Studies performed in experimental small animalswith hepatic-based metabolic disorders but nostructural liver disease,including Gunn andanalbuminaemic rats and rabbits with inherited low-density lipoprotein receptor de...Studies performed in experimental small animalswith hepatic-based metabolic disorders but nostructural liver disease,including Gunn andanalbuminaemic rats and rabbits with inherited low-density lipoprotein receptor deficiency,have shownthat up to 95% of hepatocytes transplanted into thespleen or liver remain in these sites,withimprovement in metabolic function展开更多
AIM: To determine the therapeutic potential of sphingosine kinase 1(Sphk1) inhibition and its underlying mechanism in a well-characterized mouse model of D-galactosamine(D-Gal N)/lipopolysaccharide(LPS)-induced acute ...AIM: To determine the therapeutic potential of sphingosine kinase 1(Sphk1) inhibition and its underlying mechanism in a well-characterized mouse model of D-galactosamine(D-Gal N)/lipopolysaccharide(LPS)-induced acute liver failure(ALF).METHODS: Balb/c mice were randomly assigned to different groups,with ALF induced by intraperitoneal injection of D-Ga IN(600 mg/kg) and LPS(10 μg/kg). The Kaplan-Meier method was used for survival analysis. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) levels at different time points within one week were determined using a multi-parametric analyzer. Serum high-mobility group box 1(HMGB1),tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6,IL-10,and sphingosine-1-phosphate were detected by enzyme-linked immunosorbent assay. Hepatic morphological changes at 36 h after acute liver injury induction were assessed by hematoxylin and eosin staining. HMGB1 expression in hepatocytes and cytoplasmic translocation were detected by immunohistochemistry. Expression of Sphk1 in liver tissue and peripheral blood mononuclear cells(PBMCs) was analyzed by Western blot.RESULTS: The expression of Sphk1 in liver tissue and PBMCs was upregulated in Gal N/LPS-induced ALF. Upregulated Sphk1 expression in liver tissue was mainly caused by Kupffer cells,the resident macrophages of the liver. The survival rates of mice in the N,Ndimethylsphingosine(DMS,a specific inhibitor of Sph K1) treatment group were significantly higher than that of the control group(P < 0.001). DMS treatment significantly decreased the levels of serum ALT and AST at 6,12,and 24 h compared with that of the control group(P < 0.01 for all). Serum HMGB1 levels at 6,12,and 24 h,as well as serum TNF-α,IL-6,and IL-1β levels at 12 h,were significantly lower in the DMS treatment group than in the control group(P < 0.01 for all). Furthermore,hepatic inflammation,necrosis,and HMGB1 cytoplasm translocation in liver cells were significantly decreased in the DMS treatment group compared to the control group(43.72% ± 5.51% vs 3.57% ± 0.83%,χ2 = 12.81,P < 0.01).CONCLUSION: Inhibition of Sph K1 ameliorates ALF by reducing HMGB1 cytoplasmic translocation in liver cells,and so might be a potential therapeutic strategy for this disease.展开更多
AIM: To investigate the radiation response of various human tumor cells and normal liver cells.METHODS: Cell lines of human hepatoma cells (SMMC-7721),liver cells (L02), melanoma cells (A375) and cervical tumor (HeLa)...AIM: To investigate the radiation response of various human tumor cells and normal liver cells.METHODS: Cell lines of human hepatoma cells (SMMC-7721),liver cells (L02), melanoma cells (A375) and cervical tumor (HeLa) were irradiated with 60Co γ-rays. Cell survive was documented by a colony assay. Chromatid breaks were measured by counting the number of chromatid breaks and isochromatid breaks immediately after prematurely chromosome condensed by Calyculin-A.RESULTS: Linear quadratic survival curve was observed in all of four cell lines, and dose-dependent increase in radiation-induced chromatid and isochromatid breaks were observed in GB2B phase. Among these four cell lines,A375 was most sensitive to radiation, while, L02 had the lowest radiosensitivity. For normal liver cells, chromatid breaks were easy to be repaired, isochromatid breaks were difficult to be repaired.CONCLUSION: The results suggest that the γ-rays induced chromatid breaks can be possibly used as a good predictor of radiosensitivity, also, unrejoined isochromatid breaks probably tightly related with cell cancerization.展开更多
AIM: The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed...AIM: The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed a key role of growth factors for the induction of liver-specific genes in stem cell cultures. We investigated the potential of rat mesenchymal stem cells (MSC) from bone marrow to differentiate into hepatocytic cells in vitro. Furthermore,we assessed the influence of cocultured liver cells on induction of liver-specific gene expression.METHODS: Mesenchymal stem cells were marked with green fluorescent protein (GFP) by retroviral gene transduction. Clonal marked MSC were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with SCF, HGF,EGF, and FGF-4 alone, or in presence of freshly isolated rat liver cells. Cells in cocultures were harvested and GFP+ or GFP- cells were separated using fluorescence activated cell sorting. RT-PCR analysis for the stem cell marker Thy1 and the hepatocytic markers CK-18, albumin, CK-19,and AFP was performed in the different cell populations.RESULTS: Under the specified culture conditions, rat MSC cocultured with liver cells expressed albumin-, CK-18,CK-19, and AFP-RNA over 3 weeks, whereas MSC cultured alone did not show liver specific gene expression.CONCLUSION: The results indicate that (1) rat MSC from bone marrow can differentiate towards hepatocytic lineage in vitro, and (2) that the microenvironment plays a decisive role for the induction of hepatic differentiation of rMSC.展开更多
Liver innervation comprises sympathetic,parasympathetic and peptidergic nerve fibers,organized as either afferent or efferent nerves with different origins and roles.Their anatomy and physiology have been studied in t...Liver innervation comprises sympathetic,parasympathetic and peptidergic nerve fibers,organized as either afferent or efferent nerves with different origins and roles.Their anatomy and physiology have been studied in the past 30 years,with different results published over time.Hepatocytes are the main cell population of the liver,making up almost 80%of the total liver volume.The interaction between hepatocytes and nerve fibers is accomplished through a wealth of neurotransmitters and signaling pathways.In this short review,we have taken the task of condensing the most important data related to how the nervous system interacts with the liver and especially with the hepatocyte population,how it influences their metabolism and functions,and how different receptors and transmitters are involved in this complex process.展开更多
AIM:To demonstrate that CD14 + cells are an important source of the growth factor YKL40 in acute and chronic liver damage.METHODS:Rats were inoculated with one dose of CCl4 to induce acute damage.Liver biopsies were o...AIM:To demonstrate that CD14 + cells are an important source of the growth factor YKL40 in acute and chronic liver damage.METHODS:Rats were inoculated with one dose of CCl4 to induce acute damage.Liver biopsies were obtained at 0,6,12,24,48 and 72 h.For chronic damage,CCl4 was administered three days per week for 6 or 8 wk.Tissue samples were collected,and cellular populations were isolated by liver digestion and purified by cell sorting.YKL40 mRNA and protein expression were evaluated by realtime polymerase chain reaction and western blot.RESULTS:Acute liver damage induced a rapid increase of YKL40 mRNA beginning at 12 h.Expression peaked at 24 h,with a 26fold increase over basal levels.By 72 h however,YKL40 expression levels had nearly returned to control levels.On the other hand,chronic damage induced a sustained increase in YKL40 expression,with 7and 9fold higher levels at 6 and 8 wk,respectively.The pattern of YKL40 expression in different subpopulations showed that CD14+cells,which include Kupffer cells,are a source of YKL40 after acute damage at 72 h[0.09 relative expression units(REU)]as well as after chronic injury at 6 wk(0.11 REU).Hepatocytes,in turn,accounted for 0.06 and 0.01 REU after 72 h(acute)or 6 wk(chronic),respectively.The rest of the CD14cells(including T lymphocytes,B lymphocytes,natural killer and natural killer T cells) yielded 0.07 and 0.15 REU at 72 h and 6 wk,respectively.YKL40 protein expression in liver was detected at 72 h as well as 6 and 8 wk,with the highest expression relative to controls(11fold;P≤0.05)seen at 6 wk.Macrophages were stimulated by lipopolysaccharide.We demonstrate that under these conditions,these cells showed maximum expression of YKL40 at 12 h,with P<0.05 compared with controls.CONCLUSION:Hepatic CD14 + cells are an YKL40 mRNA and protein source in acute and chronic liver injury,with expression patterns similar to growth factors implicated in inflammationfibrogenesis.展开更多
Guava (Psidium guajava L.), a tropical fruit, belongs to Myrtaceae family. Leaves and fruits of guava have been reported to have an anti-diarrheal, hypoglycemic, lipid lowering, anti-bacterial in addition to antioxida...Guava (Psidium guajava L.), a tropical fruit, belongs to Myrtaceae family. Leaves and fruits of guava have been reported to have an anti-diarrheal, hypoglycemic, lipid lowering, anti-bacterial in addition to antioxidant activities. The aim of this study was to investigate several guava leaf extract cytotoxic effects on healthy clone 9 liver cells and its hepatoprotective effects on ethanol-induced heap-toxicity. It was discovered that when the clone 9 liver cells were treated with guava (Psidium guajava Linn.) extracts for 24 hours, there was no retardation of growth as well as when ethanol and acetone extracts at low concentrations 100 μg/mL and 50 μg/mL were administered however cytototoxic effects were detected at higher concentrations. Water and hot water extracts in concentrations lower than or equal to 500 μg/mL revealed no cytotoxic effects. Injury induction to healthy clone 9 liver cells using 5% alcohol concentration for 30 minutes revealed the hepatoprotective properties of guava (Psidium guajava Linn.) extracts. This was significant in concentrations of 100 μg/mL or lower for ethanol and all concentrations for hot water extracts. Hot water extracts showed higher hepatoprotective and lower cytotoxic properties than other extracts.展开更多
AIM: To investigate the influence of different quasispecies of hepatitis C virus (HCV) genotype 1b core protein on growth of Chang liver cells. METHODS: Three eukaryotic expression plasmids (pEGFP-N1/core) that contai...AIM: To investigate the influence of different quasispecies of hepatitis C virus (HCV) genotype 1b core protein on growth of Chang liver cells. METHODS: Three eukaryotic expression plasmids (pEGFP-N1/core) that contained different quasispecies truncated core proteins of HCV genotype 1b were constructed. These were derived from tumor (T) and non- tumor (NT) tissues of a patient infected with HCV and C191 (HCV-J6). The core protein expression plasmids were transiently transfected into Chang liver cells. At different times, the cell cycle and apoptosis was assayed by flow cytometry, and cell proliferation was assayed by methyl thiazolyl tetrazolium (MTT) assay. RESULTS: The proportion of S-phase Chang liver cells transfected with pEGFP-N1/core was significantly lower than that of cells transfected with blank plasmid at three different times after transfection (all P < 0.05). The proliferation ratio of cells transfected with pEGFP-N1/corewas significantly lower than that of cells transfected with blank plasmid. Among three different quasispecies, T, NT and C191 core expression cells, there was no significant difference in the proportion of S- and G0/G1-phase cells. The percentage of apoptotic cells was highest for T (T > NT > C191), and apoptosis was increased in cells transfected with pEGFP-N1/core as the transfection time increased (72 h > 48 h > 24 h). CONCLUSION: These results suggest that HCV genotype 1b core protein induces apoptosis, and inhibits cell- cycle progression and proliferation of Chang liver cells. Different quasispecies core proteins of HCV genotype 1b might have some differences in the pathogenesis of HCV persistent infection and hepatocellular carcinoma.展开更多
Human fetal liver cells were cultured in vitro for 12h and the supernatant(Fetal liver cell conditioned medium,FLCM)was collected.The effects of FLCM ongranulopoiesis were studied.The results show that when combined w...Human fetal liver cells were cultured in vitro for 12h and the supernatant(Fetal liver cell conditioned medium,FLCM)was collected.The effects of FLCM ongranulopoiesis were studied.The results show that when combined with colonystimulating factor(CSF),FLCM could significantly stimulate the proliferation of normalmyctoid progenitor cells(CFU-e),and increase ~3H-TdR incorporation into bone mar-row cells.The data suggest that FLCM contains a CSF synergistic activity.展开更多
BACKGROUND The morbidity and mortality of human immunodeficiency virus(HIV)-infection is often associated with liver disease,which progresses slowly into severe liver dysfunction.There are multiple insults which exace...BACKGROUND The morbidity and mortality of human immunodeficiency virus(HIV)-infection is often associated with liver disease,which progresses slowly into severe liver dysfunction.There are multiple insults which exacerbate HIV-related liver injury,including HIV-associated dysregulation of lipid metabolism and fat turnover,coinfections with hepatotropic viruses and alcohol abuse.As we reported before,exposure of hepatocytes to HIV and alcohol metabolites causes high oxidative stress,impairs proteasomal and lysosomal functions leading to accumulation of HIV in these cells,which end-ups with apoptotic cell death and finally promotes development of liver fibrosis.AIM To study whether obeticholic acid(OCA)prevents HIV/ethanol metabolisminduced hepatotoxicity and subsequent activation of hepatic stellate cells(HSC)by HIV+apoptotic hepatocyte engulfment.METHODS Huh7.5-CYP(RLW)cells were exposed to HIV and acetaldehyde-generating system(AGS)in the presence or absence of OCA.In the cells,we measured the expression of HIV-related markers:HIVgagRNA-by real-time polymerase chain reaction(PCR),p24-by western blot,HIV DNA-by semi-nested PCR,integrated HIV DNA-by ddPCR.Lysosomal and proteasomal activities were measured using fluorometrically-labeled substrates.For hepatocyte apoptosis,cleaved caspase 3 and cleaved PARP were visualized by western blot and cytokeratin 18-by M30 ELISA-in supernatants.Apoptotic bodies were generated from untreated and HIV-treated RLW cells exposed to UV light.Pro-fibrotic activation of HSC was characterized by Col1A1 and transforming growth factor-βmRNAs,while inflammasome activation-by NLRP3,caspase 1,interleukin(IL)-6,IL-1βmRNA levels.RESULTS In RLW cells,OCA treatment attenuated HIV-AGS-induced accumulation of HIVgagRNA,HIV DNA and p24.OCA suppressed reactive oxygen species production and restored chymotrypsin-like proteasome activity as well as cathepsin B lysosome activity.OCA also decreased HIV-AGS-triggered apoptosis in RLW cells.Exposure of HIV-containing apoptotic hepatocytes to HSC prevented activation of inflammasome and induced pro-fibrotic activation in these cells.CONCLUSION We conclude that by suppressing oxidative stress and restoring proteasomal and lysosomal functions impaired by HIV and ethanol metabolism,OCA decreases accumulation of HIV in hepatocytes,leading to down-regulation of apoptosis in these cells.In addition,OCA reverses pro-fibrotic and inflammasome-related activation of HSC triggered by engulfment of HIV-containing apoptotic hepatocytes,potentially contributing to suppression of liver fibrosis development.展开更多
Mequindox(MEQ),3-methyl-2-quinoxalinacetyl-1,4-dioxide,is widely used in Chinese veterinary medicine as an antimicrobial agent and feed additive.Its toxicity has been reported to be closely related to its metabolism.T...Mequindox(MEQ),3-methyl-2-quinoxalinacetyl-1,4-dioxide,is widely used in Chinese veterinary medicine as an antimicrobial agent and feed additive.Its toxicity has been reported to be closely related to its metabolism.To understand the pathways underlying MEQ's metabolism more clearly,we studied its metabolism in isolated rat liver cells by using liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole orbitrap(LC-LTQ-Orbitrap) mass spectrometry.The structures of MEQ metabolites and their product ions were readily and reliably characterized on the basis of accurate MS2 spectra and known structure of MEQ.Eleven metabolites were detected in isolated rat liver cells,two of which were detected for the first time in vitro.The major metabolic pathways reported previously for in vitro metabolism of MEQ in rat microsomes were confirmed in this study,including N → O group reduction,carbonyl reduction,and methyl monohydroxylation.In addition,we found that acetyl hydroxylation was an important pathway of MEQ metabolism.The results also demonstrate that cellular systems more closely simulate in vivo conditions than do other in vitro systems such as microsomes.Taken together,these data contribute to our understanding of the in vivo metabolism of MEQ.展开更多
AIM: To examine the efficacy of the radial flow bioreactor (RFB) as an extracorporeal bioartificial liver (BAL) and the reconstruction of liver organoids using embryonic pig liver cells. METHODS: We reconstructed the ...AIM: To examine the efficacy of the radial flow bioreactor (RFB) as an extracorporeal bioartificial liver (BAL) and the reconstruction of liver organoids using embryonic pig liver cells. METHODS: We reconstructed the liver organoids using embryonic porcine liver cells in the RFB. We also determined the gestational time window for the optimum growth of embryonic porcine liver cells. Five weeks of gestation was designated as embryonic day (E) 35 and 8 wk of gestation was designated as E56. These cells were cultured for one week before morphological and functional examinations. Moreover, the efficacy of pulsed administration of a high concentration hepatocyte growth factor (HGF) was examined. RESULTS: Both cell growth and function were excellent after harvesting on E35. The pulsed administration of a high concentration of HGF promoted the differentiation and maturation of these fetal hepatic cells. Microscopic examination of organoids in the RFB revealed palisading and showed that bile duct-like structures were well developed, indicating that the organoids were mini livers. Transmission electron microscopy revealed microvilli on the luminal surfaces of bile duct-like structures and junctional complexes, which form the basis of the cytoskeleton of epithelial tissues. Furthermore, strong expression of connexin (Cx) 32, which is the main protein of hepatocyte gap junctions, was observed. With respect to liver function, ammonia detoxification and urea synthesis were shown to be performed effectively. CONCLUSION: Our system can potentially be applied in the fields of BAL and transplantation medicine.展开更多
The rapid growth in global population continues to challenge the world’s ability to provide enough food. As one of the most crucial issues for human development, food production must increase to offset hunger and pov...The rapid growth in global population continues to challenge the world’s ability to provide enough food. As one of the most crucial issues for human development, food production must increase to offset hunger and poverty as well as social unrest. To augment the yield of crops a variety of pesticides like Endosulfan, Rogor, Aldrin, Chlorpyrifos, etc. are being used liberally by the farmers. In the present investigation, Endosulfan was administered orally (daily) by gavage method to female Swiss albino mice group for 4 weeks @ 3.0 mg/kg b.w. After that, they were left for 6 months and then sacrificed and liver tissues were fixed for light microscopy and Transmission Electron Microscopic study. The histopathological study of Endosulfan administered group liver showed hepatocytes with congestion in central vein with less dense cytoplasm, haemorrhaged bile duct, degenerated cytoplasm and central vein with vacuolations in sinusoidal spaces. Neoplastic changes in hepatocytes are the major finding of study. The ultrastuctural study revealed dilation in the nuclear pore complex and massive movement of cytoplasmic material from cytoplasm to the nucleus which is major finding which denotes neoplastic changes. Presence of abundant free lying polyribosomes in the cytoplasm, which denotes neoplastic changes in the cellis also one of theimportant finding observed. The present study thus deciphers that Endosulfan toxicity leads to onset of neoplasia thence carcinogenesis in liver cells in Swiss albino mice which is the novel finding in the field of toxicology.展开更多
The beneficial dffects of human fetal liver cells on the D-galactosamine-inducedfulminant hepatic failure were observed in rats and the mechanisms of the effects investi-gated.The survival rate of the rats intraperito...The beneficial dffects of human fetal liver cells on the D-galactosamine-inducedfulminant hepatic failure were observed in rats and the mechanisms of the effects investi-gated.The survival rate of the rats intraperitoneally injected with liver cell suspensionand cytosol was 47.37% and 42.11% respectively which was significantly higher than5.26% of the controls（P【0.05）.There was no statistical significance between the differ-ence of the survival rates due to two preparations.The administration of cytosol two hours before the intoduction of D-galactosamine re-sulted in a significant lowering of the plasma level of endotoxin and hepaticmalondialdehyde in rats and a marked increase of <sup>3</sup>H-thymindinc incorporation intohepatic DNA(DPM/OD<sub>260</sub>)as compared with the parameters of the controls.These re-sults suggest that there might be some biological active substance in human fetal liver cellswhich is responsible for thc effects to increase the survival rate.展开更多
Liver plays a central role in various physiological functions,including metabolism,biliary secretion,production of plasma proteins,regulation of hormones as well as detoxication.Because of its multidimensional functio...Liver plays a central role in various physiological functions,including metabolism,biliary secretion,production of plasma proteins,regulation of hormones as well as detoxication.Because of its multidimensional functions,liver diseases such as viral hepatitis,non-alcoholic fatty liver disease,non-alcoholic steato-hepatitis,fibrosis and liver cancer may lead to serious consequences.展开更多
Alcohol ingestion causes alteration in several cellular mechanisms, and leads to inflammation, apoptosis, immunological response defects, and fibrosis. These phenomena are associated with significant changes in the ep...Alcohol ingestion causes alteration in several cellular mechanisms, and leads to inflammation, apoptosis, immunological response defects, and fibrosis. These phenomena are associated with significant changes in the epigenetic mechanisms, and subsequently, to liver cell memory. The ubiquitin-proteasome pathway is one of the vital pathways in the cell that becomes dysfunctionial as a result of chronic ethanol consumption. Inhibition of the proteasome activity in the nucleus causes changes in the turnover of transcriptional factors, histone modifying enzymes, and therefore, affects epigenetic mechanisms. Alcohol consumption has been associated with an increase in histone acetylation and a decrease in histone methylation, which leads to gene expression changes. DNA and histone modifications that result from ethanol-induced proteasome inhibition are key players in regulating gene expression, especially genes involved in the cell cycle, immunological responses, and metabolism of ethanol. The present review highlights the consequences of ethanol-induced proteasome inhibition in the nucleus of liver cells that are chronically exposed to ethanol.展开更多
AIM:To investigate the effects of intravenous administration of the antioxidant glutathione (GSH) on reperfusion injury following liver transplantation.METHODS:Livers of male Lewis rats were transplanted after 24 h of...AIM:To investigate the effects of intravenous administration of the antioxidant glutathione (GSH) on reperfusion injury following liver transplantation.METHODS:Livers of male Lewis rats were transplanted after 24 h of hypothermic preservation in University of Wisconsin solution in a syngeneic setting. During a 2-h reperfusion period either saline (controls,n=8) or GSH (50 or 100μmol/(h·kg),n=5 each) was continuously administered via the jugular vein.RESULTS:Two hours after starting reperfusion plasma ALT increased to 1 457±281U/L (mean±SE) in controls but to only 908_+187 U/L (P<0.05) in animals treated with 100μmol GSH/(h·kg).No protection was conveyed by 50μmol GSH/(h·kg).Cytoprotection was confirmed by morphological findings on electron microscopy:GSH treatment prevented detachment of sinusoidal endothelial cells (SECs) as well as loss of microvilli and mitochondrial swelling of hepatocytes. Accordingly, postischemic bile flow increased 2-fold. Intravital fluorescence microscopy revealed a nearly complete restoration of sinusoidal blood flow and a significant reduction of leukocyte adherence to sinusoids and postsinusoidal venules. Following infusion of 50μmol and 100 μmol GSH/(h·kg),plasma GSH increased to 65±7mol/L and 97±18μmol/L,but to only 20±3mol/L in untreated recipients.Furthermore, plasma glutathione disulfide (GSSG) increased to 7.5±1.0mol/L in animals treated with 100μmol/(h·kg) GSH but infusion of 50μmol GSH/(h·kg) did not raise levels of untreated controls (1.8±0.5mol/L vs 2.2±0.2mol/L).CONCLUSION:Plasma GSH levels above a critical level may act as a “sink” for ROS produced in the hepatic vasculature during reperfusion of liver grafts.Therefore, GSH can be considered a candidate antioxidant for the prevention of reperfusion injury after liver transplantation, in particular since it has a low toxicity in humans.展开更多
In order to investigate the effect of hepatitis B virus (HBV) and aflatoxin B 1 (AFB 1) on hepatocarcinogenesis, the human embryonic liver cells infected with HBV were transplanted to nude mice by subcutaneous route a...In order to investigate the effect of hepatitis B virus (HBV) and aflatoxin B 1 (AFB 1) on hepatocarcinogenesis, the human embryonic liver cells infected with HBV were transplanted to nude mice by subcutaneous route and the transplanted mice were divided into 4 groups for study, in which the group A of mice was injected with HBV-infected human embryonic liver cells and followed by injections of AFB 1 once a week (HBV+AFB 1); the group B was treated with HBV as group A, but no AFB 1 was given (HBV +); the group C was injected with normal human embryonic liver cells and AFB 1 was used as group (AFB 1 +) and the group D or control group was injected with normal embryonic liver cells without addition of AFB 1. The experimental results showed that the incidences of tumor formation in different groups were 27.3% (6/22) in group A; 0% (0/13) in group B; 13.3% (2/15) in group C and 0% (0/14) in group D respectively. All the tumors formed were proved to be human hepatocellular carcinoma (HCC) by pathological examinations and the tumor tissues were anthrogenetic as demonstrated by EMA monoclonal antibody. The HBV-X and HBV-S genes could be detected in the tumor tissues by means of slot hybridization and PCR amplification, indicating that the HBV-DNA genes had integrated into DNA of host cells. Thus, we have successfully induced the human HCC through HBV infection and introduction of AFB 1 with a synergistic effect between HBV and AFB 1 in hepatocarcinogenesis.展开更多
文摘Studies performed in experimental small animalswith hepatic-based metabolic disorders but nostructural liver disease,including Gunn andanalbuminaemic rats and rabbits with inherited low-density lipoprotein receptor deficiency,have shownthat up to 95% of hepatocytes transplanted into thespleen or liver remain in these sites,withimprovement in metabolic function
基金Supported by the National Natural Science Foundation of ChinaNo.81160065
文摘AIM: To determine the therapeutic potential of sphingosine kinase 1(Sphk1) inhibition and its underlying mechanism in a well-characterized mouse model of D-galactosamine(D-Gal N)/lipopolysaccharide(LPS)-induced acute liver failure(ALF).METHODS: Balb/c mice were randomly assigned to different groups,with ALF induced by intraperitoneal injection of D-Ga IN(600 mg/kg) and LPS(10 μg/kg). The Kaplan-Meier method was used for survival analysis. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) levels at different time points within one week were determined using a multi-parametric analyzer. Serum high-mobility group box 1(HMGB1),tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6,IL-10,and sphingosine-1-phosphate were detected by enzyme-linked immunosorbent assay. Hepatic morphological changes at 36 h after acute liver injury induction were assessed by hematoxylin and eosin staining. HMGB1 expression in hepatocytes and cytoplasmic translocation were detected by immunohistochemistry. Expression of Sphk1 in liver tissue and peripheral blood mononuclear cells(PBMCs) was analyzed by Western blot.RESULTS: The expression of Sphk1 in liver tissue and PBMCs was upregulated in Gal N/LPS-induced ALF. Upregulated Sphk1 expression in liver tissue was mainly caused by Kupffer cells,the resident macrophages of the liver. The survival rates of mice in the N,Ndimethylsphingosine(DMS,a specific inhibitor of Sph K1) treatment group were significantly higher than that of the control group(P < 0.001). DMS treatment significantly decreased the levels of serum ALT and AST at 6,12,and 24 h compared with that of the control group(P < 0.01 for all). Serum HMGB1 levels at 6,12,and 24 h,as well as serum TNF-α,IL-6,and IL-1β levels at 12 h,were significantly lower in the DMS treatment group than in the control group(P < 0.01 for all). Furthermore,hepatic inflammation,necrosis,and HMGB1 cytoplasm translocation in liver cells were significantly decreased in the DMS treatment group compared to the control group(43.72% ± 5.51% vs 3.57% ± 0.83%,χ2 = 12.81,P < 0.01).CONCLUSION: Inhibition of Sph K1 ameliorates ALF by reducing HMGB1 cytoplasmic translocation in liver cells,and so might be a potential therapeutic strategy for this disease.
基金Supported by the National Natural Science Foundation of China, No. 10335050Ministry of Science and Technology of the People's Republic of China, No. 2003CCB00200
文摘AIM: To investigate the radiation response of various human tumor cells and normal liver cells.METHODS: Cell lines of human hepatoma cells (SMMC-7721),liver cells (L02), melanoma cells (A375) and cervical tumor (HeLa) were irradiated with 60Co γ-rays. Cell survive was documented by a colony assay. Chromatid breaks were measured by counting the number of chromatid breaks and isochromatid breaks immediately after prematurely chromosome condensed by Calyculin-A.RESULTS: Linear quadratic survival curve was observed in all of four cell lines, and dose-dependent increase in radiation-induced chromatid and isochromatid breaks were observed in GB2B phase. Among these four cell lines,A375 was most sensitive to radiation, while, L02 had the lowest radiosensitivity. For normal liver cells, chromatid breaks were easy to be repaired, isochromatid breaks were difficult to be repaired.CONCLUSION: The results suggest that the γ-rays induced chromatid breaks can be possibly used as a good predictor of radiosensitivity, also, unrejoined isochromatid breaks probably tightly related with cell cancerization.
基金Supported by the "Rudoff Bartling Foundation" and "Foerdergemeinschaft Kinder-Krebs-Zentrum Hamburg e.V."
文摘AIM: The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed a key role of growth factors for the induction of liver-specific genes in stem cell cultures. We investigated the potential of rat mesenchymal stem cells (MSC) from bone marrow to differentiate into hepatocytic cells in vitro. Furthermore,we assessed the influence of cocultured liver cells on induction of liver-specific gene expression.METHODS: Mesenchymal stem cells were marked with green fluorescent protein (GFP) by retroviral gene transduction. Clonal marked MSC were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with SCF, HGF,EGF, and FGF-4 alone, or in presence of freshly isolated rat liver cells. Cells in cocultures were harvested and GFP+ or GFP- cells were separated using fluorescence activated cell sorting. RT-PCR analysis for the stem cell marker Thy1 and the hepatocytic markers CK-18, albumin, CK-19,and AFP was performed in the different cell populations.RESULTS: Under the specified culture conditions, rat MSC cocultured with liver cells expressed albumin-, CK-18,CK-19, and AFP-RNA over 3 weeks, whereas MSC cultured alone did not show liver specific gene expression.CONCLUSION: The results indicate that (1) rat MSC from bone marrow can differentiate towards hepatocytic lineage in vitro, and (2) that the microenvironment plays a decisive role for the induction of hepatic differentiation of rMSC.
文摘Liver innervation comprises sympathetic,parasympathetic and peptidergic nerve fibers,organized as either afferent or efferent nerves with different origins and roles.Their anatomy and physiology have been studied in the past 30 years,with different results published over time.Hepatocytes are the main cell population of the liver,making up almost 80%of the total liver volume.The interaction between hepatocytes and nerve fibers is accomplished through a wealth of neurotransmitters and signaling pathways.In this short review,we have taken the task of condensing the most important data related to how the nervous system interacts with the liver and especially with the hepatocyte population,how it influences their metabolism and functions,and how different receptors and transmitters are involved in this complex process.
基金Supported by Complementary support CONACyT 90361
文摘AIM:To demonstrate that CD14 + cells are an important source of the growth factor YKL40 in acute and chronic liver damage.METHODS:Rats were inoculated with one dose of CCl4 to induce acute damage.Liver biopsies were obtained at 0,6,12,24,48 and 72 h.For chronic damage,CCl4 was administered three days per week for 6 or 8 wk.Tissue samples were collected,and cellular populations were isolated by liver digestion and purified by cell sorting.YKL40 mRNA and protein expression were evaluated by realtime polymerase chain reaction and western blot.RESULTS:Acute liver damage induced a rapid increase of YKL40 mRNA beginning at 12 h.Expression peaked at 24 h,with a 26fold increase over basal levels.By 72 h however,YKL40 expression levels had nearly returned to control levels.On the other hand,chronic damage induced a sustained increase in YKL40 expression,with 7and 9fold higher levels at 6 and 8 wk,respectively.The pattern of YKL40 expression in different subpopulations showed that CD14+cells,which include Kupffer cells,are a source of YKL40 after acute damage at 72 h[0.09 relative expression units(REU)]as well as after chronic injury at 6 wk(0.11 REU).Hepatocytes,in turn,accounted for 0.06 and 0.01 REU after 72 h(acute)or 6 wk(chronic),respectively.The rest of the CD14cells(including T lymphocytes,B lymphocytes,natural killer and natural killer T cells) yielded 0.07 and 0.15 REU at 72 h and 6 wk,respectively.YKL40 protein expression in liver was detected at 72 h as well as 6 and 8 wk,with the highest expression relative to controls(11fold;P≤0.05)seen at 6 wk.Macrophages were stimulated by lipopolysaccharide.We demonstrate that under these conditions,these cells showed maximum expression of YKL40 at 12 h,with P<0.05 compared with controls.CONCLUSION:Hepatic CD14 + cells are an YKL40 mRNA and protein source in acute and chronic liver injury,with expression patterns similar to growth factors implicated in inflammationfibrogenesis.
文摘Guava (Psidium guajava L.), a tropical fruit, belongs to Myrtaceae family. Leaves and fruits of guava have been reported to have an anti-diarrheal, hypoglycemic, lipid lowering, anti-bacterial in addition to antioxidant activities. The aim of this study was to investigate several guava leaf extract cytotoxic effects on healthy clone 9 liver cells and its hepatoprotective effects on ethanol-induced heap-toxicity. It was discovered that when the clone 9 liver cells were treated with guava (Psidium guajava Linn.) extracts for 24 hours, there was no retardation of growth as well as when ethanol and acetone extracts at low concentrations 100 μg/mL and 50 μg/mL were administered however cytototoxic effects were detected at higher concentrations. Water and hot water extracts in concentrations lower than or equal to 500 μg/mL revealed no cytotoxic effects. Injury induction to healthy clone 9 liver cells using 5% alcohol concentration for 30 minutes revealed the hepatoprotective properties of guava (Psidium guajava Linn.) extracts. This was significant in concentrations of 100 μg/mL or lower for ethanol and all concentrations for hot water extracts. Hot water extracts showed higher hepatoprotective and lower cytotoxic properties than other extracts.
基金The Nature Science Foundation of Jiangsu, No. BK2007031The College Education Nature Science Foundation of Jiangsu, No. 05KJB320137
文摘AIM: To investigate the influence of different quasispecies of hepatitis C virus (HCV) genotype 1b core protein on growth of Chang liver cells. METHODS: Three eukaryotic expression plasmids (pEGFP-N1/core) that contained different quasispecies truncated core proteins of HCV genotype 1b were constructed. These were derived from tumor (T) and non- tumor (NT) tissues of a patient infected with HCV and C191 (HCV-J6). The core protein expression plasmids were transiently transfected into Chang liver cells. At different times, the cell cycle and apoptosis was assayed by flow cytometry, and cell proliferation was assayed by methyl thiazolyl tetrazolium (MTT) assay. RESULTS: The proportion of S-phase Chang liver cells transfected with pEGFP-N1/core was significantly lower than that of cells transfected with blank plasmid at three different times after transfection (all P < 0.05). The proliferation ratio of cells transfected with pEGFP-N1/corewas significantly lower than that of cells transfected with blank plasmid. Among three different quasispecies, T, NT and C191 core expression cells, there was no significant difference in the proportion of S- and G0/G1-phase cells. The percentage of apoptotic cells was highest for T (T > NT > C191), and apoptosis was increased in cells transfected with pEGFP-N1/core as the transfection time increased (72 h > 48 h > 24 h). CONCLUSION: These results suggest that HCV genotype 1b core protein induces apoptosis, and inhibits cell- cycle progression and proliferation of Chang liver cells. Different quasispecies core proteins of HCV genotype 1b might have some differences in the pathogenesis of HCV persistent infection and hepatocellular carcinoma.
文摘Human fetal liver cells were cultured in vitro for 12h and the supernatant(Fetal liver cell conditioned medium,FLCM)was collected.The effects of FLCM ongranulopoiesis were studied.The results show that when combined with colonystimulating factor(CSF),FLCM could significantly stimulate the proliferation of normalmyctoid progenitor cells(CFU-e),and increase ~3H-TdR incorporation into bone mar-row cells.The data suggest that FLCM contains a CSF synergistic activity.
文摘BACKGROUND The morbidity and mortality of human immunodeficiency virus(HIV)-infection is often associated with liver disease,which progresses slowly into severe liver dysfunction.There are multiple insults which exacerbate HIV-related liver injury,including HIV-associated dysregulation of lipid metabolism and fat turnover,coinfections with hepatotropic viruses and alcohol abuse.As we reported before,exposure of hepatocytes to HIV and alcohol metabolites causes high oxidative stress,impairs proteasomal and lysosomal functions leading to accumulation of HIV in these cells,which end-ups with apoptotic cell death and finally promotes development of liver fibrosis.AIM To study whether obeticholic acid(OCA)prevents HIV/ethanol metabolisminduced hepatotoxicity and subsequent activation of hepatic stellate cells(HSC)by HIV+apoptotic hepatocyte engulfment.METHODS Huh7.5-CYP(RLW)cells were exposed to HIV and acetaldehyde-generating system(AGS)in the presence or absence of OCA.In the cells,we measured the expression of HIV-related markers:HIVgagRNA-by real-time polymerase chain reaction(PCR),p24-by western blot,HIV DNA-by semi-nested PCR,integrated HIV DNA-by ddPCR.Lysosomal and proteasomal activities were measured using fluorometrically-labeled substrates.For hepatocyte apoptosis,cleaved caspase 3 and cleaved PARP were visualized by western blot and cytokeratin 18-by M30 ELISA-in supernatants.Apoptotic bodies were generated from untreated and HIV-treated RLW cells exposed to UV light.Pro-fibrotic activation of HSC was characterized by Col1A1 and transforming growth factor-βmRNAs,while inflammasome activation-by NLRP3,caspase 1,interleukin(IL)-6,IL-1βmRNA levels.RESULTS In RLW cells,OCA treatment attenuated HIV-AGS-induced accumulation of HIVgagRNA,HIV DNA and p24.OCA suppressed reactive oxygen species production and restored chymotrypsin-like proteasome activity as well as cathepsin B lysosome activity.OCA also decreased HIV-AGS-triggered apoptosis in RLW cells.Exposure of HIV-containing apoptotic hepatocytes to HSC prevented activation of inflammasome and induced pro-fibrotic activation in these cells.CONCLUSION We conclude that by suppressing oxidative stress and restoring proteasomal and lysosomal functions impaired by HIV and ethanol metabolism,OCA decreases accumulation of HIV in hepatocytes,leading to down-regulation of apoptosis in these cells.In addition,OCA reverses pro-fibrotic and inflammasome-related activation of HSC triggered by engulfment of HIV-containing apoptotic hepatocytes,potentially contributing to suppression of liver fibrosis development.
基金financially supported by the National Basic Research Program of China(2009CB118800)
文摘Mequindox(MEQ),3-methyl-2-quinoxalinacetyl-1,4-dioxide,is widely used in Chinese veterinary medicine as an antimicrobial agent and feed additive.Its toxicity has been reported to be closely related to its metabolism.To understand the pathways underlying MEQ's metabolism more clearly,we studied its metabolism in isolated rat liver cells by using liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole orbitrap(LC-LTQ-Orbitrap) mass spectrometry.The structures of MEQ metabolites and their product ions were readily and reliably characterized on the basis of accurate MS2 spectra and known structure of MEQ.Eleven metabolites were detected in isolated rat liver cells,two of which were detected for the first time in vitro.The major metabolic pathways reported previously for in vitro metabolism of MEQ in rat microsomes were confirmed in this study,including N → O group reduction,carbonyl reduction,and methyl monohydroxylation.In addition,we found that acetyl hydroxylation was an important pathway of MEQ metabolism.The results also demonstrate that cellular systems more closely simulate in vivo conditions than do other in vitro systems such as microsomes.Taken together,these data contribute to our understanding of the in vivo metabolism of MEQ.
基金Supported by Grants-In-Aid from the University Start-Up Creation Support Systemthe Promotion and Mutual Aid Corporation for Private School of Japanthe Japan Health Sciences Foundation, Research on Health Science on Drug Innovation, No. KH 71068
文摘AIM: To examine the efficacy of the radial flow bioreactor (RFB) as an extracorporeal bioartificial liver (BAL) and the reconstruction of liver organoids using embryonic pig liver cells. METHODS: We reconstructed the liver organoids using embryonic porcine liver cells in the RFB. We also determined the gestational time window for the optimum growth of embryonic porcine liver cells. Five weeks of gestation was designated as embryonic day (E) 35 and 8 wk of gestation was designated as E56. These cells were cultured for one week before morphological and functional examinations. Moreover, the efficacy of pulsed administration of a high concentration hepatocyte growth factor (HGF) was examined. RESULTS: Both cell growth and function were excellent after harvesting on E35. The pulsed administration of a high concentration of HGF promoted the differentiation and maturation of these fetal hepatic cells. Microscopic examination of organoids in the RFB revealed palisading and showed that bile duct-like structures were well developed, indicating that the organoids were mini livers. Transmission electron microscopy revealed microvilli on the luminal surfaces of bile duct-like structures and junctional complexes, which form the basis of the cytoskeleton of epithelial tissues. Furthermore, strong expression of connexin (Cx) 32, which is the main protein of hepatocyte gap junctions, was observed. With respect to liver function, ammonia detoxification and urea synthesis were shown to be performed effectively. CONCLUSION: Our system can potentially be applied in the fields of BAL and transplantation medicine.
文摘The rapid growth in global population continues to challenge the world’s ability to provide enough food. As one of the most crucial issues for human development, food production must increase to offset hunger and poverty as well as social unrest. To augment the yield of crops a variety of pesticides like Endosulfan, Rogor, Aldrin, Chlorpyrifos, etc. are being used liberally by the farmers. In the present investigation, Endosulfan was administered orally (daily) by gavage method to female Swiss albino mice group for 4 weeks @ 3.0 mg/kg b.w. After that, they were left for 6 months and then sacrificed and liver tissues were fixed for light microscopy and Transmission Electron Microscopic study. The histopathological study of Endosulfan administered group liver showed hepatocytes with congestion in central vein with less dense cytoplasm, haemorrhaged bile duct, degenerated cytoplasm and central vein with vacuolations in sinusoidal spaces. Neoplastic changes in hepatocytes are the major finding of study. The ultrastuctural study revealed dilation in the nuclear pore complex and massive movement of cytoplasmic material from cytoplasm to the nucleus which is major finding which denotes neoplastic changes. Presence of abundant free lying polyribosomes in the cytoplasm, which denotes neoplastic changes in the cellis also one of theimportant finding observed. The present study thus deciphers that Endosulfan toxicity leads to onset of neoplasia thence carcinogenesis in liver cells in Swiss albino mice which is the novel finding in the field of toxicology.
文摘The beneficial dffects of human fetal liver cells on the D-galactosamine-inducedfulminant hepatic failure were observed in rats and the mechanisms of the effects investi-gated.The survival rate of the rats intraperitoneally injected with liver cell suspensionand cytosol was 47.37% and 42.11% respectively which was significantly higher than5.26% of the controls（P【0.05）.There was no statistical significance between the differ-ence of the survival rates due to two preparations.The administration of cytosol two hours before the intoduction of D-galactosamine re-sulted in a significant lowering of the plasma level of endotoxin and hepaticmalondialdehyde in rats and a marked increase of <sup>3</sup>H-thymindinc incorporation intohepatic DNA(DPM/OD<sub>260</sub>)as compared with the parameters of the controls.These re-sults suggest that there might be some biological active substance in human fetal liver cellswhich is responsible for thc effects to increase the survival rate.
文摘Liver plays a central role in various physiological functions,including metabolism,biliary secretion,production of plasma proteins,regulation of hormones as well as detoxication.Because of its multidimensional functions,liver diseases such as viral hepatitis,non-alcoholic fatty liver disease,non-alcoholic steato-hepatitis,fibrosis and liver cancer may lead to serious consequences.
文摘Alcohol ingestion causes alteration in several cellular mechanisms, and leads to inflammation, apoptosis, immunological response defects, and fibrosis. These phenomena are associated with significant changes in the epigenetic mechanisms, and subsequently, to liver cell memory. The ubiquitin-proteasome pathway is one of the vital pathways in the cell that becomes dysfunctionial as a result of chronic ethanol consumption. Inhibition of the proteasome activity in the nucleus causes changes in the turnover of transcriptional factors, histone modifying enzymes, and therefore, affects epigenetic mechanisms. Alcohol consumption has been associated with an increase in histone acetylation and a decrease in histone methylation, which leads to gene expression changes. DNA and histone modifications that result from ethanol-induced proteasome inhibition are key players in regulating gene expression, especially genes involved in the cell cycle, immunological responses, and metabolism of ethanol. The present review highlights the consequences of ethanol-induced proteasome inhibition in the nucleus of liver cells that are chronically exposed to ethanol.
基金Supported in part by a grant from the Friedrich-Baur Stiftung,the Muenchener Medizinische Wochenschrift (MMW)the Deutsche Forschungsgemeinschaft (DFG Scha 857/1-1DFG FOR 440-717)
文摘AIM:To investigate the effects of intravenous administration of the antioxidant glutathione (GSH) on reperfusion injury following liver transplantation.METHODS:Livers of male Lewis rats were transplanted after 24 h of hypothermic preservation in University of Wisconsin solution in a syngeneic setting. During a 2-h reperfusion period either saline (controls,n=8) or GSH (50 or 100μmol/(h·kg),n=5 each) was continuously administered via the jugular vein.RESULTS:Two hours after starting reperfusion plasma ALT increased to 1 457±281U/L (mean±SE) in controls but to only 908_+187 U/L (P<0.05) in animals treated with 100μmol GSH/(h·kg).No protection was conveyed by 50μmol GSH/(h·kg).Cytoprotection was confirmed by morphological findings on electron microscopy:GSH treatment prevented detachment of sinusoidal endothelial cells (SECs) as well as loss of microvilli and mitochondrial swelling of hepatocytes. Accordingly, postischemic bile flow increased 2-fold. Intravital fluorescence microscopy revealed a nearly complete restoration of sinusoidal blood flow and a significant reduction of leukocyte adherence to sinusoids and postsinusoidal venules. Following infusion of 50μmol and 100 μmol GSH/(h·kg),plasma GSH increased to 65±7mol/L and 97±18μmol/L,but to only 20±3mol/L in untreated recipients.Furthermore, plasma glutathione disulfide (GSSG) increased to 7.5±1.0mol/L in animals treated with 100μmol/(h·kg) GSH but infusion of 50μmol GSH/(h·kg) did not raise levels of untreated controls (1.8±0.5mol/L vs 2.2±0.2mol/L).CONCLUSION:Plasma GSH levels above a critical level may act as a “sink” for ROS produced in the hepatic vasculature during reperfusion of liver grafts.Therefore, GSH can be considered a candidate antioxidant for the prevention of reperfusion injury after liver transplantation, in particular since it has a low toxicity in humans.
基金This research was supported in whole with key program from National Natural Science Foundation of China (No. 39830380)
文摘In order to investigate the effect of hepatitis B virus (HBV) and aflatoxin B 1 (AFB 1) on hepatocarcinogenesis, the human embryonic liver cells infected with HBV were transplanted to nude mice by subcutaneous route and the transplanted mice were divided into 4 groups for study, in which the group A of mice was injected with HBV-infected human embryonic liver cells and followed by injections of AFB 1 once a week (HBV+AFB 1); the group B was treated with HBV as group A, but no AFB 1 was given (HBV +); the group C was injected with normal human embryonic liver cells and AFB 1 was used as group (AFB 1 +) and the group D or control group was injected with normal embryonic liver cells without addition of AFB 1. The experimental results showed that the incidences of tumor formation in different groups were 27.3% (6/22) in group A; 0% (0/13) in group B; 13.3% (2/15) in group C and 0% (0/14) in group D respectively. All the tumors formed were proved to be human hepatocellular carcinoma (HCC) by pathological examinations and the tumor tissues were anthrogenetic as demonstrated by EMA monoclonal antibody. The HBV-X and HBV-S genes could be detected in the tumor tissues by means of slot hybridization and PCR amplification, indicating that the HBV-DNA genes had integrated into DNA of host cells. Thus, we have successfully induced the human HCC through HBV infection and introduction of AFB 1 with a synergistic effect between HBV and AFB 1 in hepatocarcinogenesis.
