Science.gov

Sample records for human liver chlordecone

  1. Chlordecone (Kepone)

    Integrated Risk Information System (IRIS)

    Chlordecone ( Kepone ) ; CASRN 143 - 50 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcino

  2. Ultra-trace quantification method for chlordecone in human fluids and tissues.

    PubMed

    Bichon, Emmanuelle; Guiffard, Ingrid; Vénisseau, Anaïs; Marchand, Philippe; Antignac, Jean-Philippe; Le Bizec, Bruno

    2015-08-21

    Chlordecone is an organochlorine pesticide (OCP) considered as a Persistent Organic Pollutant (POP) as it persists in the environment, bio-accumulates through the food web, causes adverse effects to human health and the environment and transports across international boundaries far from its sources. The atypical physico-chemical properties of chlordecone make its inclusion in classical analytical approaches non applicable. The aim of our work was to include chlordecone in a multi organochlorine residue method preventing any degradation during the analytical process and thus allowing quantification at ppt (ngkg(-1) or ngL(-1)) levels for a wide range of OCPs in breast milk, human serum and adipose tissue. After GC-HRMS vs. MS/MS and EI vs. APCI comparisons, the major improvement in terms of sensitivity was found in decreasing the length and film thickness of the gas chromatography column. Thanks to a linear correlation between relative response and quantity of chlordecone injected, LC-(ESI-)-MS/MS was finally preferred. An acetonitrile based gradient optimized on a C30 coreshell HPLC column has led to reaching limits of quantification as low as 8ngL(-1), 25pgmL(-1) and 0.2ngg(-1) fat for breast milk, serum and adipose tissue, respectively, allowing multiresidue OCP quantification at concentration levels compatible with biomonitoring purposes and pre-requisites. PMID:26184709

  3. Organochlorine (chlordecone) uptake by root vegetables.

    PubMed

    Florence, Clostre; Philippe, Letourmy; Magalie, Lesueur-Jannoyer

    2015-01-01

    Chlordecone, an organochlorine insecticide, continues to pollute soils in the French West Indies. The main source of human exposure to this pollutant is food. Root vegetables, which are staple foods in tropical regions, can be highly contaminated and are thus a very effective lever for action to reduce consumer exposure. We analyzed chlordecone contamination in three root vegetables, yam, dasheen and sweet potato, which are among the main sources of chlordecone exposure in food in the French West Indies. All soil types do not have the same potential for the contamination of root vegetables, allophanic andosols being two to ten times less contaminating than non-allophanic nitisols and ferralsols. This difference was only partially explained by the higher OC content in allophanic soils. Dasheen corms were shown to accumulate more chlordecone than yam and sweet potato tubers. The physiological nature of the root vegetable may explain this difference. Our results are in good agreement with the hypothesis that chlordecone uptake by root vegetables is based on passive and diffusive processes and limited by transport and dilution during growth.

  4. Chlordecone impairs Na(+)-stimulated L-( sup 3 H)glutamate transport and mobility of 16-doxyl stearate in rat liver plasma membrane vesicles

    SciTech Connect

    Rochelle, L.G.; Miller, T.L.; Curtis, L.R. )

    1990-09-01

    Chlordecone (CD) treatment of rat liver plasma membranes (LPM) provided in vitro evidence for mechanisms of in vivo liver dysfunction caused by CD. LPM preparations enriched 14- to 19-fold in the bile canalicular markers gamma-glutamyl transpeptidase, alkaline phosphatase, and leucine aminopeptidase were isolated from male Sprague-Dawley rats. CD inhibited the bile canalicular-specific active transport of Na(+)-stimulated L-({sup 3}H)glutamate in LPM vesicles. CD (0.08 and 0.5 mumol/mg protein) reduced both the initial velocity and the maximum level of Na(+)-stimulated L-(3H)glutamate uptake without significantly reducing Na(+)-independent uptake. In vitro treatment of LPM with CD (0.2-1.0 mumols/mg protein) also reduced the mobility of a 16-doxyl stearate spin label probe in a concentration-dependent manner. No change in mobility was apparent at CD concentrations below 0.2 mumol/mg protein. These results demonstrated that CD impaired a bile canalicular-specific transport system and induced liver plasma membrane perturbation. Na(+)-stimulated L-({sup 3}H)glutamate uptake was more sensitive to CD than was detectable immobilization of the spin label probe.

  5. Chlordecone altered hepatic disposition of [{sup 14}C]cholesterol and plasma cholesterol distribution but not SR-BI or ABCG8 proteins in livers of C57BL/6 mice

    SciTech Connect

    Lee, Junga; Scheri, Richard C.; Curtis, Lawrence R.

    2008-06-15

    Organochlorine (OC) insecticides continue to occur in tissues of humans and wildlife throughout the world although they were banned in the United States a few decades ago. Low doses of the OC insecticide chlordecone (CD) alter hepatic disposition of lipophilic xenobiotics and perturb lipid homeostasis in rainbow trout, mice and rats. CD pretreatment altered tissue and hepatic subcellular distribution of exogenous [{sup 14}C]cholesterol (CH) equivalents 4 and 16 h after a bolus intraperitoneal (ip) injection of 5 ml corn oil/kg that contained 10 mg CH/kg. CD pretreatment altered tissue distribution of exogenously administered [{sup 14}C]CH by decreased hepatic and renal accumulation, and increased biliary excretion up to 300%. Biliary excretion of polar [{sup 14}C]CH metabolites was not altered by CD. CD pretreatment decreased subcellular distribution of [{sup 14}C]CH equivalents in hepatic cytosol and microsomes and lipoprotein-rich fraction-to-homogenate ratio. CD pretreatment increased the ratio of [{sup 14}C]CH equivalents in high density lipoprotein (HDL) to that in plasma and reduced [{sup 14}C]CH equivalents in the non-HDL fraction 4 h after a bolus lipid dose. CD pretreatment increased plasma non-HDL total CH by 80% 4 h after a bolus lipid dose. Scavenger receptor class B type I (SR-BI) and ATP-binding cassette transporter G8 (ABCG8) proteins were quantified by western blotting in hepatic membranes from control and CD treated mice. Liver membrane contents of SR-BI and ABCG8 proteins were unchanged by CD pretreatment. The data demonstrated that a single dose of CD altered CH homeostasis and lipoprotein metabolism.

  6. Mice with human livers.

    PubMed

    Grompe, Markus; Strom, Stephen

    2013-12-01

    Animal models are used to study many aspects of human disease and to test therapeutic interventions. However, some very important features of human biology cannot be replicated in animals, even in nonhuman primates or transgenic rodents engineered with human genes. Most human microbial pathogens do not infect animals and the metabolism of many xenobiotics is different between human beings and animals. The advent of transgenic immune-deficient mice has made it possible to generate chimeric animals harboring human tissues and cells, including hepatocytes. The liver plays a central role in many human-specific biological processes and mice with humanized livers can be used to model human metabolism, liver injury, gene regulation, drug toxicity, and hepatotropic infections.

  7. Effects of chlordecone and chlordecone alcohol on isolated ovine erythrocytes

    SciTech Connect

    Soileau, S.D.

    1986-01-01

    Chlordecone (CHLO, 1-30 uM) and chlordecone alcohol (CHLO ALC, 1-23 uM) altered the permeability of isolated ovine erythrocytes (OE) as evidenced by a concentration- and time-dependent induction of K/sup +/ efflux and hemolysis. Hemolysis, but no K/sup +/ efflux, was markedly delayed when OE were suspended in isotonic sucrose. Low concentrations of both compounds (1-4 uM) protected OE against hypotonic hemolysis. Neither CHLO (30 uM) nor CHLO ALC (23 uM) induced the release of trapped K/sup +/ from KSCN-loaded, OE-lipid, unilamellar liposomes. CHLO- and CHLO ACL-induced hemolysis and K/sup +/ efflux were dependent upon the pH of the external media. CHLO ALC-induced K/sup +/ efflux and hemolysis showed a slight pH dependence, with increased potency of the compound detected over the pH range 8.3-9.4 CHLO ALC-induced protection against hypotonic hemolysis was pH independent. The potency of CHLO in all three assays decreased as the pH was raised from 6.4 to 9.4. (/sup 14/C)-CHLO and (/sup 14/C)-CHLO ALC binding to OE and OE membranes was pH independent. However, the binding of (/sup 14/C)-CHLO to polypropylene and glass was pH dependent. (/sup 14/C)-CHLO binding to polypropylene and glass decreased from pH 6.4 to pH 10.4. The pKa of CHLO was estimated to be 8.9. After the CHLO results were corrected for the fraction of CHLO present in the unionized form, it was estimated the ionized CHLO possessed 1/3 to 1/20 of the activity of the unionized species.

  8. Long-term consequences of neonatal exposure to chlordecone.

    PubMed

    Sierra, V; Uphouse, L

    1986-01-01

    Neonate, female rats pups were injected with varying doses of chlordecone in cotton seed oil or with 1 mg chlordecone in dimethylsulfoxide. The effects of these neonatal treatments on vaginal opening, persistent vaginal estrus and adult sexual behavior were examined. Females treated with chlordecone showed earlier onset of vaginal opening and developed persistent vaginal estrus in adulthood. Sexual behavior of intact adult females was irregular but after ovariectomy and estrogen plus progesterone hormonal priming, chlordecone treated females showed normal lordosis responding. Females did not appear to have been defeminized by the neonatal chlordecone. After treatment with testosterone in adulthood, chlordecone treated females exhibited high levels of mounting behavior indicating that the neonatal treatments may have masculinized the developing hypothalamus. No significant effects of the vehicle were detected.

  9. Soil microstructure and organic matter: keys for chlordecone sequestration.

    PubMed

    Woignier, T; Fernandes, P; Soler, A; Clostre, F; Carles, C; Rangon, L; Lesueur-Jannoyer, M

    2013-11-15

    Past applications of chlordecone, a persistent organochlorine pesticide, have resulted in diffuse pollution of agricultural soils, and these have become sources of contamination of cultivated crops as well as terrestrial and marine ecosystems. Chlordecone is a very stable and recalcitrant molecule, mainly present in the solid phase, and has a strong affinity for organic matter. To prevent consumer and ecosystem exposure, factors that influence chlordecone migration in the environment need to be evaluated. In this study, we measured the impact of incorporating compost on chlordecone sequestration in andosols as a possible way to reduce plant contamination. We first characterized the transfer of chlordecone from soil to plants (radish, cucumber, and lettuce). Two months after incorporation of the compost, soil-plant transfers were reduced by a factor of 1.9-15 depending on the crop. Our results showed that adding compost modified the fractal microstructure of allophane clays thus favoring chlordecone retention in andosols. The complex structure of allophane and the associated low accessibility are important characteristics governing the fate of chlordecone. These results support our proposal for an alternative strategy that is quite the opposite of total soil decontamination: chlordecone sequestration.

  10. Soil microstructure and organic matter: keys for chlordecone sequestration.

    PubMed

    Woignier, T; Fernandes, P; Soler, A; Clostre, F; Carles, C; Rangon, L; Lesueur-Jannoyer, M

    2013-11-15

    Past applications of chlordecone, a persistent organochlorine pesticide, have resulted in diffuse pollution of agricultural soils, and these have become sources of contamination of cultivated crops as well as terrestrial and marine ecosystems. Chlordecone is a very stable and recalcitrant molecule, mainly present in the solid phase, and has a strong affinity for organic matter. To prevent consumer and ecosystem exposure, factors that influence chlordecone migration in the environment need to be evaluated. In this study, we measured the impact of incorporating compost on chlordecone sequestration in andosols as a possible way to reduce plant contamination. We first characterized the transfer of chlordecone from soil to plants (radish, cucumber, and lettuce). Two months after incorporation of the compost, soil-plant transfers were reduced by a factor of 1.9-15 depending on the crop. Our results showed that adding compost modified the fractal microstructure of allophane clays thus favoring chlordecone retention in andosols. The complex structure of allophane and the associated low accessibility are important characteristics governing the fate of chlordecone. These results support our proposal for an alternative strategy that is quite the opposite of total soil decontamination: chlordecone sequestration. PMID:24056248

  11. Mechanistic study of chlordecone-induced endocrine disruption: Based on an adverse outcome pathway network.

    PubMed

    Yang, Lihua; Zhou, Bingsheng; Zha, Jinmiao; Wang, Zijian

    2016-10-01

    The adverse outcome pathway (AOP) framework could be helpful for chemical risk assessment and mechanistic research. The aim of the present study was to unravel the mechanism of chlordecone-induced endocrine disruption by illustrating the main molecular initiating event (MIE)/perturbations responsible for the observed effects. In silico simulations were performed to predict the MIE(s), and the results pointed to agonistic interaction with estrogen receptors (ERα, ERβ), androgen receptor (AR), cytochrome P450 (CYP19A) by chlordecone. In vivo endocrine disruptions were evaluated in rare minnow (Gobiocypris rarus) exposed to 0.01, 0.1, 1 and 10 μg L(-1) chlordecone from 2 h post-fertilization until sexually mature. In the females, increases of vitellogenin (vtg) mRNA levels in liver and gonad, plasma estradiol (E2), testosterone (T) and E2/T, and renalsomatic index confirmed the role of agonism of ER and CYP19A as MIEs, but the decreased gonadosomatic index, degenerated ovaries as well as the feed-forward response pointed to other potential but important MIEs and corresponding AOPs. In the males, increased E2/T ratio, increased testis vtg mRNA levels and occurrence of intersex confirmed the roles of agonism of ERα and CYP19A as main MIEs in chlordecone-induced endocrine disruptions. Our results also fetches out the limit of AOPs in predicting the adverse outcomes and explaining the mechanism of chemicals at present, thus reflected a critical need for expanding AOPs and AOP network before using it in chemical risk assessment. PMID:27448318

  12. Effect of home food processing on chlordecone (organochlorine) content in vegetables.

    PubMed

    Clostre, Florence; Letourmy, Philippe; Thuriès, Laurent; Lesueur-Jannoyer, Magalie

    2014-08-15

    Decades after their use and their ban, organochlorine pesticides still pollute soil, water and food and lead to human and ecosystem exposure. In the case of chlordecone, human exposure is mainly due to the consumption of polluted food. We studied the effect of preparation and cooking in five vegetable products, three root vegetables (yam, dasheen and sweet potato) and two cucurbits (cucumber and pumpkin), among the main contributors to exposure to chlordecone in food in the French West Indies. Boiling the vegetables in water had no effect on chlordecone content of the vegetables and consequently on consumer exposure. The peel was three to 40-fold more contaminated than the pulp except cucumber, where the difference was less contrasted. The edible part is thus significantly less contaminated and peeling is recommended after rinsing to reduce consumer exposure, particularly for food grown in home gardens with contaminated soils. The type of soil had no consistent effect on CLD distribution but plot did. Peel and pulp composition (lipids and fibers) appear to partially account for CLD distribution in the product. PMID:24914532

  13. Chlordecone retention in the fractal structure of volcanic clay.

    PubMed

    Woignier, Thierry; Clostre, Florence; Macarie, Hervé; Jannoyer, Magalie

    2012-11-30

    Chlordecone (CHLD), a soil and foodstuff pollutant, as well as an environmentally persistent organochlorine insecticide, was used intensively in banana fields. The chlordecone uptake of three crops was measured for two types of polluted soils: allophanic and non-allophanic. The uptake is lower for allophanic soils even if their chlordecone content is higher than with non-allophanic soils. The fractal structure of the allophane aggregates was characterized at the nanoscale by small angle X-rays scattering, pore size distribution and transmission electron microscopy. We showed that clay microstructures should be an important physico-chemical factor governing the fate of chlordecone in the environment. Allophanic clays result in two counterintuitive findings: higher contaminant trappings yet lower contaminant availability. We propose that this specific, tortuous structure, along with its associated low accessibility, partly explains the low availability of chlordecone confined in allophanic soils. Capsule The fractal and tortuous microstructure of allophane clay favours the chlordecone retention in soils and disfavours the crop uptake. PMID:23062511

  14. Chlordecone impaired biliary excretion: In vivo and in vitro correlates

    SciTech Connect

    Rochelle, L.G.

    1989-01-01

    The focus of this research was to investigate mechanisms of impaired biliary excretion localized to the bile canaliculus. Two modes of chlordecone (CD) action were investigated: (1) direct effects on organic anion transport at the bile canaliculus; and/or (2) general membrane perturbation, indirectly affecting anion transport proteins. Bile canaliculi-enriched fractions (BCEF) were isolated from rat livers in order to characterize effects of CD on this domain of the plasma membranes. CD inhibited the initial rate leading to a peak Na{sup +}-stimulated ({sup 3}H)L-glutamate uptake in BCEF CD inhibition of the initial or Na{sup +}-gradient driven phase of ({sup 3}H)L-glutamate uptake suggested that CD was affecting maintenance of the Na{sup +}-gradient by the BCEF membrane vesicles. In vivo PG anion excretion was inhibited as well as in vitro ({sup 3}H)L-glutamate transport at 24 hr following in vivo CD treatment of rats. Seventy-two hr following CD treatment, rats recovered to control PG excretion levels. PG excretory performance was regained in 72 hr pretreated rats despite an increase in liver CD concentration. Liver CD concentrations in 24 hr pretreated rats were approximately 50% of the concentrations in 72 hr pretreated rats. At low CD concentrations, there was no evidence of general membrane perturbation in terms of immobilization of the lipid electron spin resonance probe, 16-doxyl stearate, in BCEF. Mobility of 16-doxyl stearate in BCEF was reduced at in vitro CD concentrations of 0.20 {mu}mol/mg protein or greater. CD did reduce hepatobiliary permeability to ({sup 14}C)mannitol in 24 and 72 hr pretreated rats; perhaps restricting movement through membrane aqueous pores.

  15. Chlordecone Transfer and Distribution in Maize Shoots.

    PubMed

    Pascal-Lorber, Sophie; Létondor, Clarisse; Liber, Yohan; Jamin, Emilien L; Laurent, François

    2016-01-20

    Chlordecone (CLD) is a persistent organic pollutant (POP) that was mainly used as an insecticide against banana weevils in the French West Indies (1972-1993). Transfer of CLD via the food chain is now the major mechanism for exposure of the population to CLD. The uptake and the transfer of CLD were investigated in shoots of maize, a C4 model plant growing under tropical climates, to estimate the exposure of livestock via feed. Maize plants were grown on soils contaminated with [(14)C]CLD under controlled conditions. The greatest part of the radioactivity was associated with roots, nearly 95%, but CLD was detected in whole shoots, concentrations in old leaves being higher than those in young ones. CLD was thus transferred from the base toward the plant top, forming an acropetal gradient of contaminant. In contrast, results evidenced the existence of a basipetal gradient of CLD concentration within leaves whose extremities accumulated larger amounts of CLD because of evapotranspiration localization. Extractable residues accounted for two-thirds of total residues both in roots and in shoots. This study highlighted the fact that the distribution of CLD contamination within grasses resulted from a conjunction between the age and evapotranspiration rate of tissues. CLD accumulation in fodder may be the main route of exposure for livestock. PMID:26701746

  16. Distinct bacterial community structure of 3 tropical volcanic soils from banana plantations contaminated with chlordecone in Guadeloupe (French West Indies).

    PubMed

    Mercier, Anne; Dictor, Marie-Christine; Harris-Hellal, Jennifer; Breeze, Dominique; Mouvet, Christophe

    2013-08-01

    In the French West Indies (FWI), the soil, andosols, ferralsols and nitisols, is highly polluted by chlordecone, although this organochlorine insecticide extensively applied to banana crops has been banned for 20years. This contamination has led to a major human health concern inducing the need for remediation of the contaminated soils. Work was conducted to help to evaluate the impact of remediation processes on the microbial communities from these soils. Microbial biomass was estimated after direct DNA extraction from three chlordecone-contaminated soils (an andosol, a ferralsol and a nitisol) and the bacterial community analyzed using t-RFLP. The FWI volcanic andosol was particularly recalcitrant to usual direct DNA extraction protocols hampering analysis of soil microbial communities until now, in contrast with the 2 other soils. For the first time, DNA was directly extracted from a FWI andosol based on yeast RNA addition at the lysis step. Differences in microbial biomass were thus observed between the 3 FWI soils. Moreover, the bacterial community structure was significantly distinct from each other's and related to soil physico-chemical characteristics. Interestingly, differences in bacterial diversity could not be exclusively attributed to the level of chlordecone contamination.

  17. Pentose pathway in human liver.

    PubMed Central

    Magnusson, I; Chandramouli, V; Schumann, W C; Kumaran, K; Wahren, J; Landau, B R

    1988-01-01

    [1-14C]Ribose and [2-14C]glucose were given to normal subjects along with glucose loads (1 g per kg of body weight) after administration of diflunisal and acetaminophen, drugs that are excreted in urine as glucuronides. Distributions of 14C were determined in the carbons of the excreted glucuronides and in the glucose from blood samples drawn from hepatic veins before and after glucagon administration. Eighty percent or more of the 14C from [1-14C]ribose incorporated into the glucuronic acid moiety of the glucuronides was in carbons 1 and 3, with less than 8% in carbon 2. In glucuronic acid from glucuronide excreted when [2-14C]glucose was given, 3.5-8.1% of the 14C was in carbon 1, 2.5-4.3% in carbon 3, and more than 70% in carbon 2. These distributions are in accord with the glucuronides sampling the glucose unit of the glucose 6-phosphate pool that is a component of the pentose pathway and is intermediate in glycogen formation. It is concluded that the glucuronic acid conjugates of the drugs can serve as a noninvasive means of sampling hepatic glucose 6-phosphate. In human liver, as in animal liver, the classical pentose pathway functions, not the L-type pathway, and only a small percentage of the glucose is metabolized via the pathway. PMID:3133657

  18. Pentose pathway in human liver

    SciTech Connect

    Magnusson, I.; Chandramouli, V.; Schumann, W.C.; Kumaran, K.; Wahren, J.; Landau, B.R. )

    1988-07-01

    (1-{sup 14}C)Ribose and (1-{sup 14}C)glucose were given to normal subjects along with glucose loads (1 g per kg of body weight) after administration of diflunisal and acetaminophen, drugs that are excreted in urine as glucuronides. Distributions of {sup 14}C were determined in the carbons of the excreted glucoronides and in the glucose from blood samples drawn from hepatic veins before and after glucagon administration. Eighty percent or more of the {sup 14}C from (1-{sup 14}C)ribose incorporated into the glucuronic acid moiety of the glucuronides was in carbons 1 and 3, with less than 8% in carbon 2. In glucuronic acid from glucuronide excreted when (2-{sup 14}C)glucose was given, 3.5-8.1% of the {sup 14}C was in carbon 1, 2.5-4.3% in carbon 3, and more than 70% in carbon 2. These distributions are in accord with the glucuronides sampling the glucose unit of the glucose 6-phosphate pool that is a component of the pentose pathway and is intermediate in glycogen formation. It is concluded that the glucuronic acid conjugates of the drugs can serve as a noninvasive means of sampling hepatic glucose 6-phosphate. In human liver, as in animal liver, the classical pentose pathway functions, not the L-type pathway, and only a small percentage of the glucose is metabolized via the pathway.

  19. Humanized mice with ectopic artificial liver tissues

    PubMed Central

    Chen, Alice A.; Thomas, David K.; Ong, Luvena L.; Schwartz, Robert E.; Golub, Todd R.; Bhatia, Sangeeta N.

    2011-01-01

    “Humanized” mice offer a window into aspects of human physiology that are otherwise inaccessible. The best available methods for liver humanization rely on cell transplantation into immunodeficient mice with liver injury but these methods have not gained widespread use due to the duration and variability of hepatocyte repopulation. In light of the significant progress that has been achieved in clinical cell transplantation through tissue engineering, we sought to develop a humanized mouse model based on the facile and ectopic implantation of a tissue-engineered human liver. These human ectopic artificial livers (HEALs) stabilize the function of cryopreserved primary human hepatocytes through juxtacrine and paracrine signals in polymeric scaffolds. In contrast to current methods, HEALs can be efficiently established in immunocompetent mice with normal liver function. Mice transplanted with HEALs exhibit humanized liver functions persistent for weeks, including synthesis of human proteins, human drug metabolism, drug–drug interaction, and drug-induced liver injury. Here, mice with HEALs are used to predict the disproportionate metabolism and toxicity of “major” human metabolites using multiple routes of administration and monitoring. These advances may enable manufacturing of reproducible in vivo models for diverse drug development and research applications. PMID:21746904

  20. Detection and quantification of chlordecone in contaminated soils from the French West Indies by GC-MS using the 13C10-chlordecone stable isotope as a tracer.

    PubMed

    Martin-Laurent, Fabrice; Sahnoun, Mehdi M; Merlin, Chloé; Vollmer, Guy; Lübke, Markus

    2014-04-01

    Chlordecone is an organochlorine insecticide that has been widely used to control banana weevil in the French West Indies. As a result of this intense use, up to 20,000 ha are contaminated by this insecticide in the French West Indies, and this causes environmental damage and health problems. A scenario of exposure was drawn by French authorities, based on land usage records. Many efforts have been made to monitor the occurrence of chlordecone and its main metabolites using different analytical methods, including GC, GC/MS, LC/MS, and NIRS. Although these different methods allow for the detection and quantification of chlordecone from soils, none of them estimate the bottleneck caused by extraction of this organochlorine from soils with high adsorption ability. In this study, we used (13)C10-chlordecone as a tracer to estimate chlordecone extraction yield and to quantify chlordecone in soil extracts based on the (13)C/(12)C isotope dilution. We report the optimization of (13)C10-chlordecone extraction from an Andosol. The method was found to be linear from 0.118 to 43 mg kg(-1) in the Andosol, with an instrumental detection limit estimated at 8.84 μg kg(-1). This method showed that chlordecone ranged from 35.4 down to 0.18 mg kg(-1) in Andosol, Nitisol, Ferralsol, and Fluvisol soil types. Traces of the metabolite β-monohydrochlordecone were detected in the Andosol, Nitisol, and Ferralsol soil samples. This last result indicates that this method could be useful to monitor the fate of chlordecone in soils of the French West Indies. PMID:23733305

  1. Compost addition reduces porosity and chlordecone transfer in soil microstructure.

    PubMed

    Woignier, Thierry; Clostre, Florence; Fernandes, Paula; Rangon, Luc; Soler, Alain; Lesueur-Jannoyer, Magalie

    2016-01-01

    Chlordecone, an organochlorine insecticide, pollutes soils and contaminates crops and water resources and is biomagnified by food chains. As chlordecone is partly trapped in the soil, one possible alternative to decontamination may be to increase its containment in the soil, thereby reducing its diffusion into the environment. Containing the pesticide in the soil could be achieved by adding compost because the pollutant has an affinity for organic matter. We hypothesized that adding compost would also change soil porosity, as well as transport and containment of the pesticide. We measured the pore features and studied the nanoscale structure to assess the effect of adding compost on soil microstructure. We simulated changes in the transport properties (hydraulic conductivity and diffusion) associated with changes in porosity. During compost incubation, the clay microstructure collapsed due to capillary stresses. Simulated data showed that the hydraulic conductivity and diffusion coefficient were reduced by 95 and 70% in the clay microstructure, respectively. Reduced transport properties affected pesticide mobility and thus helped reduce its transfer from the soil to water and to the crop. We propose that the containment effect is due not only to the high affinity of chlordecone for soil organic matter but also to a trapping mechanism in the soil porosity.

  2. Compost addition reduces porosity and chlordecone transfer in soil microstructure.

    PubMed

    Woignier, Thierry; Clostre, Florence; Fernandes, Paula; Rangon, Luc; Soler, Alain; Lesueur-Jannoyer, Magalie

    2016-01-01

    Chlordecone, an organochlorine insecticide, pollutes soils and contaminates crops and water resources and is biomagnified by food chains. As chlordecone is partly trapped in the soil, one possible alternative to decontamination may be to increase its containment in the soil, thereby reducing its diffusion into the environment. Containing the pesticide in the soil could be achieved by adding compost because the pollutant has an affinity for organic matter. We hypothesized that adding compost would also change soil porosity, as well as transport and containment of the pesticide. We measured the pore features and studied the nanoscale structure to assess the effect of adding compost on soil microstructure. We simulated changes in the transport properties (hydraulic conductivity and diffusion) associated with changes in porosity. During compost incubation, the clay microstructure collapsed due to capillary stresses. Simulated data showed that the hydraulic conductivity and diffusion coefficient were reduced by 95 and 70% in the clay microstructure, respectively. Reduced transport properties affected pesticide mobility and thus helped reduce its transfer from the soil to water and to the crop. We propose that the containment effect is due not only to the high affinity of chlordecone for soil organic matter but also to a trapping mechanism in the soil porosity. PMID:26250815

  3. Adrenergic receptors in human fetal liver membranes.

    PubMed

    Falkay, G; Kovács, L

    1990-01-01

    The adrenergic receptor binding capacities in human fetal and adult livers were measured to investigate the mechanism of the reduced alpha-1 adrenoreceptor response of the liver associated with a reciprocal increase in beta-adrenoreceptor activity in a number of conditions. Alpha-1 and beta-adrenoreceptor density were determined using 3H-prazosin and 3H-dihydroalprenolol, respectively, as radioligand. Heterogenous populations of beta-adrenoreceptors were found in fetal liver contrast to adult. Decreased alpha-1 and increased beta-receptor density were found which may relate to a decreased level in cellular differentiation. These findings may be important for the investigation of perinatal hypoglycaemia of newborns after treatment of premature labour with beta-mimetics. This is the first demonstration of differences in the ratio of alpha-1 and beta-adrenoceptors in human fetal liver.

  4. Obesity accelerates epigenetic aging of human liver.

    PubMed

    Horvath, Steve; Erhart, Wiebke; Brosch, Mario; Ammerpohl, Ole; von Schönfels, Witigo; Ahrens, Markus; Heits, Nils; Bell, Jordana T; Tsai, Pei-Chien; Spector, Tim D; Deloukas, Panos; Siebert, Reiner; Sipos, Bence; Becker, Thomas; Röcken, Christoph; Schafmayer, Clemens; Hampe, Jochen

    2014-10-28

    Because of the dearth of biomarkers of aging, it has been difficult to test the hypothesis that obesity increases tissue age. Here we use a novel epigenetic biomarker of aging (referred to as an "epigenetic clock") to study the relationship between high body mass index (BMI) and the DNA methylation ages of human blood, liver, muscle, and adipose tissue. A significant correlation between BMI and epigenetic age acceleration could only be observed for liver (r = 0.42, P = 6.8 × 10(-4) in dataset 1 and r = 0.42, P = 1.2 × 10(-4) in dataset 2). On average, epigenetic age increased by 3.3 y for each 10 BMI units. The detected age acceleration in liver is not associated with the Nonalcoholic Fatty Liver Disease Activity Score or any of its component traits after adjustment for BMI. The 279 genes that are underexpressed in older liver samples are highly enriched (1.2 × 10(-9)) with nuclear mitochondrial genes that play a role in oxidative phosphorylation and electron transport. The epigenetic age acceleration, which is not reversible in the short term after rapid weight loss induced by bariatric surgery, may play a role in liver-related comorbidities of obesity, such as insulin resistance and liver cancer. PMID:25313081

  5. Human Ex-Vivo Liver Model for Acetaminophen-induced Liver Damage.

    PubMed

    Schreiter, Thomas; Sowa, Jan-Peter; Schlattjan, Martin; Treckmann, Jürgen; Paul, Andreas; Strucksberg, Karl-Heinz; Baba, Hideo A; Odenthal, Margarete; Gieseler, Robert K; Gerken, Guido; Arteel, Gavin E; Canbay, Ali

    2016-01-01

    Reliable test systems to identify hepatotoxicity are essential to predict unexpected drug-related liver injury. Here we present a human ex-vivo liver model to investigate acetaminophen-induced liver injury. Human liver tissue was perfused over a 30 hour period with hourly sampling from the perfusate for measurement of general metabolism and clinical parameters. Liver function was assessed by clearance of indocyanine green (ICG) at 4, 20 and 28 hours. Six pieces of untreated human liver specimen maintained stable liver function over the entire perfusion period. Three liver sections incubated with low-dose acetaminophen revealed strong damage, with ICG half-lives significantly higher than in non-treated livers. In addition, the release of microRNA-122 was significantly higher in acetaminophen-treated than in non-treated livers. Thus, this model allows for investigation of hepatotoxicity in human liver tissue upon applying drug concentrations relevant in patients. PMID:27550092

  6. Human Ex-Vivo Liver Model for Acetaminophen-induced Liver Damage

    PubMed Central

    Schreiter, Thomas; Sowa, Jan-Peter; Schlattjan, Martin; Treckmann, Jürgen; Paul, Andreas; Strucksberg, Karl-Heinz; Baba, Hideo A.; Odenthal, Margarete; Gieseler, Robert K.; Gerken, Guido; Arteel, Gavin E.; Canbay, Ali

    2016-01-01

    Reliable test systems to identify hepatotoxicity are essential to predict unexpected drug-related liver injury. Here we present a human ex-vivo liver model to investigate acetaminophen-induced liver injury. Human liver tissue was perfused over a 30 hour period with hourly sampling from the perfusate for measurement of general metabolism and clinical parameters. Liver function was assessed by clearance of indocyanine green (ICG) at 4, 20 and 28 hours. Six pieces of untreated human liver specimen maintained stable liver function over the entire perfusion period. Three liver sections incubated with low-dose acetaminophen revealed strong damage, with ICG half-lives significantly higher than in non-treated livers. In addition, the release of microRNA-122 was significantly higher in acetaminophen-treated than in non-treated livers. Thus, this model allows for investigation of hepatotoxicity in human liver tissue upon applying drug concentrations relevant in patients. PMID:27550092

  7. Stem cell differentiation and human liver disease

    PubMed Central

    Zhou, Wen-Li; Medine, Claire N; Zhu, Liang; Hay, David C

    2012-01-01

    Human stem cells are scalable cell populations capable of cellular differentiation. This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells. Such an approach has the potential to improve our understanding of human biology and treating disease. In the future it may be possible to deploy novel stem cell-based approaches to treat human liver diseases. In recent years, efficient hepatic differentiation from human stem cells has been achieved by several research groups including our own. In this review we provide an overview of the field and discuss the future potential and limitations of stem cell technology. PMID:22563188

  8. Chlordecone, a mixed pregnane X receptor (PXR) and estrogen receptor alpha (ER{alpha}) agonist, alters cholesterol homeostasis and lipoprotein metabolism in C57BL/6 mice

    SciTech Connect

    Lee, Junga; Scheri, Richard C.; Zhang Yuan; Curtis, Lawrence R.

    2008-12-01

    Chlordecone (CD) is one of many banned organochlorine (OC) insecticides that are widespread persistent organic pollutants. OC insecticides alter lipid homeostasis in rodents at doses that are not neurotoxic or carcinogenic. Pretreatment of mice or rats with CD altered tissue distribution of a subsequent dose of [{sup 14}C]CD or [{sup 14}C]cholesterol (CH). Nuclear receptors regulate expression of genes important in the homeostasis of CH and other lipids. In this study, we report that CD suppresses in vitro reporter systems for human liver X receptors (LXRs) and activates those for human farnesoid X receptor (FXR), pregnane X receptor (PXR) and estrogen receptor {alpha} (ER{alpha}) in a concentration-dependent manner (0-50 {mu}M). Consistent with human PXR activation in vitro, three days after a single dose of CD (15 mg/kg) hepatic microsomal CYP3A11 protein increases in C57BL/6 mice. CD decreases hepatic CH ester content without altering total CH concentration. Apolipoprotein A-I (apoA-I) contents of hepatic lipoprotein-rich and microsomal fractions of CD-treated mice are higher than controls. There is a significant reduction in non-high density lipoprotein CH but not apolipoprotein B-48/100 (apoB-48/100) in plasma from CD-treated mice after a 4 h fast. At 14 days after 15 mg CD/kg apoA-I and apoB-100 proteins but not CYP3A11 protein in hepatic microsomes are similar to controls. This work indicates that altered CH homeostasis is a mode of OC insecticide action of relevance after a single dose. This at least partially explains altered CH tissue distribution in CD-pretreated mice.

  9. Native fluorescence characterization of human liver abnormalities

    NASA Astrophysics Data System (ADS)

    Ganesan, Singaravelu; Madhuri, S.; Aruna, Prakasa R.; Suchitra, S.; Srinivasan, T. G.

    1999-05-01

    Fluorescence spectroscopy of intrinsic biomolecules has been extensively used in biology and medicine for the past several decades. In the present study, we report the native fluorescence characteristics of blood plasma from normal human subjects and patients with different liver abnormalities such as hepatitis, leptospirosis, jaundice, cirrhosis and liver cell failure. Native fluorescence spectra of blood plasma -- acetone extract were measured at 405 nm excitation. The average spectrum of normal blood plasma has a prominent emission peak around 464 nm whereas in the case of liver diseased subjects, the primary peak is red shifted with respect to normal. In addition, liver diseased cases show distinct secondary emission peak around 615 nm, which may be attributed to the presence of endogenous porphyrins. The red shift of the prominent emission peak with respect to normal is found to be maximum for hepatitis and minimum for cirrhosis whereas the secondary emission peak around 615 nm was found to be more prominent in the case of cirrhosis than the rest. The ratio parameter I465/I615 is found to be statistically significant (p less than 0.001) in discriminating liver abnormalities from normal.

  10. Molecular Structure of Human-Liver Glycogen

    PubMed Central

    Deng, Bin; Sullivan, Mitchell A.; Chen, Cheng; Li, Jialun; Powell, Prudence O.; Hu, Zhenxia; Gilbert, Robert G.

    2016-01-01

    Glycogen is a highly branched glucose polymer which is involved in maintaining blood-sugar homeostasis. Liver glycogen contains large composite α particles made up of linked β particles. Previous studies have shown that the binding which links β particles into α particles is impaired in diabetic mice. The present study reports the first molecular structural characterization of human-liver glycogen from non-diabetic patients, using transmission electron microscopy for morphology and size-exclusion chromatography for the molecular size distribution; the latter is also studied as a function of time during acid hydrolysis in vitro, which is sensitive to certain structural features, particularly glycosidic vs. proteinaceous linkages. The results are compared with those seen in mice and pigs. The molecular structural change during acid hydrolysis is similar in each case, and indicates that the linkage of β into α particles is not glycosidic. This result, and the similar morphology in each case, together imply that human liver glycogen has similar molecular structure to those of mice and pigs. This knowledge will be useful for future diabetes drug targets. PMID:26934359

  11. Contamination of free-range ducks by chlordecone in Martinique (French West Indies): a field study.

    PubMed

    Jondreville, Catherine; Lavigne, Anaïs; Jurjanz, Stefan; Dalibard, Christophe; Liabeuf, Jean-Marie; Clostre, Florence; Lesueur-Jannoyer, Magalie

    2014-09-15

    The former use of chlordecone (CLD) in the French West Indies has resulted in long-term pollution of soils and subsequently of food chains. In contaminated areas, free-range ducks used to control weeds in orchards may be exposed to CLD through polluted soil ingestion. The question arises whether they may be consumed. Muscovy ducks were raised on a guava orchard planted on a soil moderately contaminated (410 μg CLD/kg dry matter). Ducks were raised indoor up to 6 weeks of age and allowed to range freely outdoors thereafter. Twenty-nine females were sequentially slaughtered by groups of 2 to 5 ducks, after 4, 16, 19, 22 or 26 weeks spent in the orchard or after 16-17 weeks in the orchard followed by 3, 6 or 9 weeks in a closed shelter for depuration. CLD concentration increased from 258 to 1051, 96 to 278, 60 to 169 and 48 to 145 μg/kg fresh matter (FM) as the exposure through grazing increased from 4 to 22 weeks, in liver, abdominal fat and leg with and without skin, respectively. Eggs collected in the orchard contained up to 1001 μg CLD/kg FM. All these values exceeded the Maximum Residue Limit (MRL) of 20 μg/kg FM. CLD concentration in all tissues was divided by around 10 within the 9-week confinement period. Despite this quite rapid decontamination, it is estimated that 12-13 weeks would be required to achieve the MRL in liver and in eggs, and 5-6 weeks in leg muscle. Such durations would be too long in practice. Thus, the consumption of products from free-range ducks should be avoided, even in areas mildly contaminated with CLD.

  12. Uptake and distribution of chlordecone in radish: different contamination routes in edible roots.

    PubMed

    Létondor, Clarisse; Pascal-Lorber, Sophie; Laurent, François

    2015-01-01

    Chlordecone (CLD) was an organochlorine insecticide mainly used to struggle against banana weevils in the French West Indies. Forbidden since 1993, it has been a long-term contaminant of soils and aquatic environments. Crops growing in contaminated soils lead to human exposure by food consumption. We used radiolabeled [(14)C]-CLD to investigate the contamination ways into radish, a model of edible roots. Radish plants were able to accumulate CLD in both roots (RCF35d 647) and tubers (edible parts, CF35d 6.3). CLD was also translocated to leaves (CF35d 1.7). The contamination of tuber was mainly due to peridermic adsorption or CLD systemic translocation to the pith. TSCF was 3.44×10(-)(3). CLD diffused across periderm to internal tissues. We calculated a mean flux of diffusion J through periderm about 5.71×10(-)(14)gcm(-)(2)s(-)(1). We highlighted different contamination routes of the tuber, (i) adsorption on periderm followed by diffusion of CLD towards underlying tissues, cortex, xylem, and pith (ii) adsorption by roots and translocation by the transpiration stream followed by diffusion from xylem vessels towards inner tissues, pith, and peripheral tissues, cortex and periderm. Concerning chemical risk assessment for other tubers, contamination would depend on various parameters, the thickness of periderm and CLD periderm permeance, the origin of secondary tissues - from cortex and/or pith - , the importance of xylem flow in tuber, and the lipid amount within tuber. PMID:25433399

  13. Uptake and distribution of chlordecone in radish: different contamination routes in edible roots.

    PubMed

    Létondor, Clarisse; Pascal-Lorber, Sophie; Laurent, François

    2015-01-01

    Chlordecone (CLD) was an organochlorine insecticide mainly used to struggle against banana weevils in the French West Indies. Forbidden since 1993, it has been a long-term contaminant of soils and aquatic environments. Crops growing in contaminated soils lead to human exposure by food consumption. We used radiolabeled [(14)C]-CLD to investigate the contamination ways into radish, a model of edible roots. Radish plants were able to accumulate CLD in both roots (RCF35d 647) and tubers (edible parts, CF35d 6.3). CLD was also translocated to leaves (CF35d 1.7). The contamination of tuber was mainly due to peridermic adsorption or CLD systemic translocation to the pith. TSCF was 3.44×10(-)(3). CLD diffused across periderm to internal tissues. We calculated a mean flux of diffusion J through periderm about 5.71×10(-)(14)gcm(-)(2)s(-)(1). We highlighted different contamination routes of the tuber, (i) adsorption on periderm followed by diffusion of CLD towards underlying tissues, cortex, xylem, and pith (ii) adsorption by roots and translocation by the transpiration stream followed by diffusion from xylem vessels towards inner tissues, pith, and peripheral tissues, cortex and periderm. Concerning chemical risk assessment for other tubers, contamination would depend on various parameters, the thickness of periderm and CLD periderm permeance, the origin of secondary tissues - from cortex and/or pith - , the importance of xylem flow in tuber, and the lipid amount within tuber.

  14. Expression of biotransformation and oxidative stress genes in the giant freshwater prawn Macrobrachium rosenbergii exposed to chlordecone.

    PubMed

    Gaume, Béatrice; Dodet, Nathalie; Thomé, Jean-Pierre; Lemoine, Soazig

    2015-06-01

    Chlordecone is a persistent organochlorine pesticide widely used between 1972 and 1993 in the French West Indies to control the root borer in banana fields. Chlordecone use resulted in long-term pollution of soils, contamination of waters, of aquatic organisms, and of fields. Chlordecone is known to be neurotoxic, to increase prostate cancer, and to have negative effects on cognitive and motor development during infancy. In Guadeloupe, most of the freshwater species living in contaminated rivers exceed the French legal limit of 20 μg·kg(-1) wet weight. In the present study, we chose a transcriptomic approach to study the cellular effects of chlordecone in the giant freshwater prawn Macrobrachium rosenbergii, an important economical species in Guadeloupe. Quantitative PCR revealed an induction of genes involved in defense mechanism against oxidative stress (catalase and selenium-dependent glutathione peroxidase) in prawns exposed to low environmental concentrations of chlordecone after 12 and 24 h of exposure. In prawns reared in a contaminated farm, transcription of genes involved in the biotransformation process (cytochrome P450 and glutathione-S-transferase (GST)) were induced after 8 days of exposure. Our results provide information on the mechanims of defense induced by chlordecone in aquatic crustacean species. This gene expression study of selected genes should be further strengthened by proteomic analyses and enzymatic activity assays to confirm the response of these biomarkers of stress in crustaceans and to give new insights into the mechanism of toxicity by chlordecone.

  15. Extracellular Matrix Molecular Remodeling in Human Liver Fibrosis Evolution

    PubMed Central

    Baiocchini, Andrea; Montaldo, Claudia; Conigliaro, Alice; Grimaldi, Alessio; Correani, Virginia; Mura, Francesco; Ciccosanti, Fabiola; Rotiroti, Nicolina; Brenna, Alessia; Montalbano, Marzia; D’Offizi, Gianpiero; Capobianchi, Maria Rosaria; Alessandro, Riccardo; Piacentini, Mauro; Schininà, Maria Eugenia; Maras, Bruno; Del Nonno, Franca; Tripodi, Marco; Mancone, Carmine

    2016-01-01

    Chronic liver damage leads to pathological accumulation of ECM proteins (liver fibrosis). Comprehensive characterization of the human ECM molecular composition is essential for gaining insights into the mechanisms of liver disease. To date, studies of ECM remodeling in human liver diseases have been hampered by the unavailability of purified ECM. Here, we developed a decellularization method to purify ECM scaffolds from human liver tissues. Histological and electron microscopy analyses demonstrated that the ECM scaffolds, devoid of plasma and cellular components, preserved the three-dimensional ECM structure and zonal distribution of ECM components. This method has been then applied on 57 liver biopsies of HCV-infected patients at different stages of liver fibrosis according to METAVIR classification. Label-free nLC-MS/MS proteomics and computation biology were performed to analyze the ECM molecular composition in liver fibrosis progression, thus unveiling protein expression signatures specific for the HCV-related liver fibrotic stages. In particular, the ECM molecular composition of liver fibrosis was found to involve dynamic changes in matrix stiffness, flexibility and density related to the dysregulation of predominant collagen, elastic fibers and minor components with both structural and signaling properties. This study contributes to the understanding of the molecular bases underlying ECM remodeling in liver fibrosis and suggests new molecular targets for fibrolytic strategies. PMID:26998606

  16. Mouse models of liver fibrosis mimic human liver fibrosis of different etiologies

    PubMed Central

    Martínez, Allyson K.; Maroni, Luca; Marzioni, Marco; Ahmed, Syed T.; Milad, Mena; Ray, Debolina; Alpini, Gianfranco; Glaser, Shannon S.

    2014-01-01

    The liver has the amazing capacity to repair itself after injury; however, the same processes that are involved in liver regeneration after acute injury can cause serious consequences during chronic liver injury. In an effort to repair damage, activated hepatic stellate cells trigger a cascade of events that lead to deposition and accumulation of extracellular matrix components causing the progressive replacement of the liver parenchyma by scar tissue, thus resulting in fibrosis. Although fibrosis occurs as a result of many chronic liver diseases, the molecular mechanisms involved depend on the underlying etiology. Since studying liver fibrosis in human subjects is complicated by many factors, mouse models of liver fibrosis that mimic the human conditions fill this void. This review summarizes the general mouse models of liver fibrosis and mouse models that mimic specific human disease conditions that result in liver fibrosis. Additionally, recent progress that has been made in understanding the molecular mechanisms involved in the fibrogenic processes of each of the human disease conditions is highlighted. PMID:25396098

  17. Plasmodium vivax liver stage development and hypnozoite persistence in human liver-chimeric mice.

    PubMed

    Mikolajczak, Sebastian A; Vaughan, Ashley M; Kangwanrangsan, Niwat; Roobsoong, Wanlapa; Fishbaugher, Matthew; Yimamnuaychok, Narathatai; Rezakhani, Nastaran; Lakshmanan, Viswanathan; Singh, Naresh; Kaushansky, Alexis; Camargo, Nelly; Baldwin, Michael; Lindner, Scott E; Adams, John H; Sattabongkot, Jetsumon; Prachumsri, Jetsumon; Kappe, Stefan H I

    2015-04-01

    Plasmodium vivax malaria is characterized by periodic relapses of symptomatic blood stage parasite infections likely initiated by activation of dormant liver stage parasites-hypnozoites. The lack of tractable P. vivax animal models constitutes an obstacle in examining P. vivax liver stage infection and drug efficacy. To overcome this obstacle, we have used human liver-chimeric (huHep) FRG KO mice as a model for P. vivax infection. FRG KO huHep mice support P. vivax sporozoite infection, liver stage development, and hypnozoite formation. We show complete P. vivax liver stage development, including maturation into infectious exo-erythrocytic merozoites as well as the formation and persistence of hypnozoites. Prophylaxis or treatment with the antimalarial primaquine can prevent and eliminate liver stage infection, respectively. Thus, P. vivax-infected FRG KO huHep mice are a model to investigate liver stage development and dormancy and may facilitate the discovery of drugs targeting relapsing malaria.

  18. Relative bioavailability of soil-bound chlordecone in growing lambs.

    PubMed

    Jurjanz, S; Jondreville, C; Mahieu, M; Fournier, A; Archimède, H; Rychen, G; Feidt, C

    2014-10-01

    The pollution of soil with the pesticide chlordecone (CLD) is a problem for the use of agricultural surfaces even years after its use has been forbidden. Therefore, the exposure of free-ranged animals such as ruminants needs to be investigated in order to assess the risk of contamination of the food chain. Indeed, measured concentrations could be integrated in a lowered extent if the soil binding would reduce the bioavailability of the pesticide. This bioavailability of soil-bound CLD in a heavily polluted andosol has been investigated relatively of CLD given via spiked oil. Twenty-four weaned lambs were exposed to graded doses of 2, 4 or 6 μg CLD/kg body weight during 15 days via the contaminated soil in comparison to spiked oil. The concentration of this pesticide has been determined in two target tissues: blood serum and kidney fat. The relative bioavailability (RBA) corresponds to the slope ratio between the test matrix-contaminated soil- in comparison to the reference matrix oil. The RBA of the soil-bound CLD was not found to significantly differ from the reference matrix oil in lambs meaning that the pesticide ingested by grazing ruminants would not be sequestered by soil binding. Therefore, CLD from soil gets bioavailable within the intestinal level and exposure to contaminated soil has to be integrated in risk assessments.

  19. Evaluation of the ecotoxicological impact of the organochlorine chlordecone on soil microbial community structure, abundance, and function.

    PubMed

    Merlin, Chloé; Devers, Marion; Béguet, Jérémie; Boggio, Baptiste; Rouard, Nadine; Martin-Laurent, Fabrice

    2016-03-01

    The insecticide chlordecone applied for decades in banana plantations currently contaminates 20,000 ha of arable land in the French West Indies. Although the impact of various pesticides on soil microorganisms has been studied, chlordecone toxicity to the soil microbial community has never been assessed. We investigated in two different soils (sandy loam and silty loam) exposed to different concentrations of CLD (D0, control; D1 and D10, 1 and 10 times the agronomical dose) over different periods of time (3, 7, and 32 days): (i) the fate of chlordecone by measuring (14)C-chlordecone mass balance and (ii) the impact of chlordecone on microbial community structure, abundance, and function, using standardized methods (-A-RISA, taxon-specific quantitative PCR (qPCR), and (14)C-compounds mineralizing activity). Mineralization of (14)C-chlordecone was inferior below 1 % of initial (14)C-activity. Less than 2 % of (14)C-activity was retrieved from the water-soluble fraction, while most of it remained in the organic-solvent-extractable fraction (75 % of initial (14)C-activity). Only 23 % of the remaining (14)C-activity was measured in nonextractable fraction. The fate of chlordecone significantly differed between the two soils. The soluble and nonextractable fractions were significantly higher in sandy loam soil than in silty loam soil. All the measured microbiological parameters allowed discriminating statistically the two soils and showed a variation over time. The genetic structure of the bacterial community remained insensitive to chlordecone exposure in silty loam soil. In response to chlordecone exposure, the abundance of Gram-negative bacterial groups (β-, γ-Proteobacteria, Planctomycetes, and Bacteroidetes) was significantly modified only in sandy loam soil. The mineralization of (14)C-sodium acetate and (14)C-2,4-D was insensitive to chlordecone exposure in silty loam soil. However, mineralization of (14)C-sodium acetate was significantly reduced in soil

  20. Zebrafish Models of Human Liver Development and Disease

    PubMed Central

    Wilkins, Benjamin J.; Pack, Michael

    2016-01-01

    The liver performs a large number of essential synthetic and regulatory functions that are acquired during fetal development and persist throughout life. Their disruption underlies a diverse group of heritable and acquired diseases that affect both pediatric and adult patients. Although experimental analyses used to study liver development and disease are typically performed in cell culture models or rodents, the zebrafish is increasingly used to complement discoveries made in these systems. Forward and reverse genetic analyses over the past two decades have shown that the molecular program for liver development is largely conserved between zebrafish and mammals, and that the zebrafish can be used to model heritable human liver disorders. Recent work has demonstrated that zebrafish can also be used to study the mechanistic basis of acquired liver diseases. Here, we provide a comprehensive summary of how the zebrafish has contributed to our understanding of human liver development and disease. PMID:23897685

  1. Chimeric mice with a humanized liver as an animal model of troglitazone-induced liver injury.

    PubMed

    Kakuni, Masakazu; Morita, Mayu; Matsuo, Kentaro; Katoh, Yumiko; Nakajima, Miki; Tateno, Chise; Yokoi, Tsuyoshi

    2012-10-01

    Troglitazone (Tro) is a thiazolidinedione antidiabetic drug that was withdrawn from the market due to its association with idiosyncratic severe liver injury. Tro has never induced liver injury in experimental animals in vivo. It was assumed that the species differences between human and experimental animals in the pharmaco- or toxicokinetics of Tro might be associated with these observations. In this study, we investigated whether a chimeric mouse with a humanized liver that we previously established, whose replacement index with human hepatocytes is up to 92% can reproduce Tro-induced liver injury. When the chimeric mice were orally administered Tro for 14 or 23 days (1000mg/kg/day), serum alanine aminotransferase (ALT) was significantly increased by 2.1- and 3.6-fold, respectively. Co-administration of l-buthionine sulfoximine (10mM in drinking water), an inhibitor of glutathione (GSH) synthesis, unexpectedly prevented the Tro-dependent increase of ALT, which suggests that the GSH scavenging pathway will not be involved in Tro-induced liver injury. To elucidate the mechanism of the onset of liver injury, hepatic GSH content, the level of oxidative stress markers and phase I and phase II drug metabolizing enzymes were determined. However, these factors were not associated with Tro-induced liver injury. An immune-mediated reaction may be associated with Tro-induced liver toxicity in vivo, because the chimeric mouse is derived from an immunodeficient SCID mouse. In conclusion, we successfully reproduced Tro-induced liver injury using chimeric mice with a humanized liver, which provides a new animal model for studying idiosyncratic drug-induced liver injury.

  2. Assessment of the contamination of marine fauna by chlordecone in Guadeloupe and Martinique (Lesser Antilles).

    PubMed

    Dromard, Charlotte R; Bodiguel, Xavier; Lemoine, Soazig; Bouchon-Navaro, Yolande; Reynal, Lionel; Thouard, Emmanuel; Bouchon, Claude

    2016-01-01

    Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. From 2003 to 2013, seven campaigns of samplings have been conducted to evaluate the level of contamination of fish, crustaceans, and mollusks. The present study is the first assessment and the first comparison of the concentrations of chlordecone between marine areas, taxonomic groups, and ecological factors like trophic groups or preferential habitat of fish species. The four most contaminated marine areas are located downstream the contaminated rivers and banana plantations. Crustaceans seemed to be more sensitive to the contamination than fish or mollusks. Finally, when comparing contamination of fish according to their ecology, we found that fish usually living at the border of mangrove and presenting detritivores-omnivores diets were the most contaminated by chlordecone. These results are particularly useful to protect the health of the local population by controlling the fishing and the commercialization of seafood products, potentially contaminated by chlordecone. PMID:25994274

  3. Assessment of the contamination of marine fauna by chlordecone in Guadeloupe and Martinique (Lesser Antilles).

    PubMed

    Dromard, Charlotte R; Bodiguel, Xavier; Lemoine, Soazig; Bouchon-Navaro, Yolande; Reynal, Lionel; Thouard, Emmanuel; Bouchon, Claude

    2016-01-01

    Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. From 2003 to 2013, seven campaigns of samplings have been conducted to evaluate the level of contamination of fish, crustaceans, and mollusks. The present study is the first assessment and the first comparison of the concentrations of chlordecone between marine areas, taxonomic groups, and ecological factors like trophic groups or preferential habitat of fish species. The four most contaminated marine areas are located downstream the contaminated rivers and banana plantations. Crustaceans seemed to be more sensitive to the contamination than fish or mollusks. Finally, when comparing contamination of fish according to their ecology, we found that fish usually living at the border of mangrove and presenting detritivores-omnivores diets were the most contaminated by chlordecone. These results are particularly useful to protect the health of the local population by controlling the fishing and the commercialization of seafood products, potentially contaminated by chlordecone.

  4. IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR CHLORDECONE (KEPONE) (2009 FINAL)

    EPA Science Inventory

    EPA is announcing the release of the final report, Toxicological Review of Chlorodecone (kepone): in support of the Integrated Risk Information System (IRIS). The updated Summary for Chlordecone (kepone) and accompanying Quickview have also been added to the IRIS Database....

  5. Human C1 inhibitor attenuates liver ischemia-reperfusion injury and promotes liver regeneration.

    PubMed

    Saidi, Reza F; Rajeshkumar, Barur; Shariftabrizi, Ahmad; Dresser, Karen; Walter, Otto

    2014-04-01

    Liver ischemia-reperfusion injury (IRI) is a well-known cause of morbidity and mortality after liver transplantation (LT). Activation of the complement system contributes to the pathogenesis of IRI. Effective treatment strategies aimed at reducing hepatic IRI and accelerating liver regeneration could offer major benefits in LT. Herein, we investigated the effect of C1-esterase inhibitor (human) [C1-INH] on IRI and liver regeneration. Mice were subjected to 60-min partial IRI, with or without 70% partial hepatectomy, or CCl4-induced acute liver failure. Before liver injury, the animals were pretreated with intravenous C1-INH or normal saline. Liver IRI was evaluated using serum levels of alanine aminotransferase, serum interleukin-6, and histopathology. Liver samples were stained for specific markers of regeneration (5-bromo-2'-deoxyuridine [BrdU] staining and proliferating cell nuclear antigen [PCNA]). Histology, serum interleukin-6, and alanine aminotransferase release revealed that C1-INH treatment attenuated liver injury compared with controls. Improved animal survival and increased number of BrdU- and PCNA-positive cells were observed in C1-INH-treated animals which underwent IRI + partial hepatectomy or CCl4 injection compared with control group. These data indicate that complement plays a key role in IRI and liver regeneration. C1-INH represents a potential therapeutic strategy to reduce IRI and promote regeneration in LT.

  6. Immobilised monomers of human liver arginase.

    PubMed

    Carvajal, N; Martinez, J; Fernandez, M

    1977-03-15

    Human liver arginase (L-arginine amidinohydrolase, EC 3.5.3.1) was immobilised by attachment to nylon with glutaraldehyde as a crosslinking agent. Incubation of the immobilised tetrameric enzyme with EDTA followed by dialysis resulted in the dissociation of the enzyme into inactive matrix-bound and solubilised subunits. Both species recovered enzymatic activity after incubation with Mn2+, and the activity of the reactivated matrix-bound subunits was nearly 25% of that shown by the enzyme initially attached to the support in the tetrameric form. When the reactivated bound subunits were incubated with soluble subunits in the presence of Mn2+, they 'picked-up' from the solution an amount of protein and enzymatic activity almost identical to that initially lost by the immobilised tetramer after the dissociating treatment with EDTA. This occurred only in the presence of Mn2+. It is suggested that the reactivation of the subunits of arginase involves the initial formation of an active monomer, which then acquires a conformation that favours a reassociation to the tetrameric state. PMID:402942

  7. Human liver microsomal metabolism of (+)-discodermolide.

    PubMed

    Fan, Yun; Schreiber, Emanuel M; Day, Billy W

    2009-10-01

    The polyketide natural product (+)-discodermolide is a potent microtubule stabilizer that has generated considerable interest in its synthetic, medicinal, and biological chemistry. It progressed to early clinical oncology trials, where it showed some efficacy in terms of disease stabilization but also some indications of causing pneumotoxicity. Remarkably, there are no reports of its metabolism. Here, we examined its fate in mixed human liver microsomes. Due to limited availability of the agent, we chose a nanoflow liquid chromatography-electrospray ionization-mass spectrometry analytical approach employing quadrupolar ion trap and quadrupole-quadrupole-time-of-flight instruments for these studies. (+)-Discodermolide was rapidly converted to eight metabolites, with the left-side lactone (net oxidation) and the right-side diene (epoxidation followed by hydrolysis, along with an oxygen insertion product) being the most metabolically labile sites. Other sites of metabolism were the allylic and pendant methyl moieties in the C12-C14 region of the molecule. The results provide information on the metabolic soft spots of the molecule and can be used in further medicinal chemistry efforts to optimize discodermolide analogues.

  8. The Chlordecone crisis in the French West Indies : Its fate in soils and water

    NASA Astrophysics Data System (ADS)

    Voltz, Marc; Cattan, Philippe; Saison, Carine; Berns, Anne E.; Colin, François; Crabit, Armand; Crevoisier, David; Fernandez-Bayo, Jesus; Levillain, Joseph; Pak, Lai-Ting; Samouelian, Anatja; Cabidoche, Yves-Marie

    2013-04-01

    In the French West Indies, chlordecone (CLD), an organochlorine pesticide, which is highly persistent in the environment, was applied in banana plantations from 1972 to 1993 against the banana weevil Cosmopolites sordidus. Pollution surveys conducted in 2001 by the French Department of Health revealed the presence of chlordecone in soils, rivers, springs over large areas in Guadeloupe and Martinique islands. Contamination of drinking water, food crops, aquatic species by CLD has been observed as well as its presence in blood of men, pregnant women and newborns. There is therefore a large social concern about the extent and evolution of CLD pollution in the French West Indies and its impact on human health and ecosystems. From 2008 to 2012 a multidisciplinary project CHLORDEXCO took place to study the CLD fate in water, soils and the contamination characteristics of aquatic species and food crops. Here, we summarize results obtained on the processes controlling the spatial and temporal patterns of soil and water contamination at the scale of the banana cropping area in Guadeloupe and of the Perou catchment. The main soils in the contaminated areas are andosols and nitisols and formed from the weathering of volcanic ashes. They have a high organic carbon content and high content of secondary minerals, allophane for andosols and halloysite for nitisols. An analysis of the spatial distribution of CLD in soil over 1045 field plots showed that the soil type had a strong impact. Andosols, with a high sorption capacity (Koc 20 000 L/kg), had the highest CLD concentrations and stocks, unlike Nitisols, which had 10-fold lower sorption capacities. A significant « farm effect », due to between-farm variations of application times and amounts, was also noticed. The observed stocks of CLD clearly correspond to the accumulation in soil of successive treatments and thereby confirm the high persistence of CLD in soil also observed in incubation studies in soil microcosms. Soil

  9. Mouse liver repopulation with hepatocytes generated from human fibroblasts

    PubMed Central

    Zhu, Saiyong; Rezvani, Milad; Harbell, Jack; Mattis, Aras N.; Wolfe, Alan R.; Benet, Leslie Z.; Willenbring, Holger; Ding, Sheng

    2014-01-01

    Human induced pluripotent stem cells (iPSCs) promise to revolutionize research and therapy of liver diseases by providing a source of hepatocytes for autologous cell therapy and disease modeling. However, despite progress in advancing the differentiation of iPSCs into hepatocytes (iPSC-Heps) in vitro1–3, cells that replicate the ability of human primary adult hepatocytes (aHeps) to proliferate extensively in vivo have not been reported. This deficiency has hampered efforts to recreate human liver diseases in mice, and has cast doubt on the potential of iPSC-Heps for liver cell therapy. The reason is that extensive post-transplant expansion is needed to establish and sustain a therapeutically effective liver cell mass in patients, a lesson learned from clinical trials of aHep transplantation4. As a solution to this problem, we report generation of human fibroblast-derived hepatocytes that can repopulate mouse livers. Unlike current protocols for deriving hepatocytes from human fibroblasts, ours did not generate iPSCs, but shortcut reprogramming to pluripotency to generate an induced multipotent progenitor cell (iMPC) state from which endoderm progenitor cells (iMPC-EPCs) and subsequently hepatocytes (iMPC-Heps) could be efficiently differentiated. For this, we identified small molecules that aided endoderm and hepatocyte differentiation without compromising proliferation. After transplantation into an immune-deficient mouse model of human liver failure, iMPC-Heps proliferated extensively and acquired levels of hepatocyte function similar to aHeps. Unfractionated iMPC-Heps did not form tumors, most likely because they never entered a pluripotent state. To our knowledge, this is the first demonstration of significant liver repopulation of mice with human hepatocytes generated in vitro, which removes a long-standing roadblock on the path to autologous liver cell therapy. PMID:24572354

  10. Characterization of chlordecone-tolerant fungal populations isolated from long-term polluted tropical volcanic soil in the French West Indies.

    PubMed

    Merlin, Chloé; Devers, Marion; Crouzet, Olivier; Heraud, Cécile; Steinberg, Christian; Mougin, Christian; Martin-Laurent, Fabrice

    2014-04-01

    The insecticide chlordecone is a contaminant found in most of the banana plantations in the French West Indies. This study aims to search for fungal populations able to grow on it. An Andosol heavily contaminated with chlordecone, perfused for 1 year in a soil-charcoal system, was used to conduct enrichment cultures. A total of 103 fungal strains able to grow on chlordecone-mineral salt medium were isolated, purified, and deposited in the MIAE collection (Microorganismes d'Intérêt Agro-Environnemental, UMR Agroécologie, Institut National de la Recherche Agronomique, Dijon, France). Internal transcribed spacer sequencing revealed that all isolated strains belonged to the Ascomycota phylum and gathered in 11 genera: Metacordyceps, Cordyceps, Pochonia, Acremonium, Fusarium, Paecilomyces, Ophiocordyceps, Purpureocillium, Bionectria, Penicillium, and Aspergillus. Among predominant species, only one isolate, Fusarium oxysporum MIAE01197, was able to grow in a liquid culture medium that contained chlordecone as sole carbon source. Chlordecone increased F. oxysporum MIAE01197 growth rate, attesting for its tolerance to this organochlorine. Moreover, F. oxysporum MIAE01197 exhibited a higher EC50 value than the reference strain F. oxysporum MIAE00047. This further suggests its adaptation to chlordecone tolerance up to 29.2 mg l(-1). Gas chromatography-mass spectrometry (GC-MS) analysis revealed that 40 % of chlordecone was dissipated in F. oxysporum MIAE01197 suspension culture. No chlordecone metabolite was detected by GC-MS. However, weak amount of (14)CO2 evolved from (14)C10-chlordecone and (14)C10-metabolites were observed. Sorption of (14)C10-chlordecone onto fungal biomass followed a linear relationship (r (2) = 0.99) suggesting that it may also account for chlordecone dissipation in F. oxysporum MIAE01197 culture. PMID:23872892

  11. A microfluidically perfused three dimensional human liver model.

    PubMed

    Rennert, Knut; Steinborn, Sandra; Gröger, Marko; Ungerböck, Birgit; Jank, Anne-Marie; Ehgartner, Josef; Nietzsche, Sandor; Dinger, Julia; Kiehntopf, Michael; Funke, Harald; Peters, Frank T; Lupp, Amelie; Gärtner, Claudia; Mayr, Torsten; Bauer, Michael; Huber, Otmar; Mosig, Alexander S

    2015-12-01

    Within the liver, non-parenchymal cells (NPCs) are critically involved in the regulation of hepatocyte polarization and maintenance of metabolic function. We here report the establishment of a liver organoid that integrates NPCs in a vascular layer composed of endothelial cells and tissue macrophages and a hepatic layer comprising stellate cells co-cultured with hepatocytes. The three-dimensional liver organoid is embedded in a microfluidically perfused biochip that enables sufficient nutrition supply and resembles morphological aspects of the human liver sinusoid. It utilizes a suspended membrane as a cell substrate mimicking the space of Disse. Luminescence-based sensor spots were integrated into the chip to allow online measurement of cellular oxygen consumption. Application of microfluidic flow induces defined expression of ZO-1, transferrin, ASGPR-1 along with an increased expression of MRP-2 transporter protein within the liver organoids. Moreover, perfusion was accompanied by an increased hepatobiliary secretion of 5(6)-carboxy-2',7'-dichlorofluorescein and an enhanced formation of hepatocyte microvilli. From this we conclude that the perfused liver organoid shares relevant morphological and functional characteristics with the human liver and represents a new in vitro research tool to study human hepatocellular physiology at the cellular level under conditions close to the physiological situation.

  12. Proteomics analysis of human nonalcoholic fatty liver.

    PubMed

    Rodriguez-Suarez, Eva; Mato, Jose M; Elortza, Felix

    2012-01-01

    Nonalcoholic fatty liver disease (NAFLD) is being increasingly recognized as a major cause of liver-related morbidity and mortality. Given the increasing prevalence of obesity in western countries, NAFLD has become an important public health problem. The principal aim of this study was to find differences in protein expression between patients with NAFLD and healthy controls. Changes in protein expression of liver samples from controls, nonalcoholic steatosis, and nonalcoholic steatohepatitis (NASH) subjects were analyzed by two-dimensional differential in-gel electrophoresis (DIGE). With this proteomic technique, hundreds of proteins can be analyzed simultaneously and their relative abundance can be calculated. Proteins showing significant changes (ratio ≥ 1.5, p < 0.05) were identified by MALDI TOF/TOF mass spectrometry. Western blot of tissue homogenates was then used as a complementary method to validate protein expression changes observed by DIGE. With the aim to have a noninvasive approach to detect changes produced in NAFLD-affected liver, validated proteins were further tested in serum samples of different cohorts of patients. Following this approach, we identified two candidate markers CPS1 and GRP78 that were differentially expressed between control, steatosis, and NASH. This proteomics approach demonstrates that DIGE combined with MALDI TOF/TOF and Western blot analysis of tissue and serum samples is a useful approach to identify candidate markers associated with NAFLD.

  13. Cold Preservation of Human Adult Hepatocytes for Liver Cell Therapy.

    PubMed

    Duret, Cedric; Moreno, Daniel; Balasiddaiah, Anangi; Roux, Solene; Briolotti, Phillipe; Raulet, Edith; Herrero, Astrid; Ramet, Helene; Biron-Andreani, Christine; Gerbal-Chaloin, Sabine; Ramos, Jeanne; Navarro, Francis; Hardwigsen, Jean; Maurel, Patrick; Aldabe, Rafael; Daujat-Chavanieu, Martine

    2015-01-01

    Hepatocyte transplantation is a promising alternative therapy for the treatment of hepatic failure, hepatocellular deficiency, and genetic metabolic disorders. Hypothermic preservation of isolated human hepatocytes is potentially a simple and convenient strategy to provide on-demand hepatocytes in sufficient quantity and of the quality required for biotherapy. In this study, first we assessed how cold storage in three clinically safe preservative solutions (UW, HTS-FRS, and IGL-1) affects the viability and in vitro functionality of human hepatocytes. Then we evaluated whether such cold-preserved human hepatocytes could engraft and repopulate damaged livers in a mouse model of liver failure. Human hepatocytes showed comparable viabilities after cold preservation in the three solutions. The ability of fresh and cold-stored hepatocytes to attach to a collagen substratum and to synthesize and secrete albumin, coagulation factor VII, and urea in the medium after 3 days in culture was also equally preserved. Cold-stored hepatocytes were then transplanted in the spleen of immunodeficient mice previously infected with adenoviruses containing a thymidine kinase construct and treated with a single dose of ganciclovir to induce liver injury. Engraftment and liver repopulation were monitored over time by measuring the blood level of human albumin and by assessing the expression of specific human hepatic mRNAs and proteins in the recipient livers by RT-PCR and immunohistochemistry, respectively. Our findings show that cold-stored human hepatocytes in IGL-1 and HTS-FRS preservative solutions can survive, engraft, and proliferate in a damaged mouse liver. These results demonstrate the usefulness of human hepatocyte hypothermic preservation for cell transplantation. PMID:25622096

  14. Liver-derived human mesenchymal stem cells: a novel therapeutic source for liver diseases.

    PubMed

    Wang, Yini; Yu, Xiaopeng; Chen, Ermei; Li, Lanuan

    2016-01-01

    Mesenchymal stem cells (MSCs) represent an attractive cell type for research and therapy due to their ability to proliferate, differentiate, modulate immune reactions, and secrete trophic factors. MSCs exist in a multitude of tissues, including bone marrow, umbilical cord, and adipose tissues. Moreover, MSCs have recently been isolated from the liver. Compared with other MSC types, liver-derived human MSCs (LHMSCs) possess general morphologies, immune functions, and differentiation capacities. Interestingly, LHMCSs produce higher levels of pro-angiogenic, anti-inflammatory, and anti-apoptotic cytokines than those of bone marrow-derived MSCs. Thus, these cells may be a promising therapeutic source for liver diseases. This paper summarizes the biological characteristics of LHMSCs and their potential benefits and risks for the treatment of liver diseases. PMID:27176654

  15. ADV36 adipogenic adenovirus in human liver disease

    PubMed Central

    Trovato, Francesca M; Catalano, Daniela; Garozzo, Adriana; Martines, G Fabio; Pirri, Clara; Trovato, Guglielmo M

    2014-01-01

    Obesity and liver steatosis are usually described as related diseases. Obesity is regarded as exclusive consequence of an imbalance between food intake and physical exercise, modulated by endocrine and genetic factors. Non-alcoholic fatty liver disease (NAFLD), is a condition whose natural history is related to, but not completely explained by over-nutrition, obesity and insulin resistance. There is evidence that environmental infections, and notably adipogenic adenoviruses (ADV) infections in humans, are associated not only with obesity, which is sufficiently established, but also with allied conditions, such as fatty liver. In order to elucidate the role, if any, of previous ADV36 infection in humans, we investigated association of ADV36-ADV37 seropositivity with obesity and fatty liver in humans. Moreover, the possibility that lifestyle-nutritional intervention in patients with NAFLD and different ADV36 seropositive status, achieves different clinical outcomes on ultrasound bright liver imaging, insulin resistance and obesity was challenged. ADV36 seropositive patients have a more consistent decrease in insulin resistance, fatty liver severity and body weight in comparison with ADV36 seronegative patients, indicating a greater responsiveness to nutritional intervention. These effects were not dependent on a greater pre-interventional body weight and older age. These results imply that no obvious disadvantage - and, seemingly, that some benefit - is linked to ADV36 seropositivity, at least in NAFLD. ADV36 previous infection can boost weight loss and recovery of insulin sensitivity under interventional treatment. PMID:25356033

  16. 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.

  17. Perhexiline maleate toxicity on human liver cell lines.

    PubMed Central

    Le Gall, J Y; Guillouzo, A; Glaise, D; Deugnier, Y; Messner, M; Bourel, M

    1980-01-01

    When added to the culture medium of human liver cell lines, perhexiline maleate induced formation of numerous myeloid bodies containing unicentric or multicentric smooth membranes within a few days. The nine lysosomal enzyme activities studied, except for beta-galactosidase which decreased, remained unchanged. These results indicate that on cultured human liver cells perhexiline maleate has an effect similar to that described on hepatocytes of some patients treated with this drug and suggest that myeloid body formation is not due to impairment of lysosomal enzyme activities. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7192674

  18. Liver Stem Cells: Experimental Findings and Implications for Human Liver Disease.

    PubMed

    Michalopoulos, George K; Khan, Zahida

    2015-10-01

    Evidence from human histopathology and experimental studies with rodents and zebrafish has shown that hepatocytes and cholangiocytes may function as facultative stem cells for each other in conditions of impaired regeneration. The interpretation of the findings derived from these studies has generated considerable discussion and some controversies. This review examines the evidence obtained from the different experimental models and considers implications that these studies may have for human liver disease.

  19. The mesenchymal transcription factor SNAI-1 instructs human liver specification.

    PubMed

    Goldman, Orit; Valdes, Victor Julian; Ezhkova, Elena; Gouon-Evans, Valerie

    2016-07-01

    Epithelial-mesenchymal transition (EMT) and the mesenchymal-epithelial transition (MET) are processes required for embryo organogenesis. Liver develops from the epithelial foregut endoderm from which the liver progenitors, hepatoblasts, are specified. The migrating hepatoblasts acquire a mesenchymal phenotype to form the liver bud. In mid-gestation, hepatoblasts mature into epithelial structures: the hepatocyte cords and biliary ducts. While EMT has been associated with liver bud formation, nothing is known about its contribution to hepatic specification. We previously established an efficient protocol from human embryonic stem cells (hESC) to generate hepatic cells (Hep cells) resembling the hepatoblasts expressing alpha-fetoprotein (AFP) and albumin (ALB). Here we show that Hep cells express both epithelial (EpCAM and E-cadherin) and mesenchymal (vimentin and SNAI-1) markers. Similar epithelial and mesenchymal hepatoblasts were identified in human and mouse fetal livers, suggesting a conserved interspecies phenotype. Knock-down experiments demonstrated the importance of SNAI-1 in Hep cell hepatic specification. Moreover, ChIP assays revealed direct binding of SNAI-1 in the promoters of AFP and ALB genes consistent with its transcriptional activator function in hepatic specification. Altogether, our hESC-derived Hep cell cultures reveal the dual mesenchymal and epithelial phenotype of hepatoblast-like cells and support the unexpected transcriptional activator role of SNAI-1 in hepatic specification. PMID:27240252

  20. Biomechanical response of human liver in tensile loading.

    PubMed

    Kemper, Andrew R; Santago, Anthony C; Stitzel, Joel D; Sparks, Jessica L; Duma, Stefan M

    2010-01-01

    Motor vehicle collisions commonly result in serious life threatening liver injuries. Although finite element models are becoming an integral tool in the reduction of automotive related liver injuries, the establishment of accurate material models and tissue level tolerance values is critical for accurate injury risk assessment. This study presents a total of 51 tension tests performed on human liver parenchyma at various loading rates in order to characterize the viscoelastic and failure properties of human liver. Standard dog-bone coupons were obtained from fresh human livers and tested within 48 hours of death. Each coupon was tested once to failure at one of four loading rates (0.008 s(-1), 0.089 s(-1), 0.871 s(-1), and 9.477 s(-1)) to investigate the effects of rate dependence. Load and acceleration data were obtained from each of the specimen grips. High-speed video and optical markers placed on the specimens were used to measure local displacement. Failure stress and strain were calculated at the location of failure in the gage length of the coupon. The results of the study showed that liver parenchyma is rate dependent, with higher rate tests giving higher failure stresses and lower failure strains. The failure strains for all tests ranged from 11% to 54% and the failure stresses ranged from 7 kPa to 95 kPa. This study provides novel biomechanical data that can be used in the development of both rate dependent material models and tissue level tolerance values critical for the validation of finite element models used to assess injury risk in automobile collisions. PMID:21050588

  1. Biomechanical Response of Human Liver in Tensile Loading

    PubMed Central

    Kemper, Andrew R.; Santago, Anthony C.; Stitzel, Joel D.; Sparks, Jessica L.; Duma, Stefan M.

    2010-01-01

    Motor vehicle collisions commonly result in serious life threatening liver injuries. Although finite element models are becoming an integral tool in the reduction of automotive related liver injuries, the establishment of accurate material models and tissue level tolerance values is critical for accurate injury risk assessment. This study presents a total of 51 tension tests performed on human liver parenchyma at various loading rates in order to characterize the viscoelastic and failure properties of human liver. Standard dog-bone coupons were obtained from fresh human livers and tested within 48 hours of death. Each coupon was tested once to failure at one of four loading rates (0.008 s–1, 0.089 s–1, 0.871 s–1, and 9.477 s–1) to investigate the effects of rate dependence. Load and acceleration data were obtained from each of the specimen grips. High-speed video and optical markers placed on the specimens were used to measure local displacement. Failure stress and strain were calculated at the location of failure in the gage length of the coupon. The results of the study showed that liver parenchyma is rate dependent, with higher rate tests giving higher failure stresses and lower failure strains. The failure strains for all tests ranged from 11% to 54% and the failure stresses ranged from 7 kPa to 95 kPa. This study provides novel biomechanical data that can be used in the development of both rate dependent material models and tissue level tolerance values critical for the validation of finite element models used to assess injury risk in automobile collisions. PMID:21050588

  2. Methods of Liver Stem Cell Therapy in Rodents as Models of Human Liver Regeneration in Hepatic Failure.

    PubMed

    Hashemi Goradel, Nasser; Darabi, Masoud; Shamsasenjan, Karim; Ejtehadifar, Mostafa; Zahedi, Sarah

    2015-09-01

    Cell therapy is a promising intervention for treating liver diseases and liver failure. Different animal models of human liver cell therapy have been developed in recent years. Rats and mice are the most commonly used liver failure models. In fact, rodent models of hepatic failure have shown significant improvement in liver function after cell infusion. With the advent of stem-cell technologies, it is now possible to re-programme adult somatic cells such as skin or hair-follicle cells from individual patients to stem-like cells and differentiate them into liver cells. Such regenerative stem cells are highly promising in the personalization of cell therapy. The present review article will summarize current approaches to liver stem cell therapy with rodent models. In addition, we discuss common cell tracking techniques and how tracking data help to direct liver cell therapy research in animal models of hepatic failure.

  3. Distribution of elastic system fibres in human fetal liver.

    PubMed Central

    Monte, A; Costa, A; Porto, L C

    1996-01-01

    Elastic system fibres are extracellular matrix components found in different organs for which they provide elasticity and some mechanical resistance. Oxytalan, elaunin and elastic fibres, which possess graduated amounts of elastin, are the 3 forms of elastic system fibres that are identifiable by their tinctorial and ultrastructural features. The distribution of these fibres in adult human liver is well-established but little, if anything, is known about them in fetal liver. The distribution of elastic system fibres was therefore investigated in human fetal liver, and the process of elastogenesis characterised. Specimens of liver from 24 human fetuses ranging in age from 13 to 38 wk postfertilisation were studied. The results are presented in relation to gestational age and the size of the portal tracts. Portal tracts exhibited a network of oxytalan fibres at 13 wk; elaunin fibres appeared later after 20 wk postfertilisation. Elastogenesis occurred more rapidly in venous than in arterial walls, and in veins it was more evident in the adventitia. A microfibrillar network of oxytalan fibres was observed around biliary ducts from the outset of their development. Elastogenesis follows the sequence oxytalan, elaunin and elastic fibres, but the elastogenetic process only completes its maturation in arterial walls, thus leading to the internal elastic lamina. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8763481

  4. Human Liver Transplantation As A Model To Study HCV Pathogenesis

    PubMed Central

    Hughes, Michael G.; Rosen, Hugo R.

    2010-01-01

    Hepatitis C is a leading etiology of liver cancer and cause for liver transplantation. Although new therapies have improved the rates of sustained response, a large proportion of patients (~50%) fail to respond to antiviral treatment, thus remaining at risk for disease progression. While chimpanzees have been used to study HCV biology and treatments, their cost is quite high and their use is strictly regulated; indeed, the NIH no longer supports the breeding of chimpanzees for study. The development of HCV therapies has been hindered by the relative paucity of small animal models to study HCV pathogenesis. This review presents the strengths of the human liver transplant, highlighting the advances derived from this model, including insights into viral kinetics and quasispecies, viral receptor binding and entry, innate and adaptive immunity. Moreover, consideration is made of current and emerging antiviral therapeutic approaches based on translational research results. PMID:19877210

  5. Colchicine antimitosis abolishes resiliency of postnatally developing rats to chlordecone-amplified carbon tetrachloride hepatotoxicity and lethality.

    PubMed Central

    Dalu, A; Rao, P S; Mehendale, H M

    1998-01-01

    We have previously reported that rats are resilient to the hepatotoxic and lethal combination of chlordecone (CD) and carbon tetrachloride (CCl4) during early postnatal development. The overall findings pointed to stimulated cell division and tissue repair mechanisms as the underlying cause of resistance. The objective of the current study was to investigate if the antimitotic effect of colchicine (CLC) abolishes this resiliency to CD + CCl4 by inhibiting ongoing and stimulated cell division. We used 45-day-old rats in this study because this age group exhibited partial sensitivity to CD + CCl4 in our previous studies. Male Sprague-Dawley rats were treated with a single low intraperitoneal dose of CCl4 (100 microl/kg) or corn oil after exposure to either 10 ppm CD in the diet or a normal diet (ND) for 15 days. CLC (1 mg/kg) was administered 6 or 30 hr after CCl4 to ND or CD rats, respectively. Administration of CLC resulted in increased CCl4-induced mortality from 25% to 85% in rats pretreated with CD, in contrast to 100% survival in ND rats. Liver injury was assessed by plasma alanine transaminase (ALT) and sorbitol dehydrogenase (SDH) elevations as well as by histopathology. Hepatocellular regeneration was assessed by 3H-thymidine (3H-T) incorporation into hepatonuclear DNA and proliferating cell nuclear antigen (PCNA) studies during 0-96 hr after CCl4. Administration of CLC to ND + CCl4 rats resulted in a slight delay in cell division and tissue repair, as indicated by 3H-T incorporation and PCNA, thereby leading to prolonged liver injury as revealed by elevations in plasma ALT, SDH, and histopathological lesions. In contrast, CLC administration to CD + CCl4-treated rats further delayed and diminished cell division by 80%, which led to unrestrained progression of CCl4-induced liver injury, resulting in 85% mortality. These findings underscore the importance of ongoing and toxicant-stimulated cell division and tissue repair mechanisms in hepatotoxicity, and the

  6. Cloning and expression of special F protein from human liver

    PubMed Central

    Liu, Shu-Ye; Yu, Xin-Da; Song, Chun-Juan; Lu, Wei; Zhang, Jian-Dong; Shi, Xin-Rong; Duan, Ying; Zhang, Ju

    2007-01-01

    AIM: To clone human liver special F protein and to express it in a prokaryotic system. METHODS: Total RNA was isolated from human liver tissue and first-strand cDNA was reverse transcribed using the PCR reverse primer. Following this, cDNA of the F protein was ligated into the clone vector pUCm-T. The segment of F protein’s cDNA was subcloned into the expression vector pET-15b and transformed into E. coli BL21 (DE3) pLyss. Isopropy-β-D-thiogalactoside (IPTG) was then used to induce expression of the target protein. RESULTS: The cDNA clone of human liver special F protein (1134bp) was successfully produced, with the cDNA sequence being published in Gene-bank: DQ188836. We confirmed the expression of F protein by Western blot with a molecular weight of 43 kDa. The expressed protein accounted for 40% of the total protein extracted. CONCLUSION: F protein expresses cDNA clone in a prokaryotic system, which offers a relatively simple way of producing sufficient quantities of F protein and contributes to understanding the principal biological functions of this protein. PMID:17465469

  7. Role of liver transplantation in human immunodeficiency virus positive patients

    PubMed Central

    Joshi, Deepak; Agarwal, Kosh

    2015-01-01

    End-stage liver disease (ESLD) is a leading cause of morbidity and mortality amongst human immunodeficiency virus (HIV)-positive individuals. Chronic hepatitis B and hepatitis C virus (HCV) infection, drug-induced hepatotoxicity related to combined anti-retro-viral therapy, alcohol related liver disease and non-alcohol related fatty liver disease appear to be the leading causes. It is therefore, anticipated that more HIV-positive patients with ESLD will present as potential transplant candidates. HIV infection is no longer a contraindication to liver transplantation. Key transplantation outcomes such as rejection and infection rates as well as medium term graft and patient survival match those seen in the non-HIV infected patients in the absence of co-existing HCV infection. HIV disease does not seem to be negatively impacted by transplantation. However, HIV-HCV co-infection transplant outcomes remain suboptimal due to recurrence. In this article, we review the key challenges faced by this patient cohort in the pre- and post-transplant period. PMID:26604639

  8. The invasive lionfish, Pterois volitans, used as a sentinel species to assess the organochlorine pollution by chlordecone in Guadeloupe (Lesser Antilles).

    PubMed

    Charlotte, Dromard R; Yolande, Bouchon-Navaro; Cordonnier, Sebastien; Claude, Bouchon

    2016-06-15

    In Guadeloupe, many marine organisms are affected by an organochlorine pollution used in the past by the banana industry to fight against the banana weevil. In the present study, we evaluated the level of contamination of the invasive Indo-Pacific lionfish, Pterois volitans, all around the island. Concentrations of chlordecone varied from 3 to 144μg.kg(-1) wet weight. The highest concentrations were recorded when samples were captured in the marine zones located downstream of the previous banana plantations. This contamination seemed to decrease rapidly with the distance from the coast. Mean concentration of chlordecone in Pterois volitans was higher than that of five other fish species collected in similar sites. Due to its position at the top of the trophic web, lionfish was affected by bioaccumulation of chlordecone and can be used as a sentinel species to assess and control the level of contamination of the marine environment by chlordecone.

  9. Phantom and animal tissues for modelling the electrical properties of human liver.

    PubMed

    Stauffer, P R; Rossetto, F; Prakash, M; Neuman, D G; Lee, T

    2003-01-01

    The dielectric properties of human liver were characterized over the frequency range of 0.3-3 GHz for freshly excised tissue samples of primary hepatocellular carcinoma, metastatic colorectal carcinoma, and normal liver tissues resected from the tumour margin. On average, the dielectric constant (epsilon(r)) of freshly excised human liver tumour was 12% higher than that of surrounding normal liver, and the electrical conductivity (sigma) of tumour was 24% higher. In order to establish suitable tissue models for human liver, the electrical properties were compared to measurements of homogenous phantom mixtures, in vitro bovine liver, and in vivo canine and porcine liver tissues. The data demonstrate that there are several animal tissues that can be used to model the average dielectric properties of human liver reasonably accurately, and use of the most readily available bovine liver appears well-justified, even when stored for up to 10 days in a refrigerator. Additionally, the dielectric properties of in vitro liver remained stable over a large temperature range, with sigma rising only 1.1%/ degrees C in porcine liver (15-37 degrees C) and 2.0%/ degrees C in bovine liver (10-90 degrees C), and epsilon(r) decreasing < or =0.2%/ degrees C in both tissues. This effort identifies homogeneous solid and liquid phantom models and several heterogeneous in vitro tissues that adequately model the dielectric properties of human liver tumours for use in quantitative studies of microwave power deposition in liver.

  10. Liver stem cells: Experimental findings and implications for human liver disease

    PubMed Central

    2015-01-01

    Evidence from human histopathology and experimental studies with rodents and zebrafish has shown that hepatocytes and cholangiocytes may function as facultative stem cells for each other in conditions of impaired regeneration. The interpretation of the findings derived from these studies has generated considerable discussion and some controversies. This review examines the evidence obtained from the different experimental models and considers implications that these studies may have for human liver disease. Few topics of liver tissue biology have attracted as much attention as the existence of liver-specific tissue stem cells. Routine liver histology reveals two types of epithelial cells, hepatocytes and cholangiocytes (also known as biliary epithelial cells). Endothelial cells line the hepatic capillaries (sinusoids), with macrophages (Kupffer cells) interspersed along the sinusoid lumen. Stellate cells exist under the sinusoids and in close proximity to hepatocytes. None of these cells appears to have functions of a fully committed tissue specific stem cell, analogous to the cells of the intestinal crypts, the basal layer of the epidermis, bone marrow stem cells, etc. Hepatocytes and cholangiocytes can be easily identified based on their morphology and cell-specific biomarkers. Hepatocytes and cholangiocytes, however, often have mutually mixed expression of biomarkers in pathologic conditions. In patients with fulminant hepatic failure (FHF), there is rampant proliferation of cholangiocytes organized in ductular structures (“ductular reaction”1, 2). Many of these cholangiocytes (known as ductular hepatocytes) express biomarkers associated with hepatocytes, (HNF4, albumin, HEPPAR3, etc.). They are seen surrounding cells ranging in size from small to typical hepatocytes, and with a gradient of expression of cholangiocyte-associated biomarkers (e.g. EpCAM) decreasing from the periphery to the center (Regenerative Clusters: see Figure 1). It is not clear in FHF

  11. Interaction of rocuronium with human liver cytochromes P450.

    PubMed

    Anzenbacherova, Eva; Spicakova, Alena; Jourova, Lenka; Ulrichova, Jitka; Adamus, Milan; Bachleda, Petr; Anzenbacher, Pavel

    2015-02-01

    Rocuronium is a neuromuscular blocking agent acting as a competitive antagonist of acetylcholine. Results of an inhibition of eight individual liver microsomal cytochromes P450 (CYP) are presented. As the patients are routinely premedicated with diazepam, possible interaction of diazepam with rocuronium has been also studied. Results indicated that rocuronium interacts with human liver microsomal CYPs by binding to the substrate site. Next, concentration dependent inhibition of liver microsomal CYP3A4 down to 42% (at rocuronium concentration 189 μM) was found. This effect has been confirmed with two CYP3A4 substrates, testosterone (formation of 6β-hydroxytestosterone) and diazepam (temazepam formation). CYP2C9 and CYP2C19 activities were inhibited down to 75-80% (at the same rocuronium concentration). Activities of other microsomal CYPs have not been inhibited by rocuronium. To prove the possibility of rocuronium interaction with other drugs (diazepam), the effect of rocuronium on formation of main diazepam metabolites, temazepam (by CYP3A4) and desmethyldiazepam, (also known as nordiazepam; formed by CYP2C19) in primary culture of human hepatocytes has been examined. Rocuronium has caused inhibition of both reactions by 20 and 15%, respectively. The results open a possibility that interactions of rocuronium with drugs metabolized by CYP3A4 (and possibly also CYP2C19) may be observed.

  12. Uptake and cytotoxicity of chitosan nanoparticles in human liver cells

    SciTech Connect

    Loh, Jing Wen; Yeoh, George; Saunders, Martin; Lim, Lee-Yong

    2010-12-01

    Despite extensive research into the biomedical and pharmaceutical applications of nanoparticles, and the liver being the main detoxifying organ in the human body, there are limited studies which delineate the hepatotoxicity of nanoparticles. This paper reports on the biological interactions between liver cells and chitosan nanoparticles, which have been widely recognised as biocompatible. Using the MTT assay, human liver cells were shown to tolerate up to 4 h of exposure to 0.5% w/v of chitosan nanoparticles (18 {+-} 1 nm, 7.5 {+-} 1.0 mV in culture medium). At nanoparticle concentrations above 0.5% w/v, cell membrane integrity was compromised as evidenced by leakage of alanine transaminase into the extracellular milieu, and there was a dose-dependent increase in CYP3A4 enzyme activity. Uptake of chitosan nanoparticles into the cell nucleus was observed by confocal microscopic analysis after 4 h exposure with 1% w/v of chitosan nanoparticles. Electron micrographs further suggest necrotic or autophagic cell death, possibly caused by cell membrane damage and resultant enzyme leakage.

  13. Human metabolism of arsenolipids present in cod liver.

    PubMed

    Schmeisser, Ernst; Goessler, Walter; Francesconi, Kevin A

    2006-05-01

    We report results from the first investigation of the human metabolism of arsenic-containing lipids (arsenolipids), significant arsenic constituents of some seafood products. Two male volunteers ingested canned cod liver and the arsenic metabolites in their urine were monitored by high-performance liquid chromatography inductively coupled plasma mass spectrometry over a 66-h period. Volunteer A consumed 85 g (wet mass) of cod liver containing a total of approximately 120 microg arsenic, 77% of which was present as arsenolipids, and volunteer B consumed 85 g (wet mass) of cod liver, 25% of which was present as arsenolipids, together with 20 g of cod liver oil, containing a total of about 180 microg arsenic. The structures of the arsenolipids are currently unknown, whereas the majority of the non-lipid arsenic in the cod liver was identified as arsenobetaine, which was excreted unchanged. The arsenolipids were rapidly metabolised to water-soluble compounds and excreted in the urine; peak arsenic concentrations were recorded between 7 and 15 h (volunteer A) and between 6.5 and 15 h (volunteer B), and by the end of the experiment about 90% of the ingested arsenic had been accounted for in the urine for both volunteers. The major arsenolipid metabolite was dimethylarsinate (DMA), constituting 73% (volunteer A) or 41% (volunteer B) of the total urinary arsenic, and most of the remaining arsenolipid-derived arsenic, constituting about 10% (volunteer A) and 5% (volunteer B), comprised four novel arsenic-containing fatty acids, namely oxo-dimethylarsenopropanoic acid, thio-dimethylarsenopropanoic acid, oxo-dimethylarsenobutanoic acid, and thio-dimethylarsenobutanoic acid. Unchanged arsenobetaine (15% for volunteer A and 51% for volunteer B) made up the remaining urinary arsenic together with trace quantities of other, mostly unknown, arsenicals. In a second experiment (volunteer A only), performed with pure cod liver oil, which contains only arsenolipids, DMA and the same

  14. Radionuclide imaging of the liver in human fascioliasis

    SciTech Connect

    Rivera, J.V.; Bermudez, R.H.

    1984-08-01

    The clinical, laboratory, and scintigraphic findings in four cases of human fascioliasis are described. Acute onset of fever, abdominal pain, and weight loss in a person who has ingested watercress constitutes the clinical syndrome often seen. Eosinophilia and alteration in liver function tests, particularly alkaline phosphatase are frequent. Tc-99m sulfur colloid images showed hepatomegaly in four patients, focal defects in two, splenomegaly in three, and increased splenic uptake in two. Gallium citrate (Ga 67) images show increased uptake in the focal lesions in two of two. Sonographic imaging showed focal lucent abnormality in one of three. Liver biopsy findings were nonspecific. The differential diagnosis from other invasive parasitic diseases is discussed. A possible role of hepatic imaging in the evaluation of fascioliasis is suggested.

  15. Human Liver Infection in a Dish: Easy-To-Build 3D Liver Models for Studying Microbial Infection

    PubMed Central

    Petropolis, Debora B.; Faust, Daniela M.; Tolle, Matthieu; Rivière, Lise; Valentin, Tanguy; Neuveut, Christine; Hernandez-Cuevas, Nora; Dufour, Alexandre; Olivo-Marin, Jean-Christophe; Guillen, Nancy

    2016-01-01

    Human liver infection is a major cause of death worldwide, but fundamental studies on infectious diseases affecting humans have been hampered by the lack of robust experimental models that accurately reproduce pathogen-host interactions in an environment relevant for the human disease. In the case of liver infection, one consequence of this absence of relevant models is a lack of understanding of how pathogens cross the sinusoidal endothelial barrier and parenchyma. To fill that gap we elaborated human 3D liver in vitro models, composed of human liver sinusoidal endothelial cells (LSEC) and Huh-7 hepatoma cells as hepatocyte model, layered in a structure mimicking the hepatic sinusoid, which enable studies of key features of early steps of hepatic infection. Built with established cell lines and scaffold, these models provide a reproducible and easy-to-build cell culture approach of reduced complexity compared to animal models, while preserving higher physiological relevance compared to standard 2D systems. For proof-of-principle we challenged the models with two hepatotropic pathogens: the parasitic amoeba Entamoeba histolytica and hepatitis B virus (HBV). We constructed four distinct setups dedicated to investigating specific aspects of hepatic invasion: 1) pathogen 3D migration towards hepatocytes, 2) hepatocyte barrier crossing, 3) LSEC and subsequent hepatocyte crossing, and 4) quantification of human hepatic virus replication (HBV). Our methods comprise automated quantification of E. histolytica migration and hepatic cells layer crossing in the 3D liver models. Moreover, replication of HBV virus occurs in our virus infection 3D liver model, indicating that routine in vitro assays using HBV or others viruses can be performed in this easy-to-build but more physiological hepatic environment. These results illustrate that our new 3D liver infection models are simple but effective, enabling new investigations on infectious disease mechanisms. The better

  16. Human Liver Infection in a Dish: Easy-To-Build 3D Liver Models for Studying Microbial Infection.

    PubMed

    Petropolis, Debora B; Faust, Daniela M; Tolle, Matthieu; Rivière, Lise; Valentin, Tanguy; Neuveut, Christine; Hernandez-Cuevas, Nora; Dufour, Alexandre; Olivo-Marin, Jean-Christophe; Guillen, Nancy

    2016-01-01

    Human liver infection is a major cause of death worldwide, but fundamental studies on infectious diseases affecting humans have been hampered by the lack of robust experimental models that accurately reproduce pathogen-host interactions in an environment relevant for the human disease. In the case of liver infection, one consequence of this absence of relevant models is a lack of understanding of how pathogens cross the sinusoidal endothelial barrier and parenchyma. To fill that gap we elaborated human 3D liver in vitro models, composed of human liver sinusoidal endothelial cells (LSEC) and Huh-7 hepatoma cells as hepatocyte model, layered in a structure mimicking the hepatic sinusoid, which enable studies of key features of early steps of hepatic infection. Built with established cell lines and scaffold, these models provide a reproducible and easy-to-build cell culture approach of reduced complexity compared to animal models, while preserving higher physiological relevance compared to standard 2D systems. For proof-of-principle we challenged the models with two hepatotropic pathogens: the parasitic amoeba Entamoeba histolytica and hepatitis B virus (HBV). We constructed four distinct setups dedicated to investigating specific aspects of hepatic invasion: 1) pathogen 3D migration towards hepatocytes, 2) hepatocyte barrier crossing, 3) LSEC and subsequent hepatocyte crossing, and 4) quantification of human hepatic virus replication (HBV). Our methods comprise automated quantification of E. histolytica migration and hepatic cells layer crossing in the 3D liver models. Moreover, replication of HBV virus occurs in our virus infection 3D liver model, indicating that routine in vitro assays using HBV or others viruses can be performed in this easy-to-build but more physiological hepatic environment. These results illustrate that our new 3D liver infection models are simple but effective, enabling new investigations on infectious disease mechanisms. The better

  17. Human Liver Infection in a Dish: Easy-To-Build 3D Liver Models for Studying Microbial Infection.

    PubMed

    Petropolis, Debora B; Faust, Daniela M; Tolle, Matthieu; Rivière, Lise; Valentin, Tanguy; Neuveut, Christine; Hernandez-Cuevas, Nora; Dufour, Alexandre; Olivo-Marin, Jean-Christophe; Guillen, Nancy

    2016-01-01

    Human liver infection is a major cause of death worldwide, but fundamental studies on infectious diseases affecting humans have been hampered by the lack of robust experimental models that accurately reproduce pathogen-host interactions in an environment relevant for the human disease. In the case of liver infection, one consequence of this absence of relevant models is a lack of understanding of how pathogens cross the sinusoidal endothelial barrier and parenchyma. To fill that gap we elaborated human 3D liver in vitro models, composed of human liver sinusoidal endothelial cells (LSEC) and Huh-7 hepatoma cells as hepatocyte model, layered in a structure mimicking the hepatic sinusoid, which enable studies of key features of early steps of hepatic infection. Built with established cell lines and scaffold, these models provide a reproducible and easy-to-build cell culture approach of reduced complexity compared to animal models, while preserving higher physiological relevance compared to standard 2D systems. For proof-of-principle we challenged the models with two hepatotropic pathogens: the parasitic amoeba Entamoeba histolytica and hepatitis B virus (HBV). We constructed four distinct setups dedicated to investigating specific aspects of hepatic invasion: 1) pathogen 3D migration towards hepatocytes, 2) hepatocyte barrier crossing, 3) LSEC and subsequent hepatocyte crossing, and 4) quantification of human hepatic virus replication (HBV). Our methods comprise automated quantification of E. histolytica migration and hepatic cells layer crossing in the 3D liver models. Moreover, replication of HBV virus occurs in our virus infection 3D liver model, indicating that routine in vitro assays using HBV or others viruses can be performed in this easy-to-build but more physiological hepatic environment. These results illustrate that our new 3D liver infection models are simple but effective, enabling new investigations on infectious disease mechanisms. The better

  18. 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.

  19. 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

  20. 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

  1. Liver X Receptor (LXR) Regulates Human Adipocyte Lipolysis*

    PubMed Central

    Stenson, Britta M.; Rydén, Mikael; Venteclef, Nicolas; Dahlman, Ingrid; Pettersson, Annie M. L.; Mairal, Aline; Åström, Gaby; Blomqvist, Lennart; Wang, Victoria; Jocken, Johan W. E.; Clément, Karine; Langin, Dominique; Arner, Peter; Laurencikiene, Jurga

    2011-01-01

    The Liver X receptor (LXR) is an important regulator of carbohydrate and lipid metabolism in humans and mice. We have recently shown that activation of LXR regulates cellular fuel utilization in adipocytes. In contrast, the role of LXR in human adipocyte lipolysis, the major function of human white fat cells, is not clear. In the present study, we stimulated in vitro differentiated human and murine adipocytes with the LXR agonist GW3965 and observed an increase in basal lipolysis. Microarray analysis of human adipocyte mRNA following LXR activation revealed an altered gene expression of several lipolysis-regulating proteins, which was also confirmed by quantitative real-time PCR. We show that expression and intracellular localization of perilipin1 (PLIN1) and hormone-sensitive lipase (HSL) are affected by GW3965. Although LXR activation does not influence phosphorylation status of HSL, HSL activity is required for the lipolytic effect of GW3965. This effect is abolished by PLIN1 knockdown. In addition, we demonstrate that upon activation, LXR binds to the proximal regions of the PLIN1 and HSL promoters. By selective knock-down of either LXR isoform, we show that LXRα is the major isoform mediating the lipolysis-related effects of LXR. In conclusion, the present study demonstrates that activation of LXRα up-regulates basal human adipocyte lipolysis. This is at least partially mediated through LXR binding to the PLIN1 promoter and down-regulation of PLIN1 expression. PMID:21030586

  2. Liver X receptor (LXR) regulates human adipocyte lipolysis.

    PubMed

    Stenson, Britta M; Rydén, Mikael; Venteclef, Nicolas; Dahlman, Ingrid; Pettersson, Annie M L; Mairal, Aline; Aström, Gaby; Blomqvist, Lennart; Wang, Victoria; Jocken, Johan W E; Clément, Karine; Langin, Dominique; Arner, Peter; Laurencikiene, Jurga

    2011-01-01

    The Liver X receptor (LXR) is an important regulator of carbohydrate and lipid metabolism in humans and mice. We have recently shown that activation of LXR regulates cellular fuel utilization in adipocytes. In contrast, the role of LXR in human adipocyte lipolysis, the major function of human white fat cells, is not clear. In the present study, we stimulated in vitro differentiated human and murine adipocytes with the LXR agonist GW3965 and observed an increase in basal lipolysis. Microarray analysis of human adipocyte mRNA following LXR activation revealed an altered gene expression of several lipolysis-regulating proteins, which was also confirmed by quantitative real-time PCR. We show that expression and intracellular localization of perilipin1 (PLIN1) and hormone-sensitive lipase (HSL) are affected by GW3965. Although LXR activation does not influence phosphorylation status of HSL, HSL activity is required for the lipolytic effect of GW3965. This effect is abolished by PLIN1 knockdown. In addition, we demonstrate that upon activation, LXR binds to the proximal regions of the PLIN1 and HSL promoters. By selective knock-down of either LXR isoform, we show that LXRα is the major isoform mediating the lipolysis-related effects of LXR. In conclusion, the present study demonstrates that activation of LXRα up-regulates basal human adipocyte lipolysis. This is at least partially mediated through LXR binding to the PLIN1 promoter and down-regulation of PLIN1 expression. PMID:21030586

  3. Trefoil factor-3 expression in human colon cancer liver metastasis.

    PubMed

    Babyatsky, Mark; Lin, Jing; Yio, Xianyang; Chen, Anli; Zhang, Jie-yu; Zheng, Yan; Twyman, Christina; Bao, Xiuliang; Schwartz, Myron; Thung, Swan; Lawrence Werther, J; Itzkowitz, Steven

    2009-01-01

    Deaths from colorectal cancer are often due to liver metastasis. Trefoil factor-3 (TFF3) is expressed by normal intestinal epithelial cells and its expression is maintained throughout the colon adenoma-carcinoma sequence. Our previous work demonstrated a correlation between TFF3 expression and metastatic potential in an animal model of colon cancer. The aim of this study was to determine whether TFF3 is expressed in human colon cancer liver metastasis (CCLM) and whether inhibiting TFF3 expression in colon cancer cells would alter their invasive potential in vitro. Human CCLMs were analyzed at the mRNA and protein level for TFF3 expression. Two highly metastatic rat colon cancer cell lines that either natively express TFF3 (LN cells) or were transfected with TFF3 (LPCRI-2 cells), were treated with two rat TFF3 siRNA constructs (si78 and si365), and analyzed in an in vitro invasion assay. At the mRNA and protein level, TFF3 was expressed in 17/17 (100%) CCLMs and 10/11 (91%) primary colon cancers, but not in normal liver tissue. By real time PCR, TFF3 expression was markedly inhibited by both siRNA constructs in LN and LPCRI-2 cells. The si365 and si78 constructs inhibited invasion by 44% and 53%, respectively, in LN cells, and by 74% and 50%, respectively, in LPCRI-2 cells. These results provide further evidence that TFF3 contributes to the malignant behavior of colon cancer cells. These observations may have relevance for designing new diagnostic and treatment approaches to colorectal cancer.

  4. In vivo liver regeneration potential of human induced pluripotent stem cells from diverse origins.

    PubMed

    Liu, Hua; Kim, Yonghak; Sharkis, Saul; Marchionni, Luigi; Jang, Yoon-Young

    2011-05-11

    Human induced pluripotent stem cells (iPSCs) are a potential source of hepatocytes for liver transplantation to treat end-stage liver disease. In vitro differentiation of human iPSCs into hepatic cells has been achieved using a multistage differentiation protocol, but whether these cells are functional and capable of engrafting and regenerating diseased liver tissue is not clear. We show that human iPSC-derived hepatic cells at various differentiation stages can engraft the liver in a mouse transplantation model. Using the same differentiation and transplantation protocols, we also assessed the ability of human iPSCs derived from each of the three developmental germ layer tissues (that is, ectoderm, mesoderm, and endoderm) to regenerate mouse liver. These iPSC lines, with similar but distinct global DNA methylation patterns, differentiated into multistage hepatic cells with an efficiency similar to that of human embryonic stem cells. Human hepatic cells at various differentiation stages derived from iPSC lines of different origins successfully repopulated the liver tissue of mice with liver cirrhosis. They also secreted human-specific liver proteins into mouse blood at concentrations comparable to that of proteins secreted by human primary hepatocytes. Our results demonstrate the engraftment and liver regenerative capabilities of human iPSC-derived multistage hepatic cells in vivo and suggest that human iPSCs of distinct origins and regardless of their parental epigenetic memory can efficiently differentiate along the hepatic lineage.

  5. Application of chimeric mice with humanized liver for study of human-specific drug metabolism.

    PubMed

    Bateman, Thomas J; Reddy, Vijay G B; Kakuni, Masakazu; Morikawa, Yoshio; Kumar, Sanjeev

    2014-06-01

    Human-specific or disproportionately abundant human metabolites of drug candidates that are not adequately formed and qualified in preclinical safety assessment species pose an important drug development challenge. Furthermore, the overall metabolic profile of drug candidates in humans is an important determinant of their drug-drug interaction susceptibility. These risks can be effectively assessed and/or mitigated if human metabolic profile of the drug candidate could reliably be determined in early development. However, currently available in vitro human models (e.g., liver microsomes, hepatocytes) are often inadequate in this regard. Furthermore, the conduct of definitive radiolabeled human ADME studies is an expensive and time-consuming endeavor that is more suited for later in development when the risk of failure has been reduced. We evaluated a recently developed chimeric mouse model with humanized liver on uPA/SCID background for its ability to predict human disposition of four model drugs (lamotrigine, diclofenac, MRK-A, and propafenone) that are known to exhibit human-specific metabolism. The results from these studies demonstrate that chimeric mice were able to reproduce the human-specific metabolite profile for lamotrigine, diclofenac, and MRK-A. In the case of propafenone, however, the human-specific metabolism was not detected as a predominant pathway, and the metabolite profiles in native and humanized mice were similar; this was attributed to the presence of residual highly active propafenone-metabolizing mouse enzymes in chimeric mice. Overall, the data indicate that the chimeric mice with humanized liver have the potential to be a useful tool for the prediction of human-specific metabolism of xenobiotics and warrant further investigation.

  6. Development of a New Diagnostic System for Human Liver Diseases Based on Conventional Ultrasonic Diagnostic Equipment

    NASA Astrophysics Data System (ADS)

    Kikuchi, Tsuneo; Nakazawa, Toshihiro; Harada, Akimitsu; Sato, Hiroaki; Maruyama, Yukio; Sato, Sojun

    2001-05-01

    In this paper, the authors present the experimental results of using a quantitative ultrasonic diagnosis technique for human liver diseases using the fractal dimension (FD) of the shape of the power spectra (PS) of RF signals. We have developed an experimental system based on a conventional ultrasonic diagnostic system. As a result, we show that normal livers, fatty livers and liver cirrhosis can be identified using the FD values.

  7. Interaction of human lactoferrin with the rat liver

    SciTech Connect

    Debanne, M.T.; Regoeczi, E.; Sweeney, G.D.; Krestynski, F.

    1985-04-01

    Binding of human lactoferrin (hLf) by purified rat liver plasma membranes was studied to clarify whether the liver possesses specific hLf receptors. The binding was rapid between 4 degrees and 37 degrees C, with a pH optimum close to 5.0. At 22 degrees C and in glycine-NaOH (5 mM, pH 7.4) containing 150 mM NaCl and 0.5% albumin, 1 microgram of membrane bound a maximum of 11.8 ng hLf. The dissociation constant of the interaction was 1.6 X 10(-7) M. Other proteins of high isoelectric points (lactoperoxidase, lysozyme, and particularly salmine sulfate) and a piperazine derivative inhibited hLf binding in a concentration- dependent manner. In contrast, monosaccharides (galactose, N- acetylgalactosamine, mannose, and fucose) were ineffective. By omitting NaCl from the incubation buffer, binding was increased 3.6-fold. Erythrocyte ghosts bound hLf less firmly and alveolar macrophages more firmly than hepatic plasma membranes. Liver cell fractionations performed after the intravenous injection of labeled hLf showed that approximately 88% of the hepatic radioligand was associated with parenchymal cells. When binding was expressed per unit of cell volume, however, more hLf was present in nonparenchymal than in parenchymal cells, implying that the above value was determined by the relative cell masses rather than affinities alone. It is concluded that the binding of hLf by hepatic plasma membranes is electrostatic, i.e., is mediated by the cationic nature of the ligand, and that it is explicable in terms of a ''specific nonreceptor interaction'' of the generalized type proposed by Cuatrecasas and Hollenberg.

  8. Epigenomic Landscape of Human Fetal Brain, Heart, and Liver.

    PubMed

    Yan, Liying; Guo, Hongshan; Hu, Boqiang; Li, Rong; Yong, Jun; Zhao, Yangyu; Zhi, Xu; Fan, Xiaoying; Guo, Fan; Wang, Xiaoye; Wang, Wei; Wei, Yuan; Wang, Yan; Wen, Lu; Qiao, Jie; Tang, Fuchou

    2016-02-26

    The epigenetic regulation of spatiotemporal gene expression is crucial for human development. Here, we present whole-genome chromatin immunoprecipitation followed by high throughput DNA sequencing (ChIP-seq) analyses of a wide variety of histone markers in the brain, heart, and liver of early human embryos shortly after their formation. We identified 40,181 active enhancers, with a large portion showing tissue-specific and developmental stage-specific patterns, pointing to their roles in controlling the ordered spatiotemporal expression of the developmental genes in early human embryos. Moreover, using sequential ChIP-seq, we showed that all three organs have hundreds to thousands of bivalent domains that are marked by both H3K4me3 and H3K27me3, probably to keep the progenitor cells in these organs ready for immediate differentiation into diverse cell types during subsequent developmental processes. Our work illustrates the potentially critical roles of tissue-specific and developmental stage-specific epigenomes in regulating the spatiotemporal expression of developmental genes during early human embryonic development.

  9. Acetaminophen-induced Liver Injury: from Animal Models to Humans.

    PubMed

    Jaeschke, Hartmut; Xie, Yuchao; McGill, Mitchell R

    2014-09-01

    Drug-induced liver injury is an important clinical problem and a challenge for drug development. Whereas progress in understanding rare and unpredictable (idiosyncratic) drug hepatotoxicity is severely hampered by the lack of relevant animal models, enormous insight has been gained in the area of predictable hepatotoxins, in particular acetaminophen-induced liver injury, from a broad range of experimental models. Importantly, mechanisms of toxicity obtained with certain experimental systems, such as in vivo mouse models, primary mouse hepatocytes, and metabolically competent cell lines, are being confirmed in translational studies in patients and in primary human hepatocytes. Despite this progress, suboptimal models are still being used and experimental data can be confusing, leading to controversial conclusions. Therefore, this review attempts to discuss mechanisms of drug hepatotoxicity using the most studied drug acetaminophen as an example. We compare the various experimental models that are used to investigate mechanisms of acetaminophen hepatotoxicity, discuss controversial topics in the mechanisms, and assess how these experimental findings can be translated to the clinic. The success with acetaminophen in demonstrating the clinical relevance of experimental findings could serve as an example for the study of other drug toxicities. PMID:26355817

  10. Morphology and some biomechanical properties of human liver and spleen.

    PubMed

    Stingl, J; Báĉa, V; Cech, P; Kovanda, J; Kovandová, H; Mandys, V; Rejmontová, J; Sosna, B

    2002-12-01

    The aim of the study was an experimental determination of some morphological and mechanical properties of human liver and spleen (amount of collagen in organ capsules, their critical tension and density), followed by a definition of the threshold of critical acceleration, above which the organs can be injured during a car crash. Experiments were done on 33 fresh cadavers (18 males, 15 females; age 3 months to 88 years), and completed by sled tests on dummies testing the loads of both hypochondrial regions protected by air bags and/or seat belts. Results obtained were the following: (1). liver: capsule collagen 14-35%, critical tension 0.066-0.386 MPa, density 0.92-1.19 g/ml, critical acceleration 48-155 g; (2). spleen: capsule collagen 1.8-24.4%, critical tension 0.022-0.652 MPa, density 0.85-1.25 g/ml, critical acceleration 33-149 g. Loads of both hypochondrial regions measured on dummies during a predefined sled test were 34-67 g. Results obtained were evaluated qualitatively and discussed from the point of view of their possible use in future passive safety engineering and design calculations. PMID:12497218

  11. Stereoselective sulphate conjugation of racemic terbutaline by human liver cytosol.

    PubMed

    Walle, T; Walle, U K

    1990-07-01

    1. The enantioselectivity of the sulphation of racemic terbutaline by phenolsulphotransferases was examined in vitro using cytosol from human livers (n = 3) and [35S]-3'-phosphoadenosine-5'-phosphosulphate (PAP35S) as the sulphate donor. 2. The radioactive sulphate conjugate formed was isolated by h.p.l.c. and its enantiomers were separated intact by h.p.l.c. after chiral derivatization. 3. Sulphation of racemic terbutaline occurred with the same apparent Km value for both enantiomers (270 microM). The extent of sulphation of the (+)-enantiomer was double that of the (-)-enantiomer, solely due to a difference in their apparent Vmax values. 4. Sulphation of racemic prenalterol, a structural analogue of terbutaline, also showed a two-fold preference for the (+)-enantiomer. 5. These findings suggest that enantioselective sulphate conjugation of chiral phenolic sympathomimetic amine drugs may lead to enantioselective pharmacokinetics that should be considered in the clinical use of these drugs. PMID:2390423

  12. Chromosome Studies of Virus-infected Semi-continuous Human Embryonic Liver Cells

    PubMed Central

    Zuckerman, A. J.; Taylor, P. E.; Jacobs, J. P.; Jones, C. A.

    1970-01-01

    Semi-continuous human embryonic liver cells infected with San Carlos virus 3 exhibited an increased frequency of chromosomal breaks and other chromosomal abnormalities when compared with uninoculated control cultures. The chromosomes of cells inoculated with AR-17 virus retained their normal structure. The strain of liver cells used in this study is essentially diploid. It represents the first strain of diploid cells so far described from human liver. ImagesFigs. 2-3Fig. 1 PMID:4985032

  13. 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

  14. Steroid metabolism in chimeric mice with humanized liver.

    PubMed

    Lootens, Leen; Van Eenoo, Peter; Meuleman, Philip; Pozo, Oscar J; Van Renterghem, Pieter; Leroux-Roels, Geert; Delbeke, Frans T

    2009-11-01

    Anabolic androgenic steroids are considered to be doping agents and are prohibited in sports. Their metabolism needs to be elucidated to allow for urinary detection by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). Steroid metabolism was assessed using uPA(+/+) SCID mice with humanized livers (chimeric mice). This study presents the results of 19-norandrost-4-ene-3,17-dione (19-norAD) administration to these in vivo mice. As in humans, 19-norandrosterone and 19-noretiocholanolone are the major detectable metabolites of 19-norAD in the urine of chimeric mice.A summary is given of the metabolic pathways found in chimeric mice after administration of three model steroid compounds (methandienone, androst-4-ene-3,17-dione and 19-norandrost-4-ene-3,17-dione). From these studies we can conclude that all major metabolic pathways for anabolic steroids in humans are present in the chimeric mouse. It is hoped that, in future, this promising chimeric mouse model might assist the discovery of new and possible longer detectable metabolites of (designer) steroids. PMID:20355169

  15. Effect of the Human Amniotic Membrane on Liver Regeneration in Rats

    PubMed Central

    Sipahi, Mesut; Şahin, Sevinç; Arslan, Ergin; Börekci, Hasan; Metin, Bayram; Cantürk, Nuh Zafer

    2015-01-01

    Introduction. Operations are performed for broader liver surgery indications for a better understanding of hepatic anatomy/physiology and developments in operation technology. Surgery can cure some patients with liver metastasis of some tumors. Nevertheless, postoperative liver failure is the most feared complication causing mortality in patients who have undergone excision of a large liver mass. The human amniotic membrane has regenerative effects. Thus, we investigated the effects of the human amniotic membrane on regeneration of the resected liver. Methods. Twenty female Wistar albino rats were divided into control and experimental groups and underwent a 70% hepatectomy. The human amniotic membrane was placed over the residual liver in the experimental group. Relative liver weight, histopathological features, and biochemical parameters were assessed on postoperative day 3. Results. Total protein and albumin levels were significantly lower in the experimental group than in the control group. No difference in relative liver weight was observed between the groups. Hepatocyte mitotic count was significantly higher in the experimental group than in the control group. Hepatic steatosis was detected in the experimental group. Conclusion. Applying the amniotic membrane to residual liver adversely affected liver regeneration. However, mesenchymal stem cell research has the potential to accelerate liver regeneration investigations. PMID:26457000

  16. PLASMID DNA DAMAGE CAUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

    EPA Science Inventory

    PLASMID DNA DAMAGE CAOUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

    ABSTRACT

    Both dimethylarsinic acid (DMA(V)) and dimethylarsinous acid (DMA(III)) release iron from human liver ferritin (HLF) with or without the presence of ascorbic acid. ...

  17. PLASMID DNA DAMAGE CAUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

    EPA Science Inventory

    Plasmid DNA damage caused by methylated arsenicals, ascorbic acid and human liver ferritin.

    Arsenic causes cancer in human skin, urinary bladder, lung, liver and kidney and is a significant world-wide public health problem. Although the metabolism of inorganic arsenic is ...

  18. Metabolism of chamaechromone in vitro with human liver microsomes and recombinant human drug-metabolizing enzymes.

    PubMed

    Lou, Yan; Hu, Haihong; Qiu, Yunqing; Zheng, Jinqi; Wang, Linrun; Zhang, Xingguo; Zeng, Su

    2014-04-01

    Chamaechromone is a major component in the dried roots of Stellera chamaejasme with antihepatitis B virus and insecticidal activity. In this study, metabolic profiles of chamaechromone were investigated in human liver microsomes. One monohydroxide and two monoglucuronides of chamaechromone were identified. The enzyme kinetics for both hydroxylation and glucuronidation were fitted to the Michaelis-Menten equation. The hydroxylation of chamaechromone was inhibited by α-naphthoflavone, and predominantly catalyzed by recombinant human cytochrome P450 1A2, whereas the glucuronidation was inhibited by quercetin, 1-naphthol, and fluconazole, and mainly catalyzed by recombinant human UDP-glucuronosyltransferase 1A3, 1A7, 1A9, and 2B7.

  19. Liver.

    PubMed

    Kim, W R; Lake, J R; Smith, J M; Skeans, M A; Schladt, D P; Edwards, E B; Harper, A M; Wainright, J L; Snyder, J J; Israni, A K; Kasiske, B L

    2016-01-01

    The median waiting time for patients with MELD ≥ 35 decreased from 18 days in 2012 to 9 days in 2014, after implementation of the Share 35 policy in June 2013. Similarly, mortality among candidates listed with MELD ≥ 35 decreased from 366 per 100 waitlist years in 2012 to 315 in 2014. The number of new active candidates added to the pediatric liver transplant waiting list in 2014 was 655, down from a peak of 826 in 2005. The number of prevalent candidates (on the list on December 31 of the given year) continued to decline, 401 active and 173 inactive. The number of deceased donor pediatric liver transplants peaked at 542 in 2008 and was 478 in 2014. The number of living donor liver pediatric transplants was 52 in 2014; most were from donors closely related to the recipients. Graft survival continued to improve among pediatric recipients of deceased donor and living donor livers. PMID:26755264

  20. Toward an understanding of the protein interaction network of the human liver

    PubMed Central

    Wang, Jian; Huo, Keke; Ma, Lixin; Tang, Liujun; Li, Dong; Huang, Xiaobi; Yuan, Yanzhi; Li, Chunhua; Wang, Wei; Guan, Wei; Chen, Hui; Jin, Chaozhi; Wei, Junchen; Zhang, Wanqiao; Yang, Yongsheng; Liu, Qiongming; Zhou, Ying; Zhang, Cuili; Wu, Zhihao; Xu, Wangxiang; Zhang, Ying; Liu, Tao; Yu, Donghui; Zhang, Yaping; Chen, Liang; Zhu, Dewu; Zhong, Xing; Kang, Lixin; Gan, Xiang; Yu, Xiaolan; Ma, Qi; Yan, Jing; Zhou, Li; Liu, Zhongyang; Zhu, Yunping; Zhou, Tao; He, Fuchu; Yang, Xiaoming

    2011-01-01

    Proteome-scale protein interaction maps are available for many organisms, ranging from bacteria, yeast, worms and flies to humans. These maps provide substantial new insights into systems biology, disease research and drug discovery. However, only a small fraction of the total number of human protein–protein interactions has been identified. In this study, we map the interactions of an unbiased selection of 5026 human liver expression proteins by yeast two-hybrid technology and establish a human liver protein interaction network (HLPN) composed of 3484 interactions among 2582 proteins. The data set has a validation rate of over 72% as determined by three independent biochemical or cellular assays. The network includes metabolic enzymes and liver-specific, liver-phenotype and liver-disease proteins that are individually critical for the maintenance of liver functions. The liver enriched proteins had significantly different topological properties and increased our understanding of the functional relationships among proteins in a liver-specific manner. Our data represent the first comprehensive description of a HLPN, which could be a valuable tool for understanding the functioning of the protein interaction network of the human liver. PMID:21988832

  1. Photoacoustic physio-chemical analysis of liver conditions in animal and human subjects

    NASA Astrophysics Data System (ADS)

    Wang, Xueding; Xu, Guan; Tian, Chao; Wan, Shanshan; Welling, Theodore H.; Lok, Anna S. F.; Rubin, Jonathan M.

    2016-03-01

    Non-alcoholic fatty liver disease (NAFLD) is a common liver disease affecting 30% of the population in the United States. Biopsy is the gold standard for diagnosing NAFLD. Liver histology assesses the amount of fat, and determines type and extent of cell injury, inflammation and fibrosis. However, liver biopsy is invasive and is limited by sampling error. Current radiological diagnostic modalities can evaluate the 'physical' morphology in liver by quantifying the backscattered US signals, but cannot interrogate the 'histochemical' components forming these backscatterers. For example, ultrasound (US) imaging can detect the presence of fat but cannot differentiate steatosis alone from steatohepatitis. Our previous study of photoacoustic physiochemical analysis (PAPCA) has demonstrated that this method can characterize the histological changes in livers during the progression of NAFLD in animal models. In this study, we will further validate PAPCA with human livers. Ex vivo human liver samples with steatosis, fibrosis and cirrhosis will be scanned using optical illumination at wavelengths of 680-1700 nm and compared to histology results. In vivo study on human subjects with confirmed steatosis is planned using our PA-ultrasound (US) parallel imaging system based on Verasonic US imaging flatform with an L7-4 probe. 10 mJ/cm2 per pulse optical energy at 755 nm will be delivered to the skin surface, which is under the safety limit of American National Standard Institute. Preliminary study with ex vivo human tissue has demonstrated the potential of the proposed approach in differentiating human liver conditions.

  2. Etoxazole is Metabolized Enantioselectively in Liver Microsomes of Rat and Human in Vitro.

    PubMed

    Yao, Zhoulin; Qian, Mingrong; Zhang, Hu; Nie, Jing; Ye, Jingqing; Li, Zuguang

    2016-09-01

    Acaricide etoxazole belongs to the ovicides/miticides diphenyloxazole class, affecting adults to lay sterile eggs by inhibiting chitin biosynthesis possibly. The reverse-phase HPLC-MS/MS method was used to determine the etoxazole enantiomers. The enantioselective degradation behavior of rac-etoxazole in liver microsomes of rat and human in vitro with NADPH was dramatically different. The t1/2 of (R)-etoxazole was 15.23 min in rat liver microsomes and 30.54 min in human liver microsomes, while 21.73 and 23.50 min were obtained for (S)-etoxazole, respectively. The Vmax of (R)-etoxazole was almost 5-fold of (S)-etoxazole in liver microsomes of rat in vitro. However, the Vmax of (S)-etoxazole was almost 2-fold of (R)-etoxazole in liver microsomes of human in vitro. The CLint of etoxazole was also shown the enantioselectivity on the contrary in liver microsomes of rat and human. These results indicated that the metabolism of two etoxazole enantiomers was selective in liver microsomes of rat and human in vitro, and enantioselectivity in the two kinds of liver microsomes was in the difference in degradation performance. The reason might be related to the composition and content involved in the enzyme system. PMID:27479246

  3. Functional human liver preservation and recovery by means of subnormothermic machine perfusion.

    PubMed

    Bruinsma, Bote G; Avruch, James H; Weeder, Pepijn D; Sridharan, Gautham V; Uygun, Basak E; Karimian, Negin G; Porte, Robert J; Markmann, James F; Yeh, Heidi; Uygun, Korkut

    2015-04-27

    There is currently a severe shortage of liver grafts available for transplantation. Novel organ preservation techniques are needed to expand the pool of donor livers. Machine perfusion of donor liver grafts is an alternative to traditional cold storage of livers and holds much promise as a modality to expand the donor organ pool. We have recently described the potential benefit of subnormothermic machine perfusion of human livers. Machine perfused livers showed improving function and restoration of tissue ATP levels. Additionally, machine perfusion of liver grafts at subnormothermic temperatures allows for objective assessment of the functionality and suitability of a liver for transplantation. In these ways a great many livers that were previously discarded due to their suboptimal quality can be rescued via the restorative effects of machine perfusion and utilized for transplantation. Here we describe this technique of subnormothermic machine perfusion in detail. Human liver grafts allocated for research are perfused via the hepatic artery and portal vein with an acellular oxygenated perfusate at 21 °C.

  4. Preserving the morphology and evaluating the quality of liver grafts by hypothermic machine perfusion: a proof-of-concept study using discarded human livers.

    PubMed

    Monbaliu, Diethard; Liu, Qiang; Libbrecht, Louis; De Vos, Rita; Vekemans, Katrien; Debbaut, Charlotte; Detry, Olivier; Roskams, Tania; van Pelt, Jos; Pirenne, Jacques

    2012-12-01

    The wider use of livers from expanded criteria donors and donation after circulatory death donors may help to improve access to liver transplantation. A prerequisite for safely using these higher risk livers is the development of objective criteria for assessing their condition before transplantation. Compared to simple cold storage, hypothermic machine perfusion (HMP) provides a unique window for evaluating liver grafts between procurement and transplantation. In this proof-of-concept study, we tested basic parameters during HMP that may reflect the condition of human liver grafts, and we assessed their morphology after prolonged HMP. Seventeen discarded human livers were machine-perfused. Eleven livers were nontransplantable (major absolute contraindications and severe macrovesicular steatosis in the majority of the cases). Six livers were found in retrospect to be transplantable but could not be allocated and served as controls. Metabolic parameters (pH, lactate, partial pressure of oxygen, and partial pressure of carbon dioxide), enzyme release in the perfusate [aspartate aminotransferase (AST) and lactate dehydrogenase (LDH)], and arterial/portal resistances were monitored during HMP. Nontransplantable livers released more AST and LDH than transplantable livers. In contrast, arterial/portal vascular resistances and metabolic profiles did not differ between the 2 groups. Morphologically, transplantable livers remained well preserved after 24 hours of HMP. In conclusion, HMP preserves the morphology of human livers for prolonged periods. A biochemical analysis of the perfusate provides information reflecting the extent of the injury endured.

  5. Role of Chymase in the Development of Liver Cirrhosis and Its Complications: Experimental and Human Data

    PubMed Central

    Sansoè, Giovanni; Aragno, Manuela; Mastrocola, Raffaella; Mengozzi, Giulio; Novo, Erica; Parola, Maurizio

    2016-01-01

    Background Tissue Angiotensin II (Ang-II), produced through local non ACE-dependent pathways, stimulates liver fibrogenesis, renal vasoconstriction and sodium retention. Aim To highlight chymase-dependent pathway of Ang-II production in liver and kidney during cirrhosis development. Methods Liver histology, portal pressure, liver and kidney function, and hormonal status were investigated in rat liver cirrhosis induced through 13 weeks of CCl4, with or without chymase inhibitor SF2809E, administered between 4th and 13th CCl4 weeks; liver and kidney chymase immunolocation and Ang-II content were assessed. Chymase immunohistochemistry was also assessed in normal and cirrhotic human liver, and chymase mRNA transcripts were measured in human HepG2 cells and activated hepatic stellate cells (HSC/MFs) in vitro. Results Rats receiving both CCl4 and SF2809E showed liver fibrotic septa focally linking portal tracts but no cirrhosis, as compared to ascitic cirrhotic rats receiving CCl4. SF2809E reduced portal pressure, plasma bilirubin, tissue content of Ang-II, plasma renin activity, norepinephrine and vasopressin, and increased glomerular filtration rate, water clearance, urinary sodium excretion. Chymase tissue content was increased and detected in α-SMA-positive liver myofibroblasts and in kidney tubular cells of cirrhotic rats. In human cirrhosis, chymase was located in hepatocytes of regenerative nodules. Human HepG2 cells and HSC/MFs responded to TGF-β1 by up-regulating chymase mRNA transcription. Conclusions Chymase, through synthesis of Ang-II and other mediators, plays a role in the derangement of liver and kidney function in chronic liver diseases. In human cirrhosis, chymase is well-represented and apt to become a future target of pharmacological treatment. PMID:27637026

  6. Bile salt recognition by human liver fatty acid binding protein.

    PubMed

    Favretto, Filippo; Santambrogio, Carlo; D'Onofrio, Mariapina; Molinari, Henriette; Grandori, Rita; Assfalg, Michael

    2015-04-01

    Fatty acid binding proteins (FABPs) act as intracellular carriers of lipid molecules, and play a role in global metabolism regulation. Liver FABP (L-FABP) is prominent among FABPs for its wide ligand repertoire, which includes long-chain fatty acids as well as bile acids (BAs). In this work, we performed a detailed molecular- and atomic-level analysis of the interactions established by human L-FABP with nine BAs to understand the binding specificity for this important class of cholesterol-derived metabolites. Protein-ligand complex formation was monitored using heteronuclear NMR, steady-state fluorescence spectroscopy, and mass spectrometry. BAs were found to interact with L-FABP with dissociation constants in the narrow range of 0.6-7 μm; however, the diverse substitution patterns of the sterol nucleus and the presence of side-chain conjugation resulted in complexes endowed with various degrees of conformational heterogeneity. Trihydroxylated BAs formed monomeric complexes in which single ligand molecules occupied similar internal binding sites, based on chemical-shift perturbation data. Analysis of NMR line shapes upon progressive addition of taurocholate indicated that the binding mechanism departed from a simple binary association equilibrium, and instead involved intermediates along the binding path. The co-linear chemical shift behavior observed for L-FABP complexes with cholate derivatives added insight into conformational dynamics in the presence of ligands. The observed spectroscopic features of L-FABP/BA complexes, discussed in relation to ligand chemistry, suggest possible molecular determinants of recognition, with implications regarding intracellular BA transport. Our findings suggest that human L-FABP is a poorly selective, universal BA binder. PMID:25639618

  7. Bile salt recognition by human liver fatty acid binding protein.

    PubMed

    Favretto, Filippo; Santambrogio, Carlo; D'Onofrio, Mariapina; Molinari, Henriette; Grandori, Rita; Assfalg, Michael

    2015-04-01

    Fatty acid binding proteins (FABPs) act as intracellular carriers of lipid molecules, and play a role in global metabolism regulation. Liver FABP (L-FABP) is prominent among FABPs for its wide ligand repertoire, which includes long-chain fatty acids as well as bile acids (BAs). In this work, we performed a detailed molecular- and atomic-level analysis of the interactions established by human L-FABP with nine BAs to understand the binding specificity for this important class of cholesterol-derived metabolites. Protein-ligand complex formation was monitored using heteronuclear NMR, steady-state fluorescence spectroscopy, and mass spectrometry. BAs were found to interact with L-FABP with dissociation constants in the narrow range of 0.6-7 μm; however, the diverse substitution patterns of the sterol nucleus and the presence of side-chain conjugation resulted in complexes endowed with various degrees of conformational heterogeneity. Trihydroxylated BAs formed monomeric complexes in which single ligand molecules occupied similar internal binding sites, based on chemical-shift perturbation data. Analysis of NMR line shapes upon progressive addition of taurocholate indicated that the binding mechanism departed from a simple binary association equilibrium, and instead involved intermediates along the binding path. The co-linear chemical shift behavior observed for L-FABP complexes with cholate derivatives added insight into conformational dynamics in the presence of ligands. The observed spectroscopic features of L-FABP/BA complexes, discussed in relation to ligand chemistry, suggest possible molecular determinants of recognition, with implications regarding intracellular BA transport. Our findings suggest that human L-FABP is a poorly selective, universal BA binder.

  8. Expression kinetics of hepatic progenitor markers in cellular models of human liver development recapitulating hepatocyte and biliary cell fate commitment.

    PubMed

    Chaudhari, Pooja; Tian, Lipeng; Deshmukh, Abhijeet; Jang, Yoon-Young

    2016-09-01

    Due to the limitations of research using human embryos and the lack of a biological model of human liver development, the roles of the various markers associated with liver stem or progenitor cell potential in humans are largely speculative, and based on studies utilizing animal models and certain patient tissues. Human pluripotent stem cell-based in vitro multistage hepatic differentiation systems may serve as good surrogate models for mimicking normal human liver development, pathogenesis and injury/regeneration studies. Here, we describe the implications of various liver stem or progenitor cell markers and their bipotency (i.e. hepatocytic- and biliary-epithelial cell differentiation), based on the pluripotent stem cell-derived model of human liver development. Future studies using the human cellular model(s) of liver and biliary development will provide more human relevant biological and/or pathological roles of distinct markers expressed in heterogeneous liver stem/progenitor cell populations.

  9. Decision support tool for soil sampling of heterogeneous pesticide (chlordecone) pollution.

    PubMed

    Clostre, Florence; Lesueur-Jannoyer, Magalie; Achard, Raphaël; Letourmy, Philippe; Cabidoche, Yves-Marie; Cattan, Philippe

    2014-02-01

    When field pollution is heterogeneous due to localized pesticide application, as is the case of chlordecone (CLD), the mean level of pollution is difficult to assess. Our objective was to design a decision support tool to optimize soil sampling. We analyzed the CLD heterogeneity of soil content at 0-30- and 30-60-cm depth. This was done within and between nine plots (0.4 to 1.8 ha) on andosol and ferralsol. We determined that 20 pooled subsamples per plot were a satisfactory compromise with respect to both cost and accuracy. Globally, CLD content was greater for andosols and the upper soil horizon (0-30 cm). Soil organic carbon cannot account for CLD intra-field variability. Cropping systems and tillage practices influence the CLD content and distribution; that is CLD pollution was higher under intensive banana cropping systems and, while upper soil horizon was more polluted than the lower one with shallow tillage (<40 cm), deeper tillage led to a homogenization and a dilution of the pollution in the soil profile. The decision tool we proposed compiles and organizes these results to better assess CLD soil pollution in terms of sampling depth, distance, and unit at field scale. It accounts for sampling objectives, farming practices (cropping system, tillage), type of soil, and topographical characteristics (slope) to design a relevant sampling plan. This decision support tool is also adaptable to other types of heterogeneous agricultural pollution at field level.

  10. Effects of chlordecone on 20-hydroxyecdysone concentration and chitobiase activity in a decapod crustacean, Macrobrachium rosenbergii.

    PubMed

    Lafontaine, Anne; Gismondi, Eric; Boulangé-Lecomte, Céline; Geraudie, Perrine; Dodet, Nathalie; Caupos, Fanny; Lemoine, Soazig; Lagadic, Laurent; Thomé, Jean-Pierre; Forget-Leray, Joëlle

    2016-07-01

    Chlordecone (CLD) is an organochlorine insecticide abundant in aquatic environment of the French West Indies. However, few studies have investigated its impact on freshwater invertebrates. Whereas CLD is suspected of inducing endocrine disruption, this work aimed to study the effects of environmentally relevant concentrations of CLD on the 20-hydroxyecdysone (20-HE) hormone concentration and on the chitobiase activity, both having key roles in the molting process of crustaceans. In addition, the bioaccumulation of CLD was measured in the muscle tissue of Macrobrachium rosenbergii to underline potential dose-response relationship. The results have shown that CLD was bioaccumulated in exposed organisms according to a trend to a dose-response relationship. Moreover, it was observed that CLD decreased the 20-HE concentration in exposed prawns when compared to control, whatever the duration of exposure, as well as it inhibited the chitobiase activity after 30days of exposure. The present study indicates that CLD could interfere with molting process of M. rosenbergii by disturbing the 20-HE concentration and the activity of chitobiase, suggesting consequences at the long term on the shrimp development. This study also confirmed that CLD could be an endocrine disruptor in decapod crustaceans, as it was already observed in vertebrates.

  11. Effects of chlordecone on 20-hydroxyecdysone concentration and chitobiase activity in a decapod crustacean, Macrobrachium rosenbergii.

    PubMed

    Lafontaine, Anne; Gismondi, Eric; Boulangé-Lecomte, Céline; Geraudie, Perrine; Dodet, Nathalie; Caupos, Fanny; Lemoine, Soazig; Lagadic, Laurent; Thomé, Jean-Pierre; Forget-Leray, Joëlle

    2016-07-01

    Chlordecone (CLD) is an organochlorine insecticide abundant in aquatic environment of the French West Indies. However, few studies have investigated its impact on freshwater invertebrates. Whereas CLD is suspected of inducing endocrine disruption, this work aimed to study the effects of environmentally relevant concentrations of CLD on the 20-hydroxyecdysone (20-HE) hormone concentration and on the chitobiase activity, both having key roles in the molting process of crustaceans. In addition, the bioaccumulation of CLD was measured in the muscle tissue of Macrobrachium rosenbergii to underline potential dose-response relationship. The results have shown that CLD was bioaccumulated in exposed organisms according to a trend to a dose-response relationship. Moreover, it was observed that CLD decreased the 20-HE concentration in exposed prawns when compared to control, whatever the duration of exposure, as well as it inhibited the chitobiase activity after 30days of exposure. The present study indicates that CLD could interfere with molting process of M. rosenbergii by disturbing the 20-HE concentration and the activity of chitobiase, suggesting consequences at the long term on the shrimp development. This study also confirmed that CLD could be an endocrine disruptor in decapod crustaceans, as it was already observed in vertebrates. PMID:27108204

  12. Volumetric Growth of the Liver in the Human Fetus: An Anatomical, Hydrostatic, and Statistical Study

    PubMed Central

    Szpinda, Michał; Paruszewska-Achtel, Monika; Woźniak, Alina; Mila-Kierzenkowska, Celestyna; Elminowska-Wenda, Gabriela; Dombek, Małgorzata; Szpinda, Anna; Badura, Mateusz

    2015-01-01

    Using anatomical, hydrostatic, and statistical methods, liver volumes were assessed in 69 human fetuses of both sexes aged 18–30 weeks. No sex differences were found. The median of liver volume achieved by hydrostatic measurements increased from 6.57 cm3 at 18–21 weeks through 14.36 cm3 at 22–25 weeks to 20.77 cm3 at 26–30 weeks, according to the following regression: y = −26.95 + 1.74 × age ± Z  × (−3.15 + 0.27 × age). The median of liver volume calculated indirectly according to the formula liver volume = 0.55 × liver length × liver transverse diameter × liver sagittal diameter increased from 12.41 cm3 at 18–21 weeks through 28.21 cm3 at 22–25 weeks to 49.69 cm3 at 26–30 weeks. There was a strong relationship (r = 0.91, p < 0.001) between the liver volumes achieved by hydrostatic (x) and indirect (y) methods, expressed by y = −0.05 + 2.16x  ± 7.26. The liver volume should be calculated as follows liver volume = 0.26 × liver length × liver transverse diameter × liver sagittal diameter. The age-specific liver volumes are of great relevance in the evaluation of the normal hepatic growth and the early diagnosis of fetal micro- and macrosomias. PMID:26413551

  13. Differential gene expression of the three natriuretic peptides and natriuretic peptide receptor subtypes in human liver.

    PubMed Central

    Vollmar, A M; Paumgartner, G; Gerbes, A L

    1997-01-01

    BACKGROUND: Various effects of atrial natriuretic peptide (ANP) on the liver have been observed. However, there is limited information about the types of receptors for natriuretic peptides expressed by the human liver. AIM: To investigate gene expression of the three NP receptor types (NPR) as well as of the NP in human liver. METHODS: Presence of mRNA coding for all three NPR and for ANP, brain and C-type natriuretic peptide (BNP, CNP) was investigated by reverse transcription-polymerase chain reaction (RT-PCR). Human liver tissues and hepatocellular carcinoma tissues were examined. RESULTS: Specific PCR products for all three NPR, namely NPR-A, B, and C, could be detected. Moreover, ANP and CNP, but not BNP mRNA was detectable. The concentration of ANP transcripts was up to fivefold higher in hepatocellular carcinoma compared with non-tumorous liver tissue of the same subjects. No difference in the expression of NP receptors relative to GAPDH mRNA of tumorous and non-tumorous tissue was observed except of slightly increased NPR-A transcripts. CONCLUSION: These data show that NPR transcripts are coexpressed with ANP and CNP mRNA in the human liver. This provides evidence for a local NP system in the human liver. Images PMID:9155593

  14. Xeno-repopulation of Fah -/- Nod/Scid mice livers by human hepatocytes.

    PubMed

    Su, Baoliang; Liu, Changcheng; Xiang, Dao; Zhang, Haibin; Yuan, Siming; Wang, Minjun; Chen, Fei; Zhu, Haiying; He, Zhiying; Wang, Xin; Hu, Yiping

    2011-03-01

    Functional human hepatocytes xenografted into the liver of mice can be used as a model system to study pharmacokinetics, infection of hepatitis viruses, and the efficacy of hepatitis vaccines. Significant levels of liver xeno-repopulation have been reported in Fah (-/-) Rag2 (-/-) Il2rg (-/-) mice. However, A new model, termed Fah (-/-) Nod/Scid mice, which combines the advantages of liver repopulation in Fah (-/-) mice with the ease of xenotransplantation in Nod/Scid mice was obtained by gradual cross-breeding. Fah (-/-) Nod/Scid mice were easily maintained in breeding colonies and in adult animal care facilities. FK506 treatment combined with gradual withdrawal of NTBC before cell transplantation ensured that Fah (-/-) Nod/Scid mice were susceptible to liver xeno-repopulation by human hepatocytes; the proportion of engrafted human hepatocytes reached 33.6%. The function of the expanded human hepatocytes within the chimeric liver was confirmed by weight curve analysis, the expression of characteristic proteins, and the biochemical analysis of liver function. These results show that Fah (-/-) Nod/Scid mice are an ideal humanized liver mouse model with many useful applications.

  15. Blocking porcine sialoadhesin improves extracorporeal porcine liver xenoperfusion with human blood

    PubMed Central

    Waldman, Joshua P.; Vogel, Thomas; Burlak, Christopher; Coussios, Constantin; Dominguez, Javier; Friend, Peter; Rees, Michael A.

    2013-01-01

    Patients in fulminant hepatic failure currently do not have a temporary means of support while awaiting liver transplantation. A potential therapeutic approach for such patients is the use of extracorporeal perfusion with porcine livers as a form of “liver dialysis”. During a 72-hour extracorporeal perfusion of porcine livers with human blood, porcine Kupffer cells bind to and phagocytose human red blood cells (hRBC) causing the hematocrit to decrease to 2.5% of the original value. Our laboratory has identified porcine sialoadhesin expressed on Kupffer cells as the lectin responsible for binding N-acetylneuraminic acid on the surface of the hRBC. We evaluated whether blocking porcine sialoadhesin prevents the recognition and subsequent destruction of hRBCs seen during extracorporeal porcine liver xenoperfusion. Ex vivo studies were performed using wild type pig livers perfused with isolated hRBCs for 72-hours in the presence of an anti-porcine sialoadhesin antibody or isotype control. The addition of an anti-porcine sialoadhesin antibody to an extracorporeal porcine liver xenoperfusion model reduces the loss of hRBC over a 72 hour period. Sustained liver function was demonstrated throughout the perfusion. This study illustrates the role of sialoadhesin in mediating the destruction of hRBCs in an extracorporeal porcine liver xenoperfusion model. PMID:23822217

  16. Human liver glucuronate 2-sulphatase. Purification, characterization and catalytic properties.

    PubMed Central

    Freeman, C; Hopwood, J J

    1989-01-01

    Human glucuronate 2-sulphatase (GAS), which is involved in the degradation of the glycosaminoglycans heparan sulphate and chondroitin 6-sulphate, was purified almost 2,000,000-fold to homogeneity in 8% yield from liver with a four-step six-column procedure, which consists of a concanavalin A-Sepharose/Blue A-agarose coupled step, a DEAE-Sephacel/octyl-Sepharose coupled step, CM-Sepharose chromatography and gel-permeation chromatography. Although more than 90% of GAS activity had a pI of greater than 7.5, other forms with pI values of 5.8, 5.3, 4.7 and less than 4.0 were also present. The pI greater than 7.5 form of GAS had a native molecular mass of 63 kDa. SDS/polyacrylamide-gel-electrophoretic analysis resulted in two polypeptide subunits of molecular mass 47 and 19.5 kDa. GAS was active towards disaccharide substrates derived from heparin [O-(beta-glucuronic acid 2-sulphate)-(1----4)-O-(2,5)-anhydro[1-3H]mannitol 6-sulphate (GSMS)] and chondroitin 6-sulphate [O-(beta-glucuronic acid 2-sulphate-(1----3)-O-(2,5)-anhydro[1-3H]talitol 6-sulphate (GSTS)]. GAS activity towards GSMS and GSTS was at pH optima of 3.2 and 3.0 respectively with apparent Km values of 0.3 and 0.6 microM respectively and corresponding Vmax values of 12.8 and 13.7 mumol/min per mg of protein respectively. Sulphate and phosphate ions are potent inhibitors of enzyme activity. Cu2+ ions stimulated, whereas EDTA inhibited enzyme activity. It was concluded that GAS is required together with a series of other exoenzyme activities in the lysosomal degradation of glycosaminoglycans containing glucuronic acid 2-sulphate residues. Images Fig. 5. PMID:2497731

  17. Substrate specificity of human liver neutral alpha-mannosidase.

    PubMed Central

    al Daher, S; De Gasperi, R; Daniel, P; Hirani, S; Warren, C; Winchester, B

    1992-01-01

    The digestion of radiolabelled natural oligosaccharide substrates by human liver neutral alpha-mannosidase has been studied by h.p.l.c. and h.p.t.l.c. The high-mannose oligosaccharides Man9GlcNAc and Man8GlcNAc are hydrolysed by the enzyme by two distinct non-random routes to a common product of composition Man6GlcNAc, which is then slowly converted into a unique Man5GlcNAc oligosaccharide, Man alpha(1----2)Man alpha(1----2)Man alpha(1----3)[Man alpha (1----6)] Man beta(1----4)GlcNAc. These pathways are different from the processing and lysosomal catabolic pathways for these structures. In particular, the alpha(1----2)-linked mannose residues attached to the core alpha(1----3)-linked mannose residue are resistant to hydrolysis. The key processing intermediate, Man alpha(1----3)[Man alpha(1----6)]Man alpha(1----6)[Man alpha(1----3)] Man beta(1----4)GlcNAc, is not produced in the digestion of high-mannose glycans by the neutral alpha-mannosidase, but it is hydrolysed by the enzyme by a non-random route to Man beta(1----4)GlcNAc via the core structure Man alpha(1----3)[Man alpha(1----6)]Man beta(1----4)GlcNAc. In contrast with its ready hydrolysis by lysosomal alpha-mannosidase, the core alpha(1----3)-mannosidic linkage is quite resistant to hydrolysis by neutral alpha-mannosidase. The precise specificity of neutral alpha-mannosidase towards high-mannose oligosaccharides suggests that it has a role in the modification of such structures in the cytosol. Images Fig. 4. PMID:1520283

  18. Ontogeny, distribution and potential roles of 5-hydroxymethylcytosine in human liver function

    PubMed Central

    2013-01-01

    Background Interindividual differences in liver functions such as protein synthesis, lipid and carbohydrate metabolism and drug metabolism are influenced by epigenetic factors. The role of the epigenetic machinery in such processes has, however, been barely investigated. 5-hydroxymethylcytosine (5hmC) is a recently re-discovered epigenetic DNA modification that plays an important role in the control of gene expression. Results In this study, we investigate 5hmC occurrence and genomic distribution in 8 fetal and 7 adult human liver samples in relation to ontogeny and function. LC-MS analysis shows that in the adult liver samples 5hmC comprises up to 1% of the total cytosine content, whereas in all fetal livers it is below 0.125%. Immunohistostaining of liver sections with a polyclonal anti-5hmC antibody shows that 5hmC is detected in most of the hepatocytes. Genome-wide mapping of the distribution of 5hmC in human liver samples by next-generation sequencing shows significant differences between fetal and adult livers. In adult livers, 5hmC occupancy is overrepresented in genes involved in active catabolic and metabolic processes, whereas 5hmC elements which are found in genes exclusively in fetal livers and disappear in the adult state, are more specific to pathways for differentiation and development. Conclusions Our findings suggest that 5-hydroxymethylcytosine plays an important role in the development and function of the human liver and might be an important determinant for development of liver diseases as well as of the interindividual differences in drug metabolism and toxicity. PMID:23958281

  19. Novel Management of Acute or Secondary Biliary Liver Conditions Using Hepatically Differentiated Human Dental Pulp Cells

    PubMed Central

    Ishkitiev, Nikolay; Imai, Toshio; Tanaka, Tomoko; Fushimi, Naho; Mitev, Vanyo; Okada, Mio; Tominaga, Noriko; Ono, Sachie; Ishikawa, Hiroshi

    2015-01-01

    The current definitive treatment for acute or chronic liver condition, that is, cirrhosis, is liver transplantation from a limited number of donors, which might cause complications after donation. Hence, bone marrow stem cell transplantation has been developed, but the risk of carcinogenesis remains. We have recently developed a protocol for hepatic differentiation of CD117+ stem cells from human exfoliated deciduous teeth (SHED). In the present study, we examine whether SHED hepatically differentiated (hd) in vitro could be used to treat acute liver injury (ALI) and secondary biliary cirrhosis. The CD117+ cell fraction was magnetically separated from SHED and then differentiated into hepatocyte-like cells in vitro. The cells were transplanted into rats with either ALI or induced secondary biliary cirrhosis. Engraftment of human liver cells was determined immunohistochemically and by in situ hybridization. Recovery of liver function was examined by means of histochemical and serological tests. Livers of transplanted animals were strongly positive for human immunohistochemical factors, and in situ hybridization confirmed engraftment of human hepatocytes. The tests for recovery of liver function confirmed the presence of human hepatic markers in the animals' blood serum and lack of fibrosis and functional integration of transplanted human cells into livers. No evidence of malignancy was found. We show that in vitro hdSHED engraft morphologically and functionally into the livers of rats having acute injury or secondary biliary cirrhosis. SHED are readily accessible adult stem cells, capable of proliferating in large numbers before differentiating in vitro. This makes SHED an appropriate and safe stem cell source for regenerative medicine. PMID:25234861

  20. 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.

  1. Identification of human liver microsomal proteins adducted by a reactive metabolite using shotgun proteomics.

    PubMed

    Yang, Yanou; Xiao, Qing; Humphreys, W Griffith; Dongre, Ashok; Shu, Yue-Zhong

    2014-09-15

    Covalent modification of cellular proteins by chemically reactive compounds/metabolites has the potential to disrupt biological function and elicit serious adverse drug reactions. Information on the nature and binding patterns of protein targets are critical toward understanding the mechanism of drug induced toxicity. Protein covalent binding studies established in liver microsomes can quantitively estimate the extent of protein modification, but they provide little information on the nature of the modified proteins. In this article, we describe a label-free shotgun proteomic workflow for the identification of target proteins modified in situ by reactive metabolites in human liver microsome incubations. First, we developed a shotgun proteomic workflow for the characterization of the human liver microsomal subproteome, which consists of predominately membrane-bound proteins. Human liver microsomes were solubilized with a combination of MS-compatible organic solvents followed by protein reduction, alkylation, and tryptic digestion. The unmodified samples were analyzed by UHPLC-MS/MS, and the proteins were identified by database searching. This workflow led to the successful identification of 329 human liver microsomal subproteome proteins with 1% FDR (false discovery rate). The same method was then applied to identify the modifications of human liver microsomal proteins by a known reactive metabolite 2-(methylsulfonyl)benzo[d]thiazole (2), either after incubation directly with 2 or with its parent compound 2-(methylthio)benzo[d]thiazole (1). A total of 19 modified constituent peptides which could be mapped to 18 proteins were identified in human liver microsomes incubated directly with 2. Among these, 5 modified constituent peptides which could be mapped to 4 proteins were identified in incubation with 1, which is known to generate 2 in human liver microsomal incubations. This label-free workflow is generally applicable to the identification and characterization of

  2. Detection of cytomegalovirus and human herpesvirus-6 DNA in liver biopsy specimens and their correlation with rejection after liver transplantation.

    PubMed

    Guardia-Silva, A C; Stucchi, R S B; Sampaio, A M; Milan, A; Costa, S C B; Boin, I F S F

    2012-10-01

    Cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6) reactivation after transplantation put patients at an increased risk of graft rejection mainly among those who receive organs that are positive in their donor biopsies. The aim of this study was to investigate the presence of CMV and HHV-6 DNA in liver biopsy specimens from the donors and from their grafts for correlation with rejection after transplantation. We followed 41 liver transplantation patients whose samples were evaluated using nested-polymerase chain reactions (N-PCR). Twenty-one (51%) of the 41 studied patients experienced rejection; 4/21 (19%) were CMV positive in the donor biopsy specimens and remained positive; another 5 subjects became positive. The patients who received organs from donors with biopsies positive for CMV demonstrated a trend to develop graft rejection after transplantation (Fisher's exact test [P = .0591] with significant results on univariate and multivariate analysis [P = .042]). Eight of the 21 who experienced rejection episodes were HHV-6 positive in the donor biopsy but there was no statistical significance CMV DNA diagnosed in liver donor biopsies remained positive posttransplantation in liver biopsy recipients; it was considered a tendency to develop acute cellular rejection after transplantation.

  3. Comparison of human hepatocytes isolated from livers accepted or discarded for orthotopic transplantation.

    PubMed

    Groothuis, G M; Sandker, G W; Pruim, J; Weert, B; Slooff, M J; Meijer, D K

    1995-12-01

    The aim of this study was to compare human hepatocytes isolated from livers accepted and from livers discarded for transplantation with respect to viability and drug transport function. In addition, the influence of age of the donor and preservation time of the liver on cell viability was determined. Cell viability was assessed by trypan blue exclusion, MTT reduction, morphological integrity and ATP content, and drug transport function by uptake and excretion of taurocholic acid. Hepatocytes could be isolated successfully from livers accepted as well as from livers discarded for transplantation, with a median yield of 5.0 x 10(6) cells/g (range 0.1 to 42.4) and 0.7 x 10(6) cells/g (range 0.0 to 22.7), respectively (not significantly different). These cells were not significantly different with respect to viability and transport rate of taurocholate. Neither the age of the donor nor the duration of liver preservation (6-43 hr in University of Wisconsin solution) significantly influenced cell yield and viability. It is concluded that because of this overlap in cell viability, hepatocytes isolated both from accepted and from discarded livers can in principle be used to investigate drug transport functions in the human liver. PMID:20650173

  4. Human Hepatic Stem Cell and Maturational Liver Lineage Biology

    PubMed Central

    Turner, Rachael; Lozoya, Oswaldo; Wang, Yunfang; Cardinale, Vincenzo; Gaudio, Eugenio; Alpini, Gianfranco; Mendel, Gemma; Wauthier, Eliane; Barbier, Claire; Alvaro, Domenico; Reid, Lola M.

    2011-01-01

    Livers are comprised of maturational lineages of cells beginning extrahepatically in the hepato-pancreatic common duct near the duodenum and intrahepatically in zone 1 by the portal triads. The extrahepatic stem cell niches are the peribiliary glands deep within the walls of the bile ducts; those intrahepatically are the canals of Hering in postnatal livers and that derive from ductal plates in fetal livers. Intrahepatically, there are at least 8 maturational lineage stages from the stem cells in zone 1 (periportal), through the midacinar region (zone 2), to the most mature cells and apoptotic cells found pericentrally in zone 3. Those found in the biliary tree are still being defined. Parenchymal cells are closely associated with lineages of mesenchymal cells, and their maturation is coordinated. Each lineage stage consists of parenchymal and mesenchymal cell partners distinguishable by their morphology, ploidy, antigens, biochemical traits, gene expression, and ability to divide. They are governed by changes in chromatin (e.g. methylation), gradients of paracrine signals (soluble factors and insoluble extracellular matrix components), mechanical forces, and feedback loop signals derived from late lineage cells. Feedback loop signals, secreted by late lineage stage cells into bile, flow back to the periportal area and regulate the stem cells and other early lineage stage cells, in mechanisms dictating the size of the liver mass. Recognition of maturational lineage biology and its regulation by these multiple mechanisms offers new understandings of liver biology, pathologies, and strategies for regenerative medicine. PMID:21374667

  5. Reduction of 7-ketolithocholic acid by human liver enzyme preparations in vitro.

    PubMed

    Amuro, Y; Yamade, W; Kudo, K; Yamamoto, T; Hada, T; Higashino, K

    1989-01-01

    The formation of chenodeoxycholic and ursodeoxycholic acids from 7-ketolithocholic acid by human liver preparations was examined in vitro. Liver preparations were incubated with 7-ketolithocholic acid at pH 5.5 in a sodium-potassium-phosphate buffer containing NADPH or NADH. The products formed were analyzed by gas chromatography and gas chromatography-mass spectrometry. Results showed that chenodeoxycholic and ursodeoxycholic acids could be formed from 7-ketolithocholic acid by human liver enzyme(s). The enzyme(s) required NADPH but not NADH as coenzyme and was localized largely in the microsomes. The conjugated 7-ketolithocholic acid, especially the taurine conjugated, was predominantly reduced to chenodeoxycholic acid, whereas the unconjugated 7-ketolithocholic acid was not reduced well to either chenodeoxycholic acid or ursodeoxycholic acid. Thus the reduction of 7-ketolithocholic acid by human liver enzyme(s) was found to be dependent on whether the substrate was conjugated or not. PMID:2912152

  6. Decreased hepatotoxic bile acid composition and altered synthesis in progressive human nonalcoholic fatty liver disease

    SciTech Connect

    Lake, April D.; Novak, Petr; Shipkova, Petia; Aranibar, Nelly; Robertson, Donald; Reily, Michael D.; Lu, Zhenqiang; Lehman-McKeeman, Lois D.; Cherrington, Nathan J.

    2013-04-15

    Bile acids (BAs) have many physiological roles and exhibit both toxic and protective influences within the liver. Alterations in the BA profile may be the result of disease induced liver injury. Nonalcoholic fatty liver disease (NAFLD) is a prevalent form of chronic liver disease characterized by the pathophysiological progression from simple steatosis to nonalcoholic steatohepatitis (NASH). The hypothesis of this study is that the ‘classical’ (neutral) and ‘alternative’ (acidic) BA synthesis pathways are altered together with hepatic BA composition during progression of human NAFLD. This study employed the use of transcriptomic and metabolomic assays to study the hepatic toxicologic BA profile in progressive human NAFLD. Individual human liver samples diagnosed as normal, steatosis, and NASH were utilized in the assays. The transcriptomic analysis of 70 BA genes revealed an enrichment of downregulated BA metabolism and transcription factor/receptor genes in livers diagnosed as NASH. Increased mRNA expression of BAAT and CYP7B1 was observed in contrast to decreased CYP8B1 expression in NASH samples. The BA metabolomic profile of NASH livers exhibited an increase in taurine together with elevated levels of conjugated BA species, taurocholic acid (TCA) and taurodeoxycholic acid (TDCA). Conversely, cholic acid (CA) and glycodeoxycholic acid (GDCA) were decreased in NASH liver. These findings reveal a potential shift toward the alternative pathway of BA synthesis during NASH, mediated by increased mRNA and protein expression of CYP7B1. Overall, the transcriptomic changes of BA synthesis pathway enzymes together with altered hepatic BA composition signify an attempt by the liver to reduce hepatotoxicity during disease progression to NASH. - Highlights: ► Altered hepatic bile acid composition is observed in progressive NAFLD. ► Bile acid synthesis enzymes are transcriptionally altered in NASH livers. ► Increased levels of taurine and conjugated bile acids

  7. Metabolism of ethylbenzene by human liver microsomes and recombinant human cytochrome P450s (CYP).

    PubMed

    Sams, Craig; Loizou, George D; Cocker, John; Lennard, Martin S

    2004-03-01

    The enzyme kinetics of the initial hydroxylation of ethylbenzene to form 1-phenylethanol were determined in human liver microsomes. The individual cytochrome P450 (CYP) forms catalysing this reaction were identified using selective inhibitors and recombinant preparations of hepatic CYPs. Production of 1-phenylethanol in hepatic microsomes exhibited biphasic kinetics with a high affinity, low Km, component (mean Km = 8 microM; V(max) = 689 pmol/min/mg protein; n = 6 livers) and a low affinity, high Km, component (Km = 391 microM; V(max) = 3039 pmol/min/mg protein; n = 6). The high-affinity component was inhibited 79%-95% (mean 86%) by diethyldithiocarbamate, and recombinant CYP2E1 was shown to metabolise ethylbenzene with low Km (35 microM), but also low (max) (7 pmol/min/pmol P450), indicating that this isoform catalysed the high-affinity component. Recombinant CYP1A2 and CYP2B6 exhibited high V(max) (88 and 71 pmol/min/pmol P450, respectively) and high Km (502 and 219 microM, respectively), suggesting their involvement in catalysing the low-affinity component. This study has demonstrated that CYP2E1 is the major enzyme responsible for high-affinity side chain hydroxylation of ethylbenzene in human liver microsomes. Activity of this enzyme in the population is highly variable due to induction or inhibition by physiological factors, chemicals in the diet or some pharmaceuticals. This variability can be incorporated into the risk assessment process to improve the setting of occupational exposure limits and guidance values for biological monitoring.

  8. Expression, purification and bioactivity of human augmenter of liver regeneration

    PubMed Central

    Zhang, Yang-De; Zhou, Jian; Zhao, Jin-Feng; Peng, Jian; Liu, Xiao-Dong; Liu, Xin-Sheng; Jia, Ze-Ming

    2006-01-01

    AIM: To construct the expression vectors for prokaryotic and eukaryotic human augmenter of liver regeneration (hALR) and to study their biological activity. METHODS: hALRcDNA clone was obtained from plasmid pGEM-T-hALR, and cDNA was subcloned into the prokatyotic expression vector pGEX-4T-2. The recombinant vector and pGEX-4T-2hALR were identified by enzyme digestion and DNA sequencing and transformed into E coli JM109. The positively selected clone was induced by the expression of GST-hALR fusion protein with IPTG, then the fusion protein was purified by glutathine s-transferase (GST) sepharose 4B affinity chromatography, cleaved by thrombin and the hALR monomer was obtained and detected by measuring H thymidine incorporation. RESULTS: The product of PCR from plasmid pGEM-T-hALR was examined by 1.5% sepharose electrophoresis. The specific strap was coincident with the theoretical one. The sequence was accurate and pGEX-4T-hALP digested by enzymes was coincident with the theoretical one. The sequence was accurate and the fragment was inserted in the positive direction. The recombinant vector was transformed into E coli JM109. SDS-PAGE proved that the induced expressive fusion protein showed a single band with a molecular weight of 41 kDa. The product was purified and cleaved. The molecular weights of GST and hALR were 26 kDa, 15 kDa respectively. The recombinant fusion protein accounted for 31% of the total soluble protein of bacterial lysate. HALR added to the culture medium of adult rat hepatocytes in primary culture and HepG2 cell line could significantly enhance the rate of DNA synthesis compared to the relevant control groups (P < 0.01). CONCLUSION: Purified hALR has the ability to stimulate DNA synthesis of adult rat hepatocytes in primary culture and HepG2 cells in vitro, and can provide evidence for its clinical application. PMID:16865786

  9. Estradiol and chlordecone (Kepone) decrease adenosine 3'5'-cyclic monophosphate concentrations in the ovariectomized immature rat uterus.

    PubMed

    Johnson, D C; Banerjee, S; Chatterjee, S

    1995-10-01

    Adenosine 3'5'-cyclic monophosphate (cAMP) has been repeatedly shown to mimic some actions of estrogen in the rat uterus. However, the relationship between estrogens and uterine cAMP remains controversial. The effect of chronic exposure (3 days) to a biologically potent, long-acting estrogen, estradiol benzoate (EB), or the xenoestrogen chlordecone (Kepone), which has a long half-life in the circulation, was examined in ovariectomized immature rats. Both compounds, when administered in doses that provided equal increases in uterine weight, produced equivalent decreases in uterine cAMP content. Although the decrease in cAMP was apparent within 48 hr, it was more pronounced at 72 hr. There was no reduction in cAMP produced in response to direct stimulation of uterine adenylyl cyclase by forskolin, indicating that loss of the enzyme was not a factor in the lowering of cAMP content. The pure anti-estrogen ICI-182,780, in a dose-dependent fashion, prevented the action the estradiol benzoate and chlordecone, suggesting that the lowering of cAMP was dependent on an estrogen receptor. The physiological significance of reduced uterine cAMP with chronic estrogen treatment remains to be determined. PMID:7545817

  10. Detection of driver metabolites in the human liver metabolic network using structural controllability analysis

    PubMed Central

    2014-01-01

    Background Abnormal states in human liver metabolism are major causes of human liver diseases ranging from hepatitis to hepatic tumor. The accumulation in relevant data makes it feasible to derive a large-scale human liver metabolic network (HLMN) and to discover important biological principles or drug-targets based on network analysis. Some studies have shown that interesting biological phenomenon and drug-targets could be discovered by applying structural controllability analysis (which is a newly prevailed concept in networks) to biological networks. The exploration on the connections between structural controllability theory and the HLMN could be used to uncover valuable information on the human liver metabolism from a fresh perspective. Results We applied structural controllability analysis to the HLMN and detected driver metabolites. The driver metabolites tend to have strong ability to influence the states of other metabolites and weak susceptibility to be influenced by the states of others. In addition, the metabolites were classified into three classes: critical, high-frequency and low-frequency driver metabolites. Among the identified 36 critical driver metabolites, 27 metabolites were found to be essential; the high-frequency driver metabolites tend to participate in different metabolic pathways, which are important in regulating the whole metabolic systems. Moreover, we explored some other possible connections between the structural controllability theory and the HLMN, and find that transport reactions and the environment play important roles in the human liver metabolism. Conclusion There are interesting connections between the structural controllability theory and the human liver metabolism: driver metabolites have essential biological functions; the crucial role of extracellular metabolites and transport reactions in controlling the HLMN highlights the importance of the environment in the health of human liver metabolism. PMID:24885538

  11. In Vitro Generation of Functional Liver Organoid-Like Structures Using Adult Human Cells

    PubMed Central

    Ramachandran, Sarada Devi; Schirmer, Katharina; Münst, Bernhard; Heinz, Stefan; Ghafoory, Shahrouz; Wölfl, Stefan; Simon-Keller, Katja; Marx, Alexander; Øie, Cristina Ionica; Ebert, Matthias P.; Walles, Heike

    2015-01-01

    In this study we used differentiated adult human upcyte® cells for the in vitro generation of liver organoids. Upcyte® cells are genetically engineered cell strains derived from primary human cells by lenti-viral transduction of genes or gene combinations inducing transient proliferation capacity (upcyte® process). Proliferating upcyte® cells undergo a finite number of cell divisions, i.e., 20 to 40 population doublings, but upon withdrawal of proliferation stimulating factors, they regain most of the cell specific characteristics of primary cells. When a defined mixture of differentiated human upcyte® cells (hepatocytes, liver sinusoidal endothelial cells (LSECs) and mesenchymal stem cells (MSCs)) was cultured in vitro on a thick layer of Matrigel™, they self-organized to form liver organoid-like structures within 24 hours. When further cultured for 10 days in a bioreactor, these liver organoids show typical functional characteristics of liver parenchyma including activity of cytochromes P450, CYP3A4, CYP2B6 and CYP2C9 as well as mRNA expression of several marker genes and other enzymes. In summary, we hereby describe that 3D functional hepatic structures composed of primary human cell strains can be generated in vitro. They can be cultured for a prolonged period of time and are potentially useful ex vivo models to study liver functions. PMID:26488607

  12. Monoclonal antibodies to monoamine oxidase B and another mitochondrial protein from human liver.

    PubMed Central

    Billett, E E; Mayer, R J

    1986-01-01

    A monoclonal antibody has been generated to human liver monoamine oxidase (MAO) B by fusion of mouse myeloma cells with spleen cells from a mouse immunized with a mixture of semi-purified MAO A and MAO B. The antibody, 3F12/G10, an immunoglobulin G1, reacts with its antigen in cryostat sections of human liver, showing an intracellular particulate distribution as demonstrated by immunoperoxidase staining. The antibody indirectly precipitates [3H]pargyline-labelled human MAO B both from liver and platelet extracts but fails to precipitate MAO A from liver extracts. The antibody does not recognise rat liver MAO B, showing that the determinant is not universally expressed on MAO B. The antibody has no effect on the catalytic activity of MAO B. Other monoclonal antibodies were generated but they are directed to a protein with a subunit Mr of 54 000, a contaminant of the MAO preparation. One of these antibodies, A8/C2, an IgG2a, reacts with the same protein in both rat and human liver extracts. Images Fig. 1. Fig. 3. PMID:3527152

  13. In Vitro Generation of Functional Liver Organoid-Like Structures Using Adult Human Cells.

    PubMed

    Ramachandran, Sarada Devi; Schirmer, Katharina; Münst, Bernhard; Heinz, Stefan; Ghafoory, Shahrouz; Wölfl, Stefan; Simon-Keller, Katja; Marx, Alexander; Øie, Cristina Ionica; Ebert, Matthias P; Walles, Heike; Braspenning, Joris; Breitkopf-Heinlein, Katja

    2015-01-01

    In this study we used differentiated adult human upcyte® cells for the in vitro generation of liver organoids. Upcyte® cells are genetically engineered cell strains derived from primary human cells by lenti-viral transduction of genes or gene combinations inducing transient proliferation capacity (upcyte® process). Proliferating upcyte® cells undergo a finite number of cell divisions, i.e., 20 to 40 population doublings, but upon withdrawal of proliferation stimulating factors, they regain most of the cell specific characteristics of primary cells. When a defined mixture of differentiated human upcyte® cells (hepatocytes, liver sinusoidal endothelial cells (LSECs) and mesenchymal stem cells (MSCs)) was cultured in vitro on a thick layer of Matrigel™, they self-organized to form liver organoid-like structures within 24 hours. When further cultured for 10 days in a bioreactor, these liver organoids show typical functional characteristics of liver parenchyma including activity of cytochromes P450, CYP3A4, CYP2B6 and CYP2C9 as well as mRNA expression of several marker genes and other enzymes. In summary, we hereby describe that 3D functional hepatic structures composed of primary human cell strains can be generated in vitro. They can be cultured for a prolonged period of time and are potentially useful ex vivo models to study liver functions.

  14. Studies on adenosine triphosphate transphosphorylases. Human isoenzymes of adenylate kinase: isolation and physicochemical comparison of the crystalline human ATP-AMP transphosphorylases from muscle and liver.

    PubMed

    Kuby, S A; Fleming, G; Frischat, A; Cress, M C; Hamada, M

    1983-02-10

    Procedures are described for the isolation, in crystalline form, of the adenylate kinases from autopsy samples of human muscle and from human liver. Weight average molecular weights were determined by sedimentation equilibrium to be 22,000 (+/- 700) and 25,450 (+/- 160) for the human muscle and liver isoenzymes, respectively. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis, their molecular weights were estimated to be 21,700 and 26,500 for the muscle and liver enzymes, respectively. Both isoenzymes are accordingly monomeric proteins in their native state. Amino acid analyses are reported here for the normal human liver, calf liver, and rabbit liver adenylate kinases and compared with the normal human muscle, calf muscle, and rabbit muscle myokinases. The liver types as a group and the muscle types as a group show a great deal of homology, but some distinct differences are evident between the liver and muscle enzyme groups, especially in the number of residues of His, Pro, half-cystine, and the presence of tryptophan in the liver enzymes. The normal human liver adenylate kinase, as isolated in this report, has proved to be similar in its properties, if not identical, to the adenylate kinase isolated directly from human liver mitochondria (Hamada, M., Sumida, M., Okuda, H., Watanabe, T., Nojima, M., and Kuby, S. A. (1982) J. Biol. Chem. 257, 13120-13128). Therefore, the liver-type adenylate kinase may be considered a mitochondrial type.

  15. Human precision-cut liver slices as a model to test antifibrotic drugs in the early onset of liver fibrosis.

    PubMed

    Westra, Inge M; Mutsaers, Henricus A M; Luangmonkong, Theerut; Hadi, Mackenzie; Oosterhuis, Dorenda; de Jong, Koert P; Groothuis, Geny M M; Olinga, Peter

    2016-09-01

    Liver fibrosis is the progressive accumulation of connective tissue ultimately resulting in loss of organ function. Currently, no effective antifibrotics are available due to a lack of reliable human models. Here we investigated the fibrotic process in human precision-cut liver slices (PCLS) and studied the efficacy of multiple putative antifibrotic compounds. Our results demonstrated that human PCLS remained viable for 48h and the early onset of fibrosis was observed during culture, as demonstrated by an increased gene expression of Heat Shock Protein 47 (HSP47) and Pro-Collagen 1A1 (PCOL1A1) as well as increased collagen 1 protein levels. SB203580, a specific inhibitor of p38 mitogen-activated protein kinase (MAPK) showed a marked decrease in HSP47 and PCOL1A1 gene expression, whereas specific inhibitors of Smad 3 and Rac-1 showed no or only minor effects. Regarding the studied antifibrotics, gene levels of HSP47 and PCOL1A1 could be down-regulated with sunitinib and valproic acid, while PCOL1A1 expression was reduced following treatment with rosmarinic acid, tetrandrine and pirfenidone. These results are in contrast with prior data obtained in rat PCLS, indicating that antifibrotic drug efficacy is clearly species-specific. Thus, human PCLS is a promising model for liver fibrosis. Moreover, MAPK signaling plays an important role in the onset of fibrosis in this model and transforming growth factor beta pathway inhibitors appear to be more effective than platelet-derived growth factor pathway inhibitors in halting fibrogenesis in PCLS. PMID:27235791

  16. Characterization of ethanol-inducible human liver N-nitrosodimethylamine demethylase

    SciTech Connect

    Wrighton, S.A.; Thomas P.E.; Molowa, D.T.; Haniu, M.; Shively, J.E.; Maines, S.L.; Watkins, P.B.; Parker, G.; Mendez-Picon, G.; Levin, W.; Guzelian, P.S.

    1986-11-04

    Through the use of monospecific antibodies directed against hepatic cytochrome P-450j, an enzyme induced in rats treated with ethanol or isoniazid, we have purified from human liver the related cytochrome P-450 termed HLj. HLj resembles rat P-450j and P-450 LM3a, the homologous cytochrome in rabbit liver, in its NH/sub 2/-terminal amino acid sequence, in being in highest concentration in liver microsome samples prepared from two patients intoxicated by ethanol and one patient given isoniazid, and in catalyzing the metabolic activation of the procarcinogen N-nitrosodimethylamine. Furthermore, each of nine human liver RNA samples contained a species of mRNA hybridizable to a cloned HLj cDNA. We conclude that HLj is related by structure, function, and some regulator characteristics to rat P-450j and rabbit P-450 LM3a, cytochromes critical for metabolism of several clinically relevant cytotoxic and carcinogenic agents.

  17. Metabolic profiling during ex vivo machine perfusion of the human liver

    PubMed Central

    Bruinsma, Bote G.; Sridharan, Gautham V.; Weeder, Pepijn D.; Avruch, James H.; Saeidi, Nima; Özer, Sinan; Geerts, Sharon; Porte, Robert J.; Heger, Michal; van Gulik, Thomas M.; Martins, Paulo N.; Markmann, James F.; Yeh, Heidi; Uygun, Korkut

    2016-01-01

    As donor organ shortages persist, functional machine perfusion is under investigation to improve preservation of the donor liver. The transplantation of donation after circulatory death (DCD) livers is limited by poor outcomes, but its application may be expanded by ex vivo repair and assessment of the organ before transplantation. Here we employed subnormothermic (21 °C) machine perfusion of discarded human livers combined with metabolomics to gain insight into metabolic recovery during machine perfusion. Improvements in energetic cofactors and redox shifts were observed, as well as reversal of ischemia-induced alterations in selected pathways, including lactate metabolism and increased TCA cycle intermediates. We next evaluated whether DCD livers with steatotic and severe ischemic injury could be discriminated from ‘transplantable’ DCD livers. Metabolomic profiling was able to cluster livers with similar metabolic patterns based on the degree of injury. Moreover, perfusion parameters combined with differences in metabolic factors suggest variable mechanisms that result in poor energy recovery in injured livers. We conclude that machine perfusion combined with metabolomics has significant potential as a clinical instrument for the assessment of preserved livers. PMID:26935866

  18. The Human Liver Proteome Project (HLPP) Workshop August 2008, Amsterdam, The Netherlands

    PubMed Central

    Beretta, Laura

    2015-01-01

    An HLPP workshop was held in conjunction with the 7th HUPO 2008 World Congress in Amsterdam, The Netherlands. The workshop was chaired by Laura Beretta (Fred Hutchinson Cancer Research Center (FHCRC)) and Xiaohong Qian (Beijing Proteome Research Center (BPRC)). The workshop was organized in three sessions: Session 1: The Human Proteome Project: the liver perspective, moderated by John Bergeron (McGill University); Session 2: The comparative analysis of the liver and plasma proteomes, moderated by Young-Ki Paik (Yonsei University) and Session 3: Opportunities for the study of liver diseases within the HLPP, moderated by Chantal Housset (INSERM, France). PMID:19862759

  19. Analysis of histone modifications at human ribosomal DNA in liver cancer cell

    PubMed Central

    Yu, Feng; Shen, Xingyong; Fan, Li; Yu, Zhaocai

    2015-01-01

    Human liver cancer is the cancer commonly seen clinically. The transcription of ribosomal DNA (rDNA) is a critical step for cells, and epigenetic marks such as post-translational histone modifications have been involved in the regulation of rDNA transcription. But less is known about the pathogenesis of the liver cancers concerning the rDNA transcription regulation. Here we aligned the ChIP-seq data of histone modification markers and CTCF to the human genome assembly which contains a single rDNA repeat in human liver cancer cell and validated their distribution with ChIP-QPCR. Human liver cancer cell possesses a higher enrichment of H3K4me1 and H3K27me3 at ~28 kb within the intergenic spacer (IGS) of rDNA and a higher enrichment of H3K4me3 and H3K27ac upstream of TSS. Furtherly, we studied whether UBF could affect histone modification markers and CTCF at rDNA in human liver cancer cell. UBF depletion leads to a decrease of gene activation mark H3K4me3 across the rDNA promoter. And other histone modification marks and CTCF were not altered after UBF depletion. Taken together, our data showed a high resolution map of histone modification marks at rDNA in human liver cancer cell and provide novel evidence to decipher chromatin-mediated regulation of rDNA in liver cancer. PMID:26657029

  20. A new human 3D-liver model unravels the role of galectins in liver infection by the parasite Entamoeba histolytica.

    PubMed

    Petropolis, Debora B; Faust, Daniela M; Deep Jhingan, Gagan; Guillen, Nancy

    2014-09-01

    Investigations of human parasitic diseases depend on the availability of appropriate in vivo animal models and ex vivo experimental systems, and are particularly difficult for pathogens whose exclusive natural hosts are humans, such as Entamoeba histolytica, the protozoan parasite responsible for amoebiasis. This common infectious human disease affects the intestine and liver. In the liver sinusoids E. histolytica crosses the endothelium and penetrates into the parenchyma, with the concomitant initiation of inflammatory foci and subsequent abscess formation. Studying factors responsible for human liver infection is hampered by the complexity of the hepatic environment and by the restrictions inherent to the use of human samples. Therefore, we built a human 3D-liver in vitro model composed of cultured liver sinusoidal endothelial cells and hepatocytes in a 3D collagen-I matrix sandwich. We determined the presence of important hepatic markers and demonstrated that the cell layers function as a biological barrier. E. histolytica invasion was assessed using wild-type strains and amoebae with altered virulence or different adhesive properties. We showed for the first time the dependence of endothelium crossing upon amoebic Gal/GalNAc lectin. The 3D-liver model enabled the molecular analysis of human cell responses, suggesting for the first time a crucial role of human galectins in parasite adhesion to the endothelial cells, which was confirmed by siRNA knockdown of galectin-1. Levels of several pro-inflammatory cytokines, including galectin-1 and -3, were highly increased upon contact of E. histolytica with the 3D-liver model. The presence of galectin-1 and -3 in the extracellular medium stimulated pro-inflammatory cytokine release, suggesting a further role for human galectins in the onset of the hepatic inflammatory response. These new findings are relevant for a better understanding of human liver infection by E. histolytica.

  1. A New Human 3D-Liver Model Unravels the Role of Galectins in Liver Infection by the Parasite Entamoeba histolytica

    PubMed Central

    Petropolis, Debora B.; Faust, Daniela M.; Deep Jhingan, Gagan; Guillen, Nancy

    2014-01-01

    Investigations of human parasitic diseases depend on the availability of appropriate in vivo animal models and ex vivo experimental systems, and are particularly difficult for pathogens whose exclusive natural hosts are humans, such as Entamoeba histolytica, the protozoan parasite responsible for amoebiasis. This common infectious human disease affects the intestine and liver. In the liver sinusoids E. histolytica crosses the endothelium and penetrates into the parenchyma, with the concomitant initiation of inflammatory foci and subsequent abscess formation. Studying factors responsible for human liver infection is hampered by the complexity of the hepatic environment and by the restrictions inherent to the use of human samples. Therefore, we built a human 3D-liver in vitro model composed of cultured liver sinusoidal endothelial cells and hepatocytes in a 3D collagen-I matrix sandwich. We determined the presence of important hepatic markers and demonstrated that the cell layers function as a biological barrier. E. histolytica invasion was assessed using wild-type strains and amoebae with altered virulence or different adhesive properties. We showed for the first time the dependence of endothelium crossing upon amoebic Gal/GalNAc lectin. The 3D-liver model enabled the molecular analysis of human cell responses, suggesting for the first time a crucial role of human galectins in parasite adhesion to the endothelial cells, which was confirmed by siRNA knockdown of galectin-1. Levels of several pro-inflammatory cytokines, including galectin-1 and -3, were highly increased upon contact of E. histolytica with the 3D-liver model. The presence of galectin-1 and -3 in the extracellular medium stimulated pro-inflammatory cytokine release, suggesting a further role for human galectins in the onset of the hepatic inflammatory response. These new findings are relevant for a better understanding of human liver infection by E. histolytica. PMID:25211477

  2. Human mesenchymal stem cell-engineered hepatic cell sheets accelerate liver regeneration in mice

    PubMed Central

    Itaba, Noriko; Matsumi, Yoshiaki; Okinaka, Kaori; Ashla, An Afida; Kono, Yohei; Osaki, Mitsuhiko; Morimoto, Minoru; Sugiyama, Naoyuki; Ohashi, Kazuo; Okano, Teruo; Shiota, Goshi

    2015-01-01

    Mesenchymal stem cells (MSCs) are an attractive cell source for cell therapy. Based on our hypothesis that suppression of Wnt/β-catenin signal enhances hepatic differentiation of human MSCs, we developed human mesenchymal stem cell-engineered hepatic cell sheets by a small molecule compound. Screening of 10 small molecule compounds was performed by WST assay, TCF reporter assay, and albumin mRNA expression. Consequently, hexachlorophene suppressed TCF reporter activity in time- and concentration-dependent manner. Hexachlorophene rapidly induced hepatic differentiation of human MSCs judging from expression of liver-specific genes and proteins, PAS staining, and urea production. The effect of orthotopic transplantation of human mesenchymal stem cell-engineered hepatic cell sheets against acute liver injury was examined in one-layered to three-layered cell sheets system. Transplantation of human mesenchymal stem cell-engineered hepatic cell sheets enhanced liver regeneration and suppressed liver injury. The survival rates of the mice were significantly improved. High expression of complement C3 and its downstream signals including C5a, NF-κB, and IL-6/STAT-3 pathway was observed in hepatic cell sheets-grafted tissues. Expression of phosphorylated EGFR and thioredoxin is enhanced, resulting in reduction of oxidative stress. These findings suggest that orthotopic transplantation of hepatic cell sheets manufactured from MSCs accelerates liver regeneration through complement C3, EGFR and thioredoxin. PMID:26553591

  3. 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.

  4. Systemic chimerism in human female recipients of male livers.

    PubMed

    Starzl, T E; Demetris, A J; Trucco, M; Ramos, H; Zeevi, A; Rudert, W A; Kocova, M; Ricordi, C; Ildstad, S; Murase, N

    1992-10-10

    We have previously reported data from clinical and laboratory animal observations which suggest that organ tolerance after transplantation depends on a state of balanced lymphodendritic cell chimerism between the host and donor graft. We have sought further evidence to support this hypothesis by investigating HLA-mismatched liver allograft recipients. 9 of 9 female recipients of livers from male donors had chimerism in their allografts and extrahepatic tissues, according to in-situ hybridisation and molecular techniques 10 to 19 years posttransplantation. In 8 women with good graft function, evidence of the Y chromosome was found in the blood (6/8), skin (8/8), and lymph nodes (7/8). A ninth patient whose transplant failed after 12 years from recurrent chronic viral hepatitis had chimerism in her lymph nodes, skin, jejunum, and aorta at the time of retransplantation. Although cell migration is thought to take place after all types of transplantation, the large population of migratory cells in, and the extent of their seeding from, hepatic grafts may explain the privileged tolerogenicity of the liver compared with other organs.

  5. Functional Integrity of the Chimeric (Humanized) Mouse Liver: Enzyme Zonation, Physiologic Spaces, and Hepatic Enzymes and Transporters.

    PubMed

    Chow, Edwin C Y; Wang, Jason Z Ya; Quach, Holly P; Tang, Hui; Evans, David C; Li, Albert P; Silva, Jose; Pang, K Sandy

    2016-09-01

    Chimeric mouse liver models are useful in vivo tools for human drug metabolism studies; however, liver integrity and the microcirculation remain largely uninvestigated. Hence, we conducted liver perfusion studies to examine these attributes in FRGN [Fah(-/-), Rag2(-/-), and Il2rg(-/-), NOD strain] livers (control) and chimeric livers repopulated with mouse (mFRGN) or human (hFRGN) hepatocytes. In single-pass perfusion studies (2.5 ml/min), outflow dilution profiles of noneliminated reference indicators ((51)Cr-RBC, (125)I-albumin, (14)C-sucrose, and (3)H-water) revealed preservation of flow-limited distribution and reduced water and albumin spaces in hFRGN livers compared with FRGN livers, a view supported microscopically by tightly packed sinusoids. With prograde and retrograde perfusion of harmol (50 µM) in FRGN livers, an anterior sulfation (Sult1a1) over the posterior distribution of glucuronidation (Ugt1a1) activity was preserved, evidenced by the 42% lower sulfation-to-glucuronidation ratio (HS/HG) and 14% higher harmol extraction ratio (E) upon switching from prograde to retrograde flow. By contrast, zonation was lost in mFRGN and hFRGN livers, with HS/HG and E for both flows remaining unchanged. Remnant mouse genes persisted in hFRGN livers (10%-300% those of FRGN). When hFRGN livers were compared with human liver tissue, higher UGT1A1 and MRP2, lower MRP3, and unchanged SULT1A1 and MRP4 mRNA expression were observed. Total Sult1a1/SULT1A1 protein expression in hFRGN livers was higher than that of FRGN livers, consistent with higher harmol sulfate formation. The composite data on humanized livers suggest a loss of zonation, lack of complete liver humanization, and persistence of murine hepatocyte activities leading to higher sulfation.

  6. All-In-One: Advanced preparation of Human Parenchymal and Non-Parenchymal Liver Cells

    PubMed Central

    Werner, Melanie; Driftmann, Sabrina; Kleinehr, Kathrin; Kaiser, Gernot M.; Mathé, Zotlan; Treckmann, Juergen-Walter; Paul, Andreas; Skibbe, Kathrin; Timm, Joerg; Canbay, Ali; Gerken, Guido; Schlaak, Joerg F.; Broering, Ruth

    2015-01-01

    Background & Aims Liver cells are key players in innate immunity. Thus, studying primary isolated liver cells is necessary for determining their role in liver physiology and pathophysiology. In particular, the quantity and quality of isolated cells are crucial to their function. Our aim was to isolate a large quantity of high-quality human parenchymal and non-parenchymal cells from a single liver specimen. Methods Hepatocytes, Kupffer cells, liver sinusoidal endothelial cells, and stellate cells were isolated from liver tissues by collagenase perfusion in combination with low-speed centrifugation, density gradient centrifugation, and magnetic-activated cell sorting. The purity and functionality of cultured cell populations were controlled by determining their morphology, discriminative cell marker expression, and functional activity. Results Cell preparation yielded the following cell counts per gram of liver tissue: 2.0±0.4×107 hepatocytes, 1.8±0.5×106 Kupffer cells, 4.3±1.9×105 liver sinusoidal endothelial cells, and 3.2±0.5×105 stellate cells. Hepatocytes were identified by albumin (95.5±1.7%) and exhibited time-dependent activity of cytochrome P450 enzymes. Kupffer cells expressed CD68 (94.5±1.2%) and exhibited phagocytic activity, as determined with 1μm latex beads. Endothelial cells were CD146+ (97.8±1.1%) and exhibited efficient uptake of acetylated low-density lipoprotein. Hepatic stellate cells were identified by the expression of α-smooth muscle actin (97.1±1.5%). These cells further exhibited retinol (vitamin A)-mediated autofluorescence. Conclusions Our isolation procedure for primary parenchymal and non-parenchymal liver cells resulted in cell populations of high purity and quality, with retained physiological functionality in vitro. Thus, this system may provide a valuable tool for determining liver function and disease. PMID:26407160

  7. [Liver and artificial liver].

    PubMed

    Chamuleau, R A

    1998-06-01

    Despite good results of orthotopic liver transplantation in patients with fulminant hepatic failure the need still exists for an effective and safe artificial liver, able to temporarily take over the complex liver function so as to bridge the gap with transplantation or regeneration. Attempts to develop non-biological artificial livers have failed, mostly when controlled clinical trials were performed. In the last decade several different types of bioartificial livers have been devised, in which the biocomponent consists of freshly isolated porcine hepatocytes or a human hepatoblastoma cell line. The majority use semipermeable hollow fibers known from artificial kidney devices. The liver cells may lie either inside or outside the lumen of these fibers. In vitro analysis of liver function and animal experimental work showing that the bioartificial liver increases survival justify clinical application. Bioartificial livers are connected to patients extracorporeally by means of plasmapheresis circuit for periods of about 6 hours. In different trials about 40 patients with severe liver failure have been treated. No important adverse effects have not been reported in these phase I trials. Results of controlled studies are urgently needed. As long as no satisfactory immortalised human liver cell line with good function is available, porcine hepatocytes will remain the first choice, provided transmission of porcine pathogens to man is prevented. PMID:9752034

  8. Esterase detoxication of acetylcholinesterase inhibitors using human liver samples in vitro.

    PubMed

    Moser, Virginia C; Padilla, Stephanie

    2016-04-15

    Organophosphorus (OP) and N-methylcarbamate pesticides inhibit acetylcholinesterase (AChE), but differences in metabolism and detoxication can influence potency of these pesticides across and within species. Carboxylesterase (CaE) and A-esterase (paraoxonase, PON1) are considered factors underlying age-related sensitivity differences. We used an in vitro system to measure detoxication of AChE-inhibiting pesticides mediated via these esterases. Recombinant human AChE was used as a bioassay of inhibitor concentration following incubation with detoxifying tissue: liver plus Ca(+2) (to stimulate PON1s, measuring activity of both esterases) or EGTA (to inhibit PON1s, thereby measuring CaE activity). AChE inhibitory concentrations of aldicarb, chlorpyrifos oxon, malaoxon, methamidophos, oxamyl, paraoxon, and methylparaoxon were incubated with liver homogenates from adult male rat or one of 20 commercially provided human (11-83 years of age) liver samples. Detoxication was defined as the difference in inhibition produced by the pesticide alone and inhibition measured in combination with liver plus Ca(+2) or liver plus EGTA. Generally, rat liver produced more detoxication than did the human samples. There were large detoxication differences across human samples for some pesticides (especially malaoxon, chlorpyrifos oxon) but not for others (e.g., aldicarb, methamidophos); for the most part these differences did not correlate with age or sex. Chlorpyrifos oxon was fully detoxified only in the presence of Ca(+2) in both rat and human livers. Detoxication of paraoxon and methylparaoxon in rat liver was greater with Ca(+2), but humans showed less differentiation than rats between Ca(+2) and EGTA conditions. This suggests the importance of PON1 detoxication for these three OPs in the rat, but mostly only for chlorpyrifos oxon in human samples. Malaoxon was detoxified similarly with Ca(+2) or EGTA, and the differences across humans correlated with metabolism of p

  9. Glucuronidation of Monohydroxylated Warfarin Metabolites by Human Liver Microsomes and Human Recombinant UDP-Glucuronosyltransferases

    PubMed Central

    Zielinska, Agnieszka; Lichti, Cheryl F.; Bratton, Stacie; Mitchell, Neil C.; Gallus-Zawada, Anna; Le, Vi-Huyen; Finel, Moshe; Miller, Grover P.; Radominska-Pandya, Anna; Moran, Jeffery H.

    2008-01-01

    Our understanding of human phase II metabolic pathways which facilitate detoxification and excretion of warfarin (Coumadin) is limited. The goal of this study was to test the hypothesis that there are specific human hepatic and extrahepatic UDP-glucuronosyltransferase (UGT) isozymes, which are responsible for conjugating warfarin and hydroxylated metabolites of warfarin. Glucuronidation activity of human liver microsomes (HLMs) and eight human recombinant UGTs toward (R)- and (S)-warfarin, racemic warfarin, and major cytochrome P450 metabolites of warfarin (4′-, 6-, 7-, 8-, and 10-hydroxywarfarin) has been assessed. HLMs, UGT1A1, 1A8, 1A9, and 1A10 showed glucuronidation activity toward 4′-, 6-, 7-, and/or 8-hydroxywarfarin with Km values ranging from 59 to 480 μM and Vmax values ranging from 0.03 to 0.78 μM/min/mg protein. Tandem mass spectrometry studies and structure comparisons suggested glucuronidation was occurring at the C4′-,C6-, C7-, and C8-positions. Of the hepatic UGT isozymes tested, UGT1A9 exclusively metabolized 8-hydroxywarfarin, whereas UGT1A1 metabolized 6-, 7-, and 8-hydroxywarfarin. Studies with extrahepatic UGT isoforms showed that UGT1A8 metabolized 7- and 8-hydroxywarfarin and that UGT1A10 glucuronidated 4′-, 6-, 7-, and 8-hydroxywarfarin. UGT1A4, 1A6, 1A7, and 2B7 did not have activity with any substrate, and none of the UGT isozymes evaluated catalyzed reactions with (R)- and (S)-warfarin, racemic warfarin, or 10-hydroxywarfarin. This is the first study identifying and characterizing specific human UGT isozymes, which glucuronidate major cytochrome P450 metabolites of warfarin with similar metabolic rates known to be associated with warfarin metabolism. Continued characterization of these pathways may enhance our ability to reduce life-threatening and costly complications associated with warfarin therapy. PMID:17921187

  10. Liver fibrosis in human immunodeficiency virus/hepatitis C virus coinfection: Diagnostic methods and clinical impact

    PubMed Central

    Sagnelli, Caterina; Martini, Salvatore; Pisaturo, Mariantonietta; Pasquale, Giuseppe; Macera, Margherita; Zampino, Rosa; Coppola, Nicola; Sagnelli, Evangelista

    2015-01-01

    Several non-invasive surrogate methods have recently challenged the main role of liver biopsy in assessing liver fibrosis in hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients, applied to avoid the well-known side effects of liver puncture. Serological tests involve the determination of biochemical markers of synthesis or degradation of fibrosis, tests not readily available in clinical practice, or combinations of routine tests used in chronic hepatitis and HIV/HCV coinfection. Several radiologic techniques have also been proposed, some of which commonly used in clinical practice. The studies performed to compare the prognostic value of non-invasive surrogate methods with that of the degree of liver fibrosis assessed on liver tissue have not as yet provided conclusive results. Each surrogate technique has shown some limitations, including the risk of over- or under-estimating the extent of liver fibrosis. The current knowledge on liver fibrosis in HIV/HCV-coinfected patients will be summarized in this review article, which is addressed in particular to physicians involved in this setting in their clinical practice. PMID:26523204

  11. Prediction of Drug-Induced Liver Injury in HepG2 Cells Cultured with Human Liver Microsomes.

    PubMed

    Choi, Jong Min; Oh, Soo Jin; Lee, Ji-Yoon; Jeon, Jang Su; Ryu, Chang Seon; Kim, Young-Mi; Lee, Kiho; Kim, Sang Kyum

    2015-05-18

    Drug-induced liver injury (DILI) via metabolic activation by drug-metabolizing enzymes, especially cytochrome P450 (CYP), is a major cause of drug failure and drug withdrawal. In this study, an in vitro model using HepG2 cells in combination with human liver microsomes was developed for the prediction of DILI. The cytotoxicity of cyclophosphamide, a model drug for bioactivation, was augmented in HepG2 cells cultured with microsomes in a manner dependent on exposure time, microsomal protein concentration, and NADPH. Experiments using pan- or isoform-selective CYP inhibitors showed that CYP2B6 and CYP3A4 are responsible for the bioactivation of cyclophosphamide. In a metabolite identification study employing LC-ESI-QTrap and LC-ESI-QTOF, cyclophosphamide metabolites including phosphoramide mustard, a toxic metabolite, were detected in HepG2 cells cultured with microsomes, but not without microsomes. The cytotoxic effects of acetaminophen and diclofenac were also potentiated by microsomes. The potentiation of acetaminophen cytotoxicity was dependent on CYP-dependent metabolism, and the augmentation of diclofenac cytotoxicity was not mediated by either CYP- or UDP-glucuronosyltransferase-dependent metabolism. The cytotoxic effects of leflunomide, nefazodone, and bakuchiol were attenuated by microsomes. The detoxication of leflunomide by microsomes was attributed to mainly CYP3A4-dependent metabolism. The protective effect of microsomes against nefazodone cytotoxicity was dependent on both CYP-mediated metabolism and nonspecific protein binding. Nonspecific protein binding but not CYP-dependent metabolism played a critical role in the attenuation of bakuchiol cytotoxicity. The present study suggests that HepG2 cells cultured with human liver microsomes can be a reliable model in which to predict DILI via bioactivation by drug metabolizing enzymes.

  12. Content and activity of human liver microsomal protein and prediction of individual hepatic clearance in vivo

    PubMed Central

    Zhang, Haifeng; Gao, Na; Tian, Xin; Liu, Tingting; Fang, Yan; Zhou, Jun; Wen, Qiang; Xu, Binbin; Qi, Bing; Gao, Jie; Li, Hongmeng; Jia, Linjing; Qiao, Hailing

    2015-01-01

    The lack of information concerning individual variation in content and activity of human liver microsomal protein is one of the most important obstacles for designing personalized medicines. We demonstrated that the mean value of microsomal protein per gram of liver (MPPGL) was 39.46 mg/g in 128 human livers and up to 19-fold individual variations existed. Meanwhile, the metabolic activities of 10 cytochrome P450 (CYPs) were detected in microsomes and liver tissues, respectively, which showed huge individual variations (200-fold). Compared with microsomes, the activities of liver tissues were much suitable to express the individual variations of CYP activities. Furthermore, individual variations in the in vivo clearance of tolbutamide were successfully predicted with the individual parameter values. In conclusion, we offer the values for MPPGL contents in normal liver tissues and build a new method to assess the in vitro CYP activities. In addition, large individual variations exist in predicted hepatic clearance of tolbutamide. These findings provide important physiological parameters for physiologically-based pharmacokinetics models and thus, establish a solid foundation for future development of personalized medicines. PMID:26635233

  13. The human liver glycogen synthase isozyme gene is located on the short arm of chromosome 12

    SciTech Connect

    Nuttall, F.Q.; Gannon, M.C. ); Kubic, V.L.; Hoyt, K.J. )

    1994-01-15

    Glycogen synthase catalyzes the rate-limiting step in glycogen synthesis. Its activity is regulated by a complex phosphorylation-dephosphorylation mechanism and by allosteric stimulators and inhibitors. Two isozymes of synthase, a skeletal muscle type and liver type, have been identified in rabbit and rat tissues using specific polyclonal antibodies. The skeletal muscle type isozyme is present in several organs in addition to skeletal muscle; the liver isozyme has been identified only in liver. Recently, we have purified and characterized the human liver synthase isozyme. We also have cloned and sequenced the gene from a human liver cDNA library. Using the entire cDNA coding sequence as a probe, we report here the localization of the liver synthase isozyme gene to the short arm of chromosome 12. These studies revealed a centromeric signal on chromosome 12 together with signal to glycogen synthase on the short arm of this chromosome in the p11.2-p12.2 region. Measurements of the relative distance from the midpoint of the centromere to the signal corresponding to glycogen synthase suggests that the locus is in the p12.2 band rather than in the more centromeric location.

  14. Content and activity of human liver microsomal protein and prediction of individual hepatic clearance in vivo.

    PubMed

    Zhang, Haifeng; Gao, Na; Tian, Xin; Liu, Tingting; Fang, Yan; Zhou, Jun; Wen, Qiang; Xu, Binbin; Qi, Bing; Gao, Jie; Li, Hongmeng; Jia, Linjing; Qiao, Hailing

    2015-12-04

    The lack of information concerning individual variation in content and activity of human liver microsomal protein is one of the most important obstacles for designing personalized medicines. We demonstrated that the mean value of microsomal protein per gram of liver (MPPGL) was 39.46 mg/g in 128 human livers and up to 19-fold individual variations existed. Meanwhile, the metabolic activities of 10 cytochrome P450 (CYPs) were detected in microsomes and liver tissues, respectively, which showed huge individual variations (200-fold). Compared with microsomes, the activities of liver tissues were much suitable to express the individual variations of CYP activities. Furthermore, individual variations in the in vivo clearance of tolbutamide were successfully predicted with the individual parameter values. In conclusion, we offer the values for MPPGL contents in normal liver tissues and build a new method to assess the in vitro CYP activities. In addition, large individual variations exist in predicted hepatic clearance of tolbutamide. These findings provide important physiological parameters for physiologically-based pharmacokinetics models and thus, establish a solid foundation for future development of personalized medicines.

  15. High resolution proton magnetic resonance spectroscopy of human brain and liver

    SciTech Connect

    Barany, M.; Spigos, D.G.; Mok, E.; Venkatasubramanian, P.N.; Wilbur, A.C.; Langer, B.G.

    1987-01-01

    Water-suppressed and slice-selective proton spectra of live human brain exhibited several resonances that were tentatively assigned to metabolites such as N-acetylaspartate, glutamate, phosphocreatine and creatine, choline derivatives, and taurine. In the liver spectrum of a healthy volunteer, the major resonance was tentatively assigned to a fatty acyl methylene and the minor resonances to protons in carnitine, taurine, glutamate, and glutamine. In the spectrum of a cancerous liver, resonances in addition to those present in the normal liver were seen. Protein degradation in the liver with cancer was indicated by resonances from urea and from the ring protons in tryptophan, tyrosine, and phenylalanine. Furthermore, increased nucleic acid synthesis was indicated by resonances from nucleotide protons.

  16. All-Trans-Retinoic Acid Enhances Mitochondrial Function in Models of Human Liver.

    PubMed

    Tripathy, Sasmita; Chapman, John D; Han, Chang Y; Hogarth, Cathryn A; Arnold, Samuel L M; Onken, Jennifer; Kent, Travis; Goodlett, David R; Isoherranen, Nina

    2016-05-01

    All-trans-retinoic acid (atRA) is the active metabolite of vitamin A. The liver is the main storage organ of vitamin A, but activation of the retinoic acid receptors (RARs) in mouse liver and in human liver cell lines has also been shown. AlthoughatRA treatment improves mitochondrial function in skeletal muscle in rodents, its role in modulating mitochondrial function in the liver is controversial, and little data are available regarding the human liver. The aim of this study was to determine whetheratRA regulates hepatic mitochondrial activity.atRA treatment increased the mRNA and protein expression of multiple components of mitochondrialβ-oxidation, tricarboxylic acid (TCA) cycle, and respiratory chain. Additionally,atRA increased mitochondrial biogenesis in human hepatocytes and in HepG2 cells with and without lipid loading based on peroxisome proliferator activated receptor gamma coactivator 1αand 1βand nuclear respiratory factor 1 mRNA and mitochondrial DNA quantification.atRA also increasedβ-oxidation and ATP production in HepG2 cells and in human hepatocytes. Knockdown studies of RARα, RARβ, and PPARδrevealed that the enhancement of mitochondrial biogenesis andβ-oxidation byatRA requires peroxisome proliferator activated receptor delta. In vivo in mice,atRA treatment increased mitochondrial biogenesis markers after an overnight fast. Inhibition ofatRA metabolism by talarozole, a cytochrome P450 (CYP) 26 specific inhibitor, increased the effects ofatRA on mitochondrial biogenesis markers in HepG2 cells and in vivo in mice. These studies show thatatRA regulates mitochondrial function and lipid metabolism and that increasingatRA concentrations in human liver via CYP26 inhibition may increase mitochondrial biogenesis and fatty acidβ-oxidation and provide therapeutic benefit in diseases associated with mitochondrial dysfunction. PMID:26921399

  17. A shift in paradigm towards human biology-based systems for cholestatic-liver diseases.

    PubMed

    Noor, Fozia

    2015-12-01

    Cholestatic-liver diseases (CLDs) arise from diverse causes ranging from genetic factors to drug-induced cholestasis. The so-called diseases of civilization (obesity, diabetes, metabolic disorders, non-alcoholic liver disease, cardiovascular diseases, etc.) are intricately implicated in liver and gall bladder diseases. Although CLDs have been extensively studied, there seem to be important gaps in the understanding of human disease. Despite the fact that many animal models exist and substantial clinical data are available, translation of this knowledge towards therapy has been disappointingly limited. Recent advances in liver cell culture such as in vivo-like 3D cultivation of human primary hepatic cells, human induced pluripotent stem cell-derived hepatocytes; and cutting-edge analytical techniques such as 'omics' technologies and high-content screenings could play a decisive role in deeper mechanistic understanding of CLDs. This Topical Review proposes a roadmap to human biology-based research using omics technologies providing quantitative information on mechanisms in an adverse outcome/disease pathway framework. With modern sensitive tools, a shift in paradigm in human disease research seems timely and even inevitable to overcome species barriers in translation. PMID:26417843

  18. Theoretical study of chlordecone and surface groups interaction in an activated carbon model under acidic and neutral conditions.

    PubMed

    Gamboa-Carballo, Juan José; Melchor-Rodríguez, Kenia; Hernández-Valdés, Daniel; Enriquez-Victorero, Carlos; Montero-Alejo, Ana Lilian; Gaspard, Sarra; Jáuregui-Haza, Ulises Javier

    2016-04-01

    Activated carbons (ACs) are widely used in the purification of drinking water without almost any knowledge about the adsorption mechanisms of the persistent organic pollutants. Chlordecone (CLD, Kepone) is an organochlorinated synthetic compound that has been used mainly as agricultural insecticide. CLD has been identified and listed as a persistent organic pollutant by the Stockholm Convention. The selection of the best suited AC for this type of contaminants is mainly an empirical and costly process. A theoretical study of the influence of AC surface groups (SGs) on CLD adsorption is done in order to help understanding the process. This may provide a first selection criteria for the preparation of AC with suitable surface properties. A model of AC consisting of a seven membered ring graphene sheet (coronene) with a functional group on the edge was used to evaluate the influence of the SGs over the adsorption. Multiple Minima Hypersurface methodology (MMH) coupled with PM7 semiempirical Hamiltonian was employed in order to study the interactions of the chlordecone with SGs (hydroxyl and carboxyl) at acidic and neutral pH and different hydration conditions. Selected structures were re-optimized using CAM-B3LYP to achieve a well-defined electron density to characterize the interactions by the Quantum Theory of Atoms in Molecules approach. The deprotonated form of surface carboxyl and hydroxyl groups of AC models show the strongest interactions, suggesting a chemical adsorption. An increase in carboxylic SGs content is proposed to enhance CLD adsorption onto AC at neutral pH conditions. PMID:26945637

  19. Theoretical study of chlordecone and surface groups interaction in an activated carbon model under acidic and neutral conditions.

    PubMed

    Gamboa-Carballo, Juan José; Melchor-Rodríguez, Kenia; Hernández-Valdés, Daniel; Enriquez-Victorero, Carlos; Montero-Alejo, Ana Lilian; Gaspard, Sarra; Jáuregui-Haza, Ulises Javier

    2016-04-01

    Activated carbons (ACs) are widely used in the purification of drinking water without almost any knowledge about the adsorption mechanisms of the persistent organic pollutants. Chlordecone (CLD, Kepone) is an organochlorinated synthetic compound that has been used mainly as agricultural insecticide. CLD has been identified and listed as a persistent organic pollutant by the Stockholm Convention. The selection of the best suited AC for this type of contaminants is mainly an empirical and costly process. A theoretical study of the influence of AC surface groups (SGs) on CLD adsorption is done in order to help understanding the process. This may provide a first selection criteria for the preparation of AC with suitable surface properties. A model of AC consisting of a seven membered ring graphene sheet (coronene) with a functional group on the edge was used to evaluate the influence of the SGs over the adsorption. Multiple Minima Hypersurface methodology (MMH) coupled with PM7 semiempirical Hamiltonian was employed in order to study the interactions of the chlordecone with SGs (hydroxyl and carboxyl) at acidic and neutral pH and different hydration conditions. Selected structures were re-optimized using CAM-B3LYP to achieve a well-defined electron density to characterize the interactions by the Quantum Theory of Atoms in Molecules approach. The deprotonated form of surface carboxyl and hydroxyl groups of AC models show the strongest interactions, suggesting a chemical adsorption. An increase in carboxylic SGs content is proposed to enhance CLD adsorption onto AC at neutral pH conditions.

  20. Rearrangement of a common cellular DNA domain on chromosome 4 in human primary liver tumors

    SciTech Connect

    Pasquinelli, C.; Garreau, F.; Bougueleret, L.; Cariani, E.; Thiers, V.; Croissant, O.; Hadchouel, M.; Tiollais, P.; Brechot, C. ); Grzeschik, K.H. )

    1988-02-01

    Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. The authors have investigated whether common cellular DNA domains might be rearranged, possibly by HBV integration, in human primary liver tumors. Unique cellular DNA sequences adjacent to an HBV integration site were isolated from a patient with hepatitis B surface antigen-positive hepatocellular carcinoma. These probes detected rearrangement of this cellular region of chromosomal DNA in 3 of 50 additional primary liver tumors studied. Of these three tumor samples, two contained HBV DNA, without an apparent link between the viral DNA and the rearranged allele; HBV DNA sequences were not detected in the third tumor sample. By use of a panel of somatic cell hybrids, these unique cellular DNA sequences were shown to be located on chromosome 4. Therefore, this region of chromosomal DNA might be implicated in the formation of different tumors at one step of liver cell transformation, possible related to HBV integration.

  1. Prediction of Liver Injury Induced by Chemicals in Human With a Multiparametric Assay on Isolated Mouse Liver Mitochondria

    PubMed Central

    Porceddu, Mathieu; Buron, Nelly; Borgne-Sanchez, Annie

    2012-01-01

    Drug-induced liver injury (DILI) in humans is difficult to predict using classical in vitro cytotoxicity screening and regulatory animal studies. This explains why numerous compounds are stopped during clinical trials or withdrawn from the market due to hepatotoxicity. Thus, it is important to improve early prediction of DILI in human. In this study, we hypothesized that this goal could be achieved by investigating drug-induced mitochondrial dysfunction as this toxic effect is a major mechanism of DILI. To this end, we developed a high-throughput screening platform using isolated mouse liver mitochondria. Our broad spectrum multiparametric assay was designed to detect the global mitochondrial membrane permeabilization (swelling), inner membrane permeabilization (transmembrane potential), outer membrane permeabilization (cytochrome c release), and alteration of mitochondrial respiration driven by succinate or malate/glutamate. A pool of 124 chemicals (mainly drugs) was selected, including 87 with documented DILI and 37 without reported clinical hepatotoxicity. Our screening assay revealed an excellent sensitivity for clinical outcome of DILI (94 or 92% depending on cutoff) and a high positive predictive value (89 or 82%). A highly significant relationship between drug-induced mitochondrial toxicity and DILI occurrence in patients was calculated (p < 0.001). Moreover, this multiparametric assay allowed identifying several compounds for which mitochondrial toxicity had never been described before and even helped to clarify mechanisms with some drugs already known to be mitochondriotoxic. Investigation of drug-induced loss of mitochondrial integrity and function with this multiparametric assay should be considered for integration into basic screening processes at early stage to select drug candidates with lower risk of DILI in human. This assay is also a valuable tool for assessing the mitochondrial toxicity profile and investigating the mechanism of action of new

  2. Human Glucocorticoid Receptor β Regulates Gluconeogenesis and Inflammation in Mouse Liver

    PubMed Central

    He, Bo; Cruz-Topete, Diana; Oakley, Robert H.; Xiao, Xiao

    2015-01-01

    While in vitro studies have demonstrated that a glucocorticoid receptor (GR) splice isoform, β-isoform of human GR (hGRβ), acts as a dominant-negative inhibitor of the classic hGRα and confers glucocorticoid resistance, the in vivo function of hGRβ is poorly understood. To this end, we created an adeno-associated virus (AAV) to express hGRβ in the mouse liver under the control of the hepatocyte-specific promoter. Genome-wide expression analysis of mouse livers showed that hGRβ significantly increased the expression of numerous genes, many of which are involved in endocrine system disorders and the inflammatory response. Physiologically, hGRβ antagonized GRα's function and attenuated hepatic gluconeogenesis through downregulation of phosphoenolpyruvate carboxykinase (PEPCK) in wild-type (WT) mouse liver. Interestingly, however, hGRβ did not repress PEPCK in GR liver knockout (GRLKO) mice. In contrast, hGRβ regulates the expression of STAT1 in the livers of both WT and GRLKO mice. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays demonstrated that hGRβ binds to the intergenic glucocorticoid response element (GRE) of the STAT1 gene. Furthermore, treatment with RU486 inhibited the upregulation of STAT1 mediated by hGRβ. Finally, our array data demonstrate that hGRβ regulates unique components of liver gene expression in vivo by both GRα-dependent and GRα-independent mechanisms. PMID:26711253

  3. Open-Porous Hydroxyapatite Scaffolds for Three-Dimensional Culture of Human Adult Liver Cells

    PubMed Central

    Schmelzer, Eva; Over, Patrick; Nettleship, Ian; Gerlach, Joerg C.

    2016-01-01

    Liver cell culture within three-dimensional structures provides an improved culture system for various applications in basic research, pharmacological screening, and implantable or extracorporeal liver support. Biodegradable calcium-based scaffolds in such systems could enhance liver cell functionality by providing endothelial and hepatic cell support through locally elevated calcium levels, increased surface area for cell attachment, and allowing three-dimensional tissue restructuring. Open-porous hydroxyapatite scaffolds were fabricated and seeded with primary adult human liver cells, which were embedded within or without gels of extracellular matrix protein collagen-1 or hyaluronan. Metabolic functions were assessed after 5, 15, and 28 days. Longer-term cultures exhibited highest cell numbers and liver specific gene expression when cultured on hydroxyapatite scaffolds in collagen-1. Endothelial gene expression was induced in cells cultured on scaffolds without extracellular matrix proteins. Hydroxyapatite induced gene expression for cytokeratin-19 when cells were cultured in collagen-1 gel while culture in hyaluronan increased cytokeratin-19 gene expression independent of the use of scaffold in long-term culture. The implementation of hydroxyapatite composites with extracellular matrices affected liver cell cultures and cell differentiation depending on the type of matrix protein and the presence of a scaffold. The hydroxyapatite scaffolds enable scale-up of hepatic three-dimensional culture models for regenerative medicine applications. PMID:27403430

  4. Open-Porous Hydroxyapatite Scaffolds for Three-Dimensional Culture of Human Adult Liver Cells.

    PubMed

    Finoli, Anthony; Schmelzer, Eva; Over, Patrick; Nettleship, Ian; Gerlach, Joerg C

    2016-01-01

    Liver cell culture within three-dimensional structures provides an improved culture system for various applications in basic research, pharmacological screening, and implantable or extracorporeal liver support. Biodegradable calcium-based scaffolds in such systems could enhance liver cell functionality by providing endothelial and hepatic cell support through locally elevated calcium levels, increased surface area for cell attachment, and allowing three-dimensional tissue restructuring. Open-porous hydroxyapatite scaffolds were fabricated and seeded with primary adult human liver cells, which were embedded within or without gels of extracellular matrix protein collagen-1 or hyaluronan. Metabolic functions were assessed after 5, 15, and 28 days. Longer-term cultures exhibited highest cell numbers and liver specific gene expression when cultured on hydroxyapatite scaffolds in collagen-1. Endothelial gene expression was induced in cells cultured on scaffolds without extracellular matrix proteins. Hydroxyapatite induced gene expression for cytokeratin-19 when cells were cultured in collagen-1 gel while culture in hyaluronan increased cytokeratin-19 gene expression independent of the use of scaffold in long-term culture. The implementation of hydroxyapatite composites with extracellular matrices affected liver cell cultures and cell differentiation depending on the type of matrix protein and the presence of a scaffold. The hydroxyapatite scaffolds enable scale-up of hepatic three-dimensional culture models for regenerative medicine applications.

  5. Human carboxymethylenebutenolidase as a bioactivating hydrolase of olmesartan medoxomil in liver and intestine.

    PubMed

    Ishizuka, Tomoko; Fujimori, Izumi; Kato, Mitsunori; Noji-Sakikawa, Chisa; Saito, Motoko; Yoshigae, Yasushi; Kubota, Kazuishi; Kurihara, Atsushi; Izumi, Takashi; Ikeda, Toshihiko; Okazaki, Osamu

    2010-04-16

    Olmesartan medoxomil (OM) is a prodrug type angiotensin II type 1 receptor antagonist widely prescribed as an antihypertensive agent. Herein, we describe the identification and characterization of the OM bioactivating enzyme that hydrolyzes the prodrug and converts to its pharmacologically active metabolite olmesartan in human liver and intestine. The protein was purified from human liver cytosol by successive column chromatography and was identified by mass spectrometry to be a carboxymethylenebutenolidase (CMBL) homolog. Human CMBL, whose endogenous function has still not been reported, is a human homolog of Pseudomonas dienelactone hydrolase involved in the bacterial halocatechol degradation pathway. The ubiquitous expression of human CMBL gene transcript in various tissues was observed. The recombinant human CMBL expressed in mammalian cells was clearly shown to activate OM. By comparing the enzyme kinetics and chemical inhibition properties between the recombinant protein and human tissue preparations, CMBL was demonstrated to be the primary OM bioactivating enzyme in the liver and intestine. The recombinant CMBL also converted other prodrugs having the same ester structure as OM, faropenem medoxomil and lenampicillin, to their active metabolites. CMBL exhibited a unique sensitivity to chemical inhibitors, thus, being distinguishable from other known esterases. Site-directed mutagenesis on the putative active residue Cys(132) of the recombinant CMBL caused a drastic reduction of the OM-hydrolyzing activity. We report for the first time that CMBL serves as a key enzyme in the bioactivation of OM, hydrolyzing the ester bond of the prodrug type xenobiotics. PMID:20177059

  6. Human Carboxymethylenebutenolidase as a Bioactivating Hydrolase of Olmesartan Medoxomil in Liver and Intestine

    PubMed Central

    Ishizuka, Tomoko; Fujimori, Izumi; Kato, Mitsunori; Noji-Sakikawa, Chisa; Saito, Motoko; Yoshigae, Yasushi; Kubota, Kazuishi; Kurihara, Atsushi; Izumi, Takashi; Ikeda, Toshihiko; Okazaki, Osamu

    2010-01-01

    Olmesartan medoxomil (OM) is a prodrug type angiotensin II type 1 receptor antagonist widely prescribed as an antihypertensive agent. Herein, we describe the identification and characterization of the OM bioactivating enzyme that hydrolyzes the prodrug and converts to its pharmacologically active metabolite olmesartan in human liver and intestine. The protein was purified from human liver cytosol by successive column chromatography and was identified by mass spectrometry to be a carboxymethylenebutenolidase (CMBL) homolog. Human CMBL, whose endogenous function has still not been reported, is a human homolog of Pseudomonas dienelactone hydrolase involved in the bacterial halocatechol degradation pathway. The ubiquitous expression of human CMBL gene transcript in various tissues was observed. The recombinant human CMBL expressed in mammalian cells was clearly shown to activate OM. By comparing the enzyme kinetics and chemical inhibition properties between the recombinant protein and human tissue preparations, CMBL was demonstrated to be the primary OM bioactivating enzyme in the liver and intestine. The recombinant CMBL also converted other prodrugs having the same ester structure as OM, faropenem medoxomil and lenampicillin, to their active metabolites. CMBL exhibited a unique sensitivity to chemical inhibitors, thus, being distinguishable from other known esterases. Site-directed mutagenesis on the putative active residue Cys132 of the recombinant CMBL caused a drastic reduction of the OM-hydrolyzing activity. We report for the first time that CMBL serves as a key enzyme in the bioactivation of OM, hydrolyzing the ester bond of the prodrug type xenobiotics. PMID:20177059

  7. KINETICS OF BROMODICHLOROMETHANE METABOLISM BY CYTOCHROME P450 ISOENZYMES IN HUMAN LIVER MICROSOMES

    EPA Science Inventory

    Kinetics of Bromodichloromethane Metabolism by
    Cytochrome P450 Isoenzymes in Human Liver Microsomes

    Guangyu Zhao and John W. Allis

    ABSTRACT
    The kinetic constants for the metabolism of bromodichloromethane (BDCM) by three cytochrome P450 (CYP) isoenzymes have ...

  8. METABOLISM OF MYCLOBUTANIL AND TRIADIMEFON BY HUMAN AND RAT CYTOCHROME P450 ENZYMES AND LIVER MICROSOMES.

    EPA Science Inventory

    Metabolism of two triazole-containing antifungal azoles was studied using expressed human and rat cytochrome P450s (CYP) and liver microsomes. Substrate depletion methods were used due to the complex array of metabolites produced from myclobutanil and triadimefon. Myclobutanil wa...

  9. [Investigation of redox homeostasis of liver in experimental and human studies].

    PubMed

    Hagymási, Krisztina; Blázovics, Anna; Lengyel, Gabriella; Lugasi, Andrea; Fehér, János

    2004-01-01

    Great importance has been attributed to antioxidants in the treatment of conditions associated with oxidative stress for many years. At the same time the antioxidants can exert prooxidant activity. Combined antioxidant treatment is more favourable compared with monotherapy, because antioxidants have scavenger-, compartment- and tissue-specificity and they regenerate each other directly, too. Drugs of chronic liver diseases should be considered because of the role of liver in biotransformation. Our aim was to study the redox status of liver and investigate the effects of natural antioxidants (vegetable lyophilizates, silymarin, metadoxine) on liver redox status. Besides of clinical diagnosis, biochemical, analytical, histological methods were used to assess the free radical-antioxidant balance on the whole. Our in vitro methodological system is suitable for screening natural compounds for primary and secondary antioxidant property as well as membrane-stabilizing activity. A shift in free radical-antioxidant balance was proved in short-term extrahepatic cholestasis, antioxidant-type choleretic compounds can be investigated in this animal model. In human experiments redox status was investigated in the Gilbert's disease and in the most frequent chronic liver disorder in Hungary, in alcoholic liver disease. The improvement of non-enzymatic antioxidant defence system was found in Gilbert's disease without the alteration of free radical-antioxidant balance. Our results proved the role of free radical reactions in alcoholic liver disease and underlined the greater women vulnerability to alcohol toxicity. The chemiluminometric measurements in erythrocytes is suitable for the estimation of progression of alcoholic liver disease and of efficacy of antioxidant therapy. PMID:15524049

  10. Attempt to rescue discarded human liver grafts by end ischemic hypothermic oxygenated machine perfusion.

    PubMed

    Vekemans, K; van Pelt, J; Komuta, M; Wylin, T; Heedfeld, V; Detry, O; Monbaliu, D; Pirenne, J

    2011-11-01

    In a porcine liver transplant model, a brief period of oxygenated hypothermic machine perfusion (HMP) at the end of simple cold storage (SCS) has been shown to improve the viability of damaged liver grafts. To test the clinical validity of this strategy, we randomized SCS-discarded human liver grafts to either 4 hours of HMP (n = 13) or an additional 4 hours of SCS (n = 14). All livers were then warm reperfused to mimic ischemia-reperfusion injury ex vivo. The settings for HMP were: portal vein: 3 mm Hg, 300 mL/min and hepatic artery: 20 mm Hg, pO(2): 300 mm Hg. Perfusion used Kidney Machine Perfusion Solution at 4°C to 8°C. During warm reperfusion, aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) values were higher (P < .015) among the SCS versus HMP methods at all times. The AST slope was lower in HMP versus SCS (P = .01). The LDH slope tended to be lower for HMP versus SCS (P = .07). Morphological scores were not different between HMP and SCS. At the start of warm reperfusion, MAPK was lower in HMP versus SCS (P = .02). Endothelin-1 (EDN1) and ICAM-1 tended to be lower in HMP versus SCS (P = .1 and .07, respectively). No difference was noted in MAPK, EDN1, and ICAM-1 after 60 or 120 minutes of warm reperfusion. In conclusion, HMP down-regulated MAPK and tended to reduce EDN1 and ICAM-1 mRNA in human liver grafts. During warm reperfusion, HMP versus SCS livers showed reduced AST and LDH release but no morphological difference. Further optimization of liver HMP may require different timing/duration of perfusion and/or an higher perfusion temperature.

  11. Differences in Redox Regulatory Systems in Human Lung and Liver Tumors Suggest Different Avenues for Therapy

    PubMed Central

    Tobe, Ryuta; Carlson, Bradley A.; Tsuji, Petra A.; Lee, Byeong Jae; Gladyshev, Vadim N.; Hatfield, Dolph L.

    2015-01-01

    A common characteristic of many cancer cells is that they suffer from oxidative stress. They, therefore, require effective redox regulatory systems to combat the higher levels of reactive oxygen species that accompany accelerated growth compared to the normal cells of origin. An elevated dependence on these systems in cancers suggests that targeting these systems may provide an avenue for retarding the malignancy process. Herein, we examined the redox regulatory systems in human liver and lung cancers by comparing human lung adenocarcinoma and liver carcinoma to their respective surrounding normal tissues. Significant differences were found in the two major redox systems, the thioredoxin and glutathione systems. Thioredoxin reductase 1 levels were elevated in both malignancies, but thioredoxin was highly upregulated in lung tumor and only slightly upregulated in liver tumor, while peroxiredoxin 1 was highly elevated in lung tumor, but downregulated in liver tumor. There were also major differences within the glutathione system between the malignancies and their normal tissues. The data suggest a greater dependence of liver on either the thioredoxin or glutathione system to drive the malignancy, while lung cancer appeared to depend primarily on the thioredoxin system. PMID:26569310

  12. Metabolomic profiling can predict which humans will develop liver dysfunction when deprived of dietary choline

    PubMed Central

    Sha, Wei; da Costa, Kerry-Ann; Fischer, Leslie M.; Milburn, Michael V.; Lawton, Kay A.; Berger, Alvin; Jia, Wei; Zeisel, Steven H.

    2010-01-01

    Choline is an essential nutrient, and deficiency causes liver and muscle dysfunction. Common genetic variations alter the risk of developing organ dysfunction when choline deficient, probably by causing metabolic inefficiencies that should be detectable even while ingesting a normal choline-adequate diet. We determined whether metabolomic profiling of plasma at baseline could predict whether humans will develop liver dysfunction when deprived of dietary choline. Fifty-three participants were fed a diet containing 550 mg choline/70 kg/d for 10 d and then fed <50 mg choline/70 kg/d for up to 42 d. Participants who developed organ dysfunction on this diet were repleted with a choline-adequate diet for ≥3 d. Plasma samples, obtained at baseline, end of depletion, and end of repletion, were used for targeted and nontargeted metabolomic profiling. Liver fat was assessed using magnetic resonance spectroscopy. Metabolomic profiling and targeted biochemical analyses were highly correlated for the analytes assessed by both procedures. In addition, we report relative concentration changes of other small molecules detected by the nontargeted metabolomic analysis after choline depletion. Finally, we show that metabolomic profiles of participants when they were consuming a control baseline diet could predict whether they would develop liver dysfunction when deprived of dietary choline.—Sha, W., da Costa, K., Fischer, L. M., Milburn, M. V., Lawton, K. A., Berger, A., Jia, W., Zeisel, S. H. Metabolomic profiling can predict which humans will develop liver dysfunction when deprived of dietary choline. PMID:20371621

  13. The draft genome of the carcinogenic human liver fluke Clonorchis sinensis

    PubMed Central

    2011-01-01

    Background Clonorchis sinensis is a carcinogenic human liver fluke that is widespread in Asian countries. Increasing infection rates of this neglected tropical disease are leading to negative economic and public health consequences in affected regions. Experimental and epidemiological studies have shown a strong association between the incidence of cholangiocarcinoma and the infection rate of C. sinensis. To aid research into this organism, we have sequenced its genome. Results We combined de novo sequencing with computational techniques to provide new information about the biology of this liver fluke. The assembled genome has a total size of 516 Mb with a scaffold N50 length of 42 kb. Approximately 16,000 reliable protein-coding gene models were predicted. Genes for the complete pathways for glycolysis, the Krebs cycle and fatty acid metabolism were found, but key genes involved in fatty acid biosynthesis are missing from the genome, reflecting the parasitic lifestyle of a liver fluke that receives lipids from the bile of its host. We also identified pathogenic molecules that may contribute to liver fluke-induced hepatobiliary diseases. Large proteins such as multifunctional secreted proteases and tegumental proteins were identified as potential targets for the development of drugs and vaccines. Conclusions This study provides valuable genomic information about the human liver fluke C. sinensis and adds to our knowledge on the biology of the parasite. The draft genome will serve as a platform to develop new strategies for parasite control. PMID:22023798

  14. Induction of three-dimensional assembly of human liver cells by simulated microgravity

    NASA Technical Reports Server (NTRS)

    Khaoustov, V. I.; Darlington, G. J.; Soriano, H. E.; Krishnan, B.; Risin, D.; Pellis, N. R.; Yoffe, B.

    1999-01-01

    The establishment of long-term cultures of functional primary human liver cells (PHLC) is formidable. Developed at NASA, the Rotary Cell Culture System (RCCS) allows the creation of the unique microgravity environment of low shear force, high-mass transfer, and 3-dimensional cell culture of dissimilar cell types. The aim of our study was to establish long-term hepatocyte cultures in simulated microgravity. PHLC were harvested from human livers by collagenase perfusion and were cultured in RCCS. PHLC aggregates were readily formed and increased up to 1 cm long. The expansion of PHLC in bioreactors was further evaluated with microcarriers and biodegradable scaffolds. While microcarriers were not conducive to formation of spheroids, PHLC cultured with biodegradable scaffolds formed aggregates up to 3 cm long. Analyses of PHLC spheroids revealed tissue-like structures composed of hepatocytes, biliary epithelial cells, and/or progenitor liver cells that were arranged as bile duct-like structures along nascent vascular sprouts. Electron microscopy revealed groups of cohesive hepatocytes surrounded by complex stromal structures and reticulin fibers, bile canaliculi with multiple microvilli, and tight cellular junctions. Albumin mRNA was expressed throughout the 60-d culture. A simulated microgravity environment is conducive to maintaining long-term cultures of functional hepatocytes. This model system will assist in developing improved protocols for autologous hepatocyte transplantation, gene therapy, and liver assist devices, and facilitate studies of liver regeneration and cell-to-cell interactions that occur in vivo.

  15. Ex vivo normothermic machine perfusion and viability testing of discarded human donor livers.

    PubMed

    op den Dries, S; Karimian, N; Sutton, M E; Westerkamp, A C; Nijsten, M W N; Gouw, A S H; Wiersema-Buist, J; Lisman, T; Leuvenink, H G D; Porte, R J

    2013-05-01

    In contrast to traditional static cold preservation of donor livers, normothermic machine perfusion may reduce preservation injury, improve graft viability and potentially allows ex vivo assessment of graft viability before transplantation. We have studied the feasibility of normothermic machine perfusion in four discarded human donor livers. Normothermic machine perfusion consisted of pressure and temperature controlled pulsatile perfusion of the hepatic artery and continuous portal perfusion for 6 h. Two hollow fiber membrane oxygenators provided oxygenation of the perfusion fluid. Biochemical markers in the perfusion fluid reflected minimal hepatic injury and improving function. Lactate levels decreased to normal values, reflecting active metabolism by the liver (mean lactate 10.0 ± 2.3 mmol/L at 30 min to 2.3 ± 1.2 mmol/L at 6 h). Bile production was observed throughout the 6 h perfusion period (mean rate 8.16 ± 0.65 g/h after the first hour). Histological examination before and after 6 h of perfusion showed well-preserved liver morphology without signs of additional hepatocellular ischemia, biliary injury or sinusoidal damage. In conclusion, this study shows that normothermic machine perfusion of human donor livers is technically feasible. It allows assessment of graft viability before transplantation, which opens new avenues for organ selection, therapeutic interventions and preconditioning.

  16. The CYP2A3 gene product catalyzes coumarin 7-hydroxylation in human liver microsomes

    SciTech Connect

    Yamano, Shigeru; Tatsuno, Jun; Gonzalez, F.J. )

    1990-02-06

    Three cDNAs, designated IIA3, IIA3v, and IIA4, coding for P450s in the CYP2A gene subfamily were isolated from a {lambda}gt11 library prepared from human hepatic mRNA. Only three nucleotide differences and a single amino acid difference, Leu{sup 160}{yields}His, were found between IIA3 and IIA3v, indicating that they are probably allelic variants. IIA4 displayed 94% amino acid similarity with IIA3 and IIA3v. The three cDNAs were inserted into vaccinia virus, and recombinant viruses were used to infect human hepatoma Hep G2 cells. Only IIA3 was able to produce an enzyme that had a reduced CO-bound spectrum with a {lambda}{sub max} at 450 nm. This expressed enzyme was able to carry out coumarin 7-hydroxylation and ethoxycoumarin O-deethylation. cDNA-expressed IIA3v and IIA4 failed to incorporate heme and were enzymatically inactive. Analysis of IIA proteins in human liver microsomes, using antibody against rat IIA2, revealed two proteins of 49 and 50 kDa, the former of which appeared to correlate with human microsomal coumarin 7-hydroxylase activity. A more striking correlation was found between IIa mRNA and enzyme activity. The rat antibody was able to completely abolish coumarin 7-hydroxylase activity in 12 liver samples. These data establish that the CYP2A3 gene product is primarily responsible for coumarin 7-hydroxylase activity in human liver. The level of expression of this activity varied up to 40-fold between livers. Levels of IIA mRNA also varied significantly between liver specimens, and three specimens had no detectable mRNA.

  17. Alcohol Increases Liver Progenitor Populations and Induces Disease Phenotypes in Human IPSC-Derived Mature Stage Hepatic Cells.

    PubMed

    Tian, Lipeng; Deshmukh, Abhijeet; Prasad, Neha; Jang, Yoon-Young

    2016-01-01

    Alcohol consumption has long been a global problem affecting human health, and has been found to influence both fetal and adult liver functions. However, how alcohol affects human liver development and liver progenitor cells remains largely unknown. Here, we used human induced pluripotent stem cells (iPSCs) as a model to examine the effects of alcohol, on multi-stage hepatic cells including hepatic progenitors, early and mature hepatocyte-like cells derived from human iPSCs. While alcohol has little effect on endoderm development from iPSCs, it reduces formation of hepatic progenitor cells during early hepatic specification. The proliferative activities of early and mature hepatocyte-like cells are significantly decreased after alcohol exposure. Importantly, at a mature stage of hepatocyte-like cells, alcohol treatment increases two liver progenitor subsets, causes oxidative mitochondrial injury and results in liver disease phenotypes (i.e., steatosis and hepatocellular carcinoma associated markers) in a dose dependent manner. Some of the phenotypes were significantly improved by antioxidant treatment. This report suggests that fetal alcohol exposure may impair generation of hepatic progenitors at early stage of hepatic specification and decrease proliferation of fetal hepatocytes; meanwhile alcohol injury in post-natal or mature stage human liver may contribute to disease phenotypes. This human iPSC model of alcohol-induced liver injury can be highly valuable for investigating alcoholic injury in the fetus as well as understanding the pathogenesis and ultimately developing effective treatment for alcoholic liver disease in adults. PMID:27570479

  18. Alcohol Increases Liver Progenitor Populations and Induces Disease Phenotypes in Human IPSC-Derived Mature Stage Hepatic Cells

    PubMed Central

    Tian, Lipeng; Deshmukh, Abhijeet; Prasad, Neha; Jang, Yoon-Young

    2016-01-01

    Alcohol consumption has long been a global problem affecting human health, and has been found to influence both fetal and adult liver functions. However, how alcohol affects human liver development and liver progenitor cells remains largely unknown. Here, we used human induced pluripotent stem cells (iPSCs) as a model to examine the effects of alcohol, on multi-stage hepatic cells including hepatic progenitors, early and mature hepatocyte-like cells derived from human iPSCs. While alcohol has little effect on endoderm development from iPSCs, it reduces formation of hepatic progenitor cells during early hepatic specification. The proliferative activities of early and mature hepatocyte-like cells are significantly decreased after alcohol exposure. Importantly, at a mature stage of hepatocyte-like cells, alcohol treatment increases two liver progenitor subsets, causes oxidative mitochondrial injury and results in liver disease phenotypes (i.e., steatosis and hepatocellular carcinoma associated markers) in a dose dependent manner. Some of the phenotypes were significantly improved by antioxidant treatment. This report suggests that fetal alcohol exposure may impair generation of hepatic progenitors at early stage of hepatic specification and decrease proliferation of fetal hepatocytes; meanwhile alcohol injury in post-natal or mature stage human liver may contribute to disease phenotypes. This human iPSC model of alcohol-induced liver injury can be highly valuable for investigating alcoholic injury in the fetus as well as understanding the pathogenesis and ultimately developing effective treatment for alcoholic liver disease in adults. PMID:27570479

  19. In vitro Phase I and Phase II metabolism of α-pyrrolidinovalerophenone (α-PVP), methylenedioxypyrovalerone (MDPV) and methedrone by human liver microsomes and human liver cytosol.

    PubMed

    Negreira, Noelia; Erratico, Claudio; Kosjek, Tina; van Nuijs, Alexander L N; Heath, Ester; Neels, Hugo; Covaci, Adrian

    2015-07-01

    The aim of the present study was to identify the in vitro Phase I and Phase II metabolites of three new psychoactive substances: α-pyrrolidinovalerophenone (α-PVP), methylenedioxypyrovalerone (MDPV), and methedrone, using human liver microsomes and human liver cytosol. Accurate-mass spectra of metabolites were obtained using liquid chromatography-quadrupole time-of-flight mass spectrometry. Six Phase I metabolites of α-PVP were identified, which were formed involving reduction, hydroxylation, and pyrrolidine ring opening reactions. The lactam compound was the major metabolite observed for α-PVP. Two glucuronidated metabolites of α-PVP, not reported in previous in vitro studies, were further identified. MDPV was transformed into 10 Phase I metabolites involving reduction, hydroxylation, and loss of the pyrrolidine ring. Also, six glucuronidated and two sulphated metabolites were detected. The major metabolite of MDPV was the catechol metabolite. Methedrone was transformed into five Phase I metabolites, involving N- and O-demethylation, hydroxylation, and reduction of the ketone group. Three metabolites of methedrone are reported for the first time. In addition, the contribution of individual human CYP enzymes in the formation of the detected metabolites was investigated. PMID:26014283

  20. Comparative metabolism of chloroacetamide herbicides and selected metabolites in human and rat liver microsomes.

    PubMed Central

    Coleman, S; Linderman, R; Hodgson, E; Rose, R L

    2000-01-01

    Acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methyl-phenyl)-acetamide], alachlor [N-(methoxymethyl)-2-chloro-N-(2, 6-diethyl-phenyl)acetamide], butachlor [N-(butoxymethyl)-2-chloro-N-(2,6-diethyl-phenyl)acetamide], and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide] are pre-emergent herbicides used in the production of agricultural crops. These herbicides are carcinogenic in rats: acetochlor and alachlor cause tumors in the nasal turbinates, butachlor causes stomach tumors, and metolachlor causes liver tumors. It has been suggested that the carcinogenicity of these compounds involves a complex metabolic activation pathway leading to a DNA-reactive dialkylbenzoquinone imine. Important intermediates in this pathway are 2-chloro-N-(2,6-diethylphenyl)acetamide (CDEPA) produced from alachlor and butachlor and 2-chloro-N-(2-methyl-6-ethylphenyl)acetamide (CMEPA) produced from acetochlor and metolachlor. Subsequent metabolism of CDEPA and CMEPA produces 2,6-diethylaniline (DEA) and 2-methyl-6-ethylaniline (MEA), which are bioactivated through para-hydroxylation and subsequent oxidation to the proposed carcinogenic product dialkylbenzoquinone imine. The current study extends our earlier studies with alachlor and demonstrates that rat liver microsomes metabolize acetochlor and metolachlor to CMEPA (0.065 nmol/min/mg and 0.0133 nmol/min/mg, respectively), whereas human liver microsomes can metabolize only acetochlor to CMEPA (0.023 nmol/min/mg). Butachlor is metabolized to CDEPA to a much greater extent by rat liver microsomes (0.045 nmol/min/mg) than by human liver microsomes (< 0.001 nmol/min/mg). We have determined that both rat and human livers metabolize both CMEPA to MEA (0.308 nmol/min/mg and 0.541 nmol/min/mg, respectively) and CDEPA to DEA (0.350 nmol/min/mg and 0.841 nmol/min/mg, respectively). We have shown that both rat and human liver microsomes metabolize MEA (0.035 nmol/min/mg and 0.069 nmol/min/mg, respectively

  1. Amebic liver abscess and human immunodeficiency virus infection: a report of three cases.

    PubMed

    Liu, C J; Hung, C C; Chen, M Y; Lai, Y P; Chen, P J; Huang, S H; Chen, D S

    2001-07-01

    Invasive amebiasis rarely occurs in homosexual men and human immunodeficiency virus (HIV)-infected individuals and has not been regarded as a beacon for concomitant HIV infection. We encountered a bisexual man with a protracted course of amebic liver abscess and amebic colitis. In the presence of fever, generalized lymphadenopathy, and elevated serum aminotransferase levels, HIV infection was suspected and then confirmed by a de novo seroconversion of HIV antibody. Subsequently, we noted two consecutive patients with amebic liver abscess, also later found to be infected with HIV. The ameba obtained from these three cases was identified as Entamoeba histolytica by amplification of 16S ribosomal RNA by polymerase chain reaction and direct sequencing. This observation suggests that amebic liver abscess and colitis can be presentations for HIV infection in the Far East. Thus, the local patients with invasive amebiasis, especially those with a protracted course or with risk factors of HIV infection, should be tested for HIV.

  2. Monocyte-induced recovery of inflammation-associated hepatocellular dysfunction in a biochip-based human liver model.

    PubMed

    Gröger, Marko; Rennert, Knut; Giszas, Benjamin; Weiß, Elisabeth; Dinger, Julia; Funke, Harald; Kiehntopf, Michael; Peters, Frank T; Lupp, Amelie; Bauer, Michael; Claus, Ralf A; Huber, Otmar; Mosig, Alexander S

    2016-02-23

    Liver dysfunction is an early event in sepsis-related multi-organ failure. We here report the establishment and characterization of a microfluidically supported in vitro organoid model of the human liver sinusoid. The liver organoid is composed of vascular and hepatocyte cell layers integrating non-parenchymal cells closely reflecting tissue architecture and enables physiological cross-communication in a bio-inspired fashion. Inflammation-associated liver dysfunction was mimicked by stimulation with various agonists of toll-like receptors. TLR-stimulation induced the release of pro- and anti-inflammatory cytokines and diminished expression of endothelial VE-cadherin, hepatic MRP-2 transporter and apolipoprotein B (ApoB), resulting in an inflammation-related endothelial barrier disruption and hepatocellular dysfunction in the liver organoid. However, interaction of the liver organoid with human monocytes attenuated inflammation-related cell responses and restored MRP-2 transporter activity, ApoB expression and albumin/urea production. The cellular events observed in the liver organoid closely resembled pathophysiological responses in the well-established sepsis model of peritoneal contamination and infection (PCI) in mice and clinical observations in human sepsis. We therefore conclude that this human liver organoid model is a valuable tool to investigate sepsis-related liver dysfunction and subsequent immune cell-related tissue repair/remodeling processes.

  3. Monocyte-induced recovery of inflammation-associated hepatocellular dysfunction in a biochip-based human liver model

    PubMed Central

    Gröger, Marko; Rennert, Knut; Giszas, Benjamin; Weiß, Elisabeth; Dinger, Julia; Funke, Harald; Kiehntopf, Michael; Peters, Frank T.; Lupp, Amelie; Bauer, Michael; Claus, Ralf A.; Huber, Otmar; Mosig, Alexander S.

    2016-01-01

    Liver dysfunction is an early event in sepsis-related multi-organ failure. We here report the establishment and characterization of a microfluidically supported in vitro organoid model of the human liver sinusoid. The liver organoid is composed of vascular and hepatocyte cell layers integrating non-parenchymal cells closely reflecting tissue architecture and enables physiological cross-communication in a bio-inspired fashion. Inflammation-associated liver dysfunction was mimicked by stimulation with various agonists of toll-like receptors. TLR-stimulation induced the release of pro- and anti-inflammatory cytokines and diminished expression of endothelial VE-cadherin, hepatic MRP-2 transporter and apolipoprotein B (ApoB), resulting in an inflammation-related endothelial barrier disruption and hepatocellular dysfunction in the liver organoid. However, interaction of the liver organoid with human monocytes attenuated inflammation-related cell responses and restored MRP-2 transporter activity, ApoB expression and albumin/urea production. The cellular events observed in the liver organoid closely resembled pathophysiological responses in the well-established sepsis model of peritoneal contamination and infection (PCI) in mice and clinical observations in human sepsis. We therefore conclude that this human liver organoid model is a valuable tool to investigate sepsis-related liver dysfunction and subsequent immune cell-related tissue repair/remodeling processes. PMID:26902749

  4. Cytotoxicity of gold nanoclusters in human liver cancer cells

    PubMed Central

    Yang, Yanjie; Nan, Jing; Hou, Jianwen; Yu, Bianfei; Zhao, Tong; Xu, Shuang; Lv, Shuangyu; Zhang, Haixia

    2014-01-01

    In this study, we synthesized water-soluble fluorescent gold nanoclusters (Au NCs) stabilized with dihydrolipoic acid (DHLA). The cytotoxicity of these Au NCs was then assessed in the normal human hepatic cell line (L02) and the human hepatoma cell line (HepG2) at different exposure times. Cell viability was normal in both cell lines at 24 hours and 48 hours; however, the growth of HepG2 cells was significantly inhibited at 72 hours. The change in lactate dehydrogenase level was strongly correlated with cell viability after 72 hours incubation with DHLA–capped Au NCs, and the increase in cellular reactive oxygen species may be related to the decrease in cell viability. Growth inhibition of HepG2 cells was possibly due to difficultly passing the checkpoint between G1 phase and S phase. The anticancer activity of DHLA–capped Au NCs should be considered when used in biomedical imaging and drug delivery. PMID:25473282

  5. Cytotoxicity of gold nanoclusters in human liver cancer cells.

    PubMed

    Yang, Yanjie; Nan, Jing; Hou, Jianwen; Yu, Bianfei; Zhao, Tong; Xu, Shuang; Lv, Shuangyu; Zhang, Haixia

    2014-01-01

    In this study, we synthesized water-soluble fluorescent gold nanoclusters (Au NCs) stabilized with dihydrolipoic acid (DHLA). The cytotoxicity of these Au NCs was then assessed in the normal human hepatic cell line (L02) and the human hepatoma cell line (HepG2) at different exposure times. Cell viability was normal in both cell lines at 24 hours and 48 hours; however, the growth of HepG2 cells was significantly inhibited at 72 hours. The change in lactate dehydrogenase level was strongly correlated with cell viability after 72 hours incubation with DHLA-capped Au NCs, and the increase in cellular reactive oxygen species may be related to the decrease in cell viability. Growth inhibition of HepG2 cells was possibly due to difficultly passing the checkpoint between G1 phase and S phase. The anticancer activity of DHLA-capped Au NCs should be considered when used in biomedical imaging and drug delivery.

  6. The tyrosine kinase inhibitor nilotinib selectively inhibits CYP2C8 activities in human liver microsomes.

    PubMed

    Kim, Min-Jung; Lee, Jae-Won; Oh, Kyung-Suk; Choi, Chang-Soo; Kim, Kwang Hee; Han, Won Seok; Yoon, Chang-No; Chung, Eun Sook; Kim, Dong-Hyun; Shin, Jae-Gook

    2013-01-01

    The tyrosine kinase inhibitor nilotinib was examined for its inhibition of cytochrome P450s (CYPs) in human liver microsomes and in human CYPs expressed in a baculovirus-insect cell system. Nilotinib demonstrated preferential inhibition of CYP2C8-mediated paclitaxel 6α-hydroxylation, rosiglitazone hydroxylation and amodiaquine N-deethylation in human liver microsomes, with IC₅₀ values of 0.4, 7.5 and 0.7 µM, respectively. The IC₅₀ value of nilotinib for paclitaxel 6α-hydroxylation was 20-fold lower than that of the other five tyrosine-kinase inhibitors tested. Nilotinib appears to display competitive inhibition against paclitaxel 6α-hydroxylation and amodiaquine N-deethylation, with estimated mean Ki values of 0.90 and 0.15 µM in human liver microsomes and 0.10 and 0.61 µM in recombinant human CYP2C8, respectively. These results are consistent with those of molecular docking simulations, where paclitaxel could not access the CYP2C8 catalytic site in the presence of nilotinib, but the binding of midazolam, a substrate of CYP3A4, to the catalytic site of CYP3A4 was not affected by nilotinib. The demonstrated inhibitory activity of nilotinib against CYP2C8 at concentrations less than those observed in patients who received nilotinib therapy is of potential clinical relevance and further in vivo exploration is warranted.

  7. [Interaction of butylphthalide with rat and human liver CYP450 isoenzymes].

    PubMed

    Zhao, Qian; Hu, Jin-ping; Jiang, Ji; Li, Yan; Hu, Pei

    2015-05-01

    The work aims to study the drug metabolizing enzymes involved in the metabolism of butylphthalide and evaluate the induction and inhibition activities of butylphthalide on CYP450 isoenzymes by using in vitro (liver microsome incubation system of rats and human) and in vivo (CYP induced model of rats) method. Butylphthalide was incubated with selective inhibitors of CYP450, and its metabolic rate was determined to identify the metabolizing isoenzymes of NBP in rat (normal and induced rats) and human liver microsomes. The in vitro inhibition effect of butylphthalide on 6 main liver microsomal CYP450 isoenzymes was evaluated by using probe drugs; the induction and inhibition activities in vivo of butylphthalide on CYP450 isoenzymes were evaluated by NBP ig dosing (160 mg x kg(-1)) and iv dosing (20 mg x kg(-1)) in rats. After adding the specific inhibitors of CYP2C11, 2E1 and 3A 1/2 for rat, CYP2C19, 2E1 and 3A4/5 for human, the metabolism of NBP in rat and human liver microsomes were reduced 38.8%, 86.2%, 78.4% and 51.0%, 92.0%, 58.9% of control, respectively. The metabolic rates of NBP in CYP2E1 and 3A 1/2 induced rat liver microsomes were increased 25.5% and 68.9%. High concentration of NBP (≥ 200 μmol x L(-1), in vitro) could inhibit the activities of CYP1A2, 2C6, 2C11 and 2D2 in rats, and high concentration of NBP ( ≥ 15 μmol x L(-1), in vitro) could inhibit the activity of CYP2C19 in human. All the results indicated that NBP should be mainly metabolized by CYP2E1, 2C11 and 3A 1/2 in rats and CYP2E1, 2C19 and 3A4/5 in human. High concentration of NBP could inhibit human CYP2C19 in vitro. No significant induction/inhibition effects of NBP were observed on rat liver CYP450 isoforms after ig 160 mg x kg(-1) NBP or iv 20 mg x kg(-1) NBP. PMID:26234133

  8. In vivo time-harmonic multifrequency elastography of the human liver

    NASA Astrophysics Data System (ADS)

    Tzschätzsch, Heiko; Ipek-Ugay, Selcan; Guo, Jing; Streitberger, Kaspar-Josche; Gentz, Enno; Fischer, Thomas; Klaua, Robert; Schultz, Michael; Braun, Jürgen; Sack, Ingolf

    2014-04-01

    Elastography is capable of noninvasively detecting hepatic fibrosis by imposing mechanical stress and measuring the viscoelastic response in the liver. Magnetic resonance elastography (MRE) relies on time-harmonic vibrations, while most dynamic ultrasound elastography methods employ transient stimulation methods. This study attempts to benefit from the advantages of time-harmonic tissue stimulation, i.e. relative insensitivity to obesity and ascites and mechanical approachability of the entire liver, and the advantages of ultrasound, i.e. time efficiency, low costs, and wide availability, by introducing in vivo time-harmonic elastography (THE) of the human liver using ultrasound and a broad range of harmonic stimulation frequencies. THE employs continuous harmonic shear vibrations at 7 frequencies from 30 to 60 Hz in a single examination and determines the elasticity and the viscosity of the liver from the dispersion of the shear wave speed within the applied frequency range. The feasibility of the method is demonstrated in the livers of eight healthy volunteers and a patient with cirrhosis. Multifrequency MRE at the same drive frequencies was used as elastographic reference method. Similar values of shear modulus and shear viscosity according the Kelvin-Voigt model were obtained by MRE and THE, indicating that the new method is suitable for in vivo quantification of the shear viscoelastic properties of the liver, however, in real-time and at a fraction of the costs of MRE. In conclusion, THE may provide a useful tool for fast assessment of the viscoelastic properties of the liver at low costs and without limitations in obesity, ascites or hemochromatosis.

  9. Influence of nanoparticles accumulation on optical properties of human normal and cancerous liver tissue in vitro estimated by OCT

    NASA Astrophysics Data System (ADS)

    Zhou, Fang; Wei, Huajiang; Ye, Xiangping; Hu, Kun; Wu, Guoyong; Yang, Hongqin; He, Yonghong; Xie, Shusen; Guo, Zhouyi

    2015-02-01

    In this work, the potential use of nanoparticles as contrast agents by using spectral domain optical coherence tomography (SD-OCT) in liver tissue was demonstrated. Gold nanoparticles (average size of 25 and 70 nm), were studied in human normal and cancerous liver tissues in vitro, respectively. Each sample was monitored with SD-OCT functional imaging for 240 min. Continuous OCT monitoring showed that, after application of gold nanoparticles, the OCT signal intensities of normal liver and cancerous liver tissue both increase with time, and the larger nanoparticles tend to produce a greater signal enhancement in the same type of tissue. The results show that the values of attenuation coefficients have significant differences between normal liver tissue and cancerous liver tissue. In addition, 25 nm gold nanoparticles allow higher penetration depth than 70 nm gold nanoparticles in liver tissues.

  10. Nicotine induces fibrogenic changes in human liver via nicotinic acetylcholine receptors expressed on hepatic stellate cells

    SciTech Connect

    Soeda, Junpei; Morgan, Maelle; McKee, Chad; Mouralidarane, Angelina; Lin, ChingI; Roskams, Tania; Oben, Jude A.

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Cigarette smoke may induce liver fibrosis via nicotine receptors. Black-Right-Pointing-Pointer Nicotine induces proliferation of hepatic stellate cells (HSCs). Black-Right-Pointing-Pointer Nicotine activates hepatic fibrogenic pathways. Black-Right-Pointing-Pointer Nicotine receptor antagonists attenuate HSC proliferation. Black-Right-Pointing-Pointer Nicotinic receptor antagonists may have utility as novel anti-fibrotic agents. -- Abstract: Background and aims: Cigarette smoke (CS) may cause liver fibrosis but possible involved mechanisms are unclear. Among the many chemicals in CS is nicotine - which affects cells through nicotinic acetylcholine receptors (nAChR). We studied the effects of nicotine, and involved pathways, on human primary hepatic stellate cells (hHSCs), the principal fibrogenic cells in the liver. We then determined possible disease relevance by assaying nAChR in liver samples from human non-alcoholic steatohepatitis (NASH). Methods: hHSC were isolated from healthy human livers and nAChR expression analyzed - RT-PCR and Western blotting. Nicotine induction of hHSC proliferation, upregulation of collagen1-{alpha}2 and the pro-fibrogenic cytokine transforming growth factor beta 1 (TGF-{beta}1) was determined along with involved intracellular signaling pathways. nAChR mRNA expression was finally analyzed in whole liver biopsies obtained from patients diagnosed with non-alcoholic steatohepatitis (NASH). Results: hHSCs express muscle type ({alpha}1, {beta}1, delta and epsilon) and neuronal type ({alpha}3, {alpha}6, {alpha}7, {beta}2 and {beta}4) nAChR subunits at the mRNA level. Among these subunits, {alpha}3, {alpha}7, {beta}1 and {epsilon} were predominantly expressed as confirmed by Western blotting. Nicotine induced hHSC proliferation was attenuated by mecamylamine (p < 0.05). Additionally, collagen1-{alpha}2 and TGF-{beta}1 mRNA expression were significantly upregulated by nicotine and inhibited by

  11. Proteomic Profiling of Human Liver Biopsies: Hepatitis C Virus-Induced Fibrosis and Mitochondrial Dysfunction

    SciTech Connect

    Diamond, Deborah L.; Jacobs, Jon M.; Paeper, Bryan; Proll, Sean; Gritsenko, Marina A.; Carithers, Jr., Robert L.; Larson , Anne M.; Yeh, Matthew M.; Camp, David G.; Smith, Richard D.; Katze, Michael G.

    2007-09-01

    Liver biopsies from HCV-infected patients offer the unique opportunity to study human liver biology and disease in vivo. However, the low protein yields associated with these small samples present a significant challenge for proteomic analysis. In this study we describe the application of an ultra-sensitive proteomics platform for performing robust quantitative proteomic studies on microgram amounts of HCV-infected human liver tissue from 15 patients at different stages of fibrosis. A high quality liver protein data base containing 5,920 unique protein identifications supported high throughput quantitative studies using 16O:18O stable isotope labeling in combination with the accurate mass and time (AMT) tag approach. A total of 1,641 liver biopsy proteins were quantified and ANOVA identified 210 proteins exhibiting statistically significant differences associated with fibrosis stage. Hierarchical clustering revealed that biopsies representative of later fibrosis stages (e.g. Batts-Ludwig stages 3-4) exhibited a distinct protein expression profile indicating an apparent down-regulation of many proteins when compared to samples from earlier fibrosis stages (e.g. Batts-Ludwig stages 0-2). Functional analysis of these signature proteins suggests that impairment of key mitochondrial processes including fatty acid oxidation and oxidative phosphorylation, and response to oxidative stress and reactive oxygen species occurs during advanced stage 3-4 fibrosis. In conclusion, the results reported here represent a significant advancement in clinical proteomics providing to our knowledge, the first demonstration of global proteomic alterations accompanying liver disease progression in patients chronically infected with HCV. Our findings contribute to a generally emerging theme associating oxidative stress and hepatic mitochondrial dysfunction with HCV pathogenesis.

  12. Paclitaxel metabolism in rat and human liver microsomes is inhibited by phenolic antioxidants.

    PubMed

    Václavíková, Radka; Horský, Stanislav; Simek, Petr; Gut, Ivan

    2003-09-01

    Paclitaxel is an important, recently introduced anti-neoplastic drug. Paclitaxel metabolites are virtually inactive in comparison with the parent drug. The study investigated whether phenolic antioxidants could inhibit metabolic inactivation sufficiently to increase paclitaxel effects. Cytochrome p450 (CYP)-catalysed metabolism of paclitaxel was investigated in rat and human liver microsomes. In rat microsomes, paclitaxel was metabolised mainly to C3'-hydroxypaclitaxel (C3'-OHP), less to C2-hydroxypaclitaxel (C2-OHP), di-hydroxypaclitaxel (di-OHP) and another monohydroxylated paclitaxel. In human liver microsomes, 6alpha-hydroxypaclitaxel (6alpha-OHP), formed by CYP2C8, was the main metabolite, while C3'-OHP, C2-OHP and another product different from di-OHP were minor metabolites, formed by CYP3A4. In individual human livers 6alpha-OHP was formed at 1.8-fold to 13-fold higher rates than C3'-OHP. Kinetic parameters (K(m) and V(max)) of production of various metabolites in rat and human liver microsomes revealed differences between species as well as human individual differences. Nine phenolic antioxidants ((+)-catechin, (-)-epicatechin, fisetin, gallic acid, morin, myricetin, naringenin, quercetin and resveratrol) were tested for inhibition of paclitaxel metabolism. In rat microsomes, resveratrol was more inhibitory than fisetin; the other phenolic antioxidants were without effect. In human microsomes, the inhibiting potency decreased in the order fisetin >quercetin >morin >resveratrol, while the other phenolic antioxidants were not inhibitory; the formation of 6alpha-OHP (CYP2C8) was generally more inhibited than that of C3'-OHP. The inhibition was mostly mixed-type. The results suggest that oral administration of some phenolic substances might increase paclitaxel blood concentrations during chemotherapy.

  13. [Effect of combined administration of Angelica polysaccharide and cytarabine on liver of human leukemia NOD/SCID mouse model].

    PubMed

    Zhu, Jia-Hong; Xu, Chun-Yan; Mu, Xin-Yi; Liu, Jun; Zhang, Meng-Si; Jia, Dao-Yong; Zhang, Yan-Yan; Huang, Guo-Ning; Wang, Ya-Ping

    2014-01-01

    Leukemia is a type of malignant tumors of hematopoietic system with the abnormal increased immature leukemia cells showing metastasis and invasion ability. Liver is one of the main targets of the leukemia cells spread to, where they may continue to proliferate and differentiate and cause liver function damage, even liver failure. Our previous studies showed that Angelica polysscharides (APS), the main effective components in Angelica sinensis of Chinese traditional medicine, was able to inhibit the proliferation and induced differentiation of the leukemia cells, however, its effect on the liver during the treatment remains elucidated. In the present study, the human leukemia NOD/SCID mouse model were established by implantation human leukemia K562 cells line, then the leukemia mouse were treated with APS, Ara-c or APS + Ara-c respectively by peritoneal injection for 14 days, to explore the effect and mechanism of the chemicals on the mouse liver. Compared to the human leukemia NOD/SCID mouse model group with the treatments of APS, Ara-c and APS + Ara-c, We found that severe liver damage and pathological changes of the liver were able to alleviate: First, the number of white blood cells in the peripheral blood was significantly lower and with less transplanted K562 leukemia cells; Second, liver function damage was alleviated as liver function tests showed that alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBiL) were significantly reduced, while the albumin (Alb) was notably increased; Third, liver antioxidant ability was improved as the activities of the antioxidant enzymes glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were significantly increased, and the contents of GSH and malonaldehyde (MDA) were decreased significantly in the liver; Fourth, the inflammation of the liver was relieved as the level of IL-1beta and IL-6, the inflammatory cytokines, were decreased significantly in the liver. Fifth, liver index

  14. Thermal neutron irradiation field design for boron neutron capture therapy of human explanted liver.

    PubMed

    Bortolussi, S; Altieri, S

    2007-12-01

    The selective uptake of boron by tumors compared to that by healthy tissue makes boron neutron capture therapy (BNCT) an extremely advantageous technique for the treatment of tumors that affect a whole vital organ. An example is represented by colon adenocarcinoma metastases invading the liver, often resulting in a fatal outcome, even if surgical resection of the primary tumor is successful. BNCT can be performed by irradiating the explanted organ in a suitable neutron field. In the thermal column of the Triga Mark II reactor at Pavia University, a facility was created for this purpose and used for the irradiation of explanted human livers. The neutron field distribution inside the organ was studied both experimentally and by means of the Monte Carlo N-particle transport code (MCNP). The liver was modeled as a spherical segment in MCNP and a hepatic-equivalent solution was used as an experimental phantom. In the as-built facility, the ratio between maximum and minimum flux values inside the phantom ((phi(max)/phi(min)) was 3.8; this value can be lowered to 2.3 by rotating the liver during the irradiation. In this study, the authors proposed a new facility configuration to achieve a uniform thermal neutron flux distribution in the liver. They showed that a phi(max)/phi(min) ratio of 1.4 could be obtained without the need for organ rotation. Flux distributions and dose volume histograms were reported for different graphite configurations. PMID:18196797

  15. Improving animal and human health through understanding liver fluke immunology.

    PubMed

    Piedrafita, D; Spithill, T W; Smith, R E; Raadsma, H W

    2010-08-01

    Sheep, goats and cattle represent the most numerous and economically important agricultural species worldwide used as sources for milk, fibre and red meat. In addition, in the developing world, these species often represent the sole asset base for small-holder livestock farmers and cattle/buffaloes often provide the majority of draught power for crop production. Production losses caused by helminth diseases of these animals are a major factor in extending the cycle of poverty in developing countries and a major food security issue for developed economies. Fasciola spp. are one of the most important zoonotic diseases with a global economic impact in livestock production systems and a poorly defined but direct effect on human health. Improvements in human and animal health will require a concerted research effort into the development of new accurate and simple diagnostic tests and increased vaccine and drug development against Fasciola infections. Here, the use of definitive natural host breeds with contrasting resistance to Fasciola infections is discussed as a resource to contrast parasite-host interactions and identify parasite immune evasion strategies. Such studies are likely to boost the discovery of new vaccine, drug and diagnostic candidates and provide the foundation for future genetic selection of resistant animals. PMID:20626812

  16. Human relevance framework for rodent liver tumors induced by the insecticide sulfoxaflor.

    PubMed

    LeBaron, Matthew J; Gollapudi, B Bhaskar; Terry, Claire; Billington, Richard; Rasoulpour, Reza J

    2014-05-01

    Sulfoxaflor, a novel active substance that targets sap-feeding insects, induced rodent hepatotoxicity when administered at high dietary doses. Specifically, hepatocellular adenomas and carcinomas increased after 18 months in male and female CD-1 mice at 750 and 1250 ppm, respectively, and hepatocellular adenomas increased after 2 years in male F344 rats at 500 ppm. Studies to determine the mode of action (MoA) for these liver tumors were performed in an integrated and prospective manner as part of the standard battery of toxicology studies such that the MoA data were available prior to, or by the time of, the completion of the carcinogenicity studies. Sulfoxaflor is not genotoxic and the MoA data support the following key events in the etiology of the rodent liver tumors: (1) CAR nuclear receptor activation and (2) hepatocellular proliferation. The MoA data were evaluated in a weight of evidence approach using the Bradford Hill criteria for causation and were found to align with dose and temporal concordance, biological plausibility, coherence, strength, consistency, and specificity for a CAR-mediated MoA while excluding other alternate MoAs. The available data include: activation of CAR, Cyp2b induction, hepatocellular hypertrophy and hyperplasia, absence of liver effects in KO mice, absence of proliferation in humanized mice, and exclusion of other possible mechanisms (e.g., genotoxicity, cytotoxicity, AhR, or PPAR activation), and indicate that the identified rodent liver tumor MoA for sulfoxaflor would not occur in humans. In this case, sulfoxaflor is considered not to be a potential human liver carcinogen. PMID:24832551

  17. Use of a three-dimensional humanized liver model for the study of viral gene vectors.

    PubMed

    Wagner, Anke; Röhrs, Viola; Materne, Eva-Maria; Hiller, Thomas; Kedzierski, Radoslaw; Fechner, Henry; Lauster, Roland; Kurreck, Jens

    2015-10-20

    Reconstituted three-dimensional (3D) liver models obtained by engrafting hepatic cells into an extracellular matrix (ECM) are valuable tools to study tissue regeneration, drug action and toxicology ex vivo. The aim of the present study was to establish a system for the functional investigation of a viral vector in a 3D liver model composed of human HepG2 cells on a rat ECM. An adeno-associated viral (AAV) vector expressing the Emerald green fluorescent protein (EmGFP) and a short hairpin RNA (shRNA) directed against human cyclophilin b (hCycB) was injected into the portal vein of 3D liver models. Application of the vector did not exert toxic effects, as shown by analysis of metabolic parameters. Six days after transduction, fluorescence microscopy analysis of EmGFP production revealed widespread distribution of the AAV vectors. After optimization of the recellularization and transduction conditions, averages of 55 and 90 internalized vector genomes per cell in two replicates of the liver model were achieved, as determined by quantitative PCR analysis. Functionality of the AAV vector was confirmed by efficient shRNA-mediated knockdown of hCycB by 70-90%. Our study provides a proof-of-concept that a recellularized biological ECM provides a valuable model to study viral vectors ex vivo. PMID:26356676

  18. Tissue inhibitor of metalloproteinase-1 and -2 RNA expression in rat and human liver fibrosis.

    PubMed Central

    Herbst, H.; Wege, T.; Milani, S.; Pellegrini, G.; Orzechowski, H. D.; Bechstein, W. O.; Neuhaus, P.; Gressner, A. M.; Schuppan, D.

    1997-01-01

    The remodeling of extracellular matrix during chronic liver disease may partially be attributed to altered activity of matrix metalloproteinases and their tissue inhibitors (TIMPs). Expression of TIMP-1 and -2 was studied by in situ hybridization combined with immunohistochemistry in rat (acute and chronic carbon tetrachloride intoxication and secondary biliary fibrosis) and human livers and on isolated rat hepatic stellate cells. TIMP-1 and -2 transcripts appeared in rat livers within 1 to 3 hours after intoxication, pointing to a role in the protection against accidental activation of matrix metalloproteinases, and were present at high levels in all fibrotic rat and human livers predominantly in stellate cells. TIMP-2 RNA distribution largely matched with previously reported patterns of matrix metalloproteinase-2 (72-kd gelatinase) expression, suggesting generation of a TIMP-2/matrix metalloproteinase-2 complex (large inhibitor of metalloproteinases). Isolated stellate cells expressed TIMP-1 and -2 RNA. Addition of transforming growth factor-beta 1 enhanced TIMP-1 and matrix metalloproteinase-2 RNA levels in vitro, whereas TIMP-2-specific signals were reduced, likely to result in a stoichiometric excess of matrix-metalloproteinase-2 over TIMP-2. In the context of previous demonstrations of transforming growth factor-beta 1 and matrix metalloproteinase-2 in vivo, these patterns suggest an intrahepatic environment permitting only limited matrix degradation, ultimately resulting in redistribution of extracellular matrix with relative accumulation of collagen type 1. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:9137090

  19. Allosteric properties of phosphate-activated glutaminase of human liver mitochondria.

    PubMed

    Snodgrass, P J; Lund, P

    1984-03-22

    The kinetics of human liver phosphate-activated glutaminase were studied in mitochondria isolated from surgical biopsies. The pH profile and activation by phosphate closely resembled rat liver glutaminase and differed clearly from human or rat kidney mitochondrial glutaminases. The activity responses to glutamine or phosphate were allosteric, showing positive cooperativity, as in the rat liver enzyme. Exogenous 1 mM NH4Cl shifted the glutamine concentration at half-maximal velocity, [Gln]0.5, to lower values without changing Vmax or sigmoidicity. Hill plots showed a parallel shift to the left with NH4Cl and the apparent number of binding sites, nH, was 2-3. 25 mM KHCO3 gave the same effects as NH4Cl on [Gln]0.5, Vmax, sigmoidicity and nH. The combination of the two activators was less than additive. Glutamate did not inhibit. We postulate that liver glutaminase is allosteric in its kinetics because it plays a key role in urea synthesis by regulating provision of glutamate for synthesis of N-acetylglutamate, the obligatory co-factor of carbamoylphosphate synthetase. PMID:6704422

  20. Long-term culture of genome-stable bipotent stem cells from adult human liver.

    PubMed

    Huch, Meritxell; Gehart, Helmuth; van Boxtel, Ruben; Hamer, Karien; Blokzijl, Francis; Verstegen, Monique M A; Ellis, Ewa; van Wenum, Martien; Fuchs, Sabine A; de Ligt, Joep; van de Wetering, Marc; Sasaki, Nobuo; Boers, Susanne J; Kemperman, Hans; de Jonge, Jeroen; Ijzermans, Jan N M; Nieuwenhuis, Edward E S; Hoekstra, Ruurdtje; Strom, Stephen; Vries, Robert R G; van der Laan, Luc J W; Cuppen, Edwin; Clevers, Hans

    2015-01-15

    Despite the enormous replication potential of the human liver, there are currently no culture systems available that sustain hepatocyte replication and/or function in vitro. We have shown previously that single mouse Lgr5+ liver stem cells can be expanded as epithelial organoids in vitro and can be differentiated into functional hepatocytes in vitro and in vivo. We now describe conditions allowing long-term expansion of adult bile duct-derived bipotent progenitor cells from human liver. The expanded cells are highly stable at the chromosome and structural level, while single base changes occur at very low rates. The cells can readily be converted into functional hepatocytes in vitro and upon transplantation in vivo. Organoids from α1-antitrypsin deficiency and Alagille syndrome patients mirror the in vivo pathology. Clonal long-term expansion of primary adult liver stem cells opens up experimental avenues for disease modeling, toxicology studies, regenerative medicine, and gene therapy. PMID:25533785

  1. Use of a three-dimensional humanized liver model for the study of viral gene vectors.

    PubMed

    Wagner, Anke; Röhrs, Viola; Materne, Eva-Maria; Hiller, Thomas; Kedzierski, Radoslaw; Fechner, Henry; Lauster, Roland; Kurreck, Jens

    2015-10-20

    Reconstituted three-dimensional (3D) liver models obtained by engrafting hepatic cells into an extracellular matrix (ECM) are valuable tools to study tissue regeneration, drug action and toxicology ex vivo. The aim of the present study was to establish a system for the functional investigation of a viral vector in a 3D liver model composed of human HepG2 cells on a rat ECM. An adeno-associated viral (AAV) vector expressing the Emerald green fluorescent protein (EmGFP) and a short hairpin RNA (shRNA) directed against human cyclophilin b (hCycB) was injected into the portal vein of 3D liver models. Application of the vector did not exert toxic effects, as shown by analysis of metabolic parameters. Six days after transduction, fluorescence microscopy analysis of EmGFP production revealed widespread distribution of the AAV vectors. After optimization of the recellularization and transduction conditions, averages of 55 and 90 internalized vector genomes per cell in two replicates of the liver model were achieved, as determined by quantitative PCR analysis. Functionality of the AAV vector was confirmed by efficient shRNA-mediated knockdown of hCycB by 70-90%. Our study provides a proof-of-concept that a recellularized biological ECM provides a valuable model to study viral vectors ex vivo.

  2. Overfeeding polyunsaturated and saturated fat causes distinct effects on liver and visceral fat accumulation in humans.

    PubMed

    Rosqvist, Fredrik; Iggman, David; Kullberg, Joel; Cedernaes, Jonathan; Johansson, Hans-Erik; Larsson, Anders; Johansson, Lars; Ahlström, Håkan; Arner, Peter; Dahlman, Ingrid; Risérus, Ulf

    2014-07-01

    Excess ectopic fat storage is linked to type 2 diabetes. The importance of dietary fat composition for ectopic fat storage in humans is unknown. We investigated liver fat accumulation and body composition during overfeeding saturated fatty acids (SFAs) or polyunsaturated fatty acids (PUFAs). LIPOGAIN was a double-blind, parallel-group, randomized trial. Thirty-nine young and normal-weight individuals were overfed muffins high in SFAs (palm oil) or n-6 PUFAs (sunflower oil) for 7 weeks. Liver fat, visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (SAT), total adipose tissue, pancreatic fat, and lean tissue were assessed by magnetic resonance imaging. Transcriptomics were performed in SAT. Both groups gained similar weight. SFAs, however, markedly increased liver fat compared with PUFAs and caused a twofold larger increase in VAT than PUFAs. Conversely, PUFAs caused a nearly threefold larger increase in lean tissue than SFAs. Increase in liver fat directly correlated with changes in plasma SFAs and inversely with PUFAs. Genes involved in regulating energy dissipation, insulin resistance, body composition, and fat-cell differentiation in SAT were differentially regulated between diets, and associated with increased PUFAs in SAT. In conclusion, overeating SFAs promotes hepatic and visceral fat storage, whereas excess energy from PUFAs may instead promote lean tissue in healthy humans.

  3. Long-Term Culture of Genome-Stable Bipotent Stem Cells from Adult Human Liver

    PubMed Central

    Huch, Meritxell; Gehart, Helmuth; van Boxtel, Ruben; Hamer, Karien; Blokzijl, Francis; Verstegen, Monique M.A.; Ellis, Ewa; van Wenum, Martien; Fuchs, Sabine A.; de Ligt, Joep; van de Wetering, Marc; Sasaki, Nobuo; Boers, Susanne J.; Kemperman, Hans; de Jonge, Jeroen; Ijzermans, Jan N.M.; Nieuwenhuis, Edward E.S.; Hoekstra, Ruurdtje; Strom, Stephen; Vries, Robert R.G.; van der Laan, Luc J.W.; Cuppen, Edwin; Clevers, Hans

    2015-01-01

    Summary Despite the enormous replication potential of the human liver, there are currently no culture systems available that sustain hepatocyte replication and/or function in vitro. We have shown previously that single mouse Lgr5+ liver stem cells can be expanded as epithelial organoids in vitro and can be differentiated into functional hepatocytes in vitro and in vivo. We now describe conditions allowing long-term expansion of adult bile duct-derived bipotent progenitor cells from human liver. The expanded cells are highly stable at the chromosome and structural level, while single base changes occur at very low rates. The cells can readily be converted into functional hepatocytes in vitro and upon transplantation in vivo. Organoids from α1-antitrypsin deficiency and Alagille syndrome patients mirror the in vivo pathology. Clonal long-term expansion of primary adult liver stem cells opens up experimental avenues for disease modeling, toxicology studies, regenerative medicine, and gene therapy. PMID:25533785

  4. Mechanism of action of novel piperazine containing a toxicant against human liver cancer cells

    PubMed Central

    Kanthimathi, MS; Haerian, Batoul Sadat

    2016-01-01

    The purpose of this study was to assess the cytotoxic potential of a novel piperazine derivative (PCC) against human liver cancer cells. SNU-475 and 423 human liver cancer cell lines were used to determine the IC50 of PCC using the standard MTT assay. PCC displayed a strong suppressive effect on liver cancer cells with an IC50 value of 6.98 ± 0.11 µM and 7.76 ± 0.45 µM against SNU-475 and SNU-423 respectively after 24 h of treatment. Significant dipping in the mitochondrial membrane potential and elevation in the released of cytochrome c from the mitochondria indicated the induction of the intrinsic apoptosis pathway by PCC. Activation of this pathway was further evidenced by significant activation of caspase 3/7 and 9. PCC was also shown to activate the extrinsic pathways of apoptosis via activation of caspase-8 which is linked to the suppression of NF-κB translocation to the nucleus. Cell cycle arrest in the G1 phase was confirmed by flow cytometry and up-regulation of glutathione reductase expression was quantified by qPCR. Results of this study suggest that PCC is a potent anti-cancer agent inducing both intrinsic and extrinsic pathways of apoptosis in liver cancer cell lines. PMID:27019772

  5. Chip-based human liver-intestine and liver-skin co-cultures--A first step toward systemic repeated dose substance testing in vitro.

    PubMed

    Maschmeyer, Ilka; Hasenberg, Tobias; Jaenicke, Annika; Lindner, Marcus; Lorenz, Alexandra Katharina; Zech, Julie; Garbe, Leif-Alexander; Sonntag, Frank; Hayden, Patrick; Ayehunie, Seyoum; Lauster, Roland; Marx, Uwe; Materne, Eva-Maria

    2015-09-01

    Systemic repeated dose safety assessment and systemic efficacy evaluation of substances are currently carried out on laboratory animals and in humans due to the lack of predictive alternatives. Relevant international regulations, such as OECD and ICH guidelines, demand long-term testing and oral, dermal, inhalation, and systemic exposure routes for such evaluations. So-called "human-on-a-chip" concepts are aiming to replace respective animals and humans in substance evaluation with miniaturized functional human organisms. The major technical hurdle toward success in this field is the life-like combination of human barrier organ models, such as intestine, lung or skin, with parenchymal organ equivalents, such as liver, at the smallest biologically acceptable scale. Here, we report on a reproducible homeostatic long-term co-culture of human liver equivalents with either a reconstructed human intestinal barrier model or a human skin biopsy applying a microphysiological system. We used a multi-organ chip (MOC) platform, which provides pulsatile fluid flow within physiological ranges at low media-to-tissue ratios. The MOC supports submerse cultivation of an intact intestinal barrier model and an air-liquid interface for the skin model during their co-culture with the liver equivalents respectively at (1)/100.000 the scale of their human counterparts in vivo. To increase the degree of organismal emulation, microfluidic channels of the liver-skin co-culture could be successfully covered with human endothelial cells, thus mimicking human vasculature, for the first time. Finally, exposure routes emulating oral and systemic administration in humans have been qualified by applying a repeated dose administration of a model substance - troglitazone - to the chip-based co-cultures.

  6. Chip-based human liver-intestine and liver-skin co-cultures--A first step toward systemic repeated dose substance testing in vitro.

    PubMed

    Maschmeyer, Ilka; Hasenberg, Tobias; Jaenicke, Annika; Lindner, Marcus; Lorenz, Alexandra Katharina; Zech, Julie; Garbe, Leif-Alexander; Sonntag, Frank; Hayden, Patrick; Ayehunie, Seyoum; Lauster, Roland; Marx, Uwe; Materne, Eva-Maria

    2015-09-01

    Systemic repeated dose safety assessment and systemic efficacy evaluation of substances are currently carried out on laboratory animals and in humans due to the lack of predictive alternatives. Relevant international regulations, such as OECD and ICH guidelines, demand long-term testing and oral, dermal, inhalation, and systemic exposure routes for such evaluations. So-called "human-on-a-chip" concepts are aiming to replace respective animals and humans in substance evaluation with miniaturized functional human organisms. The major technical hurdle toward success in this field is the life-like combination of human barrier organ models, such as intestine, lung or skin, with parenchymal organ equivalents, such as liver, at the smallest biologically acceptable scale. Here, we report on a reproducible homeostatic long-term co-culture of human liver equivalents with either a reconstructed human intestinal barrier model or a human skin biopsy applying a microphysiological system. We used a multi-organ chip (MOC) platform, which provides pulsatile fluid flow within physiological ranges at low media-to-tissue ratios. The MOC supports submerse cultivation of an intact intestinal barrier model and an air-liquid interface for the skin model during their co-culture with the liver equivalents respectively at (1)/100.000 the scale of their human counterparts in vivo. To increase the degree of organismal emulation, microfluidic channels of the liver-skin co-culture could be successfully covered with human endothelial cells, thus mimicking human vasculature, for the first time. Finally, exposure routes emulating oral and systemic administration in humans have been qualified by applying a repeated dose administration of a model substance - troglitazone - to the chip-based co-cultures. PMID:25857839

  7. Novel piperazine core compound induces death in human liver cancer cells: possible pharmacological properties

    PubMed Central

    Samie, Nima; Muniandy, Sekaran; Kanthimathi, M. S.; Haerian, Batoul Sadat; Raja Azudin, Raja Elina

    2016-01-01

    The current study evaluates the cytotoxic mechanism of a novel piperazine derivate designated as PCC against human liver cancer cells. In this context, human liver cancer cell lines, SNU-475 and 243, human monocyte/macrophage cell line, CRL-9855, and human B lymphocyte cell line, CCL-156, were used to determine the IC50 of PCC using the standard MTT assay. PCC displayed a strong suppressive effect on SNU-475 and SNU-423 cells with an IC50 value of 6.98 ± 0.11 μg/ml and 7.76 ± 0.45 μg/ml respectively, after 24 h of treatment. Significant dipping in the mitochondrial membrane potential and elevation in the released of cytochrome c from the mitochondria indicated the induction of the intrinsic apoptosis pathway by PCC. Activation of this pathway was further evidenced by significant activation of caspase 3/7 and 9. PCC was also shown to activate the extrinsic pathways of apoptosis via activation of caspase-8 which is linked to the suppression of NF-ƙB translocation to the nucleus. Cell cycle arrest in the G1 phase was confirmed by flow cytometry and up-regulation of glutathione reductase expression was quantified by qPCR. This study suggests that PCC is a simultaneous inducer of intrinsic and extrinsic pathways of apoptosis in liver cancer cell lines. PMID:27072064

  8. Toxicogenomics-based prediction of acetaminophen-induced liver injury using human hepatic cell systems.

    PubMed

    Rodrigues, Robim M; Heymans, Anja; De Boe, Veerle; Sachinidis, Agapios; Chaudhari, Umesh; Govaere, Olivier; Roskams, Tania; Vanhaecke, Tamara; Rogiers, Vera; De Kock, Joery

    2016-01-01

    Primary human hepatocytes (hHEP), human HepaRG and HepG2 cell lines are the most used human liver-based in vitro models for hepatotoxicity testing, including screening of drug-induced liver injury (DILI)-inducing compounds. hHEP are the reference hepatic in vitro system, but their availability is limited and the cells available for toxicology studies are often of poor quality. Hepatic cell lines on the other hand are highly proliferative and represent an inexhaustible hepatic cell source. However, these hepatoma-derived cells do not represent the population diversity and display reduced hepatic metabolism. Alternatively, stem cell-derived hepatic cells, which can be produced in high numbers and can differentiate into multiple cell lineages, are also being evaluated as a cell source for in vitro hepatotoxicity studies. Human skin-derived precursors (hSKP) are post-natal stem cells that, after conversion towards hepatic cells (hSKP-HPC), respond to hepatotoxic compounds in a comparable way as hHEP. In the current study, four different human hepatic cell systems (hSKP-HPC, hHEP, HepaRG and HepG2) are evaluated for their capacity to predict hepatic toxicity. Their hepatotoxic response to acetaminophen (APAP) exposure is compared to data obtained from patients suffering from APAP-induced acute liver failure (ALF). The results indicate that hHEP, HepaRG and hSKP-HPC identify comparable APAP-induced hepatotoxic functions and that HepG2 cells show the slightest hepatotoxic response. Pathway analyses further points out that HepaRG cells show the highest predicted activation of the functional genes related to 'damage of liver', followed by hSKP-HPC and hHEP cells that generated similar results. HepG2 did not show any activation of this function. PMID:26497421

  9. Putative prethymic T cell precursors within the early human embryonic liver: a molecular and functional analysis

    PubMed Central

    1993-01-01

    Hematopoietic cells present in the liver in early human fetal life were characterized by phenotypic analysis using a broad panel of monoclonal antibodies. Expression of very late antigen 4 and leukocyte function- associated antigen 3 cell adhesion receptors and 4F2 cell activation molecules was found in all fetal liver hematopoietic cells before acquisition of T cell-, B cell-, or myeloid-specific surface markers, and before the time of intrathymic colonization. Molecular studies showed that expression of the interleukin 2 receptor beta (IL-2R beta) also occurred in the embryonic liver at this early ontogenic stage. In contrast, no expression of IL-2R alpha or IL-2 transcripts was found in fetal liver cells, whereas transcription of the IL-4 gene was detected in a small fetal liver cell subset. Putative T cell precursors were identified among the hematopoietic fetal liver cells by the expression of genes encoding the gamma, delta, epsilon, and zeta invariant chains of the CD3-T cell receptor (TCR) complex. However, no transcription of the polymorphic alpha and beta TCR genes was detected. Functional in vitro assays further demonstrated that fetal liver hematopoietic cells from those early embryos were capable of proliferating in response to T cell growth factors, including IL-4 and IL-2. However, whereas IL-4- induced proliferation paralleled the appearance in vitro of CD45+CD7- CD4dull cells expressing the CD14 myeloid antigen, as well as of CD34+ primitive hematopoietic progenitors, differentiation into CD45+CD7+CD8+CD3- immature T cells was observed when using IL-2. Moreover, coculture with thymic epithelial cell monolayers provided additional evidence that early fetal liver hematopoietic cells may include very primitive T cell precursors, which were able to differentiate in vitro into TCR alpha/beta+ mature T cells. Therefore, our results indicate that, after triggering of the T cell-specific maturation program in primitive fetal liver hematopoietic progenitors

  10. In vitro biotransformation of tris(2-butoxyethyl) phosphate (TBOEP) in human liver and serum

    SciTech Connect

    Van den Eede, Nele; Erratico, Claudio; Exarchou, Vassiliki; Maho, Walid; Neels, Hugo; Covaci, Adrian

    2015-04-15

    Tris(2-butoxyethyl) phosphate (TBOEP) is a plasticizer present in indoor dust, reaching levels of several micrograms per gram. Such levels could lead to significant daily exposure of adults and children. Currently, no toxicokinetic data are available to estimate TBOEP clearance in humans after uptake and therefore, one objective of this study was to investigate intrinsic clearance of TBOEP by human liver microsome (HLM) and serum enzymes. Another objective was to generate information to identify and prioritize several metabolites of TBOEP for investigation of human exposure by biomonitoring. 1D and 2D-NMR methodologies were successfully applied on a mixture of the metabolites to confirm the structure of 3-HO-TBOEP (bis(2-butoxyethyl) 3-hydroxyl-2-butoxyethyl phosphate) and to tentatively assign structures to 1-HO-TBOEP and 2-HO-TBOEP. HO-TBOEP isomers and bis(2-butoxyethyl) phosphate (BBOEP), bis(2-butoxyethyl) hydroxyethyl phosphate (BBOEHEP) were further monitored by liquid chromatography–tandem mass spectrometry. Rates of formation of BBOEHEP and HO-TBOEP metabolites by liver enzymes were best described by the Michaelis–Menten model. Apparent K{sub m} values for BBOEHEP, 3-HO-TBOEP, and sum of 1- and 2-HO-TBOEP isomer formation were 152, 197 and 148 μM, respectively. Apparent V{sub max} values for the formation of BBOEHEP, 3-HO-TBOEP, and the sum of 1- and 2-HO-TBOEP isomers were 2560, 643, and 254 pmol/min/mg protein, respectively. No detectable formation of BBOEP occurred with liver or serum enzymes. Our findings indicate that intrinsic clearance of TBOEP is mainly catalyzed by oxidative enzymes in the liver and that its major in vitro metabolite is BBOEHEP. These findings can be applied in human biomonitoring studies and risk assessment. - Highlights: • First steps in the elucidation of TBOEP toxicokinetics • Quantification of TBOEP metabolites in human serum and liver microsomes • No detectable formation of BBOEP occurred with liver or serum

  11. Definition of the transcription initiation site of human plasminogen gene in liver and non hepatic cell lines.

    PubMed

    Malgaretti, N; Bruno, L; Pontoglio, M; Candiani, G; Meroni, G; Ottolenghi, S; Taramelli, R

    1990-12-31

    We have mapped the cap site of the human plasminogen mRNA by primer extension and PCR techniques and found that it is located at position -161 relative to the first ATG, 97 bases upstream to the 5' end of the previously isolated cDNA clone. Seven human hepatic and non hepatic cell lines and fresh liver cells were tested for human plasminogen mRNA expression: the liver and the liver derived HepG2 cell line represent the major site of plasminogen RNA synthesis while the other cell lines (Hep3B, HeLa, IMR, 293 CaCo and SW626) show much lower levels.

  12. Dissociation and rate constants of some human liver alcohol dehydrogenase isoenzymes.

    PubMed

    Pietruszko, R; de Zalenski, C; Theorell, H

    1976-01-01

    ADH from human liver forms binary complexes with NADH, associated with a blue shift of the peak of the fluorescence emission of NADH. The wavelength shift is the same for all isoenzymes but the accompanying intensification of the fluorescence is different. The fluorescence is further increased by the formation of the very tight ternary enzyme-NADH-isobutyramide complexes. These properties are similar to those for the horse liver ADH, as well as the molecular weight of E=40 000 per active site of the dimer molecule (EE). "Stopped-flow" determined velocity constants (ER in equilibrium E+R) were found to be in good agreement with ethanol activity constants previously determined by activity measurement, confirming the validity of the ordered ternary complex mechanism also for the human ADH. No single isoenzyme activity as high as that reported by Mourad and Woronick or Drum has been found. PMID:184631

  13. Liver regeneration.

    PubMed

    Mao, Shennen A; Glorioso, Jaime M; Nyberg, Scott L

    2014-04-01

    The liver is unique in its ability to regenerate in response to injury. A number of evolutionary safeguards have allowed the liver to continue to perform its complex functions despite significant injury. Increased understanding of the regenerative process has significant benefit in the treatment of liver failure. Furthermore, understanding of liver regeneration may shed light on the development of cancer within the cirrhotic liver. This review provides an overview of the models of study currently used in liver regeneration, the molecular basis of liver regeneration, and the role of liver progenitor cells in regeneration of the liver. Specific focus is placed on clinical applications of current knowledge in liver regeneration, including small-for-size liver transplant. Furthermore, cutting-edge topics in liver regeneration, including in vivo animal models for xenogeneic human hepatocyte expansion and the use of decellularized liver matrices as a 3-dimensional scaffold for liver repopulation, are proposed. Unfortunately, despite 50 years of intense study, many gaps remain in the scientific understanding of liver regeneration.

  14. Liver Regeneration

    PubMed Central

    Mao, Shennen A; Glorioso, Jaime M; Nyberg, Scott L

    2014-01-01

    The liver is unique in its ability to regenerate in response to injury. A number of evolutionary safeguards have allowed the liver to continue to perform its complex functions despite significant injury. Increased understanding of the regenerative process has significant benefit in the treatment of liver failure. Furthermore, understanding of liver regeneration may shed light on the development of cancer within the cirrhotic liver. This review will provide an overview of the models of study currently utilized in liver regeneration, the molecular basis of liver regeneration, and the role of liver progenitor cells in regeneration of the liver. Specific focus will be placed on clinical applications of current knowledge in liver regeneration including small for size liver transplant. Furthermore, cutting edge topics in liver regeneration including in vivo animal models for xenogeneic human hepatocyte expansion and the use of decellularized liver matrices as a three dimensional scaffold for liver repopulation will be proposed. Unfortunately, despite 50 years of intense study, many gaps remain in the scientific understanding of liver regeneration. PMID:24495569

  15. In vitro biotransformation of tris(2-butoxyethyl) phosphate (TBOEP) in human liver and serum.

    PubMed

    Van den Eede, Nele; Erratico, Claudio; Exarchou, Vassiliki; Maho, Walid; Neels, Hugo; Covaci, Adrian

    2015-04-15

    Tris(2-butoxyethyl) phosphate (TBOEP) is a plasticizer present in indoor dust, reaching levels of several micrograms per gram. Such levels could lead to significant daily exposure of adults and children. Currently, no toxicokinetic data are available to estimate TBOEP clearance in humans after uptake and therefore, one objective of this study was to investigate intrinsic clearance of TBOEP by human liver microsome (HLM) and serum enzymes. Another objective was to generate information to identify and prioritize several metabolites of TBOEP for investigation of human exposure by biomonitoring. 1D and 2D-NMR methodologies were successfully applied on a mixture of the metabolites to confirm the structure of 3-HO-TBOEP (bis(2-butoxyethyl) 3-hydroxyl-2-butoxyethyl phosphate) and to tentatively assign structures to 1-HO-TBOEP and 2-HO-TBOEP. HO-TBOEP isomers and bis(2-butoxyethyl) phosphate (BBOEP), bis(2-butoxyethyl) hydroxyethyl phosphate (BBOEHEP) were further monitored by liquid chromatography-tandem mass spectrometry. Rates of formation of BBOEHEP and HO-TBOEP metabolites by liver enzymes were best described by the Michaelis-Menten model. Apparent Km values for BBOEHEP, 3-HO-TBOEP, and sum of 1- and 2-HO-TBOEP isomer formation were 152, 197 and 148μM, respectively. Apparent Vmax values for the formation of BBOEHEP, 3-HO-TBOEP, and the sum of 1- and 2-HO-TBOEP isomers were 2560, 643, and 254pmol/min/mg protein, respectively. No detectable formation of BBOEP occurred with liver or serum enzymes. Our findings indicate that intrinsic clearance of TBOEP is mainly catalyzed by oxidative enzymes in the liver and that its major in vitro metabolite is BBOEHEP. These findings can be applied in human biomonitoring studies and risk assessment. PMID:25681655

  16. Nuclear microscopy of single whole cultured cells: Preparation and analysis of human Chang liver cells

    NASA Astrophysics Data System (ADS)

    Thong, P. S. P.; Watt, F.; Paramanantham, R.; Bay, B. H.; Sit, K. H.

    1997-07-01

    Nuclear microscopy is a powerful tool for the measurement of elemental concentrations in single cells. Six methods involving the use of various fixing agents, rinsing agents and drying methods were tried in the preparation of cultured human Chang liver cells for nuclear microscopy and the suitability of each method was evaluated by monitoring the {K}/{Na} ratios and shapes of individual cells. The {K}/{Na} ratio is a commonly used criteria for the ionic integrity of cells; {K}/{Na} ratios well above 1 indicates minimal perturbation of the intracellular ionic composition. Non-stimulated human Chang liver cells in a resting state are usually polygonal in shape and flattened in firm anchorage to the substrate, while dividing or stimulated cells appear rounded. Therefore the shapes of the cells can be used as an indicator of whether the cells are in a resting or stimulated state. It is not desirable for cells to be in a stimulated state since then the effects of other external stimuli cannot be observed independently. Of the six methods tested, chemical fixation, as expected, was considered non-ideal for the preparation of human cultured Chang liver cells. Ice-cold 150 mM sucrose was found to be the most suitable rinsing solution for the preparation of cultured human Chang liver cells. Both freeze-drying and air-drying were used as drying methods and cells processed by either method were found to have {K}/{Na} ratios well above 1. Hence both drying methods were found to be suitable although membrane blotting followed by air-drying was preferred as excess rinsing solution can be very quickly removed during the blotting process. The {K}/{Na} ratios of cells on the same target holder but from different regions were found to be dependent on the local cell density. Cells which are locally dense-packed were found to have a much higher {K}/{Na} ratio than cells in a less dense region.

  17. In vitro metabolism of a new cardioprotective agent, KR-32570, in human liver microsomes.

    PubMed

    Kim, Hyojin; Kang, Suil; Kim, Hyunmi; Yoon, Yune-Jung; Cha, Eun-Young; Lee, Hye Suk; Kim, Jeong-Han; Yea, Sung Su; Lee, Sang-Seop; Shin, Jae-Gook; Liu, Kwang-Hyeon

    2006-01-01

    KR-32570 (5-(2-methoxy-5-chlorophenyl)furan-2-ylcarbonyl)guanidine) is a new reversible Na+/H+ exchanger inhibitor for preventing ischemia-reperfusion injury. This study was performed to identify the metabolic pathway of KR-32570 in human liver microsomes. Human liver microsomal incubation of KR-32570 in the presence of NADPH and UDPGA resulted in the formation of six metabolites, M1-M6. M1 was identified as O-desmethyl-KR-32570, on the basis of liquid chromatography/tandem mass spectrometric (LC/MS/MS) analysis with the synthesized authentic standard. M2 and M3 were suggested to be hydroxy-KR-32570 and hydroxy-O-desmethyl-KR-32570, respectively. M1, M2, and M3 were further metabolized to their glucuronide conjugates, M4, M5, and M6, respectively. In addition, the specific P450 isoforms responsible for KR-32570 oxidation to two major metabolites, O-desmethyl-KR-32570 and hydroxy-KR-32570, were identified using a combination of correlation analysis, chemical inhibition in human liver microsomes and metabolism by expressed recombinant P450 isoforms. The inhibitory potency of KR-32570 on clinically major P450s was investigated in human liver microsomes. The results show that CYP3A4 contributes to the oxidation of KR-32570 to hydroxy-KR-32570, and CYP1A2 play the predominant role in O-demethylation of KR-32570. KR-32570 was found to inhibit moderately the metabolism of CYP2C8 substrates.

  18. The significance of the nuclear and cytoplasmic localization of metallothionein in human liver and tumor cells.

    PubMed

    Cherian, M G

    1994-09-01

    Metallothioneins are a group of low-molecular-weight intracellular proteins present in high levels in fetal mammalian livers, bound to zinc and copper. They are also present in two major isoforms in low basal levels in various organs of adults in several species. Although a number of functions have been proposed for metallothioneins, their major biological roles may be in the storage of zinc and copper during rapid growth and development, and also in the detoxification of certain toxic metals. In adult liver, metallothionein is mainly localized in the cytoplasm, it is localized also in the hepatocyte nuclei in human fetal liver and fetal and neonatal rat liver, as determined by immunohistochemical staining with a specific metallothionein antibody. Because of its high expression in fetal development, the potential role of metallothioneins in human tumors was investigated. The cellular localization of metallothionein was demonstrated in various human tumors such as thyroid tumors, testicular germ cell carcinoma, bladder transitional cell carcinomas, and salivary gland tumors. In most of these tumor tissues, metallothioneins were found in high levels in nucleus and cytoplasm in both benign and malignant tumors, although the proliferating edge of the malignant tumors showed most intense metallothionein staining. The expression of metallothionein is not universal to all tumor growth; its presence may depend on various factors, such as the type of tumor, cellular origin, morphological heterogeneity, or stage of growth. Human testicular seminomas, which are well differentiated, showed little expression of metallothionein irrespective of the staging, as compared to less well-differentiated embryonal carcinomas.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Soil and river contamination patterns of chlordecone in a tropical volcanic catchment in the French West Indies (Guadeloupe).

    PubMed

    Crabit, A; Cattan, P; Colin, F; Voltz, M

    2016-05-01

    The aim of this study was to identify primary flow paths involved in the chlordecone (CLD) river contamination and quantify the CLD fluxes to assess CLD pollution levels and duration according to a typical catchment of the banana cropping area in the French Indies (Guadeloupe): the Pérou Catchment (12 km(2)) characterized by heavy rainfall (5686 mm year(-1)). Three sub-catchments (SC1, SC2 and SC3) were studied during the hydrological year 2009-2010: a pedological survey combined with a spatialized hydrochemical approach was conducted. The average soil concentration is higher in the Pérou Catchment (3400 μg kg(-1)) than in the entire banana cropping area in Guadeloupe (2100 μg kg(-1)). The results showed that CLD stocks in soils vary largely among soil types and farming systems: the weakest stocks are located upstream in SC1 (5 kg ha(-1)), where a majority of the area is non-cultivated; medium stocks are located in Nitisols downstream in SC3 (9 kg ha(-1)); and the greatest stocks are observed in SC2 on Andosols (12 kg ha(-1)) characterized by large farms. The annual water balance and the hydro-chemical analysis revealed that the three sub-catchments exhibited different behaviors. Pérou River contamination was high during low flows, which highlighted that contamination primarily originated from groundwater contributions. The results showed that only a small part of the catchment (SC2), contributing little to the water flow, comprises a major CLD contribution, which is in agreement with the highly contaminated andosol soils observed there. Another significant result considers that at least 50 years would be required to export the totality of the actual CLD soil stocks retained in the topsoil layer. The actual time for soil remediation will however be much longer considering (i) the necessary time for the chlordecone to percolate and be stored in the shallow aquifers and (ii) its travel time to reach the river. PMID:27039897

  20. Soil and river contamination patterns of chlordecone in a tropical volcanic catchment in the French West Indies (Guadeloupe).

    PubMed

    Crabit, A; Cattan, P; Colin, F; Voltz, M

    2016-05-01

    The aim of this study was to identify primary flow paths involved in the chlordecone (CLD) river contamination and quantify the CLD fluxes to assess CLD pollution levels and duration according to a typical catchment of the banana cropping area in the French Indies (Guadeloupe): the Pérou Catchment (12 km(2)) characterized by heavy rainfall (5686 mm year(-1)). Three sub-catchments (SC1, SC2 and SC3) were studied during the hydrological year 2009-2010: a pedological survey combined with a spatialized hydrochemical approach was conducted. The average soil concentration is higher in the Pérou Catchment (3400 μg kg(-1)) than in the entire banana cropping area in Guadeloupe (2100 μg kg(-1)). The results showed that CLD stocks in soils vary largely among soil types and farming systems: the weakest stocks are located upstream in SC1 (5 kg ha(-1)), where a majority of the area is non-cultivated; medium stocks are located in Nitisols downstream in SC3 (9 kg ha(-1)); and the greatest stocks are observed in SC2 on Andosols (12 kg ha(-1)) characterized by large farms. The annual water balance and the hydro-chemical analysis revealed that the three sub-catchments exhibited different behaviors. Pérou River contamination was high during low flows, which highlighted that contamination primarily originated from groundwater contributions. The results showed that only a small part of the catchment (SC2), contributing little to the water flow, comprises a major CLD contribution, which is in agreement with the highly contaminated andosol soils observed there. Another significant result considers that at least 50 years would be required to export the totality of the actual CLD soil stocks retained in the topsoil layer. The actual time for soil remediation will however be much longer considering (i) the necessary time for the chlordecone to percolate and be stored in the shallow aquifers and (ii) its travel time to reach the river.

  1. Transient Expression of Transgenic IL-12 in Mouse Liver Triggers Unremitting Inflammation Mimicking Human Autoimmune Hepatitis.

    PubMed

    Gil-Farina, Irene; Di Scala, Marianna; Salido, Eduardo; López-Franco, Esperanza; Rodríguez-García, Estefania; Blasi, Mercedes; Merino, Juana; Aldabe, Rafael; Prieto, Jesús; Gonzalez-Aseguinolaza, Gloria

    2016-09-15

    The etiopathogenesis of autoimmune hepatitis (AIH) remains poorly understood. In this study, we sought to develop an animal model of human AIH to gain insight into the immunological mechanisms driving this condition. C57BL/6 mice were i.v. injected with adeno-associated viral vectors encoding murine IL-12 or luciferase under the control of a liver-specific promoter. Organ histology, response to immunosuppressive therapy, and biochemical and immunological parameters, including Ag-specific humoral and cellular response, were analyzed. Mechanistic studies were carried out using genetically modified mice and depletion of lymphocyte subpopulations. Adeno-associated virus IL-12-treated mice developed histological, biochemical, and immunological changes resembling type 1 AIH, including marked and persistent liver mononuclear cell infiltration, hepatic fibrosis, hypergammaglobulinemia, anti-nuclear and anti-smooth muscle actin Abs, and disease remission with immunosuppressive drugs. Interestingly, transgenic IL-12 was short-lived, but endogenous IL-12 expression was induced, and both IL-12 and IFN-γ remained elevated during the entire study period. IFN-γ was identified as an essential mediator of liver damage, and CD4 and CD8 T cells but not NK, NKT, or B cells were essential executors of hepatic injury. Furthermore, both MHC class I and MHC class II expression was upregulated at the hepatocellular membrane, and induction of autoreactive liver-specific T cells was detected. Remarkably, although immunoregulatory mechanisms were activated, they only partially mitigated liver damage. Thus, low and transient expression of transgenic IL-12 in hepatocytes causes loss of tolerance to hepatocellular Ags, leading to chronic hepatitis resembling human AIH type 1. This model provides a practical tool to explore AIH pathogenesis and novel therapies. PMID:27511737

  2. Role of inflammation and infection in the pathogenesis of human acute liver failure: Clinical implications for monitoring and therapy

    PubMed Central

    Donnelly, Mhairi C; Hayes, Peter C; Simpson, Kenneth J

    2016-01-01

    Acute liver failure is a rare and devastating clinical condition. At present, emergency liver transplantation is the only life-saving therapy in advanced cases, yet the feasibility of transplantation is affected by the presence of systemic inflammation, infection and resultant multi-organ failure. The importance of immune dysregulation and acquisition of infection in the pathogenesis of acute liver failure and its associated complications is now recognised. In this review we discuss current thinking regarding the role of infection and inflammation in the pathogenesis of and outcome in human acute liver failure, the implications for the management of such patients and suggest directions for future research. PMID:27468190

  3. In vitro metabolism of 2-ethylhexyldiphenyl phosphate (EHDPHP) by human liver microsomes.

    PubMed

    Ballesteros-Gómez, Ana; Erratico, Claudio A; Eede, Nele Van den; Ionas, Alin C; Leonards, Pim E G; Covaci, Adrian

    2015-01-01

    2-ethylhexyl diphenyl phosphate (EHDPHP) is used as flame retardant and plasticizer additive in a variety of consumer products. Since EHDPHP is toxic to aquatic organisms and has been detected in environmental samples, concerns about human exposure and toxicity are emerging. With the aim of identifying human-specific metabolites, the biotransformation of EHDPHP was investigated using human liver microsomes. Using an in silico program (Meteor) for the prediction of metabolites, untargeted screening tools (agilent Mass Hunter) and a suitable analysis platform based on ultra-high performance liquid chromatography (UPLC) and quadrupole time-of-flight high resolution mass spectrometer (QTOF-MS), for the first time a wide variety of phases-I and II metabolites of EHDPHP were identified. Mono- and di-hydroxylated metabolites, keto metabolites, mixed keto and hydroxylated metabolites and diphenyl phosphate were the major phase-I metabolites of EHDPHP. Glucuronidated metabolites of phase-I metabolites of EHDPHP were also formed by human liver microsomes. Using these results, we propose a general metabolism pathway for EHDPHP in humans and a number of candidate biomarkers for assessing the human exposure to this ubiquitous phosphate flame retardant and plasticizer in future biomonitoring studies. Furthermore, we provide a template analytical approach based on the combination of untargeted and targeted screening and UPLC-QTOF-MS analysis suitable for use in future metabolism studies. PMID:25448284

  4. Molecular cloning, chromosomal localization, and functional characterization of a human liver Na+/bile acid cotransporter.

    PubMed Central

    Hagenbuch, B; Meier, P J

    1994-01-01

    We have used a cDNA probe from a cloned rat liver Na+/taurocholate cotransporting polypeptide (Ntcp) to screen a human liver cDNA library. A 1,599-bp cDNA clone that encodes a human Na+/taurocholate cotransporting polypeptide (NTCP) was isolated. The human NTCP consists of 349 amino acids (calculated molecular mass of 38 kD) and exhibits 77% amino acid homology with the rat Ntcp. In vitro translation experiments indicate that the protein is glycosylated and has a molecular weight similar to the rat Ntcp. Injection of in vitro transcribed cRNA into Xenopus laevis oocytes resulted in the expression of Na(+)-dependent taurocholate uptake. Saturation kinetics indicated that the human NTCP has a higher affinity for taurocholate (apparent Km = 6 microM) than the previously cloned rat protein (apparent Km = 25 microM). NTCP-mediated taurocholate uptake into oocytes was inhibited by all major bile acid derivatives (100 microM), bumetanide (500 microM), and bromosulphophthalein (100 microM). Southern blot analysis of genomic DNA from a panel of human/hamster somatic cell hybrids mapped the human NTCP gene to chromosome 14. PMID:8132774

  5. Plasmodium falciparum full life cycle and Plasmodium ovale liver stages in humanized mice

    PubMed Central

    Soulard, Valérie; Bosson-Vanga, Henriette; Lorthiois, Audrey; Roucher, Clémentine; Franetich, Jean- François; Zanghi, Gigliola; Bordessoulles, Mallaury; Tefit, Maurel; Thellier, Marc; Morosan, Serban; Le Naour, Gilles; Capron, Frédérique; Suemizu, Hiroshi; Snounou, Georges; Moreno-Sabater, Alicia; Mazier, Dominique

    2015-01-01

    Experimental studies of Plasmodium parasites that infect humans are restricted by their host specificity. Humanized mice offer a means to overcome this and further provide the opportunity to observe the parasites in vivo. Here we improve on previous protocols to achieve efficient double engraftment of TK-NOG mice by human primary hepatocytes and red blood cells. Thus, we obtain the complete hepatic development of P. falciparum, the transition to the erythrocytic stages, their subsequent multiplication, and the appearance of mature gametocytes over an extended period of observation. Furthermore, using sporozoites derived from two P. ovale-infected patients, we show that human hepatocytes engrafted in TK-NOG mice sustain maturation of the liver stages, and the presence of late-developing schizonts indicate the eventual activation of quiescent parasites. Thus, TK-NOG mice are highly suited for in vivo observations on the Plasmodium species of humans. PMID:26205537

  6. Molecular cloning of the flavin-containing monooxygenase (form II) cDNA from adult human liver.

    PubMed Central

    Lomri, N; Gu, Q; Cashman, J R

    1992-01-01

    Complementary DNA (cDNA) clones encoding the adult human liver flavin-containing monooxygenase (FMO; dimethylaniline N-oxidase, EC 1.14.13.8) were isolated from lambda gt10 and lambda gt11 libraries. The cDNA libraries were screened with three synthetic 36-mer oligonucleotide probes derived from the nucleic acid sequence of the pig liver FMO cDNA. The deduced amino acid sequence for the adult human liver FMO was quite distinct from the pig liver FMO, and adult human liver FMO was designated form II (HLFMO II). The full-length cDNA sequence of HLFMO II [2119 base pairs (bp)] had an open reading frame of 1599 nucleotides, which encoded a 533-amino acid protein of Mr 59,179, a 5'-noncoding region of 136 nucleotides and a 3'-noncoding region of 369 nucleotides excluding the poly(A) tail. The deduced amino acid sequence of HLFMO II had 80% similarity with the rabbit liver FMO II but only a 52%, 55%, and 53% amino acid similarity with the rabbit liver (form I), the pig liver (form I), and fetal human liver (form I) FMOs, respectively. RNA analysis of adult human liver RNA showed that there was one HLFMO II mRNA species. Analysis of genomic DNA indicated that HLFMO II was the product of a single gene. These results indicated that the deduced amino acid sequence for HLFMO II contained highly conserved residues and suggested that FMO enzymes were closely related and, undoubtedly, derived from the same ancestral gene. Images PMID:1542660

  7. Selective Protection of Human Liver Tissue in TNF-Targeting of Cancers of the Liver by Transient Depletion of Adenosine Triphosphate

    PubMed Central

    Weiland, Timo; Klein, Kathrin; Zimmermann, Martina; Speicher, Tobias; Venturelli, Sascha; Berger, Alexander; Bantel, Heike; Königsrainer, Alfred; Schenk, Martin; Weiss, Thomas S.; Wendel, Albrecht; Schwab, Matthias; Bitzer, Michael; Lauer, Ulrich M.

    2012-01-01

    Background Tumor necrosis factor alpha (TNF) is able to kill cancer cells via receptor-mediated cell death requiring adenosine triphosphate (ATP). Clinical usage of TNF so far is largely limited by its profound hepatotoxicity. Recently, it was found in the murine system that specific protection of hepatocytes against TNF's detrimental effects can be achieved by fructose-mediated ATP depletion therein. Before employing this quite attractive selection principle in a first clinical trial, we here comprehensively investigated the interdependence between ATP depletion and TNF hepatotoxicity in both in vitro and ex vivo experiments based on usage of primary patient tissue materials. Methods Primary human hepatocytes, and both non-tumorous and tumorous patient-derived primary liver tissue slices were used to elucidate fructose-induced ATP depletion and TNF-induced cytotoxicity. Results PHH as well as tissue slices prepared from non-malignant human liver specimen undergoing a fructose-mediated ATP depletion were both demonstrated to be protected against TNF-induced cell death. In contrast, due to tumor-specific overexpression of hexokinase II, which imposes a profound bypass on hepatocytic-specific fructose catabolism, this was not the case for human tumorous liver tissues. Conclusion Normal human liver tissues can be protected transiently against TNF-induced cell death by systemic pretreatment with fructose used in non-toxic/physiologic concentrations. Selective TNF-targeting of primary and secondary tumors of the liver by transient and specific depletion of hepatocytic ATP opens up a new clinical avenue for the TNF-based treatment of liver cancers. PMID:23272249

  8. Induction of Three-Dimensional Growth of Human Liver Cells in Simulated Microgravity

    NASA Technical Reports Server (NTRS)

    Pellis, Neal R.; Khaoustov, V. I.; Yoffe, B.; Murry, D. J.; Soriano, H. E.; Risin, D.; Dawson, David L. (Technical Monitor)

    1999-01-01

    We previously reported that a NASA-developed bioreactor that simulates microgravity environment and creates the unique environment of low shear force and high-mass transfer is conducive for maintaining long term 3-D cell cultures of functional hepatocytes (60 days). However, significant further expansion of liver mass, or the remodeling of liver in vitro was jeopardized by the appearance of apoptotic zones in the center of large cell aggregates. To optimize oxygenation and nutritional uptake within growing cellular aggregates we cultured primary human liver cells (HLC) in a bioreactor in the presence or absence of microcarriers and biodegradable scaffolds. Also, to promote angiogenesis, HLC were cultured with or without microvascular endothelial cells. HLC were harvested from human livers by collagenase perfusion. While microcarriers did not affect cell growth, HLC cultured with biodegradable scaffolds made from polyglycolic acid (PGA) formed aggregates up to 3 cm in length. Culturing cells with PGA scaffolds increased the efficiency of cell self-assembly and the formation of larger cell aggregates. Based on histological evaluation it appears that the degree of apoptotic cells was diminished as compared to cultures without scaffolds. Histology of HLC with PGA-scaffolds revealed cell distribution between the fibers of the scaffolds, and cell-cell and cell-fiber interactions. Analyses of HLC spheroids revealed tissue-like structures comprised of hepatocytes, biliary epithelial cells and/or progenitor liver cells that were arranged as bile duct-like structures along nascent vascular sprouts. Electron microscopy revealed groups of cohesive hepatocytes and bile canaliculi with multiple microvilli and tight cellular junctions. Hepatocytes were further organized into tight clusters surrounded by complex stromal structures and reticulin fibers. Also, we observed higher levels of albumin mRNA expression when hepatocytes were co-cultured with endothelial cells. To evaluate

  9. 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

  10. 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

  11. Molecular Recognition of Human Liver Cancer Cells Using DNA Aptamers Generated via Cell-SELEX

    PubMed Central

    Zhang, Liqin; Delgado, Stefanie; Champanhac, Carole; Cansiz, Sena; Wu, Cuichen; Shan, Hong; Tan, Weihong

    2015-01-01

    Most clinical cases of liver cancer cannot be diagnosed until they have evolved to an advanced stage, thus resulting in high mortality. It is well recognized that the implementation of early detection methods and the development of targeted therapies for liver cancer are essential to reducing the high mortality rates associated with this disease. To achieve these goals, molecular probes capable of recognizing liver cancer cell-specific targets are needed. Here we describe a panel of aptamers able to distinguish hepatocarcinoma from normal liver cells. The aptamers, which were selected by cell-based SELEX (Systematic Evolution of Ligands by Exponential Enrichment), have Kd values in the range of 64-349 nM toward the target human hepatoma cell HepG2, and also recognize ovarian cancer cells and lung adenocarcinoma. The proteinase treatment experiment indicated that all aptamers could recognize target HepG2 cells through surface proteins. This outcome suggested that these aptamers could be used as potential probes for further research in cancer studies, such as developing early detection assays, targeted therapies, and imaging agents, as well as for the investigation of common membrane proteins in these distinguishable cancers. PMID:25938802

  12. A case of plasmablastic lymphoma of the liver without human immunodeficiency virus infection

    PubMed Central

    Tani, Joji; Miyoshi, Hisaaki; Nomura, Takako; Yoneyama, Hirohito; Kobara, Hideki; Mori, Hirohito; Morishita, Asahiro; Himoto, Takashi; Masaki, Tsutomu

    2013-01-01

    Plasmablastic lymphoma (PBL) is a very rare B-cell lymphoproliferative disorder was with an aggressive clinical behavior that recently characterized by the World Health Organization. Although PBL is most commonly observed in the oral cavity of human immunodeficiency virus (HIV)-positive patients, it can also be observed at extra-oral sites in HIV-negative patients. Epstein-Barr virus (EBV) may be closely related the pathogenesis of PBL. PBL shows different clinicopathological characteristics between HIV-positive and -negative patients. Here, we report a case of PBL of the liver in a 79-year-old HIV-negative male. The patient died approximately 1.5 mo after examination and autopsy showed that the main lesion was a very large liver mass. Histopathological examination of the excised lesion showed large-cell lymphoma with plasmacytic differentiation diffusely infiltrating the liver and involving the surrounding organs. The neoplastic cells were diffusely positive for CD30, EBV, Bob-1, and CD38. The autopsy findings suggested a diagnosis of PBL. To our knowledge, the present case appears to be the first report of PBL with initial presentation of the liver in a patient without HIV infection. PMID:24115831

  13. Anticarcinogenic effects of glycoalkaloids from potatoes against human cervical, liver, lymphoma, and stomach cancer cells.

    PubMed

    Friedman, Mendel; Lee, Kap-Rang; Kim, Hyun-Jeong; Lee, In-Seon; Kozukue, Nobuyuke

    2005-07-27

    Methods were devised for the isolation of large amounts of pure alpha-chaconine and alpha-solanine from Dejima potatoes and for the extraction and analysis of total glycoalkaloids from five fresh potato varieties (Dejima, Jowon, Sumi, Toya, and Vora Valley). These compounds were then evaluated in experiments using a tetrazolium microculture (MTT) assay to assess the anticarcinogenic effects of (a) the isolated pure glycoalkaloids separately, (b) artificial mixtures of the two glycoalkaloids, and (c) the total glycoalkaloids isolated from each of the five potato varieties. All samples tested reduced the numbers of the following human cell lines: cervical (HeLa), liver (HepG2), lymphoma (U937), stomach (AGS and KATO III) cancer cells and normal liver (Chang) cells. The results show that (a) the effects of the glycoalkaloids were concentration dependent in the range of 0.1-10 mug/mL (0.117-11.7 nmol/mL); (b) alpha-chaconine was more active than was alpha-solanine; (c) some mixtures exhibited synergistic effects, whereas other produced additive ones; (d) the different cancer cells varied in their susceptibilities to destruction; and (e) the destruction of normal liver cells was generally lower than that of cancer liver cells. The decreases in cell populations were also observed visually by reversed-phase microscopy. The results complement related observations on the anticarcinogenic potential of food ingredients.

  14. High frequency of Human Cytomegalovirus DNA in the Liver of Infants with Extrahepatic Neonatal Cholestasis

    PubMed Central

    De Tommaso, Adriana MA; Andrade, Paula D; Costa, Sandra CB; Escanhoela, Cecília AF; Hessel, Gabriel

    2005-01-01

    Background Biliary atresia (BA) is the most severe hepatic disorder in newborns and its etiopathogenesis remains unknown. Viral involvement has been proposed, including the human cytomegalovirus (HCMV). The aims of the study were to use the polymerase chain reaction (PCR) to screen the liver tissue of infants with extrahepatic cholestasis for HCMV and to correlate the results with serological antibodies against HCMV and histological findings. Methods A retrospective study in a tertiary care setting included 35 patients (31 BA, 1 BA associated with a choledochal cyst, 2 congenital stenosis of the distal common bile duct and 1 hepatic cyst). HCMV serology was determined by ELISA. Liver and porta hepatis were examined histologically. Liver samples from infants and a control group were screened for HCMV DNA. Results Twelve patients had HCMV negative serology, 9 were positive for IgG antibodies and 14 were positive for IgG and IgM. Nine liver and seven porta hepatis samples were positive for HCMV DNA but none of the control group were positive (general frequency of positivity was 34.3% – 12/35). There was no correlation between HCMV positivity by PCR and the histological findings. The accuracy of serology for detecting HCMV antibodies was low. Conclusion These results indicate an elevated frequency of HCMV in pediatric patients with extrahepatic neonatal cholestasis. They also show the low accuracy of serological tests for detecting active HCMV infection and the lack of correlation between HCMV positivity by PCR and the histopathological changes. PMID:16321152

  15. Constitutive modeling of rate-dependent stress-strain behavior of human liver in blunt impact loading.

    PubMed

    Sparks, Jessica L; Dupaix, Rebecca B

    2008-11-01

    An understanding of the mechanical deformation behavior of the liver under high strain rate loading conditions could aid in the development of vehicle safety measures to reduce the occurrence of blunt liver injury. The purpose of this study was to develop a constitutive model of the stress-strain behavior of the human liver in blunt impact loading. Experimental stress and strain data was obtained from impact tests of 12 unembalmed human livers using a drop tower technique. A constitutive model previously developed for finite strain behavior of amorphous polymers was adapted to model the observed liver behavior. The elements of the model include a nonlinear spring in parallel with a linear spring and nonlinear dashpot. The model captures three features of liver stress-strain behavior in impact loading: (1) relatively stiff initial modulus, (2) rate-dependent yield or rollover to viscous "flow" behavior, and (3) strain hardening at large strains. Six material properties were used to define the constitutive model. This study represents a novel application of polymer mechanics concepts to understand the rate-dependent large strain behavior of human liver tissue under high strain rate loading. Applications of this research include finite element simulations of injury-producing liver or abdominal impact events. PMID:18751900

  16. Hepatic differentiation of human pluripotent stem cells on human liver progenitor HepaRG-derived acellular matrix.

    PubMed

    Kanninen, Liisa K; Porola, Pauliina; Niklander, Johanna; Malinen, Melina M; Corlu, Anne; Guguen-Guillouzo, Christiane; Urtti, Arto; Yliperttula, Marjo L; Lou, Yan-Ru

    2016-02-15

    Human hepatocytes are extensively needed in drug discovery and development. Stem cell-derived hepatocytes are expected to be an improved and continuous model of human liver to study drug candidates. Generation of endoderm-derived hepatocytes from human pluripotent stem cells (hPSCs), including human embryonic stem cells and induced pluripotent stem cells, is a complex, challenging process requiring specific signals from soluble factors and insoluble matrices at each developmental stage. In this study, we used human liver progenitor HepaRG-derived acellular matrix (ACM) as a hepatic progenitor-specific matrix to induce hepatic commitment of hPSC-derived definitive endoderm (DE) cells. The DE cells showed much better attachment to the HepaRG ACM than other matrices tested and then differentiated towards hepatic cells, which expressed hepatocyte-specific makers. We demonstrate that Matrigel overlay induced hepatocyte phenotype and inhibited biliary epithelial differentiation in two hPSC lines studied. In conclusion, our study demonstrates that the HepaRG ACM, a hepatic progenitor-specific matrix, plays an important role in the hepatic differentiation of hPSCs.

  17. The metabolism of trifluoperazine (TFP) exhibits atypical kinetic behavior in both human liver microsomes (HLMs) and monkey liver microsomes (MyLM).

    PubMed

    Xiao, Jin-Fang; Liu, Xiao-Jun; Liu, Gao-Wang; Yang, Xue-Ying; Xiao, Pan; Hou, Xiao-Min; Wang, Hai-Tang; Tang, Jian-Jun; Zhang, Ya-Ting; Zhen, Chen; Fang, Hai-Hong

    2014-12-01

    Glucuronidation reaction of trifluoperazine (TFP) is a typical probe reaction to phenotype the activity of UDP-glucuronosyltransferase 1A4. The present study aims to compare the metabolic behavior of TFP in the liver microsomes from human and cynomolgus monkey, including the kinetic type and parameters. In vitro human liver microsome incubation system was used. The Eadie-Hofstee plot was used to determine the kinetic type. The results showed that the data for human liver microsomes (HLMs) and monkey liver microsomes (MyLMs)-catalyzed glucuronidation were best fit to the substrate inhibition model. For the metabolism of TFP in HLMs, the kinetic parameters were calculated to be 40 ± 5 and 140 ± 20 μM for K m and K si values, respectively. For the MyLM-mediated metabolism of TFP, the K m and K si values were calculated to be 108 ± 10 and 250 ± 30 μM, respectively. The same metabolic kinetic type and different kinetic parameters were demonstrated for the metabolism of TFP between HLMs and MyLMs. All these data were helpful for understanding the metabolism difference of TFP between human and monkey.

  18. Gene expression analysis of precision-cut human liver slices indicates stable expression of ADME-Tox related genes

    SciTech Connect

    Elferink, M.G.L.; Olinga, P.; van Leeuwen, E.M.; Bauerschmidt, S.; Polman, J.; Schoonen, W.G.; Heisterkamp, S.H.; Groothuis, G.M.M.

    2011-05-15

    In the process of drug development it is of high importance to test the safety of new drugs with predictive value for human toxicity. A promising approach of toxicity testing is based on shifts in gene expression profiling of the liver. Toxicity screening based on animal liver cells cannot be directly extrapolated to humans due to species differences. The aim of this study was to evaluate precision-cut human liver slices as in vitro method for the prediction of human specific toxicity by toxicogenomics. The liver slices contain all cell types of the liver in their natural architecture. This is important since drug-induced toxicity often is a multi-cellular process. Previously we showed that toxicogenomic analysis of rat liver slices is highly predictive for rat in vivo toxicity. In this study we investigated the levels of gene expression during incubation up to 24 h with Affymetrix microarray technology. The analysis was focused on a broad spectrum of genes related to stress and toxicity, and on genes encoding for phase-I, -II and -III metabolizing enzymes and transporters. Observed changes in gene expression were associated with cytoskeleton remodeling, extracellular matrix and cell adhesion, but for the ADME-Tox related genes only minor changes were observed. PCA analysis showed that changes in gene expression were not associated with age, sex or source of the human livers. Slices treated with acetaminophen showed patterns of gene expression related to its toxicity. These results indicate that precision-cut human liver slices are relatively stable during 24 h of incubation and represent a valuable model for human in vitro hepatotoxicity testing despite the human inter-individual variability.

  19. Human liver alcohol dehydrogenase. 2. The primary structure of the gamma 1 protein chain.

    PubMed

    Bühler, R; Hempel, J; Kaiser, R; de Zalenski, C; von Wartburg, J P; Jörnvall, H

    1984-12-17

    The primary structure of the gamma 1 subunit of human liver alcohol dehydrogenase isoenzyme gamma 1 gamma 1 was deduced by characterization of 36 tryptic and 2 CNBr peptides. The polypeptide chain is composed of 373 amino acid residues. gamma 1 differs from the beta 1 subunit of human liver alcohol dehydrogenase at 21 positions, and from the E subunit of horse liver alcohol dehydrogenase at 43 positions including a gap at position 128 as in the beta 1 subunit. All zinc-liganding residues from the E subunit of the horse protein and the beta 1 subunit of the human enzyme are conserved, but like beta 1, gamma 1 also has an additional cysteine residue at position 286 (in the positional numbering system of the horse enzyme) due to a Tyr----Cys exchange. Most amino acid exchanges preserve the properties of the residues affected and are largely located on the surface of the molecules, away from the active site and the coenzyme binding region. However, eight positions with charge differences in relation to the E subunit of the horse enzyme are noticed. These result in a net positive charge increase of one in gamma 1 versus E, explaining the electrophoretic mobilities on starch gels. Of functional significance is the conservation of Ser-48 in gamma 1 relative to E. The residue is close to the active site but different (Thr-48) in the beta 1 subunit of the human enzyme. Thus, the closer structural relationship between human gamma 1 and horse E enzyme subunit than between beta 1 and E is also reflected in functionally important residues, explaining a greater similarity between gamma 1 gamma 1 and EE than between beta 1 beta 1 and EE. PMID:6391921

  20. Three-dimensional culture of human embryonic stem cell derived hepatic endoderm and its role in bioartificial liver construction.

    PubMed

    Sharma, Ruchi; Greenhough, Sebastian; Medine, Claire N; Hay, David C

    2010-01-01

    The liver carries out a range of functions essential for bodily homeostasis. The impairment of liver functions has serious implications and is responsible for high rates of patient morbidity and mortality. Presently, liver transplantation remains the only effective treatment, but donor availability is a major limitation. Therefore, artificial and bioartificial liver devices have been developed to bridge patients to liver transplantation. Existing support devices improve hepatic encephalopathy to a certain extent; however their usage is associated with side effects. The major hindrance in the development of bioartificial liver devices and cellular therapies is the limited availability of human hepatocytes. Moreover, primary hepatocytes are difficult to maintain and lose hepatic identity and function over time even with sophisticated tissue culture media. To overcome this limitation, renewable cell sources are being explored. Human embryonic stem cells are one such cellular resource and have been shown to generate a reliable and reproducible supply of human hepatic endoderm. Therefore, the use of human embryonic stem cell-derived hepatic endoderm in combination with tissue engineering has the potential to pave the way for the development of novel bioartificial liver devices and predictive drug toxicity assays.

  1. Three-Dimensional Culture of Human Embryonic Stem Cell Derived Hepatic Endoderm and Its Role in Bioartificial Liver Construction

    PubMed Central

    Sharma, Ruchi; Greenhough, Sebastian; Medine, Claire N.; Hay, David C.

    2010-01-01

    The liver carries out a range of functions essential for bodily homeostasis. The impairment of liver functions has serious implications and is responsible for high rates of patient morbidity and mortality. Presently, liver transplantation remains the only effective treatment, but donor availability is a major limitation. Therefore, artificial and bioartificial liver devices have been developed to bridge patients to liver transplantation. Existing support devices improve hepatic encephalopathy to a certain extent; however their usage is associated with side effects. The major hindrance in the development of bioartificial liver devices and cellular therapies is the limited availability of human hepatocytes. Moreover, primary hepatocytes are difficult to maintain and lose hepatic identity and function over time even with sophisticated tissue culture media. To overcome this limitation, renewable cell sources are being explored. Human embryonic stem cells are one such cellular resource and have been shown to generate a reliable and reproducible supply of human hepatic endoderm. Therefore, the use of human embryonic stem cell-derived hepatic endoderm in combination with tissue engineering has the potential to pave the way for the development of novel bioartificial liver devices and predictive drug toxicity assays. PMID:20169088

  2. Laser induced breakdown spectroscopy of human liver samples with Wilson's disease

    NASA Astrophysics Data System (ADS)

    Grolmusová, Zuzana; Horňáčková, Michaela; Plavčan, Jozef; Kopáni, Martin; Babál, Pavel; Veis, Pavel

    2013-08-01

    Laser induced breakdown spectroscopy (LIBS) is an elemental analytical technique with various applications. The paper demonstrates the first LIBS measurements of human liver samples for the purpose of detecting the higher copper content related with the advanced stage of Wilson's disease. These measurements were implemented using a Nd:YAG laser working at the wavelength of 532 nm and an echelle type spectrometer equipped with an intensified CCD camera allowing for a wide spectral range coverage (200-950 nm) and rapid camera gating (minimum gating time of 5 ns). Seven liver samples with suspected Wilson's disease and five reference samples were investigated. The main parameter of interest was the Cu/C ratio obtained at first from spectra and secondly directly from an iCCD image. Our experiment is a pilot study, which shows LIBS analysis of human liver samples for the purpose of detecting the normal and higher copper content for the first time. The method proved to be a quick and a low-cost approach for the detection of pathological accumulation of copper in the affected tissue.

  3. Butyltin residues in livers of humans and wild terrestrial mammals and in plastic products.

    PubMed

    Takahashi, S; Mukai, H; Tanabe, S; Sakayama, K; Miyazaki, T; Masuno, H

    1999-08-01

    Butyltin compounds (BTs) including mono-(MBT), di-(DBT) and tributyltin (TBT) were determined in livers of humans and wild terrestrial mammals, such as raccoon dogs (Nyctereutes procyonoids) and monkeys (Macaca fuscata) from Japan. In addition, 22 samples of plastic products were analyzed. BT residues were detected in all the liver samples of humans and raccoon dogs, with concentrations of <360 ng/g wet wt, whereas concentrations in the liver of monkeys were either less than the detection limit or were only in trace levels. Elevated concentrations of BTs, particularly DBT (<140,000 ng/g) and MBT (<130,000 ng/g), were found in some plastic products, such as baking parchments made from siliconized paper and gloves made up from polyurethane. The results of a cooking test using the above baking parchment indicated the transfer of BTs to foodstuffs. These observations suggest expansion of BT contamination among terrestrial mammals. BT pollution from industrial appliances, such as plastic stabilizers and catalysts other than those of marine origin as antifouling agents, are suggested as alternative sources of exposure.

  4. Anti-hepatitis C virus potency of a new autophagy inhibitor using human liver slices model

    PubMed Central

    Lagaye, Sylvie; Brun, Sonia; Gaston, Jesintha; Shen, Hong; Stranska, Ruzena; Camus, Claire; Dubray, Clarisse; Rousseau, Géraldine; Massault, Pierre-Philippe; Courcambeck, Jerôme; Bassisi, Firas; Halfon, Philippe; Pol, Stanislas

    2016-01-01

    AIM: To evaluate the antiviral potency of a new anti-hepatitis C virus (HCV) antiviral agent targeting the cellular autophagy machinery. METHODS: Non-infected liver slices, obtained from human liver resection and cut in 350 μm-thick slices (2.7 × 106 cells per slice) were infected with cell culture-grown HCV Con1b/C3 supernatant (multiplicity of infection = 0.1) cultivated for up to ten days. HCV infected slices were treated at day 4 post-infection with GNS-396 for 6 d at different concentrations. HCV replication was evaluated by strand-specific real-time quantitative reverse transcription - polymerase chain reaction. The infectivity titers of supernatants were evaluated by foci formation upon inoculation into naive Huh-7.5.1 cells. The cytotoxic effect of the drugs was evaluated by lactate dehydrogenase leakage assays. RESULTS: The antiviral efficacy of a new antiviral drug, GNS-396, an autophagy inhibitor, on HCV infection of adult human liver slices was evidenced in a dose-dependent manner. At day 6 post-treatment, GNS-396 EC50 was 158 nmol/L without cytotoxic effect (compared to hydroxychloroquine EC50 = 1.17 μmol/L). CONCLUSION: Our results demonstrated that our ex vivo model is efficient for evaluation the potency of autophagy inhibitors, in particular a new quinoline derivative GNS-396 as antiviral could inhibit HCV infection in a dose-dependent manner without cytotoxic effect. PMID:27478540

  5. The mechanical response of human liver and its relation to histology: an in vivo study.

    PubMed

    Mazza, Edoardo; Nava, Alessandro; Hahnloser, Dieter; Jochum, Wolfram; Bajka, Michael

    2007-12-01

    The mechanical response of human liver is characterized in vivo by means of intra-operative aspiration experiments. Mechanical characterization is combined with histological evaluation of liver tissue biopsies obtained from the resected liver at the site of mechanical testing. This procedure enables a quantitative analysis of the correlation between mechanical response and tissue micro-structure of normal and diseased liver. Ten organs were tested in vivo at multiple locations, as well as ex vivo immediately after resection. Biopsies were analyzed in terms of pathology and percentage of connective tissue content. The change of the mechanical parameters from in vivo to ex vivo has been determined, with an increase of 17% of the proposed stiffness index. The relationship between mechanical parameters and various pathologic conditions affecting the tissue samples has been quantified, with fibrosis leading to a response up to three times stiffer as compared with normal tissue. Increased stiffness can be detected by digital palpation (increased "consistency") and may suggest the presence of a tumor. The present observations suggest that stiffness increase cannot be attributed to the tumoral tissue itself, but rather to the fibrotic stroma that often arise within or adjacent to the tumor. Variation of the mechanical parameters as a function of connective tissue content has been evaluated based on the histological examinations and the results confirm a direct proportionality between stiffness index and connective tissue percentage. The approach described here might eventually lead to a diagnostic procedure and complement other clinical methods, like palpation and ultrasound examination of the liver. PMID:17719834

  6. Chimeric mice with hepatocyte-humanized liver as an appropriate model to study human peroxisome proliferator-activated receptor-α.

    PubMed

    Tateno, Chise; Yamamoto, Toshinobu; Utoh, Rie; Yamasaki, Chihiro; Ishida, Yuji; Myoken, Yuka; Oofusa, Ken; Okada, Miyoko; Tsutsui, Naohisa; Yoshizato, Katsutoshi

    2015-02-01

    Peroxisome proliferator (PP)-activated receptor-α (PPARα) agonists exhibit species-specific effects on livers of the rodent and human (h), which has been considered to reside in the difference of PPARα gene structures. However, the contribution of h-hepatocytes (heps) to the species-specificity remains to be clarified. In this study, the effects of fenofibrate were investigated using a hepatocyte-humanized chimeric mouse (m) model whose livers were replaced with h-heps at >70%. Fenofibrate induced hepatocellular hypertrophy, cell proliferation, and peroxisome proliferation in livers of severe combined immunodeficiency (SCID) mice, but not in the h-hep of chimeric mouse livers. Fenofibrate increased the expression of the enzymes of β- and ω-hydroxylation and deoxygenation of lipids at both gene and protein levels in SCID mouse livers, but not in the h-heps of chimeric mouse livers, supporting the studies with h-PPARα-transgenic mice, a hitherto reliable model for studying the regulation of h-PPARα in the h-liver in most respects, except the induction of the peroxisome proliferation. This study indicates the importance of not only h-PPARα gene but also h-heps themselves to correctly predict effects of fibrates on h-livers, and, therefore, suggests that the chimeric mouse is a currently available, consistent, and reliable model to obtain pharmaceutical data concerning the effects of fibrates on h-livers.

  7. Basic investigation on acoustic velocity change imaging method for quantitative assessment of fat content in human liver

    NASA Astrophysics Data System (ADS)

    Mano, Kazune; Tanigawa, Shohei; Hori, Makoto; Yokota, Daiki; Wada, Kenji; Matsunaka, Toshiyuki; Morikawa, Hiroyasu; Horinaka, Hiromichi

    2016-07-01

    Fatty liver is a disease caused by the excess accumulation of fat in the human liver. The early diagnosis of fatty liver is very important, because fatty liver is the major marker linked to metabolic syndrome. We already proposed the ultrasonic velocity change imaging method to diagnose fatty liver by using the fact that the temperature dependence of ultrasonic velocity is different in water and in fat. For the diagonosis of a fatty liver stage, we attempted a feasibility study of the quantitative assessment of the fat content in the human liver using our ultrasonic velocity change imaging method. Experimental results showed that the fat content in the tissue mimic phantom containing lard was determined by its ultrasonic velocity change in the flat temperature region formed by a circular warming ultrasonic transducer with an acoustic lens having an appropriate focal length. By considering the results of our simulation using a thermal diffusion equation, we determined whether this method could be applied to fatty liver assessment under the condition that the tissue had the thermal relaxation effect caused by blood flow.

  8. Liver X receptor activation stimulates iron export in human alternative macrophages

    PubMed Central

    Bories, Gael; Colin, Sophie; Vanhoutte, Jonathan; Derudas, Bruno; Copin, Corinne; Fanchon, Melanie; Daoudi, Mehdi; Belloy, Loic; Haulon, Stephan; Zawadzki, Christophe; Jude, Brigitte; Staels, Bart; Chinetti-Gbaguidi, Giulia

    2013-01-01

    Rationale In atherosclerotic plaques, iron preferentially accumulates in macrophages where it can exert pro-oxidant activities. Objective The objective of this study is, first, to better characterize the iron distribution and metabolism in macrophage sub-populations in human atherosclerotic plaques and, second, to determine whether iron homeostasis is under the control of nuclear receptors, such as the Liver X Receptors (LXR). Methods and Results Here we report that iron depots accumulate in human atherosclerotic plaque areas enriched in CD68 and Mannose Receptor (MR) positive (CD68+MR+) alternative M2 macrophages. In vitro IL-4 polarization of human monocytes into M2 macrophages also resulted in a gene expression profile and phenotype favouring iron accumulation. However, upon iron exposure, M2 macrophages acquire a phenotype favouring iron release, through a strong increase in ferroportin expression, illustrated by a more avid oxidation of extra-cellular LDL by iron-loaded M2 macrophages. In line, in human atherosclerotic plaques, CD68+MR+ macrophages accumulate oxidized lipids, which activate Liver X Receptors (LXRα and LXRβ), resulting in the induction of ABCA1, ABCG1 and ApoE expression. Moreover, in iron-loaded M2 macrophages, LXR activation induces nuclear factor erythroid 2-like 2 (NRF2) expression, hence increasing ferroportin expression, which, together with a decrease of hepcidin mRNA levels, promotes iron export. Conclusions These data identify a role for M2 macrophages in iron handling, a process which is regulated by LXR activation. PMID:24036496

  9. From the Cover: Cell-replacement therapy for diabetes: Generating functional insulin-producing tissue from adult human liver cells

    NASA Astrophysics Data System (ADS)

    Sapir, Tamar; Shternhall, Keren; Meivar-Levy, Irit; Blumenfeld, Tamar; Cohen, Hamutal; Skutelsky, Ehud; Eventov-Friedman, Smadar; Barshack, Iris; Goldberg, Iris; Pri-Chen, Sarah; Ben-Dor, Lya; Polak-Charcon, Sylvie; Karasik, Avraham; Shimon, Ilan; Mor, Eytan; Ferber, Sarah

    2005-05-01

    Shortage in tissue availability from cadaver donors and the need for life-long immunosuppression severely restrict the large-scale application of cell-replacement therapy for diabetic patients. This study suggests the potential use of adult human liver as alternate tissue for autologous beta-cell-replacement therapy. By using pancreatic and duodenal homeobox gene 1 (PDX-1) and soluble factors, we induced a comprehensive developmental shift of adult human liver cells into functional insulin-producing cells. PDX-1-treated human liver cells express insulin, store it in defined granules, and secrete the hormone in a glucose-regulated manner. When transplanted under the renal capsule of diabetic, immunodeficient mice, the cells ameliorated hyperglycemia for prolonged periods of time. Inducing developmental redirection of adult liver offers the potential of a cell-replacement therapy for diabetics by allowing the patient to be the donor of his own insulin-producing tissue. pancreas | transdifferentiation

  10. CXCR6 marks a novel subset of T-bet(lo)Eomes(hi) natural killer cells residing in human liver.

    PubMed

    Stegmann, Kerstin A; Robertson, Francis; Hansi, Navjyot; Gill, Upkar; Pallant, Celeste; Christophides, Theodoros; Pallett, Laura J; Peppa, Dimitra; Dunn, Claire; Fusai, Giuseppe; Male, Victoria; Davidson, Brian R; Kennedy, Patrick; Maini, Mala K

    2016-05-23

    Natural killer cells (NK) are highly enriched in the human liver, where they can regulate immunity and immunopathology. We probed them for a liver-resident subset, distinct from conventional bone-marrow-derived NK. CXCR6+ NK were strikingly enriched in healthy and diseased liver compared to blood (p < 0.0001). Human hepatic CXCR6+ NK had an immature phenotype (predominantly CD56(bright)CD16-CD57-), and expressed the tissue-residency marker CD69. CXCR6+ NK produced fewer cytotoxic mediators and pro-inflammatory cytokines than the non-liver-specific CXCR6- fraction. Instead CXCR6+ NK could upregulate TRAIL, a key death ligand in hepatitis pathogenesis. CXCR6 demarcated liver NK into two transcriptionally distinct populations: T-bet(hi)Eomes(lo)(CXCR6-) and T-bet(lo)Eomes(hi)(CXCR6+); the latter was virtually absent in the periphery. The small circulating CXCR6+ subset was predominantly T-bet(hi)Eomes(lo), suggesting its lineage was closer to CXCR6- peripheral than CXCR6+ liver NK. These data reveal a large subset of human liver-resident T-bet(lo)Eomes(hi) NK, distinguished by their surface expression of CXCR6, adapted for hepatic tolerance and inducible anti-viral immunity.

  11. Spontaneous origin from human embryonic stem cells of liver cells displaying conjoint meso-endodermal phenotype with hepatic functions

    PubMed Central

    Bandi, Sriram; Cheng, Kang; Joseph, Brigid; Gupta, Sanjeev

    2012-01-01

    Understanding the identity of lineage-specific cells arising during manipulations of stem cells is necessary for developing their potential applications. For instance, replacement of crucial functions in organ failure by transplantation of suitable stem-cell-derived cells will be applicable to numerous disorders, but requires insights into the origin, function and fate of specific cell populations. We studied mechanisms by which the identity of differentiated cells arising from stem cells could be verified in the context of natural liver-specific stem cells and whether such differentiated cells could be effective for supporting the liver following cell therapy in a mouse model of drug-induced acute liver failure. By comparing the identity of naturally occurring fetal human liver stem cells, we found that cells arising in cultures of human embryonic stem cells (hESCs) recapitulated an early fetal stage of liver cells, which was characterized by conjoint meso-endoderm properties. Despite this fetal stage, hESC-derived cells could provide liver support with appropriate metabolic and ammonia-fixation functions, as well as cytoprotection, such that mice were rescued from acute liver failure. Therefore, spontaneous or induced differentiation of human embryonic stem cells along the hepatic endoderm will require transition through fetal-like stages. This offers opportunities to prospectively identify whether suitable cells have been generated through manipulation of stem cells for cell therapy and other applications. PMID:22349702

  12. CXCR6 marks a novel subset of T-bet(lo)Eomes(hi) natural killer cells residing in human liver.

    PubMed

    Stegmann, Kerstin A; Robertson, Francis; Hansi, Navjyot; Gill, Upkar; Pallant, Celeste; Christophides, Theodoros; Pallett, Laura J; Peppa, Dimitra; Dunn, Claire; Fusai, Giuseppe; Male, Victoria; Davidson, Brian R; Kennedy, Patrick; Maini, Mala K

    2016-01-01

    Natural killer cells (NK) are highly enriched in the human liver, where they can regulate immunity and immunopathology. We probed them for a liver-resident subset, distinct from conventional bone-marrow-derived NK. CXCR6+ NK were strikingly enriched in healthy and diseased liver compared to blood (p < 0.0001). Human hepatic CXCR6+ NK had an immature phenotype (predominantly CD56(bright)CD16-CD57-), and expressed the tissue-residency marker CD69. CXCR6+ NK produced fewer cytotoxic mediators and pro-inflammatory cytokines than the non-liver-specific CXCR6- fraction. Instead CXCR6+ NK could upregulate TRAIL, a key death ligand in hepatitis pathogenesis. CXCR6 demarcated liver NK into two transcriptionally distinct populations: T-bet(hi)Eomes(lo)(CXCR6-) and T-bet(lo)Eomes(hi)(CXCR6+); the latter was virtually absent in the periphery. The small circulating CXCR6+ subset was predominantly T-bet(hi)Eomes(lo), suggesting its lineage was closer to CXCR6- peripheral than CXCR6+ liver NK. These data reveal a large subset of human liver-resident T-bet(lo)Eomes(hi) NK, distinguished by their surface expression of CXCR6, adapted for hepatic tolerance and inducible anti-viral immunity. PMID:27210614

  13. The immunophenotype of antigen presenting cells of the mononuclear phagocyte system in normal human liver--a systematic review.

    PubMed

    Strauss, Otto; Dunbar, P Rod; Bartlett, Adam; Phillips, Anthony

    2015-02-01

    The mononuclear phagocytic system (MPS), comprised of monocytes, macrophages, and dendritic cells, is essential in tissue homeostasis and in determining the balance of the immune response through its role in antigen presentation. It has been identified as a therapeutic target in infectious disease, cancer, autoimmune disease and transplant rejection. Here, we review the current understanding of the immunophenotype and function of the MPS in normal human liver. Using well-defined selection criteria, a search of MEDLINE and EMBASE databases identified 76 appropriate studies. The majority (n=67) described Kupffer cells (KCs), although the definition of KC differs between sources, and little data were available regarding their function. Only 10 papers looked at liver dendritic cells (DCs), and largely confirmed the presence of the major dendritic cell subsets identified in human blood. Monocytes were thoroughly characterized in four studies that utilized flow cytometry and fluorescent microscopy and highlighted their prominent role in liver homeostasis and displayed subtle differences from circulating monocytes. There was some limited evidence that liver DCs are tolerogenic but neither liver dendritic cell subsets nor macrophages have been thoroughly characterized, using either multi-colour flow cytometry or multi-parameter fluorescence microscopy. The lobular distribution of different subsets of liver MPS cells was also poorly described, and the ability to distinguish between passenger leukocytes and tissue resident cells remains limited. It was apparent that further research, using modern immunological techniques, is now required to accurately characterize the cells of the MPS in human liver.

  14. Molecular biomarkers for aflatoxins and their application to human liver cancer.

    PubMed

    Scholl, P; Musser, S M; Kensler, T W; Groopman, J D

    1995-01-01

    The rationale for developing molecular biomarkers to monitor and assess risk from human exposure to aflatoxins have been justified by the association of these carcinogens with human liver cancer, a disease that causes at least 250000 deaths world-wide each year. The goal of our research has been the development of aflatoxin biomarkers based upon the knowledge of the biochemistry and toxicology of aflatoxins gleaned from both experimental and human studies. These biomarkers have been subsequently utilized in experimental chemoprotection models to provide data on the modulation of these markers under different situations of disease risk. Several of the aflatoxin specific biomarkers have been validated in epidemiologic studies and are now available to use as intermediate biomarkers in chemoprotection trials. This systematic approach provides encouragement for preventive interventions and should serve as a template for the development, validation and application of other chemical-specific biomarkers to cancer or other chronic diseases.

  15. Xmrk, kras and myc transgenic zebrafish liver cancer models share molecular signatures with subsets of human hepatocellular carcinoma.

    PubMed

    Zheng, Weiling; Li, Zhen; Nguyen, Anh Tuan; Li, Caixia; Emelyanov, Alexander; Gong, Zhiyuan

    2014-01-01

    Previously three oncogene transgenic zebrafish lines with inducible expression of xmrk, kras or Myc in the liver have been generated and these transgenic lines develop oncogene-addicted liver tumors upon chemical induction. In the current study, comparative transcriptomic approaches were used to examine the correlation of the three induced transgenic liver cancers with human liver cancers. RNA profiles from the three zebrafish tumors indicated relatively small overlaps of significantly deregulated genes and biological pathways. Nevertheless, the three transgenic tumor signatures all showed significant correlation with advanced or very advanced human hepatocellular carcinoma (HCC). Interestingly, molecular signature from each oncogene-induced zebrafish liver tumor correlated with only a small subset of human HCC samples (24-29%) and there were conserved up-regulated pathways between the zebrafish and correlated human HCC subgroup. The three zebrafish liver cancer models together represented nearly half (47.2%) of human HCCs while some human HCCs showed significant correlation with more than one signature defined from the three oncogene-addicted zebrafish tumors. In contrast, commonly deregulated genes (21 up and 16 down) in the three zebrafish tumor models generally showed accordant deregulation in the majority of human HCCs, suggesting that these genes might be more consistently deregulated in a broad range of human HCCs with different molecular mechanisms and thus serve as common diagnosis markers and therapeutic targets. Thus, these transgenic zebrafish models with well-defined oncogene-induced tumors are valuable tools for molecular classification of human HCCs and for understanding of molecular drivers in hepatocarcinogenesis in each human HCC subgroup.

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

    PubMed Central

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

    2015-01-01

    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 × 106 KC, 2.7 × 105 LEC and 4.7 × 105 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

  17. Systematic genetic and genomic analysis of cytochrome P450 enzyme activities in human liver

    PubMed Central

    Yang, Xia; Zhang, Bin; Molony, Cliona; Chudin, Eugene; Hao, Ke; Zhu, Jun; Gaedigk, Andrea; Suver, Christine; Zhong, Hua; Leeder, J. Steven; Guengerich, F. Peter; Strom, Stephen C.; Schuetz, Erin; Rushmore, Thomas H.; Ulrich, Roger G.; Slatter, J. Greg; Schadt, Eric E.; Kasarskis, Andrew; Lum, Pek Yee

    2010-01-01

    Liver cytochrome P450s (P450s) play critical roles in drug metabolism, toxicology, and metabolic processes. Despite rapid progress in the understanding of these enzymes, a systematic investigation of the full spectrum of functionality of individual P450s, the interrelationship or networks connecting them, and the genetic control of each gene/enzyme is lacking. To this end, we genotyped, expression-profiled, and measured P450 activities of 466 human liver samples and applied a systems biology approach via the integration of genetics, gene expression, and enzyme activity measurements. We found that most P450s were positively correlated among themselves and were highly correlated with known regulators as well as thousands of other genes enriched for pathways relevant to the metabolism of drugs, fatty acids, amino acids, and steroids. Genome-wide association analyses between genetic polymorphisms and P450 expression or enzyme activities revealed sets of SNPs associated with P450 traits, and suggested the existence of both cis-regulation of P450 expression (especially for CYP2D6) and more complex trans-regulation of P450 activity. Several novel SNPs associated with CYP2D6 expression and enzyme activity were validated in an independent human cohort. By constructing a weighted coexpression network and a Bayesian regulatory network, we defined the human liver transcriptional network structure, uncovered subnetworks representative of the P450 regulatory system, and identified novel candidate regulatory genes, namely, EHHADH, SLC10A1, and AKR1D1. The P450 subnetworks were then validated using gene signatures responsive to ligands of known P450 regulators in mouse and rat. This systematic survey provides a comprehensive view of the functionality, genetic control, and interactions of P450s. PMID:20538623

  18. Engineering a perfusable 3D human liver platform from iPS cells.

    PubMed

    Schepers, Arnout; Li, Cheri; Chhabra, Arnav; Seney, Benjamin Tschudy; Bhatia, Sangeeta

    2016-07-01

    In vitro models of human tissue are crucial to our ability to study human disease as well as develop safe and effective drug therapies. Models of single organs in static and microfluidic culture have been established and shown utility for modeling some aspects of health and disease; however, these systems lack multi-organ interactions that are critical to some aspects of drug metabolism and toxicity. Thus, as part of a consortium of researchers, we have developed a liver chip that meets the following criteria: (1) employs human iPS cells from a patient of interest, (2) cultures cells in perfusable 3D organoids, and (3) is robust to variations in perfusion rate so as to be compatible in series with other specialized tissue chips (e.g. heart, lung). In order to achieve this, we describe methods to form hepatocyte aggregates from primary and iPS-derived cells, alone and in co-culture with support cells. This necessitated a novel culture protocol for the interrupted differentiation of iPS cells that permits their removal from a plated surface and aggregation while maintaining phenotypic hepatic functions. In order to incorporate these 3D aggregates in a perfusable platform, we next encapsulated the cells in a PEG hydrogel to prevent aggregation and overgrowth once on chip. We adapted a C-trap chip architecture from the literature that enabled robust loading with encapsulated organoids and culture over a range of flow rates. Finally, we characterize the liver functions of this iHep organoid chip under perfusion and demonstrate a lifetime of at least 28 days. We envision that such this strategy can be generalized to other microfluidic tissue models and provides an opportunity to query patient-specific liver responses in vitro.

  19. Engineering a perfusable 3D human liver platform from iPS cells.

    PubMed

    Schepers, Arnout; Li, Cheri; Chhabra, Arnav; Seney, Benjamin Tschudy; Bhatia, Sangeeta

    2016-07-01

    In vitro models of human tissue are crucial to our ability to study human disease as well as develop safe and effective drug therapies. Models of single organs in static and microfluidic culture have been established and shown utility for modeling some aspects of health and disease; however, these systems lack multi-organ interactions that are critical to some aspects of drug metabolism and toxicity. Thus, as part of a consortium of researchers, we have developed a liver chip that meets the following criteria: (1) employs human iPS cells from a patient of interest, (2) cultures cells in perfusable 3D organoids, and (3) is robust to variations in perfusion rate so as to be compatible in series with other specialized tissue chips (e.g. heart, lung). In order to achieve this, we describe methods to form hepatocyte aggregates from primary and iPS-derived cells, alone and in co-culture with support cells. This necessitated a novel culture protocol for the interrupted differentiation of iPS cells that permits their removal from a plated surface and aggregation while maintaining phenotypic hepatic functions. In order to incorporate these 3D aggregates in a perfusable platform, we next encapsulated the cells in a PEG hydrogel to prevent aggregation and overgrowth once on chip. We adapted a C-trap chip architecture from the literature that enabled robust loading with encapsulated organoids and culture over a range of flow rates. Finally, we characterize the liver functions of this iHep organoid chip under perfusion and demonstrate a lifetime of at least 28 days. We envision that such this strategy can be generalized to other microfluidic tissue models and provides an opportunity to query patient-specific liver responses in vitro. PMID:27296616

  20. 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.

  1. Detection of anti-liver cell membrane antibody using a human hepatocellular carcinoma cell line

    SciTech Connect

    Lobo-Yeo, A.; McSorley, C.; McFarlane, B.M.; Mieli-Vergani, G.; Mowat, A.P.; Vergani, D.

    1989-02-01

    A radioimmunometric technique for the detection of autoantibodies to liver membrane antigens has been developed using Alexander cells, a human hepatocellular carcinoma cell line. After incubation of Alexander cells with serum, antimembrane antibodies were detected by addition of /sup 125/I-labeled Protein A. Binding ratios in 15 children with uncontrolled autoimmune chronic active hepatitis and in seven children with primary sclerosing cholangitis were significantly higher than in 18 age-matched normal controls. Nine patients with inactive autoimmune chronic active hepatitis, 13 with alpha 1-antitrypsin deficiency and five with fulminant hepatic failure had ratios similar to controls. In nine patients with Wilson's disease, there was a modest but significant increase in binding ratio. In four children with autoimmune chronic active hepatitis, binding ratios fell during effective immunosuppressive therapy. Sera from patients with systemic lupus erythematosus or rheumatoid arthritis gave normal results, excluding that binding derives from Fc-mediated immune complex capture. A positive correlation was found between Alexander cell binding values and anti-liver-specific protein antibody titers, suggesting that the two assays detect antibodies against shared antigenic determinants. The Alexander cell assay is a simple, rapid and sensitive technique to detect antibody to liver cell membrane antigens.

  2. Human liver alcohol dehydrogenase. 1. The primary structure of the beta 1 beta 1 isoenzyme.

    PubMed

    Hempel, J; Bühler, R; Kaiser, R; Holmquist, B; de Zalenski, C; von Wartburg, J P; Vallee, B; Jörnvall, H

    1984-12-17

    Determination of the amino acid sequence of the beta 1 subunit from the class I (pyrazole-sensitive) human liver alcohol dehydrogenase isoenzyme beta 1 beta 1 revealed a 373-residue structure differing at 48 positions (including a gap) from that of the subunit of the well studied horse liver alcohol dehydrogenase EE isoenzyme. The structure deduced is compatible with known differences in composition, ultraviolet absorbance, electrophoretic mobility and catalytic properties between the horse and human enzymes. All zinc-liganding residues of the horse E subunit are strictly conserved in the human beta 1 subunit, despite an earlier report of a mutation involving Cys-46. This residue therefore remains conserved in all known alcohol dehydrogenase structures. However, the total cysteine content of the beta 1 structure is raised from 14 in the subunit of the horse enzyme to 15 by a Tyr----Cys exchange. Most exchanges are on the surface of the molecule and of a well conserved nature. Substitutions close to the catalytic centre are of interest to explain the altered substrate specificity and different catalytic activity of the beta 1 homodimer. Functionally, a Ser----Thr exchange at position 48 appears to be of special importance, since Thr-48 in beta 1 instead of Ser-48 in the horse enzyme can restrict available space. Four other substitutions also line the active-site pocket, and appear to constitute partly compensated exchanges. PMID:6391920

  3. Mechanisms of Tissue–Iron Relaxivity: Nuclear Magnetic Resonance Studies of Human Liver Biopsy Specimens

    PubMed Central

    Ghugre, Nilesh R.; Coates, Thomas D.; Nelson, Marvin D.; Wood, John C.

    2010-01-01

    MRI is becoming an increasingly important tool to assess iron overload disorders, but the complex nature of proton–iron interactions has troubled noninvasive iron quantification. Intersite and intersequence variability as well as methodological inaccuracies have been limiting factors to its widespread clinical use. It is important to understand the underlying proton relaxation mechanisms within the (human) tissue environment to address these differences. In this respect, NMR relaxometry was performed on 10 fresh human liver biopsy specimens taken from patients with transfusion-dependent anemia. T1 (1/R1) inversion recovery, T2 (1/R2) single echo, and multiecho T2 CPMG measurements were performed on a 60-MHz Bruker Minispectrometer. NMR parameters were compared to quantitative iron levels and tissue histology. Relaxivities R1 and R2 both increased linearly with hepatic iron content, with R2 being more sensitive to iron. CPMG data were well described by a chemical-exchange model and predicted effective iron center dimensions consistent with hemosiderin-filled lysosomes. Nonexponential relaxation was evident at short refocusing intervals with R2 and amplitude behavior suggestive of magnetic susceptibility-based compartmentalization rather than anatomic subdivisions. NMR relaxometry of human liver biopsy specimens yields unique insights into the mechanisms of tissue–iron relaxivity. PMID:16215963

  4. Deeper insight into the reducing biotransformation of bupropion in the human liver.

    PubMed

    Skarydova, Lucie; Tomanova, Radana; Havlikova, Lucie; Stambergova, Hana; Solich, Petr; Wsol, Vladimir

    2014-01-01

    Bupropion is widely used as an antidepressant drug and also as a smoking cessation aid. In humans, this drug is extensively metabolized to form several metabolites. Oxidised hydroxybupropion and two reduced metabolites, threohydrobupropion and erythrohydrobupropion, are major metabolites. All of these metabolites are considered to be active. Although the oxidative metabolic pathway and the central role of CYP2B6 are known, the enzymes that participate in the reduction have not been identified to date. The aim of this study was to confirm the role of human liver subcellular fractions in the metabolism of bupropion and elucidate the contribution of particular carbonyl-reducing enzymes. An HPLC method for the determination of bupropion metabolites was utilised. Bupropion is reduced to threohydrobupropion and less to erythrohydrobupropion in human liver cytosol, microsomes and also mitochondria. Surprisingly, intrinsic clearance for formation of both metabolites is the highest in mitochondrial fraction. Moreover this study provides the first direct evidence that 11β-hydroxysteroid dehydrogenase 1, AKR1C1, AKR1C2, AKR1C3 and CBR1 participate in the reducing biotransformation of bupropion in vitro. The enzyme kinetics of all of these reductases was investigated and kinetic parameters were calculated.

  5. Comparative proteomic analysis on human L-02 liver cells treated with varying concentrations of trichloroethylene.

    PubMed

    Liu, Jianjun; Huang, Haiyan; Xing, Xiumei; Xi, Renrong; Zhuang, Zhixiong; Yuan, Jianhui; Yang, Fan; Zhao, Jin

    2007-03-01

    To determine the differential proteomic expressions in human L-02 liver cells induced by varying concentrations of trichloroethylene (TCE), comparative proteomic analysis was performed on human L-02 liver cells which were treated with varying concentrations of TCE. According to the result of MTT test, we designed four different groups, in which the cells were treated with 0 microM (control group), 3, 10 or 40 microM TCE for 24 h, respectively. Comparative analysis of approximately 800 spots resolved by two-dimensional gel electrophoresis (2DE) in the soluble proteomes of L-02 cells from the four different groups resulted in 10 differential proteins. To identify the differential spots, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) was carried out; if the results from the tool were insufficient, tandem MS (MALDI-TOF-TOF-MS) was then performed. The raw data of peptide mass fingerprints (PMFs) and MS/MS spectra were searched against the IPI human data base for exact matches. Then western blot was employed to verify the result of proteomic analysis, the following result confirmed that the results of proteomic analysis were reliable. These results might provide an insight into the underlying mechanism of TCE intoxication and find biological markers for diagnosis and therapy of TCE-induced diseases.

  6. 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

  7. Aryl hydrocarbon receptor nuclear translocator in human liver is regulated by miR-24

    SciTech Connect

    Oda, Yuki; Nakajima, Miki; Mohri, Takuya; Takamiya, Masataka; Aoki, Yasuhiro; Fukami, Tatsuki; Yokoi, Tsuyoshi

    2012-05-01

    Aryl hydrocarbon receptor nuclear translocator (ARNT) forms a heterodimer with aryl hydrocarbon receptor or hypoxia inducible factor 1α to mediate biological responses to xenobiotic exposure and hypoxia. Although the regulation mechanism of the ARNT expression is largely unknown, earlier studies reported that the human ARNT protein level was decreased by hydrogen peroxide or reactive oxygen species. These stimuli increase the miR-24 level in various human cell lines. In silico analysis predicts that some microRNAs including miR-16 and miR-23b may bind to ARNT mRNA. This background prompted us to investigate whether human ARNT is regulated by microRNAs. Overexpression of miR-24 into HuH-7 and HepG2 cells significantly decreased the ARNT protein level, but not the ARNT mRNA level, indicating translational repression. However, overexpression of miR-16 or miR-23b caused no change in the ARNT expression. The miR-24-dependent down-regulation of ARNT decreased the expression of its downstream genes such as CYP1A1 and carbonic anhydrase IX. Luciferase assay was performed to determine the element on the ARNT mRNA to which miR-24 binds. Finally, it was demonstrated that the miR-24 levels in a panel of 26 human livers were inversely correlated with the protein levels or the translational efficiency of ARNT. Taken together, we found that miR-24 negatively regulates ARNT expression in human liver, affecting the expression of its downstream genes. miR-24 would be one of the factors underlying the mechanisms by which ARNT protein is decreased by reactive oxygen species. -- Highlights: ► Overexpression of miR-24 into human cell lines decreased the ARNT protein level. ► miR-24-dependent down-regulation of ARNT affected the expression of CYP1A1 and CA IX. ► Luciferase assay was performed to identify functional MREs for miR-24 in ARNT mRNA. ► The miR-24 levels inversely correlated with the ARNT protein levels in human liver.

  8. Proteomic profiling in incubation medium of mouse, rat and human precision-cut liver slices for biomarker detection regarding acute drug-induced liver injury.

    PubMed

    van Swelm, Rachel P L; Hadi, Mackenzie; Laarakkers, Coby M M; Masereeuw, Rosalinde; Groothuis, Geny M M; Russel, Frans G M

    2014-09-01

    Drug-induced liver injury is one of the leading causes of drug withdrawal from the market. In this study, we investigated the applicability of protein profiling of the incubation medium of human, mouse and rat precision-cut liver slices (PCLS) exposed to liver injury-inducing drugs for biomarker identification, using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. PCLS were incubated with acetaminophen (APAP), 3-acetamidophenol, diclofenac and lipopolysaccharide for 24-48 h. PCLS medium from all species treated with APAP demonstrated similar changes in protein profiles, as previously found in mouse urine after APAP-induced liver injury, including the same key proteins: superoxide dismutase 1, carbonic anhydrase 3 and calmodulin. Further analysis showed that the concentration of hepcidin, a hepatic iron-regulating hormone peptide, was reduced in PCLS medium after APAP treatment, resembling the decreased mouse plasma concentrations of hepcidin observed after APAP treatment. Interestingly, comparable results were obtained after 3-acetamidophenol incubation in rat and human, but not mouse PCLS. Incubation with diclofenac, but not with lipopolysaccharide, resulted in the same toxicity parameters as observed for APAP, albeit to a lesser extent. In conclusion, proteomics can be applied to identify potential translational biomarkers using the PCLS system.

  9. Activation of mutagens by hepatocytes and liver 9000 X g supernatant from human origin in the Salmonella typhimurium mutagenicity assay. Comparison with rat liver preparations.

    PubMed

    Neis, J M; Yap, S H; van Gemert, P J; Roelofs, H M; Bos, R P; Henderson, P T

    1986-02-01

    The mutagenicity of 10 known genotoxic compounds, of several chemical classes, was measured in Salmonella typhimurium mutagenicity assays comprising isolated human hepatocytes or human liver 9000 X g supernatant (S9) from 4 different individuals, as activating system. The mutagenic activity of several compounds as determined with the Salmonella/hepatocyte suspension assay showed obvious differences when compared with the values obtained in the Salmonella/S9 plate assay. For instance, the mutagenic activity of BZ, DMN and DEN appeared to be much higher in the hepatocyte assay than in the S9 assay. However, 2-AF and 2-AAF were activated more effectively into mutagens in the S9 assay than in the hepatocyte assay. 2-AF was slightly more mutagenic than 2-AAF in the hepatocyte assay, whereas it was far more mutagenic than 2-AAF in the S9 assay. DMN was found more mutagenic than DEN in the hepatocyte assay, whereas in the S9 assay DEN appeared to be slightly more mutagenic. Furthermore, great interindividual differences in the metabolic activation of certain compounds, e.g. BZ and DMN, were observed in the hepatocyte suspension assay, whereas these variations were less evident in the S9 plate assay. Comparison of the mutagenicity data obtained with the human liver preparations, with those obtained with rat liver preparations, showed great interspecies differences in the capacity to activate certain chemicals into mutagens. The use of human liver preparations, in particular isolated human hepatocytes, may be of great value in studies on inter- and intraspecies variations in metabolic activation of genotoxic agents.

  10. Mode-of-action analysis for induction of rat liver tumors by pyrethrins: relevance to human cancer risk.

    PubMed

    Osimitz, Thomas G; Lake, Brian G

    2009-01-01

    High doses of pyrethrins have been shown to produce liver tumors in female rats. Pyrethrins are not genotoxic agents. Pyrethrins produce liver tumors in rats by a mode of action (MOA) involving induction of hepatic xenobiotic metabolising enzymes, hypertrophy, increased cell proliferation, and the development of altered hepatic foci. The relevance of pyrethrins-induced rat liver tumors to human health was assessed by using the 2006 International Programme on Chemical Safety Human Relevance Framework. The postulated rodent tumor MOA was tested against the Bradford Hill criteria and was found to satisfy the conditions of dose and temporal concordance, biological plausibility, coherence, strength, consistency, and specificity that fit with an established mode of action for rodent liver tumor formation by phenobarbital and related compounds, which are activators of the constitutive androstane receptor. Other possible MOAs including mutagenicity, cytotoxicity, hepatic peroxisome proliferation, porphyria, and hormonal pertubation were excluded. The proposed MOA is considered not to be plausible in humans because pyrethrins, like phenobarbital, do not induce cell proliferation in human hepatocytes. Moreover, epidemiological studies with phenobarbital demonstrate that such compounds do not increase the risk of liver tumors in humans. It is concluded that pyrethrins do not pose a hepatocarcinogenic hazard for humans. PMID:19463055

  11. Differential TGFβ pathway targeting by miR-122 in humans and mice affects liver cancer metastasis

    PubMed Central

    Yin, Shenyi; Fan, Yu; Zhang, Hanshuo; Zhao, Zhihua; Hao, Yang; Li, Juan; Sun, Changhong; Yang, Junyu; Yang, Zhenjun; Yang, Xiao; Lu, Jian; Xi, Jianzhong Jeff

    2016-01-01

    Downregulation of a predominantly hepatocyte-specific miR-122 is associated with human liver cancer metastasis, whereas miR-122-deficient mice display normal liver function. Here we show a functional conservation of miR-122 in the TGFβ pathway: miR-122 target site is present in the mouse but not human TGFβR1, whereas a noncanonical target site is present in the TGFβ1 5′UTR in humans and other primates. Experimental switch of the miR-122 target between the receptor TGFβR1 and the ligand TGFβ1 changes the metastatic properties of mouse and human liver cancer cells. High expression of TGFβ1 in human primary liver tumours is associated with poor survival. We identify over 50 other miRNAs orthogonally targeting ligand/receptor pairs in humans and mice, suggesting that these are evolutionarily common events. These results reveal an evolutionary mechanism for miRNA-mediated gene regulation underlying species-specific physiological or pathological phenotype and provide a potentially valuable strategy for treating liver-associated diseases. PMID:26987776

  12. Initial prevalence of anal human papilloma virus infection in liver transplant recipients.

    PubMed

    Grąt, Michał; Grąt, Karolina; Hołówko, Wacław; Malejczyk, Magdalena; Walter de Walthoffen, Szymon; Lewandowski, Zbigniew; Kobryń, Konrad; Patkowski, Waldemar; Majewski, Sławomir; Młynarczyk, Grażyna; Krawczyk, Marek

    2014-08-01

    Although liver transplant recipients are at increased risk of human papilloma virus (HPV)-related anal cancer, limited data are available regarding the initial prevalence of anal HPV infection in this population. Anal swabs collected from 50 liver transplant recipients within the first three postoperative weeks were subjected to real-time polymerase chain reaction for detection of the four HPV genotypes: 6, 11, 16, and 18. Predictors of any, low-risk, and high-risk anal HPV infection were evaluated. Overall, the prevalence of any anal HPV infection was 18.0%, with the corresponding rates for high- and low-risk HPV genotypes being 8.0% and 10.0%, respectively. Infection with any type of anal HPV was higher in patients with hepatitis B virus (HBV) infection (P = 0.027), ≥3 sexual partners (P = 0.031), and alcoholic liver disease (P = 0.063). HBV infection was the only factor significantly associated with high-risk HPV infection (P = 0.038). Male sex (P = 0.050), age ≥52 years (P = 0.016), ≥30 sexual partners (P = 0.003), age at first intercourse ≤18 years (P = 0.045), and time since first intercourse ≥38 years (P = 0.012) were identified as predictors of low-risk HPV infection. These results indicate that HPV vaccination of liver transplant candidates and screening for anal HPV infection in high-risk groups should be considered.

  13. Extracellular matrix signatures of human primary metastatic colon cancers and their metastases to liver

    PubMed Central

    2014-01-01

    Background Colorectal cancer is the third most frequently diagnosed cancer and the third cause of cancer deaths in the United States. Despite the fact that tumor cell-intrinsic mechanisms controlling colorectal carcinogenesis have been identified, novel prognostic and diagnostic tools as well as novel therapeutic strategies are still needed to monitor and target colon cancer progression. We and others have previously shown, using mouse models, that the extracellular matrix (ECM), a major component of the tumor microenvironment, is an important contributor to tumor progression. In order to identify candidate biomarkers, we sought to define ECM signatures of metastatic colorectal cancers and their metastases to the liver. Methods We have used enrichment of extracellular matrix (ECM) from human patient samples and proteomics to define the ECM composition of primary colon carcinomas and their metastases to liver in comparison with normal colon and liver samples. Results We show that robust signatures of ECM proteins characteristic of each tissue, normal and malignant, can be defined using relatively small samples from small numbers of patients. Comparisons with gene expression data from larger cohorts of patients confirm the association of subsets of the proteins identified by proteomic analysis with tumor progression and metastasis. Conclusions The ECM protein signatures of metastatic primary colon carcinomas and metastases to liver defined in this study, offer promise for development of diagnostic and prognostic signatures of metastatic potential of colon tumors. The ECM proteins defined here represent candidate serological or tissue biomarkers and potential targets for imaging of occult metastases and residual or recurrent tumors and conceivably for therapies. Furthermore, the methods described here can be applied to other tumor types and can be used to investigate other questions such as the role of ECM in resistance to therapy. PMID:25037231

  14. Hepatocellular Carcinomas in Cirrhotic and Noncirrhotic Human Livers Share Angiogenic Characteristics

    PubMed Central

    Zeng, Wenjiao; Gouw, Annette S. H.; van den Heuvel, Marius C.; Molema, Grietje; Poppema, Sibrand; van der Jagt, Eric J.

    2010-01-01

    Background The antiangiogenic drug sorafenib has been shown to be an effective treatment for hepatocellular carcinoma (HCC) in patients with liver cirrhosis. It might also be effective in noncirrhotic HCC provided that the angiogenic properties of both tumor types are comparable. The aim of this study is to compare endothelial cell dynamics, microvessel density (MVD), and vessel maturation as indirect markers of angiogenesis in human HCC in cirrhotic and noncirrhotic livers. Materials and Methods In a tertiary care setting, 70 consecutive HCC tumors were analyzed for endothelial cell dynamics. CD34 was applied to identify tumor microvessels, double immunolabeling Ki67/CD34 and activated caspase-3/CD34 to assess endothelial cell proliferation and apoptosis, and α-smooth muscle actin/CD34 for pericyte coverage. These characteristics were compared in cirrhotic (n = 33) and noncirrhotic HCCs (n = 37). Microvessel density was correlated with radiological signs of hypervascularity as obtained with dynamic four-phase CT scans during the arterial and portal phase of contrast enhancement. Results Microvessels in cirrhotic and noncirrhotic HCC were mainly mature. In both groups endothelial cell turnover was low and MVD was not different. There was no correlation between MVD and venous invasion, tumor size, and turnover of tumor cells or endothelial cells. MVD was negatively correlated with contrast washout in the portal venous phase of CT scanning. In transplanted patients, MVD was not correlated with survival, whereas in patients after liver resection a high MVD was associated with a better prognosis. Conclusion Angiogenic characteristics of HCC in cirrhotic and noncirrhotic livers have a remarkable similarity. PMID:20087783

  15. Mass spectrometry-based proteomic analysis of human liver cytochrome(s) P450

    SciTech Connect

    Shrivas, Kamlesh; Mindaye, Samuel T.; Getie-Kebtie, Melkamu; Alterman, Michail A.

    2013-02-15

    The major objective of personalized medicine is to select optimized drug therapies and to a large degree such mission is determined by the expression profiles of cytochrome(s) P450 (CYP). Accordingly, a proteomic case study in personalized medicine is provided by the superfamily of cytochromes P450. Our knowledge about CYP isozyme expression on a protein level is very limited and based exclusively on DNA/mRNA derived data. Such information is not sufficient because transcription and translation events do not lead to correlated levels of expressed proteins. Here we report expression profiles of CYPs in human liver obtained by mass spectrometry (MS)-based proteomic approach. We analyzed 32 samples of human liver microsomes (HLM) of different sexes, ages and ethnicity along with samples of recombinant human CYPs. We have experimentally confirmed that each CYP isozyme can be effectively differentiated by their unique isozyme-specific tryptic peptide(s). Trypsin digestion patterns for almost 30 human CYP isozymes were established. Those findings should assist in selecting tryptic peptides suitable for MS-based quantitation. The data obtained demonstrate remarkable differences in CYP expression profiles. CYP2E1, CYP2C8 and CYP4A11 were the only isozymes found in all HLM samples. Female and pediatric HLM samples revealed much more diverse spectrum of expressed CYPs isozymes compared to male HLM. We have confirmed expression of a number of “rare” CYP (CYP2J2, CYP4B1, CYP4V2, CYP4F3, CYP4F11, CYP8B1, CYP19A1, CYP24A1 and CYP27A1) and obtained first direct experimental data showing expression of such CYPs as CYP2F1, CYP2S1, CYP2W1, CYP4A22, CYP4X1, and CYP26A1 on a protein level. - Highlights: ► First detailed proteomic analysis of CYP isozymes expression in human liver ► Trypsin digestion patterns for almost 30 human CYP isozymes established ► The data obtained demonstrate remarkable differences in CYP expression profiles. ► Female HLM samples revealed more

  16. Kinetics of tris (1-chloro-2-propyl) phosphate (TCIPP) metabolism in human liver microsomes and serum.

    PubMed

    Van den Eede, Nele; Tomy, Gregg; Tao, Fang; Halldorson, Thor; Harrad, Stuart; Neels, Hugo; Covaci, Adrian

    2016-02-01

    Tris(1-chloro-2-propyl) phosphate (TCIPP) is an emerging contaminant which is ubiquitous in the indoor and outdoor environment. Moreover, its presence in human body fluids and biota has been evidenced. Since no quantitative data exist on the biotransformation or stability of TCIPP in the human body, we performed an in vitro incubation of TCIPP with human liver microsomes (HLM) and human serum (HS). Two metabolites, namely bis(2-chloro-isopropyl) phosphate (BCIPP) and bis(1-chloro-2-propyl) 1-hydroxy-2-propyl phosphate (BCIPHIPP), were quantified in a kinetic study using HLM or HS (only BCIPP, the hydrolysis product) and LC-MS. The Michaelis-Menten model fitted best the NADPH-dependent formation of BCIPHIPP and BCIPP in HLM, with respective V(MAX) of 154 ± 4 and 1470 ± 110 pmol/min/mg protein and respective apparent K(m) of 80.2 ± 4.4 and 96.1 ± 14.5 μM. Hydrolases, which are naturally present in HLM, were also involved in the production of BCIPP. A HS paraoxonase assay could not detect any BCIPP formation above 38.6 ± 10.8 pmol/min/μL serum. Our data indicate that BCIPP is the major metabolite of TCIPP formed in the liver. To our knowledge, this is the first quantitative assessment of the stability of TCIPP in tissues of humans or any other species. Further research is needed to confirm whether these biotransformation reactions are associated with a decrease or increase in toxicity. PMID:26473552

  17. Human plasma concentrations of herbicidal carbamate molinate extrapolated from the pharmacokinetics established in in vivo experiments with chimeric mice with humanized liver and physiologically based pharmacokinetic modeling.

    PubMed

    Yamashita, Masanao; Suemizu, Hiroshi; Murayama, Norie; Nishiyama, Sayako; Shimizu, Makiko; Yamazaki, Hiroshi

    2014-10-01

    To predict concentrations in humans of the herbicidal carbamate molinate, used exclusively in rice cultivation, a forward dosimetry approach was carried out using data from lowest-observed-adverse-effect-level doses orally administered to rats, wild type mice, and chimeric mice with humanized liver and from in vitro human and rodent experiments. Human liver microsomes preferentially mediated hydroxylation of molinate, but rat livers additionally produced molinate sulfoxide and an unidentified metabolite. Adjusted animal biomonitoring equivalents for molinate and its primary sulfoxide from animal studies were scaled to human biomonitoring equivalents using known species allometric scaling factors and human metabolic data with a simple physiologically based pharmacokinetic (PBPK) model. The slower disposition of molinate and accumulation of molinate sulfoxide in humans were estimated by modeling after single and multiple doses compared with elimination in rodents. The results from simplified PBPK modeling in combination with chimeric mice with humanized liver suggest that ratios of estimated parameters of molinate sulfoxide exposure in humans to those in rats were three times as many as general safety factor of 10 for species difference in toxicokinetics. Thus, careful regulatory decision is needed when evaluating the human risk resulting from exposure to low doses of molinate and related carbamates based on data obtained from rats. PMID:25016177

  18. Human plasma concentrations of herbicidal carbamate molinate extrapolated from the pharmacokinetics established in in vivo experiments with chimeric mice with humanized liver and physiologically based pharmacokinetic modeling.

    PubMed

    Yamashita, Masanao; Suemizu, Hiroshi; Murayama, Norie; Nishiyama, Sayako; Shimizu, Makiko; Yamazaki, Hiroshi

    2014-10-01

    To predict concentrations in humans of the herbicidal carbamate molinate, used exclusively in rice cultivation, a forward dosimetry approach was carried out using data from lowest-observed-adverse-effect-level doses orally administered to rats, wild type mice, and chimeric mice with humanized liver and from in vitro human and rodent experiments. Human liver microsomes preferentially mediated hydroxylation of molinate, but rat livers additionally produced molinate sulfoxide and an unidentified metabolite. Adjusted animal biomonitoring equivalents for molinate and its primary sulfoxide from animal studies were scaled to human biomonitoring equivalents using known species allometric scaling factors and human metabolic data with a simple physiologically based pharmacokinetic (PBPK) model. The slower disposition of molinate and accumulation of molinate sulfoxide in humans were estimated by modeling after single and multiple doses compared with elimination in rodents. The results from simplified PBPK modeling in combination with chimeric mice with humanized liver suggest that ratios of estimated parameters of molinate sulfoxide exposure in humans to those in rats were three times as many as general safety factor of 10 for species difference in toxicokinetics. Thus, careful regulatory decision is needed when evaluating the human risk resulting from exposure to low doses of molinate and related carbamates based on data obtained from rats.

  19. Liver transplantation☆

    PubMed Central

    Rossi, M.; Mennini, G.; Lai, Q.; Ginanni Corradini, S.; Drudi, F.M.; Pugliese, F.; Berloco, P.B.

    2007-01-01

    Orthotopic liver transplantation (OLT) involves the substitution of a diseased native liver with a normal liver (or part of one) taken from a deceased or living donor. Considered an experimental procedure through the 1980s, OLT is now regarded as the treatment of choice for a number of otherwise irreversible forms of acute and chronic liver disease. The first human liver transplantation was performed in the United States in 1963 by Prof. T.E. Starzl of the University of Colorado. The first OLT to be performed in Italy was done in 1982 by Prof. R. Cortesini. The procedure was successfully performed at the Policlinico Umberto I of the University of Rome (La Sapienza). The paper reports the indications for liver transplantation, donor selection and organ allocation in our experience, surgical technique, immunosuppression, complications and results of liver transplantation in our center. PMID:23396075

  20. Riboflavin uptake by the human-derived liver cells Hep G2: mechanism and regulation.

    PubMed

    Said, H M; Ortiz, A; Ma, T Y; McCloud, E

    1998-09-01

    The water-soluble vitamin riboflavin (RF) plays a critical role in many metabolic reactions, and thus, is essential for normal cellular functions and growth. The liver plays a central role in normal RF metabolism and is the site of maximal utilization of the vitamin. The mechanism of liver uptake of RF has been studied in animals, but no information is available describing the mechanism of the vitamin uptake in the human situation and its cellular regulation. In this study, we used the human-derived liver cells Hep G2 as an in vitro model system to address these issues. Uptake of RF by Hep G2 cells was found to be temperature- and energy-dependent but Na+-independent in nature. Uptake seemed to involve a carrier-mediated process as indicated by the saturation as a function of substrate concentration (apparent Km 0.41 +/- 0.08 microM), and by the ability of the structural analogs lumiflavin and lumichrome to inhibit the uptake process [inhibition constant (K) of 1.84 and 6.32 microM, respectively]. RF uptake was energy dependent, and was inhibited by the -SH group blocker p-chloromercuriphenylsulfonate (p-CMPS) (Ki of 0.10 mM). Specific modulators of intracellular protein kinase A (PKA)-, protein kinase C (PKC)-, and protein tyrosine kinase (PTK)-mediated pathways did not affect RF uptake by Hep G2 cells. On the other hand, specific inhibitors of Ca2+/calmodulin-mediated pathway significantly inhibited the uptake process; this effect seemed to be mediated through a decrease in the Vmax of the substrate uptake process. Maintaining Hep G2 cells in a RF-deficient growth medium was associated with a significant up-regulation in the substrate uptake; this effect was specific for RF and was mediated mainly by means of an increase in the Vmax of the uptake process. These results describe, for the first time, the mechanism and cellular regulation of RF uptake by a human-derived liver cellular preparation, and shows the involvement of a carrier-mediated system in the uptake

  1. A human liver microphysiology platform for investigating physiology, drug safety, and disease models

    PubMed Central

    Vernetti, Lawrence A.; Senutovitch, Nina; Boltz, Robert; DeBiasio, Richard; Shun, Tong Ying; Gough, Albert; Taylor, D. Lansing

    2015-01-01

    This paper describes the development and characterization of a microphysiology platform for drug safety and efficacy in liver models of disease that includes a human, 3D, microfluidic, four-cell, sequentially layered, self-assembly liver model (SQL-SAL); fluorescent protein biosensors for mechanistic readouts; as well as a microphysiology system database (MPS-Db) to manage, analyze, and model data. The goal of our approach is to create the simplest design in terms of cells, matrix materials, and microfluidic device parameters that will support a physiologically relevant liver model that is robust and reproducible for at least 28 days for stand-alone liver studies and microfluidic integration with other organs-on-chips. The current SQL-SAL uses primary human hepatocytes along with human endothelial (EA.hy926), immune (U937) and stellate (LX-2) cells in physiological ratios and is viable for at least 28 days under continuous flow. Approximately, 20% of primary hepatocytes and/or stellate cells contain fluorescent protein biosensors (called sentinel cells) to measure apoptosis, reactive oxygen species (ROS) and/or cell location by high content analysis (HCA). In addition, drugs, drug metabolites, albumin, urea and lactate dehydrogenase (LDH) are monitored in the efflux media. Exposure to 180μM troglitazone or 210μM nimesulide produced acute toxicity within 2–4 days, whereas 28μM troglitazone produced a gradual and much delayed toxic response over 21 days, concordant with known mechanisms of toxicity, while 600μM caffeine had no effect. Immune-mediated toxicity was demonstrated with trovafloxacin with lipopolysaccharide (LPS), but not levofloxacin with LPS. The SQL-SAL exhibited early fibrotic activation in response to 30nM methotrexate, indicated by increased stellate cell migration, expression of alpha-smooth muscle actin and collagen, type 1, alpha 2. Data collected from the in vitro model can be integrated into a database with access to related chemical

  2. A human liver microphysiology platform for investigating physiology, drug safety, and disease models.

    PubMed

    Vernetti, Lawrence A; Senutovitch, Nina; Boltz, Robert; DeBiasio, Richard; Shun, Tong Ying; Gough, Albert; Taylor, D Lansing

    2016-01-01

    This paper describes the development and characterization of a microphysiology platform for drug safety and efficacy in liver models of disease that includes a human, 3D, microfluidic, four-cell, sequentially layered, self-assembly liver model (SQL-SAL); fluorescent protein biosensors for mechanistic readouts; as well as a microphysiology system database (MPS-Db) to manage, analyze, and model data. The goal of our approach is to create the simplest design in terms of cells, matrix materials, and microfluidic device parameters that will support a physiologically relevant liver model that is robust and reproducible for at least 28 days for stand-alone liver studies and microfluidic integration with other organs-on-chips. The current SQL-SAL uses primary human hepatocytes along with human endothelial (EA.hy926), immune (U937) and stellate (LX-2) cells in physiological ratios and is viable for at least 28 days under continuous flow. Approximately, 20% of primary hepatocytes and/or stellate cells contain fluorescent protein biosensors (called sentinel cells) to measure apoptosis, reactive oxygen species (ROS) and/or cell location by high content analysis (HCA). In addition, drugs, drug metabolites, albumin, urea and lactate dehydrogenase (LDH) are monitored in the efflux media. Exposure to 180 μM troglitazone or 210 μM nimesulide produced acute toxicity within 2-4 days, whereas 28 μM troglitazone produced a gradual and much delayed toxic response over 21 days, concordant with known mechanisms of toxicity, while 600 µM caffeine had no effect. Immune-mediated toxicity was demonstrated with trovafloxacin with lipopolysaccharide (LPS), but not levofloxacin with LPS. The SQL-SAL exhibited early fibrotic activation in response to 30 nM methotrexate, indicated by increased stellate cell migration, expression of alpha-smooth muscle actin and collagen, type 1, alpha 2. Data collected from the in vitro model can be integrated into a database with access to related

  3. A human liver microphysiology platform for investigating physiology, drug safety, and disease models.

    PubMed

    Vernetti, Lawrence A; Senutovitch, Nina; Boltz, Robert; DeBiasio, Richard; Shun, Tong Ying; Gough, Albert; Taylor, D Lansing

    2016-01-01

    This paper describes the development and characterization of a microphysiology platform for drug safety and efficacy in liver models of disease that includes a human, 3D, microfluidic, four-cell, sequentially layered, self-assembly liver model (SQL-SAL); fluorescent protein biosensors for mechanistic readouts; as well as a microphysiology system database (MPS-Db) to manage, analyze, and model data. The goal of our approach is to create the simplest design in terms of cells, matrix materials, and microfluidic device parameters that will support a physiologically relevant liver model that is robust and reproducible for at least 28 days for stand-alone liver studies and microfluidic integration with other organs-on-chips. The current SQL-SAL uses primary human hepatocytes along with human endothelial (EA.hy926), immune (U937) and stellate (LX-2) cells in physiological ratios and is viable for at least 28 days under continuous flow. Approximately, 20% of primary hepatocytes and/or stellate cells contain fluorescent protein biosensors (called sentinel cells) to measure apoptosis, reactive oxygen species (ROS) and/or cell location by high content analysis (HCA). In addition, drugs, drug metabolites, albumin, urea and lactate dehydrogenase (LDH) are monitored in the efflux media. Exposure to 180 μM troglitazone or 210 μM nimesulide produced acute toxicity within 2-4 days, whereas 28 μM troglitazone produced a gradual and much delayed toxic response over 21 days, concordant with known mechanisms of toxicity, while 600 µM caffeine had no effect. Immune-mediated toxicity was demonstrated with trovafloxacin with lipopolysaccharide (LPS), but not levofloxacin with LPS. The SQL-SAL exhibited early fibrotic activation in response to 30 nM methotrexate, indicated by increased stellate cell migration, expression of alpha-smooth muscle actin and collagen, type 1, alpha 2. Data collected from the in vitro model can be integrated into a database with access to related

  4. Metabolite profiling and pharmacokinetic evaluation of hydrocortisone in a perfused three-dimensional human liver bioreactor.

    PubMed

    Sarkar, Ujjal; Rivera-Burgos, Dinelia; Large, Emma M; Hughes, David J; Ravindra, Kodihalli C; Dyer, Rachel L; Ebrahimkhani, Mohammad R; Wishnok, John S; Griffith, Linda G; Tannenbaum, Steven R

    2015-07-01

    Endotoxin lipopolysaccharide (LPS) is known to cause liver injury primarily involving inflammatory cells such as Kupffer cells, but few in vitro culture models are applicable for investigation of inflammatory effects on drug metabolism. We have developed a three-dimensional human microphysiological hepatocyte-Kupffer cell coculture system and evaluated the anti-inflammatory effect of glucocorticoids on liver cultures. LPS was introduced to the cultures to elicit an inflammatory response and was assessed by the release of proinflammatory cytokines, interleukin 6 and tumor necrosis factor α. A sensitive and specific reversed-phase-ultra high-performance liquid chromatography-quadrupole time of flight-mass spectrometry method was used to evaluate hydrocortisone disappearance and metabolism at near physiologic levels. For this, the systems were dosed with 100 nM hydrocortisone and circulated for 2 days; hydrocortisone was depleted to approximately 30 nM, with first-order kinetics. Phase I metabolites, including tetrahydrocortisone and dihydrocortisol, accounted for 8-10% of the loss, and 45-52% consisted of phase II metabolites, including glucuronides of tetrahydrocortisol and tetrahydrocortisone. Pharmacokinetic parameters, i.e., half-life, rate of elimination, clearance, and area under the curve, were 23.03 hours, 0.03 hour(-1), 6.6 × 10(-5) l⋅hour(-1), and 1.03 (mg/l)*h, respectively. The ability of the bioreactor to predict the in vivo clearance of hydrocortisone was characterized, and the obtained intrinsic clearance values correlated with human data. This system offers a physiologically relevant tool for investigating hepatic function in an inflamed liver. PMID:25926431

  5. Progressive graft fibrosis and donor-specific human leukocyte antigen antibodies in pediatric late liver allografts.

    PubMed

    Miyagawa-Hayashino, Aya; Yoshizawa, Atushi; Uchida, Yoichiro; Egawa, Hiroto; Yurugi, Kimiko; Masuda, Satohiro; Minamiguchi, Sachiko; Maekawa, Taira; Uemoto, Shinji; Haga, Hironori

    2012-11-01

    The role of donor-specific anti-human leukocyte antigen antibodies (DSAs) that develop late after living donor liver transplantation is unknown. Seventy-nine pediatric recipients who had good graft function and underwent protocol liver biopsy more than 5 years after transplantation (median = 11 years, range = 5-20 years) were reviewed. DSAs were determined with the Luminex single-antigen bead assay at the time of the last biopsy, and complement component 4d (C4d) immunostaining was assessed at the times of the last biopsy and the previous biopsy. The donor specificity of antibodies could be identified in 67 patients: DSAs were detected in 32 patients (48%), and they were usually against human leukocyte antigen class II (30 cases) but were rarely against class I (2 cases). These patients had a higher frequency of bridging fibrosis or cirrhosis (28/32 or 88%) than DSA-negative patients (6/35 or 17%, P < 0.001). Fibrosis was likely to be centrilobular-based. DSA-positive patients, in comparison with DSA-negative patients, had higher frequencies of diffuse/focal endothelial C4d staining (P < 0.001) and mild/indeterminate acute rejection [15/32 (47%) versus 5/35 (14%), P = 0.004]. Four DSA-negative patients were off immunosuppression, whereas no patients in the DSA-positive group were (P = 0.048). In conclusion, the high prevalence of graft fibrosis and anti-class II DSAs in late protocol biopsy samples suggests that humoral alloreactivity may contribute to the process of unexplained graft fibrosis late after liver transplantation.

  6. Comprehensive mapping of protein N-glycosylation in human liver by combining hydrophilic interaction chromatography and hydrazide chemistry.

    PubMed

    Zhu, Jun; Sun, Zhen; Cheng, Kai; Chen, Rui; Ye, Mingliang; Xu, Bo; Sun, Deguang; Wang, Liming; Liu, Jing; Wang, Fangjun; Zou, Hanfa

    2014-03-01

    Although glycoproteomics is greatly developed in recent years, our knowledge about N-glycoproteome of human tissues is still very limited. In this study, we comprehensively mapped the N-glycosylation sites of human liver by combining click maltose-hydrophilic interaction chromatography (HILIC) and the improved hydrazide chemistry. The specificity could be as high as 90% for hydrazide chemistry and 80% for HILIC. Altogether, we identified 14,480 N-glycopeptides matched with N-!P-[S|T|C] sequence motif from human liver, corresponding to 2210 N-glycoproteins and 4783 N-glycosylation sites. These N-glycoproteins are widely involved into different types of biological processes, such as hepatic stellate cell activation and acute phase response of human liver, which all highly associate with the progression of liver diseases. Moreover, the exact N-glycosylation sites of some key-regulating proteins within different human liver physiological processes were also obtained, such as E-cadherin, transforming growth factor beta receptor and 29 members of G protein coupled receptors family.

  7. Genetics of the mammalian phenylalanine hydroxylase system. Studies of human liver phenylalanine hydroxylase subunit structure and of mutations in phenylketonuria.

    PubMed Central

    Choo, K H; Cotton, R G; Danks, D M; Jennings, I G

    1979-01-01

    Phenylalanine hydroxylase was purified from crude extracts of human livers which show enzyme activity by usine two different methods: (a) affinity chromatography and (b) immunoprecipitation with an antiserum against highly purified monkey liver phenylalanine hydroxylase. Purified human liver phenylalanine hydroxylase has an estimated mol. wt. of 275 000, and subunit mol. wts. of approx. 50 000 and 49 000. These two molecular-weight forms are designated H and L subunits. On two-dimensional polyacrylamide gel under dissociating conditions, enzyme purified by the two methods revealed at least six subunit species, which were resolved into two size classes. Two of these species have a molecular weight corresponding to that of the H subunit, whereas the other four have a molecular weight corresponding to that of the L subunit. This evidence indicates that active phenylalanine hydroxylase purified from human liver is composed of a mixture of sununits which are different in charge and size. None of the subunit species could be detected in crude extracts of livers from two patients with classical phenylketonuria by either the affinity or the immunoprecipitation method. However, they were present in liver from a patient with malignant hyperphenylalaninaemia with normal activity of dihydropteridine reductase. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:496890

  8. Transesterification of a series of 12 parabens by liver and small-intestinal microsomes of rats and humans.

    PubMed

    Fujino, Chieri; Watanabe, Yoko; Uramaru, Naoto; Kitamura, Shigeyuki

    2014-02-01

    Hydrolytic transformation of parabens (4-hydroxybenzoic acid esters; used as antibacterial agents) to 4-hydroxybenzoic acid and alcohols by tissue microsomes is well-known both in vitro and in vivo. Here, we investigated transesterification reactions of parabens catalyzed by rat and human microsomes, using a series of 12 parabens with C1-C12 alcohol side chains. Transesterification of parabens by rat liver and small-intestinal microsomes occurred in the presence of alcohols in the microsomal incubation mixture. Among the 12 parabens, propylparaben was most effectively transesterified by rat liver microsomes with methanol or ethanol, followed by butylparaben. Relatively low activity was observed with longer-side-chain parabens. In contrast, small-intestinal microsomes exhibited higher activity towards moderately long side-chain parabens, and showed the highest activity toward octylparaben. When parabens were incubated with liver or small-intestinal microsomes in the presence of C1-C12 alcohols, ethanol and decanol were most effectively transferred to parabens by rat liver microsomes and small-intestinal microsomes, respectively. Human liver and small-intestinal microsomes also exhibited significant transesterification activities with different substrate specificities, like rat microsomes. Carboxylesterase isoforms, CES1b and CES1c, and CES2, exhibited significant transesterification activity toward parabens, and showed similar substrate specificity to human liver and small-intestinal microsomes, respectively.

  9. Comparative studies of different cryopreservation methods for mesenchymal stem cells derived from human fetal liver.

    PubMed

    Todorov, Plamen; Hristova, Elena; Konakchieva, Rossitza; Michova, Antoaneta; Dimitrov, Josif

    2010-03-29

    Fetal stem cells possess some intriguing characteristics, which delineate them as promising cellular therapeutics. They are less immunogenic, at lower stage of differentiation and have higher potential for repopulation and migration. Furthermore, the fetal stem cells secrete a set of cytokines and growth factors, which stimulate the regeneration of the recipient tissue. The present study indicated that the adhesive fraction of human fetal liver cells possessed the morphological characteristics of mesenchymal stem cells, as well as potential to differentiate into adipocyte and osteoblast lineages. The immunophenotypic analysis showed that the cells expressed CD13, CD73, CD90 and CD105 (typical for mesenchymal stem cells) and lacked the haematopoietic lineage markers CD34 and CD45. Addressing the issue of the low-temperature storage of the human fetal liver cells, four different methods for cryopreservation were assessed: conventional slow freezing, program freezing and two vitrification protocols. The obtained results demonstrated that the cells were cryotolerant and maintained their properties and differentiation potential after thawing. Program freezing showed to be the most efficient method for cryopreservation of the investigated cells.

  10. The furano norclerodane diterpenoid disobulbin-D induces apoptosis in normal human liver L-02 cells.

    PubMed

    Ma, Min; Jiang, Zhenzhou; Ruan, Jinlan; Tan, Xinqi; Liu, Jin; Wang, Cuifen; Zha, Xiao Ming; Zhang, Luyong

    2012-09-01

    Disobulbin-D (DBD), a hepatotoxic furano norclerodane diterpenoid, was isolated by bio-guided fractionation from the rhizome of Dioscorea bulbifera L. In working toward elucidating the cellular and molecular mechanisms of DBD toxicity, we treated normal human liver cell line L-02 cells with DBD in vitro and evaluated its toxicity in terms of cell viability, morphologic changes, induction of apoptosis/necrosis, and caspase 3 activity. The viability of L-02 cells was inhibited by DBD in a concentration and time-dependent manner. Apoptosis was supported by the Annexin V and propidium iodide assay, Hoechst 33258 staining, and the occurrence of a sub-G(1) peak. DBD can cause an increase in caspase 3 activity, and pretreatment with Ac-DEVD-CHO blocked cell death and attenuated the apoptosis, showing that DBD-induced L-02 cell apoptosis is caspase 3-dependent. These results suggest that the effects of DBD on the growth of normal human liver L-02 cells may be due to its induction of cell apoptosis, which may also explain the toxicity observed in the plants containing furano clerodane diterpenoids. PMID:21211949

  11. Reversal of diabetes following transplantation of an insulin-secreting human liver cell line: Melligen cells.

    PubMed

    Lawandi, Janet; Tao, Chang; Ren, Binhai; Williams, Paul; Ling, Dora; Swan, M Anne; Nassif, Najah T; Torpy, Fraser R; O'Brien, Bronwyn A; Simpson, Ann M

    2015-01-01

    As an alternative to the transplantation of islets, a human liver cell line has been genetically engineered to reverse type 1 diabetes (TID). The initial liver cell line (Huh7ins) commenced secretion of insulin in response to a glucose concentration of 2.5 mmol/l. After transfection of the Huh7ins cells with human islet glucokinase, the resultant Melligen cells secreted insulin in response to glucose within the physiological range; commencing at 4.25 mmol/l. Melligen cells exhibited increased glucokinase enzymatic activity in response to physiological glucose concentrations, as compared with Huh7ins cells. When transplanted into diabetic immunoincompetent mice, Melligen cells restored normoglycemia. Quantitative real-time polymerase chain reaction (qRT-PCR) revealed that both cell lines expressed a range of β-cell transcription factors and pancreatic hormones. Exposure of Melligen and Huh7ins cells to proinflammatory cytokines (TNF-α, IL-1β, and IFN-γ) affected neither their viability nor their ability to secrete insulin to glucose. Gene expression (microarray and qRT-PCR) analyses indicated the survival of Melligen cells in the presence of known β-cell cytotoxins was associated with the expression of NF-κB and antiapoptotic genes (such as BIRC3). This study describes the successful generation of an artificial β-cell line, which, if encapsulated to avoid allograft rejection, may offer a clinically applicable cure for T1D. PMID:26029722

  12. Branched chain amino acid metabolism profiles in progressive human nonalcoholic fatty liver disease.

    PubMed

    Lake, April D; Novak, Petr; Shipkova, Petia; Aranibar, Nelly; Robertson, Donald G; Reily, Michael D; Lehman-McKeeman, Lois D; Vaillancourt, Richard R; Cherrington, Nathan J

    2015-03-01

    Nonalcoholic fatty liver disease (NAFLD) is a globally widespread disease of increasing clinical significance. The pathological progression of the disease from simple steatosis to nonalcoholic steatohepatitis (NASH) has been well defined, however, the contribution of altered branched chain amino acid metabolomic profiles to the progression of NAFLD is not known. The three BCAAs: leucine, isoleucine and valine are known to mediate activation of several important hepatic metabolic signaling pathways ranging from insulin signaling to glucose regulation. The purpose of this study is to profile changes in hepatic BCAA metabolite levels with transcriptomic changes in the progression of human NAFLD to discover novel mechanisms of disease progression. Metabolomic and transcriptomic data sets representing the spectrum of human NAFLD (normal, steatosis, NASH fatty, and NASH not fatty livers) were utilized for this study. During the transition from steatosis to NASH, increases in the levels of leucine (127% of normal), isoleucine (139%), and valine (147%) were observed. Carnitine metabolites also exhibited significantly elevated profiles in NASH fatty and NASH not fatty samples and included propionyl, hexanoyl, lauryl, acetyl and butyryl carnitine. Amino acid and BCAA metabolism gene sets were significantly enriched among downregulated genes during NASH. These cumulative alterations in BCAA metabolite and amino acid metabolism gene profiles represent adaptive physiological responses to disease-induced hepatic stress in NASH patients.

  13. Cytotoxicity of macrolide antibiotics in a cultured human liver cell line.

    PubMed

    Viluksela, M; Vainio, P J; Tuominen, R K

    1996-09-01

    Cytotoxicity of erythromycin base, erythromycin estolate, erythromycin-11,12-cyclic carbonate, roxithromycin, clarithromycin and azithromycin was compared in cultured human non-malignant Chang liver cells using reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and cellular protein concentration as end points of toxicity. Erythromycin estolate was the most toxic macrolide in all tests differing clearly from all the other macrolides studied. Erythromycin-11,12-cyclic carbonate was also more toxic than the other macrolides. Roxithromycin and clarithromycin were the next toxic derivatives, while erythromycin base and azithromycin were least toxic. Thus, cytotoxicity of the new semisynthetic macrolides, roxithromycin, clarithromycin and azithromycin, is not substantially different from that of erythromycin base. In view of the low level of hepatotoxicity of macrolides hitherto reported in humans, the results do not suggest any substantial risk for hepatic disorders related to the use of azithromycin, clarithromycin and roxithromycin.

  14. Hepatitis E Virus (HEV) Genotype 3 Infection of Human Liver Chimeric Mice as a Model for Chronic HEV Infection

    PubMed Central

    Pas, Suzan D.; van der Net, Guido; de Man, Robert A.; Osterhaus, Albert D. M. E.; Haagmans, Bart L.; Boonstra, Andre

    2016-01-01

    ABSTRACT Genotype 3 (gt3) hepatitis E virus (HEV) infections are emerging in Western countries. Immunosuppressed patients are at risk of chronic HEV infection and progressive liver damage, but no adequate model system currently mimics this disease course. Here we explore the possibilities of in vivo HEV studies in a human liver chimeric mouse model (uPA+/+Nod-SCID-IL2Rγ−/−) next to the A549 cell culture system, using HEV RNA-positive EDTA-plasma, feces, or liver biopsy specimens from 8 immunocompromised patients with chronic gt3 HEV. HEV from feces- or liver-derived inocula showed clear virus propagation within 2 weeks after inoculation onto A549 cells, compared to slow or no HEV propagation of HEV RNA-positive, EDTA-plasma samples. These in vitro HEV infectivity differences were mirrored in human-liver chimeric mice after intravenous (i.v.) inoculation of selected samples. HEV RNA levels of up to 8 log IU HEV RNA/gram were consistently present in 100% of chimeric mouse livers from week 2 to week 14 after inoculation with human feces- or liver-derived HEV. Feces and bile of infected mice contained moderate to large amounts of HEV RNA, while HEV viremia was low and inconsistently detected. Mouse-passaged HEV could subsequently be propagated for up to 100 days in vitro. In contrast, cell culture-derived or seronegative EDTA-plasma-derived HEV was not infectious in inoculated animals. In conclusion, the infectivity of feces-derived human HEV is higher than that of EDTA-plasma-derived HEV both in vitro and in vivo. Persistent HEV gt3 infections in chimeric mice show preferential viral shedding toward mouse bile and feces, paralleling the course of infection in humans. IMPORTANCE Hepatitis E virus (HEV) genotype 3 infections are emerging in Western countries and are of great concern for immunosuppressed patients at risk for developing chronic HEV infection. Lack of adequate model systems for chronic HEV infection hampers studies on HEV infectivity and transmission

  15. Human liver finite element model validation using compressive and tensile experimental data - biomed 2013.

    PubMed

    Davis, Matthew L; Moreno, Daniel P; Vavalle, Nicholas A; Gayzik, F Scott

    2013-01-01

    Motor vehicle crashes commonly result in blunt abdominal trauma. Approximately 19,000 such injuries occur each year in the United States. While finite element models of the human body are becoming an important tool for injury assessment, their reliability depends on the accuracy of the material models used. Recently, Samur et al. proposed a hyperelastic and viscoelastic material model of the liver. The aim of this study was to compare the results of a computational model using this material law to uniaxial tension and compression data from biomechanical tests on liver samples by Kemper et al. In this study, the liver samples were modeled using the finite element method. Both the tension and compression test specimen geometries were created from descriptions in the literature. Each sample was meshed using four approaches: fine hexahedral, coarse hexahedral, fine tetrahedral, and coarse tetrahedral. The average element edge lengths of the coarse and fine meshes were 5 mm and 2.5 mm respectively. The samples were loaded in both tension and compression at four rates: 0.01 strain/sec, 0.1 strain/sec, 1 strain/sec, and 10 strain/sec. For each mesh type (n=4), strain rate (n=4), and loading condition (n=2), 32 simulations in total, the results were plotted against the published experimental data. The results were quantitatively evaluated for magnitude and phase agreement with the experimental data using an objective comparison software package, CORA. The model predicted the tensile response of the liver sample more accurately than the compressive response with an average CORA size error factor of 0.66 versus 0.19 for the compressive model (1 is a perfect match). The fine tetrahedral, fine hexahedral, and coarse hexahedral meshes predicted a similar response. The worst performing mesh was the coarse tetrahedral mesh, which had an average size error factor of 8.6% higher than the fine tetrahedral simulations. The peak stress in both tension and compression varied as a

  16. In vitro assessment of drug-induced liver steatosis based on human dermal stem cell-derived hepatic cells.

    PubMed

    Rodrigues, Robim M; Branson, Steven; De Boe, Veerle; Sachinidis, Agapios; Rogiers, Vera; De Kock, Joery; Vanhaecke, Tamara

    2016-03-01

    Steatosis, also known as fatty liver disease (FLD), is a disorder in which the lipid metabolism of the liver is disturbed, leading to the abnormal retention of lipids in hepatocytes. FLD can be induced by several drugs, and although it is mostly asymptomatic, it can lead to steatohepatitis, which is associated with liver inflammation and damage. Drug-induced liver injury is currently the major cause of postmarketing withdrawal of pharmaceuticals and discontinuation of the development of new chemical entities. Therefore, the potential induction of steatosis must be evaluated during preclinical drug development. However, robust human-relevant in vitro models are lacking. In the present study, we explore the applicability of hepatic cells (hSKP-HPCs) derived from postnatal skin precursors, a stem cell population residing in human dermis, to investigate the steatosis-inducing effects of sodium valproate (Na-VPA). Exposure of hSKP-HPC to sub-cytotoxic concentrations of this reference steatogenic compound showed an increased intracellular accumulation of lipid droplets, and the modulation of key factors involved in lipid metabolism. Using a toxicogenomics approach, we further compared Na-VPA-treated hSKP-HPC and Na-VPA-treated primary human hepatocytes to liver samples from patients suffering from mild and advanced steatosis. Our data show that in hSKP-HPC exposed to Na-VPA and liver samples of patients suffering from mild steatosis, but not in primary human hepatocytes, "liver steatosis" was efficiently identified as a toxicological response. These findings illustrate the potential of hSKP-HPC as a human-relevant in vitro model to identify hepatosteatotic effects of chemical compounds.

  17. Intermedilysin, a novel cytotoxin specific for human cells secreted by Streptococcus intermedius UNS46 isolated from a human liver abscess.

    PubMed Central

    Nagamune, H; Ohnishi, C; Katsuura, A; Fushitani, K; Whiley, R A; Tsuji, A; Matsuda, Y

    1996-01-01

    A novel cytotoxin (intermedilysin) specific for human cells was identified as a cytolytic factor of Streptococcus intermedius UNS46 isolated from a human liver abscess. Intermedilysin caused human cell death with membrane blebs. Intermedilysin was purified from UNS46 culture medium by means of gel filtration and hydrophobic chromatography. The purified toxin was resolved into major and minor bands of 54 and 53 kDa, respectively, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These proteins reacted with an antibody against intermedilysin. Five internal peptide fragments of intermedilysin were sequenced and found to have 42 to 71% homology with the thiol-activated cytotoxin pneumolysin. However, the action of intermedilysin differed from that of thiol-activated cytotoxins, especially in terms of a lack of activation by dithiothreitol and resistance to treatments with N-ethylmaleimide and 5,5'-dithio-bis-(2-nitrobenzoic acid), although cholesterol inhibited the toxin activity. Intermedilysin was potently hemolytic on human erythrocytes but was 100-fold less effective on chimpanzee and cynomolgus monkey erythrocytes. Intermedilysin was not hemolytic in nine other animal species tested. Since human erythrocytes treated with trypsin were far less sensitive to intermedilysin than were the intact cells, a cell membrane protein(s) may participate in the intermedilysin action. These data demonstrated that intermedilysin is distinguishable from all known bacterial cytolysins. PMID:8757839

  18. Expression and localization of augmenter of liver regeneration in human muscle tissue.

    PubMed

    Polimeno, Lorenzo; Pesetti, Barbara; Giorgio, Floriana; Moretti, Biagio; Resta, Leonardo; Rossi, Roberta; Annoscia, Emanuele; Patella, Vittorio; Notarnicola, Angela; Mallamaci, Rosanna; Francavilla, Antonio

    2009-08-01

    Mitochondrial DNA (mt-DNA) disorders and abnormal regulation of nuclear-derived proteins devoted to the cross-talk between the two cellular genomes have recently interested researchers in the field of neuromuscular diseases. We have identified, isolated and sequenced a new gene, augmenter of liver regeneration (ALR) that stimulates in vivo hepatocyte proliferation and up-regulates mt-DNA expression and ATP production. ALR protein (Alrp) is mainly located, in rat, in the mitochondrial inter-membrane space and its mRNA is particularly abundant in brain, muscle, testis and liver, tissues whose activity is mostly dependent on mitochondrial metabolism. Studies on rat Alrp sequence revealed the presence of homologous amino-acid sections into proteins derived from mouse, human, Drosophyla, plants and even DNA viruses. In this article, we evaluated ALR expression in normal human muscular tissues, both as protein and as mRNA. The data, obtained by molecular biology, immunohistochemistry and electron microscopy, demonstrated that: (i) Alrp and ALR mRNA are present in human muscular tissue; (ii) Alrp is particularly expressed in muscular fibres rich in mitochondria; (iii) Alrp is localized in the mitochondrial inter-membrane space or associated to mitochondrial cristae; and (iv) in subjects younger then 35 years of age, ALR mRNA expression is different between male and female subjects. In conclusion, the present data set Alrp, as a factor associated with mitochondria also in human tissue, call for future studies aimed at establishing Alrp as an important factor involved in the molecular events that trigger neuromuscular diseases.

  19. Expression and localization of augmenter of liver regeneration in human muscle tissue

    PubMed Central

    Lorenzo, Polimeno; Barbara, Pesetti; Floriana, Giorgio; Biagio, Moretti; Leonardo, Resta; Roberta, Rossi; Emanuele, Annoscia; Vittorio, Patella; Angela, Notarnicola; Rosanna, Mallamaci; Antonio, Francavilla

    2009-01-01

    Mitochondrial DNA (mt-DNA) disorders and abnormal regulation of nuclear-derived proteins devoted to the cross-talk between the two cellular genomes have recently interested researchers in the field of neuromuscular diseases. We have identified, isolated and sequenced a new gene, augmenter of liver regeneration (ALR) that stimulates in vivo hepatocyte proliferation and up-regulates mt-DNA expression and ATP production. ALR protein (Alrp) is mainly located, in rat, in the mitochondrial inter-membrane space and its mRNA is particularly abundant in brain, muscle, testis and liver, tissues whose activity is mostly dependent on mitochondrial metabolism. Studies on rat Alrp sequence revealed the presence of homologous amino-acid sections into proteins derived from mouse, human, Drosophyla, plants and even DNA viruses. In this article, we evaluated ALR expression in normal human muscular tissues, both as protein and as mRNA. The data, obtained by molecular biology, immunohistochemistry and electron microscopy, demonstrated that: (i) Alrp and ALR mRNA are present in human muscular tissue; (ii) Alrp is particularly expressed in muscular fibres rich in mitochondria; (iii) Alrp is localized in the mitochondrial inter-membrane space or associated to mitochondrial cristae; and (iv) in subjects younger then 35 years of age, ALR mRNA expression is different between male and female subjects. In conclusion, the present data set Alrp, as a factor associated with mitochondria also in human tissue, call for future studies aimed at establishing Alrp as an important factor involved in the molecular events that trigger neuromuscular diseases. PMID:19659900

  20. Lineage-Specific Regulation of Epigenetic Modifier Genes in Human Liver and Brain

    PubMed Central

    Weng, Matthias K.; Natarajan, Karthick; Scholz, Diana; Ivanova, Violeta N.; Sachinidis, Agapios; Hengstler, Jan G.; Waldmann, Tanja; Leist, Marcel

    2014-01-01

    Despite an abundance of studies on chromatin states and dynamics, there is an astonishing dearth of information on the expression of genes responsible for regulating histone and DNA modifications. We used here a set of 156 defined epigenetic modifier genes (EMG) and profiled their expression pattern in cells of different lineages. As reference value, expression data from human embryonic stem cells (hESC) were used. Hepatocyte-like cells were generated from hESC, and their EMG expression was compared to primary human liver cells. In parallel, we generated postmitotic human neurons (Lu d6), and compared their relative EMG expression to human cortex (Ctx). Clustering analysis of all cell types showed that neuronal lineage samples grouped together (94 similarly regulated EMG), as did liver cells (61 similarly-regulated), while the two lineages were clearly distinct. The general classification was followed by detailed comparison of the major EMG groups; genes that were higher expressed in differentiated cells than in hESC included the acetyltransferase KAT2B and the methyltransferase SETD7. Neuro-specific EMGs were the histone deacetylases HDAC5 and HDAC7, and the arginine-methyltransferase PRMT8. Comparison of young (Lu d6) and more aged (Ctx) neuronal samples suggested a maturation-dependent switch in the expression of functionally homologous proteins. For instance, the ratio of the histone H3 K27 methyltransfereases, EZH1 to EZH2, was high in Ctx and low in Lu d6. The same was observed for the polycomb repressive complex 1 (PRC1) subunits CBX7 and CBX8. A large proportion of EMGs in differentiated cells was very differently expressed than in hESC, and absolute levels were significantly higher in neuronal samples than in hepatic cells. Thus, there seem to be distinct qualitative and quantitative differences in EMG expression between cell lineages. PMID:25054330

  1. Interindividual variation in response to xenobiotic exposure established in precision-cut human liver slices.

    PubMed

    Jetten, Marlon J A; Claessen, Sandra M; Dejong, Cornelis H C; Lahoz, Agustin; Castell, José V; van Delft, Joost H M; Kleinjans, Jos C S

    2014-09-01

    Large differences in toxicity responses occur within the human population. In this study we evaluate whether interindividual variation in baseline enzyme activity (EA)/gene expression (GE) levels in liver predispose for the variation in toxicity responses by assessing dose-response relationships for several prototypical hepatotoxicants. Baseline levels of cytochrome-P450 (CYP) GE/EA were measured in precision-cut human liver slices. Slices (n=4-5/compound) were exposed to a dose-range of acetaminophen, aflatoxin B1, benzo(α) pyrene or 2-nitrofluorene. Interindividual variation in induced genotoxicity (COMET-assay and CDKN1A/p21 GE) and cytotoxicity (lactate dehydrogenase-leakage), combined with NQO1- and GSTM1-induced GE-responses for oxidative stress and GE-responses of several CYPs was evaluated. The benchmark dose-approach was applied as a tool to model exposure responses on an individual level. Variation in baseline CYP levels, both GE and EA, can explain variation in compound exposure-responses on an individual level. Network analyses enable the definition of key parameters influencing interindividual variation after compound exposure. For 2-nitrofluorene, this analysis suggests involvement of CYP1B1 in the metabolism of this compound, which represents a novel finding. In this study, GSTM1 which is known to be highly polymorphic within the human population, but so far could not be linked to toxicity in acetaminophen-poisoned patients, is suggested to cause interindividual variability in acetaminophen-metabolism, dependent on the individual's gene expression-responses of CYP-enzymes. This study demonstrates that using interindividual variation within network modelling provides a source for the definition of essential and even new parameters involved in compound-related metabolism. This information might enable ways to make more quantitative estimates of human risks. PMID:24949552

  2. Metabolism of (-)-cis- and (-)-trans-rose oxide by cytochrome P450 enzymes in human liver microsomes.

    PubMed

    Nakahashi, Hiroshi; Yamamura, Yuuki; Usami, Atsushi; Rangsunvigit, Pramoch; Malakul, Pomthong; Miyazawa, Mitsuo

    2015-12-01

    The in vitro metabolism of (-)-cis- and (-)-trans-rose oxide was investigated using human liver microsomes and recombinant cytochrome P450 (P450 or CYP) enzymes for the first time. Both isomers of rose oxide were incubated with human liver microsomes, and the formation of the respective 9-oxidized metabolite were determined using gas chromatography-mass spectrometry (GC-MS). Of 11 different recombinant human P450 enzymes used, CYP2B6 and CYP2C19 were the primary enzymes catalysing the metabolism of (-)-cis- and (-)-trans-rose oxide. CYP1A2 also efficiently oxidized (-)-cis-rose oxide at the 9-position but not (-)-trans-rose oxide. α-Naphthoflavone (a selective CYP1A2 inhibitor), thioTEPA (a CYP2B6 inhibitor) and anti-CYP2B6 antibody inhibited (-)-cis-rose oxide 9-hydroxylation catalysed by human liver microsomes. On the other hand, the metabolism of (-)-trans-rose oxide was suppressed by thioTEPA and anti-CYP2B6 at a significant level in human liver microsomes. However, omeprazole (a CYP2C19 inhibitor) had no significant effects on the metabolism of both isomers of rose oxide. Using microsomal preparations from nine different human liver samples, (-)-9-hydroxy-cis- and (-)-9-hydroxy-trans-rose oxide formations correlated with (S)-mephenytoin N-demethylase activity (CYP2B6 marker activity). These results suggest that CYP2B6 plays important roles in the metabolism of (-)-cis- and (-)-trans-rose oxide in human liver microsomes.

  3. Characterisation of liver pathogenesis, human immune responses and drug testing in a humanised mouse model of HCV infection

    PubMed Central

    Keng, Choong Tat; Sze, Ching Wooen; Zheng, Dahai; Zheng, Zhiqiang; Yong, Kylie Su Mei; Tan, Shu Qi; Ong, Jessica Jie Ying; Tan, Sue Yee; Loh, Eva; Upadya, Megha Haridas; Kuick, Chik Hong; Hotta, Hak; Lim, Seng Gee; Tan, Thiam Chye; Chang, Kenneth T E; Hong, Wanjin; Chen, Jianzhu; Tan, Yee-Joo; Chen, Qingfeng

    2016-01-01

    Objective HCV infection affects millions of people worldwide, and many patients develop chronic infection leading to liver cancers. For decades, the lack of a small animal model that can recapitulate HCV infection, its immunopathogenesis and disease progression has impeded the development of an effective vaccine and therapeutics. We aim to provide a humanised mouse model for the understanding of HCV-specific human immune responses and HCV-associated disease pathologies. Design Recently, we have established human liver cells with a matched human immune system in NOD-scid Il2rg−/− (NSG) mice (HIL mice). These mice are infected with HCV by intravenous injection, and the pathologies are investigated. Results In this study, we demonstrate that HIL mouse is capable of supporting HCV infection and can present some of the clinical symptoms found in HCV-infected patients including hepatitis, robust virus-specific human immune cell and cytokine responses as well as liver fibrosis and cirrhosis. Similar to results obtained from the analysis of patient samples, the human immune cells, particularly T cells and macrophages, play critical roles during the HCV-associated liver disease development in the HIL mice. Furthermore, our model is demonstrated to be able to reproduce the therapeutic effects of human interferon alpha 2a antiviral treatment. Conclusions The HIL mouse provides a model for the understanding of HCV-specific human immune responses and HCV-associated disease pathologies. It could also serve as a platform for antifibrosis and immune-modulatory drug testing. PMID:26149491

  4. Hydrolysis of pyrethroids by human and rat tissues: Examination of intestinal, liver and serum carboxylesterases

    SciTech Connect

    Crow, J. Allen; Borazjani, Abdolsamad; Potter, Philip M.; Ross, Matthew K. . E-mail: mross@cvm.msstate.edu

    2007-05-15

    Hydrolytic metabolism of pyrethroid insecticides in humans is one of the major catabolic pathways that clear these compounds from the body. Rodent models are often used to determine the disposition and clearance rates of these esterified compounds. In this study the distribution and activities of esterases that catalyze pyrethroid metabolism have been investigated in vitro using several human and rat tissues, including small intestine, liver and serum. The major esterase in human intestine is carboxylesterase 2 (hCE2). We found that the pyrethroid trans-permethrin is effectively hydrolyzed by a sample of pooled human intestinal microsomes (5 individuals), while deltamethrin and bioresmethrin are not. This result correlates well with the substrate specificity of recombinant hCE2 enzyme. In contrast, a sample of pooled rat intestinal microsomes (5 animals) hydrolyze trans-permethrin 4.5-fold slower than the sample of human intestinal microsomes. Furthermore, it is demonstrated that pooled samples of cytosol from human or rat liver are {approx} 2-fold less hydrolytically active (normalized per mg protein) than the corresponding microsomal fraction toward pyrethroid substrates; however, the cytosolic fractions do have significant amounts ({approx} 40%) of the total esteratic activity. Moreover, a 6-fold interindividual variation in carboxylesterase 1 protein expression in human hepatic cytosols was observed. Human serum was shown to lack pyrethroid hydrolytic activity, but rat serum has hydrolytic activity that is attributed to a single CE isozyme. We purified the serum CE enzyme to homogeneity to determine its contribution to pyrethroid metabolism in the rat. Both trans-permethrin and bioresmethrin were effectively cleaved by this serum CE, but deltamethrin, esfenvalerate, alpha-cypermethrin and cis-permethrin were slowly hydrolyzed. Lastly, two model lipase enzymes were examined for their ability to hydrolyze pyrethroids. However, no hydrolysis products could be

  5. Ischaemic Preconditioning and Intermittent Clamping Does not Influence Mediators of Liver Regeneration in a Human Liver Sinusoidal Endothelial Cell Model of Ischaemia-Reperfusion Injury

    PubMed Central

    Gomez, Dhanwant; Burn, J.. Lance; Graham, Ann; Homer-Vanniasinkam, Shervanthi; Prasad, K.. Rajendra

    2012-01-01

    Background The role of surgical technique on liver regeneration following surgery remains inconclusive. The aim of the study was to assess the effect of ischaemic preconditioning (IPC) and intermittent clamping (IC) on mediators of regeneration produced by human liver sinusoidal endothelial cells (SECs), using an in vitro hypoxia-reoxygenation model to mimic ischaemia-reperfusion injury (IRI). Methods Following extraction from samples obtained from liver resection (n = 5), confluent culture flasks of SECs were subjected to IRI (1 hour hypoxia + 1 hour reoxygenation), IPC prior to IRI (10 minutes hypoxia + 10 minutes reoxygenation + 1 hour hypoxia + 1 hour reoxygenation), IC (15 minutes hypoxia + 5 minutes reoxygenation x 3 + 1 hour reoxygenation) and compared to controls. The production of various mediators was determined over 48 hours. Results Interleukin (IL)-6, IL-8, granulocyte-colony stimulating factor (G-CSF) and hepatocyte growth factor (HGF) were produced by SECs. Both IPC and IC did not significantly influence the profile of IL-6, IL-8, G-CSF and HGF by SECs compared to IRI over the study period. Conclusion IPC and IC did not influence the production of pro-regenerative mediators in a SECs model of IRI. The role of surgical technique on liver regeneration remains to be determined.

  6. Studying Closed Hydrodynamic Models of “In Vivo” DNA Perfusion in Pig Liver for Gene Therapy Translation to Humans

    PubMed Central

    Sendra, Luis; Miguel, Antonio; Pérez-Enguix, Daniel; Montalvá, Eva; García-Gimeno, María Adelaida; Noguera, Inmaculada; Díaz, Ana; Pérez, Judith; Sanz, Pascual; López-Andújar, Rafael; Martí-Bonmatí, Luis; Aliño, Salvador F.

    2016-01-01

    Introduction Expressing exogenous genes after naked DNA delivery into hepatocytes might achieve sustained and high expression of human proteins. Tail vein DNA injection is an efficient procedure for gene transfer in murine liver. Hydrodynamic procedures in large animals require organ targeting, and improve with liver vascular exclusion. In the present study, two closed liver hydrofection models employing the human alpha-1-antitrypsin (hAAT) gene are compared to reference standards in order to evaluate their potential clinical interest. Material and Methods A solution of naked DNA bearing the hAAT gene was retrogradely injected in 7 pig livers using two different closed perfusion procedures: an endovascular catheterization-mediated procedure (n = 3) with infrahepatic inferior vena cava and portal vein blockage; and a surgery-mediated procedure (n = 4) with completely sealed liver. Gene transfer was performed through the suprahepatic inferior cava vein in the endovascular procedure and through the infrahepatic inferior vena cava in the surgical procedure. The efficiency of the procedures was evaluated 14 days after hydrofection by quantifying the hAAT protein copies per cell in tissue and in plasma. For comparison, samples from mice (n = 7) successfully hydrofected with hAAT and healthy human liver segments (n = 4) were evaluated. Results Gene decoding occurs efficiently using both procedures, with liver vascular arrest improving its efficiency. The surgically closed procedure (sealed organ) reached higher tissue protein levels (4x10^5- copies/cell) than the endovascular procedure, though the levels were lower than in human liver (5x10^6- copies/cell) and hydrofected mouse liver (10^6- copies/cell). However, protein levels in plasma were lower (p<0.001) than the reference standards in all cases. Conclusion Hydrofection of hAAT DNA to “in vivo” isolated pig liver mediates highly efficient gene delivery and protein expression in tissue. Both endovascular and

  7. Acetaminophen cytotoxicity is ameliorated in a human liver organotypic co-culture model.

    PubMed

    Nelson, Leonard J; Navarro, Maria; Treskes, Philipp; Samuel, Kay; Tura-Ceide, Olga; Morley, Steven D; Hayes, Peter C; Plevris, John N

    2015-01-01

    Organotypic liver culture models for hepatotoxicity studies that mimic in vivo hepatic functionality could help facilitate improved strategies for early safety risk assessment during drug development. Interspecies differences in drug sensitivity and mechanistic profiles, low predictive capacity, and limitations of conventional monocultures of human hepatocytes, with high attrition rates remain major challenges. Herein, we show stable, cell-type specific phenotype/cellular polarity with differentiated functionality in human hepatocyte-like C3A cells (enhanced CYP3A4 activity/albumin synthesis) when in co-culture with human vascular endothelial cells (HUVECs), thus demonstrating biocompatibility and relevance for evaluating drug metabolism and toxicity. In agreement with in vivo studies, acetaminophen (APAP) toxicity was most profound in HUVEC mono-cultures; whilst in C3A:HUVEC co-culture, cells were less susceptible to the toxic effects of APAP, including parameters of oxidative stress and ATP depletion, altered redox homeostasis, and impaired respiration. This resistance to APAP is also observed in a primary human hepatocyte (PHH) based co-culture model, suggesting bidirectional communication/stabilization between different cell types. This simple and easy-to-implement human co-culture model may represent a sustainable and physiologically-relevant alternative cell system to PHHs, complementary to animal testing, for initial hepatotoxicity screening or mechanistic studies of candidate compounds differentially targeting hepatocytes and endothelial cells. PMID:26632255

  8. Disease modeling using human induced pluripotent stem cells: lessons from the liver.

    PubMed

    Gieseck, Richard L; Colquhoun, Jennifer; Hannan, Nicholas R F

    2015-01-01

    Human pluripotent stem cells (hPSCs) have the capacity to differentiate into any of the hundreds of distinct cell types that comprise the human body. This unique characteristic has resulted in considerable interest in the field of regenerative medicine, given the potential for these cells to be used to protect, repair, or replace diseased, injured, and aged cells within the human body. In addition to their potential in therapeutics, hPSCs can be used to study the earliest stages of human development and to provide a platform for both drug screening and disease modeling using human cells. Recently, the description of human induced pluripotent stem cells (hIPSCs) has allowed the field of disease modeling to become far more accessible and physiologically relevant, as pluripotent cells can be generated from patients of any genetic background. Disease models derived from hIPSCs that manifest cellular disease phenotypes have been established to study several monogenic diseases; furthermore, hIPSCs can be used for phenotype-based drug screens to investigate complex diseases for which the underlying genetic mechanism is unknown. As a result, the use of stem cells as research tools has seen an unprecedented growth within the last decade as researchers look for in vitro disease models which closely mimic in vivo responses in humans. Here, we discuss the beginnings of hPSCs, starting with isolation of human embryonic stem cells, moving into the development and optimization of hIPSC technology, and ending with the application of hIPSCs towards disease modeling and drug screening applications, with specific examples highlighting the modeling of inherited metabolic disorders of the liver. This article is part of a Special Issue entitled Linking transcription to physiology in lipodomics.

  9. Sodium taurocholate cotransporting polypeptide inhibition efficiently blocks hepatitis B virus spread in mice with a humanized liver.

    PubMed

    Nakabori, Tasuku; Hikita, Hayato; Murai, Kazuhiro; Nozaki, Yasutoshi; Kai, Yugo; Makino, Yuki; Saito, Yoshinobu; Tanaka, Satoshi; Wada, Hiroshi; Eguchi, Hidetoshi; Takahashi, Takeshi; Suemizu, Hiroshi; Sakamori, Ryotaro; Hiramatsu, Naoki; Tatsumi, Tomohide; Takehara, Tetsuo

    2016-01-01

    Sodium taurocholate cotransporting polypeptide (NTCP) is a recently discovered hepatitis B virus (HBV) receptor. In the present study, we used TK-NOG mice with a humanized liver to examine the impact of endogenous NTCP expression on HBV infection. Upon inoculation with HBV, these mice exhibited clear viremia in 2 weeks, and serum HBV DNA levels gradually increased. The frequency of HBsAg-positive hepatocytes in the liver was 5.1 ± 0.6% at 2 weeks and increased with increasing HBV DNA levels, reaching 92.9 ± 2.8% at 10 to 12 weeks. In vivo siRNA-mediated NTCP knockdown before and after HBV inoculation significantly suppressed the levels of HBV replication and the frequency of HBsAg-positive hepatocytes at 2 weeks, whereas NTCP knockdown 13 weeks after infection did not affect these parameters. Similar to the humanized mouse livers in the early phase of HBV infection, human liver samples from chronic hepatitis B patients, especially those treated with nucleos(t)ide analogues, contained a considerable number of hepatocytes that were negative for the anti-HBs antibody. In conclusion, NTCP inhibition prevents the spread of HBV-infected hepatocytes in mice with a humanized liver. NTCP-targeted therapy has potential for regulating HBV infection in patients with chronic hepatitis B.

  10. Chemoprevention and cytotoxic effect of Bauhinia variegata against N-nitrosodiethylamine induced liver tumors and human cancer cell lines.

    PubMed

    Rajkapoor, B; Jayakar, B; Murugesh, N; Sakthisekaran, D

    2006-04-01

    The chemopreventive and cytotoxic effect of ethanol extract of Bauhinia variegata (EBV) was evaluated in N-nitrosodiethylamine (DEN, 200 mg/kg) induced experimental liver tumor in rats and human cancer cell lines. Oral administration of ethanol extract of Bauhinia variegata (250 mg/kg) effectively suppressed liver tumor induced by DEN as revealed by decrease in DEN induced elevated levels of serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), total bilirubin, gamma glutamate transpeptidase (GGTP), lipid peroxidase (LPO), glutathione peroxidase (GPx) and glutathione S-transferase (GST). The extract produced an increase in enzymatic antioxidant (superoxide dismutase and catalase) levels and total proteins when compared to those in liver tumor bearing rats. The histopathological changes of liver samples were compared with respective controls. EBV was found to be cytotoxic against human epithelial larynx cancer (HEp2) and human breast cancer (HBL-100) cells. These results show a significant chemopreventive and cytotoxic effect of ethanol extract of Bauhinia variegata against DEN induced liver tumor and human cancer cell lines.

  11. Exacerbating Effects of Human Parvovirus B19 NS1 on Liver Fibrosis in NZB/W F1 Mice

    PubMed Central

    Hsu, Tsai-Ching; Tsai, Chun-Chou; Chiu, Chun-Ching; Hsu, Jeng-Dong; Tzang, Bor-Show

    2013-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disorder with unknown etiology that impacts various organs including liver. Recently, human parvovirus B19 (B19) is recognized to exacerbate SLE. However, the effects of B19 on liver in SLE are still unclear. Herein we aimed to investigate the effects of B19 on liver in NZB/W F1 mice by injecting subcutaneously with PBS, recombinant B19 NS1, VP1u or VP2, respectively. Our experimental results revealed that B19 NS1 protein significantly enhanced the TGF-β/Smad fibrotic signaling by increasing the expressions of TGF-β, Smad2/3, phosphorylated Smad2/3, Smad4 and Sp1. The consequent fibrosis-related proteins, PAI-1 and α-SMA, were also significantly induced in livers of NZB/W F1 mice receiving B19 NS1 protein. Accordingly, markedly increased collagen deposition was also observed in livers of NZB/W F1 mice receiving B19 NS1 protein. However, no significant difference was observed in livers of NZB/W F1 mice receiving B19 VP1u or VP2 as compared to the controls. These findings indicate that B19 NS1 plays a crucial role in exacerbating liver fibrosis in NZB/W F1 mice through enhancing the TGF-â/Smad fibrotic signaling. PMID:23840852

  12. Exacerbating effects of human parvovirus B19 NS1 on liver fibrosis in NZB/W F1 mice.

    PubMed

    Hsu, Tsai-Ching; Tsai, Chun-Chou; Chiu, Chun-Ching; Hsu, Jeng-Dong; Tzang, Bor-Show

    2013-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disorder with unknown etiology that impacts various organs including liver. Recently, human parvovirus B19 (B19) is recognized to exacerbate SLE. However, the effects of B19 on liver in SLE are still unclear. Herein we aimed to investigate the effects of B19 on liver in NZB/W F1 mice by injecting subcutaneously with PBS, recombinant B19 NS1, VP1u or VP2, respectively. Our experimental results revealed that B19 NS1 protein significantly enhanced the TGF-β/Smad fibrotic signaling by increasing the expressions of TGF-β, Smad2/3, phosphorylated Smad2/3, Smad4 and Sp1. The consequent fibrosis-related proteins, PAI-1 and α-SMA, were also significantly induced in livers of NZB/W F1 mice receiving B19 NS1 protein. Accordingly, markedly increased collagen deposition was also observed in livers of NZB/W F1 mice receiving B19 NS1 protein. However, no significant difference was observed in livers of NZB/W F1 mice receiving B19 VP1u or VP2 as compared to the controls. These findings indicate that B19 NS1 plays a crucial role in exacerbating liver fibrosis in NZB/W F1 mice through enhancing the TGF-â/Smad fibrotic signaling.

  13. Cellular localization of type I III and IV procollagen gene transcripts in normal and fibrotic human liver.

    PubMed Central

    Milani, S.; Herbst, H.; Schuppan, D.; Surrenti, C.; Riecken, E. O.; Stein, H.

    1990-01-01

    The authors have determined the cell types producing alpha 1 (I), alpha 2 (I), alpha 1 (III), and alpha 1 (IV) procollagen gene transcripts in adult human liver by in situ hybridization with [35S]-labeled RNA probes. The liver specimens comprised a total of 20 biopsies with normal histology and biopsies with fibrosis or cirrhosis at different clinical stages and of heterogeneous origins. In normal liver, procollagen type I, III, and IV transcripts were detected in stromal and vascular mesenchymal cells of portal tracts and central veins, as well as in some perisinusoidal cells of the lobule. In fibrotic liver, increased levels of these procollagen mRNAs were observed in the same locations, and particularly enhanced in stromal cells of fibrotic septa and portal tracts, as well as in perisinusoidal cells. Expression of alpha 1 (IV) procollagen RNA was additionally found in some vascular endothelial and bile duct epithelial cells. Although previously suggested as the major source of liver collagens, hepatocytes showed no significant procollagen transcript levels in any of our samples. Thus, procollagen synthesis does not appear to be a function of hepatocytes, but rather of mesenchymal, endothelial, and bile duct epithelial cells in adult human liver. These findings may have implications for the development of specifically targeted antifibrotic therapies. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:2372043

  14. Stiffness of hyaluronic acid gels containing liver extracellular matrix supports human hepatocyte function and alters cell morphology.

    PubMed

    Deegan, Daniel B; Zimmerman, Cynthia; Skardal, Aleksander; Atala, Anthony; Shupe, Thomas D

    2015-03-01

    Tissue engineering and cell based liver therapies have utilized primary hepatocytes with limited success due to the failure of hepatocytes to maintain their phenotype in vitro. In order to overcome this challenge, hyaluronic acid (HA) cell culture substrates were formulated to closely mimic the composition and stiffness of the normal liver cellular microenvironment. The stiffness of the substrate was modulated by adjusting HA hydrogel crosslinking. Additionally, the repertoire of bioactive molecules within the HA substrate was bolstered by supplementation with normal liver extracellular matrix (ECM). Primary human hepatocyte viability and phenotype were determined over a narrow physiologically relevant range of substrate stiffnesses from 600 to 4600Pa in both the presence and absence of liver ECM. Cell attachment, viability, and organization of the actin cytoskeleton improved with increased stiffness up to 4600Pa. These differences were not evident in earlier time points or substrates containing only HA. However, gene expression for the hepatocyte markers hepatocyte nuclear factor 4 alpha (HNF4α) and albumin significantly decreased on the 4600Pa stiffness at day 7 indicating that cells may not have maintained their phenotype long-term at this stiffness. Function, as measured by albumin secretion, varied with both stiffness and time in culture and peaked at day 7 at the 1200Pa stiffness, slightly below the stiffness of normal liver ECM at 3000Pa. Overall, gel stiffness affected primary human hepatocyte cell adhesion, functional marker expression, and morphological characteristics dependent on both the presence of liver ECM in gel substrates and time in culture.

  15. Turnover Rates of Hepatic Collagen and Circulating Collagen-Associated Proteins in Humans with Chronic Liver Disease

    PubMed Central

    Li, Kelvin; Gatmaitan, Michelle; Luo, Flora; Cattin, Jerome; Nakamura, Corelle; Holmes, William E.; Angel, Thomas E.; Peters, Marion G.; Turner, Scott M.; Hellerstein, Marc K.

    2015-01-01

    Accumulation and degradation of scar tissue in fibrotic liver disease occur slowly, typically over many years. Direct measurement of fibrogenesis, the rate of scar tissue deposition, may provide valuable therapeutic and prognostic information. We describe here results from a pilot study utilizing in vivo metabolic labeling to measure the turnover rate of hepatic collagen and collagen-associated proteins in plasma for the first time in human subjects. Eight subjects with chronic liver disease were labeled with daily oral doses of 2H2O for up to 8 weeks prior to diagnostic liver biopsy and plasma collection. Tandem mass spectrometry was used to measure the abundance and fractional synthesis rate (FSR) of proteins in liver and blood. Relative protein abundance and FSR data in liver revealed marked differences among subjects. FSRs of hepatic type I and III collagen ranged from 0.2–0.6% per day (half-lives of 4 months to a year) and correlated significantly with worsening histologic fibrosis. Analysis of plasma protein turnover revealed two collagen-associated proteins, lumican and transforming growth factor beta-induced-protein (TGFBI), exhibiting FSRs that correlated significantly with FSRs of hepatic collagen. In summary, this is the first direct measurement of liver collagen turnover in vivo in humans and suggests a high rate of collagen remodeling in advanced fibrosis. In addition, the FSRs of collagen-associated proteins in plasma are measurable and may provide a novel strategy for monitoring hepatic fibrogenesis rates. PMID:25909381

  16. Stiffness of hyaluronic acid gels containing liver extracellular matrix supports human hepatocyte function and alters cell morphology.

    PubMed

    Deegan, Daniel B; Zimmerman, Cynthia; Skardal, Aleksander; Atala, Anthony; Shupe, Thomas D

    2015-03-01

    Tissue engineering and cell based liver therapies have utilized primary hepatocytes with limited success due to the failure of hepatocytes to maintain their phenotype in vitro. In order to overcome this challenge, hyaluronic acid (HA) cell culture substrates were formulated to closely mimic the composition and stiffness of the normal liver cellular microenvironment. The stiffness of the substrate was modulated by adjusting HA hydrogel crosslinking. Additionally, the repertoire of bioactive molecules within the HA substrate was bolstered by supplementation with normal liver extracellular matrix (ECM). Primary human hepatocyte viability and phenotype were determined over a narrow physiologically relevant range of substrate stiffnesses from 600 to 4600Pa in both the presence and absence of liver ECM. Cell attachment, viability, and organization of the actin cytoskeleton improved with increased stiffness up to 4600Pa. These differences were not evident in earlier time points or substrates containing only HA. However, gene expression for the hepatocyte markers hepatocyte nuclear factor 4 alpha (HNF4α) and albumin significantly decreased on the 4600Pa stiffness at day 7 indicating that cells may not have maintained their phenotype long-term at this stiffness. Function, as measured by albumin secretion, varied with both stiffness and time in culture and peaked at day 7 at the 1200Pa stiffness, slightly below the stiffness of normal liver ECM at 3000Pa. Overall, gel stiffness affected primary human hepatocyte cell adhesion, functional marker expression, and morphological characteristics dependent on both the presence of liver ECM in gel substrates and time in culture. PMID:26569044

  17. Detection of human herpesvirus-7 by qualitative nested-PCR: comparison between healthy individuals and liver transplant recipients.

    PubMed

    Thomasini, Ronaldo Luis; Martins, Juliana de Moraes; Parola, Daniela Corte; Bonon, Sandra Helena Alves; Boin, Ilka de Fátima Santana Ferreira; Leonardi, Luis Sérgio; Leonardi, Marília; Costa, Sandra Cecília Botelho

    2008-01-01

    Diagnosis of human herpesvirus-7 active infection in transplant patients has proved difficult, because this virus is ubiquitous and can cause persistent infections in the host. The significance of viral DNA detected in leukocytes by PCR is unclear and cross-reaction in serological tests may occur. This study aimed to evaluate nested-PCR to detect human herpesvirus-7 active infection in liver transplant recipients compared to healthy individuals. human herpesvirus-7 nested-PCR was performed on leukocytes and sera of 53 healthy volunteers and sera of 29 liver transplant recipients. In healthy volunteers, human herpesvirus-7 was detected in 28.3% of leukocytes and 0% of serum. human herpesvirus-7 was detected in sera of 48.2% of the liver transplant recipients. Nested-PCR on DNA extracted from leukocytes detected latent infection and the study suggests that nested-PCR performed on serum could be useful to detect human herpesvirus-7 active infection in liver transplant recipients. PMID:19142431

  18. Effects of iron and copper overload on the human liver: an ultrastructural study.

    PubMed

    Fanni, D; Fanos, V; Gerosa, C; Piras, M; Dessi, A; Atzei, A; Van, Eyken P; Gibo, Y; Faa, G

    2014-01-01

    Iron and copper ions play important roles in many physiological functions of our body, even though the exact mechanisms regulating their absorption, distribution and excretion are not fully understood. Metal-related human pathology may be observed in two different clinical settings: deficiency or overload. The overload in liver cells of both trace elements leads to multiple cellular lesions. Here we report the main pathological changes observed at transmission electron microscopy in the liver of subjects affected by Beta-thalassemia and by Wilson's disease. The hepatic iron overload in beta-thalassemia patients is associated with haemosiderin storage both in Kupffer cells and in the cytoplasm of hepatocytes. Haemosiderin granules are grouped inside voluminous lysosomes, also called siderosomes. Other ultrastructural changes are fat droplets, proliferation of the smooth endoplasmic reticulum and fibrosis. Apoptosis of hepatocytes and infiltration of sinusoids by polymorphonucleates is also detected in beta-thalassemia. Ultrastructural changes in liver biopsies from Wilson's disease patients are characterized by severe mitochondrial changes, associated with an increased number of perossisomes, cytoplasmic lipid droplets and the presence of lipolysosomes, characteristic cytoplasmic bodies formed by lipid vacuoles surrounded by electron-dense lysosomes. In patients affected by Wilson's disease, nuclei are frequently involved, with disorganization of the nucleoplasm and with glycogen inclusions. On the contrary, no significant changes are detected in Kupffer cells. Our data show that iron and copper, even though are both transition metals, are responsible of different pathological changes at ultrastructural level. In particular, copper overload is associated with mitochondrial damage, whereas iron overload only rarely may cause severe mitochondrial changes. These differences underlay the need for further studies in which biochemical analyses should be associated with

  19. System-based proteomic analysis of the interferon response in human liver cells

    PubMed Central

    Yan, Wei; Lee, Hookeun; Yi, Eugene C; Reiss, David; Shannon, Paul; Kwieciszewski, Bartlomiej K; Coito, Carlos; Li, Xiao-jun; Keller, Andrew; Eng, Jimmy; Galitski, Timothy; Goodlett, David R; Aebersold, Ruedi; Katze, Michael G

    2004-01-01

    Background Interferons (IFNs) play a critical role in the host antiviral defense and are an essential component of current therapies against hepatitis C virus (HCV), a major cause of liver disease worldwide. To examine liver-specific responses to IFN and begin to elucidate the mechanisms of IFN inhibition of virus replication, we performed a global quantitative proteomic analysis in a human hepatoma cell line (Huh7) in the presence and absence of IFN treatment using the isotope-coded affinity tag (ICAT) method and tandem mass spectrometry (MS/MS). Results In three subcellular fractions from the Huh7 cells treated with IFN (400 IU/ml, 16 h) or mock-treated, we identified more than 1,364 proteins at a threshold that corresponds to less than 5% false-positive error rate. Among these, 54 were induced by IFN and 24 were repressed by more than two-fold, respectively. These IFN-regulated proteins represented multiple cellular functions including antiviral defense, immune response, cell metabolism, signal transduction, cell growth and cellular organization. To analyze this proteomics dataset, we utilized several systems-biology data-mining tools, including Gene Ontology via the GoMiner program and the Cytoscape bioinformatics platform. Conclusions Integration of the quantitative proteomics with global protein interaction data using the Cytoscape platform led to the identification of several novel and liver-specific key regulatory components of the IFN response, which may be important in regulating the interplay between HCV, interferon and the host response to virus infection. PMID:15287976

  20. Interaction of perfluoroalkyl acids with human liver fatty acid-binding protein.

    PubMed

    Sheng, Nan; Li, Juan; Liu, Hui; Zhang, Aiqian; Dai, Jiayin

    2016-01-01

    Perfluoroalkyl acids (PFAAs) are highly persistent and bioaccumulative, resulting in their broad distribution in humans and the environment. The liver is an important target for PFAAs, but the mechanisms behind PFAAs interaction with hepatocyte proteins remain poorly understood. We characterized the binding of PFAAs to human liver fatty acid-binding protein (hL-FABP) and identified critical structural features in their interaction. The binding interaction of PFAAs with hL-FABP was determined by fluorescence displacement and isothermal titration calorimetry (ITC) assay. Molecular simulation was conducted to define interactions at the binding sites. ITC measurement revealed that PFOA/PFNA displayed a moderate affinity for hL-FABP at a 1:1 molar ratio, a weak binding affinity for PFHxS and no binding for PFHxA. Moreover, the interaction was mainly mediated by electrostatic attraction and hydrogen bonding. Substitution of Asn111 with Asp caused loss of binding affinity to PFAA, indicating its crucial role for the initial PFAA binding to the outer binding site. Substitution of Arg122 with Gly caused only one molecule of PFAA to bind to hL-FABP. Molecular simulation showed that substitution of Arg122 increased the volume of the outer binding pocket, making it impossible to form intensive hydrophobic stacking and hydrogen bonds with PFOA, and highlighting its crucial role in the binding process. The binding affinity of PFAAs increased significantly with their carbon number. Arg122 and Asn111 played a pivotal role in these interactions. Our findings may help understand the distribution pattern, bioaccumulation, elimination, and toxicity of PFAAs in humans.

  1. Cadmium Chloride Induces DNA Damage and Apoptosis of Human Liver Carcinoma Cells via Oxidative Stress

    PubMed Central

    Skipper, Anthony; Sims, Jennifer N.; Yedjou, Clement G.; Tchounwou, Paul B.

    2016-01-01

    Cadmium is a heavy metal that has been shown to cause its toxicity in humans and animals. Many documented studies have shown that cadmium produces various genotoxic effects such as DNA damage and chromosomal aberrations. Ailments such as bone disease, renal damage, and several forms of cancer are attributed to overexposure to cadmium.  Although there have been numerous studies examining the effects of cadmium in animal models and a few case studies involving communities where cadmium contamination has occurred, its molecular mechanisms of action are not fully elucidated. In this research, we hypothesized that oxidative stress plays a key role in cadmium chloride-induced toxicity, DNA damage, and apoptosis of human liver carcinoma (HepG2) cells. To test our hypothesis, cell viability was determined by MTT assay. Lipid hydroperoxide content stress was estimated by lipid peroxidation assay. Genotoxic damage was tested by the means of alkaline single cell gel electrophoresis (Comet) assay. Cell apoptosis was measured by flow cytometry assessment (Annexin-V/PI assay). The result of MTT assay indicated that cadmium chloride induces toxicity to HepG2 cells in a concentration-dependent manner, showing a 48 hr-LD50 of 3.6 µg/mL. Data generated from lipid peroxidation assay resulted in a significant (p < 0.05) increase of hydroperoxide production, specifically at the highest concentration tested. Data obtained from the Comet assay indicated that cadmium chloride causes DNA damage in HepG2 cells in a concentration-dependent manner. A strong concentration-response relationship (p < 0.05) was recorded between annexin V positive cells and cadmium chloride exposure. In summary, these in vitro studies provide clear evidence that cadmium chloride induces oxidative stress, DNA damage, and programmed cell death in human liver carcinoma (HepG2) cells. PMID:26729151

  2. Neoplastic lesions of the human liver in relation to the activity of the cytochrome P-450 dependent monooxygenase system.

    PubMed

    Plewka, D; Plewka, A; Nowaczyk, G; Kamiński, M; Rutkowski, T; Ludyga, T; Ziaja, K

    2000-01-01

    We studied the activity of Mixed function oxidase (MFO) in human livers affected by cancer. We determined the content of cytochrome P-450 and b5, as well as the activity of their corresponding reductases, according to generally accepted methods. Liver fragments corresponding with a) healthy tissue, b) tissue at the cancer border and, c) cancerous tissue were collected during surgery from patients with liver cancer. We noted that the developing liver cancer decreased the level of cytochrome P-450, even by a magnitude order. The activity of its corresponding reductase was higher in cancerous than in healthy tissues. Cytochrome b5 behaved in an analogous manner, although the decrease in its content was less significant. NADH-cytochrome b5 reductase activity changes were insignificant.

  3. [Progress in quantitative methods based on liquid chromatography-mass spectrometry for drug metabolizing enzymes in human liver microsomes].

    PubMed

    Wang, Huanhuan; Lu, Yayao; Peng, Bo; Qian, Xiaohong; Zhang, Yangjun

    2015-06-01

    Cytochrome P450 (CYP) enzymes and uridine 5-diphospho-glucuronosyltransferase (UGT) enzymes are critical enzymes for drug metabolism. Both chemical drugs and traditional Chinese medicines are converted to more readily excreted compounds by drug metabolizing enzymes in human livers. Because of the disparate expression of CYP and UGT enzymes among different individuals, accurate quantification of these enzymes is essential for drug pharmacology, drug-drug interactions and drug clinical applications. The research progress in quantitative methods based on liquid chromatography-mass spectrometry for drug metabolizing enzymes in human liver microsomes in the recent decade is reviewed. PMID:26536756

  4. [Progress in quantitative methods based on liquid chromatography-mass spectrometry for drug metabolizing enzymes in human liver microsomes].

    PubMed

    Wang, Huanhuan; Lu, Yayao; Peng, Bo; Qian, Xiaohong; Zhang, Yangjun

    2015-06-01

    Cytochrome P450 (CYP) enzymes and uridine 5-diphospho-glucuronosyltransferase (UGT) enzymes are critical enzymes for drug metabolism. Both chemical drugs and traditional Chinese medicines are converted to more readily excreted compounds by drug metabolizing enzymes in human livers. Because of the disparate expression of CYP and UGT enzymes among different individuals, accurate quantification of these enzymes is essential for drug pharmacology, drug-drug interactions and drug clinical applications. The research progress in quantitative methods based on liquid chromatography-mass spectrometry for drug metabolizing enzymes in human liver microsomes in the recent decade is reviewed.

  5. Human liver apolipoprotein B-100 cDNA: complete nucleic acid and derived amino acid sequence.

    PubMed Central

    Law, S W; Grant, S M; Higuchi, K; Hospattankar, A; Lackner, K; Lee, N; Brewer, H B

    1986-01-01

    Human apolipoprotein B-100 (apoB-100), the ligand on low density lipoproteins that interacts with the low density lipoprotein receptor and initiates receptor-mediated endocytosis and low density lipoprotein catabolism, has been cloned, and the complete nucleic acid and derived amino acid sequences have been determined. ApoB-100 cDNAs were isolated from normal human liver cDNA libraries utilizing immunoscreening as well as filter hybridization with radiolabeled apoB-100 oligodeoxynucleotides. The apoB-100 mRNA is 14.1 kilobases long encoding a mature apoB-100 protein of 4536 amino acids with a calculated amino acid molecular weight of 512,723. ApoB-100 contains 20 potential glycosylation sites, and 12 of a total of 25 cysteine residues are located in the amino-terminal region of the apolipoprotein providing a potential globular structure of the amino terminus of the protein. ApoB-100 contains relatively few regions of amphipathic helices, but compared to other human apolipoproteins it is enriched in beta-structure. The delineation of the entire human apoB-100 sequence will now permit a detailed analysis of the conformation of the protein, the low density lipoprotein receptor binding domain(s), and the structural relationship between apoB-100 and apoB-48 and will provide the basis for the study of genetic defects in apoB-100 in patients with dyslipoproteinemias. PMID:3464946

  6. Identification and characterization of metabolites of ASP015K, a novel oral Janus kinase inhibitor, in rats, chimeric mice with humanized liver, and humans.

    PubMed

    Nakada, Naoyuki; Oda, Kazuo

    2015-01-01

    1. Here, we elucidated the structure of metabolites of novel oral Janus kinase inhibitor ASP015K in rats and humans and evaluated the predictability of human metabolites using chimeric mice with humanized liver (PXB mice). 2. Rat biological samples collected after oral dosing of (14)C-labelled ASP015K were examined using a liquid chromatography-radiometric detector and mass spectrometer (LC-RAD/MS). The molecular weight of metabolites in human and the liver chimeric mouse biological samples collected after oral dosing of non-labelled ASP015K was also investigated via LC-MS. Metabolites were also isolated from rat bile samples and analyzed using nuclear magnetic resonance. 3. Metabolic pathways of ASP015K in rats and humans were found to be glucuronide conjugation, methyl conjugation, sulfate conjugation, glutathione conjugation, hydroxylation of the adamantane ring and N-oxidation of the 1H-pyrrolo[2,3-b]pyridine ring. The main metabolite of ASP015K in rats was the glucuronide conjugate, while the main metabolite in humans was the sulfate conjugate. Given that human metabolites were produced by human hepatocytes in chimeric mice with humanized liver, this human model mouse was believed to be useful in predicting the human metabolic profile of various drug candidates.

  7. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation.

    PubMed

    Bruno, Stefania; Grange, Cristina; Tapparo, Marta; Pasquino, Chiara; Romagnoli, Renato; Dametto, Ennia; Amoroso, Antonio; Tetta, Ciro; Camussi, Giovanni

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell contact and dependent on the release of prostaglandin E2 (PGE2) and on indoleamine 2,3-dioxygenase activity. When compared with mesenchymal stromal cells (MSCs), HLSCs were more efficient in inhibiting T-cell proliferation. At variance with MSCs, HLSCs did not elicit NK degranulation. Moreover, HLSCs inhibited NK degranulation against K562, a NK-sensitive target, by a mechanism dependent on HLA-G release. When tested on DC generation from monocytes, HLSCs were found to impair DC differentiation and DCs ability to induce T-cell proliferation through PGE2. This study shows that HLSCs have immunomodulatory properties similar to MSCs, but, at variance with MSCs, they do not elicit a NK response. PMID:27127520

  8. Altered action of glucagon on human liver in type 2 (non-insulin-dependent) diabetes mellitus.

    PubMed

    Arner, P; Einarsson, K; Ewerth, S; Livingston, J N

    1987-05-01

    Glucagon may play a role in the metabolic derangements of overt Type 2 (non-insulin-dependent) diabetes mellitus. We therefore have evaluated the early steps in glucagon action by investigating the hormone-sensitive adenylyl cyclase system in liver membranes from seven Type 2 diabetic patients with fasting hyperglycaemia and two-fold elevations in plasma glucagon. The comparison was made with seven control subjects matched for age, sex and body weight. Glucagon receptor binding was almost identical in the two groups. There were, however, marked alterations in the adenylyl cyclase activity in membranes from the diabetic patients. This activity was reduced by 35-50% when compared to control activity. Basal cyclase activity, as well as the activity after stimulation with glucagon or with agents (i.e., sodium fluoride and forskolin) that act beyond the glucagon receptor, was significantly decreased (p less than 0.05, p less than 0.001 respectively). In conclusion, uncontrolled Type 2 diabetes in associated with an over-all loss of responsiveness of the hormone-sensitive adenylyl cyclase in human liver, which apparently results from post-receptor alterations. This change may provide a mechanism for reducing the effect of hyperglycagonaemia in Type 2 diabetes mellitus. PMID:3038642

  9. Monitoring of human liver and kidney allograft tolerance: a tissue/histopathology perspective.

    PubMed

    Demetris, Anthony J; Lunz, John G; Randhawa, Parmjeet; Wu, Tong; Nalesnik, Michael; Thomson, Angus W

    2009-01-01

    Several factors acting together have recently enabled clinicians to seriously consider whether chronic immunosuppression is needed in all solid organ allograft recipients. This has prompted a dozen or so centers throughout the world to prospectively wean immunosuppression from conventionally treated liver allograft recipients. The goal is to lessen the impact of chronic immunosuppression and empirically identify occasional recipients who show operational tolerance, defined as gross phenotype of tolerance in the presence of an immune response and/or immune deficit that has little or no significant clinical impact. Rare operationally tolerant kidney allograft recipients have also been identified, usually by single case reports, but only a couple of prospective weaning trials in conventionally treated kidney allograft recipients have been attempted and reported. Pre- and postweaning allograft biopsy monitoring of recipients adds a critical dimension to these trials, not only for patient safety but also for determining whether events in the allografts can contribute to a mechanistic understanding of allograft acceptance. The following is based on a literature review and personal experience regarding the practical and scientific aspects of biopsy monitoring of potential or actual operationally tolerant human liver and kidney allograft recipients where the goal, intended or attained, was complete withdrawal of immunosuppression.

  10. Metabolism of lysergic acid diethylamide (LSD) to 2-oxo-3-hydroxy LSD (O-H-LSD) in human liver microsomes and cryopreserved human hepatocytes.

    PubMed

    Klette, K L; Anderson, C J; Poch, G K; Nimrod, A C; ElSohly, M A

    2000-10-01

    The metabolism of lysergic acid diethylamide (LSD) to 2-oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD) was investigated in liver microsomes and cyropreserved hepatocytes from humans. Previous studies have demonstrated that O-H-LSD is present in human urine at concentrations 16-43 times greater than LSD, the parent compound. Additionally, these studies have determined that O-H-LSD is not generated during the specimen extraction and analytical processes or due to parent compound degradation in aqueous urine samples. However, these studies have not been conclusive in demonstrating that O-H-LSD is uniquely produced during in vivo metabolism. Phase I drug metabolism was investigated by incubating human liver microsomes and cryopreserved human hepatocytes with LSD. The reaction was quenched at various time points, and the aliquots were extracted using liquid partitioning and analyzed by liquid chromatography-mass spectrometry. O-H-LSD was positively identified in all human liver microsomal and human hepatocyte fractions incubated with LSD. In addition, O-H-LSD was not detected in any microsomal or hepatocyte fraction not treated with LSD nor in LSD specimens devoid of microsomes or hepatocytes. This study provides definitive evidence that O-H-LSD is produced as a metabolic product following incubation of human liver microsomes and hepatocytes with LSD.

  11. Identification of potential biomarkers of hepatitis B-induced acute liver failure using hepatic cells derived from human skin precursors.

    PubMed

    Rodrigues, Robim M; Sachinidis, Agapios; De Boe, Veerle; Rogiers, Vera; Vanhaecke, Tamara; De Kock, Joery

    2015-09-01

    Besides their role in the elucidation of pathogenic processes of medical and pharmacological nature, biomarkers can also be used to document specific toxicological events. Hepatic cells generated from human skin-derived precursors (hSKP-HPC) were previously shown to be a promising in vitro tool for the evaluation of drug-induced hepatotoxicity. In this study, their capacity to identify potential liver-specific biomarkers at the gene expression level was investigated with particular emphasis on acute liver failure (ALF). To this end, a set of potential ALF-specific biomarkers was established using clinically relevant liver samples obtained from patients suffering from hepatitis B-associated ALF. Subsequently, this data was compared to data obtained from primary human hepatocyte cultures and hSKP-HPC, both exposed to the ALF-inducing reference compound acetaminophen. It was found that both in vitro systems revealed a set of molecules that was previously identified in the ALF liver samples. Yet, only a limited number of molecules was common between both in vitro systems and the ALF liver samples. Each of the in vitro systems could be used independently to identify potential toxicity biomarkers related to ALF. It seems therefore more appropriate to combine primary human hepatocyte cultures with complementary in vitro models to efficiently screen out potential hepatotoxic compounds.

  12. Selective In Vivo Targeting of Human Liver Tumors by Optimized AAV3 Vectors in a Murine Xenograft Model

    PubMed Central

    Wang, Yuan; Zhang, Yuanhui; Ejjigani, Anila; Yin, Zifei; Lu, Yuan; Wang, Lina; Wang, Meng; Li, Jun; Hu, Zhongbo; Aslanidi, George V.; Zhong, Li; Gao, Guangping

    2014-01-01

    Abstract Current challenges for recombinant adeno-associated virus (rAAV) vector–based cancer treatment include the low efficiency and the lack of specificity in vivo. rAAV serotype 3 (rAAV3) vectors have previously been shown to be ineffective in normal mouse tissues following systemic administration. In the present study, we report that rAAV3 vectors can efficiently target and transduce various human liver cancer cells in vivo. Elimination of specific surface-exposed serine and threonine residues on rAAV3 capsids results in further augmentation in the transduction efficiency of these vectors, without any change in the viral tropism and cellular receptor interactions. In addition, we have identified a potential chemotherapy drug, shikonin, as a multifunctional compound to inhibit liver tumor growth as well as to significantly enhance the efficacy of rAAV vector-based gene therapy in vivo. Furthermore, we also document that suppression of tumorigenesis in a human liver cancer xenograft model can be achieved through systemic administration of the optimized rAAV3 vectors carrying a therapeutic gene, and shikonin at a dose that does not lead to liver damage. Our research provides a novel means to achieve not only targeted delivery but also the potential for gene therapy of human liver cancer. PMID:25296041

  13. Selective in vivo targeting of human liver tumors by optimized AAV3 vectors in a murine xenograft model.

    PubMed

    Ling, Chen; Wang, Yuan; Zhang, Yuanhui; Ejjigani, Anila; Yin, Zifei; Lu, Yuan; Wang, Lina; Wang, Meng; Li, Jun; Hu, Zhongbo; Aslanidi, George V; Zhong, Li; Gao, Guangping; Srivastava, Arun; Ling, Changquan

    2014-12-01

    Current challenges for recombinant adeno-associated virus (rAAV) vector-based cancer treatment include the low efficiency and the lack of specificity in vivo. rAAV serotype 3 (rAAV3) vectors have previously been shown to be ineffective in normal mouse tissues following systemic administration. In the present study, we report that rAAV3 vectors can efficiently target and transduce various human liver cancer cells in vivo. Elimination of specific surface-exposed serine and threonine residues on rAAV3 capsids results in further augmentation in the transduction efficiency of these vectors, without any change in the viral tropism and cellular receptor interactions. In addition, we have identified a potential chemotherapy drug, shikonin, as a multifunctional compound to inhibit liver tumor growth as well as to significantly enhance the efficacy of rAAV vector-based gene therapy in vivo. Furthermore, we also document that suppression of tumorigenesis in a human liver cancer xenograft model can be achieved through systemic administration of the optimized rAAV3 vectors carrying a therapeutic gene, and shikonin at a dose that does not lead to liver damage. Our research provides a novel means to achieve not only targeted delivery but also the potential for gene therapy of human liver cancer.

  14. Comparative Proteomic Analysis of Human Liver Tissue and Isolated Hepatocytes with a Focus on Proteins Determining Drug Exposure.

    PubMed

    Vildhede, Anna; Wiśniewski, Jacek R; Norén, Agneta; Karlgren, Maria; Artursson, Per

    2015-08-01

    Freshly isolated human hepatocytes are considered the gold standard for in vitro studies of liver functions, including drug transport, metabolism, and toxicity. For accurate predictions of the in vivo outcome, the isolated hepatocytes should reflect the phenotype of their in vivo counterpart, i.e., hepatocytes in human liver tissue. Here, we quantified and compared the membrane proteomes of freshly isolated hepatocytes and human liver tissue using a label-free shotgun proteomics approach. A total of 5144 unique proteins were identified, spanning over 6 orders of magnitude in abundance. There was a good global correlation in protein abundance. However, the expression of many plasma membrane proteins was lower in the isolated hepatocytes than in the liver tissue. This included transport proteins that determine hepatocyte exposure to many drugs and endogenous compounds. Pathway analysis of the differentially expressed proteins confirmed that hepatocytes are exposed to oxidative stress during isolation and suggested that plasma membrane proteins were degraded via the protein ubiquitination pathway. Finally, using pitavastatin as an example, we show how protein quantifications can improve in vitro predictions of in vivo liver clearance. We tentatively conclude that our data set will be a useful resource for improved hepatocyte predictions of the in vivo outcome.

  15. Inhibition of fipronil and nonane metabolism in human liver microsomes and human cytochrome P450 isoforms by chlorpyrifos.

    PubMed

    Joo, Hyun; Choi, Kyoungju; Rose, Randy L; Hodgson, Ernest

    2007-01-01

    Previous studies have established that chlorpyrifos (CPS), fipronil, and nonane can all be metabolized by human liver microsomes (HLM) and a number of cytochrome P450 (CYP) isoforms. However, metabolic interactions between these three substrates have not been described. In this study the effect of either coincubation or preincubation of CPS with HLM or CYP isoforms with either fipronil or nonane as substrate was investigated. In both co- and preincubation experiments, CPS significantly inhibited the metabolism of fipronil or nonane by HLM although CPS inhibited the metabolism of fipronil more effectively than that of nonane. CPS significantly inhibited the metabolism of fipronil by CYP3A4 as well as the metabolism of nonane by CYP2B6. In both cases, preincubation with CPS caused greater inhibition than coincubation, suggesting that the inhibition is mechanism based.

  16. Norcocaine and N-hydroxynorcocaine formation in human liver microsomes: role of cytochrome P-450 3A4.

    PubMed

    LeDuc, B W; Sinclair, P R; Shuster, L; Sinclair, J F; Evans, J E; Greenblatt, D J

    1993-05-01

    Cocaine was metabolized to norcocaine by microsomes prepared from lymphoblastoid cells expressing transfected human P-450 3A4. The specific activities of norcocaine formation by microsomes prepared from three human liver samples correlated with the amount of P-450 3A immunoreactive protein detected by immunoblot. Triacetyloleandomycin, a specific inhibitor of P-450 3A isoforms, inhibited formation of norcocaine from cocaine, but not formation of N-hydroxynorcocaine from norcocaine. The chemical identity of the norcocaine and N-hydroxynorcocaine produced by human liver microsomes was established by combination of gas chromatography and mass spectrometry. Thus, human P-450 3A4 is a cocaine demethylase, and P-450 isoforms of the 3A family are responsible for the majority of norcocaine production by human hepatic microsomes.

  17. 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

  18. The Proteome of Human Liver Peroxisomes: Identification of Five New Peroxisomal Constituents by a Label-Free Quantitative Proteomics Survey

    PubMed Central

    Ofman, Rob; Bunse, Christian; Pawlas, Magdalena; Hayen, Heiko; Eisenacher, Martin; Stephan, Christian; Meyer, Helmut E.; Waterham, Hans R.; Erdmann, Ralf; Wanders, Ronald J.; Warscheid, Bettina

    2013-01-01

    The peroxisome is a key organelle of low abundance that fulfils various functions essential for human cell metabolism. Severe genetic diseases in humans are caused by defects in peroxisome biogenesis or deficiencies in the function of single peroxisomal proteins. To improve our knowledge of this important cellular structure, we studied for the first time human liver peroxisomes by quantitative proteomics. Peroxisomes were isolated by differential and Nycodenz density gradient centrifugation. A label-free quantitative study of 314 proteins across the density gradient was accomplished using high resolution mass spectrometry. By pairing statistical data evaluation, cDNA cloning and in vivo colocalization studies, we report the association of five new proteins with human liver peroxisomes. Among these, isochorismatase domain containing 1 protein points to the existence of a new metabolic pathway and hydroxysteroid dehydrogenase like 2 protein is likely involved in the transport or β-oxidation of fatty acids in human peroxisomes. The detection of alcohol dehydrogenase 1A suggests the presence of an alternative alcohol-oxidizing system in hepatic peroxisomes. In addition, lactate dehydrogenase A and malate dehydrogenase 1 partially associate with human liver peroxisomes and enzyme activity profiles support the idea that NAD+ becomes regenerated during fatty acid β-oxidation by alternative shuttling processes in human peroxisomes involving lactate dehydrogenase and/or malate dehydrogenase. Taken together, our data represent a valuable resource for future studies of peroxisome biochemistry that will advance research of human peroxisomes in health and disease. PMID:23460848

  19. Dataset from proteomic analysis of rat, mouse, and human liver microsomes and S9 fractions.

    PubMed

    Golizeh, Makan; Schneider, Christina; Ohlund, Leanne B; Sleno, Lekha

    2015-06-01

    Rat, mouse and human liver microsomes and S9 fractions were analyzed using an optimized method combining ion exchange fractionation of digested peptides, and ultra-high performance liquid chromatography (UHPLC) coupled to high resolution tandem mass spectrometry (HR-MS/MS). The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org) via the PRIDE partner repository (Vizcaíno et al., 2013 [1]) with the dataset identifiers PXD000717, PXD000720, PXD000721, PXD000731, PXD000733 and PXD000734. Data related to the peptides (trypsin digests only) were also uploaded to Peptide Atlas (Farrah et al., 2013 [2]) and are available with the dataset identifiers PASS00407, PASS00409, PASS00411, PASS00412, PASS00413 and PASS00414. The present dataset is associated with a research article published in EuPA Open Proteomics [3].

  20. Calcium channel antagonists and cyclosporine metabolism: in vitro studies with human liver microsomes.

    PubMed Central

    Tjia, J F; Back, D J; Breckenridge, A M

    1989-01-01

    The effects of four Ca2+ channel antagonists on the metabolism of cyclosporine (CsA) by human liver microsomes (n = 4) in vitro have been examined. Nicardipine produced marked inhibition of both M17 and M21 (IC50 = 7.0 microM) formation. In contrast nifedipine produced less than 20% inhibition of M17 and M21 even at the highest concentration examined (50 microM). Diltiazem data were comparable to those for nifedipine. Verapamil (50 microM) produced 30 and 28% inhibition of M17 and M21 formation, respectively. These findings give a basis to the increase in CsA blood concentrations seen in transplant patients who are also given nicardipine. PMID:2789931

  1. Molecular cloning and sequencing of zeta-crystallin/quinone reductase cDNA from human liver.

    PubMed

    Gonzalez, P; Rao, P V; Zigler, J S

    1993-03-31

    Zeta-crystallin is an enzyme-crystallin highly expressed in the lens of some hystricomorph rodents and camels. It has been shown to have a novel NADPH: quinone oxidoreductase activity and is present at enzymatic levels in a variety of tissues from various mammals. We report here the cDNA cloning of zeta-crystallin from a human liver library. One clone with the complete open reading frame was obtained. Ten nucleotides of the 5' and 796 of the 3' nontranslated regions are present in the clone including two possible polyadenylation signals. The deduced amino acid sequence is 328 residues long with a calculated molecular mass of 34910 daltons and isoelectric point of 8.73. It shows 84% identity with the guinea pig protein.

  2. The effect of enzyme inhibition on the metabolism and activation of tacrine by human liver microsomes.

    PubMed Central

    Spaldin, V; Madden, S; Pool, W F; Woolf, T F; Park, B K

    1994-01-01

    1. Tacrine (1,2,3,4-tetrahydro-9-aminoacridine-hydrochloride: THA) underwent metabolism in vitro by a panel (n = 12) of human liver microsomes genotyped for CYP2D6, in the presence of NADPH, to both protein-reactive and stable metabolites. 2. There was considerable variation in the extent of THA metabolism amongst human livers. Protein-reactive metabolite formation showed a 10-fold variation (0.6 +/- 0.1%-5.2 +/- 0.8% of incubated radioactivity mg-1 protein) whilst stable metabolites showed a 3-fold variation (24.3 +/- 1.7%-78.6 +/- 2.6% of incubated radioactivity). 3. Using cytochrome P450 isoform specific inhibitors CYP1A2 was identified as the major enzyme involved in all routes of THA metabolism. 4. There was a high correlation between aromatic and alicyclic hydroxylation (r = 0.92, P < 0.0001) consistent with these biotransformations being catalysed by the same enzymes. 5. Enoxacin (ENOX), cimetidine (CIM) and chloroquine (CQ) inhibited THA metabolism by a preferential decrease in the bioactivation to protein-reactive, and hence potentially toxic, species. The inhibitory potency of ENOX and CIM was increased significantly upon pre-incubation with microsomes and NADPH. 6. Covalent binding correlated with 7-OH-THA formation before (r = 0.792, P < 0.0001) and after (r = 0.73, P < 0.0001) inhibition by CIM, consistent with a two-step mechanism in the formation of protein-reactive metabolite(s) via a 7-OH intermediate. 7. The use of enzyme inhibitors may provide a useful tool for examining the relationship between the metabolism and toxicity of THA in vivo. PMID:7946932

  3. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies

    PubMed Central

    Giannios, Panagiotis; Toutouzas, Konstantinos G.; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M.; Zografos, George C.; Moutzouris, Konstantinos

    2016-01-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools. PMID:27297034

  4. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies.

    PubMed

    Giannios, Panagiotis; Toutouzas, Konstantinos G; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M; Zografos, George C; Moutzouris, Konstantinos

    2016-01-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools. PMID:27297034

  5. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies

    NASA Astrophysics Data System (ADS)

    Giannios, Panagiotis; Toutouzas, Konstantinos G.; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M.; Zografos, George C.; Moutzouris, Konstantinos

    2016-06-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools.

  6. Visible to near-infrared refractive properties of freshly-excised human-liver tissues: marking hepatic malignancies.

    PubMed

    Giannios, Panagiotis; Toutouzas, Konstantinos G; Matiatou, Maria; Stasinos, Konstantinos; Konstadoulakis, Manousos M; Zografos, George C; Moutzouris, Konstantinos

    2016-01-01

    The refractive index is an optical constant that plays a significant role in the description of light-matter interactions. When it comes to biological media, refraction is understudied despite recent advances in the field of bio-optics. In the present article, we report on the measurement of the refractive properties of freshly excised healthy and cancerous human liver samples, by use of a prism-coupling technique covering the visible and near-infrared spectral range. Novel data on the wavelength-dependent complex refractive index of human liver tissues are presented. The magnitude of the real and imaginary part of the refractive index is correlated with hepatic pathology. Notably, the real index contrast is pointed out as a marker of discrimination between normal liver tissue and hepatic metastases. In view of the current progress in optical biosensor technologies, our findings may be exploited for the development of novel surgical and endoscopic tools.

  7. Genetic factors affecting gene transcription and catalytic activity of UDP-glucuronosyltransferases in human liver.

    PubMed

    Liu, Wanqing; Ramírez, Jacqueline; Gamazon, Eric R; Mirkov, Snezana; Chen, Peixian; Wu, Kehua; Sun, Chang; Cox, Nancy J; Cook, Edwin; Das, Soma; Ratain, Mark J

    2014-10-15

    The aim of this study was to discover cis- and trans-acting factors significantly affecting mRNA expression and catalytic activity of human hepatic UDP-glucuronosyltransferases (UGTs). Transcription levels of five major hepatic UGT1A (UGT1A1, UGT1A3, UGT1A4, UGT1A6 and UGT1A9) and five UGT2B (UGT2B4, UGT2B7, UGT2B10, UGT2B15 and UGT2B17) genes were quantified in human liver tissue samples (n = 125) using real-time PCR. Glucuronidation activities of 14 substrates were measured in 47 livers. We genotyped 167 tagSNPs (single-nucleotide polymorphisms) in UGT1A (n = 43) and UGT2B (n = 124), as well as the known functional UGT1A1*28 and UGT2B17 CNV (copy number variation) polymorphisms. Transcription levels of 15 transcription factors (TFs) known to regulate these UGTs were quantified. We found that UGT expression and activity were highly variable among the livers (median and range of coefficient of variations: 135%, 74-217% and 52%, 39-105%, respectively). CAR, PXR and ESR1 were found to be the most important trans-regulators of UGT transcription (median and range of correlation coefficients: 46%, 6-58%; 47%, 9-58%; and 52%, 24-75%, respectively). Hepatic UGT activities were mainly determined by UGT gene transcription levels. Twenty-one polymorphisms were significantly (FDR-adjusted P < 0.05) associated with mRNA expression and/or activities of UGT1A1, UGT1A3 and UGT2B17. We found novel SNPs in the UGT2B17 CNV region accounting for variability in UGT2B17 gene transcription and testosterone glucuronidation rate, in addition to that attributable to the UGT2B17 CNV. Our study discovered novel pharmacogenetic markers and provided detailed insight into the genetic network regulating hepatic UGTs.

  8. Genetic factors affecting gene transcription and catalytic activity of UDP-glucuronosyltransferases in human liver.

    PubMed

    Liu, Wanqing; Ramírez, Jacqueline; Gamazon, Eric R; Mirkov, Snezana; Chen, Peixian; Wu, Kehua; Sun, Chang; Cox, Nancy J; Cook, Edwin; Das, Soma; Ratain, Mark J

    2014-10-15

    The aim of this study was to discover cis- and trans-acting factors significantly affecting mRNA expression and catalytic activity of human hepatic UDP-glucuronosyltransferases (UGTs). Transcription levels of five major hepatic UGT1A (UGT1A1, UGT1A3, UGT1A4, UGT1A6 and UGT1A9) and five UGT2B (UGT2B4, UGT2B7, UGT2B10, UGT2B15 and UGT2B17) genes were quantified in human liver tissue samples (n = 125) using real-time PCR. Glucuronidation activities of 14 substrates were measured in 47 livers. We genotyped 167 tagSNPs (single-nucleotide polymorphisms) in UGT1A (n = 43) and UGT2B (n = 124), as well as the known functional UGT1A1*28 and UGT2B17 CNV (copy number variation) polymorphisms. Transcription levels of 15 transcription factors (TFs) known to regulate these UGTs were quantified. We found that UGT expression and activity were highly variable among the livers (median and range of coefficient of variations: 135%, 74-217% and 52%, 39-105%, respectively). CAR, PXR and ESR1 were found to be the most important trans-regulators of UGT transcription (median and range of correlation coefficients: 46%, 6-58%; 47%, 9-58%; and 52%, 24-75%, respectively). Hepatic UGT activities were mainly determined by UGT gene transcription levels. Twenty-one polymorphisms were significantly (FDR-adjusted P < 0.05) associated with mRNA expression and/or activities of UGT1A1, UGT1A3 and UGT2B17. We found novel SNPs in the UGT2B17 CNV region accounting for variability in UGT2B17 gene transcription and testosterone glucuronidation rate, in addition to that attributable to the UGT2B17 CNV. Our study discovered novel pharmacogenetic markers and provided detailed insight into the genetic network regulating hepatic UGTs. PMID:24879639

  9. Liver metastases

    MedlinePlus

    Metastases to the liver; Metastatic liver cancer; Liver cancer - metastatic; Colorectal cancer - liver metastases; Colon cancer - liver metastases; Esophageal cancer - liver metastases; Lung cancer - liver metastases; Melanoma - liver metastases

  10. Evaluation of liver fluke recombinant cathepsin B-1 protease as a serodiagnostic antigen for human opisthorchiasis.

    PubMed

    Sripa, Jittiyawadee; Brindley, Paul J; Sripa, Banchob; Loukas, Alex; Kaewkes, Sasithorn; Laha, Thewarach

    2012-03-01

    A cathepsin B-like cysteine protease belonging to family C1 is abundantly expressed in the transcriptome and proteome of the carcinogenic liver fluke of humans, Opisthorchis viverrini. This enzyme is present in excretory/secretory (ES) products released by parasites cultured in vitro. This study evaluated the performance of recombinant O. viverrini cathepsin B1 (rOv-CB-1) as an antigen for immunodiagnosis of opisthorchiasis. The full length Ov-CB-1 cDNA was cloned and recombinant protein was produced in catalytically active form in Pichia pastoris. The recombinant Ov-CB-1 (rOv-CB-1) was affinity purified via nickel-NTA chromatography and tested in enzyme-linked immunosorbent assays (ELISA) with human sera from an opisthorchiasis endemic area. Sera from egg-positive O. viverrini infections produced a strong IgG antibody response to rOv-CB-1 both in ELISA and immunoblot analysis. The sensitivity and specificity of the ELISA test was 67% and 81%, respectively. These findings support the feasibility of using recombinant Ov-CB-1 in ELISA for the serodiagnosis of human opisthorchiasis. PMID:21704728

  11. Human Pluripotent Stem Cells: Myths and Future Realities for Liver Cell Therapy.

    PubMed

    Goldman, Orit; Gouon-Evans, Valerie

    2016-06-01

    The severe shortage of organ donors for treating patients with liver disease has prompted in vitro efforts to produce the main functional cells of the liver: hepatocyte-like cells (Hep cells). We consider the key challenges posed by various stem cell technologies and liver pathologies for developing clinically useful Hep cells. PMID:27257759

  12. Alcohol and aldehyde dehydrogenases: structures of the human liver enzymes, functional properties and evolutionary aspects.

    PubMed

    Jörnvall, H; Hempel, J; von Bahr-Lindström, H; Höög, J O; Vallee, B L

    1987-01-01

    polyol dehydrogenases are encountered. The two isozymes of human aldehyde dehydrogenase also exhibit considerable differences, with only 68% structural identity. The results show an early divergence into isozymes before the man/horse species radiation. Cys-302 is a functionally important residue and is located in one of the regions with conserved hydrophobic properties. Other regions with large differences in hydropathic properties may explain the absence of cross-hybridizing isozyme forms of human liver aldehyde dehydrogenase.

  13. Apoptosis in human hepatocellular carcinoma and in liver cell dysplasia is correlated with p53 protein immunoreactivity.

    PubMed Central

    Zhao, M; Zimmermann, A

    1997-01-01

    AIMS: To investigate the prevalence of apoptosis in human hepatocellular carcinomas (HCC) of different types and grades and in liver cell dysplasia, and to test whether the apoptotic rate is correlated with the p53 protein status. METHODS: 37 HCC and 66 six liver samples with liver cell dysplasia were analysed for apoptosis using in situ DNA end labelling (ISEL), and for p53 protein expression by immunohistochemistry. In HCCs, proliferative activity was quantitatively assessed using proliferating cell nuclear antigen labelling. RESULTS: The apoptotic index in HCC as based on ISEL ranged from 0.1 to 13.5 per 1000 cells analysed and was not related to type or grade. No nuclear staining was observed in multinuclear tumour cells. There was a significant correlation between the apoptotic rate and both the proliferative activity and p53 protein reactivity. In liver samples containing p53 protein positive liver cell dysplasia cells, there was a significantly higher apoptotic rate of these cells. CONCLUSIONS: Apoptosis is detectable in HCC, and is not related to type and grade. There is a highly significant positive correlation between the apoptotic rate in HCC and both the proliferative activity and p53 protein expression. A similar phenomenon occurs for putative cancer precursors. The findings support the role of p53 in regulating apoptosis in preneoplastic and neoplastic liver lesions. Images PMID:9215122

  14. Therapeutic Potential of HGF-Expressing Human Umbilical Cord Mesenchymal Stem Cells in Mice with Acute Liver Failure.

    PubMed

    Tang, Yunxia; Li, Qiongshu; Meng, Fanwei; Huang, Xingyu; Li, Chan; Zhou, Xin; Zeng, Xiaoping; He, Yixin; Liu, Jia; Hu, Xiang; Hu, Ji-Fan; Li, Tao

    2016-01-01

    Human umbilical cord-derived mesenchymal stem cells (UCMSCs) are particularly attractive cells for cellular and gene therapy in acute liver failure (ALF). However, the efficacy of this cell therapy in animal studies needs to be significantly improved before it can be translated into clinics. In this study, we investigated the therapeutic potential of UCMSCs that overexpress hepatocyte growth factor (HGF) in an acetaminophen-induced acute liver failure mouse model. We found that the HGF-UCMSC cell therapy protected animals from acute liver failure by reducing liver damage and prolonging animal survival. The therapeutic effect of HGF-UCMSCs was associated with the increment in serum glutathione (GSH) and hepatic enzymes that maintain redox homeostasis, including γ-glutamylcysteine synthetase (γ-GCS), superoxide dismutase (SOD), and catalase (CAT). Immunohistochemical staining confirmed that HGF-UCMSCs were mobilized to the injured areas of the liver. Additionally, HGF-UCMSCs modulated apoptosis by upregulating the antiapoptotic Bcl2 and downregulating proapoptotic genes, including Bax and TNFα. Taken together, these data suggest that ectopic expression of HGF in UCMSCs protects animals from acetaminophen-induced acute liver failure through antiapoptosis and antioxidation mechanisms. PMID:27057357

  15. Therapeutic Potential of HGF-Expressing Human Umbilical Cord Mesenchymal Stem Cells in Mice with Acute Liver Failure

    PubMed Central

    Tang, Yunxia; Li, Qiongshu; Meng, Fanwei; Huang, Xingyu; Li, Chan; Zhou, Xin; Zeng, Xiaoping; He, Yixin; Liu, Jia; Hu, Xiang; Hu, Ji-Fan; Li, Tao

    2016-01-01

    Human umbilical cord-derived mesenchymal stem cells (UCMSCs) are particularly attractive cells for cellular and gene therapy in acute liver failure (ALF). However, the efficacy of this cell therapy in animal studies needs to be significantly improved before it can be translated into clinics. In this study, we investigated the therapeutic potential of UCMSCs that overexpress hepatocyte growth factor (HGF) in an acetaminophen-induced acute liver failure mouse model. We found that the HGF-UCMSC cell therapy protected animals from acute liver failure by reducing liver damage and prolonging animal survival. The therapeutic effect of HGF-UCMSCs was associated with the increment in serum glutathione (GSH) and hepatic enzymes that maintain redox homeostasis, including γ-glutamylcysteine synthetase (γ-GCS), superoxide dismutase (SOD), and catalase (CAT). Immunohistochemical staining confirmed that HGF-UCMSCs were mobilized to the injured areas of the liver. Additionally, HGF-UCMSCs modulated apoptosis by upregulating the antiapoptotic Bcl2 and downregulating proapoptotic genes, including Bax and TNFα. Taken together, these data suggest that ectopic expression of HGF in UCMSCs protects animals from acetaminophen-induced acute liver failure through antiapoptosis and antioxidation mechanisms. PMID:27057357

  16. Polyamine and methionine adenosyltransferase 2A crosstalk in human colon and liver cancer

    SciTech Connect

    Tomasi, Maria Lauda; Ryoo, Minjung; Skay, Anna; Tomasi, Ivan; Giordano, Pasquale; Mato, José M.; Lu, Shelly C.

    2013-07-15

    Methionine adenosyltransferase (MAT) is an essential enzyme that is responsible for the biosynthesis of S-adenosylmethionine (SAMe), the principal methyl donor and precursor of polyamines. MAT1A is expressed in normal liver and MAT2A is expressed in all extrahepatic tissues. MAT2A expression is increased in human colon cancer and in colon cancer cells treated with mitogens, whereas silencing MAT2A resulted in apoptosis. The aim of the current work was to examine the mechanism responsible for MAT2A-dependent growth and apoptosis. We found that in RKO (human adenocarcinoma cell line) cells, MAT2A siRNA treatment lowered cellular SAMe and putrescine levels by 70–75%, increased apoptosis and inhibited growth. Putrescine supplementation blunted significantly MAT2A siRNA-induced apoptosis and growth suppression. Putrescine treatment (100 pmol/L) raised MAT2A mRNA level to 4.3-fold of control, increased the expression of c-Jun and c-Fos and binding to an AP-1 site in the human MAT2A promoter and the promoter activity. In human colon cancer specimens, the expression levels of MAT2A, ornithine decarboxylase (ODC), c-Jun and c-Fos are all elevated as compared to adjacent non-tumorous tissues. Overexpression of ODC in RKO cells also raised MAT2A mRNA level and MAT2A promoter activity. ODC and MAT2A are also overexpressed in liver cancer and consistently, similar MAT2A-ODC-putrescine interactions and effects on growth and apoptosis were observed in HepG2 cells. In conclusion, there is a crosstalk between polyamines and MAT2A. Increased MAT2A expression provides more SAMe for polyamines biosynthesis; increased polyamine (putrescine in this case) can activate MAT2A at the transcriptional level. This along with increased ODC expression in cancer all feed forward to further enhance the proliferative capacity of the cancer cell. -- Highlights: • MAT2A knockdown depletes putrescine and leads to apoptosis. • Putrescine attenuates MAT2A knockdown-induced apoptosis and growth

  17. Polyamine and methionine adenosyltransferase 2A crosstalk in human colon and liver cancer.

    PubMed

    Tomasi, Maria Lauda; Ryoo, Minjung; Skay, Anna; Tomasi, Ivan; Giordano, Pasquale; Mato, José M; Lu, Shelly C

    2013-07-15

    Methionine adenosyltransferase (MAT) is an essential enzyme that is responsible for the biosynthesis of S-adenosylmethionine (SAMe), the principal methyl donor and precursor of polyamines. MAT1A is expressed in normal liver and MAT2A is expressed in all extrahepatic tissues. MAT2A expression is increased in human colon cancer and in colon cancer cells treated with mitogens, whereas silencing MAT2A resulted in apoptosis. The aim of the current work was to examine the mechanism responsible for MAT2A-dependent growth and apoptosis. We found that in RKO (human adenocarcinoma cell line) cells, MAT2A siRNA treatment lowered cellular SAMe and putrescine levels by 70-75%, increased apoptosis and inhibited growth. Putrescine supplementation blunted significantly MAT2A siRNA-induced apoptosis and growth suppression. Putrescine treatment (100pmol/L) raised MAT2A mRNA level to 4.3-fold of control, increased the expression of c-Jun and c-Fos and binding to an AP-1 site in the human MAT2A promoter and the promoter activity. In human colon cancer specimens, the expression levels of MAT2A, ornithine decarboxylase (ODC), c-Jun and c-Fos are all elevated as compared to adjacent non-tumorous tissues. Overexpression of ODC in RKO cells also raised MAT2A mRNA level and MAT2A promoter activity. ODC and MAT2A are also overexpressed in liver cancer and consistently, similar MAT2A-ODC-putrescine interactions and effects on growth and apoptosis were observed in HepG2 cells. In conclusion, there is a crosstalk between polyamines and MAT2A. Increased MAT2A expression provides more SAMe for polyamines biosynthesis; increased polyamine (putrescine in this case) can activate MAT2A at the transcriptional level. This along with increased ODC expression in cancer all feed forward to further enhance the proliferative capacity of the cancer cell.

  18. Metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes.

    PubMed

    Li, Yan; Wu, Linan; Gu, Yuan; Si, Duanyun; Liu, Changxiao

    2014-06-01

    Aildenafil, 1-{[3-(6, 7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo [4, 3-d] primidin-5-yl)-4-ethoxyphenyl] sulfonyl}-cis-3, 5-dimethylpiperazine, a phosphodiesterase type V enzyme inhibitor (PDE5I), is under development for treatment of erectile dysfunction (ED). The purpose of this study was to elucidate metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes. Thirty-one phase I metabolites have been found by LTQ/Orbitrap hybrid mass spectrometry in rat urine, faeces, and bile after oral administration. Major biotransformation pathways of aildenafil included N-dealkylation of the piperazine ring, hydroxylation and dehydrogenation, aliphatic hydroxylation and loss of alkyl group of piperazine ring. Minor pathways involved hydroxylation on the phenyl ring, pyrazole N-demethylation, O-deethylation, loss of piperazine ring (cleavage of N-S bond) and dehydrogenation on the piperazine ring. Similar metabolic pathways of aildenafil were observed in the incubations of liver microsomes from mouse, rat, and dog as well as from human. The depletion rate of parent drug in mouse and rat liver microsomes was significantly different from that in human liver microsomes. The cytochrome P450 reaction phenotyping analysis was conducted using isozyme-specific inhibitors. The results indicated that CYP3A was the main isoenzyme involved in oxidative metabolism of aildenafil. Overall, these in vitro and in vivo findings should provide valuable information on possible metabolic behaviours of aildenafil in humans. PMID:24311535

  19. Metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes.

    PubMed

    Li, Yan; Wu, Linan; Gu, Yuan; Si, Duanyun; Liu, Changxiao

    2014-06-01

    Aildenafil, 1-{[3-(6, 7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo [4, 3-d] primidin-5-yl)-4-ethoxyphenyl] sulfonyl}-cis-3, 5-dimethylpiperazine, a phosphodiesterase type V enzyme inhibitor (PDE5I), is under development for treatment of erectile dysfunction (ED). The purpose of this study was to elucidate metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes. Thirty-one phase I metabolites have been found by LTQ/Orbitrap hybrid mass spectrometry in rat urine, faeces, and bile after oral administration. Major biotransformation pathways of aildenafil included N-dealkylation of the piperazine ring, hydroxylation and dehydrogenation, aliphatic hydroxylation and loss of alkyl group of piperazine ring. Minor pathways involved hydroxylation on the phenyl ring, pyrazole N-demethylation, O-deethylation, loss of piperazine ring (cleavage of N-S bond) and dehydrogenation on the piperazine ring. Similar metabolic pathways of aildenafil were observed in the incubations of liver microsomes from mouse, rat, and dog as well as from human. The depletion rate of parent drug in mouse and rat liver microsomes was significantly different from that in human liver microsomes. The cytochrome P450 reaction phenotyping analysis was conducted using isozyme-specific inhibitors. The results indicated that CYP3A was the main isoenzyme involved in oxidative metabolism of aildenafil. Overall, these in vitro and in vivo findings should provide valuable information on possible metabolic behaviours of aildenafil in humans.

  20. Prolyl Oligopeptidase Inhibition Attenuates Steatosis in the L02 Human Liver Cell Line

    PubMed Central

    Zhou, Da; Li, Bing-Hang; Wang, Jing; Ding, Yong-Nian; Dong, Yan; Chen, Yuan-Wen; Fan, Jian-Gao

    2016-01-01

    Background Prolyl oligopeptidase (POP) is a serine endopeptidase that is widely distributed in vivo, particularly in the liver. Significant changes in functional mitochondrial proteins involved with mitochondrial oxidoreductases/transporters and nucleic acid binding proteins were observed after POP inhibition in the liver, which suggested a role of POP in regulating liver energy metabolism. Steatosis in nonalcoholic fatty liver disease (NAFLD) is associated with disturbances in lipid and energy metabolism in hepatocytes. Here, we aimed to study the effect of POP on hepatocyte steatosis. Methods The human liver cell line L02 was used to investigate the biological effects of POP. An in vitro cell model of steatosis was successfully induced with oleic acid and palmitic acid. L02 cells were also subjected to S17092 (a POP inhibitor) at different concentrations for 24 or 48 h. Ac-SDKP levels and POP activity were measured to assess the rate of inhibition of POP by S17092. The POP gene and protein expression levels were detected using real-time PCR and Western blots, respectively. Oil red O staining was performed and the triglyceride levels in the L02 cells were also measured. Cell proliferation and apoptosis were detected using CCK-8 and flow cytometry, respectively. The expression of genes involved in lipid metabolism was detected using real-time PCR. The effects of POP inhibition on LC3B II were detected by Western blot. Results Compared with the control, the POP mRNA levels increased by approximately 30%, and the POP protein levels increased by almost 60% in the steatotic L02 cells. After S17092 (0.026~130 μM) incubation for 24 or 48 h, cell proliferation was significantly decreased in the free fatty acid (FFA)-treated cells at 26–130 μM; however, S17092 did not affect the proliferation of L02 cells after 24 h of incubation with S17092 at 0.026–65 μM without FFA treatment. S17092 treatment (13 and 26 μM) also elicited no significant effect on apoptosis in

  1. Human urine and plasma concentrations of bisphenol A extrapolated from pharmacokinetics established in in vivo experiments with chimeric mice with humanized liver and semi-physiological pharmacokinetic modeling.

    PubMed

    Miyaguchi, Takamori; Suemizu, Hiroshi; Shimizu, Makiko; Shida, Satomi; Nishiyama, Sayako; Takano, Ryohji; Murayama, Norie; Yamazaki, Hiroshi

    2015-06-01

    The aim of this study was to extrapolate to humans the pharmacokinetics of estrogen analog bisphenol A determined in chimeric mice transplanted with human hepatocytes. Higher plasma concentrations and urinary excretions of bisphenol A glucuronide (a primary metabolite of bisphenol A) were observed in chimeric mice than in control mice after oral administrations, presumably because of enterohepatic circulation of bisphenol A glucuronide in control mice. Bisphenol A glucuronidation was faster in mouse liver microsomes than in human liver microsomes. These findings suggest a predominantly urinary excretion route of bisphenol A glucuronide in chimeric mice with humanized liver. Reported human plasma and urine data for bisphenol A glucuronide after single oral administration of 0.1mg/kg bisphenol A were reasonably estimated using the current semi-physiological pharmacokinetic model extrapolated from humanized mice data using algometric scaling. The reported geometric mean urinary bisphenol A concentration in the U.S. population of 2.64μg/L underwent reverse dosimetry modeling with the current human semi-physiological pharmacokinetic model. This yielded an estimated exposure of 0.024μg/kg/day, which was less than the daily tolerable intake of bisphenol A (50μg/kg/day), implying little risk to humans. Semi-physiological pharmacokinetic modeling will likely prove useful for determining the species-dependent toxicological risk of bisphenol A.

  2. Quantitative ATP synthesis in human liver measured by localized 31P spectroscopy using the magnetization transfer experiment.

    PubMed

    Schmid, A I; Chmelík, M; Szendroedi, J; Krssák, M; Brehm, A; Moser, E; Roden, M

    2008-06-01

    The liver plays a central role in intermediate metabolism. Accumulation of liver fat (steatosis) predisposes to various liver diseases. Steatosis and abnormal muscle energy metabolism are found in insulin-resistant and type-2 diabetic states. To examine hepatic energy metabolism, we measured hepatocellular lipid content, using proton MRS, and rates of hepatic ATP synthesis in vivo, using the 31P magnetization transfer experiment. A suitable localization scheme was developed and applied to the measurements of longitudinal relaxation times (T1) in six healthy volunteers and the ATP-synthesis experiment in nine healthy volunteers. Liver 31P spectra were modelled and quantified successfully using a time domain fit and the AMARES (advanced method for accurate, robust and efficient spectral fitting of MRS data with use of prior knowledge) algorithm describing the essential components of the dataset. The measured T1 relaxation times are comparable to values reported previously at lower field strengths. All nine subjects in whom saturation transfer was measured had low hepatocellular lipid content (1.5 +/- 0.2% MR signal; mean +/- SEM). The exchange rate constant (k) obtained was 0.30 +/- 0.02 s(-1), and the rate of ATP synthesis was 29.5 +/- 1.8 mM/min. The measured rate of ATP synthesis is about three times higher than in human skeletal muscle and human visual cortex, but only about half of that measured in perfused rat liver. In conclusion, 31P MRS at 3 T provides sufficient sensitivity to detect magnetization transfer effects and can therefore be used to assess ATP synthesis in human liver.

  3. The influence of tissue procurement procedures on RNA integrity, gene expression, and morphology in porcine and human liver tissue.

    PubMed

    Kap, Marcel; Sieuwerts, Anieta M; Kubista, Mikael; Oomen, Monique; Arshad, Shazia; Riegman, Peter

    2015-06-01

    The advent of molecular characterization of tissues has brought an increasing emphasis on the quality of biospecimens, starting with the tissue procurement process. RNA levels are particularly affected by factors in the collection process, but the influence of different pre-analytical factors is not well understood. Here we present the influence of tissue specimen size, as well as the transport and freezing protocols, on RNA quality. Large, medium, and smaller porcine liver samples were stored either dry, on moist gauze, or in salt solution for various times, and then frozen in either liquid nitrogen or in pre-cooled isopentane. Large and small human liver samples were frozen in pre-cooled isopentane either immediately or after one hour at room temperature. The small samples were stored dry, on moist gauze, or in salt solution. RNA was isolated and RIN values were measured. The RNA for six standard reference genes from human liver was analyzed by RT-qPCR, and tissue morphology was assessed for artifacts of freezing. Experiments using porcine liver samples showed that RNA derived from smaller samples was more degraded after one hour of cold ischemia, and that cooled transport is preferable. Human liver samples showed significant RNA degradation after 1 h of cold ischemia, which was more pronounced in smaller samples. RNA integrity was not significantly influenced by the transport or freezing method, but changes in gene expression were observed in samples either transported on gauze or in salt solution. Based on observations in liver samples, smaller samples are more subject to gene expression variability introduced by post-excision sample handling than are larger samples. Small biopsies should be transported on ice and snap frozen as soon as possible after acquisition from the patient. PMID:26035010

  4. In vitro studies on the oxidative metabolism of 20(s)-ginsenoside Rh2 in human, monkey, dog, rat, and mouse liver microsomes, and human liver s9.

    PubMed

    Li, Liang; Chen, Xiaoyan; Zhou, Jialan; Zhong, Dafang

    2012-10-01

    20(S)-Ginsenoside Rh2 (Rh2)-containing products are widely used in Asia, Europe, and North America. However, extremely limited metabolism information greatly impedes the complete understanding of its clinical safety and effectiveness. The present study aims to systematically investigate the oxidative metabolism of Rh2 using a complementary set of in vitro models. Twenty-five oxidative metabolites were found using liquid chromatography-electrospray ionization ion-trap mass spectrometry. Six metabolites and a metabolic intermediate were synthesized. The metabolites were structurally identified as 26-hydroxy Rh2 (M1-1), (20S,24S)-epoxydammarane-12,25-diol-3-β-d-glucopyranoside (M1-3), (20S,24R)-epoxydammarane-12,25-diol-3-β-d-glucopyranoside (M1-5), 26,27-dihydroxy Rh2 (M3-6), (20S,24S)-epoxydammarane-12,25,26-triol-3-β-d-glucopyranoside (M3-10), (20S,24R)-epoxydammarane-12,25,26-triol-3-β-d-glucopyranoside (M3-11), and 26-aldehyde Rh2 on the basis of detailed mass spectrometry and nuclear magnetic resonance data analysis. Double-bond epoxidation followed by rearrangement and vinyl-methyl group hydroxylation represent the initial metabolic pathways generating monooxygenated metabolites M1-1 to M1-5. Further sequential metabolites (M2-M5) from the dehydrogenation and/or oxygenation of M1 were also detected. CYP3A4 was the predominant enzyme involved in the oxidative metabolism of Rh2, whereas alcohol dehydrogenase and aldehyde dehydrogenase mainly catalyzed the metabolic conversion of alcohol to the corresponding carboxylic acid. No significant differences were observed in the phase I metabolite profiles of Rh2 among the five species tested. Reactive epoxide metabolite formation in both humans and animals was evident. However, GSH conjugate M6 was detected only in cynomolgus monkey liver microsomal incubations. In conclusion, Rh2 is a good substrate for CYP3A4 and could undergo extensive oxidative metabolism under the catalysis of CYP3A4. PMID:22829543

  5. Molecular cloning of cDNAs of human liver and placenta NADH-cytochrome b/sub 5/ reductase

    SciTech Connect

    Yubisui, T.; Naitoh, Y.; Zenno, S.; Tamura, M.; Takeshita, M.; Sakaki, Y.

    1987-06-01

    A cDNA coding for human liver NADH-cytochrome b/sub 5/ reductase was cloned from a human liver cDNA library constructed in phage lambdagt11. The library was screened by using an affinity-purified rabbit antibody against NADH-cytochrome b/sub 5/ reductase of human erythrocytes. A cDNA about 1.3 kilobase pairs long was isolated. By using the cDNA as a probe, another cDNA (pb/sub 5/R141) of 1817 base pairs was isolated that hybridized with a synthetic oligonucleotide encoding Pro-Asp-Ile-Lys-Tyr-Pro, derived from the amino acid sequence at the amino-terminal region of the enzyme from human erythrocytes. Furthermore, by using the pb/sub 5/R141 as a probe, cDNA clones having more 5' sequence were isolated from a human placenta cDNA library. The amino acid sequences deduced from the nucleotide sequences of these cDNA clones overlapped each other and consisted of a sequence that completely coincides with that of human erythrocytes and a sequence of 19 amino acid residues extended at the amino-terminal side. The latter sequence closely resembles that of the membrane-binding domain of steer liver microsomal enzyme

  6. Troglitazone thiol adduct formation in human liver microsomes: enzyme kinetics and reaction phenotyping.

    PubMed

    Gan, Jinping; Qu, Qinling; He, Bing; Shyu, Wen C; Rodrigues, A David; He, Kan

    2008-08-01

    Troglitazone (TGZ) induced hepatotoxicity has been linked to cytochrome P450 (CYP)-catalyzed reactive metabolite formation. Therefore, the kinetics and CYP specificity of reactive metabolite formation were studied using dansyl glutathione (dGSH) as a trapping agent after incubation of TGZ with human liver microsomes (HLM) and recombinant human CYP proteins. CYP2C8 exhibited the highest rate of TGZ adduct (TGZ-dGS) formation, followed by CYP3A4, CYP3A5, and CYP2C19. The involvement of CYP2C8 and CYP3A4 was confirmed with CYP form-selective chemical inhibitors. The impact of TGZ concentration on the rate of TGZ-dGS formation was also evaluated. In this instance, two distinctly different profiles were observed with recombinant CYP3A4 and CYP2C8. It is concluded that both CYP3A4/5 and CYP2C8 play a major role in the formation of TGZ adduct in HLM. However, the contribution of these CYPs varies depending on their relative expression and the concentration of TGZ. PMID:19356091

  7. Inhibition of Cytochrome P450 by Propolis in Human Liver Microsomes

    PubMed Central

    Ryu, Chang Seon; Oh, Soo Jin; Oh, Jung Min; Lee, Ji-Yoon; Lee, Sang Yoon; Chae, Jung-woo; Kwon, Kwang-il; Kim, Sang Kyum

    2016-01-01

    Although propolis is one of the most popular functional foods for human health, there have been no comprehensive studies of herb-drug interactions through cytochrome P450 (CYP) inhibition. The purpose of this study was to determine the inhibitory effects of propolis on the activities of CYP1A2, 2A6, 2B6, 2C9, 2C19, 2D6, 2E1 and 3A4 using pooled human liver microsomes (HLMs). Propolis inhibited CYP1A2, CYP2E1 and CYP2C19 with an IC50 value of 6.9, 16.8, and 43.1 μg/mL, respectively, whereas CYP2A6, 2B6, 2C9, 2D6, and 3A4 were unaffected. Based on half-maximal inhibitory concentration shifts between microsomes incubated with and without nicotinamide adenine dinucleotide phosphate, propolis-induced CYP1A2, CYP2C19, and CYP2E1 inhibition was metabolism-independent. To evaluate the interaction potential between propolis and therapeutic drugs, the effects of propolis on metabolism of duloxetine, a serotonin-norepinephrine reuptake inhibitor, were determined in HLMs. CYP1A2 and CYP2D6 are involved in hydroxylation of duloxetine to 4-hydroxy duloxetine, the major metabolite, which was decreased following propolis addition in HLMs. These results raise the possibility of interactions between propolis and therapeutic drugs metabolized by CYP1A2. PMID:27437087

  8. 3'-azido-3'-deoxythymidine drug interactions. Screening for inhibitors in human liver microsomes.

    PubMed

    Rajaonarison, J F; Lacarelle, B; Catalin, J; Placidi, M; Rahmani, R

    1992-01-01

    Zidovudine is a widely used antiretroviral drug active against human immunodeficiency virus. The drug interactions of this compound, which are primarily eliminated as a glucuronide, have not yet been extensively studied. Because zidovudine is frequently combined with other drugs, complete knowledge of interactions is essential to optimize AIDS therapy. We therefore screened the effect of 55 molecules, representative of 20 different therapeutic classes, on 3'-azido-3'-deoxythymidine (AZT) glucuronidation by human liver microsomes. We demonstrate that many drugs caused more than 15% inhibition of AZT glucuronidation in vitro, whereas major antibiotics (ceftazidine, isoniazid, aminoglycosides, macrolides, and sulfamides), antivirals (2',3'-dideoxycytidine, 2',3'-dideoxyinosine, and acyclovir), flucytosine, metronidazole, acetaminophen, and ranitidine had no effect. For compounds that appeared to inhibit AZT glucuronidation, extrapolation to the clinical situation must take into account both the in vitro apparent Ki values and the usual expected plasma level for the coadministered drug. By considering these parameters, this work indicates that clinically relevant inhibition of AZT glucuronidation may be observed with the following drugs: cefoperazone, penicillin G, amoxicilin, piperacillin, chloramphenicol, vancomycin, miconazole, rifampicin, phenobarbital, carbamazepine, phenytoin, valproic acid, quinidine, phenylbutazone, ketoprofen, probenecid, and propofol. Complementary clinical and pharmacokinetic studies should be performed to validate these assumptions.

  9. Endogenous and xenobiotic metabolite profiling of liver extracts from SCID and chimeric humanized mice following repeated oral administration of troglitazone.

    PubMed

    Barnes, Alan J; Baker, David R; Hobby, Kirsten; Ashton, Simon; Michopoulos, Filippos; Spagou, Konstantina; Loftus, Neil J; Wilson, Ian D

    2014-01-01

    1. Metabonomic analysis, via a combination of untargeted and targeted liquid chromatography-mass spectrometry (LC-MS) and untargeted (1)H NMR spectroscopy-based metabolite profiling, was performed on aqueous (AQ) and organic liver extracts from control (SCID) and chimeric humanized (PXB) mice dosed with troglitazone at 0, 300 and 600 mg/kg/day for seven days. 2. LC-MS analysis of AQ liver extracts showed a more "human-like" profile for troglitazone metabolites for PXB, compared with SCID, mice. 3. LC-MS detected differences in endogenous metabolites, particularly lipid species in dosed mice, including elevated triacylglycerols and 1-alkyl,2-acylglycerophosphates as well as lowered diacylglycerophosphocholines and 1-alkyl,2-acylglycerophosphocholines for PXB compared with SCID mouse liver extracts. Following drug administration changes in the relative proportions of the ions for various unsaturated fatty acids were observed for both types of mouse, some of which were specific to PXB or SCID mice. 4.  (1)H NMR spectroscopy revealed that AQ PXB mouse liver extracts had elevated amounts of inosine, fumarate, creatine, aspartate, trimethylamine N-oxide, glycerophosphocholine, phosphocholine, choline, glutamine, glutamate, acetate, alanine and lactate relative to SCID mice and decreased histidine, glycogen, α- and β-glucose, taurine, and glutathione. Increased uracil and tyrosine concentrations were detected for PXB mice on troglitazone administration. 5. Metabonomic profiling thus showed clear differences between humanized and SCID mice, including after administration of troglitazone.

  10. Reduction of 3-keto-5 beta-cholanoic acid to lithocholic and isolithocholic acids by human liver cytosol in vitro.

    PubMed

    Amuro, Y; Yamade, W; Maebo, A; Hada, T; Higashino, K

    1985-10-23

    The formation of lithocholic and isolithocholic acids from 3-keto-5 beta-cholanoic acid by human liver cytosol was examined in vitro. Liver cytosol was incubated at various pH levels with 3-keto-5 beta-cholanoic acid in a phosphate buffer containing NADPH or NADH; the products formed were analyzed by gas chromatography. Results showed that human liver cytosol reduced 3-keto-5 beta-cholanoic acid to lithocholic acid at a pH level of 7.0 or above and to isolithocholic acid at a pH level of 6.0 or below when NADPH was used as a coenzyme, and it was reduced to isolithocholic acid only when NADH was used. Furthermore, two peaks for the reducing enzymes could be clearly found by column chromatography of Affi-Gel Blue. These results indicate that human liver cytosol contains two enzymes acting on reduction of 3-keto-5 beta-cholanoic acid to lithocholic and isolithocholic acids, which are dependent on the pH level and the use of NADPH or NADH in vitro. Since the 3 beta-dehydrogenation was inhibited by the addition of pyrazole, an alcohol dehydrogenase inhibitor or ethanol, and the major peak of 3 beta-hydroxysteroid dehydrogenase coincided with the peak of alcohol dehydrogenase on Affi-Gel Blue chromatography, at least some of the cytosolic 3 beta-hydroxysteroid dehydrogenase seemed to be identical to or to have characteristics similar to alcohol dehydrogenase. PMID:2932163

  11. Simian virus 40 large tumor antigen-immortalized normal human liver epithelial cells express hepatocyte characteristics and metabolize chemical carcinogens.

    PubMed Central

    Pfeifer, A M; Cole, K E; Smoot, D T; Weston, A; Groopman, J D; Shields, P G; Vignaud, J M; Juillerat, M; Lipsky, M M; Trump, B F

    1993-01-01

    Normal human liver tissue and cultured human hepatocytes are valuable models to study xenobiotic metabolism and toxicity, but they only have a limited in vitro life-span and are not readily available. This report describes the establishment of replicative cultures of human adult liver epithelial cells in serum-free medium. The longevity of three of these cultures, derived from different donors, was extended by introduction of the simian virus 40 large T antigen gene. Two cell lines, THLE-2 and -3, established with a recombinant simian virus 40 large T antigen virus have undergone > 100 population doublings, are nontumorigenic when injected into athymic nude mice, have near-diploid karyotypes, and do not express alpha-fetoprotein. The cells express cytokeratin 18 and albumin in early passage, whereas higher-passage cells in logarithmic-phase growth also express cytokeratin 19. THLE-2 and -3 cells metabolize benzo[a]pyrene, N-nitrosodimethylamine, and aflatoxin B1 to their ultimate carcinogenic metabolites that adduct DNA, which indicates functional cytochrome P450 pathways. Other enzymes involved in metabolism of chemical carcinogens, such as epoxide hydrolase, NADPH cytochrome P450 reductase, superoxide dismutase, catalase, glutathione S-transferases, and glutathione peroxidase are also retained by THLE cells. Thus, these immortalized human liver cells constitute an in vitro model for pharmacotoxicological studies and for the investigation of etiology and pathogenesis of human hepatocellular carcinoma. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:7685115

  12. Absolute Quantification of Human Liver Phosphorus-Containing Metabolites In Vivo Using an Inhomogeneous Spoiling Magnetic Field Gradient

    PubMed Central

    Bashir, Adil; Gropler, Robert; Ackerman, Joseph

    2015-01-01

    Purpose Absolute concentrations of high-energy phosphorus (31P) metabolites in liver provide more important insight into physiologic status of liver disease compared to resonance integral ratios. A simple method for measuring absolute concentrations of 31P metabolites in human liver is described. The approach uses surface spoiling inhomogeneous magnetic field gradient to select signal from liver tissue. The technique avoids issues caused by respiratory motion, chemical shift dispersion associated with linear magnetic field gradients, and increased tissue heat deposition due to radiofrequency absorption, especially at high field strength. Methods A method to localize signal from liver was demonstrated using superficial and highly non-uniform magnetic field gradients, which eliminate signal(s) from surface tissue(s) located between the liver and RF coil. A double standard method was implemented to determine absolute 31P metabolite concentrations in vivo. 8 healthy individuals were examined in a 3 T MR scanner. Results Concentrations of metabolites measured in eight healthy individuals are: γ-adenosine triphosphate (ATP) = 2.44 ± 0.21 (mean ± sd) mmol/l of wet tissue volume, α-ATP = 3.2 ± 0.63 mmol/l, β-ATP = 2.98 ± 0.45 mmol/l, inorganic phosphates (Pi) = 1.87 ± 0.25 mmol/l, phosphodiesters (PDE) = 10.62 ± 2.20 mmol/l and phosphomonoesters (PME) = 2.12 ± 0.51 mmol/l. All are in good agreement with literature values. Conclusions The technique offers robust and fast means to localize signal from liver tissue, allows absolute metabolite concentration determination, and avoids problems associated with constant field gradient (linear field variation) localization methods. PMID:26633549

  13. Prediction of liver fibrosis in human immunodeficiency virus/hepatitis C virus coinfected patients by simple non‐invasive indexes

    PubMed Central

    Macías, J; Girón‐González, J A; González‐Serrano, M; Merino, D; Cano, P; Mira, J A; Arizcorreta‐Yarza, A; Ruíz‐Morales, J; Lomas‐Cabeza, J M; García‐García, J A; Corzo, J E; Pineda, J A

    2006-01-01

    Background Liver biopsy is an invasive technique with associated major complications. There is no information on the validity of five non‐invasive indexes based on routinely available parameters, estimated and validated in hepatitis C virus (HCV) monoinfected patients, in human immunodeficiency virus (HIV)/HCV coinfected patients. Aim To validate these predictive models of liver fibrosis in HIV/HCV coinfected patients. Patients A total of 357 (90%) of 398 patients from five hospitals were investigated, who underwent liver biopsy and who had complete data to validate all of the models considered. Methods The predictive accuracy of the indexes was tested by measuring areas under the receiver operating characteristic curves. Diagnostic accuracy was calculated by estimating sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values. Results The models performed better when liver biopsies ⩾15 mm were used as reference. In this setting, the Forns and Wai indexes, models aimed at discriminating significant fibrosis, showed PPV of 94% and 87%, respectively. Using these models, 27–34% of patients could benefit from exclusion of liver biopsy. If both models were applied sequentially, 41% of liver biopsies could be spared. The indexes aimed at predicting cirrhosis achieved NPV of up to 100%. However, they showed very low PPV. Conclusions The diagnostic accuracy of these models was lower in HIV/HCV coinfected patients than in the validation studies performed in HCV monoinfected patients. However, simple fibrosis tests may render liver biopsy unnecessary in deciding anti‐HCV treatment in over one third of patients with HIV infection and chronic hepatitis C. PMID:16118349

  14. A biochemical comparison of normal human liver and hepatocellular carcinoma ferritins.

    PubMed

    Bullock, S; Bomford, A; Williams, R

    1980-03-01

    1. The iron contents, gel migration rates and isoelectric-focusing patterns of normal liver and hepatocellular carcinoma ferritins from the same patients were compared. 2. Sucrose-density-gradient centrifugation showed that the number of iron atoms per ferritin molecule was decreased to approximately half in carcinoma tissue when compared with normal liver. 3. On electrophoresis, hepatocellular carcinoma ferritin migrates faster and is therefore more negatively charged than normal liver ferritin, thus refuting the general view that the more negatively charged a ferritin molecule the greater its iron content. 4. Comparison of tumour and normal liver ferritin subunit compositions on acid/urea/polyacrylamide gels showed hepatocellular carcinoma ferritin to contain an additional, more negatively charged, subunit to normal liver ferritin. 5. Isoelectric focusing showed that hepatocellular carcinoma tissue contains isoferritins with isoelectric points intermediate between the ranges of normal liver and normal heart isoferritins. PMID:6248028

  15. Kinetic characteristics of norcocaine N-hydroxylation in mouse and human liver microsomes: involvement of CYP enzymes.

    PubMed

    Pellinen, P; Kulmala, L; Konttila, J; Auriola, S; Pasanen, M; Juvonen, R

    2000-11-01

    The first step in the oxidative metabolism of cocaine is N-demethylation to norcocaine, which is further N-hydroxylated to more toxic N-hydroxynorcocaine. In this study we examined the kinetics of norcocaine N-hydroxylation mediated by cytochrome P450 (CYP) in mouse and human liver microsomes. N-hydroxynorcocaine was identified by analytical HPLC-MS after incubation of norcocaine with mouse liver microsomes in the presence of NADPH. In mouse liver microsomes, there was no apparent difference in Km values for norcocaine N-hydroxylation between male and female microsomes, while the Vmax rate was approximately two times higher in female than in male microsomes (34+/-10 v. 16+/-4 pmol/min per mg protein). The Km value for norcocaine N-hydroxylation in human liver microsomes was approximately three times higher than that observed in comparable incubations using mouse liver microsomes, whereas the Vmax rate was ten times lower. Both cocaine and norcocaine induced type I difference spectra upon interaction with CYP in mouse liver microsomes. In contrast, in human microsomes both type I and type II spectra were recorded. In the 0.01 to 1 mM concentration range, cocaine and norcocaine inhibited mouse microsomal testosterone 6alpha-, 7alpha- and 16alpha-hydroxylation reactions by 20% to 30%. Testosterone 6beta- and 15alpha-hydroxylations were blocked by 60% and 50%, respectively, by 1 mM norcocaine, while only 40% inhibition was obtained with 1 mM cocaine. Coumarin 7-hydroxylation and pentoxyresorufin O-deethylation were inhibited by 50% by 1 and 0.4 mM norcocaine, respectively. In contrast, 10 and 2 mM cocaine, respectively, were needed to obtain the same degrees of inhibition. In human liver microsomes, 1 mM norcocaine and cocaine blocked testosterone 6beta-hydroxylase by 60% and 40%, respectively. Coumarin 7-hydroxylation was inhibited by only 30% by norcocaine (5.4 mM) and cocaine (10 mM). Norcocaine N-hydroxylation in mouse and human liver microsomes was blocked by 30

  16. Transcriptional regulation of the human Liver X Receptor α gene by Hepatocyte Nuclear Factor 4α.

    PubMed

    Theofilatos, Dimitris; Anestis, Aristomenis; Hashimoto, Koshi; Kardassis, Dimitris

    2016-01-15

    Liver X Receptors (LXRs) are sterol-activated transcription factors that play major roles in cellular cholesterol homeostasis, HDL biogenesis and reverse cholesterol transport. The aim of the present study was to investigate the mechanisms that control the expression of the human LXRα gene in hepatic cells. A series of reporter plasmids containing consecutive 5' deletions of the hLXRα promoter upstream of the luciferase gene were constructed and the activity of each construct was measured in HepG2 cells. This analysis showed that the activity of the human LXRα promoter was significantly reduced by deleting the -111 to -42 region suggesting the presence of positive regulatory elements in this short proximal fragment. Bioinformatics data including motif search and ChIP-Seq revealed the presence of a potential binding motif for Hepatocyte Nuclear Factor 4 α (HNF-4α) in this area. Overexpression of HNF-4α in HEK 293T cells increased the expression of all LXRα promoter constructs except -42/+384. In line, silencing the expression of endogenous HNF-4α in HepG2 cells was associated with reduced LXRα protein levels and reduced activity of the -111/+384 LXRα promoter but not of the -42/+384 promoter. Using ChiP assays in HepG2 cells combined with DNAP assays we mapped the novel HNF-4α specific binding motif (H4-SBM) in the -50 to -40 region of the human LXRα promoter. A triple mutation in this H4-SBM abolished HNF-4α binding and reduced the activity of the promoter to 65% relative to the wild type. Furthermore, the mutant promoter could not be transactivated by HNF-4α. In conclusion, our data indicate that HNF-4α may have a wider role in cell and plasma cholesterol homeostasis by controlling the expression of LXRα in hepatic cells. PMID:26692490

  17. In vitro metabolism of nobiletin, a polymethoxy-flavonoid, by human liver microsomes and cytochrome P450.

    PubMed

    Koga, Nobuyuki; Ohta, Chiho; Kato, Yoshihisa; Haraguchi, Koichi; Endo, Tetsuya; Ogawa, Kazunori; Ohta, Hideaki; Yano, Masamichi

    2011-11-01

    Cytochrome P450 enzymes (CYPs) in the liver metabolize drugs prior to excretion, with different enzymes acting at different molecular motifs. At present, the human CYPs responsible for the metabolism of the flavonoid, nobiletin (NBL), are unidentified. We investigated which enzymes were involved using human liver microsomes and 12 cDNA-expressed human CYPs. Human liver microsomes metabolized NBL to three mono-demethylated metabolites (4'-OH-, 7-OH- and 6-OH-NBL) with a relative ratio of 1:4.1:0.5, respectively, by aerobic incubation with nicotinamide adenine dinucleotide phosphate (NADPH). Of 12 human CYPs, CYP1A1, CYP1A2 and CYP1B1 showed high activity for the formation of 4'-OH-NBL. CYP3A4 catalyzed the formation of 7-OH-NBL with the highest activity and of 6-OH-NBL with lower activity. CYP3A5 also catalyzed the formation of both metabolites but considerably more slowly than CYP3A4. In contrast, seven CYPs (CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6 and CYP2E1) were inactive for NBL. Both ketoconazole and troleandomycin (CYP3A inhibitors) almost completely inhibited the formation of 7-OH- and 6-OH-NBL. Similarly, α-naphthoflavone (CYP1A1 inhibitor) and furafylline (CYP1A2 inhibitor) significantly decreased the formation of 4'-OH-NBL. These results suggest that CYP1A2 and CYP3A4 are the key enzymes in human liver mediating the oxidative demethylation of NBL in the B-ring and A-ring, respectively.

  18. Single-walled carbon nanohorn (SWNH) aggregates inhibited proliferation of human liver cell lines and promoted apoptosis, especially for hepatoma cell lines

    PubMed Central

    Zhang, Jinqian; Sun, Qiang; Bo, Jian; Huang, Rui; Zhang, Mengran; Xia, Zhenglin; Ju, Lili; Xiang, Guoan

    2014-01-01

    Single-walled carbon nanohorns (SWNHs) may be useful as carriers for anticancer drugs due to their particular structure. However, the interactions between the material itself and cancerous or normal cells have seldom been studied. To address this problem, the effects of raw SWNH material on the biological functions of human liver cell lines were studied. Our results showed that unmodified SWNHs inhibited mitotic entry, growth, and proliferation of human liver cell lines and promoted their apoptosis, especially in hepatoma cell lines. Individual spherical SWNH particles were found inside the nuclei of human hepatoma HepG2 cells and the lysosomes of normal human liver L02 cells, implying that SWNH particles could penetrate into human liver cells_and the different interacted mechanisms on human normal cell lines compared to hepatoma cell lines. Further research on the mechanisms and application in treatment of hepatocellular carcinoma with SWNHs is needed. PMID:24523586

  19. Iodine 123-17-iodoheptadecanoic acid for metabolic liver studies in humans

    SciTech Connect

    Hoeck, A.S.; Spohr, G.; Schmitz, M.; Notohamiprodjo, G.; Porschen, R.; Vyska, K.; Freundlieb, C.; Shreeve, W.W.; Feinendegen, L.E.

    1986-10-01

    (17-/sup 123/I)-Iodoheptadecanoic acid ((/sup 123/I)HA) was used for dynamic planar scintigraphy of the liver in normal individuals (control I), in patients without liver disease but with elevated serum cholesterol and/or triglycerides (control II), and in patient groups with alcohol-induced fatty liver (PG I), fatty liver not due to alcohol (PG II), alcohol-induced liver cirrhosis (PG III), or liver cirrhosis of the posthepatitic type (PG IV). Tracer uptake and elimination time were assayed in different liver regions; mean elimination time was expressed for total liver. In control I, tracer uptake was homogeneous, and mean elimination time was 20.7 +/- 5.3 min without significant local variations. In control II, tracer uptake was reduced but homogeneous and mean elimination time was 59.4 +/- 35.8 min with some local variations. In PG I, uptake was reduced and inhomogeneous and elimination time was the same as in control I, irrespective of cholesterol and triglyceride values. In PG II, uptake was the same as in PG I but mean elimination time was 48 +/- 8.1 min with some local variations. In PG III, uptake was extremely reduced and spotty and elimination time correlated with the severity of disease from 19 to 881 min in different liver regions.

  20. Genome-wide analysis of DNA methylation and gene expression patterns in purified, uncultured human liver cells and activated hepatic stellate cells

    PubMed Central

    Reiner, Andrew H.; Coll, Mar; Verhulst, Stefaan; Mannaerts, Inge; Øie, Cristina I.; Smedsrød, Bård; Najimi, Mustapha; Sokal, Etienne; Luttun, Aernout; Sancho-Bru, Pau; Collas, Philippe; van Grunsven, Leo A.

    2015-01-01

    Background & Aims Liver fibrogenesis – scarring of the liver that can lead to cirrhosis and liver cancer – is characterized by hepatocyte impairment, capillarization of liver sinusoidal endothelial cells (LSECs) and hepatic stellate cell (HSC) activation. To date, the molecular determinants of a healthy human liver cell phenotype remain largely uncharacterized. Here, we assess the transcriptome and the genome-wide promoter methylome specific for purified, non-cultured human hepatocytes, LSECs and HSCs, and investigate the nature of epigenetic changes accompanying transcriptional changes associated with activation of HSCs. Material and methods Gene expression profile and promoter methylome of purified, uncultured human liver cells and culture-activated HSCs were respectively determined using Affymetrix HG-U219 genechips and by methylated DNA immunoprecipitation coupled to promoter array hybridization. Histone modification patterns were assessed at the single-gene level by chromatin immunoprecipitation and quantitative PCR. Results We unveil a DNA-methylation-based epigenetic relationship between hepatocytes, LSECs and HSCs despite their distinct ontogeny. We show that liver cell type-specific DNA methylation targets early developmental and differentiation-associated functions. Integrative analysis of promoter methylome and transcriptome reveals partial concordance between DNA methylation and transcriptional changes associated with human HSC activation. Further, we identify concordant histone methylation and acetylation changes in the promoter and putative novel enhancer elements of genes involved in liver fibrosis. Conclusions Our study provides the first epigenetic blueprint of three distinct freshly isolated, human hepatic cell types and of epigenetic changes elicited upon HSC activation. PMID:26353929

  1. Human liver sinusoidal endothelial cells respond to interaction with Entamoeba histolytica by changes in morphology, integrin signalling and cell death.

    PubMed

    Faust, Daniela M; Marquay Markiewicz, Jacques; Danckaert, Anne; Soubigou, Guillaume; Guillen, Nancy

    2011-07-01

    Invasive infection with Entamoeba histolytica causes intestinal and hepatic amoebiasis. In liver, parasites cross the endothelial barrier before abscess formation in the parenchyma. We focussed on amoebae interactions with human hepatic endothelial cells, the latter potentially playing a dual role in the infection process: as a barrier and as modulators of host defence responses. We characterized early responses of a human liver sinusoidal endothelial cell line to virulent and virulence-attenuated E. histolytica. Within the first minutes human cells start to retract, enter into apoptosis and die. In the presence of virulent amoebae, expression of genes related to cell cycle, cell death and integrin-mediated adhesion signalling was modulated, and actin fibre, focal adhesion kinase and paxillin localizations changed. Effects of inhibitors and amoeba strains not expressing pathogenic factors amoebapore A and cysteine protease A5 indicated that cell death and cytoskeleton disorganization depend upon parasite adhesion and amoebic cysteine proteinase activities. The data establish a relation between cytotoxic effects of E. histolytica and altered human target cell adhesion and suggest that interference with adhesion signalling triggers endothelial cell retraction and death. Understanding the roles of integrin signalling in endothelial cells will provide clues to unravel host-pathogen interactions during amoebic liver infection. PMID:21624031

  2. Comparative bioactivation of the novel anti-tuberculosis agent PA-824 in Mycobacteria and a subcellular fraction of human liver

    PubMed Central

    Dogra, M; Palmer, BD; Bashiri, G; Tingle, MD; Shinde, SS; Anderson, RF; O'Toole, R; Baker, EN; Denny, WA; Helsby, NA

    2011-01-01

    BACKGROUND AND PURPOSE PA-824 is a 2-nitroimidazooxazine prodrug currently in Phase II clinical trial for tuberculosis therapy. It is bioactivated by a deazaflavin (F420)-dependent nitroreductase (Ddn) isolated from Mycobacterium tuberculosis to form a des-nitro metabolite. This releases toxic reactive nitrogen species which may be responsible for its anti-mycobacterial activity. There are no published reports of mammalian enzymes bioactivating this prodrug. We have investigated the metabolism of PA-824 following incubation with a subcellular fraction of human liver, in comparison with purified Ddn, M. tuberculosis and Mycobacterium smegmatis. EXPERIMENTAL APPROACH PA-824 (250 µM) was incubated with the 9000×g supernatant (S9) of human liver homogenates, purified Ddn, M. tuberculosis and M. smegmatis for metabolite identification by liquid chromatography mass spectrometry analysis. KEY RESULTS PA-824 was metabolized to seven products by Ddn and M. tuberculosis, with the major metabolite being the des-nitro product. Six of these products, but not the des-nitro metabolite, were also detected in M. smegmatis. In contrast, only four of these metabolites were observed in human liver S9; M3, a reduction product previously proposed as an intermediate in the Ddn-catalyzed des-nitrification and radiolytic reduction of PA-824; two unidentified metabolites, M1 and M4, which were products of M3; and a haem-catalyzed product of imidazole ring hydration (M2). CONCLUSIONS AND IMPLICATIONS PA-824 was metabolized by des-nitrification in Ddn and M. tuberculosis, but this does not occur in human liver S9 and M. smegmatis. Thus, PA-824 was selectively bioactivated in M. tuberculosis and there was no evidence for ‘cross-activation’ by human enzymes. PMID:20955364

  3. In vitro metabolism of phenoxypropoxybiguanide analogues in human liver microsomes to potent antimalarial dihydrotriazines.

    PubMed

    Shearer, Todd W; Kozar, Michael P; O'Neil, Michael T; Smith, Philip L; Schiehser, Guy A; Jacobus, David P; Diaz, Damaris S; Yang, Young-Sun; Milhous, Wilbur K; Skillman, Donald R

    2005-04-21

    Phenoxypropoxybiguanides, such as 1 (PS-15), are prodrugs analogous to the relationship of proguanil and its active metabolite cycloguanil. Unlike cycloguanil, however, 1a (WR99210), the active metabolite of 1, has retained in vitro potency against newly emerging antifolate-resistant malaria parasites. Unfortunately, manufacturing processes and gastrointestinal intolerance have prevented the clinical development of 1. In vitro antimalarial activity and in vitro metabolism studies have been performed on newly synthesized phenoxypropoxybiguanide analogues. All of the active dihydrotriazine metabolites exhibited potent antimalarial activity with in vitro IC(50) values less than 0.04 ng/mL. In vitro metabolism studies in human liver microsomes identified the production of not only the active dihydrotriazine metabolite, but also a desalkylation on the carbonyl chain, and multiple hydroxylated metabolites. The V(max) for production of the active metabolites ranged from 10.8 to 27.7 pmol/min/mg protein with the K(m) ranging from 44.8 to 221 microM. The results of these studies will be used to guide the selection of a lead candidate.

  4. Cellular effects of metolachlor exposure on human liver (HepG2) cells.

    PubMed

    Hartnett, Sean; Musah, Sadiatu; Dhanwada, Kavita R

    2013-01-01

    Metolachlor is one of the most commonly used herbicides in the United States. Protein synthesis is inhibited when roots and shoots of susceptible plants absorb this synthetic herbicide. While quite effective in killing weeds, several studies have shown that exposure to metolachlor results in decreased cell proliferation, growth and reproductive ability of non-target organisms. However, the mode of metolachlor action in non-target organisms has not yet been elucidated. The current study assessed effects of metolachlor exposure on immortalized human liver (HepG2) cells. Results from cell proliferation assays showed that a 72-h exposure to 50 parts per billion (ppb) metolachlor significantly inhibited growth of these cells compared to untreated controls while a decrease in the cell division rate required exposure to 500 ppb metolachlor for 48 h. Flow cytometry analysis of cell cycle distribution revealed that 500 ppb metolachlor treatment resulted in fewer HepG2 cells in G2/M phase after 72 h. Real-time PCR analysis showed a significant decrease in the abundance of the cyclin A transcripts after 12h in cells exposed to 300 ppb metolachlor. These results suggest metolachlor may affect progression through the S phase of the cell cycle and entrance into the G2 phase. PMID:23084262

  5. Irreversible electroporation and apoptosis in human liver cancer cells induced by nanosecond electric pulses.

    PubMed

    Xiao, Deyou; Yao, Chenguo; Liu, Huan; Li, Chengxiang; Cheng, Jie; Guo, Fei; Tang, Liling

    2013-10-01

    The goal of this study was to assess the effect of nanosecond electric pulses on HepG2 human liver cancer cells. Electric pulses with a high strength of 10 kV/cm, duration of 500 ns and frequency of 1 Hz were applied to the cells. After delivery of electric pulses, apoptosis, intracellular calcium ion concentrations, transmembrane mitochondrial potentials, electropermeabilization and recovery from electropermeabilization in cells were investigated. The results showed that electric pulse treatment for 20 s and more could trigger apoptosis in cells. Real-time observation indicated an immediate increase in intracellular calcium ion concentration and a dramatic decrease in mitochondrial membrane potential in cells responding to electric pulses. In subsequent experiments, propidium iodide uptake in cells emerged after exposure to electric pulses, indicating electropermeabilization of the cell membrane. Furthermore, recovery from electropermeabilization was not observed even 4 h after the stimulation, demonstrating that irreversible electropermeabilization was induced by electric pulses. In conclusion, electric pulses with a high strength and nanosecond duration can damage cancer cells, accompanied by a series of intracellular changes, providing strong evidence for the application of electric pulses in cancer treatment. PMID:23740887

  6. Inhibition of Acute in vivo Human Immunodeficiency Virus Infection by Human Interleukin 10 Treatment of SCID Mice Implanted with Human Fetal Thymus and Liver

    NASA Astrophysics Data System (ADS)

    Kollmann, Tobias R.; Pettoello-Mantovani, Massimo; Katopodis, Nikos F.; Hachamovitch, Moshe; Rubinstein, Arye; Kim, Ana; Goldstein, Harris

    1996-04-01

    To improve the usefulness of in vivo models for the investigation of the pathophysiology of human immunodeficiency virus (HIV) infection, we modified the construction of SCID mice implanted with human fetal thymus and liver (thy/liv-SCID-hu mice) so that the peripheral blood of the mice contained significant numbers of human monocytes and T cells. After inoculation with HIV-159, a primary patient isolate capable of infecting monocytes and T cells, the modified thy/liv-SCID-hu mice developed disseminated HIV infection that was associated with plasma viremia. The development of plasma viremia and HIV infection in thy/liv-SCID-hu mice inoculated with HIV-159 was inhibited by acute treatment with human interleukin (IL) 10 but not with human IL-12. The human peripheral blood mononuclear cells in these modified thy/liv-SCID-hu mice were responsive in vivo to treatment with exogenous cytokines. Human interferon γ expression in the circulating human peripheral blood mononuclear cells was induced by treatment with IL-12 and inhibited by treatment with IL-10. Thus, these modified thy/liv-SCID-hu mice should prove to be a valuable in vivo model for examining the role of immunomodulatory therapy in modifying HIV infection. Furthermore, our demonstration of the in vivo inhibitory effect of IL-10 on acute HIV infection suggests that further studies may be warranted to evaluate whether there is a role for IL-10 therapy in preventing HIV infection in individuals soon after exposure to HIV such as for children born to HIV-infected mothers.

  7. Inhibition of acute in vivo human immunodeficiency virus infection by human interleukin 10 treatment of SCID mice implanted with human fetal thymus and liver.

    PubMed Central

    Kollmann, T R; Pettoello-Mantovani, M; Katopodis, N F; Hachamovitch, M; Rubinstein, A; Kim, A; Goldstein, H

    1996-01-01

    To improve the usefulness of in vivo mode for the investigation of the pathophysiology of human immunodeficiency virus (HIV) infection, we modified the construction of SCID mice implanted with human fetal thymus and liver (thy/liv-SCID-hu mice) so that the peripheral blood of the mice contained significant numbers of human monocytes and T cells. After inoculation with HIV-1(59), a primary patient isolate capable of infecting monocytes and T cells, the modified thy/liv-SCID-hu mice developed disseminated HIV infection that was associated with plasma viremia. The development of plasma viremia and HIV infection in thy/liv-SCID-hu mice inoculated with HIV-1(59) was inhibited by acute treatment with human interleukin (IL) 10 but not with human IL-12. The human peripheral blood mononuclear cells in these modified thy/liv-SCID-hu mice were responsive to in vivo treatment with exogenous cytokines. Human interferon gamma expression in the circulating human peripheral blood mononuclear cells was induced by treatment with IL-12 and inhibited by treatment with IL-10. Thus, these modified thy/liv-SCID-hu mice should prove to be a valuable in vivo model for examining the role of immunomodulatory therapy in modifying HIV infection. Furthermore, our demonstration of the vivo inhibitory effect of IL-10 on acute HIV infection suggests that further studies may be warranted to evaluate whether there is a role for IL-10 therapy in preventing HIV infection in individuals soon after exposure to HIV such as for children born to HIV-infected mothers. Images Fig. 2 Fig. 3 PMID:8610180

  8. Formation of the Thiol Conjugates and Active Metabolite of Clopidogrel by Human Liver Microsomes

    PubMed Central

    Lau, Wei C.; Hollenberg, Paul F.

    2012-01-01

    We reported previously the formation of a glutathionyl conjugate of the active metabolite (AM) of clopidogrel and the covalent modification of a cysteinyl residue of human cytochrome P450 2B6 in a reconstituted system (Mol Pharmacol 80:839–847, 2011). In this work, we extended our studies of the metabolism of clopidogrel to human liver microsomes in the presence of four reductants, namely, GSH, l-Cys, N-acetyl-l-cysteine (NAC), and ascorbic acid. Our results demonstrated that formation of the AM was greatly affected by the reductant used and the relative amounts of the AM formed were increased in the following order: NAC (17%) < l-Cys (53%) < ascorbic acid (61%) < GSH (100%). AM-thiol conjugates were observed in the presence of NAC, l-Cys, and GSH. In the case of GSH, the formation of both the AM and the glutathionyl conjugate was dependent on the GSH concentrations, with similar Km values of ∼0.5 mM, which indicates that formation of the thiol conjugates constitutes an integral part of the bioactivation processes for clopidogrel. It was observed that the AM was slowly converted to the thiol conjugate, with a half-life of ∼10 h. Addition of dithiothreitol to the reaction mixture reversed the conversion, which resulted in a decrease in AM-thiol conjugate levels and a concomitant increase in AM levels, whereas addition of NAC led to the formation of AM-NAC and a concomitant decrease in AM-GSH levels. These results not only confirm that the AM is formed through oxidative opening of the thiolactone ring but also suggest the existence of an equilibrium between the AM, the thiol conjugates, and the reductants. These factors may affect the effective concentrations of the AM in vivo. PMID:22584220

  9. Genome-wide landscape of liver X receptor chromatin binding and gene regulation in human macrophages

    PubMed Central

    2012-01-01

    Background The liver X receptors (LXRs) are oxysterol sensing nuclear receptors with multiple effects on metabolism and immune cells. However, the complete genome-wide cistrome of LXR in cells of human origin has not yet been provided. Results We performed ChIP-seq in phorbol myristate acetate-differentiated THP-1 cells (macrophage-type) after stimulation with the potent synthetic LXR ligand T0901317 (T09). Microarray gene expression analysis was performed in the same cellular model. We identified 1357 genome-wide LXR locations (FDR < 1%), of which 526 were observed after T09 treatment. De novo analysis of LXR binding sequences identified a DR4-type element as the major motif. On mRNA level T09 up-regulated 1258 genes and repressed 455 genes. Our results show that LXR actions are focused on 112 genomic regions that contain up to 11 T09 target genes per region under the control of highly stringent LXR binding sites with individual constellations for each region. We could confirm that LXR controls lipid metabolism and transport and observed a strong association with apoptosis-related functions. Conclusions This first report on genome-wide binding of LXR in a human cell line provides new insights into the transcriptional network of LXR and its target genes with their link to physiological processes, such as apoptosis. The gene expression microarray and sequence data have been submitted collectively to the NCBI Gene Expression Omnibus http://www.ncbi.nlm.nih.gov/geo under accession number GSE28319. PMID:22292898

  10. In vitro glucuronidation of five rhubarb anthraquinones by intestinal and liver microsomes from humans and rats.

    PubMed

    Wu, Wenjin; Hu, Nan; Zhang, Qingwen; Li, Yaping; Li, Peng; Yan, Ru; Wang, Yitao

    2014-08-01

    Anthraquinones naturally distribute in many plants including rhubarb and have widespread applications throughout industry and medicine. Recent studies provided new insights in potential applications of these traditional laxative constituents. Glucuronidation was the main metabolic pathway of rhubarb anthraquinones in vivo. This study examined the activity and regioselectivity of glucuronidation of rhubarb anthraquinones (aloe-emodin, emodin, chrysophanol, physcion, rhein) in liver and intestinal microsomes from rats and humans, by comparing with the core structure danthron. All anthraquinones formed mono-glucuronides and, except for rhein, the conjugation sites of the main metabolites were unambiguously identified. Two minor glucuronides of emodin were first reported together with the dominant emodin-3-O-β-D-glucuronide. The substitution on the anthraquinone ring was crucial to the activity and regioselectivity of glucuronidation. In general, the activity was decreased greatly with a β-COOH (rhein), while enhanced dramatically with a β-OH (emodin). Glucuronidation showed an absolute preference towards β-OH, followed by α-OH and β-alcoholic OH. The glucuronidation activity and regioselectivity also varied slightly with organs and species. All glucuronides of aloe-emodin, emodin, chrysophanol and physcion were formed by multiple human UGT isoforms with 1A9 being the most prominent in most cases. The UGT2B subfamily (2B7 and 2B15) only showed high activity towards a β-OH. In conclusion, the substitution at the anthraquinone ring was crucial to the rate and preference of glucuronidation. The high glucuronidation activity of UGT1A9 towards anthraquinones highlighted potential drug interactions.

  11. Bone marrow stem cells contribute to alcohol liver fibrosis in humans.

    PubMed

    Dalakas, Evangelos; Newsome, Philip N; Boyle, Shelagh; Brown, Rachael; Pryde, Anne; McCall, Shonna; Hayes, Peter C; Bickmore, Wendy A; Harrison, David J; Plevris, John N

    2010-09-01

    Bone marrow-derived stem cell (BMSC) contribution to liver repair varies considerably and recent evidence suggests these cells may contribute to liver fibrosis. We investigated the mobilization and hepatic recruitment of bone marrow (BM) stem cells in patients with alcohol liver injury and their contribution to parenchymal/non-parenchymal liver cell lineages. Liver biopsies from alcoholic hepatitis (AH) patients and male patients, who received a female liver transplant and developed AH, were analyzed for BM stem cell content by fluorescence in situ hybridization and immunostaining. Y chromosome analysis was performed, along with co-staining for hepatocyte, biliary, myofibroblast, and Ki-67 markers. Blood CD34(+) levels were quantified in AH patients by flow cytometry. AH patients had increased CD34(+) cell counts in liver tissue (1.834% +/- 0.605%; P < 0.05) and in blood (0.195% +/- 0.063%; P < 0.05) as compared with matched controls (0.299% + 0.208% and 0.067% +/- 0.01%). A proportion of hepatic myofibroblasts were BM-derived (7.9%-26.8%) as deemed by the co-localization of Y chromosome/alpha-smooth muscle actin (alpha-SMA) staining. In the cross-sex liver grafts with AH, 5.025% of the myofibroblasts were co-staining for CD34, suggesting that a population of CD34(+) cells were contributing to the hepatic myofibroblast population. There was no evidence of BM contribution to hepatocyte or biliary cell differentiation, nor evidence of increased hepatocyte regeneration. Alcohol liver injury mobilizes CD34(+) stem cells into the circulation and recruits them into the liver. These BMSCs contribute to the hepatic myofibroblast population but not to parenchymal lineages and do not promote hepatocyte repair.

  12. Evidence of in vitro glucuronidation and enzymatic transformation of paralytic shellfish toxins by healthy human liver microsomes fraction.

    PubMed

    García, Carlos; Rodriguez-Navarro, Alberto; Díaz, Juan Carlos; Torres, Rafael; Lagos, Néstor

    2009-02-01

    Paralytic Shellfish Toxins (PST) are endemic components found in filter bivalves in Southern Chile. Post-mortems analysis of fluid and tissue samples has shown biotransformation of PST in humans. The Gonyautoxin 3 (GTX3) and Gonyautoxin 2 (GTX2) are the major PST components in the toxin profile found in Chilean shellfish extracts, being as much as 65% of the total content of PST in filter bivalves. Therefore, they are the major accountable components of the human intoxication by shellfish consumption. The aim of this study is to show in vitro glucuronidation and biotransformation of GTX3 and GTX2 when they are incubated with microsomal fraction isolated from healthy human livers. Microsomes fractions isolated from human livers were incubated with GTX3 and GTX2 purified from contaminated mussels. After different incubation times, incubated samples were extracted and analyzed by HPLC with fluorescent on line detection and HPLC-MS analysis. The results revealed that GTX3 and GTX2, only when they were incubated with microsomal fraction and appropriated cofactors, showed to be enzymatic transformed in vitro. The glucuronidation of GTX3 and GTX2 followed typical Michaelis-Menten kinetics, resulting in apparent kinetic parameters of Km=39.4+/-0.24 microM and Vmax=6.0x10(-3) pmol/min/mg protein. In addition, the microsomes fraction also oxidized GTX3 and GTX2 into Gonyautoxin 4 (GTX 4) and Gonyautoxin 1 (GTX 1) resulting in 0.339x10(-3) pmol/min/mg protein. In conclusion, this study reports oxidation and glucuronidation of GTX3 and GTX2 when they are incubated with human liver microsomal fraction. The metabolism occurs via a glucuronidation reaction, the basis first step of biotransformation in human liver. Also it is showed that GTX4 and GTX1 came by biotransformation from GTX3 and GTX2 in humans. This data confirm human biotransformation found in human post-mortem fluid and tissue samples described previously. This data is the first evidence of in vitro glucuronidation

  13. Expression of platelet-derived growth factor and its receptors in normal human liver and during active hepatic fibrogenesis.

    PubMed Central

    Pinzani, M.; Milani, S.; Herbst, H.; DeFranco, R.; Grappone, C.; Gentilini, A.; Caligiuri, A.; Pellegrini, G.; Ngo, D. V.; Romanelli, R. G.; Gentilini, P.

    1996-01-01

    Expression of platelet-derived growth factor (PDGF) and its receptor (R) subunits was evaluated in normal human liver and in cirrhotic liver tissue by in situ hybridization and immunohistochemistry. In normal liver, PDGF and PDGF-R subunit expression was limited to a few mesenchymal cells of the portal tract stroma and vessels. In cirrhotic liver, PDGF-A and -B chain mRNA expression was markedly increased and was co-distributed with immunoreactivity for PDGF-AA and -BB in infiltrating inflammatory cells and along vascular structures within fibrous septa. These aspects were paralleled by a marked overexpression of PDGF-R alpha- and beta-subunit mRNAs and of the relative immunoreactivities in a wide range of mesenchymal cells in fibrous septa and in perisinusoidal alpha-smooth-muscle-actin-positive cells. In general expression and distribution of PDGF-R subunits appeared to be related to the activation of different mesenchymal cell types involved in the fibroproliferative process. Therefore, we evaluated the expression of PDGF-R subunits in liver tissue specimens with increasing degrees of necroinflammatory activity. The results of this additional study confirmed that expression of PDGF-R subunits is highly correlated with the severity of histological lesions and collagen deposition. Our results, providing evidence for a functional involvement of PDGF/PDGF-R in liver fibrogenesis, greatly support the results of previous in vitro studies and direct attention toward pharmacological strategies able to affect the series of signaling events arising from the autophosphorylation of PDGF-R subunits. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8774134

  14. Deregulation of energy metabolism promotes antifibrotic effects in human hepatic stellate cells and prevents liver fibrosis in a mouse model.

    PubMed

    Karthikeyan, Swathi; Potter, James J; Geschwind, Jean-Francois; Sur, Surojit; Hamilton, James P; Vogelstein, Bert; Kinzler, Kenneth W; Mezey, Esteban; Ganapathy-Kanniappan, Shanmugasundaram

    2016-01-15

    Liver fibrosis and cirrhosis result from uncontrolled secretion and accumulation of extracellular matrix (ECM) proteins by hepatic stellate cells (HSCs) that are activated by liver injury and inflammation. Despite the progress in understanding the biology liver fibrogenesis and the identification of potential targets for treating fibrosis, development of an effective therapy remains elusive. Since an uninterrupted supply of intracellular energy is critical for the activated-HSCs to maintain constant synthesis and secretion of ECM, we hypothesized that interfering with energy metabolism could affect ECM secretion. Here we report that a sublethal dose of the energy blocker, 3-bromopyruvate (3-BrPA) facilitates phenotypic alteration of activated LX-2 (a human hepatic stellate cell line), into a less-active form. This treatment-dependent reversal of activated-LX2 cells was evidenced by a reduction in α-smooth muscle actin (α-SMA) and collagen secretion, and an increase in activity of matrix metalloproteases. Mechanistically, 3-BrPA-dependent antifibrotic effects involved down-regulation of the mitochondrial metabolic enzyme, ATP5E, and up-regulation of glycolysis, as evident by elevated levels of lactate dehydrogenase, lactate production and its transporter, MCT4. Finally, the antifibrotic effects of 3-BrPA were validated in vivo in a mouse model of carbon tetrachloride-induced liver fibrosis. Results from histopathology & histochemical staining for collagen and α-SMA substantiated that 3-BrPA promotes antifibrotic effects in vivo. Taken together, our data indicate that sublethal, metronomic treatment with 3-BrPA blocks the progression of liver fibrosis suggesting its potential as a novel therapeutic for treating liver fibrosis.

  15. Comprehensive microRNA profiling in acetaminophen toxicity identifies novel circulating biomarkers for human liver and kidney injury.

    PubMed

    Vliegenthart, A D B; Shaffer, J M; Clarke, J I; Peeters, L E J; Caporali, A; Bateman, D N; Wood, D M; Dargan, P I; Craig, D G; Moore, J K; Thompson, A I; Henderson, N C; Webb, D J; Sharkey, J; Antoine, D J; Park, B K; Bailey, M A; Lader, E; Simpson, K J; Dear, J W

    2015-01-01

    Our objective was to identify microRNA (miRNA) biomarkers of drug-induced liver and kidney injury by profiling the circulating miRNome in patients with acetaminophen overdose. Plasma miRNAs were quantified in age- and sex-matched overdose patients with (N = 27) and without (N = 27) organ injury (APAP-TOX and APAP-no TOX, respectively). Classifier miRNAs were tested in a separate cohort (N = 81). miRNA specificity was determined in non-acetaminophen liver injury and murine models. Sensitivity was tested by stratification of patients at hospital presentation (N = 67). From 1809 miRNAs, 75 were 3-fold or more increased and 46 were 3-fold or more decreased with APAP-TOX. A 16 miRNA classifier model accurately diagnosed APAP-TOX in the test cohort. In humans, the miRNAs with the largest increase (miR-122-5p, miR-885-5p, miR-151a-3p) and the highest rank in the classifier model (miR-382-5p) accurately reported non-acetaminophen liver injury and were unaffected by kidney injury. miR-122-5p was more sensitive than ALT for reporting liver injury at hospital presentation, especially combined with miR-483-3p. A miRNA panel was associated with human kidney dysfunction. In mice, miR-122-5p, miR-151a-3p and miR-382-5p specifically reported APAP toxicity - being unaffected by drug-induced kidney injury. Profiling of acetaminophen toxicity identified multiple miRNAs that report acute liver injury and potential biomarkers of drug-induced kidney injury. PMID:26489516

  16. Comprehensive microRNA profiling in acetaminophen toxicity identifies novel circulating biomarkers for human liver and kidney injury.

    PubMed

    Vliegenthart, A D B; Shaffer, J M; Clarke, J I; Peeters, L E J; Caporali, A; Bateman, D N; Wood, D M; Dargan, P I; Craig, D G; Moore, J K; Thompson, A I; Henderson, N C; Webb, D J; Sharkey, J; Antoine, D J; Park, B K; Bailey, M A; Lader, E; Simpson, K J; Dear, J W

    2015-10-22

    Our objective was to identify microRNA (miRNA) biomarkers of drug-induced liver and kidney injury by profiling the circulating miRNome in patients with acetaminophen overdose. Plasma miRNAs were quantified in age- and sex-matched overdose patients with (N = 27) and without (N = 27) organ injury (APAP-TOX and APAP-no TOX, respectively). Classifier miRNAs were tested in a separate cohort (N = 81). miRNA specificity was determined in non-acetaminophen liver injury and murine models. Sensitivity was tested by stratification of patients at hospital presentation (N = 67). From 1809 miRNAs, 75 were 3-fold or more increased and 46 were 3-fold or more decreased with APAP-TOX. A 16 miRNA classifier model accurately diagnosed APAP-TOX in the test cohort. In humans, the miRNAs with the largest increase (miR-122-5p, miR-885-5p, miR-151a-3p) and the highest rank in the classifier model (miR-382-5p) accurately reported non-acetaminophen liver injury and were unaffected by kidney injury. miR-122-5p was more sensitive than ALT for reporting liver injury at hospital presentation, especially combined with miR-483-3p. A miRNA panel was associated with human kidney dysfunction. In mice, miR-122-5p, miR-151a-3p and miR-382-5p specifically reported APAP toxicity - being unaffected by drug-induced kidney injury. Profiling of acetaminophen toxicity identified multiple miRNAs that report acute liver injury and potential biomarkers of drug-induced kidney injury.

  17. DEPTOR-related mTOR suppression is involved in metformin's anti-cancer action in human liver cancer cells

    SciTech Connect

    Obara, Akio; Fujita, Yoshihito; Abudukadier, Abulizi; Fukushima, Toru; Oguri, Yasuo; Ogura, Masahito; Harashima, Shin-ichi; Hosokawa, Masaya; Inagaki, Nobuya

    2015-05-15

    Metformin, one of the most commonly used drugs for patients with type 2 diabetes, recently has received much attention regarding its anti-cancer action. It is thought that the suppression of mTOR signaling is involved in metformin's anti-cancer action. Although liver cancer is one of the most responsive types of cancer for reduction of incidence by metformin, the molecular mechanism of the suppression of mTOR in liver remains unknown. In this study, we investigated the mechanism of the suppressing effect of metformin on mTOR signaling and cell proliferation using human liver cancer cells. Metformin suppressed phosphorylation of p70-S6 kinase, and ribosome protein S6, downstream targets of mTOR, and suppressed cell proliferation. We found that DEPTOR, an endogenous substrate of mTOR suppression, is involved in the suppressing effect of metformin on mTOR signaling and cell proliferation in human liver cancer cells. Metformin increases the protein levels of DEPTOR, intensifies binding to mTOR, and exerts a suppressing effect on mTOR signaling. This increasing effect of DEPTOR by metformin is regulated by the proteasome degradation system; the suppressing effect of metformin on mTOR signaling and cell proliferation is in a DEPTOR-dependent manner. Furthermore, metformin exerts a suppressing effect on proteasome activity, DEPTOR-related mTOR signaling, and cell proliferation in an AMPK-dependent manner. We conclude that DEPTOR-related mTOR suppression is involved in metformin's anti-cancer action in liver, and could be a novel target for anti-cancer therapy. - Highlights: • We elucidated a novel pathway of metformin's anti-cancer action in HCC cells. • DEPTOR is involved in the suppressing effect of metformin on mTOR signaling. • Metformin increases DEPTOR protein levels via suppression of proteasome activity. • DEPTOR-related mTOR suppression is involved in metformin's anti-cancer action.

  18. Lifelong maintenance of composition, function and cellular/subcellular distribution of proteasomes in human liver.

    PubMed

    Bellavista, Elena; Martucci, Morena; Vasuri, Francesco; Santoro, Aurelia; Mishto, Michele; Kloss, Alexander; Capizzi, Elisa; Degiovanni, Alessio; Lanzarini, Catia; Remondini, Daniel; Dazzi, Alessandro; Pellegrini, Sara; Cescon, Matteo; Capri, Miriam; Salvioli, Stefano; D'Errico-Grigioni, Antonia; Dahlmann, Burkhardt; Grazi, Gian Luca; Franceschi, Claudio

    2014-01-01

    Owing to organ shortage, livers from old donors are increasingly used for transplantation. The function and duration of such transplanted livers are apparently comparable to those from young donors, suggesting that, despite some morphological and structural age-related changes, no major functional changes do occur in liver with age. We tested this hypothesis by performing a comprehensive study on proteasomes, major cell organelles responsible for proteostasis, in liver biopsies from heart-beating donors. Oxidized and poly-ubiquitin conjugated proteins did not accumulate with age and the three major proteasome proteolytic activities were similar in livers from young and old donors. Analysis of proteasomes composition showed an age-related increased of β5i/α4 ratio, suggesting a shift toward proteasomes containing inducible subunits and a decreased content of PA28α subunit, mainly in the cytosol of hepatocytes. Thus our data suggest that, proteasomes activity is well preserved in livers from aged donors, concomitantly with subtle changes in proteasome subunit composition which might reflect the occurrence of a functional remodelling to maintain an efficient proteostasis. Gender differences are emerging and they deserve further investigations owing to the different aging trajectories between men and women. Finally, our data support the safe use of livers from old donors for transplantation.

  19. Frequent hepatocyte chimerism in long-term human liver allografts independent of graft outcome.

    PubMed

    Aini, Wulamujiang; Miyagawa-Hayashino, Aya; Ozeki, Munetaka; Tsuruyama, Tatsuaki; Tamaki, Keiji; Uemoto, Shinji; Haga, Hironori

    2013-03-01

    Microchimerism after liver transplantation is considered to promote graft tolerance or tissue repair, but its significance is controversial. By using multiplex polymerase chain reaction (PCR) of short tandem repeat (STR) loci after laser capture microdissection of hepatocyte nuclei, we compared the proportions of recipient-derived hepatocytes in long-term stable liver allografts and late dysfunctional allografts caused by chronic rejection or idiopathic post-transplantation hepatitis. Through fluorescence in situ hybridization (FISH), we also analyzed the presence of recipient-derived Y-positive hepatocytes in the biopsies of livers transplanted from female donors to male recipients. The study population comprised 24 pediatric liver transplant recipients who survived with the initial graft, whose 10-year protocol biopsy records were available, and who had normal liver function (stable graft, SG; n=13) or a late dysfunctional graft (LDG; n=11) with similar follow-up periods (mean 10.8years in the SG group and 11.2years in the LDG group). STR analysis revealed that hepatocyte chimerism occurred in 7 of 13 (54%) SGs and 5 of 11 (45%) LDGs (p=0.68). The proportion of hepatocyte chimerism was low, with a mean of 3% seen in 2 of 3 female-to-male transplanted livers (one each of SG and LDG). In conclusion, hepatocyte chimerism was a constant event. The extent of engraftment of recipient-derived hepatocytes does not seem to correlate with the degree of hepatic injury in long-term liver allografts.

  20. Radiosensitivity of hepatoma cell lines and human normal liver cell lines exposed to 12C6+ ions

    NASA Astrophysics Data System (ADS)

    Jing, X.; Yang, J.; Li, W.; Guo, C.; Dang, B.; Wang, J.; Zhou, L.; Wei, W.; Gao, Q.

    AIM To investigate the radiosensitivity of hepatoma cell lines and human normal liver cell lines METHODS Accelerated carbon ions by heavy ion research facility in Lanzhou HIRFL have high LET We employed it to study the radiosensitivity of hepatoma cell lines SMMC-7721 and human normal liver cell lines L02 using premature chromosome condensation technique PCC Cell survive was documented by a colony assay Chromatid breaks were measured by counting the number of chromatid breaks and isochromatid breaks immediately after prematurely chromosome condensed by Calyculin-A RESULTS The survival curve of the two cell lines presented a good linear relationship and the survival fraction of L02 is higher than that of SMMC-7721 Additionally the two types of G 2 phase chromosome breaks chromatid breaks and isochromatid breaks of L02 are lower than that of SMMC-7721 CONCLUSION Human normal liver cell line have high radioresistance than that of hepatoma cell line It imply that it is less damage to normal organs when radiotherapy to hepatoma

  1. Regulation by vascular endothelial growth factor of human colon cancer tumorigenesis in a mouse model of experimental liver metastasis.

    PubMed Central

    Warren, R S; Yuan, H; Matli, M R; Gillett, N A; Ferrara, N

    1995-01-01

    To investigate the relationship between angiogenesis and hepatic tumorigenesis, we examined the expression of vascular endothelial growth factor (VEGF) in 8 human colon carcinoma cell lines and in 30 human colorectal cancer liver metastases. Abundant message for VEGF was found in all tumors, localized to the malignant cells within each neoplasm. Two receptors for VEGF, KDR and flt1, were also demonstrated in most of the tumors examined. KDR and flt1 mRNA were limited to tumor endothelial cells and were more strongly expressed in the hepatic metastases than in the sinusoidal endothelium of the surrounding liver parenchyma. VEGF monoclonal antibody administration in tumor-bearing athymic mice led to a dose- and time-dependent inhibition of growth of subcutaneous xenografts and to a marked reduction in the number and size of experimental liver metastases. In hepatic metastases of VEGF antibody-treated mice, neither blood vessels nor expression of the mouse KDR homologue flk-1 could be demonstrated. These data indicate that VEGF is a commonly expressed angiogenic factor in human colorectal cancer metastases, that VEGF receptors are up-regulated as a concomitant of hepatic tumorigenesis, and that modulation of VEGF gene expression or activity may represent a potentially effective antineoplastic therapy in colorectal cancer. Images PMID:7535799

  2. Enzyme kinetic study of a new cardioprotective agent, KR-32570 using human liver microsomes and recombinant CYP isoforms.

    PubMed

    Kim, Hyojin; Seo, Kyung-Ah; Kim, Hyunmi; Lee, Hye Suk; Lee, Choong-Hwan; Shin, Jae-Gook; Liu, Kwang-Hyeon

    2007-04-01

    KR-32570 (5-(2-Methoxy-5-chlorophenyl)furan-2-ylcarbonyl)guanidine) is a new cardioprotective agent for preventing ischemia-reperfusion injury. Human liver microsomal incubation of KR-32570 in the presence of NADPH resulted in the formation of two metabolites, hydroxy-KR-32570 and O-desmethyl-KR-32570. In this study, a kinetic analysis of the metabolism of two metabolites from KR-32570 was performed in human liver microsomes, and recombinant CYP1A2, and CYP3A4. The metabolism for hydroxy- and O-desmethyl-KR-32570 formation from KR-32570 by human liver microsomes was best described by a Michaelis-Menten equation and a Hill equation, respectively. The Cl(int) values of hydroxy- and O-desmethyl-KR-32570 formation were similar to each other (0.03 vs 0.04 microL/min/pmol CYP, respectively). CYP3A4 mediated the formation of hydroxy-KR-32570 from KR-32570 with Cl(int) = 0.24 microL/min/pmol CYP3A4. The intrinsic clearance for O-desmethyl-KR-32570 formation by CYP1A2 was 0.83 AL/min/pmol CYP1A2. These findings suggest that CYP3A4 and CYP1A2 enzymes are major enzymes contributing to the metabolism of KR-32570.

  3. Cytokeratin 18-mediated disorganization of intermediate filaments is induced by degradation of plectin in human liver cells.

    PubMed

    Liu, Yi-Hsiang; Ho, Chin-Chin; Cheng, Chiung-Chi; Chao, Wei-Ting; Pei, Ren-Jeng; Hsu, Yung-Hsiang; Lai, Yih-Shyong

    2011-04-15

    Plectin is a cross-linking protein that organizes the cytoskeleton into a stable meshwork that helps maintain the uniform size and shape of cells. As cells of hepatocellular carcinoma are morphologically different from healthy human hepatocytes, we hypothesized that plectin deficiency and cytoskeletal disorganization underlies this pleomorphic transformation. To test this hypothesis we induced apoptosis as the most accessible pathway for creating plectin deficiency status in vivo. We analyzed expression levels and organization of plectin and other cytoskeletal elements, including intermediate filaments, microfilaments, and microtubules, after staurosporine-induced apoptosis in human Chang liver cells. The results revealed the expression of plectin and cytokeratin 18 were downregulated in hepatocellular carcinoma tissues in vivo. The expression of actin and tubulin, however, were not altered. In vitro analysis indicated that plectin and cytokeratin 18 were cleaved following staurosporine-treatment of human Chang liver cells. Time course experiments revealed that plectin was cleaved 2h earlier than cytokeratin 18. The organization of plectin and cytokeratin 18 networks collapsed after staurosporine-treatment. Conclusively, degradation of plectin induced by staurosporine-treatment in liver cells resulted in cytoskeleton disruption and induced morphological changes in these cells by affecting the expression and organization of cytokeratin 18.

  4. [Acetoacetate extract from Celastrus orbiculatus Thunb inhibits growth of RFP-xenografted human liver carcinoma].

    PubMed

    Wang, Mao-rong; Zhang, Xin; Liu, Yan-qing

    2012-05-01

    To investigate the inhibitory effect of acetoacetate extract from Celastrus orbiculatus Thumb (COT) on the growth of red fluorescent protein (RFP)-xenografted human hepatocellular carcinoma (HCC) in a nude mouse model. Human HCC HepG2 cells were transduced with RFP and inoculated into the liver of BALB/c nude mice. The tumor-bearing mice were randomly divided into five groups: control group (G1), oxaliplatin positive control group (G2; 25 mg/kg), COT low-dose group (G3; 20 mg/kg), COT high-dose group (G4; 40 mg/kg), and COT early treatment group (G5; 20 mg/kg). The early treatment group received oral COT from day 2 post-tumor implantation. All other mice were treated from day 20 post-tumor implantation. Growth of xenografted tumors was monitored weekly by in vivo real-time fluorescence imaging technology. At the end of the four-week treatment period, all mice were sacrificed and tumor tissues were collected and weighed. The two-sided t-test was used to evaluate intergroup differences in tumor volumes, final tumor weights, and final body weights. Mice treated with COT had significantly smaller xenografted tumors. On day 45 post-implantation, the mean tumor volumes (mm3) in the different groups were: G1, 803.1+/-512.3 ; G2, 83.8+/-23.5; G3, 852.7+/-502.6; G4, 410.0+/-231.6; and G5, 120.5+/-60.1. The mean tumor weights (g) were: G1, 0.95+/-0.49; G2, 0.36+/-0.09; G3, 0.67+/-0.29; G4, 0.48+/-0.15; and G5, 0.38+/-0.11. The differences in tumor weights from G2, G4 and G5 were significantly less than the weight in G1 (P less than 0.05); however, there was no significant differences between the tumor weights in G2, G4 and G5 (P more than 0.05). The tumor weight from the G2 group was significantly less than that of the G3 group (P less than 0.05). COT significantly inhibited the proliferation of human HCC in a nude mouse model. Early treatment with COT produced a more robust inhibitory effect, which was very similar to that achieved with oxaliplatin treatment.

  5. Granulomas in the livers of humans and Fischer rats associated with the ingestion of mineral hydrocarbons: a comparison.

    PubMed

    Fleming, K A; Zimmerman, H; Shubik, P

    1998-02-01

    Ninety-day feeding studies were conducted in Fischer 344 rats using a series of highly refined mineral hydrocarbons which included mineral oils and waxes representative of those used in consumer products and food applications. The series included materials which had been refined by oleum or hydrogenation. The materials tested were representative of the range of carbon chain lengths, molecular weights, and viscosities which are currently in use. Findings revealed the presence of granulomatous lesions in the liver and histiocytosis in the lymph nodes. Some mineral hydrocarbons did not induce any lesions; others induced relatively minor effects; and a low melting point wax induced the largest lesions in both liver and mesenteric lymph nodes, with inflammation and areas of focal necrosis in the livers. The majority of lesions reported were associated with the highest dose levels used. These studies are in contrast to studies in Sprague-Dawley rats in which comparable doses did not induce similar lesions, indicating marked strain variability. Lipogranulomas associated with the ingestion of mineral oil have been reported in humans. The comparative morphology of the lesions seen in the Fischer rat study and those observed in the human are discussed and differences are highlighted. The lesions in the human are not believed to progress to lesions of clinical significance. The pathogenesis of the lesions induced in Fischer rats and in humans is discussed and it is concluded that the majority, if not all of the lesions, in the rats are of no significance for humans. The possibility that a small proportion of cases of granulomatous hepatitis in humans may represent an atypical response to mineral hydrocarbons may need further investigation.

  6. Tissue-resident Eomes(hi) T-bet(lo) CD56(bright) NK cells with reduced proinflammatory potential are enriched in the adult human liver.

    PubMed

    Harmon, Cathal; Robinson, Mark W; Fahey, Ronan; Whelan, Sarah; Houlihan, Diarmaid D; Geoghegan, Justin; O'Farrelly, Cliona

    2016-09-01

    The adult human liver is enriched with natural killer (NK) cells, accounting for 30-50% of hepatic lymphocytes, which include tissue-resident hepatic NK-cell subpopulations, distinct from peripheral blood NK cells. In murine liver, a subset of liver-resident hepatic NK cells have altered expression of the two highly related T-box transcription factors, T-bet and eomesodermin (Eomes). Here, we investigate the heterogeneity of T-bet and Eomes expression in NK cells from healthy adult human liver with a view to identifying human liver-resident populations. Hepatic NK cells were isolated from donor liver perfusates and biopsies obtained during orthotopic liver transplantation (N = 28). Hepatic CD56(bright) NK cells were Eomes(hi) T-bet(lo) , a phenotype virtually absent from peripheral blood. These NK cells express the chemokine receptor CXCR6 (chemokine (C-X-C motif) receptor 6), a marker of tissue residency, which is absent from hepatic CD56(dim) and blood NK cells. Compared to blood populations, these hepatic CD56(bright) NK cells have increased expression of activatory receptors (NKp44, NKp46, and NKG2D). They show reduced ability to produce IFN-γ but enhanced degranulation in response to challenge with target cells. This functionally distinct population of hepatic NK cells constitutes 20-30% of the total hepatic lymphocyte repertoire and represents a tissue-resident immune cell population adapted to the tolerogenic liver microenvironment.

  7. Medium-chain fatty acid reduces lipid accumulation by regulating expression of lipid-sensing genes in human liver cells with steatosis.

    PubMed

    Wang, Baogui; Fu, Jing; Li, Lumin; Gong, Deming; Wen, Xuefang; Yu, Ping; Zeng, Zheling

    2016-01-01

    Accumulation of lipids in the liver can lead to cell dysfunction and steatosis, an important factor in pathogenesis causing non-alcoholic fatty liver disease. The mechanisms related to lipid deposition in the liver, however, remain poorly understood. This study was aimed to investigate the effects of medium-chain fatty acid (MCFA) on the lipolysis and expression of lipid-sensing genes in human liver cells with steatosis. A cellular steatosis model, which is suitable to experimentally investigate the impact of fat accumulation in the liver, was established in human normal liver cells (LO2 cells) with a mixture of free fatty acids (oleate/palmitate, 2:1) at 200 μm for 24 h incubation. MCFA was found to down-regulate expression of liver X receptor-α, sterol regulatory element binding protein-1, acetyl-CoA carboxylase, fatty acid synthase, CD 36 and lipoprotein lipase in this cellular model, and have positive effects on adipose triglyceride lipase and hormone-sensitive lipase. These results suggest that MCFA may reduce lipid accumulation by regulating key lipid-sensing genes in human liver cells with steatosis. PMID:26932533

  8. Critically Assessing the Predictive Power of QSAR Models for Human Liver Microsomal Stability.

    PubMed

    Liu, Ruifeng; Schyman, Patric; Wallqvist, Anders

    2015-08-24

    To lower the possibility of late-stage failures in the drug development process, an up-front assessment of absorption, distribution, metabolism, elimination, and toxicity is commonly implemented through a battery of in silico and in vitro assays. As in vitro data is accumulated, in silico quantitative structure-activity relationship (QSAR) models can be trained and used to assess compounds even before they are synthesized. Even though it is generally recognized that QSAR model performance deteriorates over time, rigorous independent studies of model performance deterioration is typically hindered by the lack of publicly available large data sets of structurally diverse compounds. Here, we investigated predictive properties of QSAR models derived from an assembly of publicly available human liver microsomal (HLM) stability data using variable nearest neighbor (v-NN) and random forest (RF) methods. In particular, we evaluated the degree of time-dependent model performance deterioration. Our results show that when evaluated by 10-fold cross-validation with all available HLM data randomly distributed among 10 equal-sized validation groups, we achieved high-quality model performance from both machine-learning methods. However, when we developed HLM models based on when the data appeared and tried to predict data published later, we found that neither method produced predictive models and that their applicability was dramatically reduced. On the other hand, when a small percentage of randomly selected compounds from data published later were included in the training set, performance of both machine-learning methods improved significantly. The implication is that 1) QSAR model quality should be analyzed in a time-dependent manner to assess their true predictive power and 2) it is imperative to retrain models with any up-to-date experimental data to ensure maximum applicability. PMID:26170251

  9. Lovastatin increases arachidonic acid levels and stimulates thromboxane synthesis in human liver and monocytic cell lines.

    PubMed Central

    Hrboticky, N; Tang, L; Zimmer, B; Lux, I; Weber, P C

    1994-01-01

    The effect of lovastatin (LOV), the inhibitor of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, on linoleic acid (LA, 18:2n-6) metabolism was examined in human monocytic Mono Mac 6 (MM6) and hepatoma Hep G2 cells. The desaturation of LA was examined after LOV (72 h, 10 microM) or dimethylsulfoxide (LOV carrier, < 0.1%) and [14C]LA (last 18 h, 0.3 microCi, 5 microM). In both cell lines, LOV reduced the percentage of 14C label associated with LA and increased the percentage of label in the 20:4n-6 and the 22:5n-6 fractions. In Hep G2 but not MM6 cells, this effect was fully reversible by means of coincubation with mevalonic acid (500 microM), but not with cholesterol or lipoproteins. In both cell lines, the LOV-mediated increase in LA desaturation resulted in dose-dependent reductions of LA and elevations of AA in cellular phospholipids. The lipids secreted by LOV-treated Hep G2 cells were also enriched in arachidonic acid (AA). In the MM6 cells, LOV increased release of thromboxane upon stimulation with the calcium ionophore A23187. In summary, our findings of higher LA desaturation and AA enrichment of lipids secreted by the Hep G2 cells suggest that LOV treatment may increase the delivery of AA from the liver to extrahepatic tissues. The changes in membrane fatty acid composition can influence a variety of cellular functions, such as eicosanoid synthesis in monocytic cells. The mechanism appears to be related to the reduced availability of intermediates of cholesterogenesis. PMID:8282787

  10. The Nonspecific Binding of Tyrosine Kinase Inhibitors to Human Liver Microsomes.

    PubMed

    Burns, Kushari; Nair, Pramod C; Rowland, Andrew; Mackenzie, Peter I; Knights, Kathleen M; Miners, John O

    2015-12-01

    Drugs and other chemicals frequently bind nonspecifically to the constituents of an in vitro incubation mixture, particularly the enzyme source [e.g., human liver microsomes (HLM)]. Correction for nonspecific binding (NSB) is essential for the accurate calculation of the kinetic parameters Km, Clint, and Ki. Many tyrosine kinase inhibitors (TKIs) are lipophilic organic bases that are nonionized at physiologic pH. Attempts to measure the NSB of several TKIs to HLM by equilibrium dialysis proved unsuccessful, presumably due to the limited aqueous solubility of these compounds. Thus, the addition of detergents to equilibrium dialysis samples was investigated as an approach to measure the NSB of TKIs. The binding of six validation set nonionized lipophilic bases (felodipine, isradipine, loratidine, midazolam, nifedipine, and pazopanib) to HLM (0.25 mg/ml) was shown to be unaffected by the addition of CHAPS (6 mM) to the dialysis medium. This approach was subsequently applied to measurement of the binding of axitinib, dabrafenib, erlotinib, gefitinib, ibrutinib, lapatinib, nilotinib, nintedanib, regorafenib, sorafenib, and trametinib to HLM (0.25 mg/ml). As with the validation set drugs, attainment of equilibrium was demonstrated in HLM-HLM and buffer-buffer control dialysis experiments. Values of the fraction unbound to HLM ranged from 0.14 (regorafenib and sorafenib) to 0.93 (nintedanib), and were generally consistent with the known physicochemical determinants of drug NSB. The extensive NSB of many TKIs to HLM underscores the importance of correction for TKI binding to HLM and, presumably, other enzyme sources present in in vitro incubation mixtures.

  11. Glucuronidation of the aspirin metabolite salicylic acid by expressed UDP-glucuronosyltransferases and human liver microsomes.

    PubMed

    Kuehl, Gwendolyn E; Bigler, Jeannette; Potter, John D; Lampe, Johanna W

    2006-02-01

    Acetylsalicylic acid (aspirin) is a common nonsteroidal anti-inflammatory drug used for treatment of pain and arthritis. In the body, acetylsalicylic acid is rapidly deacetylated to form salicylic acid. Both compounds have been proposed as anti-inflammatory agents. Major metabolites of salicylic acid are its acyl and phenolic glucuronide conjugates. Formation of these conjugates, catalyzed by UDP-glucuronosyltransferases (UGTs), decreases the amount of pharmacologically active salicylic acid present. We aimed to identify the UGTs catalyzing the glucuronidation of salicylic acid using both heterologously expressed enzymes and pooled human liver microsomes (HLMs) and to develop a liquid chromatography-tandem mass spectrometry method to quantify glucuronidation activity of UGTs 1A1, 1A3, 1A4, 1A6, 1A7, 1A8, 1A9, 1A10, 2B4, 2B7, 2B15, and 2B17 Supersomes. All UGTs tested, except 1A4, 2B15, and 2B17, catalyzed salicylic acid phenolic and acyl glucuronidation. Ratios of salicylic acid phenolic to acyl glucuronide formation varied more than 12-fold from 0.5 for UGT1A6 to 6.1 for UGT1A1. These results suggest that all UGTs except 1A4, 2B15, and 2B17 might be involved in the glucuronidation of salicylic acid in vivo. From comparisons of apparent Km values determined in pooled HLMs and in expressed UGTs, UGT2B7 was suggested as a likely catalyst of salicylic acid acyl glucuronidation, whereas multiple UGTs were suggested as catalysts of phenolic glucuronidation. The results of this UGT screening may help target future evaluation of the effects of UGT polymorphisms on response to aspirin in clinical and population-based studies.

  12. Mechanism of cytotoxic action of crambescidin-816 on human liver-derived tumour cells

    PubMed Central

    Rubiolo, J A; López-Alonso, H; Roel, M; Vieytes, M R; Thomas, O; Ternon, E; Vega, F V; Botana, L M

    2014-01-01

    Background and Purpose Marine sponges have evolved the capacity to produce a series of very efficient chemicals to combat viruses, bacteria, and eukaryotic organisms. It has been demonstrated that several of these compounds have anti-neoplastic activity. The highly toxic sponge Crambe crambe has been the source of several molecules named crambescidins. Of these, crambescidin-816 has been shown to be cytotoxic for colon carcinoma cells. To further investigate the potential anti-carcinogenic effect of crambescidin-816, we analysed its effect on the transcription of HepG2 cells by microarray analysis followed by experiments guided by the results obtained. Experimental Approach After cytotoxicity determination, a transcriptomic analysis was performed to test the effect of crambescidin-816 on the liver-derived tumour cell HepG2. Based on the results obtained, we analysed the effect of crambescidin-816 on cell-cell adhesion, cell-matrix adhesion, and cell migration by Western blot, confocal microscopy, flow cytometry and transmission electron microscopy. Cytotoxicity and cell migration were also studied in a variety of other cell lines derived from human tumours. Key Results Crambescidin-816 had a cytotoxic effect on all the cell lines studied. It inhibited cell-cell adhesion, interfered with the formation of tight junctions, and cell-matrix adhesion, negatively affecting focal adhesions. It also altered the cytoskeleton dynamics. As a consequence of all these effects on cells crambescidin-816 inhibited cell migration. Conclusions and Implications The results indicate that crambescidin-816 is active against tumour cells and implicate a new mechanism for the anti-tumour effect of this compound. PMID:24328908

  13. Reversible inhibition of three important human liver cytochrome p450 enzymes by tiliroside.

    PubMed

    Sun, Dong-Xue; Lu, Jin-Cai; Fang, Zhong-Ze; Zhang, Yan-Yan; Cao, Yun-Feng; Mao, Yu-Xi; Zhu, Liang-Liang; Yin, Jun; Yang, Ling

    2010-11-01

    Tiliroside, an active flavonoid extensively found in many medicinal plants including Helichrysum italicum, Geranium mexicanum and Helianthemum glomeratum, has been demonstrated to exert multiple biological effects including antiinflammatory, antimicrobial, antioxidant and antitumor activities. Cytochrome P450 (CYP) enzymes play an important role in the Phase I oxidation metabolism of a wide range of xenobiotics and inhibition of CYP isoforms might influence the elimination of drugs and induce serious adverse drug response. The inhibition of seven CYP isoforms (CYP3A4, CYP1A2, CYP2A6, CYP2D6, CYP2C9, CYP2C8 and CYP2E1) by tiliroside was investigated using in vitro human liver microsomal incubation assays. The results showed that tiliroside strongly inhibited the activity of CYP3A4 (IC(50) = 9.0 ± 1.7 μm), CYP2C8 (IC(50) = 12.1 ± 0.9 μm) and CYP2C9 (IC(50) = 10.2 ± 0.9 μm) with other CYP isoforms negligibly influenced. Further kinetic analysis showed that inhibition of these three CYP isoforms by tiliroside is best fit to a competitive way. The K(i) value was calculated to be 5.5 μm, 3.3 μm, 9.4 μm for CYP3A4, CYP2C9 and CYP2C8, respectively. The relatively low K(i) values suggested that tiliroside might induce drug-drug interactions with many clinically used drugs which are mainly metabolized by these three CYP isoforms. Therefore, attention should be given to the probable drug-drug interaction between tiliroside-containing herbs and substrates of CYP3A4, CYP2C9 and CYP2C8.

  14. Evaluation of inhibitory effects of caffeic acid and quercetin on human liver cytochrome p450 activities.

    PubMed

    Rastogi, Himanshu; Jana, Snehasis

    2014-12-01

    When herbal drugs and conventional allopathic drugs are used together, they can interact in our body which can lead to the potential for herb-drug interactions. This work was conducted to evaluate the herb-drug interaction potential of caffeic acid and quercetin mediated by cytochrome P450 (CYP) inhibition. Human liver microsomes (HLMs) were added to each selective probe substrates of cytochrome P450 enzymes with or without of caffeic acid and quercetin. IC50 , Ki values, and the types of inhibition were determined. Both caffeic acid and quercetin were potent competitive inhibitors of CYP1A2 (Ki = 1.16 and 0.93 μM, respectively) and CYP2C9 (Ki = 0.95 and 1.67 μM, respectively). Caffeic acid was a potent competitive inhibitor of CYP2D6 (Ki = 1.10 μM) and a weak inhibitor of CYP2C19 and CYP3A4 (IC50  > 100 μM). Quercetin was a potent competitive inhibitor of CYP 2C19 and CYP3A4 (Ki = 1.74 and 4.12 μM, respectively) and a moderate competitive inhibitor of CYP2D6 (Ki = 18.72 μM). These findings might be helpful for safe and effective use of polyphenols in clinical practice. Our data indicated that it is necessary to study the in vivo interactions between drugs and pharmaceuticals with dietary polyphenols. PMID:25196644

  15. Glucuronidation of the aspirin metabolite salicylic acid by expressed UDP-glucuronosyltransferases and human liver microsomes.

    PubMed

    Kuehl, Gwendolyn E; Bigler, Jeannette; Potter, John D; Lampe, Johanna W

    2006-02-01

    Acetylsalicylic acid (aspirin) is a common nonsteroidal anti-inflammatory drug used for treatment of pain and arthritis. In the body, acetylsalicylic acid is rapidly deacetylated to form salicylic acid. Both compounds have been proposed as anti-inflammatory agents. Major metabolites of salicylic acid are its acyl and phenolic glucuronide conjugates. Formation of these conjugates, catalyzed by UDP-glucuronosyltransferases (UGTs), decreases the amount of pharmacologically active salicylic acid present. We aimed to identify the UGTs catalyzing the glucuronidation of salicylic acid using both heterologously expressed enzymes and pooled human liver microsomes (HLMs) and to develop a liquid chromatography-tandem mass spectrometry method to quantify glucuronidation activity of UGTs 1A1, 1A3, 1A4, 1A6, 1A7, 1A8, 1A9, 1A10, 2B4, 2B7, 2B15, and 2B17 Supersomes. All UGTs tested, except 1A4, 2B15, and 2B17, catalyzed salicylic acid phenolic and acyl glucuronidation. Ratios of salicylic acid phenolic to acyl glucuronide formation varied more than 12-fold from 0.5 for UGT1A6 to 6.1 for UGT1A1. These results suggest that all UGTs except 1A4, 2B15, and 2B17 might be involved in the glucuronidation of salicylic acid in vivo. From comparisons of apparent Km values determined in pooled HLMs and in expressed UGTs, UGT2B7 was suggested as a likely catalyst of salicylic acid acyl glucuronidation, whereas multiple UGTs were suggested as catalysts of phenolic glucuronidation. The results of this UGT screening may help target future evaluation of the effects of UGT polymorphisms on response to aspirin in clinical and population-based studies. PMID:16258079

  16. Critically Assessing the Predictive Power of QSAR Models for Human Liver Microsomal Stability.

    PubMed

    Liu, Ruifeng; Schyman, Patric; Wallqvist, Anders

    2015-08-24

    To lower the possibility of late-stage failures in the drug development process, an up-front assessment of absorption, distribution, metabolism, elimination, and toxicity is commonly implemented through a battery of in silico and in vitro assays. As in vitro data is accumulated, in silico quantitative structure-activity relationship (QSAR) models can be trained and used to assess compounds even before they are synthesized. Even though it is generally recognized that QSAR model performance deteriorates over time, rigorous independent studies of model performance deterioration is typically hindered by the lack of publicly available large data sets of structurally diverse compounds. Here, we investigated predictive properties of QSAR models derived from an assembly of publicly available human liver microsomal (HLM) stability data using variable nearest neighbor (v-NN) and random forest (RF) methods. In particular, we evaluated the degree of time-dependent model performance deterioration. Our results show that when evaluated by 10-fold cross-validation with all available HLM data randomly distributed among 10 equal-sized validation groups, we achieved high-quality model performance from both machine-learning methods. However, when we developed HLM models based on when the data appeared and tried to predict data published later, we found that neither method produced predictive models and that their applicability was dramatically reduced. On the other hand, when a small percentage of randomly selected compounds from data published later were included in the training set, performance of both machine-learning methods improved significantly. The implication is that 1) QSAR model quality should be analyzed in a time-dependent manner to assess their true predictive power and 2) it is imperative to retrain models with any up-to-date experimental data to ensure maximum applicability.

  17. Role of human albumin in the management of complications of liver cirrhosis.

    PubMed

    Bernardi, Mauro; Ricci, Carmen S; Zaccherini, Giacomo

    2014-12-01

    Albumin is a negatively charged, relatively small protein synthesized by liver cells. Is the most abundant protein in extracellular fluid and accounts for about 70% of the plasma colloid osmotic pressure. Therefore it plays a crucial role in regulating fluid distribution in the body. In addition, albumin possesses functional domains with important non-oncotic properties, such as potent anti-oxydant and scavenging activities, binding of highly toxic reactive metal species and a great amount of endogenous and exogenous substances. We have recently learned that albumin in cirrhosis undergoes a number of post-transcriptional changes that greatly impair its non-oncotic properties. The overall assessment of these changes clearly shows that the relative abundance of the native form of albumin is significantly reduced in hospitalized patients with cirrhosis and that these abnormalities worsen in parallel with the increasing severity of the disease. Thus, it is time to abandon the concept of serum albumin concentration and refer to the effective albumin concentration, that is the native intact albumin. Given the pathophysiological context in which we use human albumin in patients with cirrhosis, who are characterized by peripheral vasodilation and a low-grade but sustained inflammatory state, the use of albumin in patients with cirrhosis should aim at enhancing effective hypovolemia and exploiting its antioxidant and scavenging activities. The indications for the use of albumin in cirrhosis that clearly emerge from evidence-based medicine are represented by conditions characterized by an acute aggravation of effective hypovolemia and inflammation, such as such post-paracentesis circulatory dysfunction, spontaneous bacterial peritonitis, and hepatorenal syndrome. Other indications to the use of albumin that still require further studies are represented by bacterial infections other than spontaneous bacterial peritonitis, hepatic encephalopathy and long-term treatment of

  18. The Nonspecific Binding of Tyrosine Kinase Inhibitors to Human Liver Microsomes.

    PubMed

    Burns, Kushari; Nair, Pramod C; Rowland, Andrew; Mackenzie, Peter I; Knights, Kathleen M; Miners, John O

    2015-12-01

    Drugs and other chemicals frequently bind nonspecifically to the constituents of an in vitro incubation mixture, particularly the enzyme source [e.g., human liver microsomes (HLM)]. Correction for nonspecific binding (NSB) is essential for the accurate calculation of the kinetic parameters Km, Clint, and Ki. Many tyrosine kinase inhibitors (TKIs) are lipophilic organic bases that are nonionized at physiologic pH. Attempts to measure the NSB of several TKIs to HLM by equilibrium dialysis proved unsuccessful, presumably due to the limited aqueous solubility of these compounds. Thus, the addition of detergents to equilibrium dialysis samples was investigated as an approach to measure the NSB of TKIs. The binding of six validation set nonionized lipophilic bases (felodipine, isradipine, loratidine, midazolam, nifedipine, and pazopanib) to HLM (0.25 mg/ml) was shown to be unaffected by the addition of CHAPS (6 mM) to the dialysis medium. This approach was subsequently applied to measurement of the binding of axitinib, dabrafenib, erlotinib, gefitinib, ibrutinib, lapatinib, nilotinib, nintedanib, regorafenib, sorafenib, and trametinib to HLM (0.25 mg/ml). As with the validation set drugs, attainment of equilibrium was demonstrated in HLM-HLM and buffer-buffer control dialysis experiments. Values of the fraction unbound to HLM ranged from 0.14 (regorafenib and sorafenib) to 0.93 (nintedanib), and were generally consistent with the known physicochemical determinants of drug NSB. The extensive NSB of many TKIs to HLM underscores the importance of correction for TKI binding to HLM and, presumably, other enzyme sources present in in vitro incubation mixtures. PMID:26443648

  19. Improvement of Shear Wave Motion Detection Using Harmonic Imaging in Healthy Human Liver.

    PubMed

    Amador, Carolina; Song, Pengfei; Meixner, Duane D; Chen, Shigao; Urban, Matthew W

    2016-05-01

    Quantification of liver elasticity is a major application of shear wave elasticity imaging (SWEI) to non-invasive assessment of liver fibrosis stages. SWEI measurements can be highly affected by ultrasound image quality. Ultrasound harmonic imaging has exhibited a significant improvement in ultrasound image quality as well as for SWEI measurements. This was previously illustrated in cardiac SWEI. The purpose of this study was to evaluate liver shear wave particle displacement detection and shear wave velocity (SWV) measurements with fundamental and filter-based harmonic ultrasound imaging. In a cohort of 17 patients with no history of liver disease, a 2.9-fold increase in maximum shear wave displacement, a 0.11 m/s decrease in the overall interquartile range and median SWV and a 17.6% increase in the success rate of SWV measurements were obtained when filter-based harmonic imaging was used instead of fundamental imaging.

  20. [Determination of lithium content in human biological objects (liver, kidney) by the method of flame photometry].

    PubMed

    Luzanova, I S; Voznesenskaia, T V; Menitskaia, V I; Pushchinskaia, E V

    2007-01-01

    The authors give a method of determination of the content of lithium in biological objects (liver, kidney) by the method of flame photometry. It is possible to use this method in forensic medicine in cases of acute intoxication.

  1. Transcriptional profiling of mouse and human livers at different life stages

    EPA Science Inventory

    In the presence offoreign compounds,metabolichomeostasis oftheorganismismaintained by the liver's ability to detoxify and eliminate these xenobiotics. This is accomplished, in part, by the expression ofxenobiotic metabolizing enzymes (XMEs), which metabolize xenobiotics and det...

  2. Improvement of Shear Wave Motion Detection Using Harmonic Imaging in Healthy Human Liver.

    PubMed

    Amador, Carolina; Song, Pengfei; Meixner, Duane D; Chen, Shigao; Urban, Matthew W

    2016-05-01

    Quantification of liver elasticity is a major application of shear wave elasticity imaging (SWEI) to non-invasive assessment of liver fibrosis stages. SWEI measurements can be highly affected by ultrasound image quality. Ultrasound harmonic imaging has exhibited a significant improvement in ultrasound image quality as well as for SWEI measurements. This was previously illustrated in cardiac SWEI. The purpose of this study was to evaluate liver shear wave particle displacement detection and shear wave velocity (SWV) measurements with fundamental and filter-based harmonic ultrasound imaging. In a cohort of 17 patients with no history of liver disease, a 2.9-fold increase in maximum shear wave displacement, a 0.11 m/s decrease in the overall interquartile range and median SWV and a 17.6% increase in the success rate of SWV measurements were obtained when filter-based harmonic imaging was used instead of fundamental imaging. PMID:26803391

  3. Sphingosine kinase-1, S1P transporter spinster homolog 2 and S1P2 mRNA expressions are increased in liver with advanced fibrosis in human

    PubMed Central

    Sato, Masaya; Ikeda, Hitoshi; Uranbileg, Baasanjav; Kurano, Makoto; Saigusa, Daisuke; Aoki, Junken; Maki, Harufumi; Kudo, Hiroki; Hasegawa, Kiyoshi; Kokudo, Norihiro; Yatomi, Yutaka

    2016-01-01

    The role of sphingosine 1-phosphate (S1P) in liver fibrosis or inflammation was not fully examined in human. Controversy exists which S1P receptors, S1P1 and S1P3 vs S1P2, would be importantly involved in its mechanism. To clarify these matters, 80 patients who received liver resection for hepatocellular carcinoma and 9 patients for metastatic liver tumor were enrolled. S1P metabolism was analyzed in background, non-tumorous liver tissue. mRNA levels of sphingosine kinase 1 (SK1) but not SK2 were increased in livers with fibrosis stages 3–4 compared to those with 0–2 and to normal liver. However, S1P was not increased in advanced fibrotic liver, where mRNA levels of S1P transporter spinster homolog 2 (SPNS2) but not S1P-degrading enzymes were enhanced. Furthermore, mRNA levels of S1P2 but not S1P1 or S1P3 were increased in advanced fibrotic liver. These increased mRNA levels of SK1, SPNS2 and S1P2 in fibrotic liver were correlated with α-smooth muscle actin mRNA levels in liver, and with serum ALT levels. In conclusion, S1P may be actively generated, transported to outside the cells, and bind to its specific receptor in human liver to play a role in fibrosis or inflammation. Altered S1P metabolism in fibrotic liver may be their therapeutic target. PMID:27562371

  4. Sphingosine kinase-1, S1P transporter spinster homolog 2 and S1P2 mRNA expressions are increased in liver with advanced fibrosis in human.

    PubMed

    Sato, Masaya; Ikeda, Hitoshi; Uranbileg, Baasanjav; Kurano, Makoto; Saigusa, Daisuke; Aoki, Junken; Maki, Harufumi; Kudo, Hiroki; Hasegawa, Kiyoshi; Kokudo, Norihiro; Yatomi, Yutaka

    2016-01-01

    The role of sphingosine 1-phosphate (S1P) in liver fibrosis or inflammation was not fully examined in human. Controversy exists which S1P receptors, S1P1 and S1P3 vs S1P2, would be importantly involved in its mechanism. To clarify these matters, 80 patients who received liver resection for hepatocellular carcinoma and 9 patients for metastatic liver tumor were enrolled. S1P metabolism was analyzed in background, non-tumorous liver tissue. mRNA levels of sphingosine kinase 1 (SK1) but not SK2 were increased in livers with fibrosis stages 3-4 compared to those with 0-2 and to normal liver. However, S1P was not increased in advanced fibrotic liver, where mRNA levels of S1P transporter spinster homolog 2 (SPNS2) but not S1P-degrading enzymes were enhanced. Furthermore, mRNA levels of S1P2 but not S1P1 or S1P3 were increased in advanced fibrotic liver. These increased mRNA levels of SK1, SPNS2 and S1P2 in fibrotic liver were correlated with α-smooth muscle actin mRNA levels in liver, and with serum ALT levels. In conclusion, S1P may be actively generated, transported to outside the cells, and bind to its specific receptor in human liver to play a role in fibrosis or inflammation. Altered S1P metabolism in fibrotic liver may be their therapeutic target. PMID:27562371

  5. Apoptosis induction by silica nanoparticles mediated through reactive oxygen species in human liver cell line HepG2

    SciTech Connect

    Ahmad, Javed; Ahamed, Maqusood; Akhtar, Mohd Javed; Alrokayan, Salman A.; Siddiqui, Maqsood A.; Musarrat, Javed; Al-Khedhairy, Abdulaziz A.

    2012-03-01

    Silica nanoparticles are increasingly utilized in various applications including agriculture and medicine. In vivo studies have shown that liver is one of the primary target organ of silica nanoparticles. However, possible mechanisms of hepatotoxicity caused by silica nanoparticles still remain unclear. In this study, we explored the reactive oxygen species (ROS) mediated apoptosis induced by well-characterized 14 nm silica nanoparticles in human liver cell line HepG2. Silica nanoparticles (25–200 μg/ml) induced a dose-dependent cytotoxicity in HepG2 cells. Silica nanoparticles were also found to induce oxidative stress in dose-dependent manner indicated by induction of ROS and lipid peroxidation and depletion of glutathione (GSH). Quantitative real-time PCR and immunoblotting results showed that both the mRNA and protein expressions of cell cycle checkpoint gene p53 and apoptotic genes (bax and caspase-3) were up-regulated while the anti-apoptotic gene bcl-2 was down-regulated in silica nanoparticles treated cells. Moreover, co-treatment of ROS scavenger vitamin C significantly attenuated the modulation of apoptotic markers along with the preservation of cell viability caused by silica nanoparticles. Our data demonstrated that silica nanoparticles induced apoptosis in human liver cells, which is ROS mediated and regulated through p53, bax/bcl-2 and caspase pathways. This study suggests that toxicity mechanisms of silica nanoparticles should be further investigated at in vivo level. -- Highlights: ► We explored the mechanisms of toxicity caused by silica NPs in human liver HepG2 cells. ► Silica NPs induced a dose-dependent cytotoxicity in HepG2 cells. ► Silica NPs induced ROS generation and oxidative stress in a dose-dependent manner. ► Silica NPs were also modulated apoptosis markers both at mRNA and protein levels. ► ROS mediated apoptosis induced by silica NPs was preserved by vitamin C.

  6. Identification of Human UDP-Glucuronosyltransferase 1A4 as the Major Isozyme Responsible for the Glucuronidation of 20(S)-Protopanaxadiol in Human Liver Microsomes

    PubMed Central

    Li, Jia; He, Chunyong; Fang, Lianxiang; Yang, Li; Wang, Zhengtao

    2016-01-01

    20(S)-protopanaxadiol (PPD), one of the representative aglycones of ginsenosides, has a broad spectrum of pharmacological activities. Although phase I metabolism has been investigated extensively, information regarding phase II metabolism of this compound remains to be elucidated. Here, a glucuronidated metabolite of PPD in human liver microsomes (HLMs) and rat liver microsomes (RLMs) was unambiguously identified as PPD-3-O-β-d-glucuronide by nuclear magnetic resonance spectroscopy and high resolution mass spectrometry. The chemical inhibition and recombinant human UDP-Glucuronosyltransferase (UGT) isoforms assay showed that the PPD glucuronidation was mainly catalyzed by UGT1A4 in HLM, whereas UGT1A3 showed weak catalytic activity. In conclusion, PPD-3-O-β-d-glucuronide was first identified as the principal glucuronidation metabolite of PPD in HLMs, which was catalyzed by UGT1A4. PMID:27005621

  7. Microarray Analysis of Human Liver Cells irradiated by 80MeV/u Carbon Ions

    NASA Astrophysics Data System (ADS)

    Wang, Xiao; Tian, Xiaoling; Kong, Fuquan; Li, Qiang; Jin, Xiaodong; Dai, Zhongying; Zhang, Hong; Yang, Mingjian; Zhao, Kui

    Objective Biological effect of heavy ion beam has the important significance for cancer therapy and space exploring owing its high LET and RBE, low OER, especially forming Bragg spike at the end of the tracks of charged particles. More serious damage for cells are induced by heavy ions and difficult repair than other irradiation such as X-ray and ν-ray . To explore the molecular mechanism of biological effect caused by heavy ionizing radiation (HIR) and to construct the gene expression profile database of HIR-induced human liver cells L02 by microarray analysis. Methods In this study, L02 cells were irradiated by 80MeV/u carbon ions at 5 Gy delivered by HIRFL (Heavy Ion Research Facility in Lanzhou) at room temperature. Total RNAs of cells incubated 6 hours and 24hours after irradiation were extracted with Trizol. Unirradiated cells were used as a control. RNAs were transcripted into cDNA by reverse transcription and labelled with cy5-dCTP and cy3-dCTP respectively. A human genome oligonucleotide set consisting of 5 amino acid-modified 70-mer probes and representing 21,329 well-characterized Homo sapiens genes was selected for microarray analysis and printed on amino-silaned glass slides. Arrays were fabricated using an OmniGrid microarrayer. Only genes whose alteration tendency was consistent in both microarrays were selected as differentially expressed genes. The Affymetrix's short oligonucleotide (25-mer) HG U133A 2.0 array analyses were performed per the manufacturer's instructions. Results Of the 21,329 genes tested, 37 genes showed changes in expression level with ratio higher than 2.0 and lower than 0.5 at 6hrs after irradiation. There were 19 genes showing up-regulation in radiated L02 cells, whereas 18 genes showing down-regulation; At 24hrs after irradiation, 269 genes showed changes in expression level with ratio higher than 2.0 and lower than 0.5. There were 67 genes showing up-regulation in radiated L02 cells, whereas 202 genes showing down

  8. In Utero Bisphenol A Concentration, Metabolism, and Global DNA Methylation Across Matched Placenta, Kidney, and Liver in the Human Fetus

    PubMed Central

    Nahar, Muna S.; Liao, Chunyang; Kannan, Kurunthachalam; Harris, Craig; Dolinoy, Dana C.

    2014-01-01

    While urine has been an easily accessible and feasible matrix for human biomonitoring, analytical measurements in internal tissues and organs can provide more accurate exposure assessments to understand disease etiology. This is especially important for the endocrine active compound, bisphenol A (BPA), where studies investigating internal doses at sensitive periods of human development are currently lacking. Herein, BPA concentrations, BPA-specific metabolizing enzyme gene expression, and global DNA methylation were characterized across three matched tissues from elective pregnancy terminations of 2nd trimester human fetuses: the placenta, liver, and kidney (N=12 each; N=36 total). Compared to liver (free: 0.54-50.5 ng/g), BPA concentrations were lower in matched placenta (<0.05-25.4 ng/g) and kidney (0.08-11.1 ng/g) specimens. BPA-specific metabolism gene expression of GUSB, UGT2B15, STS, and SULT1A1 differed across each tissue type; however, conjugation and deconjugation expression patterns were similar across the fetus. Average LINE1 and CCGG global methylation were 58.3 and 59.2% in placenta, 79.5 and 66.4% in fetal liver, and 77.9 and 77.0% in fetal kidney, with significant tissue-specific DNA methylation differences in both LINE1 (p-value <0.001) and CCGG content (p-value <0.001). Total BPA concentrations were positively associated with global methylation for the placenta only using the LINE1 assay (p-value: 0.002), suggesting organ-specific biological effects after fetal exposure. Utilizing sensitive human clinical specimens, results are informative for BPA toxicokinetics and toxicodynamics assessment in the developing human fetus. PMID:25434263

  9. Anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway.

    PubMed

    Zhao, Xiangqian; Jiang, Kai; Liang, Bin; Huang, Xiaoqiang

    2016-02-01

    Xanthohumol may prevent and cure diabetes and atherosis, have oxidation resistance and antiviral function as well as anticancer effect preventing cancer cell metastasis. We investigate whether the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway. Human liver cancer HepG2 cell were treated with 10, 20, 30 and 40 µM xanthohumol for 48 h. The present study showed that the anticancer effect of xanthohumol was effective in inhibiting proliferation and inducing apoptosis of human liver cancer HepG2 cells. Furthermore, the caspase-3 activity of human liver cancer HepG2 cells was increased by xanthohumol. In addition, 48-h treatment with xanthohumol suppressed NF-κB expression and promoted p53, cleaved PARP, AIF and cytochrome c expression and downregulated XIAP and Bcl-2/Bax expression in human liver cancer HepG2 cells. Therefore, the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through the NF-κB/p53-apoptosis signaling pathway. PMID:26718026

  10. Identification of cytochrome P450 isoform involved in the metabolism of YM992, a novel selective serotonin re-uptake inhibitor, in human liver microsomes.

    PubMed

    Noguchi, K; Mera, A; Watanabe, T; Higuchi, S; Chiba, K

    2000-05-01

    1. In vitro studies were conducted to identify the hepatic cytochrome P450 isoform involved in the metabolism of YM992, ((S)-2-[[(fluoro-4-indanyl)oxy]methyl]morpholine monohydrochloride), a novel serotonin re-uptake inhibitor, in human liver microsomes. 2. Microsomes prepared from yeast expressing CYP1A1, CYP1A2 and CYP2D6 effectively metabolized YM992. A significant correlation was observed between the rate of YM992 metabolism and 7-ethoxyresorufin O-deethylation, CYP1A1/2 specific activity, in liver microsomes from 16 individual donors (r2 = 0.628, p < 0.001). Alpha-naphtoflavone and isosafrole, CYP1A1/2 inhibitors, suppressed the metabolism of YM992 in human liver microsomes in a concentration-dependent manner. 3. The metabolism of YM992 in human liver microsomes was inhibited by approximately 95% by antibodies which recognize both CYP1A1 and CYP1A2 whereas antibodies specific for CYP1A1 did not show inhibitory effects. 4. The same major metabolites, M6 and M7, were generated from YM992 after incubation with human liver microsomes and recombinant human CYP1A2. 5. These results suggest that the metabolism of YM992 in human liver microsomes is mainly catalysed by CYP1A2, and that YM992 might increase plasma concentration of concomitant drugs metabolized by CYP1A2 due to competitive inhibition.

  11. Anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway

    PubMed Central

    ZHAO, XIANGQIAN; JIANG, KAI; LIANG, BIN; HUANG, XIAOQIANG

    2016-01-01

    Xanthohumol may prevent and cure diabetes and atherosis, have oxidation resistance and antiviral function as well as anticancer effect preventing cancer cell metastasis. We investigate whether the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway. Human liver cancer HepG2 cell were treated with 10, 20, 30 and 40 µM xanthohumol for 48 h. The present study showed that the anticancer effect of xanthohumol was effective in inhibiting proliferation and inducing apoptosis of human liver cancer HepG2 cells. Furthermore, the caspase-3 activity of human liver cancer HepG2 cells was increased by xanthohumol. In addition, 48-h treatment with xanthohumol suppressed NF-κB expression and promoted p53, cleaved PARP, AIF and cytochrome c expression and downregulated XIAP and Bcl-2/Bax expression in human liver cancer HepG2 cells. Therefore, the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through the NF-κB/p53-apoptosis signaling pathway. PMID:26718026

  12. Human Parvovirus B19 NS1 Protein Aggravates Liver Injury in NZB/W F1 Mice

    PubMed Central

    Tsai, Chun-Chou; Chiu, Chun-Ching; Hsu, Jeng-Dong; Hsu, Huai-Sheng; Tzang, Bor-Show; Hsu, Tsai-Ching

    2013-01-01

    Human parvovirus B19 (B19) has been associated with a variety of diseases. However, the influence of B19 viral proteins on hepatic injury in SLE is still obscure. To elucidate the effects of B19 viral proteins on livers in SLE, recombinant B19 NS1, VP1u or VP2 proteins were injected subcutaneously into NZB/W F1 mice, respectively. Significant expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected in NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Markedly hepatocyte disarray and lymphocyte infiltration were observed in livers from NZB/WF 1 mice receiving B19 NS1 as compared to those mice receiving PBS. Additionally, significant increases of Tumor Necrosis Factor –α (TNF-α), TNF-α receptor, IκB kinase –α (IKK-α), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor (IκB) and nuclear factor-kappa B (NF-κB) were detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Accordingly, significant increases of matrix metalloproteinase-9 (MMP9) and U-plasminogen activator (uPA) were also detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Contrarily, no significant variation on livers from NZB/W F1 mice receiving B19 VP1u or VP2 was observed as compared to those mice receiving PBS. These findings firstly demonstrated the aggravated effects of B19 NS1 but not VP1u or VP2 protein on hepatic injury and provide a clue in understanding the role of B19 NS1 on hepatic injury in SLE. PMID:23555760

  13. Human parvovirus B19 NS1 protein aggravates liver injury in NZB/W F1 mice.

    PubMed

    Tsai, Chun-Chou; Chiu, Chun-Ching; Hsu, Jeng-Dong; Hsu, Huai-Sheng; Tzang, Bor-Show; Hsu, Tsai-Ching

    2013-01-01

    Human parvovirus B19 (B19) has been associated with a variety of diseases. However, the influence of B19 viral proteins on hepatic injury in SLE is still obscure. To elucidate the effects of B19 viral proteins on livers in SLE, recombinant B19 NS1, VP1u or VP2 proteins were injected subcutaneously into NZB/W F1 mice, respectively. Significant expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected in NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Markedly hepatocyte disarray and lymphocyte infiltration were observed in livers from NZB/WF 1 mice receiving B19 NS1 as compared to those mice receiving PBS. Additionally, significant increases of Tumor Necrosis Factor -α (TNF-α), TNF-α receptor, IκB kinase -α (IKK-α), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor (IκB) and nuclear factor-kappa B (NF-κB) were detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Accordingly, significant increases of matrix metalloproteinase-9 (MMP9) and U-plasminogen activator (uPA) were also detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Contrarily, no significant variation on livers from NZB/W F1 mice receiving B19 VP1u or VP2 was observed as compared to those mice receiving PBS. These findings firstly demonstrated the aggravated effects of B19 NS1 but not VP1u or VP2 protein on hepatic injury and provide a clue in understanding the role of B19 NS1 on hepatic injury in SLE.

  14. Fast macromolecular proton fraction mapping of the human liver in vivo for quantitative assessment of hepatic fibrosis.

    PubMed

    Yarnykh, Vasily L; Tartaglione, Erica V; Ioannou, George N

    2015-12-01

    The macromolecular proton fraction (MPF) is a quantitative MRI parameter determining the magnetization transfer (MT) effect in tissues, and is defined as the relative amount of immobile macromolecular protons involved in magnetization exchange with mobile water protons. MPF has the potential to provide a quantitative assessment of fibrous tissue because of the intrinsically high MPF specific for collagen. The goal of this study was to investigate the relationship between histologically determined fibrosis stage and MPF in the liver parenchyma measured using a recently developed fast single-point clinically targeted MPF mapping method. Optimal saturation parameters for single-point liver MPF measurements were determined from the analysis of liver Z spectra in vivo based on the error propagation model. Sixteen patients with chronic hepatitis C viral infection underwent 3-T MRI using an optimized liver MPF mapping protocol. Fourteen patients had prior liver biopsy with histologically staged fibrosis (METAVIR scores F0-F3) and two patients had clinically diagnosed cirrhosis (score F4 was assigned). The protocol included four breath-hold three-dimensional scans with 2 × 3 × 6-mm(3) resolution and 10 transverse sections: dynamic acquisition of MT-weighted and reference images; dynamic acquisition of three images for variable flip angle T1 mapping; dual-echo B0 map; and actual flip angle imaging B1 map. The average liver MPF was determined as the mode of the MPF histograms. MPF was significantly increased in patients with clinically significant fibrosis (scores F2-F4, n = 6) relative to patients with no or mild fibrosis (scores F0-F1, n = 10): 6.49 ± 0.36% versus 5.94 ± 0.26%, p < 0.01 (Mann-Whitney test). MPF and fibrosis scores were strongly positively correlated, with a Spearman's rank correlation coefficient of 0.80 (p < 0.001). This study demonstrates the feasibility of fast MPF mapping of the human liver in vivo and confirms the

  15. Cryopreserved hepatic progenitor cells derived from human embryonic stem cells can arrest progression of liver fibrosis in rats.

    PubMed

    Mandal, Arundhati; Raju, Sheena; Viswanathan, Chandra

    2016-10-01

    Hepatocytes generated from human embryonic stem cells (hESCs) are considered to be an excellent candidate for restoring the liver function deficiencies. We have earlier standardized a three-step differentiation protocol to generate functional hepatocyte-like cells (HLCs) from hESCs, which expressed the major hepatic markers. We have also found that the HLCs remain stable and functional even after extended period of in vitro culture and cryopreservation. In the present study, we have aimed to investigate the therapeutic potential of cryopreserved-thawed hESC-derived hepatic progenitor cells following transplantation in carbon tetrachloride-induced fibrotic rat livers. Significant therapeutic effects, including improved hepatic histology and normal serum biochemistry of hepatic enzymes along with increased survival rate, were observed in the cell transplanted rats. This result is an encouraging indication to develop methods for clinical application of hESC-derived hepatic lineage cells.

  16. 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 th