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

PubMed

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.

Thymidine kinase 2 deficiency-induced mtDNA depletion in mouse liver leads to defect β-oxidation.

PubMed

Zhou, Xiaoshan; Kannisto, Kristina; Curbo, Sophie; von Döbeln, Ulrika; Hultenby, Kjell; Isetun, Sindra; Gåfvels, Mats; Karlsson, Anna

2013-01-01

Thymidine kinase 2 (TK2) deficiency in humans causes mitochondrial DNA (mtDNA) depletion syndrome. To study the molecular mechanisms underlying the disease and search for treatment options, we previously generated and described a TK2 deficient mouse strain (TK2(-/-)) that progressively loses its mtDNA. The TK2(-/-) mouse model displays symptoms similar to humans harboring TK2 deficient infantile fatal encephalomyopathy. Here, we have studied the TK2(-/-) mouse model to clarify the pathological role of progressive mtDNA depletion in liver for the severe outcome of TK2 deficiency. We observed that a gradual depletion of mtDNA in the liver of the TK2(-/-) mice was accompanied by increasingly hypertrophic mitochondria and accumulation of fat vesicles in the liver cells. The levels of cholesterol and nonesterified fatty acids were elevated and there was accumulation of long chain acylcarnitines in plasma of the TK2(-/-) mice. In mice with hepatic mtDNA levels below 20%, the blood sugar and the ketone levels dropped. These mice also exhibited reduced mitochondrial β-oxidation due to decreased transport of long chain acylcarnitines into the mitochondria. The gradual loss of mtDNA in the liver of the TK2(-/-) mice causes impaired mitochondrial function that leads to defect β-oxidation and, as a result, insufficient production of ketone bodies and glucose. This study provides insight into the mechanism of encephalomyopathy caused by TK2 deficiency-induced mtDNA depletion that may be used to explore novel therapeutic strategies.

Thymidine Kinase 2 Deficiency-Induced mtDNA Depletion in Mouse Liver Leads to Defect β-Oxidation

PubMed Central

von Döbeln, Ulrika; Hultenby, Kjell; Isetun, Sindra; Gåfvels, Mats; Karlsson, Anna

2013-01-01

Thymidine kinase 2 (TK2) deficiency in humans causes mitochondrial DNA (mtDNA) depletion syndrome. To study the molecular mechanisms underlying the disease and search for treatment options, we previously generated and described a TK2 deficient mouse strain (TK2−/−) that progressively loses its mtDNA. The TK2−/− mouse model displays symptoms similar to humans harboring TK2 deficient infantile fatal encephalomyopathy. Here, we have studied the TK2−/− mouse model to clarify the pathological role of progressive mtDNA depletion in liver for the severe outcome of TK2 deficiency. We observed that a gradual depletion of mtDNA in the liver of the TK2−/− mice was accompanied by increasingly hypertrophic mitochondria and accumulation of fat vesicles in the liver cells. The levels of cholesterol and nonesterified fatty acids were elevated and there was accumulation of long chain acylcarnitines in plasma of the TK2−/− mice. In mice with hepatic mtDNA levels below 20%, the blood sugar and the ketone levels dropped. These mice also exhibited reduced mitochondrial β-oxidation due to decreased transport of long chain acylcarnitines into the mitochondria. The gradual loss of mtDNA in the liver of the TK2−/− mice causes impaired mitochondrial function that leads to defect β-oxidation and, as a result, insufficient production of ketone bodies and glucose. This study provides insight into the mechanism of encephalomyopathy caused by TK2 deficiency-induced mtDNA depletion that may be used to explore novel therapeutic strategies. PMID:23505564

Mouse decellularised liver scaffold improves human embryonic and induced pluripotent stem cells differentiation into hepatocyte-like cells

PubMed Central

Scottoni, Federico; Crowley, Claire; Fiadeiro, Rebeca; Maghsoudlou, Panagiotis; Pellegata, Alessandro Filippo; Mazzacuva, Francesca; Gjinovci, Asllan; Lyne, Anne-Marie; Zulini, Justine; Little, Daniel; Mosaku, Olukunbi; Kelly, Deirdre; De Coppi, Paolo; Gissen, Paul

2017-01-01

Liver transplantation is the definitive treatment of liver failure but donor organ shortage limits its availability. Stem cells are highly expandable and have the potential to differentiate into any specialist cell. Use of patient-derived induced Pluripotent Stem Cells (hiPSCs) has the additional advantage for organ regeneration therapies by removing the need for immunosuppression. We compared hepatocyte differentiation of human embryonic stem cells (hESCs) and hiPSCs in a mouse decellularised liver scaffold (3D) with standard in vitro protocol (2D). Mouse livers were decellularised preserving micro-architecture, blood vessel network and extracellular matrix. hESCs and hiPSCs were primed towards the definitive endoderm. Cells were then seeded either in 3D or 2D cultures and the hepatocyte differentiation was continued. Both hESCs and hiPSCs differentiated more efficiently in 3D than in 2D, with higher and earlier expression of mature hepatocyte marker albumin, lipid and glycogen synthesis associated with a decrease in expression of fetal hepatocyte marker alpha-fetoprotein. Thus we conclude that stem cell hepatocyte differentiation in 3D culture promotes faster cell maturation. This finding suggests that optimised 3D protocols could allow generation of mature liver cells not achieved so far in standard 2D conditions and lead to improvement in cell models of liver disease and regenerative medicine applications. PMID:29261712

Liver carcinogenesis by FOS-dependent inflammation and cholesterol dysregulation

PubMed Central

Bakiri, Latifa; Hamacher, Rainer; Graña, Osvaldo; Guío-Carrión, Ana; Martinez, Lola; Dienes, Hans P.; Thomsen, Martin K.; Hasenfuss, Sebastian C.

2017-01-01

Human hepatocellular carcinomas (HCCs), which arise on a background of chronic liver damage and inflammation, express c-Fos, a component of the AP-1 transcription factor. Using mouse models, we show that hepatocyte-specific deletion of c-Fos protects against diethylnitrosamine (DEN)-induced HCCs, whereas liver-specific c-Fos expression leads to reversible premalignant hepatocyte transformation and enhanced DEN-carcinogenesis. c-Fos–expressing livers display necrotic foci, immune cell infiltration, and altered hepatocyte morphology. Furthermore, increased proliferation, dedifferentiation, activation of the DNA damage response, and gene signatures of aggressive HCCs are observed. Mechanistically, c-Fos decreases expression and activity of the nuclear receptor LXRα, leading to increased hepatic cholesterol and accumulation of toxic oxysterols and bile acids. The phenotypic consequences of c-Fos expression are partially ameliorated by the anti-inflammatory drug sulindac and largely prevented by statin treatment. An inverse correlation between c-FOS and the LXRα pathway was also observed in human HCC cell lines and datasets. These findings provide a novel link between chronic inflammation and metabolic pathways important in liver cancer. PMID:28356389

Identification of Noninvasive Biomarkers for Alcohol-Induced Liver Disease Using Urinary Metabolomics and the Ppara-null Mouse

PubMed Central

Manna, Soumen K.; Patterson, Andrew D.; Yang, Qian; Krausz, Kristopher W.; Li, Henghong; Idle, Jeffrey R.; Fornace, Albert J.; Gonzalez, Frank J.

2010-01-01

Alcohol-induced liver disease (ALD) is a leading cause of non-accident-related deaths in the United States. Although liver damage caused by ALD is reversible when discovered at the earlier stages, current risk assessment tools are relatively non-specific. Identification of an early specific signature of ALD would aid in therapeutic intervention and recovery. In this study the metabolic changes associated with alcohol-induced liver disease were examined using alcohol-fed male Ppara-null mouse as a model of ALD. Principal components analysis of the mass spectrometry-based urinary metabolic profile showed that alcohol-treated wild-type and Ppara-null mice could be distinguished from control animals without information on history of alcohol consumption. The urinary excretion of ethyl-sulfate, ethyl-β-D-glucuronide, 4-hydroxyphenylacetic acid, and 4-hydroxyphenylacetic acid sulfate was elevated and that of the 2-hydroxyphenylacetic acid, adipic acid, and pimelic acid was depleted during alcohol treatment in both wild-type and the Ppara-null mice albeit to different extents. However, indole-3-lactic acid was exclusively elevated by alcohol exposure in Ppara-null mice. The elevation of indole-3-lactic acid is mechanistically related to the molecular events associated with development of ALD in alcohol-treated Ppara-null mice. This study demonstrated the ability of metabolomics approach to identify early, noninvasive biomarkers of ALD pathogenesis in Ppara-null mouse model. PMID:20540569

Altered microRNA expression induced by tumorigenic conazoles in mouse liver.

EPA Science Inventory

Triadimefon, propiconazole, and myclobutanil are conazoles, an important class of agricultural and therapeutic fungicides. Triadimefon and propiconazole are mouse liver tumorigens, while myclobutanil is not. As part of a coordinated study to understand the molecular determinants ...

Glutamine inhibits CCl4 induced liver fibrosis in mice and TGF-β1 mediated epithelial-mesenchymal transition in mouse hepatocytes.

PubMed

Shrestha, Nirajan; Chand, Lokendra; Han, Myung Kwan; Lee, Seung Ok; Kim, Chan Young; Jeong, Yeon Jun

2016-07-01

Glutamine, traditionally a non-essential amino acid, now has been considered as essential in serious illness and injury. It is a major precursor for glutathione synthesis. However, the anti-fibrotic effect of glutamine and its molecular mechanism in experimental liver fibrosis have not been explored. In the present study we aimed to examine the potential role of glutamine in carbon tetrachloride (CCl4) induced liver fibrosis and TGF-β1 mediated epithelial mesenchymal transition (EMT) and apoptosis in mouse hepatocytes. Liver fibrosis was induced by intraperitoneal injection of CCl4 three times a week for 10 weeks. Glutamine treatment effectively attenuated liver injury and oxidative stress. Collagen content was significantly decreased in liver sections of glutamine treated mice compared to CCl4 model mice. Furthermore, glutamine decreased expression level of α-SMA and TGF-β in liver tissue. Our in vitro study showed that TGF-β1 treatment in hepatocytes resulted in loss of E-cadherin and increased expression of mesenchymal markers and EMT related transcription factor. In addition, TGF-β1 increased the expression of apoptotic markers. However, glutamine interestingly suppressed TGF-β1 mediated EMT and apoptosis. In conclusion, our results suggest that glutamine ameliorates CCl4 induced liver fibrosis and suppresses TGF-β1 induced EMT progression and apoptosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

PPARÁ-DEPENDENT GENE EXPRESSION CHANGES IN THE MOUSE LIVER AFTER EXPOSURE TO PEROXISOME PROLIFERATORS

EPA Science Inventory

Peroxisome proliferators (PP) are a large class of structurally diverse chemicals that mediate their effects in the liver mainly through the PP-activated receptor ¿ (PPARα). Development of PP induced hepatocarcinogenesis in mouse liver is known to be dependent on PPAR&#...

Blockade of CCN4 attenuates CCl4-induced liver fibrosis.

PubMed

Li, Xiaofei; Chen, Yongxin; Ye, Weiwei; Tao, Xingfei; Zhu, Jinhong; Wu, Shuang; Lou, Lianqing

2015-06-19

CCN4, also termed WNT-inducible signaling pathway protein-1 (WISP-1), has important roles in inflammation and tissue injury. This study aimed to investigate the effect of CCN4 inhibition using monoclonal anti-CCN4 antibody (CCN4mAb) on the liver injury and fibrosis in a mouse model of liver fibrosis. The mouse liver fibrosis model was induced by carbon tetrachloride (CCl4). Mice received vehicle (saline/olive oil) by subcutaneous injection, CCl4 by subcutaneous injection or CCl4 (subcutaneous) plus CCN4mAb by subcutaneous injection. The pro-inflammatory and pro-fibrotic factors were determined by Western blot. The biochemistry and histopathology, collagen deposition and nuclear factor (NF)-κB activity were also assessed. Chronic CCl4 treatment caused liver injury and collagen accumulation. The expression levels of CCN4, pro-inflammatory and pro-fibrotic mediators as well as the activity of NF-κB were markedly increased. Treatment with CCN4mAb significantly inhibited CCl4-induced CCN4 expression, leading to attenuated CCl4-induced liver injury and the inflammatory response. CCN4 blockade also significantly reduced the formation of collagen in the liver and the expression of α-smooth muscle actin and transforming growth factor β1. CCN4 inhibition by CCN4mAb in vivo significantly attenuated the CCl4-induced liver injury and the progression of liver fibrosis. CCN4 may represent a novel therapeutic target for liver injury and fibrosis.

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

PubMed Central

Yamazaki, Yuichi; Moore, Rick; Negishi, Masahiko

2014-01-01

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. PMID:21826054

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

PubMed

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.

Assessment of amiodarone-induced phospholipidosis in chimeric mice with a humanized liver.

PubMed

Sanoh, Seigo; Yamachika, Yuto; Tamura, Yuka; Kotake, Yaichiro; Yoshizane, Yasumi; Ishida, Yuji; Tateno, Chise; Ohta, Shigeru

2017-01-01

It is important to consider susceptibility to drug-induced toxicity between animals and humans. Chimeric mice with a humanized liver are expected to predict hepatotoxicity in humans. Drug-induced phospholipidosis (DIPL), in which phospholipids accumulate, is a known entity. In this study, we examined whether chimeric mice can reveal species differences in DIPL. Changes in various phosphatidylcholine (PhC) molecules were investigated in the liver of chimeric mice after administering amiodarone, which induces phospholipidosis. Liquid chromatography-tandem mass spectrometry revealed that levels of PhCs tended to increase in the liver after administration of amiodarone. The liver of chimeric mice consists of human hepatocytes and residual mouse hepatocytes. We used imaging mass spectrometry (IMS) to evaluate the increase of PhCs in human and mouse hepatocytes after administration of amiodarone. IMS visualizes localization of endogenous and exogenous molecules in tissues. The IMS analysis suggested that the localized levels of several PhCs tended to be higher in the human hepatocytes than those in mouse hepatocytes, and PhC levels changed in response to amiodarone. Chimeric mice with a humanized liver will be useful to evaluate species differences in DIPL between mice and humans.

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

PubMed Central

Yan, Yaping; Wang, Junfeng; Duan, Yanchao; Li, Shanshan; Yan, Li; Wang, Hong; Chen, Bingbing; Sang, Xiongbo; Ji, Weizhi

2018-01-01

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 paracrine

MOUSE LIVER TUMOR DATA: ASSESSMENT OF CARCINOGENIC ACTIVITY

EPA Science Inventory

A significant number of chemicals have been shown to be carcinogenic in mouse liver while lacking carcinogenic activity in other organs or tissues of mice or rats. The review focus on the reasons for the unique susceptibility of the mouse liver to these carcinogens, and the exten...

Identification of Plants That Inhibit Lipid Droplet Formation in Liver Cells: Rubus suavissimus Leaf Extract Protects Mice from High-Fat Diet-Induced Fatty Liver by Directly Affecting Liver Cells

PubMed Central

Takahashi, Tomohiro; Sugawara, Wataru; Takiguchi, Yuya; Takizawa, Kento; Nakabayashi, Ami; Nakamura, Mitsuo; Nagano-Ito, Michiyo; Ichikawa, Shinichi

2016-01-01

Fatty liver disease is a condition in which abnormally large numbers of lipid droplets accumulate in liver cells. Fatty liver disease induces inflammation under conditions of oxidative stress and may result in cancer. To identify plants that protect against fatty liver disease, we examined the inhibitory effects of plant extracts on lipid droplet formation in mouse hepatoma cells. A screen of 98 water extracts of plants revealed 4 extracts with inhibitory effects. One of these extracts, Rubus suavissimus S. Lee (Tien-cha or Chinese sweet tea) leaf extract, which showed strong inhibitory effects, was tested in a mouse fatty liver model. In these mouse experiments, intake of the plant extract significantly protected mice against fatty liver disease without affecting body weight gain. Our results suggest that RSE directly affects liver cells and protects them from fatty liver disease. PMID:27429636

Gpr110 deficiency decelerates carcinogen-induced hepatocarcinogenesis via activation of the IL-6/STAT3 pathway

PubMed Central

Ma, Benting; Zhu, Junjie; Tan, Juan; Mao, Yulei; Tang, Lingyun; Shen, Chunling; Zhang, Hongxing; Kuang, Ying; Fei, Jian; Yang, Xiao; Wang, Zhugang

2017-01-01

Hepatocarcinogenesis is a complex process that includes pronounced necroinflammation, unregulated hepatocyte damage, subsequent extensive fibrosis, and carcinogenesis. GPR110 was an adhesion G protein-coupled receptor. Analysis of the expression pattern of Gpr110 in mice displayed that Gpr110 was expressed highly in liver, implicating the tissue compartments where Gpr110 could execute its functions, the role of Gpr110 in the physiological and pathological state of liver remains unclear. Based on a Gpr110 knockout mouse model, we evaluated the role of Gpr110 in hepatocarcinogenesis by using a carbon tetrachloride (CCl4)-induced liver injury and fibrosis model, as well as diethylnitrosamine (DEN) plus CCl4-induced liver cancer model. In this study, we found subdued chronic liver injury, reduced compensatory proliferation, lower liver fibrosis, but enhanced inflammation occurred in Gpr110-/- mice during CCl4 challenge. In addition, Gpr110-/- mice were resistant to liver tumorigenesis induced by DEN plus CCl4 injection. Molecular mechanisms underlying these differences correlated with augmented activation of the IL-6/STAT3 pathway, which exerted hepatoprotective effects during liver damage, fibrosis, and oncogenesis in Gpr110-/- mice. Furthermore, pharmacological inhibition of the activation of the IL-6/STAT3 pathway enhanced hepatic fibrosis and promoted DEN plus CCl4-induced carcinogenesis in Gpr110-/- mice. In summary, absence of Gpr110 decelerates liver fibrosis/cirrhosis progressing into tumorigenesis, due to strengthening activation of the IL-6/STAT3 pathway, leading to a weaker liver injury and fibrosis microenvironment. It is indicated that targeting Gpr110 and activating the IL-6/STAT3 pathway may be considered to be preventive methods for some cirrhosis transition. PMID:28401002

Liver Transplantation in the Mouse: Insights Into Liver Immunobiology, Tissue Injury and Allograft Tolerance

PubMed Central

Yokota, Shinichiro; Yoshida, Osamu; Ono, Yoshihiro; Geller, David A.; Thomson, Angus W.

2016-01-01

The surgically-demanding mouse orthotopic liver transplant model was first described in 1991. It has proved a powerful research tool for investigation of liver biology, tissue injury, the regulation of alloimmunity and tolerance induction and the pathogenesis of specific liver diseases. Liver transplantation in mice has unique advantages over transplantation of the liver in larger species, such as the rat or pig, since the mouse genome is well-characterized and there is much greater availability of both genetically-modified animals and research reagents. Liver transplant experiments using various transgenic or gene knockout mice has provided valuable mechanistic insights into the immuno- and pathobiology of the liver and the regulation of graft rejection and tolerance over the past 25 years. The molecular pathways identified in regulation of tissue injury and promotion of liver transplant tolerance provide new potential targets for therapeutic intervention to control adverse inflammatory responses/ immune-mediated events in the hepatic environment and systemically. Conclusion: Orthotopic liver transplantation in the mouse is a valuable model for gaining improved insights into liver biology, immunopathology and allograft tolerance that may result in therapeutic innovation in liver and other diseases. PMID:26709949

UDP-Glucuronosyltransferase Expression in Mouse Liver Is Increased in Obesity- and Fasting-Induced Steatosis

PubMed Central

Xu, Jialin; Kulkarni, Supriya R.; Li, Liya

2012-01-01

UDP-glucuronosyltransferases (Ugt) catalyze phase II conjugation reactions with glucuronic acid, which enhances chemical polarity and the elimination from the body. Few studies have addressed whether Ugt expression and activity are affected by liver disease, such as steatosis. The purpose of this study was to determine whether steatosis induced by obesity or fasting could affect liver Ugt mRNA expression and activity. Male C57BL/6J and Lepob/ob (ob/ob) mice were fed ad libitum or food was withheld for 24 h. In steatotic livers of ob/ob mice, Ugt1a1, -1a6, -1a9, -2a3, -3a1, and -3a2 mRNA expression increased. Fasting, which also induced steatosis, increased hepatic Ugt1a1, -1a6, -1a7, -1a9, -2b1, -2b5, -2a3, -3a1, and -3a2 mRNA expression in mouse liver. Likewise, acetaminophen glucuronidation increased by 47% in hepatic microsomes from ob/ob mice compared with that in C57BL/6J mice, but not after fasting. In both steatosis models, Ugt induction was accompanied by increased aryl hydrocarbon receptor, constitutive androstane receptor (CAR), peroxisome proliferator-activated receptor (PPAR)-α, pregnane X receptor, nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and peroxisome proliferator-activated receptor-γ coactivator-1α mRNA expression. In addition, fasting increased CAR, PPAR, and Nrf2 binding activity. The work points to hepatic triglyceride concentrations corresponding with nuclear receptor and Ugt expression. The findings indicate that steatosis significantly alters hepatic Ugt expression and activity, which could have a significant impact on determining circulating hormone levels, drug efficacy, and environmental chemical clearance. PMID:22031624

UDP-glucuronosyltransferase expression in mouse liver is increased in obesity- and fasting-induced steatosis.

PubMed

Xu, Jialin; Kulkarni, Supriya R; Li, Liya; Slitt, Angela L

2012-02-01

UDP-glucuronosyltransferases (Ugt) catalyze phase II conjugation reactions with glucuronic acid, which enhances chemical polarity and the elimination from the body. Few studies have addressed whether Ugt expression and activity are affected by liver disease, such as steatosis. The purpose of this study was to determine whether steatosis induced by obesity or fasting could affect liver Ugt mRNA expression and activity. Male C57BL/6J and Lep(ob/ob) (ob/ob) mice were fed ad libitum or food was withheld for 24 h. In steatotic livers of ob/ob mice, Ugt1a1, -1a6, -1a9, -2a3, -3a1, and -3a2 mRNA expression increased. Fasting, which also induced steatosis, increased hepatic Ugt1a1, -1a6, -1a7, -1a9, -2b1, -2b5, -2a3, -3a1, and -3a2 mRNA expression in mouse liver. Likewise, acetaminophen glucuronidation increased by 47% in hepatic microsomes from ob/ob mice compared with that in C57BL/6J mice, but not after fasting. In both steatosis models, Ugt induction was accompanied by increased aryl hydrocarbon receptor, constitutive androstane receptor (CAR), peroxisome proliferator-activated receptor (PPAR)-α, pregnane X receptor, nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and peroxisome proliferator-activated receptor-γ coactivator-1α mRNA expression. In addition, fasting increased CAR, PPAR, and Nrf2 binding activity. The work points to hepatic triglyceride concentrations corresponding with nuclear receptor and Ugt expression. The findings indicate that steatosis significantly alters hepatic Ugt expression and activity, which could have a significant impact on determining circulating hormone levels, drug efficacy, and environmental chemical clearance.

An Animal Model of Abacavir-Induced HLA-Mediated Liver Injury.

PubMed

Song, Binbin; Aoki, Shigeki; Liu, Cong; Susukida, Takeshi; Ito, Kousei

2018-04-01

Genome-wide association studies indicate that several idiosyncratic adverse drug reactions are highly associated with specific human leukocyte antigen (HLA) alleles. For instance, abacavir, a human immunodeficiency virus reverse transcriptase inhibitor, induces multiorgan toxicity exclusively in patients carrying the HLA-B*57:01 allele. However, the underlying mechanism is unclear due to a lack of appropriate animal models. Previously, we developed HLA-B*57:01 transgenic mice and found that topical application of abacavir to the ears induced proliferation of CD8+ lymphocytes in local lymph nodes. Here, we attempted to reproduce abacavir-induced liver injury in these mice. However, oral administration of abacavir alone to HLA-B*57:01 transgenic mice did not increase levels of the liver injury marker alanine aminotransferase. Considering the importance of innate immune activation in mouse liver, we treated mice with CpG oligodeoxynucleotide, a toll-like receptor 9 agonist, plus abacavir. This resulted in a marked increase in alanine aminotransferase, pathological changes in liver, increased numbers of activated CD8+ T cells, and tissue infiltration by immune cells exclusively in HLA-B*57:01 transgenic mice. These results indicate that CpG oligodeoxynucleotide-induced inflammatory reactions and/or innate immune activation are necessary for abacavir-induced HLA-mediated liver injury characterized by infiltration of CD8+ T cells. Thus, we developed the first mouse model of HLA-mediated abacavir-induced idiosyncratic liver injury. Further investigation will show that the proposed HLA-mediated liver injury model can be applied to other combinations of drugs and HLA types, thereby improving drug development and contributing to the development of personalized medicine.

GW501516 acts as an efficient PPARα activator in the mouse liver.

PubMed

Terada, M; Araki, M; Ashibe, B; Motojima, K

2011-08-01

The peroxisome proliferator-activated receptor (PPAR) subtype specificity of GW501516, a well-known PPARδ-specific agonist, was studied by examining its effects on the expression of endogenous genes in primary hepatocytes and the liver of wild-type and PPARα-null mice. GW501516, like the PPARα-specific agonist Wy14,643, induced the expression of several PPAR target genes in a dose-dependent manner but this action was mostly absent in the cells and liver of PPARα-null mice. Results indicated that GW501516 acts as an efficient PPARα activator in the mouse liver.

Liver BCATm transgenic mouse model reveals the important role of the liver in maintaining BCAA homeostasis.

PubMed

Ananieva, Elitsa A; Van Horn, Cynthia G; Jones, Meghan R; Hutson, Susan M

2017-02-01

Unlike other amino acids, the branched-chain amino acids (BCAAs) largely bypass first-pass liver degradation due to a lack of hepatocyte expression of the mitochondrial branched-chain aminotransferase (BCATm). This sets up interorgan shuttling of BCAAs and liver-skeletal muscle cooperation in BCAA catabolism. To explore whether complete liver catabolism of BCAAs may impact BCAA shuttling in peripheral tissues, the BCATm gene was stably introduced into mouse liver. Two transgenic mouse lines with low and high hepatocyte expression of the BCATm transgene (LivTg-LE and LivTg-HE) were created and used to measure liver and plasma amino acid concentrations and determine whether the first two BCAA enzymatic steps in liver, skeletal muscle, heart and kidney were impacted. Expression of the hepatic BCATm transgene lowered the concentrations of hepatic BCAAs while enhancing the concentrations of some nonessential amino acids. Extrahepatic BCAA metabolic enzymes and plasma amino acids were largely unaffected, and no growth rate or body composition differences were observed in the transgenic animals as compared to wild-type mice. Feeding the transgenic animals a high-fat diet did not reverse the effect of the BCATm transgene on the hepatic BCAA catabolism, nor did the high-fat diet cause elevation in plasma BCAAs. However, the high-fat-diet-fed BCATm transgenic animals experienced attenuation in the mammalian target of rapamycin (mTOR) pathway in the liver and had impaired blood glucose tolerance. These results suggest that complete liver BCAA metabolism influences the regulation of glucose utilization during diet-induced obesity. Copyright © 2016 Elsevier Inc. All rights reserved.

Liver BCATm transgenic mouse model reveals the important role of the liver in maintaining BCAA homeostasis

PubMed Central

Ananieva, Elitsa A.; Van Horn, Cynthia G.; Jones, Meghan R.; Hutson, Susan M.

2016-01-01

Unlike other amino acids, the branched chain amino acids (BCAAs) largely bypass first pass liver degradation due to a lack of hepatocyte expression of the mitochondrial branched chain aminotransferase (BCATm). This sets up interorgan shuttling of BCAAs and liver-skeletal muscle cooperation in BCAA catabolism. To explore whether complete liver catabolism of BCAAs may impact BCAA shuttling in peripheral tissues, the BCATm gene was stably introduced into mouse liver. Two transgenic mouse lines with low and high hepatocyte expression of the BCATm transgene (LivTg-LE and LivTg-HE) were created and used to measure liver and plasma amino acid concentrations and determine whether the first two BCAA enzymatic steps in liver, skeletal muscle, heart, and kidney were impacted. Expression of the hepatic BCATm transgene lowered the concentrations of hepatic BCAAs while enhancing the concentrations of some nonessential amino acids. Extrahepatic BCAA metabolic enzymes and plasma amino acids were largely unaffected and no growth rate or body composition differences were observed in the transgenic animals as compared to wild type (WT) mice. Feeding the transgenic animals a high fat diet did not reverse the effect of the BCATm transgene on the hepatic BCAA catabolism nor did the high fat diet cause elevation in plasma BCAAs. However, the high fat diet fed BCATm transgenic animals experienced attenuation in the mammalian target of rapamycin (mTOR) pathway in the liver and had impaired blood glucose tolerance. These results suggest that complete liver BCAA metabolism influences the regulation of glucose utilization during diet-induced obesity. PMID:27886623

Iron chelation as a possible mechanism for aspirin-induced malondialdehyde production by mouse liver microsomes and mitochondria.

PubMed Central

Schwarz, K B; Arey, B J; Tolman, K; Mahanty, S

1988-01-01

To investigate the possibility that lipid peroxidation is the mechanism responsible for aspirin-induced liver damage, pure neutralized acetylsalicylic acid (ASA), 0.6-90.9 mM, was added to calcium-aggregated mouse liver microsomes followed by incubation in NADPH buffer at 37 degrees C for 60 min and subsequent measurement of malondialdehyde (MDA). MDA production at ASA concentrations from 1.2 to 4.6 mM was greater than control (P less than 0.004). Peak MDA values were observed with 4.6 mM ASA, 39.58 +/- 6.73 nmol MDA/mg protein vs. 16.16 +/- 2.85 (P less than 0.004). Higher concentrations of ASA were inhibitory compared with the value at 4.6 mM (P less than 0.001). Aspirin had similar effects on MDA production by mouse liver mitochondria. MDA production with either ASA or buffer was completely suppressed by the potent iron-chelating agents desferrioxamine and alpha,alpha' dipyridyl when these were added to the microsomal preparations. Since MDA production in this system is known to be affected by iron-chelating agents (enhanced at low concentration, inhibited at higher concentration), the iron-chelating properties of ASA were investigated. Conductivity titration curves of Fe(OH)3 added to water or ASA suggested that the ASA was complexing with iron. The presence of an iron-ASA complex was established by high pressure liquid chromatographic analysis of the solution from this study. We conclude that aspirin enhances MDA production by hepatic microsomes and mitochondria via an aspirin-iron chelate and that this represents at least one mechanism by which aspirin may produce liver damage. PMID:3335633

Alcoholic Liver Disease: A Mouse Model Reveals Protection by Lactobacillus fermentum

PubMed Central

Barone, Rosario; Rappa, Francesca; Macaluso, Filippo; Caruso Bavisotto, Celeste; Sangiorgi, Claudia; Di Paola, Gaia; Tomasello, Giovanni; Di Felice, Valentina; Marcianò, Vito; Farina, Felicia; Zummo, Giovanni; Conway de Macario, Everly; J.L. Macario, Alberto; Cocchi, Massimo; Cappello, MD, Francesco; Marino Gammazza, Antonella

2016-01-01

Objectives: Alcoholism is one of the most devastating diseases with high incidence, but knowledge of its pathology and treatment is still plagued with gaps mostly because of the inherent limitations of research with patients. We developed an animal model for studying liver histopathology, Hsp (heat-shock protein)-chaperones involvement, and response to treatment. Methods: The system was standardized using mice to which ethanol was orally administered alone or in combination with Lactobacillus fermentum following a precise schedule over time and applying, at predetermined intervals, a battery of techniques (histology, immunohistochemistry, western blotting, real-time PCR, immunoprecipitation, 3-nitrotyrosine labeling) to assess liver pathology (e.g., steatosis, fibrosis), and Hsp60 and iNOS (inducible form of nitric oxide synthase) gene expression and protein levels, and post-translational modifications. Results: Typical ethanol-induced liver pathology occurred and the effect of the probiotic could be reliably monitored. Steatosis score, iNOS levels, and nitrated proteins (e.g., Hsp60) decreased after probiotic intake. Conclusions: We describe a mouse model useful for studying liver disease induced by chronic ethanol intake and for testing pertinent therapeutic agents, e.g., probiotics. We tested L. fermentum, which reduced considerably ethanol-induced tissue damage and deleterious post-translational modifications of the chaperone Hsp60. The model is available to test other agents and probiotics with therapeutic potential in alcoholic liver disease. PMID:26795070

Augmenter of liver regeneration protects against carbon tetrachloride-induced liver injury by promoting autophagy in mice

PubMed Central

Shi, Hongbo; Han, Weijia; Shi, Honglin; Ren, Feng; Chen, Dexi; Chen, Yu; Duan, Zhongping

2017-01-01

Background Augmenter of liver regeneration (ALR) exerts strong hepatoprotective properties in various animal models of liver injury, but its protective mechanisms have not yet been explored. Autophagy is a recently recognized rudimentary cellular response to inflammation and injury. The aim of this study was to test the hypothesis that ALR may protect against acute liver injury through the autophagic pathway. Methods The level and role of ALR in liver injury were studied in a mouse model of acute liver injury induced by carbon tetrachloride (CCl4). The effect of ALR on autophagy was analyzed in vitro and in vivo. After autophagy was inhibited by 3-methyladenine (3-MA), apoptosis and proliferation were detected in the mouse model with acute liver injury. The ALR and autophagic levels were measured in patients with liver cirrhosis (LC) and acute liver failure (ALF), respectively. Results During the progression of acute liver injury, the ALR levels increased slightly in early stage and significantly decreased in late stage in mice Treatment with an ALR plasmid via tail vein injection protected mice against acute liver injury. The protective effect of ALR relied on the induction of autophagy, which was supported by the following evidence: (1) ALR overexpression directly induced autophagy flux in vitro and in vivo; and (2) ALR treatment suppressed apoptosis and promoted proliferation in mice exposed to CCl4, but the inhibition of autophagy reversed these effects. More importantly, the ALR levels decreased in patients with LC and ALF compared with normal controls. Conclusion We demonstrated that ALR ameliorated liver injury via an autophagic mechanism, which indicates a potential therapeutic application for liver injury. PMID:28061452

Metabolite identification in fecal microbiota transplantation mouse livers and combined proteomics with chronic unpredictive mild stress mouse livers.

PubMed

Li, Bo; Guo, Kenan; Zeng, Li; Zeng, Benhua; Huo, Ran; Luo, Yuanyuan; Wang, Haiyang; Dong, Meixue; Zheng, Peng; Zhou, Chanjuan; Chen, Jianjun; Liu, Yiyun; Liu, Zhao; Fang, Liang; Wei, Hong; Xie, Peng

2018-01-31

Major depressive disorder (MDD) is a common mood disorder. Gut microbiota may be involved in the pathogenesis of depression via the microbe-gut-brain axis. Liver is vulnerable to exposure of bacterial products translocated from the gut via the portal vein and may be involved in the axis. In this study, germ-free mice underwent fecal microbiota transplantation from MDD patients and healthy controls. Behavioral tests verified the depression model. Metabolomics using gas chromatography-mass spectrometry, nuclear magnetic resonance, and liquid chromatography-mass spectrometry determined the influence of microbes on liver metabolism. With multivariate statistical analysis, 191 metabolites were distinguishable in MDD mice from control (CON) mice. Compared with CON mice, MDD mice showed lower levels for 106 metabolites and higher levels for 85 metabolites. These metabolites are associated with lipid and energy metabolism and oxidative stress. Combined analyses of significantly changed proteins in livers from another depression model induced by chronic unpredictive mild stress returned a high score for the Lipid Metabolism, Free Radical Scavenging, and Molecule Transports network, and canonical pathways were involved in energy metabolism and tryptophan degradation. The two mouse models of depression suggest that changes in liver metabolism might be involved in the pathogenesis of MDD. Conjoint analyses of fecal, serum, liver, and hippocampal metabolites from fecal microbiota transplantation mice suggested that aminoacyl-tRNA biosynthesis significantly changed and fecal metabolites showed a close relationship with the liver. These findings may help determine the biological mechanisms of depression and provide evidence about "depression microbes" impacting on liver metabolism.

Bone morphogenetic protein-binding endothelial regulator of liver sinusoidal endothelial cells induces iron overload in a fatty liver mouse model.

PubMed

Hasebe, Takumu; Tanaka, Hiroki; Sawada, Koji; Nakajima, Shunsuke; Ohtake, Takaaki; Fujiya, Mikihiro; Kohgo, Yutaka

2017-03-01

Non-alcoholic fatty liver disease (NAFLD) is frequently accompanied by iron overload. However, because of the complex hepcidin-regulating molecules, the molecular mechanism underlying iron overload remains unknown. To identify the key molecule involved in NAFLD-associated iron dysregulation, we performed whole-RNA sequencing on the livers of obese mice. Male C57BL/6 mice were fed a regular or high-fat diet for 16 or 48 weeks. Internal iron was evaluated by plasma iron, ferritin or hepatic iron content. Whole-RNA sequencing was performed by transcriptome analysis using semiconductor high-throughput sequencer. Mouse liver tissues or isolated hepatocytes and sinusoidal endothelial cells were used to assess the expression of iron-regulating molecules. Mice fed a high-fat diet for 16 weeks showed excess iron accumulation. Longer exposure to a high-fat diet increased hepatic fibrosis and intrahepatic iron accumulation. A pathway analysis of the sequencing data showed that several inflammatory pathways, including bone morphogenetic protein (BMP)-SMAD signaling, were significantly affected. Sequencing analysis showed 2314 altered genes, including decreased mRNA expression of the hepcidin-coding gene Hamp. Hepcidin protein expression and SMAD phosphorylation, which induces Hamp, were found to be reduced. The expression of BMP-binding endothelial regulator (BMPER), which inhibits BMP-SMAD signaling by binding BMP extracellularly, was up-regulated in fatty livers. In addition, immunohistochemical and cell isolation analyses showed that BMPER was primarily expressed in the liver sinusoidal endothelial cells (LSECs) rather than hepatocytes. BMPER secretion by LSECs inhibits BMP-SMAD signaling in hepatocytes and further reduces hepcidin protein expression. These intrahepatic molecular interactions suggest a novel molecular basis of iron overload in NAFLD.

Targeted induction of interferon-λ in humanized chimeric mouse liver abrogates hepatotropic virus infection.

PubMed

Nakagawa, Shin-ichiro; Hirata, Yuichi; Kameyama, Takeshi; Tokunaga, Yuko; Nishito, Yasumasa; Hirabayashi, Kazuko; Yano, Junichi; Ochiya, Takahiro; Tateno, Chise; Tanaka, Yasuhito; Mizokami, Masashi; Tsukiyama-Kohara, Kyoko; Inoue, Kazuaki; Yoshiba, Makoto; Takaoka, Akinori; Kohara, Michinori

2013-01-01

The interferon (IFN) system plays a critical role in innate antiviral response. We presume that targeted induction of IFN in human liver shows robust antiviral effects on hepatitis C virus (HCV) and hepatitis B virus (HBV). This study used chimeric mice harboring humanized livers and infected with HCV or HBV. This mouse model permitted simultaneous analysis of immune responses by human and mouse hepatocytes in the same liver and exploration of the mechanism of antiviral effect against these viruses. Targeted expression of IFN was induced by treating the animals with a complex comprising a hepatotropic cationic liposome and a synthetic double-stranded RNA analog, pIC (LIC-pIC). Viral replication, IFN gene expression, IFN protein production, and IFN antiviral activity were analyzed (for type I, II and III IFNs) in the livers and sera of these humanized chimeric mice. Following treatment with LIC-pIC, the humanized livers of chimeric mice exhibited increased expression (at the mRNA and protein level) of human IFN-λs, resulting in strong antiviral effect on HBV and HCV. Similar increases were not seen for human IFN-α or IFN-β in these animals. Strong induction of IFN-λs by LIC-pIC occurred only in human hepatocytes, and not in mouse hepatocytes nor in human cell lines derived from other (non-hepatic) tissues. LIC-pIC-induced IFN-λ production was mediated by the immune sensor adaptor molecules mitochondrial antiviral signaling protein (MAVS) and Toll/IL-1R domain-containing adaptor molecule-1 (TICAM-1), suggesting dual recognition of LIC-pIC by both sensor adaptor pathways. These findings demonstrate that the expression and function of various IFNs differ depending on the animal species and tissues under investigation. Chimeric mice harboring humanized livers demonstrate that IFN-λs play an important role in the defense against human hepatic virus infection.

CD24-Positive Cells from Normal Adult Mouse Liver Are Hepatocyte Progenitor Cells

PubMed Central

Qiu, Qiong; Hernandez, Julio Cesar; Dean, Adam M.; Rao, Pulivarthi H.

2011-01-01

The identification of specific cell surface markers that can be used to isolate liver progenitor cells will greatly facilitate experimentation to determine the role of these cells in liver regeneration and their potential for therapeutic transplantation. Previously, the cell surface marker, CD24, was observed to be expressed on undifferentiated bipotential mouse embryonic liver stem cells and 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced oval cells. Here, we describe the isolation and characterization of a rare, primary, nonhematopoietic, CD24+ progenitor cell population from normal, untreated mouse liver. By immunohistochemistry, CD24-expressing cells in normal adult mouse liver were colocalized with CK19-positive cholangiocytes. This nonhematopoietic (CD45−, Ter119−) CD24+ cell population isolated by flow cytometry represented 0.04% of liver cells and expressed several markers of liver progenitor/oval cells. The immunophenotype of nonhematopoietic CD24+ cells was CD133, Dlk, and Sca-1 high, but c-Kit, Thy-1, and CD34 low. The CD24+ cells had increased expression of CK19, epithelial cell adhesion molecule, Sox 9, and FN14 compared with the unsorted cells. Upon transplantation of nonhematopoietic CD24+ cells under the sub-capsule of the livers of Fah knockout mice, cells differentiated into mature functional hepatocytes. Analysis of X and Y chromosome complements were used to determine whether or not fusion of the engrafted cells with the recipient hepatocytes occurred. No cells were found that contained XXXY or any other combination of donor and host sex chromosomes as would be expected if cell fusion had occurred. These results suggested that CD24 can be used as a cell surface marker for isolation of hepatocyte progenitor cells from normal adult liver that are able to differentiate into hepatocytes. PMID:21361791

CD24-positive cells from normal adult mouse liver are hepatocyte progenitor cells.

PubMed

Qiu, Qiong; Hernandez, Julio Cesar; Dean, Adam M; Rao, Pulivarthi H; Darlington, Gretchen J

2011-12-01

The identification of specific cell surface markers that can be used to isolate liver progenitor cells will greatly facilitate experimentation to determine the role of these cells in liver regeneration and their potential for therapeutic transplantation. Previously, the cell surface marker, CD24, was observed to be expressed on undifferentiated bipotential mouse embryonic liver stem cells and 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced oval cells. Here, we describe the isolation and characterization of a rare, primary, nonhematopoietic, CD24+ progenitor cell population from normal, untreated mouse liver. By immunohistochemistry, CD24-expressing cells in normal adult mouse liver were colocalized with CK19-positive cholangiocytes. This nonhematopoietic (CD45-, Ter119-) CD24+ cell population isolated by flow cytometry represented 0.04% of liver cells and expressed several markers of liver progenitor/oval cells. The immunophenotype of nonhematopoietic CD24+ cells was CD133, Dlk, and Sca-1 high, but c-Kit, Thy-1, and CD34 low. The CD24+ cells had increased expression of CK19, epithelial cell adhesion molecule, Sox 9, and FN14 compared with the unsorted cells. Upon transplantation of nonhematopoietic CD24+ cells under the sub-capsule of the livers of Fah knockout mice, cells differentiated into mature functional hepatocytes. Analysis of X and Y chromosome complements were used to determine whether or not fusion of the engrafted cells with the recipient hepatocytes occurred. No cells were found that contained XXXY or any other combination of donor and host sex chromosomes as would be expected if cell fusion had occurred. These results suggested that CD24 can be used as a cell surface marker for isolation of hepatocyte progenitor cells from normal adult liver that are able to differentiate into hepatocytes.

Neutrophils alleviate fibrosis in the CCl4-induced mouse chronic liver injury model.

PubMed

Saijou, Eiko; Enomoto, Yutaka; Matsuda, Michitaka; Yuet-Yin Kok, Cindy; Akira, Shizuo; Tanaka, Minoru; Miyajima, Atsushi

2018-06-01

Tribbles pseudokinase 1 ( Trib1 ) is a negative regulator of CCAAT/enhancer binding protein α (C/EBPα) and is known to induce granulopoiesis while suppressing monocyte differentiation. Loss of Trib1 was previously shown to increase the neutrophil population in the spleen but lead to M2-like macrophage reduction. Because M2 macrophages are anti-inflammatory and promote tissue repair by producing fibrogenic factors, we investigated liver fibrosis in Trib1 -deficient mice. Interestingly, loss of Trib1 suppressed fibrosis in the CCl 4 -induced chronic liver injury model. Trib1 knockout increased neutrophils but had a minimal effect on the macrophage population in the liver. Hepatic expressions of neutrophil matrix metalloproteinases ( Mmp ) 8 and Mmp9 were increased, but the production of fibrogenic factors, including transforming growth factor β1, was not affected by loss of Trib1 . These results suggest that neutrophils are responsible for the suppression of fibrosis in Trib1 -deficient liver. Consistently, transplantation of Trib1 -deficient bone marrow cells into wild-type mice alleviated CCl 4 -induced fibrosis. Furthermore, expression of chemokine (C-X-C motif) ligand 1 ( Cxcl1 ) by adeno-associated viral vector in the normal liver recruited neutrophils and suppressed CCl 4 -induced fibrosis; infusion of wild-type neutrophils in CCl 4 -treated mice also ameliorated fibrosis. Using recombinant adeno-associated virus-mediated expression of Mmp8 and Mmp9 alleviated liver fibrosis. Finally, neutrophil depletion by infusion of Ly6G antibody significantly enhanced CCl 4 -induced fibrosis. Conclusion : While neutrophils are well known to exacerbate acute liver injury, our results demonstrate a beneficial role of neutrophils in chronic liver injury by promoting fibrolysis. ( Hepatology Communications 2018;2:703-717).

Cannabidiol protects liver from binge alcohol-induced steatosis by mechanisms including inhibition of oxidative stress and increase in autophagy

PubMed Central

Yang, Lili; Rozenfeld, Raphael; Wu, Defeng; Devi, Lakshmi A.; Zhang, Zhenfeng; Cederbaum, Arthur

2014-01-01

Acute alcohol drinking induces steatosis, and effective prevention of steatosis can protect liver from progressive damage caused by alcohol. Increased oxidative stress has been reported as one mechanism underlying alcohol-induced steatosis. We evaluated whether cannabidiol, which has been reported to function as an antioxidant, can protect the liver from alcohol-generated oxidative stress-induced steatosis. Cannabidiol can prevent acute alcohol-induced liver steatosis in mice, possibly by preventing the increase in oxidative stress and the activation of the JNK MAPK pathway. Cannabidiol per se can increase autophagy both in CYP2E1-expressing HepG2 cells and in mouse liver. Importantly, cannabidiol can prevent the decrease in autophagy induced by alcohol. In conclusion, these results show that cannabidiol protects mouse liver from acute alcohol-induced steatosis through multiple mechanisms including attenuation of alcohol-mediated oxidative stress, prevention of JNK MAPK activation, and increasing autophagy. PMID:24398069

Optimized Mouse Models for Liver Fibrosis.

PubMed

Kim, Yong Ook; Popov, Yury; Schuppan, Detlef

2017-01-01

Fibrosis is the excessive accumulation of extracellular matrix components due to chronic injury, with collagens as predominant structural components. Liver fibrosis can progress to cirrhosis, which is characterized by a severe distortion of the delicate hepatic vascular architecture, the shunting of the blood supply away from hepatocytes and the resultant functional liver failure. Cirrhosis is associated with a highly increased morbidity and mortality and represents the major hard endpoint in clinical studies of chronic liver diseases. Moreover, cirrhosis is a strong cofactor of primary liver cancer. In vivo models are indispensable tools to study the cellular and molecular mechanisms of liver fibrosis and to develop specific antifibrotic therapies towards clinical translation. Here, we provide a detailed description of select optimized mouse models of liver fibrosis and state-of-the-art fibrosis readouts.

TWEAK induces liver progenitor cell proliferation

PubMed Central

Jakubowski, Aniela; Ambrose, Christine; Parr, Michael; Lincecum, John M.; Wang, Monica Z.; Zheng, Timothy S.; Browning, Beth; Michaelson, Jennifer S.; Baestcher, Manfred; Wang, Bruce; Bissell, D. Montgomery; Burkly, Linda C.

2005-01-01

Progenitor (“oval”) cell expansion accompanies many forms of liver injury, including alcohol toxicity and submassive parenchymal necrosis as well as experimental injury models featuring blocked hepatocyte replication. Oval cells can potentially become either hepatocytes or biliary epithelial cells and may be critical to liver regeneration, particularly when hepatocyte replication is impaired. The regulation of oval cell proliferation is incompletely understood. Herein we present evidence that a TNF family member called TWEAK (TNF-like weak inducer of apoptosis) stimulates oval cell proliferation in mouse liver through its receptor Fn14. TWEAK has no effect on mature hepatocytes and thus appears to be selective for oval cells. Transgenic mice overexpressing TWEAK in hepatocytes exhibit periportal oval cell hyperplasia. A similar phenotype was obtained in adult wild-type mice, but not Fn14-null mice, by administering TWEAK-expressing adenovirus. Oval cell expansion induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) was significantly reduced in Fn14-null mice as well as in adult wild-type mice with a blocking anti-TWEAK mAb. Importantly, TWEAK stimulated the proliferation of an oval cell culture model. Finally, we show increased Fn14 expression in chronic hepatitis C and other human liver diseases relative to its expression in normal liver, which suggests a role for the TWEAK/Fn14 pathway in human liver injury. We conclude that TWEAK has a selective mitogenic effect for liver oval cells that distinguishes it from other previously described growth factors. PMID:16110324

Gene expression profile change and associated physiological and pathological effects in mouse liver induced by fasting and refeeding.

PubMed

Zhang, Fang; Xu, Xiang; Zhou, Ben; He, Zhishui; Zhai, Qiwei

2011-01-01

Food availability regulates basal metabolism and progression of many diseases, and liver plays an important role in these processes. The effects of food availability on digital gene expression profile, physiological and pathological functions in liver are yet to be further elucidated. In this study, we applied high-throughput sequencing technology to detect digital gene expression profile of mouse liver in fed, fasted and refed states. Totally 12162 genes were detected, and 2305 genes were significantly regulated by food availability. Biological process and pathway analysis showed that fasting mainly affected lipid and carboxylic acid metabolic processes in liver. Moreover, the genes regulated by fasting and refeeding in liver were mainly enriched in lipid metabolic process or fatty acid metabolism. Network analysis demonstrated that fasting mainly regulated Drug Metabolism, Small Molecule Biochemistry and Endocrine System Development and Function, and the networks including Lipid Metabolism, Small Molecule Biochemistry and Gene Expression were affected by refeeding. In addition, FunDo analysis showed that liver cancer and diabetes mellitus were most likely to be affected by food availability. This study provides the digital gene expression profile of mouse liver regulated by food availability, and demonstrates the main biological processes, pathways, gene networks and potential hepatic diseases regulated by fasting and refeeding. These results show that food availability mainly regulates hepatic lipid metabolism and is highly correlated with liver-related diseases including liver cancer and diabetes.

Multifaceted Therapeutic Benefits of Factors Derived From Dental Pulp Stem Cells for Mouse Liver Fibrosis.

PubMed

Hirata, Marina; Ishigami, Masatoshi; Matsushita, Yoshihiro; Ito, Takanori; Hattori, Hisashi; Hibi, Hideharu; Goto, Hidemi; Ueda, Minoru; Yamamoto, Akihito

2016-10-01

: Chronic liver injury from various causes often results in liver fibrosis (LF). Although the liver possesses endogenous tissue-repairing activities, these can be overcome by sustained inflammation and excessive fibrotic scar formation. Advanced LF leads to irreversible cirrhosis and subsequent liver failure and/or hepatic cancer. Here, using the mouse carbon tetrachloride (CCl 4 )-induced LF model, we showed that a single intravenous administration of stem cells derived from human exfoliated deciduous teeth (SHEDs) or of SHED-derived serum-free conditioned medium (SHED-CM) resulted in fibrotic scar resolution. SHED-CM suppressed the gene expression of proinflammatory mediators, such as TNF-α, IL-1β, and iNOS, and eliminated activated hepatic stellate cells by inducing their apoptosis, but protected parenchymal hepatocytes from undergoing apoptosis. In addition, SHED-CM induced tissue-repairing macrophages that expressed high levels of the profibrinolytic factor, matrix metalloproteinase 13. Furthermore, SHED-CM suppressed the CCl 4 -induced apoptosis of primary cultured hepatocytes. SHED-CM contained a high level of hepatocyte growth factor (HGF). Notably, HGF-depleted SHED-CM (dHGF-CM) did not suppress the proinflammatory response or resolve fibrotic scarring. Furthermore, SHED-CM, but not dHGF-CM, inhibited CCl 4 -induced hepatocyte apoptosis. These results suggest that HGF plays a central role in the SHED-CM-mediated resolution of LF. Taken together, our findings suggest that SHED-CM provides multifaceted therapeutic benefits for the treatment of LF. This study demonstrated that a single intravenous administration of stem cells from human exfoliated deciduous teeth (SHEDs) or of the serum-free conditioned medium (CM) derived from SHEDs markedly improved mouse liver fibrosis (LF). SHED-CM suppressed chronic inflammation, eliminated activated hepatic stellate cells by inducing their apoptosis, protected hepatocytes from undergoing apoptosis, and induced

A mouse model of mitochondrial complex III dysfunction induced by myxothiazol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davoudi, Mina; Kallijärvi, Jukka; Marjavaara, Sanna

2014-04-18

Highlights: • Reversible chemical inhibition of complex III in wild type mouse. • Myxothiazol causes decreased complex III activity in mouse liver. • The model is useful for therapeutic trials to improve mitochondrial function. - Abstract: Myxothiazol is a respiratory chain complex III (CIII) inhibitor that binds to the ubiquinol oxidation site Qo of CIII. It blocks electron transfer from ubiquinol to cytochrome b and thus inhibits CIII activity. It has been utilized as a tool in studies of respiratory chain function in in vitro and cell culture models. We developed a mouse model of biochemically induced and reversible CIIImore » inhibition using myxothiazol. We administered myxothiazol intraperitoneally at a dose of 0.56 mg/kg to C57Bl/J6 mice every 24 h and assessed CIII activity, histology, lipid content, supercomplex formation, and gene expression in the livers of the mice. A reversible CIII activity decrease to 50% of control value occurred at 2 h post-injection. At 74 h only minor histological changes in the liver were found, supercomplex formation was preserved and no significant changes in the expression of genes indicating hepatotoxicity or inflammation were found. Thus, myxothiazol-induced CIII inhibition can be induced in mice for four days in a row without overt hepatotoxicity or lethality. This model could be utilized in further studies of respiratory chain function and pharmacological approaches to mitochondrial hepatopathies.« less

KEAP1-NRF2 COMPLEX IN ISCHEMIA-INDUCED HEPATOCELLULAR DAMAGE OF MOUSE LIVER TRANSPLANTS

PubMed Central

Ke, Bibo; Shen, Xiu-Da; Zhang, Yu; Ji, Haofeng; Gao, Feng; Yue, Shi; Kamo, Naoko; Zhai, Yuan; Yamamoto, Masayuki; Busuttil, Ronald W.; Kupiec-Weglinski, Jerzy W.

2015-01-01

Background The Keap1-Nrf2 signaling pathway regulates host cell defense responses against oxidative stress and maintains the cellular redox balance. Aims&Methods: We investigated the function/molecular mechanisms by which Keap1-Nrf2 complex may influence liver ischemia/reperfusion injury (IRI) in a mouse model of hepatic cold storage (20h at 4 C) followed by orthotopic liver transplantation (OLT). Results The Keap1 hepatocyte-specific knock-out (HKO) in the donor liver ameliorated post-transplant IRI, evidenced by improved hepatocellular function and OLT outcomes (Keap1HKO Keap1HKO; 100% survival), as compared with controls (WT WT; 50% survival; p<0.01). In contrast, donor liver Nrf2 deficiency exacerbated IRI in transplant recipients (Nrf2KO Nrf2KO; 40% survival). Ablation of Keap1 signaling reduced macrophage/neutrophil trafficking, pro-inflammatory cytokine programs, and hepatocellular necrosis/apoptosis, while simultaneously promoting anti-apoptotic functions in OLTs. At the molecular level, Keap1HKO increased Nrf2 levels, stimulated Akt phosphorylation, and enhanced expression of anti-oxidant Trx1, HIF-1 , and HO-1. Pretreatment of liver donors with PI3K inhibitor (LY294002) disrupted Akt/HIF-1 signaling and recreated hepatocellular damage in otherwise IR-resistant Keap1HKO transplants. In parallel in vitro studies, hydrogen peroxide-stressed Keap1-deficient hepatocytes were characterized by enhanced expression of Nrf2, Trx1, and Akt phosphorylation, in association with decreased release of lactate dehydrogenase (LDH) in cell culture supernatants. Conclusions Keap1-Nrf2 complex prevents oxidative injury in IR-stressed OLTs through Keap1 signaling, which negatively regulates Nrf2 pathway. Activation of Nrf2 induces Trx1 and promotes PI3K/Akt, crucial for HIF-1 activity. HIF-1 -mediated overexpression of HO-1/CyclinD1 facilitates cytoprotection by limiting hepatic inflammatory responses, and hepatocellular necrosis/apoptosis in PI3K-dependent manner. PMID

Targeted Induction of Interferon-λ in Humanized Chimeric Mouse Liver Abrogates Hepatotropic Virus Infection

PubMed Central

Kameyama, Takeshi; Tokunaga, Yuko; Nishito, Yasumasa; Hirabayashi, Kazuko; Yano, Junichi; Ochiya, Takahiro; Tateno, Chise; Tanaka, Yasuhito; Mizokami, Masashi; Tsukiyama-Kohara, Kyoko; Inoue, Kazuaki; Yoshiba, Makoto; Takaoka, Akinori; Kohara, Michinori

2013-01-01

Background & Aims The interferon (IFN) system plays a critical role in innate antiviral response. We presume that targeted induction of IFN in human liver shows robust antiviral effects on hepatitis C virus (HCV) and hepatitis B virus (HBV). Methods This study used chimeric mice harboring humanized livers and infected with HCV or HBV. This mouse model permitted simultaneous analysis of immune responses by human and mouse hepatocytes in the same liver and exploration of the mechanism of antiviral effect against these viruses. Targeted expression of IFN was induced by treating the animals with a complex comprising a hepatotropic cationic liposome and a synthetic double-stranded RNA analog, pIC (LIC-pIC). Viral replication, IFN gene expression, IFN protein production, and IFN antiviral activity were analyzed (for type I, II and III IFNs) in the livers and sera of these humanized chimeric mice. Results Following treatment with LIC-pIC, the humanized livers of chimeric mice exhibited increased expression (at the mRNA and protein level) of human IFN-λs, resulting in strong antiviral effect on HBV and HCV. Similar increases were not seen for human IFN-α or IFN-β in these animals. Strong induction of IFN-λs by LIC-pIC occurred only in human hepatocytes, and not in mouse hepatocytes nor in human cell lines derived from other (non-hepatic) tissues. LIC-pIC-induced IFN-λ production was mediated by the immune sensor adaptor molecules mitochondrial antiviral signaling protein (MAVS) and Toll/IL-1R domain-containing adaptor molecule-1 (TICAM-1), suggesting dual recognition of LIC-pIC by both sensor adaptor pathways. Conclusions These findings demonstrate that the expression and function of various IFNs differ depending on the animal species and tissues under investigation. Chimeric mice harboring humanized livers demonstrate that IFN-λs play an important role in the defense against human hepatic virus infection. PMID:23555725

Neutrophils alleviate fibrosis in the CCl4‐induced mouse chronic liver injury model

PubMed Central

Saijou, Eiko; Enomoto, Yutaka; Matsuda, Michitaka; Yuet‐Yin Kok, Cindy; Akira, Shizuo; Tanaka, Minoru

2018-01-01

Tribbles pseudokinase 1 (Trib1) is a negative regulator of CCAAT/enhancer binding protein α (C/EBPα) and is known to induce granulopoiesis while suppressing monocyte differentiation. Loss of Trib1 was previously shown to increase the neutrophil population in the spleen but lead to M2‐like macrophage reduction. Because M2 macrophages are anti‐inflammatory and promote tissue repair by producing fibrogenic factors, we investigated liver fibrosis in Trib1‐deficient mice. Interestingly, loss of Trib1 suppressed fibrosis in the CCl4‐induced chronic liver injury model. Trib1 knockout increased neutrophils but had a minimal effect on the macrophage population in the liver. Hepatic expressions of neutrophil matrix metalloproteinases (Mmp)8 and Mmp9 were increased, but the production of fibrogenic factors, including transforming growth factor β1, was not affected by loss of Trib1. These results suggest that neutrophils are responsible for the suppression of fibrosis in Trib1‐deficient liver. Consistently, transplantation of Trib1‐deficient bone marrow cells into wild‐type mice alleviated CCl4‐induced fibrosis. Furthermore, expression of chemokine (C‐X‐C motif) ligand 1 (Cxcl1) by adeno‐associated viral vector in the normal liver recruited neutrophils and suppressed CCl4‐induced fibrosis; infusion of wild‐type neutrophils in CCl4‐treated mice also ameliorated fibrosis. Using recombinant adeno‐associated virus‐mediated expression of Mmp8 and Mmp9 alleviated liver fibrosis. Finally, neutrophil depletion by infusion of Ly6G antibody significantly enhanced CCl4‐induced fibrosis. Conclusion: While neutrophils are well known to exacerbate acute liver injury, our results demonstrate a beneficial role of neutrophils in chronic liver injury by promoting fibrolysis. (Hepatology Communications 2018;2:703‐717) PMID:29881822

Garlic extract diallyl sulfide (DAS) activates nuclear receptor CAR to induce the Sult1e1 gene in mouse liver.

PubMed

Sueyoshi, Tatsuya; Green, William D; Vinal, Kellie; Woodrum, Tyler S; Moore, Rick; Negishi, Masahiko

2011-01-01

Constituent chemicals in garlic extract are known to induce phase I and phase II enzymes in rodent livers. Here we have utilized Car(+/+) and Car(-/-) mice to demonstrate that the nuclear xenobiotic receptor CAR regulated the induction of the estrogen sulfotransferase Sult1e1 gene by diallyl sulfide (DAS) treatment in mouse liver. DAS treatment caused CAR accumulation in the nucleus, resulting in a remarkable increase of SULT1E1 mRNA (3,200 fold) and protein in the livers of Car(+/+) females but not of Car(-/-) female mice. DAS also induced other CAR-regulated genes such as Cyp2b10, Cyp3a11 and Gadd45β. Compared with the rapid increase of these mRNA levels, which began as early as 6 hours after DAS treatment, the levels of SULT1E1 mRNA began increasing after 24 hours. This slow response to DAS suggested that CAR required an additional factor to activate the Sult1e1 gene or that this activation was indirect. Despite the remarkable induction of SULT1E1, there was no decrease in the serum levels of endogenous E2 or increase of estrone sulfate while the clearance of exogenously administrated E2 was accelerated in DAS treated mice.

Gene Expression Profile Change and Associated Physiological and Pathological Effects in Mouse Liver Induced by Fasting and Refeeding

PubMed Central

Zhang, Fang; Xu, Xiang; Zhou, Ben; He, Zhishui; Zhai, Qiwei

2011-01-01

Food availability regulates basal metabolism and progression of many diseases, and liver plays an important role in these processes. The effects of food availability on digital gene expression profile, physiological and pathological functions in liver are yet to be further elucidated. In this study, we applied high-throughput sequencing technology to detect digital gene expression profile of mouse liver in fed, fasted and refed states. Totally 12162 genes were detected, and 2305 genes were significantly regulated by food availability. Biological process and pathway analysis showed that fasting mainly affected lipid and carboxylic acid metabolic processes in liver. Moreover, the genes regulated by fasting and refeeding in liver were mainly enriched in lipid metabolic process or fatty acid metabolism. Network analysis demonstrated that fasting mainly regulated Drug Metabolism, Small Molecule Biochemistry and Endocrine System Development and Function, and the networks including Lipid Metabolism, Small Molecule Biochemistry and Gene Expression were affected by refeeding. In addition, FunDo analysis showed that liver cancer and diabetes mellitus were most likely to be affected by food availability. This study provides the digital gene expression profile of mouse liver regulated by food availability, and demonstrates the main biological processes, pathways, gene networks and potential hepatic diseases regulated by fasting and refeeding. These results show that food availability mainly regulates hepatic lipid metabolism and is highly correlated with liver-related diseases including liver cancer and diabetes. PMID:22096593

Human Umbilical Cord MSC-Derived Exosomes Suppress the Development of CCl4-Induced Liver Injury through Antioxidant Effect.

PubMed

Jiang, Wenqian; Tan, Youwen; Cai, Mengjie; Zhao, Ting; Mao, Fei; Zhang, Xu; Xu, Wenrong; Yan, Zhixin; Qian, Hui; Yan, Yongmin

2018-01-01

Mesenchymal stem cells (MSCs) have been increasingly applied into clinical therapy. Exosomes are small (30-100 nm in diameter) membrane vesicles released by different cell types and possess the similar functions with their derived cells. Human umbilical cord MSC-derived exosomes (hucMSC-Ex) play important roles in liver repair. However, the effects and mechanisms of hucMSC-Ex on liver injury development remain elusive. Mouse models of acute and chronic liver injury and liver tumor were induced by carbon tetrachloride (CCl 4 ) injection, followed by administration of hucMSC-Ex via the tail vein. Alleviation of liver injury by hucMSC-Ex was determined. We further explored the production of oxidative stress and apoptosis in the development of liver injury and compared the antioxidant effects of hucMSC-Ex with frequently used hepatic protectant, bifendate (DDB) in liver injury. hucMSC-Ex alleviated CCl 4 -induced acute liver injury and liver fibrosis and restrained the growth of liver tumors. Decreased oxidative stress and apoptosis were found in hucMSC-Ex-treated mouse models and liver cells. Compared to bifendate (DDB) treatment, hucMSC-Ex presented more distinct antioxidant and hepatoprotective effects. hucMSC-Ex may suppress CCl 4 -induced liver injury development via antioxidant potentials and could be a more effective antioxidant than DDB in CCl 4 -induced liver tumor development.

Lack of gp130 expression in hepatocytes attenuates tumor progression in the DEN model.

PubMed

Hatting, M; Spannbauer, M; Peng, J; Al Masaoudi, M; Sellge, G; Nevzorova, Y A; Gassler, N; Liedtke, C; Cubero, F J; Trautwein, C

2015-03-05

Chronic liver inflammation is a crucial event in the development and growth of hepatocellular carcinoma (HCC). Compelling evidence has shown that interleukin-6 (IL-6)/gp130-dependent signaling has a fundamental role in liver carcinogenesis. Thus, in the present study we aimed to investigate the role of gp130 in hepatocytes for the initiation and progression of HCC. Hepatocyte-specific gp130 knockout mice (gp130(Δhepa)) and control animals (gp130(f/f)) were treated with diethylnitrosamine (DEN). The role of gp130 for acute injury (0-144 h post treatment), tumor initiation (24 weeks) and progression (40 weeks) was analyzed. After acute DEN-induced liver injury we observed a reduction in the inflammatory response in gp130(Δhepa) animals as reflected by decreased levels of IL-6 and oncostatin M. The loss of gp130 slightly attenuated the initiation of HCC 24 weeks after DEN treatment. In contrast, 40 weeks after DEN treatment, male and female gp130(Δhepa) mice showed smaller tumors and reduced tumor burden, indicating a role for hepatocyte-specific gp130 expression during HCC progression. Oxidative stress and DNA damage were substantially and similarly increased by DEN in both gp130(f/f) and gp130(Δhepa) animals. However, gp130(Δhepa) livers revealed aberrant STAT5 activation and decreased levels of transforming growth factor-β (TGFβ), pSMAD2/3 and SMAD2, whereas phosphorylation of STAT3 at Tyr705 and Ser727 was absent. Our results indicate that gp130 deletion in hepatocytes reduces progression, but not HCC initiation in the DEN model. Gp130 deletion resulted in STAT3 inhibition but increased STAT5 activation and diminished TGF-dependent signaling. Hence, blocking gp130 in hepatocytes might be an interesting therapeutic target to inhibit the growth of HCC.

Extracellular deposition of mouse senile AApoAII amyloid fibrils induced different unfolded protein responses in the liver, kidney, and heart.

PubMed

Luo, Hongmin; Sawashita, Jinko; Tian, Geng; Liu, Yingye; Li, Lin; Ding, Xin; Xu, Zhe; Yang, Mu; Miyahara, Hiroki; Mori, Masayuki; Qian, Jinze; Wang, Yaoyong; Higuchi, Keiichi

2015-03-01

Mouse senile amyloidosis is a disorder in which apolipoprotein A-II deposits extracellularly in many organs as amyloid fibrils (AApoAII). In this study, we intravenously injected 1 μg of isolated AApoAII fibrils into R1.P1-Apoa2(c) mice, to induce AApoAII amyloidosis. We observed that the unfolded protein response was induced by deposition of AApoAII amyloid. We found that the mRNA and the protein expression levels of heat shock protein A5 (HSPA5; also known as glucose-regulated protein 78) were increased in the liver with AApoAII amyloid deposits. Immunohistochemistry showed that HSPA5 was only detected in hepatocytes close to AApoAII amyloid deposits. Furthermore, gene transcription of several endoplasmic reticulum (ER) stress-related proteins increased, including eukaryotic translation initiation factor 2 alpha kinase 3 (Eif2ak3), activating transcription factor 6 (Atf6), activating transcription factor 4 (Atf4), X-box-binding protein 1 splicing (Xbp1s), DNA-damage inducible transcript 3 (Ddit3), and autophagy protein 5 (Atg5). Moreover, apoptosis-positive cells were increased in the liver. Similar results were seen in the kidney but not in the heart. Our study indicates that ER stress responses differed among tissues with extracellular AApoAII amyloid fibril deposition. Although upregulated HSPA5 and the activated unfolded protein response might have roles in protecting tissues against aggregated extracellular AApoAII amyloid deposition, prolonged ER stress induced apoptosis in the liver and the kidney.

A potential microRNA signature for tumorigenic conazoles in mouse liver.

PubMed

Ross, Jeffrey A; Blackman, Carl F; Thai, Sheau-Fung; Li, Zhiguang; Kohan, Michael; Jones, Carlton P; Chen, Tao

2010-04-01

Triadimefon, propiconazole, and myclobutanil are conazoles, an important class of agricultural fungicides. Triadimefon and propiconazole are mouse liver tumorigens, while myclobutanil is not. As part of a coordinated study to understand the molecular determinants of conazole tumorigenicity, we analyzed the microRNA expression levels in control and conazole-treated mice after 90 d of administration in feed. MicroRNAs (miRNAs) are small noncoding RNAs composed of approximately 19-24 nucleotides in length, and have been shown to interact with mRNA (usually 3' UTR) to suppress its expression. MicroRNAs play a key role in diverse biological processes, including development, cell proliferation, differentiation, and apoptosis. Groups of mice were fed either control diet or diet containing 1800 ppm triadimefon, 2500 ppm propiconazole, or 2000 ppm myclobutanil. MicroRNA was isolated from livers and analyzed using Superarray whole mouse genome miRNA PCR arrays from SABioscience. Data were analyzed using the significance analysis of microarrays (SAM) procedure. We identified those miRNAs whose expression was either increased or decreased relative to untreated controls with q < or = 0.01. The tumorigenic conazoles induced many more changes in miRNA expression than the nontumorigenic conazole. A group of 19 miRNAs was identified whose expression was significantly altered in both triadimefon- and propiconazole-treated animals but not in myclobutanil-treated animals. All but one of the altered miRNAs were downregulated compared to controls. This pattern of altered miRNA expression may represent a signature for tumorigenic conazole exposure in mouse liver after 90 d of treatment.

Clock gene Per2 as a controller of liver carcinogenesis

PubMed Central

Mteyrek, Ali; Filipski, Elisabeth; Guettier, Catherine; Okyar, Alper; Lévi, Francis

2016-01-01

Environmental disruption of molecular clocks promoted liver carcinogenesis and accelerated cancer progression in rodents. We investigated the specific role of clock gene Period 2 (Per2) for liver carcinogenesis and clock-controlled cellular proliferation, genomic instability and inflammation. We assessed liver histopathology, and determined molecular and physiology circadian patterns in mice on chronic diethylnitrosamine (DEN) exposure according to constitutive Per2 mutation. First, we found that Per2m/m liver displayed profound alterations in proliferation gene expression, including c-Myc derepression, phase-advanced Wee1, and arrhythmic Ccnb1 and K-ras mRNA expressions, as well as deregulated inflammation, through arrhythmic liver IL-6 protein concentration, in the absence of any DEN exposure. These changes could then make Per2m/m mice more prone to subsequently develop liver cancers on DEN. Indeed, primary liver cancers were nearly fourfold as frequent in Per2m/m mice as compared to wild-type (WT), 4 months after DEN exposure. The liver molecular clock was severely disrupted throughout the whole carcinogenesis process, including the initiation stage, i.e. within the initial 17 days on DEN. Per2m/m further exhibited increased c-Myc and Ccnb1 mean 24h expressions, lack of P53 response, and arrhythmic ATM, Wee1 and Ccnb1 expressions. DEN-induced tumor related inflammation was further promoted through increased protein concentrations of liver IL-6 and TNF-α as compared to WT during carcinogenesis initiation. Per2 mutation severely deregulated liver gene or protein expressions related to three cancer hallmarks, including uncontrolled proliferation, genomic instability, and tumor promoting inflammation, and accelerated liver carcinogenesis several-fold. Clock gene Per2 acted here as a liver tumor suppressor from initiation to progression. PMID:27494874

Lactobacillus rhamnosus GG culture supernatant ameliorates acute alcohol-induced intestinal permeability and liver injury

PubMed Central

Wang, Yuhua; Liu, Yanlong; Sidhu, Anju; Ma, Zhenhua; McClain, Craig

2012-01-01

Endotoxemia is a contributing cofactor to alcoholic liver disease (ALD), and alcohol-induced increased intestinal permeability is one of the mechanisms of endotoxin absorption. Probiotic bacteria have been shown to promote intestinal epithelial integrity and protect barrier function in inflammatory bowel disease (IBD) and in ALD. Although it is highly possible that some common molecules secreted by probiotics contribute to this action in IBD, the effect of probiotic culture supernatant has not yet been studied in ALD. We examined the effects of Lactobacillus rhamnosus GG culture supernatant (LGG-s) on the acute alcohol-induced intestinal integrity and liver injury in a mouse model. Mice on standard chow diet were supplemented with supernatant from LGG culture (109 colony-forming unit/mouse) for 5 days, and one dose of alcohol at 6 g/kg body wt was administered via gavage. Intestinal permeability was measured by FITC-FD-4 ex vivo. Alcohol-induced liver injury was examined by measuring the activity of alanine aminotransferase (ALT) in plasma, and liver steatosis was evaluated by triglyceride content and Oil Red O staining of the liver sections. LGG-s pretreatment restored alcohol-induced reduction in ileum mRNA levels of claudin-1, intestine trefoil factor (ITF), P-glycoprotein (P-gp), and cathelin-related antimicrobial peptide (CRAMP), which play important roles on intestinal barrier integrity. As a result, LGG-s pretreatment significantly inhibited the alcohol-induced intestinal permeability, endotoxemia and subsequently liver injury. Interestingly, LGG-s pretreatment increased ileum mRNA expression of hypoxia-inducible factor (HIF)-2α, an important transcription factor of ITF, P-gp, and CRAMP. These results suggest that LGG-s ameliorates the acute alcohol-induced liver injury by promoting HIF signaling, leading to the suppression of alcohol-induced increased intestinal permeability and endotoxemia. The use of bacteria-free LGG culture supernatant provides a novel

Interaction of acute-phase-inducible and liver-enriched nuclear factors with the promoter region of the mouse alpha sub 1 -acid glycoprotein gene-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alam, T.; Papaconstantinou, J.

1992-02-25

The synthesis and secretion of several acute-phase proteins increases markedly following physiological stress. {alpha}{sub 1}-Acid glycoprotein (AGP), a major acute-phase reactant made by the liver, is strongly induced by inflammatory agents such as lipopolysaccharide (LPS). Nuclear run-on assay showed a 17-fold increase in the rate of AGP transcription 4 h following LPS injection. DNase I footprinting assays revealed multiple protein binding domains in the mouse AGP-1 promoter region. Region B ({minus}104 to {minus}91) is protected by a liver-enriched transcription factor that is heat labile and in limiting quantity. An adjacent region, C ({minus}125 to {minus}104), is well-protected by nuclear extractsmore » from hepatocytes. Electrophoretic mobility shift assays indicated that only one DNA-protein complex can form with an oligonucleotide corresponding to region B. However, nuclear proteins from untreated mouse liver can form three strong complexes (C1, C2, and C3) and a weak one (C4) with oligonucleotide C. An acute-phase-inducible DNA-binding protein (AP-DBP) forms complex 4. A dramatic increase (over 11-fold) in AP-DBP binding activity is seen with nuclear proteins from LPS-stimulated animals. Interestingly, AP-DBP, a heat-stable factor, can form heterodimers with the transcription factor CCAAT/enhancer binding protein (C/EBP). Furthermore, purified C/EBP also binds avidly to region C. The studies indicate that several liver-enriched nuclear factors can interact with AGP-1 promoter and that AP-DBP binds to the AGP-1 promoter with high affinity only during the acute-phase induction.« less

Extract of Ginkgo biloba exacerbates liver metastasis in a mouse colon cancer Xenograft model.

PubMed

Wang, Huan; Wu, Xia; Lezmi, Stephane; Li, Qian; Helferich, William G; Xu, Yueqing; Chen, Hong

2017-12-02

Metastasis refers to the spread of a primary tumor cell from the primary site to other locations in the body and it is generally associated with the severity of a tumor. Extract of Ginkgo biloba (EGb) contains various bioactive compounds and it exerts beneficial effects including improvements in brain function and reduced risk of cardiovascular diseases. On the other hand, increased risk of thyroid and liver cancers by EGb have been reported in animals. A colon cancer metastasis model was established using intrasplenic injection of a human colon cancer cell line, SW620-luc in athymic mice to investigate the potential impact of EGb on colon cancer progression. After tumor establishment, EGb was intraperitonically injected daily for 5 wks. EGb significantly increased the rate of metastasis in mouse liver and decreased the number of necrotic and apoptotic cells in the metastatic liver when compared to the control. Meanwhile, EGb significantly induced proliferation of tumor cells in the metastatic liver, indicated by increased staining of Ki67 and H3S10p. mRNA expression of genes involved in cell cycle, metastasis, apoptosis, and oxidative stress were altered by EGb treatment in livers with tumors. Moreover, EGb activated the stress-responsive MAPK pathways in the liver with metastatic tumors. EGb exacerbated liver metastasis in a mouse colon cancer metastasis model. This is potentially due to the increased tumor cell proliferation involving stimulated MAPK pathways.

Garlic Extract Diallyl Sulfide (DAS) Activates Nuclear Receptor CAR to Induce the Sult1e1 Gene in Mouse Liver

PubMed Central

Sueyoshi, Tatsuya; Green, William D.; Vinal, Kellie; Woodrum, Tyler S.; Moore, Rick; Negishi, Masahiko

2011-01-01

Constituent chemicals in garlic extract are known to induce phase I and phase II enzymes in rodent livers. Here we have utilized Car +/+ and Car −/− mice to demonstrate that the nuclear xenobiotic receptor CAR regulated the induction of the estrogen sulfotransferase Sult1e1 gene by diallyl sulfide (DAS) treatment in mouse liver. DAS treatment caused CAR accumulation in the nucleus, resulting in a remarkable increase of SULT1E1 mRNA (3,200 fold) and protein in the livers of Car +/+ females but not of Car −/− female mice. DAS also induced other CAR-regulated genes such as Cyp2b10, Cyp3a11 and Gadd45β. Compared with the rapid increase of these mRNA levels, which began as early as 6 hourrs after DAS treatment, the levels of SULT1E1 mRNA began increasing after 24 hours. This slow response to DAS suggested that CAR required an additional factor to activate the Sult1e1 gene or that this activation was indirect. Despite the remarkable induction of SULT1E1, there was no decrease in the serum levels of endogenous E2 or increase of estrone sulfate while the clearance of exogenously administrated E2 was accelerated in DAS treated mice. PMID:21698271

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santra, Amal; Chowdhury, Abhijit; Ghatak, Subhadip

2007-04-15

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.more » 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.« less

Study of in vivo exposure of single-walled carbon nanotubes in mouse liver

NASA Astrophysics Data System (ADS)

Lyons, Lyndon L.

Currently, few studies are available that have explored the role of carbon nanoparticles in liver toxicity. The susceptibility of the liver to nanoparticles rises from the inhalation exposure route often encountered during manufacturing and occupational exposure. Persons occupying these types of environmental setting are exposed to airborne nanoparticles less than 100nm, which have unobstructed access to most area of the lungs due to their size. Several reports have shown that single walled carbon nanotubes (SWCNTs) induce oxidative stress and pose the greatest cytotoxicity potential do to their size. Also, studies in mice indicate nanoparticles tend to accumulate in organs such as the spleen, kidney and liver, which is a major concern due to a lack of knowledge as to their fate. Single Wall Carbon Nanotubes (SWCNT's) are able to more easily penetrate through the cell membrane and display higher cell toxicity than Multi walled carbon nanotubes (MWCTs), opening the possibility for crossing various biological barriers within the body. Therefore effective occupational and environmental health risk assessments are significant in controlling the manufacture process of carbon nanotubes (CNTs). The present study was undertaken to determine the toxicity exhibited by SWCNT in mouse liver tissue as a model system. Mouse exposure during inhalation with and without SWCNT and reactive oxygen species (ROS) products were measured by change in fluorescence using dichloro fluorescein (DCF). The result showed no increase ROS on exposure of SWCNT in a dose and time dependent manner. Also, there is no reduction levels of glutathione (GSH) and super oxide dismutase (SOD), the antioxidant protective mechanism present in mouse liver cells upon SWCNT exposure. Lipid Peroxidation (LPO) and Lactate Dehydrogenase (LDH) assays indicated no tissue or protein damage. Additionally, Caspases --8 and --3 assays were conducted in order to understand the apoptotic signaling pathways initiated by

Sex-specific metabolic interactions between liver and adipose tissue in MCD diet-induced non-alcoholic fatty liver disease.

PubMed

Lee, Yun-Hee; Kim, Sou Hyun; Kim, Sang-Nam; Kwon, Hyun-Jung; Kim, Jeong-Dong; Oh, Ji Youn; Jung, Young-Suk

2016-07-26

Higher susceptibility to metabolic disease in male exemplifies the importance of sexual dimorphism in pathogenesis. We hypothesized that the higher incidence of non-alcoholic fatty liver disease in males involves sex-specific metabolic interactions between liver and adipose tissue. In the present study, we used a methionine-choline deficient (MCD) diet-induced fatty liver mouse model to investigate sex differences in the metabolic response of the liver and adipose tissue. After 2 weeks on an MCD-diet, fatty liver was induced in a sex-specific manner, affecting male mice more severely than females. The MCD-diet increased lipolytic enzymes in the gonadal white adipose tissue (gWAT) of male mice, whereas it increased expression of uncoupling protein 1 and other brown adipocyte markers in the gWAT of female mice. Moreover, gWAT from female mice demonstrated higher levels of oxygen consumption and mitochondrial content compared to gWAT from male mice. FGF21 expression was increased in liver tissue by the MCD diet, and the degree of upregulation was significantly higher in the livers of female mice. The endocrine effect of FGF21 was responsible, in part, for the sex-specific browning of gonadal white adipose tissue. Collectively, these data demonstrated that distinctively female-specific browning of white adipose tissue aids in protecting female mice against MCD diet-induced fatty liver disease.

Sex-specific metabolic interactions between liver and adipose tissue in MCD diet-induced non-alcoholic fatty liver disease

PubMed Central

Lee, Yun-Hee; Kim, Sou Hyun; Kim, Sang-Nam; Kwon, Hyun-Jung; Kim, Jeong-Dong; Oh, Ji Youn; Jung, Young-Suk

2016-01-01

Higher susceptibility to metabolic disease in male exemplifies the importance of sexual dimorphism in pathogenesis. We hypothesized that the higher incidence of non-alcoholic fatty liver disease in males involves sex-specific metabolic interactions between liver and adipose tissue. In the present study, we used a methionine-choline deficient (MCD) diet-induced fatty liver mouse model to investigate sex differences in the metabolic response of the liver and adipose tissue. After 2 weeks on an MCD-diet, fatty liver was induced in a sex-specific manner, affecting male mice more severely than females. The MCD-diet increased lipolytic enzymes in the gonadal white adipose tissue (gWAT) of male mice, whereas it increased expression of uncoupling protein 1 and other brown adipocyte markers in the gWAT of female mice. Moreover, gWAT from female mice demonstrated higher levels of oxygen consumption and mitochondrial content compared to gWAT from male mice. FGF21 expression was increased in liver tissue by the MCD diet, and the degree of upregulation was significantly higher in the livers of female mice. The endocrine effect of FGF21 was responsible, in part, for the sex-specific browning of gonadal white adipose tissue. Collectively, these data demonstrated that distinctively female-specific browning of white adipose tissue aids in protecting female mice against MCD diet-induced fatty liver disease. PMID:27409675

New Insights into the Pathogenesis of Alcohol-Induced ER Stress and Liver Diseases.

PubMed

Ji, Cheng

2014-01-01

Alcohol-induced liver disease increasingly contributes to human mortality worldwide. Alcohol-induced endoplasmic reticulum (ER) stress and disruption of cellular protein homeostasis have recently been established as a significant mechanism contributing to liver diseases. The alcohol-induced ER stress occurs not only in cultured hepatocytes but also  in vivo  in the livers of several species including mouse, rat, minipigs, zebrafish, and humans. Identified causes for the ER stress include acetaldehyde, oxidative stress, impaired one carbon metabolism, toxic lipid species, insulin resistance, disrupted calcium homeostasis, and aberrant epigenetic modifications. Importance of each of the causes in alcohol-induced liver injury depends on doses, duration and patterns of alcohol exposure, genetic disposition, environmental factors, cross-talks with other pathogenic pathways, and stages of liver disease. The ER stress may occur more or less all the time during alcohol consumption, which interferes with hepatic protein homeostasis, proliferation, and cell cycle progression promoting development of advanced liver diseases. Emerging evidence indicates that long-term alcohol consumption and ER stress may directly be involved in hepatocellular carcinogenesis (HCC). Dissecting ER stress signaling pathways leading to tumorigenesis will uncover potential therapeutic targets for intervention and treatment of human alcoholics with liver cancer.

Oral administration of pentachlorophenol induces interferon signaling mRNAs in C57BL/6 male mouse liver.

PubMed

Kanno, Jun; Aisaki, Ken-ichi; Igarashi, Katsuhide; Kitajima, Satoshi; Matsuda, Nae; Morita, Koichi; Tsuji, Masaki; Moriyama, Noriko; Furukawa, Yusuke; Otsuka, Maki; Tachihara, Erika; Nakatsu, Noriyuki; Kodama, Yukio

2013-01-01

Pentachlorophenol (PCP) was monitored for transcriptome responses in adult mouse liver at 2, 4, 8 and 24 hr after a single oral administration at four dose levels, 0, 10, 30 and 100 mg/kg. The expression data obtained using Affymetrix GeneChip MOE430 2.0 were absolutized by the Percellome method and expressed as three dimensional (3D) surface graphs with axes of time, dose and copy numbers of mRNA per cell. We developed the programs RSort, for comprehensive screening of the 3D surface data and PercellomeExploror for cross-referencing and confirmed the significant responses by visual inspection. In the first 8 hr, approximately 100 probe sets (PSs) related to PXR/SXR and Cyp2a4 and other metabolic enzymes were induced whereas Fos and JunB were suppressed. At 24 hr, about 1,200 PSs were strongly induced. We cross-referenced the Percellome database consisting of 111 chemicals on the liver transcriptome and found that about half of the PSs belonged to the metabolic pathways including Nrf2-mediated oxidative stress response networks shared with some of the 111 chemicals. The other half of the induced genes were interferon signaling network genes (ISG) and their induction was unique to PCP. Toll like receptors and other pattern recognition receptors, interferon regulatory factors and interferon alpha itself were included but inflammatory cytokines were not induced. In summary, these data indicated that functional symptoms of PCP treatment, such as hyperthermia and profuse sweating might be mediated by the ISG rather than the previously documented mitochondrial uncoupling mechanism. PCP might become a hint for developing low molecular weight orally available interferon mimetic drugs following imiquimod and RO4948191 as agonists of toll-like receptor and interferon receptor.

Overexpression of the cholesterol-binding protein MLN64 induces liver damage in the mouse

PubMed Central

Tichauer, Juan Enrique; Morales, María Gabriela; Amigo, Ludwig; Galdames, Leopoldo; Klein, Andrés; Quiñones, Verónica; Ferrada, Carla; R, Alejandra Alvarez; Rio, Marie-Christine; Miquel, Juan Francisco; Rigotti, Attilio; Zanlungo, Silvana

2007-01-01

AIM: To examine the in vivo phenotype associated with hepatic metastatic lymph node 64 (MLN64) over-expression. METHODS: Recombinant-adenovirus-mediated MLN64 gene transfer was used to overexpress MLN64 in the livers of C57BL/6 mice. We measured the effects of MLN64 overexpression on hepatic cholesterol content, bile flow, biliary lipid secretion and apoptosis markers. For in vitro studies cultured CHO cells with transient MLN64 overexpression were utilized and apoptosis by TUNEL assay was measured. RESULTS: Livers from Ad.MLN64-infected mice exhibited early onset of liver damage and apoptosis. This response correlated with increases in liver cholesterol content and biliary bile acid concentration, and impaired bile flow. We investigated whether liver MLN64 expression could be modulated in a murine model of hepatic injury. We found increased hepatic MLN64 mRNA and protein levels in mice with chenodeoxycholic acid-induced liver damage. In addition, cultured CHO cells with transient MLN64 overexpression showed increased apoptosis. CONCLUSION: In summary, hepatic MLN64 over-expression induced damage and apoptosis in murine livers and altered cholesterol metabolism. Further studies are required to elucidate the relevance of these findings under physiologic and disease conditions. PMID:17589922

CRISPR/Cas9 Engineering of Adult Mouse Liver Demonstrates That the Dnajb1-Prkaca Gene Fusion Is Sufficient to Induce Tumors Resembling Fibrolamellar Hepatocellular Carcinoma.

PubMed

Engelholm, Lars H; Riaz, Anjum; Serra, Denise; Dagnæs-Hansen, Frederik; Johansen, Jens V; Santoni-Rugiu, Eric; Hansen, Steen H; Niola, Francesco; Frödin, Morten

2017-12-01

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a primary liver cancer that predominantly affects children and young adults with no underlying liver disease. A somatic, 400 Kb deletion on chromosome 19 that fuses part of the DnaJ heat shock protein family (Hsp40) member B1 gene (DNAJB1) to the protein kinase cAMP-activated catalytic subunit alpha gene (PRKACA) has been repeatedly identified in patients with FL-HCC. However, the DNAJB1-PRKACA gene fusion has not been shown to induce liver tumorigenesis. We used the CRISPR/Cas9 technique to delete in mice the syntenic region on chromosome 8 to create a Dnajb1-Prkaca fusion and monitored the mice for liver tumor development. We delivered CRISPR/Cas9 vectors designed to juxtapose exon 1 of Dnajb1 with exon 2 of Prkaca to create the Dnajb1-Prkaca gene fusion associated with FL-HCC, or control Cas9 vector, via hydrodynamic tail vein injection to livers of 8-week-old female FVB/N mice. These mice did not have any other engineered genetic alterations and were not exposed to liver toxins or carcinogens. Liver tissues were collected 14 months after delivery; genomic DNA was analyzed by PCR to detect the Dnajb1-Prkaca fusion, and tissues were characterized by histology, immunohistochemistry, RNA sequencing, and whole-exome sequencing. Livers from 12 of the 15 mice given the vectors to induce the Dnajb1-Prkaca gene fusion, but none of the 11 mice given the control vector, developed neoplasms. The tumors contained the Dnajb1-Prkaca gene fusion and had histologic and cytologic features of human FL-HCCs: large polygonal cells with granular, eosinophilic, and mitochondria-rich cytoplasm, prominent nucleoli, and markers of hepatocytes and cholangiocytes. In comparing expression levels of genes between the mouse tumor and non-tumor liver cells, we identified changes similar to those detected in human FL-HCC, which included genes that affect cell cycle and mitosis regulation. Genomic analysis of mouse neoplasms induced by

Obstructive Sleep Apnea and Non-Alcoholic Fatty Liver Disease: Is the Liver Another Target?

PubMed Central

Mirrakhimov, Aibek E.; Polotsky, Vsevolod Y.

2012-01-01

Obstructive sleep apnea (OSA) is recurrent obstruction of the upper airway during sleep leading to intermittent hypoxia (IH). OSA has been associated with all components of the metabolic syndrome as well as with non-alcoholic fatty liver disease (NAFLD). NAFLD is a common condition ranging in severity from uncomplicated hepatic steatosis to steatohepatitis (NASH), liver fibrosis, and cirrhosis. The gold standard for the diagnosis and staging of NAFLD is liver biopsy. Obesity and insulin resistance lead to liver steatosis, but the causes of the progression to NASH are not known. Emerging evidence suggests that OSA may play a role in the progression of hepatic steatosis and the development of NASH. Several cross-sectional studies showed that the severity of IH in patients with OSA predicted the severity of NAFLD on liver biopsy. However, neither prospective nor interventional studies with continuous positive airway pressure treatment have been performed. Studies in a mouse model showed that IH causes triglyceride accumulation in the liver and liver injury as well as hepatic inflammation. The mouse model provided insight in the pathogenesis of liver injury showing that (1) IH accelerates the progression of hepatic steatosis by inducing adipose tissue lipolysis and increasing free fatty acids (FFA) flux into the liver; (2) IH up-regulates lipid biosynthetic pathways in the liver; (3) IH induces oxidative stress in the liver; (4) IH up-regulates hypoxia inducible factor 1 alpha and possibly HIF-2 alpha, which may increase hepatic steatosis and induce liver inflammation and fibrosis. However, the role of FFA and different transcription factors in the pathogenesis of IH-induced NAFLD is yet to be established. Thus, multiple lines of evidence suggest that IH of OSA may contribute to the progression of NAFLD but definitive clinical studies and experiments in the mouse model have yet to be done. PMID:23087670

Chronic intermittent hypoxia causes hepatitis in a mouse model of diet-induced fatty liver.

PubMed

Savransky, Vladimir; Bevans, Shannon; Nanayakkara, Ashika; Li, Jianguo; Smith, Philip L; Torbenson, Michael S; Polotsky, Vsevolod Y

2007-10-01

Obstructive sleep apnea (OSA) causes chronic intermittent hypoxia (CIH) during sleep. OSA is associated with nonalcoholic steatohepatitis (NASH) in obese individuals and may contribute to progression of nonalcoholic fatty liver disease from steatosis to NASH. The purpose of this study was to examine whether CIH induces inflammatory changes in the liver in mice with diet-induced hepatic steatosis. C57BL/6J mice (n = 8) on a high-fat, high-cholesterol diet were exposed to CIH for 6 mo and were compared with mice on the same diet exposed to intermittent air (control; n = 8). CIH caused liver injury with an increase in serum ALT (461 +/- 58 U/l vs. 103 +/- 16 U/l in the control group; P < 0.01) and AST (637 +/- 37 U/l vs. 175 +/- 13 U/l in the control group; P < 0.001), whereas alkaline phosphatase and total bilirubin levels were unchanged. Histology revealed hepatic steatosis in both groups, with mild accentuation of fat staining in the zone 3 hepatocytes in mice exposed to CIH. Animals exposed to CIH exhibited lobular inflammation and fibrosis in the liver, which were not evident in control mice. CIH caused significant increases in lipid peroxidation in serum and liver tissue; significant increases in hepatic levels of myeloperoxidase and proinflammatory cytokines IL-1beta, IL-6, and CXC chemokine MIP-2; a trend toward an increase in TNF-alpha; and an increase in alpha1(I)-collagen mRNA. We conclude that CIH induces lipid peroxidation and inflammation in the livers of mice on a high-fat, high-cholesterol diet.

A New Mouse Model That Spontaneously Develops Chronic Liver Inflammation and Fibrosis

PubMed Central

Fransén-Pettersson, Nina; Duarte, Nadia; Nilsson, Julia; Lundholm, Marie; Mayans, Sofia; Larefalk, Åsa; Hannibal, Tine D.; Hansen, Lisbeth; Schmidt-Christensen, Anja; Ivars, Fredrik; Cardell, Susanna; Palmqvist, Richard; Rozell, Björn

2016-01-01

Here we characterize a new animal model that spontaneously develops chronic inflammation and fibrosis in multiple organs, the non-obese diabetic inflammation and fibrosis (N-IF) mouse. In the liver, the N-IF mouse displays inflammation and fibrosis particularly evident around portal tracts and central veins and accompanied with evidence of abnormal intrahepatic bile ducts. The extensive cellular infiltration consists mainly of macrophages, granulocytes, particularly eosinophils, and mast cells. This inflammatory syndrome is mediated by a transgenic population of natural killer T cells (NKT) induced in an immunodeficient NOD genetic background. The disease is transferrable to immunodeficient recipients, while polyclonal T cells from unaffected syngeneic donors can inhibit the disease phenotype. Because of the fibrotic component, early on-set, spontaneous nature and reproducibility, this novel mouse model provides a unique tool to gain further insight into the underlying mechanisms mediating transformation of chronic inflammation into fibrosis and to evaluate intervention protocols for treating conditions of fibrotic disorders. PMID:27441847

Protective effect of oligomeric proanthocyanidins against alcohol-induced liver steatosis and injury in mice.

PubMed

Wang, Zhiguo; Su, Bo; Fan, Sumei; Fei, Haixia; Zhao, Wei

2015-03-20

The long-term consumption of alcohol has been associated with multiple pathologies at all levels, such as alcoholism, chronic pancreatitis, malnutrition, alcoholic liver disease (ALD) and cancer. In the current study, we investigated the protective effect of oligomeric proanthocyanidins (OPC) against alcohol-induced liver steatosis and injury and the possible mechanisms using ethanol-induced chronic liver damage mouse models. The results showed that OPC significantly improved alcohol-induced dyslipidemia and alleviated liver steatosis by reducing levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total triglyceride (TG), total cholesterol (TC), low-density cholesterol (LDL-c) and liver malondialdehyde (MDA), and increasing levels of serum high-density lipoprotein (HDL-c), liver superoxide dismutase (SOD). Further investigation indicated that OPC markedly decreased the expressions of lipid synthesis genes and inflammation genes such as sterol regulatory element-binding protein-1c (Srebp-1c), protein-2 (Srebp2), interleukin IL-1β, IL-6 and TNF-α. Furthermore, AML-12 cells line was used to investigate the possible mechanisms which indicated that OPC might alleviate liver steatosis and damage through AMP-activated protein kinase (AMPK) activation involving oxidative stress. In conclusion, our study demonstrated excellent protective effect of OPC against alcohol-induced liver steatosis and injury, which could a potential drug for the treatment of alcohol-induced liver injury in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

The critical role played by endotoxin-induced liver autophagy in the maintenance of lipid metabolism during sepsis.

PubMed

Chung, Ki Wung; Kim, Kyung Mok; Choi, Yeon Ja; An, Hye Jin; Lee, Bonggi; Kim, Dae Hyun; Lee, Eun Kyeong; Im, Eunok; Lee, Jaewon; Im, Dong Soon; Yu, Byung Pal; Chung, Hae Young

2017-07-03

Macroautophagy/autophagy is a central mechanism by which cells maintain integrity and homeostasis, and endotoxin-induced autophagy plays important roles in innate immunity. Although TLR4 stimulation mediated by lipopolysaccharide (LPS) also upregulates autophagy in hepatocytes and liver, its physiological role remains elusive. The objective of this study was to determine the role of LPS-induced autophagy in the regulation of liver lipid metabolism. LPS treatment (5 mg/kg) increased autophagy, as detected by LC3 conversion and transmission electron microscopy (TEM) analysis in C57BL6 mouse livers. AC2F hepatocytes also showed increased autophagic flux after LPS treatment (1 μg/ml). To investigate the role of LPS-induced autophagy further, liver lipid metabolism changes in LPS-treated mice and fasted controls were compared. Interestingly, LPS-treated mice showed less lipid accumulation in liver than fasted mice despite increased fatty acid uptake and lipid synthesis-associated genes. In vitro analysis using AC2F hepatocytes demonstrated LPS-induced autophagy influenced the degradation of lipid droplets. Inhibition of LPS-induced autophagy using bafilomycin A 1 or Atg7 knockdown significantly increased lipid accumulation in AC2F hepatocytes. In addition, pretreatment with chloroquine aggravated LPS-induced lipid accumulation and inflammation in C57BL6 mouse livers. The physiological importance of autophagy was verified in LPS-treated young and aged rats. Autophagic response was diminished in LPS-treated aged rats and lipid metabolism was impaired during sepsis, indicating autophagy response is important for regulating lipid metabolism after endotoxin challenge. Our findings demonstrate endotoxin-induced autophagy is important for the regulation of lipid metabolism, and suggest that autophagy helps maintain lipid metabolism homeostasis during sepsis.

Role of activin A in carbon tetrachloride-induced acute liver injury.

PubMed

Wang, Dong-Hui; Wang, Yi-Nan; Ge, Jing-Yan; Liu, Hai-Yan; Zhang, Hong-Jun; Qi, Yan; Liu, Zhong-Hui; Cui, Xue-Ling

2013-06-28

To investigate the expression and role of activin A in a mouse model of acute chemical liver injury. Acute liver injury in C57BL/6 male mice was induced by intraperitoneal injection with carbon tetrachloride (CCl4) (0.5 mL/kg, body weight) dissolved in olive oil (1:19 v/v). Mice were sacrificed 1, 3, 5 and 7 d after the treatment. The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum were examined and pathological changes of liver observed by hematoxylin and eosin staining to evaluate the liver injury. Activin A protein levels in serum and hepatic tissue homogenate of mice were detected by enzyme-linked immunosorbent assay, and the expression pattern of activin A protein in livers of mice was examined by immunohistochemistry. Activin type IIA receptor (ActRIIA) and Smad3 expressions in the liver were analyzed by real-time quantitative reverse transcription-polymerase chain reaction. In order to further investigate the role of activin A, we also utilized activin A blocking experiment by anti-activin A antibody (500 μg/kg, body weight) injection into mouse tail vein. In CCl4-treated mice, serum ALT and AST levels were significantly increased, compared with that in control mice (P < 0.01). Furthermore, the serious necrosis was observed around hepatic portal areas in CCl4-treated mice. Simultaneously, activin A levels in serum and hepatic tissue homogenate of mice treated with CCl4 for 1, 3 and 5 d increased significantly, compared with that in control mice (P < 0.01). Activin A protein expression in hepatocytes not within the necrotic area was also upregulated in mice following CCl4 treatment. Not only activin A, but also ActRIIA and activin signaling molecule Smad3 mRNA expressions in injury liver induced by CCl4 were significantly higher than that in control liver. In addition, levels of serum ALT and AST in CCl4-treated mice were significantly decreased by injection of anti-activin A antibody to block endogenous activin A

Parkin regulates mitophagy and mitochondrial function to protect against alcohol-induced liver injury and steatosis in mice

PubMed Central

Williams, Jessica A.; Ni, Hong-Min; Ding, Yifeng

2015-01-01

Alcoholic liver disease claims two million lives per year. We previously reported that autophagy protected against alcohol-induced liver injury and steatosis by removing damaged mitochondria. However, the mechanisms for removal of these mitochondria are unknown. Parkin is an evolutionarily conserved E3 ligase that is recruited to damaged mitochondria to initiate ubiquitination of mitochondrial outer membrane proteins and subsequent mitochondrial degradation by mitophagy. In addition to its role in mitophagy, Parkin has been shown to have other roles in maintaining mitochondrial function. We investigated whether Parkin protected against alcohol-induced liver injury and steatosis using wild-type (WT) and Parkin knockout (KO) mice treated with alcohol by the acute-binge and Gao-binge (chronic plus acute-binge) models. We found that Parkin protected against liver injury in both alcohol models, likely because of Parkin's role in maintaining a population of healthy mitochondria. Alcohol caused greater mitochondrial damage and oxidative stress in Parkin KO livers compared with WT livers. After alcohol treatment, Parkin KO mice had severely swollen and damaged mitochondria that lacked cristae, which were not seen in WT mice. Furthermore, Parkin KO mice had decreased mitophagy, β-oxidation, mitochondrial respiration, and cytochrome c oxidase activity after acute alcohol treatment compared with WT mice. Interestingly, liver mitochondria seemed able to adapt to alcohol treatment, but Parkin KO mouse liver mitochondria had less capacity to adapt to Gao-binge treatment compared with WT mouse liver mitochondria. Overall, our findings indicate that Parkin is an important mediator of protection against alcohol-induced mitochondrial damage, steatosis, and liver injury. PMID:26159696

Oxidative phosphorylation flexibility in the liver of mice resistant to high-fat diet-induced hepatic steatosis.

PubMed

Poussin, Carinne; Ibberson, Mark; Hall, Diana; Ding, Jun; Soto, Jamie; Abel, E Dale; Thorens, Bernard

2011-09-01

To identify metabolic pathways that may underlie susceptibility or resistance to high-fat diet-induced hepatic steatosis. We performed comparative transcriptomic analysis of the livers of A/J and C57Bl/6 mice, which are, respectively, resistant and susceptible to high-fat diet-induced hepatosteatosis and obesity. Mice from both strains were fed a normal chow or a high-fat diet for 2, 10, and 30 days, and transcriptomic data were analyzed by time-dependent gene set enrichment analysis. Biochemical analysis of mitochondrial respiration was performed to confirm the transcriptomic analysis. Time-dependent gene set enrichment analysis revealed a rapid, transient, and coordinate upregulation of 13 oxidative phosphorylation genes after initiation of high-fat diet feeding in the A/J, but not in the C57Bl/6, mouse livers. Biochemical analysis using liver mitochondria from both strains of mice confirmed a rapid increase by high-fat diet feeding of the respiration rate in A/J but not C57Bl/6 mice. Importantly, ATP production was the same in both types of mitochondria, indicating increased uncoupling of the A/J mitochondria. Together with previous data showing increased expression of mitochondrial β-oxidation genes in C57Bl/6 but not A/J mouse livers, our present study suggests that an important aspect of the adaptation of livers to high-fat diet feeding is to increase the activity of the oxidative phosphorylation chain and its uncoupling to dissipate the excess of incoming metabolic energy and to reduce the production of reactive oxygen species. The flexibility in oxidative phosphorylation activity may thus participate in the protection of A/J mouse livers against the initial damages induced by high-fat diet feeding that may lead to hepatosteatosis.

Spatio-temporal Model of Xenobiotic Distribution and Metabolism in an in Silico Mouse Liver Lobule

NASA Astrophysics Data System (ADS)

Fu, Xiao; Sluka, James; Clendenon, Sherry; Glazier, James; Ryan, Jennifer; Dunn, Kenneth; Wang, Zemin; Klaunig, James

Our study aims to construct a structurally plausible in silico model of a mouse liver lobule to simulate the transport of xenobiotics and the production of their metabolites. We use a physiologically-based model to calculate blood-flow rates in a network of mouse liver sinusoids and simulate transport, uptake and biotransformation of xenobiotics within the in silico lobule. Using our base model, we then explore the effects of variations of compound-specific (diffusion, transport and metabolism) and compound-independent (temporal alteration of blood flow pattern) parameters, and examine their influence on the distribution of xenobiotics and metabolites. Our simulations show that the transport mechanism (diffusive and transporter-mediated) of xenobiotics and blood flow both impact the regional distribution of xenobiotics in a mouse hepatic lobule. Furthermore, differential expression of metabolic enzymes along each sinusoid's portal to central axis, together with differential cellular availability of xenobiotics, induce non-uniform production of metabolites. Thus, the heterogeneity of the biochemical and biophysical properties of xenobiotics, along with the complexity of blood flow, result in different exposures to xenobiotics for hepatocytes at different lobular locations. We acknowledge support from National Institute of Health GM 077138 and GM 111243.

Quantitative changes in endogenous DNA adducts correlate with conazole mutagenicity and tumorigenicity in mouse liver.**

EPA Science Inventory

We have previously shown that the conazole fungicides triadimefon and propiconazole, which are tumorigenic in mouse liver, are in vivo mouse liver mutagens in the Big Blue" transgenic mutation assay when administered in feed at tumorigenic doses. The nontumorigenic conazole myclo...

Quantitative changes in endogenous DNA adducts correlate with conazole mutagenicity and tumorigenicity in mouse liver.

EPA Science Inventory

We have previously shown that the conazole fungicides triadimefon and propiconazole, which are tumorigenic in mouse liver, are in vivo mouse liver mutagens in the Big Blue" transgenic mutation assay when administered in feed at tumorigenic doses. The nontumorigenic conazole myclo...

Identification of an epigenetic signature of early mouse liver regeneration that is disrupted by Zn-HDAC inhibition.

PubMed

Huang, Jiansheng; Schriefer, Andrew E; Yang, Wei; Cliften, Paul F; Rudnick, David A

2014-11-01

Liver regeneration has been well studied with hope of discovering strategies to improve liver disease outcomes. Nevertheless, the signals that initiate such regeneration remain incompletely defined, and translation of mechanism-based pro-regenerative interventions into new treatments for hepatic diseases has not yet been achieved. We previously reported the isoform-specific regulation and essential function of zinc-dependent histone deacetylases (Zn-HDACs) during mouse liver regeneration. Those data suggest that epigenetically regulated anti-proliferative genes are deacetylated and transcriptionally suppressed by Zn-HDAC activity or that pro-regenerative factors are acetylated and induced by such activity in response to partial hepatectomy (PH). To investigate these possibilities, we conducted genome-wide interrogation of the liver histone acetylome during early PH-induced liver regeneration in mice using acetyL-histone chromatin immunoprecipitation and next generation DNA sequencing. We also compared the findings of that study to those seen during the impaired regenerative response that occurs with Zn-HDAC inhibition. The results reveal an epigenetic signature of early liver regeneration that includes both hyperacetylation of pro-regenerative factors and deacetylation of anti-proliferative and pro-apoptotic genes. Our data also show that administration of an anti-regenerative regimen of the Zn-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) not only disrupts gene-specific pro-regenerative changes in liver histone deacetylation but also reverses PH-induced effects on histone hyperacetylation. Taken together, these studies offer new insight into and suggest novel hypotheses about the epigenetic mechanisms that regulate liver regeneration.

Identification of an epigenetic signature of early mouse liver regeneration that is disrupted by Zn-HDAC inhibition

PubMed Central

Huang, Jiansheng; Schriefer, Andrew E; Yang, Wei; Cliften, Paul F; Rudnick, David A

2014-01-01

Liver regeneration has been well studied with hope of discovering strategies to improve liver disease outcomes. Nevertheless, the signals that initiate such regeneration remain incompletely defined, and translation of mechanism-based pro-regenerative interventions into new treatments for hepatic diseases has not yet been achieved. We previously reported the isoform-specific regulation and essential function of zinc-dependent histone deacetylases (Zn-HDACs) during mouse liver regeneration. Those data suggest that epigenetically regulated anti-proliferative genes are deacetylated and transcriptionally suppressed by Zn-HDAC activity or that pro-regenerative factors are acetylated and induced by such activity in response to partial hepatectomy (PH). To investigate these possibilities, we conducted genome-wide interrogation of the liver histone acetylome during early PH-induced liver regeneration in mice using acetyL-histone chromatin immunoprecipitation and next generation DNA sequencing. We also compared the findings of that study to those seen during the impaired regenerative response that occurs with Zn-HDAC inhibition. The results reveal an epigenetic signature of early liver regeneration that includes both hyperacetylation of pro-regenerative factors and deacetylation of anti-proliferative and pro-apoptotic genes. Our data also show that administration of an anti-regenerative regimen of the Zn-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) not only disrupts gene-specific pro-regenerative changes in liver histone deacetylation but also reverses PH-induced effects on histone hyperacetylation. Taken together, these studies offer new insight into and suggest novel hypotheses about the epigenetic mechanisms that regulate liver regeneration. PMID:25482284

Parkin regulates mitophagy and mitochondrial function to protect against alcohol-induced liver injury and steatosis in mice.

PubMed

Williams, Jessica A; Ni, Hong-Min; Ding, Yifeng; Ding, Wen-Xing

2015-09-01

Alcoholic liver disease claims two million lives per year. We previously reported that autophagy protected against alcohol-induced liver injury and steatosis by removing damaged mitochondria. However, the mechanisms for removal of these mitochondria are unknown. Parkin is an evolutionarily conserved E3 ligase that is recruited to damaged mitochondria to initiate ubiquitination of mitochondrial outer membrane proteins and subsequent mitochondrial degradation by mitophagy. In addition to its role in mitophagy, Parkin has been shown to have other roles in maintaining mitochondrial function. We investigated whether Parkin protected against alcohol-induced liver injury and steatosis using wild-type (WT) and Parkin knockout (KO) mice treated with alcohol by the acute-binge and Gao-binge (chronic plus acute-binge) models. We found that Parkin protected against liver injury in both alcohol models, likely because of Parkin's role in maintaining a population of healthy mitochondria. Alcohol caused greater mitochondrial damage and oxidative stress in Parkin KO livers compared with WT livers. After alcohol treatment, Parkin KO mice had severely swollen and damaged mitochondria that lacked cristae, which were not seen in WT mice. Furthermore, Parkin KO mice had decreased mitophagy, β-oxidation, mitochondrial respiration, and cytochrome c oxidase activity after acute alcohol treatment compared with WT mice. Interestingly, liver mitochondria seemed able to adapt to alcohol treatment, but Parkin KO mouse liver mitochondria had less capacity to adapt to Gao-binge treatment compared with WT mouse liver mitochondria. Overall, our findings indicate that Parkin is an important mediator of protection against alcohol-induced mitochondrial damage, steatosis, and liver injury. Copyright © 2015 the American Physiological Society.

Liver Zonation Index of Drug Transporter and Metabolizing Enzyme Protein Expressions in Mouse Liver Acinus.

PubMed

Tachikawa, Masanori; Sumiyoshiya, Yuna; Saigusa, Daisuke; Sasaki, Kazunari; Watanabe, Michitoshi; Uchida, Yasuo; Terasaki, Tetsuya

2018-05-01

The purpose of the present study was to clarify the molecular basis of zonated drug distributions in mouse liver based on the protein expression levels of transporters and metabolizing enzymes in periportal (PP) and pericentral (PC) vein regions of mouse hepatic lobules. The distributions of sulforhodamine 101 (SR-101), a substrate of organic anion transporting polypeptides (Oatps), and ribavirin, a substrate of equilibrative nucleoside transporter 1 (Ent1), were elucidated in frozen liver sections of mice, to which each compound had been intravenously administered. Regions strongly positive for SR-101 (SR-101 + ) and regions weakly positive or negative for SR-101 (SR-101 - ) were separated by laser microdissection. The zonated distribution of protein expression was quantified in terms of the liver zonation index. Quantitative targeted absolute proteomics revealed the selective expression of glutamine synthetase in the SR-101 + region, indicating predominant distribution of SR-101 in hepatocytes of the PC vein region. The protein levels of Oatp1a1, Oatp1b2, organic cation transporter 1 (Oct1), and cytochrome P450 (P450) 2e1 were greater in the PC vein regions, whereas the level of organic anion transporter 2 (Oat2) was greater in the PP vein regions. Mouse Oatp1a1 mediated SR-101 transport. On the other hand, there were no statistically significant differences in expression of Ent1, Na + -taurocholate cotransporting polypeptide, several canalicular transporters, P450 enzymes, and UDP-glucuronosyltransferases between the PP and PC vein regions. This is consistent with the almost uniform distribution of ribavirin in the liver. In conclusion, sinusoidal membrane transporters such as Oatp1a1, Oatp1b2, Oct1, and Oat2 appear to be determinants of the zonated distribution of drugs in the liver. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Lead suppresses chimeric human transferrin gene expression in transgenic mouse liver.

PubMed

Adrian, G S; Rivera, E V; Adrian, E K; Lu, Y; Buchanan, J; Herbert, D C; Weaker, F J; Walter, C A; Bowman, B H

1993-01-01

The major iron-transport protein in serum is transferrin (TF) which also has the capacity to transport other metals. This report presents evidence that synthesis of human TF can be regulated by the metal lead. Transgenic mice carrying chimeric human TF-chloramphenicol acetyl transferase (CAT) genes received lead or sodium salts by intraperitoneal injections or in drinking water. Transgene expression in liver was suppressed 31 to 50% by the lead treatment. Lead regulates human TF transgenes at the mRNA level since liver CAT enzyme activity, CAT protein, and TF-CAT mRNA levels were all suppressed. The dosages of lead did not alter synthesis of the other liver proteins, mouse TF and albumin, as measured by Northern blot analysis of total liver RNA and rocket immunoelectrophoresis of mouse sera. Moderate levels of lead exposure were sufficient to evoke the human TF transgene response; blood lead levels in mice that received lead acetate in drinking water ranged from 30 micrograms/dl to 56 micrograms/dl. In addition to suppressing expression of TF-CAT genes in transgenic mice, lead also suppressed synthesis of TF protein in cultured human hepatoma HepG2 cells. The regulation of human TF apparently differs from the regulation of mouse TF which is unresponsive to lead exposure.

Induction, immunochemical identity and immunofluorescence localization of an 80 000-molecular-weight peroxisome-proliferation-associated polypeptide (polypeptide PPA-80) and peroxisomal enoyl-CoA hydratase of mouse liver and renal cortex.

PubMed

Lalwani, N D; Reddy, M K; Mangkornkanok-Mark, M; Reddy, J K

1981-07-15

The hypolipidaemic drugs methyl clofenapate, BR-931, Wy-14643 and procetofen induced a marked proliferation of peroxisomes in the parenchymal cells of liver and the proximal-convoluted-tubular epithelium of mouse kidney. The proliferation of peroxisomes was associated with 6-12-fold increase in the peroxisomal palmitoyl-CoA oxidizing capacity of the mouse liver. Enhanced activity of the peroxisomal palmitoyl-CoA oxidation system was also found in the renal-cortical homogenates of hypolipidaemic-drug-treated mice. The activity of enoyl-CoA hydratase in the mouse liver increased 30-50-fold and in the kidney cortex 3-5-fold with hypolipidaemic-drug-induced peroxisome proliferation in these tissues, and over 95% of this induced activity was found to be heat-labile peroxisomal enzyme in both organs. Sodium dodecyl sulphate/polyacrylamide-gel-electrophoretic analysis of large-particle and microsomal fractions obtained from the liver and kidney cortex of mice treated with hypolipidaemic peroxisome proliferators demonstrated a substantial increase in the quantity of an 80000-mol.wt. peroxisome-proliferation-associated polypeptide (polypeptide PPA-80). The heat-labile peroxisomal enoyl-CoA hydratase was purified from the livers of mice treated with the hypolipidaemic drug methyl clofenapate; the antibodies raised against this electrophoretically homogeneous protein yielded a single immunoprecipitin band with purified mouse liver enoyl-CoA hydratase and with liver and kidney cortical extracts of normal and hypolipidaemic-drug-treated mice. These anti-(mouse liver enoyl-CoA hydratase) antibodies also cross-reacted with purified rat liver enoyl-CoA hydratase and with the polypeptide PPA-80 obtained from rat and mouse liver. Immunofluorescence studies with anti-(polypeptide PPA-80) and anti-(peroxisomal enoyl-CoA hydratase) provided visual evidence for the localization and induction of polypeptide PPA-80 and peroxisomal enoyl-CoA hydratase in the liver and kidney respectively

Involvement of TGF-β1/Smad3 Signaling in Carbon Tetrachloride-Induced Acute Liver Injury in Mice

PubMed Central

Niu, Liman; Cui, Xueling; Qi, Yan; Xie, Dongxue; Wu, Qian; Chen, Xinxin; Ge, Jingyan; Liu, Zhonghui

2016-01-01

Transforming growth factor-beta1 (TGF-β1) is a major factor in pathogenesis of chronic hepatic injury. Carbon tetrachloride (CCl4) is a liver toxicant, and CCl4-induced liver injury in mouse is a classical animal model of chemical liver injury. However, it is still unclear whether TGF-β1 is involved in the process of CCl4-induced acute chemical liver injury. The present study aimed to evaluate the role of TGF-β1 and its signaling molecule Smad3 in the acute liver injury induce by CCl4. The results showed that CCl4 induced acute liver injury in mice effectively confirmed by H&E staining of liver tissues, and levels of not only liver injury markers serum ALT and AST, but also serum TGF-β1 were elevated significantly in CCl4-treated mice, compared with the control mice treated with olive oil. Our data further revealed that TGF-β1 levels in hepatic tissue homogenate increased significantly, and type II receptor of TGF-β (TβRII) and signaling molecules Smad2, 3, mRNA expressions and Smad3 and phospho-Smad3 protein levels also increased obviously in livers of CCl4-treated mice. To clarify the effect of the elevated TGF-β1/Smad3 signaling on CCl4-induced acute liver injury, Smad3 in mouse liver was overexpressed in vivo by tail vein injection of Smad3-expressing plasmids. Upon CCl4 treatment, Smad3-overexpressing mice showed more severe liver injury identified by H&E staining of liver tissues and higher serum ALT and AST levels. Simultaneously, we found that Smad3-overexpressing mice treated with CCl4 showed more macrophages and neutrophils infiltration in liver and inflammatory cytokines IL-1β and IL-6 levels increment in serum when compared with those in control mice treated with CCl4. Moreover, the results showed that the apoptosis of hepatocytes increased significantly, and apoptosis-associated proteins Bax, cytochrome C and the cleaved caspase 3 expressions were up-regulated in CCl4-treated Smad3-overexpressing mice as well. These results suggested that TGF

Physiological characterization of a mouse model of cachexia in colorectal liver metastases.

PubMed

Murphy, Kate T; Struk, Adam; Malcontenti-Wilson, Cathy; Christophi, Christopher; Lynch, Gordon S

2013-05-15

Loss of skeletal muscle mass and function (cachexia) is severe in patients with colorectal liver metastases because of the large increase in resting energy expenditure but remains understudied because of a lack of suitable preclinical models. Our aim was to characterize a novel preclinical model of cachexia in colorectal liver metastases. We tested the hypothesis that mice with colorectal liver metastases would exhibit cachexia, as evidenced by a reduction in liver-free body mass, muscle mass, and physiological impairment. Twelve-week-old male CBA mice received an intrasplenic injection of Ringer solution (sham) or murine colorectal cancer cells (MoCR) to induce colorectal liver metastases. At end-point (20-29 days), the livers of MoCR mice were infiltrated completely with metastases, and MoCR mice had reduced liver-free body mass, muscle mass, and epididymal fat mass compared with sham controls (P < 0.03). MoCR mice exhibited impaired rotarod performance and grip strength (P < 0.03). Histochemical analyses of tibialis anterior muscles from MoCR mice revealed muscle fiber atrophy and reduced oxidative enzyme activity (P < 0.001). Adipose tissue remodeling was evident in MoCR mice, with reduced adipocyte diameter and greater infiltration of nonadipocyte tissue (P < 0.05). These findings reveal the MoCR mouse model exhibits significant cachexia and is a suitable preclinical model of cachexia in colorectal liver metastases. This model should be used for identifying effective treatments for cachexia to improve quality of life and reduce mortality in patients with colorectal liver metastases.

Protective effects of silymarin against bisphenol A-induced hepatotoxicity in mouse liver

PubMed Central

Zaulet, Mihaela; Kevorkian, Steliana Elvira Maria; Dinescu, Sorina; Cotoraci, Coralia; Suciu, Maria; Herman, Hildegard; Buburuzan, Laura; Badulescu, Liliana; Ardelean, Aurel; Hermenean, Anca

2017-01-01

Bisphenol A (BPA) is an endocrine-disrupting chemical released into the environment, with severe consequences for human health, including metabolic syndrome and associated pathological conditions. Due to limited information on BPA-induced hepatotoxicity, the present study focused on investigating the association between BPA-induced toxicity and inflammatory markers in the liver, and how these injuries may be alleviated using the natural agent silymarin, a flavonoid with antioxidant properties obtained from Silybum marianum. Administration of BPA to male CD-1 mice for 10 days caused a significant increase in the number of cells immunopositive for interleukin 6 and tumor necrosis factor-α, pro-inflammatory cytokines that mediate the hepatic inflammatory response. Treatment with 200 mg/kg of silymarin concurrently with BPA for 10 days resulted in a diminished level of pro-inflammatory cytokines and in significantly reduced ultrastructural injuries. Additionally, silymarin was able to restore the significantly decreased glycogen deposits observed following BPA exposure to normal levels, thus favoring hepatic glycogenesis. This study represents the first report of silymarin ability to reduce hepatic lesions and to counteract inflammation caused by BPA in mice. A dose of 200 mg/kg silymarin was sufficient to induce a protective effect against structural and ultrastructural injuries induced by BPA and to lower the levels of pro-inflammatory cytokines observed in murine liver tissue following exposure to BPA. PMID:28450905

Branched-Chain Amino Acids Ameliorate Fibrosis and Suppress Tumor Growth in a Rat Model of Hepatocellular Carcinoma with Liver Cirrhosis

PubMed Central

Cha, Jung Hoon; Bae, Si Hyun; Kim, Hye Lim; Park, Na Ri; Choi, Eun Suk; Jung, Eun Sun; Choi, Jong Young; Yoon, Seung Kew

2013-01-01

Purpose Recent studies have revealed that branched-chain amino acids (BCAA) reduce the development of hepatocellular carcinoma (HCC) in patients with obesity and hepatitis C virus infection by improving insulin resistance (IR). The aim of this study was to examine the anti-cancer and anti-fibrotic effects of BCAA on the development of diethylnitrosamine (DEN)-induced HCC and liver cirrhosis in a rat model. Methods Male SD rats received weekly intraperitoneal injections of DEN (50 mg/kg of body weight) for 16 weeks to induce HCC. They were fed a diet containing 3% casein, 3% or 6% BCAA for 13 weeks beginning 6 weeks after DEN administration. DEN was used to induce HCC through stepwise development from cirrhosis to HCC. The effect of BCAA was evaluated in tumor tissues by histopathologic analyses, reverse transcription-polymerase chain reaction, and Western blotting. Results The mean area and number of dysplastic nodules (DNs) and tumors in the casein group tended to be larger than those in the BCAA group 16 weeks after DEN administration. The mean fibrotic area in the BCAA group was smaller than that in the casein group. The BCAA group showed decreased mRNA levels for markers of fibrosis, angiogenesis, and apoptosis inhibition. Compared with the casein group, the BCAA group had lower levels of α-smooth muscle actin, vascular endothelial growth factor, p-β-catenin, p-p38 mitogen-activated protein kinase, proliferating cell nuclear antigen, and caspase-3 protein expression, as well as a higher level of cleaved caspase-3 protein expression. Conclusions BCAA supplementation of the diet ameliorated liver fibrosis and HCC development in a DEN-induced rat model of HCC with liver cirrhosis, but not in the IR model. These results provide a rationale for anti-fibrosis and chemoprevention using BCAA treatment for HCC with liver cirrhosis, as well as decreasing the ammonia level. PMID:24223741

Protective Effect of Boiled and Freeze-dried Mature Silkworm Larval Powder Against Diethylnitrosamine-induced Hepatotoxicity in Mice.

PubMed

Cho, Jae-Min; Kim, Kee-Young; Ji, Sang-Deok; Kim, Eun-Hee

2016-09-01

Hepatocellular carcinoma (HCC) is a representative inflammation-associated cancer and known to be the most frequent tumors. HCC may also induce important pro- and anti-tumor immune reactions. However, the underlying mechanisms are unsatisfactorily identified. We investigated the protective effect of boiled and freeze-dried mature silkworm larval powder (BMSP) on diethylnitrosamine (DEN)-induced hepatotoxicity in mice. Mice were fed with diet containing BMSP (0.1, 1, and 10 g/kg) for two weeks and DEN (100 mg/kg, intraperitoneally) was injected 18 hours before the end of this experiment. Liver toxicity was determined in serum and histopathological examination was assessed in the liver tissues. Infiltration of immune cells and expressions of inflammatory cytokines and chemokines were also examined. Pretreatment with BMSP reduced necrotic and histopathological changes induced by DEN in the liver. Measurement of serum biochemical indicators, the levels of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase, showed that pretreatment with BMSP also decreased DEN-induced hepatotoxicity. In addition, BMSP inhibited the macrophage and CD31 infiltration in a dose-dependent manner. The expressions of interleukin-1β, IFN-γ and chemokines for T cell activation were decreased in BMSP pretreatment groups. BMSP may have a protective effect against acute liver injury by inhibiting necrosis and inflammatory response in DEN-treated mice.

Critical Role of PPAR-α in Perfluorooctanoic Acid– and Perfluorodecanoic Acid–Induced Downregulation of Oatp Uptake Transporters in Mouse Livers

PubMed Central

Cheng, Xingguo; Klaassen, Curtis D.

2008-01-01

Perfluorooctanoic acid (PFOA) and perfluorodecanoic acid (PFDA) have been detected globally in wildlife and humans. Data from a gene array indicate that PFOA decreases organic anion transporting polypeptides (Oatps) in liver. Na+-taurocholate cotransporting polypeptide (Ntcp) and Oatp1a1, 1a4, and 1b2 are major transporters responsible for uptake of bile acids (BAs) and other organic compounds into liver. The purpose of the present study was to determine the effects of two perfluorinated fatty acids, PFOA and PFDA, on mRNA and protein expression of hepatic uptake transporters Oatps and Ntcp, and to determine the underlying regulatory mechanisms by using peroxisome proliferator-activated receptor alpha (PPAR-α), constitutive androstane receptor, pregnane-X receptor, NF-E2–related factor 2, and farnesoid X receptor-null mouse models. After 2 days following a single i.p. administration, PFOA did not alter serum BA concentrations, but PFDA increased serum BA concentrations 300%. Furthermore, PFOA decreased mRNA and protein expression of Oatp1a1, 1a4, and 1b2, but not Ntcp in mouse liver. In contrast, PFDA decreased mRNA and protein expression of all four transporters, and decreased the mRNA expression in a dose-dependent manner, with the decrease of Oatp1a4 occurring at lower doses than the other three transporters. Multiple mechanisms are likely involved in the down-regulation of mouse Oatps and Ntcp by PFDA. By using the various transcription factor-null mice, PPAR-α was shown to play a central role in the down-regulation of Oatp1a1, 1a4, 1b2, and Ntcp by PFDA. The current studies provide important insight into understanding the mechanisms by which PFDA regulate the expression of hepatic uptake transporters. In conclusion, PFOA and PFDA decrease mouse liver uptake transporters primarily via activation of PPAR-α. PMID:18703564

Adult-Derived Human Liver Stem/Progenitor Cells Infused 3 Days Postsurgery Improve Liver Regeneration in a Mouse Model of Extended Hepatectomy

PubMed Central

Herrero, Astrid; Prigent, Julie; Lombard, Catherine; Rosseels, Valérie; Daujat-Chavanieu, Martine; Breckpot, Karine; Najimi, Mustapha; Deblandre, Gisèle; Sokal, Etienne M.

2017-01-01

There is growing evidence that cell therapy constitutes a promising strategy for liver regenerative medicine. In the setting of hepatic cancer treatments, cell therapy could prove a useful therapeutic approach for managing the acute liver failure that occurs following extended hepatectomy. In this study, we examined the influence of delivering adult-derived human liver stem/progenitor cells (ADHLSCs) at two different early time points in an immunodeficient mouse model (Rag2−/-IL2Rg-/-) that had undergone a 70% hepatectomy procedure. The hepatic mesenchymal cells were intrasplenically infused either immediately after surgery (n = 26) or following a critical 3-day period (n = 26). We evaluated the cells' capacity to engraft at day 1 and day 7 following transplantation by means of human Alu qPCR quantification, along with histological assessment of human albumin and α-smooth muscle actin. In addition, cell proliferation (anti-mouse and human Ki-67 staining) and murine liver weight were measured in order to evaluate liver regeneration. At day 1 posttransplantation, the ratio of human to mouse cells was similar in both groups, whereas 1 week posttransplantation this ratio was significantly improved (p < 0.016) in mice receiving ADHLSC injection at day 3 posthepatectomy (1.7%), compared to those injected at the time of surgery (1%). On the basis of liver weight, mouse liver regeneration was more extensive 1 week posttransplantation in mice transplanted with ADHLSCs (+65.3%) compared to that of mice from the sham vehicle group (+42.7%). In conclusion, infusing ADHLSCs 3 days after extensive hepatectomy improves the cell engraftment and murine hepatic tissue regeneration, thereby confirming that ADHLSCs could be a promising cell source for liver cell therapy and hepatic tissue repair. PMID:27657746

Different induction of LPA receptors by chemical liver carcinogens regulates cellular functions of liver epithelial WB-F344 cells.

PubMed

Hirane, Miku; Ishii, Shuhei; Tomimatsu, Ayaka; Fukushima, Kaori; Takahashi, Kaede; Fukushima, Nobuyuki; Honoki, Kanya; Tsujiuchi, Toshifumi

2016-11-01

Lysophosphatidic acid (LPA) signaling via LPA receptors (LPA 1 to LPA 6 ) mediates a variety of cellular functions, including cell motility. In the present study, we investigated the effects of LPA receptors on cell motile activity during multi-stage hepatocarcinogenesis in rat liver epithelial WB-F344 cells treated with chemical liver carcinogens. Cells were treated with a initiator (N-nitrosodiethylamine (DEN)) and three promoters (phenobarbital (PB), okadaic acid (OA) and clofibrate) every 24 h for 2 days. Cell motile activity was elevated by DEN, correlating with Lpar3 expression. PB, OA, and clofibrate elevated Lpar1 expression and inhibited cell motile activity. To evaluate the effects of long-term treatment on cell motility, cells were treated with DEN and/or PB for at least 6 months. Lpar3 expression and cell motile activity were significantly elevated by the long-term DEN treatment with or without further PB treatment. In contrast, long-term PB treatment with or without further DEN elevated Lpar1 expression and inhibited cell motility. When the synthesis of extracellular LPA was blocked by a potent ATX inhibitor S32826 before cell motility assay, the cell motility induced by DEN and PB was markedly suppressed. These results suggest that activation of the different LPA receptors may regulate the biological functions of cells treated with chemical carcinogens. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Drug-induced Liver Injury

PubMed Central

David, Stefan; Hamilton, James P

2011-01-01

Drug-induced liver injury (DILI) is common and nearly all classes of medications can cause liver disease. Most cases of DILI are benign, and improve after drug withdrawal. It is important to recognize and remove the offending agent as quickly as possible to prevent the progression to chronic liver disease and/or acute liver failure. There are no definite risk factors for DILI, but pre-existing liver disease and genetic susceptibility may predispose certain individuals. Although most patients have clinical symptoms that are identical to other liver diseases, some patients may present with symptoms of systemic hypersensitivity. Treatment of drug and herbal-induced liver injury consists of rapid drug discontinuation and supportive care targeted to alleviate unwanted symptoms. PMID:21874146

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

PubMed

Gonsebatt, M E; Del Razo, L M; Cerbon, M A; Zúñiga, O; Sanchez-Peña, L C; Ramírez, P

2007-09-01

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 microM 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.

1H NMR-based metabolomics study of liver damage induced by ginkgolic acid (15:1) in mice.

PubMed

Jiang, Lei; Si, Zhi-Hong; Li, Ming-Hui; Zhao, He; Fu, Yong-Hong; Xing, Yue-Xiao; Hong, Wei; Ruan, Ling-Yu; Li, Pu-Min; Wang, Jun-Song

2017-03-20

Ginkgolic acid (15:1) is a major toxic component in extracts obtained from Ginkgo biloba (EGb) that has allergic and genotoxic effects. This study is the first to explore the hepatotoxicity of ginkgolic acid (15:1) using a NMR (nuclear magnetic resonance)-based metabolomics approach in combination with biochemistry assays. Mice were orally administered two doses of ginkgolic acid (15:1), and mouse livers and serum were then collected for NMR recordings and biochemical assays. The levels of activity of alanine aminotransferase (ALT) and glutamic aspartate transaminase (AST) observed in the ginkgolic acid (15:1)-treated mice suggested that it had induced severe liver damage. An orthogonal signal correction partial least-squares discriminant analysis (OSC-PLSDA) performed to determine the metabolomic profile of mouse liver tissues indicated that many metabolic disturbances, especially oxidative stress and purine metabolism, were induced by ginkgolic acid (15:1). A correlation network analysis combined with information related to structural similarities further confirmed that purine metabolism was disturbed by ginkgolic acid (15:1). This mechanism might represent the link between the antitumour activity and the liver injury-inducing effect of ginkgolic acid (15:1). A SUS (Shared and Unique Structure) plot suggested that a two-dose treatment of ginkgolic acid (15:1) had generally the same effect on metabolic variations but that its effects were dose-dependent, revealing some of the common features of ginkgolic acid (15:1) dosing. This integrated metabolomics approach helped us to characterise ginkgolic acid (15:1)-induced liver damage in mice. Copyright © 2016 Elsevier B.V. All rights reserved.

Propolis reduces Leishmania amazonensis-induced inflammation in the liver of BALB/c mice.

PubMed

da Silva, Suelen S; Mizokami, Sandra S; Fanti, Jacqueline R; Miranda, Milena M; Kawakami, Natalia Y; Teixeira, Fernanda Humel; Araújo, Eduardo J A; Panis, Carolina; Watanabe, Maria A E; Sforcin, José M; Pavanelli, Wander R; Verri, Waldiceu A; Felipe, Ionice; Conchon-Costa, Ivete

2016-04-01

Experimental models of mouse paw infection with L. amazonensis show an induction of a strong inflammatory response in the skin, and parasitic migration may occur to secondary organs with consequent tissue injury. There are few studies focusing on the resolution of damage in secondary organs caused by Leishmania species-related cutaneous leishmaniasis. We investigated the propolis treatment effect on liver inflammation induced by Leishmania amazonensis infection in the mouse paw. BALB/c mice were infected in the hind paw with L. amazonensis (10(7)) promastigote forms. After 15 days, animals were treated daily with propolis (5 mg/kg), Glucantime (10 mg/kg), or with propolis plus Glucantime combined. After 60 days, mice were euthanized and livers were collected for inflammatory process analysis. Liver microscopic analysis showed that propolis reduced the inflammatory process compared to untreated infected control. There was a decrease of liver myeloperoxidase and N-acetyl-β-glucosaminidase activity levels, collagen fiber deposition, pro-inflammatory cytokine production, and plasma aspartate transaminase and alanine transaminase levels. Furthermore, propolis treatment enhanced anti-inflammatory cytokine levels and reversed hepatosplenomegaly. Our data demonstrated that daily low doses of Brazilian propolis reduced the secondary chronic inflammatory process in the liver caused by L. amazonensis subcutaneous infection in a susceptible mice strain.

DNA damage in mouse and rat liver by caprolactam and benzoin, evaluated with three different methods.

PubMed

Parodi, S; Abelmoschi, M L; Balbi, C; De Angeli, M T; Pala, M; Russo, P; Taningher, M; Santi, L

1989-11-01

Benzoin and caprolactam were examined for their capability of inducing alkaline DNA fragmentation in mouse and rat liver DNA after treatment in vivo. Three different methods were used. With the alkaline elution technique we measured an effect presumably related to the conformation of the DNA coil. With a viscometric and a fluorometric unwinding method we measured an effect presumably related to the number of unwinding points in DNA. For both compounds only the alkaline elution technique was clearly positive. The results suggest that both caprolactam and benzoin can induce an important change in the conformation of the DNA coil without inducing true breaks in DNA.

Protective Effect of Procyanidin B2 against CCl4-Induced Acute Liver Injury in Mice.

PubMed

Yang, Bing-Ya; Zhang, Xiang-Yu; Guan, Sheng-Wen; Hua, Zi-Chun

2015-07-03

Procyanidin B2 has demonstrated several health benefits and medical properties. However, its protective effects against CCl4-induced hepatotoxicity have not been clarified. The present study aimed to investigate the hepatoprotective effects of procyanidin B2 in CCl4-treated mice. Our data showed that procyanidin B2 significantly decreased the CCl4-induced elevation of serum alanine aminotransferase activities, as well as improved hepatic histopathological abnormalities. Procyanidin B2 also significantly decreased the content of MDA but enhanced the activities of antioxidant enzymes SOD, CAT and GSH-Px. Further research demonstrated that procyanidin B2 decreased the expression of TNF-α, IL-1β, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), as well as inhibited the translocation of nuclear factor-kappa B (NF-κB) p65 from the cytosol to the nuclear fraction in mouse liver. Moreover, CCl4-induced apoptosis in mouse liver was measured by (terminal-deoxynucleotidyl transferase mediated nick end labeling) TUNEL assay and the cleaved caspase-3. Meanwhile, the expression of apoptosis-related proteins Bax and Bcl-xL was analyzed by Western blot. Results showed that procyanidin B2 significantly inhibited CCl4-induced hepatocyte apoptosis, markedly suppressed the upregulation of Bax expression and restored the downregulation of Bcl-xL expression. Overall, the findings indicated that procyanidin B2 exhibited a protective effect on CCl4-induced hepatic injury by elevating the antioxidative defense potential and consequently suppressing the inflammatory response and apoptosis of liver tissues.

Silencing of long noncoding RNA AK139328 attenuates ischemia/reperfusion injury in mouse livers.

PubMed

Chen, Zhenzhen; Jia, Shi; Li, Danhua; Cai, Junyan; Tu, Jian; Geng, Bin; Guan, Youfei; Cui, Qinghua; Yang, Jichun

2013-01-01

Recently, increasing evidences had suggested that long noncoding RNAs (LncRNAs) are involved in a wide range of physiological and pathophysiological processes. Here we determined the LncRNA expression profile using microarray technology in mouse livers after ischemia/reperfusion treatment. Seventy one LncRNAs were upregulated, and 27 LncRNAs were downregulated in ischemia/reperfusion-treated mouse livers. Eleven of the most significantly deregulated LncRNAs were further validated by quantitative PCR assays. Among the upregulated LncRNAs confirmed by quantitative PCR assays, AK139328 exhibited the highest expression level in normal mouse livers. siRNA-mediated knockdown of hepatic AK139328 decreased plasma aminotransferase activities, and reduced necrosis area in the livers with a decrease in caspase-3 activation after ischemia/reperfusion treatment. In ischemia/reperfusion liver, knockdown of AK139328 increased survival signaling proteins including phosphorylated Akt (pAkt), glycogen synthase kinase 3 (pGSK3) and endothelial nitric oxide synthase (peNOS). Furthermore, knockdown of AK139328 also reduced macrophage infitration and inhibited NF-κB activity and inflammatory cytokines expression. In conclusion, these findings revealed that deregulated LncRNAs are involved in liver ischemia/reperfusion injury. Silencing of AK139328 ameliorated ischemia/reperfusion injury in the liver with the activation of Akt signaling pathway and inhibition of NF-κB activity. LncRNA AK139328 might be a novel target for diagnosis and treatment of liver surgery or transplantation.

Examination of the superoxide/hydrogen peroxide forming and quenching potential of mouse liver mitochondria.

PubMed

Slade, Liam; Chalker, Julia; Kuksal, Nidhi; Young, Adrian; Gardiner, Danielle; Mailloux, Ryan J

2017-08-01

Pyruvate dehydrogenase (PDHC) and α-ketoglutarate dehydrogenase complex (KGDHC) are important sources of reactive oxygen species (ROS). In addition, it has been found that mitochondria can also serve as sinks for cellular hydrogen peroxide (H 2 O 2 ). However, the ROS forming and quenching capacity of liver mitochondria has never been thoroughly examined. Here, we show that mouse liver mitochondria use catalase, glutathione (GSH), and peroxiredoxin (PRX) systems to quench ROS. Incubation of mitochondria with catalase inhibitor 3-amino-1,2,4-triazole (triazole) induced a significant increase in pyruvate or α-ketoglutarate driven O 2 - /H 2 O 2 formation. 1-Choro-2,4-dinitrobenzene (CDNB), which depletes glutathione (GSH), elicited a similar effect. Auranofin (AF), a thioredoxin reductase-2 (TR2) inhibitor which disables the PRX system, did not significantly change O 2 - /H 2 O 2 formation. By contrast catalase, GSH, and PRX were all required to scavenging extramitochondrial H 2 O 2 . In this study, the ROS forming potential of PDHC, KGDHC, Complex I, and Complex III was also profiled. Titration of mitochondria with 3-methyl-2-oxovaleric acid (KMV), a specific inhibitor for O 2 - /H 2 O 2 production by KGDHC, induced a ~86% and ~84% decrease in ROS production during α-ketoglutarate and pyruvate oxidation. Titration of myxothiazol, a Complex III inhibitor, decreased O 2 - /H 2 O 2 formation by ~45%. Rotenone also lowered ROS production in mitochondria metabolizing pyruvate or α-ketoglutarate indicating that Complex I does not contribute to ROS production during forward electron transfer from NADH. Taken together, our results indicate that KGDHC and Complex III are high capacity sites for O 2 - /H 2 O 2 production in mouse liver mitochondria. We also confirm that catalase plays a role in quenching either exogenous or intramitochondrial H 2 O 2 . Copyright © 2017 Elsevier B.V. All rights reserved.

Nonacetaminophen Drug-Induced Acute Liver Failure.

PubMed

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.

Promiscuous activity of the LXR antagonist GSK2033 in a mouse model of fatty liver disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Griffett, Kristine; Burris, Thomas P., E-mail: burristp@slu.edu

The liver X receptor (LXR) functions as a receptor for oxysterols and plays a critical role in the regulation of glucose and lipid metabolism. We recently described a synthetic LXR inverse agonist that displayed efficacy in treatment of hepatic steatosis in a mouse model of non-alcoholic fatty liver disease (NAFLD). This compound, SR9238, was designed to display liver specificity so as to avoid potential detrimental effects on reverse cholesterol transport in peripheral tissues. Here, we examined the effects of a LXR antagonist/inverse agonist, GSK2033, which displays systemic exposure. Although GSK2033 performed as expected in cell-based models as a LXR inversemore » agonist, it displayed unexpected activity in the mouse NAFLD model. The expression of lipogenic enzyme genes such as fatty acid synthase and sterol regulatory binding protein 1c were induced rather than suppressed and no effect on hepatic steatosis was found. Further characterization of the specificity of GSK2033 revealed that it displayed a significant degree of promiscuity, targeting a number of other nuclear receptors that could clearly alter hepatic gene expression. - Highlights: • The LXR antagonist GSK2033 suppresses the expression of lipogenic genes FASN and SREBF1 in HepG2 cells. • GSK2033 exhibits sufficient exposure to perform animal experiments targeting the liver. • GSK2033 has fails to suppress hepatic Fasn and Srebf1 expression in an animal model of non-alcoholic fatty liver disease. • GSK2033 may regulate the activity of several nuclear receptors.« less

A study on effects of glutathione s-transferase from silkworm on CCL4-induced mouse liver injury.

PubMed

Yan, Hui; Gui, Zhongzheng; Wang, Bochu

2011-01-01

To assess the hepatoprotective activity of Glutathione S-transferase(GSTsw), extracted and purified from silkworm, in experimental acute mice liver injury and explore mechanisms. Mice were divided into five groups: control group, carbon tetrachloride (CCl4) group, and three treatment groups that received CCl4 and GSTsw at doses of 0.083 mg•g(-1), 0.0415 mg•g(-1) and 0.0207 mg•g(-1) for 3 days. ALT in serum, GST, SOD and T-AOC in liver tissue homogenate, and changes in liver pathology in the five groups were studied. CCl4 administration led to pathological and biochemical evidence of liver injury as compared to untreated controls. GSTsw administration led to significant protection against CCl4-induced changes in liver pathology. It was also associatedwith significantly lower serum ALT levels, higher GST-SOD and T-AOC level in live tissue homogenate. Thus, GSTsw showed protective activity against CCl4-induced hepatotoxicity in mice.

FAT10 IS AN EPIGENETIC MARKER FOR LIVER PRENEOPLASIA IN A DRUG-PRIMED MOUSE MODEL OF TUMORIGENESIS

PubMed Central

Oliva, Joan; Bardag-Gorce, Fawzia; French, Barbara A; Li, Jun; McPhaul, Laron; Amidi, Fataneh; Dedes, Jeniffer; Habibi, Amir; Nguyen, Sheila; French, Samuel W

2010-01-01

There is clinical evidence that chronic liver diseases in which MDBs (Mallory Denk Bodies) form progress to hepatocellular carcinoma. The present study provides evidence that links MDB formation induced by chronic drug injury, with preneoplasia and later to the formation of tumors, which develop long after drug withdrawal. Evidence indicated that this link was due to an epigenetic cellular memory induced by chronic drug ingestion. Microarray analysis showed that the expressions of many markers of preneoplasia (UBD, Alpha Fetoprotein, KLF6 and Glutathione-S-Transferase mu2) were increased together when the drug DDC was refed. These changes were suppressed by S-adenosylmethionine feeding, indicating that the drug was affecting DNA and histones methylation in an epigenetic manner. The link between MDB formation and neoplasia formation was likely due to the over expression of UBD (also called FAT10), which is up regulated in 90% of human hepatocellular carcinomas. Immunohistochemical staining of drug primed mouse livers showed that FAT10 positive liver cells persisted up to 4 months after drug withdrawal and they were still found in the livers of mice, 14 months after drug withdrawal. The refeeding of DDC increased the percent of FAT10 hepatocytes. PMID:18280469

CRISPR-mediated direct mutation of cancer genes in the mouse liver

PubMed Central

Xue, Wen; Chen, Sidi; Yin, Hao; Tammela, Tuomas; Papagiannakopoulos, Thales; Joshi, Nikhil S.; Cai, Wenxin; Yang, Gillian; Bronson, Roderick; Crowley, Denise G.; Zhang, Feng; Anderson, Daniel G.; Sharp, Phillip A.; Jacks, Tyler

2014-01-01

The study of cancer genes in mouse models has traditionally relied on genetically-engineered strains made via transgenesis or gene targeting in embryonic stem (ES) cells1. Here we describe a new method of cancer model generation using the CRISPR/Cas system in vivo in wild-type mice. We have used hydrodynamic injection to deliver a CRISPR plasmid DNA expressing Cas9 and single guide RNAs (sgRNAs)2–4 to the liver and directly target the tumor suppressor genes Pten5 and p536, alone and in combination. CRISPR-mediated Pten mutation led to elevated Akt phosphorylation and lipid accumulation in hepatocytes, phenocopying the effects of deletion of the gene using Cre-LoxP technology7, 8. Simultaneous targeting of Pten and p53 induced liver tumors that mimicked those caused by Cre-loxP-mediated deletion of Pten and p53. DNA sequencing of liver and tumor tissue revealed insertion or deletion (indel) mutations of the tumor suppressor genes, including bi-allelic mutations of both Pten and p53 in tumors. Furthermore, co-injection of Cas9 plasmids harboring sgRNAs targeting the β-Catenin gene (Ctnnb1) and a single-stranded DNA (ssDNA) oligonucleotide donor carrying activating point mutations led to the generation of hepatocytes with nuclear localization of β-Catenin. This study demonstrates the feasibility of direct mutation of tumor suppressor genes and oncogenes in the liver using the CRISPR/Cas system, which presents a new avenue for rapid development of liver cancer models and functional genomics. PMID:25119044

CRISPR-mediated direct mutation of cancer genes in the mouse liver.

PubMed

Xue, Wen; Chen, Sidi; Yin, Hao; Tammela, Tuomas; Papagiannakopoulos, Thales; Joshi, Nikhil S; Cai, Wenxin; Yang, Gillian; Bronson, Roderick; Crowley, Denise G; Zhang, Feng; Anderson, Daniel G; Sharp, Phillip A; Jacks, Tyler

2014-10-16

The study of cancer genes in mouse models has traditionally relied on genetically-engineered strains made via transgenesis or gene targeting in embryonic stem cells. Here we describe a new method of cancer model generation using the CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins) system in vivo in wild-type mice. We used hydrodynamic injection to deliver a CRISPR plasmid DNA expressing Cas9 and single guide RNAs (sgRNAs) to the liver that directly target the tumour suppressor genes Pten (ref. 5) and p53 (also known as TP53 and Trp53) (ref. 6), alone and in combination. CRISPR-mediated Pten mutation led to elevated Akt phosphorylation and lipid accumulation in hepatocytes, phenocopying the effects of deletion of the gene using Cre-LoxP technology. Simultaneous targeting of Pten and p53 induced liver tumours that mimicked those caused by Cre-loxP-mediated deletion of Pten and p53. DNA sequencing of liver and tumour tissue revealed insertion or deletion mutations of the tumour suppressor genes, including bi-allelic mutations of both Pten and p53 in tumours. Furthermore, co-injection of Cas9 plasmids harbouring sgRNAs targeting the β-catenin gene and a single-stranded DNA oligonucleotide donor carrying activating point mutations led to the generation of hepatocytes with nuclear localization of β-catenin. This study demonstrates the feasibility of direct mutation of tumour suppressor genes and oncogenes in the liver using the CRISPR/Cas system, which presents a new avenue for rapid development of liver cancer models and functional genomics.

A microRNA signature for tumorigenic conazoles in mouse liver.

EPA Science Inventory

Triadimefon, propiconazole and myclobutanil are conazoles, an important class of agricultural and therapeutic fungicides. Triadimefon and propiconazole are mouse liver tumorigens, while myclobutanil is not. As part of a coordinated study to understand the molecular determinants o...

Potential preventive effect of carvacrol against diethylnitrosamine-induced hepatocellular carcinoma in rats.

PubMed

Jayakumar, Subramaniyan; Madankumar, Arumugam; Asokkumar, Selvamani; Raghunandhakumar, Subramanian; Gokula dhas, Krishnan; Kamaraj, Sattu; Divya, Michael Georget Josephine; Devaki, Thiruvengadam

2012-01-01

Antioxidants are one of the key players in tumorigenesis, several natural and synthetic antioxidants were shown to have anticancer effects. The aim of the present study is to divulge the chemopreventive nature of carvacrol during diethylnitrosamine (DEN)-induced liver cancer in male wistar albino rats. Administration of DEN to rats resulted in increased relative liver weight and serum marker enzymes aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and gamma glutamyl transpeptidase (γGT). The levels of lipid peroxides elevated (in both serum and tissue) with subsequent decrease in the final body weight and tissue antioxidants like superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione reductase (GR). Carvacrol supplementation (15 mg/kg body weight) significantly attenuated these alterations, thereby showing potent anticancer effect in liver cancer. Histological observations and transmission electron microscopy studies were also carried out, which added supports to the chemopreventive action of the carvacrol against DEN-induction during liver cancer progression. These findings suggest that carvacrol prevents lipid peroxidation, hepatic cell damage, and protects the antioxidant system in DEN-induced hepatocellular carcinogenesis.

Dichlorodiphenyltrichloroethane technical mixture regulates cell cycle and apoptosis genes through the activation of CAR and ERα in mouse livers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kazantseva, Yuliya A.; Yarushkin, Andrei A.; Pustylnyak, Vladimir O., E-mail: pustylnyak@ngs.ru

Dichlorodiphenyltrichloroethane (DDT) is a widely used organochlorine pesticide and a xenoestrogen that promotes rodent hepatomegaly and tumours. A recent study has shown significant correlation between DDT serum concentration and liver cancer incidence in humans, but the underlying mechanisms remain elusive. We hypothesised that a mixture of DDT isomers could exert effects on the liver through pathways instead of classical ERs. The acute effects of a DDT mixture containing the two major isomers p,p′-DDT (85%) and o,p′-DDT (15%) on CAR and ERα receptors and their cell cycle and apoptosis target genes were studied in mouse livers. ChIP results demonstrated increased CARmore » and ERα recruitment to their specific target gene binding sites in response to the DDT mixture. The results of real-time RT-PCR were consistent with the ChIP data and demonstrated that the DDT was able to activate both CAR and ERα in mouse livers, leading to target gene transcriptional increases including Cyp2b10, Gadd45β, cMyc, Mdm2, Ccnd1, cFos and E2f1. Western blot analysis demonstrated increases in cell cycle progression proteins cMyc, Cyclin D1, CDK4 and E2f1 and anti-apoptosis proteins Mdm2 and Gadd45β. In addition, DDT exposure led to Rb phosphorylation. Increases in cell cycle progression and anti-apoptosis proteins were accompanied by a decrease in p53 content and its transcriptional activity. However, the DDT was unable to stimulate the β-catenin signalling pathway, which can play an important role in hepatocyte proliferation. Thus, our results indicate that DDT treatment may result in cell cycle progression and apoptosis inhibition through CAR- and ERα-mediated gene activation in mouse livers. These findings suggest that the proliferative and anti-apoptotic conditions induced by CAR and ERα activation may be important contributors to the early stages of hepatocarcinogenesis as produced by DDT in rodent livers. - Highlights: • DDT activated both CAR and ERα and their

Dietary supplementation with branched-chain amino acids suppresses diethylnitrosamine-induced liver tumorigenesis in obese and diabetic C57BL/KsJ-db/db mice.

PubMed

Iwasa, Junpei; Shimizu, Masahito; Shiraki, Makoto; Shirakami, Yohei; Sakai, Hiroyasu; Terakura, Yoichi; Takai, Koji; Tsurumi, Hisashi; Tanaka, Takuji; Moriwaki, Hisataka

2010-02-01

Obesity and related metabolic abnormalities, including insulin resistance, are risk factors for hepatocellular carcinoma in non-alcoholic steatohepatitis as well as in chronic viral hepatitis. Branched-chain amino acids (BCAA), which improve insulin resistance, inhibited obesity-related colon carcinogenesis in a rodent model, and also reduced the incidence of hepatocellular carcinoma in obese patients with liver cirrhosis. In the present study, we determined the effects of BCAA on the development of diethylnitrosamine (DEN)-induced liver tumorigenesis in obese C57BL/KsJ-db/db (db/db) mice with diabetes mellitus. Male db/db mice were given tap water containing 40 ppm DEN for an initial 2 weeks and thereafter they received a basal diet containing 3.0% of BCAA or casein, which served as a nitrogen content-matched control of BCAA, throughout the experiment. Supplementation with BCAA significantly reduced the total number of foci of cellular alteration, a premalignant lesion of the liver, and the expression of insulin-like growth factor (IGF)-1, IGF-2, and IGF-1 receptor in the liver when compared to the casein supplementation. BCAA supplementation for 34 weeks also significantly inhibited both the development of hepatocellular neoplasms and the proliferation of hepatocytes in comparison to the basal diet or casein-fed groups. Supplementation with BCAA improved liver steatosis and fibrosis and inhibited the expression of alpha-smooth muscle actin in the DEN-treated db/db mice. The serum levels of glucose and leptin decreased by dietary BCAA, whereas the value of the quantitative insulin sensitivity check index increased by this agent, indicating the improvement of insulin resistance and hyperleptinemia. In conclusion, oral BCAA supplementation improves insulin resistance and prevents the development of liver tumorigenesis in obese and diabetic mice.

The Virtual Liver: Modeling Chemical-Induced Liver Toxicity

EPA Science Inventory

The US EPA Virtual Liver (v-Liver) project is aimed at modeling chemical-induced processes in hepatotoxicity and simulating their dose-dependent perturbations. The v-Liver embodies an emerging field of research in computational tissue modeling that integrates molecular and cellul...

Asiatic acid uncouples respiration in isolated mouse liver mitochondria and induces HepG2 cells death.

PubMed

Lu, Yapeng; Liu, Siyuan; Wang, Ying; Wang, Dang; Gao, Jing; Zhu, Li

2016-09-05

Asiatic acid, one of the triterpenoid components isolated from Centella asiatica, has received increasing attention due to a wide variety of biological activities. To date, little is known about its mechanisms of action. Here we examined the cytotoxic effect of asiatic acid on HepG2 cells and elucidated some of the underlying mechanisms. Asiatic acid induced rapid cell death, as well as mitochondrial membrane potential (MMP) dissipation, ATP depletion and cytochrome c release from mitochondria to the cytosol in HepG2 cells. In mitochondria isolated from mouse liver, asiatic acid treatment significantly stimulated the succinate-supported state 4 respiration rate, dissipated the MMP, increased Ca(2+) release from Ca(2+)-loaded mitochondria, decreased ATP content and promoted cytochrome c release, indicating the uncoupling effect of asiatic acid. Hydrogen peroxide (H2O2) produced by succinate-supported mitochondrial respiration was also significantly inhibited by asiatic acid. In addition, asiatic acid inhibited Ca(2+)-induced mitochondrial swelling but did not induce mitochondrial swelling in hyposmotic potassium acetate medium which suggested that asiatic acid may not act as a protonophoric uncoupler. Inhibition of uncoupling proteins (UCPs) or blockade of adenine nucleotide transporter (ANT) attenuated the effect of asiatic acid on MMP dissipation, Ca(2+) release, mitochondrial respiration and HepG2 cell death. When combined inhibition of UCPs and ANT, asiatic acid-mediated uncoupling effect was noticeably alleviated. These results suggested that both UCPs and ANT partially contribute to the uncoupling properties of asiatic acid. In conclusion, asiatic acid is a novel mitochondrial uncoupler and this property is potentially involved in its toxicity on HepG2 cells. Copyright © 2016 Elsevier B.V. All rights reserved.

A Balanced Diet Is Necessary for Proper Entrainment Signals of the Mouse Liver Clock

PubMed Central

Hirao, Akiko; Tahara, Yu; Kimura, Ichiro; Shibata, Shigenobu

2009-01-01

Background The peripheral circadian clock in mice is entrained not only by light-dark cycles but also by daily restricted feeding schedules. Behavioral and cell culture experiments suggest an increase in glucose level as a factor in such feeding-induced entrainment. For application of feeding-induced entrainment in humans, nutrient content and dietary variations should be considered. Principal Finding To elucidate the food composition necessary for dietary entrainment, we examined whether complete or partial substitution of dietary nutrients affected phase shifts in liver clocks of mice. Compared with fasting mice or ad libitum fed mice, the liver bioluminescence rhythm advanced by 3–4 h on the middle day in Per2::luciferase knock-in mice that were administered a standard mouse diet, i.e. AIN-93M formula [0.6–0.85 g/10 g mouse BW] (composition: 14% casein, 47% cornstarch, 15% gelatinized cornstarch, 10% sugar, 4% soybean oil, and 10% other [fiber, vitamins, minerals, etc.]), for 2 days. When each nutrient was tested alone (100% nutrient), an insignificant weak phase advance was found to be induced by cornstarch and soybean oil, but almost no phase advance was induced by gelatinized cornstarch, high-amylose cornstarch, glucose, sucrose, or casein. A combination of glucose and casein without oil, vitamin, or fiber caused a significant phase advance. When cornstarch in AIN-93M was substituted with glucose, sucrose, fructose, polydextrose, high-amylose cornstarch, or gelatinized cornstarch, the amplitude of phase advance paralleled the increase in blood glucose concentration. Conclusions Our results strongly suggest the following: (1) balanced diets containing carbohydrates/sugars and proteins are good for restricted feeding-induced entrainment of the peripheral circadian clock and (2) a balanced diet that increases blood glucose, but not by sugar alone, is suitable for entrainment. These findings may assist in the development of dietary recommendations for on

Distinct anti-oncogenic effect of various microRNAs in different mouse models of liver cancer

PubMed Central

Wu, Heng; Liu, Yan; Wang, XinWei; Calvisi, Diego F.; Song, Guisheng; Chen, Xin

2015-01-01

Deregulation of microRNAs (miRNAs) is a typical feature of human hepatocellular carcinoma (HCC). However, the in vivo relevance of miRNAs along hepatocarcinogenesis remains largely unknown. Here, we show that liver tumors induced in mice by c-Myc overexpression or AKT/Ras co-expression exhibit distinct miRNA expression profiles. Among the downregulated miRNAs, eight (miR-101, miR-107, miR-122, miR-29, miR-365, miR-375, miR-378, and miR-802) were selected and their tumor suppressor activity was determined by overexpressing each of them together with c-Myc or AKT/Ras oncogenes in mouse livers via hydrodynamic transfection. The tumor suppressor activity of these microRNAs was extremely heterogeneous in c-Myc and AKT/Ras mice: while miR-378 had no tumor suppressor activity, miR-107, mir-122, miR-29, miR-365 and miR-802 exhibited weak to moderate tumor suppressor potential. Noticeably, miR-375 showed limited antineoplastic activity against c-Myc driven tumorigenesis, whereas it strongly inhibited AKT/Ras induced hepatocarcinogenesis. Furthermore, miR-101 significantly suppressed both c-Myc and AKT/Ras liver tumor development. Altogether, the present data demonstrate that different oncogenes induce distinct miRNA patterns, whose modulation differently affects hepatocarcinogenesis depending on the driving oncogenes. Finally, our findings support a strong tumor suppressor activity of miR-101 in liver cancer models regardless of the driver oncogenes involved, thus representing a promising therapeutic target in human HCC. PMID:25762642

The organoid-initiating cells in mouse pancreas and liver are phenotypically and functionally similar

PubMed Central

Dorrell, Craig; Tarlow, Branden; Wang, Yuhan; Canaday, Pamela S; Haft, Annelise; Schug, Jonathan; Streeter, Philip R; Finegold, Milton J; Shenje, Lincoln T; Kaestner, Klaus H; Grompe, Markus

2014-01-01

Pancreatic Lgr5 expression has been associated with organoid-forming epithelial progenitor populations but the identity of the organoid-initiating epithelial cell subpopulation has remained elusive. Injury causes the emergence of an Lgr5+ organoid-forming epithelial progenitor population in the adult mouse liver and pancreas. Here, we define the origin of organoid-initiating cells from mouse pancreas and liver prior to Lgr5 activation. This clonogenic population was defined as MIC1-1C3+/CD133+/CD26− in both tissues and the frequency of organoid initiation within this population was approximately 5% in each case. The transcriptomes of these populations overlapped extensively and showed enrichment of epithelial progenitor-associated regulatory genes such as Sox9 and FoxJ1. Surprisingly, pancreatic organoid cells also had the capacity to generate hepatocyte-like cells upon transplantation to Fah-/- mice, indicating a differentiation capacity similar to hepatic organoids. Although spontaneous endocrine differentiation of pancreatic progenitors was not observed in culture, adenoviral delivery of fate-specifying factors Pdx1, Neurog3 and MafA induced insulin expression without glucagon or somatostatin. Pancreatic organoid cultures therefore preserve many key attributes of progenitor cells while allowing unlimited expansion, facilitating the study of fate determination. PMID:25151611

Chronic CCl4 intoxication causes liver and bone damage similar to the human pathology of hepatic osteodystrophy: a mouse model to analyse the liver-bone axis.

PubMed

Nussler, Andreas K; Wildemann, Britt; Freude, Thomas; Litzka, Christian; Soldo, Petra; Friess, Helmut; Hammad, Seddik; Hengstler, Jan G; Braun, Karl F; Trak-Smayra, Viviane; Godoy, Patricio; Ehnert, Sabrina

2014-04-01

Patients with chronic liver diseases frequently exhibit decreased bone mineral densities (BMD), which is defined as hepatic osteodystrophy (HOD). HOD is a multifactorial disease whose regulatory mechanisms are barely understood. Thus, an early diagnosis and therapy is hardly possible. Therefore, the aim of our study consisted in characterizing a mouse model reflecting the human pathomechanism. Serum samples were collected from patients with chronic liver diseases and 12-week old C57Bl6/N mice after 6-week treatment with carbon tetrachloride (CCl4). Repetitive injections of CCl4 induced liver damage in mice, resembling liver fibrosis in patients, as assessed by serum analysis and histological staining. Although CCl4 did not affect primary osteoblast cultures, μCT analysis revealed significantly decreased BMD, bone volume, trabecular number and thickness in CCl4-treated mice. In both HOD patients and CCl4-treated mice, an altered vitamin D metabolism with decreased CYP27A1, CYP2R1, vitamin D-binding protein GC and increased 7-dehydrocholesterol reductase hepatic gene expression, results in decreased 25-OH vitamin D serum levels. Moreover, both groups exhibit excessively high active transforming growth factor-beta (TGF-β) serum levels, inhibiting osteoblast function in vitro. Summarizing, our mouse model presents possible mediators of HOD, e.g. altered vitamin D metabolism and increased active TGF-β. Liver damage and significant changes in bone structure and mineralization are already visible by μCT analysis after 6 weeks of CCl4 treatment. This fast response and easy transferability makes it an ideal model to investigate specific gene functions in HOD.

The effect of trans-ferulic acid and gamma-oryzanol on ethanol-induced liver injury in C57BL mouse.

PubMed

Chotimarkorn, Chatchawan; Ushio, Hideki

2008-11-01

The effects of the oral administration of trans-ferulic acid and gamma-oryzanol (mixture of steryl ferulates) with ethanol (5.0 g per kg) for 30 days to c57BL mice on ethanol-induced liver injury were investigated. Preventions of ethanol-induced liver injury by trans-ferulic acid and gamma-oryzanol were reflected by markedly decreased serum activities of plasma aspartate aminotransferase, alanine aminotransferase and significant decreases in hepatic lipid hydroperoxide and TBARS levels. Furthermore, the trans-ferulic acid- and gamma-oryzanol-treated mice recovered ethanol-induced decrease in hepatic glutathione level together with enhancing superoxide dismutase activity. These results demonstrate that both trans-ferulic acid and gamma-oryzanol exert a protective action on liver injury induced by chronic ethanol ingestion.

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

PubMed

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.

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

PubMed

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.

Liver tumor promoting effect of etofenprox in rats and its possible mechanism of action.

PubMed

Hojo, Yuri; Shiraki, Ayako; Tsuchiya, Takuma; Shimamoto, Keisuke; Ishii, Yuji; Suzuki, Kazuhiko; Shibutani, Makoto; Mitsumori, Kunitoshi

2012-01-01

To investigate the liver tumor-promoting effects of etofenprox (ETF), a pyrethroid-like insecticide, 6 week-old male F344 rats were given an intraperitoneal injection of N-diethylnitrosamine (DEN). After 2 weeks from the DEN treatment, 12 rats per group received a powdered diet containing 0, 0.25, 0.50, or 1.0% ETF for 8 weeks. At the time of 2nd week of ETF administration, all animals were subjected to two-thirds partial hepatectomy (PH). One rat per group except for the 0.25% ETF group died due to surgical operation of PH. The number and area of glutathione S-transferase placental form (GST-P) positive foci significantly increased in the livers of DEN-initiated rats given 0.50% and 1.0% ETF compared with the DEN-alone group. Quantitative real-time RT-PCR analysis revealed that the mRNA expression of phase I enzymes Cyp2b1/2, phase II enzymes such as Akr7a3, Gsta5, Ugt1a6, Nqo1 significantly increased in the DEN+ETF groups. The immunohistochemistry showed the translocation of CAR from the cytoplasm to the nuclei of hepatocytes in the ETF-treated groups. Reactive oxygen species (ROS) production increased in microsomes isolated from the livers of ETF-treated rats, and thiobarbituric acid-reactive substances (TBARS) levels and 8- hydroxy-2-deoxyguanosine (8-OHdG) content significantly increased in all of the ETF-treated groups and DEN+1.0% ETF group, respectively. The results of the present study indicate that ETF has a liver tumor-promoting activity in rats, and suggest that ETF activates the constitutive active/androstane receptor (CAR) and enhances microsomal ROS production, resulting in the upregulation of Nrf2 gene batteries; such an oxidative stress subsequently induces liver tumor-promoting effects by increased cellular proliferation.

Mouse models to study the interaction of risk factors for human liver cancer.

PubMed

Sell, Stewart

2003-11-15

Each of the risk factors for human liver cancer (aflatoxin exposure, hepatitis B virus-associated liver injury, p53 loss, p53ser249 mutation, and male sex) also increases the incidence of hepatocellular carcinoma (HCC) in mouse models of hepatocarcinogenesis. Neonatal mice, partially hepatectomized adult mice, and p53-deficient mice each have a higher hepatocyte proliferation rate, are less able to detoxify AFB1, and form more DNA adducts than do normal wild-type controls. However, transgenic hepatitis B surface antigen mice, expressing hepatitis B surface antigen under control of the albumin promoter (alb/psx), are able to detoxify AFB1 at the same level as do wild-type mice. Thus, AFB1-induced HCC development in neonatal mice and p53+/- mice may be due to "immature" carcinogen metabolism, whereas increased HCC in transgenic hepatitis B virus mice may be due to promotion effects of increased proliferation. Future studies will explore the effects of modifying factors on the development of HCC.

Proteomic analysis of propiconazole responses in mouse liver: comparison of genomic and proteomic profiles

EPA Science Inventory

We have performed for the first time a comprehensive profiling of changes in protein expression of soluble proteins in livers from mice treated with the mouse liver tumorigen, propiconazole, to uncover the pathways and networks altered by this fungicide. Utilizing twodimensional...

Binding of Cimetidine to Balb/C Mouse Liver Catalase; Kinetics and Conformational Studies.

PubMed

Jahangirvand, Mahboubeh; Minai-Tehrani, Dariush; Yazdi, Fatemeh; Minai-Tehrani, Arash; Razmi, Nematollah

2016-01-01

Catalase is responsible for converting hydrogen peroxide (H2O2) into water and oxygen in cells. This enzyme has high affinity for hydrogen peroxide and can protect the cells from oxidative stress damage. Catalase is a tetramer protein and each monomer contains a heme group. Cimetidine is a histamine H2 receptor blocker which inhibits acid release from stomach and is used for gasterointestinal diseases. In this research, effect of cimetidine on the activity of liver catalase was studied and the kinetic parameters of this enzyme and its conformational changes were investigated. Cell free extract of mouse liver was used for the catalase assay. The activity of the catalase was detected in the absence and presence of cimetidine by monitoring hydrogen peroxide reduction absorbance at 240 nm. The purified enzyme was used for conformational studies by Fluorescence spectrophotometry. The data showed that cimetidine could inhibit the enzyme in a non-competitive manner. Ki and IC50 values of the drug were determined to be about 0.75 and 0.85 uM, respectively. The Arrhenius plot showed that activation energy was 6.68 and 4.77 kJ/mol in the presence and absence of the drug, respectively. Fluorescence spectrophotometry revealed that the binding of cimetidine to the purified enzyme induced hyperchromicity and red shift which determined the conformational change on the enzyme. Cimetidine could non-competitively inhibit the liver catalase with high affinity. Binding of cimetidine to the enzyme induced conformational alteration in the enzyme.

Function of GATA Factors in the Adult Mouse Liver

PubMed Central

Zheng, Rena; Rebolledo-Jaramillo, Boris; Zong, Yiwei; Wang, Liqing; Russo, Pierre; Hancock, Wayne; Stanger, Ben Z.; Hardison, Ross C.; Blobel, Gerd A.

2013-01-01

GATA transcription factors and their Friend of Gata (FOG) cofactors control the development of diverse tissues. GATA4 and GATA6 are essential for the expansion of the embryonic liver bud, but their expression patterns and functions in the adult liver are unclear. We characterized the expression of GATA and FOG factors in whole mouse liver and purified hepatocytes. GATA4, GATA6, and FOG1 are the most prominently expressed family members in whole liver and hepatocytes. GATA4 chromatin immunoprecipitation followed by high throughput sequencing (ChIP-seq) identified 4409 occupied sites, associated with genes enriched in ontologies related to liver function, including lipid and glucose metabolism. However, hepatocyte-specific excision of Gata4 had little impact on gross liver architecture and function, even under conditions of regenerative stress, and, despite the large number of GATA4 occupied genes, resulted in relatively few changes in gene expression. To address possible redundancy between GATA4 and GATA6, both factors were conditionally excised. Surprisingly, combined Gata4,6 loss did not exacerbate the phenotype resulting from Gata4 loss alone. This points to the presence of an unusually robust transcriptional network in adult hepatocytes that ensures the maintenance of liver function. PMID:24367609

Curcumin attenuated acute Propionibacterium acnes-induced liver injury through inhibition of HMGB1 expression in mice.

PubMed

Gu, Qiaoli; Guan, Honggeng; Shi, Qin; Zhang, Yanyun; Yang, Huilin

2015-02-01

Curcumin is a phenolic product isolated from the rhizome of Curcuma longa and has protective effects on inflammatory diseases. Here we investigated the protective effect of curcumin in acute Propionibacterium acnes (P. acnes)-induced inflammatory liver injury. C57BL/6 mice were primed with P. acnes followed by LPS challenge to induce fulminant hepatitis. Curcumin or vehicle control was administered perorally by gavage once daily starting 2days before P. acnes priming. We found that curcumin significantly improved mouse mortality. Then, to investigate the underlying mechanisms of curcumin in this acute inflammatory liver injury model, we primed C57BL/6 mice with P. acnes only. We found that curcumin treatment attenuated P. acnes-induced liver injury as evidenced by decreased production of ALT. In addition, curcumin treatment reduced the production of proinflammatory cytokines such as TNF-α and IFN-γ, accompanied by reduced hepatocyte apoptosis. Furthermore, curcumin treatment significantly reduced HMGB1 cytoplasmic translocation and expression by down-regulating acetylation of lysine. Taken together, our results suggest that curcumin protects mice from P. acnes-induced liver injury through reduction of HMGB1 cytoplasmic translocation and expression. Copyright © 2014 Elsevier B.V. All rights reserved.

Fasting-induced liver GADD45β restrains hepatic fatty acid uptake and improves metabolic health.

PubMed

Fuhrmeister, Jessica; Zota, Annika; Sijmonsma, Tjeerd P; Seibert, Oksana; Cıngır, Şahika; Schmidt, Kathrin; Vallon, Nicola; de Guia, Roldan M; Niopek, Katharina; Berriel Diaz, Mauricio; Maida, Adriano; Blüher, Matthias; Okun, Jürgen G; Herzig, Stephan; Rose, Adam J

2016-06-01

Recent studies have demonstrated that repeated short-term nutrient withdrawal (i.e. fasting) has pleiotropic actions to promote organismal health and longevity. Despite this, the molecular physiological mechanisms by which fasting is protective against metabolic disease are largely unknown. Here, we show that, metabolic control, particularly systemic and liver lipid metabolism, is aberrantly regulated in the fasted state in mouse models of metabolic dysfunction. Liver transcript assays between lean/healthy and obese/diabetic mice in fasted and fed states uncovered "growth arrest and DNA damage-inducible" GADD45β as a dysregulated gene transcript during fasting in several models of metabolic dysfunction including ageing, obesity/pre-diabetes and type 2 diabetes, in both mice and humans. Using whole-body knockout mice as well as liver/hepatocyte-specific gain- and loss-of-function strategies, we revealed a role for liver GADD45β in the coordination of liver fatty acid uptake, through cytoplasmic retention of FABP1, ultimately impacting obesity-driven hyperglycaemia. In summary, fasting stress-induced GADD45β represents a liver-specific molecular event promoting adaptive metabolic function. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

A potential microRNA signature for tumorigenic conazoles in mouse liver

EPA Science Inventory

Triadimefon, propiconazole and myclobutanil are conazoles, an important class of agricultural fungicides. Triadimefon and propiconazole are mouse liver tumorigens, while myclobutanil is not. As part of a coordinated study to understand the molecular determinants of conazole tumor...

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

PubMed

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.

Proteomic Analysis of Propiconazole Responses in Mouse Liver-Comparison of Genomic and Proteomic Profiles

EPA Science Inventory

We have performed for the first time a comprehensive profiling of changes in protein expression of soluble proteins in livers from mice treated with the mouse liver tumorigen, propiconazole, to uncover the pathways and networks altered by this commonly used fungicide. Utilizing t...

Glycolytic and gluconeogenic enzyme activities in parenchymal and non-parenchymal cells from mouse liver

PubMed Central

Crisp, D. M.; Pogson, C. I.

1972-01-01

1. Parenchymal cells have been prepared from mouse liver by enzymic and mechanical means. 2. The dry weights, protein and DNA contents of these cells have been determined. 3. Mouse liver `M-' and `L-type' pyruvate kinases have been prepared free of contamination with each other; their kinetic properties have been examined and a method has been developed for their assay in total liver homogenates. 4. Recoveries of phosphoglycerate kinase, lactate dehydrogenase and phosphofructokinase in enzymically prepared cells indicate that little, if any, cytoplasmic protein is lost during preparation. 5. Parenchymal cells exhibit a very substantial increase in the activity ratio of glucokinase to hexokinase over that in total liver homogenate; in three out of eight experiments, hexokinase activity was undetectable. 6. `L-type' pyruvate kinase alone occurs in the parenchymal cell. Non-parenchymal cells are characterized by the presence of `M-type' activity only. 7. Parenchymal cells contain both glucose 6-phosphatase and fructose 1,6-diphosphatase. The non-parenchymal fraction appears to contain fructose 1,6-diphosphatase, but is devoid of glucose 6-phosphatase. 8. No aldolase A was detectable in the whole liver. Aldolase B occurs in both parenchymal and non-parenchymal tissue. 9. Parenchymal cells prepared by mechanical disruption of mouse liver with 20% polyvinyl alcohol exhibit a similar enzyme profile to those prepared enzymically. 10. The methodology involved in the preparation of isolated liver cells is discussed. The importance of the measurement of several parameters as criteria for establishing the viability of parenchymal cells is stressed. 11. The metabolic implications of the results in the present study are discussed. PMID:4262895

Lactobacillus rhamnosus GG Treatment Potentiates Intestinal Hypoxia-Inducible Factor, Promotes Intestinal Integrity and Ameliorates Alcohol-Induced Liver Injury

PubMed Central

Wang, Yuhua; Kirpich, Irina; Liu, Yanlong; Ma, Zhenhua; Barve, Shirish; McClain, Craig J.; Feng, Wenke

2012-01-01

Gut-derived endotoxin is a critical factor in the development and progression of alcoholic liver disease (ALD). Probiotics can treat alcohol-induced liver injury associated with gut leakiness and endotoxemia in animal models, as well as in human ALD; however, the mechanism or mechanisms of their beneficial action are not well defined. We hypothesized that alcohol impairs the adaptive response-induced hypoxia-inducible factor (HIF) and that probiotic supplementation could attenuate this impairment, restoring barrier function in a mouse model of ALD by increasing HIF-responsive proteins (eg, intestinal trefoil factor) and reversing established ALD. C57BJ/6N mice were fed the Lieber DeCarli diet containing 5% alcohol for 8 weeks. Animals received Lactobacillus rhamnosus GG (LGG) supplementation in the last 2 weeks. LGG supplementation significantly reduced alcohol-induced endotoxemia and hepatic steatosis and improved liver function. LGG restored alcohol-induced reduction of HIF-2α and intestinal trefoil factor levels. In vitro studies using the Caco-2 cell culture model showed that the addition of LGG supernatant prevented alcohol-induced epithelial monolayer barrier dysfunction. Furthermore, gene silencing of HIF-1α/2α abolished the LGG effects, indicating that the protective effect of LGG is HIF-dependent. The present study provides a mechanistic insight for utilization of probiotics for the treatment of ALD, and suggests a critical role for intestinal hypoxia and decreased trefoil factor in the development of ALD. PMID:22093263

Isolation of the constitutive heterochromatin from mouse liver nuclei.

PubMed

Zatsepina, Olga V; Zharskaya, Oxana O; Prusov, Andrei N

2008-01-01

A method for isolation of constitutive heterochromatin (chromocenters) from nuclei of mouse liver cells is described. This method is based on the higher resistance of chromocenters to low ionic strength treatment as compared with that of nucleoli and euchromatin. The method allows separation of chromocenters that are essentially free of nucleoli and other nuclear contaminants. In contrast to nuclei and nucleoli, isolated chromocenters are characterized by a simpler protein composition and contain a smaller number of proteins (especially of high molecular weight proteins). They possess telomeric DNA and telomerase activity that suggests a tight association of chromocenters with the telomerase complex in mouse hepatocyte nuclei.

Subchronic effects of valproic acid on gene expression profiles for lipid metabolism in mouse liver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Min-Ho; Kim, Mingoo; Lee, Byung-Hoon

2008-02-01

Valproic acid (VPA) is used clinically to treat epilepsy, however it induces hepatotoxicity such as microvesicular steatosis. Acute hepatotoxicity of VPA has been well documented by biochemical studies and microarray analysis, but little is known about the chronic effects of VPA in the liver. In the present investigation, we profiled gene expression patterns in the mouse liver after subchronic treatment with VPA. VPA was administered orally at a dose of 100 mg/kg/day or 500 mg/kg/day to ICR mice, and the livers were obtained after 1, 2, or 4 weeks. The activities of serum liver enzymes did not change, whereas triglyceridemore » concentration increased significantly. Microarray analysis revealed that 1325 genes of a set of 32,996 individual genes were VPA responsive when examined by two-way ANOVA (P < 0.05) and fold change (> 1.5). Consistent with our previous results obtained using an acute VPA exposure model (Lee et al., Toxicol Appl Pharmacol. 220:45-59, 2007), the most significantly over-represented biological terms for these genes included lipid, fatty acid, and steroid metabolism. Biological pathway analysis suggests that the genes responsible for increased biosynthesis of cholesterol and triglyceride, and for decreased fatty acid {beta}-oxidation contribute to the abnormalities in lipid metabolism induced by subchronic VPA treatment. A comparison of the VPA-responsive genes in the acute and subchronic models extracted 15 commonly altered genes, such as Cyp4a14 and Adpn, which may have predictive power to distinguish the mode of action of hepatotoxicants. Our data provide a better understanding of the molecular mechanisms of VPA-induced hepatotoxicity and useful information to predict steatogenic hepatotoxicity.« less

A novel method of mouse ex utero transplantation of hepatic progenitor cells into the fetal liver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shikanai, Mima; Asahina, Kinji; Iseki, Sachiko

2009-04-03

Avoiding the limitations of the adult liver niche, transplantation of hepatic stem/progenitor cells into fetal liver is desirable to analyze immature cells in a hepatic developmental environment. Here, we established a new monitor tool for cell fate of hepatic progenitor cells transplanted into the mouse fetal liver by using ex utero surgery. When embryonic day (ED) 14.5 hepatoblasts were injected into the ED14.5 fetal liver, the transplanted cells expressed albumin abundantly or {alpha}-fetoprotein weakly, and contained glycogen in the neonatal liver, indicating that transplanted hepatoblasts can proliferate and differentiate in concord with surrounding recipient parenchymal cells. The transplanted cells becamemore » mature in the liver of 6-week-old mice. Furthermore, this method was applicable to transplantation of hepatoblast-like cells derived from mouse embryonic stem cells. These data indicate that this unique technique will provide a new in vivo experimental system for studying cell fate of hepatic stem/progenitor cells and liver organogenesis.« less

Reduced 4-Aminobiphenyl-Induced Liver Tumorigenicity but not DNA Damage in Arylamine N-Acetyltransferase Null Mice

PubMed Central

Sugamori, Kim S.; Brenneman, Debbie; Sanchez, Otto; Doll, Mark A.; Hein, David W.; Pierce, William M.; Grant, Denis M.

2012-01-01

The aromatic amine 4-aminobiphenyl (ABP) is a liver procarcinogen in mice, requiring enzymatic bioactivation to exert its tumorigenic effect. To assess the role of arylamine N-acetyltransferase (NAT)-dependent acetylation capacity in the risk for ABP-induced liver tumors, we compared 1-year liver tumor incidence following the postnatal exposure of wild-type and NAT-deficient Nat1/2(−/−) mice to ABP. At an ABP exposure of 1200 nmoles, male Nat1/2(−/−) mice had a liver tumor incidence of 36% compared to 69% in wild-type males, and at 600 nmoles there was a complete absence of tumors compared to 60% in wild-type mice. Only one female wild-type mouse had a tumor using this exposure protocol. However, levels of N-deoxyguanosin-8-yl-ABP-DNA adducts did not correlate with either the strain or sex differences in tumor incidence. These results suggest that female sex and NAT deficiency reduce risk for ABP-induced liver tumors, but by mechanisms unrelated to differences in DNA-damaging events. PMID:22193722

Non-alcoholic fatty liver disease (NAFLD) potentiates autoimmune hepatitis in the CYP2D6 mouse model.

PubMed

Müller, Peter; Messmer, Marie; Bayer, Monika; Pfeilschifter, Josef M; Hintermann, Edith; Christen, Urs

2016-05-01

Non-alcoholic fatty liver disease (NAFLD) and its more severe development non-alcoholic steatohepatitis (NASH) are increasing worldwide. In particular NASH, which is characterized by an active hepatic inflammation, has often severe consequences including progressive fibrosis, cirrhosis, and eventually hepatocellular carcinoma (HCC). Here we investigated how metabolic liver injury is influencing the pathogenesis of autoimmune hepatitis (AIH). We used the CYP2D6 mouse model in which wild type C57BL/6 mice are infected with an Adenovirus expressing the major liver autoantigen cytochrome P450 2D6 (CYP2D6). Such mice display several features of human AIH, including interface hepatitis, formation of LKM-1 antibodies and CYP2D6-specific T cells, as well as hepatic fibrosis. NAFLD was induced with a high-fat diet (HFD). We found that pre-existing NAFLD potentiates the severity of AIH. Mice fed for 12 weeks with a HFD displayed increased cellular infiltration of the liver, enhanced hepatic fibrosis and elevated numbers of liver autoantigen-specific T cells. Our data suggest that a pre-existing metabolic liver injury constitutes an additional risk for the severity of an autoimmune condition of the liver, such as AIH. Copyright © 2016 Elsevier Ltd. All rights reserved.

Discrimination of tumorigenic triazole conazoles from phenobarbital by transcriptional analyses of mouse liver gene expression

EPA Science Inventory

Conazoles are fungicides used to control fungal growth in environmental settings and to treat humans with fungal infections. Mouse hepatotumorigenic conazoles display many of the same hepatic toxicologic responses as the mouse liver carcinogen phenobarbital (PB): constitutive and...

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

PubMed

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

2016-09-01

Chimeric mouse liver models are useful in vivo tools for human drug metabolism studies; however, liver integrity and the microcirculation remain largely uninvestigated. Hence, we conducted liver perfusion studies to examine these attributes in FRGN [Fah(-/-), Rag2(-/-), and Il2rg(-/-), NOD strain] livers (control) and chimeric livers repopulated with mouse (mFRGN) or human (hFRGN) hepatocytes. In single-pass perfusion studies (2.5 ml/min), outflow dilution profiles of noneliminated reference indicators ((51)Cr-RBC, (125)I-albumin, (14)C-sucrose, and (3)H-water) revealed preservation of flow-limited distribution and reduced water and albumin spaces in hFRGN livers compared with FRGN livers, a view supported microscopically by tightly packed sinusoids. With prograde and retrograde perfusion of harmol (50 µM) in FRGN livers, an anterior sulfation (Sult1a1) over the posterior distribution of glucuronidation (Ugt1a1) activity was preserved, evidenced by the 42% lower sulfation-to-glucuronidation ratio (HS/HG) and 14% higher harmol extraction ratio (E) upon switching from prograde to retrograde flow. By contrast, zonation was lost in mFRGN and hFRGN livers, with HS/HG and E for both flows remaining unchanged. Remnant mouse genes persisted in hFRGN livers (10%-300% those of FRGN). When hFRGN livers were compared with human liver tissue, higher UGT1A1 and MRP2, lower MRP3, and unchanged SULT1A1 and MRP4 mRNA expression were observed. Total Sult1a1/SULT1A1 protein expression in hFRGN livers was higher than that of FRGN livers, consistent with higher harmol sulfate formation. The composite data on humanized livers suggest a loss of zonation, lack of complete liver humanization, and persistence of murine hepatocyte activities leading to higher sulfation. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Deletion of sphingosine kinase 1 inhibits liver tumorigenesis in diethylnitrosamine-treated mice

PubMed Central

Chen, Jinbiao; Qi, Yanfei; Zhao, Yang; Kaczorowski, Dominik; Couttas, Timothy A.; Coleman, Paul R.; Don, Anthony S.; Bertolino, Patrick; Gamble, Jennifer R.; Vadas, Mathew A.; Xia, Pu; McCaughan, Geoffrey W.

2018-01-01

Primary liver cancer is the 3rd leading cause of cancer deaths worldwide with very few effective treatments. Sphingosine kinase 1 (SphK1), a key regulator of sphingolipid metabolites, is over-expressed in human hepatocellular carcinoma (HCC) and our previous studies have shown that SphK1 is important in liver injury. We aimed to explore the role of SphK1 specifically in liver tumorigenesis using the SphK1 knockout (SphK1−/−) mouse. SphK1 deletion significantly reduced the number and the size of DEN-induced liver cancers in mice. Mechanistically, fewer proliferating but more apoptotic and senescent cells were detected in SphK1 deficient tumors compared to WT tumors. There was an increase in sphingosine rather than a decrease in sphingosine 1-phosphate (S1P) in SphK1 deficient tumors. Furthermore, the STAT3-S1PR pathway that has been reported previously to mediate the effect of SphK1 on colorectal cancers was not altered by SphK1 deletion in liver cancer. Instead, c-Myc protein expression was down-regulated by SphK1 deletion. In conclusion, this is the first in vivo evidence that SphK1 contributes to hepatocarcinogenesis. However, the downstream signaling pathways impacting on the development of HCC via SphK1 are organ specific providing further evidence that simply transferring known oncogenic molecular pathway targeting into HCC is not always valid. PMID:29643998

Propylthiouracil-Induced Acute Liver Failure: Role of Liver Transplantation

PubMed Central

Carrion, Andres F.; Czul, Frank; Arosemena, Leopoldo R.; Selvaggi, Gennaro; Garcia, Monica T.; Tekin, Akin; Tzakis, Andreas G.; Martin, Paul; Ghanta, Ravi K.

2010-01-01

Propylthiouracil- (PTU-) induced hepatotoxicity is rare but potentially lethal with a spectrum of liver injury ranging from asymptomatic elevation of transaminases to fulminant hepatic failure and death. We describe two cases of acute hepatic failure due to PTU that required liver transplantation. Differences in the clinical presentation, histological characteristics, and posttransplant management are described as well as alternative therapeutic options. Frequent monitoring for PTU-induced hepatic dysfunction is strongly advised because timely discontinuation of this drug and implementation of noninvasive therapeutic interventions may prevent progression to liver failure or even death. PMID:21234410

ACB-PCR measurement of spontaneous and furan-induced H-ras codon 61 CAA to CTA and CAA to AAA mutation in B6C3F1 mouse liver.

PubMed

Banda, Malathi; Recio, Leslie; Parsons, Barbara L

2013-10-01

Furan is a rodent liver carcinogen, but the mode of action for furan hepatocarcinogenicity is unclear. H-ras codon 61 mutations have been detected in spontaneous liver tumors of B6C3F1 mice, and the fraction of liver tumors carrying H-ras codon 61 CAA to AAA mutation increased in furan-treated mice. Allele-specific competitive blocker PCR (ACB-PCR) has been used previously to quantify early, carcinogen-induced increases in tumor-associated mutations. The present pilot study investigated whether furan drives clonal expansion of pre-existing H-ras mutant cells in B6C3F1 mouse liver. H-ras codon 61 CAA to CTA and CAA to AAA mutations were measured in DNA isolated from liver tissue of female mice treated with 0, 1, 2, 4, or 8 mg furan/kg body weight, five days per week for three weeks, using five mice per treatment group. Spontaneous levels of mutation were low, with two of five control mice having an H-ras codon 61 CTA or AAA mutant fraction (MF) greater than 10(-5) . Several furan-treated mice had H-ras codon 61 AAA or CTA MFs greater than those measured in control mice and lower bound estimates of induced MF were calculated. However, no statistically-significant differences were observed between treatment groups. Therefore, while sustained exposure to furan is carcinogenic, at the early stage of carcinogenesis examined in this study (three weeks), there was not a significant expansion of H-ras mutant cells. Copyright © 2013 Wiley Periodicals, Inc.

Selective inhibitor of Wnt/β-catenin/CBP signaling ameliorates hepatitis C virus-induced liver fibrosis in mouse model.

PubMed

Tokunaga, Yuko; Osawa, Yosuke; Ohtsuki, Takahiro; Hayashi, Yukiko; Yamaji, Kenzaburo; Yamane, Daisuke; Hara, Mitsuko; Munekata, Keisuke; Tsukiyama-Kohara, Kyoko; Hishima, Tsunekazu; Kojima, Soichi; Kimura, Kiminori; Kohara, Michinori

2017-03-23

Chronic hepatitis C virus (HCV) infection is one of the major causes of serious liver diseases, including liver cirrhosis. There are no anti-fibrotic drugs with efficacy against liver cirrhosis. Wnt/β-catenin signaling has been implicated in the pathogenesis of a variety of tissue fibrosis. In the present study, we investigated the effects of a β-catenin/CBP (cyclic AMP response element binding protein) inhibitor on liver fibrosis. The anti-fibrotic activity of PRI-724, a selective inhibitor of β-catenin/CBP, was assessed in HCV GT1b transgenic mice at 18 months after HCV genome expression. PRI-724 was injected intraperitoneally or subcutaneously in these mice for 6 weeks. PRI-724 reduced liver fibrosis, which was indicated by silver stain, Sirius Red staining, and hepatic hydroxyproline levels, in HCV mice while attenuating αSMA induction. PRI-724 led to increased levels of matrix metalloproteinase (MMP)-8 mRNA in the liver, along with elevated levels of intrahepatic neutrophils and macrophages/monocytes. The induced intrahepatic neutrophils and macrophages/monocytes were identified as the source of MMP-8. In conclusion, PRI-724 ameliorated HCV-induced liver fibrosis in mice. We hypothesize that inhibition of hepatic stellate cells activation and induction of fibrolytic cells expressing MMP-8 contribute to the anti-fibrotic effects of PRI-724. PRI-724 is a drug candidate which possesses anti-fibrotic effect.

Effects of rutin supplementation on antioxidant status and iron, copper, and zinc contents in mouse liver and brain.

PubMed

Gao, Zhonghong; Xu, Huibi; Huang, Kaixun

2002-09-01

The effect of rutin on total antioxidant status as well as on trace elements such as iron, copper, and zinc in mouse liver and brain were studied. Mice were administrated with 0.75 g/kg or 2.25 g/kg P. O. of rutin for 30 d consecutively. Following the treatment, the activity of total antioxidant status, catalase, Cu,Zn-superoxide dismutase, Mn-superoxide dismutase, zinc, copper, and iron were measured in mouse liver and brain. The results showed that rutin significantly increased the antioxidant status and Mn-superoxide dismutase activities in mouse liver, but it had no effect on these variables in the brain. Treatment with a higher concentration of rutin significantly decreased catalase activity and iron, zinc, and copper contents in mouse liver; it also resulted in a slower weight gain for the first 20 d. These results indicate that rutin taken in proper amount can effectively improve antioxidant status, whereas at an increased dosage, it may cause trace element (such as iron, zinc, and copper) deficiencies and a decrease in the activities of related metal-containing enzymes.

Ursodeoxycholic Acid Suppresses Lipogenesis in Mouse Liver: Possible Role of the Decrease in β-Muricholic Acid, a Farnesoid X Receptor Antagonist.

PubMed

Fujita, Kyosuke; Iguchi, Yusuke; Une, Mizuho; Watanabe, Shiro

2017-04-01

The farnesoid X receptor (FXR) is a major nuclear receptor of bile acids; its activation suppresses sterol regulatory element-binding protein 1c (SREBP1c)-mediated lipogenesis and decreases the lipid contents in the liver. There are many reports showing that the administration of ursodeoxycholic acid (UDCA) suppresses lipogenesis and reduces the lipid contents in the liver of experimental animals. Since UDCA is not recognized as an FXR agonist, these effects of UDCA cannot be readily explained by its direct activation of FXR. We observed that the dietary administration of UDCA in mice decreased the expression levels of SREBP1c and its target lipogenic genes. Alpha- and β-muricholic acids (MCA) and cholic acid (CA) were the major bile acids in the mouse liver but their contents decreased upon UDCA administration. The hepatic contents of chenodeoxycholic acid and deoxycholic acid (DCA) were relatively low but were not changed by UDCA. UDCA did not show FXR agonistic or antagonistic potency in in vitro FXR transactivation assay. Taking these together, we deduced that the above-mentioned change in hepatic bile acid composition induced upon UDCA administration might cause the relative increase in the FXR activity in the liver, mainly by the reduction in the content of β-MCA, a farnesoid X receptor antagonist, which suggests a mechanism by which UDCA suppresses lipogenesis and decreases the lipid contents in the mouse liver.

Peroxisome proliferator activated receptor alpha regulates a male-specific cytochrome P450 in mouse liver.

PubMed

Jeffery, Brett; Choudhury, Agharul I; Horley, Neill; Bruce, Mary; Tomlinson, Simon R; Roberts, Ruth A; Gray, Tim J B; Barrett, David A; Shaw, P Nicholas; Kendall, David; Bell, David R

2004-09-15

We set out to find if the strain-specific, male-specific hepatic expression of Cyp4a protein in mouse was due to expression of Cyp4a12 and to understand the genetic basis for reported differences in expression. 12-Lauric acid hydroxylase (LAH) activity was found to show higher levels in male ddY, but not C57Bl/6, mouse liver microsomes. The expression of Cyp4a12 mRNA was studied using RNAase protection assays in male and female liver and kidney of nine mouse strains. Cyp4a12 was found to be highly expressed in male liver and kidney, but at much lower levels in female liver and kidney, in all strains studied. Western blotting with an antibody specific for Cyp4a12 confirmed that Cyp4a12 was expressed in a male specific fashion in C57Bl/6 mouse liver. RNAase protection analysis for Cyp4a10 and 14 in ddY mice revealed that neither of these genes showed male-specific expression. To further investigate genetic factors that control male-specific Cyp4a12 expression, PPARalpha+/+ and -/- mice were studied, showing that total P450 and 12-LAH activity was male-specific in +/+, but not -/- mice. RNAase protection assays were used to confirm that Cyp4a12 was lower in -/- mice. However, the male-specific Slp and MUP-1 genes retained hepatic male-specific levels of expression in +/+ and -/- mice, showing that the decrease in Cyp4a12 was not a general effect on male-specific expression. Thus, PPARalpha has a specific effect on constitutive expression of Cyp4a12.

Collagen-binding vascular endothelial growth factor attenuates CCl4-induced liver fibrosis in mice

PubMed Central

Wu, Kangkang; Huang, Rui; Wu, Hongyan; Liu, Yong; Yang, Chenchen; Cao, Shufeng; Hou, Xianglin; Chen, Bing; Dai, Jianwu; Wu, Chao

2016-01-01

Vascular endothelial growth factor (VEGF) serves an important role in promoting angiogenesis and tissue regeneration. However, the lack of an effective delivery system that can target this growth factor to the injured site reduces its therapeutic efficacy. Therefore, in the current study, collagen-binding VEGF was constructed by fusing a collagen-binding domain (CBD) to the N-terminal of native VEGF. The CBD-VEGF can specifically bind to collagen which is the major component of the extracellular matrix in fibrotic liver. The anti-fibrotic effects of this novel material were investigated by the carbon tetrachloride (CCl4)-induced liver fibrotic mouse model. Mice were injected with CCl4 intraperitoneally to induce liver fibrosis. CBD-VEGF was injected directly into the liver tissue of mice. The liver tissues were stained with hematoxylin and eosin for general observation or with Masson's trichrome staining for detection of collagen deposition. The hepatic stellate cell activation, blood vessel formation and hepatocyte proliferation were measured by immunohistochemical staining for α-smooth muscle actin, CD31 and Ki67 in the liver tissue. The fluorescent TUNEL assay was performed to evaluate the hepatocyte apoptosis. The present study identified that the CBD-VEGF injection could significantly promote vascularization of the liver tissue of fibrotic mice and attenuate liver fibrosis. Furthermore, hepatocyte apoptosis and hepatic stellate cell activation were attenuated by CBD-VEGF treatment. CBD-VEGF treatment could additionally promote hepatocyte regeneration in the liver tissue of fibrotic mice. Thus, it was suggested that CBD-VEGF may be used as a novel therapeutic intervention for liver fibrosis. PMID:27748931

Preventing Drug-Induced Liver Injury: How Useful Are Animal Models?

PubMed

Ballet, François

2015-01-01

Drug-induced liver injury (DILI) is the most common organ toxicity encountered in regulatory animal toxicology studies required prior to the clinical development of new drug candidates. Very few reports have evaluated the value of these studies for predicting DILI in humans. Indeed, compounds inducing liver toxicity in regulatory toxicology studies are not always correlated with a risk of DILI in humans. Conversely, compounds associated with the occurrence of DILI in phase 3 studies or after market release are often tested negative in regulatory toxicology studies. Idiosyncratic DILI is a rare event that is precipitated in an individual by the simultaneous occurrence of several critical factors. These factors may relate to the host (e.g. human leukocyte antigen polymorphism, inflammation), the drug (e.g. reactive metabolites) or the environment (e.g. diet/microbiota). This type of toxicity therefore cannot be detected in conventional animal toxicology studies. Several animal models have recently been proposed for the identification of drugs with the potential to cause idiosyncratic DILI: rats treated with lipopolysaccharide, Sod2(+/-) mice, panels of inbred mouse strains or chimeric mice with humanized livers. These models are not suitable for use in the prospective screening of new drug candidates. Humans therefore constitute the best model for predicting and assessing idiopathic DILI. © 2015 S. Karger AG, Basel.

Liver proteomics for therapeutic drug discovery: inhibition of the cyclophilin receptor CD147 attenuates sepsis-induced acute renal failure

PubMed Central

Dear, James W.; Leelahavanichkul, Asada; Aponte, Angel; Hu, Xuzhen; Constant, Stephanie L.; Hewitt, Stephen M.; Yuen, Peter S.T.; Star, Robert A.

2008-01-01

Objective Sepsis-induced multi-organ failure continues to have a high mortality. The liver is an organ central to the disease pathogenesis. The objective of this study was to identify the liver proteins that change in abundance with sepsis and, therefore, identify new drug targets. Design Proteomic discovery study and drug target validation Setting Research institute laboratory Subjects Three month old C57BL/6 mice Interventions We used a mouse model of sepsis based on cecal ligation and puncture (CLP) but with fluid and antibiotic resuscitation. Liver proteins that changed in abundance were identified by difference in-gel electrophoresis (DIGE). We compared liver proteins from 6 hr post-CLP to sham-operated mice (‘early proteins’) and 24 hr post-CLP with 6 hr post-CLP (‘late proteins’). Proteins that changed in abundance were identified by tandem mass spectrometry. We then inhibited the receptor for one protein and determined the effect on sepsis-induced organ dysfunction. Results The liver proteins that changed in abundance after sepsis had a range of functions such as acute phase proteins, coagulation, ER stress, oxidative stress, apoptosis, mitochondrial proteins and nitric oxide metabolism. We found that cyclophilin increased in abundance after CLP. When the receptor for this protein, CD147, was inhibited sepsis-induced renal dysfunction was reduced. There was also a significant reduction in serum cytokine production when CD147 was inhibited. Conclusion By applying proteomics to a clinically relevant mouse model of sepsis we identified a number of novel proteins that changed in abundance. The inhibition of the receptor for one of these proteins, cyclophilin, attenuated sepsis-induced acute renal failure. The application of proteomics to sepsis research can facilitate the discovery of new therapeutic targets. PMID:17944020

Proteome analysis of a hepatocyte-specific BIRC5 (survivin)-knockout mouse model during liver regeneration.

PubMed

Bracht, Thilo; Hagemann, Sascha; Loscha, Marius; Megger, Dominik A; Padden, Juliet; Eisenacher, Martin; Kuhlmann, Katja; Meyer, Helmut E; Baba, Hideo A; Sitek, Barbara

2014-06-06

The Baculoviral IAP repeat-containing protein 5 (BIRC5), also known as inhibitor of apoptosis protein survivin, is a member of the chromosomal passenger complex and a key player in mitosis. To investigate the function of BIRC5 in liver regeneration, we analyzed a hepatocyte-specific BIRC5-knockout mouse model using a quantitative label-free proteomics approach. Here, we present the analyses of the proteome changes in hepatocyte-specific BIRC5-knockout mice compared to wildtype mice, as well as proteome changes during liver regeneration induced by partial hepatectomy in wildtype mice and mice lacking hepatic BIRC5, respectively. The BIRC5-knockout mice showed an extensive overexpression of proteins related to cellular maintenance, organization and protein synthesis. Key regulators of cell growth, transcription and translation MTOR and STAT1/STAT2 were found to be overexpressed. During liver regeneration proteome changes representing a response to the mitotic stimulus were detected in wildtype mice. Mainly proteins corresponding to proliferation, cell cycle and cytokinesis were up-regulated. The hepatocyte-specific BIRC5-knockout mice showed impaired liver regeneration, which had severe consequences on the proteome level. However, several proteins with function in mitosis were found to be up-regulated upon the proliferative stimulus. Our results show that the E3 ubiquitin-protein ligase UHRF1 is strongly up-regulated during liver regeneration independently of BIRC5.

Zinc supplementation suppresses the progression of bile duct ligation-induced liver fibrosis in mice.

PubMed

Shi, Fang; Sheng, Qin; Xu, Xinhua; Huang, Wenli; Kang, Y James

2015-09-01

Metallothionein (MT) gene therapy leads to resolution of liver fibrosis in mouse model, in which the activation of collagenases is involved in the regression of liver fibrosis. MT plays a critical role in zinc sequestration in the liver suggesting its therapeutic effect would be mediated by zinc. The present study was undertaken to test the hypothesis that zinc supplementation suppresses liver fibrosis. Male Kunming mice subjected to bile duct ligation (BDL) resulted in liver fibrosis as assessed by increased α-smooth muscle actin (α-SMA) and collagen I production/deposition in the liver. Zinc supplementation was introduced 4 weeks after BDL surgery via intragastric administration once daily for 2 weeks resulting in a significant reduction in the collagen deposition in the liver and an increase in the survival rate. Furthermore, zinc suppressed gene expression of α-SMA and collagen I and enhanced the capacity of collagen degradation, as determined by the increased activity of total collagenases and elevated mRNA and protein levels of MMP13. Therefore, the results demonstrate that zinc supplementation suppresses BDL-induced liver fibrosis through both inhibiting collagen production and enhancing collagen degradation. © 2014 by the Society for Experimental Biology and Medicine.

Uridine prevents tamoxifen-induced liver lipid droplet accumulation

PubMed Central

2014-01-01

Background Tamoxifen, an agonist of estrogen receptor, is widely prescribed for the prevention and long-term treatment of breast cancer. A side effect of tamoxifen is fatty liver, which increases the risk for non-alcoholic fatty liver disease. Prevention of tamoxifen-induced fatty liver has the potential to improve the safety of long-term tamoxifen usage. Methods Uridine, a pyrimidine nucleoside with reported protective effects against drug-induced fatty liver, was co-administered with tamoxifen in C57BL/6J mice. Liver lipid levels were evaluated with lipid visualization using coherent anti-Stokes Raman scatting (CARS) microscopy, biochemical assay measurement of triacylglyceride (TAG), and liquid chromatography coupled with mass spectrometry (LC-MS) measurement of membrane phospholipid. Blood TAG and cholesterol levels were measured. Mitochondrial respiration of primary hepatocytes in the presence of tamoxifen and/or uridine was evaluated by measuring oxygen consumption rate with an extracellular flux analyzer. Liver protein lysine acetylation profiles were evaluated with 1D and 2D Western blots. In addition, the relationship between endogenous uridine levels, fatty liver, and tamoxifen administration was evaluated in transgenic mice UPase1−/−and UPase1-TG. Results Uridine co-administration prevented tamoxifen-induced liver lipid droplet accumulation in mice. The most prominent effect of uridine co-administration with tamoxifen was the stimulation of liver membrane phospholipid biosynthesis. Uridine had no protective effect against tamoxifen-induced impairment to mitochondrial respiration of primary hepatocytes or liver TAG and cholesterol export. Uridine had no effect on tamoxifen-induced changes to liver protein acetylation profile. Transgenic mice UPase1−/−with increased pyrimidine salvage activity were protected against tamoxifen-induced liver lipid droplet accumulation. In contrast, UPase1-TG mice with increased pyrimidine catabolism activity had

Uridine prevents tamoxifen-induced liver lipid droplet accumulation.

PubMed

Le, Thuc T; Urasaki, Yasuyo; Pizzorno, Giuseppe

2014-05-23

Tamoxifen, an agonist of estrogen receptor, is widely prescribed for the prevention and long-term treatment of breast cancer. A side effect of tamoxifen is fatty liver, which increases the risk for non-alcoholic fatty liver disease. Prevention of tamoxifen-induced fatty liver has the potential to improve the safety of long-term tamoxifen usage. Uridine, a pyrimidine nucleoside with reported protective effects against drug-induced fatty liver, was co-administered with tamoxifen in C57BL/6J mice. Liver lipid levels were evaluated with lipid visualization using coherent anti-Stokes Raman scatting (CARS) microscopy, biochemical assay measurement of triacylglyceride (TAG), and liquid chromatography coupled with mass spectrometry (LC-MS) measurement of membrane phospholipid. Blood TAG and cholesterol levels were measured. Mitochondrial respiration of primary hepatocytes in the presence of tamoxifen and/or uridine was evaluated by measuring oxygen consumption rate with an extracellular flux analyzer. Liver protein lysine acetylation profiles were evaluated with 1D and 2D Western blots. In addition, the relationship between endogenous uridine levels, fatty liver, and tamoxifen administration was evaluated in transgenic mice UPase1-/-and UPase1-TG. Uridine co-administration prevented tamoxifen-induced liver lipid droplet accumulation in mice. The most prominent effect of uridine co-administration with tamoxifen was the stimulation of liver membrane phospholipid biosynthesis. Uridine had no protective effect against tamoxifen-induced impairment to mitochondrial respiration of primary hepatocytes or liver TAG and cholesterol export. Uridine had no effect on tamoxifen-induced changes to liver protein acetylation profile. Transgenic mice UPase1-/-with increased pyrimidine salvage activity were protected against tamoxifen-induced liver lipid droplet accumulation. In contrast, UPase1-TG mice with increased pyrimidine catabolism activity had intrinsic liver lipid droplet

Diethylnitrosamine-induced hepatocarcinogenesis is suppressed in lecithin:retinol acyltransferase-deficient mice primarily through retinoid actions immediately after carcinogen administration.

PubMed

Shirakami, Yohei; Gottesman, Max E; Blaner, William S

2012-02-01

Loss of retinoid-containing lipid droplets upon hepatic stellate cell (HSC) activation is one of the first events in the development of liver disease leading to hepatocellular carcinoma. Although retinoid stores are progressively lost from HSCs during the development of hepatic disease, how this affects hepatocarcinogenesis is unclear. To investigate this, we used diethylnitrosamine (DEN) to induce hepatic tumorigenesis in matched wild-type (WT) and lecithin:retinol acyltransferase (LRAT) knockout (KO) mice, which lack stored retinoid and HSC lipid droplets. Male 15-day-old WT or Lrat KO mice were given intraperitoneal injections of DEN (25 mg/kg body wt). Eight months later, Lrat KO mice showed significantly less liver tumor development compared with WT mice, characterized by less liver tumor incidence and smaller tumor size. Two days after DEN injection, lower serum levels of alanine aminotransferase and decreased hepatic levels of cyclin D1 were observed in Lrat KO mice. Lrat KO mice also exhibited increased levels of retinoic acid-responsive genes, including p21, lower levels of cytochrome P450 enzymes required for DEN bioactivation and higher levels of the DNA repair enzyme O(6)-methylguanine-DNA methyltransferase (MGMT), both before and after DEN treatment. Our results indicate that Lrat KO mice are less susceptible to DEN-induced hepatocarcinogenesis due to increased retinoid signaling and higher expression of p21, which is accompanied by altered hepatic levels of DEN-activating enzymes and MGMT in Lrat KO mice also contribute to decreased cancer initiation and suppressed liver tumor development.

The role of S1PR2 in bile acid-induced cholangiocyte proliferation and cholestasis-induced liver injury in mice

PubMed Central

Wang, Yongqing; Aoki, Hiroaki; Yang, Jing; Peng, Kesong; Liu, Runping; Li, Xiaojiaoyang; Qiang, Xiaoyan; Sun, Lixin; Gurley, Emily C; Lai, Guanhua; Zhang, Luyong; Liang, Guang; Nagahashi, Masayuki; Takabe, Kazuaki; Pandak, William M; Hylemon, Phillip B.; Zhou, Huiping

2017-01-01

Bile duct obstruction is a potent stimulus for cholangiocyte proliferation, especially for large cholangiocytes. Our previous studies reported that conjugated bile acids (CBAs) activate the AKT and ERK1/2 signaling pathways via the sphingosine 1-phosphate receptor 2 (S1PR2) in hepatocytes and cholangiocarcinoma cells. It also has been reported that taurocholate (TCA) promotes large cholangiocyte proliferation and protects cholangiocytes from bile duct ligation (BDL)-induced apoptosis. However, the role of S1PR2 in bile acid-mediated cholangiocyte proliferation and cholestatic liver injury has not been elucidated. Here we report that S1PR2 is the predominant S1PR expressed in cholangiocytes. Both TCA- and S1P-induced activation of ERK1/2 and AKT were inhibited by JTE-013, a specific antagonist of S1PR2, in cholangiocytes. In addition, TCA- and S1P-induced cell proliferation and migration were inhibited by JTE-013 and a specific shRNA of S1PR2 as well as chemical inhibitors of ERK1/2 and AKT in mouse cholangiocytes. In BDL mice, the expression of S1PR2 was upregulated in whole liver and cholangiocytes. S1PR2 deficiency significantly reduced BDL-induced cholangiocyte proliferation and cholestatic injury as indicated by significant reduction of inflammation and liver fibrosis in S1PR2−/− mice. Treatment of BDL mice with JTE-013 significantly reduced total bile acid levels in the serum and cholestatic liver injury. This study suggests that the CBA-induced activation of S1PR2-mediated signaling pathways plays a critical role in obstructive cholestasis and may represent a novel therapeutic target for cholestatic liver diseases. PMID:28120434

Anti-fibrotic potential of human umbilical cord mononuclear cells and mouse bone marrow cells in CCl4- induced liver fibrosis in mice.

PubMed

Elmahdy, Nageh Ahmed; Sokar, Samia Salem; Salem, Mohamed Labib; Sarhan, Naglaa Ibrahim; Abou-Elela, Sherin Hamed

2017-05-01

Liver fibrosis is the consequence of hepatocyte injury that leads to the activation of hepatic stellate cells (HSC). The treatment of choice is Liver transplantation; however, it has many problems such as surgery-related complications, immunological rejection and high costs associated with the procedure. Stem cell-based therapy would be a potential alternative, so the aim of this study is to investigate the therapeutic potential of human umbilical cord mononuclear cells (MNC) and mouse bone marrow cells (BMC) against carbon tetrachloride (CCl 4 ) induced liver fibrosis in mice and compare it with that of silymarin. In the present study, male albino mice (N=60) were divided into six groups (10 mice each), the first group served as the normal control group while the remaining five groups were rendered fibrotic by intraperitoneal injections of CCl 4 and being left for 6 weeks to develop hepatic fibrosis. Thereafter, the mice were divided into CCl 4 group, CCl 4 group receiving MNC or BMC or silymarin or MNC and silymarin combination. After the specified treatment period, animals were then euthanized, blood and tissue samples were collected for measurement of alanine aminotransferase(ALT), aspartate aminotransferase(AST), malondialdehyde(MDA), reduced glutathione(GSH), collagen, Laminin, transforming growth factor β1(TGFβ1), tumor necrosis factor alpha(TNFα). MNC, BMC, and the combination therapy showed a significant decrease in ALT, AST, MDA, collagen, Laminin, TGFβ1, and TNFα and a significant increase in GSH. The data displayed a similar regression of fibrosis with the histological and immunohistological parameters. In conclusion, MNC, BMC and the combination therapy showed a potential therapeutic effect against liver fibrosis via reducing oxidative stress, inflammatory mediators, and fibrogenic markers. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Isoliquiritigenin protects against sepsis-induced lung and liver injury by reducing inflammatory responses.

PubMed

Chen, Xiong; Cai, Xueding; Le, Rongrong; Zhang, Man; Gu, Xuemei; Shen, Feixia; Hong, Guangliang; Chen, Zimiao

2018-02-05

Sepsis, one of the most fatal diseases worldwide, often leads to multiple organ failure, mainly due to uncontrolled inflammatory responses. Despite accumulating knowledge obtained in recent years, effective drugs to treat sepsis in the clinic are still urgently needed. Isoliquiritigenin (ISL), a chalcone compound, has been reported to exert anti-inflammatory properties. However, little is known about the effects of ISL on sepsis and its related complications. In this study, we investigated the potential protective effects of ISL on lipopolysaccharide (LPS)-induced injuries and identified the mechanisms underlying these effects. ISL inhibited inflammatory cytokine expression in mouse primary peritoneal macrophages (MPMs) exposed to LPS. In an acute lung injury (ALI) mouse model, ISL prevented LPS-induced structural damage and inflammatory cell infiltration. Additionally, pretreatment with ISL attenuated sepsis-induced lung and liver injury, accompanied by a reduction in inflammatory responses. Moreover, these protective effects were mediated by the nuclear factor kappa B (NF-κB) pathway-mediated inhibition of inflammatory responses in vitro and in vivo. Our study suggests that ISL may be a potential therapeutic agent for sepsis-induced injuries. Copyright © 2017. Published by Elsevier Inc.

Silymarin attenuated hepatic steatosis through regulation of lipid metabolism and oxidative stress in a mouse model of nonalcoholic fatty liver disease (NAFLD).

PubMed

Ni, Xunjun; Wang, Haiyan

2016-01-01

Silymarin, which derived from the milk thistle plant (silybum marianum), has been used for centuries as a natural remedy for diseases of the liver and biliary tract. Considering the therapeutic potential to liver disease, we tested efficacy of silymarin on hepatic steatosis with a high fat diet (HFD)-induced mouse model of non-alcoholic fatty liver disease (NAFLD), and investigated possible effects on lipid metabolic pathways. In our study, silymarin could attenuate the hepatic steatosis, which was proved by both Oil Red O staining and hepatic triglyceride (TG) level determination. Furthermore, compared with INT-747, a potent and selective FXR agonist, silymarin could preserve plasmatic high-density lipoprotein cholesterol (HDL-C) to a higher level and low-density lipoprotein cholesterol (LDL-C) to a lower level, which benefited more to the circulation system. Through real-time PCR analysis, we clarified a vital protective role of silymarin in mRNA regulation of genes involved in lipid metabolism and oxidative stress. It was also shown that silymarin had no effects on body weight, food intake, and liver transaminase. Taken together, silymarin could attenuate hepatic steatosis in a mouse model of NAFLD through regulation of lipid metabolism and oxidative stress, and benefit to the circulation system. All these findings shed new light on NAFLD treatment.

STAT3 activation in monocytes accelerates liver cancer progression.

PubMed

Wu, Wen-Yong; Li, Jun; Wu, Zheng-Sheng; Zhang, Chang-Le; Meng, Xiang-Ling

2011-12-05

Signal transducer and activator of transcription 3 (STAT3) is an important transcription factor ubiquitously expressed in different cell types. STAT3 plays an essential role in cell survival, proliferation, and differentiation. Aberrantly hyper-activated STAT3 signaling in cancer cells and in the tumor microenvironment has been detected in a wide variety of human cancers and is considered an important factor for cancer initiation, development, and progression. However, the role of STAT3 activation in monocytes in the development of HCC has not been well understood. Immunohistochemical analysis of phosphorylated STAT3 was performed on tissue microarray from HCC patients. Using a co-culture system in vivo, HCC cell growth was determined by the MTT assay. In vivo experiments were conducted with mice given diethylinitrosamine (DEN), which induces HCC was used to investigate the role of STAT3 expression in monocytes on tumor growth. Real-time PCR was used to determine the expression of cell proliferation and cell arrest associated genes in the tumor and nontumor tissue from liver. Phosphorylated STAT3 was found in human hepatocellular carcinoma tissue samples and was expressed in tumor cells and also in monocytes. Phosphorylated STAT3 expression in monocyte was significantly correlated to advanced clinical stage of HCC and a poor prognosis. Using a co-culture system in vivo, monocytes promoted HCC cell growth via the IL-6/STAT3 signaling pathway. The STAT3 inhibitor, NSC 74859, significantly suppressed tumor growth in vivo in mice with diethylinitrosamine (DEN)-induced HCC. In this animal model, blockade of STAT3 with NSC 74859 induced tumor cell apoptosis, while inhibiting both tumor cells and monocytes proliferation. Furthermore, NSC 74859 treatment suppressed cancer associated inflammation in DEN-induce HCC. Our data suggest constitutively activated STAT3 monocytes promote liver tumorigenesis in clinical patients and animal experiments. Thus, STAT3 in tumor

Dietary broccoli protects against fatty liver development but not against progression of liver cancer in mice pretreated with diethylnitrosamine

PubMed Central

Chen, Yung-Ju; Myracle, Angela D.; Wallig, Matthew A.; Jeffery, Elizabeth H.

2016-01-01

Western-style high fat, high sugar diets are associated with non-alcoholic fatty liver disease (NAFLD) and increased liver cancer risk. Sulforaphane from broccoli may protect against these. Previously we initiated broccoli feeding to mice prior to exposure to the hepatocarcinogen diethylnitrosamine (DEN), and saw protection against NAFLD and liver cancer. Here we administered DEN to unweaned mice, initiating broccoli feeding two weeks later, to determine if broccoli protects against cancer progression. Specifically, male 15-day-old C57BL/6J mice were given DEN and placed on a Western or Western+10%Broccoli diet from the age of 4 weeks through 7 months. Dietary broccoli decreased hepatic triacylglycerols, NAFLD, liver damage and tumour necrosis factor by month 5 without changing body weight or relative liver weight, but did not slow carcinogenesis, seen in 100% of mice. We conclude that broccoli, a good source of sulforaphane, slows progression of hepatic lipidosis, but not tumourigenesis in this robust model. PMID:27672403

Inhibition of tumor necrosis factor alpha reduces the outgrowth of hepatic micrometastasis of colorectal tumors in a mouse model of liver ischemia-reperfusion injury.

PubMed

Jiao, Shu-Fan; Sun, Kai; Chen, Xiao-Jing; Zhao, Xue; Cai, Ning; Liu, Yan-Jun; Xu, Long-Mei; Kong, Xian-Ming; Wei, Li-Xin

2014-01-08

Patients with colorectal cancer (CRC) often develop liver metastases, in which case surgery is considered the only potentially curative treatment option. However, liver surgery is associated with a risk of ischemia-reperfusion (IR) injury, which is thought to promote the growth of colorectal liver metastases. The influence of IR-induced tumor necrosis factor alpha (TNF-α) elevation in the process still is unknown. To investigate the role of TNF-α in the growth of pre-existing micrometastases in the liver following IR, we used a mouse model of colorectal liver metastases. In this model, mice received IR treatment seven days after intrasplenic injections of colorectal CT26 cells. Prior to IR treatment, either TNF-α blocker Enbrel or low-dose TNF-α, which could inhibit IR-induced TNF-α elevation, was administered by intraperitoneal injection. Hepatic IR treatment significantly promoted CT26 tumor growth in the liver, but either Enbrel or low-dose TNF-α pretreatment reversed this trend. Further studies showed that the CT26 + IR group prominently increased the levels of ALT and AST, liver necrosis, inflammatory infiltration and the expressions of hepatic IL-6, MMP9 and E-selectin compared to those of CT26 group. Inhibition of TNF-α elevation remarkably attenuated the increases of these liver inflammatory damage indicators and tumor-promoting factors. These findings suggested that inhibition of TNF-α elevation delayed the IR-enhanced outgrowth of colorectal liver metastases by reducing IR-induced inflammatory damage and the formation of tumor-promoting microenvironments. Both Enbrel and low-dose TNF-α represented the potential therapeutic approaches for the protection of colorectal liver metastatic patients against IR injury-induced growth of liver micrometastases foci.

Inhibition of tumor necrosis factor alpha reduces the outgrowth of hepatic micrometastasis of colorectal tumors in a mouse model of liver ischemia-reperfusion injury

PubMed Central

2014-01-01

Background Patients with colorectal cancer (CRC) often develop liver metastases, in which case surgery is considered the only potentially curative treatment option. However, liver surgery is associated with a risk of ischemia-reperfusion (IR) injury, which is thought to promote the growth of colorectal liver metastases. The influence of IR-induced tumor necrosis factor alpha (TNF-α) elevation in the process still is unknown. To investigate the role of TNF-α in the growth of pre-existing micrometastases in the liver following IR, we used a mouse model of colorectal liver metastases. In this model, mice received IR treatment seven days after intrasplenic injections of colorectal CT26 cells. Prior to IR treatment, either TNF-α blocker Enbrel or low-dose TNF-α, which could inhibit IR-induced TNF-α elevation, was administered by intraperitoneal injection. Results Hepatic IR treatment significantly promoted CT26 tumor growth in the liver, but either Enbrel or low-dose TNF-α pretreatment reversed this trend. Further studies showed that the CT26 + IR group prominently increased the levels of ALT and AST, liver necrosis, inflammatory infiltration and the expressions of hepatic IL-6, MMP9 and E-selectin compared to those of CT26 group. Inhibition of TNF-α elevation remarkably attenuated the increases of these liver inflammatory damage indicators and tumor-promoting factors. Conclusion These findings suggested that inhibition of TNF-α elevation delayed the IR-enhanced outgrowth of colorectal liver metastases by reducing IR-induced inflammatory damage and the formation of tumor-promoting microenvironments. Both Enbrel and low-dose TNF-α represented the potential therapeutic approaches for the protection of colorectal liver metastatic patients against IR injury-induced growth of liver micrometastases foci. PMID:24397824

Advanced Method for Isolation of Mouse Hepatocytes, Liver Sinusoidal Endothelial Cells, and Kupffer Cells.

PubMed

Liu, Jia; Huang, Xuan; Werner, Melanie; Broering, Ruth; Yang, Dongliang; Lu, Mengji

2017-01-01

Separation of pure cell populations from the liver is a prerequisite to study the role of hepatic parenchymal and non-parenchymal cells in liver physiology, pathophysiology, and immunology. Traditional methods for hepatic cell separation usually purify only single cell types from liver specimens. Here, we describe an efficient method that can simultaneously purify populations of hepatocytes (HCs), liver sinusoidal endothelial cells (LSECs), and Kupffer cells (KCs) from a single mouse liver specimen. A liberase-based perfusion technique in combination with a low-speed centrifugation and magnetic-activated cell sorting (MACS) led to the isolation and purification of HCs, KCs, and LSECs with high yields and purity.

Risk assessment of silica nanoparticles on liver injury in metabolic syndrome mice induced by fructose.

PubMed

Li, Jianmei; He, Xiwei; Yang, Yang; Li, Mei; Xu, Chenke; Yu, Rong

2018-07-01

This study aims to assess the effects and the mechanisms of silica nanoparticles (SiNPs) on hepatotoxicity in both normal and metabolic syndrome mouse models induced by fructose. Here, we found that SiNPs exposure lead to improved insulin resistance in metabolic syndrome mice, but markedly worsened hepatic ballooning, inflammation infiltration, and fibrosis. Moreover, SiNPs exposure aggravated liver injury in metabolic syndrome mice by causing serious DNA damage. Following SiNPs exposure, liver superoxide dismutase and catalase activities in metabolic syndrome mice were stimulated, which is accompanied by significantly increased malondialdehyde and 8-hydroxy-2-deoxyguanosine levels as compared to normal mice. Scanning electron microscope (SEM) revealed that SiNPs were more readily deposited in the liver mitochondria of metabolic syndrome mice, resulting in more severe mitochondrial injury as compared to normal mice. We speculated that SiNPs-induced mitochondrial injury might be the cause of hepatic oxidative stress, which further lead to a series of liver lesions as observed in mice following SiNPs exposure. Based on these results, it is likely that SiNPs will increase the risk and severity of liver disease in individuals with metabolic syndrome. Therefore, SiNPs should be used cautiously in food additives and clinical settings. Copyright © 2018 Elsevier B.V. All rights reserved.

CD8 T-cell-mediated protection against liver-stage malaria: lessons from a mouse model

PubMed Central

Van Braeckel-Budimir, Natalija; Harty, John T.

2014-01-01

Malaria is a major global health problem, with severe mortality in children living in sub-Saharan Africa, and there is currently no licensed, effective vaccine. However, vaccine-induced protection from Plasmodium infection, the causative agent of malaria, was established for humans in small clinical trials and for rodents in the 1960s. Soon after, a critical role for memory CD8 T cells in vaccine-induced protection against Plasmodium liver-stage infection was established in rodent models and is assumed to apply to humans. However, these seminal early studies have led to only modest advances over the ensuing years in our understanding the basic features of memory CD8 T cells required for protection against liver-stage Plasmodium infection, an issue which has likely impeded the development of effective vaccines for humans. Given the ethical and practical limitations in gaining mechanistic insight from human vaccine and challenge studies, animal models still have an important role in dissecting the basic parameters underlying memory CD8 T-cell immunity to Plasmodium. Here, we will highlight recent data from our own work in the mouse model of Plasmodium infection that identify quantitative and qualitative features of protective memory CD8 T-cell responses. Finally, these lessons will be discussed in the context of recent findings from clinical trials of vaccine-induced protection in controlled human challenge models. PMID:24936199

Bifidobacterium breve B-3 exerts metabolic syndrome-suppressing effects in the liver of diet-induced obese mice: a DNA microarray analysis.

PubMed

Kondo, S; Kamei, A; Xiao, J Z; Iwatsuki, K; Abe, K

2013-09-01

We previously reported that supplementation with Bifidobacterium breve B-3 reduced body weight gain and accumulation of visceral fat in a dose-dependent manner, and improved serum levels of total cholesterol, glucose and insulin in a mouse model of diet-induced obesity. In this study, we investigated the expression of genes in the liver using DNA microarray analysis and q-PCR to reveal the mechanism of these anti-obesity effects in this mouse model. Administration of B. breve B-3 led to regulated gene expression of pathways involved in lipid metabolism and response to stress. The results indicate that these regulations in the liver are related to the anti-metabolic syndrome effects of B. breve B-3.

Withaferin-A Reduces Acetaminophen-Induced Liver Injury in Mice.

PubMed

Jadeja, Ravirajsinh N; Urrunaga, Nathalie H; Dash, Suchismita; Khurana, Sandeep; Saxena, Neeraj Kumar

2015-09-01

Withaferin-A (WA) has anti-oxidant activities however, its therapeutic potential in acetaminophen (APAP) hepatotoxicity is unknown. We performed a proof-of-concept study to assess the therapeutic potential of WA in a mouse model that mimics APAP-induced liver injury (AILI) in humans. Overnight fasted C57BL/6NTac (5-6 wk. old) male mice received 200 mg/kg APAP intraperitoneally (i.p.). After 1 h mice were treated with 40 mg/kg WA or vehicle i.p., and euthanized 4 and 16 h later; their livers were harvested and serum collected for analysis. At 4 h, compared to vehicle-treated mice, WA-treated mice had reduced serum ALT levels, hepatocyte necrosis and intrahepatic hemorrhage. All APAP-treated mice had reduced hepatic glutathione (GSH) levels however, reduction in GSH was lower in WA-treated when compared to vehicle-treated mice. Compared to vehicle-treated mice, livers from WA-treated mice had reduced APAP-induced JNK activation, mitochondrial Bax translocation, and nitrotyrosine generation. Compared to vehicle-treated mice, WA-treated mice had increased hepatic up-regulation of Nrf2, Gclc and Nqo1, and down-regulation of Il-6 and Il-1β. The hepatoprotective effect of WA persisted at 16 h. Compared to vehicle-treated mice, WA-treated mice had reduced hepatocyte necrosis and hepatic expression of Il-6, Tnf-α and Il-1β, increased hepatic Gclc and Nqo1 expression and GSH levels, and reduced lipid peroxidation. Finally, in AML12 hepatocytes, WA reduced H₂O₂-induced oxidative stress and necrosis by preventing GSH depletion. Collectively, these data show mechanisms whereby WA reduces necrotic hepatocyte injury, and demonstrate that WA has therapeutic potential in AILI. Copyright © 2015 Elsevier Inc. All rights reserved.

Preventive effects of indole-3-carbinol against alcohol-induced liver injury in mice via antioxidant, anti-inflammatory, and anti-apoptotic mechanisms: Role of gut-liver-adipose tissue axis.

PubMed

Choi, Youngshim; Abdelmegeed, Mohamed A; Song, Byoung-Joon

2018-05-01

Indole-3-carbinol (I3C), found in Brassica family vegetables, exhibits antioxidant, anti-inflammatory, and anti-cancerous properties. Here, we aimed to evaluate the preventive effects of I3C against ethanol (EtOH)-induced liver injury and study the protective mechanism(s) by using the well-established chronic-plus-binge alcohol exposure model. The preventive effects of I3C were evaluated by conducting various histological, biochemical, and real-time PCR analyses in mouse liver, adipose tissue, and colon, since functional alterations of adipose tissue and intestine can also participate in promoting EtOH-induced liver damage. Daily treatment with I3C alleviated EtOH-induced liver injury and hepatocyte apoptosis, but not steatosis, by attenuating elevated oxidative stress, as evidenced by the decreased levels of hepatic lipid peroxidation, hydrogen peroxide, CYP2E1, NADPH-oxidase, and protein acetylation with maintenance of mitochondrial complex I, II, and III protein levels and activities. I3C also restored the hepatic antioxidant capacity by preventing EtOH-induced suppression of glutathione contents and mitochondrial aldehyde dehydrogenase-2 activity. I3C preventive effects were also achieved by attenuating the increased levels of hepatic proinflammatory cytokines, including IL1β, and neutrophil infiltration. I3C also attenuated EtOH-induced gut leakiness with decreased serum endotoxin levels through preventing EtOH-induced oxidative stress, apoptosis of enterocytes, and alteration of tight junction protein claudin-1. Furthermore, I3C alleviated adipose tissue inflammation and decreased free fatty acid release. Collectively, I3C prevented EtOH-induced liver injury via attenuating the damaging effect of ethanol on the gut-liver-adipose tissue axis. Therefore, I3C may also have a high potential for translational research in treating or preventing other types of hepatic injury associated with oxidative stress and inflammation. Copyright © 2017 Elsevier Inc. All

Bcl-2 does not inhibit the permeability transition pore in mouse liver mitochondria.

PubMed

Yang, J C; Kahn, A; Cortopassi, G

2000-10-26

. Therefore, while we observe a strong inhibition of Fas-dependent apoptosis by Bcl-2 overexpression in mouse liver, we observe no effect of Bcl-2 overexpression on either the rate or extent of mitochondrial PTP, or upon the release of cytochrome c from mitochondria in which the PTP has been induced. The simplest explanation of these results is that Bcl-2 inhibits neither PTP nor PTP-dependent release of cytochrome c, however, other possibilities are discussed.

MicroRNA-mediated Th2 bias in methimazole-induced acute liver injury in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uematsu, Yasuaki, E-mail: yasuaki-uematsu@ds-pharm

MicroRNA (miRNA) is a class of small non-coding RNAs containing approximately 20 nucleotides that negatively regulate target gene expression. Little is known about the role of individual miRNAs and their targets in immune- and inflammation-related responses in drug-induced liver injury. In the present study, involvement of miRNAs in the T helper (Th) 2-type immune response was investigated using a methimazole (MTZ)-induced liver injury mouse model. Co-administration of L-buthionine-S,R-sulfoximine and MTZ induced acute hepatocellular necrosis and elevated plasma levels of alanine aminotransferase (ALT) from 4 h onward in female Balb/c mice. The hepatic mRNA expression of Th2 promotive factors was significantlymore » increased concomitantly with plasma ALT levels. In contrast, the hepatic mRNA expression of Th2 suppressive factors was significantly decreased during the early phase of liver injury. Comprehensive profiling of hepatic miRNA expression was analyzed before the onset of MTZ-induced liver injury. Using in silico prediction of miRNAs that possibly regulate Th2-related genes and subsequent quantification, we identified up-regulation of expression of miR-29b-1-5p and miR-449a-5p. Among targets of these miRNAs, down-regulation of Th2 suppressive transcription factors, such as SRY-related HMG-box 4 (SOX4) and lymphoid enhancer factor-1 (LEF1), were observed from the early phase of liver injury. In conclusion, negative regulation of the expression of SOX4 by miR-29b-1-5p and that of LEF1 by miR-449a-5p is suggested to play an important role in the development of Th2 bias in MTZ-induced liver injury. - Highlights: • Methimazole induced hepatic Th2 bias in the pathogenesis of liver injury in mice. • Rapid down-regulation of SOX4 and LEF1 may initiate and/or maintain hepatic Th2 bias. • Negative regulation of SOX4 by miR-29b-1-5p and LEF1 by miR-449a-5p was suggested.« less

Autophagy in alcohol-induced liver diseases

PubMed Central

Dolganiuc, Angela; Thomes, Paul G.; Ding, Wen-Xing; Lemasters, John J.; Donohue, Terrence M.

2013-01-01

Alcohol is the most abused substance worldwide and a significant source of liver injury; the mechanisms of alcohol-induced liver disease are not fully understood. Significant cellular toxicity and impairment of protein synthesis and degradation occur in alcohol-exposed liver cells, along with changes in energy balance and modified responses to pathogens. Autophagy is the process of cellular catabolism through the lysosomal-dependent machinery, which maintains a balance among protein synthesis, degradation, and recycling of self. Autophagy is part of normal homeostasis and it can be triggered by multiple factors that threaten cell integrity including starvation, toxins, or pathogens. Multiple factors regulate autophagy; survival and preservation of cellular integrity at the expense of inadequately-folded proteins and damaged high energy-generating intracellular organelles are prominent targets of autophagy in pathologic conditions. Coincidentally, inadequately-folded proteins accumulate and high energy-generating intracellular organelles, such as mitochondria, are damaged by alcohol abuse; these alcohol-induced pathological findings prompted investigation of the role of autophagy in the pathogenesis of alcohol-induced liver damage. Our review summarizes the current knowledge about the role and implications of autophagy in alcohol-induced liver disease. PMID:22551004

Different mutation patterns of mitochondrial DNA displacement-loop in hepatocellular carcinomas induced by N-nitrosodiethylamine and a choline-deficient l-amino acid-defined diet in rats.

PubMed

Onishi, Mariko; Sokuza, Yui; Nishikawa, Tomoki; Mori, Chiharu; Uwataki, Kimiko; Honoki, Kanya; Tsujiuchi, Toshifumi

2007-10-12

Mutations of the mitochondria DNA (mtDNA) displacement loop (D-loop) were investigated to clarify different changes of exogenous and endogenous liver carcinogenesis in rats. We induced hepatocellular carcinomas (HCCs) in rats with N-nitrosodiethylamine (DEN) and a choline-deficient l-amino acid-defined (CDAA) diet. DNAs were extracted from 10 HCCs induced by DEN and 10 HCCs induced by the CDAA diet. To identify mutations in mtDNA D-loop, polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis, followed by nucleotide sequencing, was performed. Mutations were detected in 5 out of 10 HCCs (50%) induced by DEN. Four out of 5 mutations were G/C to A/T transitions at positions 15707, 15717, 15930, and 16087, and one T/A to C/G transition at position 15559. By contrast, no mutations were found in 10 HCCs induced by the CDAA diet. These results demonstrated that mutations in mtDNA D-loop occur in rat HCCs induced by DEN but not by the CDAA diet, suggesting that mtDNA D-loop is a target of exogenous liver carcinogenesis in rats.

Anticancer activity of Cynodon dactylon L. root extract against diethyl nitrosamine induced hepatic carcinoma

PubMed Central

Kowsalya, R.; Kaliaperumal, Jagatheesh; Vaishnavi, M.; Namasivayam, Elangovan

2015-01-01

Background: Hepatocellular carcinoma is one of the most common cancers and a lethal disease. In view of the limited treatment and a grave prognosis of liver cancer, preventive control has been emphasized. Materials and Methods: The methanolic extract of roots of Cynodon dactylon was screened for its hepato-protective activity in diethyl nitrosamine (DEN) induced liver cancer in Swiss albino mice. The plant extract at a dose of 50 mg/kg was administered orally once a week, up to 30 days after DEN administration. The animals were sacrificed; blood sample and liver tissue were collected and used for enzyme assay such as, asparatate amino transferase (AST), alanine aminotransferase (ALT), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST). The liver marker enzymes AST and ALT produced significant results in the protective action. Results: The antioxidant enzyme assay results concerning the improved activity of GPx, GST and CAT. These results concluded that enhanced levels of antioxidant enzyme and reduced amount of serum amino transaminase, which are suggested to be the major mechanisms of C. dactylon root extract in protecting the mice from hepatocarcinoma induced by DEN. These biochemical observations were supplemented by histopathological examination of liver sections. Conclusion: The methanolic extract of C. dactylon possesses significant anticancer properties PMID:25992348

Anticancer activity of Cynodon dactylon L. root extract against diethyl nitrosamine induced hepatic carcinoma.

PubMed

Kowsalya, R; Kaliaperumal, Jagatheesh; Vaishnavi, M; Namasivayam, Elangovan

2015-01-01

Hepatocellular carcinoma is one of the most common cancers and a lethal disease. In view of the limited treatment and a grave prognosis of liver cancer, preventive control has been emphasized. The methanolic extract of roots of Cynodon dactylon was screened for its hepato-protective activity in diethyl nitrosamine (DEN) induced liver cancer in Swiss albino mice. The plant extract at a dose of 50 mg/kg was administered orally once a week, up to 30 days after DEN administration. The animals were sacrificed; blood sample and liver tissue were collected and used for enzyme assay such as, asparatate amino transferase (AST), alanine aminotransferase (ALT), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST). The liver marker enzymes AST and ALT produced significant results in the protective action. The antioxidant enzyme assay results concerning the improved activity of GPx, GST and CAT. These results concluded that enhanced levels of antioxidant enzyme and reduced amount of serum amino transaminase, which are suggested to be the major mechanisms of C. dactylon root extract in protecting the mice from hepatocarcinoma induced by DEN. These biochemical observations were supplemented by histopathological examination of liver sections. The methanolic extract of C. dactylon possesses significant anticancer properties.

Total Flavonoid Extract from Abelmoschus manihot (L.) Medic Flowers Attenuates d-Galactose-Induced Oxidative Stress in Mouse Liver Through the Nrf2 Pathway.

PubMed

Qiu, Yan; Ai, Peng-Fei; Song, Jian-Jun; Liu, Chang; Li, Zhi-Wei

2017-06-01

Abelmoschus manihot (L.) Medic is an edible hibiscus that is rich in flavonoids, and its use as Chinese herbal medicine for the treatment of diseases and health maintenance dates back to ancient times. The chemical compositions of total flavonoid of A. manihot (L.) Medic flower extract (TFAE) were identified and determined by high performance liquid chromatography (HPLC). The effects of TFAE on antioxidative activities in a d-galactose (d-gal)-induced mouse model and Nrf2-mediated antioxidant responses were evaluated. Male Kunming mice were randomly divided into normal control group, d-gal aging model group, d-gal+ascorbic acid group that served as a positive control, and d-gal+TFAE (40, 80, and 160 mg TFAE/kg) group. After 42 days, the antioxidant effects of these treatments were determined by biochemical studies, Western blotting, quantitative real-time polymerase chain reaction, and histological analysis. The results showed that the groups administered TFAE exhibited significant elevation in liver activities of antioxidant enzymes, including catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC), and decreased malondialdehyde (MDA) production in a dose-dependent manner compared with the d-gal-induced model group. Expression of Nrf2 and its target antioxidants (HO-1 and NQO1) was manifestly increased by TFAE treatment. TFAE also increased mRNA expression of GPx, SOD, and CAT and decreased tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β). Furthermore, the microstructure of livers in TFAE-administered mice was obviously improved as compared with the d-gal model group. These results suggest that TFAE protects mice against d-gal-induced oxidative stress, and the effect is related to the activation of Nrf2 signaling.

The DenA/DEN1 Interacting Phosphatase DipA Controls Septa Positioning and Phosphorylation-Dependent Stability of Cytoplasmatic DenA/DEN1 during Fungal Development

PubMed Central

Schinke, Josua; Kolog Gulko, Miriam; Christmann, Martin; Valerius, Oliver; Stumpf, Sina Kristin; Stirz, Margarita; Braus, Gerhard H.

2016-01-01

DenA/DEN1 and the COP9 signalosome (CSN) represent two deneddylases which remove the ubiquitin-like Nedd8 from modified target proteins and are required for distinct fungal developmental programmes. The cellular DenA/DEN1 population is divided into a nuclear and a cytoplasmatic subpopulation which is especially enriched at septa. DenA/DEN1 stability control mechanisms are different for the two cellular subpopulations and depend on different physical interacting proteins and the C-terminal DenA/DEN1 phosphorylation pattern. Nuclear DenA/DEN1 is destabilized during fungal development by five of the eight CSN subunits which target nuclear DenA/DEN1 for degradation. DenA/DEN1 becomes stabilized as a phosphoprotein at S243/S245 during vegetative growth, which is necessary to support further asexual development. After the initial phase of development, the newly identified cytoplasmatic DenA/DEN1 interacting phosphatase DipA and an additional developmental specific C-terminal phosphorylation site at serine S253 destabilize DenA/DEN1. Outside of the nucleus, DipA is co-transported with DenA/DEN1 in the cytoplasm between septa and nuclei. Deletion of dipA resulted in increased DenA/DEN1 stability in a strain which is unresponsive to illumination. The mutant strain is dysregulated in cytokinesis and impaired in asexual development. Our results suggest a dual phosphorylation-dependent DenA/DEN1 stability control with stabilizing and destabilizing modifications and physical interaction partner proteins which function as control points in the nucleus and the cytoplasm. PMID:27010942

Mesenchymal Stem Cell/Red Blood Cell-Inspired Nanoparticle Therapy in Mice with Carbon Tetrachloride-Induced Acute Liver Failure.

PubMed

Liang, Hongxia; Huang, Ke; Su, Teng; Li, Zhenhua; Hu, Shiqi; Dinh, Phuong-Uyen; Wrona, Emily A; Shao, Chen; Qiao, Li; Vandergriff, Adam C; Hensley, M Taylor; Cores, Jhon; Allen, Tyler; Zhang, Hongyu; Zeng, Qinglei; Xing, Jiyuan; Freytes, Donald O; Shen, Deliang; Yu, Zujiang; Cheng, Ke

2018-06-26

Acute liver failure is a critical condition characterized by global hepatocyte death and often time needs a liver transplantation. Such treatment is largely limited by donor organ shortage. Stem cell therapy offers a promising option to patients with acute liver failure. Yet, therapeutic efficacy and feasibility are hindered by delivery route and storage instability of live cell products. We fabricated a nanoparticle that carries the beneficial regenerative factors from mesenchymal stem cells and further coated it with the membranes of red blood cells to increase blood stability. Unlike uncoated nanoparticles, these particles promote liver cell proliferation in vitro and have lower internalization by macrophage cells. After intravenous delivery, these artificial stem cell analogs are able to remain in the liver and mitigate carbon tetrachloride-induced liver failure in a mouse model, as gauged by histology and liver function test. Our technology provides an innovative and off-the-shelf strategy to treat liver failure.

Mouse genotypes drive the liver and adrenal gland clocks

NASA Astrophysics Data System (ADS)

Košir, Rok; Prosenc Zmrzljak, Uršula; Korenčič, Anja; Juvan, Peter; Ačimovič, Jure; Rozman, Damjana

2016-08-01

Circadian rhythms regulate a plethora of physiological processes. Perturbations of the rhythm can result in pathologies which are frequently studied in inbred mouse strains. We show that the genotype of mouse lines defines the circadian gene expression patterns. Expression of majority of core clock and output metabolic genes are phase delayed in the C56BL/6J line compared to 129S2 in the adrenal glands and the liver. Circadian amplitudes are generally higher in the 129S2 line. Experiments in dark - dark (DD) and light - dark conditions (LD), exome sequencing and data mining proposed that mouse lines differ in single nucleotide variants in the binding regions of clock related transcription factors in open chromatin regions. A possible mechanisms of differential circadian expression could be the entrainment and transmission of the light signal to peripheral organs. This is supported by the genotype effect in adrenal glands that is largest under LD, and by the high number of single nucleotide variants in the Receptor, Kinase and G-protein coupled receptor Panther molecular function categories. Different phenotypes of the two mouse lines and changed amino acid sequence of the Period 2 protein possibly contribute further to the observed differences in circadian gene expression.

FINE STRUCTURE OF CELLS ISOLATED FROM ADULT MOUSE LIVER

PubMed Central

Berry, M. N.; Simpson, F. O.

1962-01-01

Suspensions of isolated cells in various media were prepared from mouse liver which had been perfused via the portal vein with a buffered medium containing 0.40 M sucrose, and the cells were fixed with osmium tetroxide. Their fine structure was compared with that of cells from perfused and unperfused intact liver. Perfusion brought about some separation of the cells with little or no damage to cell membranes. When cells were dispersed in 0.40 M sucrose medium the plasma membranes partially broke down, and this disintegration was increased by transfer of the cells to media of lower osmolarity. This is presumed to account for the loss of permeability barriers which occurs in isolated liver cells. The mitochondria in cells of perfused liver and in isolated cells remained elongated, but the layers of many mitochondrial cristae became separated by clear spaces. When cells were transferred to a medium containing 0.20 M sucrose, the mitochondria swelled and became spherical, often with displacement of the swollen cristae to the periphery. In a medium containing 0.06 M sucrose and 0.08 M potassium chloride the outer chamber of many mitochondria became swollen with displacement of the mitochondrial body to one side to give a crescent-shaped appearance. These changes in mitochondrial morphology are discussed in relation to the metabolic activity of isolated liver cells. PMID:19866610

Gamma-glutamylcysteinylethyl ester attenuates progression of carbon tetrachloride-induced acute liver injury in mice.

PubMed

Nishida, K; Ohta, Y; Ishiguro, I

1998-02-20

We examined the effect of gamma-glutamylcysteinylethyl ester (gamma-GCE), which is readily transported into hepatocytes and increases hepatocellular reduced glutathione (GSH) levels, on the progression of carbon tetrachloride (CCl4)-induced liver injury in mice in comparison with that of GSH. Administration of more than 160 micromol/kg of gamma-GCE, but not GSH, to mice at 3 h after intraperitoneal injection of CCl4 (1 ml/kg) significantly attenuated increases in serum aspartate aminotransferase and alanine aminotransferase activities at 24 h after the CCl4 injection. Increases in hepatic lipid peroxide (LPO) concentrations and decreases in hepatic GSH concentrations after the CCl4 injection were significantly diminished by the gamma-GCE (160 micromol/kg) administration, but not by the same dose of GSH. Gamma-GCE, gamma-glutamylcysteine, and cysteine acted as substrates for glutathione peroxidases much less efficiently than GSH in the post-mitochondrial fraction of normal mouse liver cells. These results indicate that gamma-GCE attenuates the progression of CCl4-induced acute liver injury in mice through the maintenance of hepatic GSH levels, leading to inhibition of hepatic LPO formation, which could be due to an efficient utilization of GSH converted from gamma-GCE in the liver cells.

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

PubMed

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.

Mutagenic activation reduces carcinogenic activity of ortho-aminoazotoluene for mouse liver.

PubMed

Ovchinnikova, L P; Bogdanova, L A; Kaledin, V I

2013-03-01

Pentachlorophenol (aromatic amine and azo stain metabolic stimulation inhibitor) reduced the hepatocarcinogenic activity of 4-aminoazobenzene and reduced that of ortho-aminoazotoluene in suckling mice. Both 4-aminoazobenzene and ortho-aminoazotoluene exhibited mutagenic activity in Ames' test in vitro on S. typhimurium TA 98 strain with activation with liver enzymes; this mutagenic activity was similarly suppressed by adding pentachlorophenol into activation medium. Induction of xenobiotic metabolism enzymes, stimulating the mutagenic activity of ortho-aminoazotoluene, suppressed its carcinogenic effect on mouse liver. Hence, ortho-aminotoluene (the initial compound), but not its mutagenic metabolites, was the direct active hepatocarcinogen for mice.

Abacavir-induced liver toxicity.

PubMed

Pezzani, Maria Diletta; Resnati, Chiara; Di Cristo, Valentina; Riva, Agostino; Gervasoni, Cristina

2016-01-01

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. Copyright © 2016 Elsevier Editora Ltda. All rights reserved.

Study of fibrotic complications and hydroxyproline content in mouse liver at different stages of generalized BCG-induced granulomatosis.

PubMed

Shkurupii, V A; Kim, L B; Potapova, O V; Sharkova, T V; Putyatina, A N; Nikonova, I K

2014-08-01

Generalized BCG-induced granulomatous was simulated in BALB/c male mice. The number of tuberculous granulomas in the liver and their size as well as the number of hepatocytes showing vacuolar degeneration increased from day 3 to 180 postinfection. Necrotic changes in hepatocytes were most pronounced at the acute phase of inflammation (days 3 to 30). Proliferative processes in the liver parenchyma in the experimental group were less marked than in the control. Increased content of collagen fibers in the liver was determined by excessive collagen synthesis in necrotic areas as well as increased amount of granulomas and fibroblasts. Enhanced proliferative and fibroplastic activity of fibroblasts in granulomas and liver parenchyma was evidently determined by activated granuloma macrophages. These shifts determined changes in the liver content of hydroxyproline during the acute and chronic periods of the disease.

A novel ENU-induced mutation, peewee, causes dwarfism in the mouse

PubMed Central

Bon-Ryon, Lee; Kano, Kiyoshi; Young, Jay; John, Simon; Nishina, Patsy M; Naggert, Jurgen K; Naito, Kunihiko

2010-01-01

We identified a novel fertile, autosomal recessive mutation, called peewee and that results in dwarfing, in a region-specific ENU-induced mutagenesis. These mice at litter size were smaller those of other strains. Histological analysis revealed that the major organs appear normal, but abnormalities in cellular proliferation were observed in bone, liver and testis. Haplotype analysis localized the peewee gene to a 3.3-Mb region between D5Mit83 and D5Mit356.3. There are 18 genes in this linkage area, and we also performed in silico mapping using the PosMed℠ program, which searches for connections among keywords and genes in an interval, but no similar phenotype descriptions were found for these genes. In the peewee mutant compared to the normal, C57BL/6J mouse, only Slc10a4 expression was lower. Our preliminary mutation analysis examining the nucleotide sequence of three exons, two introns and an untranslated region of Slc10a4 did not find any sequence difference between the peewee mouse and the C57BL/6J mouse. Detailed analysis of peewee mice might provide novel molecular insights into the complex mechanisms regulating body growth. PMID:19513787

Spaceflight Activates Lipotoxic Pathways in Mouse Liver

PubMed Central

Jonscher, Karen R.; Alfonso-Garcia, Alba; Suhalim, Jeffrey L.; Orlicky, David J.; Potma, Eric O.; Ferguson, Virginia L.; Bouxsein, Mary L.; Bateman, Ted A.; Stodieck, Louis S.; Levi, Moshe; Friedman, Jacob E.; Gridley, Daila S.; Pecaut, Michael J.

2016-01-01

Spaceflight affects numerous organ systems in the body, leading to metabolic dysfunction that may have long-term consequences. Microgravity-induced alterations in liver metabolism, particularly with respect to lipids, remain largely unexplored. Here we utilize a novel systems biology approach, combining metabolomics and transcriptomics with advanced Raman microscopy, to investigate altered hepatic lipid metabolism in mice following short duration spaceflight. Mice flown aboard Space Transportation System -135, the last Shuttle mission, lose weight but redistribute lipids, particularly to the liver. Intriguingly, spaceflight mice lose retinol from lipid droplets. Both mRNA and metabolite changes suggest the retinol loss is linked to activation of PPARα-mediated pathways and potentially to hepatic stellate cell activation, both of which may be coincident with increased bile acids and early signs of liver injury. Although the 13-day flight duration is too short for frank fibrosis to develop, the retinol loss plus changes in markers of extracellular matrix remodeling raise the concern that longer duration exposure to the space environment may result in progressive liver damage, increasing the risk for nonalcoholic fatty liver disease. PMID:27097220

A mouse model of alcoholic liver fibrosis-associated acute kidney injury identifies key molecular pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Furuya, Shinji; Chappell, Grace A.; Iwata, Yasuhir

Clinical data strongly indicate that acute kidney injury (AKI) is a critical complication in alcoholic hepatitis, an acute-on-chronic form of liver failure in patients with advanced alcoholic fibrosis. Development of targeted therapies for AKI in this setting is hampered by the lack of an animal model. To enable research into molecular drivers and novel therapies for fibrosis- and alcohol-associated AKI, we aimed to combine carbon tetrachloride (CCl{sub 4})-induced fibrosis with chronic intra-gastric alcohol feeding. Male C57BL/6J mice were administered a low dose of CCl{sub 4} (0.2 ml/kg 2 × week/6 weeks) followed by alcohol intragastrically (up to 25 g/kg/day formore » 3 weeks) and with continued CCl{sub 4}. We observed that combined treatment with CCl{sub 4} and alcohol resulted in severe liver injury, more pronounced than using each treatment alone. Importantly, severe kidney injury was evident only in the combined treatment group. This mouse model reproduced distinct pathological features consistent with AKI in human alcoholic hepatitis. Transcriptomic analysis of kidneys revealed profound effects in the combined treatment group, with enrichment for damage-associated pathways, such as apoptosis, inflammation, immune-response and hypoxia. Interestingly, Havcr1 and Lcn2, biomarkers of AKI, were markedly up-regulated. Overall, this study established a novel mouse model of fibrosis- and alcohol-associated AKI and identified key mechanistic pathways. - Highlights: • Acute kidney injury (AKI) is a critical complication in alcoholic hepatitis • We developed a novel mouse model of fibrosis- and alcohol-associated AKI • This model reproduces key molecular and pathological features of human AKI • This animal model can help identify new targeted therapies for alcoholic hepatitis.« less

GGPPS deficiency aggravates CCl4-induced liver injury by inducing hepatocyte apoptosis.

PubMed

Chen, Wei-Bo; Lai, Shan-Shan; Yu, De-Cai; Liu, Jia; Jiang, Shan; Zhao, Dan-Dan; Ding, Yi-Tao; Li, Chao-Jun; Xue, Bin

2015-04-28

GGPPS catalyses the expression of GGPP, a key protein in the mevalonate metabolic pathway. HMG-CoA reductase inhibitor statins can induce liver injury by inhibiting GGPP. However, the function of GGPPS in liver injury has not yet been revealed. In this study, we found that GGPPS increased in liver injury and that GGPPS deletion augmented liver injury and fibrosis. GGPPS inhibition induced hepatocyte apoptosis, inflammation and TGF-β1 secretion, which activated hepatic stellate cells. Our findings imply that GGPPS deletion induces hepatocyte apoptosis, which makes the liver vulnerable to hepatotoxicity. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Growth hormone resistance exacerbates cholestasis-induced murine liver fibrosis

PubMed Central

Stiedl, Patricia; McMahon, Robert; Blaas, Leander; Stanek, Victoria; Svinka, Jasmin; Grabner, Beatrice; Zollner, Gernot; Kessler, Sonja M.; Claudel, Thierry; Müller, Mathias; Mikulits, Wolfgang; Bilban, Martin; Esterbauer, Harald; Eferl, Robert; Haybaeck, Johannes; Trauner, Michael; Casanova, Emilio

2016-01-01

Growth hormone (GH) resistance has been associated with liver cirrhosis in humans but its contribution to the disease remains controversial. In order to elucidate whether GH resistance plays a causal role in the establishment and development of liver fibrosis, or rather represents a major consequence thereof, we challenged mice lacking the Growth hormone receptor gene (Ghr-/-, a model for GH resistance) by crossing them with Mdr2 knockout mice (Mdr2-/-), a mouse model of inflammatory cholestasis and liver fibrosis. Ghr-/-;Mdr2-/- mice showed elevated serum markers associated with liver damage and cholestasis, extensive bile duct proliferation and increased collagen deposition relative to Mdr2 -/- mice, thus suggesting a more severe liver fibrosis phenotype. Additionally, Ghr-/-;Mdr2-/- mice had a pronounced down-regulation of hepato-protective genes Hnf6, Egfr and Igf-1, and significantly increased levels of ROS and apoptosis in hepatocytes, compared to control mice. Moreover, single knockout mice (Ghr-/-) fed with a diet containing 1% cholic acid displayed an increase in hepatocyte ROS production, hepatocyte apoptosis and bile infarcts compared to their wildtype littermates, indicating that loss of Ghr renders hepatocytes more susceptible to toxic bile acid accumulation. Surprisingly, and despite their severe fibrotic phenotype, Ghr-/-;Mdr2-/- mice displayed a significant decrease in tumour incidence compared to Mdr2-/- mice, indicating that loss of Ghr signaling may slow the progression from fibrosis/cirrhosis to cancer in the liver. Conclusion Our findings suggest that GH resistance dramatically exacerbates liver fibrosis in a mouse model of inflammatory cholestasis, therefore suggesting that GH resistance plays a causal role in the disease and provides a novel target for the development of liver fibrosis treatments. PMID:25179284

Interleukin-22 induces hepatic stellate cell senescence and restricts liver fibrosis in mice.

PubMed

Kong, Xiaoni; Feng, Dechun; Wang, Hua; Hong, Feng; Bertola, Adeline; Wang, Fu-Sheng; Gao, Bin

2012-09-01

Interleukin (IL)-22 is known to play a key role in promoting antimicrobial immunity, inflammation, and tissue repair at barrier surfaces by binding to the receptors, IL-10R2 and IL-22R1. IL-22R1 is generally thought to be expressed exclusively in epithelial cells. In this study, we identified high levels of IL-10R2 and IL-22R1 expression on hepatic stellate cells (HSCs), the predominant cell type involved in liver fibrogenesis in response to liver damage. In vitro treatment with IL-22 induced the activation of signal transducer and activator of transcription (STAT) 3 in primary mouse and human HSCs. IL-22 administration prevented HSC apoptosis in vitro and in vivo, but surprisingly, the overexpression of IL-22 by either gene targeting (e.g., IL-22 transgenic mice) or exogenous administration of adenovirus expressing IL-22 reduced liver fibrosis and accelerated the resolution of liver fibrosis during recovery. Furthermore, IL-22 overexpression or treatment increased the number of senescence-associated beta-galactosidase-positive HSCs and decreased alpha-smooth muscle actin expression in fibrotic livers in vivo and cultured HSCs in vitro. Deletion of STAT3 prevented IL-22-induced HSC senescence in vitro, whereas the overexpression of a constitutively activated form of STAT3 promoted HSC senescence through p53- and p21-dependent pathways. Finally, IL-22 treatment up-regulated the suppressor of cytokine signaling (SOCS) 3 expression in HSCs. Immunoprecipitation analyses revealed that SOCS3 bound p53 and subsequently increased the expression of p53 and its target genes, contributing to IL-22-mediated HSC senescence. IL-22 induces the senescence of HSCs, which express both IL-10R2 and IL-22R1, thereby ameliorating liver fibrogenesis. The antifibrotic effect of IL-22 is likely mediated by the induction of HSC senescence, in addition to the previously discovered hepatoprotective functions of IL-22. Copyright © 2012 American Association for the Study of Liver Diseases.

Evaluation of Aroclor 1260 exposure in a mouse model of diet-induced obesity and non-alcoholic fatty liver disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wahlang, Banrida; Song, Ming; Beier, Juliane I.

Polychlorinated biphenyls (PCBs) are persistent organic pollutants associated with non-alcoholic fatty liver disease (NAFLD) in epidemiologic studies. The purpose of this study was to evaluate the hepatic effects of a PCB mixture, Aroclor 1260, whose composition mimics human bioaccumulation patterns, in a mouse model of diet-induced obesity (DIO). Male C57Bl/6J mice were fed control diet or 42% high fat diet (HFD) and exposed to Aroclor 1260 (20 mg/kg or 200 mg/kg in corn oil) for 12 weeks. A glucose tolerance test was performed; plasma/tissues were obtained at necropsy for measurements of adipocytokine levels, histology, and gene expression. Aroclor 1260 exposuremore » was associated with decreased body fat in HFD-fed mice but had no effect on blood glucose/lipid levels. Paradoxically, Aroclor 1260 + HFD co-exposed mice demonstrated increased hepatic inflammatory foci at both doses while the degree of steatosis did not change. Serum cytokines, ALT levels and hepatic expression of IL-6 and TNFα were increased only at 20 mg/kg, suggesting an inhibition of pro-inflammatory cytokine production at the 200 mg/kg exposure. Aroclor 1260 induced hepatic expression of cytochrome P450s including Cyp3a11 (Pregnane-Xenobiotic Receptor target) and Cyp2b10 (constitutive androstane receptor target) but Cyp2b10 inducibility was diminished with HFD-feeding. Cyp1a2 (aryl hydrocarbon Receptor target) was induced only at 200 mg/kg. In summary, Aroclor 1260 worsened hepatic and systemic inflammation in DIO. The results indicated a bimodal response of PCB-diet interactions in the context of inflammation which could potentially be explained by xenobiotic receptor activation. Thus, PCB exposure may be a relevant “second hit” in the transformation of steatosis to steatohepatitis. - Highlights: • Aroclor 1260 exposure decreased adiposity in mice fed with high fat diet • Aroclor 1260 exposure induced steatohepatitis in diet-induced obese mice • Aroclor 1260 (20 and 200 mg

Esterase 22 and beta-glucuronidase hydrolyze retinoids in mouse liver

PubMed Central

Schreiber, Renate; Taschler, Ulrike; Wolinski, Heimo; Seper, Andrea; Tamegger, Stefanie N.; Graf, Maria; Kohlwein, Sepp D.; Haemmerle, Guenter; Zimmermann, Robert; Zechner, Rudolf; Lass, Achim

2009-01-01

Excess dietary vitamin A is esterified with fatty acids and stored in the form of retinyl ester (RE) predominantly in the liver. According to the requirements of the body, liver RE stores are hydrolyzed and retinol is delivered to peripheral tissues. The controlled mobilization of retinol ensures a constant supply of the body with the vitamin. Currently, the enzymes catalyzing liver RE hydrolysis are unknown. In this study, we identified mouse esterase 22 (Es22) as potent RE hydrolase highly expressed in the liver, particularly in hepatocytes. The enzyme is located exclusively at the endoplasmic reticulum (ER), implying that it is not involved in the mobilization of RE present in cytosolic lipid droplets. Nevertheless, cell culture experiments revealed that overexpression of Es22 attenuated the formation of cellular RE stores, presumably by counteracting retinol esterification at the ER. Es22 was previously shown to form a complex with β-glucuronidase (Gus). Our studies revealed that Gus colocalizes with Es22 at the ER but does not affect its RE hydrolase activity. Interestingly, however, Gus was capable of hydrolyzing the naturally occurring vitamin A metabolite retinoyl β-glucuronide. In conclusion, our observations implicate that both Es22 and Gus play a role in liver retinoid metabolism. PMID:19723663

Comparative Analysis of the Relationship between Trichloroethylene Metabolism and Tissue-Specific Toxicity among Inbred Mouse Strains: Liver Effects

PubMed Central

Yoo, Hong Sik; Bradford, Blair U.; Kosyk, Oksana; Shymonyak, Svitlana; Uehara, Takeki; Collins, Leonard B.; Bodnar, Wanda M.; Ball, Louise M.; Gold, Avram; Rusyn, Ivan

2014-01-01

Trichloroethylene (TCE) is a widely used organic solvent. Although TCE is classified as carcinogenic to humans, substantial gaps remain in our understanding of inter-individual variability in TCE metabolism and toxicity, especially in the liver. We tested a hypothesis that amounts of oxidative metabolites of TCE in mouse liver are associated with liver-specific toxicity. Oral dosing with TCE was conducted in sub-acute (600 mg/kg/d; 5 days; 7 inbred mouse strains) and sub-chronic (100 or 400 mg/kg/d; 1, 2, or 4 weeks; 2 inbred mouse strains) designs. We evaluated the quantitative relationship between strain-, dose-, and time-dependent formation of TCE metabolites from cytochrome P450-mediated oxidation [trichloroacetic acid (TCA), dichloroacetic acid (DCA), and trichloroethanol] and glutathione conjugation [S-(1,2-dichlorovinyl)-L-cysteine and S-(1,2-dichlorovinyl)glutathione] in serum and liver, and various liver toxicity phenotypes. In sub-acute study, inter-strain variability in TCE metabolite amounts was observed in serum and liver. No induction of Cyp2e1 protein levels in liver was detected. Serum and liver levels of TCA and DCA were correlated with increased transcription of peroxisome proliferator-marker genes Cyp4a10 and Acox1, but not with degree of induction in hepatocellular proliferation. In sub-chronic study, serum and liver levels of oxidative metabolites gradually decreased over time despite continuous dosing. Liver protein levels of Cyp2e1, Adh and Aldh2 were unaffected by treatment with TCE. While the magnitude of induction of peroxisome proliferator-marker genes also declined, hepatocellular proliferation increased. This study offers a unique opportunity to provide a scientific data-driven rationale for some of the major assumptions in human health assessment of TCE. PMID:25424544

CYP1A1 and CYP1A2 expression: Comparing 'humanized' mouse lines and wild-type mice; comparing human and mouse hepatoma-derived cell lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uno, Shigeyuki; Endo, Kaori; Ishida, Yuji

2009-05-15

Human and rodent cytochrome P450 (CYP) enzymes sometimes exhibit striking species-specific differences in substrate preference and rate of metabolism. Human risk assessment of CYP substrates might therefore best be evaluated in the intact mouse by replacing mouse Cyp genes with human CYP orthologs; however, how 'human-like' can human gene expression be expected in mouse tissues? Previously a bacterial-artificial-chromosome-transgenic mouse, carrying the human CYP1A1{sub C}YP1A2 locus and lacking the mouse Cyp1a1 and Cyp1a2 orthologs, was shown to express robustly human dioxin-inducible CYP1A1 and basal versus inducible CYP1A2 (mRNAs, proteins, enzyme activities) in each of nine mouse tissues examined. Chimeric mice carryingmore » humanized liver have also been generated, by transplanting human hepatocytes into a urokinase-type plasminogen activator(+/+){sub s}evere-combined-immunodeficiency (uPA/SCID) line with most of its mouse hepatocytes ablated. Herein we compare basal and dioxin-induced CYP1A mRNA copy numbers, protein levels, and four enzymes (benzo[a]pyrene hydroxylase, ethoxyresorufin O-deethylase, acetanilide 4-hydroxylase, methoxyresorufin O-demethylase) in liver of these two humanized mouse lines versus wild-type mice; we also compare these same parameters in mouse Hepa-1c1c7 and human HepG2 hepatoma-derived established cell lines. Most strikingly, mouse liver CYP1A1-specific enzyme activities are between 38- and 170-fold higher than human CYP1A1-specific enzyme activities (per unit of mRNA), whereas mouse versus human CYP1A2 enzyme activities (per unit of mRNA) are within 2.5-fold of one another. Moreover, both the mouse and human hepatoma cell lines exhibit striking differences in CYP1A mRNA levels and enzyme activities. These findings are relevant to risk assessment involving human CYP1A1 and CYP1A2 substrates, when administered to mice as environmental toxicants or drugs.« less

Herbal and Dietary Supplement Induced Liver Injury

PubMed Central

de Boer, Ynto S.; Sherker, Averell H.

2016-01-01

Summary The increase in the use of herbal and dietary supplements (HDS) over the last decades has been accompanied with an increase in the reports of HDS associated hepatotoxicity. The spectrum of HDS induced liver injury is diverse and the outcome may vary from transient liver test elevations to fulminant hepatic failure resulting in death or requiring liver transplantation. There are no validated standardized tools to establish the diagnosis, but some HDS products do have a typical clinical signature that may help to identify HDS induced liver injury. PMID:27842768

Chlorogenic acid protects D-galactose-induced liver and kidney injury via antioxidation and anti-inflammation effects in mice.

PubMed

Feng, Yan; Yu, Ying-Hua; Wang, Shu-Ting; Ren, Jing; Camer, Danielle; Hua, Yu-Zhou; Zhang, Qian; Huang, Jie; Xue, Dan-Lu; Zhang, Xiao-Fei; Huang, Xu-Feng; Liu, Yi

2016-01-01

Oxidative stress and inflammation are implicated in the aging process and its related hepatic and renal function decline. Chlorogenic acid (CGA) is one of the most abundant polyphenol compounds in the human diet. Recently, CGA has shown in vivo and in vitro antioxidant properties. The current study investigates the effects of protective effects of chlorogenic acid (CGA) on D-galactose-induced liver and kidney injury. Hepatic and renal injuries were induced in a mouse model by subcutaneously injection of D-galactose (D-gal; 100 mg/kg) once a day for 8 consecutive weeks and orally administered simultaneously with CGA included in the food (200 mg/kg of diet). The liver and renal functions were examined. Histological analyses of liver and kidney were done by haematoxylin and eosin staining. The oxidative stress markers and pro-inflammatory cytokines in the liver and the kidney were measured. Results CGA significantly reduced the serum aminotransferase, serum creatinine (SCr) and blood urea nitrogen (BUN) levels in D-gal mice (p <0.05). CGA also restored superoxide dismutase, catalase, and malondialdehyde levels and decreased glutathione content in the liver and kidney in D-gal mice (p <0.05). Improvements in liver and kidney were also noted in histopathological studies. CGA reduced tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) protein levels in the liver and kidney in D-gal mice (p <0.05). These findings suggest that CGA attenuates D-gal-induced chronic liver and kidney injury and that this protection may be due to its antioxidative and anti-inflammatory activities.

Fatty acid binding protein-4 (FABP4) is a hypoxia inducible gene that sensitizes mice to liver ischemia/reperfusion injury.

PubMed

Hu, Bingfang; Guo, Yan; Garbacz, Wojciech G; Jiang, Mengxi; Xu, Meishu; Huang, Hai; Tsung, Allan; Billiar, Timothy R; Ramakrishnan, Sadeesh K; Shah, Yatrik M; Lam, Karen S L; Huang, Min; Xie, Wen

2015-10-01

Fatty acid binding protein 4 (FABP4) has been known as a mediator of inflammatory response in the macrophages and adipose tissue, but its hepatic function is poorly understood. The goal of this study is to investigate the role of FABP4 in liver ischemia/reperfusion (I/R), a clinical condition that involves both hypoxia and inflammation. To examine the I/R regulation of FABP4, mice were subjected to I/R surgery before being measured for FABP4 gene expression. Both loss-of-function (by using a pharmacological FABP4 inhibitor) and gain-of-function (by adenoviral overexpression of FABP4) were used to determine the functional relevance of FABP4 expression and its regulation during I/R. To determine the hypoxia responsive regulation of FABP4, primary mouse hepatocytes were exposed to hypoxia. The FABP4 gene promoter was cloned and its regulation by hypoxia inducible factor 1α (HIF-1α) was characterized by luciferase reporter gene, electrophoretic mobility shift, and chromatin immunoprecipitation assays. We found that the hepatic expression of FABP4 was markedly induced by I/R. At the functional level, pharmacological inhibition of FABP4 alleviated the I/R injury, whereas adenoviral overexpression of FABP4 sensitized mice to I/R injury. We also showed that exposure of primary hepatocytes to hypoxia or transgenic overexpression of HIF-1α in the mouse liver was sufficient to induce the expression of FABP4. Our promoter analysis established FABP4 as a novel transcriptional target of HIF-1α. FABP4 is a hypoxia inducible gene that sensitizes mice to liver I/R injury. FABP4 may represent a novel therapeutic target, and FABP4 inhibitors may be used as therapeutic agents to manage hepatic I/R injury. Copyright © 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Morphological and immunobiochemical analysis of the liver in L-arginine induced experimental chronic pancreatitis.

PubMed

Hu, Na; Shen, Yicong; Liu, Fengyu; Wu, Jiuping; Yuan, Feng; Tian, Liwei; Wu, Bo; Chen, Guoqing; Zhang, Jianming; Wang, Jun

Clinical evidence indicates that hepatic abnormalities in patients with chronic pancreatitis are not uncommon. Here we aimed to study the possible association between liver and pancreatic damage in a recently described experimental mouse model of CP. The severity of the damage to pancreas, liver and other organs was assessed by biochemical markers and histopathology. The methods applied included Hematoxylin Eosin staining, electron microscope examination, biochemical measurements, RT-PCR, ELISA, and the correlations among some of the parameters contributing to these changes were statistically analyzed. The hepatic aberrations were mainly represented by mild infiltration of inflammatory cells in portal triad and congestion of central vein of liver, and the main features of drug-induced hepatotoxicity could not be observed. Severe fibrosis of pancreatic tissue was noticed in experimental group, and the existence of multiple organ injuries was also seen under the microscope. Hepatic pathologic scores were positively correlated with those from the corresponding pancreatic specimens (r = 0.72, P < 0.01). TGF-β1 protein levels significantly elevated both in the test pancreas and liver (P < 0.05) and these values were positively correlated (r = 0.86, P < 0.01). The level of interleukin-1β was increased in the serum and tissue of the liver. In addition, cardiac troponin (Tn-I) level not only significantly increased in myocardial homogenates (P < 0.05) but also was positively correlated with the corresponding pathologic score of the liver (r = 0.88, P < 0.01). The liver aberrations might be associated with L-arginine induced chronic pancreatitis. Copyright © 2017 IAP and EPC. Published by Elsevier B.V. All rights reserved.

CYP1A1 and CYP1A2 expression: Comparing ‘humanized’ mouse lines and wild-type mice; comparing human and mouse hepatoma-derived cell lines

PubMed Central

Uno, Shigeyuki; Endo, Kaori; Ishida, Yuji; Tateno, Chise; Makishima, Makoto; Yoshizato, Katsutoshi; Nebert, Daniel W.

2009-01-01

Human and rodent cytochrome P450 (CYP) enzymes sometimes exhibit striking species-specific differences in substrate preference and rate of metabolism. Human risk assessment of CYP substrates might therefore best be evaluated in the intact mouse by replacing mouse Cyp genes with human CYP orthologs; however, how “human-like” can human gene expression be expected in mouse tissues? Previously a bacterial-artificial-chromosome-transgenic mouse, carrying the human CYP1A1_CYP1A2 locus and lacking the mouse Cyp1a1 and Cyp1a2 orthologs, was shown to express robustly human dioxin-inducible CYP1A1 and basal versus inducible CYP1A2 (mRNAs, proteins, enzyme activities) in each of nine mouse tissues examined. Chimeric mice carrying humanized liver have also been generated, by transplanting human hepatocytes into a urokinase-type plasminogen activator(+/+)_severe-combined-immunodeficiency (uPA/SCID) line with most of its mouse hepatocytes ablated. Herein we compare basal and dioxin-induced CYP1A mRNA copy numbers, protein levels, and four enzymes (benzo[a]pyrene hydroxylase, ethoxyresorufin O-deethylase, acetanilide 4-hydroxylase, methoxyresorufin O-demethylase) in liver of these two humanized mouse lines versus wild-type mice; we also compare these same parameters in mouse Hepa-1c1c7 and human HepG2 hepatoma-derived established cell lines. Most strikingly, mouse liver CYP1A1-specific enzyme activities are between 38- and 170-fold higher than human CYP1A1-specific enzyme activities (per unit of mRNA), whereas mouse versus human CYP1A2 enzyme activities (per unit of mRNA) are within 2.5-fold of one another. Moreover, both the mouse and human hepatoma cell lines exhibit striking differences in CYP1A mRNA levels and enzyme activities. These findings are relevant to risk assessment involving human CYP1A1 and CYP1A2 substrates, when administered to mice as environmental toxicants or drugs. PMID:19285097

Impaired TFEB-mediated Lysosome Biogenesis and Autophagy Promote Chronic Ethanol-induced Liver Injury and Steatosis in Mice.

PubMed

Chao, Xiaojuan; Wang, Shaogui; Zhao, Katrina; Li, Yuan; Williams, Jessica A; Li, Tiangang; Chavan, Hemantkumar; Krishnamurthy, Partha; He, Xi C; Li, Linheng; Ballabio, Andrea; Ni, Hong-Min; Ding, Wen-Xing

2018-05-18

Defects in lysosome function and autophagy contribute to pathogenesis of alcoholic liver disease. We investigated the mechanisms by which alcohol consumption affects these processes, evaluating the functions transcription factor EB (TFEB), which regulates lysosomal biogenesis. We performed studies with GFP-LC3 mice, mice with liver-specific deletion of transcription factor EB (TFEB), mice with disruption of the transcription factor E3 gene (TFE3-knockout mice), mice with disruption of the Tefb and Tfe3 genes (TFEB, TFE3 double-knockout mice), and Tfeb flox/flox albumin cre-negative mice (controls). TFEB was overexpressed from adenoviral vectors or knocked down with small interfering RNAs in mouse livers. Mice were placed on diets of chronic ethanol feeding plus an acute binge to induce liver damage (ethanol diet); some mice were also given injections of torin1, an inhibitor of the kinase activity of the mechanistic target of rapamycin (mTOR). Liver tissues were collected and analyzed by immunohistochemistry, immunoblots, and quantitative real-time PCR to monitor lysosome biogenesis. We analyzed levels of TFEB in liver tissues from patients with alcoholic hepatitis and from healthy donors (controls) by immunohistochemistry. Liver tissues from mice on the ethanol diet had lower levels of total and nuclear TFEB, compared with control mice, and hepatocytes had reduced lysosome biogenesis and autophagy. Hepatocytes from mice on the ethanol diet had increased translocation of mTOR into lysosomes, resulting increased mTOR activation. Administration of torin1 increased liver levels of TFEB and reduced steatosis and liver injury induced by ethanol. Mice that overexpressed TFEB in liver developed less-severe ethanol-induced liver injury and had increased lysosomal biogenesis and mitochondrial bioenergetics compared to mice carrying a control vector. Mice with knockdown of TFEB, as well as TFEB, TFE3 double-knockout mice, developed more severe liver injury in response to the

A Chimeric Humanized Mouse Model by Engrafting the Human Induced Pluripotent Stem Cell-Derived Hepatocyte-Like Cell for the Chronic Hepatitis B Virus Infection

PubMed Central

Yuan, Lunzhi; Liu, Xuan; Zhang, Liang; Li, Xiaoling; Zhang, Yali; Wu, Kun; Chen, Yao; Cao, Jiali; Hou, Wangheng; Zhang, Jun; Zhu, Hua; Yuan, Quan; Tang, Qiyi; Cheng, Tong; Xia, Ningshao

2018-01-01

Humanized mouse model generated by grafting primary human hepatocytes (PHHs) to immunodeficient mouse has contributed invaluably to understanding the pathogenesis of hepatitis B virus (HBV). However, the source of PHHs is limited, which necessitates the search for alternatives. Recently, hepatocyte-like cells (HLCs) generated from human induced pluripotent stem cells (hiPSCs) have been used for in vitro HBV infection. Herein, we developed a robust human liver chimeric animal model to study in vivo HBV infection by engrafting the hiPSC-HLCs to Fah-/-Rag2-/-IL-2Rγc-/- SCID (FRGS) mice. After being optimized by a small molecule, XMU-MP-1, the hiPSC-HLCs engrafted FRGS (hHLC-FRGS) mice displayed approximately 40% liver chimerism at week 6 after engraftment and maintained at this level for at least 14 weeks. Viremia and HBV infection markers include antigens, RNA, DNA, and covalently closed circular DNA were detectable in HBV infected hHLC-FRGS mice. Furthermore, hiPSC-HLCs and hHLC-FRGS mice were successfully used to evaluate different antivirals. Therefore, we established a humanized mouse model for not only investigating HBV pathogenesis but also testing the effects of the anti-HBV drugs. Highlights:    (1) The implanted hiPSC-HLCs established a long-term chimerism in FRGS mice liver.    (2) hHLC-FRGS mice are adequate to support chronic HBV infection with a full viral life cycle.    (3) hiPSC-HLCs and hHLC-FRGS mice are useful tools for evaluation of antivirals against HBV infection in vitro and in vivo. Research in Context  To overcome the disadvantages of using primary human hepatocytes, we induced human pluripotent stem cells to hepatocyte-like cells (hiPSC-HLCs) that developed the capability to express important liver functional markers and critical host factors for HBV infection. The hiPSC-HLCs were permissive for the HBV infection and supported a full HBV replication. The hiPSC-HLCs were then engrafted to immunodeficient mouse to establish a

Bacoside A downregulates matrix metalloproteinases 2 and 9 in DEN-induced hepatocellular carcinoma.

PubMed

Janani, Panneerselvam; Sivakumari, Kanakarajan; Geetha, Arumugam; Yuvaraj, Sambandam; Parthasarathy, Chandrakesan

2010-03-01

Cancer metastasis is a complex multi-step process, responsible for a majority of cancer-related deaths by affecting the critical organs and causing complications in therapies. Hepatocellular carcinoma is a multi-factorial disease and is the third most common cause of cancer related mortality worldwide. Clinical and experimental studies have shown that MMP-2 and MMP-9 are involved in tumor invasion and metastases and their elevated expression has been associated with poor prognosis. Our recent studies showed a strong anti-oxidant and hepatoprotective effects of bacoside A (BA) against carcinogen. Nevertheless the effect of BA on the activities and expression of MMP-2 and MMP-9 during hepatocellular carcinoma is not yet recognized. Therefore, the present study was designed to assess the same. Results of gelatin zymography study showed that BA co-treatment significantly decreased the activities of MMP-2 and MMP-9, which is increased during hepatocellular carcinoma. Further immunoblot analysis showed decreased expression of MMP-2 and MMP-9 in rats co-treated with BA compared to DEN-induced hepatocellular carcinoma. Our results reveal that BA exerts its anti-metastatic effect against DEN-induced hepatocellular carcinoma by inhibiting the activities and expressions of MMP-2 and MMP-9. 2010 John Wiley & Sons, Ltd.

BOK promotes chemical-induced hepatocarcinogenesis in mice.

PubMed

Rabachini, Tatiana; Fernandez-Marrero, Yuniel; Montani, Matteo; Loforese, Giulio; Sladky, Valentina; He, Zhaoyue; Bachmann, Daniel; Wicki, Simone; Villunger, Andreas; Stroka, Deborah; Kaufmann, Thomas

2018-03-01

BCL-2-related ovarian killer (BOK) is a conserved and widely expressed BCL-2 family member with sequence homology to pro-apoptotic BAX and BAK, but with poorly understood pathophysiological function. Since several members of the BCL-2 family are critically involved in the regulation of hepatocellular apoptosis and carcinogenesis we aimed to establish whether loss of BOK affects diethylnitrosamine (DEN)-induced hepatocarcinogenesis in mice. Short-term exposure to DEN lead to upregulation of BOK mRNA and protein in the liver. Of note, induction of CHOP and the pro-apoptotic BH3-only proteins PUMA and BIM by DEN was strongly reduced in the absence of BOK. Accordingly, Bok -/- mice were significantly protected from DEN-induced acute hepatocellular apoptosis and associated inflammation. As a consequence, Bok -/- animals were partially protected against chemical-induced hepatocarcinogenesis showing fewer and, surprisingly, also smaller tumors than WT controls. Gene expression profiling revealed that downregulation of BOK results in upregulation of genes involved in cell cycle arrest. Bok -/- hepatocellular carcinoma (HCC) displayed higher expression levels of the cyclin kinase inhibitors p19 INK4d and p21 cip1 . Accordingly, hepatocellular carcinoma in Bok -/- animals, BOK-deficient human HCC cell lines, as well as non-transformed cells, showed significantly less proliferation than BOK-proficient controls. We conclude that BOK is induced by DEN, contributes to DEN-induced hepatocellular apoptosis and resulting hepatocarcinogenesis. In line with its previously reported predominant localization at the endoplasmic reticulum, our findings support a role of BOK that links the cell cycle and cell death machineries upstream of mitochondrial damage.

Tunicamycin-induced unfolded protein response in the developing mouse brain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Haiping; Wang, Xin; Ke, Zun-Ji

Accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) causes ER stress, resulting in the activation of the unfolded protein response (UPR). ER stress and UPR are associated with many neurodevelopmental and neurodegenerative disorders. The developing brain is particularly susceptible to environmental insults which may cause ER stress. We evaluated the UPR in the brain of postnatal mice. Tunicamycin, a commonly used ER stress inducer, was administered subcutaneously to mice of postnatal days (PDs) 4, 12 and 25. Tunicamycin caused UPR in the cerebral cortex, hippocampus and cerebellum of mice of PD4 and PD12, which was evident bymore » the upregulation of ATF6, XBP1s, p-eIF2α, GRP78, GRP94 and MANF, but failed to induce UPR in the brain of PD25 mice. Tunicamycin-induced UPR in the liver was observed at all stages. In PD4 mice, tunicamycin-induced caspase-3 activation was observed in layer II of the parietal and optical cortex, CA1–CA3 and the subiculum of the hippocampus, the cerebellar external germinal layer and the superior/inferior colliculus. Tunicamycin-induced caspase-3 activation was also shown on PD12 but to a much lesser degree and mainly located in the dentate gyrus of the hippocampus, deep cerebellar nuclei and pons. Tunicamycin did not activate caspase-3 in the brain of PD25 mice and the liver of all stages. Similarly, immature cerebellar neurons were sensitive to tunicamycin-induced cell death in culture, but became resistant as they matured in vitro. These results suggest that the UPR is developmentally regulated and the immature brain is more susceptible to ER stress. - Highlights: • Tunicamycin caused a development-dependent UPR in the mouse brain. • Immature brain was more susceptible to tunicamycin-induced endoplasmic reticulum stress. • Tunicamycin caused more neuronal death in immature brain than mature brain. • Tunicamycin-induced neuronal death is region-specific.« less

Protection of the liver against CCl4-induced injury by intramuscular electrotransfer of a kallistatin-encoding plasmid.

PubMed

Diao, Yong; Zhao, Xiao-Feng; Lin, Jun-Sheng; Wang, Qi-Zhao; Xu, Rui-An

2011-01-07

To investigate the effect of transgenic expression of kallistatin (Kal) on carbon tetrachloride (CCl(4))-induced liver injury by intramuscular (im) electrotransfer of a Kal-encoding plasmid formulated with poly-L-glutamate (PLG). The pKal plasmid encoding Kal gene was formulated with PLG and electrotransferred into mice skeletal muscle before the administration of CCl4. The expression level of Kal was measured. The serum biomarker levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), malonyldialdehyde (MDA), and tumor necrosis factor (TNF)-α were monitored. The extent of CCl4-induced liver injury was analyzed histopathologically. The transgene of Kal was sufficiently expressed after an im injection of plasmid formulated with PLG followed by electroporation. In the Kal gene-transferred mice, protection against CCl4-induced liver injury was reflected by significantly decreased serum ALT, AST, MDA and TNF-α levels compared to those in control mice (P<0.01 to 0.05 in a dose-dependent manner). Histological observations also revealed that hepatocyte necrosis, hemorrhage, vacuolar change and hydropic degeneration were apparent in mice after CCl4 administration. In contrast, the damage was markedly attenuated in the Kal gene-transferred mice. The expression of hepatic fibrogenesis marker transforming growth factor-β1 was also reduced in the pKal transferred mice. Intramuscular electrotransfer of plasmid pKal which was formulated with PLG significantly alleviated the CCl4-induced oxidative stress and inflammatory response, and reduced the liver damage in a mouse model.

Dietary Broccoli Lessens Development of Fatty Liver and Liver Cancer in Mice Given Diethylnitrosamine and Fed a Western or Control Diet.

PubMed

Chen, Yung-Ju; Wallig, Matthew A; Jeffery, Elizabeth H

2016-03-01

The high-fat and high-sugar Westernized diet that is popular worldwide is associated with increased body fat accumulation, which has been related to the development of nonalcoholic fatty liver disease (NAFLD). Without treatment, NAFLD may progress to hepatocellular carcinoma (HCC), a cancer with a high mortality rate. The consumption of broccoli in the United States has greatly increased in the last 2 decades. Epidemiologic studies show that incorporating brassica vegetables into the daily diet lowers the risk of several cancers, although, to our knowledge, this is the first study to evaluate HCC prevention through dietary broccoli. We aimed to determine the impact of dietary broccoli on hepatic lipid metabolism and the progression of NAFLD to HCC. Our hypothesis was that broccoli decreases both hepatic lipidosis and the development of HCC in a mouse model of Western diet-enhanced liver cancer. Adult 5-wk-old male B6C3F1 mice received a control diet (AIN-93M) or a Western diet (high in lard and sucrose, 19% and 31%, wt:wt, respectively), with or without freeze-dried broccoli (10%, wt:wt). Starting the following week, mice were treated once per week with diethylnitrosamine (DEN; 45 mg/kg body weight intraperitoneally at ages 6, 7, 8, 10, 11, and 12 wk). Hepatic gene expression, lipidosis, and tumor outcomes were analyzed 6 mo later, when mice were 9 mo old. Mice receiving broccoli exhibited lower hepatic triglycerides (P < 0.001) and NAFLD scores (P < 0.0001), decreased plasma alanine aminotransferase (P < 0.0001), suppressed activation of hepatic CD68(+) macrophages (P < 0.0001), and slowed initiation and progression of hepatic neoplasm. Hepatic Cd36 was downregulated by broccoli feeding (P = 0.006), whereas microsomal triglyceride transfer protein was upregulated (P = 0.045), supporting the finding that dietary broccoli decreased hepatic triglycerides. Long-term consumption of whole broccoli countered both NAFLD development enhanced by a Western diet and hepatic

Nuclear Receptor CAR Specifically Activates the Two-Pore K+ Channel Kcnk1 Gene in Male Mouse Livers, Which Attenuates Phenobarbital-Induced Hepatic Hyperplasia

PubMed Central

Negishi, Masahiko

2013-01-01

KCNK1, a member of the family of two-pore K+ ion channels, is specifically induced in the livers of male mice after phenobarbital treatment. Here, we have determined the molecular mechanism of this male-specific activation of the Kcnk1 gene and characterized KCNK1 as a phenobarbital-inducible antihyperplasia factor. Upon activation by phenobarbital, nuclear receptor CAR binds the 97-bp response element (−2441/−2345) within the Kcnk1 promoter. This binding is observed in the livers of male mice, but not in the livers of female mice and requires the pituitary gland, because hypophysectomy abrogates it. Hyperplasia further progressed in the livers of Kcnk1 −/− male mice compared with those of Kcnk1 +/+ males after phenobarbital treatment. Thus, KCNK1 suppresses phenobarbital-induced hyperplasia. These results indicate that phenobarbital treatment induces KCNK1 to elicit a male-specific and growth-suppressing signal. Thus, KCNK1 and Kcnk1 −/− mice provide an experimental tool for further investigation into the molecular mechanism of CAR-mediated promotion of the development of hepatocellular carcinoma in mice. PMID:23291559

Nuclear receptor CAR specifically activates the two-pore K+ channel Kcnk1 gene in male mouse livers, which attenuates phenobarbital-induced hepatic hyperplasia.

PubMed

Saito, Kosuke; Moore, Rick; Negishi, Masahiko

2013-03-01

KCNK1, a member of the family of two-pore K(+) ion channels, is specifically induced in the livers of male mice after phenobarbital treatment. Here, we have determined the molecular mechanism of this male-specific activation of the Kcnk1 gene and characterized KCNK1 as a phenobarbital-inducible antihyperplasia factor. Upon activation by phenobarbital, nuclear receptor CAR binds the 97-bp response element (-2441/-2345) within the Kcnk1 promoter. This binding is observed in the livers of male mice, but not in the livers of female mice and requires the pituitary gland, because hypophysectomy abrogates it. Hyperplasia further progressed in the livers of Kcnk1 ( -/- ) male mice compared with those of Kcnk1 ( +/+ ) males after phenobarbital treatment. Thus, KCNK1 suppresses phenobarbital-induced hyperplasia. These results indicate that phenobarbital treatment induces KCNK1 to elicit a male-specific and growth-suppressing signal. Thus, KCNK1 and Kcnk1 ( -/- ) mice provide an experimental tool for further investigation into the molecular mechanism of CAR-mediated promotion of the development of hepatocellular carcinoma in mice.

Anti-VEGF therapy induces ECM remodeling and mechanical barriers to therapy in colorectal cancer liver metastases.

PubMed

Rahbari, Nuh N; Kedrin, Dmitriy; Incio, Joao; Liu, Hao; Ho, William W; Nia, Hadi T; Edrich, Christina M; Jung, Keehoon; Daubriac, Julien; Chen, Ivy; Heishi, Takahiro; Martin, John D; Huang, Yuhui; Maimon, Nir; Reissfelder, Christoph; Weitz, Jurgen; Boucher, Yves; Clark, Jeffrey W; Grodzinsky, Alan J; Duda, Dan G; Jain, Rakesh K; Fukumura, Dai

2016-10-12

The survival benefit of anti-vascular endothelial growth factor (VEGF) therapy in metastatic colorectal cancer (mCRC) patients is limited to a few months because of acquired resistance. We show that anti-VEGF therapy induced remodeling of the extracellular matrix with subsequent alteration of the physical properties of colorectal liver metastases. Preoperative treatment with bevacizumab in patients with colorectal liver metastases increased hyaluronic acid (HA) deposition within the tumors. Moreover, in two syngeneic mouse models of CRC metastasis in the liver, we show that anti-VEGF therapy markedly increased the expression of HA and sulfated glycosaminoglycans (sGAGs), without significantly changing collagen deposition. The density of these matrix components correlated with increased tumor stiffness after anti-VEGF therapy. Treatment-induced tumor hypoxia appeared to be the driving force for the remodeling of the extracellular matrix. In preclinical models, we show that enzymatic depletion of HA partially rescued the compromised perfusion in liver mCRCs after anti-VEGF therapy and prolonged survival in combination with anti-VEGF therapy and chemotherapy. These findings suggest that extracellular matrix components such as HA could be a potential therapeutic target for reducing physical barriers to systemic treatments in patients with mCRC who receive anti-VEGF therapy. Copyright © 2016, American Association for the Advancement of Science.

Effects of butyric acid and arsenic on isolated pancreatic islets and liver mitochondria of male mouse

PubMed Central

Ahangarpour, Akram; Oroojan, Ali Akbar; Rezae, Mohsen; Khodayar, Mohammad Javad; Alboghobeish, Soheila; Zeinvand, Marzieh

2017-01-01

Aim: The aim of the present study was to evaluate the different doses of Butyric acid (BA) and Arsenic (As) in liver mitochondria oxidative stress and pancreatic islet insulin secretion of male mouse. Background: BA is found in many foods and As as a toxic metal is present in drinking water. They can induce oxidative stress in tissues. Methods: In this experimental study, Liver mitochondria were isolated by administration of the different centrifugation method and pancreatic islets were isolated by collagenase method. Mitochondria were incubated by BA (35, 75, 150, 300 μM) and As (20, 50, 100, 200 μM) as the islets were incubated by BA (250, 500, 1000, 1500 μM) and As (50, 100, 200 μM) for 1 hour. At the end of the experiment, mitochondrial viability and membrane potential, ROS, MDA, GSH and islets insulin secretion were measured by their specific methods. Results: BA and As administration increased mitochondrial levels of ROS, MDA and decreased GSH and pancreatic islet insulin secretion in a dose dependent manner (p<0.05). The doses of BA 75μM and As 100μM have been revealed the most mitochondria toxic concentrations. Also, the doses of 1000μM for BA and 100μM for As were considered as reducing concentrations for islets insulin secretion. Additionally, co administration of them intensified more these effects Conclusion: Alone or in combination administration of BA and As induced oxidative stress in liver mitochondria and decreased insulin secretion of pancreatic islets. PMID:28331564

Hepatic progenitor cells of biliary origin with liver repopulation capacity

PubMed Central

Boulter, Luke; Tsuchiya, Atsunori; Cole, Alicia M; Hay, Trevor; Guest, Rachel V; Wojtacha, Davina; Man, Tak Yung; Mackinnon, Alison; Ridgway, Rachel A; Kendall, Timothy; Williams, Michael J; Jamieson, Thomas; Raven, Alex; Hay, David C; Iredale, John P; Clarke, Alan R; Sansom, Owen J; Forbes, Stuart J

2015-01-01

Summary Hepatocytes and cholangiocytes self renew following liver injury. Following severe injury hepatocytes are increasingly senescent, whether Hepatic Progenitor Cells (HPCs) then contribute to liver regeneration is unclear. Here, we describe a mouse model where Mdm2 is inducibly deleted in over 98% of hepatocytes, causing apoptosis, necrosis and senescence with nearly all hepatocytes expressing p21. This results in florid HPC activation, which is necessary for survival, followed by complete, functional liver reconstitution. HPCs isolated from genetically normal mice, using cell surface markers, were highly expandable and phenotypically stable in vitro. These HPCs were transplanted into adult mouse livers where hepatocyte Mdm2 was repeatedly deleted, creating a non-competitive repopulation assay. Transplanted HPCs contributed significantly to restoration of liver parenchyma, regenerating hepatocytes and biliary epithelia, highlighting their in vivo lineage potency. HPCs are therefore a potential future alternative to hepatocyte or liver transplantation for liver disease. PMID:26192438

Prevention of rat liver fibrosis and carcinogenesis by coffee and caffeine.

PubMed

Furtado, Kelly S; Polletini, Jossimara; Dias, Marcos C; Rodrigues, Maria A M; Barbisan, Luis F

2014-02-01

Coffee has been inversely related to the incidence of human liver disease; however, whether caffeine is the component responsible for the beneficial effects of coffee remains controversial. This study evaluated the beneficial effects of coffee or caffeine in a medium-term bioassay for rat liver fibrosis/carcinogenesis induced by diethylnitrosamine (DEN) and carbon tetrachloride (CCl4). One week after the DEN injection, the groups started to receive conventional coffee, instant coffee or 0.1% caffeine ad libitum for 24 weeks. The groups receiving conventional coffee or caffeine presented a significant reduction in collagen content and mRNA expression of collagen I. The groups receiving instant coffee or caffeine had a significant reduction in the size and area of pre-neoplastic lesions and in the mean number of neoplastic lesions. A significant increase in liver bax protein levels was observed in the groups receiving instant coffee or caffeine as compared to the control group. These data indicate that the most pronounced hepatoprotective effect against fibrosis was observed in the groups receiving conventional coffee and 0.1% caffeine, and the greatest effects against liver carcinogenesis were detected in the groups receiving instant coffee and 0.1% caffeine. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hypertonic Saline Reduces Vascular Leakage in a Mouse Model of Severe Dengue

PubMed Central

Tan, Kar Wai; Angeli, Veronique; Moochhala, Shabbir; Ooi, Eng Eong; Alonso, Sylvie

2013-01-01

Dengue (DEN) is a mosquito-borne viral disease and represents a serious public health threat and an economical burden throughout the tropics. Dengue clinical manifestations range from mild acute febrile illness to severe DEN hemorrhagic fever/DEN shock syndrome (DHF/DSS). Currently, resuscitation with large volumes of isotonic fluid remains the gold standard of care for DEN patients who develop vascular leakage and shock. Here, we investigated the ability of small volume of hypertonic saline (HTS) suspensions to control vascular permeability in a mouse model of severe DEN associated with vascular leakage. Several HTS treatment regimens were considered and our results indicated that a single bolus of 7.5% NaCl at 4 mL per kg of body weight administered at the onset of detectable vascular leakage rapidly and significantly reduced vascular leak for several days after injection. This transient reduction of vascular leakage correlated with reduced intestine and liver damage with restoration of the hepatic functions, and resulted in delayed death of the infected animals. Mechanistically, we showed that HTS did not directly impact on the viral titers but resulted in lower immune cells counts and decreased systemic levels of soluble mediators involved in vascular permeability. In addition, we demonstrated that neutrophils do not play a critical role in DEN-associated vascular leakage and that the therapeutic effect of HTS is not mediated by its impact on the neutrophil counts. Together our data indicate that HTS treatment can transiently but rapidly reduce dengue-associated vascular leakage, and support the findings of a recent clinical trial which evaluated the efficacy of a hypertonic suspension to impact on vascular permeability in DSS children. PMID:23637867

Case Study: Polycystic Livers in a Transgenic Mouse Line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lovaglio, Jamie A.; Artwohl, James E.; Ward, Christopher J.

Three mice (2 male, 1 female; age, 5 to 16 mo) from a mouse line transgenic for keratin 14 (K14)-driven LacZ expression and on an outbred Crl:CD1(ICR) background, were identified as having distended abdomens and livers that were diffusely enlarged by numerous cysts (diameter, 0.1 to 2.0 cm). Histopathology revealed hepatic cysts lined by biliary type epithelium and mild chronic inflammation, and confirmed the absence of parasites. Among 21 related mice, 5 additional affected mice were identified via laparotomy. Breeding of these 5 mice (after 5 mo of age) did not result in any offspring; the K14 mice with olycysticmore » livers failed to reproduce. Affected male mice had degenerative testicular lesions, and their sperm was immotile. Nonpolycystic K14 control male mice bred well, had no testicular lesions, and had appropriate sperm motility. Genetic analysis did not identify an association of this phenotype with the transgene or insertion site.« less

Circadian clock-dependent and -independent posttranscriptional regulation underlies temporal mRNA accumulation in mouse liver

PubMed Central

Wang, Jingkui; Yeung, Jake; Gobet, Cédric; Sobel, Jonathan; Lück, Sarah; Molina, Nacho; Naef, Felix

2018-01-01

The mammalian circadian clock coordinates physiology with environmental cycles through the regulation of daily oscillations of gene expression. Thousands of transcripts exhibit rhythmic accumulations across mouse tissues, as determined by the balance of their synthesis and degradation. While diurnally rhythmic transcription regulation is well studied and often thought to be the main factor generating rhythmic mRNA accumulation, the extent of rhythmic posttranscriptional regulation is debated, and the kinetic parameters (e.g., half-lives), as well as the underlying regulators (e.g., mRNA-binding proteins) are relatively unexplored. Here, we developed a quantitative model for cyclic accumulations of pre-mRNA and mRNA from total RNA-seq data, and applied it to mouse liver. This allowed us to identify that about 20% of mRNA rhythms were driven by rhythmic mRNA degradation, and another 15% of mRNAs regulated by both rhythmic transcription and mRNA degradation. The method could also estimate mRNA half-lives and processing times in intact mouse liver. We then showed that, depending on mRNA half-life, rhythmic mRNA degradation can either amplify or tune phases of mRNA rhythms. By comparing mRNA rhythms in wild-type and Bmal1−/− animals, we found that the rhythmic degradation of many transcripts did not depend on a functional BMAL1. Interestingly clock-dependent and -independent degradation rhythms peaked at distinct times of day. We further predicted mRNA-binding proteins (mRBPs) that were implicated in the posttranscriptional regulation of mRNAs, either through stabilizing or destabilizing activities. Together, our results demonstrate how posttranscriptional regulation temporally shapes rhythmic mRNA accumulation in mouse liver. PMID:29432155

Anti-oxidant and anti-inflammatory effects of hydrogen-rich water alleviate ethanol-induced fatty liver in mice.

PubMed

Lin, Ching-Pin; Chuang, Wen-Chen; Lu, Fung-Jou; Chen, Chih-Yen

2017-07-21

To investigate the effects of hydrogen-rich water (HRW) treatment on prevention of ethanol (EtOH)-induced early fatty liver in mice. In vitro reduction of hydrogen peroxide by HRW was determined with a chemiluminescence system. Female mice were randomly divided into five groups: control, EtOH, EtOH + silymarin, EtOH + HRW and EtOH + silymarin + HRW. Each group was fed a Lieber-DeCarli liquid diet containing EtOH or isocaloric maltose dextrin (control diet). Silymarin was used as a positive control to compare HRW efficacy against chronic EtOH-induced hepatotoxicity. HRW was freshly prepared and given at a dosage of 1.2 mL/mouse trice daily. Blood and liver tissue were collected after chronic-binge liquid-diet feeding for 12 wk. The in vitro study showed that HRW directly scavenged hydrogen peroxide. The in vivo study showed that HRW increased expression of acyl ghrelin, which was correlated with food intake. HRW treatment significantly reduced EtOH-induced increases in serum alanine aminotransferase, aspartate aminotransferase, triglycerol and total cholesterol levels, hepatic lipid accumulation and inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6. HRW attenuated malondialdehyde level, restored glutathione depletion and increased superoxide dismutase, glutathione peroxidase and catalase activities in the liver. Moreover, HRW reduced TNF-α and IL-6 levels but increased IL-10 and IL-22 levels. HRW protects against chronic EtOH-induced liver injury, possibly by inducing acyl ghrelin to suppress the pro-inflammatory cytokines TNF-α and IL-6 and induce IL-10 and IL-22, thus activating antioxidant enzymes against oxidative stress.

Anti-oxidant and anti-inflammatory effects of hydrogen-rich water alleviate ethanol-induced fatty liver in mice

PubMed Central

Lin, Ching-Pin; Chuang, Wen-Chen; Lu, Fung-Jou; Chen, Chih-Yen

2017-01-01

AIM To investigate the effects of hydrogen-rich water (HRW) treatment on prevention of ethanol (EtOH)-induced early fatty liver in mice. METHODS In vitro reduction of hydrogen peroxide by HRW was determined with a chemiluminescence system. Female mice were randomly divided into five groups: control, EtOH, EtOH + silymarin, EtOH + HRW and EtOH + silymarin + HRW. Each group was fed a Lieber-DeCarli liquid diet containing EtOH or isocaloric maltose dextrin (control diet). Silymarin was used as a positive control to compare HRW efficacy against chronic EtOH-induced hepatotoxicity. HRW was freshly prepared and given at a dosage of 1.2 mL/mouse trice daily. Blood and liver tissue were collected after chronic-binge liquid-diet feeding for 12 wk. RESULTS The in vitro study showed that HRW directly scavenged hydrogen peroxide. The in vivo study showed that HRW increased expression of acyl ghrelin, which was correlated with food intake. HRW treatment significantly reduced EtOH-induced increases in serum alanine aminotransferase, aspartate aminotransferase, triglycerol and total cholesterol levels, hepatic lipid accumulation and inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6. HRW attenuated malondialdehyde level, restored glutathione depletion and increased superoxide dismutase, glutathione peroxidase and catalase activities in the liver. Moreover, HRW reduced TNF-α and IL-6 levels but increased IL-10 and IL-22 levels. CONCLUSION HRW protects against chronic EtOH-induced liver injury, possibly by inducing acyl ghrelin to suppress the pro-inflammatory cytokines TNF-α and IL-6 and induce IL-10 and IL-22, thus activating antioxidant enzymes against oxidative stress. PMID:28785146

Validation of a preclinical model of diethylnitrosamine-induced hepatic neoplasia in Yucatan miniature pigs

PubMed Central

Mitchell, Jennifer; Tinkey, Peggy T.; Avritscher, Rony; Van Pelt, Carolyn; Eskandari, Ghazaleh; George, Suraj Konnath; Xiao, Lianchun; Cressman, Erik; Morris, Jeffrey S.; Rashid, Asif; Kaseb, Ahmed O.; Amin, Hesham M.; Uthamanthil, Rajesh

2016-01-01

Objective The purpose of this study was to reduce time to tumor onset in a diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) swine model via partial liver embolization (PLE) and to characterize the model for use in translational research. Methods Eight Yucatan miniature pigs were injected intraperitoneally with either saline (n=2) or DEN (n=6) solution weekly for 12 weeks. Three of the DEN-treated pigs underwent PLE. Animals underwent periodic radiological evaluation, liver biopsy, and blood sampling, and full necropsy was performed at study termination (~29 months). Results All DEN-treated pigs developed hepatic adenoma and HCC. PLE accelerated the time to adenoma development but not to HCC development. Biomarker analysis results showed that IGF1 levels decreased in all DEN-treated pigs, as functional liver capacity decreased with progression of HCC. VEGF and IL-6 levels were positively correlated with disease progression. Immunohistochemical probing of HCC tissues demonstrated the expression of several important survival-promoting proteins. Conclusion To our knowledge, we are the first to demonstrate accelerated development of hepatic neoplasia in Yucatan miniature pigs. Our HCC swine model closely mimics the human condition (i.e., progressive disease stages and expression of relevant molecular markers) and is a viable translational model. PMID:27305144

Impact of myeloid-derived suppressor cell on Kupffer cells from mouse livers with hepatocellular carcinoma

PubMed Central

Lacotte, Stéphanie; Slits, Florence; Orci, Lorenzo A.; Meyer, Jeremy; Oldani, Graziano; Gonelle-Gispert, Carmen; Morel, Philippe; Toso, Christian

2016-01-01

ABSTRACT Kupffer cells represent the first line of defense against tumor cells in the liver. Myeloid-derived suppressor cells (MDSC) have recently been observed in the liver parenchyma of tumor-bearing animals. The present study investigates the function of the MDSC subsets, and their impact on Kupffer cell phenotype and function. RIL-175 mouse hepatocellular carcinoma (HCC) cells were injected into the median liver lobe of C57BL/6 mice. Three weeks later, the median lobe hosting the tumor nodule was removed, and Kupffer cells and MDSCs were sorted from the remaining liver. Mouse livers devoid of HCC served as control. Kupffer cells expressed less co-stimulatory CD86 and MHCII and more co-inhibitory CD274 molecules in HCC-bearing livers than in control livers. Corresponding to this phenotype, Kupffer cells from HCC-bearing mice were less efficient in their function as antigen-presenting cells. Three CD11b+ cell populations were identified and sorted from HCC-bearing mice. These cells had various phenotypes with different levels of MDSC-specific surface markers (Ly6Ghigh cells, Gr1high cells, and Ly6Clow cells), and may be considered as bonafide MDSCs given their suppression of antigen-specific T cell proliferation. Primary isolated Kupffer cells in co-culture with the three MDSC subsets showed a decrease in CCL2 and IL-18 secretion, and an increase in IL-10 and IL-1β secretion, and an increased expression of CD86, CD274, and MHCII. In conclusion, these data demonstrated the existence of three MDSC subsets in HCC-bearing animals. These cells altered Kupffer cell function and may decrease the migration and activation of anticancer effector cells in the liver. PMID:27999748

Dietary Broccoli Lessens Development of Fatty Liver and Liver Cancer in Mice Given Diethylnitrosamine and Fed a Western or Control Diet123

PubMed Central

Chen, Yung-Ju; Wallig, Matthew A; Jeffery, Elizabeth H

2016-01-01

Background: The high-fat and high-sugar Westernized diet that is popular worldwide is associated with increased body fat accumulation, which has been related to the development of nonalcoholic fatty liver disease (NAFLD). Without treatment, NAFLD may progress to hepatocellular carcinoma (HCC), a cancer with a high mortality rate. The consumption of broccoli in the United States has greatly increased in the last 2 decades. Epidemiologic studies show that incorporating brassica vegetables into the daily diet lowers the risk of several cancers, although, to our knowledge, this is the first study to evaluate HCC prevention through dietary broccoli. Objective: We aimed to determine the impact of dietary broccoli on hepatic lipid metabolism and the progression of NAFLD to HCC. Our hypothesis was that broccoli decreases both hepatic lipidosis and the development of HCC in a mouse model of Western diet–enhanced liver cancer. Methods: Adult 5-wk-old male B6C3F1 mice received a control diet (AIN-93M) or a Western diet (high in lard and sucrose, 19% and 31%, wt:wt, respectively), with or without freeze-dried broccoli (10%, wt:wt). Starting the following week, mice were treated once per week with diethylnitrosamine (DEN; 45 mg/kg body weight intraperitoneally at ages 6, 7, 8, 10, 11, and 12 wk). Hepatic gene expression, lipidosis, and tumor outcomes were analyzed 6 mo later, when mice were 9 mo old. Results: Mice receiving broccoli exhibited lower hepatic triglycerides (P < 0.001) and NAFLD scores (P < 0.0001), decreased plasma alanine aminotransferase (P < 0.0001), suppressed activation of hepatic CD68+ macrophages (P < 0.0001), and slowed initiation and progression of hepatic neoplasm. Hepatic Cd36 was downregulated by broccoli feeding (P = 0.006), whereas microsomal triglyceride transfer protein was upregulated (P = 0.045), supporting the finding that dietary broccoli decreased hepatic triglycerides. Conclusion: Long-term consumption of whole broccoli countered both NAFLD

Drug-induced liver injury due to antibiotics.

PubMed

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.

ERK Signaling Pathway Plays a Key Role in Baicalin Protection Against Acetaminophen-Induced Liver Injury.

PubMed

Liao, Chia-Chih; Day, Yuan-Ji; Lee, Hung-Chen; Liou, Jiin-Tarng; Chou, An-Hsun; Liu, Fu-Chao

2017-01-01

Acetaminophen (APAP) overdose causes hepatocytes necrosis and acute liver failure. Baicalin (BA), a major flavonoid of Scutellariae radix, has potent hepatoprotective properties in traditional medicine. In the present study, we investigated the protective effects of BA on a APAP-induced liver injury in a mouse model. The mice received an intraperitoneal hepatotoxic dose of APAP (300[Formula: see text]mg/kg) and after 30[Formula: see text]min, were treated with BA at concentrations of 0, 15, 30, or 60[Formula: see text]mg/kg. After 16[Formula: see text]h of treatment, the mice were sacrificed for further analysis. APAP administration significantly elevated the serum alanine transferase (ALT) enzyme levels and hepatic myeloperoxidase (MPO) activity when compared with control animals. Baicalin treatment significantly attenuated the elevation of liver ALT levels, as well as hepatic MPO activity in a dose- dependent manner (15-60[Formula: see text]mg/kg) in APAP-treated mice. The strongest beneficial effects of BA were seen at a dose of 30[Formula: see text]mg/kg. BA treatment at 30[Formula: see text]mg/kg after APAP overdose reduced elevated hepatic cytokine (TNF-[Formula: see text] and IL-6) levels, and macrophage recruitment around the area of hepatotoxicity in immunohistochemical staining. Significantly, BA treatment can also decrease hepatic phosphorylated extracellular signal-regulated kinase (ERK) expression, which is induced by APAP overdose. Our data suggests that baicalin treatment can effectively attenuate APAP-induced liver injury by down-regulating the ERK signaling pathway and its downstream effectors of inflammatory responses. These results support that baicalin is a potential hepatoprotective agent.

Fasting Induces Nuclear Factor E2-Related Factor 2 and ATP-Binding Cassette Transporters via Protein Kinase A and Sirtuin-1 in Mouse and Human

PubMed Central

Kulkarni, Supriya R.; Donepudi, Ajay C.; Xu, Jialin; Wei, Wei; Cheng, Qiuqiong C.; Driscoll, Maureen V.; Johnson, Delinda A.; Johnson, Jeffrey A.; Li, Xiaoling

2014-01-01

Abstract Aims: The purpose of this study was to determine whether 3′-5′-cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) and Sirtuin-1 (SIRT1) dependent mechanisms modulate ATP-binding Cassette (ABC) transport protein expression. ABC transport proteins (ABCC2–4) are essential for chemical elimination from hepatocytes and biliary excretion. Nuclear factor-E2 related-factor 2 (NRF2) is a transcription factor that mediates ABCC induction in response to chemical inducers and liver injury. However, a role for NRF2 in the regulation of transporter expression in nonchemical models of liver perturbation is largely undescribed. Results: Here we show that fasting increased NRF2 target gene expression through NRF2- and SIRT1–dependent mechanisms. In intact mouse liver, fasting induces NRF2 target gene expression by at least 1.5 to 5-fold. In mouse and human hepatocytes, treatment with 8-Bromoadenosine-cAMP, a cAMP analogue, increased NRF2 target gene expression and antioxidant response element activity, which was decreased by the PKA inhibitor, H-89. Moreover, fasting induced NRF2 target gene expression was decreased in liver and hepatocytes of SIRT1 liver-specific null mice and NRF2-null mice. Lastly, NRF2 and SIRT1 were recruited to MAREs and Antioxidant Response Elements (AREs) in the human ABCC2 promoter. Innovation: Oxidative stress mediated NRF2 activation is well described, yet the influence of basic metabolic processes on NRF2 activation is just emerging. Conclusion: The current data point toward a novel role of nutrient status in regulation of NRF2 activity and the antioxidant response, and indicates that cAMP/PKA and SIRT1 are upstream regulators for fasting-induced activation of the NRF2-ARE pathway. Antioxid. Redox Signal. 20, 15–30. PMID:23725046

Deficiency of cholesterol 7α‐hydroxylase in bile acid synthesis exacerbates alcohol‐induced liver injury in mice

PubMed Central

Donepudi, Ajay C.; Ferrell, Jessica M.; Boehme, Shannon; Choi, Hueng‐Sik

2017-01-01

Alcoholic fatty liver disease (AFLD) is a major risk factor for cirrhosis‐associated liver diseases. Studies demonstrate that alcohol increases serum bile acids in humans and rodents. AFLD has been linked to cholestasis, although the physiologic relevance of increased bile acids in AFLD and the underlying mechanism of increasing the bile acid pool by alcohol feeding are still unclear. In this study, we used mouse models either deficient of or overexpressing cholesterol 7α‐hydroxylase (Cyp7a1), the rate‐limiting and key regulatory enzyme in bile acid synthesis, to study the effect of alcohol drinking in liver metabolism and inflammation. Mice were challenged with chronic ethanol feeding (10 days) plus a binge dose of alcohol by oral gavage (5 g/kg body weight). Alcohol feeding reduced bile acid synthesis gene expression but increased the bile acid pool size, hepatic triglycerides and cholesterol, and inflammation and injury in wild‐type mice and aggravated liver inflammation and injury in Cyp7a1‐deficient mice. Interestingly, alcohol‐induced hepatic inflammation and injury were ameliorated in Cyp7a1 transgenic mice. Conclusion: Alcohol feeding alters hepatic bile acid and cholesterol metabolism to cause liver inflammation and injury, while maintenance of bile acid and cholesterol homeostasis protect against alcohol‐induced hepatic inflammation and injury. Our findings indicate that CYP7A1 plays a key role in protection against alcohol‐induced steatohepatitis. (Hepatology Communications 2018;2:99–112) PMID:29404516

Role of YAP activation in nuclear receptor CAR-mediated proliferation of mouse hepatocytes.

PubMed

Abe, Taiki; Amaike, Yuto; Shizu, Ryota; Takahashi, Miki; Kano, Makoto; Hosaka, Takuomi; Sasaki, Takamitsu; Kodama, Susumu; Matsuzawa, Atsushi; Yoshinari, Kouichi

2018-06-08

Constitutive androstane receptor (CAR) is a xenobiotic-responsive nuclear receptor that is highly expressed in the liver. CAR activation induces hepatocyte proliferation and hepatocarcinogenesis in rodents, but the mechanisms remain unclear. In this study, we investigated the association of CAR-dependent cell proliferation with Yes-associated protein (YAP), which is a transcriptional cofactor controlling organ size and cell growth through the interaction with various transcriptional factors including TEAD. In mouse livers, TCPOBOP (a mouse CAR activator) treatment increased the nuclear YAP accumulation and mRNA levels of YAP target genes as well as cell-cycle related genes along with liver hypertrophy and verteporfin (an inhibitor of YAP/TEAD interaction) cotreatment tended to attenuate them. Furthermore, in cell-based reporter gene assays, CAR activation enhanced the YAP/TEAD-dependent transcription. To investigate the role of YAP/TEAD activation in the CAR-dependent hepatocyte proliferation, we sought to establish an in vitro system completely reproducing CAR-dependent cell proliferation. Since CAR was only slightly expressed in cultured mouse primary hepatocytes compared to mouse livers and no proliferation was observed after treatment with TCPOBOP, we overexpressed CAR using mouse CAR expressing adenovirus (Ad-mCAR-V5) in mouse primary hepatocytes. Ad-mCAR-V5 infection and TCPOBOP treatment induced hepatocyte proliferation. Similar results were obtained with immortalized normal mouse hepatocytes as well. In the established in vitro system, CAR-dependent proliferation was strongly inhibited by Yap knockdown and completely abolished by verteporfin treatment. Our present results obtained in in vivo and in vitro experiments suggest that YAP/TEAD activation plays key roles in CAR-dependent proliferation of murine hepatocytes.

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

PubMed

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.

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

PubMed Central

Jing, Jing; Teschke, Rolf

2017-01-01

Abstract 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. PMID:29577033

The Protective Effect of Glycyrrhetinic Acid on Carbon Tetrachloride-Induced Chronic Liver Fibrosis in Mice via Upregulation of Nrf2

PubMed Central

Chen, Shaoru; Zou, Liyi; Li, Li; Wu, Tie

2013-01-01

This study was designed to investigate the potentially protective effects of glycyrrhetinic acid (GA) and the role of transcription factor nuclear factor-erythroid 2(NF-E2)-related factor 2 (Nrf2) signaling in the regulation of Carbon Tetrachloride (CCl4)-induced chronic liver fibrosis in mice. The potentially protective effects of GA on CCl4-induced chronic liver fibrosis in mice were depicted histologically and biochemically. Firstly, histopathological changes including regenerative nodules, inflammatory cell infiltration and fibrosis were induced by CCl4.Then, CCl4 administration caused a marked increase in the levels of serum aminotransferases (GOT, GPT), serum monoamine oxidase (MAO) and lipid peroxidation (MDA) as well as MAO in the mice liver homogenates. Also, decreased nuclear Nrf2 expression, mRNA levels of its target genes such as superoxide dismutase 3 (SOD3), catalase (CAT), glutathione peroxidase 2 (GPX2), and activity of cellular antioxidant enzymes were found after CCl4 exposure. All of these phenotypes were markedly reversed by the treatment of the mice with GA. In addition, GA exhibited the antioxidant effects in vitro by on FeCl2-ascorbate induced lipid peroxidation in mouse liver homogenates, and on DPPH scavenging activity. Taken together, these results suggested that GA can protect the liver from oxidative stress in mice, presumably through activating the nuclear translocation of Nrf2, enhancing the expression of its target genes and increasing the activity of the antioxidant enzymes. Therefore, GA may be an effective hepatoprotective agent and viable candidate for treating liver fibrosis and other oxidative stress-related diseases. PMID:23341968

Activation of mouse liver natural killer cells and NK1.1(+) T cells by bacterial superantigen-primed Kupffer cells.

PubMed

Dobashi, H; Seki, S; Habu, Y; Ohkawa, T; Takeshita, S; Hiraide, H; Sekine, I

1999-08-01

Although bacterial superantigens have been well characterized as potent stimulators of T cells, their role in natural killer (NK)-type cells remains largely unknown. In the present study, we examined the effect of bacterial superantigens on mouse liver NK cells and NK1.1 Ag(+) (NK1(+)) T cells. C57BL/6 mice were intravenously injected with staphylococcal enterotoxin B (SEB) or streptococcal pyrogenic exotoxin A (SPE-A), and mononuclear cells (MNC) of various organs were obtained from mice 4 hours after being injected with superantigen. MNC were cultured for 48 hours, and interferon gamma (IFN-gamma) levels of supernatants were measured. The antitumor cytotoxicities of the liver and spleen MNC were also evaluated 24 hours after the mice were injected with superantigen. Liver MNC produced more IFN-gamma than did splenocytes, and peripheral blood and lung MNC did not produce any detectable IFN-gamma. In addition, liver MNC acquired a potent antitumor cytotoxicity by the SEB injection, and both NK cells and NK1(+)T cells but not cluster of differentiation (CD)8(+) T cells were responsible for the cytotoxicity as demonstrated by either in vivo or in vitro cell depletion experiments, and the NK-type cells were partly responsible for the increased serum IFN-gamma. Activation of liver NK-type cells was also supported by the fact that liver NK cells proportionally increased and NK1(+) T cells augmented their CD11a expressions after SEB injection. The pretreatment of mice with anti-IFN-gamma Ab and/or with anti-interleukin-12 (IL-12) Ab diminished the SEB-induced cytotoxicity of liver MNC. Furthermore, the in vivo depletion of Kupffer cells decreased the SEB-induced cytotoxicity of liver MNC. Consistent with these results, liver MNC stimulated with superantigens in the presence of Kupffer cells in vitro produced a greater amount of IFN-gamma than did the liver MNC without Kupffer cells or splenocytes. Our results suggest that bacterial superantigen-primed Kupffer cells

Liver microRNA profile of induced allograft tolerance

PubMed Central

Vitalone, Matthew James; Wai, Liang; Fujiki, Masato; Lau, Audrey H.; Littau, Erik; Esquivel, Carlos; Martinez, Olivia M.; Krams, Sheri M.

2016-01-01

Introduction Although the liver is less immunogenic than other solid organs, most liver transplant recipients receive lifelong immunosuppression. In both experimental models and clinical transplantation, total Lymphoid Irradiation (TLI) has been shown to induce allograft tolerance. Our goal was to identify the microRNAs (miRNAs) expressed in tolerant liver allograft recipients in an experimental model of TLI-induced tolerance. Methods To identify the miRNAs associated with TLI-induced tolerance we examined syngeneic recipients (Lewis→Lewis) and allogeneic recipients (DA→Lewis) of orthotropic liver transplants that received post-transplant TLI, allogeneic recipients that were not treated post-transplantation and experienced acute rejection, and native DA livers. QPCR miRNA array cards were used to profile liver grafts. Results We identified 12 miRNAs that were specifically and significantly increased during acute rejection. In early tolerance, 33 miRNAs were altered compared to syngeneic livers, with 80% of the miRNAs increased. In established tolerance 42 miRNAs were altered. In addition, miR-142-5p and miR-181a demonstrated increased expression in tolerant livers (both early and established tolerance) as compared to syngeneic livers. A principal component analysis of all miRNAs assayed, demonstrated a profile in established tolerance that was closely related to that seen in syngeneic livers. Conclusions The miRNA profile of established tolerant allografts is very similar to syngeneic grafts suggesting tolerance may be a return to an immunological state of quiescence. PMID:26950716

Screening for the protective effect target of deproteinized extract of calf blood and its mechanisms in mice with CCl4-induced acute liver injury.

PubMed

Xu, Guangyu; Han, Xiao; Yuan, Guangxin; An, Liping; Du, Peige

2017-01-01

Liver injury is a common pathological basis of various liver diseases, and long-term liver injury is often an important initiation factor leading to liver fibrosis and even liver cirrhosis and hepatocellular carcinoma (HCC). It has been reported that deproteinized extract of calf blood (DECB) can inhibit the replication of hepatitis B virus and confers a protective effect on the liver after traumatic liver injury. However, few studies on the regulatory factors and mechanisms of DECB have been reported. In this current study, an acute mouse liver injury model was established with carbon tetrachloride (CCl4). The differentially expressed genes and related cell signal transduction pathways were screened using mRNA expression microarray. STEM software V1.3.6 was used for clustering gene functions, and the DAVID and KEGG databases were applied for the analysis. A total of 1355 differentially expressed genes were selected, among which nine were validated by RT-qPCR. The results showed that the Fas, IL1b, Pik3r1, Pik3r5, Traf2, Traf2, Csf2rb2, Map3k14, Pik3cd and Ppp3cc genes were involved in the regulation of DECB in an acute mouse liver injury model. Targets of the protective effects of DECB and its related mechanisms were found in mice with acute liver injury induced by carbon tetrachloride, which may provide an important theoretical basis for further DECB research.

IDENTIFICATION OF EARLY MOLECULAR EVENTS AFTER PEROXISOME PROLIFERATOR EXPOSURE IN THE RODENT LIVER

EPA Science Inventory

Peroxisome proliferators (PP) are a large class of structurally diverse chemicals that mediate their effects in the liver mainly through the PP-activated receptor α(PPARα). Development of PP induced hepatocarcinogenesis in mouse liver is known to be dependent on PPARα but do...

Protective effect of human serum amyloid P on CCl4-induced acute liver injury in mice.

PubMed

Cong, Min; Zhao, Weihua; Liu, Tianhui; Wang, Ping; Fan, Xu; Zhai, Qingling; Bao, Xiaoli; Zhang, Dong; You, Hong; Kisseleva, Tatiana; Brenner, David A; Jia, Jidong; Zhuang, Hui

2017-08-01

Human serum amyloid P (hSAP), a member of the pentraxin family, inhibits the activation of fibrocytes in culture and inhibits experimental renal, lung, skin and cardiac fibrosis. As hepatic inflammation is one of the causes of liver fibrosis, in the present study, we investigated the hepatoprotective effects of hSAP against carbon tetrachloride (CCl4)-induced liver injury. Our data indicated that hSAP attenuated hepatic histopathological abnormalities and significantly decreased inflammatory cell infiltration and pro-inflammatory factor expression. Moreover, CCl4-induced apoptosis in the mouse liver was inhibited by hSAP, as measured by terminal-deoxynucleotidyl transferase mediated nick-end labeling (TUNEL) assay and cleaved caspase-3 expression. hSAP significantly restored the expression of B cell lymphoma/leukemia (Bcl)-2 and suppressed the expression of Bcl-2-associated X protein (Bax) in vivo. The number of hepatocytes in early apoptosis stained with Annexin V was significantly reduced by 28-30% in the hSAP treatment group compared with the CCl4 group, and the expression of Bcl-2 was increased, whereas the expression of Bax and cleaved caspase-3 were significantly inhibited in the hSAP pre-treatment group compared with the CCl4 group. hSAP administration also inhibited the migration and activation of hepatic stellate cells (HSCs) in CCl4-injured liver and suppressed the activation of isolated primary HSCs induced by transforming growth factor (TGF)-β1 in vitro. Collectively, these findings suggest that hSAP exerts a protective effect againts CCl4-induced hepatic injury by suppressing the inflammatory response and hepatocyte apoptosis, potentially by inhibiting HSC activation.

Protective effect of human serum amyloid P on CCl4-induced acute liver injury in mice

PubMed Central

Cong, Min; Zhao, Weihua; Liu, Tianhui; Wang, Ping; Fan, Xu; Zhai, Qingling; Bao, Xiaoli; Zhang, Dong; You, Hong; Kisseleva, Tatiana; Brenner, David A.; Jia, Jidong; Zhuang, Hui

2017-01-01

Human serum amyloid P (hSAP), a member of the pentraxin family, inhibits the activation of fibrocytes in culture and inhibits experimental renal, lung, skin and cardiac fibrosis. As hepatic inflammation is one of the causes of liver fibrosis, in the present study, we investigated the hepatoprotective effects of hSAP against carbon tetrachloride (CCl4)-induced liver injury. Our data indicated that hSAP attenuated hepatic histopathological abnormalities and significantly decreased inflammatory cell infiltration and pro-inflammatory factor expression. Moreover, CCl4-induced apoptosis in the mouse liver was inhibited by hSAP, as measured by terminal-deoxynucleotidyl transferase mediated nick-end labeling (TUNEL) assay and cleaved caspase-3 expression. hSAP significantly restored the expression of B cell lymphoma/leukemia (Bcl)-2 and suppressed the expression of Bcl-2-associated X protein (Bax) in vivo. The number of hepatocytes in early apoptosis stained with Annexin V was significantly reduced by 28–30% in the hSAP treatment group compared with the CCl4 group, and the expression of Bcl-2 was increased, whereas the expression of Bax and cleaved caspase-3 were significantly inhibited in the hSAP pre-treatment group compared with the CCl4 group. hSAP administration also inhibited the migration and activation of hepatic stellate cells (HSCs) in CCl4-injured liver and suppressed the activation of isolated primary HSCs induced by transforming growth factor (TGF)-β1 in vitro. Collectively, these findings suggest that hSAP exerts a protective effect againts CCl4-induced hepatic injury by suppressing the inflammatory response and hepatocyte apoptosis, potentially by inhibiting HSC activation. PMID:28627620

NMR-based Metabolomics Analysis of Liver from C57BL/6 Mouse Exposed to Ionizing Radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Xiongjie; Hu, Mary; Zhang, Xu

The health effects of exposing to ionizing radiation are attracting great interest in the space exploration community and patients considering radiotherapy. However, the impact to metabolism after exposure to high dose radiation has not yet been clearly defined in livers. In the present study, 1H nuclear magnetic resonance (NMR) based metabolomics combined with multivariate data analysis are applied to study the changes of metabolism in the liver of C57BL/6 mouse after whole body exposure to either gamma (3.0 and 7.8 Gy) or proton (3.0 Gy) radiation. Principal component analysis (PCA) and orthogonal projection to latent structures analysis (OPLS) are employedmore » for classification and identification of potential biomarkers associated with gamma and proton irradiation. The results show that the radiation exposed groups can be well separated from the control group. At the same radiation dosage, the group exposed to proton radiation is well separated from the group exposed to gamma radiation, indicating different radiation sources induce different alterations based on metabolic profiling. Common to both gamma and proton radiation at the high radiation doses studied in this work, compared with the control groups the concentrations of choline, O-phosphocholine and trimethylamine N-oxide are decreased statistically, while those of glutamine, glutathione, malate, creatinine, phosphate, betaine and 4-hydroxyphenylacetate are statistically and significantly elevated after exposure to radiation. Since these altered metabolites are associated with multiple biological pathways, the changes suggest that the exposure to radiation induce abnormality in multiple biological pathways. In particular, metabolites such as 4-hydroxyphenylacetate, betaine, glutamine, choline and trimethylamine N-oxide may be good candidates of pre-diagnose biomarkers for ionizing radiation in liver.« less

Sonodynamic action of pyropheophorbide-a methyl ester induces mitochondrial damage in liver cancer cells.

PubMed

Xu, Jing; Xia, Xinshu; Leung, Albert Wingnang; Xiang, Junyan; Jiang, Yuan; Yu, Heping; Bai, Dingqun; Li, Xiaohong; Xu, Chuanshan

2011-05-01

Sonodynamic therapy with pyropheophorbide-a methyl ester (MPPa) presents a promising aspect in treating liver cancer. The present study aims to investigate the mitochondrial damage of liver cancer cells induced by MPPa-mediated sonodynamic action. Mouse hepatoma cell line H(22) cells were incubated with MPPa (2 μM) for 20 h and then exposed to ultrasound with an intensity of 0.97 W/cm(2) for 8 s. Cytotoxicity was investigated 24h after sonodynamic action using MTT assay and light microscopy. Mitochondrial membrane potential (ΔΨm) was analyzed using flow cytometry with rhodamine 123 staining and ultrastructural changes were observed using transmission electron microscopy (TEM). The cytotoxicity of MPPa-mediated SDT on H(22) cell line was 73.00±3.42%, greater than ultrasound treatment alone (28.12±5.19%) significantly while MPPa treatment alone had no significant effect on H(22) cells. Moreover, after MPPa-mediated SDT cancer cells showed swollen mitochondria under TEM and a significant collapse of mitochondrial membrane potential. Our findings demonstrated that MPPa-mediated SDT could remarkably induce cell death of H(22) cells, and highlighted that mitochondrial damage might be an important cause of cell death induced by MPPa-mediated SDT. Copyright © 2010 Elsevier B.V. All rights reserved.

Liver metabolomics study reveals protective function of Phyllanthus urinaria against CCl4-induced liver injury.

PubMed

Guo, Qing; Zhang, Qian-Qian; Chen, Jia-Qing; Zhang, Wei; Qiu, Hong-Cong; Zhang, Zun-Jian; Liu, Bu-Ming; Xu, Feng-Guo

2017-07-01

Phyllanthus Urinaria L. (PUL) is a traditional Chinese medicine used to treat hepatic and renal disorders. However, the mechanism of its hepatoprotective action is not fully understood. In the present study, blood biochemical indexes and liver histopathological changes were used to estimate the extent of hepatic injury. GC/MS and LC/MS-based untargeted metabolomics were used in combination to characterize the potential biomarkers associated with the protective activity of PUL against CCl 4 -induced liver injury in rats. PUL treatment could reverse the increase in ALT, AST and ALP induced by CCl 4 and attenuate the pathological changes in rat liver. Significant changes in liver metabolic profiling were observed in PUL-treated group compared with liver injury model group. Seventeen biomarkers related to the hepatoprotective effects of PUL against CCl 4 -induced liver injury were screened out using nonparametric test and Pearson's correlation analysis (OPLS-DA). The results suggested that the potential hepatoprotective effects of PUL in attenuating CCl 4 -induced hepatotoxicity could be partially attributed to regulating L-carnitine, taurocholic acid, and amino acids metabolism, which may become promising targets for treatment of liver toxicity. In conclusion, this study provides new insights into the mechanism of the hepatoprotection of Phyllanthus Urinaria. Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Interleukins-17 and 27 promote liver regeneration by sequentially inducing progenitor cell expansion and differentiation.

PubMed

Guillot, Adrien; Gasmi, Imène; Brouillet, Arthur; Ait-Ahmed, Yeni; Calderaro, Julien; Ruiz, Isaac; Gao, Bin; Lotersztajn, Sophie; Pawlotsky, Jean-Michel; Lafdil, Fouad

2018-03-01

Liver progenitor cells (LPCs)/ductular reactions (DRs) are associated with inflammation and implicated in the pathogenesis of chronic liver diseases. However, how inflammation regulates LPCs/DRs remains largely unknown. Identification of inflammatory processes that involve LPC activation and expansion represent a key step in understanding the pathogenesis of liver diseases. In the current study, we found that diverse types of chronic liver diseases are associated with elevation of infiltrated interleukin (IL)-17-positive (+) cells and cytokeratin 19 (CK19) + LPCs, and both cell types colocalized and their numbers positively correlated with each other. The role of IL-17 in the induction of LPCs was examined in a mouse model fed a choline-deficient and ethionine-supplemented (CDE) diet. Feeding of wild-type mice with the CDE diet markedly elevated CK19 + Ki67 + proliferating LPCs and hepatic inflammation. Disruption of the IL-17 gene or IL-27 receptor, alpha subunit (WSX-1) gene abolished CDE diet-induced LPC expansion and inflammation. In vitro treatment with IL-17 promoted proliferation of bipotential murine oval liver cells (a liver progenitor cell line) and markedly up-regulated IL-27 expression in macrophages. Treatment with IL-27 favored the differentiation of bipotential murine oval liver cells and freshly isolated LPCs into hepatocytes. Conclusion : The current data provide evidence for a collaborative role between IL-17 and IL-27 in promoting LPC expansion and differentiation, respectively, thereby contributing to liver regeneration. ( Hepatology Communications 2018;2:329-343).

Acetaminophen-induced acute liver injury in HCV transgenic mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uehara, Takeki; Kosyk, Oksana; Jeannot, Emmanuelle

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 wildmore » 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.« less

Evaluation of the Role of Peroxisome Proliferator-Activated Receptor α (PPARα) in Mouse Liver Tumor Induction by Trichloroethylene and Metabolites

EPA Science Inventory

Trichloroethylene (TCE) is an industrial solvent and a widespread environmental contaminant. Induction of liver cancer in mice by TCE is thought to be mediated by two metabolites, dichloroacetate (DCA) and trichloroacetate (TCA), both of which are themselves mouse liver carcinoge...

Diet-induced non-alcoholic fatty liver disease affects expression of major cytochrome P450 genes in a mouse model.

PubMed

Chiba, Tsuyoshi; Noji, Keiko; Shinozaki, Shohei; Suzuki, Sachina; Umegaki, Keizo; Shimokado, Kentaro

2016-12-01

Non-alcoholic fatty liver disease (NAFLD) is associated with impaired liver function, and resveratrol could suppress NAFLD progression. This study examined the effects of NAFLD on the expression of major cytochrome P450 (CYP) subtypes in the liver and whether the expression could be attenuated by resveratrol. C57BL/6 mice (male, 10 weeks of age) were fed a high-fat and high-sucrose (HFHS) diet to induce NAFLD. Major Cyp subtype mRNA expression in the liver was measured by real-time RT-PCR. Body and liver weights at 4 and 12 weeks were significantly higher in mice fed the HFHS diet compared with control. The HFHS diet significantly increased the accumulation of cholesterol and triglycerides at 12 weeks. Under this condition, the HFHS diet increased the expression of Cyp1a2 and decreased that of Cyp3a11 at 1 week and thereafter. On the other hand, Cyp1a1, 2b10 and 2c29 mRNA expression levels in the liver were significantly increased at 12 weeks only. Resveratrol (0.05% (w/w) in diet) slightly suppressed lipid accumulation in the liver, but failed to recover impaired Cyp gene expression levels in NAFLD. Drug metabolism may be impaired in NAFLD, and each Cyp subtype is regulated in a different manner. © 2016 Royal Pharmaceutical Society.

Homozygous carnitine palmitoyltransferase 1a (liver isoform) deficiency is lethal in the mouse.

PubMed

Nyman, Lara R; Cox, Keith B; Hoppel, Charles L; Kerner, Janos; Barnoski, Barry L; Hamm, Doug A; Tian, Liqun; Schoeb, Trenton R; Wood, Philip A

2005-01-01

To better understand carnitine palmitoyltransferase 1a (liver isoform, gene=Cpt-1a, protein=CPT-1a) deficiency in human disease, we developed a gene knockout mouse model. We used a replacement gene targeting strategy in ES cells that resulted in the deletion of exons 11-18, thus producing a null allele. Homozygous deficient mice (CPT-1a -/-) were not viable. There were no CPT-1a -/- pups, embryos or fetuses detected from day 10 of gestation to term. FISH analysis demonstrated targeting vector recombination at the expected single locus on chromosome 19. The inheritance pattern from heterozygous matings was skewed in both C57BL/6NTac, 129S6/SvEvTac (B6;129 mixed) and 129S6/SvEvTac (129 coisogenic) genetic backgrounds biased toward CPT-1a +/- mice (>80%). There was no sex preference with regard to germ-line transmission of the mutant allele. CPT-1a +/- mice had decreased Cpt-1a mRNA expression in liver, heart, brain, testis, kidney, and white fat. This resulted in 54.7% CPT-1 activity in liver from CPT-1a +/- males but no significant difference in females as compared to CPT-1a +/+ controls. CPT-1a +/- mice showed no fatty change in liver and were cold tolerant. Fasting free fatty acid concentrations were significantly elevated, while blood glucose concentrations were significantly lower in 6-week-old CPT-1a +/- mice compared to controls. Although the homozygous mutants were not viable, we did find some aspects of haploinsufficiency in the CPT-1a +/- mutants, which will make them an important mouse model for studying the role of CPT-1a in human disease.

Character and temporal evolution of apoptosis in acetaminophen-induced acute liver failure*.

PubMed

Possamai, Lucia A; McPhail, Mark J W; Quaglia, Alberto; Zingarelli, Valentina; Abeles, R Daniel; Tidswell, Robert; Puthucheary, Zudin; Rawal, Jakirty; Karvellas, Constantine J; Leslie, Elaine M; Hughes, Robin D; Ma, Yun; Jassem, Wayel; Shawcross, Debbie L; Bernal, William; Dharwan, Anil; Heaton, Nigel D; Thursz, Mark; Wendon, Julia A; Mitry, Ragai R; Antoniades, Charalambos G

2013-11-01

To evaluate the role of hepatocellular and extrahepatic apoptosis during the evolution of acetaminophen-induced acute liver failure. A prospective observational study in two tertiary liver transplant units. Eighty-eight patients with acetaminophen-induced acute liver failure were recruited. Control groups included patients with nonacetaminophen-induced acute liver failure (n = 13), nonhepatic multiple organ failure (n = 28), chronic liver disease (n = 19), and healthy controls (n = 11). Total and caspase-cleaved cytokeratin-18 (M65 and M30) measured at admission and sequentially on days 3, 7, and 10 following admission. Levels were also determined from hepatic vein, portal vein, and systemic arterial blood in seven patients undergoing transplantation. Protein arrays of liver homogenates from patients with acetaminophen-induced acute liver failure were assessed for apoptosis-associated proteins, and histological assessment of liver tissue was performed. Admission M30 levels were significantly elevated in acetaminophen-induced acute liver failure and non-acetaminophen induced acute liver failure patients compared with multiple organ failure, chronic liver disease, and healthy controls. Admission M30 levels correlated with outcome with area under receiver operating characteristic of 0.755 (0.639-0.885, p < 0.001). Peak levels in patients with acute liver failure were seen at admission then fell significantly but did not normalize over 10 days. A negative gradient of M30 from the portal to hepatic vein was demonstrated in patients with acetaminophen-induced acute liver failure (p = 0.042) at the time of liver transplant. Analysis of protein array data demonstrated lower apoptosis-associated protein and higher catalase concentrations in acetaminophen-induced acute liver failure compared with controls (p < 0.05). Explant histological analysis revealed evidence of cellular proliferation with an absence of histological evidence of apoptosis. Hepatocellular apoptosis occurs

Clinical data and characterization of the liver conditional mouse model exclude neoplasia as a non-neurological manifestation associated with Friedreich’s ataxia

PubMed Central

Martelli, Alain; Friedman, Lisa S.; Reutenauer, Laurence; Messaddeq, Nadia; Perlman, Susan L.; Lynch, David R.; Fedosov, Kathrin; Schulz, Jörg B.; Pandolfo, Massimo; Puccio, Hélène

2012-01-01

SUMMARY Friedreich’s ataxia (FRDA) is the most common hereditary ataxia in the caucasian population and is characterized by a mixed spinocerebellar and sensory ataxia, hypertrophic cardiomyopathy and increased incidence of diabetes. FRDA is caused by impaired expression of the FXN gene coding for the mitochondrial protein frataxin. During the past ten years, the development of mouse models of FRDA has allowed better understanding of the pathophysiology of the disease. Among the mouse models of FRDA, the liver conditional mouse model pointed to a tumor suppressor activity of frataxin leading to the hypothesis that individuals with FRDA might be predisposed to cancer. In the present work, we investigated the presence and the incidence of neoplasia in the largest FRDA patient cohorts from the USA, Australia and Europe. As no predisposition to cancer could be observed in both cohorts, we revisited the phenotype of the liver conditional mouse model. Our results show that frataxin-deficient livers developed early mitochondriopathy, iron-sulfur cluster deficits and intramitochondrial dense deposits, classical hallmarks observed in frataxin-deficient tissues and cells. With age, a minority of mice developed structures similar to the ones previously associated with tumor formation. However, these peripheral structures contained dying, frataxin-deficient hepatocytes, whereas the inner liver structure was composed of a pool of frataxin-positive cells, due to inefficient Cre-mediated recombination of the Fxn gene, that contributed to regeneration of a functional liver. Together, our data demonstrate that frataxin deficiency and tumorigenesis are not associated. PMID:22736457

A review of drug-induced liver injury databases.

PubMed

Luo, Guangwen; Shen, Yiting; Yang, Lizhu; Lu, Aiping; Xiang, Zheng

2017-09-01

Drug-induced liver injuries have been a major focus of current research in drug development, and are also one of the major reasons for the failure and withdrawal of drugs in development. Drug-induced liver injuries have been systematically recorded in many public databases, which have become valuable resources in this field. In this study, we provide an overview of these databases, including the liver injury-specific databases LiverTox, LTKB, Open TG-GATEs, LTMap and Hepatox, and the general databases, T3DB, DrugBank, DITOP, DART, CTD and HSDB. The features and limitations of these databases are summarized and discussed in detail. Apart from their powerful functions, we believe that these databases can be improved in several ways: by providing the data about the molecular targets involved in liver toxicity, by incorporating information regarding liver injuries caused by drug interactions, and by regularly updating the data.

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

PubMed

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.

Myeloid Notch1 deficiency activates the RhoA/ROCK pathway and aggravates hepatocellular damage in mouse ischemic livers.

PubMed

Lu, Ling; Yue, Shi; Jiang, Longfeng; Li, Changyong; Zhu, Qiang; Ke, Michael; Lu, Hao; Wang, Xuehao; Busuttil, Ronald W; Ying, Qi-Long; Kupiec-Weglinski, Jerzy W; Ke, Bibo

2018-03-01

Notch signaling plays an emerging role in the regulation of immune cell development and function during inflammatory response. Activation of the ras homolog gene family member A/Rho-associated protein kinase (ROCK) pathway promotes leukocyte accumulation in tissue injury. However, it remains unknown whether Notch signaling regulates ras homolog gene family member A/ROCK-mediated immune responses in liver ischemia and reperfusion (IR) injury. This study investigated intracellular signaling pathways regulated by Notch receptors in the IR-stressed liver and in vitro. In a mouse model of IR-induced liver inflammatory injury, we found that mice with myeloid-specific Notch1 knockout showed aggravated hepatocellular damage, with increased serum alanine aminotransferase levels, hepatocellular apoptosis, macrophage/neutrophil trafficking, and proinflammatory mediators compared to Notch1-proficient controls. Unlike in the controls, myeloid Notch1 ablation diminished hairy and enhancer of split-1 (Hes1) and augmented c-Jun N-terminal kinase (JNK)/stress-activated protein kinase-associated protein 1 (JSAP1), JNK, ROCK1, and phosphatase and tensin homolog (PTEN) activation in ischemic livers. Disruption of JSAP1 in myeloid-specific Notch1 knockout livers improved hepatocellular function and reduced JNK, ROCK1, PTEN, and toll-like receptor 4 activation. Moreover, ROCK1 knockdown inhibited PTEN and promoted Akt, leading to depressed toll-like receptor 4. In parallel in vitro studies, transfection of lentivirus-expressing Notch1 intracellular domain promoted Hes1 and inhibited JSAP1 in lipopolysaccharide-stimulated bone marrow-derived macrophages. Hes1 deletion enhanced JSAP1/JNK activation, whereas clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9-mediated JSAP1 knockout diminished ROCK1/PTEN and toll-like receptor 4 signaling. Myeloid Notch1 deficiency activates the ras homolog gene family member A/ROCK pathway and exacerbates hepatocellular

Failure of catalase to protect against aflatoxin B{sub 1}-induced mouse lung tumorigenicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guindon, Katherine A.; Foley, Julie F.; Maronpot, Robert R.

The carcinogenic mycotoxin aflatoxin B{sub 1} (AFB{sub 1}) induces 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation in mouse lung, an effect that can be prevented by treatment with polyethylene glycol-conjugated catalase (PEG-CAT). G {yields} T transversion mutation in K-ras, an early event in AFB{sub 1}-induced mouse lung carcinogenesis, is thought to result from AFB{sub 1}-8,9-exo-epoxide binding to DNA to form AFB{sub 1}-N{sup 7}-guanine, but may also result from formation of 8-OHdG. Therefore, oxidative DNA damage may be important in AFB{sub 1} carcinogenicity. The objective of this study was to determine whether PEG-CAT would prevent AFB{sub 1} tumorigenicity. Mouse lung tumorigenesis was assessed following treatmentmore » of female A/J mice with 300 kU/kg PEG-CAT ip and/or 50 mg/kg AFB{sub 1}. Mice were killed 7 months post-treatment and tumors greater than 1 mm in diameter were excised. Unexpectedly, the mean number of tumors per mouse in the PEG-CAT + AFB{sub 1} group (8.81 {+-} 3.64, n = 47) was greater than that of the group treated with AFB{sub 1} alone (7.05 {+-} 3.45, n = 42) (P < 0.05). The tumors obtained from mice treated with PEG-CAT + AFB{sub 1} were larger than those from mice treated with AFB{sub 1} alone (P < 0.05). There was no difference in K-ras exon 1 mutation spectrum or in the histological diagnosis of tumors between AFB{sub 1} and PEG-CAT + AFB{sub 1} groups (P > 0.05). In vitro incubation with mouse liver catalase (CAT) resulted in conversion of [{sup 3}H]AFB{sub 1} into a DNA-binding species, a possible explanation for the results observed in vivo. These results demonstrate that PEG-CAT is not protective against AFB{sub 1} carcinogenicity in mouse lung despite preventing DNA oxidation.« less

Chemically-induced mouse lung tumors: applications to ...

EPA Pesticide Factsheets

A state-of-the-science workshop on chemically-induced mouse lung tumors was conducted by U.S. Environmental Protection Agency to discuss issues related to the use of mouse lung tumor data in human health assessments. Naphthalene, styrene, and ethylbenzene were chosen for the analysis due to the commonality of mouse lung tumors in all these three environmental chemicals. The goals of the workshop were to: identify the evidence, from multiple scientific disciplines, regarding formation of chemically-induced lung tumors in mice; discuss analysis and interpretation of the evidence; discuss how such evidence informs human health assessments; and identify commonalities, linkages, or differences between the evidence from various disciplines and across the chemicals. Evidence informing the association between occupational exposure to styrene, ethylbenzene, or naphthalene and lung cancer; comparative biology of mouse lung tumors, associated pathologic effects, issues related to tissue and species concordance; mode of action analysis and biological mechanisms including pharmacokinetics and pharmacodynamics; and evidence from cellular, genetic and molecular toxicity was discussed. In summary, although consensus was not sought, the panelists agreed that data showing mouse lung tumors with chemical exposures can be relevant for human health risk evaluation on an individual chemical basis. Key data gaps were identified that would assist in further understanding the mechanism

Chemically-induced Mouse Lung Tumors: Applications to ...

EPA Pesticide Factsheets

A state-of-the-science workshop on chemically-induced mouse lung tumors was conducted by U.S. Environmental Protection Agency to better understand the mouse lung tumor data’s role in human health assessments. Three environmental chemicals - naphthalene, styrene, and ethylbenzene were chosen for the analysis due to the commonality of mouse lung tumors in all three chemicals. The goals of the workshop were to: identify the evidence, from multiple scientific disciplines, regarding formation of chemically-induced lung tumors in mice; discuss analysis and interpretation of the evidence; discuss how such evidence informs human health assessments; and identify commonalities, linkages, or differences between the evidence from various disciplines and across the chemicals. Evidence informing the association between occupational exposure to styrene, ethylbenzene, or naphthalene and lung cancer; comparative biology of mouse lung tumors, associated pathologic effects, issues related to tissue and species concordance; mode of action analysis and biological mechanisms including pharmacokinetics and pharmacodynamics; and evidence from cellular, genetic and molecular toxicity was discussed. In summary, although consensus was not sought, the panelists agreed that available mouse lung tumor data should be considered for human health risk evaluation on an individual chemical basis. Key data gaps were identified that would assist in further understanding the mechanism and relevan

Oligonol improves memory and cognition under an amyloid β(25-35)-induced Alzheimer's mouse model.

PubMed

Choi, Yoon Young; Maeda, Takahiro; Fujii, Hajime; Yokozawa, Takako; Kim, Hyun Young; Cho, Eun Ju; Shibamoto, Takayuki

2014-07-01

Alzheimer's disease is an age-dependent progressive neurodegenerative disorder that results in impairments of memory and cognitive function. It is hypothesized that oligonol has ameliorative effects on memory impairment and reduced cognitive functions in mice with Alzheimer's disease induced by amyloid β(25-35) (Aβ(25-35)) injection. The protective effect of an oligonol against Aβ(25-35)-induced memory impairment was investigated in an in vivo Alzheimer's mouse model. The aggregation of Aβ25-35 was induced by incubation at 37°C for 3 days before injection into mice brains (5 nmol/mouse), and then oligonol was orally administered at 100 and 200 mg/kg of body weight for 2 weeks. Memory and cognition were observed in T-maze, object recognition, and Morris water maze tests. The group injected with Aβ(25-35) showed impairments in both recognition and memory. However, novel object recognition and new route awareness abilities were dose dependently improved by the oral administration of oligonol. In addition, the results of the Morris water maze test indicated that oligonol exerted protective activity against cognitive impairment induced by Aβ(25-35). Furthermore, nitric oxide formation and lipid peroxidation were significantly elevated by Aβ(25-35), whereas oligonol treatment significantly decreased nitric oxide formation and lipid peroxidation in the brain, liver, and kidneys. The present results suggest that oligonol improves Aβ(25-35)-induced memory deficit and cognition impairment. Copyright © 2014 Elsevier Inc. All rights reserved.

[Isolation and purification of primary Kupffer cells from mouse liver].

PubMed

Sun, Chao; Luo, Qingbo; Lu, Xiuxian; Zheng, Daofeng; He, Diao; Wu, Zhongjun

2016-08-01

Objective To isolate and purify Kupffer cells (KCs) from BALB/c mice by an efficient method of low-speed centrifugation and rapid adherence. Methods The mouse liver tissue was perfused in situ and digested with 0.5 g/L collagenase type IV in vitro by water bath. Then, through the low-speed centrifugation, KCs were separated from the mixed hepatocytes, and purified by rapid adherent characteristics. Finally, the production and activity of KCs obtained by this modified method were compared with those isolated by Percoll density gradient centrifugation. We used F4/80 antibody immunofluorescence technique to observe morphological features of KCs, flow cytometry (FCM) to detect the expression of F4/80 antibody and the ink uptake test to observe the phagocytic activity. Moreover, using FCM, we evaluated the expressions of molecules associated with antigen presentation, including major histocompatibility complex class II (MHC II), CD40, CD86 and CD68 on the surface of KCs subjected to hypoxia/reoxygenation (H/R) modeling. And, ELISA was conducted to measure tumor necrosis factor-α (TNF-α) production of the cultured KCs following H/R. Results The yield of KCs was (5.83±0.54)×10(6) per mouse liver and the survival rate of KCs was up to 92% by low-speed centrifugation and rapid adherent method. Compared with Percoll density gradient centrifugation [the yield of KCs was (2.19±0.43)×10(6) per liver], this new method significantly improved the yield of KCs. F4/80 immunofluorescence showed typical morphologic features of KCs such as spindle or polygon shapes and FCM identified nearly 90% F4/80 positive cells. The phagocytic assay showed that lots of ink particles were phagocytosed into the isolated cells. KC H/R models expressed more MHC II, CD40 and CD86 and produced more TNF-α participating in inflammation. Conclusion The efficient method to isolate and purify KCs from BALB /c mice has been successfully established.

Diethylnitrosamine initiation does not alter clofibric acid-induced hepatocarcinogenesis in the rat.

PubMed

Michel, Cecile; Desdouets, Chantal; Slaoui, Mohamed; Isaacs, Kevin Robert; Roberts, Ruth Angela; Boitier, Eric

2007-09-01

Clofibric acid (CLO) is a nongenotoxic hepatocarcinogen in rodents that causes altered hepatocellular foci and/or neoplasms. Initiation by DNA-damaging agents such as diethylnitrosamine (DEN) accelerates focus and tumor appearance and could therefore significantly contribute to shortening of the regulatory 2-year rodent carcinogenicity bioassays. However, it is crucial to evaluate the histological and molecular impact of initiation with DEN on hepatocarcinogenesis promoted by CLO. Male F344 rats were given a single nonnecrogenic injection of DEN (0 or 30 mg/kg) followed by Control diet or CLO (5000 ppm) in diet for up to 20 months. Histopathology and gene expression profiling were performed in liver tumors and surrounding nontumoral liver tissues. The molecular signature of DEN was characterized and its histopathological and immunohistopathological effects on focus and tumor types were also determined. Although foci and tumors appeared earlier in the DEN+CLO-treated group compared to the group treated with CLO alone, DEN had little impact on gene expression in nontumoral tissues since the gene expression profiles were highly similar between Control and DEN-treated rats, and DEN+CLO- and CLO-treated rats. Finally, tumors obtained from DEN+CLO and CLO-treated groups displayed highly correlated gene expression profiles (r>0.83, independently of the time-point). The pathways involved in tumor development revealed by Gene Ontology functional analysis are similar when driven either by spontaneous initiation or by a chemically induced initiation step. Our work described here may contribute to the design optimization of shorter preclinical tests for the evaluation of the nongenotoxic hepatocarcinogenic potential of drugs under development.

Acute liver injury induced by weight-loss herbal supplements.

PubMed

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.

Acute liver injury induced by weight-loss herbal supplements

PubMed Central

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

2010-01-01

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. PMID:21173910

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

PubMed

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.

Cyanidin-3-O-β-glucoside inhibits lipopolysaccharide-induced inflammatory response in mouse mastitis model

PubMed Central

Fu, Yunhe; Wei, Zhengkai; Zhou, Ershun; Zhang, Naisheng; Yang, Zhengtao

2014-01-01

Cyanidin-3-O-β-glucoside (C3G) (CAS number 7084-24-4), a typical anthocyanin pigment that exists in the human diet, has been reported to have anti-inflammatory properties. However, the effect of C3G on lipopolysaccharide (LPS)-induced mastitis and the molecular mechanisms have not been investigated. In this study, we detected the protective effects of C3G on a LPS-induced mouse mastitis model and investigated the molecular mechanisms in LPS-stimulated mouse mammary epithelial cells (MMECs). Our results showed that C3G could attenuate mammary histopathologic changes and myeloperoxidase activity, and inhibit TNF-α, interleukin (IL)-1β, and IL-6 production caused by LPS. Meanwhile, C3G dose-dependently inhibited TNF-α and IL-6 in LPS-stimulated MMECs. C3G suppressed LPS-induced nuclear factor-κB (NF-κB) and interferon regulatory factor 3 (IRF3) activation. Furthermore, C3G disrupted the formation of lipid rafts by depleting cholesterol. Moreover, C3G activated liver X receptor (LXR)-ABCG1-dependent cholesterol efflux. Knockdown of LXRα abrogated the anti-inflammatory effects of C3G. In conclusion, C3G has a protective effect on LPS-induced mastitis. The promising anti-inflammatory mechanisms of C3G are associated with upregulation of the LXRα-ABCG1 pathway which result in disrupting lipid rafts by depleting cholesterol, thereby suppressing toll-like receptor 4-mediated NF-κB and IRF3 signaling pathways induced by LPS. PMID:24752550

Fatty acid binding protein-4 (FABP4) is a hypoxia inducible gene that sensitizes mice to liver ischemia/re-perfusion injury

PubMed Central

Hu, Bingfang; Guo, Yan; Garbacz, Wojciech G.; Jiang, Mengxi; Xu, Meishu; Huang, Hai; Tsung, Allan; Billiar, Timothy R.; Ramakrishnan, Sadeesh K.; Shah, Yatrik; Lam, Karen S. L.; Huang, Min; Xie, Wen

2016-01-01

Background & Aims Fatty acid binding protein 4 (FABP4) has been known as a mediator of inflammatory response in the macrophages and adipose tissue, but its hepatic function is poorly understood. The goal of this study is to investigate the role of FABP4 in liver ischemia/reperfusion (I/R), a clinical condition involves both hypoxia and inflammation. Methods To examine the I/R regulation of FABP4, mice were subjected to I/R surgery before being measured for FABP4 gene expression. Both loss-of-function (by using a pharmacological FABP4 inhibitor) and gain-of-function (by adenoviral overexpression of FABP4) were used to determine the functional relevance of FABP4 expression and its regulation during I/R. To determine the hypoxia responsive regulation of FABP4, primary mouse hepatocytes were exposed to hypoxia. The FABP4 gene promoter was cloned and its regulation by hypoxia inducible factor 1α (HIF-1α) was characterized by luciferase reporter gene, electrophoretic mobility shift, and chromatin immunoprecipitation assays. Results We found that the hepatic expression of FABP4 was markedly induced by I/R. At the functional level, pharmacological inhibition of FABP4 alleviated the I/R injury, whereas adenoviral overexpression of FABP4 sensitized mice to I/R injury. We also showed that exposure of primary hepatocytes to hypoxia or transgenic overexpression of HIF-1α in the mouse liver was sufficient to induce the expression of FABP4. Our promoter analysis established FABP4 as a novel transcriptional target of HIF-1α. Conclusions FABP4 is a hypoxia inducible gene that sensitizes mice to liver I/R injury. FABP4 may represent a novel therapeutic target, and FABP4 inhibitors may be used as therapeutic agents to manage hepatic I/R injury. PMID:26070408

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

PubMed

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

2018-04-28

To improve outcomes of two-staged hepatectomies for large/multiple liver tumors, portal vein ligation (PVL) has been combined with parenchymal transection (associating liver partition and portal vein ligation for staged hepatectomy [coined ALPPS]) 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. c-Jun N-terminal kinase (JNK1 [Mapk8]) activity was reduced through SP600125 to evaluate its effects on IHH signaling. Recombinant IHH was injected after JNK1 diminution to substantiate their relationship during accelerated liver regeneration. Transcriptomic analysis linked Ihh to Mapk8. JNK1 upregulation after ALPPS was validated and preceded the IHH peak. On immunofluorescence, JNK1 and IHH co-localized in alpha-smooth muscle actin-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 hepatic stellate cells 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. Associating liver partition and portal vein ligation for staged hepatectomy (so called ALPPS), is a new two-staged approach to hepatectomy, which induces an unprecedented acceleration of liver

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoshikawa, Yukitaka; Miyashita, Taishi; Higuchi, Satonori

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 hepatotoxicmore » 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 m

Folate supplementation differently affects uracil content in DNA in the mouse colon and liver

USDA-ARS?s Scientific Manuscript database

High folate intake may increase the risk of cancer, especially in the elderly. The present study examined the effects of ageing and dietary folate on uracil misincorporation into DNA, which has a mutagenic effect, in the mouse colon and liver. Old (18 months; n 42) and young (4 months; n 42) male C5...

Identification of Organ-Enriched Protein Biomarkers of Acute Liver Injury by Targeted Quantitative Proteomics of Blood in Acetaminophen- and Carbon-Tetrachloride-Treated Mouse Models and Acetaminophen Overdose Patients.

PubMed

Qin, Shizhen; Zhou, Yong; Gray, Li; Kusebauch, Ulrike; McEvoy, Laurence; Antoine, Daniel J; Hampson, Lucy; Park, Kevin B; Campbell, David; Caballero, Juan; Glusman, Gustavo; Yan, Xiaowei; Kim, Taek-Kyun; Yuan, Yue; Wang, Kai; Rowen, Lee; Moritz, Robert L; Omenn, Gilbert S; Pirmohamed, Munir; Hood, Leroy

2016-10-07

Organ-enriched blood proteins, those produced primarily in one organ and secreted or exported to the blood, potentially afford a powerful and specific approach to assessing diseases in their cognate organs. We demonstrate that quantification of organ-enriched proteins in the blood offers a new strategy to find biomarkers for diagnosis and assessment of drug-induced liver injury (and presumably the assessment of other liver diseases). We used selected reaction monitoring (SRM) mass spectrometry to quantify 81 liver-enriched proteins plus three aminotransferases (ALT1, AST1, and AST2) in plasma of C57BL/6J and NOD/ShiLtJ mice exposed to acetaminophen or carbon tetrachloride. Plasma concentrations of 49 liver-enriched proteins were perturbed significantly in response to liver injury induced by one or both toxins. We validated four of these toxin-responsive proteins (ALDOB, ASS1, BHMT, and GLUD1) by Western blotting. By both assays, these four proteins constitute liver injury markers superior to currently employed markers such as ALT and AST. A similar approach was also successful in human serum where we had analyzed 66 liver-enriched proteins in acetaminophen overdose patients. Of these, 23 proteins were elevated in patients; 15 of 23 overlapped with the concentration-increased proteins in the mouse study. A combination of 5 human proteins, AGXT, ALDOB, CRP, FBP1, and MMP9, provides the best diagnostic performance to distinguish acetaminophen overdose patients from controls (sensitivity: 0.85, specificity: 0.84, accuracy: 85%). These five blood proteins are candidates for detecting acetaminophen-induced liver injury using next-generation diagnostic devices (e.g, microfluidic ELISA assays).

An Inducible Transgenic Mouse Model for Immune Mediated Hepatitis Showing Clearance of Antigen Expressing Hepatocytes by CD8+ T Cells

PubMed Central

Cebula, Marcin; Ochel, Aaron; Hillebrand, Upneet; Pils, Marina C.; Schirmbeck, Reinhold; Hauser, Hansjörg; Wirth, Dagmar

2013-01-01

The liver has the ability to prime immune responses against neo antigens provided upon infections. However, T cell immunity in liver is uniquely modulated by the complex tolerogenic property of this organ that has to also cope with foreign agents such as endotoxins or food antigens. In this respect, the nature of intrahepatic T cell responses remains to be fully characterized. To gain deeper insight into the mechanisms that regulate the CD8+ T cell responses in the liver, we established a novel OVA_X_CreERT2 mouse model. Upon tamoxifen administration OVA antigen expression is observed in a fraction of hepatocytes, resulting in a mosaic expression pattern. To elucidate the cross-talk of CD8+ T cells with antigen-expressing hepatocytes, we adoptively transferred Kb/OVA257-264-specific OT-I T cells to OVA_X_CreERT2 mice or generated triple transgenic OVA_X CreERT2_X_OT-I mice. OT-I T cells become activated in OVA_X_CreERT2 mice and induce an acute and transient hepatitis accompanied by liver damage. In OVA_X_CreERT2_X_OT-I mice, OVA induction triggers an OT-I T cell mediated, fulminant hepatitis resulting in 50% mortality. Surviving mice manifest a long lasting hepatitis, and recover after 9 weeks. In these experimental settings, recovery from hepatitis correlates with a complete loss of OVA expression indicating efficient clearance of the antigen-expressing hepatocytes. Moreover, a relapse of hepatitis can be induced upon re-induction of cured OVA_X_CreERT2_X_OT-I mice indicating absence of tolerogenic mechanisms. This pathogen-free, conditional mouse model has the advantage of tamoxifen inducible tissue specific antigen expression that reflects the heterogeneity of viral antigen expression and enables the study of intrahepatic immune responses to both de novo and persistent antigen. It allows following the course of intrahepatic immune responses: initiation, the acute phase and antigen clearance. PMID:23869228

Toxicogenomic Dissection of the Perfluorooctanoic Acid Transcript Profile in Mouse Liver: Evidence for Involvement of the Nuclear Receptors PPARα and CAR

EPA Science Inventory

A number of perfluorinated alkyl acids including perfluorooctanoic acid (PFOA) elicit effects similar to peroxisome proliferator chemicals (PPC) in mouse and rat liver. There is strong evidence that PPC cause many of their effects related to liver carcinogenesis through the nucle...

PPARα siRNA–Treated Expression Profiles Uncover the Causal Sufficiency Network for Compound-Induced Liver Hypertrophy

PubMed Central

Dai, Xudong; Souza, Angus T. De; Dai, Hongyue; Lewis, David L; Lee, Chang-kyu; Spencer, Andy G; Herweijer, Hans; Hagstrom, Jim E; Linsley, Peter S; Bassett, Douglas E; Ulrich, Roger G; He, Yudong D

2007-01-01

Uncovering pathways underlying drug-induced toxicity is a fundamental objective in the field of toxicogenomics. Developing mechanism-based toxicity biomarkers requires the identification of such novel pathways and the order of their sufficiency in causing a phenotypic response. Genome-wide RNA interference (RNAi) phenotypic screening has emerged as an effective tool in unveiling the genes essential for specific cellular functions and biological activities. However, eliciting the relative contribution of and sufficiency relationships among the genes identified remains challenging. In the rodent, the most widely used animal model in preclinical studies, it is unrealistic to exhaustively examine all potential interactions by RNAi screening. Application of existing computational approaches to infer regulatory networks with biological outcomes in the rodent is limited by the requirements for a large number of targeted permutations. Therefore, we developed a two-step relay method that requires only one targeted perturbation for genome-wide de novo pathway discovery. Using expression profiles in response to small interfering RNAs (siRNAs) against the gene for peroxisome proliferator-activated receptor α (Ppara), our method unveiled the potential causal sufficiency order network for liver hypertrophy in the rodent. The validity of the inferred 16 causal transcripts or 15 known genes for PPARα-induced liver hypertrophy is supported by their ability to predict non-PPARα–induced liver hypertrophy with 84% sensitivity and 76% specificity. Simulation shows that the probability of achieving such predictive accuracy without the inferred causal relationship is exceedingly small (p < 0.005). Five of the most sufficient causal genes have been previously disrupted in mouse models; the resulting phenotypic changes in the liver support the inferred causal roles in liver hypertrophy. Our results demonstrate the feasibility of defining pathways mediating drug-induced toxicity from

Inflammation-induced effects on iron-related proteins in splenic macrophages and the liver in mice.

PubMed

Sukumaran, Abitha; Venkatraman, Aparna; Jacob, Molly

2012-06-15

Anemia of inflammation is characterized by disturbances in systemic iron homeostasis. In order to better understand the events involved, we carried out a time-course study on the effects of acute and chronic inflammation on iron-related proteins in mouse splenic macrophages and the liver. Mice were sacrificed at various time points ranging from 0 h up to 4 weeks after induction of inflammation with turpentine oil. Expression levels of iron-related proteins in the splenic macrophages and liver were determined. Iron levels in the serum, spleen and liver were also measured. Hepatic hepcidin was found to be induced in response to inflammation. In the macrophages, expression levels of ferroportin and TfR1 were decreased at some of the time points. The expression of hepatic TfR1 and ferritin was significantly higher at the early time points. Ferritin levels in the liver decreased progressively thereafter; this was associated with significantly higher ferroportin expression in the liver, despite high levels of hepcidin, suggesting that hepcidin may not regulate ferroportin levels in the liver, unlike in the macrophages. The effects of hepcidin, thus, appeared to be tissue-specific. Serum iron levels were decreased initially; these then rose and were associated with decreasing iron levels in the liver and spleen. Thus, inflammation affected the expression levels of many proteins involved in iron homeostasis in splenic macrophages and the liver, with differences seen in the effects at these 2 sites. These effects are likely to contribute to the development of anemia of inflammation. Copyright © 2012 Elsevier Inc. All rights reserved.

Flow-cytometric separation and enrichment of hepatic progenitor cells in the developing mouse liver.

PubMed

Suzuki, A; Zheng, Y; Kondo, R; Kusakabe, M; Takada, Y; Fukao, K; Nakauchi, H; Taniguchi, H

2000-12-01

Stem cells responsible for tissue maintenance and repair are found in a number of organs. However, hepatic stem cells assumed to play a key role in liver development and regeneration remain to be well characterized. To address this issue, we set up a culture system in which primitive hepatic progenitor cells formed colonies. By combining this culture system with fluorescence-activated cell sorting (FACS), cells forming colonies containing distinct hepatocytes and cholangiocytes were identified in the fetal mouse liver. These cells express both CD49f and CD29 (alpha6 and beta1 integrin subunits), but do not mark for hematopoietic antigens such as CD45, TER119, and c-Kit. When transplanted into the spleen, these cells migrated to the recipient liver and differentiated into liver parenchymal cells. Our data demonstrate that hepatic progenitor cells are enriched by FACS and suggest approaches to supplanting organ allografting and improving artificial-organ hepatic support.

Role of the inflammasome in acetaminophen-induced liver injury and acute liver failure.

PubMed

Woolbright, Benjamin L; Jaeschke, Hartmut

2017-04-01

Drug-induced acute liver failure carries a high morbidity and mortality rate. Acetaminophen overdose is the number one cause of acute liver failure and remains a major problem in Western medicine. Administration of N-acetyl cysteine is an effective antidote when given before the initial rise in toxicity; however, many patients present to the hospital after this stage occurs. As such, treatments which can alleviate late-stage acetaminophen-induced acute liver failure are imperative. While the initial mechanisms of toxicity are well described, a debate has recently occurred in the literature over whether there is a second phase of injury, mediated by inflammatory processes. Critical to this potential inflammatory process is the activation of caspase-1 and interleukin-1β by a molecular complex known as the inflammasome. Several different stimuli for the formation of multiple different inflammasome complexes have been identified. Formation of the NACHT, leucine-rich repeat (LRR) and pyrin (PYD) domains-containing protein 3 (Nalp3) inflammasome in particular, has directly been attributed to late-stage acetaminophen toxicity. In this review, we will discuss the mechanisms of acetaminophen-induced liver injury in mice and man with a particular focus on the role of inflammation and the inflammasome. Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Hepatoprotective effect of engineered silver nanoparticles coated bioactive compounds against diethylnitrosamine induced hepatocarcinogenesis in experimental mice.

PubMed

Prasannaraj, Govindaraj; Venkatachalam, Perumal

2017-02-01

Nanoparticle based drug delivery can rapidly improves the therapeutic potential of anti-cancer agents. The present study focused to evaluate the hepatoprotective activity of silver nanoparticles (AgNPs) synthesized using aqueous extracts of Andrographis paniculata leaves (ApAgNPs) and Semecarpus anacardium nuts (SaAgNPs) against diethylnitrosamine (DEN) induced liver cancer in mice model. The physico-chemical properties of synthesized AgNPs were characterized by Fourier transform infrared (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), X-ray Diffraction (XRD), Energy Dispersive X-ray (EDX) spectrum, Zeta potential and Dynamic Light Scattering (DLS) analysis. The surface plasmon resonance (SPR) absorption spectrum revealed a strong peak at 420nm for both SaAgNPs and ApAgNPs. FTIR results exhibited the presence of possible functional groups in the synthesized AgNPs. TEM analysis determined the hexagonal, and spherical shape of the synthesized silver nanoparticles. The XRD and SAED pattern confirmed the crystalline nature and crystalline size of the AgNPs. EDX result clearly showed strong silver signals in the range between 2 and 4keV. Zeta potential measurements indicated a sharp peak at -3.93 and -13.8mV for ApAgNPs and SaAgNPs, respectively. DLS measurement expressed the particle size distribution was 70 and 60nm for ApAgNPs and SaAgNPs, respectively. DEN (20mg/kg b.wt.) was subjected to induce liver cancer in mice for 8weeks and treated with biosynthesized silver nanoparticles. Interestingly, ApAgNPs and SaAgNPs treated DEN induced animal groups show a decreased level of aspartate amino transferase (AST), alanine amino transferase (ALT), serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) activity and elevated level of catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST) and superoxide dismutase (SOD) activity over untreated DEN control

Altered cytochrome P450 activities and expression levels in the liver and intestines of the monosodium glutamate-induced mouse model of human obesity.

PubMed

Tomankova, Veronika; Liskova, Barbora; Skalova, Lenka; Bartikova, Hana; Bousova, Iva; Jourova, Lenka; Anzenbacher, Pavel; Ulrichova, Jitka; Anzenbacherova, Eva

2015-07-15

Cytochromes P450 (CYPs) are enzymes present from bacteria to man involved in metabolism of endogenous and exogenous compounds incl. drugs. Our objective was to assess whether obesity leads to changes in activities and expression of CYPs in the mouse liver, small intestine and colon. An obese mouse model with repeated injection of monosodium glutamate (MSG) to newborns was used. Controls were treated with saline. All mice were sacrificed at 8 months. In the liver and intestines, levels of CYP mRNA and proteins were analyzed using RT-PCR and Western blotting. Activities of CYP enzymes were measured with specific substrates of human orthologous forms. At the end of the experiment, body weight, plasma insulin and leptin levels as well as the specific content of hepatic CYP enzymes were increased in obese mice. Among CYP enzymes, hepatic CYP2A5 activity, protein and mRNA expression increased most significantly in obese animals. Higher activities and protein levels of hepatic CYP2E1 and 3A in the obese mice were also found. No or a weak effect on CYPs 2C and 2D was observed. In the small intestine and colon, no changes of CYP enzymes were detected except for increased expression of CYP2E1 and decreased expression of CYP3A mRNAs in the colon of the obese mice. Results of our study suggest that the specific content and activities of some liver CYP enzymes (especially CYP2A5) can be increased in obese mice. Higher activity of CYP2A5 (CYP2A6 human ortholog) could lead to altered metabolism of drug substrates of this enzyme (valproic acid, nicotine, methoxyflurane). Copyright © 2015 Elsevier Inc. All rights reserved.

Exploring the Potential Role of Chemopreventive Agent, Hesperetin Conjugated Pegylated Gold Nanoparticles in Diethylnitrosamine-Induced Hepatocellular Carcinoma in Male Wistar Albino Rats.

PubMed

Gokuladhas, Krishnan; Jayakumar, Subramaniyan; Rajan, Balan; Elamaran, Ramasamy; Pramila, Chengalvarayan Subramani; Gopikrishnan, Mani; Tamilarasi, Sasivarman; Devaki, Thiruvengadam

2016-04-01

Liver cancer is the fifth most common cancer and is still one of the leading causes of death world wide, due to food additives, alcohol, fungal toxins, air, toxic industrial chemicals, and water pollutants. Chemopreventive drugs play a potential role in liver cancer treatment. Obviously in the production of anticancer drugs, the factors like poor solubility, bioavailability, biocompatibility, limited chemical stability, large amount of dose etc., plays a major role. Against this backdrop, the idea of designing the chemopreventive nature of bio flavanoid hesperetin (HP) drug conjugated with pegylated gold nanoparticles to increasing the solubility, improve bioavailability and enhance the targeting capabilities of the drug during diethylnitrosamine (DEN) induced liver cancer in male wistar albino rats. The dose fixation studies and the toxicity of pure HP and HP conjugated gold nanoparticles (Au-mPEG(5000)-S-HP) were analysed. After concluded the dose fixation and toxicity studies the experimental design were segregated in six groups for the anticancer analysis of DEN induced HCC for 16 weeks. After the experimental period the body weight, relative liver weight, number of nodules and size of nodules, the levels of tumor markers like CEA, AFP and the level of lipid peroxidation, lipid hydroperoxides and the activities of antioxidant enzymes were assessed. The administration of DEN to rats resulted in increased relative liver weight and serum marker enzymes aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase, and gamma glutamyl transpeptidase. The levels of lipid peroxides elevated (in both serum and tissue) with subsequent decrease in the final body weight and tissue antioxidants like superoxide dismutase, catalase, reduced glutathione, glutathione peroxidise, and glutathione reductase. HP supplementation (20 mg/kg b.wt) significantly attenuated these alterations, thereby showing potent anticancer effect in liver cancer and the

Toxicogenomic Dissection of the Perfluorooctanoic Acid Transcript Profile in Mouse Liver: Evidence for the Involvement of Nuclear Receptors PPARα and CAR

EPA Science Inventory

A number of perfluorinated alkyl acids including perfluorooctanoic acid (PFOA) elicit effects similar to peroxisome proliferator chemicals (PPC) in mouse and rat liver. There is strong evidence that PPC cause many of their effects linked to liver cancer through the nuclear recep...

Imaging of pharmacokinetic rates of indocyanine green in mouse liver with a hybrid fluorescence molecular tomography/x-ray computed tomography system.

PubMed

Zhang, Guanglei; Liu, Fei; Zhang, Bin; He, Yun; Luo, Jianwen; Bai, Jing

2013-04-01

Pharmacokinetic rates have the potential to provide quantitative physiological and pathological information for biological studies and drug development. Fluorescence molecular tomography (FMT) is an attractive imaging tool for three-dimensionally resolving fluorophore distribution in small animals. In this letter, pharmacokinetic rates of indocyanine green (ICG) in mouse liver are imaged with a hybrid FMT and x-ray computed tomography (XCT) system. A recently developed FMT method using structural priors from an XCT system is adopted to improve the quality of FMT reconstruction. In the in vivo experiments, images of uptake and excretion rates of ICG in mouse liver are obtained, which can be used to quantitatively evaluate liver function. The accuracy of the results is validated by a fiber-based fluorescence measurement system.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Mahendra Pratap; School of Bioengineering and Biosciences, Department of Zoology, Lovely Professional University, Phagwara, 144411, Punjab; Kim, Ki Young

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{sup −/−}). We found that MsrA{sup −/−} mice were more susceptible to APAP-induced acute liver injury than wild-type mice (MsrA{sup +/+}). The central lobule area of the MsrA{sup −/−} liver was more impaired with necrotic lesions. Serum alanine transaminase, aspartate transaminase, and lactate dehydrogenase levels were significantly higher in MsrA{supmore » −/−} than in MsrA{sup +/+} 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{sup −/−} than in MsrA{sup +/+} livers. Expression and nuclear accumulation of Nrf2 and its target gene expression were significantly elevated in MsrA{sup −/−} than in MsrA{sup +/+} 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.« less

ASSESSING MOLECULAR MECHANISMS OF THREE TOXICOLOGICALLY DIFFERENT CONAZOLES BASED ON PATHWAY ANALYSIS OF MOUSE LIVER TRANSCRIPTOMES

EPA Science Inventory

The present study was designed to identify the underlying molecular mechanism for the induction of mouse liver tumors by structurally-related conazoles. CD-1 mice were treated with the tumor producing conazoles, triadimefon (1800, 500, or 100 ppm), or propiconazole (2500, 500, or...

Liver X receptor agonist prevents LPS-induced mastitis in mice.

PubMed

Fu, Yunhe; Tian, Yuan; Wei, Zhengkai; Liu, Hui; Song, Xiaojing; Liu, Wenbo; Zhang, Wenlong; Wang, Wei; Cao, Yongguo; Zhang, Naisheng

2014-10-01

Liver X receptor-α (LXR-α) which belongs to the nuclear receptor superfamily, is a ligand-activated transcription factor. Best known for its ability to regulate lipid metabolism and transport, LXRs have recently also been implicated in regulation of inflammatory response. The aim of this study was to investigate the preventive effects of synthetic LXR-α agonist T0901317 on LPS-induced mastitis in mice. The mouse model of mastitis was induced by injection of LPS through the duct of mammary gland. T0901317 was injected 1h before and 12h after induction of LPS intraperitoneally. The results showed that T0901317 significantly attenuated the infiltration of neutrophilic granulocytes, and the activation of myeloperoxidase (MPO); down-regulated the level of pro-inflammatory mediators including TNF-α, IL-1β, IL-6, COX-2 and PEG2; inhibited the phosphorylation of IκB-α and NF-κB p65, caused by LPS. Moreover, we report for the first time that LXR-α activation impaired LPS-induced mastitis. Taken together, these data indicated that T0901317 had protective effect on mastitis and the anti-inflammatory mechanism of T0901317 on LPS induced mastitis in mice may be due to its ability to inhibit NF-κB signaling pathway. LXR-α activation can be used as a therapeutic approach to treat mastitis. Copyright © 2014 Elsevier B.V. All rights reserved.

Fish Oil Accelerates Diet-Induced Entrainment of the Mouse Peripheral Clock via GPR120

PubMed Central

Itokawa, Misa; Nagahama, Hiroki; Ohtsu, Teiji; Furutani, Naoki; Kamagata, Mayo; Yang, Zhi-Hong; Hirasawa, Akira; Tahara, Yu; Shibata, Shigenobu

2015-01-01

The circadian peripheral clock is entrained by restricted feeding (RF) at a fixed time of day, and　insulin secretion regulates RF-induced entrainment of the peripheral clock in mice. Thus, carbohydrate-rich food may be ideal for facilitating RF-induced entrainment, although the role of dietary oils in insulin secretion and RF-induced entrainment has not been described. The soybean oil component of standard mouse chow was substituted with fish or soybean oil containing docosahexaenoic acid (DHA) and/or eicosapentaenoic acid (EPA). Tuna oil (high DHA/EPA), menhaden oil (standard), and DHA/EPA dissolved in soybean oil increased insulin secretion and facilitated RF-induced phase shifts of the liver clock as represented by the bioluminescence rhythms of PER2::LUCIFERASE knock-in mice. In this model, insulin depletion blocked the effect of tuna oil and fish oil had no effect on mice deficient for GPR120, a polyunsaturated fatty acid receptor. These results suggest food containing fish oil or DHA/EPA is ideal for adjusting the peripheral clock. PMID:26161796

N-Hydroxylation of 4-Aminobiphenyl by CYP2E1 Produces Oxidative Stress in a Mouse Model of Chemically Induced Liver Cancer

PubMed Central

Wang, Shuang; Sugamori, Kim S.; Tung, Aveline; McPherson, J. Peter; Grant, Denis M.

2015-01-01

4-Aminobiphenyl (ABP) is a trace component of cigarette smoke and hair dyes, a suspected human carcinogen and a potent rodent liver carcinogen. Postnatal exposure of mice to ABP results in a higher incidence of liver tumors in males than in females, paralleling the sex difference in human liver cancer incidence. A traditional model of ABP tumorigenesis involves initial CYP1A2-mediated N-hydroxylation, which eventually leads to production of mutagenic ABP-DNA adducts that initiate tumor growth. However, several studies have found no correlation between sex or CYP1A2 function and the DNA-damaging, mutagenic, or tumorigenic effects of ABP. Oxidative stress may be an important etiological factor for liver cancer, and it has also been linked to ABP exposure. The goals of this study were to identify novel enzyme(s) that contribute to ABP N-oxidation, and to investigate a potential role for oxidative stress in ABP liver tumorigenicity. Isozyme-selective inhibition experiments using liver microsomes from wild-type and genetically modified mice identified CYP2E1 as a major ABP N-hydroxylating enzyme. The N-hydroxylation of ABP by transiently expressed CYP2E1 produced oxidative stress in cultured mouse hepatoma cells. In vivo postnatal exposure of mice to a tumorigenic dose of ABP also produced oxidative stress in male wild-type mice, but not in male Cyp2e1(−/−) mice or in female mice. However, a stronger NRF2-associated antioxidant response was observed in females. Our results identify CYP2E1 as a novel ABP-N-oxidizing enzyme, and suggest that sex differences in CYP2E1-dependent oxidative stress and antioxidant responses to ABP may contribute to the observed sex difference in tumor incidence. PMID:25601990

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

PubMed

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 < 0.001). The optimal cutoff values by ElastPQ were 11.27, 14.89, and 18.21 kPa for predicting minimal 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.

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

PubMed

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.

Nicotinamide N‐methyltransferase expression decreases in iron overload, exacerbating toxicity in mouse hepatocytes

PubMed Central

Koppe, Tiago; Patchen, Bonnie; Cheng, Aaron; Bhasin, Manoj; Vulpe, Chris; Schwartz, Robert E.; Moreno‐Navarrete, Jose Maria; Fernandez‐Real, Jose Manuel

2017-01-01

Iron overload causes the generation of reactive oxygen species that can lead to lasting damage to the liver and other organs. The goal of this study was to identify genes that modify the toxicity of iron overload. We studied the effect of iron overload on the hepatic transcriptional and metabolomic profile in mouse models using a dietary model of iron overload and a genetic model, the hemojuvelin knockout mouse. We then evaluated the correlation of nicotinamide N‐methyltransferase (NNMT) expression with body iron stores in human patients and the effect of NNMT knockdown on gene expression and viability in primary mouse hepatocytes. We found that iron overload induced significant changes in the expression of genes and metabolites involved in glucose and nicotinamide metabolism and that NNMT, an enzyme that methylates nicotinamide and regulates hepatic glucose and cholesterol metabolism, is one of the most strongly down‐regulated genes in the liver in both genetic and dietary iron overload. We found that hepatic NNMT expression is inversely correlated with serum ferritin levels and serum transferrin saturation in patients who are obese, suggesting that body iron stores regulate human liver NNMT expression. Furthermore, we demonstrated that adenoviral knockdown of NNMT in primary mouse hepatocytes exacerbates iron‐induced hepatocyte toxicity and increases expression of transcriptional markers of oxidative and endoplasmic reticulum stress, while overexpression of NNMT partially reversed these effects. Conclusion: Iron overload alters glucose and nicotinamide transcriptional and metabolic pathways in mouse hepatocytes and decreases NNMT expression, while NNMT deficiency worsens the toxic effect of iron overload. For these reasons, NNMT may be a drug target for the prevention of iron‐induced hepatotoxicity. (Hepatology Communications 2017;1:803–815) PMID:29404495

Activation of K-ras by codon 13 mutations in C57BL/6 X C3H F1 mouse tumors induced by exposure to 1,3-butadiene.

PubMed

Goodrow, T; Reynolds, S; Maronpot, R; Anderson, M

1990-08-01

1,3-Butadiene has been detected in urban air, gasoline vapors, and cigarette smoke. It has been estimated that 65,000 workers are exposed to this chemical in occupational settings in the United States. Lymphomas, lung, and liver tumors were induced in female and male C57BL/6 X C3H F1 (hereafter called B6C3F1) mice by inhalation of 6.25 to 625 ppm 1,3-butadiene for 1 to 2 years. The objective of this study was to examine these tumors for the presence of activated protooncogenes by the NIH 3T3 transfection and nude mouse tumorigenicity assays. Transfection of DNA isolated from 7 of 9 lung tumors and 7 of 12 liver tumors induced morphological transformation of NIH 3T3 cells. Southern blot analysis indicated that the transformation induced by 6 lung and 3 liver tumor DNA samples was due to transfer of a K-ras oncogene. Four of the 7 liver tumors that were positive upon transfection contained an activated H-ras gene. The identity of the transforming gene in one of the lung tumors has not been determined but was not a member of the ras family or a met or raf gene. Eleven 1,3-butadiene-induced lymphomas were examined for transforming genes using the nude mouse tumorigenicity assay. Activated K-ras genes were detected in 2 of the 11 lymphomas assayed. DNA sequencing of polymerase chain reaction-amplified ras gene exons revealed that 9 of 11 of the activating K-ras mutations were G to C transversions in codon 13. One liver tumor contained an activated K-ras gene with mutations in both codons 60 and 61. The activating mutation in one of the K-ras genes from a lymphoma was not identified but DNA sequence analysis of amplified regions in proximity to codons 12, 13, and 61 demonstrated that the mutation was not located in or near these codons. Activation of K-ras genes by codon 13 mutations has not been found in any lung or liver tumors or lymphomas from untreated B6C3F1 mice. Thus, the K-ras activation found in 1,3-butadiene-induced B6C3F1 mouse tumors probably occurred as a

TRPM2 channels mediate acetaminophen-induced liver damage

PubMed Central

Kheradpezhouh, Ehsan; Ma, Linlin; Morphett, Arthur; Barritt, Greg J.; Rychkov, Grigori Y.

2014-01-01

Acetaminophen (paracetamol) is the most frequently used analgesic and antipyretic drug available over the counter. At the same time, acetaminophen overdose is the most common cause of acute liver failure and the leading cause of chronic liver damage requiring liver transplantation in developed countries. Acetaminophen overdose causes a multitude of interrelated biochemical reactions in hepatocytes including the formation of reactive oxygen species, deregulation of Ca2+ homeostasis, covalent modification and oxidation of proteins, lipid peroxidation, and DNA fragmentation. Although an increase in intracellular Ca2+ concentration in hepatocytes is a known consequence of acetaminophen overdose, its importance in acetaminophen-induced liver toxicity is not well understood, primarily due to lack of knowledge about the source of the Ca2+ rise. Here we report that the channel responsible for Ca2+ entry in hepatocytes in acetaminophen overdose is the Transient Receptor Potential Melanostatine 2 (TRPM2) cation channel. We show by whole-cell patch clamping that treatment of hepatocytes with acetaminophen results in activation of a cation current similar to that activated by H2O2 or the intracellular application of ADP ribose. siRNA-mediated knockdown of TRPM2 in hepatocytes inhibits activation of the current by either acetaminophen or H2O2. In TRPM2 knockout mice, acetaminophen-induced liver damage, assessed by the blood concentration of liver enzymes and liver histology, is significantly diminished compared with wild-type mice. The presented data strongly suggest that TRPM2 channels are essential in the mechanism of acetaminophen-induced hepatocellular death. PMID:24569808

Cordyceps sinensis prevents apoptosis in mouse liver with D-galactosamine/lipopolysaccharide-induced fulminant hepatic failure.

PubMed

Cheng, Yu-Jung; Cheng, Shiu-Min; Teng, Yi-Hsien; Shyu, Woei-Cherng; Chen, Hsiu-Ling; Lee, Shin-Da

2014-01-01

Cordyceps sinensis (C. sinensis) has long been considered to be an herbal medicine and has been used in the treatment of various inflammatory diseases. The present study examined the cytoprotective properties of C. sinensis on D(+)-galactosamine (GalN)/lipopolysaccharide (LPS)-induced fulminant hepatic failure. Mice were randomly assigned into control, GalN/LPS, CS 20 mg and CS 40 mg groups (C. sinensis, oral gavage, five days/week, four weeks). After receiving saline or C. sinensis, mice were intraperitoneally given GalN (800 mg/kg)/LPS (10 μg/kg). The effects of C. sinensis on TNF-α, IL-10, AST, NO, SOD, and apoptoticrelated proteins after the onset of endotoxin intoxication were determined. Data demonstrated that GalN/LPS increased hepatocyte degeneration, circulating AST, TNF-α, IL-10, and hepatic apoptosis and caspase activity. C. sinensis pre-treatment reduced AST, TNF-α, and NO and increased IL-10 and SOD in GalN/LPS induced fulminant hepatic failure. C. sinensis attenuated the apoptosis of hepatocytes, as evidenced by the TUNEL and capase-3, 6 activity analyses. In summary, C. sinensis alleviates GalN/LPS-induced liver injury by modulating the cytokine response and inhibiting apoptosis.

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

PubMed

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.

Soluble FGFR4 extracellular domain inhibits FGF19-induced activation of FGFR4 signaling and prevents nonalcoholic fatty liver disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Qiang; The First Affiliated Hospital of Xiamen University, Xiamen; Jiang, Yuan

2011-06-17

Highlights: {yields} Soluble FGFR4 extracellular domain (FGFR4-ECD) was effectively expressed. {yields} FGFR4-ECD inhibited FGF19-induced activation of FGFR4 signaling. {yields} FGFR4-ECD reduced palmitic acid-induced steatosis of HepG2 cells. {yields} FGFR4-ECD reduced tetracycline-induced fatty liver in mice. {yields} FGFR4-ECD partially restored tetracycline-repressed PPAR{alpha} expression. -- Abstract: Fibroblast growth factor receptor 4 (FGFR4) is a transmembrane tyrosine kinase receptor that plays a crucial role in the regulation of hepatic bile acid and lipid metabolism. FGFR4 underlies high-fat diet-induced hepatic steatosis, suggesting that inhibition of FGFR4 activation may be an effective way to prevent or treat nonalcoholic fatty liver disease (NAFLD). To determine whethermore » neutralization of FGFR4 ligands by soluble FGFR4 extracellular domain (FGFR4-ECD) can inhibit the activation of FGFR4, we constructed FGFR4-ECD expression vector and showed that FGFR4-ECD was effectively expressed in cells and secreted into culture medium. FGFR4-ECD inhibited FGF19-induced activation of FGFR4 signaling and reduced steatosis of HepG2 induced by palmitic acid in vitro. Furthermore, in a tetracycline-induced fatty liver model, expression of FGFR4-ECD in mouse liver reduced the accumulation of hepatic lipids and partially restored the expression of peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}), which promotes the mitochondrial fatty acid beta-oxidation but is repressed by tetracycline. Taken together, these results demonstrate that FGFR4-ECD can block FGFR4 signaling and prevent hepatic steatosis, highlighting the potential value of inhibition of FGFR4 signaling as a method for therapeutic intervention against NAFLD.« less

Phosphatase and tensin homolog-β-catenin signaling modulates regulatory T cells and inflammatory responses in mouse liver ischemia/reperfusion injury.

PubMed

Zhu, Qiang; Li, Changyong; Wang, Kunpeng; Yue, Shi; Jiang, Longfeng; Ke, Michael; Busuttil, Ronald W; Kupiec-Weglinski, Jerzy W; Zhang, Feng; Lu, Ling; Ke, Bibo

2017-06-01

The phosphatase and tensin homolog (PTEN) deleted on chromosome 10 plays an important role in regulating T cell activation during inflammatory response. Activation of β-catenin is crucial for maintaining immune homeostasis. This study investigates the functional roles and molecular mechanisms by which PTEN-β-catenin signaling promotes regulatory T cell (Treg) induction in a mouse model of liver ischemia/reperfusion injury (IRI). We found that mice with myeloid-specific phosphatase and tensin homolog knockout (PTEN M-KO ) exhibited reduced liver damage as evidenced by decreased levels of serum alanine aminotransferase, intrahepatic macrophage trafficking, and proinflammatory mediators compared with the PTEN-proficient (floxed phosphatase and tensin homolog [PTEN FL/FL ]) controls. Disruption of myeloid PTEN-activated b-catenin promoted peroxisome proliferator-activated receptor gamma (PPARγ)-mediated Jagged-1/Notch signaling and induced forkhead box P3 (FOXP3)1 Tregs while inhibiting T helper 17 cells. However, blocking of Notch signaling by inhibiting γ-secretase reversed myeloid PTEN deficiency-mediated protection in ischemia/reperfusion-triggered liver inflammation with reduced FOXP3 + and increased retinoid A receptor-related orphan receptor gamma t-mediated interleukin 17A expression in ischemic livers. Moreover, knockdown of β-catenin or PPARγ in PTEN-deficient macrophages inhibited Jagged-1/Notch activation and reduced FOXP3 + Treg induction, leading to increased proinflammatory mediators in macrophage/T cell cocultures. In conclusion, our findings demonstrate that PTEN-β-catenin signaling is a novel regulator involved in modulating Treg development and provides a potential therapeutic target in liver IRI. Liver Transplantation 23 813-825 2017 AASLD. © 2017 by the American Association for the Study of Liver Diseases.

Renal Impairment with Sublethal Tubular Cell Injury in a Chronic Liver Disease Mouse Model

PubMed Central

Ishida, Tokiko; Kotani, Hirokazu; Miyao, Masashi; Kawai, Chihiro; Jemail, Leila; Abiru, Hitoshi; Tamaki, Keiji

2016-01-01

The pathogenesis of renal impairment in chronic liver diseases (CLDs) has been primarily studied in the advanced stages of hepatic injury. Meanwhile, the pathology of renal impairment in the early phase of CLDs is poorly understood, and animal models to elucidate its mechanisms are needed. Thus, we investigated whether an existing mouse model of CLD induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) shows renal impairment in the early phase. Renal injury markers, renal histology (including immunohistochemistry for tubular injury markers and transmission electron microscopy), autophagy, and oxidative stress were studied longitudinally in DDC- and standard diet–fed BALB/c mice. Slight but significant renal dysfunction was evident in DDC-fed mice from the early phase. Meanwhile, histological examinations of the kidneys with routine light microscopy did not show definitive morphological findings, and electron microscopic analyses were required to detect limited injuries such as loss of brush border microvilli and mitochondrial deformities. Limited injuries have been recently designated as sublethal tubular cell injury. As humans with renal impairment, either with or without CLD, often show almost normal tubules, sublethal injury has been of particular interest. In this study, the injuries were associated with mitochondrial aberrations and oxidative stress, a possible mechanism for sublethal injury. Intriguingly, two defense mechanisms were associated with this injury that prevent it from progressing to apparent cell death: autophagy and single-cell extrusion with regeneration. Furthermore, the renal impairment of this model progressed to chronic kidney disease with interstitial fibrosis after long-term DDC feeding. These findings indicated that DDC induces renal impairment with sublethal tubular cell injury from the early phase, leading to chronic kidney disease. Importantly, this CLD mouse model could be useful for studying the pathophysiological mechanisms

Carbamoyl phosphate synthetase-1 is a rapid turnover biomarker in mouse and human acute liver injury.

PubMed

Weerasinghe, Sujith V W; Jang, You-Jin; Fontana, Robert J; Omary, M Bishr

2014-08-01

Several serum markers are used to assess hepatocyte damage, but they have limitations related to etiology specificity and prognostication. Identification of novel hepatocyte-specific biomarkers could provide important prognostic information and better pathogenesis classification. We tested the hypothesis that hepatocyte-selective biomarkers are released after subjecting isolated mouse hepatocytes to Fas-ligand-mediated apoptosis. Proteomic analysis of hepatocyte culture medium identified the mitochondrial matrix protein carbamoyl phosphate synthetase-1 (CPS1) among the most readily detected proteins that are released by apoptotic hepatocytes. CPS1 was also detected in mouse serum upon acute challenge with Fas-ligand or acetaminophen and in hepatocytes upon hypoosmotic stress, independent of hepatocyte caspase activation. Furthermore, CPS1 was observed in sera of mice chronically fed the hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Mouse CPS1 detectability was similar in serum and plasma, and its half-life was 126 ± 9 min. Immune staining showed that CPS1 localized to mouse hepatocytes but not ductal cells. Analysis of a few serum samples from patients with acute liver failure (ALF) due to acetaminophen, Wilson disease, or ischemia showed readily detectable CPS1 that was not observed in several patients with chronic viral hepatitis or in control donors. Notably, CPS1 rapidly decreased to undetectable levels in sera of patients with acetaminophen-related ALF who ultimately recovered, while alanine aminotransferase levels remained elevated. Therefore, CPS1 becomes readily detectable upon hepatocyte apoptotic and necrotic death in culture or in vivo. Its abundance and short serum half-life, compared with alanine aminotransferase, suggest that it may be a useful prognostic biomarker in human and mouse liver injury. Copyright © 2014 the American Physiological Society.

Apigenin inhibits d-galactosamine/LPS-induced liver injury through upregulation of hepatic Nrf-2 and PPARγ expressions in mice.

PubMed

Zhou, Rui-Jun; Ye, Hua; Wang, Feng; Wang, Jun-Long; Xie, Mei-Lin

2017-11-04

Apigenin is a natural flavonoid compound widely distributed in a variety of vegetables, medicinal plants and health foods. This study aimed to examine the protective effect of apigenin against d-galactosamine (D-GalN)/lipopolysaccharide (LPS)-induced mouse liver injury and to investigate the potential biochemical mechanisms. The results showed that after oral administration of apigenin 100-200 mg/kg for 7 days, the levels of serum alanine aminotransferase and aspartate aminotransferase were decreased, and the severity of liver injury was alleviated. Importantly, apigenin pretreatment increased the levels of hepatic nuclear factor erythroid 2-related factor 2 (Nrf-2) and peroxisome proliferator-activated receptor γ (PPARγ) protein expressions as well as superoxide dismutase, catalase, glutathione S-transferase and glutathione reductase activities, decreased the levels of hepatic nuclear factor-κB (NF-κB) protein expression and tumor necrosis factor-α. These findings demonstrated that apigenin could prevent the D-GalN/LPS-induced liver injury in mice, and its mechanisms might be associated with the increments of Nrf-2-mediated antioxidative enzymes and modulation of PPARγ/NF-κB-mediated inflammation. Copyright © 2017 Elsevier Inc. All rights reserved.

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

PubMed Central

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

2016-01-01

AIM 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. METHODS Liver stiffness was measured in sixty-eight rabbits with CCl4-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. RESULTS LSM by ElastPQ was significantly correlated with histologic fibrosis stage (r = 0.85, P < 0.001). The optimal cutoff values by ElastPQ were 11.27, 14.89, and 18.21 kPa for predicting minimal 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. CONCLUSION ElastPQ is an available, convenient, objective and non-invasive technique for assessing liver stiffness in rabbits with CCl4-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. PMID:28028365

Proto-oncogene activation in liver tumors of hepatocarcinogenesis-resistant strains of mice.

PubMed

Stanley, L A; Devereux, T R; Foley, J; Lord, P G; Maronpot, R R; Orton, T C; Anderson, M W

1992-12-01

Activation of the ras family of oncogenes occurs frequently in liver tumors of the B6C3F1 mouse, a strain which is highly sensitive to hepatocarcinogenesis. Many other mouse strains are much more resistant to hepatocarcinogenesis; the aim of this study was to determine the frequency and pattern of oncogene activation in spontaneous and chemically induced liver tumors of three such strains, the C57BL/6J, the C57BL/6 x DBA/2 F1 hybrid (B6D2F1) and the C57BL/6 x Balb/c F1 hybrid (B6BCF1). The C57BL/6, DBA/2 and Balb/c strains are all relatively resistant to spontaneous hepatocarcinogenesis (1.5-3.6% of animals develop liver tumors in 2 years); with regard to chemically induced hepatocarcinogenesis the Balb/c is highly resistant, the C57BL/6 has low susceptibility and the DBA/2 has low to moderate susceptibility. The nude mouse tumorigenicity assay was used to search for activated oncogenes in 15 C57BL/6J liver tumors induced by a single neonatal dose of vinyl carbamate (VC, 0.15 mumol/g body weight). Three tumors contained H-ras genes activated by point mutations at codon 61 and one contained a non-ras oncogene. The polymerase chain reaction and allele-specific oligonucleotide hybridization were used to study H-ras mutations in spontaneous and VC-induced tumors from all three strains of mice. The frequency of H-ras codon 61 mutations in tumors induced by 0.15 mumol/g body weight VC in the C57BL/6J mouse (5/37) was similar to that in spontaneous tumors (2/9); surprisingly, tumors induced by a lower dose of VC (0.03 mumol/g body weight) had a higher frequency of H-ras mutations (12/28). The frequencies of H-ras activation detected in VC (0.03 mumol/g body weight)-induced tumors from the two F1 hybrids studied differed markedly. Only one VC-induced B6BCF1 tumor contained a mutated H-ras gene (1/10), whereas the majority of B6D2F1 tumors contained such mutations (23/33). Several spontaneous B6D2F1 liver tumors contained H-ras codon 61 mutations (6/15). Thus, H

Carvedilol induces endogenous hydrogen sulfide tissue concentration changes in various mouse organs.

PubMed

Wiliński, Bogdan; Wiliński, Jerzy; Somogyi, Eugeniusz; Piotrowska, Joanna; Góralska, Marta; Macura, Barbara

2011-01-01

Carvedilol, a third generation non-selective adrenoreceptor blocker, is widely used in cardiology. Its action has been proven to reach beyond adrenergic antagonism and involves multiple biological mechanisms. The interaction between carvedilol and endogenous 'gasotransmitter' hydrogen sulfide (H2S) is unknown. The aim of the study is to assess the influence of carvedilol on the H2S tissue level in mouse brain, liver, heart and kidney. Twenty eight SJL strain female mice were administered intraperitoneal injections of 2.5 mg/kg b.w./d (group D1, n=7), 5 mg/kg b.w./d (group D2, n=7) or 10 mg/kg b.w./d of carvedilol (group D3, n=7). The control group (n=7) received physiological saline in portions of the same volume (0.2 ml). Measurements of the free tissue H2S concentrations were performed according to the modified method of Siegel. A progressive decline in H2S tissue concentration along with an increase in carvedilol dose was observed in the brain (12.5%, 13.7% and 19.6%, respectively). Only the highest carvedilol dose induced a change in H2S tissue level in the heart - an increase by 75.5%. In the liver medium and high doses of carvedilol increased the H2S level by 48.1% and 11.8%, respectively. In the kidney, group D2 showed a significant decrease of H2S tissue level (22.5%), while in the D3 group the H2S concentration increased by 12.9%. Our study has proven that carvedilol affects H2S tissue concentration in different mouse organs.

Assessment of hemodynamics in a rat model of liver cirrhosis with precancerous lesions using multislice spiral CT perfusion imaging.

PubMed

Ma, Guolin; Bai, Rongjie; Jiang, Huijie; Hao, Xuejia; Ling, Zaisheng; Li, Kefeng

2013-01-01

To develop an optimal scanning protocol for multislice spiral CT perfusion (CTP) imaging to evaluate hemodynamic changes in liver cirrhosis with diethylnitrosamine- (DEN-) induced precancerous lesions. Male Wistar rats were randomly divided into the control group (n = 80) and the precancerous liver cirrhosis group (n = 40). The control group received saline injection and the liver cirrhosis group received 50 mg/kg DEN i.p. twice a week for 12 weeks. All animals underwent plain CT scanning, CTP, and contrast-enhanced CT scanning. Scanning parameters were optimized by adjusting the diatrizoate concentration, the flow rate, and the delivery time. The hemodynamics of both groups was further compared using optimized multislice spiral CTP imaging. High-quality CTP images were obtained with following parameters: 150 kV; 150 mAs; 5 mm thickness, 5 mm interval; pitch, 1; matrix, 512 × 512; and FOV, 9.6 cm. Compared to the control group, the liver cirrhosis group had a significantly increased value of the hepatic arterial fraction and the hepatic artery perfusion (P < 0.05) but significantly decreased hepatic portal perfusion and mean transit time (P < 0.05). Multislice spiral CTP imaging can be used to evaluate the hemodynamic changes in the rat model of liver cirrhosis with precancerous lesions.

Dysregulation of protein degradation pathways may mediate the liver injury and phospholipidosis associated with a cationic amphiphilic antibiotic drug

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mosedale, Merrie; Wu, Hong; Kurtz, C. Lisa

A large number of antibiotics are known to cause drug-induced liver injury in the clinic; however, interpreting clinical risk is not straightforward owing to a lack of predictivity of the toxicity by standard preclinical species and a poor understanding of the mechanisms of toxicity. An example is PF-04287881, a novel ketolide antibiotic that caused elevations in liver function tests in Phase I clinical studies. In this study, a mouse diversity panel (MDP), comprised of 34 genetically diverse, inbred mouse strains, was utilized to model the toxicity observed with PF-04287881 treatment and investigate potential mechanisms that may mediate the liver response.more » Significant elevations in serum alanine aminotransferase (ALT) levels in PF-04287881-treated animals relative to vehicle-treated controls were observed in the majority (88%) of strains tested following a seven day exposure. The average fold elevation in ALT varied by genetic background and correlated with microscopic findings of hepatocellular hypertrophy, hepatocellular single cell necrosis, and Kupffer cell vacuolation (confirmed as phospholipidosis) in the liver. Global liver mRNA expression was evaluated in a subset of four strains to identify transcript and pathway differences that distinguish susceptible mice from resistant mice in the context of PF-04287881 treatment. The protein ubiquitination pathway was highly enriched among genes associated with PF-04287881-induced hepatocellular necrosis. Expression changes associated with PF-04287881-induced phospholipidosis included genes involved in drug transport, phospholipid metabolism, and lysosomal function. The findings suggest that perturbations in genes involved in protein degradation leading to accumulation of oxidized proteins may mediate the liver injury induced by this drug. - Highlights: • Identified susceptible and resistant mouse strains to liver injury induced by a CAD • Liver injury characterized by single cell necrosis, and

N-Acetylcysteine Use in Non-Acetaminophen-Induced Acute Liver Failure.

PubMed

McPheeters, Chelsey M; VanArsdale, Vanessa M; Weant, Kyle A

2016-01-01

This article will review the available evidence related to the management of non-acetaminophen induced acute liver failure with N-acetylcysteine. Randomized controlled trials and a meta-analysis were included in this review. The efficacy of N-acetylcysteine in the treatment of acute liver failure from causes other than acetaminophen toxicity was evaluated. The efficacy of N-acetylcysteine in non-acetaminophen-induced acute liver failure is limited to specific patient populations. Patients classified as Coma Grade I or II are more likely to benefit from the use of this agent. The use of N-acetylcysteine is associated with improved transplant-free survival, not overall survival, in adults. N-Acetylcysteine does not improve the overall survival of patients with non-acetaminophen-induced acute liver failure but may be beneficial in those patients with Coma Grades I-II. Liver transplantation remains the only definitive therapy in advanced disease.

Lack of contribution of covalent benzo[a]pyrene-7,8-quinone-DNA adducts in benzo[a]pyrene-induced mouse lung tumorigenesis.

PubMed

Nesnow, Stephen; Nelson, Garret; Padgett, William T; George, Michael H; Moore, Tanya; King, Leon C; Adams, Linda D; Ross, Jeffrey A

2010-07-30

Benzo[a]pyrene (B[a]P) is a potent human and rodent lung carcinogen. This activity has been ascribed in part to the formation of anti-trans-7,8-dihydroxy-7,8-dihydroB[a]P-9,10-epoxide (BPDE)-DNA adducts. Other carcinogenic mechanisms have been proposed: (1) the induction of apurinic sites from radical cation processes, and (2) the metabolic formation of B[a]P-7,8-quinone (BPQ) that can form covalent DNA adducts or reactive oxygen species which can damage DNA. The studies presented here sought to examine the role of stable BPQ-DNA adducts in B[a]P-induced mouse lung tumorigenesis. Male strain A/J mice were injected intraperitoneally once with BPQ or trans-7,8-dihydroxy-7,8-dihydroB[a]P (BP-7,8-diol) at 30, 10, 3, or 0mg/kg. Lungs and livers were harvested after 24h, the DNA extracted and subjected to (32)P-postlabeling analysis. Additional groups of mice were dosed once with BPQ or BP-7,8-diol each at 30 mg/kg and tissues harvested 48 and 72 h later, or with B[a]P (50mg/kg, a tumorigenic dose) and tissues harvested 72 h later. No BPQ or any other DNA adducts were observed in lung or liver tissues 24, 48, or 72 h after the treatment with 30 mg/kg BPQ. BP-7,8-diol gave BPDE-DNA adducts at all time points in both tissues and B[a]P treatment gave BPDE-DNA adducts in the lung. In each case, no BPQ-DNA adducts were detected. Mouse body weights significantly decreased over time after BPQ or BP-7,8-diol treatments suggesting that systemic toxicity was induced by both agents. Model studies with BPQ and N-acetylcysteine suggested that BPQ is rapidly inactivated by sulfhydryl-containing compounds and not available for DNA adduction. We conclude that under these treatment conditions BPQ does not form stable covalent DNA adducts in the lungs or livers of strain A/J mice, suggesting that stable BPQ-covalent adducts are not a part of the complex of mechanisms involved in B[a]P-induced mouse lung tumorigenesis. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Liver-Directed Human Amniotic Epithelial Cell Transplantation Improves Systemic Disease Phenotype in Hurler Syndrome Mouse Model.

PubMed

Rodriguez, Natalie S; Yanuaria, Lisa; Parducho, Kevin Murphy R; Garcia, Irving M; Varghese, Bino A; Grubbs, Brendan H; Miki, Toshio

2017-07-01

Mucopolysaccharidosis type 1 (MPS1) is an inherited lysosomal storage disorder caused by a deficiency in the glycosaminoglycan (GAG)-degrading enzyme α-l-iduronidase (IDUA). In affected patients, the systemic accumulation of GAGs results in skeletal dysplasia, neurological degeneration, multiple organ dysfunction, and early death. Current therapies, including enzyme replacement and bone marrow transplant, improve life expectancy but the benefits to skeletal and neurological phenotypes are limited. In this study, we tested the therapeutic efficacy of liver-directed transplantation of a placental stem cell, which possesses multilineage differentiation potential, low immunogenicity, and high lysosomal enzyme activity. Unfractionated human amniotic epithelial cells (hAECs) were transplanted directly into the liver of immunodeficient Idua knockout mouse neonates. The hAECs engraftment was immunohistochemically confirmed with anti-human mitochondria staining. Enzyme activity assays indicated that hAECs transplantation restored IDUA function in the liver and significantly decreased urinary GAG excretion. Histochemical and micro-computed tomography analyses revealed reduced GAG deposition in the phalanges joints and composition/morphology improvement of cranial and facial bones. Neurological assessment in the hAEC treated mice showed significant improvement of sensorimotor coordination in the hAEC treated mice compared to untreated mice. Results confirm that partial liver cell replacement with placental stem cells can provide long-term (>20 weeks) and systemic restoration of enzyme function, and lead to significant phenotypic improvement in the MPS1 mouse model. This preclinical data indicate that liver-directed placental stem cell transplantation may improve skeletal and neurological phenotypes of MPS1 patients. Stem Cells Translational Medicine 2017;6:1583-1594. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of Alpha

Atypical onset of bicalutamide-induced liver injury.

PubMed

Yun, Gee Young; Kim, Seok Hyun; Kim, Seok Won; Joo, Jong Seok; Kim, Ju Seok; Lee, Eaum Seok; Lee, Byung Seok; Kang, Sun Hyoung; Moon, Hee Seok; Sung, Jae Kyu; Lee, Heon Young; Kim, Kyung Hee

2016-04-21

Anti-androgen therapy is the leading treatment for advanced prostate cancer and is commonly used for neoadjuvant or adjuvant treatment. Bicalutamide is a non-steroidal anti-androgen, used during the initiation of androgen deprivation therapy along with a luteinizing hormone-releasing hormone agonist to reduce the symptoms of tumor-related flares in patients with advanced prostate cancer. As side effects, bicalutamide can cause fatigue, gynecomastia, and decreased libido through competitive androgen receptor blockade. Additionally, although not as common, drug-induced liver injury has also been reported. Herein, we report a case of hepatotoxicity secondary to bicalutamide use. Typically, bicalutamide-induced hepatotoxicity develops after a few days; however, in this case, hepatic injury occurred 5 mo after treatment initiation. Based on this rare case of delayed liver injury, we recommend careful monitoring of liver function throughout bicalutamide treatment for prostate cancer.

Maternal Nutrition Induces Pervasive Gene Expression Changes but No Detectable DNA Methylation Differences in the Liver of Adult Offspring

PubMed Central

Cannon, Matthew V.; Buchner, David A.; Hester, James; Miller, Hadley; Sehayek, Ephraim; Nadeau, Joseph H.; Serre, David

2014-01-01

Aims Epidemiological and animal studies have shown that maternal diet can influence metabolism in adult offspring. However, the molecular mechanisms underlying these changes remain poorly understood. Here, we characterize the phenotypes induced by maternal obesity in a mouse model and examine gene expression and epigenetic changes induced by maternal diet in adult offspring. Methods We analyzed genetically identical male mice born from dams fed a high- or low-fat diet throughout pregnancy and until day 21 postpartum. After weaning, half of the males of each group were fed a high-fat diet, the other half a low-fat diet. We first characterized the genome-wide gene expression patterns of six tissues of adult offspring - liver, pancreas, white adipose, brain, muscle and heart. We then measured DNA methylation patterns in liver at selected loci and throughout the genome. Results Maternal diet had a significant effect on the body weight of the offspring when they were fed an obesogenic diet after weaning. Our analyses showed that maternal diet had a pervasive effect on gene expression, with a pronounced effect in liver where it affected many genes involved in inflammation, cholesterol synthesis and RXR activation. We did not detect any effect of the maternal diet on DNA methylation in the liver. Conclusions Overall, our findings highlighted the persistent influence of maternal diet on adult tissue regulation and suggested that the transcriptional changes were unlikely to be caused by DNA methylation differences in adult liver. PMID:24594983

Saturated and Unsaturated Dietary Fats Differentially Modulate Ethanol-Induced Changes in Gut Microbiome and Metabolome in a Mouse Model of Alcoholic Liver Disease.

PubMed

Kirpich, Irina A; Petrosino, Joseph; Ajami, Nadim; Feng, Wenke; Wang, Yuhua; Liu, Yanlong; Beier, Juliane I; Barve, Shirish S; Yin, Xinmin; Wei, Xiaoli; Zhang, Xiang; McClain, Craig J

2016-04-01

Alcoholic liver disease (ALD) ranks among major causes of morbidity and mortality. Diet and crosstalk between the gut and liver are important determinants of ALD. We evaluated the effects of different types of dietary fat and ethanol on the gut microbiota composition and metabolic activity and the effect of these changes on liver injury in ALD. Compared with ethanol and a saturated fat diet (medium chain triglycerides enriched), an unsaturated fat diet (corn oil enriched) exacerbated ethanol-induced endotoxemia, liver steatosis, and injury. Major alterations in gut microbiota, including a reduction in Bacteroidetes and an increase in Proteobacteria and Actinobacteria, were seen in animals fed an unsaturated fat diet and ethanol but not a saturated fat diet and ethanol. Compared with a saturated fat diet and ethanol, an unsaturated fat diet and ethanol caused major fecal metabolomic changes. Moreover, a decrease in certain fecal amino acids was noted in both alcohol-fed groups. These data support an important role of dietary lipids in ALD pathogenesis and provide insight into mechanisms of ALD development. A diet enriched in unsaturated fats enhanced alcohol-induced liver injury and caused major fecal metagenomic and metabolomic changes that may play an etiologic role in observed liver injury. Dietary lipids can potentially serve as inexpensive interventions for the prevention and treatment of ALD. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Pregnane X receptor regulates the AhR/Cyp1A1 pathway and protects liver cells from benzo-[α]-pyrene-induced DNA damage.

PubMed

Cui, Hongmei; Gu, Xinsheng; Chen, Jingshu; Xie, Ying; Ke, Sui; Wu, Jing; Golovko, Andrei; Morpurgo, Benjamin; Yan, Chunhong; Phillips, Timothy D; Xie, Wen; Luo, Jianyuan; Zhou, Zhijun; Tian, Yanan

2017-06-05

Pregnane X receptor (PXR) plays an important role in protecting cells from mutagenic DNA damages induced by endogenous and exogenous toxicants. This protective function is often attributed to the PXR-regulated metabolic detoxification. Here we report a novel potential mechanism that PXR reduces benzo-[α]-pyrene(BaP)-induced DNA damage through inhibiting the transcriptional activity of aryl hydrocarbon receptor (AhR) which plays a pivotal role in the bioactivation of BaP. We have utilized three well-characterized cell lines, i.e. Hepa1c1c7, AhR +/+; Bpr lacks AhR obligatory partner ARNT; Tao, lacks AhR, to analyze pivotal role of AhR/ARNT complex in mediating the BaP-induced DNA damages using comet assay (single-cell gel electrophoresis). We found that PXR activation could significantly inhibit BaP-induced DNA damage in the HepG2 cells as well as mouse hepatocytes. Using PXR-null and wild type mouse hepatocytes we showed that PXR activation by pregnenolone 16α-carbonitrile (PCN) significantly inhibited BaP-induced DNA damage and this protective effect was abolished in PXR-null hepatocytes. Mechanistically, PXR activation inhibited expression of AhR-target genes for CYP1A1, CYP1B1 and CYP1A2 that are required for BaP biotransformation in cultured liver cells, or in the livers of C57BL/6J mice. Using an AhR-responsive reporter assay as well as chromatin immunoprecipitation assay we found that PXR activation transcriptionally represses AhR-regulated gene expression. Furthermore, we found that PXR directly bound AhR at its DNA-binding domain, and this association may play a role in preventing of the AhR from binding to its target genes as shown in the ChIP assay. Taken together, our study has revealed a novel mechanism by which PXR protects liver cells from BaP-induced DNA damage through inhibiting the BaP biotransformation. Copyright © 2017 Elsevier B.V. All rights reserved.

Metabolism of Ginger Component [6]-Shogaol in Liver Microsomes from Mouse, Rat, Dog, Monkey, and Human

PubMed Central

Chen, Huadong; Soroka, Dominique; Zhu, Yingdong; Sang, Shengmin

2013-01-01

Scope There are limited data on the metabolism of [6]-shogaol, a major bioactive component of ginger. This study demonstrates metabolism of [6]-shogaol in liver microsomes from mouse, rat, dog, monkey, and human. Methods and results The in vitro metabolism of [6]-shogaol was compared among five species using liver microsomes from mouse, rat, dog, monkey, and human. Following incubations with [6]-shogaol, three major reductive metabolites 1-(4'-hydroxy-3'-methoxyphenyl)-4-decen-3-ol (M6), 1-(4′-hydroxy-3′-methoxyphenyl)-decan-3-ol (M9), and 1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-one (M11), as well as two new oxidative metabolites (1E, 4E)-1-(4'-hydroxy-3'-methoxyphenyl)-deca-1,4-dien-3-one (M14) and (E)-1-(4'-hydroxy-3'-methoxyphenyl)-dec-1-en-3-one (M15) were found in all species. The kinetic parameters of M6 in liver microsomes from each respective species were quantified using Michaelis-Menten theory. A broad CYP-450 inhibitor, 1-aminobenzotriazole, precluded the formation of oxidative metabolites M14 and M15, and 18β-glycyrrhetinic acid, an aldo-keto reductase inhibitor, eradicated the formation of the reductive metabolites M6, M9, and M11 in all species. Metabolites M14 and M15 were tested for cancer cell growth inhibition and induction of apoptosis and both showed substantial activity, with M14 displaying greater potency than [6]-shogaol. Conclusion We conclude that [6]-shogaol is metabolized extensively in mammalian species mouse, rat, dog, monkey, and human, and that there are significant interspecies differences to consider when planning pre-clinical trials towards [6]-shogaol chemoprevention. PMID:23322474

Rhein Induces Oxidative Stress and Apoptosis in Mouse Blastocysts and Has Immunotoxic Effects during Embryonic Development.

PubMed

Huang, Chien-Hsun; Chan, Wen-Hsiung

2017-09-20

Rhein, a glucoside chemical compound found in a traditional Chinese medicine derived from the roots of rhubarb, induces cell apoptosis and is considered to have high potential as an antitumor drug. Several previous studies showed that rhein can inhibit cell proliferation and trigger mitochondria-related or endoplasmic reticulum (ER) stress-dependent apoptotic processes. However, the side effects of rhein on pre- and post-implantation embryonic development remain unclear. Here, we show that rhein has cytotoxic effects on blastocyst-stage mouse embryos and induces oxidative stress and immunotoxicity in mouse fetuses. Blastocysts incubated with 5-20 μM rhein showed significant cell apoptosis, as well as decreases in their inner cell mass cell numbers and total cell numbers. An in vitro development assay showed that rhein affected the developmental potentials of both pre- and post-implantation embryos. Incubation of blastocysts with 5-20 μM rhein was associated with increased resorption of post-implantation embryos and decreased fetal weight in an embryo transfer assay. Importantly, in an in vivo model, intravenous injection of dams with rhein (1, 3, and 5 mg/kg body weight/day) for four days resulted in apoptosis of blastocyst-stage embryos, early embryonic developmental injury, and decreased fetal weight. Intravenous injection of dams with 5 mg/kg body weight/day rhein significantly increased the total reactive oxygen species (ROS) content of fetuses and the transcription levels of antioxidant proteins in fetal livers. Additional work showed that rhein induced apoptosis through ROS generation, and that prevention of apoptotic processes effectively rescued the rhein-induced injury effects on embryonic development. Finally, the transcription levels of the innate-immunity related genes, CXCL1 , IL-1 β and IL-8 , were down-regulated in the fetuses of dams that received intravenous injections of rhein. These results collectively show that rhein has the potential to

Development of Short-term Molecular Thresholds to Predict Long-term Mouse Liver Tumor Outcomes: Phthalate Case Study

EPA Science Inventory

Short-term molecular profiles are a central component of strategies to model health effects of environmental chemicals. In this study, a 7 day mouse assay was used to evaluate transcriptomic and proliferative responses in the liver for a hepatocarcinogenic phthalate, di (2-ethylh...

Obeticholic acid protects against carbon tetrachloride-induced acute liver injury and inflammation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Da-Gang

The farnesoid X receptor (FXR) is a ligand-activated transcription factor that plays important roles in regulating bile acid homeostasis. The aim of the present study was to investigate the effects of obeticholic acid (OCA), a novel synthetic FXR agonist, carbon tetrachloride (CCl{sub 4})-induced acute liver injury. Mice were intraperitoneally injected with CCl{sub 4} (0.15 ml/kg). In CCl{sub 4} + OCA group, mice were orally with OCA (5 mg/kg) 48, 24 and 1 h before CCl{sub 4}. As expected, hepatic FXR was activated by OCA. Interestingly, OCA pretreatment alleviated CCl{sub 4}-induced elevation of serum ALT and hepatic necrosis. Moreover, OCA pretreatmentmore » inhibited CCl{sub 4}-induced hepatocyte apoptosis. Additional experiment showed that OCA inhibits CCl{sub 4}-induced hepatic chemokine gene Mcp-1, Mip-2 and Kc. Moreover, OCA inhibits CCl{sub 4}-induced hepatic pro-inflammatory gene Tnf-α and Il-1β. By contrast, OCA pretreatment elevated hepatic anti-inflammatory gene Il-4. Further analysis showed that OCA pretreatment inhibited hepatic IκB phosphorylation and blocked nuclear translocation of NF-κB p65 and p50 subunits during CCl{sub 4}-induced acute liver injury. In addition, OCA pretreatment inhibited hepatic Akt, ERK and p38 phosphorylation in CCl{sub 4}-induced acute liver injury. These results suggest that OCA protects against CCl{sub 4}-induced acute liver injury and inflammation. Synthetic FXR agonists may be effective antidotes for hepatic inflammation during acute liver injury. - Highlights: • OCA pretreatment activates hepatic FXR. • FXR activation protects against CCl{sub 4}-induced acute liver injury. • FXR activation inhibits hepatocyte apoptosis during CCl{sub 4}-induced liver injury. • FXR activation differentially regulates hepatic inflammatory genes. • Synthetic FXR agonists are effective antidotes for acute liver injury.« less

A multiplicity of factors contributes to selective RNA polymerase III occupancy of a subset of RNA polymerase III genes in mouse liver

PubMed Central

Canella, Donatella; Bernasconi, David; Gilardi, Federica; LeMartelot, Gwendal; Migliavacca, Eugenia; Praz, Viviane; Cousin, Pascal; Delorenzi, Mauro; Hernandez, Nouria; Hernandez, Nouria; Delorenzi, Mauro; Deplancke, Bart; Desvergne, Béatrice; Guex, Nicolas; Herr, Winship; Naef, Felix; Rougemont, Jacques; Schibler, Ueli; Deplancke, Bart; Guex, Nicolas; Herr, Winship; Guex, Nicolas; Andersin, Teemu; Cousin, Pascal; Gilardi, Federica; Gos, Pascal; Le Martelot, Gwendal; Lammers, Fabienne; Canella, Donatella; Gilardi, Federica; Raghav, Sunil; Fabbretti, Roberto; Fortier, Arnaud; Long, Li; Vlegel, Volker; Xenarios, Ioannis; Migliavacca, Eugenia; Praz, Viviane; Guex, Nicolas; Naef, Felix; Rougemont, Jacques; David, Fabrice; Jarosz, Yohan; Kuznetsov, Dmitry; Liechti, Robin; Martin, Olivier; Ross, Frederick; Sinclair, Lucas; Cajan, Julia; Krier, Irina; Leleu, Marion; Migliavacca, Eugenia; Molina, Nacho; Naldi, Aurélien; Rey, Guillaume; Symul, Laura; Guex, Nicolas; Naef, Felix; Rougemont, Jacques; Bernasconi, David; Delorenzi, Mauro; Andersin, Teemu; Canella, Donatella; Gilardi, Federica; Le Martelot, Gwendal; Lammers, Fabienne; Raghav, Sunil

2012-01-01

The genomic loci occupied by RNA polymerase (RNAP) III have been characterized in human culture cells by genome-wide chromatin immunoprecipitations, followed by deep sequencing (ChIP-seq). These studies have shown that only ∼40% of the annotated 622 human tRNA genes and pseudogenes are occupied by RNAP-III, and that these genes are often in open chromatin regions rich in active RNAP-II transcription units. We have used ChIP-seq to characterize RNAP-III-occupied loci in a differentiated tissue, the mouse liver. Our studies define the mouse liver RNAP-III-occupied loci including a conserved mammalian interspersed repeat (MIR) as a potential regulator of an RNAP-III subunit-encoding gene. They reveal that synteny relationships can be established between a number of human and mouse RNAP-III genes, and that the expression levels of these genes are significantly linked. They establish that variations within the A and B promoter boxes, as well as the strength of the terminator sequence, can strongly affect RNAP-III occupancy of tRNA genes. They reveal correlations with various genomic features that explain the observed variation of 81% of tRNA scores. In mouse liver, loci represented in the NCBI37/mm9 genome assembly that are clearly occupied by RNAP-III comprise 50 Rn5s (5S RNA) genes, 14 known non-tRNA RNAP-III genes, nine Rn4.5s (4.5S RNA) genes, and 29 SINEs. Moreover, out of the 433 annotated tRNA genes, half are occupied by RNAP-III. Transfer RNA gene expression levels reflect both an underlying genomic organization conserved in dividing human culture cells and resting mouse liver cells, and the particular promoter and terminator strengths of individual genes. PMID:22287103

Liver natural killer cells: subsets and roles in liver immunity

PubMed Central

Peng, Hui; Wisse, Eddie; Tian, Zhigang

2016-01-01

The liver represents a frontline immune organ that is constantly exposed to a variety of gut-derived antigens as a result of its unique location and blood supply. With a predominant role in innate immunity, the liver is enriched with various innate immune cells, among which natural killer (NK) cells play important roles in host defense and in maintaining immune balance. Hepatic NK cells were first described as ‘pit cells' in the rat liver in the 1970s. Recent studies of NK cells in mouse and human livers have shown that two distinct NK cell subsets, liver-resident NK cells and conventional NK (cNK) cells, are present in this organ. Here, we review liver NK cell subsets in different species, revisiting rat hepatic pit cells and highlighting recent progress related to resident NK cells in mouse and human livers, and also discuss the dual roles of NK cells in liver immunity. PMID:26639736

[Influence of bear bile on rat hepatocarcinoma induced by diethylnitrosamine].

PubMed

Zhou, Jian-Yin; Yin, Zhen-Yu; Wang, Sheng-Yu; Yan, Jiang-Hua; Zhao, Yi-Lin; Wu, Duan; Liu, Zheng-Jin; Zhang, Sheng; Wang, Xiao-Min

2012-11-01

To investigate the influence of bear bile on rat hepatocarcinoma induced by diethylnitrosamine (DEN), a total of 40 rats were randomly divided into 4 groups: normal control group, model group, and two bear bile treatment groups. The rat liver cancer model was induced by breeding with water containing 100 mg x L(-1) DEN for 14 weeks. The rats of the bear bile groups received bear bile powder (200 or 400 mg x kg(-1)) orally 5 times per week for 18 weeks. The general condition and the body weight of rats were examined every day. After 18 weeks the activities of serum alanine transaminase (ALT), aspartate transaminase (AST) and total bilirubin (TBIL) were detected. Meanwhile, the pathological changes of liver tissues were observed after H&E staining. The expression of proliferative cell nuclear antigen (PCNA) and a-smooth muscle actin (alpha-SMA) in liver tissue were detected by immunohistochemical method. After 4 weeks the body weights of rats in normal group were significantly more than that in other groups (P < 0.05); and that in the two bile groups was significantly more than that in the model group. Compared with normal group, the level of serum glutamic-pyruvic transaminase and total bilirubin increased significantly in other groups; compared with model group, these two indexes decreased significantly in two bile groups. Hepatocellular carcinoma occurred in all rats except for normal group; there were classic cirrhosis and cancer in model group while there were mild cirrhosis and high differentiation in two bile groups. There were almost no expressions of PCNA and alpha-SMA in normal group while there were high expressions in model group; the two bile groups had some expressions but were inferior to the model group, and alpha-SMA reduced markedly. It indicated that bear bile restrained the development of liver cancer during DEN inducing rat hepatocarcinoma, which may be related to its depressing hepatic stellate cell activation and relieving hepatic lesion and

Inactivated Orf virus (Parapoxvirus ovis) elicits antifibrotic activity in models of liver fibrosis.

PubMed

Nowatzky, Janina; Knorr, Andreas; Hirth-Dietrich, Claudia; Siegling, Angela; Volk, Hans-Dieter; Limmer, Andreas; Knolle, Percy; Weber, Olaf

2013-05-01

Inactivated Orf virus (ORFV, Parapoxvirus ovis) demonstrates strong antiviral activity in animal models including a human hepatitis B virus (HBV)-transgenic mouse. In addition, expression of interferon (IFN)-γ and interleukin-10 (IL-10) was induced after administration of inactivated ORFV in these mice. IFN-γ and IL-10 are known to elicit antifibrotic activity. We therefore aimed to study antifibrotic activity of inactivated ORFV in models of liver fibrosis. We characterized ORFV-induced hepatic cytokine expression in rats. We then studied ORFV in two models of liver fibrosis in rats, pig serum-induced liver fibrosis and carbon tetrachloride (CCL4 )-induced liver fibrosis. ORFV induced hepatic expression of IFN-γ and IL-10 in rats. ORFV mediated antifibrotic activity when administrated concomitantly with the fibrosis-inducing agents in both models of liver fibrosis. Importantly, when CCL4 -induced liver fibrosis was already established, ORFV application still showed significant antifibrotic activity. In addition, we were able to demonstrate a direct antifibrotic effect of ORFV on stellate cells. These results establish a potential novel antifibrotic therapeutic approach that not only prevents but also resolves established liver fibrosis. Further studies are required to unravel the details of the mechanisms involved. © 2012 The Japan Society of Hepatology.

Description of histopathological changes induced by the venom of the Persian Gulf Lionfish (Pterois russelli) in a mouse model of multiorgan toxicity.

PubMed

Memar, Bahareh; Jamili, Shahla; Shahbazzadeh, Delavar; Pooshang Bagheri, Kamran

2016-11-01

Pterois russelli is a venomous fish belongs to Scorpaenidae family. Envenomation by the Persian Gulf lionfish is associated with local pain, marked inflammation and local heat. The present study was aimed to document the histopathological changes in liver, heart, lung, kidney and alterations in release of critical enzymes such as LDH, CK. AST, ALT and ALP induced by the administration of various doses of P. russelli venom in a mouse model. LD50 of venom was determined by intravenous injection in Balb/c mice. Histopathological alterations of lung, liver, heart and kidney following injection of one LD50, 1/2 and 1/3 LD50 doses of the venom were evaluated. Simultaneously, release of LDH, CK, AST, ALT and ALP were measured in serum following administration of 1/2 and1/3 LD50 doses of the venom too. LD50 was calculated as 10.5 mg/kg. The level of all enzymes were increased after 3 h and significantly raised after 24 h and rapidly reduced after 48 h. Histological studies showed that one LD50 and 1/2 LD50 doses of the venom induced significant histological alterations in the lungs, liver, heart and kidneys including congestion, hemorrhage, necrosis, apoptosis, edema, and infiltration of inflammatory cells. The results indicate that the venom of P. russelli has nephrotoxic, hepatotoxic, cardiotoxic and pneumotoxic effects in mouse model. Among four examined vital organs, the highest critical events were seen in liver. The findings are useful to give new insight in the fish's venom studies. Gathering the data resulted from this study together will be directed us toward a good aspect concerning the toxicity of potential therapeutic molecules in the venom of lionfish. Copyright © 2016 Elsevier Ltd. All rights reserved.

Flow cytometric method for scoring rat liver micronuclei with simultaneous assessments of hepatocyte proliferation.

PubMed

Avlasevich, Svetlana L; Khanal, Sumee; Singh, Priyanka; Torous, Dorothea K; Bemis, Jeffrey C; Dertinger, Stephen D

2018-04-01

The current report describes a newly devised method for automatically scoring the incidence of rat hepatocyte micronuclei (MNHEP) via flow cytometry, with concurrent assessments of hepatocyte proliferation-frequency of Ki-67-positive nuclei, and the proportion of polyploid nuclei. Proof-of-concept data are provided from experiments performed with 6-week old male Crl:CD(SD) rats exposed to diethylnitrosamine (DEN) or quinoline (QUIN) for 3 or 14 consecutive days. Non-perfused liver tissue was collected 4 days after cessation of treatment in the case of 3-day studies, or 1 day after last administration in the case of 14-day studies for processing and flow cytometric analysis. In addition to livers, blood samples were collected one day after final treatment for micronucleated reticulocyte (MN-RET) measurements. Dose-dependent increases in MNHEP, Ki-67-positive nuclei, and polyploidy were observed in 3- and 14-day DEN studies. Both treatment schedules resulted in elevated %MNHEP for QUIN-exposed rats, and while cell proliferation effects were subtle, appreciable increases to normalized liver weights were observed. Whereas DEN caused markedly higher %MNHEP when exposure was extended to two weeks, QUIN-induced MNHEP were slightly increased with protracted dosing. Parallel microscopy-based MNHEP frequencies were highly correlated with flow cytometry-based measurements (four study/aggregate R 2  = 0.80). No increases in MN-RET were seen in any of the four studies. Collectively, these results suggest liver micronuclei are amenable to an automated scoring technique that provides objective analyses and higher information content relative to conventional microscopy. Additional work is needed to expand the number and types of chemicals tested, identify the most advantageous treatment schedules, and test the transferability of the method. Environ. Mol. Mutagen. 59:176-187, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Paeoniflorin regulates macrophage activation in dimethylnitrosamine-induced liver fibrosis in rats

PubMed Central

2012-01-01

Background Macrophages in other organs (e.g. kidneys, lungs, and spleen, et. al) have rarely been reported in the development of liver fibrosis. Therefore, it is important to investigate macrophage activation in the main organs in liver fibrosis. We investigated the potential antifibrogenic effects of paeoniflorin (PF) in a dimethylnitrosamine (DMN)-induced rat model with special focus on inhibiting macrophage activation in the main organs. Methods Rat hepatic fibrosis was induced by treatment with DMN three times weekly over a 4-week period. DMN rats were treated with water, PF, or gadolinium chloride (GdCl3) from the beginning of the 3rd week. The expression of CD68, marker of macrophage, was investigated using immunohistochemical, real-time PCR, and western blot analysis. Results Hepatic hydroxyproline content markedly decreased and histopathology improved in the DMN-PF rats. Expression of desmin and collagen 1 decreased notably in DMN-PF liver. CD68 expression in the liver, spleen and kidney increased markedly after 2 weeks but decreased in DMN-water rats. PF and GdCl3 decreased CD68 expression in the liver and spleen and there was no effect on kidney. CD68 expression in the lung increased gradually during the course of DMN-induced liver fibrosis, and PF inhibited CD68 expression in the lung significantly while GdCl3 increased CD68 markedly. Expression of tumor necrosis factor (TNF-α) was decreased significantly by GdCl3 in the liver, as revealed by real-time PCR analysis. However, GdCl3 could not decrease TNF-α level in the serum by enzyme linked immunosorbent assay (ELISA). Conclusions Macrophage activation was disrupted in the liver, spleen, lung and kidney during development of DMN-induced liver fibrosis. PF administration attenuated DMN-induced liver fibrosis at least in part by regulating macrophage disruption in the main organs. PMID:23237422

Fialuridine induces acute liver failure in chimeric TK-NOG mice: a model for detecting hepatic drug toxicity prior to human testing.

PubMed

Xu, Dan; Nishimura, Toshi; Nishimura, Sachiko; Zhang, Haili; Zheng, Ming; Guo, Ying-Ying; Masek, Marylin; Michie, Sara A; Glenn, Jeffrey; Peltz, Gary

2014-04-01

Seven of 15 clinical trial participants treated with a nucleoside analogue (fialuridine [FIAU]) developed acute liver failure. Five treated participants died, and two required a liver transplant. Preclinical toxicology studies in mice, rats, dogs, and primates did not provide any indication that FIAU would be hepatotoxic in humans. Therefore, we investigated whether FIAU-induced liver toxicity could be detected in chimeric TK-NOG mice with humanized livers. Control and chimeric TK-NOG mice with humanized livers were treated orally with FIAU 400, 100, 25, or 2.5 mg/kg/d. The response to drug treatment was evaluated by measuring plasma lactate and liver enzymes, by assessing liver histology, and by electron microscopy. After treatment with FIAU 400 mg/kg/d for 4 d, chimeric mice developed clinical and serologic evidence of liver failure and lactic acidosis. Analysis of liver tissue revealed steatosis in regions with human, but not mouse, hepatocytes. Electron micrographs revealed lipid and mitochondrial abnormalities in the human hepatocytes in FIAU-treated chimeric mice. Dose-dependent liver toxicity was detected in chimeric mice treated with FIAU 100, 25, or 2.5 mg/kg/d for 14 d. Liver toxicity did not develop in control mice that were treated with the same FIAU doses for 14 d. In contrast, treatment with another nucleotide analogue (sofosbuvir 440 or 44 mg/kg/d po) for 14 d, which did not cause liver toxicity in human trial participants, did not cause liver toxicity in mice with humanized livers. FIAU-induced liver toxicity could be readily detected using chimeric TK-NOG mice with humanized livers, even when the mice were treated with a FIAU dose that was only 10-fold above the dose used in human participants. The clinical features, laboratory abnormalities, liver histology, and ultra-structural changes observed in FIAU-treated chimeric mice mirrored those of FIAU-treated human participants. The use of chimeric mice in preclinical toxicology studies could improve

Drug-Induced Liver Toxicity and Prevention by Herbal Antioxidants: An Overview

PubMed Central

Singh, Divya; Cho, William C.; Upadhyay, Ghanshyam

2016-01-01

The liver is the center for drug and xenobiotic metabolism, which is influenced most with medication/xenobiotic-mediated toxic activity. Drug-induced hepatotoxicity is common and its actual frequency is hard to determine due to underreporting, difficulties in detection or diagnosis, and incomplete observation of exposure. The death rate is high, up to about 10% for drug-induced liver damage. Endorsed medications represented >50% of instances of intense liver failure in a study from the Acute Liver Failure Study Group of the patients admitted in 17 US healing facilities. Albeit different studies are accessible uncovering the mechanistic aspects of medication prompted hepatotoxicity, we are in the dilemma about the virtual story. The expanding prevalence and effectiveness of Ayurveda and natural products in the treatment of various disorders led the investigators to look into their potential in countering drug-induced liver toxicity. Several natural products have been reported to date to mitigate the drug-induced toxicity. The dietary nature and less adverse reactions of the natural products provide them an extra edge over other candidates of supplementary medication. In this paper, we have discussed the mechanism involved in drug-induced liver toxicity and the potential of herbal antioxidants as supplementary medication. PMID:26858648

Analyses of cell surface molecules on hepatic stem/progenitor cells in mouse fetal liver.

PubMed

Kakinuma, Sei; Ohta, Haruhiko; Kamiya, Akihide; Yamazaki, Yuji; Oikawa, Tsunekazu; Okada, Ken; Nakauchi, Hiromitsu

2009-07-01

Hepatic stem/progenitor cells possess active proliferative ability and the capacity for differentiation into hepatic and cholangiocytic lineages. Our group and others have shown that a prospectively defined population in mid-gestational fetal liver contains hepatic stem/progenitor cells. However, the phenotypes of such cells are incompletely elucidated. We analyzed the profile of cell-surface molecules on primary hepatic stem/progenitor cells. Expression of cell surface molecules on primary hepatic stem/progenitor cells in mouse mid-gestational fetal liver was analyzed using flow cytometric multicolor analyses and colony-formation assays. The potential of the cells for liver repopulation was examined by transplantation assay. We found that CD13 (aminopeptidase N) was detected on the cells of the previously reported (Dlk/Pref-1(+)) hepatic stem/progenitor fraction. Colony-formation assays revealed that the CD13(+) fraction, compared with the Dlk(+) fraction, of non-hematopoietic cells in fetal liver was enriched in hepatic stem/progenitor cells. Transplantation assay showed the former fraction exhibited repopulating potential in regenerating liver. Moreover, flow cytometric analysis for over 90 antigens demonstrated enrichment of hepatic stem/progenitor cells using several positive selection markers, including (hitherto unknown) CD13, CD73, CD106, and CD133. Our data indicated that CD13 is a positive selection marker for hepatic stem/progenitor cells in mid-gestational fetal liver.

Designing of mouse model: a new approach for studying sulphur mustard-induced skin lesions.

PubMed

Lomash, Vinay; Deb, Utsab; Rai, Renuka; Jadhav, Sunil E; Vijayaraghavan, R; Pant, S C

2011-08-01

This study was planned to design a mouse model for studying sulphur mustard (SM)-induced skin injury. SM was applied dermally at dose of 5 or 10 mg kg(-1) in polyethyleneglycol-300 (PEG-300) or dimethylsulphoxide (DMSO) or acetone once. The changes in body weight, organ body weight indices (OBWI) and haematological and oxidative stress parameters were investigated over a period of 3-7 days and supported by histopathological observations. Exposure to SM in PEG-300 or DMSO resulted in a significant depletion in body weight, OBWI, hepatic glutathione (GSH) and elevation in hepatic lipid peroxidation, without affecting the blood GSH and hepatic oxidised glutathione (GSSG) levels. Interestingly, no aforesaid change was observed after dermal application of SM diluted in acetone. These biochemical changes were supported by the histological observations, which revealed pronounced toxic effect and damage to liver, kidney and spleen after dermal application of SM diluted in PEG-300 or DMSO. The skin showed similar microscopic changes after dermal application of SM in all the three diluents, however; the severity of lesions was found to be time and dose dependent. It can be concluded that dermal exposure of SM diluted in acetone can be used to mimic SM-induced skin toxicity without systemic toxicity in a mouse model. Copyright © 2010 Elsevier Ltd and ISBI. All rights reserved.

Heparanase and macrophage interplay in the onset of liver fibrosis.

PubMed

Secchi, Maria Francesca; Crescenzi, Marika; Masola, Valentina; Russo, Francesco Paolo; Floreani, Annarosa; Onisto, Maurizio

2017-11-02

The heparan sulfate endoglycosidase heparanase (HPSE) is involved in tumor growth, chronic inflammation and fibrosis. Since a role for HPSE in chronic liver disease has not been demonstrated to date, the current study was aimed at investigating the involvement of HPSE in the pathogenesis of chronic liver injury. Herein, we revealed that HPSE expression increased in mouse livers after carbon tetrachloride (CCl 4 )-mediated chronic induction of fibrosis, but with a trend to decline during progression of the disease. In mouse fibrotic liver tissues HPSE immunostaining was restricted in necro-inflammatory areas, co-localizing with F4/80 macrophage marker and TNF-α. TNF-α treatment induced HPSE expression as well as HPSE secretion in U937 macrophages. Moreover, macrophage-secreted HPSE regulated the expression of α-SMA and fibronectin in hepatic stellate LX-2 cells. Finally, HPSE activity increased in the plasma of patients with liver fibrosis but it inversely correlated with liver stiffness. Our results suggest the involvement of HPSE in early phases of reaction to liver damage and inflammatory macrophages as an important source of HPSE. HPSE seems to play a key role in the macrophage-mediated activation of hepatic stellate cells (HSCs), thus suggesting that HPSE targeting could be a new therapeutic option in the treatment of liver fibrosis.

The role of renal proximal tubule P450 enzymes in chloroform-induced nephrotoxicity: Utility of renal specific P450 reductase knockout mouse models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Senyan; Wadsworth Center, New York State Department of Health, and School of Public Health, State University of New York, Albany, NY 12201; Yao, Yunyi

The kidney is a primary target for numerous toxic compounds. Cytochrome P450 enzymes (P450) are responsible for the metabolic activation of various chemical compounds, and in the kidney are predominantly expressed in proximal tubules. The aim of this study was to test the hypothesis that renal proximal tubular P450s are critical for nephrotoxicity caused by chemicals such as chloroform. We developed two new mouse models, one having proximal tubule-specific deletion of the cytochrome P450 reductase (Cpr) gene (the enzyme required for all microsomal P450 activities), designated proximal tubule-Cpr-null (PTCN), and the other having proximal tubule-specific rescue of CPR activity withmore » the global suppression of CPR activity in all extra-proximal tubular tissues, designated extra-proximal tubule-Cpr-low (XPT-CL). The PTCN, XPT-CL, Cpr-low (CL), and wild-type (WT) mice were treated with a single oral dose of chloroform at 200 mg/kg. Blood, liver and kidney samples were obtained at 24 h after the treatment. Renal toxicity was assessed by measuring BUN and creatinine levels, and by pathological examination. The blood and tissue levels of chloroform were determined. The severity of toxicity was less in PTCN and CL mice, compared with that of WT and XPT-CL mice. There were no significant differences in chloroform levels in the blood, liver, or kidney, between PTCN and WT mice, or between XPT-CL and CL mice. These findings indicate that local P450-dependent activities play an important role in the nephrotoxicity induced by chloroform. Our results also demonstrate the usefulness of these novel mouse models for studies of chemical-induced kidney toxicity. - Highlights: • New mouse models were developed with varying P450 activities in the proximal tubule. • These mouse models were treated with chloroform, a nephrotoxicant. • Studies showed the importance of local P450s in chloroform-induced nephrotoxicity.« less

FGF7 is a functional niche signal required for stimulation of adult liver progenitor cells that support liver regeneration

PubMed Central

Takase, Hinako M.; Itoh, Tohru; Ino, Seitaro; Wang, Ting; Koji, Takehiko; Akira, Shizuo; Takikawa, Yasuhiro; Miyajima, Atsushi

2013-01-01

The liver is a unique organ with a remarkably high potential to regenerate upon injuries. In severely damaged livers where hepatocyte proliferation is impaired, facultative liver progenitor cells (LPCs) proliferate and are assumed to contribute to regeneration. An expansion of LPCs is often observed in patients with various types of liver diseases. However, the underlying mechanism of LPC activation still remains largely unknown. Here we show that a member of the fibroblast growth factor (FGF) family, FGF7, is a critical regulator of LPCs. Its expression was induced concomitantly with LPC response in the liver of mouse models as well as in the serum of patients with acute liver failure. Fgf7-deficient mice exhibited markedly depressed LPC expansion and higher mortality upon toxin-induced hepatic injury. Transgenic expression of FGF7 in vivo led to the induction of cells with characteristics of LPCs and ameliorated hepatic dysfunction. We revealed that Thy1+ mesenchymal cells produced FGF7 and appeared in close proximity to LPCs, implicating a role for those cells as the functional LPC niche in the regenerating liver. These findings provide new insights into the cellular and molecular basis for LPC regulation and identify FGF7 as a potential therapeutic target for liver diseases. PMID:23322300

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

PubMed

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

2017-02-26

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. Copyright © 2017 Elsevier Inc. All rights reserved.

Betanin attenuates paraquat-induced liver toxicity through a mitochondrial pathway.

PubMed

Han, Junyan; Zhang, Zongju; Yang, Shaobin; Wang, Jun; Yang, Xuelian; Tan, Dehong

2014-08-01

We attempted to determine whether betanin (from natural pigments) that has anti-oxidant properties would be protective against paraquat-induced liver injury in Sprague-Dawley rats. Paraquat was injected intraperitoneally into rats to induce liver toxicity. The rats were randomly divided into four groups: a control group, a paraquat group, and two groups that received betanin at doses of 25 and 100mg/kg/day three days before and two days after they were administered paraquat. We evaluated liver histopathology, serum liver enzymatic activities, oxidative stress, cytochrome P450 (CYP) 3A2 mRNA expression, and mitochondrial damage. The rats that were injected with paraquat incurred liver injury, evidenced by histological changes and elevated serum aspartate aminotransferase and alanine aminotransferase levels; paraquat also led to oxidative stress, an increase of cytochrome P450 3A2 mRNA expression, and mitochondrial damage, indicated by mitochondrial membrane swelling, reduced mitochondrial cytochrome C, and apoptosis-inducing factor protein levels. Pathological damage and all of the above mentioned markers were lesser in the animals treated with betanin than in those who received paraquat alone. Betanin had a protective effect against paraquat-induced liver damage in rats. The mechanism of the protection appears to be the inhibition of CYP 3A2 expression and protection of mitochondria. Copyright © 2014 Elsevier Ltd. All rights reserved.

New evidence for the therapeutic potential of curcumin to treat nonalcoholic fatty liver disease in humans.

PubMed

Inzaugarat, María Eugenia; De Matteo, Elena; Baz, Placida; Lucero, Diego; García, Cecilia Claudia; Gonzalez Ballerga, Esteban; Daruich, Jorge; Sorda, Juan Antonio; Wald, Miriam Ruth; Cherñavsky, Alejandra Claudia

2017-01-01

The immune system acts on different metabolic tissues that are implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Leptin and linoleic acid have the ability to potentially affect immune cells, whereas curcumin is a known natural polyphenol with antioxidant and anti-inflammatory properties. This study was designed to evaluate the pro-inflammatory and pro-oxidant effects of leptin and linoleic acid on immune cells from patients with NAFLD and to corroborate the modulatory effects of curcumin and its preventive properties against the progression of NAFLD using a high-fat diet (HFD)-induced NAFLD/nonalcoholic steatohepatitis mouse model. The ex vivo experiments showed that linoleic acid increased the production of reactive oxygen species in monocytes and liver macrophages, whereas leptin enhanced tumor necrosis factor-α (TNF-α) production in monocytes and interferon-γ production in circulating CD4+ cells. Conversely, oral administration of curcumin prevented HFD-induced liver injury, metabolic alterations, intrahepatic CD4+ cell accumulation and the linoleic acid- and leptin- induced pro-inflammatory and pro-oxidant effects on mouse liver macrophages. Our findings provide new evidence for the therapeutic potential of curcumin to treat human NAFLD. However, the development of a preventive treatment targeting human circulating monocytes and liver macrophages as well as peripheral and hepatic CD4+ cells requires additional research.

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

PubMed

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 < 0.05). The decrease of EndMT in cirrhotic livers correlated with a significant decrease in liver fibrosis ( P < 0.05) and an improvement in the vascular disorganization rate ( P < 0.05). We demonstrated the acquisition of the EndMT phenotype by a subpopulation of endothelial cells from cirrhotic 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

Metabolism of ginger component [6]-shogaol in liver microsomes from mouse, rat, dog, monkey, and human.

PubMed

Chen, Huadong; Soroka, Dominique; Zhu, Yingdong; Sang, Shengmin

2013-05-01

There are limited data on the metabolism of [6]-shogaol (6S), a major bioactive component of ginger. This study demonstrates metabolism of 6S in liver microsomes from mouse, rat, dog, monkey, and human. The in vitro metabolism of 6S was compared among five species using liver microsomes from mouse, rat, dog, monkey, and human. Following incubations with 6S, three major reductive metabolites 1-(4'-hydroxy-3'-methoxyphenyl)-4-decen-3-ol (M6), 1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-ol (M9), and 1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-one (M11), as well as two new oxidative metabolites (1E,4E)-1-(4'-hydroxy-3'-methoxyphenyl)-deca-1,4-dien-3-one (M14) and (E)-1-(4'-hydroxy-3'-methoxyphenyl)-dec-1-en-3-one (M15) were found in all species. The kinetic parameters of M6 in liver microsomes from each respective species were quantified using Michaelis-Menten theory. A broad CYP-450 inhibitor, 1-aminobenzotriazole, precluded the formation of oxidative metabolites, M14 and M15, and 18β-glycyrrhetinic acid, an aldo-keto reductase inhibitor, eradicated the formation of the reductive metabolites M6, M9, and M11 in all species. Metabolites M14 and M15 were tested for cancer cell growth inhibition and induction of apoptosis and both showed substantial activity, with M14 displaying greater potency than 6S. We conclude that 6S is metabolized extensively in mammalian species mouse, rat, dog, monkey, and human, and that there are significant interspecies differences to consider when planning preclinical trials toward 6S chemoprevention. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

PubMed

Huang, Chun; Li, Runqin; Zhang, Yinglin; Gong, Jianping

2017-10-01

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. 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. 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. 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.

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

PubMed Central

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

Monitoring Cyp2b10 mRNA expression at cessation of 2-year carcinogenesis bioassay in mouse liver provides evidence for a carcinogenic mechanism devoid of human relevance: The dalcetrapib experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoflack, J-C.; Mueller, L., E-mail: Lutz.Mueller@roche.com; Fowler, S.

2012-03-15

Introduction: Dalcetrapib is a cholesteryl ester transfer protein (CETP) modulator in clinical assessment for cardiovascular outcome benefits. In compliance with regulatory requirements, dalcetrapib was evaluated in rodent 2-year carcinogenesis bioassays. In the mouse bioassay, male mice demonstrated increased liver weight and statistically increased incidences of hepatocellular adenoma/carcinoma. Hepatic cytochrome p450 (Cyp) 2b10 mRNA induction and increased Cyp2b10 enzyme activity signify activation of hepatic nuclear receptor constitutive androstane receptor (CAR), a widely established promoter of rodent-specific hepatic tumors. We therefore monitored hepatic Cyp2b10 mRNA and its enzyme activity in a subset of dalcetrapib-treated male mice from the bioassay. Methods: Liver samplesmore » were obtained from ∼ 1/3 of male mice from each dose group including vehicle-controls (mean and earliest study day of death 678 and 459 respectively). Quantitative real time PCR (qRT-PCR) was performed to determine Cyp2b10 mRNA expression and Cyp1a-, Cyp2b10- and Cyp3a-selective activities were monitored. Results: Cyp2b10 mRNA was strongly induced by dalcetrapib with an expected wide inter-individual variation (5–1421-fold). Group average fold-induction versus vehicle-controls showed a dose-related increase from 48-fold (250 mg/kg/day) to 160-fold (750 mg/kg/day), which declined slightly at 2000 mg/kg/day (97-fold). Cyp enzyme activities showed approximate doubling of total Cyp P450 content per milligram protein and a 9-fold increase in Cyp2b10-selective pentoxyresorufin O-dealkylase activity (750 mg/kg/day). Discussion: These data from hepatic Cyp2b10 monitoring are strongly suggestive of CAR activation by dalcetrapib, a mechanism devoid of relevance towards hepatocarcinogenesis in humans; results show feasibility of Cyp2b10 as a surrogate marker for this mechanism at cessation of a carcinogenesis bioassay. -- Highlights: ► Liver tumors were induced in male mice by

Systematic revelation of the protective effect and mechanism of Cordycep sinensis on diethylnitrosamine-induced rat hepatocellular carcinoma with proteomics.

PubMed

Wang, Pei-Wen; Hung, Yu-Chiang; Li, Wen-Tai; Yeh, Chau-Ting; Pan, Tai-Long

2016-09-13

Cordyceps sinensis (C. sinensis) has been reported to treat liver diseases. Here, we investigated the inhibitory effect of C. sinensis on hepatocarcinoma in a diethylnitrosamine (DEN)-induced rat model with functional proteome tools.In the DEN-exposed group, levels of serum alanine aminotransferase and aspartate aminotransferase were increased while C. sinensis application remarkably inhibited the activities of these enzymes. Histopathological analysis also indicated that C. sinensis could substantially restore hypertrophic hepatocytes caused by DEN, suggesting that C. sinensis is effective in preventing DEN-induced hepatocarcinogenesis.We therefore comprehensively delineated the global protein alterations using a proteome platform. The most meaningful changes were found among proteins involved in oxidative stress and detoxification. Meanwhile, C. sinensis application could attenuate the carbonylation level of several enzymes as well as chaperone proteins. Network analysis implied that C. sinensis could obviously alleviate hepatocarcinoma via modulating redox imbalance, protein ubiquitination and tumor growth-associated transcription factors.Our findings provide new insight into the potential effects of C. sinensis in preventing carcinogenesis and might help in developing novel therapeutic strategies against chemical-induced hepatocarcinoma.

Systematic revelation of the protective effect and mechanism of Cordycep sinensis on diethylnitrosamine-induced rat hepatocellular carcinoma with proteomics

PubMed Central

Wang, Pei-Wen; Hung, Yu-Chiang; Li, Wen-Tai; Yeh, Chau-Ting; Pan, Tai-Long

2016-01-01

Cordyceps sinensis (C. sinensis) has been reported to treat liver diseases. Here, we investigated the inhibitory effect of C. sinensis on hepatocarcinoma in a diethylnitrosamine (DEN)-induced rat model with functional proteome tools. In the DEN-exposed group, levels of serum alanine aminotransferase and aspartate aminotransferase were increased while C. sinensis application remarkably inhibited the activities of these enzymes. Histopathological analysis also indicated that C. sinensis could substantially restore hypertrophic hepatocytes caused by DEN, suggesting that C. sinensis is effective in preventing DEN-induced hepatocarcinogenesis. We therefore comprehensively delineated the global protein alterations using a proteome platform. The most meaningful changes were found among proteins involved in oxidative stress and detoxification. Meanwhile, C. sinensis application could attenuate the carbonylation level of several enzymes as well as chaperone proteins. Network analysis implied that C. sinensis could obviously alleviate hepatocarcinoma via modulating redox imbalance, protein ubiquitination and tumor growth–associated transcription factors. Our findings provide new insight into the potential effects of C. sinensis in preventing carcinogenesis and might help in developing novel therapeutic strategies against chemical-induced hepatocarcinoma. PMID:27531890

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

NASA Astrophysics Data System (ADS)

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.

Drug-induced Liver Disease in Patients with Diabetes Mellitus.

PubMed

Iryna, Klyarytskaya; Helen, Maksymova; Elena, Stilidi

2015-01-01

The study presented here was accomplished to assess the course of drug-induced liver diseases in patient's rheumatoid arthritis receiving long-term methotrexate therapy. Diabetes mellitus was revealed as the most significant risk factor. The combination of diabetes mellitus with other risk factors (female sex) resulted in increased hepatic fibrosis, degree of hepatic encephalopathy and reduction of hepatic functions. The effectiveness and safety of ursodeoxycholic acid and cytolytic type-with S-Adenosyl methionine was also evaluated. 13C-MBT: 13C-methacetin breath test; ALT: alanine aminotransferase; AP: alkaline phosphatase; AST: aspartic transaminase; DILD: drug-induced liver disease; DM: diabetes mellitus; HE: hepatic encephalopathy; HFM: hepatic functional mass; SAMe: S-Adenosyl methionine; UDCA: ursodeoxycholic acid. Iryna K, Helen M, Elena S. Drug-induced Liver Disease in Patients with Diabetes Mellitus. Euroasian J Hepato-Gastroenterol 2015;5(2):83-86.

Chemical and Hormonal Effects on STAT5b-Dependent Sexual Dimorphism of the Liver Transcriptome

PubMed Central

Oshida, Keiyu; Waxman, David J.; Corton, J. Christopher

2016-01-01

The growth hormone (GH)-activated transcription factor signal transducer and activator of transcription 5b (STAT5b) is a key regulator of sexually dimorphic gene expression in the liver. Suppression of hepatic STAT5b signaling is associated with lipid metabolic dysfunction leading to steatosis and liver cancer. In the companion publication, a STAT5b biomarker gene set was identified and used in a rank-based test to predict both increases and decreases in liver STAT5b activation status/function with high (≥ 97%) accuracy. Here, this computational approach was used to identify chemicals and hormones that activate (masculinize) or suppress (feminize) STAT5b function in a large, annotated mouse liver and primary hepatocyte gene expression compendium. Exposure to dihydrotestosterone and thyroid hormone caused liver masculinization, whereas glucocorticoids, fibroblast growth factor 15, and angiotensin II caused liver feminization. In mouse models of diabetes and obesity, liver feminization was consistently observed and was at least partially reversed by leptin or resveratrol exposure. Chemical-induced feminization of male mouse liver gene expression profiles was a relatively frequent phenomenon: of 156 gene expression biosets from chemically-treated male mice, 29% showed feminization of liver STAT5b function, while <1% showed masculinization. Most (93%) of the biosets that exhibited feminization of male liver were also associated with activation of one or more xenobiotic-responsive receptors, most commonly constitutive activated receptor (CAR) or peroxisome proliferator-activated receptor alpha (PPARα). Feminization was consistently associated with increased expression of peroxisome proliferator-activated receptor gamma (Pparg) but not other lipogenic transcription factors linked to steatosis. GH-activated STAT5b signaling in mouse liver is thus commonly altered by diverse chemicals, and provides a linkage between chemical exposure and dysregulated gene expression

Nrf2 activation prevents cadmium-induced acute liver injury

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Kai C.; Liu, Jie J.; Klaassen, Curtis D., E-mail: cklaasse@kumc.edu

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-nullmore » 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

Indirubin Treatment of Lipopolysaccharide-Induced Mastitis in a Mouse Model and Activity in Mouse Mammary Epithelial Cells.

PubMed

Lai, Jin-Lun; Liu, Yu-Hui; Peng, Yong-Chong; Ge, Pan; He, Chen-Fei; Liu, Chang; Chen, Ying-Yu; Guo, Ai-Zhen; Hu, Chang-Min

2017-01-01

Indirubin is a Chinese medicine extracted from indigo and known to be effective for treating chronic myelogenous leukemia, neoplasia, and inflammatory disease. This study evaluated the in vivo anti-inflammatory activity of indirubin in a lipopolysaccharide- (LPS-) induced mouse mastitis model. The indirubin mechanism and targets were evaluated in vitro in mouse mammary epithelial cells. In the mouse model, indirubin significantly attenuated the severity of inflammatory lesions, edema, inflammatory hyperemia, milk stasis and local tissue necrosis, and neutrophil infiltration. Indirubin significantly decreased myeloperoxidase activity and downregulated the production of tumor necrosis factor- α , interleukin-1 β (IL-1 β ), and IL-6 caused by LPS. In vitro, indirubin inhibited LPS-stimulated expression of proinflammatory cytokines in a dose-dependent manner. It also downregulated LPS-induced toll-like receptor 4 (TLR4) expression and inhibited phosphorylation of LPS-induced nuclear transcription factor-kappa B (NF- κ B) P65 protein and inhibitor of kappa B. In addition to its effect on the NF- κ B signaling pathway, indirubin suppressed the mitogen-activated protein kinase (MAPK) signaling by inhibiting phosphorylation of extracellular signal-regulated kinase (ERK), P38, and c-jun NH2-terminal kinase (JNK). Indirubin improved LPS-induced mouse mastitis by suppressing TLR4 and downstream NF- κ B and MAPK pathway inflammatory signals and might be a potential treatment of mastitis and other inflammatory diseases.

Hepatoprotective effects of setarud against carbon tetrachloride-induced liver injury in rats.

PubMed

Khorshid, Hamid Reza Khorram; Azonov, Jahan A; Novitsky, Yury A; Farzamfar, Bardia; Shahhosseiny, Mohammad Hassan

2008-01-01

To assess the hepatoprotective activity of a new herbal drug "setarud" in experimental liver fibrosis, 48 male Wistar rats were divided into four groups: controls, carbon tetrachloride (CCl4) group, and two treatment groups that received CCl4 and setarud at doses of 0.02 or 0.04 g/Kg/day for 30 days. Body weight gain, biochemical liver tests, bile flow rate and composition, and changes in liver morphology in the four groups were studied. CCl4 administration led to morphological and biochemical evidence of liver injury as compared to untreated controls. Setarud administration led to significant protection against CCl4-induced changes in body weight gain, liver morphology, bile flow and concentration. It was also associated with significantly lower serum liver enzyme levels (p<0.01), higher serum albumin level, and reduced increase in narcotic-induced sleeping time. Thus, setarud showed protective activity against CCl4-induced hepatotoxicity in rats. Further studies of its efficacy in liver disease are warranted.

Hexachlorobenzene induces cell proliferation, and aryl hydrocarbon receptor expression (AhR) in rat liver preneoplastic foci, and in the human hepatoma cell line HepG2. AhR is a mediator of ERK1/2 signaling, and cell cycle regulation in HCB-treated HepG2 cells.

PubMed

de Tomaso Portaz, Ana Clara; Caimi, Giselle Romero; Sánchez, Marcela; Chiappini, Florencia; Randi, Andrea S; Kleiman de Pisarev, Diana L; Alvarez, Laura

2015-10-02

Hexachlorobenzene (HCB) is a widespread environmental pollutant, and a liver tumor promoter in rodents. Depending on the particular cell lines studied, exposure to these compounds may lead to cell proliferation, terminal differentiation, or apoptosis. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is involved in drug and xenobiotic metabolism. AhR can also modulate a variety of cellular and physiological processes that can affect cell proliferation and cell fate determination. The mechanisms by which AhR ligands, both exogenous and endogenous, affect these processes involve multiple interactions between AhR and other signaling pathways. In the present study, we examined the effect of HCB on cell proliferation and AhR expression, using an initiation-promotion hepatocarcinogenesis protocol in rat liver and in the human-derived hepatoma cell line, HepG2. Female Wistar rats were initiated with a single dose of 100 mg/kg of diethylnitrosamine (DEN) at the start of the experiment. Two weeks later, daily dosing of 100 mg/kg HCB was maintained for 10 weeks. Partial hepatectomy was performed 3 weeks after initiation. The number and area of glutathione S-transferase-P (GST-P)-positive foci, in the rat liver were used as biomarkers of liver precancerous lesions. Immunohistochemical staining showed an increase in proliferating cell nuclear antigen (PCNA)-positive cells, along with enhanced AhR protein expression in hepatocytes within GST-P-positive foci of (DEN HCB) group, when compared to DEN. In a similar manner, Western blot analysis demonstrated that HCB induced PCNA and AhR protein expression in HepG2 cells. Flow cytometry assay indicated that the cells were accumulated at S and G2/M phases of the cell cycle. HCB increased cyclin D1 protein levels and ERK1/2 phosphorylation in a dose-dependent manner. Treatment of cells with a selective MEK1 inhibitor, prevented HCB-stimulatory effect on PCNA and cyclinD1, indicating that these effects

Peroxisome proliferator-activated receptor (PPAR)-binding protein (PBP) but not PPAR-interacting protein (PRIP) is required for nuclear translocation of constitutive androstane receptor in mouse liver.

PubMed

Guo, Dongsheng; Sarkar, Joy; Ahmed, Mohamed R; Viswakarma, Navin; Jia, Yuzhi; Yu, Songtao; Sambasiva Rao, M; Reddy, Janardan K

2006-08-25

The constitutive androstane receptor (CAR) regulates transcription of phenobarbital-inducible genes that encode xenobiotic-metabolizing enzymes in liver. CAR is localized to the hepatocyte cytoplasm but to be functional, it translocates into the nucleus in the presence of phenobarbital-like CAR ligands. We now demonstrate that adenovirally driven EGFP-CAR, as expected, translocates into the nucleus of normal wild-type hepatocytes following phenobarbital treatment under both in vivo and in vitro conditions. Using this approach we investigated the role of transcription coactivators PBP and PRIP in the translocation of EGFP-CAR into the nucleus of PBP and PRIP liver conditional null mouse hepatocytes. We show that coactivator PBP is essential for nuclear translocation of CAR but not PRIP. Adenoviral expression of both PBP and EGFP-CAR restored phenobarbital-mediated nuclear translocation of exogenously expressed CAR in PBP null livers in vivo and in PBP null primary hepatocytes in vitro. CAR translocation into the nucleus of PRIP null livers resulted in the induction of CAR target genes such as CYP2B10, necessary for the conversion of acetaminophen to its hepatotoxic intermediate metabolite, N-acetyl-p-benzoquinone imine. As a consequence, PRIP-deficiency in liver did not protect from acetaminophen-induced hepatic necrosis, unlike that exerted by PBP deficiency. These results establish that transcription coactivator PBP plays a pivotal role in nuclear localization of CAR, that it is likely that PBP either enhances nuclear import or nuclear retention of CAR in hepatocytes, and that PRIP is redundant for CAR function.

Mice with hepatocyte-specific FXR deficiency are resistant to spontaneous but susceptible to cholic acid-induced hepatocarcinogenesis

PubMed Central

Zhu, Yan; Li, Guodong; Williams, Jessica A.; Buckley, Kyle; Tawfik, Ossama; Luyendyk, James P.

2016-01-01

Farnesoid X receptor (FXR) belongs to the nuclear receptor superfamily with its endogenous ligands bile acids. Mice with whole body FXR deficiency develop liver tumors spontaneously, but the underlying mechanism is unclear. Moreover, it is unknown whether FXR deficiency in liver alone serves as a tumor initiator or promoter during liver carcinogenesis. This study aims to evaluate the effects of hepatocyte-specific FXR deficiency (FXRhep−/−) in liver tumor formation. The results showed that FXRhep−/− mice did not show spontaneous liver tumorigenesis with aging (up to 24 mo of age). Therefore FXRhep−/− mice were fed a bile acid (cholic acid)-containing diet alone or along with a liver tumor initiator, diethylnitrosamine (DEN). Thirty weeks later, no tumors were found in wild-type or FXRhep−/− mice without any treatment or with DEN only. However, with cholic acid, while only some wild-type mice developed tumors, all FXRhep−/− mice presented with severe liver injury and tumors. Interestingly, FXRhep−/− mouse livers increased basal expression of tumor suppressor p53 protein, apoptosis, and decreased basal cyclin D1 expression, which may prevent tumor development in FXRhep−/− mice. However, cholic acid feeding reversed these effects in FXRhep−/− mice, which is associated with an increased cyclin D1 and decreased cell cycle inhibitors. More in-depth analysis indicates that the increased in cell growth might result from disturbance of the MAPK and JAK/Stat3 signaling pathways. In conclusion, this study shows that hepatic FXR deficiency may only serve as a tumor initiator, and increased bile acids is required for tumor formation likely by promoting cell proliferation. PMID:26744468

Proteomic Analyses of Cysteine Redox in High-Fat-Fed and Fasted Mouse Livers: Implications for Liver Metabolic Homeostasis.

PubMed

Li, Yixing; Luo, Zupeng; Wu, Xilong; Zhu, Jun; Yu, Kai; Jin, Yi; Zhang, Zhiwang; Zhao, Shuhong; Zhou, Lei

2018-01-05

Intensive oxidative stress occurs during high-fat-diet-induced hepatic fat deposition, suggesting a critical role for redox signaling in liver metabolism. Intriguingly, evidence shows that fasting could also result in redox-profile changes largely through reduced oxidant or increased antioxidant levels. However, a comprehensive landscape of redox-modified hepatic substrates is lacking, thereby hindering our understanding of liver metabolic homeostasis. We employed a proteomic approach combining iodoacetyl tandem mass tag and nanoliquid chromatography tandem mass spectrometry to quantitatively probe the effects of high-fat feeding and fasting on in vivo redox-based cysteine modifications. Compared with control groups, ∼60% of cysteine residues exhibited downregulated oxidation ratios by fasting, whereas ∼94% of these ratios were upregulated by high-fat feeding. Importantly, in fasted livers, proteins exhibiting diminished cysteine oxidation were annotated in pathways associated with fatty acid metabolism, carbohydrate metabolism, insulin, peroxisome proliferator-activated receptors, and oxidative respiratory chain signaling, suggesting that fasting-induced redox changes targeted major metabolic pathways and consequently resulted in hepatic lipid accumulation.

Thymoquinone Inhibits Tumor Growth and Induces Apoptosis in a Breast Cancer Xenograft Mouse Model: The Role of p38 MAPK and ROS

PubMed Central

Woo, Chern Chiuh; Hsu, Annie; Kumar, Alan Prem; Sethi, Gautam; Tan, Kwong Huat Benny

2013-01-01

Due to narrow therapeutic window of cancer therapeutic agents and the development of resistance against these agents, there is a need to discover novel agents to treat breast cancer. The antitumor activities of thymoquinone (TQ), a compound isolated from Nigella sativa oil, were investigated in breast carcinoma in vitro and in vivo. Cell responses after TQ treatment were assessed by using different assays including MTT assay, annexin V-propidium iodide staining, Mitosox staining and Western blot. The antitumor effect was studied by breast tumor xenograft mouse model, and the tumor tissues were examined by histology and immunohistochemistry. The level of anti-oxidant enzymes/molecules in mouse liver tissues was measured by commercial kits. Here, we show that TQ induced p38 phosphorylation and ROS production in breast cancer cells. These inductions were found to be responsible for TQ’s anti-proliferative and pro-apoptotic effects. Moreover, TQ-induced ROS production regulated p38 phosphorylation but not vice versa. TQ treatment was found to suppress the tumor growth and this effect was further enhanced by combination with doxorubicin. TQ also inhibited the protein expression of anti-apoptotic genes, such as XIAP, survivin, Bcl-xL and Bcl-2, in breast cancer cells and breast tumor xenograft. Reduced Ki67 and increased TUNEL staining were observed in TQ-treated tumors. TQ was also found to increase the level of catalase, superoxide dismutase and glutathione in mouse liver tissues. Overall, our results demonstrated that the anti-proliferative and pro-apoptotic effects of TQ in breast cancer are mediated through p38 phosphorylation via ROS generation. PMID:24098377

ω-3 PUFAs ameliorate liver fibrosis and inhibit hepatic stellate cells proliferation and activation by promoting YAP/TAZ degradation.