxy- and pentoxyresorufin O-dealkylase (EROD and PROD) activity, oxyfluorfen increased PROD activity. Peroxisomal palmitoyl CoA oxidation increased after fomesafen and fluazifop treatment to about 500% of control values both in mouse liver and rat hepatocytes. Both rat hepatocytes and HepG2 cells can be used as a test system for the porphyrogenic potential of photobleaching herbicides. PMID:8517781

  1. Evaluating microRNA profiles reveals discriminative responses following genotoxic or non-genotoxic carcinogen exposure in primary mouse hepatocytes.

    PubMed

    Rieswijk, Linda; Brauers, Karen J J; Coonen, Maarten L J; van Breda, Simone G J; Jennen, Danyel G J; Kleinjans, Jos C S

    2015-11-01

    Chemical carcinogenesis can be induced by genotoxic (GTX) or non-genotoxic (NGTX) carcinogens. GTX carcinogens have a well-described mode of action. However, the complex mechanisms by which NGTX carcinogens act are less clear and may result in conflicting results between species [e.g. Wy-14,643 (Wy)]. We hypothesise that common microRNA response pathways exist for each class of carcinogenic agents. Therefore, this study compares and integrates mRNA and microRNA expression profiles following short term acute exposure (24 and 48h) to three GTX [aflatoxin B1 (AFB1), benzo[a]pyrene (BaP) and cisplatin (CisPl)] or three NGTX (2,3,7,8-tetrachloordibenzodioxine (TCDD), cyclosporine A (CsA) and Wy) carcinogens in primary mouse hepatocytes. Discriminative gene sets, microRNAs (not for 24h) and processes were identified following 24 and 48h of exposure. From the three discriminative microRNAs found following 48h of exposure, mmu-miR-503-5p revealed to have an interaction with mRNA target gene cyclin D2 (Ccnd2 - 12444) which was involved in the discriminative process of p53 signalling and metabolism. Following exposure to NGTX carcinogens Mmu-miR-503-5p may have an oncogenic function by stimulating Ccnd2 possibly leading to a tumourigenic cell cycle progression. By contrast, after GTX carcinogen exposure it may have a tumour-suppressive function (repressing Ccnd2) leading to cell cycle arrest and to increased DNA repair activities. In addition, compound-specific microRNA-mRNA interactions [mmu-miR-301b-3p-Papss2 (for AFB1), as well as mmu-miR-29b-3p-Col4a2 and mmu-miR-24-3p-Flna (for BaP)] were found to contribute to a better understanding of microRNAs in cell cycle arrest and the impairment of the DNA damage repair, an important hallmark of GTX-induced carcinogenesis. Overall, our results indicate that microRNAs represent yet another relevant intracellular regulatory level in chemical carcinogenesis. PMID:25976910

  2. Mechanistic pharmacokinetic modeling for the prediction of transporter-mediated disposition in humans from sandwich culture human hepatocyte data.

    PubMed

    Jones, Hannah M; Barton, Hugh A; Lai, Yurong; Bi, Yi-An; Kimoto, Emi; Kempshall, Sarah; Tate, Sonya C; El-Kattan, Ayman; Houston, J Brian; Galetin, Aleksandra; Fenner, Katherine S

    2012-05-01

    With efforts to reduce cytochrome P450-mediated clearance (CL) during the early stages of drug discovery, transporter-mediated CL mechanisms are becoming more prevalent. However, the prediction of plasma concentration-time profiles for such compounds using physiologically based pharmacokinetic (PBPK) modeling is far less established in comparison with that for compounds with passively mediated pharmacokinetics (PK). In this study, we have assessed the predictability of human PK for seven organic anion-transporting polypeptide (OATP) substrates (pravastatin, cerivastatin, bosentan, fluvastatin, rosuvastatin, valsartan, and repaglinide) for which clinical intravenous data were available. In vitro data generated from the sandwich culture human hepatocyte system were simultaneously fit to estimate parameters describing both uptake and biliary efflux. Use of scaled active uptake, passive distribution, and biliary efflux parameters as inputs into a PBPK model resulted in the overprediction of exposure for all seven drugs investigated, with the exception of pravastatin. Therefore, fitting of in vivo data for each individual drug in the dataset was performed to establish empirical scaling factors to accurately capture their plasma concentration-time profiles. Overall, active uptake and biliary efflux were under- and overpredicted, leading to average empirical scaling factors of 58 and 0.061, respectively; passive diffusion required no scaling factor. This study illustrates the mechanistic and model-driven application of in vitro uptake and efflux data for human PK prediction for OATP substrates. A particular advantage is the ability to capture the multiphasic plasma concentration-time profiles for such compounds using only preclinical data. A prediction strategy for novel OATP substrates is discussed. PMID:22344703

  3. Formation of GSH-trapped reactive metabolites in human liver microsomes, S9 fraction, HepaRG-cells, and human hepatocytes.

    PubMed

    Lassila, Toni; Rousu, Timo; Mattila, Sampo; Chesné, Christophe; Pelkonen, Olavi; Turpeinen, Miia; Tolonen, Ari

    2015-11-10

    The objective was to compare several in vitro human liver-derived subcellular and cellular incubation systems for the formation of GSH-trapped reactive metabolites. Incubations of pooled human liver microsomes, human liver S9 fractions, HepaRG-cells, and human hepatocytes were performed with glutathione as a trapping agent. Experiments with liver S9 were performed under two conditions, using only NADPH and using a full set of cofactors enabling also conjugative metabolism. Ten structurally different compounds were used as a test set, chosen as either "positive" (ciprofloxacin, clozapine, diclofenac, ethinyl estradiol, pulegone, and ticlopidine) or "negative" (caffeine, citalopram, losartan, montelukast) compounds, based on their known adverse reactions on liver or bone marrow. GSH conjugates were observed for seven of the ten compounds; while no conjugates were observed for caffeine, citalopram, or ciprofloxacin. Hepatocyte and HepaRG assays produced a clearly lower number and lower relative abundance of GSH conjugates compared to assays with microsomes and S9 fractions. The major GSH conjugates were different for many compounds in cellular subfractions and cell-based systems. Hepatocytes generally produced a higher number of GSH conjugates than HepaRG cells, although the differences were minor. The results show that the hepatic enzyme system used for screening of GSH-trapped reactive metabolites do have a high impact on the results, and results between different systems are comparable only qualitatively. PMID:26263063

  4. Fluid shear stress modulation of hepatocyte-like cell function.

    PubMed

    Rashidi, Hassan; Alhaque, Sharmin; Szkolnicka, Dagmara; Flint, Oliver; Hay, David C

    2016-07-01

    Freshly isolated human adult hepatocytes are considered to be the gold standard tool for in vitro studies. However, primary hepatocyte scarcity, cell cycle arrest and the rapid loss of cell phenotype limit their widespread deployment. Human embryonic stem cells and induced pluripotent stem cells provide renewable sources of hepatocyte-like cells (HLCs). Despite the use of various differentiation methodologies, HLCs like primary human hepatocytes exhibit unstable phenotype in culture. It has been shown that the functional capacity can be improved by adding back elements of human physiology, such as cell co-culture or through the use of natural and/or synthetic surfaces. In this study, the effect of fluid shear stress on HLC performance was investigated. We studied two important liver functions, cytochrome P450 drug metabolism and serum protein secretion, in static cultures and those exposed to fluid shear stress. Our study demonstrates that fluid shear stress improved Cyp1A2 activity by approximately fivefold. This was paralleled by an approximate ninefold increase in sensitivity to a drug, primarily metabolised by Cyp2D6. In addition to metabolic capacity, fluid shear stress also improved hepatocyte phenotype with an approximate fourfold reduction in the secretion of a foetal marker, alpha-fetoprotein. We believe these studies highlight the importance of introducing physiologic cues in cell-based models to improve somatic cell phenotype. PMID:26979076

  5. Mechanistic Modeling of Pitavastatin Disposition in Sandwich-Cultured Human Hepatocytes: A Proteomics-Informed Bottom-Up Approach.

    PubMed

    Vildhede, Anna; Mateus, André; Khan, Elin K; Lai, Yurong; Karlgren, Maria; Artursson, Per; Kjellsson, Maria C

    2016-04-01

    Isolated human hepatocytes are commonly used to predict transporter-mediated clearance in vivo. Such predictions, however, do not provide estimations of transporter contributions and consequently do not allow predictions of the outcome resulting from a change in the activity of a certain transporter, for example, by inhibition or a genetic variant with reduced function. Pitavastatin is a drug that is heavily dependent on hepatic transporters for its elimination, and it is excreted mainly as unchanged drug in the bile. For this reason, pitavastatin was used as a model drug to demonstrate the applicability of a bottom-up approach to predict transporter-mediated disposition in sandwich-cultured human hepatocytes (SCHHs), allowing for the estimation of transporter contributions. Transport experiments in transfected human embryonic kidney cells (HEK293 cell lines) and inverted membrane vesicles overexpressing each of the relevant transport proteins were used to generate parameter estimates for the mechanistic model. By adjusting for differences in transporter abundance between the in vitro systems and individual SCHH batches, the model successfully predicted time profiles of medium and intracellular accumulation. Our predictions of pitavastatin bile accumulation could not be confirmed, however, because of a very low biliary excretion of pitavastatin in relation to the hepatic uptake in our SCHHs. This study is, to our knowledge, the first to successfully simulate transporter-mediated processes in a complex system such as SCHHs at the level of individual transport proteins using a bottom-up approach. PMID:26842596

  6. Improved survival of porcine acute liver failure by a bioartificial liver device implanted with induced human functional hepatocytes.

    PubMed

    Shi, Xiao-Lei; Gao, Yimeng; Yan, Yupeng; Ma, Hucheng; Sun, Lulu; Huang, Pengyu; Ni, Xuan; Zhang, Ludi; Zhao, Xin; Ren, Haozhen; Hu, Dan; Zhou, Yan; Tian, Feng; Ji, Yuan; Cheng, Xin; Pan, Guoyu; Ding, Yi-Tao; Hui, Lijian

    2016-02-01

    Acute liver failure (ALF) is a life-threatening illness. The extracorporeal cell-based bioartificial liver (BAL) system could bridge liver transplantation and facilitate liver regeneration for ALF patients by providing metabolic detoxification and synthetic functions. Previous BAL systems, based on hepatoma cells and non-human hepatocytes, achieved limited clinical advances, largely due to poor hepatic functions, cumbersome preparation or safety concerns of these cells. We previously generated human functional hepatocytes by lineage conversion (hiHeps). Here, by improving functional maturity of hiHeps and producing hiHeps at clinical scales (3 billion cells), we developed a hiHep-based BAL system (hiHep-BAL). In a porcine ALF model, hiHep-BAL treatment restored liver functions, corrected blood levels of ammonia and bilirubin, and prolonged survival. Importantly, human albumin and α-1-antitrypsin were detectable in hiHep-BAL-treated ALF pigs. Moreover, hiHep-BAL treatment led to attenuated liver damage, resolved inflammation and enhanced liver regeneration. Our findings indicate a promising clinical application of the hiHep-BAL system. PMID:26768767

  7. Improved survival of porcine acute liver failure by a bioartificial liver device implanted with induced human functional hepatocytes

    PubMed Central

    Shi, Xiao-Lei; Gao, Yimeng; Yan, Yupeng; Ma, Hucheng; Sun, Lulu; Huang, Pengyu; Ni, Xuan; Zhang, Ludi; Zhao, Xin; Ren, Haozhen; Hu, Dan; Zhou, Yan; Tian, Feng; Ji, Yuan; Cheng, Xin; Pan, Guoyu; Ding, Yi-Tao; Hui, Lijian

    2016-01-01

    Acute liver failure (ALF) is a life-threatening illness. The extracorporeal cell-based bioartificial liver (BAL) system could bridge liver transplantation and facilitate liver regeneration for ALF patients by providing metabolic detoxification and synthetic functions. Previous BAL systems, based on hepatoma cells and non-human hepatocytes, achieved limited clinical advances, largely due to poor hepatic functions, cumbersome preparation or safety concerns of these cells. We previously generated human functional hepatocytes by lineage conversion (hiHeps). Here, by improving functional maturity of hiHeps and producing hiHeps at clinical scales (3 billion cells), we developed a hiHep-based BAL system (hiHep-BAL). In a porcine ALF model, hiHep-BAL treatment restored liver functions, corrected blood levels of ammonia and bilirubin, and prolonged survival. Importantly, human albumin and α-1-antitrypsin were detectable in hiHep-BAL-treated ALF pigs. Moreover, hiHep-BAL treatment led to attenuated liver damage, resolved inflammation and enhanced liver regeneration. Our findings indicate a promising clinical application of the hiHep-BAL system. PMID:26768767

  8. Insulin resistance in uremia. Characterization of lipid metabolism in freshly isolated and primary cultures of hepatocytes from chronic uremic rats.

    PubMed Central

    Caro, J F; Lanza-Jacoby, S

    1983-01-01

    We have studied the mechanism(s) of hyperlipidemia and liver insulin sensitivity in a rat model of severe chronic uremia (U). Basal lipid synthesis was decreased in freshly isolated hepatocytes from U when compared with sham-operated ad lib.-fed controls (alfC). Basal lipid synthesis in pair-fed controls (pfC) was in between U and alfC. Similarly, the activity of liver acetyl CoA carboxylase, fatty acid synthetase, citrate cleavage enzyme, malate dehydrogenase, and glucose-6-phosphate dehydrogenase was diminished in U. Muscle and adipose tissue lipoprotein lipase was also decreased. Insulin stimulated lipid synthesis in freshly isolated hepatocytes from alfC. Hepatocytes from U and pfC were resistant to this effect of insulin. To ascertain if the insulin resistance in U was due to starvation (chow intake 50% of alfC) or to uremia itself, the U and pfC were intragastrically fed an isocaloric diet via a Holter pump the last week of the experimental period. Hepatocytes from orally fed U and pfC were also cultured for 24 h in serum-free medium. While freshly isolated and cultured U hepatocytes remained insulin resistant, those from pfC normalized, in vivo and in vitro, when they were provided with enough nutrients. Conclusions: (a) Hyperlipidemia in uremia is not due to increased synthesis, but to defect(s) in clearance. (b) Insulin does not stimulate lipid synthesis in uremia. This finding, along with our recent demonstration that insulin binding and internalization are not decreased in the uremic liver, suggests that a post-binding defect(s) in the liver plays an important role in the mechanism(s) of insulin resistance in uremia. (c) Cultured hepatocytes from uremic rats remain insulin resistant. This quality renders these cells useful in studying the postinsulin binding events responsible for the insulin-resistant state in the absence of complicating hormonal and substrate changes that occur in vivo. PMID:6350367

  9. Human neonatal hepatocyte transplantation induces long-term rescue of unconjugated hyperbilirubinemia in the Gunn rat.

    PubMed

    Tolosa, Laia; López, Silvia; Pareja, Eugenia; Donato, María Teresa; Myara, Anne; Nguyen, Tuan Huy; Castell, José Vicente; Gómez-Lechón, María José

    2015-06-01

    Crigler-Najjar type 1 disease is a rare inherited metabolic disease characterized by high levels of unconjugated bilirubin due to the complete absence of hepatic uridine diphosphoglucuronate-glucuronosyltransferase activity. Hepatocyte transplantation (HT) has been proposed as an alternative treatment for Crigler-Najjar syndrome, but it is still limited by the quality and the low engraftment and repopulation ability of the cells used. Because of their attachment capability and expression of adhesion molecules as well as the higher proportion of hepatic progenitor cells, neonatal hepatocytes may have an advantage over adult cells. Adult or neonatal hepatocytes were transplanted into Gunn rats, a model for Crigler-Najjar disease. Engraftment and repopulation were studied and compared by immunofluorescence (IF). Additionally, the serum bilirubin levels, the presence of bilirubin conjugates in rat serum, and the expression of uridine diphosphate glucuronosyltransferase 1 family polypeptide A1 (UGT1A1) in rat liver samples were also analyzed. Here we show that neonatal HT results in long-term correction in Gunn rats. In comparison with adult cells, neonatal cells showed better engraftment and repopulation capability 3 days and 6 months after transplantation, respectively. Bilirubinemia decreased in the transplanted animals during the whole experimental follow-up (6 months). Bilirubin conjugates were also present in the serum of the transplanted animals. Western blots and IF confirmed the presence and expression of UGT1A1 in the liver. This work is the first to demonstrate the advantage of using neonatal hepatocytes for the treatment of Crigler-Najjar in vivo. PMID:25821167

  10. Ginkgolide A contributes to the potentiation of acetaminophen toxicity by Ginkgo biloba extract in primary cultures of rat hepatocytes

    SciTech Connect

    Rajaraman, Ganesh; Chen, Jie; Chang, Thomas K.H. . E-mail: tchang@interchange.ubc.ca

    2006-12-01

    The present cell culture study investigated the effect of Ginkgo biloba extract pretreatment on acetaminophen toxicity and assessed the role of ginkgolide A and cytochrome P450 3A (CYP3A) in hepatocytes isolated from adult male Long-Evans rats provided ad libitum with a standard diet. Acetaminophen (7.5-25 mM for 24 h) conferred hepatocyte toxicity, as determined by the lactate dehydrogenase (LDH) assay. G. biloba extract alone increased LDH leakage in hepatocytes at concentrations {>=} 75 {mu}g/ml and {>=} 750 {mu}g/ml after a 72 h and 24 h treatment period, respectively. G. biloba extract (25 or 50 {mu}g/ml once every 24 h for 72 h) potentiated LDH leakage by acetaminophen (10 mM for 24 h; added at 48 h after initiation of extract pretreatment). The effect was confirmed by a decrease in [{sup 14}C]-leucine incorporation. At the level present in a modulating concentration (50 {mu}g/ml) of the extract, ginkgolide A (0.55 {mu}g/ml), which increased CYP3A23 mRNA levels and CYP3A-mediated enzyme activity, accounted for part but not all of the potentiating effect of the extract on acetaminophen toxicity. This occurred as a result of CYP3A induction by ginkgolide A because triacetyloleandomycin (TAO), a specific inhibitor of CYP3A catalytic activity, completely blocked the effect of ginkgolide A. Ginkgolide B, ginkgolide C, ginkgolide J, quercetin, kaempferol, isorhamnetin, and isorhamnetin-3-O-rutinoside did not alter the extent of LDH leakage by acetaminophen. In summary, G. biloba pretreatment potentiated acetaminophen toxicity in cultured rat hepatocytes and ginkgolide A contributed to this novel effect of the extract by inducing CYP3A.

  11. The carbocyclic analog of 2'-deoxyguanosine induces a prolonged inhibition of duck hepatitis B virus DNA synthesis in primary hepatocyte cultures and in the liver.

    PubMed Central

    Fourel, I; Saputelli, J; Schaffer, P; Mason, W S

    1994-01-01

    The carbocyclic analog of 2'-deoxyguanosine (2'-CDG) is a strong inhibitor of hepatitis B virus (HBV) DNA synthesis in HepG2 cells (P.M. Price, R. Banerjee, and G. Acs, Proc. Natl. Acad. USA 86:8543-8544, 1989). We now report that 2'-CDG inhibited duck hepatitis B virus (DHBV) DNA synthesis in primary cultures of duck hepatocytes and in experimentally infected ducks. Like foscarnet (phosphonoformic acid [PFA]) and 2'-,3'-dideoxycytidine (ddC), 2'-CDG blocked viral DNA replication in primary hepatocyte cultures when present during an infection but failed to inhibit the DNA repair reaction that occurs during the initiation of infection to convert virion relaxed circular DNA to covalently closed circular DNA, the template for viral mRNA transcription. Moreover, as for PFA and ddC, viral RNA synthesis was detected when infection was initiated in the presence 2'-CDG. In another respect, however, 2'-CDG exhibited antiviral activity unlike that of ddC or PFA: a single 1-day treatment of hepatocytes with 2'-CDG blocked initiation of viral DNA synthesis for at least 8 days, irrespective of whether DHBV infection was carried out at the time of drug treatment or several days later. Furthermore, orally administered 2'-CDG was long-acting against DHBV in experimentally infected ducklings. Virus replication was delayed by up to 4 days in ducklings infected after administration of 2'-CDG. These observations of long-lasting efficacy in vitro and in vivo even after oral administration suggest that this inhibitor or a nucleoside with similar pharmacological properties may be ideal for reducing virus replication in patients with chronic HBV infection. Images PMID:8289335

  12. DNA Adducts of the Tobacco Carcinogens 2-Amino-9H-pyrido[2,3-b]indole and 4-Aminobiphenyl are Formed at Environmental Exposure levels and Persist in Human Hepatocytes

    PubMed Central

    Nauwelaërs, Gwendoline; Bellamri, Medjda; Fessard, Valérie; Turesky, Robert J.; Langouët, Sophie

    2013-01-01

    Aromatic amines and structurally related heterocyclic aromatic amines (HAAs) are produced during the combustion of tobacco or during the high-temperature cooking of meat. Exposure to some of these chemicals may contribute to the etiology of several common types of human cancers. 2-Amino-9H-pyrido[2,3-b]indole (AαC) is the most abundant HAA formed in mainstream tobacco smoke: it arises in amounts that are 25–100 times greater than the levels of the arylamine, 4-aminobiphenyl (4-ABP), a human carcinogen. 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) is a prevalent HAA formed in cooked meats. AαC and MeIQx are rodent carcinogens; however, their carcinogenic potency in humans is unknown. A preliminary assessment of the carcinogenic potential of these HAAs in humans was conducted by examining the capacity of primary human hepatocytes to form DNA adducts of AαC and MeIQx, in comparison to 4-ABP, followed by the kinetics of DNA adduct removal by cellular enzyme repair systems. The principal DNA adducts formed were N-(deoxyguanosin-8-yl) (dG-C8) adducts. Comparable levels of DNA adducts were formed with AαC and 4-ABP, whereas adduct formation was ~5-fold lower for MeIQx. dG-C8-AαC and dG-C8-4-ABP were formed at comparable levels in a concentration-dependent manner in human hepatocytes treated with procarcinogens over a ten thousand-fold concentration range (1 nM – 10 µM). Pretreatment of hepatocytes with furafylline, a selective inhibitor of cytochrome P450 1A2, resulted in a strong diminution of DNA adducts signifying that P450 1A2 is a major P450 isoform involved in bioactivation of these procarcinogens. The kinetics of adduct removal varied for each hepatocyte donor. Approximately half of the DNA adducts were removed within 24 h of treatment; however, the remaining lesions persisted over 5 days. The high levels of AαC present in tobacco smoke and its propensity to form persistent DNA adducts in human hepatocytes, suggests that AαC can contribute to

  13. Metabolite profiling of RCS-4, a novel synthetic cannabinoid designer drug, using human hepatocyte metabolism and TOF-MS

    PubMed Central

    Gandhi, Adarsh S; Zhu, Mingshe; Pang, Shaokun; Wohlfarth, Ariane; Scheidweiler, Karl B; Huestis, Marilyn A

    2014-01-01

    Background Since 2009, scheduling legislation of synthetic cannabinoids prompted new compound emergence to circumvent legal restrictions. 2-(4-methoxyphenyl)-1-(1-pentyl-indol-3-yl)methanone (RCS-4) is a potent cannabinoid receptor agonist sold in herbal smoking blends. Absence of parent synthetic cannabinoids in urine suggests the importance of metabolite identification for detecting RCS-4 consumption in clinical and forensic investigations. Materials & methods & Results With 1 h human hepatocyte incubation and TOF high-resolution MS, we identified 18 RCS-4 metabolites, many not yet reported. Most metabolites were hydroxylated with or without demethylation, carboxylation and dealkylation followed by glucuronidation. One additional sulfated metabolite was also observed. O-demethylation was the most common biotransformation and generated the major metabolite. Conclusion For the first time, we present a metabolic scheme of RCS-4 obtained from human hepatocytes, including Phase I and II metabolites. Metabolite structural information and associated high-resolution mass spectra can be employed for developing clinical and forensic laboratory RCS-4 urine screening methods. PMID:25046048

  14. Direct induction of hepatocyte-like cells from immortalized human bone marrow mesenchymal stem cells by overexpression of HNF4α.

    PubMed

    Hu, Xiaojun; Xie, Peiyi; Li, Weiqiang; Li, Zhengran; Shan, Hong

    2016-09-16

    Hepatocytes from human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are expected to be a useful source for cell transplantation. However, relatively low efficiency and repeatability of hepatic differentiation of human BM-MSCs remains an obstacle for clinical translation. Hepatocyte nuclear factor 4 alpha (HNF4α), a critical transcription factor, plays an essential role in the entire process of liver development. In this study, immortalized hBM-MSCs, UE7T-13 cells were transduced with a lentiviral vector containing HNF4α. The typical fibroblast-like morphology of the MSCs changed, and polygonal, epithelioid cells grew out after HNF4α transduction. In hepatocyte culture medium, HNF4α-transduced MSCs (E7-hHNF4α cells) strongly expressed the albumin (ALB), CYP2B6, alpha-1 antitrypsin (AAT), and FOXA2 mRNA and exhibited morphology markedly similar to that of mature hepatocytes. The E7-hHNF4α cells showed hepatic functions such as Indocyanine green (ICG) uptake and release, glycogen storage, urea production and ALB secretion. Approximately 28% of E7-hHNF4α cells expressed both ALB and AAT. Furthermore, these E7-hHNF4α cells via superior mesenteric vein (SMV) injection expressed human ALB in mouse chronic injured liver. In conclusion, this study represents a novel strategy by directly inducing hepatocyte-like cells from MSCs. PMID:27501760

  15. Comparative Cytotoxicity Study of Silver Nanoparticles (AgNPs) in a Variety of Rainbow Trout Cell Lines (RTL-W1, RTH-149, RTG-2) and Primary Hepatocytes

    PubMed Central

    Connolly, Mona; Fernandez-Cruz, Maria-Luisa; Quesada-Garcia, Alba; Alte, Luis; Segner, Helmut; Navas, Jose M.

    2015-01-01

    Among all classes of nanomaterials, silver nanoparticles (AgNPs) have potentially an important ecotoxicological impact, especially in freshwater environments. Fish are particularly susceptible to the toxic effects of silver ions and, with knowledge gaps regarding the contribution of dissolution and unique particle effects to AgNP toxicity, they represent a group of vulnerable organisms. Using cell lines (RTL-W1, RTH-149, RTG-2) and primary hepatocytes of rainbow trout (Oncorhynchus mykiss) as in vitro test systems, we assessed the cytotoxicity of the representative AgNP, NM-300K, and AgNO3 as an Ag+ ion source. Lack of AgNP interference with the cytotoxicity assays (AlamarBlue, CFDA-AM, NRU assay) and their simultaneous application point to the compatibility and usefulness of such a battery of assays. The RTH-149 and RTL-W1 liver cell lines exhibited similar sensitivity as primary hepatocytes towards AgNP toxicity. Leibovitz’s L-15 culture medium composition (high amino acid content) had an important influence on the behaviour and toxicity of AgNPs towards the RTL-W1 cell line. The obtained results demonstrate that, with careful consideration, such an in vitro approach can provide valuable toxicological data to be used in an integrated testing strategy for NM-300K risk assessment. PMID:26006119

  16. Effects of chloro-s-triazine herbicides and metabolites on aromatase activity in various human cell lines and on vitellogenin production in male carp hepatocytes.

    PubMed Central

    Sanderson, J T; Letcher, R J; Heneweer, M; Giesy, J P; van den Berg, M

    2001-01-01

    We investigated a potential mechanism for the estrogenic properties of three chloro-s-triazine herbicides and six metabolites in vitro in several cell systems. We determined effects on human aromatase (CYP19), the enzyme that converts androgens to estrogens, in H295R (adrenocortical carcinoma), JEG-3 (placental choriocarcinoma), and MCF-7 (breast cancer) cells; we determined effects on estrogen receptor-mediated induction of vitellogenin in primary hepatocyte cultures of adult male carp (Cyprinus carpio). In addition to atrazine, simazine, and propazine, two metabolites--atrazine-desethyl and atrazine-desisopropyl--induced aromatase activity in H295R cells concentration-dependently (0.3-30 microM) and with potencies similar to those of the parent triazines. After a 24-hr exposure to 30 microM of the triazines, an apparent maximum induction of about 2- to 2.5-fold was achieved. The induction responses were confirmed by similar increases in CYP19 mRNA levels, determined by reverse-transcriptase polymerase chain reaction. In JEG-3 cells, where basal aromatase expression is about 15-fold greater than in H295R cells, the induction responses were similar but less pronounced; aromatase expression in MCF-7 cells was neither detectable nor inducible under our culture conditions. The fully dealkylated metabolite atrazine-desethyl-desisopropyl and the three hydroxylated metabolites (2-OH-atrazine-desethyl, -desisopropyl, and -desethyl-desisopropyl) did not induce aromatase activity. None of the triazine herbicides nor their metabolites induced vitellogenin production in male carp hepatocytes; nor did they antagonize the induction of vitellogenin by 100 nM (EC(50) 17beta-estradiol. These findings together with other reports indicate that the estrogenic effects associated with the triazine herbicides in vivo are not estrogen receptor-mediated, but may be explained partly by their ability to induce aromatase in vitro. PMID:11675267

  17. Cryopreservation in situ of cell monolayers on collagen vitrigel membrane culture substrata: ready-to-use preparation of primary hepatocytes and ES cells.

    PubMed

    Miyamoto, Yoshitaka; Enosawa, Shin; Takeuchi, Tomoyo; Takezawa, Toshiaki

    2009-01-01

    Cryopreservation is generally performed on cells in suspension. In the case of adherent cells such as hepatocytes, a loss of their ability to attach is a more serious problem than a decreased viability after cryopreservation. We herein report a novel technology of direct in situ cryopreservation of cells cultured on collagen vitrigel membranes, which have excellent mechanical strength and can be easily handled by tweezers even when coated with cultured cells. Rat primary hepatocytes, mitomycin C-treated mouse fibroblasts (feeder cells for ES cells), and mouse ES cells on the feeder cells were cultured on collagen vitrigel membranes for 1 day. The membranes with cells attached were then plucked up from the dish, soaked in cryopreservation medium containing 10% dimethyl sulfoxide, frozen using a controlled-rate freezer, and transferred to liquid nitrogen. The cells cultured on plastic cell culture dishes were also frozen as controls. After storage in liquid nitrogen for periods from 1 week to 3 months, the cryopreserved membranes with the cells still attached were thawed by adding warmed culture medium. Cell viability estimated by morphology and functional staining with calcein showed significant improvement in comparison to cells cryopreserved without the collagen vitrigel membrane. The recoveries of living cells after cryopreservation were 26.7%, 76.2%, and 58.6% for rat hepatocytes, mitomycin C-treated mouse fibroblasts, and mouse ES cells on collagen vitrigel membranes, respectively. In contrast, essentially no cells at all remained on the plastic cell culture dishes after thawing. Because adherent cell storage under these conditions is very convenient, the use of this technique employing collagen vitrigel membranes should be generally applicable to the cryopreservation of adherent cells that are otherwise problematic to store as frozen stocks. PMID:19775524

  18. Activation of the Nrf2 Pathway by Inorganic Arsenic in Human Hepatocytes and the Role of Transcriptional Repressor Bach1

    PubMed Central

    Liu, Dan; Duan, Xiaoxu; Dong, Dandan; Bai, Caijun; Li, Xin; Sun, Guifan; Li, Bing

    2013-01-01

    Previous studies have proved that the environmental toxicant, inorganic arsenic, activates nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in many different cell types. This study tried to explore the hepatic Nrf2 pathway upon arsenic treatment comprehensively, since liver is one of the major target organs of arsenical toxicity. Our results showed that inorganic arsenic significantly induced Nrf2 protein and mRNA expression in Chang human hepatocytes. We also observed a dose-dependent increase of antioxidant response element- (ARE-) luciferase activity. Both the mRNA and protein levels of NAD(P)H:quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) were all upregulated dramatically. On the other hand, entry and accumulation of Nrf2 protein in the nucleus, while exportting the transcriptional repressor BTB and CNC homology 1 (Bach1) from nucleus to cytoplasm, were also confirmed by western blot and immunofluorescence assay. Our results therefore confirmed the arsenic-induced Nrf2 pathway activation in hepatocytes and also suggested that the translocation of Bach1 was associated with the regulation of Nrf2 pathway by arsenic. Hepatic Nrf2 pathway plays indispensable roles for cellular defenses against arsenic hepatotoxicity, and the interplay of Bach1 and Nrf2 may be helpful to understand the self-defensive responses and the diverse biological effects of arsenicals. PMID:23738048

  19. Hepatocyte Transplantation

    PubMed Central

    Mitry, Ragai R; Hughes, Robin D; Dhawan, Anil

    2011-01-01

    Hepatocyte transplantation (HTx) has been developed for use in liver-based metabolic disorders and in acute liver failure. Worldwide, there are around 80 patients that have been transplanted with hepatocytes. Almost all reported studies prove feasibility and safety of the procedure with short- to medium-term success. Availability of good quality hepatocytes (HCs) is the main limiting factor, and therefore alternative sources of cells such as stem cells are being investigated. Other limiting factors include cell engraftment, survival, and function of transplanted cells. It remains to be seen if progress in HTx research can overcome these hurdles leading to the wider use of the technique as an alternative to liver transplantation in the future. PMID:25755322

  20. Lipopolysaccharide Is Cleared from the Circulation by Hepatocytes via the Low Density Lipoprotein Receptor

    PubMed Central

    Topchiy, Elena; Cirstea, Mihai; Kong, HyeJin Julia; Boyd, John H.; Wang, Yingjin; Russell, James A.; Walley, Keith R.

    2016-01-01

    Sepsis is the leading cause of death in critically ill patients. While decreased Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) function improves clinical outcomes in murine and human sepsis, the mechanisms involved have not been fully elucidated. We tested the hypothesis that lipopolysaccharide (LPS), the major Gram-negative bacteria endotoxin, is cleared from the circulation by hepatocyte Low Density Lipoprotein Receptors (LDLR)—receptors downregulated by PCSK9. We directly visualized LPS uptake and found that LPS is rapidly taken up by hepatocytes into the cell periphery. Over the course of 4 hours LPS is transported towards the cell center. We next found that clearance of injected LPS from the blood was reduced substantially in Ldlr knockout (Ldlr-/-) mice compared to wild type controls and, simultaneously, hepatic uptake of LPS was also reduced in Ldlr-/- mice. Specifically examining the role of hepatocytes, we further found that primary hepatocytes isolated from Ldlr-/- mice had greatly decreased LPS uptake. In the HepG2 immortalized human hepatocyte cell line, LDLR silencing similarly resulted in decreased LPS uptake. PCSK9 treatment reduces LDLR density on hepatocytes and, therefore, was another independent strategy to test our hypothesis. Incubation with PCSK9 reduced LPS uptake by hepatocytes. Taken together, these findings demonstrate that hepatocytes clear LPS from the circulation via the LDLR and PCSK9 regulates LPS clearance from the circulation during sepsis by downregulation of hepatic LDLR. PMID:27171436

  1. Metabolic Consequences of TGFβ Stimulation in Cultured Primary Mouse Hepatocytes Screened from Transcript Data with ModeScore

    PubMed Central

    Hoppe, Andreas; Ilkavets, Iryna; Dooley, Steven; Holzhütter, Hermann-Georg

    2012-01-01

    TGFβ signaling plays a major role in the reorganization of liver tissue upon injury and is an important driver of chronic liver disease. This is achieved by a deep impact on a cohort of cellular functions. To comprehensively assess the full range of affected metabolic functions, transcript changes of cultured mouse hepatocytes were analyzed with a novel method (ModeScore), which predicts the activity of metabolic functions by scoring transcript expression changes with 987 reference flux distributions, which yielded the following hypotheses. TGFβ multiplies down-regulation of most metabolic functions occurring in culture stressed controls. This is especially pronounced for tyrosine degradation, urea synthesis, glucuronization capacity, and cholesterol synthesis. Ethanol degradation and creatine synthesis are down-regulated only in TGFβ treated hepatocytes, but not in the control. Among the few TGFβ dependently up-regulated functions, synthesis of various collagens is most pronounced. Further interesting findings include: down-regulation of glucose export is postponed by TGFβ, TGFβ up-regulates the synthesis capacity of ketone bodies only as an early response, TGFβ suppresses the strong up-regulation of Vanin, and TGFβ induces re-formation of ceramides and sphingomyelin. PMID:24957771

  2. A Hedgehog Survival Pathway in ‘Undead’ Lipotoxic Hepatocytes

    PubMed Central

    Kakisaka, Keisuke; Cazanave, Sophie C.; Werneburg, Nathan W.; Razumilava, Nataliya; Mertens, Joachim C.; Bronk, Steve F.; Gores, Gregory J.

    2012-01-01

    Background & Aims Ballooned hepatocytes in nonalcoholic steatohepatitis (NASH) generate sonic hedgehog (SHH). This observation is consistent with a cellular phenotype in which the cell death program has been initiated but cannot be executed. Our aim was to determine if ballooned hepatocytes have potentially disabled the cell death execution machinery, and if so, can their functional biology be modeled in vitro. Methods Immunohistochemistry was performed on human NASH specimens. In vitro studies were performed using Huh-7 cells with shRNA targeted knockdown of caspase 9 (shC9 cells) or primary hepatocytes from caspase 3−/− mice. Results Ballooned hepatocytes in NASH display diminished expression of the caspase 9. This phenotype was modeled using shC9 cells; these cells were resistant to lipoapoptosis by palmitate (PA) or lysophosphatidylcholine (LPC) despite lipid droplet formation. During lipid loading by either PA or LPC, shC9 cells activate JNK which via AP-1 induces SHH expression. An autocrine hedgehog survival signaling pathway was further delineated in both shC9 and caspase 3−/− cells during lipotoxic stress. Conclusion Ballooned hepatocytes in NASH downregulate caspase 9, a pivotal caspase executing the mitochondrial pathway of apoptosis. Hepatocytes engineered to reduce caspase 9 expression are resistant to lipoapoptosis, in part, due to a hedgehog autocrine survival signaling pathway. PMID:22641094

  3. Cellular and molecular analyses of hprt mutation in human hepatocyte L02 cells after exposure to carbon ions

    NASA Astrophysics Data System (ADS)

    Li, Qiang; He, Jing; Jin, Xiao-Dong; Gong, Li; Li, Sha

    Mutations play an important role in carcinogenesis. The quantitative evaluation of mutation induction by heavy charged particles helps us to delineate the risks of space radiation on astronauts, as well as the risks of heavy ions on patients during tumor therapy. Hprt mutation assay, which has been used as a biological dosimeter, is an ideal gene mutation test in mammalian cells in vitro. In order to provide basic data and evidence for the risk assessment of heavy ions, the relationships between hprt mutation induction and radiation dose in human hepatocyte L02 cells were investigated for highand low-LET carbon ions and X-rays. Moreover, the carbon ion induced hprt mutation spectrum was analyzed. In our study, human hepatocyte L02 cells were irradiated with carbon ions with LET of 30keV/µm and X-rays (0.2keV/µm), respectively. The survival fraction of L02 cells was measured by means of colony-forming assay. The mutation frequency was detected by measuring 6-thioguanine-resistant clones after 10 days of incubation at the presence of 15mg/L 6-TG. To obtain the mutation spectrum, 9 10 mutant cell clones at each dose were randomly selected from the 6-TG containing medium, and were further cultured and analyzed. The deletion patterns of the 9 exons of hprt gene were analyzed with multiplex polymerase chain reactions (multiplex PCR). Our results show that the number of mutants per 106 surviving cells increased with increasing the radiation dose for both the irradiations, and the mutation frequency increased up to 1Gy while reduced with increasing dose further. Partial deletion was the most dominant deletion pattern in the hprt mutant cells, and with the increase of dose, hprt genes tended to have more total deletions and less point deletions. It can be inferred that human hepatocyte L02 cells are more radiosensitive to high-LET carbon ions than to low-LET X-rays, and carbon ions are more effective in inducing hprt mutation in L02 cells. It has been also found that the

  4. Magentic Cell labeling of primary and stem cell-derived pig hepatocytes for MRI-based cell tracking of heptocytes transplantation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pig hepatocytes are an important investigational tool for optimizing hepatocyte transplantation schemes in both allogeneic and xenogeneic transplant scenarios. MRI can be used to serially monitor the transplanted cells, but only if the hepatocytes can be labeled with a magnetic particle. In this wo...

  5. Synergistic effects of tethered growth factors and adhesion ligands on DNA synthesis and function of primary hepatocytes cultured on soft synthetic hydrogels

    PubMed Central

    Mehta, Geeta; Williams, Courtney M.; Alvarez, Luis; Lesniewski, Martha; Kamm, Roger D.; Griffith, Linda G.

    2010-01-01

    The composition, presentation, and spatial orientation of extracellular matrix molecules and growth factors are key regulators of cell behavior. Here, we used self-assembling peptide nanofiber gels as a modular scaffold to investigate how fibronectin-derived adhesion ligands and different modes of epidermal growth factor (EGF) presentation synergistically regulate multiple facets of primary rat hepatocyte behavior in the context of a soft gel. In the presence of soluble EGF, inclusion of dimeric RGD and the heparin binding domain from fibronectin (HB) increased hepatocyte aggregation, spreading, and metabolic function compared to unmodified gels or gels modified with a single motif, but unlike rigid substrates, gels failed to induce DNA synthesis. Tethered EGF dramatically stimulated cell aggregation and spreading under all adhesive ligand conditions and also preserved metabolic function. Surprisingly, tethered EGF elicited DNA synthesis on gels with RGD and HB. Phenotypic differences between soluble and tethered EGF stimulation of cells on peptide gels are correlated with differences in expression and phosphorylation the EGF receptor and its heterodimerization partner ErbB2, and activation of the downstream signaling node ERK1/2. These modular matrices reveal new facets of hepatocellular biology in culture and may be more broadly useful in culture of other soft tissues. PMID:20304480

  6. Effects of clofibric acid alone and in combination with 17β-estradiol on mRNA abundance in primary hepatocytes isolated from rainbow trout.

    PubMed

    Sovadinová, I; Liedtke, A; Schirmer, K

    2014-09-01

    Clofibric acid (CA) is the active substance of lipid lowering drugs. It is resistant to degradation, polar in nature, and has been found ubiquitously in the aquatic environment. Though CA is classified as a peroxisomal proliferator in rodents and is considered as a potential endocrine disruptor, little information exists on the effects of CA in aquatic organisms, such as fish. In the present study, we examined the mRNA levels of peroxisome proliferator- and estrogen-sensitive genes on the exposure of primary rainbow trout (Oncorhynchus mykiss) hepatocytes to CA alone and in combination with the natural female sex hormone, 17β-estradiol (E2). Our results demonstrate that rainbow trout hepatocytes are relatively refractory to the effects of CA on the PPAR signaling pathway and lipid metabolism. Moreover, CA did not show recognizable estrogenic activity, but after the induction of vitellogenesis by E2, CA significantly reduced vitellogenin (VTG) mRNA abundance. Apparently, the indirect repression of VTG transcription, independent of estrogen receptors, occurred. The mechanism is not yet clearly understood but may involve disruption of the stabilization of VTG mRNA known to be induced by E2. PMID:24880017

  7. Controlled and reversible induction of differentiation and activation of adult human hepatocytes by a biphasic culture technique

    PubMed Central

    Auth, Marcus K.H.; Boost, Kim A.; Leckel, Kerstin; Beecken, Wolf-Dietrich; Engl, Tobias; Jonas, Dietger; Oppermann, Elsie; Hilgard, Philip; Markus, Bernd H.; Bechstein, Wolf-Otto; Blaheta, Roman A.

    2005-01-01

    AIM: Clinical application of human hepatocytes (HC) is hampered by the progressive loss of growth and differentiation in vitro. The object of the study was to evaluate the effect of a biphasic culture technique on expression and activation of growth factor receptors and differentiation of human adult HC. METHODS: Isolated HC were sequentially cultured in a hormone enriched differentiation medium (DM) containing nicotinamide, insulin, transferrin, selenium, and dexame-thasone or activation medium (AM) containing hepatocyte growth factor (HGF), epidermal growth factor (EGF), and granulocyte-macrophage colony-stimulating factor (GM-CSF). Expression, distribution and activation of the HC receptors (MET and EGFR) and the pattern of characteristic cytokeratin (CK) filaments were measured by fluorometry, confocal microscopy and Western blotting. RESULTS: In the biphasic culture system, HC underwent repeated cycles of activation (characterized by expression and activation of growth factor receptors) and re-differentiation (illustrated by distribution of typical filaments CK-18 but low or absent expression of CK-19). In AM increased expression of MET and EGFR was associated with receptor translocation into the cytoplasm and induction of atypical CK-19. In DM low expression of MET and EGFR was localized on the cell membrane and CK-19 was reduced. Receptor phosphorylation required embedding of HC in collagen type I gel. CONCLUSION: Control and reversible modulation of growth factor receptor activation of mature human HC can be accomplished in vitro, when defined signals from the extracellular matrix and sequential growth stimuli are provided. The biphasic technique helps overcome de-differentiation, which occurs during continuous stimulation by means of growth factors. PMID:15810072

  8. Metabolic Rate Constants for Hydroquinone in F344 Rat and Human Liver Isolated Hepatocytes: Application to a PBPK model.

    SciTech Connect

    Poet, Torka S.; Wu, Hong; English, J C.; Corley, Rick A.

    2004-11-15

    Hydroquinone (HQ) is an important industrial chemical that also occurs naturally in foods and in the leaves and bark of a number of plant species. Exposure of laboratory animals to HQ may result in a species-, sex-, and strain-specific nephrotoxicity. The sensitivity of male F344 vs. female F344 and Sprague-Dawley rats or B6C3F1 mice appears to be related to differences in the rates of formation and further metabolism of key nephrotoxic metabolites. Metabolic rate constants for the conversion of HQ through several metabolic steps to the mono-glutathione conjugate and subsequent detoxification via mercapturic acid were measured in suspension cultures of hepatocytes isolated from male F344 rats and humans. An in vitro mathematic kinetic model was used to analyze each metabolic step by simultaneously fitting the disappearance of each substrate and the appearance of subsequent metabolites. An iterative, nested approach was used whereby downstream metabolites were considered first and the model was constrained by the requirement that rate constants determined during analysis of individual metabolic steps must also satisfy the complete, integrated metabolism scheme, including competitive pathways. The results from this study indicated that the overall capacity for metabolism of HQ and its mono-glutathione conjugate is greater in hepatocytes from humans than those isolated from rats, suggesting a greater capacity for detoxification of the glutathione conjugates. Metabolic rate constants were applied to an existing physiologically based pharmacokinetic model and the model was used to predict total glutathione metabolites produced in the liver. The results showed that body burdens of these metabolites will be much higher in rats than humans.

  9. Improved Survival and Initiation of Differentiation of Human Induced Pluripotent Stem Cells to Hepatocyte-Like Cells upon Culture in William’s E Medium followed by Hepatocyte Differentiation Inducer Treatment

    PubMed Central

    Tomizawa, Minoru; Shinozaki, Fuminobu; Motoyoshi, Yasufumi; Sugiyama, Takao; Yamamoto, Shigenori; Ishige, Naoki

    2016-01-01

    Background Hepatocyte differentiation inducer (HDI) lacks both glucose and arginine, but is supplemented with galactose and ornithine, and is added together with other reagents such as apoptosis inhibitor and oncostatin M. Although human induced pluripotent stem (iPS) cells initiate hepatocyte differentiation, most die within 7 days. In this study, we investigated both HDI and conventional media for their potential to improve cell survival. Materials and Methods 201B7 iPS cells were cultured in conventional media. This consisted of three cycles of 5-day culture in William’s E (WE) medium, followed by a 2-day culture in HDI. Results Expression levels of α-feto protein (AFP) were higher in cells cultured in WE and in Dulbecco’s Modified Eagle’s Medium/Nutrient F-12 Ham (DF12). 201B7 cells expressed the highest AFP and albumin (ALB) when cultured in HDI for 2 days following 7-day culture in WE. After three cycles of 5-day culture in WE followed by 2 days in HDI, 201B7 cells expressed AFP and ALB 54 ± 2.3 (average ± standard deviation) and 73 ± 15.1 times higher, respectively, than those cultured in ReproFF (feeder-free condition). Conclusion 201B7 cells survived culture in WE for 7 days followed HDI for 2 days. After three cycles of culture under these conditions, hepatocyte differentiation was enhanced, as evidenced by increased AFP and ALB expression. PMID:27073925

  10. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes.

    PubMed

    Sanada, Takahiro; Tsukiyama-Kohara, Kyoko; Yamamoto, Naoki; Ezzikouri, Sayeh; Benjelloun, Soumaya; Murakami, Shuko; Tanaka, Yasuhito; Tateno, Chise; Kohara, Michinori

    2016-01-01

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3-6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10(5) copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10(4)-10(6) copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10(3) copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. PMID:26654952

  11. Mitochondrial Respiratory Defect Causes Dysfunctional Lactate Turnover via AMP-activated Protein Kinase Activation in Human-induced Pluripotent Stem Cell-derived Hepatocytes.

    PubMed

    Im, Ilkyun; Jang, Mi-Jin; Park, Seung Ju; Lee, Sang-Hee; Choi, Jin-Ho; Yoo, Han-Wook; Kim, Seyun; Han, Yong-Mahn

    2015-12-01

    A defective mitochondrial respiratory chain complex (DMRC) causes various metabolic disorders in humans. However, the pathophysiology of DMRC in the liver remains unclear. To understand DMRC pathophysiology in vitro, DMRC-induced pluripotent stem cells were generated from dermal fibroblasts of a DMRC patient who had a homoplasmic mutation (m.3398T→C) in the mitochondrion-encoded NADH dehydrogenase 1 (MTND1) gene and that differentiated into hepatocytes (DMRC hepatocytes) in vitro. DMRC hepatocytes showed abnormalities in mitochondrial characteristics, the NAD(+)/NADH ratio, the glycogen storage level, the lactate turnover rate, and AMPK activity. Intriguingly, low glycogen storage and transcription of lactate turnover-related genes in DMRC hepatocytes were recovered by inhibition of AMPK activity. Thus, AMPK activation led to metabolic changes in terms of glycogen storage and lactate turnover in DMRC hepatocytes. These data demonstrate for the first time that energy depletion may lead to lactic acidosis in the DMRC patient by reduction of lactate uptake via AMPK in liver. PMID:26491018

  12. In vitro glucuronidation of 2,2-bis(bromomethyl)-1,3-propanediol by microsomes and hepatocytes from rats and humans.

    PubMed

    Rad, Golriz; Hoehle, Simone I; Kuester, Robert K; Sipes, I Glenn

    2010-06-01

    2,2-Bis(bromomethyl)-1,3-propanediol (BMP) is a brominated flame retardant used in unsaturated polyester resins. In a 2-year bioassay BMP was shown to be a multisite carcinogen in rats and mice. Because glucuronidation is the key metabolic transformation of BMP by rats, in this study the in vitro hepatic glucuronidation of BMP was compared across several species. In addition, the glucuronidation activities of human intestinal microsomes and specific human hepatic UDP-glucuronosyltransferase (UGT) enzymes for BMP were determined. To explore other possible routes of metabolism for BMP, studies were conducted with rat and human hepatocytes. Incubation of hepatic microsomes with BMP in the presence of UDP-glucuronic acid resulted in the formation of a BMP monoglucuronide. The order of hepatic microsomal glucuronidation activity of BMP was rats, mice > hamsters > monkeys > humans. The rate of glucuronidation by rat hepatic microsomes was 90-fold greater than that of human hepatic microsomes. Human intestinal microsomes converted BMP to BMP glucuronide at a rate even lower than that of human hepatic microsomes. Among the human UGT enzymes tested, only UGT2B7 had detectable glucuronidation activity for BMP. BMP monoglucuronide was the only metabolite formed when BMP was incubated with suspensions of freshly isolated hepatocytes from male F-344 rats or with cryopreserved human hepatocytes. Glucuronidation of BMP in human hepatocytes was extremely low. Overall, the results support in vivo studies in rats in which BMP glucuronide was the only metabolite found. The poor glucuronidation capacity of humans for BMP suggests that the pharmacokinetic profile of BMP in humans will be dramatically different from that of rodents. PMID:20200232

  13. In Vitro Glucuronidation of 2,2-Bis(bromomethyl)-1,3-propanediol by Microsomes and Hepatocytes from Rats and Humans

    PubMed Central

    Rad, Golriz; Hoehle, Simone I.; Kuester, Robert K.

    2010-01-01

    2,2-Bis(bromomethyl)-1,3-propanediol (BMP) is a brominated flame retardant used in unsaturated polyester resins. In a 2-year bioassay BMP was shown to be a multisite carcinogen in rats and mice. Because glucuronidation is the key metabolic transformation of BMP by rats, in this study the in vitro hepatic glucuronidation of BMP was compared across several species. In addition, the glucuronidation activities of human intestinal microsomes and specific human hepatic UDP-glucuronosyltransferase (UGT) enzymes for BMP were determined. To explore other possible routes of metabolism for BMP, studies were conducted with rat and human hepatocytes. Incubation of hepatic microsomes with BMP in the presence of UDP-glucuronic acid resulted in the formation of a BMP monoglucuronide. The order of hepatic microsomal glucuronidation activity of BMP was rats, mice ≫ hamsters > monkeys ⋙ humans. The rate of glucuronidation by rat hepatic microsomes was 90-fold greater than that of human hepatic microsomes. Human intestinal microsomes converted BMP to BMP glucuronide at a rate even lower than that of human hepatic microsomes. Among the human UGT enzymes tested, only UGT2B7 had detectable glucuronidation activity for BMP. BMP monoglucuronide was the only metabolite formed when BMP was incubated with suspensions of freshly isolated hepatocytes from male F-344 rats or with cryopreserved human hepatocytes. Glucuronidation of BMP in human hepatocytes was extremely low. Overall, the results support in vivo studies in rats in which BMP glucuronide was the only metabolite found. The poor glucuronidation capacity of humans for BMP suggests that the pharmacokinetic profile of BMP in humans will be dramatically different from that of rodents. PMID:20200232

  14. HepatoNet1: a comprehensive metabolic reconstruction of the human hepatocyte for the analysis of liver physiology

    PubMed Central

    Gille, Christoph; Bölling, Christian; Hoppe, Andreas; Bulik, Sascha; Hoffmann, Sabrina; Hübner, Katrin; Karlstädt, Anja; Ganeshan, Ramanan; König, Matthias; Rother, Kristian; Weidlich, Michael; Behre, Jörn; Holzhütter, Herrmann-Georg

    2010-01-01

    We present HepatoNet1, the first reconstruction of a comprehensive metabolic network of the human hepatocyte that is shown to accomplish a large canon of known metabolic liver functions. The network comprises 777 metabolites in six intracellular and two extracellular compartments and 2539 reactions, including 1466 transport reactions. It is based on the manual evaluation of >1500 original scientific research publications to warrant a high-quality evidence-based model. The final network is the result of an iterative process of data compilation and rigorous computational testing of network functionality by means of constraint-based modeling techniques. Taking the hepatic detoxification of ammonia as an example, we show how the availability of nutrients and oxygen may modulate the interplay of various metabolic pathways to allow an efficient response of the liver to perturbations of the homeostasis of blood compounds. PMID:20823849

  15. Differential Response of Human Hepatocyte Chromatin to HDAC Inhibitors as a Function of Microenvironmental Glucose Level.

    PubMed

    Felisbino, Marina Barreto; Alves da Costa, Thiago; Gatti, Maria Silvia Viccari; Mello, Maria Luiza Silveira

    2016-10-01

    Diabetes is a complex multifactorial disorder characterized by chronic hyperglycemia due to impaired insulin secretion. Recent observations suggest that the complexity of the disease cannot be entirely accounted for genetic predisposition and a compelling argument for an epigenetic component is rapidly emerging. The use of histone deacetylase inhibitor (HDACi) in clinical setting is an emerging area of investigation. In this study, we have aimed to understand and compare the response of hepatocyte chromatin to valproic acid (VPA) and trichostatin A (TSA) treatments under normoglycemic or hyperglycemic conditions to expand our knowledge about the consequences of HDACi treatment in a diabetes cell model. Under normoglycemic conditions, these treatments promoted chromatin remodeling, as assessed by image analysis and H3K9ac and H3K9me2 abundance. Simultaneously, H3K9ac marks shifted to the nuclear periphery accompanied by HP1 dissociation from the heterochromatin and a G1 cell cycle arrest. More striking changes in the cell cycle progression and mitotic ratios required drastic treatment. Under hyperglycemic conditions, high glucose per se promoted chromatin changes similar to those promoted by VPA and TSA. Nonetheless, these results were not intensified in cells treated with HDACis under hyperglycemic conditions. Despite the absence of morphological changes being promoted, HDACi treatment seems to confer a physiological meaning, ameliorating the cellular hyperglycemic state through reduction of glucose production. These observations allow us to conclude that the glucose level to which the hepatocytes are subjected affects how chromatin responds to HDACi and their action under high-glucose environment might not reflect on chromatin remodeling. J. Cell. Physiol. 231: 2257-2265, 2016. © 2016 Wiley Periodicals, Inc. PMID:26888775

  16. Regulation of cytochrome P450 mRNA expression in primary porcine hepatocytes by selected secondary plant metabolites from chicory (Cichorium intybus L.).

    PubMed

    Rasmussen, Martin Krøyer; Klausen, Christina Lindgaard; Ekstrand, Bo

    2014-03-01

    Chicory (Cichorium intybus) has been shown to induce enzymes of pharmacokinetic relevance (cytochrome P450; CYP). The aim of this study was to investigate the effects of selected secondary plant metabolites with a global extract of chicory root, on the expression of hepatic CYP mRNA (1A2, 2A19, 2C33, 2D25, 2E1 and 3A29), using primary porcine hepatocytes. Of the tested secondary plant metabolites, artemisinin, scoparone, lactucin and esculetin all induced increased expression of specific CYPs, while esculin showed no effect. In contrast, a global extract of chicory root decreased the expression of CYP1A2, 2C33, 2D25 and 3A29 at high concentrations. The results suggest that purified secondary metabolites from chicory affect CYP expression and thereby might affect detoxification in general, and that global extracts of plants can have effects different from individual components. PMID:24176340

  17. [Primary human demodicosis. A disease sui generis].

    PubMed

    Hsu, C-K; Zink, A; Wei, K-J; Dzika, E; Plewig, G; Chen, W

    2015-03-01

    Human Demodex mites (Demodex folliculorum and Demodex brevis) are unique in that they are an obligate human ectoparasite that can inhabit the pilosebaceous unit lifelong without causing obvious host immune response in most cases. The mode of symbiosis between humans and human Demodex mites is unclear, while the pathogenicity of human Demodex mites in many inflammatory skin diseases is now better understood. Primary human demodicosis is a skin disease sui generis not associated with local or systemic immunosuppression. Diagnosis is often underestimated and differentiation from folliculitis, papulopustular rosacea and perioral dermatitis is not always straightforward. Dependent on the morphology and degree of inflammation, the clinical manifestations can be classified into spinulate, papulopustular, nodulocystic, crustic and fulminant demodicosis. Therapy success can be achieved only with acaricides/arachidicides. The effective doses, optimal regimen and antimicrobial resistance remain to be determined. PMID:25744530

  18. An improvement in the attaching capability of cryopreserved human hepatocytes by a proteinaceous high molecule, sericin, in the serum-free solution.

    PubMed

    Miyamoto, Yoshitaka; Teramoto, Naozumi; Hayashi, Shuji; Enosawa, Shin

    2010-01-01

    The methodology of cryopreservation of human hepatocytes remains unsatisfactory. Even when the viability of thawed cells is tolerable, the cells often lose the attaching capability to a culture dish, resulting in the cells' inability to survive. Previously, we described the effectiveness of maltose on the attachment of hepatocytes. This article demonstrates that a silk-derived high molecular protein, sericin, improves the cell-attaching capability in the serum-free freezing medium. When human hepatocytes [initial viability: 60.9 ± 3.1% (mean ± SD, n = 3)] were frozen with serum-free Dulbecco's modified Eagle medium (DMEM) containing 10% dimethyl sulfoxide (DMSO), the viability was 29.4 ± 3.2% and the cell-attaching capability 20.4 ± 4.1%. On the other hand, DMEM containing 10% DMSO and 1% sericin increased the values to 45.0 ± 0.8% and 26.2 ± 3.2%. Moreover, the addition of 0.1 mol/L maltose to the sericin-containing medium improved to 42.2 ± 3.2% and 51.1 ± 1.0%, as we demonstrated in a previous report. The present results indicated that sericin combined with maltose is a novel additive in the serum-free freezing medium for human hepatocytes. PMID:20525438

  19. Pleiotropic effects of gold(I) mixed-ligand complexes of 9-deazahypoxanthine on transcriptional activity of receptors for steroid hormones, nuclear receptors and xenoreceptors in human hepatocytes and cell lines.

    PubMed

    Kubešová, Kateřina; Trávníček, Zdeněk; Dvořák, Zdeněk

    2016-10-01

    Development of metal-based compounds is an important research avenue in anti-cancer and anti-inflammatory drug discovery. Here we examined the effects of three gold (I) mixed-ligand complexes with the general formula [Au(Ln)(PPh3)] (1, 2, 3) involving triphenylphosphine (PPh3) and a deprotonated form of O-substituted derivatives of 9-deazahypoxanthine (Ln) on the transcriptional activity of aryl hydrocarbon receptor (AhR), androgen receptor (AR), glucocorticoid receptor (GR), thyroid receptor (TR), pregnane X receptor (PXR) and vitamin D receptor (VDR), employing gene reporter assays. In addition, we measured mRNA (RT-PCR) and protein (western blot) expression of target genes for those receptors, including drug-metabolizing P450s, in primary human hepatocytes and cancer cell lines LS180 and HepG2. The tested compounds displayed anti-glucocorticoid effects, as revealed by inhibition of dexamethasone-inducible transcriptional activity of GR and down-regulation of tyrosine aminotransferase. All the compounds slightly and dose-dependently activated PXR and AhR, and moderately induced CYP3A4 and CYP1A1/2 genes in human hepatocytes and LS180 cells. The complexes antagonized basal and ligand-activated AR and VDR, indicating inverse agonist behaviour. Both basal and thyroid hormone-inducible transcriptional activity of TR was dose-dependently increased by all tested compounds. In contrast, the expression of SPOT14 mRNA was decreased by tested compounds in human hepatocytes and HepG2 cells. In conclusion, if intended for human pharmacotherapy, the potential of the complexes 1-3 to influence studied receptors should be taken in account. PMID:27318977

  20. Metabolic pathways of 4-bromo-2,5-dimethoxyphenethylamine (2C-B): analysis of phase I metabolism with hepatocytes of six species including human.

    PubMed

    Carmo, Helena; Hengstler, Jan G; de Boer, Douwe; Ringel, Michael; Remião, Fernando; Carvalho, Félix; Fernandes, Eduarda; dos Reys, Lesseps A; Oesch, Franz; de Lourdes Bastos, Maria

    2005-01-01

    4-Bromo-2,5-dimethoxyphenethylamine (2C-B) is a psychoactive designer drug of abuse that is sold under the street names "Venus", "Bromo", "Erox", "XTC" or "Nexus". Concern has been raised because only little is known about its toxicity and metabolism in humans. In the present study we incubated 2C-B with human, monkey, dog, rabbit, rat and mouse hepatocytes to identify the metabolites formed and to determine possible toxic effects as evidenced by an ATP assay. Our data allow construction of the main metabolic pathways of 2C-B. Oxidative deamination results in the 2-(4-bromo-2,5-dimethoxyphenyl)-ethanol (BDMPE) and 4-bromo-2,5-dimethoxyphenylacetic acid (BDMPAA) metabolites. Additionally, 4-bromo-2,5-dimethoxybenzoic acid (BDMBA) can be produced also by oxidative deamination. Further metabolism of BDMPE and BDMPAA may occur by demethylation. Alternatively, the later metabolites can be generated by demethylation of 2C-B followed by oxidative deamination. Two remarkable interspecies differences in metabolism of 2C-B were observed (i) a hitherto unknown metabolite, 4-bromo-2,5-dimethoxy-phenol (BDMP), was identified after incubation only with mouse hepatocytes; (ii) 2-(4-bromo-2-hydroxy-5-methoxyphenyl)-ethanol (B-2-HMPE) was produced by hepatocytes from human, monkey and rabbit but not by dog, rat and mouse. Comparing the toxic effects of 2C-B between hepatocytes of the six examined species we observed only minor interspecies differences. However, large inter-individual differences in susceptibility of hepatocytes from three human donors were observed. PMID:15590110

  1. Effects of Adenovirus-Mediated Delivery of the Human Hepatocyte Growth Factor Gene in Experimental Radiation-Induced Heart Disease

    SciTech Connect

    Hu Shunying; Chen Yundai; Li Libing; Chen Jinlong; Wu Bin; Zhou, Xiao; Zhi Guang; Li Qingfang; Wang Rongliang; Duan Haifeng; Guo Zikuan; Yang Yuefeng; Xiao Fengjun; Wang Hua; Wang Lisheng

    2009-12-01

    Purpose: Irradiation to the heart may lead to late cardiovascular complications. The purpose of this study was to investigate whether adenovirus-mediated delivery of the human hepatocyte growth factor gene could reduce post-irradiation damage of the rat heart and improve heart function. Methods and Materials: Twenty rats received single-dose irradiation of 20 Gy gamma ray locally to the heart and were randomized into two groups. Two weeks after irradiation, these two groups of rats received Ad-HGF or mock adenovirus vector intramyocardial injection, respectively. Another 10 rats served as sham-irradiated controls. At post-irradiation Day 120, myocardial perfusion was tested by myocardial contrast echocardiography with contrast agent injected intravenously. At post-irradiation Day 180, cardiac function was assessed using the Langendorff technique with an isolated working heart model, after which heart samples were collected for histological evaluation. Results: Myocardial blood flow was significantly improved in HGF-treated animals as measured by myocardial contrast echocardiography at post-irradiation Day 120 . At post-irradiation Day 180, cardiac function was significantly improved in the HGF group compared with mock vector group, as measured by left ventricular peak systolic pressure (58.80 +- 9.01 vs. 41.94 +- 6.65 mm Hg, p < 0.05), the maximum dP/dt (5634 +- 1303 vs. 1667 +- 304 mm Hg/s, p < 0.01), and the minimum dP/dt (3477 +- 1084 vs. 1566 +- 499 mm Hg/s, p < 0.05). Picrosirius red staining analysis also revealed a significant reduction of fibrosis in the HGF group. Conclusion: Based on the study findings, hepatocyte growth factor gene transfer can attenuate radiation-induced cardiac injury and can preserve cardiac function.

  2. Analysis of intracellular reducing levels in human hepatocytes on three-dimensional focusing microchip.

    PubMed

    Xu, Chunxiu; Cai, Longfei

    2014-02-01

    A novel three-dimensional hydrodynamic focusing microfluidic device integrated with high-throughput cell sampling and detection of intracellular contents is presented. It has a pivotal role in maintaining the reducing environment in cells. Intracellular reducing species such as vitamin C and glutathione in normal and tumor cells were labeled by a newly synthesized 2,2,6,6-tetramethyl-piperidine-1-oxyl-based fluorescent probe. Hepatocytes are adherent cells, which are prone to attaching to the channel surface. To avoid the attachment of cells on the channel surface, a single channel microchip with three sheath-flow channels located on both sides of and below the sampling channel was developed. Hydrostatic pressure generated by emptying the sample waste reservoir was used as driving force of fluid on the microchip. Owing to the difference between the liquid levels of the reservoirs, the labeled cells were three-dimensional hydrodynamically focused and transported from the sample reservoir to the sample waste reservoir. Hydrostatic pressure takes advantage of its ease of generation on a microfluidic chip without any external pressure pump, which drives three sheath-flow streams to constrain a sample flow stream into a narrow stream to avoid blockage of the sampling channel by adhered cells. The intracellular reducing levels of HepG2 cells and L02 cells were detected by home-built laser-induced fluorescence detector. The analysis throughput achieved in this microfluidic system was about 59-68 cells/min. PMID:23297173

  3. Initial response and cellular protection through the Keap1/Nrf2 system during the exposure of primary mouse hepatocytes to 1,2-naphthoquinone.

    PubMed

    Miura, Takashi; Shinkai, Yasuhiro; Jiang, Hai-Yan; Iwamoto, Noriko; Sumi, Daigo; Taguchi, Keiko; Yamamoto, Masayuki; Jinno, Hideto; Tanaka-Kagawa, Toshiko; Cho, Arthur K; Kumagai, Yoshito

    2011-04-18

    Quinones are reactive chemical species that cause cellular damage by modifying protein thiols and/or catalyzing the reduction of oxygen to reactive oxygen species, thereby promoting oxidative stress. Transcription factor Nrf2 plays a crucial role in cellular defense against electrophilic modification and oxidative stress. In studies using 1,2-naphthoquinone (1,2-NQ) as a model quinone, we found that Keap1, the negative regulator of Nrf2, was readily arylated at its reactive thiols by 1,2-NQ. Exposure of primary mouse hepatocytes to 1,2-NQ resulted in the activation of Nrf2 and the upregulation of some of Nrf2's downstream genes. This interaction was further investigated in hepatocytes from Nrf2 knockout mice in which the proteins responsible for the metabolism and excretion of 1,2-NQ are minimally expressed. The chemical modification of cellular proteins by 1,2-NQ was enhanced by Nrf2 deletion, resulting in increased toxicity. However, deletion of the negative regulatory protein, Keap1, drastically reduced the covalent binding by 1,2-NQ and its cellular toxicity. Experiments with chemicals that inhibit the biotransformation and extracellular excretion of 1,2-NQ suggest that 1,2-NQ undergoes detoxification and excretion into the extracellular space predominantly by two-electron reduction and subsequent glucuronidation by NAD(P)H:quinone oxidoreductase 1 and uridine 5'-diphosphate-glucuronosyltransferases, followed by multidrug resistance-associated protein-dependent excretion. These findings suggest that the Keap1/Nrf2 system is essential for the prevention of cell damage resulting from exposure to 1,2-NQ. PMID:21384861

  4. Differential Regulation of Gene Expression by Cholesterol Biosynthesis Inhibitors That Reduce (Pravastatin) or Enhance (Squalestatin 1) Nonsterol Isoprenoid Levels in Primary Cultured Mouse and Rat Hepatocytes.

    PubMed

    Rondini, Elizabeth A; Duniec-Dmuchowski, Zofia; Cukovic, Daniela; Dombkowski, Alan A; Kocarek, Thomas A

    2016-08-01

    Squalene synthase inhibitors (SSIs), such as squalestatin 1 (SQ1), reduce cholesterol biosynthesis but cause the accumulation of isoprenoids derived from farnesyl pyrophosphate (FPP), which can modulate the activity of nuclear receptors, including the constitutive androstane receptor (CAR), farnesoid X receptor, and peroxisome proliferator-activated receptors (PPARs). In comparison, 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (e.g., pravastatin) inhibit production of both cholesterol and nonsterol isoprenoids. To characterize the effects of isoprenoids on hepatocellular physiology, microarrays were used to compare orthologous gene expression from primary cultured mouse and rat hepatocytes that were treated with either SQ1 or pravastatin. Compared with controls, 47 orthologs were affected by both inhibitors, 90 were affected only by SQ1, and 51 were unique to pravastatin treatment (P < 0.05, ≥1.5-fold change). When the effects of SQ1 and pravastatin were compared directly, 162 orthologs were found to be differentially coregulated between the two treatments. Genes involved in cholesterol and unsaturated fatty acid biosynthesis were up-regulated by both inhibitors, consistent with cholesterol depletion; however, the extent of induction was greater in rat than in mouse hepatocytes. SQ1 induced several orthologs associated with microsomal, peroxisomal, and mitochondrial fatty acid oxidation and repressed orthologs involved in cell cycle regulation. By comparison, pravastatin repressed the expression of orthologs involved in retinol and xenobiotic metabolism. Several of the metabolic genes altered by isoprenoids were inducible by a PPARα agonist, whereas cytochrome P450 isoform 2B was inducible by activators of CAR. Our findings indicate that SSIs uniquely influence cellular lipid metabolism and cell cycle regulation, probably due to FPP catabolism through the farnesol pathway. PMID:27225895

  5. Detection of primary cilia in human glioblastoma

    PubMed Central

    Sarkisian, Matthew R.; Siebzehnrubl, Dorit; Hoang-Minh, Lan; Deleyrolle, Loic; Silver, Daniel J.; Siebzehnrubl, Florian A.; Guadiana, Sarah M.; Srivinasan, Gayathri; Semple-Rowland, Susan; Harrison, Jeffrey K.; Steindler, Dennis A.; Reynolds, Brent A.

    2015-01-01

    Glioblastoma (GBM) is the most common malignant adult brain tumor and carries a poor prognosis due to primary and acquired resistance. While many cellular features of GBM have been documented, it is unclear if cells within these tumors extend a primary cilium, an organelle whose associated signaling pathways may regulate proliferation, migration, and survival of neural precursor and tumor cells. Using immunohistochemical and electron microscopy (EM) techniques, we screened human GBM tumor biopsies and primary cell lines for cilia. Immunocytochemical staining of five primary GBM cell lines revealed that between 8 and 25 % of the cells in each line possessed gamma tubulin-positive basal bodies from which extended acetylated, alpha-tubulin-positive axonemes. EM analyses confirmed the presence of cilia at the cell surface and revealed that their axonemes contained organized networks of microtubules, a structural feature consistent with our detection of IFT88 and Arl13b, two trafficked cilia proteins, along the lengths of the axonemes. Notably, cilia were detected in each of 23 tumor biopsies (22 primary and 1 recurrent) examined. These cilia were distributed across the tumor landscape including regions proximal to the vasculature and within necrotic areas. Moreover, ciliated cells within these tumors co-stained with Ki67, a marker for actively dividing cells, and ZEB1, a transcription factor that is upregulated in GBM and linked to tumor initiation, invasion, and chemoresistance. Collectively, our data show that subpopulations of cells within human GBM tumors are ciliated. In view of mounting evidence supporting roles of primary cilia in tumor initiation and propagation, it is likely that further study of the effects of cilia on GBM tumor cell function will improve our understanding of GBM pathogenesis and may provide new directions for GBM treatment strategies. PMID:24510433

  6. Involvement of hepatocyte growth factor-induced epithelial-mesenchymal transition in human adenomyosis.

    PubMed

    Khan, Khaleque Newaz; Kitajima, Michio; Hiraki, Koichi; Fujishita, Akira; Nakashima, Masahiro; Masuzaki, Hideaki

    2015-02-01

    Adenomyosis is commonly believed to arise from the basalis endometrium. As an estromedin growth factor, hepatocyte growth factor (HGF) exhibits multiple functions in endometriosis, a disease commonly believed to arise from the functionalis endometrium. Here, we investigated the role of HGF in the occurrence of epithelial-mesenchymal transition (EMT) in adenomyosis. Full-thickness-biopsy specimens from endometrium to myometrium were collected after hysterectomy from women with and without adenomyosis. The relationship between HGF and E-cadherin (epithelial cell marker) and N-cadherin (mesenchymal cell markers) was examined at the gene and protein levels using endometrial epithelial cells (EECs) in culture and tissues by quantitative RT-PCR and immunohistochemistry. The gene and protein expressions of two transcriptional repressors of E-cadherin, SLUG and SNAIL, were examined using Ishikawa cells and in response to HGF and estrogen (E2). HGF down-regulated E-cadherin and up-regulated N-cadherin mRNA expression in EECs, and an inverse relationship in protein expression between HGF and E-cadherin was observed in basalis endometria derived from women with diffuse and focal adenomyosis. HGF induced morphological changes of EECs from a cobblestone-like appearance to spindle-shaped cells and promoted migration of EECs. Ishikawa cells exhibited up-regulation of SLUG/SNAIL gene expression in response to both HGF and E2 with an additive effect between them. HGF- and E2-promoted SLUG/SNAIL gene expression was significantly abrogated after pretreatment of cells with anti-HGF antibody or ICI 182720, an estrogen receptor antagonist. HGF may be involved in gland invagination deep into the myometrium by inducing EMT at the endo-myometrial junction in women with adenomyosis. PMID:25505196

  7. Insulin inhibits delta-aminolevulinate synthase gene expression in rat hepatocytes and human hepatoma cells.

    PubMed

    Scassa, M E; Varone, C L; Montero, L; Cánepa, E T

    1998-11-01

    Insulin has been known to regulate intracellular metabolism by modifying the activity or location of many enzymes but it is only in the past few years that the regulation of gene expression is recognized to be a major action of this hormone. The present work provides evidences that insulin inhibits delta-aminolevulinate synthase (ALA-S) gene expression, the enzyme which governs the rate-limiting step in heme biosynthesis. The addition of 5 nM insulin to hepatocytes culture led to a significant decrease of both basal and phenobarbital-induced ALA-S mRNA in a dose-dependent manner, as measured by Northern and slot-blot analysis. Several clues as to how insulin regulates ALA-S transcription were determined. The inhibitory effect is achieved at physiological concentrations but much higher proinsulin doses are needed. Insulin's effect is rapid, quite specific, and protein synthesis is not required. Moreover, ALA-S mRNA half-life is not modified by the presence of the peptidic hormone. Our results demonstrate that the insulin effect is dominant; it overrides 8-CPT-cAMP plus phenobarbital-mediated induction. Also, insulin requires the activation of protein kinase C to exert its full effect. On the other hand, a 870-bp fragment of the ALA-S promoter region is able to sustain the inhibition of CAT expression in plasmid-transfected HepG2 cells. Thus, these results indicate that insulin plays an important role in regulating ALA-S expression by inhibiting its transcription. PMID:9806796

  8. Gene targeting in primary human trophoblasts

    PubMed Central

    Rosario, Fredrick J; Sadovsky, Yoel; Jansson, Thomas

    2012-01-01

    Studies in primary human trophoblasts provide critical insights into placental function in normal and complicated pregnancies. Mechanistic studies in these cells require experimental tools to modulate gene expression. Lipid-based methods to transfect primary trophoblasts are fairly simple to use and allow for the efficient delivery of nucleic acids, but potential toxic effects limit these methods. Viral vectors are versatile transfection tools of native trophoblastic or foreign cDNAs, providing high transfection efficiency, low toxicity and stable DNA integration into the trophoblast genome. RNA interference (RNAi), using small interfering RNA (siRNA) or microRNA, constitutes a powerful approach to silence trophoblast genes. However, off-target effects, such as regulation of unintended complementary transcripts, inflammatory responses and saturation of the endogenous RNAi machinery, are significant concerns. Strategies to minimize off-target effects include using multiple individual siRNAs, elimination of pro-inflammatory sequences in the siRNA construct and chemical modification of a nucleotide in the guide strand or of the ribose moiety. Tools for efficient gene targeting in primary human trophoblasts are currently available, albeit not yet extensively validated. These methods are critical for exploring the function of human trophoblast genes and may provide a foundation for the future application of gene therapy that targets placental trophoblasts. PMID:22831880

  9. Platelet-activating factor stimulates metabolism of phosphoinositides via phospholipase A2 in primary cultured rat hepatocytes

    SciTech Connect

    Okayasu, T.; Hasegawa, K.; Ishibashi, T.

    1987-07-01

    Addition of platelet-activating factor (PAF) to cells doubly labeled with (/sup 14/C)glycerol plus (/sup 3/H)arachidonic acid resulted in a transient decrease of (/sup 14/C)glycerol-labeled phosphatidylinositol (PI) and a transient increase of (/sup 14/C)glycerol-labeled lysophosphatidylinositol (LPI). (/sup 3/H)Arachidonate-labeled PI, on the other hand, decreased in a time-dependent manner. The radioactivity in phosphatidylethanolamine, phosphatidylcholine, sphingomyelin, and phosphatidylserine did not change significantly. The /sup 3/H//sup 14/C ratio decreased in PI in a time-dependent manner, suggesting the involvement of a phospholipase A2 activity. Although PAF also induced a gradual increase of diacylglycerol (DG), the increase of (/sup 14/C)glycerol-labeled DG paralleled the loss of triacyl (/sup 14/C)glycerol and the /sup 3/H//sup 14/C ratio of DG was 16 times smaller than that of PI. Thus, DG seemed not to be derived from PI. In myo- (/sup 3/H)inositol-prelabeled cells, PAF induced a transient decrease of (/sup 3/H)phosphatidylinositol-4,5-bis-phosphate (TPI) and (/sup 3/H)phosphatidylinositol-4-phosphate (DPI) at 1 min. PAF stimulation of cultured hepatocytes prelabeled with /sup 32/Pi induced a transient decrease of (/sup 32/P)polyphosphoinositides at 20 sec to 1 min. (/sup 32/P)LPI appeared within 10 sec after stimulation and paralleled the loss of (/sup 32/P)PI. (/sup 3/H)Inositol triphosphate, (/sup 3/H)inositol diphosphate, and (/sup 3/H)inositol phosphate, which increased in a time-dependent manner upon stimulation with adrenaline, did not accumulate with the stimulation due to PAF. These observations indicate that PAF causes degradation of inositol phospholipids via phospholipase A2 and induces a subsequent resynthesis of these phospholipids.

  10. Garlic organosulfur compounds upregulate the expression of the pi class of glutathione S-transferase in rat primary hepatocytes.

    PubMed

    Tsai, Chia-Wen; Yang, Jaw-Ji; Chen, Haw-Wen; Sheen, Lee-Yan; Lii, Chong-Kuei

    2005-11-01

    The chemopreventive property of garlic is related in part to its induction of phase II detoxification enzymes. In the present study, we investigated the modulatory effect of 3 garlic organosulfur compounds, i.e., diallyl sulfide (DAS), diallyl disulfide (DADS), and diallyl trisulfide (DATS), which differ in their number of sulfur atoms, on the gene expression of the pi class of glutathione S-transferase (GSTP). Hepatocytes isolated from male Sprague-Dawley rats were cultured with 50-200 micromol/L of DAS, DADS, or DATS for 24 h. DADS and DATS increased GST activity toward ethacrynic acid by 40 and 66%, respectively (P < 0.05). Moreover, both garlic allyl sulfides dose dependently induced GSTP mRNA and protein expression. DATS increased the protein level more than DADS (P < 0.05). In contrast, DAS did not affect the activity or the protein or mRNA levels of this phase II drug-metabolizing enzyme. In Clone 9 liver cells, the pTA-luciferase reporter assay showed that luciferase activity in DADS- and DATS-treated cells was 2.8- and 3.9-fold higher than that in control cells, respectively (P < 0.05). Again, luciferase activity was not affected by treatment with DAS. Deletion of -2.7 to -2.6 kb in the GSTP promoter region, which contains the GSTP enhancer (GPE) I element, abolished the upregulation of GSTP transcription by DADS and DATS. Deletion of GPE II, however, did not affect the induction of reporter activity. In conclusion, the effectiveness of 3 garlic allyl sulfides on GSTP expression was related to the number of sulfur atoms in the molecules, and GPE I was responsible for this upregulation. PMID:16251611

  11. Cytotoxicity, oxidative stress, and genotoxicity in human hepatocyte and embryonic kidney cells exposed to ZnO nanoparticles

    NASA Astrophysics Data System (ADS)

    Guan, Rongfa; Kang, Tianshu; Lu, Fei; Zhang, Zhiguo; Shen, Haitao; Liu, Mingqi

    2012-10-01

    Traces of zinc oxide nanoparticles (ZnO NPs) used may be found in the liver and kidney. The aim of this study is to determine the optimal viability assay for using with ZnO NPs and to assess their toxicity to human hepatocyte (L02) and human embryonic kidney (HEK293) cells. Cellular morphology, mitochondrial function (MTT assay), and oxidative stress markers (malondialdehyde, glutathione (GSH) and superoxide dismutase (SOD)) were assessed under control and exposed to ZnO NPs conditions for 24 h. The results demonstrated that ZnO NPs lead to cellular morphological modifications, mitochondrial dysfunction, and cause reduction of SOD, depletion of GSH, and oxidative DNA damage. The exact mechanism behind ZnO NPs toxicity suggested that oxidative stress and lipid peroxidation played an important role in ZnO NPs-elicited cell membrane disruption, DNA damage, and subsequent cell death. Our preliminary data suggested that oxidative stress might contribute to ZnO NPs cytotoxicity.

  12. Subtoxic Alterations in Hepatocyte-Derived Exosomes: An Early Step in Drug-Induced Liver Injury?

    PubMed

    Holman, Natalie S; Mosedale, Merrie; Wolf, Kristina K; LeCluyse, Edward L; Watkins, Paul B

    2016-06-01

    Drug-induced liver injury (DILI) is a significant clinical and economic problem in the United States, yet the mechanisms that underlie DILI remain poorly understood. Recent evidence suggests that signaling molecules released by stressed hepatocytes can trigger immune responses that may be common across DILI mechanisms. Extracellular vesicles released by hepatocytes, principally hepatocyte-derived exosomes (HDEs), may constitute one such signal. To examine HDE alterations as a function of drug-induced stress, this work utilized prototypical hepatotoxicant acetaminophen (APAP) in male Sprague-Dawley (SD) rats, SD rat hepatocytes, and primary human hepatocytes. HDE were isolated using ExoQuick precipitation reagent and analyzed by quantification of the liver-specific RNAs albumin and microRNA-122 (miR-122). In vivo, significant elevations in circulating exosomal albumin mRNA were observed at subtoxic APAP exposures. Significant increases in exosomal albumin mRNA were also observed in primary rat hepatocytes at subtoxic APAP concentrations. In primary human hepatocytes, APAP elicited increases in both exosomal albumin mRNA and exosomal miR-122 without overt cytotoxicity. However, the number of HDE produced in vitro in response to APAP did not increase with exosomal RNA quantity. We conclude that significant drug-induced alterations in the liver-specific RNA content of HDE occur at subtoxic APAP exposures in vivo and in vitro, and that these changes appear to reflect selective packaging rather than changes in exosome number. The current findings demonstrate that translationally relevant HDE alterations occur in the absence of overt hepatocellular toxicity, and support the hypothesis that HDE released by stressed hepatocytes may mediate early immune responses in DILI. PMID:26962055

  13. Hepatocyte-like cells derived from human amniotic epithelial cells can be encapsulated without loss of viability or function in vitro.

    PubMed

    Vaghjiani, Vijesh; Vaithilingam, Vijayaganapathy; Saraswati, Indah; Sali, Adnan; Murthi, Padma; Kalionis, Bill; Tuch, Bernard E; Manuelpillai, Ursula

    2014-04-15

    Placenta derived human amniotic epithelial cells (hAEC) are an attractive source of stem cells for the generation of hepatocyte-like cells (HLC) for therapeutic applications to treat liver diseases. During hAEC differentiation into HLC, they become increasingly immunogenic, which may result in immune cell-mediated rejection upon transplantation into allogeneic recipients. Placing cells within devices such as alginate microcapsules can prevent immune cell-mediated rejection. The aim of this study was to investigate the characteristics of HLC generated from hAEC and to examine the effects of encapsulation on HLC viability, gene expression, and function. hAEC were differentiated for 4 weeks and evaluated for hepatocyte-specific gene expression and function. Differentiated cells were encapsulated in barium alginate microcapsules and cultured for 7 days and the effect of encapsulation on cell viability, function, and hepatocyte related gene expression was determined. Differentiated cells performed key functions of hepatocytes including urea synthesis, drug-metabolizing cytochrome P450 (CYP)3A4 activity, indocyanine green (ICG) uptake, low-density lipoprotein (LDL) uptake, and exhibited glutathione antioxidant capacity. A number of hepatocyte-related genes involved in fat, cholesterol, bile acid synthesis, and xenobiotic metabolism were also expressed showing that the hAEC had differentiated into HLC. Upon encapsulation, the HLC remained viable for at least 7 days in culture, continued to express genes involved in fat, cholesterol, bile acid, and xenobiotic metabolism and had glutathione antioxidant capacity. CYP3A4 activity and urea synthesis by the encapsulated HLC were higher than that of monolayer HLC cultures. Functional HLC can be derived from hAEC, and HLC can be encapsulated within alginate microcapsules without losing viability or function in vitro. PMID:24295364

  14. Hepatocyte-Like Cells Derived from Human Amniotic Epithelial Cells Can Be Encapsulated Without Loss of Viability or Function In Vitro

    PubMed Central

    Vaghjiani, Vijesh; Vaithilingam, Vijayaganapathy; Saraswati, Indah; Sali, Adnan; Murthi, Padma; Kalionis, Bill; Tuch, Bernard E.

    2014-01-01

    Placenta derived human amniotic epithelial cells (hAEC) are an attractive source of stem cells for the generation of hepatocyte-like cells (HLC) for therapeutic applications to treat liver diseases. During hAEC differentiation into HLC, they become increasingly immunogenic, which may result in immune cell-mediated rejection upon transplantation into allogeneic recipients. Placing cells within devices such as alginate microcapsules can prevent immune cell-mediated rejection. The aim of this study was to investigate the characteristics of HLC generated from hAEC and to examine the effects of encapsulation on HLC viability, gene expression, and function. hAEC were differentiated for 4 weeks and evaluated for hepatocyte-specific gene expression and function. Differentiated cells were encapsulated in barium alginate microcapsules and cultured for 7 days and the effect of encapsulation on cell viability, function, and hepatocyte related gene expression was determined. Differentiated cells performed key functions of hepatocytes including urea synthesis, drug-metabolizing cytochrome P450 (CYP)3A4 activity, indocyanine green (ICG) uptake, low-density lipoprotein (LDL) uptake, and exhibited glutathione antioxidant capacity. A number of hepatocyte-related genes involved in fat, cholesterol, bile acid synthesis, and xenobiotic metabolism were also expressed showing that the hAEC had differentiated into HLC. Upon encapsulation, the HLC remained viable for at least 7 days in culture, continued to express genes involved in fat, cholesterol, bile acid, and xenobiotic metabolism and had glutathione antioxidant capacity. CYP3A4 activity and urea synthesis by the encapsulated HLC were higher than that of monolayer HLC cultures. Functional HLC can be derived from hAEC, and HLC can be encapsulated within alginate microcapsules without losing viability or function in vitro. PMID:24295364

  15. In vitro oxidative metabolism of cajaninstilbene Acid by human liver microsomes and hepatocytes: involvement of cytochrome p450 reaction phenotyping, inhibition, and induction studies.

    PubMed

    Hua, Xin; Peng, Xiao; Tan, Shengnan; Li, Chunying; Wang, Wei; Luo, Meng; Fu, Yujie; Zu, Yuangang; Smyth, Hugh

    2014-10-29

    Cajaninstilbene acid (CSA, 3-hydroxy-4-prenyl-5-methoxystilbene-2-carboxylic acid), an active constituent of pigeonpea leaves, an important tropical crop, is known for its clinical effects in the treatment of diabetes, hepatitis, and measles and its potential antitumor effect. In this study, the effect of the cytochrome P450 isozymes on the activity of CSA was investigated. Two hydroxylation metabolites were identified in the study. The reaction phenotype study showed that CYP3A4, CYP2C9, and CYP1A2 were the major cytochrome P450 isozymes in the metabolism of CSA. The metabolic food-drug interaction potential was also evaluated in vitro. The effect of CSA inhibition/induction of enzymatic activities of seven drug-metabolizing CYP450 isozymes in vitro was estimated by high-performance liquid chromatography and liquid chromatography-tandem mass spectrometry analytical techniques. CSA showed different inhibitory effects on different isozymes. CSA reversibly inhibited CYP3A4 and CYP2C9 activities in human liver microsomes with IC50 values of 28.3 and 31.3 μM, respectively, but exhibited no inhibition activities to CYP1A2, CYP2A6, CYP2C19, CYP2D6, and CYP2E1. CSA showed a weak effect on CYP450 enzymes in a time-dependent manner. CSA did not substantially induce CYP1A2, CYP2A6, CYP2B6, CYP2E1, CYP2C9, CYP2C19, CYP2D6, or CYP3A4 at concentrations up to 30 μM in primary human hepatocytes. The results of our experiments may be helpful to predict clinically significant food-drug interactions when other drugs are administered in combination with CSA. PMID:25272989

  16. Xeno-sensing activity of the aryl hydrocarbon receptor in human pluripotent stem cell-derived hepatocyte-like cells

    PubMed Central

    Kim, Hye-Min; Kim, Ji-Woo; Choi, Youngjun; Chun, Hang-Suk; Im, Ilkyun; Han, Yong-Mahn; Song, Chang-Woo; Yoon, Seokjoo; Park, Han-Jin

    2016-01-01

    Although hepatocyte-like cells derived from human pluripotent stem cells (hPSC-HLCs) are considered a promising model for predicting hepatotoxicity, their application has been restricted because of the low activity of drug metabolizing enzymes (DMEs). Here we found that the low expression of xenobiotic receptors (constitutive androstane receptor, CAR; and pregnane X receptor, PXR) contributes to the low activity of DMEs in hPSC-HLCs. Most CAR- and PXR-regulated DMEs and transporters were transcriptionally down-regulated in hPSC-HLC. Transcriptional expression of CAR and PXR was highly repressed in hPSC-HLCs, whereas mRNA levels of aryl hydrocarbon receptor (AHR) were comparable to those of adult liver. Furthermore, ligand-induced transcriptional activation was observed only at AHR in hPSC-HLCs. Bisulfite sequencing analysis demonstrated that promoter hypermethylation of CAR and PXR was associated with diminished transcriptional activity in hPSC-HLCs. Treatment with AHR-selective ligands increased the transcription of AHR-dependent target genes by direct AHR-DNA binding at the xenobiotic response element. In addition, an antagonist of AHR significantly inhibited AHR-dependent target gene expression. Thus, AHR may function intrinsically as a xenosensor as well as a ligand-dependent transcription factor in hPSC-HLCs. Our results indicate that hPSC-HLCs can be used to screen toxic substances related to AHR signaling and to identify potential AHR-targeted therapeutics. PMID:26899675

  17. Responses of Nontransformed Human Hepatocytes to Conditional Expression of Full-Length Hepatitis C Virus Open Reading Frame

    PubMed Central

    Tang, Weiliang; Lázaro, Catherine A.; Campbell, Jean S.; Parks, W. Tony; Katze, Michael G.; Fausto, Nelson

    2007-01-01

    Hepatitis C virus (HCV) is a major cause of chronic hepatitis that can lead to cirrhosis and hepatocellular carcinoma. To study the effects of HCV protein expression on host cells, we established conditional expression of the full-length open reading frame (ORF) of an infectious cDNA clone of HCV (genotype 1a, H77 strain) in the nontransformed human hepatocyte line cell HH4 using the ecdysone receptor regulatory system. Treatment with the ecdysone analog ponasterone-A induced tightly regulated and dose-dependent full-length HCV ORF expression and properly processed HCV proteins. HCV Core, NS3, and NS5A colocalized in perinuclear regions and associated with the early endosomal protein EEA1. HCV ORF expression caused marked growth inhibition, increased intracellular reactive oxygen species, up-regulation of glutamate-l-cysteine ligase activity, increased glutathione level, and activation of nuclear factor κB. Although it was not directly cytotoxic, HCV ORF expression sensitized HH4 cells to Fas at certain concentrations but not to tumor necrosis factor-related apoptosis-inducing ligand. HCV ORF expression in HH4 cells up-regulated genes involved in innate immune response/inflammation and oxidative stress responses and down-regulated cell growth-related genes. Expression of HCV ORF in host cells may contribute to HCV pathogenesis by producing oxidative stress and increasing the expression of genes related to the innate immune response and inflammation. PMID:17991716

  18. Contribution of cytochrome P450 and UDT-glucuronosyltransferase to the metabolism of drugs containing carboxylic acid groups: risk assessment of acylglucuronides using human hepatocytes.

    PubMed

    Jinno, Norimasa; Tagashira, Mizuka; Tsurui, Kazuyuki; Yamada, Shizuo

    2014-08-01

    1. In order to evaluate the inhibition activity of 1-aminobenzotriazole (ABT) and (-)-borneol (borneol) against cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT), the substrates of these metabolic enzymes were incubated with ABT and borneol in human hepatocytes. We found that 3 mM ABT and 300 μM borneol were the most suitable experimental levels to specifically inhibit CYP and UGT. 2. Montelukast, mefenamic acid, flufenamic acid, diclofenac, tienilic acid, gemfibrozil, ibufenac and repaglinide were markedly metabolized in human hepatocytes, and the metabolism of gemfibrozil, mefenamic acid and flufenamic acid was inhibited by borneol. With regard to repaglinide, montelukast, diclofenac and tienilic acid, metabolism was inhibited by ABT. Ibufenac was partly inhibited by both inhibitors. Zomepirac, tolmetin, ibuprofen, indomethacin and levofloxacin were moderately metabolized by human hepatocytes, and the metabolism of zomepirac, ibuprofen and indomethacin was equally inhibited by both ABT and borneol. The metabolism of tolmetin was strongly inhibited by ABT, and was also inhibited weakly by borneol. Residual drugs, telmisartan, valsartan, furosemide, naproxen and probenecid were scarcely metabolized. 3. Although we attempted to predict the toxicological risks of drugs containing carboxylic groups from the combination chemical stability and CLint via UGT, the results indicated that this combination was not sufficient and that clinical daily dose is important. PMID:24575896

  19. Transcription Factors and Medium Suitable for Initiating the Differentiation of Human-Induced Pluripotent Stem Cells to the Hepatocyte Lineage.

    PubMed

    Tomizawa, Minoru; Shinozaki, Fuminobu; Motoyoshi, Yasufumi; Sugiyama, Takao; Yamamoto, Shigenori; Ishige, Naoki

    2016-09-01

    Transcription factors and culture media were investigated to determine the condition to initiate the differentiation of human-induced pluripotent stem (iPS) cells most efficiently. The expression of genes in human adult liver was compared with that in 201B7 cells (iPS cells) using cDNA microarray analysis. Episomal plasmids expressing transcription factors were constructed. 201B7 cells were transfected with the episomal plasmids and cultured in ReproFF (feeder-free media maintaining pluripotency), Leibovitz-15 (L15), William's E (WE), or Dulbecco's modified Eagle medium/Nutrient F-12 Ham (DF12) for 7 days. RNA was isolated and subjected to real-time quantitative PCR to analyze the expression of alpha-feto protein (AFP) and albumin. cDNA microarray analysis revealed 16 transcription factors that were upregulated in human adult liver relative to that in 201B7 cells. Episomal plasmids expressing these 16 genes were transfected into 201B7 cells. CCAAT/enhancer-binding protein alpha (CEBPA), CCAAT/enhancer-binding protein beta (CEBPB), forkhead box A1 (FOXA1), and forkhead box A3 (FOXA3) up-regulated AFP and down-regulated Nanog. These four genes were further analyzed. The expression of AFP and albumin was the highest in 201B7 cells transfected with the combination of CEBPA, CEBPB, FOXA1, and FOXA3 and cultured in WE. The combination of CEBPA, CEBPB, FOXA1, and FOXA3 was suitable for 201B7 cells to initiate differentiation to the hepatocyte lineage and WE was the most suitable medium for culture after transfection. J. Cell. Biochem. 117: 2001-2009, 2016. © 2016 Wiley Periodicals, Inc. PMID:26773721

  20. Secretory expression and characterization of a recombinant-deleted variant of human hepatocyte growth factor in Pichia pastoris

    PubMed Central

    Liu, Zhi-Min; Zhao, Hong-Liang; Xue, Chong; Deng, Bing-Bing; Zhang, Wei; Xiong, Xiang-Hua; Yang, Bing-Fen; Yao, Xue-Qin

    2005-01-01

    AIM: To study the secretory expression of human hepatocyte growth factor (hdHGF) gene in Pichia pastoris. METHODS: The full-length gene of human cDNA encoding the deleted variant of hdHGF was cloned by RT-PCR and overlapping-fragment PCR technique using mRNA of human placenta as a template. The cloned hdHGF cDNA was inserted into the Escherichia coli-yeast shuttle vector of pPIC9. The constructed plasmid, pPIC9-hdHGF, was transformed into the GS115 cells of the methylotrophic yeast, P pastoris, using a chemical method. The Mut+ transformants were screened to obtain high-expression strains by the test and analysis of expressed products of shake-flask culture. A secretory form of rhdHGF was made with the aid of the leader peptide sequence of Saccharomyces cerevisiae α-factor. RESULTS: The expressed products, which showed a band of molecular mass of about 80 ku, were observed on 15% SDS-PAGE and identified by Western blotting and N-terminal amino acid sequencing. In the high cell density culture of 5 L fermentor by fed-batch culture protocol, the cell biomass was reached at approximately 135 g (DCW)/L. The productivity of secreted total supernant protein concentration attained a high-level expression of more than 8.0 g/L and the ratio of rhdHGF band area was about 12.3% of the total band area scanned by SDS-PAGE analysis, which estimated that the product of rhdHGF was 500-900 mg/L. CONCLUSION: The P pastoris system represents an attractive tool of generating large quantities of hdHGF for both research and industrial purposes. PMID:16437654

  1. A microtiterplate-based screening assay to assess diverse effects on cytochrome P450 enzyme activities in primary rat hepatocytes by various compounds.

    PubMed

    Schaeffner, I; Petters, J; Aurich, H; Frohberg, P; Christ, B

    2005-02-01

    During the development of potential drugs it is useful to identify pharmacological and/or toxicological side effects of a compound as early as possible in order to exclude them from further development for reasons of time and cost. Activation or inactivation of members of the cytochrome P450-dependent monooxygenase system (CYP450) might indicate potential undesired effects of a given compound. However, results using CYP450 assay systems are often inconsistent because of different experimental settings. Therefore, it was the goal of the present study to optimize the CYP450 assay in primary rat hepatocytes with respect to the time point of addition of and duration of exposure to alpha-naphthoflavone (ANF) and beta-naphthoflavone (BNF) as well as trans-resveratrol (RES), which have well-described stimulatory and inhibitory effects on CYP450 enzymes of the 1A and 2B family, respectively. Hepatocytes were also treated with putative lipoxygenase (LOX)/cyclooxygenase (COX) inhibitors with unknown impact on CYP450 enzyme activity in order to detect potential side effects. Cells were cultured for up to 7 days on 96-well microtiter plates, and enzyme activity was determined by a conventional fluorescence spectroscopy assay. ANF and BNF, given to the cells after 4 days of culture, stimulated CYP1A and 2B activities significantly in a concentration-dependent fashion after long-term exposure for at least 1 day. However, during short-term exposure for 1-6 h, CYP1A activity was inhibited, while CYP2B was increased weakly by ANF but not BNF. RES inhibited CYP1A activity during short- and long-term exposure without affecting CYP2B activity. From the results it was concluded that primary rat hepatocytes should be cultured for at least 3-4 days but no longer prior to the assay. The assay should be performed at two different time points of exposure, i.e., 6 h for short-term and 24 h for long-term exposure. The compounds under investigation should be applied at two different

  2. Mixed-ligand copper(II) complexes activate aryl hydrocarbon receptor AhR and induce CYP1A genes expression in human hepatocytes and human cell lines.

    PubMed

    Kubešová, Kateřina; Dořičáková, Aneta; Trávníček, Zdeněk; Dvořák, Zdeněk

    2016-07-25

    The effects of four copper(II) mixed-ligand complexes [Cu(qui1)(L)]NO3·H2O (1-3) and [Cu(qui2)(phen)]NO3 (4), where qui1=2-phenyl-3-hydroxy-4(1H)-quinolinone, Hqui2=2-(4-amino-3,5-dichlorophenyl)-N-propyl-3-hydroxy-4(1H)-quinolinone-7-carboxamide, L=1,10-phenanthroline (phen) (1), 5-methyl-1,10-phenanthroline (mphen) (2), bathophenanthroline (bphen) (3), on transcriptional activities of steroid receptors, nuclear receptors and xenoreceptors have been studied. The complexes (1-4) did not influence basal or ligand-inducible activities of glucocorticoid receptor, androgen receptor, thyroid receptor, pregnane X receptor and vitamin D receptor, as revealed by gene reporter assays. The complexes 1 and 2 dose-dependently induced luciferase activity in stable gene reporter AZ-AhR cell line, and this induction was reverted by resveratrol, indicating involvement of aryl hydrocarbon receptor (AhR) in the process. The complexes 1, 2 and 3 induced CYP1A1 mRNA in LS180 cells and CYP1A1/CYP1A2 in human hepatocytes through AhR. Electrophoretic mobility shift assay EMSA showed that the complexes 1 and 2 transformed AhR in its DNA-binding form. Collectively, we demonstrate that the complexes 1 and 2 activate AhR and induce AhR-dependent genes in human hepatocytes and cancer cell lines. In conclusion, the data presented here might be of toxicological importance, regarding the multiple roles of AhR in human physiology and pathophysiology. PMID:27180721

  3. Different AhR binding sites of diterpenoid ligands from Andrographis paniculata caused differential CYP1A1 induction in primary culture in mouse hepatocytes.

    PubMed

    Chatuphonprasert, Waranya; Remsungnen, Tawun; Nemoto, Nobuo; Jarukamjorn, Kanokwan

    2011-12-01

    Andrographis paniculata has been employed as a folklore remedy. Andrographolide (Andro), 14-deoxy-11,12-didehydroandrographolide (DHA), andrographiside (AS), and neoandrographolide (Neo), are major diterpenoids isolated from this plant. In the present study, influence of the four diterpenoids on CYP1A1 mRNA expression was investigated in primary cultured mouse hepatocytes. Additionally, binding of these compounds to aryl hydrocarbon receptor (AhR) was examined using molecular docking analysis to clarify mechanism of CYP1A1 induction. Andro and DHA induced CYP1A1 expression by itself, and co-treatment with a CYP1A1 inducer (BNF, beta-naphthoflavone) showed a synergistic increase of CYP1A1 expression. Andro demonstrated higher enhancing activity than DHA at every similar concentration. On the other hand, Neo suppressed BNF-induced CYP1A1 expression, but AS did not modify the induction. Results from molecular docking analysis of BNF and four diterpenoids on ligand binding domain of AhR were consistent with levels of CYP1A1 mRNA expressions. Furthermore, difference of binding sites of BNF in the presence of diterpenoids might affect the synergism or inhibition of CYP1A1 expression. These results suggest that use of A. paniculata as a health supplement should be concerned in term of herb-drugs interactions or risk of carcinogenesis, according to its ability to influence CYP1A1 expression. PMID:21963808

  4. Modulation of ultraviolet light-, ethyl methanesulfonate-, and 7,12-dimethylbenz(A)anthracene-induced unscheduled DNA synthesis by retinol and retinoic acid in the primary rat hepatocyte

    SciTech Connect

    Budroe, J.D.; Shaddock, J.G.; Casciano, D.A.

    1987-01-01

    The effects of retinol and retinoic acid on unscheduled DNA synthesis (UDS) in primary Sprague-Dawley rat hepatocytes were studied in the presence and absence of know chemical and physical mutagens. Neither retinol or retinoic acid caused a significant increase in UDS over solvent control at concentrations ranging from 1 ..mu..M to 50 ..mu..M. Retinol and retinoic acid did not significantly affect 200..mu..g/mL ethyl methanesulfonate (EMS)- or 32 J/m/sup 2/ ultraviolet light (UV)-induced UDS at concentrations ranging from 1..mu..M to 50 ..mu..M. In contrast, retinol and retinoic acid significantly inhibited 2.5 ..mu..g/mL and 5.0 ..mu..g/mL 7,12-dimethyl-benz(a)-anthracene(DMBA)-induced UDS at concentrations of 1..mu..M or greater. Retinol-and retinoic acid-induced hepatocytotoxicity was studied in vitro using lactate dehydrogenase (LDH) release as an indicator of cytoxicity. Neither retinol nor retinoic acid caused significant increases in LDH release over solvent control 3 hours after treatment, whereas retinol caused a biologically significant increase in LDH release 24 hours posttreatment at concentrations of 50 ..mu..M and 100 ..mu..M. These data suggest that nontoxic concentrations of retinol and retinoic acid do not inhibit the DNA excision repair process but apparently affect the effective DNA adduct load due to the ultimate species of DMBA metabolite responsible for hepatocellular DNA damage.

  5. Modulation of ultraviolet light-, ethyl methanesulfonate-, and 7,12-dimethylbenz(a)anthracene-induced unscheduled DNA synthesis by retinol and retinoic acid in the primary rat hepatocyte

    SciTech Connect

    Budroe, J.D.; Shaddock, J.G.; Casciano, D.A.

    1987-01-01

    The effects of retinol and retinoic acid on unscheduled DNA synthesis (UDS) in primary Sprague-Dawley rat hepatocytes were studied in the presence and absence of known chemical and physical mutagens. Neither retinol nor retinoic acid caused a significant increase in UDS over solvent control at concentrations ranging from 1 microM to 50 microM. Retinol and retinoic acid did not significantly affect 200 micrograms/mL ethyl methanesulfonate(EMS)- or 32 J/m2 ultraviolet light(UV)-induced UDS at concentrations ranging from 1 microM to 50 microM. In contrast, retinol and retinoic acid significantly inhibited 2.5 micrograms/mL and 5.0 micrograms/mL 7,12-dimethyl-benz(a)anthracene(DMBA)-induced UDS at concentrations of 1 microM or greater. Retinol- and retinoic acid-induced hepatocytotoxicity was studied in vitro using lactate dehydrogenase (LDH) release as an indicator of cytoxicity. Neither retinol nor retinoic acid caused significant increases in LDH release over solvent control 3 hours after treatment, whereas retinol caused a biologically significant increase in LDH release 24 hours posttreatment at concentrations of 50 microM and 100 microM. These data suggest that nontoxic concentrations of retinol and retinoic acid do not inhibit the DNA excision repair process but apparently affect the effective DNA adduct load due to the ultimate species of DMBA metabolite responsible for hepatocellular DNA damage.

  6. Differentiation of hepatocytes from pluripotent stem cells

    PubMed Central

    Mallanna, Sunil K.

    2014-01-01

    Differentiation of human embryonic stem (ES) and induced pluripotent stem (iPS) cells into hepatocyte-like cells provides a platform to study the molecular basis of human hepatocyte differentiation, to develop cell culture models of liver disease, and to potentially provide hepatocytes for treatment of end-stage liver disease. Additionally, hepatocyte-like cells generated from human pluripotent stem cells could serve as platforms for drug discovery, determination of pharmaceutical induced hepatotoxicity, and evaluation of idiosyncratic drug-drug interactions. Here, we describe a step-wise protocol previously developed in our laboratory that facilitates the highly efficient and reproducible differentiation of human pluripotent stem cells into hepatocyte-like cells. Our protocol uses defined culture conditions and closely recapitulates key developmental events that are found to occur during hepatogenesis. PMID:24510789

  7. EVALUATION OF PERFLUOROALKYL ACID ACTIVITY USING PRIMARY MOUSE AND HUMAN HEPATOCYTES

    EPA Science Inventory

    While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is know about the biological activity of other environmental perfluoroalkyl acids (pFAAs). Using a transient transfection assay developed in COS-l cells, our group has previ...

  8. Flame retardant BDE-47 effectively activates nuclear receptor CAR in human primary hepatocytes

    EPA Science Inventory

    Polybrominated diphenyl ether BDE-47 (2,2’,4,4’-tetrabromodiphenyl ether) is a thyroid hormone disruptor in mice; hepatic induction of various metabolic enzymes and transporters has been suggested as the mechanism for this disruption. Utilizing Car-/- and Pxr-/- mice as well as h...

  9. INTERINDIVIDUAL VARIATION IN THE METABOLISM OF ARSENIC IN CULTURED PRIMARY HUMAN HEPATOCYTES

    EPA Science Inventory

    Liver is a prime site for conversion of inorganic arsenic (iAs) to methylated metabolites, including methylarsenicals (MAs) and dimethylarsenicals (DMAs). To assess interindividual variation in the capacity of liver to metabolize iAs, we examined the metabolic fate of arsenite (...

  10. Evaluating Thyroxine Metabolism and Transport in Primary Rat and Human Hepatocytes Following BDE 47 Exposure

    EPA Science Inventory

    Polybrominated diphenyl ethers (PBDEs) are a class of flame retardants used in various consumer products including polyurethane foam, electronics, and textile coating. 2,2’,4,4’-Tetrabromodiphenyl ether (BDE 47) is the predominant PBDE congener accounting for half of...

  11. Evaluation of Perfluoroalkyl Acid Activity Using Primary Mouse and Human Hepatocytes.

    EPA Science Inventory

    While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is known about the biological activity of other perfluoroalkyl acids (PFAAs) in the environment. Using a transient transfection assay developed in COS-1 cells, our group h...

  12. Cytotoxicity, intracellular localization and exocytosis of citrate capped and PEG functionalized gold nanoparticles in human hepatocyte and kidney cells.

    PubMed

    Tlotleng, Nonhlanhla; Vetten, Melissa A; Keter, Frankline K; Skepu, Amanda; Tshikhudo, Robert; Gulumian, Mary

    2016-08-01

    Surface-modified gold nanoparticles (AuNPs) are nanomaterials that hold promise in drug delivery applications. In this study, the cytotoxicity, uptake, intracellular localization, and the exocytosis of citrate-stabilized (Cit-AuNP) and polyethylene glycol (PEG)-modified gold nanoparticles with the carboxyl (COOH) terminal functional group were assessed in human embryonic kidney (HEK 293) and the human caucasian hepatocytes carcinoma (Hep G2) cell systems, representing two major accumulation sites for AuNPs. The zeta (ζ)-potential measurements confirmed the negative surface charge of the AuNPs in water and in cell growth medium. The transmission electron microscopy confirmed the size and morphology of the AuNPs. Both types of AuNPs were shown to induce cytotoxic effects in cells. The Hep G2 cells were more sensitive cell type, with the COOH-PEG-AuNPs inducing the highest toxicity at higher concentrations. Dark field microscopy and TEM images revealed that the AuNPs were internalized in cells, mostly as agglomerates. TEM micrographs further revealed that the AuNPs were confined as agglomerates inside vesicle-like compartments, likely to be endosomal and lysosomal structures as well as in the cytosol, mostly as individual particles. The AuNPs were shown to remain in cellular compartments for up to 3 weeks, but thereafter, clearance of the gold nanoparticles from the cells by exocytosis was evident. The results presented in this study may therefore give an indication on the fate of AuNPs on long-term exposure to cells and may also assist in safety evaluation of AuNPs. PMID:27184667

  13. Preferential Glutathione Conjugation of a Reverse Diol Epoxide Compared with a Bay Region Diol Epoxide of Benzo[a]pyrene in Human Hepatocytes

    PubMed Central

    Upadhyaya, Pramod; Hochalter, J. Bradley; Balbo, Silvia; McIntee, Edward J.

    2010-01-01

    Many studies have examined the relationship between polymorphisms in glutathione S-transferase genes and cancer in people exposed to polycyclic aromatic hydrocarbons (PAH) such as benzo[a]pyrene (BaP), but the results to date have been modest. Missing from these studies has been an exploration of the formation of the appropriate glutathione conjugates in humans. We incubated human hepatocytes from 10 donors with racemic anti-BaP-7,8-diol-9,10-epoxide (BPDE), believed to be a major ultimate carcinogen of BaP, or with the noncarcinogenic reverse diol epoxide, racemic anti-BaP-9,10-diol-7,8-epoxide (rev-BPDE). Incubations were carried out for 12 or 24 h. We used high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry-selected reaction monitoring at m/z 464 → m/z 317 to analyze the incubation mixtures for the mercapturic acid products that would result from glutathione conjugation. The standard mercapturic acids were synthesized by reaction of BPDE or rev-BPDE with N-acetylcysteine. We obtained convincing evidence in human hepatocytes for mercapturic acid formation from rev-BPDE in all 10 samples, in amounts up to 17 pmol/ml. However, we could detect mercapturic acids from BPDE in only 1 of 10 samples (0.05 pmol/ml). Taken together with our similar previous results of analyses of phenanthrene metabolites in human hepatocytes and human urine, the results of this study indicate that conjugation of BPDE with glutathione is a minor pathway in humans, indicating that glutathione S-transferase genotyping is not an effective method for assessing risk of PAH-induced cancer in humans, at least with respect to the diol epoxide pathway of PAH carcinogenesis. PMID:20547966

  14. Recent advances in 2D and 3D in vitro systems using primary hepatocytes, alternative hepatocyte sources and non-parenchymal liver cells and their use in investigating mechanisms of hepatotoxicity, cell signaling and ADME.

    PubMed

    Godoy, Patricio; Hewitt, Nicola J; Albrecht, Ute; Andersen, Melvin E; Ansari, Nariman; Bhattacharya, Sudin; Bode, Johannes Georg; Bolleyn, Jennifer; Borner, Christoph; Böttger, Jan; Braeuning, Albert; Budinsky, Robert A; Burkhardt, Britta; Cameron, Neil R; Camussi, Giovanni; Cho, Chong-Su; Choi, Yun-Jaie; Craig Rowlands, J; Dahmen, Uta; Damm, Georg; Dirsch, Olaf; Donato, María Teresa; Dong, Jian; Dooley, Steven; Drasdo, Dirk; Eakins, Rowena; Ferreira, Karine Sá; Fonsato, Valentina; Fraczek, Joanna; Gebhardt, Rolf; Gibson, Andrew; Glanemann, Matthias; Goldring, Chris E P; Gómez-Lechón, María José; Groothuis, Geny M M; Gustavsson, Lena; Guyot, Christelle; Hallifax, David; Hammad, Seddik; Hayward, Adam; Häussinger, Dieter; Hellerbrand, Claus; Hewitt, Philip; Hoehme, Stefan; Holzhütter, Hermann-Georg; Houston, J Brian; Hrach, Jens; Ito, Kiyomi; Jaeschke, Hartmut; Keitel, Verena; Kelm, Jens M; Kevin Park, B; Kordes, Claus; Kullak-Ublick, Gerd A; LeCluyse, Edward L; Lu, Peng; Luebke-Wheeler, Jennifer; Lutz, Anna; Maltman, Daniel J; Matz-Soja, Madlen; McMullen, Patrick; Merfort, Irmgard; Messner, Simon; Meyer, Christoph; Mwinyi, Jessica; Naisbitt, Dean J; Nussler, Andreas K; Olinga, Peter; Pampaloni, Francesco; Pi, Jingbo; Pluta, Linda; Przyborski, Stefan A; Ramachandran, Anup; Rogiers, Vera; Rowe, Cliff; Schelcher, Celine; Schmich, Kathrin; Schwarz, Michael; Singh, Bijay; Stelzer, Ernst H K; Stieger, Bruno; Stöber, Regina; Sugiyama, Yuichi; Tetta, Ciro; Thasler, Wolfgang E; Vanhaecke, Tamara; Vinken, Mathieu; Weiss, Thomas S; Widera, Agata; Woods, Courtney G; Xu, Jinghai James; Yarborough, Kathy M; Hengstler, Jan G

    2013-08-01

    This review encompasses the most important advances in liver functions and hepatotoxicity and analyzes which mechanisms can be studied in vitro. In a complex architecture of nested, zonated lobules, the liver consists of approximately 80 % hepatocytes and 20 % non-parenchymal cells, the latter being involved in a secondary phase that may dramatically aggravate the initial damage. Hepatotoxicity, as well as hepatic metabolism, is controlled by a set of nuclear receptors (including PXR, CAR, HNF-4α, FXR, LXR, SHP, VDR and PPAR) and signaling pathways. When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes. An understanding of these changes is crucial for a correct interpretation of in vitro data. The possibilities and limitations of the most useful liver in vitro systems are summarized, including three-dimensional culture techniques, co-cultures with non-parenchymal cells, hepatospheres, precision cut liver slices and the isolated perfused liver. Also discussed is how closely hepatoma, stem cell and iPS cell-derived hepatocyte-like-cells resemble real hepatocytes. Finally, a summary is given of the state of the art of liver in vitro and mathematical modeling systems that are currently used in the pharmaceutical industry with an emphasis on drug metabolism, prediction of clearance, drug interaction, transporter studies and hepatotoxicity. One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation. Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun. PMID:23974980

  15. Transcriptome analysis reveals a classical interferon signature induced by IFNλ4 in human primary cells.

    PubMed

    Lauber, C; Vieyres, G; Terczyńska-Dyla, E; Anggakusuma; Dijkman, R; Gad, H H; Akhtar, H; Geffers, R; Vondran, F W R; Thiel, V; Kaderali, L; Pietschmann, T; Hartmann, R

    2015-09-01

    The IFNL4 gene is negatively associated with spontaneous and treatment-induced clearance of hepatitis C virus infection. The activity of IFNλ4 has an important causal role in the pathogenesis, but the molecular details are not fully understood. One possible reason for the detrimental effect of IFNλ4 could be a tissue-specific regulation of an unknown subset of genes. To address both tissue and subtype specificity in the interferon response, we treated primary human hepatocytes and airway epithelial cells with IFNα, IFNλ3 or IFNλ4 and assessed interferon mediated gene regulation using transcriptome sequencing. Our data show a surprisingly similar response to all three subtypes of interferon. We also addressed the tissue specificity of the response, and identified a subset of tissue-specific genes. However, the interferon response is robust in both tissues with the majority of the identified genes being regulated in hepatocytes as well as airway epithelial cells. Thus we provide an in-depth analysis of the liver interferon response seen over an array of interferon subtypes and compare it to the response in the lung epithelium. PMID:26066369

  16. Leflunomide or A77 1726 protect from acetaminophen-induced cell injury through inhibition of JNK-mediated mitochondrial permeability transition in immortalized human hepatocytes

    SciTech Connect

    Latchoumycandane, Calivarathan; Seah, Quee Ming; Tan, Rachel C.H.; Sattabongkot, Jetsumon; Beerheide, Walter; Boelsterli, Urs A. . E-mail: phcbua@nus.edu.sg

    2006-11-15

    Leflunomide, a disease-modifying anti-rheumatic drug, protects against T-cell-mediated liver injury by poorly understood mechanisms. The active metabolite of leflunomide, A77 1726 (teriflunomide) has been shown to inhibit stress-activated protein kinases (JNK pathway), which are key regulators of mitochondria-mediated cell death. Therefore, we hypothesized that leflunomide may protect from drugs that induce the mitochondrial permeability transition (mPT) by blocking the JNK signaling pathway. To this end, we exposed cultured immortalized human hepatocytes (HC-04) to the standard protoxicant drug acetaminophen (APAP), which induces CsA-sensitive mPT-mediated cell death. We determined the effects of leflunomide on the extent of APAP-induced hepatocyte injury and the upstream JNK-mediated mitochondrial signaling pathways. We found that leflunomide or A77 1726 concentration-dependently protected hepatocytes from APAP (1 mM)-induced mitochondrial permeabilization and lethal cell injury. This was not due to proximal inhibition of CYP-catalyzed APAP bioactivation to its thiol-reactive metabolite. Instead, we demonstrate that leflunomide (20 {mu}M) inhibited the APAP-induced early (3 h) activation (phosphorylation) of JNK1/2, thus inhibiting phosphorylation of the anti-apoptotic protein Bcl-2 and preventing P-Bcl-2-mediated induction of the mPT. This greatly attenuated mitochondrial cytochrome c release, which we used as a marker for mitochondrial permeabilization. The specific JNK2 inhibitor SP600125 similarly protected from APAP-induced cell death. In conclusion, these findings are consistent with our hypothesis that leflunomide protects from protoxicant-induced hepatocyte injury by inhibiting JNK signaling and preventing mPT induction.

  17. Investigation of Testosterone, Androstenone, and Estradiol Metabolism in HepG2 Cells and Primary Culture Pig Hepatocytes and Their Effects on 17βHSD7 Gene Expression

    PubMed Central

    Chen, Gang; Li, Sicong; Dong, Xinxing; Bai, Ying; Chen, Ailiang; Yang, Shuming; Fang, Meiying; Zamaratskaia, Galia; Doran, Olena

    2012-01-01

    Steroid metabolism is important in various species. The accumulation of androgen metabolite, androstenone, in pig adipose tissue is negatively associated with pork flavor, odour and makes the meat unfit for human consumption. The 17β-hydroxysteroid dehydrogenase type 7 (17βHSD7) expressed abundantly in porcine liver, and it was previously suggested to be associated with androstenone levels. Understanding the enzymes and metabolic pathways responsible for androstenone as well as other steroids metabolism is important for improving the meat quality. At the same time, metabolism of steroids is known to be species- and tissue-specific. Therefore it is important to investigate between-species variations in the hepatic steroid metabolism and to elucidate the role of 17βHSD7 in this process. Here we used an effective methodological approach, liquid chromatography coupled with mass spectrometry, to investigate species-specific metabolism of androstenone, testosterone and beta-estradiol in HepG2 cell line, and pig cultured hepatocytes. Species- and concentration-depended effect of steroids on 17βHSD7 gene expression was also investigated. It was demonstrated that the investigated steroids can regulate the 17βHSD7 gene expression in HepG2 and primary cultured porcine hepatocytes in a concentration-dependent and species-dependent pattern. Investigation of steroid metabolites demonstrated that androstenone formed a 3′-hydroxy compound 3β-hydroxy-5α-androst-16-ene. Testosterone was metabolized to 4-androstene-3,17-dione. Estrone was found as the metabolite for β-estradiol. Inhibition study with 17βHSD inhibitor apigenin showed that apigenin didn’t affect androstenone metabolism. Apigenin at high concentration (50 µM) tends to inhibit testosterone metabolism but this inhibition effect was negligible. Beta-estradiol metabolism was notably inhibited with apigenin at high concentration. The study also established that the level of testosterone and

  18. Burkholderia pseudomallei rpoS mediates iNOS suppression in human hepatocyte (HC04) cells

    PubMed Central

    Sanongkiet, Sucharat; Ponnikorn, Saranyoo; Udomsangpetch, Rachanee; Tungpradabkul, Sumalee

    2016-01-01

    Burkholderia pseudomallei is an intracellular Gram-negative bacterial pathogen and the causative agent of melioidosis, a widespread disease in Southeast Asia. Reactive nitrogen, in an intermediate form of nitric oxide (NO), is one of the first lines of defense used by host cells to eliminate intracellular pathogens, through the stimulation of inducible nitric oxide synthase (iNOS). Studies in phagocytotic cells have shown that the iNOS response is muted in B. pseudomallei infection, and implicated the rpoS sigma factor as a key regulatory factor mediating suppression. The liver is a main visceral organ affected by B. pseudomallei, and there is little knowledge about the interaction of liver cells and B. pseudomallei. This study investigated the induction of iNOS, as well as autophagic flux and light-chain 3 (LC3) localization in human liver (HC04) cells in response to infection with B. pseudomallei and its rpoS deficient mutant. Results showed that the rpoS mutant was unable to suppress iNOS induction and that the mutant showed less induction of autophagy and lower co-localization with LC3, and this was coupled with a lower intracellular growth rate. Combining these results suggest that B. pseudomallei rpoS is an important factor in establishing infection in liver cells. PMID:27324398

  19. Burkholderia pseudomallei rpoS mediates iNOS suppression in human hepatocyte (HC04) cells.

    PubMed

    Sanongkiet, Sucharat; Ponnikorn, Saranyoo; Udomsangpetch, Rachanee; Tungpradabkul, Sumalee

    2016-08-01

    Burkholderia pseudomallei is an intracellular Gram-negative bacterial pathogen and the causative agent of melioidosis, a widespread disease in Southeast Asia. Reactive nitrogen, in an intermediate form of nitric oxide (NO), is one of the first lines of defense used by host cells to eliminate intracellular pathogens, through the stimulation of inducible nitric oxide synthase (iNOS). Studies in phagocytotic cells have shown that the iNOS response is muted in B. pseudomallei infection, and implicated the rpoS sigma factor as a key regulatory factor mediating suppression. The liver is a main visceral organ affected by B. pseudomallei, and there is little knowledge about the interaction of liver cells and B. pseudomallei This study investigated the induction of iNOS, as well as autophagic flux and light-chain 3 (LC3) localization in human liver (HC04) cells in response to infection with B. pseudomallei and its rpoS deficient mutant. Results showed that the rpoS mutant was unable to suppress iNOS induction and that the mutant showed less induction of autophagy and lower co-localization with LC3, and this was coupled with a lower intracellular growth rate. Combining these results suggest that B. pseudomallei rpoS is an important factor in establishing infection in liver cells. PMID:27324398

  20. Antioxidant and Preventive Effects of Extract from Nymphaea candida Flower on In Vitro Immunological Liver Injury of Rat Primary Hepatocyte Cultures

    PubMed Central

    Zhao, Jun; Liu, Tao; Ma, Long; Yan, Ming; Gu, Zhengyi; Huang, Yi; Xu, Fang; Zhao, Yu

    2011-01-01

    Nymphaea candida is traditional Uighur medicine that is commonly used to treat head pains, cough, hepatitis and hypertension in Xinjiang of China. In this article, the extract of N. candida was measured for antioxidant activity, using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals scavenging assay and reducing power determination, and compared with those of the positive controls of butylated hydroxytoluene (BHT) and gallic acid (GA). The active extract was further purified by liquid-liquid partition to afford four fractions, of which the ethyl acetate-soluble (EA) fraction (NCE) exhibited the strongest antioxidant capacity with IC50 value of 12.6 μg/mL for DPPH. Thirteen phenolic compounds were isolated from this fraction, and they all showed significant antioxidant activities in DPPH model system. Furthermore, NCE showed potent antioxidant capacity with IC50 value of 59.32 μg/mL, 24.48 μg/mL and 86.85 μg/mL, for O2−, ·OH and H2O2 radicals, respectively. Moreover, NCE on BCG plus LPS-induced immunological liver injury was evaluated using primary cultured rat hepatocytes. NCE produced significant hepatoprotective effects as evidenced by decreased supernatant enzyme activities (AST—aspartate transaminase, P <  .01; ALT—alanine transferase, P <  .01) and nitric oxide (NO, P <  .01) production. These results revealed the in vitro antioxidant and hepatoprotective activities of NCE against immunological liver injury. Further investigations are necessary to verify these activities in vivo. PMID:19196740