Effect of adoptive transfer or depletion of regulatory T cells on triptolide-induced liver injury

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Xinzhi eWang

2016-04-01

Full Text Available ObjectiveThe aim of this study is to clarify the role of regulatory T cell (Treg in triptolide (TP-induced hepatotoxicity. MethodsFemale C57BL/6 mice received either adoptive transfer of Tregs or depletion of Tregs, then underwent TP administration and were sacrificed 24 hours after TP administration. Liver injury was determined according to ALT and AST levels in serum and histopathological change in liver tissue. Hepatic frequencies of Treg cells and the mRNA expression levles of transcription factor FoxP3 and RORγt, IL-10, SOCS and Notch/Notch ligand were investigated.ResultsDuring TP-induced liver injury, hepatic Treg and IL-10 decreased, while Th17 cell transcription factor RORγt, SOCS signaling and Notch signaling increased, accompanied with liver inflammation. Adoptive transfer of Tregs ameliorated the severity of TP-induced liver injury, accompanied with increased levels of hepatic Treg and IL-10. Adoptive transfer of Tregs remarkably inhibited the expression of RORγt, SOCS3, Notch1 and Notch3. On the contrary, depletion of Treg cells in TP-administered mice resulted in a notable increase of RORγt, SOCS1, SOCS3 and Notch3, while the Treg and IL-10 of liver decreased. Consistent with the exacerbation of liver injury, higher serum levels of ALT and AST were detected in Treg-depleted mice. ConclusionsThese results showed that adoptive transfer or depletion of Tregs attenuated or aggravated TP-induced liver injury, suggesting that Tregs could play important roles in the progression of liver injury. SOCS proteins and Notch signaling affected Tregs, which may contribute to the pathogenesis of TP-induced hepatotoxicity.

Characterization of genetically engineered mouse hepatoma cells with inducible liver functions by overexpression of liver-enriched transcription factors.

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Yamamoto, Hideaki; Tonello, Jane Marie; Sambuichi, Takanori; Kawabe, Yoshinori; Ito, Akira; Kamihira, Masamichi

2018-01-01

New cell sources for the research and therapy of organ failure could significantly alleviate the shortage of donor livers that are available to patients who suffer from liver disease. Liver carcinoma derived cells, or hepatoma cells, are the ideal cells for developing bioartificial liver systems. Such cancerous liver cells are easy to prepare in large quantities and can be maintained over long periods under standard culture conditions, unlike primary hepatocytes. However, hepatoma cells possess only a fraction of the functions of primary hepatocytes. In a previous study, by transducing cells with liver-enriched transcription factors that could be inducibly overexpressed-hepatocyte nuclear factor (HNF)1α, HNF1β, HNF3β [FOXA2], HNF4α, HNF6, CCAAT/enhancer binding protein (C/EBP)α, C/EBPβ and C/EBPγ-we created mouse hepatoma cells with high liver-specific gene expression called the Hepa/8F5 cell line. In the present study, we performed functional and genetic analyses to characterize the Hepa/8F5 cell line. Further, in three-dimensional cultures, the function of these cells improved significantly compared to parental cells. Ultimately, these cells might become a new resource that can be used in basic and applied hepatic research. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

SET mediates TCE-induced liver cell apoptosis through dephosphorylation and upregulation of nucleolin.

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Ren, Xiaohu; Huang, Xinfeng; Yang, Xifei; Liu, Yungang; Liu, Wei; Huang, Haiyan; Wu, Desheng; Zou, Fei; Liu, Jianjun

2017-06-20

Trichloroethylene (TCE) is an occupational and environmental chemical that can cause severe hepatotoxicity. While our previous studies showed that the phosphatase inhibitor SET is a key mediator of TCE-induced liver cell apoptosis, the molecular mechanisms remain elusive. Using quantitative phosphoproteomic analysis, we report here that nucleolin is a SET-regulated phosphoprotein in human liver HL-7702 cells. Functional analysis suggested that SET promoted dephosphorylation of nucleolin, decreased its binding to its transcriptional activator, c-myc, and upregulated nucleolin expression in TCE-treated cells. Importantly, TCE-induced hepatocyte apoptosis was significantly attenuated when nucleolin was downregulated with specific siRNAs. These findings indicate that TCE may induce hepatocyte apoptosis via SET-mediated dephosphorylation and overexpression of nucleolin.

Hypercholesterolemia Induces Differentiation of Regulatory T Cells in the Liver.

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Mailer, Reiner K W; Gisterå, Anton; Polyzos, Konstantinos A; Ketelhuth, Daniel F J; Hansson, Göran K

2017-05-26

The liver is the central organ that responds to dietary cholesterol intake and facilitates the release and clearance of lipoprotein particles. Persistent hypercholesterolemia leads to immune responses against lipoprotein particles that drive atherosclerosis. However, the effect of hypercholesterolemia on hepatic T-cell differentiation remains unknown. To investigate hepatic T-cell subsets upon hypercholesterolemia. We observed that hypercholesterolemia elevated the intrahepatic regulatory T (Treg) cell population and increased the expression of transforming growth factor-β1 in the liver. Adoptive transfer experiments revealed that intrahepatically differentiated Treg cells relocated to the inflamed aorta in atherosclerosis-prone low-density lipoprotein receptor deficient ( Ldlr -/- ) mice. Moreover, hypercholesterolemia induced the differentiation of intrahepatic, but not intrasplenic, Th17 cells in wild-type mice, whereas the disrupted liver homeostasis in hypercholesterolemic Ldlr -/- mice led to intrahepatic Th1 cell differentiation and CD11b + CD11c + leukocyte accumulation. Our results elucidate a new mechanism that controls intrahepatic T-cell differentiation during atherosclerosis development and indicates that intrahepatically differentiated T cells contribute to the CD4 + T-cell pool in the atherosclerotic aorta. © 2017 American Heart Association, Inc.

Potential and Challenges of Induced Pluripotent Stem Cells in Liver Diseases Treatment

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Yue Yu

2014-09-01

Full Text Available Tens of millions of patients are affected by liver disease worldwide. Many of these patients can benefit from cell therapy involving living metabolically active cells, either by treatment of their liver disease, or by prevention of their disease phenotype. Cell therapies, including hepatocyte transplantation and bioartificial liver (BAL devices, have been proposed as therapeutic alternatives to the shortage of transplantable livers. Both BAL and hepatocyte transplantation are cellular therapies that avoid use of a whole liver. Hepatocytes are also widely used in drug screening and liver disease modelling. However, the demand for human hepatocytes, heavily outweighs their availability by conventional means. Induced pluripotent stem cells (iPSCs technology brings together the potential benefits of embryonic stem cells (ESCs (i.e., self-renewal, pluripotency and addresses the major ethical and scientific concerns of ESCs: embryo destruction and immune-incompatibility. It has been shown that hepatocyte-like cells (HLCs can be generated from iPSCs. Furthermore, human iPSCs (hiPSCs can provide an unlimited source of human hepatocytes and hold great promise for applications in regenerative medicine, drug screening and liver diseases modelling. Despite steady progress, there are still several major obstacles that need to be overcome before iPSCs will reach the bedside. This review will focus on the current state of efforts to derive hiPSCs for potential use in modelling and treatment of liver disease.

Inhibitory Effects of Verrucarin A on Tunicamycin-Induced ER Stress in FaO Rat Liver Cells

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Eun Young Bae

2015-05-01

Full Text Available Endoplasmic reticulum (ER stress is linked with development and maintenance of cancer, and serves as a therapeutic target for treatment of cancer. Verrucarin A, isolated from the broth of Fusarium sp. F060190, showed potential inhibitory activity on tunicamycin-induced ER stress in FaO rat liver cells. In addition, the compound decreased tunicamycin-induced GRP78 promoter activity in a dose dependent manner without inducing significant inhibition of luciferase activity and cell growth for 6 and 12 h. Moreover, the compound decreased the expression of GRP78, CHOP, XBP-1, and suppressed XBP-1, and reduced phosphorylation of IRE1α in FaO rat liver cells. This evidence suggests for the first time that verrucarin A inhibited tunicamycin-induced ER stress in FaO rat liver cells.

The spleen as an extramedullary source of inflammatory cells responding to acetaminophen-induced liver injury

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Mandal, Mili; Gardner, Carol R.; Sun, Richard; Choi, Hyejeong; Lad, Sonali; Mishin, Vladimir; Laskin, Jeffrey D.; Laskin, Debra L.

2016-01-01

Macrophages have been shown to play a role in acetaminophen (APAP)-induced hepatotoxicity, contributing to both pro- and anti-inflammatory processes. In these studies, we analyzed the role of the spleen as an extramedullary source of hepatic macrophages. APAP administration (300 mg/kg, i.p.) to control mice resulted in an increase in CD11b + infiltrating Ly6G + granulocytic and Ly6G − monocytic cells in the spleen and the liver. The majority of the Ly6G + cells were also positive for the monocyte/macrophage activation marker, Ly6C, suggesting a myeloid derived suppressor cell (MDSC) phenotype. By comparison, Ly6G − cells consisted of 3 subpopulations expressing high, intermediate, and low levels of Ly6C. Splenectomy was associated with increases in mature (F4/80 + ) and immature (F4/80 − ) pro-inflammatory Ly6C hi macrophages and mature anti-inflammatory (Ly6C lo ) macrophages in the liver after APAP; increases in MDSCs were also noted in the livers of splenectomized (SPX) mice after APAP. This was associated with increases in APAP-induced expression of chemokine receptors regulating pro-inflammatory (CCR2) and anti-inflammatory (CX3CR1) macrophage trafficking. In contrast, APAP-induced increases in pro-inflammatory galectin-3 + macrophages were blunted in livers of SPX mice relative to control mice, along with hepatic expression of TNF-α, as well as the anti-inflammatory macrophage markers, FIZZ-1 and YM-1. These data demonstrate that multiple subpopulations of pro- and anti-inflammatory cells respond to APAP-induced injury, and that these cells originate from distinct hematopoietic reservoirs. - Highlights: • Multiple inflammatory cell subpopulations accumulate in the spleen and liver following acetaminophen (APAP) intoxication. • Splenectomy alters liver inflammatory cell populations responding to APAP. • Inflammatory cells accumulating in the liver in response to APAP originate from the spleen and the bone marrow. • Hepatotoxicity is reduced in

The spleen as an extramedullary source of inflammatory cells responding to acetaminophen-induced liver injury

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Mandal, Mili, E-mail: milimandal@gmail.com [Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854 (United States); Gardner, Carol R., E-mail: cgardner@pharmacy.rutgers.edu [Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854 (United States); Sun, Richard, E-mail: fishpower52@gmail.com [Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854 (United States); Choi, Hyejeong, E-mail: choi@eohsi.rutgers.edu [Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854 (United States); Lad, Sonali, E-mail: sonurose92@gmail.com [Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854 (United States); Mishin, Vladimir, E-mail: mishinv@eohsi.rutgers.edu [Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854 (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.edu [Department of Environmental and Occupational Health, School of Public Health, Rutgers University, Piscataway, NJ 08854 (United States); Laskin, Debra L., E-mail: laskin@eohsi.rutgers.edu [Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854 (United States)

2016-08-01

Macrophages have been shown to play a role in acetaminophen (APAP)-induced hepatotoxicity, contributing to both pro- and anti-inflammatory processes. In these studies, we analyzed the role of the spleen as an extramedullary source of hepatic macrophages. APAP administration (300 mg/kg, i.p.) to control mice resulted in an increase in CD11b{sup +} infiltrating Ly6G{sup +} granulocytic and Ly6G{sup −} monocytic cells in the spleen and the liver. The majority of the Ly6G{sup +} cells were also positive for the monocyte/macrophage activation marker, Ly6C, suggesting a myeloid derived suppressor cell (MDSC) phenotype. By comparison, Ly6G{sup −} cells consisted of 3 subpopulations expressing high, intermediate, and low levels of Ly6C. Splenectomy was associated with increases in mature (F4/80{sup +}) and immature (F4/80{sup −}) pro-inflammatory Ly6C{sup hi} macrophages and mature anti-inflammatory (Ly6C{sup lo}) macrophages in the liver after APAP; increases in MDSCs were also noted in the livers of splenectomized (SPX) mice after APAP. This was associated with increases in APAP-induced expression of chemokine receptors regulating pro-inflammatory (CCR2) and anti-inflammatory (CX3CR1) macrophage trafficking. In contrast, APAP-induced increases in pro-inflammatory galectin-3{sup +} macrophages were blunted in livers of SPX mice relative to control mice, along with hepatic expression of TNF-α, as well as the anti-inflammatory macrophage markers, FIZZ-1 and YM-1. These data demonstrate that multiple subpopulations of pro- and anti-inflammatory cells respond to APAP-induced injury, and that these cells originate from distinct hematopoietic reservoirs. - Highlights: • Multiple inflammatory cell subpopulations accumulate in the spleen and liver following acetaminophen (APAP) intoxication. • Splenectomy alters liver inflammatory cell populations responding to APAP. • Inflammatory cells accumulating in the liver in response to APAP originate from the spleen and the

Mangosteen peel extract reduces formalin-induced liver cell death in rats

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Afiana Rohmani

2014-08-01

Full Text Available Background Formalin is a xenobiotic that is now commonly used as a preservative in the food industry. The liver is an organ that has the highest metabolic capacity as compared to other organs. Mangosteen or Garcinia mangostana Linn (GML peel contains xanthones, which are a source of natural antioxidants. The purpose of this study was to evaluate the effect of mangosteen peel extract on formalin-induced liver cell mortality rate and p53 protein expression in Wistar rats. Methods Eighteen rats received formalin orally for 2 weeks, and were subsequently divided into 3 groups, consisting of the formalin-control group receiving a placebo and treatment groups 1 and 2, which were treated with mangosteen peel extract at doses of 200 and 400 mg/kgBW/day, respectively. The treatment was carried out for 1 week, and finally the rats were terminated. The differences in liver cell mortality rate and p53 protein expression were analyzed. Results One-way ANOVA analysis showed significant differences in liver cell mortality rate among the three groups (p=0.004. The liver cell mortality rate in the treatment group receiving 400 mg/kgBW/day extract was lower than that in the formalin-control group. There was no p53 expression in all groups. Conclusions Garcinia mangostana Linn peel extract reduced the mortality rate of liver cells in rats receiving oral formalin. Involvement of p53 expression in liver cell mortality in rats exposed to oral formalin is presumably negligible.

Liver sinusoidal endothelial cells induce immunosuppressive IL-10-producing Th1 cells via the Notch pathway.

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Neumann, Katrin; Rudolph, Christine; Neumann, Christian; Janke, Marko; Amsen, Derk; Scheffold, Alexander

2015-07-01

Under homeostasis, liver sinusoidal endothelial cells (LSECs) shift intrahepatic T-cell responses towards tolerance. However, the role of LSECs in the regulation of T-cell-induced liver inflammation is less clear. Here, we studied the capacity of LSECs to modulate pro-inflammatory Th1-cell differentiation in mice. Using in vitro co-culture systems and subsequent cytokine analysis, we showed that LSECs induced high amounts of the anti-inflammatory cytokine IL-10 in developing Th1 cells. These LSEC-stimulated Th1 cells had no pro-inflammatory capacity in vivo but instead actively suppressed an inflammatory Th1-cell-induced delayed-type hypersensitivity reaction. Blockage of IL-10 signaling in vivo inhibited immunosuppressive activity of LSEC-stimulated Th1 cells. We identified the Notch pathway as a mechanism how LSECs trigger IL-10 expression in Th1 cells. LSECs expressed high levels of the Delta-like and Jagged family of Notch ligands and induced expression of the Notch target genes hes-1 and deltex-1 in Th1 cells. Blockade of Notch signaling selectively inhibited IL-10 induction in Th1 cells by LSECs. Our findings suggest that LSEC-induced IL-10 expression in Th1 cells via the Notch pathway may contribute to the control of hepatic inflammatory immune responses by induction of a self-regulatory mechanism in pro-inflammatory Th1 cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Human endometrial regenerative cells alleviate carbon tetrachloride-induced acute liver injury in mice

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Shanzheng Lu

2016-10-01

Full Text Available Abstract Background The endometrial regenerative cell (ERC is a novel type of adult mesenchymal stem cell isolated from menstrual blood. Previous studies demonstrated that ERCs possess unique immunoregulatory properties in vitro and in vivo, as well as the ability to differentiate into functional hepatocyte-like cells. For these reasons, the present study was undertaken to explore the effects of ERCs on carbon tetrachloride (CCl4–induced acute liver injury (ALI. Methods An ALI model in C57BL/6 mice was induced by administration of intraperitoneal injection of CCl4. Transplanted ERCs were intravenously injected (1 million/mouse into mice 30 min after ALI induction. Liver function, pathological and immunohistological changes, cell tracking, immune cell populations and cytokine profiles were assessed 24 h after the CCl4 induction. Results ERC treatment effectively decreased the CCl4-induced elevation of serum alanine aminotransferase (ALT and aspartate aminotransferase (AST activities and improved hepatic histopathological abnormalities compared to the untreated ALI group. Immunohistochemical staining showed that over-expression of lymphocyte antigen 6 complex, locus G (Ly6G was markedly inhibited, whereas expression of proliferating cell nuclear antigen (PCNA was increased after ERC treatment. Furthermore, the frequency of CD4+ and CD8+ T cell populations in the spleen was significantly down-regulated, while the percentage of splenic CD4+CD25+FOXP3+ regulatory T cells (Tregs was obviously up-regulated after ERC treatment. Moreover, splenic dendritic cells in ERC-treated mice exhibited dramatically decreased MHC-II expression. Cell tracking studies showed that transplanted PKH26-labeled ERCs engrafted to lung, spleen and injured liver. Compared to untreated controls, mice treated with ERCs had lower levels of IL-1β, IL-6, and TNF-α but higher level of IL-10 in both serum and liver. Conclusions Human ERCs protect the liver from acute injury

Alleviation of lipopolysaccharide/d-galactosamine-induced liver injury in leukocyte cell-derived chemotaxin 2 deficient mice

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Akinori Okumura

2017-12-01

Full Text Available Leukocyte cell-derived chemotaxin 2 (LECT2 is a secreted pleiotropic protein that is mainly produced by the liver. We have previously shown that LECT2 plays an important role in the pathogenesis of inflammatory liver diseases. Lipopolysaccharide/d-galactosamine (LPS/d-GalN-induced acute liver injury is a known animal model of fulminant hepatic failure. Here we found that this hepatic injury was alleviated in LECT2-deficient mice. The levels of TNF-α and IFN-γ, which mediate this hepatitis, had significantly decreased in these mice, with the decrease in IFN-γ production notably greater than that in TNF-α. We therefore analyzed IFN-γ-producing cells in liver mononuclear cells. Flow cytometric analysis showed significantly reduced IFN-γ production in hepatic NK and NKT cells in LECT2-deficient mice compared with in wild-type mice. We also demonstrated a decrease in IFN-γ production in LECT2-deficient mice after systemic administration of recombinant IL-12, which is known to induce IFN-γ in NK and NKT cells. These results indicate that a decrease of IFN-γ production in NK and NKT cells was involved in the alleviation of LPS/d-GalN-induced liver injury in LECT2-deficient mice.

Drug-Induced Liver Injury: Cascade of Events Leading to Cell Death, Apoptosis or Necrosis

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Andrea Iorga

2017-05-01

Full Text Available Drug-induced liver injury (DILI can broadly be divided into predictable and dose dependent such as acetaminophen (APAP and unpredictable or idiosyncratic DILI (IDILI. Liver injury from drug hepatotoxicity (whether idiosyncratic or predictable results in hepatocyte cell death and inflammation. The cascade of events leading to DILI and the cell death subroutine (apoptosis or necrosis of the cell depend largely on the culprit drug. Direct toxins to hepatocytes likely induce oxidative organelle stress (such as endoplasmic reticulum (ER and mitochondrial stress leading to necrosis or apoptosis, while cell death in idiosyncratic DILI (IDILI is usually the result of engagement of the innate and adaptive immune system (likely apoptotic, involving death receptors (DR. Here, we review the hepatocyte cell death pathways both in direct hepatotoxicity such as in APAP DILI as well as in IDILI. We examine the known signaling pathways in APAP toxicity, a model of necrotic liver cell death. We also explore what is known about the genetic basis of IDILI and the molecular pathways leading to immune activation and how these events can trigger hepatotoxicity and cell death.

Cellular Mechanisms of Liver Regeneration and Cell-Based Therapies of Liver Diseases

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Irina V. Kholodenko

2017-01-01

Full Text Available The emerging field of regenerative medicine offers innovative methods of cell therapy and tissue/organ engineering as a novel approach to liver disease treatment. The ultimate scientific foundation of both cell therapy of liver diseases and liver tissue and organ engineering is delivered by the in-depth studies of the cellular and molecular mechanisms of liver regeneration. The cellular mechanisms of the homeostatic and injury-induced liver regeneration are unique. Restoration of the mass of liver parenchyma is achieved by compensatory hypertrophy and hyperplasia of the differentiated parenchymal cells, hepatocytes, while expansion and differentiation of the resident stem/progenitor cells play a minor or negligible role. Participation of blood-borne cells of the bone marrow origin in liver parenchyma regeneration has been proven but does not exceed 1-2% of newly formed hepatocytes. Liver regeneration is activated spontaneously after injury and can be further stimulated by cell therapy with hepatocytes, hematopoietic stem cells, or mesenchymal stem cells. Further studies aimed at improving the outcomes of cell therapy of liver diseases are underway. In case of liver failure, transplantation of engineered liver can become the best option in the foreseeable future. Engineering of a transplantable liver or its major part is an enormous challenge, but rapid progress in induced pluripotency, tissue engineering, and bioprinting research shows that it may be doable.

Nuclear receptor CAR (NR1I3) is essential for DDC-induced liver injury and oval cell proliferation in mouse liver.

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Yamazaki, Yuichi; Moore, Rick; Negishi, Masahiko

2011-11-01

The liver is endowed with the ability to regenerate hepatocytes in response to injury. When this regeneration ability is impaired during liver injury, oval cells, which are considered to be postnatal hepatic progenitors, proliferate and differentiate into hepatocytes. Here we have demonstrated that 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) activates the nuclear receptor constitutive active/androstane receptor (CAR), resulting in proliferation of oval cells in mouse liver. Activation of CAR by DDC was shown by hepatic nuclear CAR accumulation and cytochrome P450 (CYP)2B10 mRNA induction after feeding a 0.1% DDC-containing diet to Car(+/+) mice. After being fed the DDC diet, Car(+/+), but not Car(-/-) mice, developed severe liver injury and an A6 antibody-stained ductular reaction in an area around the portal tract. Oval cell proliferation was confirmed by laser capture microdissection and real-time PCR; mRNAs for the two oval cell markers epithelial cell adhesion molecule and TROP2 were specifically induced in the periportal region of DDC diet-fed Car(+/+), but not Car(-/-) mice. Although rates of both hepatocyte growth and death were initially enhanced only in DDC diet-fed Car(+/+) mice, growth was attenuated when oval cells proliferated, whereas death continued unabated. DDC-induced liver injury, which differs from other CAR activators such as phenobarbital, occurred in the periportal region where cells developed hypertrophy, accumulated porphyrin crystals and inflammation developed, all in association with the proliferation of oval cells. Thus, CAR provides an excellent experimental model for further investigations into its roles in liver regeneration, as well as the development of diseases such as hepatocellular carcinoma.

Liver-cell patterning lab chip: mimicking the morphology of liver lobule tissue.

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Ho, Chen-Ta; Lin, Ruei-Zeng; Chen, Rong-Jhe; Chin, Chung-Kuang; Gong, Song-En; Chang, Hwan-You; Peng, Hwei-Ling; Hsu, Long; Yew, Tri-Rung; Chang, Shau-Feng; Liu, Cheng-Hsien

2013-09-21

A lobule-mimetic cell-patterning technique for on-chip reconstruction of centimetre-scale liver tissue of heterogeneous hepatic and endothelial cells via an enhanced field-induced dielectrophoresis (DEP) trap is demonstrated and reported. By mimicking the basic morphology of liver tissue, the classic hepatic lobule, the lobule-mimetic-stellate-electrodes array was designed for cell patterning. Through DEP manipulation, well-defined and enhanced spatial electric field gradients were created for in-parallel manipulation of massive individual cells. With this liver-cell patterning labchip design, the original randomly distributed hepatic and endothelial cells inside the microfluidic chamber can be manipulated separately and aligned into the desired pattern that mimicks the morphology of liver lobule tissue. Experimental results showed that both hepatic and endothelial cells were orderly guided, snared, and aligned along the field-induced orientation to form the lobule-mimetic pattern. About 95% cell viability of hepatic and endothelial cells was also observed after cell-patterning demonstration via a fluorescent assay technique. The liver function of CYP450-1A1 enzyme activity showed an 80% enhancement for our engineered liver tissue (HepG2+HUVECs) compared to the non-patterned pure HepG2 for two-day culturing.

Study on bone marrow mesenchymal stem cells in repairing of radiation induced acute liver injury of rats

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Bao Yongxing; Lou Fan; Zhao Huarong; Zhu Huhu; Ma Yan; Wen Hao

2010-01-01

Objective: To investigate the role of mesenchymal stem cells in the repair of radiation induced liver injury. Methods: 12 female SD rats were irradiated with 20 Gy 6 MV X-rays on the right lobe of the liver, to establish the model of radiation induced liver injury. The rats were divided randomly into two groups as invention group and control group, and transplanted with 1 ml male mesenchymal suspension or 1 ml normal saline in 4 hours after radiotherapy. The morphological changes of liver were observed. The existence of sex determining gene Y(SRY) and the level of alpha-smooth muscle actin (a-SMA) were detected. Results: Some injury of right lobe liver in two groups were observed, and the injury degree of right lobe liver in intervention group were lower than that of control group. The amount of SRY positive cells in the right lobe liver of intervention group was higher than that in the left lobe liver (t = 3.77, P <0.05). The positive expression rate of a-SMA in right lobe liver of intervention group was lower than that of control group. Conclusions: Acute radiation induced liver injury could lead BMSCs' homing in order to decrease the degree of liver fibrosis. (authors)

LP-THAE induced tumor cell apoptosis of rabbit VX2 liver carcinoma

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Chen Shengli; Quan Yi; Huang Zicheng; Chen Guodong; Zhu Dongliang

2007-01-01

Objective: To research tumor cell apoptosis induced by Lp-THAE of rabbit VX2 liver implanted tumor. Methods: 27 New Zealand white rabbits implanted with VX2 tumor at left middle lobe of the liver divided into three groups: Group A(n= 9) Lp-THAE: treated through transhepatic artery catheterization; Group B(n=9) THAI and Group C(n=9) as control. The rabbits were executed at second to fifth day after treatment. HE dye microscopy was taken for counting the typical apoptosis cells and calculating apoptosis index (ApI). FITC-AnnexinV/PI assay was used for measuring apoptosis by flow cytometry. Results: The ApI of tumor central area and marginal area were (17.769±2.417)%, (4.129±1.172)%, P<0.01. The percentages of tumor cell apoptosis and tumor cell necrosis were (16.483±1.404)%, (9.478±0.964)%, P<0.01 and (43.559±5.053)%, (33.460±1.840)%, P=0.093. The total percentages of tumor cell apoptosis and necrosis were (60.042±13.979)%, (42.938±8.979)%, P< 0.01, at tumor center and marginal area in THAE group respectively. The ApI, percentages of tumor cell apoptosis and necrosis in THAE group were significantly higher than those of THAI group (P<0.01). The percentages of tumor cell apoptosis at tumor center area in THAE group were significantly higher than those of tumor marginal area(P<0.01). Conclusion: Induced tumor cell apoptosis and necrosis are two mechanisms of action for Lp-THAE treatment of liver carcinoma. (authors)

Morin ameliorates chemically induced liver fibrosis in vivo and inhibits stellate cell proliferation in vitro by suppressing Wnt/β-catenin signaling

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MadanKumar, Perumal; NaveenKumar, Perumal; Manikandan, Samidurai [Department of Biochemistry, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India); Devaraj, Halagowder [Department of Zoology, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India); NiranjaliDevaraj, Sivasithamparam, E-mail: niranjali@yahoo.com [Department of Biochemistry, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India)

2014-06-01

The anti-fibrotic effect of morin was examined in LX-2 cells (culture-activated human hepatic stellate cells) and in diethylnitrosamine induced rat model of liver fibrosis. The in vitro study was designed to determine whether morin affects the survival of cultured LX-2 cells, while the in vivo study was designed to evaluate the antioxidant and anti-fibrotic efficacy of morin on diethylnitrosamine induced liver fibrosis in male albino Wistar rat. The activities of liver function enzymes in serum, liver lipid peroxide levels, activities of serum antioxidant enzymes and liver architecture were monitored to cast light on the antioxidant and hepatoprotective nature of morin. To establish the anti-fibrotic effects of morin, the levels of key Wnt signaling molecules which are strongly associated with the signal transduction pathway of HSC activation were measured. Overall, from the in vitro results, it was observed that morin at 50 μM concentration inhibited the proliferation of cultured LX-2 cells, inhibited Wnt signaling and induced G1 cell cycle arrest. The in vivo results further confirmed that morin by downregulating the expressions of GSK-3β, β-catenin and cyclin D1 ameliorated DEN-induced liver fibrosis. Hence morin could be employed as a promising chemopreventive natural supplement for liver fibrosis. - Highlights: • In vivo and in vitro results revealed the active participation of Wnt signaling. • Morin at 50 μM inhibited LX-2 cell proliferation by suppressing Wnt signaling. • Morin exhibited hepatoprotective effects against DEN induced liver fibrosis. • Morin inhibited HSC activation in vivo by downregulating Wnt/β-catenin signaling.

Action of DTPA on hepatic plutonium. II. DTPA-induced removal of monomeric plutonium from mouse liver parenchymal cells

International Nuclear Information System (INIS)

Bhattacharyya, M.H.; Peterson, D.P.; Lindenbaum, A.

1978-01-01

Liver parenchymal cells were isolated 6 and 24 hr following the administration of diethylenetriaminepentaacetic acid (DTPA, 0.25 mmole/kg) to mice previously injected with 239 Pu-citrate (4.4 μCi/kg). Isolated parenchymal cells contained 440 dpm Pu/10 6 cells at 24 hr after Pu injection, just prior to DTPA administration. The PU content decreased to 330 dpm/10 6 cells at 6 hr and 140 dpm/10 6 cells at 24 hr after DTPA administration. Thus DTPA induced a striking decrease in the Pu content of isolated liver parenchymal cells. Parenchymal cells isolated from control mice not treated with DTPA changed little in Pu content from 24 to 48 hr after Pu injection. By 24 hr after DTPA treatment, the decrease in the Pu content of isolated liver parenchymal cells could account for the DTPA-induced release of Pu from the intact liver. Thus in the liver DTPA appears to act preferentially on the Pu associated with parenchymal cells. Liver parenchymal cells isolated 6 hr after DTPA administration and containing 330 dpm Pu/10 6 cells were incubated in vitro in the absence of added DTPA. After 18 hr of incubation the cells contained 130 dpm Pu/10 6 cells. This level corresponds to the level observed in cells isolated 24 hr after DTPA administration. Cells isolated from untreated mice lost only 15% of their Pu content during a similar in vitro incubation. Thus, by 6 hr after DTPA administration to the mouse, isolated liver parenchymal cells appeared to retain their ability to release Pu in vitro with no need for additional exposure to DTPA. The physiological significance of this finding is discussed

Differential effects of ciguatoxin and maitotoxin in primary cultures of cortical neurons.

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Martin, Victor; Vale, Carmen; Antelo, Alvaro; Hirama, Masahiro; Yamashita, Shuji; Vieytes, Mercedes R; Botana, Luis M

2014-08-18

Ciguatoxins (CTXs) and maitotoxins (MTXs) are polyether ladder shaped toxins derived from the dinoflagellate Gambierdiscus toxicus. Despite the fact that MTXs are 3 times larger than CTXs, part of the structure of MTXs resembles that of CTXs. To date, the synthetic ciguatoxin, CTX 3C has been reported to activate voltage-gated sodium channels, whereas the main effect of MTX is inducing calcium influx into the cell leading to cell death. However, there is a lack of information regarding the effects of these toxins in a common cellular model. Here, in order to have an overview of the main effects of these toxins in mice cortical neurons, we examined the effects of MTX and the synthetic ciguatoxin CTX 3C on the main voltage dependent ion channels in neurons, sodium, potassium, and calcium channels as well as on membrane potential, cytosolic calcium concentration ([Ca(2+)]c), intracellular pH (pHi), and neuronal viability. Regarding voltage-gated ion channels, neither CTX 3C nor MTX affected voltage-gated calcium or potassium channels, but while CTX 3C had a large effect on voltage-gated sodium channels (VGSC) by shifting the activation and inactivation curves to more hyperpolarized potentials and decreasing peak sodium channel amplitude, MTX, at 5 nM, had no effect on VGSC activation and inactivation but decreased peak sodium current amplitude. Other major differences between both toxins were the massive calcium influx and intracellular acidification produced by MTX but not by CTX 3C. Indeed, the novel finding that MTX produces acidosis supports a pathway recently described in which MTX produces calcium influx via the sodium-hydrogen exchanger (NHX). For the first time, we found that VGSC blockers partially blocked the MTX-induced calcium influx, intracellular acidification, and protected against the short-term MTX-induced cytotoxicity. The results presented here provide the first report that shows the comparative effects of two prototypical ciguatera toxins, CTX 3C

Polyploidization of liver cells.

Science.gov (United States)

Celton-Morizur, Séverine; Desdouets, Chantal

2010-01-01

Eukaryotic organisms usually contain a diploid complement of chromosomes. However, there are a number of exceptions. Organisms containing an increase in DNA content by whole number multiples of the entire set of chromosomes are defined as polyploid. Cells that contain more than two sets of chromosomes were first observed in plants about a century ago and it is now recognized that polyploidy cells form in many eukaryotes under a wide variety of circumstance. Although it is less common in mammals, some tissues, including the liver, show a high percentage of polyploid cells. Thus, during postnatal growth, the liver parenchyma undergoes dramatic changes characterized by gradual polyploidization during which hepatocytes of several ploidy classes emerge as a result of modified cell-division cycles. This process generates the successive appearance of tetraploid and octoploid cell classes with one or two nuclei (mononucleated or binucleated). Liver cells polyploidy is generally considered to indicate terminal differentiation and senescence and to lead both to the progressive loss of cell pluripotency and a markedly decreased replication capacity. In adults, liver polyploidization is differentially regulated upon loss of liver mass and liver damage. Interestingly, partial hepatectomy induces marked cell proliferation followed by an increase in liver ploidy. In contrast, during hepatocarcinoma (HCC), growth shifts to a nonpolyploidizing pattern and expansion of the diploid hepatocytes population is observed in neoplastic nodules. Here we review the current state of understanding about how polyploidization is regulated during normal and pathological liver growth and detail by which mechanisms hepatocytes become polyploid.

Chemoprotective effect of insulin-like growth factor I against acetaminophen-induced cell death in Chang liver cells via ERK1/2 activation

International Nuclear Information System (INIS)

Hwang, Hye-Jung; Kwon, Mi-Jin; Nam, Taek-Jeong

2007-01-01

The insulin-like growth factor (IGF) system and type-I IGF receptor (IGF-IR) signaling are involved in protecting against chemotherapeutic drug-induced cell death in human hepatoma cells. Acetaminophen (AAP) hepatotoxicity is the leading cause of liver failure, and the prevention of AAP-induced cell death has been the focus of many studies. We determined whether IGF-I could protect against AAP-induced cell death in Chang liver cells and investigated the protective mechanism. Based on the results of MTS assays, LDH release assays, Hoechst 33342 cell staining, and DNA fragmentation experiments, AAP induced cell death in a dose-dependent manner. According to Western blot analysis, treatment with AAP increased the level of poly(ADP-ribose) polymerase (PARP) fragments in cells compared with that in control cells; however, caspase-3, a critical signaling molecule in apoptosis, was not activated after AAP overdose. Moreover, combined treatment with AAP and IGF-I inhibited PARP cleavage, which was consistent with the ability of IGF-I to restore the level of glutathione (GSH) and cell viability in GSH and MTS assays, respectively. We investigated whether the protective effect of IGF-I against AAP cytotoxicity is related to the extracellular signal-related kinase ERK1/2, which is generally activated by mitogenic and proliferative stimuli such as growth factors. Compared with AAP treatment alone, IGF-I and AAP co-treatment increased ERK1/2 phosphorylation but inhibited PARP cleavage. Thus ERK1/2 activation is instrumental in the protective effect of IGF-I against AAP-induced cell death in Chang liver cells

Salecan protected against concanavalin A-induced acute liver injury by modulating T cell immune responses and NMR-based metabolic profiles

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Sun, Qi; Xu, Xi, E-mail: xuxi@njust.edu.cn; Yang, Xiao; Weng, Dan; Wang, Junsong; Zhang, Jianfa

2017-02-15

Salecan, a water-soluble extracellular β-glucan produced by Agrobacterium sp. ZX09, has been reported to exhibit a wide range of biological effects. The aims of the present study were to investigate the protective effect of salecan against Concanavalin A (ConA)-induced hepatitis, a well-established animal model of immune-mediated liver injury, and to search for possible mechanisms. C57BL/6 mice were pretreated with salecan followed by ConA injection. Salecan treatment significantly reduced ConA-induced acute liver injury, and suppressed the expression and secretion of inflammatory cytokines including interferon (IFN)-γ, interleukin (IL)-6 and IL-1β in ConA-induced liver injury model. The high expression levels of chemokines and adhesion molecules such as MIP-1α, MIP-1β, ICAM-1, MCP-1 and RANTES in the liver induced by ConA were also down-regulated after salecan treatment. Salecan inhibited the infiltration and activation of inflammatory cells, especially T cells, in the liver induced by ConA. Moreover, salecan reversed the metabolic profiles of ConA-treated mice towards the control group by partly recovering the metabolic perturbations induced by ConA. Our results suggest the preventive and therapeutic potential of salecan in immune-mediated hepatitis. - Highlights: • Salecan treatment significantly reduced ConA-induced liver injury. • Salecan suppressed the expression and secretion of inflammatory cytokines. • Salecan decreased the expression of chemokines and adhesion molecules in liver. • Salecan inhibited the infiltration and activation of T cells induced by ConA. • Salecan partly recovered the metabolic perturbations induced by ConA.

Thinking outside the liver: induced pluripotent stem cells for hepatic applications.

Science.gov (United States)

Subba Rao, Mekala; Sasikala, Mitnala; Nageshwar Reddy, D

2013-06-14

The discovery of induced pluripotent stem cells (iPSCs) unraveled a mystery in stem cell research, after identification of four re-programming factors for generating pluripotent stem cells without the need of embryos. This breakthrough in generating iPSCs from somatic cells has overcome the ethical issues and immune rejection involved in the use of human embryonic stem cells. Hence, iPSCs form a great potential source for developing disease models, drug toxicity screening and cell-based therapies. These cells have the potential to differentiate into desired cell types, including hepatocytes, under in vitro as well as under in vivo conditions given the proper microenvironment. iPSC-derived hepatocytes could be useful as an unlimited source, which can be utilized in disease modeling, drug toxicity testing and producing autologous cell therapies that would avoid immune rejection and enable correction of gene defects prior to cell transplantation. In this review, we discuss the induction methods, role of reprogramming factors, and characterization of iPSCs, along with hepatocyte differentiation from iPSCs and potential applications. Further, we discuss the location and detection of liver stem cells and their role in liver regeneration. Although tumor formation and genetic mutations are a cause of concern, iPSCs still form a promising source for clinical applications.

Genomic instability induced by 60Co γ ray radiation in normal human liver cells

International Nuclear Information System (INIS)

Gen Xiaohua; Guo Xianhua; Zuo Yahui; Wang Xiaoli; Wang Zhongwen

2007-01-01

Objective: To explore the genomic instability induced by 60 Co γ rays. Methods: The cloning efficiency and micronucleus efficiency of normal human liver cell irradiated by 60 Co γ rays were detected, and the method of single cell gel electrophoresis (SCGE) was carried out to measure DNA chains damage. The fast-growing cells were divided into different dose-groups and then irradiated by 60 Co γ rays. After 40 populations doubling, the progenies were secondly irradiated with 2 Gy 60 Co γ rays. Results: The cloning efficiency decreased with the increase of doses after the initial irradiation. After the survival cells were given second irradiation, both results of SCGE and micronucleus frequency showed that the second damage was correlated with the original irradiation doses. Conclusions: 60 Co γ rays can not only induce the immediate biological effects in liver cells, but also lead to the genomic instability in the descendants that leads to an enhanced frequency of genetic changes occurring among the progeny of the original irradiated cell. The expanding effect of second event helps to study the genomic instability. (authors)

The Use of Induced Pluripotent Stem Cells for the Study and Treatment of Liver Diseases.

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Hansel, Marc C; Davila, Julio C; Vosough, Massoud; Gramignoli, Roberto; Skvorak, Kristen J; Dorko, Kenneth; Marongiu, Fabio; Blake, William; Strom, Stephen C

2016-02-01

Liver disease is a major global health concern. Liver cirrhosis is one of the leading causes of death in the world and currently the only therapeutic option for end-stage liver disease (e.g., acute liver failure, cirrhosis, chronic hepatitis, cholestatic diseases, metabolic diseases, and malignant neoplasms) is orthotropic liver transplantation. Transplantation of hepatocytes has been proposed and used as an alternative to whole organ transplant to stabilize and prolong the lives of patients in some clinical cases. Although these experimental therapies have demonstrated promising and beneficial results, their routine use remains a challenge due to the shortage of donor livers available for cell isolation, variable quality of those tissues, the potential need for lifelong immunosuppression in the transplant recipient, and high costs. Therefore, new therapeutic strategies and more reliable clinical treatments are urgently needed. Recent and continuous technological advances in the development of stem cells suggest they may be beneficial in this respect. In this review, we summarize the history of stem cell and induced pluripotent stem cell (iPSC) technology in the context of hepatic differentiation and discuss the potential applications the technology may offer for human liver disease modeling and treatment. This includes developing safer drugs and cell-based therapies to improve the outcomes of patients with currently incurable health illnesses. We also review promising advances in other disease areas to highlight how the stem cell technology could be applied to liver diseases in the future. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

Intra-Hepatic Depletion of Mucosal-Associated Invariant T Cells in Hepatitis C Virus-Induced Liver Inflammation.

Science.gov (United States)

Bolte, Fabian J; O'Keefe, Ashley C; Webb, Lauren M; Serti, Elisavet; Rivera, Elenita; Liang, T Jake; Ghany, Marc; Rehermann, Barbara

2017-11-01

antiviral therapy. In analyses of paired blood and liver samples from patients with chronic HCV infection before, during, and after antiviral therapy with sofosbuvir and velpatasvir, we found that intrahepatic MAIT cells are activated by monocyte-derived cytokines and depleted in HCV-induced liver inflammation. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Differentiation of human-induced pluripotent stem cell under flow conditions to mature hepatocytes for liver tissue engineering

DEFF Research Database (Denmark)

Starokozhko, Viktoriia; Hemmingsen, Mette; Larsen, Layla

2018-01-01

Hepatic differentiation of human-induced pluripotent stem cells (hiPSCs) under flow conditions in a 3D scaffold is expected to be a major step forward for construction of bioartificial livers. The aims of this study were to induce hepatic differentiation of hiPSCs under perfusion conditions...... and to perform functional comparisons with fresh human precision-cut liver slices (hPCLS), an excellent benchmark for the human liver in vivo. The majority of the mRNA expression of CYP isoenzymes and transporters and the tested CYP activities, Phase II metabolism, and albumin, urea, and bile acid synthesis...... in the hiPSC-derived cells reached values that overlap those of hPCLS, which indicates a higher degree of hepatic differentiation than observed until now. Differentiation under flow compared with static conditions had a strong inducing effect on Phase II metabolism and suppressed AFP expression but resulted...

Role of IRAK-M in alcohol induced liver injury.

Directory of Open Access Journals (Sweden)

Yipeng Wang

Full Text Available Increasing evidence suggests that innate immunity plays an important role in alcohol-induced liver injury and most studies have focused on positive regulation of innate immunity. The main objective of this study was to investigate the negative regulator of innate immunity, IL-1/Toll-like receptor (TLR signaling pathways and interleukin receptor-associated kinase-M (IRAK-M in alcoholic liver injury. We established an alcohol-induced liver injury model using wild type and IRAK-M deficient B6 mice and investigated the possible mechanisms. We found that in the absence of IRAK-M, liver damage by alcohol was worse with higher alanine transaminase (ALT, more immune cell infiltration and increased numbers of IFNγ producing cells. We also found enhanced phagocytic activity in CD68(+ cells. Moreover, our results revealed altered gut bacteria after alcohol consumption and this was more striking in the absence of IRAK-M. Our study provides evidence that IRAK-M plays an important role in alcohol-induced liver injury and IRAK-M negatively regulates the innate and possibly the adaptive immune response in the liver reacting to acute insult by alcohol. In the absence of IRAK-M, the hosts developed worse liver injury, enhanced gut permeability and altered gut microbiota.

H2S-induced S-sulfhydration of pyruvate carboxylase contributes to gluconeogenesis in liver cells.

Science.gov (United States)

Ju, YoungJun; Untereiner, Ashley; Wu, Lingyun; Yang, Guangdong

2015-11-01

Cystathionine gamma-lyase (CSE)-derived hydrogen sulfide (H(2)S) possesses diverse roles in the liver, affecting lipoprotein synthesis, insulin sensitivity, and mitochondrial biogenesis. H(2)S S-sulfhydration is now proposed as a major mechanism for H(2)S-mediated signaling. Pyruvate carboxylase (PC) is an important enzyme for gluconeogenesis. S-sulfhydration regulation of PC by H(2)S and its implication in gluconeogenesis in the liver have been unknown. Gene expressions were analyzed by real-time PCR and western blotting, and protein S-sulfhydration was assessed by both modified biotin switch assay and tag switch assay. Glucose production and PC activity was measured with coupled enzyme assays, respectively. Exogenously applied H(2)S stimulates PC activity and gluconeogenesis in both HepG2 cells and mouse primary liver cells. CSE overexpression enhanced but CSE knockout reduced PC activity and gluconeogenesis in liver cells, and blockage of PC activity abolished H(2)S-induced gluconeogenesis. H(2)S had no effect on the expressions of PC mRNA and protein, while H(2)S S-sulfhydrated PC in a dithiothreitol-sensitive way. PC S-sulfhydration was significantly strengthened by CSE overexpression but attenuated by CSE knockout, suggesting that H(2)S enhances glucose production through S-sulfhydrating PC. Mutation of cysteine 265 in human PC diminished H(2)S-induced PC S-sulfhydration and activity. In addition, high-fat diet feeding of mice decreased both CSE expression and PC S-sulfhydration in the liver, while glucose deprivation of HepG2 cells stimulated CSE expression. CSE/H(2)S pathway plays an important role in the regulation of glucose production through S-sulfhydrating PC in the liver. Tissue-specific regulation of CSE/H(2)S pathway might be a promising therapeutic target of diabetes and other metabolic syndromes. Copyright © 2015 Elsevier B.V. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

Soeda, Junpei; Morgan, Maelle; McKee, Chad; Mouralidarane, Angelina; Lin, ChingI [University College London, Centre for Hepatology, Royal Free Hospital, London NW3 2PF (United Kingdom); Roskams, Tania [Department of Morphology and Molecular Pathology, University of Leuven (Belgium); Oben, Jude A., E-mail: j.oben@ucl.ac.uk [University College London, Centre for Hepatology, Royal Free Hospital, London NW3 2PF (United Kingdom); Department of Gastroenterology and Hepatology, Guy' s and St Thomas' Hospital, London SE1 7EH (United Kingdom)

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

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

International Nuclear Information System (INIS)

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

2012-01-01

Highlights: ► Cigarette smoke may induce liver fibrosis via nicotine receptors. ► Nicotine induces proliferation of hepatic stellate cells (HSCs). ► Nicotine activates hepatic fibrogenic pathways. ► Nicotine receptor antagonists attenuate HSC proliferation. ► 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-α2 and the pro-fibrogenic cytokine transforming growth factor beta 1 (TGF-β1) 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 (α1, β1, delta and epsilon) and neuronal type (α3, α6, α7, β2 and β4) nAChR subunits at the mRNA level. Among these subunits, α3, α7, β1 and ε were predominantly expressed as confirmed by Western blotting. Nicotine induced hHSC proliferation was attenuated by mecamylamine (p < 0.05). Additionally, collagen1-α2 and TGF-β1 mRNA expression were significantly upregulated by nicotine and inhibited by mecamylamine. α1 and α3-nAChR mRNA expression was significantly upregulated in NASH fibrosis compared to normal livers. Conclusion: Nicotine at levels in smokers’ blood is pro-fibrogenic, through

Kupffer cells activation promoted binge drinking-induced fatty liver by activating lipolysis in white adipose tissues.

Science.gov (United States)

Zhao, Yu-Ying; Yang, Rui; Xiao, Mo; Guan, Min-Jie; Zhao, Ning; Zeng, Tao

2017-09-01

Kupffer cells (KCs) have been suggested to play critical roles in chronic ethanol induced early liver injury, but the role of KCs in binge drinking-induced hepatic steatosis remains unclear. This study was designed to investigate the roles of KCs inhibitor (GdCl 3 ) and TNF-α antagonist (etanercept) on binge drinking-induced liver steatosis and to explore the underlying mechanisms. C57BL/6 mice were exposed to three doses of ethanol (6g/kg body weight) to mimic binge drinking-induced fatty liver. The results showed that both GdCl 3 and etanercept partially but significantly alleviated binge drinking-induced increase of hepatic triglyceride (TG) level, and reduced fat droplets accumulation in mice liver. GdCl 3 but not etanercept significantly blocked binge drinking-induced activation of KCs. However, neither GdCl 3 nor etanercept could affect binge drinking-induced decrease of PPAR-α, ACOX, FAS, ACC and SCD protein levels, or increase of the LC3 II/LC3 I ratio and p62 protein level. Interestingly, both GdCl 3 and etanercept significantly suppressed binge drinking-induced phosphorylation of HSL in epididymal adipose tissues. Results of in vitro studies with cultured epididymal adipose tissues showed that TNF-α could increase the phosphorylation of HSL in adipose tissues and upgrade the secretion of free fatty acid (FFA) in the culture medium. Taken together, KCs inhibitor and TNF-α antagonist could partially attenuate binge drinking-induced liver steatosis, which might be attributed to the suppression of mobilization of white adipose tissues. These results suggest that KCs activation may promote binge drinking-induced fatty liver by TNF-α mediated activation of lipolysis in white adipose tissues. Copyright © 2017 Elsevier B.V. All rights reserved.

Pomegranate protects against arsenic-induced p53-dependent ROS-mediated inflammation and apoptosis in liver cells.

Science.gov (United States)

Choudhury, Sreetama; Ghosh, Sayan; Mukherjee, Sudeshna; Gupta, Payal; Bhattacharya, Saurav; Adhikary, Arghya; Chattopadhyay, Sreya

2016-12-01

Molecular mechanisms involved in arsenic-induced toxicity are complex and elusive. Liver is one of the most favored organs for arsenic toxicity as methylation of arsenic occurs mostly in the liver. In this study, we have selected a range of environmentally relevant doses of arsenic to examine the basis of arsenic toxicity and the role of pomegranate fruit extract (PFE) in combating it. Male Swiss albino mice exposed to different doses of arsenic presented marked hepatic injury as evident from histological and electron microscopic studies. Increased activities of enzymes alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and alkaline phosphatase corroborated extensive liver damage. It was further noted that arsenic exposure initiated reactive oxygen species (ROS)-dependent apoptosis in the hepatocytes involving loss of mitochondrial membrane potential. Arsenic significantly increased nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor-κB (NF-κB), coupled with increase in phosphorylated Iκ-B, possibly as adaptive cellular survival strategies. Arsenic-induced oxidative DNA damage to liver cells culminated in p53 activation and increased expression of p53 targets like miR-34a and Bax. Pomegranate polyphenols are known to possess remarkable antioxidant properties and are capable of protecting normal cells from various stimuli-induced oxidative stress and toxicities. We explored the protective role of PFE in ameliorating arsenic-induced hepatic damage. PFE was shown to reduce ROS generation in hepatocytes, thereby reducing arsenic-induced Nrf2 activation. PFE also inhibited arsenic-induced NF-κB-inflammatory pathway. Data revealed that PFE reversed arsenic-induced hepatotoxicity and apoptosis by modulating the ROS/Nrf2/p53-miR-34a axis. For the first time, we have mapped the possible signaling pathways associated with arsenic-induced hepatotoxicity and its rescue by pomegranate polyphenols. Copyright

Protective effects of C-phycocyanin on alcohol-induced acute liver injury in mice

Science.gov (United States)

Xia, Dong; Liu, Bing; Luan, Xiying; Sun, Junyan; Liu, Nana; Qin, Song; Du, Zhenning

2016-03-01

Excessive alcohol consumption leads to liver disease. Extensive evidence suggests that C-phycocyanin (C-PC), a chromophore phycocyanobilin derived from Spirulina platensis, exerts protective effects against chemical-induced organ damage. In this study, we investigated whether C-PC could protect against ethanol-induced acute liver injury. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (CHOL), low-density lipoprotein (LDL), liver homogenate malondialdehyde (MDA), superoxide dismutase (SOD) content were measured, and pathological examination of liver sections were examined. C-PC showed obvious inhibitory effects on serum ALT, AST, TG, CHOL, LDL and MDA, and SOD content significantly increased in the liver. The structure of hepatic lobules was clear, liver sinus returned to normal, and liver cell cords were arranged in neat rows. Cloudiness, swelling, inflammatory cell infiltration and spotty necrosis of liver cells were significantly reduced. Therefore, C-PC can significantly protect against ethanol-induced acute liver injury.

Phenobarbital Induces Alterations in the Proteome of Hepatocytes and Mesenchymal Cells of Rat Livers

Science.gov (United States)

Klepeisz, Philip; Sagmeister, Sandra; Haudek-Prinz, Verena; Pichlbauer, Melanie; Grasl-Kraupp, Bettina; Gerner, Christopher

2013-01-01

Preceding studies on the mode of action of non-genotoxic hepatocarcinogens (NGCs) have concentrated on alterations induced in hepatocytes (HCs). A potential role of non-parenchymal liver cells (NPCs) in NGC-driven hepatocarcinogenesis has been largely neglected so far. The aim of this study is to characterize NGC-induced alterations in the proteome profiles of HCs as well as NPCs. We chose the prototypic NGC phenobarbital (PB) which was applied to male rats for a period of 14 days. The livers of PB-treated rats were perfused by collagenase and the cell suspensions obtained were subjected to density gradient centrifugation to separate HCs from NPCs. In addition, HCs and NPC isolated from untreated animals were treated with PB in vitro. Proteome profiling was done by CHIP-HPLC and ion trap mass spectrometry. Proteome analyses of the in vivo experiments showed many of the PB effects previously described in HCs by other methods, e.g. induction of phase I and phase II drug metabolising enzymes. In NPCs proteins related to inflammation and immune regulation such as PAI-1 and S100-A10, ADP-ribosyl cyclase 1 and to cell migration such as kinesin-1 heavy chain, myosin regulatory light chain RLC-A and dihydropyrimidinase-related protein 1 were found to be induced, indicating major PB effects on these cells. Remarkably, in vitro treatment of HCs and NPCs with PB hardly reproduced the proteome alterations observed in vivo, indicating differences of NGC induced responses of cells at culture conditions compared to the intact organism. To conclude, the present study clearly demonstrated that PB induces proteome alterations not only in HCs but also in NPCs. Thus, any profound molecular understanding on the mode of action of NGCs has to consider effects on cells of the hepatic mesenchyme. PMID:24204595

Phenobarbital induces alterations in the proteome of hepatocytes and mesenchymal cells of rat livers.

Directory of Open Access Journals (Sweden)

Philip Klepeisz

Full Text Available Preceding studies on the mode of action of non-genotoxic hepatocarcinogens (NGCs have concentrated on alterations induced in hepatocytes (HCs. A potential role of non-parenchymal liver cells (NPCs in NGC-driven hepatocarcinogenesis has been largely neglected so far. The aim of this study is to characterize NGC-induced alterations in the proteome profiles of HCs as well as NPCs. We chose the prototypic NGC phenobarbital (PB which was applied to male rats for a period of 14 days. The livers of PB-treated rats were perfused by collagenase and the cell suspensions obtained were subjected to density gradient centrifugation to separate HCs from NPCs. In addition, HCs and NPC isolated from untreated animals were treated with PB in vitro. Proteome profiling was done by CHIP-HPLC and ion trap mass spectrometry. Proteome analyses of the in vivo experiments showed many of the PB effects previously described in HCs by other methods, e.g. induction of phase I and phase II drug metabolising enzymes. In NPCs proteins related to inflammation and immune regulation such as PAI-1 and S100-A10, ADP-ribosyl cyclase 1 and to cell migration such as kinesin-1 heavy chain, myosin regulatory light chain RLC-A and dihydropyrimidinase-related protein 1 were found to be induced, indicating major PB effects on these cells. Remarkably, in vitro treatment of HCs and NPCs with PB hardly reproduced the proteome alterations observed in vivo, indicating differences of NGC induced responses of cells at culture conditions compared to the intact organism. To conclude, the present study clearly demonstrated that PB induces proteome alterations not only in HCs but also in NPCs. Thus, any profound molecular understanding on the mode of action of NGCs has to consider effects on cells of the hepatic mesenchyme.

Xenotransplantation of neonatal porcine liver cells.

Science.gov (United States)

Garkavenko, O; Emerich, D F; Muzina, M; Muzina, Z; Vasconcellos, A V; Ferguson, A B; Cooper, I J; Elliott, R B

2005-01-01

Xenotransplantation of porcine liver cell types may provide a means of overcoming the shortage of suitable donor tissues to treat hepatic diseases characterized by inherited inborn errors of metabolism or protein production. Here we report the successful isolation, culture, and xenotransplantation of liver cells harvested from 7- to 10-day-old piglets. Liver cells were isolated and cultured immediately after harvesting. Cell viability was excellent (>90%) over the duration of the in vitro studies (3 weeks) and the cultured cells continued to significantly proliferate. These cells also retained their normal secretory and metabolic capabilities as determined by continued release of albumin, factor 8, and indocyanin green (ICG) uptake. After 3 weeks in culture, porcine liver cells were loaded into immunoisolatory macro devices (Theracyte devices) and placed into the intraperitoneal cavity of immunocompetant CD1 mice. Eight weeks later, the devices were retrieved and the cells analyzed for posttransplant determinations of survival and function. Post mortem analysis confirmed that the cell-loaded devices were biocompatible, and were well-tolerated without inducing any notable inflammatory reaction in the tissues immediately surrounding the encapsulated cells. Finally, the encapsulated liver cells remained viable and functional as determined by histologic analyses and ICG uptake/release. The successful harvesting, culturing, and xenotransplantation of functional neonatal pig liver cells support the continued development of this approach for treating a range of currently undertreated or intractable hepatic diseases.

Hepatic Differentiation of Human Induced Pluripotent Stem Cells in a Perfused 3D Porous Polymer Scaffold for Liver Tissue Engineering

DEFF Research Database (Denmark)

Hemmingsen, Mette; Muhammad, Haseena Bashir; Mohanty, Soumyaranjan

A huge shortage of liver organs for transplantation has motivated the research field of tissue engineering to develop bioartificial liver tissue and even a whole liver. The goal of NanoBio4Trans is to create a vascularized bioartificial liver tissue, initially as a liver-support system. Due...... to limitations of primary hepatocytes regarding availability and maintenance of functionality, stem cells and especially human induced pluripotent stem cells (hIPS cells) are an attractive cell source for liver tissue engineering. The aim of this part of NanoBio4Trans is to optimize culture and hepatic...... differentiation of hIPS-derived definitive endoderm (DE) cells in a 3D porous polymer scaffold built-in a perfusable bioreactor. The use of a microfluidic bioreactor array enables the culture of 16 independent tissues in one experimental run and thereby an optimization study to be performed....

Ectopic Liver Tissue Formation in Rats with Induced Liver Fibrosis

Directory of Open Access Journals (Sweden)

Bauyrzhan Umbayev

2014-12-01

Full Text Available Introduction: The possible alternative approach to whole-organ transplantation is a cell-based therapy, which can also be used as a "bridge" to liver transplantation.  However, morphological and functional changes in the liver of patients suffering from chronic liver fibrosis and cirrhosis restrict the effectiveness of direct cell transplantation. Therefore, extra hepatic sites for cell transplantation, including the spleen, pancreas, peritoneal cavity, and subrenal capsule, could be a useful therapeutic approach for compensation of liver functions. However, a method of transplantation of hepatocytes into ectopic sites is needed to improve hepatocyte engraftment. Previously published data has demonstrated that mouse lymph nodes can support the engraftment and proliferation of hepatocytes as ES and rescue Fah mice from lethal liver failure. Thus, the aim of the study was to evaluate the engraftment of i.p. injected allogeneic hepatocytes into extra hepatic sites in albino rats with chemically induced liver fibrosis (LF. Materials and methods: Albino rats were randomly divided into 4 groups: (1 intact group (n = 18; (2 rats with induced LF (n = 18; (3 rats with induced LF and transplanted with hepatocytes (n = 18; (4 as a control, rats were treated with cyclosporine A only (n = 18. In order to prevent an immune response, groups 2 and 3 were subjected to immunosuppression by cyclosporine A (25 mg/kg per day. LF was induced using N-nitrosodimethylamine (NDMA, i.p., 10 mg/kg, three times a week for 4 weeks and confirmed by histological analysis of the liver samples. Hepatocytes transplantation (HT was performed two days after NDMA exposure cessation by i.p. injection of 5×106 freshly isolated allogeneic hepatocytes. Liver function was assessed by quantifying blood biochemical parameters (ALT, AST, GGT, total protein, bilirubin, and albumin at 1 week, 1 month, and 2 months after hepatocytes transplantation (HT. To confirm a hepatocytes�

Stem Cells Transplantation in the Treatment of Patients with Liver Failure.

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Tao, Ya-Chao; Wang, Meng-Lan; Chen, En-Qiang; Tang, Hong

2018-02-23

Liver failure is a life-threatening liver disease encompassing severe acute deterioration of liver function. Emergency liver transplantation is the only curative treatment for liver failure, but is restricted by the severe shortage of organ donors. Stem cell, including embroyonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, hematopoietic stem cells and hepatic progenitor cells, have capacity to proliferate and differentiate and could be used in a variety of liver diseases including hereditary liver diseases, cirrhosis and liver failure. We summarized the basic experimental and clinical advances of stem cell transplantation in liver failure treatment, and also discussed the advantages and disadvantage of different stem cells subtype in this field, aiming to provide a perspective on the stem cell-based therapy for liver failure. Stem cells, especially mesenchymal stem cells (mainly low immunogenicity and paracrine characteristics) and induced pluripotent stem cells (generation of desired cell type from somatic cell), are feasible candidates for cell therapy in the treatment of liver failure, but there are some drawbacks remaining to be resolved, such as low engraftment, cryotpreservation methods and tumorigenesis. Stem cell transplantation is a promising but challenging strategy and paves a new way for curing liver failure. But more efforts need to be made to overcome problems before this new strategy could be safely and effectively applied to humans. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Amarogentin Induces Apoptosis of Liver Cancer Cells via Upregulation of p53 and Downregulation of Human Telomerase Reverse Transcriptase in Mice

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Li, Runqin; Zhang, Yinglin

2016-01-01

Background and Objective: Amarogentin has been reported to have a preventive effect on liver cancer via inducing cancer cell apoptosis. We attempted to elucidate the roles of p53-associated apoptosis pathways in the chemopreventive mechanism of amarogentin. The findings of this study will facilitate the development of a novel supplementary strategy for the treatment of liver cancer. Materials and Methods: The purity of amarogentin was assessed by high-performance liquid chromatography. The inhibitory ratios of the liver cell lines were determined using a Cell Counting Kit-8 following treatment with a gradient concentration of amarogentin. Cell apoptosis was detected by flow cytometry using annexin V-fluorescein isothiocyanate/propidium iodide kits. The gene and protein expression of p53-associated molecules, such as Akt, human telomerase reverse transcriptase, RelA, and p38, was detected by real-time quantitative polymerase chain reaction, Western blotting, and immunohistochemical staining in liver cancer cells and mouse tumor tissues after treatment with amarogentin. Results: The inhibitory effect of amarogentin on cell proliferation was more obvious in liver cancer cells, and amarogentin was more likely to induce the apoptosis of liver cancer cells than that of normal liver cells. The gene and protein expression levels of Akt, RelA, and human telomerase reverse transcriptase were markedly higher in the control group than in the preventive group and treatment groups. Only the expression of human telomerase reverse transcriptase was downregulated, accompanied by the upregulation of p53. Conclusion: The results of our study suggest that amarogentin promotes apoptosis of liver cancer cells by the upregulation of p53 and downregulation of human telomerase reverse transcriptase and prevents the malignant transformation of these cells. PMID:27402632

JNK1 induces hedgehog signaling from stellate cells to accelerate liver regeneration in mice.

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Langiewicz, Magda; Graf, Rolf; Humar, Bostjan; Clavien, Pierre A

2018-04-27

To improve outcomes of two-staged hepatectomies for large/multiple liver tumors, portal vein ligation (PVL) has been combined with parenchymal transection (coined ALPPS; Associated Liver Partition and Portal vein ligation for Staged hepatectomy) to greatly accelerate liver regeneration. In a novel ALPPS mouse model, we have reported paracrine Indian hedgehog (IHH) signaling from stellate cells as an early contributor to augmented regeneration. Here, we sought to identify upstream regulators of IHH. ALPPS in mice was compared against PVL and additional control surgeries. Potential IHH regulators were identified through in silico mining of transcriptomic data. JNK1 activity was reduced through SP600125 to evaluate its effects on IHH signaling. Recombinant IHH was injected after JNK diminution to substantiate their relationship during accelerated liver regeneration. Mining linked Ihh to Mapk8. JNK1 upregulation after ALPPS was validated and preceded the IHH peak. On immunofluorescence, JNK1 and IHH co-localized in ASMA-positive non-parenchymal cells. Inhibition of JNK1 prior to ALPPS surgery reduced liver weight gain to PVL levels and was accompanied by downregulation of hepatocellular proliferation and the IHH-GLI1-CCND1 axis. In JNK1-inhibited mice, recombinant IHH restored ALPPS-like acceleration of regeneration and re-elevated JNK1 activity, suggesting the presence of a positive IHH-JNK1 feedback loop. JNK1-mediated induction of IHH paracrine signaling from HSCs is essential for accelerated regeneration of parenchymal mass. The JNK1-IHH axis is a mechanism unique to ALPPS surgery and may point to therapeutic alternatives for patients with insufficient regenerative capacity. ALPPS, a novel two-staged hepatectomy, induces an unprecedented acceleration of liver regeneration to enable treatment of unresectable liver tumors. Here, we demonstrate JNK1-IHH signaling as a mechanism underlying the regenerative acceleration induced by ALPPS. Copyright © 2018 European

Chitosan nanoparticles from marine squid protect liver cells against N-diethylnitrosoamine-induced hepatocellular carcinoma.

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Subhapradha, Namasivayam; Shanmugam, Vairamani; Shanmugam, Annaian

2017-09-01

Rationale of this study was framed to investigate the protective effect and anti-cancer property of nanoparticles based on chitosan isolated from squid, Sepioteuthis lessoniana, on hepatic cells in N-Nitrosodiethylamine-induced hepatocellular carcinoma in rats. The results conferred that the chitosan nanoparticle supplementation had a protective effect on liver cells by reducing the levels of marker enzymes and bilirubin and thus increasing the albumin levels. The level of reduced glutathione, ascorbic acid and α-tocopherol significantly increased in both post- and pre-treatment with chitosan nanoparticles. The levels of antioxidant enzymes were enhanced and lipid peroxidation products were diminished while treating nitrosodiethylamine-induced hepatocellular carcinoma with chitosan nanoparticles. Supplementation of chitosan nanoparticles had potent anti-hyperlipidemic property that was evidenced by monitoring the serum lipid levels and its components. Animals pre-treated with chitosan nanoparticles along with nitrosodiethylamine showed a significant reduction in the total cholesterol and triglycerides levels with increase in the levels of phospholipids and free fatty acids. Chitosan nanoparticles treated rats showed significant increment in high-density lipoprotein cholesterol and reduction in low-density lipoprotein and very low-density lipoprotein cholesterol when compared with levels in nitrosodiethylamine-induced hepatocellular carcinoma. Nitrosodiethylamine-induced carcinoma changes on circulation and hepatic antioxidant defense mechanism were regulated by chitosan nanoparticles, concluding that the chitosan nanoparticles have a potent protective effect on liver cells which might be due to its robust antioxidant and anti-lipidemic property. Copyright © 2017 Elsevier Ltd. All rights reserved.

Role of Kupffer Cells in Thioacetamide-Induced Cell Cycle Dysfunction

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Mirandeli Bautista

2011-09-01

Full Text Available It is well known that gadolinium chloride (GD attenuates drug-induced hepatotoxicity by selectively inactivating Kupffer cells. In the present study the effect of GD in reference to cell cycle and postnecrotic liver regeneration induced by thioacetamide (TA in rats was studied. Two months male rats, intraveously pretreated with a single dose of GD (0.1 mmol/Kg, were intraperitoneally injected with TA (6.6 mmol/Kg. Samples of blood and liver were obtained from rats at 0, 12, 24, 48, 72 and 96 h following TA intoxication. Parameters related to liver damage were determined in blood. In order to evaluate the mechanisms involved in the post-necrotic regenerative state, the levels of cyclin D and cyclin E as well as protein p27 and Proliferating Cell Nuclear Antigen (PCNA were determined in liver extracts because of their roles in the control of cell cycle check-points. The results showed that GD significantly reduced the extent of necrosis. Noticeable changes were detected in the levels of cyclin D1, cyclin E, p27 and PCNA when compared to those induced by thioacetamide. Thus GD pre-treatment reduced TA-induced liver injury and accelerated the postnecrotic liver regeneration. These results demonstrate that Kupffer cells are involved in TA-induced liver and also in the postnecrotic proliferative liver states.

Fucoidan from Fucus vesiculosus Protects against Alcohol-Induced Liver Damage by Modulating Inflammatory Mediators in Mice and HepG2 Cells

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Jung Dae Lim

2015-02-01

Full Text Available Fucoidan is an l-fucose-enriched sulfated polysaccharide isolated from brown algae and marine invertebrates. In this study, we investigated the protective effect of fucoidan from Fucus vesiculosus on alcohol-induced murine liver damage. Liver injury was induced by oral administration of 25% alcohol with or without fucoidan (30 mg/kg or 60 mg/kg for seven days. Alcohol administration increased serum aspartate aminotransferase and alanine aminotransferase levels, but these increases were suppressed by the treatment of fucoidan. Transforming growth factor beta 1 (TGF-β1, a liver fibrosis-inducing factor, was highly expressed in the alcohol-fed group and human hepatoma HepG2 cell; however, the increase in TGF-β1 expression was reduced following fucoidan administration. Treatment with fucoidan was also found to significantly reduce the production of inflammation-promoting cyclooygenase-2 and nitric oxide, while markedly increasing the expression of the hepatoprotective enzyme, hemeoxygenase-1, on murine liver and HepG2 cells. Taken together, the antifibrotic and anti-inflammatory effects of fucoidan on alcohol-induced liver damage may provide valuable insights into developing new therapeutics or interventions.

Macrophages and dendritic cells emerge in the liver during intestinal inflammation and predispose the liver to inflammation.

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Yohei Mikami

Full Text Available The liver is a physiological site of immune tolerance, the breakdown of which induces immunity. Liver antigen-presenting cells may be involved in both immune tolerance and activation. Although inflammatory diseases of the liver are frequently associated with inflammatory bowel diseases, the underlying immunological mechanisms remain to be elucidated. Here we report two murine models of inflammatory bowel disease: RAG-2(-/- mice adoptively transferred with CD4(+CD45RB(high T cells; and IL-10(-/- mice, accompanied by the infiltration of mononuclear cells in the liver. Notably, CD11b(-CD11c(lowPDCA-1(+ plasmacytoid dendritic cells (DCs abundantly residing in the liver of normal wild-type mice disappeared in colitic CD4(+CD45RB(high T cell-transferred RAG-2(-/- mice and IL-10(-/- mice in parallel with the emergence of macrophages (Mφs and conventional DCs (cDCs. Furthermore, liver Mφ/cDCs emerging during intestinal inflammation not only promote the proliferation of naïve CD4(+ T cells, but also instruct them to differentiate into IFN-γ-producing Th1 cells in vitro. The emergence of pathological Mφ/cDCs in the liver also occurred in a model of acute dextran sulfate sodium (DSS-induced colitis under specific pathogen-free conditions, but was canceled in germ-free conditions. Last, the Mφ/cDCs that emerged in acute DSS colitis significantly exacerbated Fas-mediated hepatitis. Collectively, intestinal inflammation skews the composition of antigen-presenting cells in the liver through signaling from commensal bacteria and predisposes the liver to inflammation.

PROTECTIVE EFFECTS OF HYPOTHALAMIC BETA-ENDORPHIN NEURONS AGAINST ALCOHOL-INDUCED LIVER INJURIES AND LIVER CANCERS IN RAT ANIMAL MODELS

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Murugan, Sengottuvelan; Boyadjieva, Nadka; Sarkar, Dipak K.

2014-01-01

Background Recently, retrograde tracing has provided evidence for an influence of hypothalamic β-endorphin (BEP) neurons on the liver, but functions of these neurons are not known. We evaluated the effect of BEP neuronal activation on alcohol-induced liver injury and hepatocellular cancer. Methods Male rats received either BEP neuron transplants or control transplants in the hypothalamus and randomly assigned to feeding alcohol-containing liquid diet or control liquid diet for 8 weeks or to treatment of a carcinogen diethylnitrosamine (DEN). Liver tissues of these animals were analyzed histochemically and biochemically for tissue injuries or cancer. Results Alcohol-feeding increased liver weight and induced several histopathological changes such as prominent microvesicular steatosis and hepatic fibrosis. Alcohol feeding also increased protein levels of triglyceride, hepatic stellate cell activation factors and catecholamines in the liver and endotoxin levels in the plasma. However, these effects of alcohol on the liver were reduced in animals with BEP neuron transplants. BEP neuron transplants also suppressed carcinogen-induced liver histopathologies such as extensive fibrosis, large focus of inflammatory infiltration, hepatocelluar carcinoma, collagen deposition, numbers of preneoplastic foci, levels of hepatic stellate cell activation factors and catecholamines, as well as inflammatory milieu and the levels of NK cell cytotoxic factors in the liver. Conclusion These findings are the first evidence for a role of hypothalamic BEP neurons in influencing liver functions. Additionally, the data identify that BEP neuron transplantation prevents hepatocellular injury and hepatocellular carcinoma formation possibly via influencing the immune function. PMID:25581653

Exogenous FABP4 induces endoplasmic reticulum stress in HepG2 liver cells.

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Bosquet, Alba; Guaita-Esteruelas, Sandra; Saavedra, Paula; Rodríguez-Calvo, Ricardo; Heras, Mercedes; Girona, Josefa; Masana, Lluís

2016-06-01

Fatty acid binding protein 4 (FABP4) is an intracellular fatty acid (FA) carrier protein that is, in part, secreted into circulation. Circulating FABP4 levels are increased in obesity, diabetes and other insulin resistance (IR) diseases. FAs contribute to IR by promoting endoplasmic reticulum stress (ER stress) and altering the insulin signaling pathway. The effect of FABP4 on ER stress in the liver is not known. The aim of this study was to investigate whether exogenous FABP4 (eFABP4) is involved in the lipid-induced ER stress in the liver. HepG2 cells were cultured with eFABP4 (40 ng/ml) with or without linoleic acid (LA, 200 μM) for 18 h. The expression of ER stress-related markers was determined by Western blotting (ATF6, EIF2α, IRE1 and ubiquitin) and real-time PCR (ATF6, CHOP, EIF2α and IRE1). Apoptosis was studied by flow cytometry using Annexin V-FITC and propidium iodide staining. eFABP4 increased the ER stress markers ATF6 and IRE1 in HepG2 cells. This effect led to insulin resistance mediated by changes in AKT and JNK phosphorylation. Furthermore, eFABP4 significantly induced both apoptosis, as assessed by flow cytometry, and CHOP expression, without affecting necrosis and ubiquitination. The presence of LA increased the ER stress response induced by eFABP4. eFABP4, per se, induces ER stress and potentiates the effect of LA in HepG2 cells, suggesting that FABP4 could be a link between obesity-associated metabolic abnormalities and hepatic IR mechanisms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Ethanol and liver: Recent insights into the mechanisms of ethanol-induced fatty liver

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Liu, Jinyao

2014-01-01

Alcoholic fatty liver disease (AFLD), a potentially pathologic condition, can progress to steatohepatitis, fibrosis, and cirrhosis, leading to an increased probability of hepatic failure and death. Alcohol induces fatty liver by increasing the ratio of reduced form of nicotinamide adenine dinucleotide to oxidized form of nicotinamide adenine dinucleotide in hepatocytes; increasing hepatic sterol regulatory element-binding protein (SREBP)-1, plasminogen activator inhibitor (PAI)-1, and early growth response-1 activity; and decreasing hepatic peroxisome proliferator-activated receptor-α activity. Alcohol activates the innate immune system and induces an imbalance of the immune response, which is followed by activated Kupffer cell-derived tumor necrosis factor (TNF)-α overproduction, which is in turn responsible for the changes in the hepatic SREBP-1 and PAI-1 activity. Alcohol abuse promotes the migration of bone marrow-derived cells (BMDCs) to the liver and then reprograms TNF-α expression from BMDCs. Chronic alcohol intake triggers the sympathetic hyperactivity-activated hepatic stellate cell (HSC) feedback loop that in turn activates the HSCs, resulting in HSC-derived TNF-α overproduction. Carvedilol may block this feedback loop by suppressing sympathetic activity, which attenuates the progression of AFLD. Clinical studies evaluating combination therapy of carvedilol with a TNF-α inhibitor to treat patients with AFLD are warranted to prevent the development of alcoholic liver disease. PMID:25356030

Aqueous extract of Tribulus terrestris Linn induces cell growth arrest and apoptosis by down-regulating NF-κB signaling in liver cancer cells.

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Kim, Hye Jin; Kim, Jin Chul; Min, Jung Sun; Kim, Mi-Jee; Kim, Ji Ae; Kor, Myung Ho; Yoo, Hwa Seung; Ahn, Jeong Keun

2011-06-14

A medicinal herb Tribulus terrestris Linn has been used to treat various diseases including hepatocellular carcinoma. The aim of the present study was to investigate the anticancer activity of Tribulus terrestris Linn (TT) in liver cancer cells. The antitumor activity of aqueous TT extract was analyzed by testing the cytotoxicity and the effect on clonogenecity in HepG2 cells. Apoptosis and cell cycle arrest induced by TT were dissected by flow cytometry and its inhibitory effect on NF-κB activity was determined by analyzing the expression levels of NF-κB/IκB subunit proteins. The suppression of NF-κB-regulated gene expression by TT was assessed by RT-PCR. TT extract repressed clonogenecity and proliferation, induced apoptosis, and enhanced accumulation in the G0/G1 phase of liver cancer cells. It also turned out that TT extract inhibited NF-κB-dependent reporter gene expression and NF-κB subunit p50 expression, while it enhanced the cellular level of IκBα by inhibiting the phosphorylation and degradation of IκBα. In addition, IKK activity was inhibited in a dose-dependent manner. Furthermore, TT extract suppressed the transcription of genes associated with cell cycle regulation, anti-apoptosis, and invasion. These data showed that TT extract blocks proliferation and induces apoptosis in human liver cancer cells through the inhibition of NF-κB signaling. Aqueous TT extract can be used as an anticancer drug for hepatocellular carcinoma patients. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Cadmium Chloride Induces DNA Damage and Apoptosis of Human Liver Carcinoma Cells via Oxidative Stress

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Anthony Skipper

2016-01-01

Full Text Available 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.

[Effects of three Wenyang Jianpi Tang on cell proliferation and apoptosis of nonalcoholic fatty liver cells].

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Yang, Jia-Yao; Tao, Dong-Qing; Liu, Song; Zhang, Shu; Ma, Wei; Shi, Zhao-Hong

2017-04-01

To investigate the effects of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang on the cell proliferation and apoptosis of nonalcoholic fatty liver cells through the nonalcoholic fatty liver cell model established by inducing L02 cells with oleic acid. Different concentrations of oleic acid were added into L02 cells to induce the nonalcoholic fatty liver cell model. Oil red O staining was used to observe fatty droplets of fatty liver cells. Automatic biochemical analyzer was used to detect the levels of aspartic transaminase(AST), alanine aminotransferase(ALT), total cholesterol(TC), and triglyceride(TG) in the cell supernatants. There were five groups, namely normal group, model group, model and Sijunzi Tang group, model and Lizhong Tang group, and model and Fuzi Lizhong Tang group. The cell proliferation and apoptosis of the five groups were detected by MTT colorimetry test and flow cytometer. The expressions of PCNA, cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, Bax and Bcl-2 proteins of the five groups were detected by Western blot. The oil red O staining results showed that the optimum concentration of oleic acid that was used to induce nonalcoholic fatty liver cell models was 80 mg•L-1. The levels of AST, ALT, TC and TG in the nonalcoholic fatty liver cell supernatants were higher than that in normal liver cell supernatants(PTang, Lizhong Tang and Fuzi Lizhong Tang could effectively promote the cell proliferation, and inhibit the cellular apoptosis of nonalcoholic fatty liver cells(PTang showed the best effect. Western blot results showed that Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could down-regulate the expressions of cleaved caspase-3, cleaved caspase-8, cleaved caspase-9 and Bax proteins, and up-regulate the expressions of PCNA and Bcl-2 proteins of nonalcoholic fatty liver cells. And Fuzi Lizhong Tang showed the best effect. In conclusion, all of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could effectively promote the cell

Arsenic induced apoptosis in rat liver following repeated 60 days exposure

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Bashir, Somia; Sharma, Yukti; Irshad, M.; Nag, T.C.; Tiwari, Monica; Kabra, M.; Dogra, T.D.

2006-01-01

Background: Accumulation of the wide spread environmental toxin arsenic in liver results in hepatotoxcity. Exposure to arsenite and other arsenicals has been previously shown to induce apoptosis in certain tumor cell lines at low (1-3 μM) concentration. Aim: The present study was focused to elucidate the role of free radicals in arsenic toxicity and to investigate the nature of in vivo sodium arsenite induced cell death in liver. Methods: Male wistar rats were exposed to arsenite at three different doses of 0.05, 2.5 and 5 mg/l for 60 days. Oxidative stress in liver was measured by estimating pro-oxidant and antioxidant activity in liver. Histopathological examination of liver was carried out by light and transmission electron microscopy. Analysis of DNA fragmentation by gel electrophoresis was used to identify apoptosis after the exposure. Terminal deoxy-nucleotidyl transferase mediated dUTP Nick end-labeling (TUNEL) assay was used to qualify and quantify apoptosis. Results: A significant increase in cytochrome-P450 and lipid peroxidation accompanied with a significant alteration in the activity of many of the antioxidants was observed, all suggestive of arsenic induced oxidative stress. Histopathological examination under light and transmission electron microscope suggested a combination of ongoing necrosis and apoptosis. DNA-TUNEL showed an increase in apoptotic cells in liver. Agarose gel electrophoresis of DNA of hepatocytes resulted in a characteristic ladder pattern. Conclusion: Chronic arsenic administration induces a specific pattern of apoptosis called post-mitotic apoptosis

Andrographis paniculata leaf extract prevents thioacetamide-induced liver cirrhosis in rats.

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Daleya Abdulaziz Bardi

Full Text Available This study investigated the hepatoprotective effects of ethanolic Andrographis paniculata leaf extract (ELAP on thioacetamide-induced hepatotoxicity in rats. An acute toxicity study proved that ELAP is not toxic in rats. To examine the effects of ELAP in vivo, male Sprague Dawley rats were given intraperitoneal injections of vehicle 10% Tween-20, 5 mL/kg (normal control or 200 mg/kg TAA thioacetamide (to induce liver cirrhosis three times per week. Three additional groups were treated with thioacetamide plus daily oral silymarin (50 mg/kg or ELAP (250 or 500 mg/kg. Liver injury was assessed using biochemical tests, macroscopic and microscopic tissue analysis, histopathology, and immunohistochemistry. In addition, HepG2 and WRL-68 cells were treated in vitro with ELAP fractions to test cytotoxicity. Rats treated with ELAP exhibited significantly lower liver/body weight ratios and smoother, more normal liver surfaces compared with the cirrhosis group. Histopathology using Hematoxylin and Eosin along with Masson's Trichrome stain showed minimal disruption of hepatic cellular structure, minor fibrotic septa, a low degree of lymphocyte infiltration, and minimal collagen deposition after ELAP treatment. Immunohistochemistry indicated that ELAP induced down regulation of proliferating cell nuclear antigen. Also, hepatic antioxidant enzymes and oxidative stress parameters in ELAP-treated rats were comparable to silymarin-treated rats. ELAP administration reduced levels of altered serum liver biomarkers. ELAP fractions were non-cytotoxic to WRL-68 cells, but possessed anti-proliferative activity on HepG2 cells, which was confirmed by a significant elevation of lactate dehydrogenase, reactive oxygen species, cell membrane permeability, cytochrome c, and caspase-8,-9, and, -3/7 activity in HepG2 cells. A reduction of mitochondrial membrane potential was also detected in ELAP-treated HepG2 cells. The hepatoprotective effect of 500 mg/kg of ELAP is proposed

Andrographis paniculata leaf extract prevents thioacetamide-induced liver cirrhosis in rats.

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Abdulaziz Bardi, Daleya; Halabi, Mohammed Farouq; Hassandarvish, Pouya; Rouhollahi, Elham; Paydar, Mohammadjavad; Moghadamtousi, Soheil Zorofchian; Al-Wajeeh, Nahla Saeed; Ablat, Abdulwali; Abdullah, Nor Azizan; Abdulla, Mahmood Ameen

2014-01-01

This study investigated the hepatoprotective effects of ethanolic Andrographis paniculata leaf extract (ELAP) on thioacetamide-induced hepatotoxicity in rats. An acute toxicity study proved that ELAP is not toxic in rats. To examine the effects of ELAP in vivo, male Sprague Dawley rats were given intraperitoneal injections of vehicle 10% Tween-20, 5 mL/kg (normal control) or 200 mg/kg TAA thioacetamide (to induce liver cirrhosis) three times per week. Three additional groups were treated with thioacetamide plus daily oral silymarin (50 mg/kg) or ELAP (250 or 500 mg/kg). Liver injury was assessed using biochemical tests, macroscopic and microscopic tissue analysis, histopathology, and immunohistochemistry. In addition, HepG2 and WRL-68 cells were treated in vitro with ELAP fractions to test cytotoxicity. Rats treated with ELAP exhibited significantly lower liver/body weight ratios and smoother, more normal liver surfaces compared with the cirrhosis group. Histopathology using Hematoxylin and Eosin along with Masson's Trichrome stain showed minimal disruption of hepatic cellular structure, minor fibrotic septa, a low degree of lymphocyte infiltration, and minimal collagen deposition after ELAP treatment. Immunohistochemistry indicated that ELAP induced down regulation of proliferating cell nuclear antigen. Also, hepatic antioxidant enzymes and oxidative stress parameters in ELAP-treated rats were comparable to silymarin-treated rats. ELAP administration reduced levels of altered serum liver biomarkers. ELAP fractions were non-cytotoxic to WRL-68 cells, but possessed anti-proliferative activity on HepG2 cells, which was confirmed by a significant elevation of lactate dehydrogenase, reactive oxygen species, cell membrane permeability, cytochrome c, and caspase-8,-9, and, -3/7 activity in HepG2 cells. A reduction of mitochondrial membrane potential was also detected in ELAP-treated HepG2 cells. The hepatoprotective effect of 500 mg/kg of ELAP is proposed to result from

Bioengineered Liver Models for Drug Testing and Cell Differentiation Studies

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Gregory H. Underhill

2018-01-01

Full Text Available In vitro models of the human liver are important for the following: (1 mitigating the risk of drug-induced liver injury to human beings, (2 modeling human liver diseases, (3 elucidating the role of single and combinatorial microenvironmental cues on liver cell function, and (4 enabling cell-based therapies in the clinic. Methods to isolate and culture primary human hepatocytes (PHHs, the gold standard for building human liver models, were developed several decades ago; however, PHHs show a precipitous decline in phenotypic functions in 2-dimensional extracellular matrix–coated conventional culture formats, which does not allow chronic treatment with drugs and other stimuli. The development of several engineering tools, such as cellular microarrays, protein micropatterning, microfluidics, biomaterial scaffolds, and bioprinting, now allow precise control over the cellular microenvironment for enhancing the function of both PHHs and induced pluripotent stem cell–derived human hepatocyte-like cells; long-term (4+ weeks stabilization of hepatocellular function typically requires co-cultivation with liver-derived or non–liver-derived nonparenchymal cell types. In addition, the recent development of liver organoid culture systems can provide a strategy for the enhanced expansion of therapeutically relevant cell types. Here, we discuss advances in engineering approaches for constructing in vitro human liver models that have utility in drug screening and for determining microenvironmental determinants of liver cell differentiation/function. Design features and validation data of representative models are presented to highlight major trends followed by the discussion of pending issues that need to be addressed. Overall, bioengineered liver models have significantly advanced our understanding of liver function and injury, which will prove useful for drug development and ultimately cell-based therapies.

Nrf2 activation prevents cadmium-induced acute liver injury

International Nuclear Information System (INIS)

Wu, Kai C.; Liu, Jie J.; Klaassen, Curtis D.

2012-01-01

Oxidative stress plays an important role in cadmium-induced liver injury. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that up-regulates cytoprotective genes in response to oxidative stress. To investigate the role of Nrf2 in cadmium-induced hepatotoxicity, Nrf2-null mice, wild-type mice, kelch-like ECH-associated protein 1-knockdown (Keap1-KD) mice with enhanced Nrf2, and Keap1-hepatocyte knockout (Keap1-HKO) mice with maximum Nrf2 activation were treated with cadmium chloride (3.5 mg Cd/kg, i.p.). Blood and liver samples were collected 8 h thereafter. Cadmium increased serum alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) activities, and caused extensive hepatic hemorrhage and necrosis in the Nrf2-null mice. In contrast, Nrf2-enhanced mice had lower serum ALT and LDH activities and less morphological alternations in the livers than wild-type mice. H 2 DCFDA (2′,7′-dichlorodihydrofluoresein diacetate) staining of primary hepatocytes isolated from the four genotypes of mice indicated that oxidative stress was higher in Nrf2-null cells, and lower in Nrf2-enhanced cells than in wild-type cells. To further investigate the mechanism of the protective effect of Nrf2, mRNA of metallothionein (MT) and other cytoprotective genes were determined. Cadmium markedly induced MT-1 and MT-2 in livers of all four genotypes of mice. In contrast, genes involved in glutathione synthesis and reducing reactive oxygen species, including glutamate-cysteine ligase (Gclc), glutathione peroxidase-2 (Gpx2), and sulfiredoxin-1 (Srxn-1) were only induced in Nrf2-enhanced mice, but not in Nrf2-null mice. In conclusion, the present study shows that Nrf2 activation prevents cadmium-induced oxidative stress and liver injury through induction of genes involved in antioxidant defense rather than genes that scavenge Cd. -- Highlights: ► Cadmium caused extensive hepatic hemorrhage and necrosis in Nrf2-null mice. ► Keap1-KD and Keap1-HKO mice were

Nrf2 activation prevents cadmium-induced acute liver injury

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Wu, Kai C. [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Liu, Jie J. [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Klaassen, Curtis D., E-mail: cklaasse@kumc.edu [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States)

2012-08-15

Oxidative stress plays an important role in cadmium-induced liver injury. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that up-regulates cytoprotective genes in response to oxidative stress. To investigate the role of Nrf2 in cadmium-induced hepatotoxicity, Nrf2-null mice, wild-type mice, kelch-like ECH-associated protein 1-knockdown (Keap1-KD) mice with enhanced Nrf2, and Keap1-hepatocyte knockout (Keap1-HKO) mice with maximum Nrf2 activation were treated with cadmium chloride (3.5 mg Cd/kg, i.p.). Blood and liver samples were collected 8 h thereafter. Cadmium increased serum alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) activities, and caused extensive hepatic hemorrhage and necrosis in the Nrf2-null mice. In contrast, Nrf2-enhanced mice had lower serum ALT and LDH activities and less morphological alternations in the livers than wild-type mice. H{sub 2}DCFDA (2′,7′-dichlorodihydrofluoresein diacetate) staining of primary hepatocytes isolated from the four genotypes of mice indicated that oxidative stress was higher in Nrf2-null cells, and lower in Nrf2-enhanced cells than in wild-type cells. To further investigate the mechanism of the protective effect of Nrf2, mRNA of metallothionein (MT) and other cytoprotective genes were determined. Cadmium markedly induced MT-1 and MT-2 in livers of all four genotypes of mice. In contrast, genes involved in glutathione synthesis and reducing reactive oxygen species, including glutamate-cysteine ligase (Gclc), glutathione peroxidase-2 (Gpx2), and sulfiredoxin-1 (Srxn-1) were only induced in Nrf2-enhanced mice, but not in Nrf2-null mice. In conclusion, the present study shows that Nrf2 activation prevents cadmium-induced oxidative stress and liver injury through induction of genes involved in antioxidant defense rather than genes that scavenge Cd. -- Highlights: ► Cadmium caused extensive hepatic hemorrhage and necrosis in Nrf2-null mice. ► Keap1-KD and Keap1-HKO mice

A preliminary study for constructing a bioartificial liver device with induced pluripotent stem cell-derived hepatocytes

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Iwamuro Masaya

2012-12-01

Full Text Available Abstract Background Bioartificial liver systems, designed to support patients with liver failure, are composed of bioreactors and functional hepatocytes. Immunological rejection of the embedded hepatocytes by the host immune system is a serious concern that crucially degrades the performance of the device. Induced pluripotent stem (iPS cells are considered a desirable source for bioartificial liver systems, because patient-derived iPS cells are free from immunological rejection. The purpose of this paper was to test the feasibility of a bioartificial liver system with iPS cell-derived hepatocyte-like cells. Methods Mouse iPS cells were differentiated into hepatocyte-like cells by a multi-step differentiation protocol via embryoid bodies and definitive endoderm. Differentiation of iPS cells was evaluated by morphology, PCR assay, and functional assays. iPS cell-derived hepatocyte-like cells were cultured in a bioreactor module with a pore size of 0.2 μm for 7 days. The amount of albumin secreted into the circulating medium was analyzed by ELISA. Additionally, after a 7-day culture in a bioreactor module, cells were observed by a scanning electron microscope. Results At the final stage of the differentiation program, iPS cells changed their morphology to a polygonal shape with two nucleoli and enriched cytoplasmic granules. Transmission electron microscope analysis revealed their polygonal shape, glycogen deposition in the cytoplasm, microvilli on their surfaces, and a duct-like arrangement. PCR analysis showed increased expression of albumin mRNA over the course of the differentiation program. Albumin and urea production was also observed. iPS-Heps culture in bioreactor modules showed the accumulation of albumin in the medium for up to 7 days. Scanning electron microscopy revealed the attachment of cell clusters to the hollow fibers of the module. These results indicated that iPS cells were differentiated into hepatocyte-like cells after culture

Nonacetaminophen Drug-Induced Acute Liver Failure.

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Thomas, Arul M; Lewis, James H

2018-05-01

Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival. Copyright © 2018 Elsevier Inc. All rights reserved.

Cell-swelling-induced taurine release from isolated perfused rat liver

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Brand, H. S.; Meijer, A. J.; Gustafson, L. A.; Jörning, G. G.; Leegwater, A. C.; Maas, M. A.; Chamuleau, R. A.

1994-01-01

Astrocytes and lymphocytes are able to release significant amounts of taurine during periods of hypotonicity to reduce the increase in cell volume. To investigate this mechanism in the liver, we studied the release of free amino acids from isolated perfused rat liver during hypotonicity. The

Human Liver Cells Expressing Albumin and Mesenchymal Characteristics Give Rise to Insulin-Producing Cells

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Irit Meivar-Levy

2011-01-01

Full Text Available Activation of the pancreatic lineage in the liver has been suggested as a potential autologous cell replacement therapy for diabetic patients. Transcription factors-induced liver-to-pancreas reprogramming has been demonstrated in numerous species both in vivo and in vitro. However, human-derived liver cells capable of acquiring the alternate pancreatic repertoire have never been characterized. It is yet unknown whether hepatic-like stem cells or rather adult liver cells give rise to insulin-producing cells. Using an in vitro experimental system, we demonstrate that proliferating adherent human liver cells acquire mesenchymal-like characteristics and a considerable level of cellular plasticity. However, using a lineage-tracing approach, we demonstrate that insulin-producing cells are primarily generated in cells enriched for adult hepatic markers that coexpress both albumin and mesenchymal markers. Taken together, our data suggest that adult human hepatic tissue retains a substantial level of developmental plasticity, which could be exploited in regenerative medicine approaches.

Heterogenic transplantation of bone marrow-derived rhesus macaque mesenchymal stem cells ameliorates liver fibrosis induced by carbon tetrachloride in mouse

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Xufeng Fu

2018-02-01

Full Text Available Liver fibrosis is a disease that causes high morbidity and has become a major health problem. Liver fibrosis can lead to the end stage of liver diseases (livercirrhosisand hepatocellularcarcinoma. Currently, liver transplantation is the only effective treatment for end-stage liver disease. However, the shortage of organ donors, high cost of medical surgery, immunological rejection and transplantation complications severely hamper liver transplantation therapy. Mesenchymal stem cells (MSCs have been regarded as promising cells for clinical applications in stem cell therapy in the treatment of liver diseases due to their unique multipotent differentiation capacity, immunoregulation and paracrine effects. Although liver fibrosis improvements by MSC transplantation in preclinical experiments as well as clinical trials have been reported, the in vivo fate of MSCs after transportation and their therapeutic mechanisms remain unclear. In this present study, we isolated MSCs from the bone marrow of rhesus macaques. The cells exhibited typical MSC markers and could differentiate into chondrocytes, osteocytes, and adipocytes, which were not affected by labeling with enhanced green fluorescent protein (EGFP. The harvested MSCs respond to interferon-γ stimulation and have the ability to inhibit lymphocyte proliferation in vitro. EGFP-labeled MSCs (1 × 106 cells were transplanted into mice with carbon tetrachloride-induced liver fibrosis via tail vein injection. The ability of the heterogenic MSC infusion to ameliorate liver fibrosis in mice was evaluated by a blood plasma chemistry index, pathological examination and liver fibrosis-associated gene expression. Additionally, a small number of MSCs that homed and engrafted in the mouse liver tissues were evaluated by immunofluorescence analysis. Our results showed that the transplantation of heterogenic MSCs derived from monkey bone marrow can be used to treat liver fibrosis in the mouse model and that the

Rapamycin Induces Heme Oxygenase-1 in Liver but Inhibits Bile Flow Recovery after Ischemia

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Kist, Alwine; Wakkie, Joris; Madu, Max; Versteeg, Ruth; ten Berge, Judith; Nikolic, Andrej; Nieuwenhuijs, Vincent B.; Porte, Robert J.; Padbury, Robert T. A.; Barritt, Greg J.

Background/Aims. Rapamycin, which is employed in the management of patients undergoing liver surgery, induces the synthesis of heme oxygenase-1 (HO-1) in some non-liver cell types. The aim was to investigate whether rapamycin can induce HO-1 expression in the liver, and to test the effects of

Increased Expression of Cytotoxic T-Lymphocyte-Associated Protein 4 by T Cells, Induced by B7 in Sera, Reduces Adaptive Immunity in Patients With Acute Liver Failure

DEFF Research Database (Denmark)

Khamri, Wafa; Abeles, Robin D; Hou, Tie Zheng

2017-01-01

, hepatic sinusoidal endothelial cells, and biliary epithelial cells from healthy or diseased liver tissues. We also measured levels of soluble B7 serum samples from patients and controls, and mice with acetaminophen-induced liver injury using enzyme-linked immunosorbent assays. RESULTS: Peripheral blood...... mice with acetaminophen-induced liver injury contained high levels of soluble B7 compared to sera from mice without liver injury. Plasma exchange reduced circulating levels of soluble B7 in patients with ALF and expression of CTLA4 on T cells. CONCLUSIONS: Peripheral CD4+ T cells from patients with ALF......BACKGROUND & AIMS: Patients with acute liver failure (ALF) have defects in innate immune responses to microbes (immune paresis) and are susceptible to sepsis. Cytotoxic T-lymphocyte-associated protein 4 (CTLA4), which interacts with the membrane receptor B7 (also called CD80 and CD86...

Increased Expression of Cytotoxic T-Lymphocyte-Associated Protein 4 by T Cells, Induced by B7 in Sera, Reduces Adaptive Immunity in Patients With Acute Liver Failure

DEFF Research Database (Denmark)

Khamri, Wafa; Abeles, Robin D; Hou, Tie Zheng

2017-01-01

, hepatic sinusoidal endothelial cells, and biliary epithelial cells from healthy or diseased liver tissues. We also measured levels of soluble B7 serum samples from patients and controls, and mice with acetaminophen-induced liver injury using enzyme-linked immunosorbent assays. RESULTS: Peripheral blood...... were found to have increased concentrations of soluble B7 compared to sera from controls. Necrotic human primary hepatocytes exposed to acetaminophen, but not hepatic sinusoidal endothelial cells and biliary epithelial cells from patients with ALF, secreted high levels of soluble B7. Sera from mice...... with acetaminophen-induced liver injury contained high levels of soluble B7 compared to sera from mice without liver injury. Plasma exchange reduced circulating levels of soluble B7 in patients with ALF and expression of CTLA4 on T cells. CONCLUSIONS: Peripheral CD4+T cells from patients with ALF have increased...

Quercetin prevents pyrrolizidine alkaloid clivorine-induced liver injury in mice by elevating body defense capacity.

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Lili Ji

Full Text Available Quercetin is a plant-derived flavonoid that is widely distributed in nature. The present study is designed to analyze the underlying mechanism in the protection of quercetin against pyrrolizidine alkaloid clivorine-induced acute liver injury in vivo. Serum transaminases, total bilirubin analysis, and liver histological evaluation demonstrated the protection of quercetin against clivorine-induced liver injury. Terminal dUTP nick end-labeling assay demonstrated that quercetin reduced the increased amount of liver apoptotic cells induced by clivorine. Western-blot analysis of caspase-3 showed that quercetin inhibited the cleaved activation of caspase-3 induced by clivorine. Results also showed that quercetin reduced the increase in liver glutathione and lipid peroxidative product malondialdehyde induced by clivorine. Quercetin reduced the enhanced liver immunohistochemical staining for 4-hydroxynonenal induced by clivorine. Results of the Mouse Stress and Toxicity PathwayFinder RT2 Profiler PCR Array demonstrated that the expression of genes related with oxidative or metabolic stress and heat shock was obviously altered after quercetin treatment. Some of the alterations were confirmed by real-time PCR. Our results demonstrated that quercetin prevents clivorine-induced acute liver injury in vivo by inhibiting apoptotic cell death and ameliorating oxidative stress injury. This protection may be caused by the elevation of the body defense capacity induced by quercetin.

Quercetin Prevents Pyrrolizidine Alkaloid Clivorine-Induced Liver Injury in Mice by Elevating Body Defense Capacity

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Ji, Lili; Ma, Yibo; Wang, Zaiyong; Cai, Zhunxiu; Pang, Chun; Wang, Zhengtao

2014-01-01

Quercetin is a plant-derived flavonoid that is widely distributed in nature. The present study is designed to analyze the underlying mechanism in the protection of quercetin against pyrrolizidine alkaloid clivorine-induced acute liver injury in vivo. Serum transaminases, total bilirubin analysis, and liver histological evaluation demonstrated the protection of quercetin against clivorine-induced liver injury. Terminal dUTP nick end-labeling assay demonstrated that quercetin reduced the increased amount of liver apoptotic cells induced by clivorine. Western-blot analysis of caspase-3 showed that quercetin inhibited the cleaved activation of caspase-3 induced by clivorine. Results also showed that quercetin reduced the increase in liver glutathione and lipid peroxidative product malondialdehyde induced by clivorine. Quercetin reduced the enhanced liver immunohistochemical staining for 4-hydroxynonenal induced by clivorine. Results of the Mouse Stress and Toxicity PathwayFinder RT2 Profiler PCR Array demonstrated that the expression of genes related with oxidative or metabolic stress and heat shock was obviously altered after quercetin treatment. Some of the alterations were confirmed by real-time PCR. Our results demonstrated that quercetin prevents clivorine-induced acute liver injury in vivo by inhibiting apoptotic cell death and ameliorating oxidative stress injury. This protection may be caused by the elevation of the body defense capacity induced by quercetin. PMID:24905073

Garcinia dulcis Fruit Extract Induced Cytotoxicity and Apoptosis in HepG2 Liver Cancer Cell Line

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Mohd Fadzelly Abu Bakar

2015-01-01

Full Text Available Garcinia dulcis or locally known in Malaysia as “mundu” belongs to the family of Clusiaceae. The study was conducted to investigate the anticancer potential of different parts of G. dulcis fruit extracts and their possible mechanism of action in HepG2 liver cancer cell line. MTT assay showed that the peel, flesh, and seed extracts of G. dulcis induced cytotoxicity in HepG2 cell line with IC50 values of 46.33 ± 4.51, 38.33 ± 3.51, and 7.5 ± 2.52 µg/mL, respectively. The flesh extract of G. dulcis induced cell cycle arrest at sub-G1 (apoptosis phase in a time-dependent manner. Staining with Annexin V-FITC and propidium iodide showed that 41.2% of the cell population underwent apoptosis after 72 hours of exposure of the HepG2 cell line to G. dulcis flesh extract. Caspase-3 has been shown to be activated which finally leads to the death of HepG2 cell (apoptosis. GC-MS analysis showed that the highest percentage of compound identified in the extract of G. dulcis flesh was hydroxymethylfurfural and 3-methyl-2,5-furandione, together with xanthones and flavonoids (based on literature, could synergistically contribute to the observed effects. This finding suggested that the flesh extract of G. dulcis has its own potential as cancer chemotherapeutic agent against liver cancer cell.

Maitotoxin Is a Potential Selective Activator of the Endogenous Transient Receptor Potential Canonical Type 1 Channel in Xenopus laevis Oocytes

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Pedro L. Flores

2017-06-01

Full Text Available Maitotoxin (MTX is the most potent marine toxin known to date. It is responsible for a particular human intoxication syndrome called ciguatera fish poisoning (CFP. Several reports indicate that MTX is an activator of non-selective cation channels (NSCC in different cell types. The molecular identity of these channels is still an unresolved topic, and it has been proposed that the transient receptor potential (TRP channels are involved in this effect. In Xenopus laevis oocytes, MTX at picomolar (pM concentrations induces the activation of NSCC with functional and pharmacological properties that resemble the activity of TRP channels. The purpose of this study was to characterize the molecular identity of the TRP channel involved in the MTX response, using the small interference RNA (siRNA approach and the two-electrode voltage-clamp technique (TEVC. The injection of a specifically designed siRNA to silence the transient receptor potential canonical type 1 (TRPC1 protein expression abolished the MTX response. MTX had no effect on oocytes, even at doses 20-fold higher compared to cells without injection. Total mRNA and protein levels of TRPC1 were notably diminished. The TRPC4 siRNA did not change the MTX effect, even though it was important to note that the protein level was reduced by the silencing of TRPC4. Our results suggest that MTX could be a selective activator of TRPC1 channels in X. laevis oocytes and a useful pharmacological tool for further studies on these TRP channels.

Time-course of cadmium-induced acute hepatotoxicity in the rat liver: the role of apoptosis

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Tzirogiannis, Konstantinos N.; Panoutsopoulos, Georgios I.; Hereti, Rosa I.; Alexandropoulou, Katerina N.; Basayannis, Aristidis C.; Mykoniatis, Michael G. [Department of Experimental Pharmacology, Medical School, Athens University, 75 Mikras Asias St., 115 27, Athens (Greece); Demonakou, Maria D. [Histopathology Laboratory, Sismanoglion G.D. Hospital, Sismanogliou 1, Marousi, Attiki 151 27 (Greece)

2003-12-01

Exposure to toxic metals and pollutants is a major environmental problem. Cadmium is a metal causing acute hepatic injury but the mechanism of this phenomenon is poorly understood. In the present study, we investigated the mechanism and time-course of cadmium-induced liver injury in rats, with emphasis being placed on apoptosis in parenchymal and nonparenchymal liver cells. Cadmium (3.5 mg/kg body weight) was injected intraperitoneally and the rats were killed 0, 9, 12, 16, 24, 48 and 60 h later. The extent of liver injury was evaluated for necrosis, apoptosis, peliosis, mitoses and inflammatory infiltration in hematoxylin-eosin-stained liver sections, and by assaying serum enzyme activities. The number of cells that died via apoptosis was quantified by TUNEL assay. The identification of nonparenchymal liver cells and activated Kupffer cells was performed histochemically. Liver regeneration was evaluated by assaying the activity of liver thymidine kinase and by the rate of {sup 3}H-thymidine incorporation into DNA. Both cadmium-induced necrotic cell death and parenchymal cell apoptosis showed a biphasic elevation at 12 and 48 h and peaked at 48 and 12 h, respectively. Nonparenchymal cell apoptosis peaked at 48 h. Peliosis hepatis, another characteristic form of liver injury, was first observed at 16 h and, at all time points, closely correlated with the apoptotic index of nonparenchymal liver cells, where the lesion was also maximial at 48 h. Kupffer cell activation and neutrophil infiltration were minimal for all time points examined. Based on thymidine kinase activity, liver regeneration was found to discern a classic biphasic peak pattern at 12 and 48 h. It was very interesting to observe that cadmium-induced liver injury did not involve inflammation at any time point. Apoptosis seems to be a major mechanism for the removal of damaged cells, and constitutes the major type of cell death in nonparenchymal liver cells. Apoptosis of nonparenchymal cells is the basis

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

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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

Follicular helper T cells promote liver pathology in mice during Schistosoma japonicum infection.

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Xiaojun Chen

2014-05-01

Full Text Available Following Schistosoma japonicum (S. japonicum infection, granulomatous responses are induced by parasite eggs trapped in host organs, particular in the liver, during the acute stage of disease. While excessive liver granulomatous responses can lead to more severe fibrosis and circulatory impairment in chronically infected host. However, the exact mechanism of hepatic granuloma formation has remained obscure. In this study, we for the first time showed that follicular helper T (Tfh cells are recruited to the liver to upregulate hepatic granuloma formation and liver injury in S. japonicum-infected mice, and identified a novel function of macrophages in Tfh cell induction. In addition, our results showed that the generation of Tfh cells driven by macrophages is dependent on cell-cell contact and the level of inducible costimulator ligand (ICOSL on macrophages which is regulated by CD40-CD40L signaling. Our findings uncovered a previously unappreciated role for Tfh cells in liver pathology caused by S. japonicum infection in mice.

Rapid Extraction and Identification of Maitotoxin and Ciguatoxin-Like Toxins from Caribbean and Pacific Gambierdiscus Using a New Functional Bioassay

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Lewis, Richard J.; Inserra, Marco; Vetter, Irina; Holland, William C.; Hardison, D. Ransom; Tester, Patricia A.; Litaker, R. Wayne

2016-01-01

Background Ciguatera is a circumtropical disease produced by polyether sodium channel toxins (ciguatoxins) that enter the marine food chain and accumulate in otherwise edible fish. Ciguatoxins, as well as potent water-soluble polyethers known as maitotoxins, are produced by certain dinoflagellate species in the genus Gambierdiscus and Fukuyoa spp. in the Pacific but little is known of the potential of related Caribbean species to produce these toxins. Methods We established a simplified proce...

Acute Liver Injury Is Independent of B Cells or Immunoglobulin M.

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James A Richards

Full Text Available Acute liver injury is a clinically important pathology and results in the release of Danger Associated Molecular Patterns, which initiate an immune response. Withdrawal of the injurious agent and curtailing any pathogenic secondary immune response may allow spontaneous resolution of injury. The role B cells and Immunoglobulin M (IgM play in acute liver injury is largely unknown and it was proposed that B cells and/or IgM would play a significant role in its pathogenesis.Tissue from 3 models of experimental liver injury (ischemia-reperfusion injury, concanavalin A hepatitis and paracetamol-induced liver injury and patients transplanted following paracetamol overdose were stained for evidence of IgM deposition. Mice deficient in B cells (and IgM were used to dissect out the role B cells and/or IgM played in the development or resolution of injury. Serum transfer into mice lacking IgM was used to establish the role IgM plays in injury.Significant deposition of IgM was seen in the explanted livers of patients transplanted following paracetamol overdose as well as in 3 experimental models of acute liver injury (ischemia-reperfusion injury, concanavalin A hepatitis and paracetamol-induced liver injury. Serum transfer into IgM-deficient mice failed to reconstitute injury (p = 0.66, despite successful engraftment of IgM. Mice deficient in both T and B cells (RAG1-/- mice (p<0.001, but not B cell deficient (μMT mice (p = 0.93, were significantly protected from injury. Further interrogation with T cell deficient (CD3εKO mice confirmed that the T cell component is a key mediator of sterile liver injury. Mice deficient in B cells and IgM mice did not have a significant delay in resolution following acute liver injury.IgM deposition appears to be common feature of both human and murine sterile liver injury. However, neither IgM nor B cells, play a significant role in the development of or resolution from acute liver injury. T cells appear to be key

Advanced glycation end products promote ChREBP expression and cell proliferation in liver cancer cells by increasing reactive oxygen species.

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Chen, Hanbei; Li, Yakui; Zhu, Yemin; Wu, Lifang; Meng, Jian; Lin, Ning; Yang, Dianqiang; Li, Minle; Ding, WenJin; Tong, Xuemei; Su, Qing

2017-08-01

The aim of the study was to elucidate the mechanism by which advanced glycation end products (AGEs) promote cell proliferation in liver cancer cells.We treated liver cancer HepG2 cells with 200 mg/L AGEs or bovine serum albumin (BSA) and assayed for cell viability, cell cycle, and apoptosis. We performed real-time PCR and Western blot analysis for RNA and protein levels of carbohydrate responsive element-binding protein (ChREBP) in AGEs- or BSA-treated HepG2 cells. We analyzed the level of reactive oxygen species (ROS) in HepG2 cells treated with AGEs or BSA.We found that increased S-phase cell percentage and decreased apoptosis contributed to AGEs-induced liver cancer cell proliferation. Real-time PCR and Western blot analysis showed that AGEs stimulated RNA and protein levels of ChREBP, a transcription factor promoting glycolysis and maintaining cell proliferation in liver cancer cells. Intriguingly, the level of ROS was higher in AGEs-treated liver cancer cells. Treating liver cancer cells with antioxidant N-acetyl cystein (NAC) partly blocked AGEs-induced ChREBP expression and cell proliferation.Our results suggest that the AGEs-ROS-ChREBP pathway plays a critical role in promoting ChREBP expression and liver cancer cell proliferation.

Radio protective effect of black mulberry extract on radiation-induced damage in bone marrow cells and liver in the rat

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Ghasemnezhad Targhi, Reza; Homayoun, Mansour; Mansouri, Somaieh; Soukhtanloo, Mohammad; Soleymanifard, Shokouhozaman; Seghatoleslam, Masoumeh

2017-01-01

Ionizing radiation by producing free radicals induces tissue oxidative stress and has clastogenic and cytotoxic effects. The radio protective effect of black mulberry extract (BME) has been investigated on liver tissue and bone marrow cells in the rat. Intraperitoneal (ip) administration of 200 mg/kg BME three days before and three days after 3 Gy and 6 Gy gamma irradiation significantly reduced the frequencies of micro nucleated polychromatic erythrocytes (MnPCEs) and micro nucleated norm chromatic erythrocyte (MnNCEs) and increased PCE/PCE+NCE ratio in rat bone marrow compared to the non-treated irradiated groups. Moreover, this concentration of BME extract decreased the level of malondialdehyde (MDA) and superoxide dismutase (SOD), as well as enhanced the total thiol content and catalase activity in rat's liver compared to the non-treated irradiated groups. It seems that BME extract with antioxidant activity reduced the genotoxicity and cytotoxicity induced by gamma irradiation in bone marrow cells and liver in the rat.

Diet-induced metabolic hamster model of nonalcoholic fatty liver disease

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Bhathena J

2011-06-01

Full Text Available Jasmine Bhathena, Arun Kulamarva, Christopher Martoni, Aleksandra Malgorzata Urbanska, Meenakshi Malhotra, Arghya Paul, Satya PrakashBiomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Artificial Cells and Organs Research Centre, Faculty of Medicine, McGill University, Montreal, Québec, CanadaBackground: Obesity, hypercholesterolemia, elevated triglycerides, and type 2 diabetes are major risk factors for metabolic syndrome. Hamsters, unlike rats or mice, respond well to diet-induced obesity, increase body mass and adiposity on group housing, and increase food intake due to social confrontation-induced stress. They have a cardiovascular and hepatic system similar to that of humans, and can thus be a useful model for human pathophysiology.Methods: Experiments were planned to develop a diet-induced Bio F1B Golden Syrian hamster model of dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hamsters were fed a normal control diet, a high-fat/high-cholesterol diet, a high-fat/high-cholesterol/methionine-deficient/choline-devoid diet, and a high-fat/high-cholesterol/choline-deficient diet. Serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, glucose, atherogenic index, and body weight were quantified biweekly. Fat deposition in the liver was observed and assessed following lipid staining with hematoxylin and eosin and with oil red O.Results: In this study, we established a diet-induced Bio F1B Golden Syrian hamster model for studying dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hyperlipidemia and elevated serum glucose concentrations were induced using this diet. Atherogenic index was elevated, increasing the risk for a cardiovascular event. Histological analysis of liver specimens at the end of four weeks showed increased fat deposition in the liver of animals fed

CD205-TLR9-IL-12 axis contributes to CpG-induced oversensitive liver injury in HBsAg transgenic mice by promoting the interaction of NKT cells with Kupffer cells.

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Hou, Xin; Hao, Xiaolei; Zheng, Meijuan; Xu, Congfei; Wang, Jun; Zhou, Rongbin; Tian, Zhigang

2017-08-01

Gut-derived bacterial products contribute to liver inflammation and injury during chronic hepatitis B virus infection; however, the underlying mechanisms remain obscure. In this study, hepatitis B surface antigen transgenic (HBs-Tg) mice and their wild-type (WT) control C57BL/6 mice were injected with CpG-oligodeoxynucleotides (ODNs) to mimic the translocation of gut microbial products into the systemic circulation. We found that, compared with the WT mice, the HBs-Tg mice were oversensitive to CpG-ODN-induced liver injury, which was dependent on natural killer T (NKT) cells. CpG-ODN injection enhanced the expression of Fas ligand (FasL) on NKT cells. In addition, hepatocytes from the HBs-Tg mice expressed higher levels of Fas than did those from the WT mice, which was further augmented by CpG-ODN. Interaction of Fas and FasL was involved in the cytotoxicity of NKT cells against hepatocytes in the HBs-Tg mice. Moreover, Kupffer cells in the HBs-Tg mice expressed higher levels of CD205 and produced greater amounts of interleukin (IL)-12 than did those in the WT mice. Finally, the depletion of Kupffer cells, neutralization of IL-12 or specific silencing of CD205 on Kupffer cells significantly inhibited CpG-ODN-induced liver injury and NKT activation in the HBs-Tg mice. Our data suggest that CD205-expressing Kupffer cells respond to CpG-ODNs and subsequently release IL-12 to promote NKT cell activation. Activated NKT cells induce liver damage through the Fas signaling pathway in HBs-Tg mice.

Fish oil prevents sucrose-induced fatty liver but exacerbates high-safflower oil-induced fatty liver in ddy mice.

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Yamazaki, Tomomi; Nakamori, Akiko; Sasaki, Eriko; Wada, Satoshi; Ezaki, Osamu

2007-12-01

Diets high in sucrose/fructose or fat can result in hepatic steatosis (fatty liver). We analyzed the effects of dietary fish oil on fatty liver induced by sucrose, safflower oil, and butter in ddY mice. In experiment I, mice were fed a high-starch diet [70 energy% (en%) starch] plus 20% (wt/wt) sucrose in the drinking water or fed a high-safflower oil diet (60 en%) for 11 weeks. As a control, mice were fed a high-starch diet with drinking water. Fish oil (10 en%) was either supplemented or not. Mice supplemented with sucrose or fed safflower oil showed a 1.7-fold or 2.2-fold increased liver triglyceride content, respectively, compared with that of control mice. Fish oil completely prevented sucrose-induced fatty liver, whereas it exacerbated safflower oil-induced fatty liver. Sucrose increased SREBP-1c and target gene messenger RNAs (mRNAs), and fish oil completely inhibited these increases. In experiment II, mice were fed a high-safflower oil or a high-butter diet, with or without fish oil supplementation. Fish oil exacerbated safflower oil-induced fatty liver but did not affect butter-induced fatty liver. Fish oil increased expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and target CD36 mRNA in safflower oil-fed mice. These increases were not observed in sucrose-supplemented or butter-fed mice. The effects of dietary fish oil on fatty liver differ according to the cause of fatty liver; fish oil prevents sucrose-induced fatty liver but exacerbates safflower oil-induced fatty liver. The exacerbation of fatty liver may be due, at least in part, to increased expression of liver PPARgamma.

Thyroid Hormone-Induced Cytosol-to-Nuclear Translocation of Rat Liver Nrf2 Is Dependent on Kupffer Cell Functioning

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Luis A. Videla

2012-01-01

Full Text Available L-3,3′,5-triiodothyronine (T3 administration upregulates nuclear factor-E2-related factor 2 (Nrf2 in rat liver, which is redox-sensitive transcription factor mediating cytoprotection. In this work, we studied the role of Kupffer cell respiratory burst activity, a process related to reactive oxygen species generation and liver homeostasis, in Nrf2 activation using the macrophage inactivator gadolinium chloride (GdCl3; 10 mg/kg i.v. 72 h before T3 [0.1 mg/kg i.p.] or NADPH oxidase inhibitor apocynin (1.5 mmol/L added to the drinking water for 7 days before T3, and determinations were performed 2 h after T3. T3 increased nuclear/cytosolic Nrf2 content ratio and levels of heme oxygenase 1 (HO-1, catalytic subunit of glutamate cysteine ligase, and thioredoxin (Western blot over control values, proteins whose gene transcription is induced by Nrf2. These changes were suppressed by GdCl3 treatment prior to T3, an agent-eliciting Kupffer-cell depletion, inhibition of colloidal carbon phagocytosis, and the associated respiratory burst activity, with enhancement in nuclear inhibitor of Nrf2 kelch-like ECH-associated protein 1 (Keap1/Nrf2 content ratios suggesting Nrf2 degradation. Under these conditions, T3-induced tumor necrosis factor-α (TNF-α response was eliminated by previous GdCl3 administration. Similar to GdCl3, apocynin given before T3 significantly reduced liver Nrf2 activation and HO-1 expression, a NADPH oxidase inhibitor eliciting abolishment of colloidal carbon-induced respiratory burst activity without altering carbon phagocytosis. It is concluded that Kupffer cell functioning is essential for upregulation of liver Nrf2-signaling pathway by T3. This contention is supported by suppression of the respiratory burst activity of Kupffer cells and the associated reactive oxygen species production by GdCl3 or apocynin given prior to T3, thus hindering Nrf2 activation.

The Role of Dendritic Cells in Fibrosis Progression in Nonalcoholic Fatty Liver Disease

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Paloma Almeda-Valdes

2015-01-01

Full Text Available Nonalcoholic fatty liver disease (NAFLD is the most frequent cause of chronic liver disease. NAFLD encompasses a wide range of pathologies, from simple steatosis to steatosis with inflammation to fibrosis. The pathogenesis of NAFLD progression has not been completely elucidated, and different liver cells could be implicated. This review focuses on the current evidence of the role of liver dendritic cells (DCs in the progression from NAFLD to fibrosis. Liver DCs are a heterogeneous population of hepatic antigen-presenting cells; their main function is to induce T-cell mediated immunity by antigen processing and presentation to T cells. During the steady state liver DCs are immature and tolerogenic. However, in an environment of chronic inflammation, DCs are transformed to potent inducers of immune responses. There is evidence about the role of DC in liver fibrosis, but it is not clearly understood. Interestingly, there might be a link between lipid metabolism and DC function, suggesting that immunogenic DCs are associated with liver lipid storage, representing a possible pathophysiological mechanism in NAFLD development. A better understanding of the interaction between inflammatory pathways and the different cell types and the effect on the progression of NAFLD is of great relevance.

Hepatocytes polyploidization and cell cycle control in liver physiopathology.

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Gentric, Géraldine; Desdouets, Chantal; Celton-Morizur, Séverine

2012-01-01

Most cells in mammalian tissues usually contain a diploid complement of chromosomes. However, numerous studies have demonstrated a major role of "diploid-polyploid conversion" during physiopathological processes in several tissues. In the liver parenchyma, progressive polyploidization of hepatocytes takes place during postnatal growth. Indeed, at the suckling-weaning transition, cytokinesis failure events induce the genesis of binucleated tetraploid liver cells. Insulin signalling, through regulation of the PI3K/Akt signalling pathway, is essential in the establishment of liver tetraploidization by controlling cytoskeletal organisation and consequently mitosis progression. Liver cell polyploidy is generally considered to indicate terminal differentiation and senescence, and both lead to a progressive loss of cell pluripotency associated to a markedly decreased replication capacity. Although adult liver is a quiescent organ, it retains a capacity to proliferate and to modulate its ploidy in response to various stimuli or aggression (partial hepatectomy, metabolic overload (i.e., high copper and iron hepatic levels), oxidative stress, toxic insult, and chronic hepatitis etc.). Here we review the mechanisms and functional consequences of hepatocytes polyploidization during normal and pathological liver growth.

Hepatocytes Polyploidization and Cell Cycle Control in Liver Physiopathology

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Géraldine Gentric

2012-01-01

Full Text Available Most cells in mammalian tissues usually contain a diploid complement of chromosomes. However, numerous studies have demonstrated a major role of “diploid-polyploid conversion” during physiopathological processes in several tissues. In the liver parenchyma, progressive polyploidization of hepatocytes takes place during postnatal growth. Indeed, at the suckling-weaning transition, cytokinesis failure events induce the genesis of binucleated tetraploid liver cells. Insulin signalling, through regulation of the PI3K/Akt signalling pathway, is essential in the establishment of liver tetraploidization by controlling cytoskeletal organisation and consequently mitosis progression. Liver cell polyploidy is generally considered to indicate terminal differentiation and senescence, and both lead to a progressive loss of cell pluripotency associated to a markedly decreased replication capacity. Although adult liver is a quiescent organ, it retains a capacity to proliferate and to modulate its ploidy in response to various stimuli or aggression (partial hepatectomy, metabolic overload (i.e., high copper and iron hepatic levels, oxidative stress, toxic insult, and chronic hepatitis etc.. Here we review the mechanisms and functional consequences of hepatocytes polyploidization during normal and pathological liver growth.

A small population of liver endothelial cells undergoes endothelial-to-mesenchymal transition in response to chronic liver injury.

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Ribera, Jordi; Pauta, Montse; Melgar-Lesmes, Pedro; Córdoba, Bernat; Bosch, Anna; Calvo, Maria; Rodrigo-Torres, Daniel; Sancho-Bru, Pau; Mira, Aurea; Jiménez, Wladimiro; Morales-Ruiz, Manuel

2017-11-01

Rising evidence points to endothelial-to-mesenchymal transition (EndMT) as a significant source of the mesenchymal cell population in fibrotic diseases. In this context, we hypothesized that liver endothelial cells undergo EndMT during fibrosis progression. Cirrhosis in mice was induced by CCl 4 A transgenic mouse expressing a red fluorescent protein reporter under the control of Tie2 promoter (Tie2-tdTomato) was used to trace the acquisition of EndMT. Sinusoidal vascular connectivity was evaluated by intravital microscopy and high-resolution three-dimensional confocal microscopy. A modest but significant fraction of liver endothelial cells from both cirrhotic patients and CCl 4 -treated Tie2-tdTomato mice acquired an EndMT phenotype characterized by the coexpression of CD31 and α-smooth muscle actin, compared with noncirrhotic livers. Bone morphogenetic protein-7 (BMP-7) inhibited the acquisition of EndMT induced by transforming growth factor-β1 (TGF-β1) treatment in cultured primary mouse liver endothelial cells from control mice. EndMT was also reduced significantly in vivo in cirrhotic Tie2-tdTomato mice treated intraperitoneally with BMP-7 compared with untreated mice (1.9 ± 0.2 vs. 3.8 ± 0.3%, respectively; P livers correlated with a significant decrease in liver fibrosis ( P livers in both animal models and patients. BMP-7 treatment decreases the occurrence of the EndMT phenotype and has a positive impact on the severity of disease by reducing fibrosis and sinusoidal vascular disorganization. NEW & NOTEWORTHY A subpopulation of liver endothelial cells from cirrhotic patients and mice with liver fibrosis undergoes endothelial-to-mesenchymal transition. Liver endothelial cells from healthy mice could transition into a mesenchymal phenotype in culture in response to TGF-β1 treatment. Fibrotic livers treated chronically with BMP-7 showed lower EndMT acquisition, reduced fibrosis, and improved vascular organization. Copyright © 2017 the American

Uridine prevents fenofibrate-induced fatty liver.

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Thuc T Le

Full Text Available Uridine, a pyrimidine nucleoside, can modulate liver lipid metabolism although its specific acting targets have not been identified. Using mice with fenofibrate-induced fatty liver as a model system, the effects of uridine on liver lipid metabolism are examined. At a daily dosage of 400 mg/kg, fenofibrate treatment causes reduction of liver NAD(+/NADH ratio, induces hyper-acetylation of peroxisomal bifunctional enzyme (ECHD and acyl-CoA oxidase 1 (ACOX1, and induces excessive accumulation of long chain fatty acids (LCFA and very long chain fatty acids (VLCFA. Uridine co-administration at a daily dosage of 400 mg/kg raises NAD(+/NADH ratio, inhibits fenofibrate-induced hyper-acetylation of ECHD, ACOX1, and reduces accumulation of LCFA and VLCFA. Our data indicates a therapeutic potential for uridine co-administration to prevent fenofibrate-induced fatty liver.

Sulforaphane Protects the Liver against CdSe Quantum Dot-Induced Cytotoxicity.

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Wei Wang

Full Text Available The potential cytotoxicity of cadmium selenide (CdSe quantum dots (QDs presents a barrier to their use in biomedical imaging or as diagnostic and therapeutic agents. Sulforaphane (SFN is a chemoprotective compound derived from cruciferous vegetables which can up-regulate antioxidant enzymes and induce apoptosis and autophagy. This study reports the effects of SFN on CdSe QD-induced cytotoxicity in immortalised human hepatocytes and in the livers of mice. CdSe QDs induced dose-dependent cell death in hepatocytes with an IC50 = 20.4 μM. Pre-treatment with SFN (5 μM increased cell viability in response to CdSe QDs (20 μM from 49.5 to 89.3%. SFN induced a pro-oxidant effect characterized by depletion of intracellular reduced glutathione during short term exposure (3-6 h, followed by up-regulation of antioxidant enzymes and glutathione levels at 24 h. SFN also caused Nrf2 translocation into the nucleus, up-regulation of antioxidant enzymes and autophagy. siRNA knockdown of Nrf2 suggests that the Nrf2 pathway plays a role in the protection against CdSe QD-induced cell death. Wortmannin inhibition of SFN-induced autophagy significantly suppressed the protective effect of SFN on CdSe QD-induced cell death. Moreover, the role of autophagy in SFN protection against CdSe QD-induced cell death was confirmed using mouse embryonic fibroblasts lacking ATG5. CdSe QDs caused significant liver damage in mice, and this was decreased by SFN treatment. In conclusion, SFN attenuated the cytotoxicity of CdSe QDs in both human hepatocytes and in the mouse liver, and this protection was associated with the induction of Nrf2 pathway and autophagy.

Cutting Edge: Eosinophils Undergo Caspase-1-Mediated Pyroptosis in Response to Necrotic Liver Cells.

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Palacios-Macapagal, Daphne; Connor, Jane; Mustelin, Tomas; Ramalingam, Thirumalai R; Wynn, Thomas A; Davidson, Todd S

2017-08-01

Many chronic liver disorders are characterized by dysregulated immune responses and hepatocyte death. We used an in vivo model to study the immune response to necrotic liver injury and found that necrotic liver cells induced eosinophil recruitment. Necrotic liver induced eosinophil IL-1β and IL-18 secretion, degranulation, and cell death. Caspase-1 inhibitors blocked all of these responses. Caspase-1-mediated cell death with accompanying cytokine release is the hallmark of a novel form of cell death termed pyroptosis. To confirm this response in a disease model, we isolated eosinophils from the livers of Schistosoma mansoni -infected mice. S. mansoni eggs lodge in the hepatic sinusoids of infected mice, resulting in hepatocyte death, inflammation, and progressive liver fibrosis. This response is typified by massive eosinophilia, and we were able to confirm pyroptosis in the infiltrating eosinophils. This demonstrated that pyroptosis is a cellular pathway used by eosinophils in response to large-scale hepatic cell death. Copyright © 2017 by The American Association of Immunologists, Inc.

Liver cell-derived microparticles activate hedgehog signaling and alter gene expression in hepatic endothelial cells.

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Witek, Rafal P; Yang, Liu; Liu, Renshui; Jung, Youngmi; Omenetti, Alessia; Syn, Wing-Kin; Choi, Steve S; Cheong, Yeiwon; Fearing, Caitlin M; Agboola, Kolade M; Chen, Wei; Diehl, Anna Mae

2009-01-01

Angiogenesis contributes to vascular remodeling during cirrhosis. In cirrhotic livers, cholangiocytes, and myofibroblastic hepatic stellate cells (MF-HSC) produce Hedgehog (Hh) ligands. During embryogenesis Hh ligands are released from ligand-producing cells in microparticles and activate Hh signaling in endothelial cells. We studied whether adult liver cell-derived microparticles contain Hh ligands that alter hepatic sinusoidal endothelial cells (SEC). MF-HSC and cholangiocytes were exposed to platelet-derived growth factor to induce Hh ligands; microparticles were isolated from medium, analyzed by transmission electron microscopy and immunoblots, and applied to Hh-reporter-containing cells. Microparticles were obtained from serum and bile of rats after bile duct ligation (BDL) or sham surgery and applied to normal primary liver SEC with or without cyclopamine, an Hh signaling inhibitor. Effects on SEC gene expression were evaluated by quantitative reverse-transcription polymerase chain reaction and immunoblotting. Hh target gene expression and SEC activation markers were compared in primary SEC and in liver sections from healthy and BDL rats. Platelet-derived growth factor-treated MF-HSC and cholangiocytes released exosome-enriched microparticles containing biologically-active Hh ligands. BDL increased release of Hh-containing exosome-enriched microparticles into plasma and bile. Transmission electron microscopy and immunoblots revealed similarities among microparticles from all sources; all microparticles induced similar Hh-dependent changes in SEC gene expression. SEC from healthy livers did not express Hh target genes or activation markers, but both were up-regulated in SEC after BDL. Hh-containing exosome-enriched microparticles released from liver cells alter hepatic SEC gene expression, suggesting a novel mechanism for cirrhotic vasculopathy.

Liver Cell Culture Devices

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Andria, B.; Bracco, A.; Cirino, G.; Chamuleau, R. A. F. M.

2010-01-01

In the last 15 years many different liver cell culture devices, consisting of functional liver cells and artificial materials, have been developed. They have been devised for numerous different applications, such as temporary organ replacement (a bridge to liver transplantation or native liver

Pro-inflammatory activated Kupffer cells by lipids induce hepatic NKT cells deficiency through activation-induced cell death.

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Tongfang Tang

Full Text Available BACKGROUND: Dietary lipids play an important role in the progression of non-alcoholic fatty liver disease (NAFLD through alternation of liver innate immune response. AIMS: The present study was to investigate the effect of lipid on Kupffer cells phenotype and function in vivo and in vitro. And further to investigate the impact of lipid on ability of Kupffer cell lipid antigen presentation to activate NKT cells. METHODS: Wild type male C57BL/6 mice were fed either normal or high-fat diet. Hepatic steatosis, Kupffer cell abundance, NKT cell number and cytokine gene expression were evaluated. Antigen presentation assay was performed with Kupffer cells treated with certain fatty acids in vitro and co-cultured with NKT cells. RESULTS: High-fat diet induced hepatosteatosis, significantly increased Kupffer cells and decreased hepatic NKT cells. Lipid treatment in vivo or in vitro induced increase of pro-inflammatory cytokines gene expression and toll-like receptor 4 (TLR4 expression in Kupffer cells. Kupffer cells expressed high levels of CD1d on cell surface and only presented exogenous lipid antigen to activate NKT cells. Ability of Kupffer cells to present antigen and activate NKT cells was enhanced after lipid treatment. In addition, pro-inflammatory activated Kupffer cells by lipid treatment induced hepatic NKT cells activation-induced apoptosis and necrosis. CONCLUSION: High-fat diet increase Kupffer cells number and induce their pro-inflammatory status. Pro-inflammatory activated Kupfffer cells by lipid promote hepatic NKT cell over-activation and cell death, which lead to further hepatic NKT cell deficiency in the development of NAFLD.

Pro-inflammatory activated Kupffer cells by lipids induce hepatic NKT cells deficiency through activation-induced cell death.

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Tang, Tongfang; Sui, Yongheng; Lian, Min; Li, Zhiping; Hua, Jing

2013-01-01

Dietary lipids play an important role in the progression of non-alcoholic fatty liver disease (NAFLD) through alternation of liver innate immune response. The present study was to investigate the effect of lipid on Kupffer cells phenotype and function in vivo and in vitro. And further to investigate the impact of lipid on ability of Kupffer cell lipid antigen presentation to activate NKT cells. Wild type male C57BL/6 mice were fed either normal or high-fat diet. Hepatic steatosis, Kupffer cell abundance, NKT cell number and cytokine gene expression were evaluated. Antigen presentation assay was performed with Kupffer cells treated with certain fatty acids in vitro and co-cultured with NKT cells. High-fat diet induced hepatosteatosis, significantly increased Kupffer cells and decreased hepatic NKT cells. Lipid treatment in vivo or in vitro induced increase of pro-inflammatory cytokines gene expression and toll-like receptor 4 (TLR4) expression in Kupffer cells. Kupffer cells expressed high levels of CD1d on cell surface and only presented exogenous lipid antigen to activate NKT cells. Ability of Kupffer cells to present antigen and activate NKT cells was enhanced after lipid treatment. In addition, pro-inflammatory activated Kupffer cells by lipid treatment induced hepatic NKT cells activation-induced apoptosis and necrosis. High-fat diet increase Kupffer cells number and induce their pro-inflammatory status. Pro-inflammatory activated Kupfffer cells by lipid promote hepatic NKT cell over-activation and cell death, which lead to further hepatic NKT cell deficiency in the development of NAFLD.

Arsenic induces apoptosis in mouse liver is mitochondria dependent and is abrogated by N-acetylcysteine

International Nuclear Information System (INIS)

Santra, Amal; Chowdhury, Abhijit; Ghatak, Subhadip; Biswas, Ayan; Dhali, Gopal Krishna

2007-01-01

Arsenicosis, caused by arsenic contamination of drinking water supplies, is a major public health problem in India and Bangladesh. Chronic liver disease, often with portal hypertension occurs in chronic arsenicosis, contributes to the morbidity and mortality. The early cellular events that initiate liver cell injury due to arsenicosis have not been studied. Our aim was to identify the possible mechanisms related to arsenic-induced liver injury in mice. Liver injury was induced in mice by arsenic treatment. The liver was used for mitochondrial oxidative stress, mitochondrial permeability transition (MPT). Evidence of apoptosis was sought by TUNEL test, caspase assay and histology. Pretreatment with N-acetyl-L-cysteine (NAC) was done to modulate hepatic GSH level. Arsenic treatment in mice caused liver injury associated with increased oxidative stress in liver mitochondria and alteration of MPT. Altered MPT facilitated cytochrome c release in the cytosol, activation of caspase 9 and caspase 3 activities and apoptotic cell death. Pretreatment of NAC to arsenic-treated mice abrogated all these alteration suggesting a glutathione (GSH)-dependent mechanism. Oxidative stress in mitochondria and inappropriate MPT are important in the pathogenesis of arsenic induced apoptotic liver cell injury. The phenomenon is GSH dependent and supplementation of NAC might have beneficial effects

A long-term three dimensional liver co-culture system for improved prediction of clinically relevant drug-induced hepatotoxicity

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Kostadinova, Radina; Boess, Franziska; Applegate, Dawn; Suter, Laura; Weiser, Thomas; Singer, Thomas; Naughton, Brian; Roth, Adrian

2013-01-01

Drug-induced liver injury (DILI) is the major cause for liver failure and post-marketing drug withdrawals. Due to species-specific differences in hepatocellular function, animal experiments to assess potential liabilities of drug candidates can predict hepatotoxicity in humans only to a certain extent. In addition to animal experimentation, primary hepatocytes from rat or human are widely used for pre-clinical safety assessment. However, as many toxic responses in vivo are mediated by a complex interplay among different cell types and often require chronic drug exposures, the predictive performance of hepatocytes is very limited. Here, we established and characterized human and rat in vitro three-dimensional (3D) liver co-culture systems containing primary parenchymal and non-parenchymal hepatic cells. Our data demonstrate that cells cultured on a 3D scaffold have a preserved composition of hepatocytes, stellate, Kupffer and endothelial cells and maintain liver function for up to 3 months, as measured by the production of albumin, fibrinogen, transferrin and urea. Additionally, 3D liver co-cultures maintain cytochrome P450 inducibility, form bile canaliculi-like structures and respond to inflammatory stimuli. Upon incubation with selected hepatotoxicants including drugs which have been shown to induce idiosyncratic toxicity, we demonstrated that this model better detected in vivo drug-induced toxicity, including species-specific drug effects, when compared to monolayer hepatocyte cultures. In conclusion, our results underline the importance of more complex and long lasting in vitro cell culture models that contain all liver cell types and allow repeated drug-treatments for detection of in vivo-relevant adverse drug effects. - Highlights: ► 3D liver co-cultures maintain liver specific functions for up to three months. ► Activities of Cytochrome P450s remain drug- inducible accross three months. ► 3D liver co-cultures recapitulate drug-induced liver toxicity

A long-term three dimensional liver co-culture system for improved prediction of clinically relevant drug-induced hepatotoxicity

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Kostadinova, Radina; Boess, Franziska [Non-Clinical Safety, Hoffmann-La Roche Ltd, Grenzacherstrasse 124, Building 73 / Room 117b, 4070 Basel (Switzerland); Applegate, Dawn [RegeneMed, 9855 Towne Centre Drive Suite 200, San Diego, CA 92121 (United States); Suter, Laura; Weiser, Thomas; Singer, Thomas [Non-Clinical Safety, Hoffmann-La Roche Ltd, Grenzacherstrasse 124, Building 73 / Room 117b, 4070 Basel (Switzerland); Naughton, Brian [RegeneMed, 9855 Towne Centre Drive Suite 200, San Diego, CA 92121 (United States); Roth, Adrian, E-mail: adrian_b.roth@roche.com [Non-Clinical Safety, Hoffmann-La Roche Ltd, Grenzacherstrasse 124, Building 73 / Room 117b, 4070 Basel (Switzerland)

2013-04-01

Drug-induced liver injury (DILI) is the major cause for liver failure and post-marketing drug withdrawals. Due to species-specific differences in hepatocellular function, animal experiments to assess potential liabilities of drug candidates can predict hepatotoxicity in humans only to a certain extent. In addition to animal experimentation, primary hepatocytes from rat or human are widely used for pre-clinical safety assessment. However, as many toxic responses in vivo are mediated by a complex interplay among different cell types and often require chronic drug exposures, the predictive performance of hepatocytes is very limited. Here, we established and characterized human and rat in vitro three-dimensional (3D) liver co-culture systems containing primary parenchymal and non-parenchymal hepatic cells. Our data demonstrate that cells cultured on a 3D scaffold have a preserved composition of hepatocytes, stellate, Kupffer and endothelial cells and maintain liver function for up to 3 months, as measured by the production of albumin, fibrinogen, transferrin and urea. Additionally, 3D liver co-cultures maintain cytochrome P450 inducibility, form bile canaliculi-like structures and respond to inflammatory stimuli. Upon incubation with selected hepatotoxicants including drugs which have been shown to induce idiosyncratic toxicity, we demonstrated that this model better detected in vivo drug-induced toxicity, including species-specific drug effects, when compared to monolayer hepatocyte cultures. In conclusion, our results underline the importance of more complex and long lasting in vitro cell culture models that contain all liver cell types and allow repeated drug-treatments for detection of in vivo-relevant adverse drug effects. - Highlights: ► 3D liver co-cultures maintain liver specific functions for up to three months. ► Activities of Cytochrome P450s remain drug- inducible accross three months. ► 3D liver co-cultures recapitulate drug-induced liver toxicity

Reduced cadmium-induced cytotoxicity in cultured liver cells following 5-azacytidine pretreatment

International Nuclear Information System (INIS)

Waalkes, M.P.; Wilson, M.J.; Poirier, L.A.

1985-01-01

Recent work indicated that administration of the pyrimidine analog 5-azacytidine (AZA), either to cells in culture or to rats, results in an enhancement of expression of the metallothionein (MT) gene. Since MT is thought to play a central role in the detoxification of cadmium, the present study was designed to assess the effect of AZA pretreatment on cadmium cytotoxicity. Cultured rat liver cells in log phase of growth were first exposed to AZA (8 microM). Forty-eight hours later, cadmium was added. A modest increase in MT amounts over control was detected after AZA treatment alone. Cadmium alone resulted in a 10-fold increase in MT concentrations. The combination of AZA pretreatment followed by cadmium exposure caused a 23-fold increase in MT concentrations over control. Treatment with the DNA synthesis inhibitor hydroxyurea (HU) eliminated the enhancing effect of AZA pretreatment on cadmium induction of MT, indicating that cell division is required. AZA-pretreated cells were also harvested and incubated in suspension with cadmium for 0 to 90 min. AZA-pretreated cells showed marked reductions in cadmium-induced cytotoxicity as reflected by reduced intracellular potassium loss, glutamic-oxaloacetic transaminase loss, and lipid peroxidation following cadmium exposure. Results suggest that AZA pretreatment induces tolerance to cadmium cytotoxicity which appears to be due to an increased capacity to synthesize MT rather than high quantities of preexisting MT at the time of cadmium exposure

Necrostatin-1 protects against reactive oxygen species (ROS-induced hepatotoxicity in acetaminophen-induced acute liver failure

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Kenji Takemoto

2014-01-01

Full Text Available Excessive acetaminophen (APAP use is one of the most common causes of acute liver failure. Various types of cell death in the damaged liver are linked to APAP-induced hepatotoxicity, and, of these, necrotic cell death of hepatocytes has been shown to be involved in disease pathogenesis. Until recently, necrosis was commonly considered to be a random and unregulated form of cell death; however, recent studies have identified a previously unknown form of programmed necrosis called receptor-interacting protein kinase (RIPK-dependent necrosis (or necroptosis, which is controlled by the kinases RIPK1 and RIPK3. Although RIPK-dependent necrosis has been implicated in a variety of disease states, including atherosclerosis, myocardial organ damage, stroke, ischemia–reperfusion injury, pancreatitis, and inflammatory bowel disease. However its involvement in APAP-induced hepatocyte necrosis remains elusive. Here, we showed that RIPK1 phosphorylation, which is a hallmark of RIPK-dependent necrosis, was induced by APAP, and the expression pattern of RIPK1 and RIPK3 in the liver overlapped with that of CYP2E1, whose activity around the central vein area has been demonstrated to be critical for the development of APAP-induced hepatic injury. Moreover, a RIPK1 inhibitor ameliorated APAP-induced hepatotoxicity in an animal model, which was underscored by significant suppression of the release of hepatic enzymes and cytokine expression levels. RIPK1 inhibition decreased reactive oxygen species levels produced in APAP-injured hepatocytes, whereas CYP2E1 expression and the depletion rate of total glutathione were unaffected. Of note, RIPK1 inhibition also conferred resistance to oxidative stress in hepatocytes. These data collectively demonstrated a RIPK-dependent necrotic mechanism operates in the APAP-injured liver and inhibition of this pathway may be beneficial for APAP-induced fulminant hepatic failure.

Differential contribution of complement receptor C5aR in myeloid and non-myeloid cells in chronic ethanol-induced liver injury in mice.

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McCullough, Rebecca L; McMullen, Megan R; Das, Dola; Roychowdhury, Sanjoy; Strainic, Michael G; Medof, M Edward; Nagy, Laura E

2016-07-01

Complement is implicated in the development of alcoholic liver disease. C3 and C5 contribute to ethanol-induced liver injury; however, the role of C5a receptor (C5aR) on myeloid and non-myeloid cells to progression of injury is not known. C57BL/6 (WT), global C5aR-/-, myeloid-specific C5aR-/-, and non-myeloid-specific C5aR-/- mice were fed a Lieber-DeCarli diet (32%kcal EtOH) for 25 days. Cultured hepatocytes were challenged with ethanol, TNFα, and C5a. Chronic ethanol feeding increased expression of pro-inflammatory mediators in livers of WT mice; this response was completely blunted in C5aR-/- mice. However, C5aR-/- mice were not protected from other measures of hepatocellular damage, including ethanol-induced increases in hepatic triglycerides, plasma alanine aminotransferase and hepatocyte apoptosis. CYP2E1 and 4-hydroxynonenal protein adducts were induced in WT and C5aR-/- mice. Myeloid-specific C5aR-/- mice were protected from ethanol-induced increases in hepatic TNFα, whereas non-myeloid-specific C5aR-/- displayed increased hepatocyte apoptosis and inflammation after chronic ethanol feeding. In cultured hepatocytes, cytotoxicity induced by challenge with ethanol and TNFα was completely eliminated by treatment with C5a in cells from WT, but not C5aR-/- mice. Further, treatment with C5a enhanced activation of pro-survival signal AKT in hepatocytes challenged with ethanol and TNFα. Taken together, these data reveal a differential role for C5aR during ethanol-induced liver inflammation and injury, with C5aR on myeloid cells contributing to ethanol-induced inflammatory cytokine expression, while non-myeloid C5aR protects hepatocytes from death after chronic ethanol feeding. Copyright © 2016 Elsevier Ltd. All rights reserved.

Treatment with 4-methylpyrazole modulated stellate cells and natural killer cells and ameliorated liver fibrosis in mice.

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Hyon-Seung Yi

Full Text Available Accumulating evidence suggests that retinol and its metabolites are closely associated with liver fibrogenesis. Recently, we demonstrated that genetic ablation of alcohol dehydrogenase 3 (ADH3, a retinol metabolizing gene that is expressed in hepatic stellate cells (HSCs and natural killer (NK cells, attenuated liver fibrosis in mice. In the current study, we investigated whether pharmacological ablation of ADH3 has therapeutic effects on experimentally induced liver fibrosis in mice.Liver fibrosis was induced by intraperitoneal injections of carbon tetrachloride (CCl4 or bile duct ligation (BDL for two weeks. To inhibit ADH3-mediated retinol metabolism, 10 μg 4-methylpyrazole (4-MP/g of body weight was administered to mice treated with CCl4 or subjected to BDL. The mice were sacrificed at week 2 to evaluate the regression of liver fibrosis. Liver sections were stained for collagen and α-smooth muscle actin (α-SMA. In addition, HSCs and NK cells were isolated from control and treated mice livers for molecular and immunological studies.Treatment with 4-MP attenuated CCl4- and BDL-induced liver fibrosis in mice, without any adverse effects. HSCs from 4-MP treated mice depicted decreased levels of retinoic acids and increased retinol content than HSCs from control mice. In addition, the expression of α-SMA, transforming growth factor-β1 (TGF-β1, and type I collagen α1 was significantly reduced in the HSCs of 4-MP treated mice compared to the HSCs from control mice. Furthermore, inhibition of retinol metabolism by 4-MP increased interferon-γ production in NK cells, resulting in increased apoptosis of activated HSCs.Based on our data, we conclude that inhibition of retinol metabolism by 4-MP ameliorates liver fibrosis in mice through activation of NK cells and suppression of HSCs. Therefore, retinol and its metabolizing enzyme, ADH3, might be potential targets for therapeutic intervention of liver fibrosis.

Radioprotective role of H2S/CSE pathway in Chang liver cells

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Pan Yan; Ye Shuang; Yuan Dexiao; Zhang Jianghong; Bai Yang; Shao Chunlin

2012-01-01

Radiation-induced liver cell damage may be life-threatening. Here, we investigated whether hydrogen sulfide (H 2 S)/cystathionine γ-lyase (CSE) pathway could serve the protective role toward radiation in normal human liver cells. Our data showed that pretreatment of cells with H 2 S donor, sodium hydrosulfide (NaHS) significantly attenuated radiation induced micronuclei formation and improved cell viability. However, the use of DL-propargylglycine (PPG), a potent inhibitor of CSE, markedly enhanced the cell-killing effect induced by radiation. Exposure of cells to 2 Gy γ-radiation led to significant increases of the endogenous H 2 S content. The mRNA and protein expressions of CSE also increased after radiation in a time-dependent manner, while the expression of cystathionine β-synthase (CBS), another endogenous H 2 S synthetase, did not change significantly. Notably, radiation induced production of reactive oxygen species (ROS) was significantly reversed by the pretreatment of NaHS, while blockage of CSE activity resulted in an enhanced ROS production in irradiated cells. Moreover, NaHS markedly suppressed radiation-induced phosphorylation of P53, decrease of Bcl-2/Bax, and activity of nuclear factor kappaB (NF-κB). In conclusion, our finding demonstrates that H 2 S/CSE pathway plays a radioprotection role by inhibiting radiation-induced ROS production, P53 phosphorylation, NF-κB activation and decrease of Bcl-2/Bax, indicating that modulation of H 2 S may be a novel protection strategy for liver radiation injury in radiotherapy.

Hepatocyte growth factor gene-modified adipose-derived mesenchymal stem cells ameliorate radiation induced liver damage in a rat model.

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Jiamin Zhang

Full Text Available Liver damage caused by radiotherapy is associated with a high mortality rate, but no established treatment exists. Adipose-derived mesenchymal stem cells (ADSCs are capable of migration to injured tissue sites, where they aid in the repair of the damage. Hepatocyte growth factor (HGF is critical for damage repair due to its anti-apoptotic, anti-fibrotic and cell regeneration-promoting effects. This study was performed to investigate the therapeutic effects of HGF-overexpressing ADSCs on radiation-induced liver damage (RILD. ADSCs were infected with a lentivirus encoding HGF and HGF-shRNA. Sprague-Dawley (SD rats received 60Gy of irradiation to induce liver injury and were immediately given either saline, ADSCs, ADSCs + HGF or ADSCs + shHGF. Two days after irradiation, a significant reduction in apoptosis was observed in the HGF-overexpressing ADSC group compared with the RILD group, as assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL staining. Scanning electron microscopy showed chromatin condensation after irradiation, which was ameliorated in the group that received ADSCs and was reversed in the group that received HGF-overexpressing ADSCs. HGF-overexpressing ADSCs ameliorated radiation- induced liver fibrosis through down regulation of α-SMA and fibronectin. Hepatocyte regeneration was significantly improved in rats treated with ADSCs compared with rats from the RILD group, as assessed by Ki-67 immunohistochemistry. Rats that received HGF-overexpressing ADSCs showed an even greater level of hepatocyte regeneration. HGF-overexpressing ADSCs completely blocked the radiation-induced increase in the enzymes ALT and AST. The effect of mitigating RILD was compromised in the ADSC + shHGF group compared with the ADSC group. Altogether, these results suggest that HGF-overexpressing ADSCs can significantly improve RILD in a rat model, which may serve as a valuable therapeutic alternative.

NK Cell Subtypes as Regulators of Autoimmune Liver Disease

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Guohui Jiao

2016-01-01

Full Text Available As major components of innate immunity, NK cells not only exert cell-mediated cytotoxicity to destroy tumors or infected cells, but also act to regulate the functions of other cells in the immune system by secreting cytokines and chemokines. Thus, NK cells provide surveillance in the early defense against viruses, intracellular bacteria, and cancer cells. However, the effecter function of NK cells must be exquisitely controlled to prevent inadvertent attack against normal “self” cells. In an organ such as the liver, where the distinction between immunotolerance and immune defense against routinely processed pathogens is critical, the plethora of NK cells has a unique role in the maintenance of homeostasis. Once self-tolerance is broken, autoimmune liver disease resulted. NK cells act as a “two-edged weapon” and even play opposite roles with both regulatory and inducer activities in the hepatic environment. That is, NK cells act not only to produce inflammatory cytokines and chemokines, but also to alter the proliferation and activation of associated lymphocytes. However, the precise regulatory mechanisms at work in autoimmune liver diseases remain to be identified. In this review, we focus on recent research with NK cells and their potential role in the development of autoimmune liver disease.

Zerumbone induced apoptosis in liver cancer cells via modulation of Bax/Bcl-2 ratio

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Azimahtol Hawariah LP

2007-04-01

Full Text Available Abstract Background Zerumbone is a cytotoxic component isolated from Zingiber zerumbet Smith, a herbal plant which is also known as lempoyang. This new anticancer bioactive compound from Z. zerumbet was investigated for its activity and mechanism in human liver cancer cell lines. Results Zerumbone significantly showed an antiproliferative activity upon HepG2 cells with an IC50 of 3.45 ± 0.026 μg/ml. Zerumbone was also found to inhibit the proliferation of non-malignant Chang Liver and MDBK cell lines. However the IC50 obtained was higher compared to the IC50 for HepG2 cells (> 10 μg/ml. The extent of DNA fragmentation was evaluated by the Tdt-mediated dUTP nick end labelling assay which showed that, zerumbone significantly increased apoptosis in HepG2 cells in a time-course manner. In detail, the apoptotic process triggered by zerumbone involved the up-regulation of pro-apoptotic Bax protein and the suppression of anti-apoptotic Bcl-2 protein expression. The changes that occurred in the levels of this antagonistic proteins Bax/Bcl-2, was independent of p53 since zerumbone did not affect the levels of p53 although this protein exists in a functional form. Western blotting analysis for Bax protein was further confirmed qualitatively with an immunoassay that showed the distribution of Bax protein in zerumbone-treated cells. Conclusion Therefore, zerumbone was found to induce the apoptotic process in HepG2 cells through the up and down regulation of Bax/Bcl-2 protein independently of functional p53 activity.

Potential genotoxic and cytotoxicity of emamectin benzoate in human normal liver cells.

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Zhang, Zhijie; Zhao, Xinyu; Qin, Xiaosong

2017-10-10

Pesticide residue inducing cancer-related health problems draw people more attention recently. Emamectin benzoate (EMB) has been widely used in agriculture around the world based on its specificity targets. Although potential risk and the molecular mechanism of EMB toxicity to human liver has not been well-characterized. Unlike well-reported toxicity upon central nervous system, potential genotoxic and cytotoxicity of EMB in human liver cell was ignored and very limited. In this study, we identify genotoxicity and cytotoxicity of EMB to human normal liver cells (QSG7701 cell line) in vitro . We demonstrate that EMB inhibited the viability of QSG7701 cells and induced the DNA damage. Established assays of cytotoxicity were performed to characterize the mechanism of EMB toxicity on QSG7701 cells. Typical chromatin condensation and DNA fragmentation indicated the apoptosis of QSG7701 cells induced by EMB. And the intracellular biochemical results demonstrated that EMB-enhanced apoptosis of QSG7701 cells concurrent with generated ROS, a loss of mitochondrial membrane potential, the cytochrome-c release, up regulate the Bax/Bcl-2 and the activation of caspase-9/-3. Our results of EMB induces the death of QSG7701 cells maybe via mitochondrial-mediated intrinsic apoptotic pathways would contribute to promote the awareness of EMB as an extensive used pesticide to human being effects and reveal the underlying mechanisms of potential genotoxic.

Autophagy and gap junctional intercellular communication inhibition are involved in cadmium-induced apoptosis in rat liver cells

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Zou, Hui [College of Veterinary Medicine, Yangzhou University, and Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009 (China); Zhuo, Liling [College of Life Science, Zaozhuang University, Zaozhuang, Shandong, 277160 (China); Han, Tao; Hu, Di; Yang, Xiaokang; Wang, Yi; Yuan, Yan; Gu, Jianhong; Bian, Jianchun; Liu, Xuezhong [College of Veterinary Medicine, Yangzhou University, and Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009 (China); Liu, Zongping, E-mail: liuzongping@yzu.edu.cn [College of Veterinary Medicine, Yangzhou University, and Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009 (China)

2015-04-17

Cadmium (Cd) is known to induce hepatotoxicity, yet the underlying mechanism of how this occurs is not fully understood. In this study, Cd-induced apoptosis was demonstrated in rat liver cells (BRL 3A) with apoptotic nuclear morphological changes and a decrease in cell index (CI) in a time- and concentration-dependent manner. The role of gap junctional intercellular communication (GJIC) and autophagy in Cd-induced apoptosis was investigated. Cd significantly induced GJIC inhibition as well as downregulation of connexin 43 (Cx43). The prototypical gap junction blocker carbenoxolone disodium (CBX) exacerbated the Cd-induced decrease in CI. Cd treatment was also found to cause autophagy, with an increase in mRNA expression of autophagy-related genes Atg-5, Atg-7, Beclin-1, and microtubule-associated protein light chain 3 (LC3) conversion from cytosolic LC3-I to membrane-bound LC3-II. The autophagic inducer rapamycin (RAP) prevented the Cd-induced CI decrease, while the autophagic inhibitor chloroquine (CQ) caused a further reduction in CI. In addition, CBX promoted Cd-induced autophagy, as well as changes in expression of Atg-5, Atg-7, Beclin-1 and LC3. CQ was found to block the Cd-induced decrease in Cx43 and GJIC inhibition, whereas RAP had opposite effect. These results demonstrate that autophagy plays a protective role during Cd-induced apoptosis in BRL 3A cells during 6 h of experiment, while autophagy exacerbates Cd-induced GJIC inhibition which has a negative effect on cellular fate. - Highlights: • GJIC and autophagy is crucial for biological processes. • Cd exposure causes GJIC inhibition and autophagy increase in BRL 3A cells. • Autophagy protects Cd induced BRL 3A cells apoptosis at an early stage. • Autophagy exacerbates Cd-induced GJIC inhibition. • GJIC plays an important role in autophagy induced cell death or survival.

Antcin C from Antrodia cinnamomea Protects Liver Cells Against Free Radical-Induced Oxidative Stress and Apoptosis In Vitro and In Vivo through Nrf2-Dependent Mechanism

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M. Gokila Vani

2013-01-01

Full Text Available In this study, we investigated the cytoprotective effects of antcin C, a steroid-like compound isolated from Antrodia cinnamaomea against AAPH-induced oxidative stress and apoptosis in human hepatic HepG2 cells. Pretreatment with antcin C significantly protects hepatic cells from AAPH-induced cell death through the inhibition of ROS generation. Furthermore, AAPH-induced lipid peroxidation, ALT/AST secretion and GSH depletion was significantly inhibited by antcin C. The antioxidant potential of antcin C was correlated with induction of antioxidant genes including, HO-1, NQO-1, γ-GCLC, and SOD via transcriptional activation of Nrf2. The Nrf2 activation by antcin C is mediated by JNK1/2 and PI3K activation, whereas pharmacologic inhibition of JNK1/2 and PI3K abolished antcin C-induced Nrf2 activity. In addition, AAPH-induced apoptosis was significantly inhibited by antcin C through the down-regulation of pro-apoptotic factors including, Bax, cytochrome c, capase 9, -4, -12, -3, and PARP. In vivo studies also show that antcin C significantly protected mice liver from AAPH-induced hepatic injury as evidenced by reduction in hepatic enzymes in circulation. Further, immunocytochemistry analyses showed that antcin C significantly increased HO-1 and Nrf2 expression in mice liver tissues. These results strongly suggest that antcin C could protect liver cells from oxidative stress and cell death via Nrf2/ARE activation.

Hepatic overproduction of 13-HODE due to ALOX15 upregulation contributes to alcohol-induced liver injury in mice.

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Zhang, Wenliang; Zhong, Wei; Sun, Qian; Sun, Xinguo; Zhou, Zhanxiang

2017-08-21

Chronic alcohol feeding causes lipid accumulation and apoptosis in the liver. This study investigated the role of bioactive lipid metabolites in alcohol-induced liver damage and tested the potential of targeting arachidonate 15-lipoxygenase (ALOX15) in treating alcoholic liver disease (ALD). Results showed that chronic alcohol exposure induced hepatocyte apoptosis in association with increased hepatic 13-HODE. Exposure of 13-HODE to Hepa-1c1c7 cells induced oxidative stress, ER stress and apoptosis. 13-HODE also perturbed proteins related to lipid metabolism. HODE-generating ALOX15 was up-regulated by chronic alcohol exposure. Linoleic acid, but not ethanol or acetaldehyde, induced ALOX15 expression in Hepa-1c1c7 cells. ALOX15 knockout prevented alcohol-induced liver damage via attenuation of oxidative stress, ER stress, lipid metabolic disorder, and cell death signaling. ALOX15 inhibitor (PD146176) treatment also significantly alleviated alcohol-induced oxidative stress, lipid accumulation and liver damage. These results demonstrated that activation of ALOX15/13-HODE circuit critically mediates the pathogenesis of ALD. This study suggests that ALOX15 is a potential molecular target for treatment of ALD.

Disruption of contact inhibition in rat liver epithelial cells by various types of AhR ligands

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Vondracek, J.; Chramostova, K.; Kozubik, A. [Institute of Biophysics, Brno (Czech Republic); Krcmar, P.; Machala, M. [Veterinary Research Institute, Brno (Czech Republic)

2004-09-15

The maintenance of a balance between cell gain and cell loss is essential for proper liver function. The exact role of aryl hydrocarbon receptor (AhR) in regulating cell proliferation and apoptosis of liver cells remains unclear, since ligand-dependent activation of AhR has been shown to induce cell cycle arrest, proliferation, differentiation or apoptosis, depending on the cellular model used. AhR can directly interact with retinoblastoma protein in hepatic cells, forming protein complexes that can efficiently block cell cycle progression by inducing G1 arrest, or to induce the expression of inhibitors of cyclin-dependent kinases, such as p271. On the other hand, it has been suggested that AhR could play a stimulatory role in cell proliferation, either directly or by mediating a release from contact inhibition. It is now generally accepted that progenitor cells exist in the liver, are activated in various liver diseases and can form a potential target cell population for both tumor initiating and tumor promoting chemicals4. 2,3,7,8-tetrachlorodibenzo-pdioxin (TCDD) has been found to release rat liver epithelial cells from contact inhibition by upregulating cyclin A expression and cyclin A/cdk2 activity. Our previous studies have shown that a number of AhR ligands5,6 can stimulate proliferation of confluent of rat liver epithelial ''stem-like'' WB-F344 cells. Such mechanism could play a role in liver tumor promotion. In the present study, we used flavonoid compounds that have been reported to act either as pure agonists, such as beta-naphthoflavone (BNF), or as partial/complete antagonists of AhR - alpha-naphthoflavone (ANF) and 3'-methoxy-4'-nitroflavone (3'M4'NF), in order to investigate effects of AhR agonists/antagonists on confluent rat liver epithelial cells. The present study aimed to investigate the effects of model flavonoids on the release of rat liver epithelial cells from contact inhibition, and on inducibility of

Nickel oxide nanoparticles exert cytotoxicity via oxidative stress and induce apoptotic response in human liver cells (HepG2).

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Ahamed, Maqusood; Ali, Daoud; Alhadlaq, Hisham A; Akhtar, Mohd Javed

2013-11-01

Increasing use of nickel oxide nanoparticles (NiO NPs) necessitates an improved understanding of their potential impact on human health. Previously, toxic effects of NiO NPs have been investigated, mainly on airway cells. However, information on effect of NiO NPs on human liver cells is largely lacking. In this study, we investigated the reactive oxygen species (ROS) mediated cytotoxicity and induction of apoptotic response in human liver cells (HepG2) due to NiO NPs exposure. Prepared NiO NPs were crystalline and spherical shaped with an average diameter of 44 nm. NiO NPs induced cytotoxicity (cell death) and ROS generation in HepG2 cells in dose-dependent manner. Further, ROS scavenger vitamin C reduced cell death drastically caused by NiO NPs exposure indicating that oxidative stress plays an important role in NiO NPs toxicity. Micronuclei induction, chromatin condensation and DNA damage in HepG2 cells treated with NiO NPs suggest that NiO NPs induced cell death via apoptotic pathway. Quantitative real-time PCR analysis showed that following the exposure of HepG2 cells to NiO NPs, the expression level of mRNA of apoptotic genes (bax and caspase-3) were up-regulated whereas the expression level of anti-apoptotic gene bcl-2 was down-regulated. Moreover, activity of caspase-3 enzyme was also higher in NiO NPs treated cells. To the best of our knowledge this is the first report demonstrating that NiO NPs caused cytotoxicity via ROS and induced apoptosis in HepG2 cells, which is likely to be mediated through bax/bcl-2 pathway. This work warrants careful assessment of Ni NPs before their commercial and industrial applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

A new liver function test using the asialoglycoprotein-receptor system on the liver cell membrane, 3

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Hazama, Hiroshi; Kawa, Soukichi; Kubota, Yoshitsugu

1986-01-01

We evaluated the vilidity of a new liver function test using liver scintigraphy based on the asialoglycoprotein (ASGP) receptor system on the liver cell membrane in rats with galactosamine-induced acute liver disorder and those with carbon tetra-chloride-induced chronic liver disorder. Neoglycoprotein (GHSA) produced by combining human serum albumin with 32 galactose units was labeled with 99m Tc and administered (50 μg/100 g body weight) to rats with acute or chronic liver disorder. Clearance curves were produced based on liver scintigrams and analysed using the two-compartment model to obtain parameters. In acute liver disorder, the prolongation of 99m Tc-GHSA clearance and the decrease in ASGP receptor activities correlated well to the increase in serum GOT and the decrease in the esterified to total cholesterol ratio (E/T ratio); in chronic liver disorder, they correlated significantly to the increase in the content of liver hydroxyproline (Hyp) which increased in proportion to the severity of liver fibrosis studied histologically, and to the decrease in the contents of cytochrome P-450 and cytochrome b 5 in liver microsomes. Significant correlation was observed between the prolongation of 99m Tc-GHSA clearance and the decrease in ASGP receptor activities in both acute and chronic liver disorders. These findings indicate that the measurement of 99m Tc-GHSA clearance can be a new liver function test sensitively reflecting the severity of liver damage. (author)

Hepatocyte transplantation and advancements in alternative cell sources for liver-based regenerative medicine.

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Lee, Charlotte A; Sinha, Siddharth; Fitzpatrick, Emer; Dhawan, Anil

2018-06-01

Human hepatocyte transplantation has been actively perused as an alternative to liver replacement for acute liver failure and liver-based metabolic defects. Current challenges in this field include a limited cell source, reduced cell viability following cryopreservation and poor engraftment of cells into the recipient liver with consequent limited life span. As a result, alternative stem cell sources such as pluripotent stem cells, fibroblasts, hepatic progenitor cells, amniotic epithelial cells and mesenchymal stem/stromal cells (MSCs) can be used to generate induced hepatocyte like cells (HLC) with each technique exhibiting advantages and disadvantages. HLCs may have comparable function to primary human hepatocytes and could offer patient-specific treatment. However, long-term functionality of transplanted HLCs and the potential oncogenic risks of using stem cells have yet to be established. The immunomodulatory effects of MSCs are promising, and multiple clinical trials are investigating their effect in cirrhosis and acute liver failure. Here, we review the current status of hepatocyte transplantation, alternative cell sources to primary human hepatocytes and their potential in liver regeneration. We also describe recent clinical trials using hepatocytes derived from stem cells and their role in improving the phenotype of several liver diseases.

Hepatoprotective Effect of Trigona spp. Bee Propolis against Carbon Tetrachloride-Induced Liver Injury in Rat

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Rachel Amelia

2016-06-01

Full Text Available Background: Oxidative stress reaction can cause liver injury. This process can be prevented by antioxidant activities which can break the destructive chain caused by free radical substances in the liver. Propolis produced by Trigona spp. bee is known to have a high level of antioxidant. The aim of this study was to examine the effect of Trigona spp. bee propolis on liver histological toxicity caused by carbon tetrachloride-induced oxidative stress. Methods:This experimental study was conducted in September 2013 at the Animal Laboratory of Departement of Pharmacology and Therapy, Faculty of Medicine Universitas Padjadjaran. Twenty-four healthy male Wistar rats as objects were adapted for one week and randomly divided into 3 groups. Group I was the control negative, group II was given carbon tetrachloride on day 14, group III was given Trigona spp. bee propolis on day 1-14. On day 14, group III was injected CCl4 intraperitoneally. The quantitative data were statistically analyzed using the one way ANOVA and Tukey test with p value < 0.05. Results: Group I showed the liver contained normal cells, without significant injury of the membrane, round and complete nucleus. The average number of liver cell was 464 ± 9.59281 cells/field; group II underwent necrosis and the average of the cells was 146 ± 7.56885 cells/field; group III showed some normal liver cells, and some necrotic area with the normal liver cells average was 263 ± 14.10860 cells/field. The p-value=0.00. Conclusions: Trigona spp. bee propolis has a hepatoprotective effect against CCl4-induced liver injury histologically.

PTP1B confers liver fibrosis by regulating the activation of hepatic stellate cells

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Chen, Pei-Jie; Cai, Shuang-Peng; Yang, Yang; Li, Wan-Xia; Huang, Cheng; Meng, Xiao-Ming; Li, Jun, E-mail: lj@ahmu.edu.cn

2016-02-01

Liver fibrosis is a reversible wound-healing response to chronic hepatic injuries. Activation of hepatic stellate cells (HSCs) plays a pivotal role in the development of hepatic fibrosis. The currently accepted mechanism for the resolution of liver fibrosis is the apoptosis and inactivation of activated HSCs. Protein tyrosine phosphatase 1B (PTP1B), a prototype of non-receptor protein tyrosine phosphatase, is proved to be a vital modulator in cardiac fibrogenesis. However, the precise role of PTP1B on liver fibrosis and HSC activation is still unclear. Our study showed that the expression of PTP1B was elevated in fibrotic liver but reduced after spontaneous recovery. Moreover, stimulation of HSC-T6 cells with transforming growth factor-β1 (TGF-β1) resulted in a dose/time-dependent increase of PTP1B mRNA and protein. Co-incubation of HSC-T6 cells with PTP1B-siRNA inhibited the cell proliferation and activation induced by TGF-β1. Additionally, both mRNA and protein of PTP1B were dramatically decreased in inactivated HSCs after treated with adipogenic differentiation mixture (MDI). Over-expression of PTP1B hindered the inactivation of HSC-T6 cells induced by MDI. These observations revealed a regulatory role of PTP1B in liver fibrosis and implied PTP1B as a potential therapeutic target. - Highlights: • The expression of PTP1B in the fibrotic livers and recovery livers • The expression of PTP1B in activated and inactivated HSCs • Blockade of PTP1B inhibited the TGF-β1-induced proliferation and activation of HSCs. • Over-expression of PTP1B abolished the inactivation of HSCs induced by MDI.

PTP1B confers liver fibrosis by regulating the activation of hepatic stellate cells

International Nuclear Information System (INIS)

Chen, Pei-Jie; Cai, Shuang-Peng; Yang, Yang; Li, Wan-Xia; Huang, Cheng; Meng, Xiao-Ming; Li, Jun

2016-01-01

Liver fibrosis is a reversible wound-healing response to chronic hepatic injuries. Activation of hepatic stellate cells (HSCs) plays a pivotal role in the development of hepatic fibrosis. The currently accepted mechanism for the resolution of liver fibrosis is the apoptosis and inactivation of activated HSCs. Protein tyrosine phosphatase 1B (PTP1B), a prototype of non-receptor protein tyrosine phosphatase, is proved to be a vital modulator in cardiac fibrogenesis. However, the precise role of PTP1B on liver fibrosis and HSC activation is still unclear. Our study showed that the expression of PTP1B was elevated in fibrotic liver but reduced after spontaneous recovery. Moreover, stimulation of HSC-T6 cells with transforming growth factor-β1 (TGF-β1) resulted in a dose/time-dependent increase of PTP1B mRNA and protein. Co-incubation of HSC-T6 cells with PTP1B-siRNA inhibited the cell proliferation and activation induced by TGF-β1. Additionally, both mRNA and protein of PTP1B were dramatically decreased in inactivated HSCs after treated with adipogenic differentiation mixture (MDI). Over-expression of PTP1B hindered the inactivation of HSC-T6 cells induced by MDI. These observations revealed a regulatory role of PTP1B in liver fibrosis and implied PTP1B as a potential therapeutic target. - Highlights: • The expression of PTP1B in the fibrotic livers and recovery livers • The expression of PTP1B in activated and inactivated HSCs • Blockade of PTP1B inhibited the TGF-β1-induced proliferation and activation of HSCs. • Over-expression of PTP1B abolished the inactivation of HSCs induced by MDI.

Effect of WeiJia on carbon tetrachloride induced chronic liver injury

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Cheung, Pik-Yuen; Zhang, Qi; Zhang, Ya-Ou; Bai, Gan-Rong; Lin, Marie Chia-Mi; Chan, Bernard; Fong, Chi-Chun; Shi, Lin; Shi, Yue-Feng; Chun, Jay; Kung, Hsiang-Fu; Yang, Mengsu

2006-01-01

AIM: To study the effect of WeiJia on chronic liver injury using carbon tetrachloride (CCl4) induced liver injury animal model. METHODS: Wistar rats weighing 180-220g were randomly divided into three groups: normal control group (Group A), CCl4 induced liver injury control group (Group B) and CCl4 induction with WeiJia treatment group (Group C). Each group consisted of 14 rats. Liver damage and fibrosis was induced by subcutaneous injection with 40% CCl4 in olive oil at 3 mL/kg body weight twice a week for eight weeks for Groups B and C rats whereas olive oil was used for Group A rats. Starting from the third week, Group C rats also received daily intraperitoneal injection of WeiJia at a dose of 1.25 μg/kg body weight. Animals were sacrificed at the fifth week (4 male, 3 female), and eighth week (4 male, 3 female) respectively. Degree of fibrosis were measured and serological markers for liver fibrosis and function including hyaluronic acid (HA), type IV collagen (CIV), γ-glutamyl transferase (γ-GT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined. Alpha smooth muscle actin (α-SMA) and proliferating cell nuclear antigen (PCNA) immunohistochemistry were also performed. RESULTS: CCl4 induction led to the damage of liver and development of fibrosis in Group B and Group C rats when compared to Group A rats. The treatment of WeiJia in Group C rats could reduce the fibrosis condition significantly compared to Group B rats. The effect could be observed after three weeks of treatment and was more obvious after eight weeks of treatment. Serum HA, CIV, ALT, AST and γ-GT levels after eight weeks of treatment for Group C rats were 58±22 µg/L (P0.05) respectively, similar to normal control group (Group A), but significantly different from CCl4 induced liver injury control group (Group B). An increase in PCNA and decrease in α-SMA expression level was also observed. CONCLUSION: WeiJia could improve liver function and reduce liver

Comparative retention of fission fragment 147Pm in regenerated and fetal liver on induction of chromosome aberrations in these cells

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Zhu Shoupeng; Zheng Siying; Wang Liuyi; Yang Shujin

1989-01-01

The purpose of the present study is to ascertain comparative retention of fission fragment 147 Pm in regenerated and fetal liver on induction of chromosome aberrations in these cells. The results indicated that retention of 147 Pm in regenerated liver was about 700 times than in fetal liver. The cumulative absorption dose in regenerated liver was about 2.87 Gy, while in fetal liver-only 0.004 Gy. Under the same conditions, the incidence rate of chromosome aberrations in regenerated liver cells induced by 147 Pm was 50.2%, and in fetal liver cells-about 28.3%. It should be concluded that the radiosensitivity to 147 Pm was not uniform among the regenerated and fetal liver cells. The study suggested that fetal liver cells show to be more radiosensitive to 147 Pm than regenerated liver cells. Among the type of aberrations in both cells induced by 147 Pm, chromatid breakages were predominant, accompanied with a few chromosome breakages

Etanercept blocks inflammatory responses orchestrated by TNF-α to promote transplanted cell engraftment and proliferation in rat liver

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Viswanathan, Preeti; Kapoor, Sorabh; Kumaran, Vinay; Joseph, Brigid; Gupta, Sanjeev

2014-01-01

Engraftment of transplanted cells is critical for liver-directed cell therapy but most transplanted cells are rapidly cleared from liver sinusoids by proinflammatory cytokines/chemokines/receptors after activation of neutrophils or Kupffer cells. To define whether TNF-α served roles in cell-transplantation-induced hepatic inflammation, we used TNF-α antagonist, etanercept, for studies in syngeneic rat hepatocyte transplantation systems. After cell transplantation, multiple cytokines/chemokines/receptors were overexpressed, whereas etanercept prior to cell transplantation essentially normalized these responses. Moreover, ETN downregulated cell transplantation-induced intrahepatic release of secretory cytokines, such as high mobility group box 1. These effects of etanercept decreased cell transplantation-induced activation of neutrophils but not of Kupffer cells. Transplanted cell engraftment improved by several-fold in etanercept-treated animals. These gains in cell engraftment were repeatedly realized after pretreatment of animals with etanercept before multiple cell transplantation sessions. Transplanted cell numbers did not change over time indicating absence of cell proliferation after etanercept alone. By contrast, in animals preconditioned with retrorsine and partial hepatectomy, cell transplantation after etanercept pretreatment significantly accelerated liver repopulation compared with control rats. We concluded that TNF-α played a major role in orchestrating cell transplantation-induced inflammation through regulation of multiple cytokines/chemokines/receptor expression. As TNF-α antagonism by etanercept decreased transplanted cell clearance, improved cell engraftment and accelerated liver repopulation, this pharmacological approach to control hepatic inflammation will help optimize clinical strategies for liver cell therapy. PMID:24844924

Chronic Uridine Administration Induces Fatty Liver and Pre-Diabetic Conditions in Mice.

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Yasuyo Urasaki

Full Text Available Uridine is a pyrimidine nucleoside that exerts restorative functions in tissues under stress. Short-term co-administration of uridine with multiple unrelated drugs prevents drug-induced liver lipid accumulation. Uridine has the ability to modulate liver metabolism; however, the precise mechanism has not been delineated. In this study, long-term effects of uridine on liver metabolism were examined in both HepG2 cell cultures and C57BL/6J mice. We report that uridine administration was associated with O-GlcNAc modification of FOXO1, increased gluconeogenesis, reduced insulin signaling activity, and reduced expression of a liver-specific fatty acid binding protein FABP1. Long-term uridine feeding induced systemic glucose intolerance and severe liver lipid accumulation in mice. Our findings suggest that the therapeutic potentials of uridine should be designed for short-term acute administration.

Abacavir-induced liver toxicity

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Maria Diletta Pezzani

2016-09-01

Full Text Available Abacavir-induced liver toxicity is a rare event almost exclusively occurring in HLA B*5701-positive patients. Herein, we report one case of abnormal liver function tests occurring in a young HLA B*5701-negative woman on a stable nevirapine-based regimen with no history of liver problems or alcohol abuse after switching to abacavir from tenofovir. We also investigated the reasons for abacavir discontinuation in a cohort of patients treated with abacavir-lamivudine-nevirapine.

In situ targeting of dendritic cells sets tolerogenic environment and ameliorates CD4+ T-cell response in the postischemic liver.

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Funken, Dominik; Ishikawa-Ankerhold, Hellen; Uhl, Bernd; Lerchenberger, Maximilian; Rentsch, Markus; Mayr, Doris; Massberg, Steffen; Werner, Jens; Khandoga, Andrej

2017-11-01

CD4 + T cells recruited to the liver play a key role in the pathogenesis of ischemia/reperfusion (I/R) injury. The mechanism of their activation during alloantigen-independent I/R is not completely understood. We hypothesized that liver-resident dendritic cells (DCs) interact with CD4 + T cells in the postischemic liver and that modulation of DCs or T-cell-DC interactions attenuates liver inflammation. In mice, warm hepatic I/R (90/120-240 min) was induced. Tolerogenic DCs were generated in situ by pretreatment of animals with the vitamin D analog paricalcitol. A mAb-CD44 was used for blockade of CD4 + T-cell-DC interactions. As shown by 2-photon in vivo microscopy as well as confocal microscopy, CD4 + T cells were closely colocalized with DCs in the postischemic liver. Pretreatment with paricalcitol attenuated I/R-induced maturation of DCs (flow cytometry), CD4 + T-cell recruitment into the liver (intravital microscopy), and hepatocellular/microvascular damage (intravital microscopy, alanine aminotransferase/aspartate aminotransferase, histology). However, interruption of T-cell-DC interaction increased proinflammatory DC maturation and even enhanced tissue damage. Simultaneous treatment with an anti-CD44mAb completely abolished the beneficial effect of paricalcitol on T-cell migration and tissue injury. Our study demonstrates for the first time that hepatic DCs interact with CD4 + T cells in the postischemic liver in vivo ; modulation of DCs and/or generation of tolerogenic DCs attenuates intrahepatic CD4 + T-cell recruitment and reduces I/R injury; and interruption of CD44-dependent CD4 + T-cell-DC interactions enhances tissue injury by preventing the modulatory effect of hepatic DCs on T cells, especially type 1 T helper effector cells. Thus, hepatic DCs are strongly involved in the promotion of CD4 + T-cell-dependent postischemic liver inflammation.-Funken, D., Ishikawa-Ankerhold, H., Uhl, B., Lerchenberger, M., Rentsch, M., Mayr, D., Massberg, S., Werner, J

Involvement of immune-related factors in diclofenac-induced acute liver injury in mice

International Nuclear Information System (INIS)

Yano, Azusa; Higuchi, Satonori; Tsuneyama, Koichi; Fukami, Tatsuki; Nakajima, Miki; Yokoi, Tsuyoshi

2012-01-01

Drug-induced liver injury (DILI) is a major safety concern in drug development and clinical drug therapy. However, the underlying mechanism of DILI is little known. It is difficult to predict DILI in humans due to the lack of experimental animal models. Diclofenac, a non-steroidal anti-inflammatory drug rarely causes severe liver injury in human, but there is some evidence for immunoallergic idiosyncratic reactions. In this study, the mechanism of diclofenac-induced liver injury in mice was investigated. First, we established the dosing condition for liver injury in normal mice. Plasma ALT and AST levels were significantly increased in diclofenac-administered (80 mg/kg, i.p.) mice in a dose- and time-dependent manner. Among several interleukins (ILs) and chemokines, mRNA expression of helper T (Th) 17 cell-mediated factors, such as retinoid orphan receptor (ROR)-γt, and signal transducers and activators of transcription factor (STAT) 3 in the liver, and the plasma IL-17 level were significantly increased. Neutralization of IL-17 tended to suppress the hepatotoxicity of diclofenac, suggesting that IL-17 was partly involved. Gadolinium chloride (GdCl 3 ) administration demonstrated that Kupffer cells are not likely to be involved in diclofenac hepatotoxicity. Hepatic expressions of IL-1β mRNA and plasma IL-1β were significantly increased soon after the diclofenac administration. Then, the results of an in vivo neutralization study of IL-1β suggested that IL-1β was involved early in the time of pathogenesis of the diclofenac-induced liver injury. In conclusion, we firstly developed a diclofenac-induced acute liver injury model in normal mice, and the involvement of IL-17 and IL-1β was clarified.

Montelukast induced acute hepatocellular liver injury

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Harugeri A

2009-01-01

Full Text Available A 46-year-old male with uncontrolled asthma on inhaled albuterol and formoterol with budesonide was commenced on montelukast. He developed abdominal pain and jaundice 48 days after initiating montelukast therapy. His liver tests showed an increase in serum total bilirubin, conjugated bilirubin, aspartate aminotranferase, alanine aminotranferase, and alkaline phosphatase. The patient was evaluated for possible non-drug related liver injury. Montelukast was discontinued suspecting montelukast induced hepatocellular liver injury. Liver tests began to improve and returned to normal 55 days after drug cessation. Causality of this adverse drug reaction by the Council for International Organizations of Medical Sciences or Roussel Uclaf Causality Assessment Method (CIOMS or RUCAM and Naranjo′s algorithm was ′probable′. Liver tests should be monitored in patients receiving montelukast and any early signs of liver injury should be investigated with a high index of suspicion for drug induced liver injury.

Putrescine treatment reverses α-tocopherol-induced desynchronization of polyamine and retinoid metabolism during rat liver regeneration

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Lourdes Sánchez-Sevilla

2016-10-01

Full Text Available Abstract Background The pre-treatment with α-tocopherol inhibits progression of rat liver proliferation induced by partial hepatectomy (PH, by decreasing and/or desynchronizing cyclin D1 expression and activation into the nucleus, activation and nuclear translocation of STAT-1 and -3 proteins and altering retinoid metabolism. Interactions between retinoic acid and polyamines have been reported in the PH-induced rat liver regeneration. Therefore, we evaluated the effect of low dosage of α-tocopherol on PH-induced changes in polyamine metabolism. Methods This study evaluated the participation of polyamine synthesis and metabolism during α-tocopherol-induced inhibition of rat liver regeneration. In PH-rats (Wistar treated with α-tocopherol and putrescine, parameters indicative of cell proliferation, lipid peroxidation, ornithine decarboxylase expression (ODC, and polyamine levels, were determined. Results Pre-treatment with α-tocopherol to PH-animals exerted an antioxidant effect, shifting earlier the increased ODC activity and expression, temporally affecting polyamine synthesis and ornithine metabolism. Whereas administration of putrescine induced minor changes in PH-rats, the concomitant treatment actually counteracted most of adverse actions exerted by α-tocopherol on the remnant liver, restituting its proliferative potential, without changing its antioxidant effect. Putrescine administration to these rats was also associated with lower ODC expression and activity in the proliferating liver, but the temporally shifting in the amount of liver polyamines induced by α-tocopherol, was also “synchronized” by the putrescine administration. The latter is supported by the fact that a close relationship was observed between fluctuations of polyamines and retinoids. Conclusions Putrescine counteracted most adverse actions exerted by α-tocopherol on rat liver regeneration, restoring liver proliferative potential and restituting the decreased

Betatrophin: A liver-derived hormone for the pancreatic β-cell proliferation.

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Raghow, Rajendra

2013-12-15

The pancreatic β-cell failure which invariably accompanies insulin resistance in the liver and skeletal muscle is a hallmark of type-2 diabetes mellitus (T2DM). The persistent hyperglycemia of T2DM is often treated with anti-diabetic drugs with or without subcutaneous insulin injections, neither of which mimic the physiological glycemic control seen in individuals with fully functional pancreas. A sought after goal for the treatment of T2DM has been to harness the regenerative potential of pancreatic β-cells that might obviate a need for exogenous insulin injections. A new study towards attaining this aim was reported by Yi et al, who have characterized a liver-derived protein, named betatrophin, capable of inducing pancreatic β-cell proliferation in mice. Using a variety of in vitro and in vivo methods, Yi et al, have shown that betatrophin was expressed mainly in the liver and adipose tissue of mice. Exogenous expression of betatrophin in the liver led to dramatic increase in the pancreatic β-cell mass and higher output of insulin in mice that also concomitantly elicited improved glucose tolerance. The authors discovered that betatrophin was also present in the human plasma. Surprisingly, betatrophin has been previously described by three other names, i.e., re-feeding-induced fat and liver protein, lipasin and atypical angiopoeitin-like 8, by three independent laboratories, as nutritionally regulated liver-enriched factors that control serum triglyceride levels and lipid metabolism. Yi et al demonstration of betatrophin, as a circulating hormone that regulates β-cell proliferation, if successfully translated in the clinic, holds the potential to change the course of current therapies for diabetes.

Differentiation of human-induced pluripotent stem cell under flow conditions to mature hepatocytes for liver tissue engineering

DEFF Research Database (Denmark)

Starokozhko, Viktoriia; Hemmingsen, Mette; Larsen, Layla

2018-01-01

and to perform functional comparisons with fresh human precision-cut liver slices (hPCLS), an excellent benchmark for the human liver in vivo. The majority of the mRNA expression of CYP isoenzymes and transporters and the tested CYP activities, Phase II metabolism, and albumin, urea, and bile acid synthesis...... in the hiPSC-derived cells reached values that overlap those of hPCLS, which indicates a higher degree of hepatic differentiation than observed until now. Differentiation under flow compared with static conditions had a strong inducing effect on Phase II metabolism and suppressed AFP expression but resulted...... in slightly lower activity of some of the Phase I metabolism enzymes. Gene expression data indicate that hiPSCs differentiated into both hepatic and biliary directions. In conclusion, the hiPSC differentiated under flow conditions towards hepatocytes express a wide spectrum of liver functions at levels...

Mesenchymal Stem Cells Enhance Liver Regeneration via Improving Lipid Accumulation and Hippo Signaling

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Yang Liu

2018-01-01

Full Text Available The liver has the potential to regenerate after injury. It is a challenge to improve liver regeneration (LR after liver resection in clinical practice. Bone morrow-derived mesenchymal stem cells (MSCs have shown to have a role in various liver diseases. To explore the effects of MSCs on LR, we established a model of 70% partial hepatectomy (PHx. Results revealed that infusion of MSCs could improve LR through enhancing cell proliferation and cell growth during the first 2 days after PHx, and MSCs could also restore liver synthesis function. Infusion of MSCs also improved liver lipid accumulation partly via mechanistic target of rapamycin (mTOR signaling and enhanced lipid β-oxidation support energy for LR. Rapamycin-induced inhibition of mTOR decreased liver lipid accumulation at 24 h after PHx, leading to impaired LR. And after infusion of MSCs, a proinflammatory environment formed in the liver, evidenced by increased expression of IL-6 and IL-1β, and thus the STAT3 and Hippo-YAP pathways were activated to improve cell proliferation. Our results demonstrated the function of MSCs on LR after PHx and provided new evidence for stem cell therapy of liver diseases.

Hepatitis B virus induces IL-23 production in antigen presenting cells and causes liver damage via the IL-23/IL-17 axis.

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Qinghong Wang

Full Text Available IL-23 regulates myriad processes in the innate and adaptive immune systems, and is a critical mediator of the proinflammatory effects exerted by Th17 cells in many diseases. In this study, we investigated whether and how hepatitis B virus (HBV causes liver damage directly through the IL-23 signaling pathway. In biopsied liver tissues from HBV-infected patients, expression of both IL-23 and IL-23R was remarkably elevated. In vivo observations also indicated that the main sources of IL-23 were myeloid dendritic cells (mDCs and macrophages. Analysis of in vitro differentiated immature DCs and macrophages isolated from healthy donors revealed that the HBV surface antigen (HBsAg efficiently induces IL-23 secretion in a mannose receptor (MR-dependent manner. Culture with an endosomal acidification inhibitor and the dynamin inhibitor showed that, upon binding to the MR, the HBsAg is taken up by mDCs and macrophages through an endocytosis mechanism. In contrast, although the HBV core antigen (HBcAg can also stimulate IL-23 secretion from mDCs, the process was MR- and endocytosis-independent. In addition, IL-23 was shown to be indispensible for HBsAg-stimulated differentiation of naïve CD4(+ T cells into Th17 cells, which were determined to be the primary source of IL-17 in HBV-infected livers. The cognate receptor, IL-17R, was found to exist on the hepatic stellate cells and mDCs, both of which might represent the potential target cells of IL-17 in hepatitis B disease. These data provide novel insights into a yet unrecognized mechanism of HBV-induced hepatitis, by which increases in IL-23 expression, through an MR/endocytosis-dependent or -independent manner, produce liver damage through the IL-23/IL-17 axis.

Pathological Lesions and Inducible Nitric Oxide Synthase Expressions in the Liver of Mice Experimentally Infected with Clonorchis sinensis.

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Yang, Qing-Li; Shen, Ji-Qing; Xue, Yan; Cheng, Xiao-Bing; Jiang, Zhi-Hua; Yang, Yi-Chao; Chen, Ying-Dan; Zhou, Xiao-Nong

2015-12-01

The nitric oxide (NO) formation and intrinsic nitrosation may be involved in the possible mechanisms of liver fluke-associated carcinogenesis. We still do not know much about the responses of inducible NO synthase (iNOS) induced by Clonorchis sinensis infection. This study was conducted to explore the pathological lesions and iNOS expressions in the liver of mice with different infection intensity levels of C. sinensis. Extensive periductal inflammatory cell infiltration, bile duct hyperplasia, and fibrosis were commonly observed during the infection. The different pathological responses in liver tissues strongly correlated with the infection intensity of C. sinensis. Massive acute spotty necrosis occurred in the liver parenchyma after a severe infection. The iNOS activity in liver tissues increased, and iNOS-expressing cells with morphological differences were observed after a moderate or severe infection. The iNOS-expressing cells in liver tissues had multiple origins.

Role of liver progenitors in liver regeneration.

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Best, Jan; Manka, Paul; Syn, Wing-Kin; Dollé, Laurent; van Grunsven, Leo A; Canbay, Ali

2015-02-01

During massive liver injury and hepatocyte loss, the intrinsic regenerative capacity of the liver by replication of resident hepatocytes is overwhelmed. Treatment of this condition depends on the cause of liver injury, though in many cases liver transplantation (LT) remains the only curative option. LT for end stage chronic and acute liver diseases is hampered by shortage of donor organs and requires immunosuppression. Hepatocyte transplantation is limited by yet unresolved technical difficulties. Since currently no treatment is available to facilitate liver regeneration directly, therapies involving the use of resident liver stem or progenitor cells (LPCs) or non-liver stem cells are coming to fore. LPCs are quiescent in the healthy liver, but may be activated under conditions where the regenerative capacity of mature hepatocytes is severely impaired. Non-liver stem cells include embryonic stem cells (ES cells) and mesenchymal stem cells (MSCs). In the first section, we aim to provide an overview of the role of putative cytokines, growth factors, mitogens and hormones in regulating LPC response and briefly discuss the prognostic value of the LPC response in clinical practice. In the latter section, we will highlight the role of other (non-liver) stem cells in transplantation and discuss advantages and disadvantages of ES cells, induced pluripotent stem cells (iPS), as well as MSCs.

Carvedilol Improves Inflammatory Response, Oxidative Stress and Fibrosis in the Alcohol-Induced Liver Injury in Rats by Regulating Kuppfer Cells and Hepatic Stellate Cells.

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Raimundo Fernandes de Araújo Júnior

Full Text Available To evaluate the anti-inflammatory, anti-oxidant and antifibrotic effects of carvedilol (CARV in rats with ethanol-induced liver injury.Liver injury was induced by gavage administration of alcohol (7 g/kg for 28 consecutive days. Eighty Wistar rats were pretreated with oral CARV at 1, 3, or 5 mg/kg or with saline 1 h before exposure to alcohol. Liver homogenates were assayed for interleukin (IL-1β, IL-10, and tumor necrosis factor (TNF-α level as well as for myeloperoxidase (MPO activity and malonyldialdehyde (MDA and glutathione (GSH levels. Serum aspartate aminotransferase (AST activity and liver triglyceride (TG levels were also assayed. Immunohistochemical analyses of cyclooxygenase 2 (COX-2, receptor activator of nuclear factor kappa-B/ligand (RANK/RANKL, suppressor of cytokine signalling (SOCS1, the Kupffer cell marker IBA-1 (ionized calcium-binding adaptor molecule 1, intercellular adhesion molecule 1 (ICAM-1, superoxide dismutase (SOD-1, and glutathione peroxidase (GPx-1 expression were performed. Confocal microscopy analysis of IL-1β and NF-κB expression and real-time quantitative PCR analysis for TNFα, PCI, PCIII, and NF-κB were performed.CARV treatment (5 mg/kg during the alcohol exposure protocol was associated with reduced steatosis, hepatic cord degeneration, fibrosis and necrosis, as well as reduced levels of AST (p < 0.01, ALT (p < 0.01, TG (p < 0.001, MPO (p < 0.001, MDA (p < 0.05, and proinflammatory cytokines (IL-1β and TNF-α, both p < 0.05, and increased levels of the anti-inflammatory cytokine IL-10 (p < 0.001 and GSH (p < 0.05, compared to the alcohol-only group. Treatment with CARV 5 mg/kg also reduced expression levels of COX-2, RANK, RANKL, IBA-1, and ICAM-1 (all p < 0.05, while increasing expression of SOCS1, SOD-1, and GPx-1 (all p < 0.05 and decreasing expression of IL-1β and NF-κB (both, p < 0.05. Real-time quantitative PCR analysis showed that mRNA production of TNF-α, procollagen type I (PCI, procollagen

Involvement of immune-related factors in diclofenac-induced acute liver injury in mice.

Science.gov (United States)

Yano, Azusa; Higuchi, Satonori; Tsuneyama, Koichi; Fukami, Tatsuki; Nakajima, Miki; Yokoi, Tsuyoshi

2012-03-11

Drug-induced liver injury (DILI) is a major safety concern in drug development and clinical drug therapy. However, the underlying mechanism of DILI is little known. It is difficult to predict DILI in humans due to the lack of experimental animal models. Diclofenac, a non-steroidal anti-inflammatory drug rarely causes severe liver injury in human, but there is some evidence for immunoallergic idiosyncratic reactions. In this study, the mechanism of diclofenac-induced liver injury in mice was investigated. First, we established the dosing condition for liver injury in normal mice. Plasma ALT and AST levels were significantly increased in diclofenac-administered (80 mg/kg, i.p.) mice in a dose- and time-dependent manner. Among several interleukins (ILs) and chemokines, mRNA expression of helper T (Th) 17 cell-mediated factors, such as retinoid orphan receptor (ROR)-γt, and signal transducers and activators of transcription factor (STAT) 3 in the liver, and the plasma IL-17 level were significantly increased. Neutralization of IL-17 tended to suppress the hepatotoxicity of diclofenac, suggesting that IL-17 was partly involved. Gadolinium chloride (GdCl₃) administration demonstrated that Kupffer cells are not likely to be involved in diclofenac hepatotoxicity. Hepatic expressions of IL-1β mRNA and plasma IL-1β were significantly increased soon after the diclofenac administration. Then, the results of an in vivo neutralization study of IL-1β suggested that IL-1β was involved early in the time of pathogenesis of the diclofenac-induced liver injury. In conclusion, we firstly developed a diclofenac-induced acute liver injury model in normal mice, and the involvement of IL-17 and IL-1β was clarified. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Natural Killer cells and liver fibrosis

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Frank eFasbender

2016-01-01

Full Text Available In the 40 years since the discovery of Natural Killer (NK cells it has been well established that these innate lymphocytes are important for early and effective immune responses against transformed cells and infections with different pathogens. In addition to these classical functions of NK cells, we now know that they are part of a larger family of innate lymphoid cells and that they can even mediate memory-like responses. Additionally, tissue resident NK cells with distinct phenotypical and functional characteristics have been identified. Here we focus on the phenotype of different NK cell subpopulations that can be found in the liver and summarize the current knowledge about the functional role of these cells with a special emphasis on liver fibrosis. NK cell cytotoxicity can contribute to liver damage in different forms of liver disease. However, NK cells can limit liver fibrosis by killing hepatic stellate cell-derived myofibroblasts, which play a key role in this pathogenic process. Therefore, liver NK cells need to be tightly regulated in order to balance these beneficial and pathological effects.

Dihydroartemisinin alleviates bile duct ligation-induced liver fibrosis and hepatic stellate cell activation by interfering with the PDGF-βR/ERK signaling pathway.

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Chen, Qin; Chen, Lianyun; Kong, Desong; Shao, Jiangjuan; Wu, Li; Zheng, Shizhong

2016-05-01

Liver fibrosis represents a frequent event following chronic insult to trigger wound healing responses in the liver. Activation of hepatic stellate cells (HSCs), which is a pivotal event during liver fibrogenesis, is accompanied by enhanced expressions of a series of marker proteins and pro-fibrogenic signaling molecules. Artemisinin, a powerful antimalarial medicine, is extracted from the Chinese herb Artemisia annua L., and can inhibit the proliferation of cancer cells. Dihydroartemisinin (DHA), the major active metabolite of artemisinin, is able to attenuate lung injury and fibrosis. However, the effect of DHA on liver fibrosis remains unclear. The aim of this study was to investigate the effect of DHA on bile duct ligation-induced injury and fibrosis in rats. DHA improved the liver histological architecture and attenuated collagen deposition in the fibrotic rat liver. Experiments in vitro showed that DHA inhibited the proliferation of HSCs and arrested the cell cycle at the S checkpoint by altering several cell-cycle regulatory proteins. Moreover, DHA reduced the protein expressions of a-SMA, α1 (I) collagen and fibronectin, being associated with interference of the platelet-derived growth factor β receptor (PDGF-βR)-mediated ERK pathway. These data collectively revealed that DHA relieved liver fibrosis possibly by targeting HSCs via the PDGF-βR/ERK pathway. DHA may be a therapeutic antifibrotic agent for the treatment of hepatic fibrosis. Copyright © 2016 Elsevier B.V. All rights reserved.

Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure

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Honglei eWeng

2015-06-01

Full Text Available Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called second pathway of liver regeneration. The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure.

Science.gov (United States)

Weng, Hong-Lei; Cai, Xiaobo; Yuan, Xiaodong; Liebe, Roman; Dooley, Steven; Li, Hai; Wang, Tai-Ling

2015-01-01

Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called "second pathway of liver regeneration." The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

Complement and alcoholic liver disease: role of C1q in the pathogenesis of ethanol-induced liver injury in mice.

Science.gov (United States)

Cohen, Jessica I; Roychowdhury, Sanjoy; McMullen, Megan R; Stavitsky, Abram B; Nagy, Laura E

2010-08-01

Complement is involved in the development of alcoholic liver disease in mice; however, the mechanisms for complement activation during ethanol exposure have not been identified. C1q, the recognition subunit of the first complement component, binds to apoptotic cells, thereby activating the classical complement pathway. Because ethanol exposure increases hepatocellular apoptosis, we hypothesized that ethanol-induced apoptosis would lead to activation of complement via the classical pathway. Wild-type and C1qa-/- mice were allowed free access to ethanol-containing diets or pair-fed control diets for 4 or 25 days. Ethanol feeding for 4 days increased apoptosis of Kupffer cells in both wild-type and C1qa-/- mice. Ethanol-induced deposition of C1q and C3b/iC3b/C3c was colocalized with apoptotic Kupffer cells in wild-type, but not C1qa-/-, mice. Furthermore, ethanol-induced increases in tumor necrosis factor-alpha and interleukin-6 expression at this early time point were suppressed in C1q-deficient mice. Chronic ethanol feeding (25 days) increased steatosis, hepatocyte apoptosis, and activity of serum alanine and aspartate aminotransferases in wild-type mice. These markers of hepatocyte injury were attenuated in C1qa-/- mice. In contrast, chronic ethanol (25 days)-induced increases in cytochrome P450 2E1 expression and oxidative stress did not differ between wild-type and C1qa-/- mice. For the first time, these data indicate that ethanol activates the classical complement pathway via C1q binding to apoptotic cells in the liver and that C1q contributes to the pathogenesis of ethanol-induced liver injury. Copyright (c) 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

Concomitant apoptosis and regeneration of liver cells as a mechanism of liver-tumor promotion by β-naphthoflavone involving TNFα-signaling due to oxidative cellular stress in rats

International Nuclear Information System (INIS)

Kuwata, Kazunori; Shibutani, Makoto; Hayashi, Hitomi; Shimamoto, Keisuke; Hayashi, Shim-Mo; Suzuki, Kazuhiko; Mitsumori, Kunitoshi

2011-01-01

β-Naphthoflavone (BNF) is a strong inducer of cytochrome P450 1A enzymes, and exerts liver tumor-promoting activity through enhancement of oxidative stress responses in rats. This study investigated the role of the tissue environment surrounding hepatocellular preneoplastic lesions in the early tumor-promotion stage by BNF, using enzymatically modified isoquercitrin (EMIQ) as an anti-oxidative chemopreventive agent. Male F344 rats were fed a diet containing BNF (0.5%) for 6 weeks, with or without EMIQ (0.2%) in the drinking water, 2 weeks after initiation with N-diethylnitrosamine, and were subjected to two-thirds partial hepatectomy 1 week after starting BNF-promotion. BNF-treatment increased concentrations of liver thiobarbituric acid-reactive substances, single liver cells expressing glutathione S-transferase placental form or heme oxygenase (HO)-1, and concomitant apoptosis and proliferation of liver cells. Transcript upregulation of anti-oxidative enzymes (Aldh1a1 and Nqo1), cell cycle-related molecules (Cdc20 and Cdkn2b) and inflammation-related molecules including proinflammatory cytokines (Ccl2, Col1a1, Il6, Nos2 and Serpine1) was also evident. Furthermore, BNF increased HO-1-expressing Kupffer cells and liver cells expressing tumor necrosis factor receptor 1 (TNFR1) and the TNFR1-associated death domain. Most of these BNF-induced fluctuations disappeared or were suppressed by EMIQ in conjunction with suppression of tumor-promotion. Tnf transcript levels with BNF were also suppressed by EMIQ. These results suggest that BNF-induced oxidative stress causes single liver cell toxicity, allowing subsequent concomitant apoptosis and regeneration involving inflammatory responses including TNFα-signaling, contributing to tumor promotion. Kupffer cells may act to protect against inflammatory stimuli induced as a result of oxidative cellular stress by BNF, causing proinflammatory cytokine level fluctuations.

Surgery-induced reactive oxygen species enhance colon carcinoma cell binding by disrupting the liver endothelial cell lining

NARCIS (Netherlands)

Gül, N.; Bögels, M.; Grewal, S.; van der Meer, A.J.; Rojas, L.B.; Fluitsma, D.M.; van den Tol, M.P.; Hoeben, K.A.; van Marle, J.; de Vries, H.E.; Beelen, R.H.J.; van Egmond, M.

2011-01-01

Objective: Resection of primary colorectal cancer is associated with enhanced risk of development of liver metastases. It was previously demonstrated that surgery initiated an early inflammatory response resulting in elevated tumour cell adhesion in the liver. Because reactive oxygen species (ROS)

Surgery-induced reactive oxygen species enhance colon carcinoma cell binding by disrupting the liver endothelial cell lining

NARCIS (Netherlands)

Gul, N.; Bogels, M.; Grewal, S.; van der Meer, A.J.; Rojas, L.B.; Fluitsma, D.M.; van den Tol, M.P.; Hoeben, K.A.; van Marle, J.; de Vries, H.E.; Beelen, R.H.J.; van Egmond, M.

2011-01-01

Objective Resection of primary colorectal cancer is associated with enhanced risk of development of liver metastases. It was previously demonstrated that surgery initiated an early inflammatory response resulting in elevated tumour cell adhesion in the liver. Because reactive oxygen species (ROS)

Chronic inflammation-elicited liver progenitor cell conversion to liver cancer stem cell with clinical significance.

Science.gov (United States)

Li, Xiao-Feng; Chen, Cheng; Xiang, Dai-Min; Qu, Le; Sun, Wen; Lu, Xin-Yuan; Zhou, Teng-Fei; Chen, Shu-Zhen; Ning, Bei-Fang; Cheng, Zhuo; Xia, Ming-Yang; Shen, Wei-Feng; Yang, Wen; Wen, Wen; Lee, Terence Kin Wah; Cong, Wen-Ming; Wang, Hong-Yang; Ding, Jin

2017-12-01

The substantial heterogeneity and hierarchical organization in liver cancer support the theory of liver cancer stem cells (LCSCs). However, the relationship between chronic hepatic inflammation and LCSC generation remains obscure. Here, we observed a close correlation between aggravated inflammation and liver progenitor cell (LPC) propagation in the cirrhotic liver of rats exposed to diethylnitrosamine. LPCs isolated from the rat cirrhotic liver initiated subcutaneous liver cancers in nonobese diabetic/severe combined immunodeficient mice, suggesting the malignant transformation of LPCs toward LCSCs. Interestingly, depletion of Kupffer cells in vivo attenuated the LCSC properties of transformed LPCs and suppressed cytokeratin 19/Oval cell 6-positive tumor occurrence. Conversely, LPCs cocultured with macrophages exhibited enhanced LCSC properties. We further demonstrated that macrophage-secreted tumor necrosis factor-α triggered chromosomal instability in LPCs through the deregulation of ubiquitin D and checkpoint kinase 2 and enhanced the self-renewal of LPCs through the tumor necrosis factor receptor 1/Src/signal transducer and activator of transcription 3 pathway, which synergistically contributed to the conversion of LPCs to LCSCs. Clinical investigation revealed that cytokeratin 19/Oval cell 6-positive liver cancer patients displayed a worse prognosis and exhibited superior response to sorafenib treatment. Our results not only clarify the cellular and molecular mechanisms underlying the inflammation-mediated LCSC generation but also provide a molecular classification for the individualized treatment of liver cancer. (Hepatology 2017;66:1934-1951). © 2017 by the American Association for the Study of Liver Diseases.

Idiosyncratic Drug-Induced Liver Injury: Is Drug-Cytokine Interaction the Linchpin?

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Roth, Robert A; Maiuri, Ashley R; Ganey, Patricia E

2017-02-01

Idiosyncratic drug-induced liver injury continues to be a human health problem in part because drugs that cause these reactions are not identified in current preclinical testing and because progress in prevention is hampered by incomplete knowledge of mechanisms that underlie these adverse responses. Several hypotheses involving adaptive immune responses, inflammatory stress, inability to adapt to stress, and multiple, concurrent factors have been proposed. Yet much remains unknown about how drugs interact with the liver to effect death of hepatocytes. Evidence supporting hypotheses implicating adaptive or innate immune responses in afflicted patients has begun to emerge and is bolstered by results obtained in experimental animal models and in vitro systems. A commonality in adaptive and innate immunity is the production of cytokines, including interferon-γ (IFNγ). IFNγ initiates cell signaling pathways that culminate in cell death or inhibition of proliferative repair. Tumor necrosis factor-α, another cytokine prominent in immune responses, can also promote cell death. Furthermore, tumor necrosis factor-α interacts with IFNγ, leading to enhanced cellular responses to each cytokine. In this short review, we propose that the interaction of drugs with these cytokines contributes to idiosyncratic drug-induced liver injury, and mechanisms by which this could occur are discussed. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Surgery-induced reactive oxygen species enhance colon carcinoma cell binding by disrupting the liver endothelial cell lining

NARCIS (Netherlands)

Gül, Nuray; Bögels, Marijn; Grewal, Simran; van der Meer, Anne Jan; Rojas, Lucy Baldeon; Fluitsma, Donna M.; van den Tol, M. Petrousjka; Hoeben, Kees A.; van Marle, Jan; de Vries, Helga E.; Beelen, Robert H. J.; van Egmond, Marjolein

2011-01-01

Resection of primary colorectal cancer is associated with enhanced risk of development of liver metastases. It was previously demonstrated that surgery initiated an early inflammatory response resulting in elevated tumour cell adhesion in the liver. Because reactive oxygen species (ROS) are shown to

Research advances in sorafenib-induced apoptotic signaling pathways in liver cancer cells

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ZHANG Chaoya

2016-04-01

Full Text Available Currently, sorafenib is the multi-target inhibitor for the treatment of advanced primary liver cancer, and can effectively prolong the progression-free survival and overall survival in patients with advanced primary liver cancer. The application of sorafenib in the targeted therapy for liver cancer has become a hot topic. Major targets or signaling pathways include Raf/Mek/Erk, Jak/Stat, PI3K/Akt/mTOR, VEGFR and PDGFR, STAT, microRNA, Wnt/β-catenin, autolysosome, and tumor-related proteins, and sorafenib can regulate the proliferation, differentiation, metastasis, and apoptosis of liver cancer cells through these targets. This article reviews the current research on the action of sorafenib on these targets or signaling pathways to provide useful references for further clinical research on sorafenib.

Hepatic overproduction of 13-HODE due to ALOX15 upregulation contributes to alcohol-induced liver injury in mice

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Zhang, Wenliang; Zhong, Wei; Sun, Qian; Sun, Xinguo; Zhou, Zhanxiang

2017-01-01

Chronic alcohol feeding causes lipid accumulation and apoptosis in the liver. This study investigated the role of bioactive lipid metabolites in alcohol-induced liver damage and tested the potential of targeting arachidonate 15-lipoxygenase (ALOX15) in treating alcoholic liver disease (ALD). Results showed that chronic alcohol exposure induced hepatocyte apoptosis in association with increased hepatic 13-HODE. Exposure of 13-HODE to Hepa-1c1c7 cells induced oxidative stress, ER stress and apo...

Drug-induced liver injury

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Nielsen, Mille Bækdal; Ytting, Henriette; Skalshøi Kjær, Mette

2017-01-01

OBJECTIVE: The idiosyncratic subtype of drug-induced liver injury (DILI) is a rare reaction to medical treatment that in severe cases can lead to acute liver failure and death. The aim of this study was to describe the presentation and outcome of DILI and to identify potential predictive factors...... that DILI may be severe and run a fatal course, and that bilirubin and INR levels may predict poor outcome....

Completion of hepatitis C virus replication cycle in heterokaryons excludes dominant restrictions in human non-liver and mouse liver cell lines.

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Anne Frentzen

2011-04-01

Full Text Available Hepatitis C virus (HCV is hepatotropic and only infects humans and chimpanzees. Consequently, an immunocompetent small animal model is lacking. The restricted tropism of HCV likely reflects specific host factor requirements. We investigated if dominant restriction factors expressed in non-liver or non-human cell lines inhibit HCV propagation thus rendering these cells non-permissive. To this end we explored if HCV completes its replication cycle in heterokaryons between human liver cell lines and non-permissive cell lines from human non-liver or mouse liver origin. Despite functional viral pattern recognition pathways and responsiveness to interferon, virus production was observed in all fused cells and was only ablated when cells were treated with exogenous interferon. These results exclude that constitutive or virus-induced expression of dominant restriction factors prevents propagation of HCV in these cell types, which has important implications for HCV tissue and species tropism. In turn, these data strongly advocate transgenic approaches of crucial human HCV cofactors to establish an immunocompetent small animal model.

In Vitro and In Vivo Hepatic Differentiation of Adult Somatic Stem Cells and Extraembryonic Stem Cells for Treating End Stage Liver Diseases

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Chenxia Hu

2015-01-01

Full Text Available The shortage of liver donors is a major handicap that prevents most patients from receiving liver transplantation and places them on a waiting list for donated liver tissue. Then, primary hepatocyte transplantation and bioartificial livers have emerged as two alternative treatments for these often fatal diseases. However, another problem has emerged. Functional hepatocytes for liver regeneration are in short supply, and they will dedifferentiate immediately in vitro after they are isolated from liver tissue. Alternative stem-cell-based therapeutic strategies, including hepatic stem cells (HSCs, embryonic stem cells (ESCs, induced pluripotent stem cells (iPSCs, and mesenchymal stem cells (MSCs, are more promising, and more attention has been devoted to these approaches because of the high potency and proliferation ability of the cells. This review will focus on the general characteristics and the progress in hepatic differentiation of adult somatic stem cells and extraembryonic stem cells in vitro and in vivo for the treatment of end stage liver diseases. The hepatic differentiation of stem cells would offer an ideal and promising source for cell therapy and tissue engineering for treating liver diseases.

Gene expression profiling of liver cancer stem cells by RNA-sequencing.

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David W Y Ho

/SIGNIFICANCE: The identified genes, such as GPC3 that are distinctly expressed in liver CD90(+CSCs, may be promising gene candidates for HCC therapy without inducing damages to normal liver stem cells.

Gene Expression Profiling of Liver Cancer Stem Cells by RNA-Sequencing

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Lam, Chi Tat; Ng, Michael N. P.; Yu, Wan Ching; Lau, Joyce; Wan, Timothy; Wang, Xiaoqi; Yan, Zhixiang; Liu, Hang; Fan, Sheung Tat

2012-01-01

, such as GPC3 that are distinctly expressed in liver CD90+CSCs, may be promising gene candidates for HCC therapy without inducing damages to normal liver stem cells. PMID:22606345

Systemic agonistic anti-CD40 treatment of tumor bearing mice modulates hepatic myeloid suppressive cells and causes immune-mediated liver damage

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Medina-Echeverz, José; Ma, Chi; Duffy, Austin; Eggert, Tobias; Hawk, Nga; Kleiner, David E.; Korangy, Firouzeh; Greten, Tim F.

2015-01-01

Immune stimulatory monoclonal antibodies are currently evaluated as anti tumor agents. Although overall toxicity appears to be moderate, liver toxicities have been reported and are not completely understood. We studied the effect of systemic CD40 antibody treatment on myeloid cells in spleen and liver. Naïve and tumor-bearing mice were treated systemically with agonistic anti-CD40 antibody. Immune cell subsets in liver and spleen, serum transaminases and liver histologies were analyzed after antibody administration. Nox2−/−, Cd40−/− as well as bone marrow chimeric mice were used to study the mechanism by which agonistic anti-CD40 mediates its effects in vivo. Suppressor function of murine and human tumor-induced myeloid derived suppressive cells was studied upon CD40 ligation. Agonistic CD40 antibody caused liver damage within 24 hours after injection in two unrelated tumor models and mice strains. Using bone marrow chimeras we demonstrated that CD40 antibody-induced hepatitis in tumor-bearing mice was dependent on the presence of CD40-expressing hematopoietic cells. Agonistic CD40 ligation-dependent liver damage was induced by the generation of reactive oxygen species. Furthermore, agonistic CD40 antibody resulted in increased CD80 and CD40 positive liver CD11b+Gr-1+ immature myeloid cells. CD40 ligation on tumor-induced murine and human CD14+HLA-DRlow PBMC from cancer patients reduced their immune suppressor function. Collectively, agonistic CD40 antibody treatment activated tumor-induced, myeloid cells, caused myeloid dependent hepatotoxicity and ameliorated the suppressor function of murine and human MDSC. Collectively, our data suggests that CD40 may mature immunosuppressive myeloid cells and thereby cause liver damage in mice with an accumulation of tumor-induced hepatic MDSC. PMID:25637366

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

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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.

Stellate Cell Activation and Imbalanced Expression of TGF-β1/TGF-β3 in Acute Autoimmune Liver Lesions Induced by ConA in Mice

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Liyun Wang

2017-01-01

Full Text Available Objective. To study the pathogenic feature of liver injury, activation of hepatic stellate cells, and dynamic expression of TGF-β1/TGF-β3 to reveal their role in liver injury induced by ConA. Methods. Mice were randomly divided into control group and ConA treatment group. ConA (20 mg/kg was injected through vena caudalis in ConA treatment group; the controls received the same volume of saline injection. After injection for 2 h, 8 h, 24 h, and 48 h, animals were terminated. Blood, liver, and spleen were harvested. Liver function and histopathology were studied. α-SMA, vimentin, TGF-β1, and TGF-β3 were detected. Results. After ConA injection, liver damage started to increase. Expression of α-SMA, vimentin, TGF-β1, and TGF-β3 was significantly enhanced; all above indicators reached peak at 8 h; but from 24 h after ConA injection, TGF-β3 expression began to decline, while the TGF-β1/TGF-β3 ratio at 48 h was significantly lower than control. Conclusion. (1 Autoimmune liver injury induced by ConA showed time-based features, in which the most serious liver lesions happened at 8 h after ConA injection. (2 Early activation of HSC and imbalance expression of TGF-β1 and TGF-β3 existed in ConA-induced acute autoimmune liver injury, which may be associated with liver dysfunction and the mechanisms of progression to fibrosis.

The Effects of Syzygium samarangense, Passiflora edulis and Solanum muricatum on Alcohol-Induced Liver Injury

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Yu-Jie Zhang

2016-09-01

Full Text Available Previous studies have shown that fruits have different effects on alcohol metabolism and alcohol-induced liver injury. The present work selected three fruits and aimed at studying the effects of Syzygium samarangense, Passiflora edulis and Solanum muricatum on alcohol-induced liver injury in mice. The animals were treated daily with alcohol and fruit juices for fifteen days. Chronic treatment with alcohol increased the levels of aspartate transaminase (AST, alanine transaminase (ALT, total bilirubin (TBIL, triglyceride (TG, malondialdehyde (MDA, and decreased total protein (TP. Histopathological evaluation also showed that ethanol induced extensive fat droplets in hepatocyte cytoplasm. Syzygium samarangense and Passiflora edulis normalized various biochemical parameters. Solanum muricatum increased the level of ALT and induced infiltration of inflammatory cells in the liver. These results strongly suggest that treatment with Syzygium samarangense and Passiflora edulis could protect liver from the injury of alcohol, while Solanum muricatum could aggravate the damage.

The role of Foxp3+ regulatory T cells in liver transplant tolerance.

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Li, W; Carper, K; Zheng, X X; Kuhr, C S; Reyes, J D; Liang, Y; Perkins, D L; Thomson, A W; Perkins, J D

2006-12-01

The liver has long been considered a tolerogenic organ that favors the induction of peripheral tolerance. The mechanisms underlying liver tolerogenicity remain largely undefined. In this study, we characterized Foxp3-expressing CD4+ CD25+ regulatory T cells (Treg) in liver allograft recipients and examined the role of Treg in inherent liver tolerogenicity by employing the mouse spontaneous liver transplant tolerance model. Orthotopic liver transplantation was performed from C57BL/10 (H2b) to C3H/HeJ (H2k) mice. The percentage of CD4+ CD25+ Treg was expanded in the liver grafts and recipient spleens from day 5 up to day 100 posttransplantation, associated with high intracellular Foxp3 and CTLA4 expression. Immunohistochemistry further demonstrated significant numbers of Foxp3+ cells in the liver grafts and recipient spleens and increased transforming growth factor beta expression in the recipient spleens throughout the time courses. Adoptive transfer of spleen cells from the long-term liver allograft survivors significantly prolonged donor heart graft survival. Depletion of recipient CD4+ CD25+ Treg using anti-CD25 monoclonal antibody (250 microg/d) induced acute liver allograft rejection, associated with elevated anti-donor T-cell proliferative responses, CTL and natural killer activities, enhanced interleukin (IL)-2, interferon-gamma, IL-10, and decreased IL-4 production, and decreased T-cell apoptotic activity in anti-CD25-treated recipients. Moreover, CTLA4 blockade by anti-CTLA4 monoclonal antibody administration exacerbated liver graft rejection when combined with anti-CD25 monoclonal antibody. Thus, Foxp3+ CD4+ CD25+ Treg appear to underpin spontaneous acceptance of major histocompatability complex- mismatched liver allografts in mice. CTLA4, IL-4, and apoptosis of alloreactive T cells appear to contribute to the function of Treg and regulation of graft outcome.

Vildagliptin Can Alleviate Endoplasmic Reticulum Stress in the Liver Induced by a High Fat Diet.

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Ma, Xiaoqing; Du, Wenhua; Shao, Shanshan; Yu, Chunxiao; Zhou, Lingyan; Jing, Fei

2018-01-01

Purpose. We investigated whether a DDP-4 inhibitor, vildagliptin, alleviated ER stress induced by a high fat diet and improved hepatic lipid deposition. Methods. C57BL/6 mice received standard chow diet (CD), high fat diet (HFD), and HFD administered with vildagliptin (50 mg/Kg) (V-HFD). After administration for 12 weeks, serum alanine aminotransferase, glucose, cholesterol, triglyceride, and insulin levels were analyzed. Samples of liver underwent histological examination and transmission electron microscopy, real-time PCR for gene expression levels, and western blots for protein expression levels. ER stress was induced in HepG2 cells with palmitic acid and the effects of vildagliptin were investigated. Results. HFD mice showed increased liver weight/body weight (20.27%) and liver triglycerides (314.75%) compared to CD mice, but these decreased by 9.27% and 21.83%, respectively, in V-HFD mice. In the liver, HFD induced the expression of ER stress indicators significantly, which were obviously decreased by vildagliptin. In vitro, the expressions of molecular indicators of ER stress were reduced in HepG2 when vildagliptin was administered. Conclusions. Vildagliptin alleviates hepatic ER stress in a mouse high fat diet model. In HepG2 cells, vildagliptin directly reduced ER stress. Therefore, vildagliptin may be a potential agent for nonalcoholic fatty liver disease.

Kupffer Cells in the Liver

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Dixon, Laura J.; Barnes, Mark; Tang, Hui; Pritchard, Michele T.; Nagy, Laura E.

2016-01-01

Kupffer cells are a critical component of the mononuclear phagocytic system and are central to both the hepatic and systemic response to pathogens. Kupffer cells are reemerging as critical mediators of both liver injury and repair. Kupffer cells exhibit a tremendous plasticity; depending on the local metabolic and immune environment, then can express a range of polarized phenotypes, from the proinflammatory M1 phenotype to the alternative/M2 phenotype. Multiple M2 phenotypes can be distinguished, each involved in the resolution of inflammation and wound healing. Here, we have provided an update on recent research that has contributed to the developing delineation of the contribution of Kupffer cells to different types of liver injury, with an emphasis on alcoholic and nonalcoholic liver diseases. These recent advances in our understanding of Kupffer cell function and regulation will likely provide new insights into the potential for therapeutic manipulation of Kupffer cells to promote the resolution of inflammation and enhance wound healing in liver disease. PMID:23720329

Liver-derived systemic factors drive β-cell hyperplasia in insulin resistant states

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El Ouaamari, Abdelfattah; Kawamori, Dan; Dirice, Ercument; Liew, Chong Wee; Shadrach, Jennifer L.; Hu, Jiang; Katsuta, Hitoshi; Hollister-Lock, Jennifer; Qian, Weijun; Wagers, Amy J.; Kulkarni, Rohit N.

2013-02-21

Integrative organ cross-talk regulates key aspects of energy homeostasis and its dysregulation may underlie metabolic disorders such as obesity and diabetes. To test the hypothesis that cross-talk between the liver and pancreatic islets modulates β-cell growth in response to insulin resistance, we used the Liver-specific Insulin Receptor Knockout (LIRKO) mouse, a unique model that exhibits dramatic islet hyperplasia. Using complementary in vivo parabiosis and transplantation assays, and in vitro islet culture approaches, we demonstrate that humoral, non-neural, non-cell autonomous factor(s) induce β-cell proliferation in LIRKO mice. Furthermore, we report that a hepatocyte-derived factor(s) stimulates mouse and human β-cell proliferation in ex vivo assays, independent of ambient glucose and insulin levels. These data implicate the liver as a critical source of β-cell growth factors in insulin resistant states.

Magnetic targeting of iron-oxide-labeled fluorescent hepatoma cells to the liver

International Nuclear Information System (INIS)

Luciani, Alain; Wilhelm, Claire; Gazeau, Florence; Bruneval, Patrick; Cunin, Patrick; Autret, Gwennhael; Clement, Olivier; Rahmouni, Alain

2009-01-01

The purpose of this study was to determine whether an external magnet field can induce preferential trafficking of magnetically labeled Huh7 hepatoma cells to the liver following liver cell transplantation. Huh7 hepatoma cells were labeled with anionic magnetic nanoparticles (AMNP) and tagged with a fluorescent membrane marker (PKH67). Iron-uptake was measured by magnetophoresis. Twenty C57Bl6 mice received an intrasplenic injection of 2 x 10 6 labeled cells. An external magnet (0.29 T; 25 T/m) was placed over the liver of 13 randomly selected animals (magnet group), while the remaining 7 animals served as controls. MRI (1.5 T) and confocal fluorescence microscopy (CFM) were performed 10 days post-transplantation. The presence and location of labeled cells within the livers were compared in the magnet group and controls, and confronted with histological analysis representing the standard of reference. Mean iron content per cell was 6 pg. Based on histology, labeled cells were more frequently present within recipient livers in the magnet group (p < 0.01) where their distribution was preferentially peri-vascular (p<0.05). MRI and CFM gave similar results for the overall detection of transplanted cells (kappa=0.828) and for the identification of peri-vascular cells (kappa=0.78). Application of an external magnet can modify the trafficking of transplanted cells, especially by promoting the formation of perivascular aggregates. (orig.)

GSK-3β Inhibition Attenuates CLP-Induced Liver Injury by Reducing Inflammation and Hepatic Cell Apoptosis

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Hui Zhang

2014-01-01

Full Text Available Liver dysfunction has been known to occur frequently in cases of sepsis. Excessive inflammation and apoptosis are pathological features of acute liver failure. Recent studies suggest that activation of glycogen synthase kinase- (GSK- 3β is involved in inflammation and apoptosis. We aimed to investigate the protective effects of GSK-3β inhibition on polymicrobial sepsis-induced liver injury and to explore the possible mechanisms. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP, and SB216763 was used to inhibit GSK-3β in C57BL/6 mice. GSK-3β was activated following CLP. Administration of SB216763 decreased mortality, ameliorated liver injury, and reduced hepatic apoptosis. The inhibition of GSK-3β also reduced leukocyte infiltration and hepatic inflammatory cytokine expression and release. Moreover, GSK-3β inhibition suppressed the transcriptional activity of nuclear factor-kappa B (NF-κB but enhanced the transcriptional activity of cAMP response element binding protein (CREB in the liver. In in vitro studies, GSK-3β inhibition reduced inflammatory cytokine production via modulation of NF-κB and CREB signaling pathways in lipopolysaccharide-stimulated macrophages. In conclusion, these findings suggest that GSK-3β blockade protects against CLP-induced liver via inhibition of inflammation by modulating NF-κB and CREB activity and suppression of hepatic apoptosis.

Hyper-IL-15 suppresses metastatic and autochthonous liver cancer by promoting tumour-specific CD8+ T cell responses.

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Cheng, Liang; Du, Xuexiang; Wang, Zheng; Ju, Jianqi; Jia, Mingming; Huang, Qibin; Xing, Qiao; Xu, Meng; Tan, Yi; Liu, Mingyue; Du, Peishuang; Su, Lishan; Wang, Shengdian

2014-12-01

Liver cancer has a very dismal prognosis due to lack of effective therapy. Here, we studied the therapeutic effects of hyper-interleukin15 (hyper-IL-15), which is composed of IL-15 and the sushi domain of the IL-15 receptor α chain, on metastatic and autochthonous liver cancers. Liver metastatic tumour models were established by intraportally injecting syngeneic mice with murine CT26 colon carcinoma cells or B16-OVA melanoma cells. Primary hepatocellular carcinoma (HCC) was induced by diethylnitrosamine (DEN). A hydrodynamics-based gene delivery method was used to achieve sustained hyper-IL-15 expression in the liver. Liver gene delivery of hyper-IL-15 robustly expanded CD8(+) T and NK cells, leading to a long-term (more than 40 days) accumulation of CD8(+) T cells in vivo, especially in the liver. Hyper-IL-15 treatment exerted remarkable therapeutic effects on well-established liver metastatic tumours and even on DEN-induced autochthonous HCC, and these effects were abolished by depletion of CD8(+) T cells but not NK cells. Hyper-IL-15 triggered IL-12 and interferon-γ production and reduced the expression of co-inhibitory molecules on dendritic cells in the liver. Adoptive transfer of T cell receptor (TCR) transgenic OT-1 cells showed that hyper-IL-15 preferentially expanded tumour-specific CD8(+) T cells and promoted their interferon-γ synthesis and cytotoxicity. Liver delivery of hyper-IL-15 provides an effective therapy against well-established metastatic and autochthonous liver cancers in mouse models by preferentially expanding tumour-specific CD8(+) T cells and promoting their anti-tumour effects. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Cocktail of chemical compounds robustly promoting cell reprogramming protects liver against acute injury

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Yuewen Tang

2017-02-01

Full Text Available Abstract Tissue damage induces cells into reprogramming-like cellular state, which contributes to tissue regeneration. However, whether factors promoting the cell reprogramming favor tissue regeneration remains elusive. Here we identified combination of small chemical compounds including drug cocktails robustly promoting in vitro cell reprogramming. We then administrated the drug cocktails to mice with acute liver injuries induced by partial hepatectomy or toxic treatment. Our results demonstrated that the drug cocktails which promoted cell reprogramming in vitro improved liver regeneration and hepatic function in vivo after acute injuries. The underlying mechanism could be that expression of pluripotent genes activated after injury is further upregulated by drug cocktails. Thus our study offers proof-of-concept evidence that cocktail of clinical compounds improving cell reprogramming favors tissue recovery after acute damages, which is an attractive strategy for regenerative purpose.

Bitter melon extract ameliorates palmitate-induced apoptosis via inhibition of endoplasmic reticulum stress in HepG2 cells and high-fat/high-fructose-diet-induced fatty liver

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Hwa Joung Lee

2018-03-01

Full Text Available Background: Bitter melon (BM improves glucose level, lipid homeostasis, and insulin resistance in vivo. However, the preventive mechanism of BM in nonalcoholic fatty liver disease (NAFLD has not been elucidated yet. Aim & Design: To determine the protective mechanism of bitter melon extract (BME, we performed experiments in vitro and in vivo. BME were treated palmitate (PA-administrated HepG2 cells. C57BL/6J mice were divided into two groups: high-fat/high-fructose (HF/HFr without or with BME supplementation (100 mg/kg body weight. Endoplasmic reticulum (ER stress, apoptosis, and biochemical markers were then examined by western blot and real-time PCR analyses. Results: BME significantly decreased expression levels of ER-stress markers (including phospho-eIF2α, CHOP, and phospho-JNK [Jun N-terminal kinases] in PA-treated HepG2 cells. BME also significantly decreased the activity of cleaved caspase-3 (a well known apoptotic-induced molecule and DNA fragmentation. The effect of BME on ER stress–mediated apoptosis in vitro was similarly observed in HF/HFr-fed mice in vivo. BME significantly reduced HF/HFr-induced hepatic triglyceride (TG and serum alanine aminotransferase (ALT as markers of hepatic damage in mice. In addition, BME ameliorated HF/HFr-induced serum TG and serum-free fatty acids. Conclusion: These data indicate that BME has protective effects against ER stress mediated apoptosis in HepG2 cells as well as in HF/HFr-induced fatty liver of mouse. Therefore, BME might be useful for preventing and treating NAFLD.

Inhibition of vascular endothelial growth factor signaling facilitates liver repair from acute ethanol-induced injury in zebrafish

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Changwen Zhang

2016-11-01

Full Text Available Alcoholic liver disease (ALD results from alcohol overconsumption and is among the leading causes of liver-related morbidity and mortality worldwide. Elevated expression of vascular endothelial growth factor (VEGF and its receptors has been observed in ALD, but how it contributes to ALD pathophysiology is unclear. Here, we investigated the impact of VEGF signaling inhibition on an established zebrafish model of acute alcoholic liver injury. Kdrl activity was blocked by chemical inhibitor treatment or by genetic mutation. Exposing 4-day-old zebrafish larvae to 2% ethanol for 24 h induced hepatic steatosis, angiogenesis and fibrogenesis. The liver started self-repair once ethanol was removed. Although inhibiting Kdrl did not block the initial activation of hepatic stellate cells during ethanol treatment, it suppressed their proliferation, extracellular matrix protein deposition and fibrogenic gene expression after ethanol exposure, thus enhancing the liver repair. It also ameliorated hepatic steatosis and attenuated hepatic angiogenesis that accelerated after the ethanol treatment. qPCR showed that hepatic stellate cells are the first liver cell type to increase the expression of VEGF ligand and receptor genes in response to ethanol exposure. Both hepatic stellate cells and endothelial cells, but not hepatic parenchymal cells, expressed kdrl upon ethanol exposure and were likely the direct targets of Kdrl inhibition. Ethanol-induced steatosis and fibrogenesis still occurred in cloche mutants that have hepatic stellate cells but lack hepatic endothelial cells, and Kdrl inhibition suppressed both phenotypes in the mutants. These results suggest that VEGF signaling mediates interactions between activated hepatic stellate cells and hepatocytes that lead to steatosis. Our study demonstrates the involvement of VEGF signaling in regulating sustained liver injuries after acute alcohol exposure. It also provides a proof of principle of using the

Adipose derived mesenchymal stem cells transplantation via portal vein improves microcirculation and ameliorates liver fibrosis induced by CCl4 in rats

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Wang Yu

2012-06-01

Full Text Available Abstract Introduction Adipose derived mesenchymal stem cells (ADMSCs, carrying the similar characteristics to bone marrow mesenchymal stem cells, only much more abundant and easier to obtain, may be a promising treatment for liver fibrosis. We aim to investigate the therapeutic potential of ADMSCs transplantation in liver fibrosis caused by carbon tetrachloride (CCl4 in rats as well as its underlying mechanism, and to further explore the appropriate infusion pathway. Methods ADMSCs were isolated, cultured and identified. Placebo and ADMSCs were transplanted via portal vein and tail vein respectively into carbon tetrachloride (CCl4-induced liver fibrosis rats. Computed tomography (CT perfusion scan and microvessel counts were performed to measure the alteration of liver microcirculation after therapy. Liver function tests and histological findings were estimated. Results CT perfusion scan shown significant decrease of hepatic arterial perfusion index, significant increased portal vein perfusion, total liver perfusion in rats receiving ADMSCs from portal vein, and Factor VIII (FVIII immunohistochemical staining shown significant decrease of microvessels in rats receiving ADMSCs from portal vein, indicating microcirculation improvement in portal vein group. Vascular endothelial growth Factor (VEGF was significantly up-regulated in fibrosis models, and decreased after ADMSCs intraportal transplantation. A significant improvement of liver functional test and histological findings in portal vein group were observed. No significance was found in rats receiving ADMSCs from tail vein. Conclusions ADMSCs have a therapeutic effect against CCl4-mediated liver fibrosis. ADMSCs may benefit the fibrotic liver through alteration of microcirculation, evidenced by CT perfusion scan and down-regulation of VEGF. Intraportal transplantation is a better pathway than tail vein transplantation.

Characterization of two distinct liver progenitor cell subpopulations of hematopoietic and hepatic origins

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Corcelle, V.; Stieger, B.; Gjinovci, A.; Wollheim, C.B.; Gauthier, B.R.

2006-01-01

Despite extensive studies, the hematopoietic versus hepatic origin of liver progenitor oval cells remains controversial. The aim of this study was to determine the origin of such cells after liver injury and to establish an oval cell line. Rat liver injury was induced by subcutaneous insertion of 2-AAF pellets for 7 days with subsequent injection of CCl 4 . Livers were removed 9 to 13 days post-CCl 4 treatment. Immunohistochemistry was performed using anti-c-kit, OV6, Thy1, CK19, AFP, vWF and Rab3b. Isolated non-parenchymal cells were grown on mouse embryonic fibroblast, and their gene expression profile was characterized by RT-PCR. We identified a subpopulation of OV6/CK19/Rab3b-expressing cells that was activated in the periportal region of traumatized livers. We also characterized a second subpopulation that expressed the HSCs marker c-kit but not Thy1. Although we successfully isolated both cell types, OV6/CK19/Rab3b + cells fail to propagate while c-kit + -HSCs appeared to proliferate for up to 7 weeks. Cells formed clusters which expressed c-kit, Thy1 and albumin. Our results indicate that a bona fide oval progenitor cell population resides within the liver and is distinct from c-kit + -HSCs. Oval cells require the hepatic niche to proliferate, while cells mobilized from the circulation proliferate and transdifferentiate into hepatocytes without evidence of cell fusion

CLEC4F is an inducible C-type lectin in F4/80-positive cells and is involved in alpha-galactosylceramide presentation in liver.

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Chih-Ya Yang

Full Text Available CLEC4F, a member of C-type lectin, was first purified from rat liver extract with high binding affinity to fucose, galactose (Gal, N-acetylgalactosamine (GalNAc, and un-sialylated glucosphingolipids with GalNAc or Gal terminus. However, the biological functions of CLEC4F have not been elucidated. To address this question, we examined the expression and distribution of murine CLEC4F, determined its binding specificity by glycan array, and investigated its function using CLEC4F knockout (Clec4f-/- mice. We found that CLEC4F is a heavily glycosylated membrane protein co-expressed with F4/80 on Kupffer cells. In contrast to F4/80, CLEC4F is detectable in fetal livers at embryonic day 11.5 (E11.5 but not in yolk sac, suggesting the expression of CLEC4F is induced as cells migrate from yolk cells to the liver. Even though CLEC4F is not detectable in tissues outside liver, both residential Kupffer cells and infiltrating mononuclear cells surrounding liver abscesses are CLEC4F-positive upon Listeria monocytogenes (L. monocytogenes infection. While CLEC4F has strong binding to Gal and GalNAc, terminal fucosylation inhibits CLEC4F recognition to several glycans such as Fucosyl GM1, Globo H, Bb3∼4 and other fucosyl-glycans. Moreover, CLEC4F interacts with alpha-galactosylceramide (α-GalCer in a calcium-dependent manner and participates in the presentation of α-GalCer to natural killer T (NKT cells. This suggests that CLEC4F is a C-type lectin with diverse binding specificity expressed on residential Kupffer cells and infiltrating monocytes in the liver, and may play an important role to modulate glycolipids presentation on Kupffer cells.

Replicative stress and alterations in cell cycle checkpoint controls following acetaminophen hepatotoxicity restrict liver regeneration.

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Viswanathan, Preeti; Sharma, Yogeshwar; Gupta, Priya; Gupta, Sanjeev

2018-03-05

Acetaminophen hepatotoxicity is a leading cause of hepatic failure with impairments in liver regeneration producing significant mortality. Multiple intracellular events, including oxidative stress, mitochondrial damage, inflammation, etc., signify acetaminophen toxicity, although how these may alter cell cycle controls has been unknown and was studied for its significance in liver regeneration. Assays were performed in HuH-7 human hepatocellular carcinoma cells, primary human hepatocytes and tissue samples from people with acetaminophen-induced acute liver failure. Cellular oxidative stress, DNA damage and cell proliferation events were investigated by mitochondrial membrane potential assays, flow cytometry, fluorescence staining, comet assays and spotted arrays for protein expression after acetaminophen exposures. In experimental groups with acetaminophen toxicity, impaired mitochondrial viability and substantial DNA damage were observed with rapid loss of cells in S and G2/M and cell cycle restrictions or even exit in the remainder. This resulted from altered expression of the DNA damage regulator, ATM and downstream transducers, which imposed G1/S checkpoint arrest, delayed entry into S and restricted G2 transit. Tissues from people with acute liver failure confirmed hepatic DNA damage and cell cycle-related lesions, including restrictions of hepatocytes in aneuploid states. Remarkably, treatment of cells with a cytoprotective cytokine reversed acetaminophen-induced restrictions to restore cycling. Cell cycle lesions following mitochondrial and DNA damage led to failure of hepatic regeneration in acetaminophen toxicity but their reversibility offers molecular targets for treating acute liver failure. © 2018 John Wiley & Sons Ltd.

Proapoptotic Role of Potassium Ions in Liver Cells

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Zhenglin Xia

2016-01-01

Full Text Available Potassium channels are transmembrane proteins that selectively promote the infiltration of potassium ions. The significance of these channels for tumor biology has become obvious. However, the effects of potassium ions on the tumor or normal cells have seldom been studied. To address this problem, we studied the biological effects of L02 and HepG2 cells with ectogenous potassium ions. Cell proliferation, cell cycle, and apoptosis rate were analyzed. Our results indicated that potassium ions inhibited proliferation of L02 and HepG2 cells and promoted their apoptosis. Potassium ions induced apoptosis through regulating Bcl-2 family members and depolarized the mitochondrial membrane, especially for HepG2 cell. These biological effects were associated with channel protein HERG. By facilitating expression of channel protein HERG, potassium ions may prevent it from being shunted to procancerous pathways by inducing apoptosis. These results demonstrated that potassium ions may be a key regulator of liver cell function. Thus, our findings suggest that potassium ions could inhibit tumorigenesis through inducing apoptosis of hepatoma cells by upregulating potassium ions transport channel proteins HERG and VDAC1.

Cell sources for in vitro human liver cell culture models

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Freyer, Nora; Damm, Georg; Seehofer, Daniel; Knöspel, Fanny

2016-01-01

In vitro liver cell culture models are gaining increasing importance in pharmacological and toxicological research. The source of cells used is critical for the relevance and the predictive value of such models. Primary human hepatocytes (PHH) are currently considered to be the gold standard for hepatic in vitro culture models, since they directly reflect the specific metabolism and functionality of the human liver; however, the scarcity and difficult logistics of PHH have driven researchers to explore alternative cell sources, including liver cell lines and pluripotent stem cells. Liver cell lines generated from hepatomas or by genetic manipulation are widely used due to their good availability, but they are generally altered in certain metabolic functions. For the past few years, adult and pluripotent stem cells have been attracting increasing attention, due their ability to proliferate and to differentiate into hepatocyte-like cells in vitro. However, controlling the differentiation of these cells is still a challenge. This review gives an overview of the major human cell sources under investigation for in vitro liver cell culture models, including primary human liver cells, liver cell lines, and stem cells. The promises and challenges of different cell types are discussed with a focus on the complex 2D and 3D culture approaches under investigation for improving liver cell functionality in vitro. Finally, the specific application options of individual cell sources in pharmacological research or disease modeling are described. PMID:27385595

Preventive effect of halofuginone on concanavalin A-induced liver fibrosis.

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Jie Liang

Full Text Available Halofuginone (HF is an active component of extracts derived from the plant alkaloid febrifugine and has shown therapeutic promise in animal models of fibrotic disease. Our main objectives were to clarify the suppressive effect of HF on concanavalin A (ConA-induced liver fibrosis. ConA injection into the tail vein caused a great increase in the serum aspartate aminotransferase (AST and alanine aminotransferase (ALT levels, while orally administration of HF significantly decreased the levels of the transaminases. In addition, the levels of hyaluronic acid (HA, procollagen III (PCIII and TGF-β1 in the serum and collagen I, α-SMA, tissue inhibitors of metalloproteinase 2 (TIMP2 and Smad3 in the liver tissue were significantly lowered with the treatment of HF. Histological examination also demonstrated that HF significantly reduced the severity of liver fibrosis. Since ConA-induced liver fibrosis is caused by the repeated activation of T cells, immunomodulatory substances might be responsible for the suppressive effect of HF. We found that the production of nuclear factor (NF-kB in the serum was increased in ConA-treated group, while decreased significantly with the treatment of HF. The changes of inflammatory cytokines tumor necrosis factor (TNF-α, IL-6 and IL-1β in the serum followed the same rhythm. All together, our findings indicate that orally administration HF (10ppm would attenuate the liver fibrosis by suppressing the synthesis of collagen I and inflammation-mediated liver injury.

A new liver function test using the asialoglycoprotein-receptor system on the liver cell membrane, 2

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Kawa, Soukichi; Hazama, Hiroshi; Kojima, Michimasa

1986-01-01

We produced labeled neoglycoprotein (GHSA) that is physiologically equivalent to ASGP, and quantitatively examined whether its uptake by the liver is dose-related using the following methods: 1) binding assay between GHSA and ASGP receptors, 2) measurement of the liver extraction ratio in the initial circulation following administration into the portal vein, and 3) measurement of clearance in normal rats and rats with galacosamine-induced acute liver disorder. The binding assay showed a linear relationship between the concentration of 125 I-GHSA and the amount of ASGP receptors obtained from the rat liver. A membrane assay using 125 I-GHSA and the liver cell membrane revealed similar results. The liver extraction ratio in the initial circulation following the administration into the portal vein of normal rabbits was highly dose-dependent (r = -0.95 in the range of 5 - 100 μg GHSA). Serial imaging of 99m Tc-GHSA during two-hour period after administration into the peripheral blood showed specific accumulation in the liver beginning immediately after the intravenous injection and subsequent transport mainly via the biliary system into the small intestine in the normal rat and mainly into the urine in the bile duct ligated rat. As a dynamic model of 99m Tc-GHSA, its circulation through the heart and liver and inactivated release from the liver was used, and two-compartment analysis was made on measurement curves in the heart and liver to obtain clearance parameters. The concentration of administered 99m Tc-GHSA (50 - 100 μg/100 g body weight) showed a positive linear relationship with clearance. Administration of 50 μg/100 g body weight of 99m Tc-GHSA revealed a significant correlation (p < 0.001) between clearance and ASGP receptor activity in normal rats and rats with galactosamine-induced acute liver disorder. (J.P.N.)

Effects of Radiofrequency Induced local Hyperthermia on Normal Canine Liver

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Suh, Chang Ok; Loh, John J. K.; Seong, Jin Sil

1991-01-01

In order to assess the effects of radiofrequency-induced local hyperthermia on the normal liver, histopathologic findings and biochemical changes after localized hyperthermia in canine liver were studied. Hyperthermia was externally administered using the Thermotron RF-8 (Yamamoto Vinyter Co., Japan; Capacitive type heating machine) with parallel opposed electrodes. Thirteen dogs were used and allocated into one control group (N=3) and two treatment groups according to the treatment temperature. Group I (N=5) was heated with 42.5±0.5.deg.C for 30 minutes, and Group(N=5) was heated with 45±0.5.deg.C for 15-30 minutes. Samples of liver tissue were obtained through a needle biopsy immediately after hyperthermia and 7, 14 and 28 days after treatment and examined for SGOT, SGPT and alkaline phosphatase. Although SGOT and SGPT were elevated after hyperthermia in both groups (three of five in each group), there was no liver cell necrosis or hyperthermia related mortality in Group I. A hydropic swelling of hepatocytes was prominent histologic finding. Hyperthermia with 45.deg.C for 30 minutes was fatal and showed extensive liver cell necrosis. In conclusion, liver damage day heat of 42.5±0.5.deg.C for 30 minutes is reversible, and liver damage by heat of 45±0.5.deg.C for 30 minutes can be fatal or irreversible. However, these results cannot be applied directly to human trial. Therefore, in order to apply hyperthermic treatment on human liver tumor safely, close observation of temperature with proper thermometry is mandatory. Hyperthermic treatment should be confined to the tumor area while sparing a normal liver as much as possible

Decreased C-reactive protein induces abnormal vascular structure in a rat model of liver dysfunction induced by bile duct ligation

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Ji Hye Jun

2016-09-01

Full Text Available Background/Aims Chronic liver disease leads to liver fibrosis, and although the liver does have a certain regenerative capacity, this disease is associated with dysfunction of the liver vessels. C-reactive protein (CRP is produced in the liver and circulated from there for metabolism. CRP was recently shown to inhibit angiogenesis by inducing endothelial cell dysfunction. The objective of this study was to determine the effect of CRP levels on angiogenesis in a rat model of liver dysfunction induced by bile duct ligation (BDL. Methods The diameter of the hepatic vein was analyzed in rat liver tissues using hematoxylin and eosin (H&E staining. The expression levels of angiogenic factors, albumin, and CRP were analyzed by real-time PCR and Western blotting. A tube formation assay was performed to confirm the effect of CRP on angiogenesis in human umbilical vein endothelial cells (HUVECs treated with lithocholic acid (LCA and siRNA-CRP. Results The diameter of the hepatic portal vein increased significantly with the progression of cirrhosis. The expression levels of angiogenic factors were increased in the cirrhotic liver. In contrast, the expression levels of albumin and CRP were significantly lower in the liver tissue obtained from the BDL rat model than in the normal liver. The CRP level was correlated with the expression of albumin in hepatocytes treated with LCA and siRNA-CRP. Tube formation was significantly decreased in HUVECs when they were treated with LCA or a combination of LCA and siRNA-CRP. Conclusion CRP seems to be involved in the abnormal formation of vessels in hepatic disease, and so it could be a useful diagnostic marker for hepatic disease.

Decreased C-reactive protein induces abnormal vascular structure in a rat model of liver dysfunction induced by bile duct ligation.

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Jun, Ji Hye; Choi, Jong Ho; Bae, Si Hyun; Oh, Seh Hoon; Kim, Gi Jin

2016-09-01

Chronic liver disease leads to liver fibrosis, and although the liver does have a certain regenerative capacity, this disease is associated with dysfunction of the liver vessels. C-reactive protein (CRP) is produced in the liver and circulated from there for metabolism. CRP was recently shown to inhibit angiogenesis by inducing endothelial cell dysfunction. The objective of this study was to determine the effect of CRP levels on angiogenesis in a rat model of liver dysfunction induced by bile duct ligation (BDL). The diameter of the hepatic vein was analyzed in rat liver tissues using hematoxylin and eosin (H&E) staining. The expression levels of angiogenic factors, albumin, and CRP were analyzed by real-time PCR and Western blotting. A tube formation assay was performed to confirm the effect of CRP on angiogenesis in human umbilical vein endothelial cells (HUVECs) treated with lithocholic acid (LCA) and siRNA-CRP. The diameter of the hepatic portal vein increased significantly with the progression of cirrhosis. The expression levels of angiogenic factors were increased in the cirrhotic liver. In contrast, the expression levels of albumin and CRP were significantly lower in the liver tissue obtained from the BDL rat model than in the normal liver. The CRP level was correlated with the expression of albumin in hepatocytes treated with LCA and siRNA-CRP. Tube formation was significantly decreased in HUVECs when they were treated with LCA or a combination of LCA and siRNA-CRP. CRP seems to be involved in the abnormal formation of vessels in hepatic disease, and so it could be a useful diagnostic marker for hepatic disease.

Silent information regulator 1 (SIRT1) ameliorates liver fibrosis via promoting activated stellate cell apoptosis and reversion

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Wu, Yuting, E-mail: wuyuting1302@sina.com; Liu, Xuejiao; Zhou, Qun; Huang, Cheng; Meng, Xiaoming; Xu, Fengyun; Li, Jun, E-mail: lj@ahmu.edu.cn

2015-12-01

SIRT1 (silent information regulator 1), a conserved NAD +-dependent histone deacetylase, is closely related with various biological processes. Moreover, the important role of SIRT1 in alcoholic liver disease, nonalcoholic fatty liver and HCC had been widely reported. Recently, a novel role of SIRT1 was uncovered in organ fibrosis diseases. Here, we investigated the inhibitory effect of SIRT1 in liver fibrogenesis. SIRT1 protein was dramatically decreased in CCl4-treated mice livers. Stimulation of LX-2 cells with TGF-β1 also resulted in a significant suppression of SIRT1 protein. Nevertheless, TGF-β1-induced LX-2 cell activation was inhibited by SIRT1 plasmid, and this was accompanied by up-regulation of cell apoptosis-related proteins. Overexpression of SIRT1 also attenuated TGF-β1-induced expression of myofibroblast markers α-SMA and COL1a. However, the important characteristic of the recovery of liver fibrosis is not only the apoptosis of activated stellate cells but also the reversal of the myofibroblast-like phenotype to a quiescent-like phenotype. Restoration of SIRT1 protein was observed in the in vivo spontaneously liver fibrosis reversion model and in vitro MDI (isobutylmethylxanthine, dexamethasone, and insulin)-induced reversed stellate cells, and forced expression of SIRT1 also promoted the reversal of activated stellate cells. Furthermore, lncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) was increased in liver fibrosis. RNAi-mediated suppression of MALAT1 resulted in a decrease of myofibroblast markers and restoration of SIRT1 protein. These observations suggested that SIRT1 contributed to apoptosis and reversion of activated LX-2 cells and SIRT1 might be regulated by MALAT1 in liver fibrosis. Therefore, SIRT1 could be considered as a valuable therapeutic target for translational studies of liver fibrosis. - Highlights: • This is the first report of SIRT1 expression and function in liver fibrogenesis and reversion. �

The C/EBPbeta isoform, liver-inhibitory protein (LIP), induces autophagy in breast cancer cell lines

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Abreu, Maria M.; Sealy, Linda

2010-01-01

Autophagy is a process involving the bulk degradation of cellular components in the cytoplasm via the lysosomal degradation pathway. Autophagy manifests a protective role in stressful conditions such as nutrient or growth factor depletion; however, extensive degradation of regulatory molecules or organelles essential for survival can lead to the demise of the cell, or autophagy-mediated cell death. The role of autophagy in cancer is complex with roles in both tumor suppression and tumor promotion proposed. Here we report that an isoform of the C/EBPbeta transcription factor, liver-enriched inhibitory protein (LIP), induces cell death in human breast cancer cells and stimulates autophagy. Overexpression of LIP is incompatible with cell growth and when cell cycle analysis was performed, a DNA profile of cells undergoing apoptosis was not observed. Instead, LIP expressing cells appeared to have large autophagic vesicles when examined via electron microscopy. Autophagy was further assessed in LIP expressing cells by monitoring the development of acidic vesicular organelles and conversion of LC3 from the cytoplasmic form to the membrane-bound form. Our work shows that C/EBPbeta isoform, LIP, is another member of the group of transcription factors, including E2F1 and p53, which are capable of playing a role in autophagy.

The C/EBPbeta isoform, liver-inhibitory protein (LIP), induces autophagy in breast cancer cell lines

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Abreu, Maria M. [Department of Cancer Biology, 752 Preston Research Building, Vanderbilt University, Nashville, TN 37232 (United States); Sealy, Linda, E-mail: Linda.sealy@vanderbilt.edu [Department of Cancer Biology, 752 Preston Research Building, Vanderbilt University, Nashville, TN 37232 (United States); Department of Molecular Physiology and Biophysics, 752 Preston Research Building, Vanderbilt University, Nashville, TN 37232 (United States)

2010-11-15

Autophagy is a process involving the bulk degradation of cellular components in the cytoplasm via the lysosomal degradation pathway. Autophagy manifests a protective role in stressful conditions such as nutrient or growth factor depletion; however, extensive degradation of regulatory molecules or organelles essential for survival can lead to the demise of the cell, or autophagy-mediated cell death. The role of autophagy in cancer is complex with roles in both tumor suppression and tumor promotion proposed. Here we report that an isoform of the C/EBPbeta transcription factor, liver-enriched inhibitory protein (LIP), induces cell death in human breast cancer cells and stimulates autophagy. Overexpression of LIP is incompatible with cell growth and when cell cycle analysis was performed, a DNA profile of cells undergoing apoptosis was not observed. Instead, LIP expressing cells appeared to have large autophagic vesicles when examined via electron microscopy. Autophagy was further assessed in LIP expressing cells by monitoring the development of acidic vesicular organelles and conversion of LC3 from the cytoplasmic form to the membrane-bound form. Our work shows that C/EBPbeta isoform, LIP, is another member of the group of transcription factors, including E2F1 and p53, which are capable of playing a role in autophagy.

Disease modeling using human induced pluripotent stem cells: lessons from the liver.

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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. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Drug-induced liver injury due to antibiotics.

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Björnsson, Einar S

Drug-induced liver injury (DILI) is an important differential diagnosis in patients with abnormal liver tests and normal hepatobiliary imaging. Of all known liver diseases, the diagnosis of DILI is probably one of the most difficult one to be established. In all major studies on DILI, antibiotics are the most common type of drugs that have been reported. The clinical phenotype of different types of antibiotics associated with liver injury is highly variable. Some widely used antibiotics such as amoxicillin-clavulanate have been shown to have a delayed onset on liver injury and recently cefazolin has been found to lead to liver injury 1-3 weeks after exposure of a single infusion. The other extreme is the nature of nitrofurantoin-induced liver injury, which can occur after a few years of treatment and lead to acute liver failure (ALF) or autoimmune-like reaction. Most patients with liver injury associated with use of antibiotics have a favorable prognosis. However, patients with jaundice have approximately 10% risk of death from liver failure and/or require liver transplantation. In rare instances, the hepatoxicity can lead to chronic injury and vanishing bile duct syndrome. Given, sometimes very severe consequences of the adverse liver reactions, it cannot be over emphasized that the indication for the different antibiotics should be evidence-based and symptoms and signs of liver injury from the drugs should lead to prompt cessation of therapy.

Magnetic targeting of iron-oxide-labeled fluorescent hepatoma cells to the liver

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Luciani, Alain [Universite Rene Descartes, Hopital Europeen Georges Pompidou, Laboratoire de Recherche en Imagerie, EA 4062, Paris (France); Imagerie Medicale, Faculte de Medecine Paris XII, CHU Henri Mondor, Creteil cedex (France); Wilhelm, Claire; Gazeau, Florence [Universite Paris Diderot, Batiment Condorcet, Laboratoire Matiere et Systemes Complexes, CNRS-UMR 7057, Paris Cedex (France); Bruneval, Patrick [Anatomopathologie, Hopital Europeen Georges Pompidou, Paris (France); Cunin, Patrick [Unite de Recherche Clinique, Faculte de Medecine Paris XII, CHU Henri Mondor, Creteil cedex (France); Autret, Gwennhael; Clement, Olivier [Universite Rene Descartes, Hopital Europeen Georges Pompidou, Laboratoire de Recherche en Imagerie, EA 4062, Paris (France); Rahmouni, Alain [Imagerie Medicale, Faculte de Medecine Paris XII, CHU Henri Mondor, Creteil cedex (France)

2009-05-15

The purpose of this study was to determine whether an external magnet field can induce preferential trafficking of magnetically labeled Huh7 hepatoma cells to the liver following liver cell transplantation. Huh7 hepatoma cells were labeled with anionic magnetic nanoparticles (AMNP) and tagged with a fluorescent membrane marker (PKH67). Iron-uptake was measured by magnetophoresis. Twenty C57Bl6 mice received an intrasplenic injection of 2 x 10{sup 6} labeled cells. An external magnet (0.29 T; 25 T/m) was placed over the liver of 13 randomly selected animals (magnet group), while the remaining 7 animals served as controls. MRI (1.5 T) and confocal fluorescence microscopy (CFM) were performed 10 days post-transplantation. The presence and location of labeled cells within the livers were compared in the magnet group and controls, and confronted with histological analysis representing the standard of reference. Mean iron content per cell was 6 pg. Based on histology, labeled cells were more frequently present within recipient livers in the magnet group (p < 0.01) where their distribution was preferentially peri-vascular (p<0.05). MRI and CFM gave similar results for the overall detection of transplanted cells (kappa=0.828) and for the identification of peri-vascular cells (kappa=0.78). Application of an external magnet can modify the trafficking of transplanted cells, especially by promoting the formation of perivascular aggregates. (orig.)

Vildagliptin Can Alleviate Endoplasmic Reticulum Stress in the Liver Induced by a High Fat Diet

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Xiaoqing Ma

2018-01-01

Full Text Available Purpose. We investigated whether a DDP-4 inhibitor, vildagliptin, alleviated ER stress induced by a high fat diet and improved hepatic lipid deposition. Methods. C57BL/6 mice received standard chow diet (CD, high fat diet (HFD, and HFD administered with vildagliptin (50 mg/Kg (V-HFD. After administration for 12 weeks, serum alanine aminotransferase, glucose, cholesterol, triglyceride, and insulin levels were analyzed. Samples of liver underwent histological examination and transmission electron microscopy, real-time PCR for gene expression levels, and western blots for protein expression levels. ER stress was induced in HepG2 cells with palmitic acid and the effects of vildagliptin were investigated. Results. HFD mice showed increased liver weight/body weight (20.27% and liver triglycerides (314.75% compared to CD mice, but these decreased by 9.27% and 21.83%, respectively, in V-HFD mice. In the liver, HFD induced the expression of ER stress indicators significantly, which were obviously decreased by vildagliptin. In vitro, the expressions of molecular indicators of ER stress were reduced in HepG2 when vildagliptin was administered. Conclusions. Vildagliptin alleviates hepatic ER stress in a mouse high fat diet model. In HepG2 cells, vildagliptin directly reduced ER stress. Therefore, vildagliptin may be a potential agent for nonalcoholic fatty liver disease.

Estradiol inhibits hepatic stellate cell area and collagen synthesis in the chicken liver.

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Nishimura, Shotaro; Teshima, Akifumi; Kawabata, Fuminori; Tabata, Shoji

2017-11-01

Hepatic stellate cells (HSCs) are the main collagen-producing cells in the liver. The HSC area and amount of collagen fibers are different between male and female chickens. This study was performed to confirm the effect of estradiol on collagen synthesis in the growing chicken liver. Blood estradiol levels in chicks were compared at 4 and 8 weeks of age, and the collagen fibril network in liver tissue was observed at 8 weeks by scanning electron microscopy. Intraperitoneal administrations of estradiol and tamoxifen to male and female chicks, respectively, were performed daily from 5 to 8 weeks of age. The areas of HSCs and collagen contents were measured in the liver tissue. The blood estradiol level was higher in females than in males, and the collagen fibril network was denser in males than in females at 8 weeks of age. Estradiol administration in males induced decreases in the HSC area and collagen content of the liver. Conversely, tamoxifen administration in females induced an increase in the HSC area but did not facilitate collagen synthesis. Based on these results, estradiol inhibits the area and collagen synthesis of HSCs in the growing chicken liver under normal physiological conditions. © 2017 Japanese Society of Animal Science.

Kupffer cells hasten resolution of liver immunopathology in mouse models of viral hepatitis.

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Giovanni Sitia

2011-06-01

Full Text Available Kupffer cells (KCs are widely considered important contributors to liver injury during viral hepatitis due to their pro-inflammatory activity. Herein we utilized hepatitis B virus (HBV-replication competent transgenic mice and wild-type mice infected with a hepatotropic adenovirus to demonstrate that KCs do not directly induce hepatocellular injury nor do they affect the pathogenic potential of virus-specific CD8 T cells. Instead, KCs limit the severity of liver immunopathology. Mechanistically, our results are most compatible with the hypothesis that KCs contain liver immunopathology by removing apoptotic hepatocytes in a manner largely dependent on scavenger receptors. Apoptotic hepatocytes not readily removed by KCs become secondarily necrotic and release high-mobility group box 1 (HMGB-1 protein, promoting organ infiltration by inflammatory cells, particularly neutrophils. Overall, these results indicate that KCs resolve rather than worsen liver immunopathology.

Induction of Inducible Nitric Oxide Synthase by Lipopolysaccharide and the Influences of Cell Volume Changes, Stress Hormones and Oxidative Stress on Nitric Oxide Efflux from the Perfused Liver of Air-Breathing Catfish, Heteropneustes fossilis.

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Mahua G Choudhury

Full Text Available The air-breathing singhi catfish (Heteropneustes fossilis is frequently being challenged by bacterial contaminants, and different environmental insults like osmotic, hyper-ammonia, dehydration and oxidative stresses in its natural habitats throughout the year. The main objectives of the present investigation were to determine (a the possible induction of inducible nitric oxide synthase (iNOS gene with enhanced production of nitric oxide (NO by intra-peritoneal injection of lipopolysaccharide (LPS (a bacterial endotoxin, and (b to determine the effects of hepatic cell volume changes due to anisotonicity or by infusion of certain metabolites, stress hormones and by induction of oxidative stress on production of NO from the iNOS-induced perfused liver of singhi catfish. Intra-peritoneal injection of LPS led to induction of iNOS gene and localized tissue specific expression of iNOS enzyme with more production and accumulation of NO in different tissues of singhi catfish. Further, changes of hydration status/cell volume, caused either by anisotonicity or by infusion of certain metabolites such as glutamine plus glycine and adenosine, affected the NO production from the perfused liver of iNOS-induced singhi catfish. In general, increase of hydration status/cell swelling due to hypotonicity caused decrease, and decrease of hydration status/cell shrinkage due to hypertonicity caused increase of NO efflux from the perfused liver, thus suggesting that changes in hydration status/cell volume of hepatic cells serve as a potent modulator for regulating the NO production. Significant increase of NO efflux from the perfused liver was also observed while infusing the liver with stress hormones like epinephrine and norepinephrine, accompanied with decrease of hydration status/cell volume of hepatic cells. Further, oxidative stress, caused due to infusion of t-butyl hydroperoxide and hydrogen peroxide separately, in the perfused liver of singhi catfish, resulted

Dysregulated Intrahepatic CD4+ T-Cell Activation Drives Liver Inflammation in Ileitis-Prone SAMP1/YitFc MiceSummary

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Sara Omenetti

2015-07-01

Full Text Available Background & Aims: Liver inflammation is a common extraintestinal manifestation of inflammatory bowel disease (IBD, but whether liver involvement is a consequence of a primary intestinal defect or results from alternative pathogenic processes remains unclear. Therefore, we sought to determine the potential pathogenic mechanism(s of concomitant liver inflammation in an established murine model of IBD. Methods: Liver inflammation and immune cell subsets were characterized in ileitis-prone SAMP1/YitFc (SAMP and AKR/J (AKR control mice, lymphocyte-depleted SAMP (SAMPxRag-1−/−, and immunodeficient SCID recipient mice receiving SAMP or AKR donor CD4+ T cells. Proliferation and suppressive capacity of CD4+ T-effector (Teff and T-regulatory (Treg cells from gut-associated lymphoid tissue (GALT and livers of SAMP and AKR mice were measured. Results: Surprisingly, prominent inflammation was detected in 4-week-old SAMP livers before histologic evidence of ileitis, whereas both disease phenotypes were absent in age-matched AKR mice. SAMP liver disease was characterized by abundant infiltration of lymphocytes, required for hepatic inflammation to occur, a TH1-skewed environment, and phenotypically activated CD4+ T cells. SAMP intrahepatic CD4+ T cells also had the ability to induce liver and ileal inflammation when adoptively transferred into SCID recipients, whereas GALT-derived CD4+ T cells produced milder ileitis but not liver inflammation. Interestingly, SAMP intrahepatic CD4+ Teff cells showed increased proliferation compared with both SAMP GALT- and AKR liver-derived CD4+ Teff cells, and SAMP intrahepatic Tregs were decreased among CD4+ T cells and impaired in in vitro suppressive function compared with AKR. Conclusions: Activated intrahepatic CD4+ T cells induce liver inflammation and contribute to experimental ileitis via locally impaired hepatic immunosuppressive function. Keywords: Hepatic CD4+ T Cells, IBD-Associated Liver

Traditional Chinese Medicine and Herb-induced Liver Injury: Comparison with Drug-induced Liver Injury.

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Jing, Jing; Teschke, Rolf

2018-03-28

Cases of suspected herb-induced liver injury (HILI) caused by herbal Traditional Chinese Medicines (TCMs) and of drug-induced liver injury (DILI) are commonly published in the scientific literature worldwide. As opposed to the multiplicity of botanical chemicals in herbal TCM products, which are often mixtures of several herbs, conventional Western drugs contain only a single synthetic chemical. It is therefore of interest to study how HILI by TCM and DILI compare with each other, and to what extent results from each liver injury type can be transferred to the other. China is among the few countries with a large population using synthetic Western drugs as well as herbal TCM. Therefore, China is well suited to studies of liver injury comparing drugs with TCM herbs. Despite some concordance, recent analyses of liver injury cases with verified causality, using the Roussel Uclaf Causality Assessment Method, revealed major differences in HILI caused by TCMs as compared to DILI with respect to the following features: HILI cases are less frequently observed as compared to DILI, have a smaller proportion of females and less unintentional rechallenge events, and present a higher rate of hepatocellular injury features. Since many results were obtained among Chinese residents who had access to and had used Western drugs and TCM herbs, such ethnic homogeneity supports the contention that the observed differences of HILI and DILI in the assessed population are well founded.

Manipulation of the Host Cell Membrane during Plasmodium Liver Stage Egress

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Paul-Christian Burda

2017-04-01

Full Text Available A crucial step in the life cycle of Plasmodium parasites is the transition from the liver stage to the blood stage. Hepatocyte-derived merozoites reach the blood vessels of the liver inside host cell-derived vesicles called merosomes. The molecular basis of merosome formation is only partially understood. Here we show that Plasmodium berghei liver stage merozoites, upon rupture of the parasitophorous vacuole membrane, destabilize the host cell membrane (HCM and induce separation of the host cell actin cytoskeleton from the HCM. At the same time, the phospholipid and protein composition of the HCM appears to be substantially altered. This includes the loss of a phosphatidylinositol 4,5-bisphosphate (PIP2 reporter and the PIP2-dependent actin-plasma membrane linker ezrin from the HCM. Furthermore, transmembrane domain-containing proteins and palmitoylated and myristoylated proteins, as well as glycosylphosphatidylinositol-anchored proteins, lose their HCM localization. Collectively, these findings provide an explanation of HCM destabilization during Plasmodium liver stage egress and thereby contribute to our understanding of the molecular mechanisms that lead to merosome formation.

Induction of insulin secretion in engineered liver cells by nitric oxide

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Özcan Sabire

2007-10-01

Full Text Available Abstract Background Type 1 Diabetes Mellitus results from an autoimmune destruction of the pancreatic beta cells, which produce insulin. The lack of insulin leads to chronic hyperglycemia and secondary complications, such as cardiovascular disease. The currently approved clinical treatments for diabetes mellitus often fail to achieve sustained and optimal glycemic control. Therefore, there is a great interest in the development of surrogate beta cells as a treatment for type 1 diabetes. Normally, pancreatic beta cells produce and secrete insulin only in response to increased blood glucose levels. However in many cases, insulin secretion from non-beta cells engineered to produce insulin occurs in a glucose-independent manner. In the present study we engineered liver cells to produce and secrete insulin and insulin secretion can be stimulated via the nitric oxide pathway. Results Expression of either human insulin or the beta cell specific transcription factors PDX-1, NeuroD1 and MafA in the Hepa1-6 cell line or primary liver cells via adenoviral gene transfer, results in production and secretion of insulin. Although, the secretion of insulin is not significantly increased in response to high glucose, treatment of these engineered liver cells with L-arginine stimulates insulin secretion up to three-fold. This L-arginine-mediated insulin release is dependent on the production of nitric oxide. Conclusion Liver cells can be engineered to produce insulin and insulin secretion can be induced by treatment with L-arginine via the production of nitric oxide.

Correlation between Antistress and Hepatoprotective Effects of Schisandra Lignans Was Related with Its Antioxidative Actions in Liver Cells

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Hao-Jie Pu

2012-01-01

Full Text Available The present study was conducted to investigate the relationship between the anti-stress and hepato-protective effects of Schisandra Lignans Extract (SLE on stress-induced liver damage. Seven weeks old male mice were fixed in a restraint tube for 18 h to induce liver damage. SLE was orally administered to animals for 5 days at dosages of 100 and 200 mg/kg/day before exposed to restraint stress. Oral administration of SLE significantly reduced restraint-induced liver damage in experimental animal. SLE was further found to significantly alleviate the provocation of corticosterone in stressed mice. SLE also significantly decreased oxidative damage and increased anti-oxidative capability of liver cells by preventing the over production and accumulation of free radicals. In conclusion, the protective effects of SLE on stress-induced liver damage were confirmed, and the correlation between hepatoprotective and anti-stress effects of schisandra lignans was possible related to its alleviation on the malignant effects of stressors for bio-homeostasis, such as balance of oxidation and reduction in cells.

Edaravone protects endotoxin-induced liver injury by inhibiting apoptosis and reducing proinflammatory cytokines.

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Zong, L; Yu, Q H; Du, Y X; Deng, X M

2014-02-01

Studies have shown that edaravone may prevent liver injury. This study aimed to investigate the effects of edaravone on the liver injury induced by D-galactosamine (GalN) and lipopolysaccharide (LPS) in female BALB/c mice. Edaravone was injected into mice 30 min before and 4 h after GalN/LPS injection. The survival rate was determined within the first 24 h. Animals were killed 8 h after GalN/LPS injection, and liver injury was biochemically and histologically assessed. Hepatocyte apoptosis was measured by TUNEL staining; proinflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)] in the liver were assayed by ELISA; expression of caspase-8 and caspase-3 proteins was detected by Western blot assay; and caspase-3 activity was also determined. Results showed that GalN/LPS induced marked elevations in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Edaravone significantly inhibited elevation of serum AST and ALT, accompanied by an improvement in histological findings. Edaravone lowered the levels of TNF-α and IL-6 and reduced the number of TUNEL-positive cells. In addition, 24 h after edaravone treatment, caspase-3 activity and mortality were reduced. Edaravone may effectively ameliorate GalN/LPS-induced liver injury in mice by reducing proinflammatory cytokines and inhibiting apoptosis.

Edaravone protects endotoxin-induced liver injury by inhibiting apoptosis and reducing proinflammatory cytokines

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Zong, L. [Second Military Medical University, Changhai Hospital, Department of Anesthesiology, Shanghai, China, Department of Anesthesiology, Changhai Hospital, Second Military Medical University, Shanghai (China); No. 82 Hospital of People' s Liberation Army, Department of Anesthesiology, Jiangsu, China, Department of Anesthesiology, No. 82 Hospital of People' s Liberation Army, Jiangsu (China); Yu, Q. H. [Second Military Medical University, Changhai Hospital, Department of Gastroenterology, Shanghai, China, Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai (China); Du, Y. X. [No. 82 Hospital of People' s Liberation Army, Department of Anesthesiology, Jiangsu, China, Department of Anesthesiology, No. 82 Hospital of People' s Liberation Army, Jiangsu (China); Deng, X. M. [Second Military Medical University, Changhai Hospital, Department of Anesthesiology, Shanghai, China, Department of Anesthesiology, Changhai Hospital, Second Military Medical University, Shanghai (China)

2014-03-03

Studies have shown that edaravone may prevent liver injury. This study aimed to investigate the effects of edaravone on the liver injury induced by D-galactosamine (GalN) and lipopolysaccharide (LPS) in female BALB/c mice. Edaravone was injected into mice 30 min before and 4 h after GalN/LPS injection. The survival rate was determined within the first 24 h. Animals were killed 8 h after GalN/LPS injection, and liver injury was biochemically and histologically assessed. Hepatocyte apoptosis was measured by TUNEL staining; proinflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)] in the liver were assayed by ELISA; expression of caspase-8 and caspase-3 proteins was detected by Western blot assay; and caspase-3 activity was also determined. Results showed that GalN/LPS induced marked elevations in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Edaravone significantly inhibited elevation of serum AST and ALT, accompanied by an improvement in histological findings. Edaravone lowered the levels of TNF-α and IL-6 and reduced the number of TUNEL-positive cells. In addition, 24 h after edaravone treatment, caspase-3 activity and mortality were reduced. Edaravone may effectively ameliorate GalN/LPS-induced liver injury in mice by reducing proinflammatory cytokines and inhibiting apoptosis.

Edaravone protects endotoxin-induced liver injury by inhibiting apoptosis and reducing proinflammatory cytokines

International Nuclear Information System (INIS)

Zong, L.; Yu, Q.H.; Du, Y.X.; Deng, X.M.

2014-01-01

Studies have shown that edaravone may prevent liver injury. This study aimed to investigate the effects of edaravone on the liver injury induced by D-galactosamine (GalN) and lipopolysaccharide (LPS) in female BALB/c mice. Edaravone was injected into mice 30 min before and 4 h after GalN/LPS injection. The survival rate was determined within the first 24 h. Animals were killed 8 h after GalN/LPS injection, and liver injury was biochemically and histologically assessed. Hepatocyte apoptosis was measured by TUNEL staining; proinflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)] in the liver were assayed by ELISA; expression of caspase-8 and caspase-3 proteins was detected by Western blot assay; and caspase-3 activity was also determined. Results showed that GalN/LPS induced marked elevations in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Edaravone significantly inhibited elevation of serum AST and ALT, accompanied by an improvement in histological findings. Edaravone lowered the levels of TNF-α and IL-6 and reduced the number of TUNEL-positive cells. In addition, 24 h after edaravone treatment, caspase-3 activity and mortality were reduced. Edaravone may effectively ameliorate GalN/LPS-induced liver injury in mice by reducing proinflammatory cytokines and inhibiting apoptosis

Induction and maintenance of protective CD8+ T cells against malaria liver stages: implications for vaccine development

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Sze-Wah Tse

2011-08-01

Full Text Available CD8+ T cells against malaria liver stages represent a major protective immune mechanism against infection. Following induction in the peripheral lymph nodes by dendritic cells (DCs, these CD8+ T cells migrate to the liver and eliminate parasite infected hepatocytes. The processing and presentation of sporozoite antigen requires TAP mediated transport of major histocompatibility complex class I epitopes to the endoplasmic reticulum. Importantly, in DCs this process is also dependent on endosome-mediated cross presentation while this mechanism is not required for epitope presentation on hepatocytes. Protective CD8+ T cell responses are strongly dependent on the presence of CD4+ T cells and the capacity of sporozoite antigen to persist for a prolonged period of time. While human trials with subunit vaccines capable of inducing antibodies and CD4+ T cell responses have yielded encouraging results, an effective anti-malaria vaccine will likely require vaccine constructs designed to induce protective CD8+ T cells against malaria liver stages.

Fetal liver stromal cells promote hematopoietic cell expansion

International Nuclear Information System (INIS)

Zhou, Kun; Hu, Caihong; Zhou, Zhigang; Huang, Lifang; Liu, Wenli; Sun, Hanying

2009-01-01

Future application of hematopoietic stem and progenitor cells (HSPCs) in clinical therapies largely depends on their successful expansion in vitro. Fetal liver (FL) is a unique hematopoietic organ in which hematopoietic cells markedly expand in number, but the mechanisms involved remain unclear. Stromal cells (StroCs) have been suggested to provide a suitable cellular environment for in vitro expansion of HSPCs. In this study, murine StroCs derived from FL at E14.5, with a high level of Sonic hedgehog (Shh) and Wnt expression, were found to have an increased ability to support the proliferation of HSPCs. This effect was inhibited by blocking Shh signaling. Supplementation with soluble Shh-N promoted the proliferation of hematopoietic cells by activating Wnt signaling. Our findings suggest that FL-derived StroCs support proliferation of HSPCs via Shh inducing an autocrine Wnt signaling loop. The use of FL-derived StroCs and regulation of the Shh pathway might further enhance HPSC expansion.

Hydrogen peroxide impairs autophagic flux in a cell model of nonalcoholic fatty liver disease

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Jiang, Pengtao [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101 (China); University of Chinese Academy of Sciences, 19 Yuquan Road, Shijingshan District, Beijing 100049 (China); Huang, Zhen [Department of Abdominal Surgical Oncology, Cancer Hospital, Chinese Academy of Medical Sciences, 17 Panjiayuan Nanli, Chaoyang District, Beijing 100021 (China); Zhao, Hong, E-mail: zhaohong9@sina.com [Department of Abdominal Surgical Oncology, Cancer Hospital, Chinese Academy of Medical Sciences, 17 Panjiayuan Nanli, Chaoyang District, Beijing 100021 (China); Wei, Taotao, E-mail: weitt@moon.ibp.ac.cn [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101 (China)

2013-04-19

Highlights: •Free fatty acids exposure induces elevated autophagy. •H{sub 2}O{sub 2} inhibits autophagic flux through impairing the fusion between autophagosomes and lysosomes. •Inhibition of autophagy potentiates H{sub 2}O{sub 2}-induced cell death. -- Abstract: Nonalcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver disease, but the pathogenesis of NAFLD is not fully clear. The aim of this study was to determine whether autophagy plays a role in the pathogenesis of NAFLD. We found that the levels of autophagy were elevated in hepatoma cells upon exposure to free fatty acids, as confirmed by the increase in the number of autophagosomes. However, exposure of hepatoma cells to H{sub 2}O{sub 2} and TNF-α, two typical “second hit” factors, increased the initiation of autophagy but inhibited the autophagic flux. The inhibition of autophagy sensitized cells to pro-apoptotic stimuli. Taken together, our results suggest that autophagy acts as a protective mechanism in the pathogenesis of NAFLD and that impairment of autophagy might induce more severe lesions of the liver. These findings will be a benefit to the understanding of the pathogenesis of NAFLD and might suggest a strategy for the prevention and cure of NAFLD.

Steatosis induced CCL5 contributes to early-stage liver fibrosis in nonalcoholic fatty liver disease progress.

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Li, Bing-Hang; He, Fang-Ping; Yang, Xin; Chen, Yuan-Wen; Fan, Jian-Gao

2017-02-01

The rapidly increasing prevalence of nonalcoholic fatty liver disease (NAFLD) has become one of the major public health threats in China and worldwide. However, during the development of NAFLD, the key mechanism underlying the progression of related fibrosis remains unclear, which greatly impedes the development of optimal NAFLD therapy. In the current study, we were endeavored to characterize a proinflammatory cytokine, CCL5, as a major contributor for fibrosis in NAFLD. The results showed that CCL5 was highly expressed in fatty liver and NASH patients. In NAFLD rats induced by 8-week-HFD, CCL5 and its receptor, CCR5, were significantly up-regulated and liver fibrosis exclusively occurred in this group. In addition, we showed that hepatocytes are the major source contributing to this CCL5 elevation. Interestingly, a CCL5 inhibitor Met-CCL5, significantly decreased liver fibrosis but not hepatic steatosis. Using a cell model of hepatic steatosis, we found that the conditioned medium of lipid-overloaded hepatocytes (Fa2N-4 cells) which produced excessive CCL5 stimulated the profibrotic activities of hepatic stellate cells (LX-2) as manifested by increased migration rate, proliferation and collagen production of LX-2 cells. CCL5 knockdown in Fa2N-4 cells, Met-CCL5 or CCR5 antibody treatment on LX-2 cells all significantly inhibited the conditioned medium of FFA-treated Fa2N-4 cells to exert stimulatory effects on LX-2 cells. Consistently, the conditioned medium of Fa2N-4 cells with CCL5 over-expression significantly enhanced migration rate, cell proliferation and collagen production of LX-2 cells. All these results support that CCL5 produced by steatotic hepatocytes plays an essential role in fibrotic signaling machinery of NAFLD. In addition, we were able to identify C/EBP-β as the up-stream regulator of CCL5 gene transcription in hepatocytes treated with free fatty acid (FFA). Our data strongly supported that CCL5 plays a pivotal regulatory role in

Role of stellate cells in alcoholic liver fibrosis

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Krzysztof Plewka

2009-07-01

Full Text Available Many different diseases and toxins can cause liver damage, which is diffi cult to treat and often leads to the development of liver fi brosis or even cirrhosis. The key event in this process is the activation of hepatic stellate cells (HSCs. During such activation, HSCs undergo a dramatic transformation in morphology and behavior, changing from a neuronal-like to a fi broblast-like morphology. After activation, HSCs increase their proliferation rate and extracellular matrix (ECM production. Overproduction of ECM, which contains mainly collagen type I, is a direct cause of liver disruption. HSCs also produce substances which inhibit protease activities, such as TIMPs, which enhance ECM deposition in the liver. On the molecular level, HSCs are activated by cytokines, growth factors, and oxidative stress, which are abundant in affl icted liver. These factors induce intracellular signals transmitted by many kinases, the most important of which are JNK, ERK1/2, p38, TAK-1, PKC, FAK, and P3IK. Signals transmitted via these pathways change the activities of transcription factors such as Smad, AP-1, and NF-κβ. This in turn causes changes In gene transcription and ultimately alters the whole cell’s behavior and morphology. The cell begins the production collagen type I, TIMP-1, and aSMA. Activated HSCs can sustain their own activation by producing growth factors such as PDGF and TGF-β. Despite the vast knowledge about the mechanisms causing liver fi brosis and cirrhosis, there is still no effective cure. Further studies are therefore needed to solve this problem.

Ozagrel hydrochloride, a selective thromboxane A2 synthase inhibitor, alleviates liver injury induced by acetaminophen overdose in mice

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Tomishima Yoshiro

2013-01-01

Full Text Available Abstract Background Overdosed acetaminophen (paracetamol, N-acetyl-p-aminophenol; APAP causes severe liver injury. We examined the effects of ozagrel, a selective thromboxane A2 (TXA2 synthase inhibitor, on liver injury induced by APAP overdose in mice. Methods Hepatotoxicity was induced to ICR male mice by an intraperitoneal injection with APAP (330 mg/kg. The effects of ozagrel (200 mg/kg treatment 30 min after the APAP injection were evaluated with mortality, serum alanine aminotransferase (ALT levels and hepatic changes, including histopathology, DNA fragmentation, mRNA expression and total glutathione contents. The impact of ozagrel (0.001-1 mg/mL on cytochrome P450 2E1 (CYP2E1 activity in mouse hepatic microsome was examined. RLC-16 cells, a rat hepatocytes cell line, were exposed to 0.25 mM N-acetyl-p-benzoquinone imine (NAPQI, a hepatotoxic metabolite of APAP. In this model, the cytoprotective effects of ozagrel (1–100 muM were evaluated by the WST-1 cell viability assay. Results Ozagel treatment significantly attenuated higher mortality, elevated serum alanine aminotransferase levels, excessive hepatic centrilobular necrosis, hemorrhaging and DNA fragmentation, as well as increase in plasma 2,3-dinor thromboxane B2 levels induced by APAP injection. Ozagrel also inhibited the hepatic expression of cell death-related mRNAs induced by APAP, such as jun oncogene, FBJ osteosarcoma oncogene (fos and C/EBP homologous protein (chop, but did not suppress B-cell lymphoma 2-like protein11 (bim expression and hepatic total glutathione depletion. These results show ozagrel can inhibit not all hepatic changes but can reduce the hepatic necrosis. Ozagrel had little impact on CYP2E1 activity involving the NAPQI production. In addition, ozagrel significantly attenuated cell injury induced by NAPQI in RLC-16. Conclusions We demonstrate that the TXA2 synthase inhibitor, ozagrel, dramatically alleviates liver injury induced by APAP in mice, and suggest

Fasting enhances TRAIL-mediated liver natural killer cell activity via HSP70 upregulation.

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Vu T A Dang

Full Text Available Acute starvation, which is frequently observed in clinical practice, sometimes augments the cytolytic activity of natural killer cells against neoplastic cells. In this study, we investigated the molecular mechanisms underlying the enhancement of natural killer cell function by fasting in mice. The total number of liver resident natural killer cells in a unit weight of liver tissue obtained from C57BL/6J mice did not change after a 3-day fast, while the proportions of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL+ and CD69+ natural killer cells were significantly elevated (n = 7, p <0.01, as determined by flow cytometric analysis. Furthermore, we found that TRAIL- natural killer cells that were adoptively transferred into Rag-2-/- γ chain-/- mice could convert into TRAIL+ natural killer cells in fasted mice at a higher proportion than in fed mice. Liver natural killer cells also showed high TRAIL-mediated antitumor function in response to 3-day fasting. Since these fasted mice highly expressed heat shock protein 70 (n = 7, p <0.05 in liver tissues, as determined by western blot, the role of this protein in natural killer cell activation was investigated. Treatment of liver lymphocytes with 50 µg/mL of recombinant heat shock protein 70 led to the upregulation of both TRAIL and CD69 in liver natural killer cells (n = 6, p <0.05. In addition, HSP70 neutralization by intraperitoneally injecting an anti- heat shock protein 70 monoclonal antibody into mice prior to fasting led to the downregulation of TRAIL expression (n = 6, p <0.05. These findings indicate that acute fasting enhances TRAIL-mediated liver natural killer cell activity against neoplastic cells through upregulation of heat shock protein 70.

Impaired liver regeneration is associated with reduced cyclin B1 in natural killer T cell-deficient mice.

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Ben Ya'acov, Ami; Meir, Hadar; Zolotaryova, Lydia; Ilan, Yaron; Shteyer, Eyal

2017-03-23

It has been shown that the proportion of natural killer T cells is markedly elevated during liver regeneration and their activation under different conditions can modulate this process. As natural killer T cells and liver injury are central in liver regeneration, elucidating their role is important. The aim of the current study is to explore the role of natural killer T cells in impaired liver regeneration. Concanvalin A was injected 4 days before partial hepatectomy to natural killer T cells- deficient mice or to anti CD1d1-treated mice. Ki-67 and proliferating cell nuclear antigen were used to measure hepatocytes proliferation. Expression of hepatic cyclin B1 and proliferating cell nuclear antigen were evaluated by Western Blot and liver injury was assessed by ALT and histology. Natural killer T cells- deficient or mice injected with anti CD1d antibodies exhibited reduced liver regeneration. These mice were considerably resistant to ConA-induced liver injury. In the absence of NKT cells hepatic proliferating cell nuclear antigen and cyclin B1 decreased in mice injected with Concanvalin A before partial hepatectomy. This was accompanied with reduced serum interleukin-6 levels. Natural killer T cells play an important role in liver regeneration, which is associated with cyclin B1 and interleukin-6.

Arsenite induced oxidative damage in mouse liver is associated with increased cytokeratin 18 expression

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Gonsebatt, M.E. [UNAM, Ciudad Universitaria, Dept. Medicina Genomica y Toxicologia Ambiental, Instituto de Investigaciones Biomedicas, Mexico (Mexico); Razo, L.M. del; Sanchez-Pena, L.C. [Seccion de Toxicologia, CINVESTAV, Mexico (Mexico); Cerbon, M.A. [Facultad de Quimica, UNAM, Departamento de Biologia, Mexico (Mexico); Zuniga, O.; Ramirez, P. [Facultad de Estudios Superiores Cuautitlan, UNAM, Laboratorio de Toxicologia Celular, Coordinacion General de Estudios de Posgrado e Investigacion, Cuautitlan Izcalli, Estado de Mexico (Mexico)

2007-09-15

Cytokeratins (CK) constitute a family of cytoskeletal intermediate filament proteins that are typically expressed in epithelial cells. An abnormal structure and function are effects that are clearly related to liver diseases as non-alcoholic steatohepatitis, cirrhosis and hepatocellular carcinoma. We have previously observed that sodium arsenite (SA) induced the synthesis of CK18 protein and promotes a dose-related disruption of cytoplasmic CK18 filaments in a human hepatic cell line. Both abnormal gene expression and disturbance of structural organization are toxic effects that are likely to cause liver disease by interfering with normal hepatocyte function. To investigate if a disruption in the CK18 expression pattern is associated with arsenite liver damage, we investigated CK18 mRNA and protein levels in liver slices treated with low levels of SA. Organotypic cultures were incubated with 0.01, 1 and 10 {mu}M of SA in the absence and presence of N-acetyl cysteine (NAC). Cell viability and inorganic arsenic metabolism were determined. Increased expression of CK18 was observed after exposure to SA. The addition of NAC impeded the oxidative effects of SA exposure, decreasing the production of thiobarbituric acid-reactive substances and significantly diminishing the up regulation of CK18 mRNA and protein. Liver arsenic levels correlated with increased levels of mRNA. Mice treated with intragastric single doses of 2.5 and 5 mg/kg of SA showed an increased expression of CK18. Results suggest that CK18 expression may be a sensible early biomarker of oxidative stress and damage induced by arsenite in vitro and in vivo. Then, during SA exposure, altered CK expression may compromise liver function. (orig.)

Acetaminophen-induced acute liver injury in HCV transgenic mice

International Nuclear Information System (INIS)

Uehara, Takeki; Kosyk, Oksana; Jeannot, Emmanuelle; Bradford, Blair U.; Tech, Katherine; Macdonald, Jeffrey M.; Boorman, Gary A.; Chatterjee, Saurabh; Mason, Ronald P.; Melnyk, Stepan B.; Tryndyak, Volodymyr P.; Pogribny, Igor P.; Rusyn, Ivan

2013-01-01

The exact etiology of clinical cases of acute liver failure is difficult to ascertain and it is likely that various co-morbidity factors play a role. For example, epidemiological evidence suggests that coexistent hepatitis C virus (HCV) infection increased the risk of acetaminophen-induced acute liver injury, and was associated with an increased risk of progression to acute liver failure. However, little is known about possible mechanisms of enhanced acetaminophen hepatotoxicity in HCV-infected subjects. In this study, we tested a hypothesis that HCV-Tg mice may be more susceptible to acetaminophen hepatotoxicity, and also evaluated the mechanisms of acetaminophen-induced liver damage in wild type and HCV-Tg mice expressing core, E1 and E2 proteins. Male mice were treated with a single dose of acetaminophen (300 or 500 mg/kg in fed animals; or 200 mg/kg in fasted animals; i.g.) and liver and serum endpoints were evaluated at 4 and 24 h after dosing. Our results suggest that in fed mice, liver toxicity in HCV-Tg mice is not markedly exaggerated as compared to the wild-type mice. In fasted mice, greater liver injury was observed in HCV-Tg mice. In fed mice dosed with 300 mg/kg acetaminophen, we observed that liver mitochondria in HCV-Tg mice exhibited signs of dysfunction showing the potential mechanism for increased susceptibility. -- Highlights: ► Acetaminophen-induced liver injury is a significant clinical challenge. ► HCV-infected subjects may be at higher risk for acetaminophen-induced liver injury. ► We used HCV transgenics to test if liver injury due to acetaminophen is exacerbated.

Acetaminophen-induced acute liver injury in HCV transgenic mice

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Uehara, Takeki; Kosyk, Oksana; Jeannot, Emmanuelle; Bradford, Blair U. [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599 (United States); Tech, Katherine; Macdonald, Jeffrey M. [Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 (United States); Boorman, Gary A. [Covance, Chantilly, VA 20151 (United States); Chatterjee, Saurabh; Mason, Ronald P. [Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, RTP, NC 27713 (United States); Melnyk, Stepan B. [Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72201 (United States); Tryndyak, Volodymyr P.; Pogribny, Igor P. [Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, AR 72079 (United States); Rusyn, Ivan, E-mail: iir@unc.edu [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599 (United States)

2013-01-15

The exact etiology of clinical cases of acute liver failure is difficult to ascertain and it is likely that various co-morbidity factors play a role. For example, epidemiological evidence suggests that coexistent hepatitis C virus (HCV) infection increased the risk of acetaminophen-induced acute liver injury, and was associated with an increased risk of progression to acute liver failure. However, little is known about possible mechanisms of enhanced acetaminophen hepatotoxicity in HCV-infected subjects. In this study, we tested a hypothesis that HCV-Tg mice may be more susceptible to acetaminophen hepatotoxicity, and also evaluated the mechanisms of acetaminophen-induced liver damage in wild type and HCV-Tg mice expressing core, E1 and E2 proteins. Male mice were treated with a single dose of acetaminophen (300 or 500 mg/kg in fed animals; or 200 mg/kg in fasted animals; i.g.) and liver and serum endpoints were evaluated at 4 and 24 h after dosing. Our results suggest that in fed mice, liver toxicity in HCV-Tg mice is not markedly exaggerated as compared to the wild-type mice. In fasted mice, greater liver injury was observed in HCV-Tg mice. In fed mice dosed with 300 mg/kg acetaminophen, we observed that liver mitochondria in HCV-Tg mice exhibited signs of dysfunction showing the potential mechanism for increased susceptibility. -- Highlights: ► Acetaminophen-induced liver injury is a significant clinical challenge. ► HCV-infected subjects may be at higher risk for acetaminophen-induced liver injury. ► We used HCV transgenics to test if liver injury due to acetaminophen is exacerbated.

Liver Progenitor Cell Line HepaRG Differentiated in a Bioartificial Liver Effectively Supplies Liver Support to Rats with Acute Liver Failure

NARCIS (Netherlands)

Nibourg, Geert A. A.; Chamuleau, Robert A. F. M.; van der Hoeven, Tessa V.; Maas, Martinus A. W.; Ruiter, An F. C.; Lamers, Wouter H.; Oude Elferink, Ronald P. J.; van Gulik, Thomas M.; Hoekstra, Ruurdtje

2012-01-01

A major roadblock to the application of bioartificial livers is the need for a human liver cell line that displays a high and broad level of hepatic functionality. The human bipotent liver progenitor cell line HepaRG is a promising candidate in this respect, for its potential to differentiate into

Role and mechanisms of autophagy in acetaminophen-induced liver injury.

Science.gov (United States)

Chao, Xiaojuan; Wang, Hua; Jaeschke, Hartmut; Ding, Wen-Xing

2018-04-23

Acetaminophen (APAP) overdose is the most frequent cause of acute liver failure in the USA and many other countries. Although the metabolism and pathogenesis of APAP has been extensively investigated for decades, the mechanisms by which APAP induces liver injury are incompletely known, which hampers the development of effective therapeutic approaches to tackle this important clinical problem. Autophagy is a highly conserved intracellular degradation pathway, which aims at recycling cellular components and damaged organelles in response to adverse environmental conditions and stresses as a survival mechanism. There is accumulating evidence indicating that autophagy is activated in response to APAP overdose in specific liver zone areas, and pharmacological activation of autophagy protects against APAP-induced liver injury. Increasing evidence also suggests that hepatic autophagy is impaired in nonalcoholic fatty livers (NAFLD), and NAFLD patients are more susceptible to APAP-induced liver injury. Here, we summarized the current progress on the role and mechanisms of autophagy in protecting against APAP-induced liver injury. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Perfluorooctanoic acid exposure induces endoplasmic reticulum stress in the liver and its effects are ameliorated by 4-phenylbutyrate.

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Yan, Shengmin; Zhang, Hongxia; Wang, Jianshe; Zheng, Fei; Dai, Jiayin

2015-10-01

Perfluoroalkyl acids (PFAAs) are a group of widely used anthropogenic compounds. As one of the most dominant PFAAs, perfluorooctanoic acid (PFOA) has been suggested to induce hepatotoxicity and several other toxicological effects. However, details on the mechanisms for PFOA-induced hepatotoxicity still need to be elucidated. In this study, we observed the occurrence of endoplasmic reticulum (ER) stress in mouse livers and HepG2 cells after PFOA exposure using several familiar markers for the unfolded protein response (UPR). ER stress in HepG2 cells after PFOA exposure was not significantly influenced by autophagy inhibition or stimulation. The antioxidant defense system was significantly disturbed in mouse livers after PFOA exposure, and reactive oxygen species (ROS) were increased in cells exposed to PFOA for 24 h. However, N-acetyl-L-cysteine (NAC) pretreatment did not satisfactorily alleviate the UPR in cells exposed to PFOA even though the increase of ROS was less evident. Furthermore, exposure of HepG2 cells to PFOA in the presence of sodium 4-phenylbutyrate (4-PBA), a chemical chaperone and ER stress inhibitor, suggested that 4-PBA alleviated the UPR and autophagosome accumulation induced by PFOA in cells. In addition, several toxicological effects attributed to PFOA exposure, including cell cycle arrest, proteolytic activity impairment, and neutral lipid accumulation, were also improved by 4-PBA cotreatment in cells. In vivo study demonstrated that PFOA-induced lipid metabolism perturbation and liver injury were partially ameliorated by 4-PBA in mice after 28 days of exposure. These findings demonstrated that PFOA-induced ER stress leading to UPR might play an important role in PFOA-induced hepatotoxic effects, and chemical chaperone 4-PBA could ameliorate the effects. Copyright © 2015. Published by Elsevier Inc.

Expression of miRNA-122 Induced by Liver Toxicants in Zebrafish

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Hyun-Sik Nam

2016-01-01

Full Text Available MicroRNA-122 (miRNA-122, also known as liver-specific miRNA, has recently been shown to be a potent biomarker in response to liver injury in mammals. The objective of this study was to examine its expression in response to toxicant treatment and acute liver damage, using the zebrafish system as an alternative model organism. For the hepatotoxicity assay, larval zebrafish were arrayed in 24-well plates. Adult zebrafish were also tested and arrayed in 200 mL cages. Animals were exposed to liver toxicants (tamoxifen or acetaminophen at various doses, and miRNA-122 expression levels were analyzed using qRT-PCR in dissected liver, brain, heart, and intestine, separately. Our results showed no significant changes in miRNA-122 expression level in tamoxifen-treated larvae; however, miRNA-122 expression was highly induced in tamoxifen-treated adults in a tissue-specific manner. In addition, we observed a histological change in adult liver (0.5 μM and cell death in larval liver (5 μM at different doses of tamoxifen. These results indicated that miRNA-122 may be utilized as a liver-specific biomarker for acute liver toxicity in zebrafish.

Liver restores immune homeostasis after local inflammation despite the presence of autoreactive T cells.

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Kathie Béland

Full Text Available The liver must keep equilibrium between immune tolerance and immunity in order to protect itself from pathogens while maintaining tolerance to food antigens. An imbalance between these two states could result in an inflammatory liver disease. The aims of this study were to identify factors responsible for a break of tolerance and characterize the subsequent restoration of liver immune homeostasis. A pro-inflammatory environment was created in the liver by the co-administration of TLR ligands CpG and Poly(I:C in presence or absence of activated liver-specific autoreactive CD8(+ T cells. Regardless of autoreactive CD8(+ T cells, mice injected with CpG and Poly(I:C showed elevated serum ALT levels and a transient liver inflammation. Both CpG/Poly(I:C and autoreactive CD8(+T cells induced expression of TLR9 and INF-γ by the liver, and an up-regulation of homing and adhesion molecules CXCL9, CXCL10, CXCL16, ICAM-1 and VCAM-1. Transferred CFSE-labeled autoreactive CD8(+ T cells, in presence of TLR3 and 9 ligands, were recruited by the liver and spleen and proliferated. This population then contracted by apoptosis through intrinsic and extrinsic pathways. Up-regulation of FasL and PD-L1 in the liver was observed. In conclusion, TLR-mediated activation of the innate immune system results in a pro-inflammatory environment that promotes the recruitment of lymphocytes resulting in bystander hepatitis. Despite this pro-inflammatory environment, the presence of autoreactive CD8(+ T cells is not sufficient to sustain an autoimmune response against the liver and immune homeostasis is rapidly restored through the apoptosis of T cells.

Liver restores immune homeostasis after local inflammation despite the presence of autoreactive T cells.

Science.gov (United States)

Béland, Kathie; Lapierre, Pascal; Djilali-Saiah, Idriss; Alvarez, Fernando

2012-01-01

The liver must keep equilibrium between immune tolerance and immunity in order to protect itself from pathogens while maintaining tolerance to food antigens. An imbalance between these two states could result in an inflammatory liver disease. The aims of this study were to identify factors responsible for a break of tolerance and characterize the subsequent restoration of liver immune homeostasis. A pro-inflammatory environment was created in the liver by the co-administration of TLR ligands CpG and Poly(I:C) in presence or absence of activated liver-specific autoreactive CD8(+) T cells. Regardless of autoreactive CD8(+) T cells, mice injected with CpG and Poly(I:C) showed elevated serum ALT levels and a transient liver inflammation. Both CpG/Poly(I:C) and autoreactive CD8(+)T cells induced expression of TLR9 and INF-γ by the liver, and an up-regulation of homing and adhesion molecules CXCL9, CXCL10, CXCL16, ICAM-1 and VCAM-1. Transferred CFSE-labeled autoreactive CD8(+) T cells, in presence of TLR3 and 9 ligands, were recruited by the liver and spleen and proliferated. This population then contracted by apoptosis through intrinsic and extrinsic pathways. Up-regulation of FasL and PD-L1 in the liver was observed. In conclusion, TLR-mediated activation of the innate immune system results in a pro-inflammatory environment that promotes the recruitment of lymphocytes resulting in bystander hepatitis. Despite this pro-inflammatory environment, the presence of autoreactive CD8(+) T cells is not sufficient to sustain an autoimmune response against the liver and immune homeostasis is rapidly restored through the apoptosis of T cells.

Environmentally toxicant exposures induced intragenerational transmission of liver abnormalities in mice

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Mohamed A. Al-Griw

2017-08-01

Full Text Available Environmental toxicants such as chemicals, heavy metals, and pesticides have been shown to promote transgenerational inheritance of abnormal phenotypes and/or diseases to multiple subsequent generations following parental and/ or ancestral exposures. This study was designed to examine the potential transgenerational action of the environmental toxicant trichloroethane (TCE on transmission of liver abnormality, and to elucidate the molecular etiology of hepatocyte cell damage. A total of thirty two healthy immature female albino mice were randomly divided into three equal groups as follows: a sham group, which did not receive any treatment; a vehicle group, which received corn oil alone, and TCE treated group (3 weeks, 100 μg/kg i.p., every 4th day. The F0 and F1 generation control and TCE populations were sacrificed at the age of four months, and various abnormalities histpathologically investigated. Cell death and oxidative stress indices were also measured. The present study provides experimental evidence for the inheritance of environmentally induced liver abnormalities in mice. The results of this study show that exposure to the TCE promoted adult onset liver abnormalities in F0 female mice as well as unexposed F1 generation offspring. It is the first study to report a transgenerational liver abnormalities in the F1 generation mice through maternal line prior to gestation. This finding was based on careful evaluation of liver histopathological abnormalities, apoptosis of hepatocytes, and measurements of oxidative stress biomarkers (lipid peroxidation, protein carbonylation, and nitric oxide in control and TCE populations. There was an increase in liver histopathological abnormalities, cell death, and oxidative lipid damage in F0 and F1 hepatic tissues of TCE treated group. In conclusion, this study showed that the biological and health impacts of environmental toxicant TCE do not end in maternal adults, but are passed on to offspring

Suppression of immune-mediated liver injury after vaccination with attenuated pathogenic cells.

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Mei, Yunhua; Wang, Ying; Xu, Lingyun

2007-05-15

Cell vaccination via immunization with attenuated pathogenic cells is an effective preventive method that has been successfully applied in several animal models of inflammatory or autoimmune diseases. Concanavalin A (Con A)-induced hepatitis (CIH) is a commonly used experimental model to study immune-mediated liver injury. Multiple cell types including T lymphocytes, macrophages and neutrophils have been found to be involved in the pathogenesis of CIH. In this study, we used attenuated spleen lymphocytes or peripheral blood lymphocytes as vaccines to investigate whether they could induce protective immune responses to prevent mice from developing CIH. We found that mice receiving such vaccination before CIH induction developed much milder diseases, exhibited a lower level of alanine aminotransferase (ALT) released into their plasma and had less inflammatory lesions in their livers. Such CIH-suppression is dose- and frequency-dependent. The suppressive effect was associated with inhibition of several major inflammatory mediators, pro-inflammatory cytokines and chemokines.

Reduced Expression of the Liver/Beta-Cell Glucose Transporter Isoform in Glucose-Insensitive Pancreatic Beta Cells of Diabetic Rats

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Thorens, Bernard; Weir, Gordon C.; Leahy, John L.; Lodish, Harvey F.; Bonner-Weir, Susan

1990-09-01

Rats injected with a single dose of streptozocin at 2 days of age develop non-insulin-dependent diabetes 6 weeks later. The pancreatic beta islet cells of these diabetic rats display a loss of glucose-induced insulin secretion while maintaining sensitivity to other secretagogues such as arginine. We analyzed the level of expression of the liver/beta-cell glucose transporter isoform in diabetic islets by immunofluorescence staining of pancreas sections and by Western blotting of islet lysates. Islets from diabetic animals have a reduced expression of this beta-cell-specific glucose transporter isoform and the extent of reduction is correlated with the severity of hyperglycemia. In contrast, expression of this transporter isoform in liver is minimally modified by the diabetes. Thus a decreased expression of the liver/beta-cell glucose transporter isoform in beta cells is associated with the impaired glucose sensing characteristic of diabetic islets; our data suggest that this glucose transporter may be part of the beta-cell glucose sensor.

Assessing Concordance of Drug-Induced Transcriptional Response in Rodent Liver and Cultured Hepatocytes.

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Jeffrey J Sutherland

2016-03-01

Full Text Available The effect of drugs, disease and other perturbations on mRNA levels are studied using gene expression microarrays or RNA-seq, with the goal of understanding molecular effects arising from the perturbation. Previous comparisons of reproducibility across laboratories have been limited in scale and focused on a single model. The use of model systems, such as cultured primary cells or cancer cell lines, assumes that mechanistic insights derived from the models would have been observed via in vivo studies. We examined the concordance of compound-induced transcriptional changes using data from several sources: rat liver and rat primary hepatocytes (RPH from Drug Matrix (DM and open TG-GATEs (TG, human primary hepatocytes (HPH from TG, and mouse liver/HepG2 results from the Gene Expression Omnibus (GEO repository. Gene expression changes for treatments were normalized to controls and analyzed with three methods: 1 gene level for 9071 high expression genes in rat liver, 2 gene set analysis (GSA using canonical pathways and gene ontology sets, 3 weighted gene co-expression network analysis (WGCNA. Co-expression networks performed better than genes or GSA when comparing treatment effects within rat liver and rat vs. mouse liver. Genes and modules performed similarly at Connectivity Map-style analyses, where success at identifying similar treatments among a collection of reference profiles is the goal. Comparisons between rat liver and RPH, and those between RPH, HPH and HepG2 cells reveal lower concordance for all methods. We observe that the baseline state of untreated cultured cells relative to untreated rat liver shows striking similarity with toxicant-exposed cells in vivo, indicating that gross systems level perturbation in the underlying networks in culture may contribute to the low concordance.

Hepatic stellate cell and myofibroblast-like cell gene expression in the explanted cirrhotic livers of patients undergoing liver transplantation.

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Estep, J Michael; O'Reilly, Linda; Grant, Geraldine; Piper, James; Jonsson, Johann; Afendy, Arian; Chandhoke, Vikas; Younossi, Zobair M

2010-02-01

Hepatic stellate cells (HSC) are involved in hepatic fibrogenesis. Cell signaling associated with an insult to the liver affects an HSC transdifferentiation to fibrogenic myofibroblast-like cells. To investigate the transcriptional expression distinguishing HSC and myofibroblast-like cells between livers with and without cirrhosis. Tissue from ten cirrhotic livers (undergoing transplant) and four non-cirrhotic livers from the National Disease Research Interchange underwent cell separation to extract HSC and myofibroblast-like cell populations. Separated cell types as well as LI-90 cells were subjected to microarray analysis. Selected microarray results were verified by quantitative real-time PCR. Differential expression of some genes, such as IL-1beta, IL-1alpha, and IL-6, was associated with both transdifferentiation and disease. Other genes, such as fatty acid 2-hydroxylase only show differential expression in association with disease. Functional analysis supported these findings, indicating some signal transduction pathways (IL-6) are involved in disease and activation, whereas retinoid X receptor signaling in HSC from cirrhotic and non-cirrhotic livers varies in scope and quality. These findings indicate distinct phenotypes for HSC from cirrhotic and non-cirrhotic livers. Furthermore, coordinated differential expression between genes involved in the same signal transduction pathways provides some insight into the mechanisms that may control the balance between fibrogenesis and fibrolysis.

Aloe vera attenuated liver injury in mice with acetaminophen-induced hepatitis.

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Werawatganon, Duangporn; Linlawan, Sittikorn; Thanapirom, Kessarin; Somanawat, Kanjana; Klaikeaw, Naruemon; Rerknimitr, Rungsun; Siriviriyakul, Prasong

2014-07-08

An overdose of the acetaminophen causes liver injury. This study aims to examine the anti-oxidative, anti-inflammatory effects of Aloe vera in mice with acetaminophen induced hepatitis. Male mice were randomly divided into three groups (n = 8 each). Control group were given orally distilled water (DW). APAP group were given orally N-acetyl-P-aminophenol (APAP) 400 mg/kg suspended in DW. Aloe vera-treated group were given orally APAP and Aloe vera (150 mg/kg) suspended in DW. Twenty-four hours later, the liver was removed to determine hepatic malondialdehyde (MDA), hepatic glutathione (GSH), the number of interleukin (IL)-12 and IL-18 positive stained cells (%) by immunohistochemistry method, and histopathological examination. Then, the serum was collected to determine transaminase (ALT). In APAP group, ALT, hepatic MDA and the number of IL-12 and IL-18 positive stained cells were significantly increased when compared to control group (1210.50 ± 533.86 vs 85.28 ± 28.27 U/L, 3.60 ± 1.50 vs 1.38 ± 0.15 nmol/mg protein, 12.18 ± 1.10 vs 1.84 ± 1.29%, and 13.26 ± 0.90 vs 2.54 ± 1.29%, P = 0.000, respectively), whereas hepatic GSH was significantly decreased when compared to control group (5.98 ± 0.30 vs 11.65 ± 0.43 nmol/mg protein, P = 0.000). The mean level of ALT, hepatic MDA, the number of IL-12 and IL-18 positive stained cells, and hepatic GSH in Aloe vera-treated group were improved as compared with APAP group (606.38 ± 495.45 vs 1210.50 ± 533.86 U/L, P = 0.024; 1.49 ± 0.64 vs 3.60 ± 1.50 nmol/mg protein, P = 0.001; 5.56 ± 1.25 vs 12.18 ± 1.10%, P = 0.000; 6.23 ± 0.94 vs 13.26 ± 0.90%, P = 0.000; and 10.02 ± 0.20 vs 5.98 ± 0.30 nmol/mg protein, P = 0.000, respectively). Moreover, in the APAP group, the liver showed extensive hemorrhagic hepatic necrosis at all zones while in Aloe vera-treated group, the liver architecture was improved histopathology. APAP overdose can cause liver injury. Our result indicate that Aloe vera attenuate APAP-induced

Edaravone protects endotoxin-induced liver injury by inhibiting apoptosis and reducing proinflammatory cytokines

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L. Zong

2014-03-01

Full Text Available Studies have shown that edaravone may prevent liver injury. This study aimed to investigate the effects of edaravone on the liver injury induced by D-galactosamine (GalN and lipopolysaccharide (LPS in female BALB/c mice. Edaravone was injected into mice 30 min before and 4 h after GalN/LPS injection. The survival rate was determined within the first 24 h. Animals were killed 8 h after GalN/LPS injection, and liver injury was biochemically and histologically assessed. Hepatocyte apoptosis was measured by TUNEL staining; proinflammatory cytokines [tumor necrosis factor-α (TNF-α and interleukin-6 (IL-6] in the liver were assayed by ELISA; expression of caspase-8 and caspase-3 proteins was detected by Western blot assay; and caspase-3 activity was also determined. Results showed that GalN/LPS induced marked elevations in serum aspartate aminotransferase (AST and alanine aminotransferase (ALT. Edaravone significantly inhibited elevation of serum AST and ALT, accompanied by an improvement in histological findings. Edaravone lowered the levels of TNF-α and IL-6 and reduced the number of TUNEL-positive cells. In addition, 24 h after edaravone treatment, caspase-3 activity and mortality were reduced. Edaravone may effectively ameliorate GalN/LPS-induced liver injury in mice by reducing proinflammatory cytokines and inhibiting apoptosis.

Ethanol extract from portulaca oleracea L. attenuated acetaminophen-induced mice liver injury

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Liu, Xue-Feng; Zheng, Cheng-Gang; Shi, Hong-Guang; Tang, Gu-Sheng; Wang, Wan-Yin; Zhou, Juan; Dong, Li-Wei

2015-01-01

Acetaminophen-induced liver injury represents the most frequent cause of drug-induced liver failure in the world. Portulaca oleracea L., a widely distributed weed, has been used as a folk medicine in many countries. Previously, we reported that the ethanol extracts of Portulaca oleracea L. (PO) exhibited significant anti-hypoxic activity. In the present study, we investigated the role of PO on acetaminophen (APAP) induced hepatotoxicity. The results demonstrated that PO was an effective anti-oxidative agent, which could, to some extent, reverse APAP-induced hepatotoxicity by regulating the reactive oxygen species (ROS) in the liver of mice. At the same time, PO treatment significantly decreased mice serum levels of IL-6 and TNFα and their mRNA expression in liver tissue IL-α and TNFα play an important role during APAP-induced liver injury. Furthermore, PO inhibited APAP and TNFα-induced activation of JNK, whose activation play an important effect during APAP induced liver injury. These findings suggested that administration of PO may be an effective strategy to prevent or treat liver injury induced by APAP. PMID:25901199

Acute liver injury induced by weight-loss herbal supplements.

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Chen, Gary C; Ramanathan, Vivek S; Law, David; Funchain, Pauline; Chen, George C; French, Samuel; Shlopov, Boris; Eysselein, Viktor; Chung, David; Reicher, Sonya; Pham, Binh V

2010-11-27

We report three cases of patients with acute liver injury induced by weight-loss herbal supplements. One patient took Hydroxycut while the other two took Herbalife supplements. Liver biopsies for all patients demonstrated findings consistent with drug-induced acute liver injury. To our knowledge, we are the first institute to report acute liver injury from both of these two types of weight-loss herbal supplements together as a case series. The series emphasizes the importance of taking a cautious approach when consuming herbal supplements for the purpose of weight loss.

Choline-Deficient-Diet-Induced Fatty Liver Is a Metastasis-Resistant Microenvironment.

Science.gov (United States)

Nakamura, Miki; Suetsugu, Atsushi; Hasegawa, Kosuke; Matsumoto, Takuro; Aoki, Hitomi; Kunisada, Takahiro; Shimizu, Masahito; Saji, Shigetoyo; Moriwaki, Hisataka; Hoffman, Robert M

2017-07-01

Fatty liver disease is increasing in the developed and developing world. Liver metastasis from malignant lymphoma in the fatty liver is poorly understood. In a previous report, we developed color-coded imaging of the tumor microenvironment (TME) of the murine EL4-RFP malignant lymphoma during metastasis, including the lung. In the present report, we investigated the potential and microenvironment of the fatty liver induced by a choline-deficient diet as a metastatic site in this mouse lymphoma model. C57BL/6-GFP transgenic mice were fed with a choline-deficient diet in order to establish a fatty liver model. EL4-RFP cells were injected in the spleen of normal mice and fatty-liver mice. Metastases in mice with fatty liver or normal liver were imaged with the Olympus SZX7 microscope and the Olympus FV1000 confocal microscope. Metastases of EL4-RFP were observed in the liver, ascites and bone marrow. Primary tumors were imaged in the spleen at the injection site. The fewest metastases were observed in the fatty liver. In addition, the fewest cancer-associated fibroblasts (CAFs) were observed in the fatty liver. The relative metastatic resistance of the fatty liver may be due to the reduced number of CAFs in the fatty livers. The mechanism of the effect of the choline-deficient diet is discussed. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Protective role of garlic against gamma radiation induced histological and histochemical changes in rat liver

International Nuclear Information System (INIS)

Abdel Motaal, N.A.; Abdel Maguid, A.

2007-01-01

The present work was planned to evaluate the radioprotective effect of garlic (Allium sativum) against the hazardous action of gamma radiation on liver of rat one and ten days post-exposure. Garlic was orally administered (100 mg/ kg body wt) to rats daily for two weeks before exposure to single dose whole body gamma-irradiation (5Gy). The results showed that exposure of rats to gamma- irradiation caused massive portal infiltration with inflammatory cells, dilatation of blood sinusoids, an increase in the number of Kupffer cells, vacuolation of some hepatocytes as well as pyknosis and karyolysis of hepatic nuclei in the liver tissue. Histochemical examination of liver one day post- irradiation illustrated weak to moderate glycogen particles. While, on ten days post-irradiation, a strong activity for glycogen was detected. The disturbance in carbohydrate metabolism is closely related to the radiation induced histological damage in the liver tissue. Administration of garlic for 2 weeks pre-irradiation reduced the radiation induced histopathological changes and showed marked protection against the tissue damaging effect of radiation. It could be concluded that treatment of rats with garlic before exposure to gamma-irradiation offered a noticeable radioprotective effect of the studied organ

in Human Liver Diseases

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Minoru Fujimoto

2010-01-01

Full Text Available Toll-like receptor (TLR signaling pathways are strictly coordinated by several mechanisms to regulate adequate innate immune responses. Recent lines of evidence indicate that the suppressor of cytokine signaling (SOCS family proteins, originally identified as negative-feedback regulators in cytokine signaling, are involved in the regulation of TLR-mediated immune responses. SOCS1, a member of SOCS family, is strongly induced upon TLR stimulation. Cells lacking SOCS1 are hyperresponsive to TLR stimulation. Thus, SOCS1 is an important regulator for both cytokine and TLR-induced responses. As an immune organ, the liver contains various types of immune cells such as T cells, NK cells, NKT cells, and Kupffer cells and is continuously challenged with gut-derived bacterial and dietary antigens. SOCS1 may be implicated in pathophysiology of the liver. The studies using SOCS1-deficient mice revealed that endogenous SOCS1 is critical for the prevention of liver diseases such as hepatitis, cirrhosis, and cancers. Recent studies on humans suggest that SOCS1 is involved in the development of various liver disorders in humans. Thus, SOCS1 and other SOCS proteins are potential targets for the therapy of human liver diseases.

Analytical study of cell liver proliferation and serum AFP in various liver diseases other than hepatomas

Energy Technology Data Exchange (ETDEWEB)

Takino, T; Okuda, K; Kitamura, O; Takahashi, T; Ashihara, T [Kyoto Prefectural Univ. of Medicine (Japan)

1974-12-01

Cell proliferative activity in the liver tissue obtained in 50 cases by liver biopsy, was analyzed using in vitro labeling of /sup 3/H-thymidine autoradiography. The proliferating cells were found to be located mainly in the periportal areas of the lobules. The mean labeling indices of the liver cells were 0.06 % in chronic hepatitis in its active form, 0.05 % in pre-cirrhosis of the liver, 0.03 % in liver cirrhosis, 0.02 % in chronic hepatitis in an inactive form and 0.018 % in acute hepatitis at the restoractive stage. The labeling indices of the liver parenchymal cells of each specimen studied were very low being at most 0.2 %. On the other hand, when the serum AFP was analyzed by radioimmunoassay technique in 185 patients with various liver diseases, level of the mean serum AFP in each group of the liver diseases was found to correspond to that of the proliferative activity of the liver cells in its respective group. From these data it was suggested that the proliferative activity of the liver cells in various liver diseases, with the exception of hepatomas, was closely related to release of AFP into the serum.

Mechanisms of the hepatoprotective effects of tamoxifen against drug-induced and chemical-induced acute liver injuries

Energy Technology Data Exchange (ETDEWEB)

Yoshikawa, Yukitaka; Miyashita, Taishi; Higuchi, Satonori [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan); Tsuneyama, Koichi [Department of Diagnostic Pathology, Graduate School of Medicine and Pharmaceutical Science for Research, University of Toyama, Sugitani, Toyama 930‐0194 (Japan); Endo, Shinya [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan); Tsukui, Tohru [Research Center for Genomic Medicine, Saitama Medical University, Yamane, Hidaka 350‐1241 (Japan); Toyoda, Yasuyuki; Fukami, Tatsuki; Nakajima, Miki [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan); Yokoi, Tsuyoshi, E-mail: tyokoi@p.kanazawa-u.ac.jp [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan)

2012-10-01

Although estrogen receptor (ER)α agonists, such as estradiol and ethinylestradiol (EE2), cause cholestasis in mice, they also reduce the degree of liver injury caused by hepatotoxicants as well as ischemia–reperfusion. The functional mechanisms of ERα have yet to be elucidated in drug-induced or chemical-induced liver injury. The present study investigated the effects of an ERα agonist, selective ER modulators (SERMs) and an ER antagonist on drug-induced and chemical-induced liver injuries caused by acetaminophen, bromobenzene, diclofenac, and thioacetamide (TA). We observed hepatoprotective effects of EE2, tamoxifen (TAM) and raloxifene pretreatment in female mice that were exposed to a variety of hepatotoxic compounds. In contrast, the ER antagonist did not show any hepatoprotective effects. DNA microarray analyses suggested that monocyte to macrophage differentiation-associated 2 (Mmd2) protein, which has an unknown function, is commonly increased by TAM and RAL pretreatment, but not by pretreatment with the ER antagonist. In ERα-knockout mice, the hepatoprotective effects of TAM and the increased expression of Mmd2 mRNA were not observed in TA-induced liver injury. To investigate the function of Mmd2, the expression level of Mmd2 mRNA was significantly knocked down to approximately 30% in mice by injection of siRNA for Mmd2 (siMmd2). Mmd2 knockdown resulted in a reduction of the protective effects of TAM on TA-induced liver injury in mice. This is the first report of the involvement of ERα in drug-induced or chemical-induced liver injury. Upregulation of Mmd2 protein in the liver was suggested as the mechanism of the hepatoprotective effects of EE2 and SERMs. -- Highlights: ► Liver injury induced by drugs or chemicals was investigated in mice. ► Liver injury was suppressed by pretreatment with tamoxifen in female mice. ► Mmd2, whose function was unknown, could be a candidate gene for liver protection. ► Tamoxifen up-regulated Mmd2 mRNA expression

Mechanisms of the hepatoprotective effects of tamoxifen against drug-induced and chemical-induced acute liver injuries

International Nuclear Information System (INIS)

Yoshikawa, Yukitaka; Miyashita, Taishi; Higuchi, Satonori; Tsuneyama, Koichi; Endo, Shinya; Tsukui, Tohru; Toyoda, Yasuyuki; Fukami, Tatsuki; Nakajima, Miki; Yokoi, Tsuyoshi

2012-01-01

Although estrogen receptor (ER)α agonists, such as estradiol and ethinylestradiol (EE2), cause cholestasis in mice, they also reduce the degree of liver injury caused by hepatotoxicants as well as ischemia–reperfusion. The functional mechanisms of ERα have yet to be elucidated in drug-induced or chemical-induced liver injury. The present study investigated the effects of an ERα agonist, selective ER modulators (SERMs) and an ER antagonist on drug-induced and chemical-induced liver injuries caused by acetaminophen, bromobenzene, diclofenac, and thioacetamide (TA). We observed hepatoprotective effects of EE2, tamoxifen (TAM) and raloxifene pretreatment in female mice that were exposed to a variety of hepatotoxic compounds. In contrast, the ER antagonist did not show any hepatoprotective effects. DNA microarray analyses suggested that monocyte to macrophage differentiation-associated 2 (Mmd2) protein, which has an unknown function, is commonly increased by TAM and RAL pretreatment, but not by pretreatment with the ER antagonist. In ERα-knockout mice, the hepatoprotective effects of TAM and the increased expression of Mmd2 mRNA were not observed in TA-induced liver injury. To investigate the function of Mmd2, the expression level of Mmd2 mRNA was significantly knocked down to approximately 30% in mice by injection of siRNA for Mmd2 (siMmd2). Mmd2 knockdown resulted in a reduction of the protective effects of TAM on TA-induced liver injury in mice. This is the first report of the involvement of ERα in drug-induced or chemical-induced liver injury. Upregulation of Mmd2 protein in the liver was suggested as the mechanism of the hepatoprotective effects of EE2 and SERMs. -- Highlights: ► Liver injury induced by drugs or chemicals was investigated in mice. ► Liver injury was suppressed by pretreatment with tamoxifen in female mice. ► Mmd2, whose function was unknown, could be a candidate gene for liver protection. ► Tamoxifen up-regulated Mmd2 mRNA expression

Evaluation of Protective Activity of Curcumin in Reducing Methotrexate Induced Liver Cells Injury: An Experimental Study on Iraqi White Domestic Rabbits

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Hussain Abady Aljebori

2018-03-01

Full Text Available Background: Hepatotoxicity is a common problem in medical practice, most of the commonly used drugs are potentially hepatotoxic. Although Methotrexate is a hepa- toxic drug, it is widely used in the treatment of many cancerous and non-cancerous conditions because of its cytotoxic and immunosuppressant activity. Curcumin con- tains a variety of natural substances with antioxidant properties, it is widely used in  folk medicine.Antioxidant activity of Curcumin can reduce liver cell injury induced by Methotrexate administration. Objective: The research aims to study the methotrexate hepatoxicity on rabbits, and the hepatoprotective activity of Curcumin. Materials and Methods: Thirty white domestic rabbits were bought from animal market and grouped randomly into three groups; control group received intraperitoneal normal saline, methotrexate group received 6.5 mg/Kgm body weight intraperitoneal methotrexate, and curcumin group received oral Curcumin in addition to intraperitoneal methotrexate. Results: The study showed abnormal liver function tests, INR, liver tissues oxida- tive markers, and liver cell injury on histopathology in Methotrexate group, and normal findings in Curcumin groups. Conclusion: It is concluded that the Methotrexate is a hepatotoxic drug. The results also shoe that the concomitant administration of Curcumin reduced hepatotoxicity. Recommendation: It is recommended to use of Curcumin in clinical practice as a food supplement to patient receiving methotrexate to reduce hepatotoxicity.

Fenofibrate, a peroxisome proliferator-activated receptor α ligand, prevents abnormal liver function induced by a fasting–refeeding process

International Nuclear Information System (INIS)

Lee, Joon No; Dutta, Raghbendra Kumar; Kim, Seul-Gi; Lim, Jae-Young; Kim, Se-Jin; Choe, Seong-Kyu; Yoo, Kyeong-Won; Song, Seung Ryel; Park, Do-Sim; So, Hong-Seob; Park, Raekil

2013-01-01

Highlights: •A fasting–refeeding high fat diet (HDF) model mimics irregular eating habit. •A fasting–refeeding HFD induces liver ballooning injury. •A fasting–refeeding HDF process elicits hepatic triglyceride accumulation. •Fenofibrate, PPARα ligand, prevents liver damage induced by refeeding HFD. -- Abstract: Fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, is an anti-hyperlipidemic agent that has been widely used in the treatment of dyslipidemia. In this study, we examined the effect of fenofibrate on liver damage caused by refeeding a high-fat diet (HFD) in mice after 24 h fasting. Here, we showed that refeeding HFD after fasting causes liver damage in mice determined by liver morphology and liver cell death. A detailed analysis revealed that hepatic lipid droplet formation is enhanced and triglyceride levels in liver are increased by refeeding HFD after starvation for 24 h. Also, NF-κB is activated and consequently induces the expression of TNF-α, IL1-β, COX-2, and NOS2. However, treating with fenofibrate attenuates the liver damage and triglyceride accumulation caused by the fasting–refeeding HFD process. Fenofibrate reduces the expression of NF-κB target genes but induces genes for peroxisomal fatty acid oxidation, peroxisome biogenesis and mitochondrial fatty acid oxidation. These results strongly suggest that the treatment of fenofibrate ameliorates the liver damage induced by fasting–refeeding HFD, possibly through the activation of fatty acid oxidation

Fenofibrate, a peroxisome proliferator-activated receptor α ligand, prevents abnormal liver function induced by a fasting–refeeding process

Energy Technology Data Exchange (ETDEWEB)

Lee, Joon No; Dutta, Raghbendra Kumar; Kim, Seul-Gi; Lim, Jae-Young; Kim, Se-Jin; Choe, Seong-Kyu [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Yoo, Kyeong-Won [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Immune-network Pioneer Research Center, Department of Biochemistry, College of Medicine, Dong-A University, Busan (Korea, Republic of); Song, Seung Ryel [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Park, Do-Sim [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Department of Laboratory of Medicine, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); So, Hong-Seob [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Park, Raekil [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of)

2013-12-06

Highlights: •A fasting–refeeding high fat diet (HDF) model mimics irregular eating habit. •A fasting–refeeding HFD induces liver ballooning injury. •A fasting–refeeding HDF process elicits hepatic triglyceride accumulation. •Fenofibrate, PPARα ligand, prevents liver damage induced by refeeding HFD. -- Abstract: Fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, is an anti-hyperlipidemic agent that has been widely used in the treatment of dyslipidemia. In this study, we examined the effect of fenofibrate on liver damage caused by refeeding a high-fat diet (HFD) in mice after 24 h fasting. Here, we showed that refeeding HFD after fasting causes liver damage in mice determined by liver morphology and liver cell death. A detailed analysis revealed that hepatic lipid droplet formation is enhanced and triglyceride levels in liver are increased by refeeding HFD after starvation for 24 h. Also, NF-κB is activated and consequently induces the expression of TNF-α, IL1-β, COX-2, and NOS2. However, treating with fenofibrate attenuates the liver damage and triglyceride accumulation caused by the fasting–refeeding HFD process. Fenofibrate reduces the expression of NF-κB target genes but induces genes for peroxisomal fatty acid oxidation, peroxisome biogenesis and mitochondrial fatty acid oxidation. These results strongly suggest that the treatment of fenofibrate ameliorates the liver damage induced by fasting–refeeding HFD, possibly through the activation of fatty acid oxidation.

Liver fibrosis in mice induced by carbon tetrachloride and its reversion by luteolin

International Nuclear Information System (INIS)

Domitrovic, Robert; Jakovac, Hrvoje; Tomac, Jelena; Sain, Ivana

2009-01-01

Hepatic fibrosis is effusive wound healing process in which excessive connective tissue builds up in the liver. Because specific treatments to stop progressive fibrosis of the liver are not available, we have investigated the effects of luteolin on carbon tetrachloride (CCl 4 )-induced hepatic fibrosis. Male Balb/C mice were treated with CCl 4 (0.4 ml/kg) intraperitoneally (i.p.), twice a week for 6 weeks. Luteolin was administered i.p. once daily for next 2 weeks, in doses of 10, 25, and 50 mg/kg of body weight. The CCl 4 control group has been observed for spontaneous reversion of fibrosis. CCl 4 -intoxication increased serum aminotransferase and alkaline phosphatase levels and disturbed hepatic antioxidative status. Most of these parameters were spontaneously normalized in the CCl 4 control group, although the progression of liver fibrosis was observed histologically. Luteolin treatment has increased hepatic matrix metalloproteinase-9 levels and metallothionein (MT) I/II expression, eliminated fibrinous deposits and restored architecture of the liver in a dose-dependent manner. Concomitantly, the expression of glial fibrillary acidic protein and α-smooth muscle actin indicated deactivation of hepatic stellate cells. Our results suggest the therapeutic effects of luteolin on CCl 4 -induced liver fibrosis by promoting extracellular matrix degradation in the fibrotic liver tissue and the strong enhancement of hepatic regenerative capability, with MTs as a critical mediator of liver regeneration.

FC-99 ameliorates sepsis-induced liver dysfunction by modulating monocyte/macrophage differentiation via Let-7a related monocytes apoptosis.

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Zhao, Yarong; Zhu, Haiyan; Wang, Haining; Ding, Liang; Xu, Lizhi; Chen, Dai; Shen, Sunan; Hou, Yayi; Dou, Huan

2018-03-13

The liver is a vital target for sepsis-related injury, leading to inflammatory pathogenesis, multiple organ dysfunction and high mortality rates. Monocyte-derived macrophage transformations are key events in hepatic inflammation. N 1 -[(4-methoxy)methyl]-4-methyl-1,2-benzenediamine (FC-99) previously displayed therapeutic potential on experimental sepsis. However, the underlying mechanism of this protective effect is still not clear. FC-99 treatment attenuated the liver dysfunction in septic mice that was accompanied with reduced numbers of pro-inflammatory Ly6C hi monocytes in the peripheral blood and CD11b + F4/80 lo monocyte-derived macrophages in the liver. These effects were attributed to the FC-99-induced apoptosis of CD11b + cells. In PMA-differentiated THP-1 cells, FC-99 repressed the expression of CD11b, CD14 and caspase3 and resulted in a high proportion of Annexin V + cells. Moreover, let-7a-5p expression was abrogated upon CLP stimulation in vivo , whereas it was restored by FC-99 treatment. TargetScan analysis and luciferase assays indicated that the anti-apoptotic protein BCL-XL was targeted by let-7a-5p. BCL-XL was inhibited by FC-99 in order to induce monocyte apoptosis, leading to the impaired monocyte-to-macrophage differentiation. Murine acute liver failure was generated by caecal ligation puncture surgery after FC-99 administration; Blood samples and liver tissues were collected to determine the monocyte/macrophage subsets and the induction of apoptosis. Human acute monocytic leukemia cell line (THP-1) cells were pretreated with FC-99 followed by phorbol-12-myristate-13-acetate (PMA) stimulation, in order to induce monocyte-to-macrophage differentiation. The target of FC-99 and the mechanistic analyses were conducted by microarrays, qRT-PCR validation, TargetScan algorithms and a luciferase report assay. FC-99 exhibits potential therapeutic effects on CLP-induced liver dysfunction by restoring let-7a-5p levels.

Propylthiouracil-induced liver failure and artificial liver support systems: a case report and review of the literature

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Wu DB

2017-01-01

Full Text Available Dong-Bo Wu,1,2 En-Qiang Chen,1,2 Lang Bai,1,2 Hong Tang1,2 1Center of Infectious Diseases, West China Hospital of Sichuan University, 2Division of Molecular Biology of Infectious Diseases, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, People’s Republic of China Background: Antithyroid drugs carry a potential risk of hepatotoxicity. Propylthiouracil (PTU is commonly prescribed for patients with hyperthyroidism. PTU, however, can induce liver injury, ranging from mild asymptomatic elevation of aminotransferases to acute liver failure (ALF.Case presentation: This case reports on a 16-year-old Chinese girl with hyperthyroidism, who was admitted to our hospital for jaundice, nausea, and fatigue associated with severe hyperbilirubinemia and coagulopathy. She had been prescribed PTU 5 months earlier. There was no history of hypersensitivity to drugs, viral liver diseases, blood transfusion, or surgery. On the basis of her symptoms and the clinical data, she was diagnosed with PTU-induced ALF. Due to the limited number of available donor organs for liver transplantation, she was started on treatment with artificial liver support system (ALSS. After four sessions of ALSS, her clinical signs and symptoms were found to be markedly improved, and she was discharged 25 days after admission. Four months later, her liver function normalized.Conclusion: Although PTU-induced liver failure is rare in clinical practice, liver function should be appropriately monitored during treatment with PTU. PTU-induced ALF in this patient was successfully managed with an ALSS, suggesting that the latter may be an alternative to liver transplantation. Keywords: propylthiouracil, liver injury, acute liver failure, artificial liver support systems 

Diphenhydramine as a Cause of Drug-Induced Liver Injury

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Yunseok Namn

2017-01-01

Full Text Available Drug-induced liver injury (DILI is the most common cause of acute liver failure in the Unites States and accounts for 10% of acute hepatitis cases. We report the only known case of diphenhydramine-induced acute liver injury in the absence of concomitant medications. A 28-year-old man with history of 13/14-chromosomal translocation presented with fevers, vomiting, and jaundice. Aspartate-aminotransferase and alanine-aminotransferase levels peaked above 20,000 IU/L and 5,000 IU/L, respectively. He developed coagulopathy but without altered mental status. Patient reported taking up to 400 mg diphenhydramine nightly, without concomitant acetaminophen, for insomnia. He denied taking other medications, supplements, antibiotics, and herbals. A thorough workup of liver injury ruled out viral hepatitis (including A, B, C, and E, autoimmune, toxic, ischemic, and metabolic etiologies including Wilson’s disease. A liver biopsy was consistent with DILI without evidence of iron or copper deposition. Diphenhydramine was determined to be the likely culprit. This is the first reported case of diphenhydramine-induced liver injury without concomitant use of acetaminophen.

LIVER AND BONE MARROW STEM/PROGENITOR CELLS AS REGULATORS OF REPARATIVE REGENERATION OF DAMAGED LIVER

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А. V. Lundup

2010-01-01

Full Text Available In this review the modern information about effectiveness of liver insufficiency treatment by stem/ progenitor cells of liver (oval cells and bone marrow (hemopoietic cells and mesenchymal cells was presented. It is shown that medical action of these cells is referred on normalization of liver cell interaction and reorganization of processes of a reparative regeneration in damaged liver. It is believed that application of mesenchymal stromal cells from an autological bone marrow is the most perspective strategy. However, for definitive judgement about regenerative possibilities of the autological bone marrow cells it is necessary to carry out large-scale double blind clinical researches. 

Non-invasive evaluation of liver stiffness after splenectomy in rabbits with CCl4-induced liver fibrosis.

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Wang, Ming-Jun; Ling, Wen-Wu; Wang, Hong; Meng, Ling-Wei; Cai, He; Peng, Bing

2016-12-14

To investigate the diagnostic performance of liver stiffness measurement (LSM) by elastography point quantification (ElastPQ) in animal models and determine the longitudinal changes in liver stiffness by ElastPQ after splenectomy at different stages of fibrosis. Liver stiffness was measured in sixty-eight rabbits with CCl 4 -induced liver fibrosis at different stages and eight healthy control rabbits by ElastPQ. Liver biopsies and blood samples were obtained at scheduled time points to assess liver function and degree of fibrosis. Thirty-one rabbits with complete data that underwent splenectomy at different stages of liver fibrosis were then included for dynamic monitoring of changes in liver stiffness by ElastPQ and liver function according to blood tests. LSM by ElastPQ was significantly correlated with histologic fibrosis stage ( r = 0.85, P fibrosis, moderate fibrosis, and cirrhosis, respectively. Longitudinal monitoring of the changes in liver stiffness by ElastPQ showed that early splenectomy (especially F1) may delay liver fibrosis progression. ElastPQ is an available, convenient, objective and non-invasive technique for assessing liver stiffness in rabbits with CCl 4 -induced liver fibrosis. In addition, liver stiffness measurements using ElastPQ can dynamically monitor the changes in liver stiffness in rabbit models, and in patients, after splenectomy.

Induction of Foxp3-expressing regulatory T-cells by donor blood transfusion is required for tolerance to rat liver allografts.

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Yuta Abe

Full Text Available BACKGROUND: Donor-specific blood transfusion (DST prior to solid organ transplantation has been shown to induce long-term allograft survival in the absence of immunosuppressive therapy. Although the mechanisms underlying DST-induced allograft tolerance are not well defined, there is evidence to suggest DST induces one or more populations of antigen-specific regulatory cells that suppress allograft rejection. However, neither the identity nor the regulatory properties of these tolerogenic lymphocytes have been reported. Therefore, the objective of this study was to define the kinetics, phenotype and suppressive function of the regulatory cells induced by DST alone or in combination with liver allograft transplantation (LTx. METHODOLOGY/PRINCIPAL FINDINGS: Tolerance to Dark Agouti (DA; RT1(a rat liver allografts was induced by injection (iv of 1 ml of heparinized DA blood to naïve Lewis (LEW; RT1(l rats once per week for 4 weeks prior to LTx. We found that preoperative DST alone generates CD4(+ T-cells that when transferred into naïve LEW recipients are capable of suppressing DA liver allograft rejection and promoting long-term survival of the graft and recipient. However, these DST-generated T-cells did not express the regulatory T-cell (Treg transcription factor Foxp3 nor did they suppress alloantigen (DA-induced activation of LEW T-cells in vitro suggesting that these lymphocytes are not fully functional regulatory Tregs. We did observe that DST+LTx (but not DST alone induced the time-dependent formation of CD4(+Foxp3(+ Tregs that potently suppressed alloantigen-induced activation of naïve LEW T-cells in vitro and liver allograft rejection in vivo. Finally, we present data demonstrating that virtually all of the Foxp3-expressing Tregs reside within the CD4(+CD45RC(- population whereas in which approximately 50% of these Tregs express CD25. CONCLUSIONS/SIGNIFICANCE: We conclude that preoperative DST, in the absence of liver allograft

Analysis of the apoptosis of brain and liver cells induced by ionizing radiation

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Konoplya, E.F.; Litvinchuk, A.V.; Zajtseva, O.A.; Stashkevich, D.G.

2010-01-01

The PCR-analysis of the expression of two oncogenes (bax/bcl-2) in the liver and brain tissues of the animals after being exposed to gamma-rays at doses of 1,0 and 4,0 Gy at remote terms after the action of (30, 60, 90 days) was made. The proofs of start-up of the genetic program of apoptosis of brain and liver cells were obtained. This can be a reason for functional dysfunction of a particular organ and the whole organism. (authors)

Perfluoroalkyl acids-induced liver steatosis: Effects on genes controlling lipid homeostasis

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Das, Kaberi P.; Wood, Carmen R.; Lin, Mimi T.; Starkov, Anatoly A.; Lau, Christopher; Wallace, Kendall B.; Corton, J. Christopher; Abbott, Barbara D.

2017-01-01

Highlights: • Structurally diverse PFAAs induced fatty liver and increased TG accumulation in mouse. • Genes of lipid synthesis and degradation were increased after exposure to PFAAs. • PFAAs did not inhibit either mitochondrial fatty acid transport or β-oxidation directly. - Abstract: Persistent presence of perfluoroalkyl acids (PFAAs) in the environment is due to their extensive use in industrial and consumer products, and their slow decay. Biochemical tests in rodent demonstrated that these chemicals are potent modifiers of lipid metabolism and cause hepatocellular steatosis. However, the molecular mechanism of PFAAs interference with lipid metabolism remains to be elucidated. Currently, two major hypotheses are that PFAAs interfere with mitochondrial beta-oxidation of fatty acids and/or they affect the transcriptional activity of peroxisome proliferator-activated receptor α (PPARα) in liver. To determine the ability of structurally-diverse PFAAs to cause steatosis, as well as to understand the underlying molecular mechanisms, wild-type (WT) and PPARα-null mice were treated with perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), or perfluorohexane sulfonate (PFHxS), by oral gavage for 7 days, and their effects were compared to that of PPARα agonist WY-14643 (WY), which does not cause steatosis. Increases in liver weight and cell size, and decreases in DNA content per mg of liver, were observed for all compounds in WT mice, and were also seen in PPARα-null mice for PFOA, PFNA, and PFHxS, but not for WY. In Oil Red O stained sections, WT liver showed increased lipid accumulation in all treatment groups, whereas in PPARα-null livers, accumulation was observed after PFNA and PFHxS treatment, adding to the burden of steatosis observed in control (untreated) PPARα-null mice. Liver triglyceride (TG) levels were elevated in WT mice by all PFAAs and in PPARα-null mice only by PFNA. In vitro β-oxidation of palmitoyl carnitine by isolated rat

Impairment of Akt activity by CYP2E1 mediated oxidative stress is involved in chronic ethanol-induced fatty liver

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Tao Zeng

2018-04-01

Full Text Available Protein kinase B (PKB/Akt plays important roles in the regulation of lipid homeostasis, and impairment of Akt activity has been demonstrated to be involved in the development of non-alcoholic fatty liver disease (NAFLD. Previous studies suggest that cytochrome P4502E1 (CYP2E1 plays causal roles in the pathogenesis of alcoholic fatty liver (AFL. We hypothesized that Akt activity might be impaired due to CYP2E1-induced oxidative stress in chronic ethanol-induced hepatic steatosis. In this study, we found that chronic ethanol-induced hepatic steatosis was accompanied with reduced phosphorylation of Akt at Thr308 in mice liver. Chronic ethanol exposure had no effects on the protein levels of phosphatidylinositol 3 kinase (PI3K and phosphatase and tensin homologue deleted on chromosome ten (PTEN, and led to a slight decrease of phosphoinositide-dependent protein kinase 1 (PDK-1 protein level. Ethanol exposure resulted in increased levels of malondialdehyde (MDA and 4-hydroxynonenal (4-HNE-Akt adducts, which was significantly inhibited by chlormethiazole (CMZ, an efficient CYP2E1 inhibitor. Interestingly, N-acetyl-L-cysteine (NAC significantly attenuated chronic ethanol-induced hepatic fat accumulation and the decline of Akt phosphorylation at Thr308. In the in vitro studies, Akt phosphorylation was suppressed in CYP2E1-expressing HepG2 (CYP2E1-HepG2 cells compared with the negative control HepG2 (NC-HepG2 cells, and 4-HNE treatment led to significant decrease of Akt phosphorylation at Thr308 in wild type HepG2 cells. Lastly, pharmacological activation of Akt by insulin-like growth factor-1 (IGF-1 significantly alleviated chronic ethanol-induced fatty liver in mice. Collectively, these results indicate that CYP2E1-induced oxidative stress may be responsible for ethanol-induced suppression of Akt phosphorylation and pharmacological modulation of Akt in liver may be an effective strategy for the treatment of ethanol-induced fatty liver. Keywords

Impaired methylation as a novel mechanism for proteasome suppression in liver cells

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Osna, Natalia A., E-mail: nosna@UNMC.edu [Liver Study Unit, The Omaha Veterans Affairs VA Medical Center, Omaha, NE 68105 (United States); Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68105 (United States); White, Ronda L.; Donohue, Terrence M. [Liver Study Unit, The Omaha Veterans Affairs VA Medical Center, Omaha, NE 68105 (United States); Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68105 (United States); Beard, Michael R. [Department of Molecular Biosciences, University of Adelaide (Australia); Tuma, Dean J.; Kharbanda, Kusum K. [Liver Study Unit, The Omaha Veterans Affairs VA Medical Center, Omaha, NE 68105 (United States); Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68105 (United States)

2010-01-08

The proteasome is a multi-catalytic protein degradation enzyme that is regulated by ethanol-induced oxidative stress; such suppression is attributed to CYP2E1-generated metabolites. However, under certain conditions, it appears that in addition to oxidative stress, other mechanisms are also involved in proteasome regulation. This study investigated whether impaired protein methylation that occurs during exposure of liver cells to ethanol, may contribute to suppression of proteasome activity. We measured the chymotrypsin-like proteasome activity in Huh7CYP cells, hepatocytes, liver cytosols and nuclear extracts or purified 20S proteasome under conditions that maintain or prevent protein methylation. Reduction of proteasome activity of hepatoma cell and hepatocytes by ethanol or tubercidin was prevented by simultaneous treatment with S-adenosylmethionine (SAM). Moreover, the tubercidin-induced decline in proteasome activity occurred in both nuclear and cytosolic fractions. In vitro exposure of cell cytosolic fractions or highly purified 20S proteasome to low SAM:S-adenosylhomocysteine (SAH) ratios in the buffer also suppressed proteasome function, indicating that one or more methyltransferase(s) may be associated with proteasomal subunits. Immunoblotting a purified 20S rabbit red cell proteasome preparation using methyl lysine-specific antibodies revealed a 25 kDa proteasome subunit that showed positive reactivity with anti-methyl lysine. This reactivity was modified when 20S proteasome was exposed to differential SAM:SAH ratios. We conclude that impaired methylation of proteasome subunits suppressed proteasome activity in liver cells indicating an additional, yet novel mechanism of proteasome activity regulation by ethanol.

Vitamin K1 attenuates bile duct ligation-induced liver fibrosis in rats.

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Jiao, Kun; Sun, Quan; Chen, Baian; Li, Shengli; Lu, Jing

2014-06-01

Vitamin K1 is used as a liver protection drug for cholestasis-induced liver fibrosis in China, but the mechanism of vitamin K1's action in liver fibrosis is unclear. In this study, a model of liver fibrosis was achieved via bile duct ligation in rats. The rats were then injected with vitamin K1, and the levels of serum aspartate aminotransferase, alanine transaminase, total bilirubin and the fibrotic grade score, collagen content, the expressions of α-smooth muscle actin (SMA) and cytokeratin 19 (CK19) were measured on day 28 after ligation. The levels of the biochemical parameters, fibrotic score and collagen content were significantly reduced by treatment with vitamin K1 in bile duct-ligated rats. In addition, α-SMA and CK19 expression was significantly reduced by vitamin K1 treatment in bile duct-ligated rats. These results suggested that vitamin K1 may attenuate liver fibrosis by inhibiting hepatic stellate cell activation in bile duct-ligated rats.

Methionine sulfoxide reductase A deficiency exacerbates acute liver injury induced by acetaminophen

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Singh, Mahendra Pratap; Kim, Ki Young; Kim, Hwa-Young

2017-01-01

Acetaminophen (APAP) overdose induces acute liver injury via enhanced oxidative stress and glutathione (GSH) depletion. Methionine sulfoxide reductase A (MsrA) acts as a reactive oxygen species scavenger by catalyzing the cyclic reduction of methionine-S-sulfoxide. Herein, we investigated the protective role of MsrA against APAP-induced liver damage using MsrA gene-deleted mice (MsrA −/− ). We found that MsrA −/− mice were more susceptible to APAP-induced acute liver injury than wild-type mice (MsrA +/+ ). The central lobule area of the MsrA −/− liver was more impaired with necrotic lesions. Serum alanine transaminase, aspartate transaminase, and lactate dehydrogenase levels were significantly higher in MsrA −/− than in MsrA +/+ mice after APAP challenge. Deletion of MsrA enhanced APAP-induced hepatic GSH depletion and oxidative stress, leading to increased susceptibility to APAP-induced liver injury in MsrA-deficient mice. APAP challenge increased Nrf2 activation more profoundly in MsrA −/− than in MsrA +/+ livers. Expression and nuclear accumulation of Nrf2 and its target gene expression were significantly elevated in MsrA −/− than in MsrA +/+ livers after APAP challenge. Taken together, our results demonstrate that MsrA protects the liver from APAP-induced toxicity. The data provided herein constitute the first in vivo evidence of the involvement of MsrA in hepatic function under APAP challenge. - Highlights: • MsrA deficiency increases APAP-induced liver damage. • MsrA deletion enhances APAP-induced hepatic GSH depletion and oxidative stress. • MsrA deficiency induces more profound activation of Nrf2 in response to APAP. • MsrA protects the liver from APAP-induced toxicity.

Exogenous normal lymph reduces liver injury induced by lipopolysaccharides in rats

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Zhao, Z.G.; Zhang, L.L.; Niu, C.Y.; Zhang, J.

2014-01-01

The liver is one of the target organs damaged by septic shock, wherein the spread of endotoxins begins. This study aimed to investigate the effects of exogenous normal lymph (ENL) on lipopolysaccharide (LPS)-induced liver injury in rats. Male Wistar rats were randomly divided into sham, LPS, and LPS+ENL groups. LPS (15 mg/kg) was administered intravenously via the left jugular vein to the LPS and LPS+ENL groups. At 15 min after the LPS injection, saline or ENL without cell components (5 mL/kg) was administered to the LPS and LPS+ENL groups, respectively, at a rate of 0.5 mL/min. Hepatocellular injury indices and hepatic histomorphology, as well as levels of P-selectin, intercellular adhesion molecule 1 (ICAM-1), myeloperoxidase (MPO), and Na + -K + -ATPase, were assessed in hepatic tissues. Liver tissue damage occurred after LPS injection. All levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in plasma as well as the wet/dry weight ratio of hepatic tissue in plasma increased. Similarly, P-selectin, ICAM-1, and MPO levels in hepatic tissues were elevated, whereas Na + -K + -ATPase activity in hepatocytes decreased. ENL treatment lessened hepatic tissue damage and decreased levels of AST, ALT, ICAM-1, and MPO. Meanwhile, the treatment increased the activity of Na + -K + -ATPase. These results indicated that ENL could alleviate LPS-induced liver injury, thereby suggesting an alternative therapeutic strategy for the treatment of liver injury accompanied by severe infection or sepsis

Patients with the worst outcomes after paracetamol (acetaminophen)-induced liver failure have an early monocytopenia.

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Moore, J K; MacKinnon, A C; Man, T Y; Manning, J R; Forbes, S J; Simpson, K J

2017-02-01

Acute liver failure (ALF) is associated with significant morbidity and mortality. Studies have implicated the immune response, especially monocyte/macrophages as being important in dictating outcome. To investigate changes in the circulating monocytes and other immune cells serially in patients with ALF, relate these with cytokine concentrations, monocyte gene expression and patient outcome. In a prospective case-control study in the Scottish Liver Transplant Unit, Royal Infirmary Edinburgh, 35 consecutive patients admitted with paracetamol-induced liver failure (POD-ALF), 10 patients with non-paracetamol causes of ALF and 16 controls were recruited. The peripheral blood monocyte phenotype was analysed by flow cytometry, circulating cytokines quantified by protein array and monocyte gene expression array performed and related to outcome. On admission, patients with worst outcomes after POD-ALF had a significant monocytopenia, characterised by reduced classical and expanded intermediate monocyte population. This was associated with reduced circulating lymphocytes and natural killer cells, peripheral cytokine patterns suggestive of a 'cytokine storm' and increased concentrations of cytokines associated with monocyte egress from the bone marrow. Gene expression array did not differentiate patient outcome. At day 4, there was no significant difference in monocyte, lymphocyte or natural killer cells between survivors and the patients with adverse outcomes. Severe paracetamol liver failure is associated with profound changes in the peripheral blood compartment, particularly in monocytes, related with worse outcomes. This is not seen in patients with non-paracetamol-induced liver failure. Significant monocytopenia on admission may allow earlier clarification of prognosis, and it highlights a potential target for therapeutic intervention. © 2016 John Wiley & Sons Ltd.

OPD4-positive T-cell lymphoma of the liver in systemic lupus erythematosus.

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Tsutsumi, Y; Deng, Y L; Uchiyama, M; Kawano, K; Ikeda, Y

1991-11-01

Primary malignant lymphoma of the liver occupying the right lobe, 14 x 9 x 7 cm in size, developed in a 30-year-old man with a 4-year history of autoimmune hemolytic anemia. The diagnosis of systemic lupus erythematosus (SLE) accompanying thrombocytopenia had been made clinically 10 months earlier. The liver biopsy specimen revealed diffuse proliferation of large lymphoma cells expressing the activated helper/inducer T-cell phenotype (LCA+, UCHL1+, OPD4+, LN3+, MT1-, L26-, MB1-, Leu M1-, Ki-1-, KP1-). The lymphoma was successfully treated by chemotherapy and irradiation. Intractable thrombocytopenia provoked fatal esophageal hemorrhage. At autopsy, no lymphomatous lesion was identified, and the hepatic right lobe contained an encapsulated necrotic lesion without any viable tumor cells. The bone marrow revealed marked hyperplasia of erythroid and megakaryocytic series. Extramedullary hematopoiesis was demonstrated in the liver, spleen and lymph nodes. This is the second case of primary hepatic T-cell lymphoma associated with SLE.

Metabolically induced liver inflammation leads to NASH and differs from LPS- or IL-1β-induced chronic inflammation.

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Liang, Wen; Lindeman, Jan H; Menke, Aswin L; Koonen, Debby P; Morrison, Martine; Havekes, Louis M; van den Hoek, Anita M; Kleemann, Robert

2014-05-01

The nature of the chronic inflammatory component that drives the development of non-alcoholic steatohepatitis (NASH) is unclear and possible inflammatory triggers have not been investigated systematically. We examined the effect of non-metabolic triggers (lipopolysaccharide (LPS), interleukin-1β (IL-1β), administered by slow-release minipumps) and metabolic dietary triggers (carbohydrate, cholesterol) of inflammation on the progression of bland liver steatosis (BS) to NASH. Transgenic APOE3*Leiden.huCETP (APOE3L.CETP) mice fed a high-fat diet (HFD) developed BS after 10 weeks. Then, inflammatory triggers were superimposed or not (control) for six more weeks. Mouse livers were analyzed with particular emphasis on hallmarks of inflammation which were defined in human liver biopsies with and without NASH. Livers of HFD-treated control mice remained steatotic and did not progress to NASH. All four inflammatory triggers activated hepatic nuclear factor-κB (NF-κB) significantly and comparably (≥5-fold). However, HFD+LPS or HFD+IL-1β did not induce a NASH-like phenotype and caused intrahepatic accumulation of almost exclusively mononuclear cells. By contrast, mice treated with metabolic triggers developed NASH, characterized by enhanced steatosis, hepatocellular hypertrophy, and formation of mixed-type inflammatory foci containing myeloperoxidase-positive granulocytes (neutrophils) as well as mononuclear cells, essentially as observed in human NASH. Specific for the metabolic inducers was an activation of the proinflammatory transcription factor activator protein-1 (AP-1), neutrophil infiltration, and induction of risk factors associated with human NASH, that is, dyslipidemia (by cholesterol) and insulin resistance (by carbohydrate). In conclusion, HFD feeding followed by NF-κB activation per se (LPS, IL-1β) does not promote the transition from BS to NASH. HFD feeding followed by metabolically evoked inflammation induces additional inflammatory components

Extracellular Vesicles from Human Liver Stem Cells Reduce Injury in an Ex Vivo Normothermic Hypoxic Rat Liver Perfusion Model.

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Rigo, Federica; De Stefano, Nicola; Navarro-Tableros, Victor; David, Ezio; Rizza, Giorgia; Catalano, Giorgia; Gilbo, Nicholas; Maione, Francesca; Gonella, Federica; Roggio, Dorotea; Martini, Silvia; Patrono, Damiano; Salizzoni, Mauro; Camussi, Giovanni; Romagnoli, Renato

2018-05-01

The gold standard for organ preservation before transplantation is static cold storage, which is unable to fully protect suboptimal livers from ischemia/reperfusion injury. An emerging alternative is normothermic machine perfusion (NMP), which permits organ reconditioning. Here, we aimed to explore the feasibility of a pharmacological intervention on isolated rat livers by using a combination of NMP and human liver stem cells-derived extracellular vesicles (HLSC-EV). We established an ex vivo murine model of NMP capable to maintain liver function despite an ongoing hypoxic injury induced by hemodilution. Livers were perfused for 4 hours without (control group, n = 10) or with HLSC-EV (treated group, n = 9). Bile production was quantified; perfusate samples were collected hourly to measure metabolic (pH, pO2, pCO2) and cytolysis parameters (AST, alanine aminotransferase, lactate dehydrogenase). At the end of perfusion, we assessed HLSC-EV engraftment by immunofluorescence, tissue injury by histology, apoptosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, tissue hypoxia-inducible factor 1-α, and transforming growth factor-beta 1 RNA expression by quantitative reverse transcription-polymerase chain reaction. During hypoxic NMP, livers were able to maintain homeostasis and produce bile. In the treated group, AST (P = 0.018) and lactate dehydrogenase (P = 0.032) levels were significantly lower than those of the control group at 3 hours of perfusion, and AST levels persisted lower at 4 hours (P = 0.003). By the end of NMP, HLSC-EV had been uptaken by hepatocytes, and EV treatment significantly reduced histological damage (P = 0.030), apoptosis (P = 0.049), and RNA overexpression of hypoxia-inducible factor 1-α (P < 0.0001) and transforming growth factor-beta 1 (P = 0.014). HLSC-EV treatment, even in a short-duration model, was feasible and effectively reduced liver injury during hypoxic NMP.

In vivo 19F-MRS observation of 5-FU metabolism in fatty liver induced by choline-deficient diet

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Otsuka, Hideki; Harada, Masafumi; Nishitani, Hiromu; Koga, Keiko.

1996-01-01

Using 19 F-MRS, 5-FU metabolism was investigated in rat fatty liver. Fatty liver was induced by choline-deficient diet (CD diet). This study showed differences in 5-FU metabolism between normal and fatty liver. After laparotomy, a surface coil was placed directly on the liver surface. Spectra were continuously obtained after injection of 5-FU 100 mg/kg body weight via a catheter inserted into femoral vein. We made MRI and 1 H-MRS study to examine the lipid accumulation. Histological study was also performed using HE (hematoxylin-eosin) and oil red stain. The livers of rats fed a CD diet showed very high intensity on T 1 -WI. 1 H-MRS was very useful in deteminating the fat content because the fat ratio demonstrated by 1 H-MRS is well correlated to histological findings. In 19 F-MRS, we recognized the following four peaks: 5-FU, FBAL, Fnct (fluoronucleotide) and FUPA. The decrease of 5-FU was not very apparent, but compared to the normal liver, the formation of Fnct increased and the formation of FBAL was suppressed in fatty liver. The rats fed a CD diet for four weeks showed a higher Fnct peak and lower FBAL peak compared with the results of rats fed a CD diet for two weeks. In a CD diet group, liver cell degeneration and necrotic changes were observed histologically. It is reported that cell degeneration is followed by cell proliferation in fatty liver induced by a choline deficient diet, and the high Fnct peak found in our study may reflect this phenomenon. The high Fnct peak on 19 F-MRS may correspond to recovering reaction from liver injury like fatty liver. (author)

Gene expression data from acetaminophen-induced toxicity in human hepatic in vitro systems and clinical liver samples

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Robim M. Rodrigues

2016-06-01

Full Text Available This data set is composed of transcriptomics analyses of (i liver samples from patients suffering from acetaminophen-induced acute liver failure (ALF and (ii hepatic cell systems exposed to acetaminophen and their respective controls. The in vitro systems include widely employed cell lines i.e. HepaRG and HepG2 cells as well as a novel stem cell-derived model i.e. human skin-precursors-derived hepatocyte-like cells (hSKP-HPC. Data from primary human hepatocytes was also added to the data set “Open TG-GATEs: a large-scale toxicogenomics database” (Igarashi et al., 2015 [1]. Changes in gene expression due to acetaminophen intoxication as well as comparative information between human in vivo and in vitro samples are provided. The microarray data have been deposited in NCBI׳s Gene Expression Omnibus and are accessible through GEO Series accession number GEO: GSE74000. The provided data is used to evaluate the predictive capacity of each hepatic in vitro system and can be directly compared with large-scale publically available toxicogenomics databases. Further interpretation and discussion of these data feature in the corresponding research article “Toxicogenomics-based prediction of acetaminophen-induced liver injury using human hepatic cell systems” (Rodrigues et al., 2016 [2].

Pivotal roles of Kupffer cells in the progression and regression of DDC-induced chronic cholangiopathy.

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Jemail, Leila; Miyao, Masashi; Kotani, Hirokazu; Kawai, Chihiro; Minami, Hirozo; Abiru, Hitoshi; Tamaki, Keiji

2018-04-23

Kupffer cells (KCs) are key players in maintaining tissue homeostasis and are involved in various liver diseases. However, the roles of KCs in the pathogenesis of cholangiopathy are largely unknown. We aimed to investigate the precise roles of KCs in both the progression and regression phases of the 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced cholangiopathy model. In the early phase of DDC-induced cholangiopathy, the number of KCs significantly increased over time. Moreover, KCs were associated with abnormal phenotypic changes in other liver cells, such as hepatocytes, biliary epithelial cells, liver sinusoidal endothelial cells, and hepatic stellate cells. In contrast, KC depletion by clodronate administration suppressed the progression of the disease, and maintained the phenotypes of other cells. In the regression phase, the numbers of KCs significantly decreased, and the cells redifferentiated to their quiescent state. In contrast, KC depletion delayed the recovery of cells by maintaining other liver cells in an active state. These findings suggest that KCs play detrimental roles in the progression phase; however, they are beneficial in the regression phase by mediating interactions between other liver cells. Our data provide new insights into the roles of KCs in the pathogenesis of cholangiopathy.

Activation of liver X receptors prevents statin-induced death of 3T3-L1 preadipocytes

DEFF Research Database (Denmark)

Madsen, Lise; Petersen, Rasmus K; Steffensen, Knut R

2008-01-01

The biological functions of liver X receptors (LXRs) alpha and beta have primarily been linked to pathways involved in fatty acid and cholesterol homeostasis. Here we report a novel role of LXR activation in protecting cells from statin-induced death. When 3T3-L1 preadipocytes were induced...

Therapeutic efficacy of human hepatocyte transplantation in a SCID/uPA mouse model with inducible liver disease.

Directory of Open Access Journals (Sweden)

Donna N Douglas

2010-02-01

Full Text Available Severe Combined Immune Deficient (SCID/Urokinase-type Plasminogen Activator (uPA mice undergo liver failure and are useful hosts for the propagation of transplanted human hepatocytes (HH which must compete with recipient-derived hepatocytes for replacement of the diseased liver parenchyma. While partial replacement by HH has proven useful for studies with Hepatitis C virus, complete replacement of SCID/uPA mouse liver by HH has never been achieved and limits the broader application of these mice for other areas of biomedical research. The herpes simplex virus type-1 thymidine kinase (HSVtk/ganciclovir (GCV system is a powerful tool for cell-specific ablation in transgenic animals. The aim of this study was to selectively eliminate murine-derived parenchymal liver cells from humanized SCID/uPA mouse liver in order to achieve mice with completely humanized liver parenchyma. Thus, we reproduced the HSVtk (vTK/GCV system of hepatic failure in SCID/uPA mice.In vitro experiments demonstrated efficient killing of vTK expressing hepatoma cells after GCV treatment. For in vivo experiments, expression of vTK was targeted to the livers of FVB/N and SCID/uPA mice. Hepatic sensitivity to GCV was first established in FVB/N mice since these mice do not undergo liver failure inherent to SCID/uPA mice. Hepatic vTK expression was found to be an integral component of GCV-induced pathologic and biochemical alterations and caused death due to liver dysfunction in vTK transgenic FVB/N and non-transplanted SCID/uPA mice. In SCID/uPA mice with humanized liver, vTK/GCV caused death despite extensive replacement of the mouse liver parenchyma with HH (ranging from 32-87%. Surprisingly, vTK/GCV-dependent apoptosis and mitochondrial aberrations were also localized to bystander vTK-negative HH.Extensive replacement of mouse liver parenchyma by HH does not provide a secure therapeutic advantage against vTK/GCV-induced cytotoxicity targeted to residual mouse hepatocytes

Imatinib-induced fulminant liver failure in chronic myeloid leukemia: role of liver transplant and second-generation tyrosine kinase inhibitors: a case report.

Science.gov (United States)

Nacif, Lucas Souto; Waisberg, Daniel R; Pinheiro, Rafael Soares; Lima, Fabiana Roberto; Rocha-Santos, Vinicius; Andraus, Wellington; D'Albuquerque, Luiz Carneiro

2018-03-10

There is a worldwide problem of acute liver failure and mortality associated with remaining on the waiting for a liver transplant. In this study, we highlight results published in recent years by leading transplant centers in evaluating imatinib-induced acute liver failure in chronic myeloid leukemia and follow-up in liver transplantation. A 36-year-old brown-skinned woman (mixed Brazilian race) diagnosed 1 year earlier with chronic myeloid leukemia was started after delivery of a baby and continued for 6 months with imatinib mesylate (selective inhibitor of Bcr-Abl tyrosine kinase), which induced liver failure. We conducted a literature review using the PubMed database for articles published through September 2017, and we demonstrate a role of liver transplant in this situation for imatinib-induced liver failure. We report previously published results and a successful liver transplant after acute liver failure due to imatinib-induced in chronic myeloid leukemia treatment. We report a case of a successful liver transplant after acute liver failure resulting from imatinib-induced chronic myeloid leukemia treatment. The literature reveals the importance of prompt acute liver failure diagnosis and treatment with liver transplant in selected cases.

The emerging role of mast cells in liver disease.

Science.gov (United States)

Jarido, Veronica; Kennedy, Lindsey; Hargrove, Laura; Demieville, Jennifer; Thomson, Joanne; Stephenson, Kristen; Francis, Heather

2017-08-01

The depth of our knowledge regarding mast cells has widened exponentially in the last 20 years. Once thought to be only important for allergy-mediated events, mast cells are now recognized to be important regulators of a number of pathological processes. The revelation that mast cells can influence organs, tissues, and cells has increased interest in mast cell research during liver disease. The purpose of this review is to refresh the reader's knowledge of the development, type, and location of mast cells and to review recent work that demonstrates the role of hepatic mast cells during diseased states. This review focuses primarily on liver diseases and mast cells during autoimmune disease, hepatitis, fatty liver disease, liver cancer, and aging in the liver. Overall, these studies demonstrate the potential role of mast cells in disease progression.

Obeticholic acid protects mice against lipopolysaccharide-induced liver injury and inflammation.

Science.gov (United States)

Xiong, Xi; Ren, Yuqian; Cui, Yun; Li, Rui; Wang, Chunxia; Zhang, Yucai

2017-12-01

Cholestasis, as a main manifestation, induces liver injury during sepsis. The farnesoid X receptor (FXR) plays an important role in regulating bile acid homeostasis. Whether FXR activation by its agonist obeticholic acid (OCA) is contributed to improve sepsis-induced liver injury remains unknown. The aim of the present study was to investigate the effect of OCA on lipopolysaccharide (LPS)-induced acute liver injury in mice. 8-week old male C57BL/6J mice were randomly divided into control group, LPS group, oral OCA group and LPS plus oral OCA (LPS + OCA) group. The serum and livers were collected for further analysis. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bile acid (TBA) and total bilirubin (TBIL) were measured at indicated time after LPS administration. Liver sections were stained with hematoxylin & eosin (H&E). Orally OCA pretreatment stimulated the expression of FXR and BSEP in livers and protected mice from LPS-induced hepatocyte apoptosis and inflammatory infiltration. Consistently, LPS-induced higher serum levels of ALT, AST, TBA and TBIL were significantly reversed by OCA administration. Meanwhile, the mRNA levels of interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α) and IL-6 were decreased in livers of mice in LPS + OCA group compared with LPS group. Further investigation indicated that the higher expression of ATF4 and LC3II/I were associated with the protective effect of OCA on LPS-induced liver injury. Orally OCA pretreatment protects mice from LPS-induced liver injury possibly contributed by improved bile acid homeostasis, decreased inflammatory factors and ATF4-mediated autophagy activity in hepatocytes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The potential of induced pluripotent stem cell derived hepatocytes.

Science.gov (United States)

Hannoun, Zara; Steichen, Clara; Dianat, Noushin; Weber, Anne; Dubart-Kupperschmitt, Anne

2016-07-01

Orthotopic liver transplantation remains the only curative treatment for liver disease. However, the number of patients who die while on the waiting list (15%) has increased in recent years as a result of severe organ shortages; furthermore the incidence of liver disease is increasing worldwide. Clinical trials involving hepatocyte transplantation have provided encouraging results. However, transplanted cell function appears to often decline after several months, necessitating liver transplantation. The precise aetiology of the loss of cell function is not clear, but poor engraftment and immune-mediated loss appear to be important factors. Also, primary human hepatocytes (PHH) are not readily available, de-differentiate, and die rapidly in culture. Hepatocytes are available from other sources, such as tumour-derived human hepatocyte cell lines and immortalised human hepatocyte cell lines or porcine hepatocytes. However, all these cells suffer from various limitations such as reduced or differences in functions or risk of zoonotic infections. Due to their significant potential, one possible inexhaustible source of hepatocytes is through the directed differentiation of human induced pluripotent stem cells (hiPSCs). This review will discuss the potential applications and existing limitations of hiPSC-derived hepatocytes in regenerative medicine, drug screening, in vitro disease modelling and bioartificial livers. Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Heavy metal-induced gene expression in fish and fish cell lines

International Nuclear Information System (INIS)

Price-Haughey, J.; Bonham, K.; Gedamu, L.

1986-01-01

Two isoforms of metallothionein (MT) have been isolated from rainbow trout livers following CdCl 2 injections. These MTs have been identified by standard procedures and appear to be similar to mammalian MTs. Total RNA from such induced livers was shown to contain high levels of MT-mRNA activity when translated in cell free systems. This activity was demonstrated to be in the 8 to 10S region of a sucrose gradient. The RNA fractions also showed homology to a mouse MT-I cDNA probe. The exposure of rainbow trout hepatoma (RTH) cells to various concentrations of CdCl 2 and ZnCl 2 induced the expression of MT and MT-mRNA. Exposure of Chinook salmon embryonic (CHSE) cells to these metals, however, did not result in MT synthesis, suggesting that the MT genes have not become committed to transcription. Instead, an unknown low molecular weight (MW = 14 kDa) protein was induced. This metal-inducible protein (MIP) was capable of binding 109 Cd and was stable to heating, while the binding of the metal to this protein was not. These characteristics have been reported for a protein induced in rainbow trout liver following environmental exposure to cadmium

Liver cell-targeted delivery of therapeutic molecules.

Science.gov (United States)

Kang, Jeong-Hun; Toita, Riki; Murata, Masaharu

2016-01-01

The liver is the largest internal organ in mammals and is involved in metabolism, detoxification, synthesis of proteins and lipids, secretion of cytokines and growth factors and immune/inflammatory responses. Hepatitis, alcoholic or non-alcoholic liver disease, hepatocellular carcinoma, hepatic veno-occlusive disease, and liver fibrosis and cirrhosis are the most common liver diseases. Safe and efficient delivery of therapeutic molecules (drugs, genes or proteins) into the liver is very important to increase the clinical efficacy of these molecules and to reduce their side effects in other organs. Several liver cell-targeted delivery systems have been developed and tested in vivo or ex vivo/in vitro. In this review, we discuss the literature concerning liver cell-targeted delivery systems, with a particular emphasis on the results of in vivo studies.

Loss of neutrophil polarization in colon carcinoma liver metastases of mice with an inducible, liver-specific IGF-I deficiency.

Science.gov (United States)

Rayes, Roni F; Milette, Simon; Fernandez, Maria Celia; Ham, Boram; Wang, Ni; Bourdeau, France; Perrino, Stephanie; Yakar, Shoshana; Brodt, Pnina

2018-03-20

The growth of cancer metastases in the liver depends on a permissive interaction with the hepatic microenvironment and neutrophils can contribute to this interaction, either positively or negatively, depending on their phenotype. Here we investigated the role of IGF-I in the control of the tumor microenvironment in the liver, using mice with a conditional, liver-specific, IGF-I deficiency (iLID) induced by a single tamoxifen injection. In mice that had a sustained (3 weeks) IGF-I deficiency prior to the intrasplenic/portal inoculation of colon carcinoma MC-38 cells, we observed an increase in neutrophil accumulation in the liver relative to controls. However, unlike controls, these neutrophils did not acquire the (anti-inflammatory) tumor-promoting phenotype, as evidenced by retention of high ICAM-1 expression and nitric oxide production and low CXCR4, CCL5, and VEGF expression and arginase production, all characteristic of the (pro-inflammatory) phenotype. This coincided with an increase in apoptotic tumor cells and reduced metastasis. Neutrophils isolated from these mice also had reduced IGF-IR expression levels. These changes were not observed in iLID mice with a short-term (2 days) IGF-I depletion, despite a 70% reduction in their circulating IGF-I levels, indicating that a sustained IGF-I deficiency was necessary to alter the neutrophil phenotype. Similar results were obtained with the highly metastatic Lewis lung carcinoma subline H-59 cells and in mice injected with an IGF-Trap that blocks IGF-IR signaling by reducing ligand bioavailability. Our results implicate the IGF axis in neutrophil polarization and the induction of a pro-metastatic microenvironment in the liver.

The relationship between radiation-induced apoptosis and the expression of cytokines in the rat's liver

International Nuclear Information System (INIS)

An, Eun Joo; Lee, Kyung Ja; Rhee, Chung Sik

2000-01-01

To determine the role of cytokines in the apoptosis of rat's liver following irradiation. Sprague-Dawley rats were irradiated to entire body with a single dose of 8 Gy. The rats were divided into 5 groups according to the sacrifice day after irradiation. The liver and blood after 1, 3, 5, 7, and 14 days irradiation were sampled for evaluation of mechanism of apoptosis and role of cytokine in relation to radiation-induced tissue damage. The study was composed of microscopic evaluation of liver tissue, in situ detection method for apoptosis, immunohistochemical stain of IL-1, IL-4, IL-6 and TNF, bioassay and radioimmunoassay of IL-6 in liver tissue and blood. Radiation-induced liver damage was noted from first day of radiation, and most severe parenchymal damage associated with infiltration of chronic inflammatory cells was seen in the groups of 5 days after radiation. A number of apoptosis were observed 1 day after radiation on both light microscope and in situ method. Afterwards, the number of apoptosis was gradually diminished. On immunohistochemical study, IL-1 and TNF were expressed 1, 3 days after radiation, but not expressed after that. IL-4 was not expressed in the entire groups. IL-6 was expressed with strong positivity in 1, 3 days after radiation. Bioassay and RIA of IL-6 in liver tissue and blood showed the highest value in 1 day after radiation, and the value is diminished after then. Apoptosis seemed to be the important mechanism of radiation-induced liver damage, and is possibly induced by the release of cytokines, such as IL-1, IL-6, TNF in view the simultaneously increased appearance of apoptosis and cytokines

Hepatoprotective Effect of Opuntia robusta and Opuntia streptacantha Fruits against Acetaminophen-Induced Acute Liver Damage

Directory of Open Access Journals (Sweden)

Herson Antonio González-Ponce

2016-10-01

Full Text Available Acetaminophen (APAP-induced acute liver failure (ALF is a serious health problem in developed countries. N-acetyl-L-cysteine (NAC, the current therapy for APAP-induced ALF, is not always effective, and liver transplantation is often needed. Opuntia spp. fruits are an important source of nutrients and contain high levels of bioactive compounds, including antioxidants. The aim of this study was to evaluate the hepatoprotective effect of Opuntia robusta and Opuntia streptacantha extracts against APAP-induced ALF. In addition, we analyzed the antioxidant activities of these extracts. Fruit extracts (800mg/kg/day, orally were given prophylactically to male Wistar rats before intoxication with APAP (500 mg/kg, intraperitoneally. Rat hepatocyte cultures were exposed to 20mmol/LAPAP, and necrosis was assessed by LDH leakage. Opuntia robusta had significantly higher levels of antioxidants than Opuntia streptacantha. Both extracts significantly attenuated APAP-induced injury markers AST, ALT and ALP and improved liver histology. The Opuntia extracts reversed APAP-induced depletion of liver GSH and glycogen stores. In cultured hepatocytes, Opuntia extracts significantly reduced leakage of LDH and cell necrosis, both prophylactically and therapeutically. Both extracts appeared to be superior to NAC when used therapeutically. We conclude that Opuntia extracts are hepatoprotective and can be used as a nutraceutical to prevent ALF.

Liver involvement in Langerhans cell histiocytosis

International Nuclear Information System (INIS)

Wong, Adelaine; Ortiz-Neira, Clara L.; Abou Reslan, Walid; Kaura, Deepak; Sharon, Raphael; Anderson, Ronald; Pinto-Rojas, Alfredo

2006-01-01

Liver involvement in Langerhans cell histiocytosis (LCH) typically presents with hepatomegaly and other signs of liver dysfunction. We present an 11-month-old child having only minimally elevated liver enzymes as an indication of liver involvement. Using sonography as the initial diagnostic tool followed by MRI, LCH of the liver was revealed. A review of sonographic, CT, MRI and MR cholangiopancreatography findings in liver LCH is presented. We recommend that physicians consider sonography and MRI screening for liver involvement in patients with newly diagnosed LCH, as periportal involvement may be present with little or no liver function abnormality present, as in this patient. (orig.)

Substance P increases liver fibrosis by differential changes in senescence of cholangiocytes and hepatic stellate cells.

Science.gov (United States)

Wan, Ying; Meng, Fanyin; Wu, Nan; Zhou, Tianhao; Venter, Julie; Francis, Heather; Kennedy, Lindsey; Glaser, Trenton; Bernuzzi, Francesca; Invernizzi, Pietro; Glaser, Shannon; Huang, Qiaobing; Alpini, Gianfranco

2017-08-01

Substance P (SP) is involved in the proliferation of cholangiocytes in bile duct-ligated (BDL) mice and human cholangiocarcinoma growth by interacting with the neurokinin-1 receptor (NK-1R). To identify whether SP regulates liver fibrosis during cholestasis, wild-type or NK-1R knockout (NK-1R -/- ) mice that received BDL or sham surgery and multidrug resistance protein 2 knockout (Mdr2 -/- ) mice treated with either an NK-1R antagonist (L-733,060) or saline were used. Additionally, wild-type mice were treated with SP or saline intraperitoneally. In vivo, there was increased expression of tachykinin precursor 1 (coding SP) and NK-1R in both BDL and Mdr2 -/- mice compared to wild-type mice. Expression of tachykinin precursor 1 and NK-1R was significantly higher in liver samples from primary sclerosing cholangitis patients compared to healthy controls. Knockout of NK-1R decreased BDL-induced liver fibrosis, and treatment with L-733,060 resulted in decreased liver fibrosis in Mdr2 -/- mice, which was shown by decreased sirius red staining, fibrosis gene and protein expression, and reduced transforming growth factor-β1 levels in serum and cholangiocyte supernatants. Furthermore, we observed that reduced liver fibrosis in NK-1R -/- mice with BDL surgery or Mdr2 -/- mice treated with L-733,060 was associated with enhanced cellular senescence of hepatic stellate cells and decreased senescence of cholangiocytes. In vitro, L-733,060 inhibited SP-induced expression of fibrotic genes in hepatic stellate cells and cholangiocytes; treatment with L-733,060 partially reversed the SP-induced decrease of senescence gene expression in cultured hepatic stellate cells and the SP-induced increase of senescence-related gene expression in cultured cholangiocytes. Collectively, our results demonstrate the regulatory effects of the SP/NK-1R axis on liver fibrosis through changes in cellular senescence during cholestatic liver injury. (Hepatology 2017;66:528-541). © 2017 by the American

Cell Patterning for Liver Tissue Engineering via Dielectrophoretic Mechanisms

Directory of Open Access Journals (Sweden)

Wan Nurlina Wan Yahya

2014-07-01

Full Text Available Liver transplantation is the most common treatment for patients with end-stage liver failure. However, liver transplantation is greatly limited by a shortage of donors. Liver tissue engineering may offer an alternative by providing an implantable engineered liver. Currently, diverse types of engineering approaches for in vitro liver cell culture are available, including scaffold-based methods, microfluidic platforms, and micropatterning techniques. Active cell patterning via dielectrophoretic (DEP force showed some advantages over other methods, including high speed, ease of handling, high precision and being label-free. This article summarizes liver function and regenerative mechanisms for better understanding in developing engineered liver. We then review recent advances in liver tissue engineering techniques and focus on DEP-based cell patterning, including microelectrode design and patterning configuration.

A cellular model to study drug-induced liver injury in nonalcoholic fatty liver disease: Application to acetaminophen

Energy Technology Data Exchange (ETDEWEB)

Michaut, Anaïs; Le Guillou, Dounia [INSERM, U991, Université de Rennes 1, Rennes (France); Moreau, Caroline [INSERM, U991, Université de Rennes 1, Rennes (France); Service de Biochimie et Toxicologie, CHU Pontchaillou, Rennes (France); Bucher, Simon [INSERM, U991, Université de Rennes 1, Rennes (France); McGill, Mitchell R. [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Martinais, Sophie [INSERM, U991, Université de Rennes 1, Rennes (France); Gicquel, Thomas; Morel, Isabelle [INSERM, U991, Université de Rennes 1, Rennes (France); Service de Biochimie et Toxicologie, CHU Pontchaillou, Rennes (France); Robin, Marie-Anne [INSERM, U991, Université de Rennes 1, Rennes (France); Jaeschke, Hartmut [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Fromenty, Bernard, E-mail: bernard.fromenty@inserm.fr [INSERM, U991, Université de Rennes 1, Rennes (France)

2016-02-01

Obesity and nonalcoholic fatty liver disease (NAFLD) can increase susceptibility to hepatotoxicity induced by some xenobiotics including drugs, but the involved mechanisms are poorly understood. For acetaminophen (APAP), a role of hepatic cytochrome P450 2E1 (CYP2E1) is suspected since the activity of this enzyme is consistently enhanced during NAFLD. The first aim of our study was to set up a cellular model of NAFLD characterized not only by triglyceride accumulation but also by higher CYP2E1 activity. To this end, human HepaRG cells were incubated for one week with stearic acid or oleic acid, in the presence of different concentrations of insulin. Although cellular triglycerides and the expression of lipid-responsive genes were similar with both fatty acids, CYP2E1 activity was significantly increased only by stearic acid. CYP2E1 activity was reduced by insulin and this effect was reproduced in cultured primary human hepatocytes. Next, APAP cytotoxicity was assessed in HepaRG cells with or without lipid accretion and CYP2E1 induction. Experiments with a large range of APAP concentrations showed that the loss of ATP and glutathione was almost always greater in the presence of stearic acid. In cells pretreated with the CYP2E1 inhibitor chlormethiazole, recovery of ATP was significantly higher in the presence of stearate with low (2.5 mM) or high (20 mM) concentrations of APAP. Levels of APAP-glucuronide were significantly enhanced by insulin. Hence, HepaRG cells can be used as a valuable model of NAFLD to unveil important metabolic and hormonal factors which can increase susceptibility to drug-induced hepatotoxicity. - Highlights: • Nonalcoholic fatty liver disease (NAFLD) is frequent in obese individuals. • NAFLD can favor hepatotoxicity induced by some drugs including acetaminophen (APAP). • A model of NAFLD was set up by using HepaRG cells incubated with stearate or oleate. • Stearate-loaded HepaRG cells presented higher cytochrome P450 2E1 (CYP2E1

Kinetics of liver macrophages (Kupffer cells) in SIV-infected macaques

International Nuclear Information System (INIS)

Ahsan, Muhammad H.; Gill, Amy F.; Alvarez, Xavier; Lackner, Andrew A.; Veazey, Ronald S.

2013-01-01

Since the liver drains antigens from the intestinal tract, and since the intestinal tract is a major site of viral replication, we examined the dynamics of liver macrophages (Kupffer cells) throughout SIV infection. Absolute numbers of Kupffer cells increased in the livers in acute infection, and in animals with AIDS. Significantly higher percentages of proliferating (BrdU+) Kupffer cells were detected in acute infection and in AIDS with similar trends in blood monocytes. Significantly higher percentages of apoptotic (AC3+) Kupffer cells were also found in acute and AIDS stages. However, productively infected cells were not detected in liver of 41/42 animals examined, despite abundant infected cells in gut and lymph nodes of all animals. Increased rates of Kupffer cell proliferation resulting in an increase in Kupffer cells without productive infection indicate SIV infection affects Kupffer cells, but the liver does not appear to be a major site of productive viral replication. - Highlights: • Kupffer cells increase in the liver of SIV-infected macaques. • Increased proliferation and apoptosis of Kupffer cells occurs in SIV infection. • Productively infected cells are rarely detected in the liver. • The liver is not a major site for SIV replication

Fraction from human and rat liver which is inhibitory for proliferation of liver cells.

Science.gov (United States)

Chen, T S; Ottenweller, J; Luke, A; Santos, S; Keeting, P; Cuy, R; Lea, M A

1989-01-01

A comparative study was undertaken with human and rat liver of a fraction reported to have growth inhibitory activity when prepared from rat liver. Fractions which were soluble in 70% ethanol and insoluble in 87% ethanol were prepared from liver cytosols. Electrophoretic analysis under denaturing conditions indicated that there were several quantitative or qualitative differences in the fractions from the two species. Fractions from both human and rat liver were found to be inhibitory for the incorporation of 3H-thymidine into DNA of foetal chick hepatocytes. Under conditions in which the rat fraction inhibited precursor incorporation into DNA of rat liver epithelial cells there was not a significant inhibitory effect with the fraction from human liver. DNA synthesis in a rat hepatoma cell line was not significantly inhibited by preparations from either species. The data suggested that corresponding fractions from both rat and human liver could have inhibitory effects on precursor incorporation into DNA but the magnitude of the effects and target cell specificity may differ.

A characterization of the ZFL cell line and primary hepatocytes as in vitro liver cell models for the zebrafish (Danio rerio)

International Nuclear Information System (INIS)

Eide, Marta; Rusten, Marte; Male, Rune; Jensen, Knut Helge Midtbø; Goksøyr, Anders

2014-01-01

Highlights: •The ZFL cell line and primary hepatocytes were characterized. •Basic and induced expression of nuclear receptors and target genes were found. •The ZFL cell line expresses very low basic levels of most genes. •The ZFL cells have low induction of gene expression following exposures. •Primary hepatocytes show large sex-dependent differences in gene expression. -- Abstract: The zebrafish (Danio rerio) is a widely used model species in biomedical research. The ZFL cell line, established from zebrafish liver, and freshly isolated primary hepatocytes from zebrafish have been used in several toxicological studies. However, no previous report has compared and characterized these two systems at the level of gene expression. The aim of this study was to evaluate the ZFL cell line in comparison to primary hepatocytes as in vitro models for studying effects of environmental contaminants in zebrafish liver. Using quantitative real-time PCR, the basal level and transcriptional induction potential of key genes involved in toxic responses in the ZFL cell line, primary hepatocytes and whole liver from zebrafish were compared. The study showed that the ZFL cells have lower levels of mRNA of most selected genes compared to zebrafish liver. The induced gene transcription following exposure to ligand was much lower in ZFL cells compared to zebrafish primary hepatocytes at the doses tested. Importantly, oestrogen receptor and vitellogenin genes showed low basal transcription and no induction response in the ZFL cell line. In conclusion, it appears that primary hepatocytes are well suited for studying environmental contaminants including xenoestrogens, but may show large sex-dependent differences in gene transcription. The ZFL cell line shows potential in toxicological studies involving the aryl hydrocarbon receptor pathway. However, low potential for transcriptional induction of genes in general should be expected, especially notable when studying estrogenic

A characterization of the ZFL cell line and primary hepatocytes as in vitro liver cell models for the zebrafish (Danio rerio)

Energy Technology Data Exchange (ETDEWEB)

Eide, Marta, E-mail: marta.eide@bio.uib.no [Department of Biology, University of Bergen, Bergen (Norway); Rusten, Marte; Male, Rune [Department of Molecular Biology, University of Bergen, Bergen (Norway); Jensen, Knut Helge Midtbø; Goksøyr, Anders [Department of Biology, University of Bergen, Bergen (Norway)

2014-02-15

Highlights: •The ZFL cell line and primary hepatocytes were characterized. •Basic and induced expression of nuclear receptors and target genes were found. •The ZFL cell line expresses very low basic levels of most genes. •The ZFL cells have low induction of gene expression following exposures. •Primary hepatocytes show large sex-dependent differences in gene expression. -- Abstract: The zebrafish (Danio rerio) is a widely used model species in biomedical research. The ZFL cell line, established from zebrafish liver, and freshly isolated primary hepatocytes from zebrafish have been used in several toxicological studies. However, no previous report has compared and characterized these two systems at the level of gene expression. The aim of this study was to evaluate the ZFL cell line in comparison to primary hepatocytes as in vitro models for studying effects of environmental contaminants in zebrafish liver. Using quantitative real-time PCR, the basal level and transcriptional induction potential of key genes involved in toxic responses in the ZFL cell line, primary hepatocytes and whole liver from zebrafish were compared. The study showed that the ZFL cells have lower levels of mRNA of most selected genes compared to zebrafish liver. The induced gene transcription following exposure to ligand was much lower in ZFL cells compared to zebrafish primary hepatocytes at the doses tested. Importantly, oestrogen receptor and vitellogenin genes showed low basal transcription and no induction response in the ZFL cell line. In conclusion, it appears that primary hepatocytes are well suited for studying environmental contaminants including xenoestrogens, but may show large sex-dependent differences in gene transcription. The ZFL cell line shows potential in toxicological studies involving the aryl hydrocarbon receptor pathway. However, low potential for transcriptional induction of genes in general should be expected, especially notable when studying estrogenic

New therapeutic strategies for canine liver disease; Growth factors and liver progenitor cells

NARCIS (Netherlands)

Arends, B.

2008-01-01

The liver has the unique capacity to regulate its mass after loss of functional liver cells due to liver disease, injury, and/or toxicity. Unfortunately, in the course of chronic liver disease this meticulously regulated regeneration process is imbalanced resulting in a decreased regenerative

Silymarin modulates doxorubicin-induced oxidative stress, Bcl-xL and p53 expression while preventing apoptotic and necrotic cell death in the liver

International Nuclear Information System (INIS)

Patel, Nirav; Joseph, Cecil; Corcoran, George B.; Ray, Sidhartha D.

2010-01-01

The emergence of silymarin (SMN) as a natural remedy for liver diseases, coupled with its entry into NIH clinical trial, signifies its hepatoprotective potential. SMN is noted for its ability to interfere with apoptotic signaling while acting as an antioxidant. This in vivo study was designed to explore the hepatotoxic potential of Doxorubicin (Dox), the well-known cardiotoxin, and in particular whether pre-exposures to SMN can prevent hepatotoxicity by reducing Dox-induced free radical mediated oxidative stress, by modulating expression of apoptotic signaling proteins like Bcl-xL, and by minimizing liver cell death occurring by apoptosis or necrosis. Groups of male ICR mice included Control, Dox alone, SMN alone, and Dox with SMN pre/co-treatment. Control and Dox groups received saline i.p. for 14 days. SMN was administered p.o. for 14 days at 16 mg/kg/day. An approximate LD 50 dose of Dox, 60 mg/kg, was administered i.p. on day 12 to animals receiving saline or SMN. Animals were euthanized 48 h later. Dox alone induced frank liver injury (> 50-fold increase in serum ALT) and oxidative stress (> 20-fold increase in malondialdehyde [MDA]), as well as direct damage to DNA (> 15-fold increase in DNA fragmentation). Coincident genomic damage and oxidative stress influenced genomic stability, reflected in increased PARP activity and p53 expression. Decreases in Bcl-xL protein coupled with enhanced accumulation of cytochrome c in the cytosol accompanied elevated indexes of apoptotic and necrotic cell death. Significantly, SMN exposure reduced Dox hepatotoxicity and associated apoptotic and necrotic cell death. The effects of SMN on Dox were broad, including the ability to modulate changes in both Bcl-xL and p53 expression. In animals treated with SMN, tissue Bcl-xL expression exceeded control values after Dox treatment. Taken together, these results demonstrated that SMN (i) reduced, delayed onset, or prevented toxic effects of Dox which are typically associated with

Hepatoprotective effects of Arctium lappa on carbon tetrachloride- and acetaminophen-induced liver damage.

Science.gov (United States)

Lin, S C; Chung, T C; Lin, C C; Ueng, T H; Lin, Y H; Lin, S Y; Wang, L Y

2000-01-01

The root of Arctium lappa Linne (A. lappa) (Compositae), a perennial herb, has been cultivated for a long time as a popular vegetable. In order to investigate the hepatoprotective effects of A. lappa, male ICR mice were injected with carbon tetrachloride (CCl4, 32 microl/kg, i.p.) or acetaminophen (600 mg/kg, i.p.). A. lappa suppressed the SGOT and SGPT elevations induced by CCl4 or acetaminophen in a dose-dependent manner and alleviated the severity of liver damage based on histopathological observations. In an attempt to elucidate the possible mechanism(s) of this hepatoprotective effect, glutathione (GSH), cytochrome P-450 (P-450) and malondialdehyde (MDA) contents were studied. A. lappa reversed the decrease in GSH and P-450 induced by CCl4 and acetaminophen. It was also found that A. lappa decreased the malondialdehyde (MDA) content in CCl4 or acetaminophen-intoxicated mice. From these results, it was suggested that A. lappa could protect the liver cells from CCl4 or acetaminophen-induced liver damages, perhaps by its antioxidative effect on hepatocytes, hence eliminating the deleterious effects of toxic metabolites from CCl4 or acetaminophen.

HBx induced AFP receptor expressed to activate PI3K/AKT signal to promote expression of Src in liver cells and hepatoma cells

International Nuclear Information System (INIS)

Zhu, Mingyue; Guo, Junli; Li, Wei; Xia, Hua; Lu, Yan; Dong, Xu; Chen, Yi; Xie, Xieju; Fu, Shigan; Li, Mengsen

2015-01-01

Hepatitis B virus (HBV)-X protein(HBx) is a transactivator of host several cellular genes including alpha-fetoprotein(AFP) and AFP receptor(AFPR) which contributes to HBV-associated tumor development. The expression of AFP/AFPR are correlated with hepatocellular carcinoma(HCC)-initial cells. But the role of AFP and AFPR in promoting occurrence of HBV-related HCC were still unclear. A total of 71 clinical patients’ liver specimens, normal human liver cells L-02 and HCC cell lines, PLC/PRF/5 were selected for analyzing the effects of HBx on expression of AFP, AFPR and Src. The expression of goal proteins were detected by Immunohistochemical stained and Western blotting; HBx-expressed vectors were constructed and transfected into L-02 cells, laser confocal microscopy was applied to observe expression and location of AFP, AFPR and Src in the normal liver cells and HCC cells, soft agar colony formation assay was used to observe colonies formed of the cells. We confirmed HBx gives preference to promote the expression of AFP and AFPR; HBx priors to up-regulate the expression of AFPR and AFP in L-02 cells and in normal liver specimens; AFPR signal been able to stimulate Src expression. The results also indicated that phosphatidylinositol 3-kinase(PI3K) inhibitors Ly294002 and GDC0941 effectively suppress AFPR mediated up-regulation expression of Src in AFPR positive HCC lines. HBx priors to drive the expression of AFP and AFPR to promote expression of Src in normal liver cells and hepatoma cells; AFP and AFPR maybe play pivotal role in HBV-related hepatocarcinogenesis; Targeting AFPR is an available therapeutic strategy of HCC. The online version of this article (doi:10.1186/s12885-015-1384-9) contains supplementary material, which is available to authorized users

Tim-3/galectin-9 regulate the homeostasis of hepatic NKT cells in a murine model of nonalcoholic fatty liver disease.

Science.gov (United States)

Tang, Zhao-Hui; Liang, Shuwen; Potter, James; Jiang, Xuan; Mao, Hai-Quan; Li, Zhiping

2013-02-15

T cell Ig and mucin domain (Tim)-3 is well known to interact with its natural ligand, Galectin-9 (Gal-9), to regulate T cell function. However, little is known about the function of Tim-3/Gal-9 signaling in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) mediated by hepatic NKT cells that also express Tim-3. In the current study, we define the role and the mechanism of Tim-3/Gal-9 signaling in hepatic NKT cell regulation in a mouse model of diet-induced NAFLD. Adult male wild-type or CD1d knockout C57BL/6 mice were fed a high-fat diet to induce steatosis. Some of the mice also received one or a combination of Gal-9, anti-IL-15R/IL-15 mAb, rIL-15, α-galactosylceramide, and multilamellar liposomes containing Cl(2)MDP. The expression of Tim-3 and various markers reflecting cell proliferation, activation, cytokine production, and apoptosis was analyzed. Liver histology, steatosis grade, and hepatic triglyceride content were also evaluated. In the liver, Tim-3(+) NKT cells are in an activated state, and Gal-9 directly induces Tim-3(+) NKT cell apoptosis and contributes to the depletion of NKT cells in diet-induced steatosis. However, Gal-9 also interacts with Tim-3-expressing Kupffer cells to induce secretion of IL-15, thus promoting NKT cell proliferation. Exogenous administration of Gal-9 significantly ameliorates diet-induced steatosis by modulating hepatic NKT cell function. In summary, the Tim-3/Gal-9-signaling pathway plays a critical role in the homeostasis of hepatic NKT cells through activation-induced apoptosis and secondary proliferation and, thus, contributes to the pathogenesis of NAFLD.

Tim-3/Galectin-9 Regulate the Homeostasis of Hepatic NKT Cells in a Murine Model of Nonalcoholic Fatty Liver Disease

Science.gov (United States)

Liang, Shuwen; Potter, James; Jiang, Xuan; Mao, Hai-Quan

2013-01-01

T cell Ig and mucin domain (Tim)-3 is well known to interact with its natural ligand, Galectin-9 (Gal-9), to regulate T cell function. However, little is known about the function of Tim-3/Gal-9 signaling in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) mediated by hepatic NKT cells that also express Tim-3. In the current study, we define the role and the mechanism of Tim-3/Gal-9 signaling in hepatic NKT cell regulation in a mouse model of diet-induced NAFLD. Adult male wild-type or CD1d knockout C57BL/6 mice were fed a high-fat diet to induce steatosis. Some of the mice also received one or a combination of Gal-9, anti–IL-15R/IL-15 mAb, rIL-15, α-galactosylceramide, and multilamellar liposomes containing Cl2MDP. The expression of Tim-3 and various markers reflecting cell proliferation, activation, cytokine production, and apoptosis was analyzed. Liver histology, steatosis grade, and hepatic triglyceride content were also evaluated. In the liver, Tim-3+ NKT cells are in an activated state, and Gal-9 directly induces Tim-3+ NKT cell apoptosis and contributes to the depletion of NKT cells in diet-induced steatosis. However, Gal-9 also interacts with Tim-3–expressing Kupffer cells to induce secretion of IL-15, thus promoting NKT cell proliferation. Exogenous administration of Gal-9 significantly ameliorates diet-induced steatosis by modulating hepatic NKT cell function. In summary, the Tim-3/Gal-9–signaling pathway plays a critical role in the homeostasis of hepatic NKT cells through activation-induced apoptosis and secondary proliferation and, thus, contributes to the pathogenesis of NAFLD. PMID:23296703

Generation and characterization of rat liver stem cell lines and their engraftment in a rat model of liver failure

Science.gov (United States)

Kuijk, Ewart W.; Rasmussen, Shauna; Blokzijl, Francis; Huch, Meritxell; Gehart, Helmuth; Toonen, Pim; Begthel, Harry; Clevers, Hans; Geurts, Aron M.; Cuppen, Edwin

2016-01-01

The rat is an important model for liver regeneration. However, there is no in vitro culture system that can capture the massive proliferation that can be observed after partial hepatectomy in rats. We here describe the generation of rat liver stem cell lines. Rat liver stem cells, which grow as cystic organoids, were characterized by high expression of the stem cell marker Lgr5, by the expression of liver progenitor and duct markers, and by low expression of hepatocyte markers, oval cell markers, and stellate cell markers. Prolonged cultures of rat liver organoids depended on high levels of WNT-signalling and the inhibition of BMP-signaling. Upon transplantation of clonal lines to a Fah−/− Il2rg−/− rat model of liver failure, the rat liver stem cells engrafted into the host liver where they differentiated into areas with FAH and Albumin positive hepatocytes. Rat liver stem cell lines hold potential as consistent reliable cell sources for pharmacological, toxicological or metabolic studies. In addition, rat liver stem cell lines may contribute to the development of regenerative medicine in liver disease. To our knowledge, the here described liver stem cell lines represent the first organoid culture system in the rat. PMID:26915950

Inhibition of type I NKT cells by retinoids or following sulfatide-mediated activation of type II NKT cells attenuates alcoholic liver disease

Science.gov (United States)

Maricic, Igor; Sheng, Huiming; Marrero, Idania; Seki, Ehikiro; Kisseleva, Tatiana; Chaturvedi, Som; Molle, Natasha; Mathews, K. Stephanie; Gao, Bin; Kumar, Vipin

2015-01-01

Innate immune mechanisms leading to liver injury following chronic alcohol ingestion are poorly understood. Natural killer T (NKT) cells, enriched in the liver and comprised of at least two distinct subsets, type I and type II, recognize different lipid antigens presented by CD1d molecules. We have investigated whether differential activation of NKT cell subsets orchestrates inflammatory events leading to alcoholic liver disease (ALD). We found that following chronic plus binge feeding of Lieber-DeCarli liquid diet in male C57BL/6 mice, type I but not type II NKT cells are activated leading to recruitment of inflammatory Gr-1highCD11b+ cells into liver. A central finding is that liver injury following alcohol feeding is dependent upon type I NKT cells. Thus liver injury is significantly inhibited in Jα18−/− mice deficient in type I NKT cells as well as following their inactivation by sulfatide-mediated activation of type II NKT cells. Furthermore we have identified a novel pathway involving all-trans retinoic acid (ATRA) and its receptor RARγ signaling that inhibits type I NKT cells and consequently ALD. A semi-quantitative PCR analysis of hepatic gene expression of some of the key proinflammatory molecules shared in human disease indicated that their upregulation in ALD is dependent upon type I NKT cells. Conclusion Type I but not type II NKT cells become activated following alcohol feeding. Type I NKT cells-induced inflammation and neutrophil recruitment results in liver tissue damage while type II NKT cells protect from injury in ALD. Inhibition of type I NKT cells by retinoids or by sulfatide prevents ALD. Since the CD1d pathway is highly conserved between mice and humans, NKT cell subsets might be targeted for potential therapeutic intervention in ALD. PMID:25477000