AIM:To explore a method to establish an animal model of ischemic type intrahepatic biliary lesion in rabbits. METHODS:Forty Japanese white rabbits of clean grade were divided randomly into four groups(10 rabbits per g...AIM:To explore a method to establish an animal model of ischemic type intrahepatic biliary lesion in rabbits. METHODS:Forty Japanese white rabbits of clean grade were divided randomly into four groups(10 rabbits per group)including sham operation(SO) group,and artery-bile obstruction(ABO)-1 h group, ABO-2 h group and ABO-3 h group.All the rabbits in this study underwent the same initial surgical procedure in which the liver was prepared as for graft removal during liver transplantation.Subsequently in the SO group,no additional vascular intervention was performed,while in groups ABO-1 h,ABO-2 h and ABO-3 h,the animals underwent combined clamping of the hepatic artery and common bile duct with microvascular clips for 1,2 and 3 h,respectively.After the scheduled occlusion time,the clip was removed to recover blood supply.The animals were killed 4 wk after operation.The survival rate,liver function, cholangiography and histopathological manifestation of the rabbits in each group were observed. RESULTS:The survival rate was 100%in groups SO,ABO-1 h and ABO-2 h,while it was 60%in group ABO-3 h.At each observation time,the change degree of the indexes of liver function was proportional to the clamping time(ABO-3 h>ABO-2 h>ABO-1 h> SO,P<0.05).Cholangiographical and histopathologic manifestations both showed that intrahepatic biliary lesion aggravated proportionally with the increase of the clamping time. CONCLUSION:An animal model of ischemic type intrahepatic biliary lesion in rabbits is successfully established,which may provide a reliable technique for basic and clinical research into the etiology, development and prophylaxis of ischemic type intrahepatic biliary lesion after liver transplantation.展开更多
AIM: To evaluate the in vivo effect of glutamine on cobaltgenerated oxidative stress and (HO-1) induction in rat liver.METHODS: Fasted female Wistar rats received a single injection of cobalt chloride (375 μmol/kg bo...AIM: To evaluate the in vivo effect of glutamine on cobaltgenerated oxidative stress and (HO-1) induction in rat liver.METHODS: Fasted female Wistar rats received a single injection of cobalt chloride (375 μmol/kg body weight) and then were killed at different times. Lipid peroxidation and soluble and enzymatic antioxidant defense system (reduced glutathione (GSH), catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD)) were measured in liver homogenates. Ferritin and ferritin iron contents as well as heme oxygenase-1 (HO-1) activity and expression were also determined. The antioxidant properties of glutamine (Gin) were also evaluated. RESULTS: Cobalt chloride increased lipid peroxidation (50% over control values) 1 h after treatment. GSH reached a minimum at 3 h (40%) increasing thereafter. Twelve hours after CoCl2 injection, the antioxidant enzymes CAT, GSH-Px and SOD also diminished by about 30%. Heme oxygenase-1 induction was observed 6 h after treatment reaching a maximum value of 14-fold over the controls, 12 h after cobalt treatment. A 1.7-fold increase in ferritin and ferritin-bound iron 24 h after treatment were also obtained. Administration of glutamine (300 mg/kg body weight) by gavage 24 h before CoCl2 treatment entirely prevented the increase in thiobarbituric acid reactive substances (TBARS) content, the decrease in GSH levels, and partially reverted heme oxygenase-1 induction. CONCLUSION: These results suggested that a natural product such as glutamine prevents glutathione depletion and consequently heme oxygenase induction.展开更多
AIM: To elucidate the mechanisms of hepatocyte preconditioning by H2O2 to better understand the pathophysiology of ischemic preconditioning. METHODS: The in vitro effect of H2O2 pretreatment was investigated in rat is...AIM: To elucidate the mechanisms of hepatocyte preconditioning by H2O2 to better understand the pathophysiology of ischemic preconditioning. METHODS: The in vitro effect of H2O2 pretreatment was investigated in rat isolated hepatocytes subjected to anoxia/reoxygenation. Cell viability was assessed with propidium iodide fluorometry. In other experiments, rat livers were excised and subjected to warm ischemia/ reperfusion in an isolated perfused liver system to determine leakage of liver enzymes. Preconditioning was performed by H2O2 perfusion, or by stopping the perfusion for 10 min followed by 10 min of reperfusion. To inhibit Kupffer cell function or reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, gadolinium chloride was injected prior to liver excision, or diphenyleneiodonium, an inhibitor of NADPH oxidase, was added to the perfusate, respectively. Histological detection of oxygen radical formation in Kupffer cells was performed by perfusion with nitro blue tetrazolium. RESULTS: Anoxia/reoxygenation decreased hepatocyte viability compared to the controls. Pretreatment with H2O2 did not improve such hepatocyte injury. In liver perfusion experiments, however, H2O2 preconditioning reduced warm ischemia/reperfusion injury, which wasreversed by inhibition of Kupffer cell function or NADPH oxidase. Histological examination revealed that H2O2 preconditioning induced oxygen radical formation in Kupffer cells. NADPH oxidase inhibition also reversed hepatoprotection by ischemic preconditioning. CONCLUSION: H2O2 preconditioning protects hepato- cytes against warm ischemia/reperfusion injury via NADPH oxidase in Kupffer cells, and not directly. NADPH oxidase also mediates hepatoprotection by ischemic preconditioning.展开更多
AIM: To investigate the role of CXCL16 in the pathogenesis of immunological liver injury and to explore the possible mechanism ofT lymphocyte infiltration regulated by CXCL16. METHODS: Immunological liver injury in ...AIM: To investigate the role of CXCL16 in the pathogenesis of immunological liver injury and to explore the possible mechanism ofT lymphocyte infiltration regulated by CXCL16. METHODS: Immunological liver injury in murine model was induced by Bacille Calmette-Guerin and lipopolysaccharide. Expression pattern and distribution of CXCL16 were examined by real-time quantitative RT-PCR and immunohistochemical analysis. Anti-CXCL16 antibody was administrated in vivo to investigate its effect on T-cell recruitment and acute hepatic necrosis. The survival of murine model was also evaluated. RESULTS, The murine immunological liver injury model was successfully established, CXCL16 expression increased and predominantly distributed in periportal areas and vascular endothelia in injured liver tissues. Administration of anti-CXCL16 Ab protected the mice from death and acute liver damage. Approximately 70% of the mice survived for 72 h in the anti-CXCL16 Ab treatment group, whereas 80% died within 72 h in control Ab group. The number of liver-infiltrating T lymphocytes was significantly reduced from 1.01×10^7 to 3.52×10^6/liver, compared with control Ab treatment. CONCLUSION: CXCL16 is involved in immunological liver injury by regulating T lymphocyte infiltration in liver tissue.展开更多
AIM: To explore the alterations of intestinal mucosa morphology, and the effects of tumor necrosis factor a (TNFα) on enterocyte apoptosis in mice with fulminant hepatic failure (FHF). METHODS: Liver damage was induc...AIM: To explore the alterations of intestinal mucosa morphology, and the effects of tumor necrosis factor a (TNFα) on enterocyte apoptosis in mice with fulminant hepatic failure (FHF). METHODS: Liver damage was induced by lipopolysaccharide (LPS)/TNF-α in D-galactosamine (GaIN) sensitized BALB/c mice. There were 40 mice in normal saline (NS)-treated group, 40 mice in LPS-treated group, 40 mice in GaIN-treated group, 120 mice in GaIN/ LPS-treated group and 120 mice in GaIN/ TNFα-treated group. Each group was divided into five subgroups of eight mice each. Serum samples and liver, intestinal tissues were respectively obtained at 2, 6,9,12 and 24 h after administration. Anti-TNFa monoclonal antibody was injected intravenously into GaIN/LPS-treated mice. Serum TNFα levels were determined by enzyme linked immunosorbent assays (ELISA). Serum ALT levels were determined using an automatic analyzer. The intestinal tissues were studied under light microscope and electron microscope at 2, 6, 9,12 and 24 h in mice with fulminant hepatic failure, respectively. Enterocyte apoptosis was determined by terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) method. The expression of tumor necrosis factor receptor 1 (TNFR1) in intestinal tissue was tested by immunohistochemistry Envision Two Steps. RESULTS: Gut mucosa was morphologically normal at all time points in all groups, but typical apoptotic cells could be seen in all experimental groups under electron microscope. Apoptosis rate of gut mucosal epithelial cells were significantly increased at 6, 9 and 12 h, peaked at 12 h in mice with fulminant hepatic failure. TNFa induced apoptosis of enterocytes in mice with FHF. The integrated OD (IOD) levels of TNFa receptor 1 protein expressed in the intestine of mice with GaIN/LPS and GaIN/ TNFα induced FHF at 2, 6, 9, 12 and 24 h after GaIN/LPS and GaIN/TNFα administration were 169.54±52.62/905.79±111.84,11 350.67±2 133.26/28 160.37±4 601.67, 25 781.00±2 277.75/122 352.30±49 412.40, 5 241.53±3 007.24/ 49 157.93±9 804.88, 7 086.13±1 031.15/3 283.45±127.67, respectively, compared with those in control groups (with NS, LPS and GaIN administration, respectively). IOD level of TNFR1 changed significantly at 6, 9 and 12 h after GaIN/LPS and GalN/TNFa administration. The expression of TNFR1 protein was significantly higher at 9 h after GaIN/LPS and GaIN/TNFα administration than that in control groups. Protein expression of TNFR1 was positively correlated with enterocyte apoptosis. CONCLUSION: TNFα can induce apoptosis of enterocytes in mice with FHF. Anti-TNFα IgG can inhibit this role.展开更多
AIM: To study the effects and possible mechanisms of fufanghuangqiduogan (FFHQ) in mice with acute liver injury (ALI). METHODS: ALI was successfully induced by injecting carbon tetrachloride (CCl4) intra peritoneally ...AIM: To study the effects and possible mechanisms of fufanghuangqiduogan (FFHQ) in mice with acute liver injury (ALI). METHODS: ALI was successfully induced by injecting carbon tetrachloride (CCl4) intra peritoneally and by tail vein injection of Bacillus Calmette Guerin (BCG) and lipopolysaccharide (LPS) in mice, respectively. Each of the two model groups was divided into normal group, model group, FFHQ (60, 120 and 240 mg/kg) treatment groups, and bifendate treatment group. At the end of the experiment, levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), content of malondialdehyde (MDA), activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in liver homogenate were measured by biochemical methods. The activities of tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1) were determined by radio-immunoassay. Hepatic tissue sections were stained with hematoxylin and eosin and examined under a light microscope. RESULTS: In the two models of ALI, FFHQ (60, 120, 240 mg/kg) was found to significantly decrease the serum transaminase (ALT, AST) activities. Meanwhile, FFHQ decreased MDA contents and upregulated the lower SOD and GSH-px levels in liver homogenate. Furthermore, in immunologic liver injury model, FFHQ decreased levels of TNF-α and IL-1 in serum. Histologic examination showed that FFHQ could attenuate the area and extent of necrosis, reduce the immigration of inflammatory cells. CONCLUSION: FFHQ had protective effect on liver injury induced by either CCl4 or BCG+LPS in mice, and its mechanisms were related to free radical scavenging, increasing SOD and GSH-px activities and inhibiting the production of proinflammatory mediators.展开更多
AIM: To explore a simple, effective, safe and operable pretreatment for conferring tolerance against ischemia- reperfusion (I-R) injury in rat livers. METHODS: Forty-five rats were divided into five groups (each ...AIM: To explore a simple, effective, safe and operable pretreatment for conferring tolerance against ischemia- reperfusion (I-R) injury in rat livers. METHODS: Forty-five rats were divided into five groups (each group n = 9). Group C: control group; group G: geranylgeranylacetone (GGA) was administered without heat stress; group S: local heat stress alone; group WG: GGA plus whole-body heat stress; group SG: GGA administration plus local heat stress. After completion of the I-R procedure, the ischemic-reperfused liver lobes in five groups were resected and tested for heat shock protein (HSP70) by RT-PCR, Western blotting analysis and immunohistochemical staining. The blood samples were collected for ALT and AST measurement at the end of occlusion of blood supply, 30 min after reperfusion, 24, 48, 72 h after surgery from the inferior vena cava. Survival was monitored for 1 wk. RESULTS: The production of HSP70 after I-R injury increased, the liver enzyme levels after reperfusion decreased rapidly, and the survival rates increased in groups C-SG. CONCLUSION: The combination of GGA plus local somatothermal stimulation is a simple, effective, safe and operable pretreatment to induce HSP70 in patients with liver tumor and cirrhosis before hepatectomy and in donors before harvesting graft for liver transplantation.2005 The WJG Press and Elsevier Inc. All rights reserved.展开更多
AIM: There is increasing evidence that alcohol-induced liverdamage may be associated with increased oxidative stress.We aimed to investigate free-radical scavenger effect of n-acetylcysteine in rats intragastrically f...AIM: There is increasing evidence that alcohol-induced liverdamage may be associated with increased oxidative stress.We aimed to investigate free-radical scavenger effect of n-acetylcysteine in rats intragastrically fed with ethanol.METHODS: Twenty-four rats divided into three groups werefed with ethanol (6 g/kg/day, Group 1), ethanol and n-acetylcysteine (1 g/kg, Group 2), or isocaloric dextrose(control group, Group 3) for 4 weeks. Then animals weresacrificed under ether anesthesia, intracardiac blood andliver tissues were obtained. Measurements were performedboth in serum and in homogenized liver tissues.Malondialdehyde (MDA) level was measured by TBARSmethod. Glutathione peroxidase (GSH-Px) and superoxidedismutase (SOD) levels were studied by commercial kits.Kruskal-Wallis test was used for statistical analysis.RESULTS: ALT and AST in Group 1 (154 U/Land 302 U/L,respectively) were higher than those in Group 2 (94 U/L and155 U/L) and Group 3 (99 U/L and 168 U/L) (P=0.001 forboth). Serum and tissue levels of MDA in Group 1 (1.84 nmol/mL and 96 nmol/100 mg-protein) were higher than Group 2(0.91 nmol/mL and 64 nmol/100 mg-protein) and Group 3(0.94 nmol/mL and 49 nmol/100 mg-protein) (P<0.001 forboth). On the other hand, serum GSH-Px level in Group 1(8.21 U/g-Hb) was lower than Group 2 (16 U/g-Hb) andGroup 3 (16 U/g-Hb) (P<0.001). Serum and liver tissue levelsof SOD in Group 1 (11 U/mL and 26 U/100 mg-protein)were lower than Group 2 (18 U/mL and 60 U/100 mg-protein)and Group 3 (20 U/mL and 60 U/100 mg-protein) (P<0.001for both).CONCLUSION: This study demonstrated that ethanol-induced liver damage is associated with oxidative stress,and co-administration of n-acetylcysteine attenuates thisdamage effectively in rat model.展开更多
AIM: CMU-1 is a new preservation solution with a low potassium concentration as well as low viscosity that is highly effective in reducing preservation injury. The purpose of this experiment is to compare the protecti...AIM: CMU-1 is a new preservation solution with a low potassium concentration as well as low viscosity that is highly effective in reducing preservation injury. The purpose of this experiment is to compare the protective effect of CMU-1 solution with that of UW during cold preservation and normothermic reperfusion. METHODS: Wistar rats were divided into two groups according to different preservation solution: CMU-1 group and UW group. After 6, 12 and 24 h cold storage of rat liver in different preservation solutions, the isolated perfused rat liver model was applied to reperfuse the liver for 120 min normothermically (37 癈) with Krebs-Henseleit solution, meanwhile the pH value of the preservation solution was measured. The perfusate was sampled for the evaluation of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH). At the end of the reperfusion, all of the bile product was collected, energy metabolic substrate and histological examination were performed. RESULTS: After preserving for 6 h, pH value of both groups did not change; after 12 h, both decreased but with no significant difference. After 24 h, pH value in UW solution group significantly decreased. The total adenine nucleotides level and AEC in liver tissue decreased with preservation time, but they were higher in CMU-1 group. And the amount of bile product after perfusion for 120 min in CMU-1 group was much more than that in UW group. However, there were no significant differences in ALT and LDH levels between two groups. Histology showed no difference. CONCLUSION: The preservation effect of CMU-1 solution is similar with that of UW solution. However, CMU-1 solution shows some advantages over UW solution in energy metabolism, preventing intracellular acidosis and bile product.展开更多
Objective: To investigate whether nitric oxide synthase (NOS) is expressed in T-cell-dependent liver injury initiated by concanavalin A (ConA) in Kunming mice and study the possible effect of nitric oxide(NO) on liver...Objective: To investigate whether nitric oxide synthase (NOS) is expressed in T-cell-dependent liver injury initiated by concanavalin A (ConA) in Kunming mice and study the possible effect of nitric oxide(NO) on liver injury models. Methods: Liver injury in Kunming mice was induced by administration of ConA through tail vein. Expression of NOS in the liver was detected by NADPH diaphorase staining method. The possible effect of NO on liver injury models was obtained by L-NAME injection to suppress synthesis of NO. Results: NOS has a strong expression in hepatocytes after ConA injection, especially in those close to the central vein, while only a weak expression was found in the epithelial cells in control group. Liver injury became more serious when NO synthesis was inhibited by L-NAME, accompanied by great malondialdehyde(MDA) increase in serum and severe intrahepatic vascular thrombosis. Conclusion: NOS markedly expressed in ConA-induced liver injury, which may subsequently promote nitric oxide synthesis. Increasement of nitric oxide has a protective effect on ConA-induced liver injury.展开更多
Objective: To investigate the expression of early growth response gene-1(Egr-1) in the liver following hemorrhagic shock with or without resuscitation(HS or HSR). Methods: Mice were subjected to HS or HSR.Liver expres...Objective: To investigate the expression of early growth response gene-1(Egr-1) in the liver following hemorrhagic shock with or without resuscitation(HS or HSR). Methods: Mice were subjected to HS or HSR.Liver expression of Egr-1 mRNA was detected by Northern blotting.DNA binding activity of the Egr-1 protein in liver nuclear extracts(NE) was determined by electrophoretic mobility shift assay(EMSA).Western blot analysis was used to assess the induction of Egr-1 protein in the liver tissue,cytoplasma and NE. Results: Egr-1 mRNA was strongly expressed as early as 1 h after HS,and its level was decreased in the following 2.5 h but still higher than that in 1 h HS group.The Egr-1 DNA binding activity elevated in the liver NE of 2.5 h HS group and 2.5 h HS + 4 h R group,so did the Egr-1 protein in the liver and the liver NE of the same two groups.However,the maximal Egr-1 protein expression was found in the cytoplasma of liver following 2.5 h HS. Conclusion: Our data suggest that both Egr-1 mRNA and protein are strongly elevated and the binding activity of Egr-1 to its cognate DNA site is increased in the liver following HSR,indicating the increases of Egr-1 transcriptional and translational levels.This study provides evidence that Egr-1 gene is activated in the liver during HS and HSR.展开更多
AIM: To identify the proportion, causes and the nature of drug-induced liver injury (DILI) in patients with no- tably elevated alanine aminotransferase (ALT). METHODS: All the inpatients with ALT levels above 10...AIM: To identify the proportion, causes and the nature of drug-induced liver injury (DILI) in patients with no- tably elevated alanine aminotransferase (ALT). METHODS: All the inpatients with ALT levels above 10 times upper limit of normal range (ULN) were ret- rospectively identified from a computerized clinical laboratory database at our hospital covering a 12-mo period. Relevant clinical information was obtained from medical records. Alternative causes of ALT eleva- tions were examined for each patient, including bili- ary abnormality, viral hepatitis, hemodynamic injury, malignancy, DILI or undetermined and other causes. All suspected DILI cases were causality assessed usingthe Council for International Organizations of Medical Sciences scale, and only the cases classified as highly probable, probable, or possible were diagnosed as DILI. Comments related to the diagnosis of DILI in the medical record and in the discharge letter for each case were also examined to evaluate DILI detection by the treating doctors. RESULTS: A total of 129 cases with ALT 〉 i0 ULN were identified. Hemodynamic injury (n = 46, 35.7%), DILl (n = 25, 19.4%) and malignancy (n = 21, 16.3%) were the top three causes of liver injury. Peak ALT val- ues were lower in DILI patients than in patients with hemodynamic injury (14.5 5.6 ULN vs 32.5 :I: 30.7 ULN, P = 0.001). Among DILI patients, one (4%) case was classified as definite, 19 (76%) cases were clas- sified as probable and 5 (20%) as possible according to the ClOMS scale. A hepatocellular pattern was ob- served in 23 (92%) cases and mixed in 2 (8%). The extent of severity of liver injury was mild in 21 (84%) patients and moderate in 4 (16%). Before discharge, 10 (40%) patients were recovered and the other 15 (60%) were improved. The improved patients tended to have a higher peak ALT (808 + 348 U/L vs 623 + 118 U/L, P = 0.016) and shorter treatment duration before discharge (8 + 6 d vs 28 ~ 12 d, P = 0.008) compared with the recovered patients. Twenty-two drugs and 6 herbs were found associated with DILl. Antibacterials were the most common agents causing DILI in 8 (32%) cases, followed by glucocorticoids in 6 (24%) cases. Twenty-four (96%) cases received treatment of DILl with at least one adjunctive drug. Agents for treatment of DILI included anti-inflammatory drugs (e.g., glycyr- rhizinate), antioxidants (e.g., glutathione, ademetionine 1,4-butanedisulfonate and tiopronin), polyene phospha- tidyl choline and herbal extracts (e.g., protoporphyrin disodium and silymarin). Diagnosis of DILl was not mentioned in the discharge letter in 60% of the cases. Relative to prevalent cases and cases from wards of internal medicine, incident cases and cases from surgi- cal wards had a higher risk of missed diagnosis in dis- charge letter [odds ratio (OR) 32.7, 95%CI (2.8-374.1),CONCLUSION: DILI is mostly caused by use of anti- bacterials and glucocorticoids, and constitutes about one fifth of hospitalized patients with ALT 〉 10 ULN. DILI is underdiagnosed frequently.展开更多
文摘AIM:To explore a method to establish an animal model of ischemic type intrahepatic biliary lesion in rabbits. METHODS:Forty Japanese white rabbits of clean grade were divided randomly into four groups(10 rabbits per group)including sham operation(SO) group,and artery-bile obstruction(ABO)-1 h group, ABO-2 h group and ABO-3 h group.All the rabbits in this study underwent the same initial surgical procedure in which the liver was prepared as for graft removal during liver transplantation.Subsequently in the SO group,no additional vascular intervention was performed,while in groups ABO-1 h,ABO-2 h and ABO-3 h,the animals underwent combined clamping of the hepatic artery and common bile duct with microvascular clips for 1,2 and 3 h,respectively.After the scheduled occlusion time,the clip was removed to recover blood supply.The animals were killed 4 wk after operation.The survival rate,liver function, cholangiography and histopathological manifestation of the rabbits in each group were observed. RESULTS:The survival rate was 100%in groups SO,ABO-1 h and ABO-2 h,while it was 60%in group ABO-3 h.At each observation time,the change degree of the indexes of liver function was proportional to the clamping time(ABO-3 h>ABO-2 h>ABO-1 h> SO,P<0.05).Cholangiographical and histopathologic manifestations both showed that intrahepatic biliary lesion aggravated proportionally with the increase of the clamping time. CONCLUSION:An animal model of ischemic type intrahepatic biliary lesion in rabbits is successfully established,which may provide a reliable technique for basic and clinical research into the etiology, development and prophylaxis of ischemic type intrahepatic biliary lesion after liver transplantation.
基金Supported by the Universidad de Buenos Aires (Argentina) and Consejo Nacional de Investigaciones Cientificas y Tecnicas Argentina
文摘AIM: To evaluate the in vivo effect of glutamine on cobaltgenerated oxidative stress and (HO-1) induction in rat liver.METHODS: Fasted female Wistar rats received a single injection of cobalt chloride (375 μmol/kg body weight) and then were killed at different times. Lipid peroxidation and soluble and enzymatic antioxidant defense system (reduced glutathione (GSH), catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD)) were measured in liver homogenates. Ferritin and ferritin iron contents as well as heme oxygenase-1 (HO-1) activity and expression were also determined. The antioxidant properties of glutamine (Gin) were also evaluated. RESULTS: Cobalt chloride increased lipid peroxidation (50% over control values) 1 h after treatment. GSH reached a minimum at 3 h (40%) increasing thereafter. Twelve hours after CoCl2 injection, the antioxidant enzymes CAT, GSH-Px and SOD also diminished by about 30%. Heme oxygenase-1 induction was observed 6 h after treatment reaching a maximum value of 14-fold over the controls, 12 h after cobalt treatment. A 1.7-fold increase in ferritin and ferritin-bound iron 24 h after treatment were also obtained. Administration of glutamine (300 mg/kg body weight) by gavage 24 h before CoCl2 treatment entirely prevented the increase in thiobarbituric acid reactive substances (TBARS) content, the decrease in GSH levels, and partially reverted heme oxygenase-1 induction. CONCLUSION: These results suggested that a natural product such as glutamine prevents glutathione depletion and consequently heme oxygenase induction.
基金Supported in part by Grant-in-Aid for Scientific Research No. 17590615 to K. T. from Japan Society for the Promotion of Science
文摘AIM: To elucidate the mechanisms of hepatocyte preconditioning by H2O2 to better understand the pathophysiology of ischemic preconditioning. METHODS: The in vitro effect of H2O2 pretreatment was investigated in rat isolated hepatocytes subjected to anoxia/reoxygenation. Cell viability was assessed with propidium iodide fluorometry. In other experiments, rat livers were excised and subjected to warm ischemia/ reperfusion in an isolated perfused liver system to determine leakage of liver enzymes. Preconditioning was performed by H2O2 perfusion, or by stopping the perfusion for 10 min followed by 10 min of reperfusion. To inhibit Kupffer cell function or reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, gadolinium chloride was injected prior to liver excision, or diphenyleneiodonium, an inhibitor of NADPH oxidase, was added to the perfusate, respectively. Histological detection of oxygen radical formation in Kupffer cells was performed by perfusion with nitro blue tetrazolium. RESULTS: Anoxia/reoxygenation decreased hepatocyte viability compared to the controls. Pretreatment with H2O2 did not improve such hepatocyte injury. In liver perfusion experiments, however, H2O2 preconditioning reduced warm ischemia/reperfusion injury, which wasreversed by inhibition of Kupffer cell function or NADPH oxidase. Histological examination revealed that H2O2 preconditioning induced oxygen radical formation in Kupffer cells. NADPH oxidase inhibition also reversed hepatoprotection by ischemic preconditioning. CONCLUSION: H2O2 preconditioning protects hepato- cytes against warm ischemia/reperfusion injury via NADPH oxidase in Kupffer cells, and not directly. NADPH oxidase also mediates hepatoprotection by ischemic preconditioning.
基金Supported by the National Natural Science Foundation of China,No. 30230320National Science Fund for Distinguished Young Scholars from NSFC, No. 39925031National High Technology Research and Development Program of China, 863 grant 2004 AA215242Major State Basic Research Development Program of China, No. 2001CB510005partially by E-Institute of Shanghai Universities
文摘AIM: To investigate the role of CXCL16 in the pathogenesis of immunological liver injury and to explore the possible mechanism ofT lymphocyte infiltration regulated by CXCL16. METHODS: Immunological liver injury in murine model was induced by Bacille Calmette-Guerin and lipopolysaccharide. Expression pattern and distribution of CXCL16 were examined by real-time quantitative RT-PCR and immunohistochemical analysis. Anti-CXCL16 antibody was administrated in vivo to investigate its effect on T-cell recruitment and acute hepatic necrosis. The survival of murine model was also evaluated. RESULTS, The murine immunological liver injury model was successfully established, CXCL16 expression increased and predominantly distributed in periportal areas and vascular endothelia in injured liver tissues. Administration of anti-CXCL16 Ab protected the mice from death and acute liver damage. Approximately 70% of the mice survived for 72 h in the anti-CXCL16 Ab treatment group, whereas 80% died within 72 h in control Ab group. The number of liver-infiltrating T lymphocytes was significantly reduced from 1.01×10^7 to 3.52×10^6/liver, compared with control Ab treatment. CONCLUSION: CXCL16 is involved in immunological liver injury by regulating T lymphocyte infiltration in liver tissue.
基金Supported by Research Foundation of Ministry of Public Health, No. 97100252
文摘AIM: To explore the alterations of intestinal mucosa morphology, and the effects of tumor necrosis factor a (TNFα) on enterocyte apoptosis in mice with fulminant hepatic failure (FHF). METHODS: Liver damage was induced by lipopolysaccharide (LPS)/TNF-α in D-galactosamine (GaIN) sensitized BALB/c mice. There were 40 mice in normal saline (NS)-treated group, 40 mice in LPS-treated group, 40 mice in GaIN-treated group, 120 mice in GaIN/ LPS-treated group and 120 mice in GaIN/ TNFα-treated group. Each group was divided into five subgroups of eight mice each. Serum samples and liver, intestinal tissues were respectively obtained at 2, 6,9,12 and 24 h after administration. Anti-TNFa monoclonal antibody was injected intravenously into GaIN/LPS-treated mice. Serum TNFα levels were determined by enzyme linked immunosorbent assays (ELISA). Serum ALT levels were determined using an automatic analyzer. The intestinal tissues were studied under light microscope and electron microscope at 2, 6, 9,12 and 24 h in mice with fulminant hepatic failure, respectively. Enterocyte apoptosis was determined by terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) method. The expression of tumor necrosis factor receptor 1 (TNFR1) in intestinal tissue was tested by immunohistochemistry Envision Two Steps. RESULTS: Gut mucosa was morphologically normal at all time points in all groups, but typical apoptotic cells could be seen in all experimental groups under electron microscope. Apoptosis rate of gut mucosal epithelial cells were significantly increased at 6, 9 and 12 h, peaked at 12 h in mice with fulminant hepatic failure. TNFa induced apoptosis of enterocytes in mice with FHF. The integrated OD (IOD) levels of TNFa receptor 1 protein expressed in the intestine of mice with GaIN/LPS and GaIN/ TNFα induced FHF at 2, 6, 9, 12 and 24 h after GaIN/LPS and GaIN/TNFα administration were 169.54±52.62/905.79±111.84,11 350.67±2 133.26/28 160.37±4 601.67, 25 781.00±2 277.75/122 352.30±49 412.40, 5 241.53±3 007.24/ 49 157.93±9 804.88, 7 086.13±1 031.15/3 283.45±127.67, respectively, compared with those in control groups (with NS, LPS and GaIN administration, respectively). IOD level of TNFR1 changed significantly at 6, 9 and 12 h after GaIN/LPS and GalN/TNFa administration. The expression of TNFR1 protein was significantly higher at 9 h after GaIN/LPS and GaIN/TNFα administration than that in control groups. Protein expression of TNFR1 was positively correlated with enterocyte apoptosis. CONCLUSION: TNFα can induce apoptosis of enterocytes in mice with FHF. Anti-TNFα IgG can inhibit this role.
基金Supported by the State High Technology Research and Development Program of China (863 Program), No. 2002AA2Z3235
文摘AIM: To study the effects and possible mechanisms of fufanghuangqiduogan (FFHQ) in mice with acute liver injury (ALI). METHODS: ALI was successfully induced by injecting carbon tetrachloride (CCl4) intra peritoneally and by tail vein injection of Bacillus Calmette Guerin (BCG) and lipopolysaccharide (LPS) in mice, respectively. Each of the two model groups was divided into normal group, model group, FFHQ (60, 120 and 240 mg/kg) treatment groups, and bifendate treatment group. At the end of the experiment, levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), content of malondialdehyde (MDA), activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in liver homogenate were measured by biochemical methods. The activities of tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1) were determined by radio-immunoassay. Hepatic tissue sections were stained with hematoxylin and eosin and examined under a light microscope. RESULTS: In the two models of ALI, FFHQ (60, 120, 240 mg/kg) was found to significantly decrease the serum transaminase (ALT, AST) activities. Meanwhile, FFHQ decreased MDA contents and upregulated the lower SOD and GSH-px levels in liver homogenate. Furthermore, in immunologic liver injury model, FFHQ decreased levels of TNF-α and IL-1 in serum. Histologic examination showed that FFHQ could attenuate the area and extent of necrosis, reduce the immigration of inflammatory cells. CONCLUSION: FFHQ had protective effect on liver injury induced by either CCl4 or BCG+LPS in mice, and its mechanisms were related to free radical scavenging, increasing SOD and GSH-px activities and inhibiting the production of proinflammatory mediators.
文摘AIM: To explore a simple, effective, safe and operable pretreatment for conferring tolerance against ischemia- reperfusion (I-R) injury in rat livers. METHODS: Forty-five rats were divided into five groups (each group n = 9). Group C: control group; group G: geranylgeranylacetone (GGA) was administered without heat stress; group S: local heat stress alone; group WG: GGA plus whole-body heat stress; group SG: GGA administration plus local heat stress. After completion of the I-R procedure, the ischemic-reperfused liver lobes in five groups were resected and tested for heat shock protein (HSP70) by RT-PCR, Western blotting analysis and immunohistochemical staining. The blood samples were collected for ALT and AST measurement at the end of occlusion of blood supply, 30 min after reperfusion, 24, 48, 72 h after surgery from the inferior vena cava. Survival was monitored for 1 wk. RESULTS: The production of HSP70 after I-R injury increased, the liver enzyme levels after reperfusion decreased rapidly, and the survival rates increased in groups C-SG. CONCLUSION: The combination of GGA plus local somatothermal stimulation is a simple, effective, safe and operable pretreatment to induce HSP70 in patients with liver tumor and cirrhosis before hepatectomy and in donors before harvesting graft for liver transplantation.2005 The WJG Press and Elsevier Inc. All rights reserved.
基金the research Fund of the University of Istanbul.No: T-589/240698
文摘AIM: There is increasing evidence that alcohol-induced liverdamage may be associated with increased oxidative stress.We aimed to investigate free-radical scavenger effect of n-acetylcysteine in rats intragastrically fed with ethanol.METHODS: Twenty-four rats divided into three groups werefed with ethanol (6 g/kg/day, Group 1), ethanol and n-acetylcysteine (1 g/kg, Group 2), or isocaloric dextrose(control group, Group 3) for 4 weeks. Then animals weresacrificed under ether anesthesia, intracardiac blood andliver tissues were obtained. Measurements were performedboth in serum and in homogenized liver tissues.Malondialdehyde (MDA) level was measured by TBARSmethod. Glutathione peroxidase (GSH-Px) and superoxidedismutase (SOD) levels were studied by commercial kits.Kruskal-Wallis test was used for statistical analysis.RESULTS: ALT and AST in Group 1 (154 U/Land 302 U/L,respectively) were higher than those in Group 2 (94 U/L and155 U/L) and Group 3 (99 U/L and 168 U/L) (P=0.001 forboth). Serum and tissue levels of MDA in Group 1 (1.84 nmol/mL and 96 nmol/100 mg-protein) were higher than Group 2(0.91 nmol/mL and 64 nmol/100 mg-protein) and Group 3(0.94 nmol/mL and 49 nmol/100 mg-protein) (P<0.001 forboth). On the other hand, serum GSH-Px level in Group 1(8.21 U/g-Hb) was lower than Group 2 (16 U/g-Hb) andGroup 3 (16 U/g-Hb) (P<0.001). Serum and liver tissue levelsof SOD in Group 1 (11 U/mL and 26 U/100 mg-protein)were lower than Group 2 (18 U/mL and 60 U/100 mg-protein)and Group 3 (20 U/mL and 60 U/100 mg-protein) (P<0.001for both).CONCLUSION: This study demonstrated that ethanol-induced liver damage is associated with oxidative stress,and co-administration of n-acetylcysteine attenuates thisdamage effectively in rat model.
文摘AIM: CMU-1 is a new preservation solution with a low potassium concentration as well as low viscosity that is highly effective in reducing preservation injury. The purpose of this experiment is to compare the protective effect of CMU-1 solution with that of UW during cold preservation and normothermic reperfusion. METHODS: Wistar rats were divided into two groups according to different preservation solution: CMU-1 group and UW group. After 6, 12 and 24 h cold storage of rat liver in different preservation solutions, the isolated perfused rat liver model was applied to reperfuse the liver for 120 min normothermically (37 癈) with Krebs-Henseleit solution, meanwhile the pH value of the preservation solution was measured. The perfusate was sampled for the evaluation of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH). At the end of the reperfusion, all of the bile product was collected, energy metabolic substrate and histological examination were performed. RESULTS: After preserving for 6 h, pH value of both groups did not change; after 12 h, both decreased but with no significant difference. After 24 h, pH value in UW solution group significantly decreased. The total adenine nucleotides level and AEC in liver tissue decreased with preservation time, but they were higher in CMU-1 group. And the amount of bile product after perfusion for 120 min in CMU-1 group was much more than that in UW group. However, there were no significant differences in ALT and LDH levels between two groups. Histology showed no difference. CONCLUSION: The preservation effect of CMU-1 solution is similar with that of UW solution. However, CMU-1 solution shows some advantages over UW solution in energy metabolism, preventing intracellular acidosis and bile product.
文摘Objective: To investigate whether nitric oxide synthase (NOS) is expressed in T-cell-dependent liver injury initiated by concanavalin A (ConA) in Kunming mice and study the possible effect of nitric oxide(NO) on liver injury models. Methods: Liver injury in Kunming mice was induced by administration of ConA through tail vein. Expression of NOS in the liver was detected by NADPH diaphorase staining method. The possible effect of NO on liver injury models was obtained by L-NAME injection to suppress synthesis of NO. Results: NOS has a strong expression in hepatocytes after ConA injection, especially in those close to the central vein, while only a weak expression was found in the epithelial cells in control group. Liver injury became more serious when NO synthesis was inhibited by L-NAME, accompanied by great malondialdehyde(MDA) increase in serum and severe intrahepatic vascular thrombosis. Conclusion: NOS markedly expressed in ConA-induced liver injury, which may subsequently promote nitric oxide synthesis. Increasement of nitric oxide has a protective effect on ConA-induced liver injury.
文摘Objective: To investigate the expression of early growth response gene-1(Egr-1) in the liver following hemorrhagic shock with or without resuscitation(HS or HSR). Methods: Mice were subjected to HS or HSR.Liver expression of Egr-1 mRNA was detected by Northern blotting.DNA binding activity of the Egr-1 protein in liver nuclear extracts(NE) was determined by electrophoretic mobility shift assay(EMSA).Western blot analysis was used to assess the induction of Egr-1 protein in the liver tissue,cytoplasma and NE. Results: Egr-1 mRNA was strongly expressed as early as 1 h after HS,and its level was decreased in the following 2.5 h but still higher than that in 1 h HS group.The Egr-1 DNA binding activity elevated in the liver NE of 2.5 h HS group and 2.5 h HS + 4 h R group,so did the Egr-1 protein in the liver and the liver NE of the same two groups.However,the maximal Egr-1 protein expression was found in the cytoplasma of liver following 2.5 h HS. Conclusion: Our data suggest that both Egr-1 mRNA and protein are strongly elevated and the binding activity of Egr-1 to its cognate DNA site is increased in the liver following HSR,indicating the increases of Egr-1 transcriptional and translational levels.This study provides evidence that Egr-1 gene is activated in the liver during HS and HSR.
基金Supported by Zhejiang Provincial Bureau of Education,No.200908690Zhejiang Provincial Bureau of Health,No.2012KYA090
文摘AIM: To identify the proportion, causes and the nature of drug-induced liver injury (DILI) in patients with no- tably elevated alanine aminotransferase (ALT). METHODS: All the inpatients with ALT levels above 10 times upper limit of normal range (ULN) were ret- rospectively identified from a computerized clinical laboratory database at our hospital covering a 12-mo period. Relevant clinical information was obtained from medical records. Alternative causes of ALT eleva- tions were examined for each patient, including bili- ary abnormality, viral hepatitis, hemodynamic injury, malignancy, DILI or undetermined and other causes. All suspected DILI cases were causality assessed usingthe Council for International Organizations of Medical Sciences scale, and only the cases classified as highly probable, probable, or possible were diagnosed as DILI. Comments related to the diagnosis of DILI in the medical record and in the discharge letter for each case were also examined to evaluate DILI detection by the treating doctors. RESULTS: A total of 129 cases with ALT 〉 i0 ULN were identified. Hemodynamic injury (n = 46, 35.7%), DILl (n = 25, 19.4%) and malignancy (n = 21, 16.3%) were the top three causes of liver injury. Peak ALT val- ues were lower in DILI patients than in patients with hemodynamic injury (14.5 5.6 ULN vs 32.5 :I: 30.7 ULN, P = 0.001). Among DILI patients, one (4%) case was classified as definite, 19 (76%) cases were clas- sified as probable and 5 (20%) as possible according to the ClOMS scale. A hepatocellular pattern was ob- served in 23 (92%) cases and mixed in 2 (8%). The extent of severity of liver injury was mild in 21 (84%) patients and moderate in 4 (16%). Before discharge, 10 (40%) patients were recovered and the other 15 (60%) were improved. The improved patients tended to have a higher peak ALT (808 + 348 U/L vs 623 + 118 U/L, P = 0.016) and shorter treatment duration before discharge (8 + 6 d vs 28 ~ 12 d, P = 0.008) compared with the recovered patients. Twenty-two drugs and 6 herbs were found associated with DILl. Antibacterials were the most common agents causing DILI in 8 (32%) cases, followed by glucocorticoids in 6 (24%) cases. Twenty-four (96%) cases received treatment of DILl with at least one adjunctive drug. Agents for treatment of DILI included anti-inflammatory drugs (e.g., glycyr- rhizinate), antioxidants (e.g., glutathione, ademetionine 1,4-butanedisulfonate and tiopronin), polyene phospha- tidyl choline and herbal extracts (e.g., protoporphyrin disodium and silymarin). Diagnosis of DILl was not mentioned in the discharge letter in 60% of the cases. Relative to prevalent cases and cases from wards of internal medicine, incident cases and cases from surgi- cal wards had a higher risk of missed diagnosis in dis- charge letter [odds ratio (OR) 32.7, 95%CI (2.8-374.1),CONCLUSION: DILI is mostly caused by use of anti- bacterials and glucocorticoids, and constitutes about one fifth of hospitalized patients with ALT 〉 10 ULN. DILI is underdiagnosed frequently.