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Hepatic Injury (hepatic + injury)
Selected AbstractsComment on "Endothelially Derived Nitric Oxide Affects the Severity of Early Acetaminophen-induced Hepatic Injury in Mice"ACADEMIC EMERGENCY MEDICINE, Issue 9 2006Kari Scantlebury MD No abstract is available for this article. [source] Endothelially Derived Nitric Oxide Affects the Severity of Early Acetaminophen-induced Hepatic Injury in MiceACADEMIC EMERGENCY MEDICINE, Issue 5 2006Steven D. Salhanick MD Abstract Objectives: The precise mechanism of hepatocellular toxicity following acetaminophen (APAP) poisoning remains unclear. Nitric oxide is implicated in APAP toxicity as an inflammatory signaling molecule and as a precursor to the free radical peroxynitrate. The effects of inducible nitric oxide synthase (iNOS)-derived NO in APAP toxicity are known; however, the role of endothelial nitric oxide synthase (eNOS)-derived NO is unknown. The authors sought to evaluate the effect of eNOS-derived NO during APAP toxicity. Methods: C57BL6/J mice deficient in eNOS (eNOS KO) or iNOS (iNOS KO) and wild-type mice (WT) were treated with 300 mg/kg APAP. Alanine aminotransferase levels and plasma nitrate and nitrite levels were measured. Hypoxia inducible factor (HIF)-1, and Glucose Transporter 1 (Glut-1) levels were determined by Western blot. Results: Alanine aminotransferase levels were significantly elevated in all treated animals. Alanine aminotransferase levels were significantly lower in eNOS KO and iNOS KO than in treated WT animals. Plasma nitrate/nitrite levels were significantly higher in WT animals than in iNOS KO and eNOS KO animals. HIF-1, expression was increased in WT mice and decreased in iNOS KO mice. Glut-1 is a downstream, indirect marker of HIF function. Glut-1 expression was increased in WT and eNOS KO mice. Conclusions: Deficiency of either iNOS or eNOS results in decreased NO production and is associated with reduced hepatocellular injury following APAP poisoning. HIF-1, and Glut-1 levels are increased following APAP poisoning, implying that HIF-1, is functional during the pathogenic response to APAP poisoning. [source] Screening, Diagnosis, and Monitoring of Hepatic InjuryJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 10 2003ANP-C, FAANP, Mary Jo Goolsby EdD Although prophylactic vaccines and a better screened blood supply have contributed to a decreased incidence of viral hepatitis, liver injury remains a common problem. It is important that nurse practitioners know which patients are at risk for hepatic injury, when and how to screen for hepatic injury, and how to monitor patients diagnosed with hepatic damage. The National Academy of Clinical Biochemistry guidelines related to hepatic injury provide a framework for the screening, diagnosis, and monitoring of hepatic injury resulting from a variety of causes. [source] The Protective Effect of Bee Venom against Ethanol-Induced Hepatic Injury via Regulation of the Mitochondria-Related Apoptotic PathwayBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 1 2010Kyung-Hyun Kim Death of hepatocytes is a characteristic feature of chronic liver disease for various causes. Bee venom (Apis mellifera) has been traditionally used for the treatment of various chronic diseases, such as chronic inflammatory arthritis and chronic liver disease. However, the precise mechanism for bee venom in chronic liver disease is not still cleared. To assess the effects of bee venom in chronic liver disease, we investigated the potential role of the bee venom in the ethanol-induced hepatocyte apoptosis. Bee venom treatment inhibited the apoptotic cell morphology and increased the cell viability in ethanol-induced hepatocyte apoptosis. With ethanol treatment, bee venom-treated hepatocytes increased activity of Bcl-2 and Bcl-xL, reduced activity of Bax, Caspase and PARP. In conclusion, bee venom treatment in ethanol-induced hepatocyte apoptosis occurred through the regulation of Bcl family with subsequent inactivation of the Caspase and PARP. These results suggest that bee venom could be an effective agent to reduce ethanol-induced hepatocyte apoptosis. [source] Functional alterations of liver innate immunity of mice with aging in response to CpG-oligodeoxynucleotide,HEPATOLOGY, Issue 5 2008Toshinobu Kawabata Immune functions of liver natural killer T (NKT) cells induced by the synthetic ligand ,-galactosylceramide enhanced age-dependently; hepatic injury and multiorgan dysfunction syndrome (MODS) induced by ligand-activated NKT cells were also enhanced. This study investigated how aging affects liver innate immunity after common bacteria DNA stimulation. Young (6 weeks) and old (50-60 weeks) C57BL/6 mice were injected with CpG oligodeoxynucleotides (CpG-ODN), and the functions of liver leukocytes were assessed. A CpG-ODN injection into the old mice remarkably increased tumor necrosis factor (TNF) production in Kupffer cells, and MODS and lethal shock were induced, both of which are rarely seen in young mice. Old Kupffer cells showed increased Toll-like receptor-9 expression, and CpG-ODN challenge augmented TNF receptor and Fas-L expression in liver NKT cells. Experiments using mice depleted of natural killer (NK) cells by anti-asialoGM1 antibody (Ab), perforin knockout mice, and mice pretreated with neutralizing interferon (IFN)-, Ab demonstrated the important role of liver NK cells in antitumor immunity. The production capacities of old mice for IFN-,, IFN-,, and perforin were much lower than those of young mice, and the CpG-induced antitumor cytotoxicity of liver NK cells lessened. Lethal shock and MODS greatly decreased in old mice depleted/deficient in TNF, FasL, or NKT cells. However, depletion of NK cells also decreased serum TNF levels and FasL expression of NKT cells, which resulted in improved hepatic injury and survival, suggesting that NK cells are indirectly involved in MODS/lethal shock induced by NKT cells. Neutralization of TNF did not reduce the CpG-induced antitumor effect in the liver. Conclusion: Hepatic injury and MODS mediated by NKT cells via the TNF and FasL-mediated pathway after CpG injection increased, but the antitumor activity of liver NK cells decreased with aging. (HEPATOLOGY 2008.) [source] Improved rat steatotic and nonsteatotic liver preservation by the addition of epidermal growth factor and insulin-like growth factor-I to University of Wisconsin solutionLIVER TRANSPLANTATION, Issue 9 2010M. Amine Zaouali This study examined the effects of epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) supplementation to University of Wisconsin solution (UW) in steatotic and nonsteatotic livers during cold storage. Hepatic injury and function were evaluated in livers preserved for 24 hours at 4°C in UW and in UW with EGF and IGF-I (separately or in combination) and then perfused ex vivo for 2 hours at 37°C. AKT was inhibited pharmacologically. In addition, hepatic injury and survival were evaluated in recipients who underwent transplantation with steatotic and nonsteatotic livers preserved for 6 hours in UW and UW with EGF and IGF-I (separately or in combination). The results, based on isolated perfused liver, indicated that the addition of EGF and IGF-I (separately or in combination) to UW reduced hepatic injury and improved function in both liver types. A combination of EGF and IGF-I resulted in hepatic injury and function parameters in both liver types similar to those obtained by EGF and IGF-I separately. EGF increased IGF-I, and both additives up-regulated AKT in both liver types. This was associated with glycogen synthase kinase-3, (GSK3,) inhibition in nonsteatotic livers and PPAR, overexpression in steatotic livers. When AKT was inhibited, the effects of EGF and IGF-I on GSK3,, PPAR,, hepatic injury and function disappeared. The benefits of EGF and IGF-I as additives in UW solution were also clearly seen in the liver transplantation model, because the presence of EGF and IGF-I (separately or in combination) in UW solution reduced hepatic injury and improved survival in recipients who underwent transplantation with steatotic and nonsteatotic liver grafts. In conclusion, EGF and IGF-I may constitute new additives to UW solution in steatotic and nonsteatotic liver preservation, whereas a combination of both seems unnecessary. Liver Transpl 16:1098,1111, 2010. © 2010 AASLD. [source] Cytoprotection by bcl-2 gene transfer against ischemic liver injuries together with repressed lipid peroxidation and increased ascorbic acid in livers and serumJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 5 2004Shinobu Yanada Abstract The maximum gene exhibition was shown to be achieved at 48 h after transfection with human bcl-2 (hbcl-2) genes built in an SV40 early promoter-based plasmid vector and HVJ-liposome for cultured rat hepatocytes. The similar procedure of hbcl-2 transfection was therefore conducted for livers in rats via the portal vein, and after 48 h followed by post-ischemic reperfusion (I/R) operation for some hepatic lobes. The I/R-induced hepatic injuries were in situ observed as both cell morphological degeneration and cellular DNA strand cleavages around capillary vessels of the ischemic liver lobes as detected by HE stain and TUNEL assay, and were biochemically observed as release of two hepatic marker enzymes AST and ALT into serum. All the I/R-induced injuries examined were appreciably repressed for rats transfected with hbcl-2; hbcl-2 was expressed in hepatocytes around the capillaries of ischemic regions such as the median lobe and the left lobe, but scarcely around those of non-ischemic regions. Thus cytoprotection against I/R-induced injuries may be attributed to the I/R-promoted expression of transferred hbcl-2 genes. The possibility was examined firstly by methylphenylindole method, which showed that I/R-enhanced lipid peroxidation in the reference vector-transfected livers were markedly repressed in the hbcl-2 -transfected livers. Contents of ascorbic acid (Asc) in serum and livers of hbcl-2 -transfected rats were enriched, unexpectedly, versus those of non-transfected rats, and were as abundant as 1.90-fold and 1.95- to 2.60-fold versus those in the pre-ischemic state, respectively. After I/R, an immediate decline in serum Asc occurred in hbcl-2 -transfectants, and was followed by prompt restoration up to the pre-ischemic Asc levels in contrast to the unaltered lower Asc levels in non-transfectants except a transient delayed increase. Hepatic Asc contents were also diminished appreciably at the initial stage after I/R in the ischemic lobes of hbcl-2 -transfectants, which however retained more abundant Asc versus non-transfectants especially at the initial I/R stage when scavenging of the oxidative stress should be most necessary for cytoprotection. The results showed a close correlation between cytoprotection by exogenously transferred hbcl-2 and repressive effects on the lipid peroxidation associated with Asc consumption or redistribution. © 2004 Wiley-Liss, Inc. [source] Adverse drug reactions in medical intensive care unit of a tertiary care hospital,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 7 2009Lisha Joshua MBBS Abstract Purpose Patients in the intensive care unit (ICU) have multiorgan dysfunction as well as altered pharmacokinetic parameters. Hence they are susceptible to adverse drug reactions (ADRs). The objective of the study is to assess the characteristics of ADRs among inpatients in the medical ICU and to compare the same with patients who have not experienced ADRs. Methods Prospective, observational study for a period of 1 year in medical ICU of a tertiary care hospital. Relevant data of patients with ADRS were analysed. Characteristics of patients with and without ADRs were compared. Results Of 728 patients admitted in medical ICU, 222 (28.4%) had ADRs. Multiple ADRs (38.7%) implicated by the same drug and serious ADRs (37%) were noticed. Renal/electrolyte system (21%) was most commonly involved. Clinical spectrum included acute renal failure (ARF, 11.4%), hepatic injuries (5.4%), haematological dysfunction (4.2%), seizures (3.3%), upper gastrointestinal bleed (3.3%) and cutaneous ADRs (3.3%). Antimicrobials (27%) were the commonly implicated drug class. The most commonly implicated drug was furosemide (6.8%). Infrequently reported ADRs included azithromycin-induced erythema multiforme, leflunamide-induced erythema multiforme and vasculitis, ceftazidime-induced seizures and ceftriaxone-induced hepatitis. Co-morbidity, polypharmacy and duration of stay were significantly higher in patients with ADRs compared to those who have not experienced ADRs. Three patients died. Conclusion High incidence of serious and multiple ADRs noticed. A wide clinical spectrum of ADRs and infrequently reported ADRs to newer drugs were also observed. Copyright © 2009 John Wiley & Sons, Ltd. [source] High risk of hepatitis B-virus reactivation after hematopoietic cell transplantation in hepatitis B core antibody-positive patientsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2009Kosei Matsue Abstract We investigated the serological changes in hepatitis B virus (HBV)-related markers in 55 and 26 hepatitis B surface antigen (HBsAg)-negative patients undergoing allogeneic and autologous stem cell transplantation, respectively, over the past 4 yr. Five of the 17 allogeneic and one of the five autologous patients with pretransplant anti-hepatitis B core antigen antibodies (anti-HBc) were HBsAg-positive after transplantation, whereas none of the patients negative for anti-HBc were HBsAg-positive in both groups. All patients who became HBsAg-positive received steroid-containing immunosuppressive therapy for chronic graft versus host disease (GVHD) or myeloma. Four of the six patients developed flare of HBV hepatitis, and two patients did not. One patient developed fulminant hepatitis treated with lamivudine and plasma exchange. Other five patients received entecavir from the detection of HBsAg. Although HBV-DNA levels became below the limit of detection in all patients, HBsAg positivity remained in three patients after 6 months of treatment. We concluded that anti-HBc positivity is a risk factor for reactivation of HBV after both autologous and allogeneic transplantation, and HBV-related markers should be monitored regularly in these patients. We also stress the efficacy of pre-emptive use of antiviral agents in controlling HBV replication and limiting hepatic injury due to reactivation of HBV in these patients. [source] Adipokines in liver diseases,HEPATOLOGY, Issue 3 2009Fabio Marra Adipokines are polypeptides secreted in the adipose tissue in a regulated manner. While some of these molecules are expressed only by adipocytes, resident and infiltrating macrophages and components of the vascular stroma markedly contribute to expression of other adipokines. As a result, adipose tissue inflammation is associated with a modification in the pattern of adipokine secretion. Leptin, adiponectin, and resistin are the best-studied molecules in this class, but cytokines such as tumor necrosis factor or interleukin-6 are also secreted at high levels by the adipose tissue. Several other molecules have been recently identified and are actively investigated. Adipokines interfere with hepatic injury associated with fatty infiltration, differentially modulating steatosis, inflammation, and fibrosis. Several studies have investigated plasma levels of adiponectin in patients with nonalcoholic fatty liver disease, to establish correlations with the underlying state of insulin resistance and with the type and severity of hepatic damage. Hepatitis C is another disease where adipokines may represent a link between viral infection, steatosis, and metabolic disturbances. Identification of the mediators secreted by expanded adipose tissue and their pathogenic role is pivotal in consideration of the alarming increase in the prevalence of obesity and of the detrimental role that this condition exerts on the course of liver diseases. (HEPATOLOGY 2009.) [source] Functional alterations of liver innate immunity of mice with aging in response to CpG-oligodeoxynucleotide,HEPATOLOGY, Issue 5 2008Toshinobu Kawabata Immune functions of liver natural killer T (NKT) cells induced by the synthetic ligand ,-galactosylceramide enhanced age-dependently; hepatic injury and multiorgan dysfunction syndrome (MODS) induced by ligand-activated NKT cells were also enhanced. This study investigated how aging affects liver innate immunity after common bacteria DNA stimulation. Young (6 weeks) and old (50-60 weeks) C57BL/6 mice were injected with CpG oligodeoxynucleotides (CpG-ODN), and the functions of liver leukocytes were assessed. A CpG-ODN injection into the old mice remarkably increased tumor necrosis factor (TNF) production in Kupffer cells, and MODS and lethal shock were induced, both of which are rarely seen in young mice. Old Kupffer cells showed increased Toll-like receptor-9 expression, and CpG-ODN challenge augmented TNF receptor and Fas-L expression in liver NKT cells. Experiments using mice depleted of natural killer (NK) cells by anti-asialoGM1 antibody (Ab), perforin knockout mice, and mice pretreated with neutralizing interferon (IFN)-, Ab demonstrated the important role of liver NK cells in antitumor immunity. The production capacities of old mice for IFN-,, IFN-,, and perforin were much lower than those of young mice, and the CpG-induced antitumor cytotoxicity of liver NK cells lessened. Lethal shock and MODS greatly decreased in old mice depleted/deficient in TNF, FasL, or NKT cells. However, depletion of NK cells also decreased serum TNF levels and FasL expression of NKT cells, which resulted in improved hepatic injury and survival, suggesting that NK cells are indirectly involved in MODS/lethal shock induced by NKT cells. Neutralization of TNF did not reduce the CpG-induced antitumor effect in the liver. Conclusion: Hepatic injury and MODS mediated by NKT cells via the TNF and FasL-mediated pathway after CpG injection increased, but the antitumor activity of liver NK cells decreased with aging. (HEPATOLOGY 2008.) [source] Dose- and time-dependent oval cell reaction in acetaminophen-induced murine liver injury,HEPATOLOGY, Issue 6 2005Alexander V. Kofman We examined the response of murine oval cells, that is, the putative liver progenitor cells, to acetaminophen. Female C57BL/6J mice were injected intraperitoneally with varying doses of N -acetyl-paraaminophen (APAP) (250, 500, 750, and 1,000 mg/kg of weight) and sacrificed at 3, 6, 9, 24, and 48 hours. In preliminary studies, we showed that anticytokeratin antibodies detected A6-positive cells with a sensitivity and specificity of greater than 99%. The oval cell reaction was quantified, on immunostaining for biliary-type cytokeratins, as both number and density of oval cells per portal tract, analyzed by size of portal tract. Acetaminophen injury was followed by periportal oval cell accumulation displaying a moderate degree of morphological homogeneity. Oval cell response was biphasic, not temporally correlating with the single wave of injury seen histologically. Increases in oval cells were largely confined to the smallest portal tracts, in keeping with their primary derivation from the canals of Hering, and increased in a dose-dependent fashion. The timing of the two peaks of the oval cell reaction also changed with increasing dose, the first becoming earlier and the second later. In conclusion, our studies indicate a marked oval cell activation during the height of hepatic injury. Oval cells appear to be resistant to acetaminophen injury. The close fidelity of mechanism and histology of acetaminophen injury between mouse and human livers makes it a useful model for investigating liver regeneration and the participation of stem/progenitor cells in that process. (HEPATOLOGY 2005.) [source] Kupffer cell,derived interleukin 10 is responsible for impaired bacterial clearance in bile duct,ligated miceHEPATOLOGY, Issue 2 2004Tetsuya Abe Extrahepatic cholestasis often evokes liver injury with hepatocyte apoptosis, aberrant cytokine production, and,most importantly,postoperative septic complications. To clarify the involvement of aberrant cytokine production and hepatocyte apoptosis in impaired resistance to bacterial infection in obstructive cholestasis, C57BL/6 mice or Fas-mutated lpr mice were inoculated intraperitoneally with 107 colony-forming units of Escherichia coli 5 days after bile duct ligation (BDL) or sham celiotomy. Cytokine levels in sera, liver, and immune cells were assessed via enzyme-linked immunosorbent assay or real-time reverse-transcriptase polymerase chain reaction. BDL mice showed delayed clearance of E. coli in peritoneal cavity, liver, and spleen. Significantly higher levels of serum interleukin (IL) 10 with lower levels of IL-12p40 were observed in BDL mice following E. coli infection. Interferon , production from liver lymphocytes in BDL mice was not increased after E. coli infection either at the transcriptional or protein level. Kupffer cells from BDL mice produced low levels of IL-12p40 and high levels of IL-10 in vitro in response to lipopolysaccharide derived from E. coli. In vivo administration of anti,IL-10 monoclonal antibody ameliorated the course of E. coli infection in BDL mice. Furthermore, BDL- lpr mice did not exhibit impairment in E. coli killing in association with little hepatic injury and a small amount of IL-10 production. In conclusion, increased IL-10 and reciprocally suppressed IL-12 production by Kupffer cells are responsible for deteriorated resistance to bacterial infection in BDL mice. Fas-mediated hepatocyte apoptosis in cholestasis may be involved in the predominant IL-10 production by Kupffer cells. (HEPATOLOGY 2004;40:414,423.) [source] Adiponectin protects LPS-induced liver injury through modulation of TNF-, in KK-Ay obese miceHEPATOLOGY, Issue 1 2004Takayuki Masaki Adiponectin, an adipocytokine, has been identified in adipose tissue, and its receptors are widely distributed in many tissues, including the liver. The present study was performed to clarify the role of adiponectin in lipopolysaccharide (LPS)-induced liver injury using KK-Ay obese mice. We analyzed the effects of adiponectin pretreatment on liver injury induced by D -galactosamine/LPS (GalN/LPS) in KK-Ay obese mice. GalN/LPS treatment induced significant increases in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in the blood, apoptotic and necrotic changes in hepatocytes, and/or showed a high degree of lethality. The GalN/LPS-induced liver injury was more pronounced in KK-Ay obese mice than in lean controls. Pretreatment with adiponectin ameliorated the GalN/LPS-induced elevation of serum AST and ALT levels and the apoptotic and necrotic changes in hepatocytes, resulting in a reduction in lethality. In addition, pretreatment with adiponectin attenuated the GalN/LPS-induced increases in serum and hepatic tumor necrosis factor , (TNF-,) levels and increased peroxisome proliferator-activated receptor (PPAR) , messenger RNA expression in the liver. Furthermore, abdominal macrophages from KK-Ay obese mice pretreated with adiponectin in vitro exhibited decreased LPS-induced TNF-, production compared with controls. Finally, adiponectin pretreatment also ameliorated TNF-,-induced liver injury. In conclusion, these findings suggest that adiponectin prevents LPS-induced hepatic injury by inhibiting the synthesis and/or release of TNF-, of KK-Ay obese mice. (HEPATOLOGY 2004;40:177,184.) [source] Ischemic preconditioning affects interleukin release in fatty livers of rats undergoing ischemia/reperfusionHEPATOLOGY, Issue 3 2004Anna Serafín The present study evaluates the effect of ischemic preconditioning on interleukin-1 (IL-1) and interleukin-10 (IL-10) generation following hepatic ischemia/reperfusion (I/R) in normal and steatotic livers as well as the role of nitric oxide (NO) in this process. Increased IL-1, and IL-10 levels were observed in normal livers after I/R. Steatotic livers showed higher IL-1, levels than normal livers, and IL-10 at control levels. The injurious role of IL-1, and the benefits of IL-10 on hepatic I/R injury was shown with the use of IL-1 receptor antagonist (IL-1ra), anti-IL-10 polyclonal antibody against IL-10 (anti-IL-10) and exogenous IL-10. The effective dose of these treatments was different in both types of livers. Preconditioning prevented IL-1, release and increased IL-10 generation after I/R in normal and steatotic livers. IL-1, or anti-IL-10 pretreatments reversed the benefits of preconditioning. IL-1, action inhibition in a preconditioned group that was pretreated with anti-IL-10 did not modify the benefits of preconditioning. In addition, anti-IL-10 pretreatment in the preconditioned group resulted in IL-1, levels comparable to those observed after I/R. NO inhibition eliminated the benefits of preconditioning on IL-10 release, IL-1, levels, and hepatic injury. In conclusion, preconditioning, through IL-10 overproduction, inhibits IL-1, release and the ensuing hepatic I/R injury in normal and steatotic livers. IL-10 generation induced by preconditioning could be mediated by NO. (HEPATOLOGY 2004;39:688,698.) [source] Chronic alcohol consumption increases the sensitivity of rat liver mitochondrial respiration to inhibition by nitric oxideHEPATOLOGY, Issue 1 2003Aparna Venkatraman Chronic alcohol consumption is a well-known risk factor for hepatic injury, and mitochondrial damage plays a significant role in this process. Nitric oxide (NO) is an important modulator of mitochondrial function and is known to inhibit mitochondrial respiration. However, the impact of chronic alcohol consumption on NO-dependent control of liver mitochondrial function is unknown. This study examines the effect of alcohol exposure on liver mitochondria in a rat model and explores the interaction of NO and mitochondrial respiration in this context. Mitochondria were isolated from the liver of both control and ethanol-fed rats after 5 to 6 weeks of alcohol consumption. Mitochondria isolated from ethanol-treated rats showed a significant decrease in state 3 respiration and respiratory control ratio that was accompanied by an increased sensitivity to NO-dependent inhibition of respiration. In conclusion, we show that chronic alcohol consumption leads to increased sensitivity to the inhibition of respiration by NO. We propose that this results in a greater vulnerability to hypoxia and the development of alcohol-induced hepatotoxicity. [source] Stat4 and Stat6 signaling in hepatic ischemia/reperfusion injury in mice: HO-1 dependence of Stat4 disruption-mediated cytoprotectionHEPATOLOGY, Issue 2 2003Xiu-Da Shen Ischemia/reperfusion (I/R) injury remains an important problem in clinical organ transplantation. There is growing evidence that T lymphocytes, and activated CD4+ T cells in particular, play a key role in hepatic I/R injury. This study analyzes the role of signal transducer and activator of transcription 4 (Stat4) and Stat6 signaling in liver I/R injury. Using a partial lobar warm ischemia model, groups of wild-type (WT), T cell,deficient, Stat4-/Stat6-deficient knockout (KO) mice were assessed for the extent/severity of I/R injury. Ninety minutes of warm ischemia followed by 6 hours of reperfusion induced a fulminant liver failure in WT and Stat6 KO mice, as assessed by hepatocellular damage (serum alanine aminotransferase [sALT] levels), neutrophil accumulation (myeloperoxidase [MPO] activity) and histology (Suzuki scores). In contrast, T cell deficiency (nu/nu mice) or disruption of Stat4 signaling (Stat4 KO mice) reduced I/R insult. Unlike adoptive transfer of WT or Stat6-deficient T cells, infusion of Stat4-deficient T cells failed to restore hepatic I/R injury and prevented tumor necrosis factor , (TNF-,) production in nu/nu mice. Diminished TNF-,/Th1-type cytokine messenger RNA (mRNA)/protein elaborations patterns, along with overexpression of heme oxygenase-1 (HO-1),accompanied hepatic cytoprotection in Stat4 KO recipients. In contrast, HO-1 depression restored hepatic injury in otherwise I/R resistant Stat4 KOs. In conclusion, Stat4 signaling is required for, whereas Stat4 disruption protects against, warm hepatic I/R injury in mice. The cytoprotection rendered by Stat4 disruption remains HO-1,dependent. [source] Alcohol-induced free radicals in mice: Direct toxicants or signaling molecules?HEPATOLOGY, Issue 5 2001Ming Yin Tumor necrosis factor , (TNF-,) and free radicals are produced in early alcohol-induced liver injury. Recently, pathology caused by alcohol was blocked nearly completely in tumor necrosis factor , receptor 1 (TNF-R1) knockout mice. With this model, it is now possible to evaluate whether free radicals are directly toxic or act as redox regulators of TNF-, production. Specifically, if free radicals were directly toxic, a parallel decrease in free radicals and pathology in TNF-R1 knockout mice would be predicted. If they only affect TNF-, production, radicals would be expected to remain high while pathology is diminished. Accordingly, free radical production in TNF-R1 knockout mice was studied here. The enteral alcohol delivery model used mice lacking TNF-R1 (p55) and wild-type control C57Bl/6J mice. Animals received a liquid diet continuously with either ethanol or isocaloric maltose-dextrin as control for 4 weeks. Urine ethanol levels fluctuated from 10 to 500 mg/dL in a cyclic pattern in mice receiving ethanol. Ethanol elevated liver:body weight ratios, serum alanine transaminase (ALT) levels, and pathology scores in wild-type mice. These parameters were blunted nearly completely in TNF-R1 knockout mice. Ethanol treatment increased free radical production in wild-type mice compared with animals fed a high-fat control diet. There were no differences in intensity of free radical signals regardless of the presence or absence of TNF-R1; however, pathology differed markedly between these groups. These findings are consistent with the hypothesis that free radicals act as redox signals for TNF-, production and do not directly damage cells in early alcohol-induced hepatic injury. [source] Matrix metalloproteinase inhibitor, CTS-1027, attenuates liver injury and fibrosis in the bile duct-ligated mouseHEPATOLOGY RESEARCH, Issue 8 2009Alisan Kahraman Aim:, Excessive matrix metalloproteinase (MMP) activity has been implicated in the pathogenesis of acute and chronic liver injury. CTS-1027 is an MMP inhibitor, which has previously been studied in humans as an anti-arthritic agent. Thus, our aim was to assess if CTS-1027 is hepato-protective and anti-fibrogenic during cholestatic liver injury. Methods:, C57/BL6 mice were subjected to bile duct ligation (BDL) for 14 days. Either CTS-1027 or vehicle was administered by gavage. Results:, BDL mice treated with CTS-1027 demonstrated a threefold reduction in hepatocyte apoptosis as assessed by the TUNEL assay or immunohistochemistry for caspase 3/7-positive cells as compared to vehicle-treated BDL animals (P < 0.01). A 70% reduction in bile infarcts, a histological indicator of liver injury, was also observed in CTS-1027-treated BDL animals. These differences could not be ascribed to differences in cholestasis as serum total bilirubin concentrations were nearly identical in the BDL groups of animals. Markers for stellate cell activation (,-smooth muscle actin) and hepatic fibrogenesis (collagen 1) were reduced in CTS-1027 versus vehicle-treated BDL animals (P < 0.05). Overall animal survival following 14 days of BDL was also improved in the group receiving the active drug (P < 0.05). Conclusion:, The BDL mouse, liver injury and hepatic fibrosis are attenuated by treatment with the MMP inhibitor CTS-1027. This drug warrants further evaluation as an anti-fibrogenic drug in hepatic injury. [source] Differential expression of the genes involved in amino acids and nitrogen metabolisms during liver regeneration of miceHEPATOLOGY RESEARCH, Issue 3 2009Yunsheng Yuan Aim:, Liver regeneration is a highly coordinated response to hepatic injury or resection that is controlled by the body's overall requirement for liver function. The level of circulating amino acids in blood increases after acute liver injury and administration of amino acid mixtures induces hepatic DNA replication. These findings suggest a close connection between amino acid metabolism and hepatic proliferation. However, the underlying molecular mechanisms have not been completely elucidated. Here, we applied a cDNA micro-array technique to analyze expression profiles of the genes associated with nitrogen and amino acid metabolism during liver regeneration in mice following treatment with CCl4. Methods:, Seventy-nine genes were identified for their significantly altered expression patterns at different stages of liver damage and regeneration. Results:, We observed that the numbers of down-regulated genes were remarkably higher than that of up-regulated genes at 1.5 days following carbon tetrachloride administration when hepatic DNA replication was most active, indicating the existence of a counter balance between cell proliferation and liver metabolism functions. Conclusions:, Our results suggest that suppression of amino acids metabolism after acute liver injury results in the accumulation of amino acids in plasma that serves as a driving force for liver regeneration. [source] Protective effect of non-mitogenic human acidic fibroblast growth factor on hepatocyte injuryHEPATOLOGY RESEARCH, Issue 10 2007Hua Xu Aim:, To study whether non-mitogenic human acidic fibroblast growth factor (nm-haFGF) has protective effects on H2O2 -induced hepatocyte injury in vitro and CCl4 -induced hepatocyte injury in vivo. Methods:, (i) HL-7702 hepatocytes were incubated with different concentrations of nm-haFGF for 12 h, and then the activity of lactate dehydrogenase (LDH) in culture medium was detected, and genomic DNA electrophoresis analysis was observed after being exposed to H2O2 (8 mmol/L) for 4 h. Proximately, apoptotic rates and protein expressions of Bcl-2 and Bax of HL-7702 cell were detected after being exposed to H2O2 (0.2 mmol/L) for 20 h. (ii) Being injected intraperitoneally with nm-haFGF, mice were treated with CCl4 intraperitoneally to induce hepatic injury. Twenty-four hours later, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured and histopathologic changes were evaluated. Results:, (i) In vitro tests: LDH activities and apoptotic rates decreased, the protein expression of Bcl-2 increased and Baxdecreased in nm-haFGF-treated groups at the concentrations of 100 150 and 200 ng/mL, compared with that in the model control group, which was treated with H2O2 alone. The genomic DNA remained nearly intact at the concentrations of 150 and 200 ng/mL. (ii) In vivo tests: serum ALT and AST in nm-haFGF-treated groups (10 ,g/kg and 20 ,g/kg) were much lower as compared to the model control group, which was treated with CCl4 alone. Histological examination showed that nm-haFGF markedly ameliorated hepatocytes vacuolation, cloudy swelling and inflammatory cells infiltration induced by CCl4. Conclusion:, nm-haFGF had protective effects against H2O2 -induced hepatocyte injury in vitro and CCl4 -induced acute liver injury in vivo. [source] Interleukin-17 as a new marker of severity of acute hepatic injuryHEPATOLOGY RESEARCH, Issue 4 2007Yuki Yasumi Aim:, To determine cytokines associated with the progression of acute hepatic injury (AHI), we comprehensively evaluated the serum levels of 17 cytokines. Methods:, We simultaneously measured serum levels of 17 cytokines on admission using a newly developed suspension array protein assay system in 51 patients with AHI, including 15 conventional AHI (CAHI), 15 severe AHI (SAHI) and 21 fulminant hepatic failure (FHF). Results:, Interleukin (IL)-6, IL-8 and IL-17 levels were significantly different among the three disease types as determined by one-way analysis of variance, and only the IL-17 level showed a significant elevation in SAHI and FHF than in CAHI. Namely, the IL-17 levels in SAHI and FHF patients were 4.4 (2.0,11.0) (mean [1 .s.d. range]) and 5.6 (2.0,18.5) pg/mL, respectively, whereas all CAHI patients showed levels lower than the lower limit of detection (2.0 pg/mL). In multiple regression analysis for each factor of model for end-stage liver disease (MELD) score, only IL-10 level was selected as the significant independent variable for total bilirubin level, only IL-17 level for prothrombin time, and TNF-, and IL-1, levels for creatinine level. Conclusion:, These data suggest the usefulness of serum IL-17 level in evaluating the severity of AHI, thus emphasizing the necessity for the basic investigation of the pathological role of IL-17 in acute hepatitis. [source] Liver sinusoidal endothelial cells and acute non-oxidative hepatic injury induced by Pseudomonas aeruginosa pyocyaninINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 6 2008Rajkumar Cheluvappa Summary The liver sinusoidal endothelial cell (LSEC) is damaged by many toxins, including oxidants and bacterial toxins. Any effect on LSECs of the Pseudomonas aeruginosa virulence factor, pyocyanin, may be relevant for systemic pseudomonal infections and liver transplantation. In this study, the effects of pyocyanin on in vivo rat livers and isolated LSECs were assessed using electron microscopy, immunohistochemistry and biochemistry. In particular, the effect on fenestrations, a crucial morphological aspect of LSECs was assessed. Pyocyanin treatment induced a dose-dependent reduction in fenestrations in isolated LSECs. In the intact liver, intraportal injection of pyocyanin (11.9 ,M in blood) was associated with a reduction in endothelial porosity from 3.4 ± 0.2% (n = 5) to 1.3 ± 0.1% (n = 7) within 30 min. There were decreases in both diameter and frequency of fenestrations in the intact endothelium. There was also a decrease in endothelial thickness from 175.8 ± 5.8 to 156.5 ± 4.0 nm, an endothelial pathology finding previously unreported. Hepatocyte ultrastructure, liver function tests and immunohistochemical markers of oxidative stress (3-nitrotyrosine and malondialdehyde) were not affected. Pyocyanin induces significant ultrastructural changes in the LSEC in the absence of immunohistochemical evidence of oxidative stress or hepatocyte injury pointing to a novel mechanism for pyocyanin pathogenesis. [source] Neutropenia, thrombocytopenia and hepatic injury associated with dexketoprofen trometamol therapy in a previously healthy 35-year-old womanJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 1 2008S. Zabala MD Summary This case report describes a previously healthy 35-year-old woman, with an episode of fever, neutropenia, thrombocytopenia and elevation of biochemical markers of liver injury, 10 days after beginning drug therapy with dexketoprofen trometamol. Infectious and autoimmune causes of neutropenia, and viral or autoimmune hepatitis were excluded. The resolution following withdrawal of dexketoprofen trometamol confirms the possibility of an adverse drug reaction. [source] Vascular endothelial growth factor reduces Fas-mediated acute liver injury in miceJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7pt2 2008Yoichi Tanaka Abstract Background and Aim:, Fulminant hepatitis is still a fatal liver disease, and no specific treatment for it has been available. Vascular endothelial growth factor (VEGF) is the focus of attention because of its various actions. We investigated the effect of vascular endothelial growth factor (VEGF) on Fas-induced fulminant hepatic failure (FHF). Method:, Male Balb/c mice were treated with an intraperitoneal injection of an anti-Fas antibody (Jo-2 Ab) with or without premedication with intraperitoneally administered human recombinant VEGF. Results:, The serum level of alanine aminotransferase (ALT) was up to 300 times higher that of normal mice following the Jo-2 Ab injection, and histological analysis revealed hepatic injury and massive hepatocyte apoptosis. The VEGF significantly suppressed an elevation in serum ALT levels and hepatocyte apoptosis. Immunohistochemically, VEGF-treated mice showed that Bcl-xL in hepatocytes was strongly expressed. Conclusions:, Since hepatocytes do not express VEGF receptors, we speculated that VEGF acts on sinusoidal endothelial cells (SECs) and promotes production of cytokines such as hepatocyte growth factor in SECs, resulting in reducing apoptosis through an increase expression of Bcl-xL in hepatocytes. We suggest that VEGF has a potent antiapoptotic effect on hepatocytes through cell,cell interaction between SECs and hepatocytes. [source] Long-term administration of Salvia miltiorrhiza ameliorates carbon tetrachloride-induced hepatic fibrosis in ratsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2003Tzung-Yan Lee ABSTRACT Carbon tetrachloride (CCl4) is metabolized by cytochrome P450 to form a reactive trichloromethyl radical that triggers a chain of lipid peroxidation. These changes lead to cell injury, and chronic liver injury leads to excessive deposition of collagen in liver, resulting in liver fibrosis. The aim of this study was to evaluate the effects of long-term Salvia miltiorrhiza administration in CCl4 -induced hepatic injury in rats. Salvia miltiorrhiza (10, 25 or 50 mg kg,1 twice a day) was given for 9 weeks, beginning at the same time as the injections of CCl4. Rats receiving CCl4 alone showed a decreased hepatic glutathione level and an increased glutathione-S-transferase content. The hepatic thiobarbituratic acid-reactive substance levels were increased. CCl4 also caused a prominent collagen deposition in liver histology that was further supported by the increased hepatic mRNA expression of transforming growth factor-,1, tissue inhibitor of metallproteinase-1 and procollagen I. Salvia miltiorrhiza administration led to a dose-dependent increase in hepatic glutathione levels and a decrease in peroxidation products. Additionally, it reduced the mRNA expression of markers for hepatic fibrogenesis. In conclusion, long-term administration of Salvia miltiorrhiza in rats ameliorated the CCl4 -induced hepatic injury that probably related to a reduced oxidant stress and degree of hepatic fibrosis. [source] Anti-Inflammatory and Anti-Apoptotic Roles of Endothelial Cell STAT3 in Alcoholic Liver InjuryALCOHOLISM, Issue 4 2010Andrew M. Miller Background:, It is generally believed that the hepatoprotective effect of interleukin-6 (IL-6) is mediated via activation of signal transducer and activator of transcription 3 (STAT3) in hepatocytes. IL-6-deficient mice are more susceptible to alcohol-induced hepatocyte apoptosis and steatosis and elevation of serum alanine transaminase (ALT); however, whereas hepatocyte-specific STAT3 knockout mice are more susceptible to alcohol-induced hepatic steatosis, they have similar hepatocyte apoptosis and serum ALT after alcohol feeding compared with wild-type mice. This suggests that the hepatoprotective effect of IL-6 in alcoholic liver injury may be mediated via activation of STAT3-independent signals in hepatocytes, activation of STAT3 in nonparenchymal cells, or both. We have previously shown that IL-6 also activates STAT3 in sinusoidal endothelial cells (SECs). Thus, the purpose of this study was to investigate whether STAT3 in endothelial cells also plays a protective role in alcoholic liver injury. Methods:, Wild-type and endothelial cell-specific STAT3 knockout (STAT3E,/,) mice were pair-fed and fed ethanol containing diet for 4 weeks. Liver injury and inflammation were determined. Results:, Feeding mice with ethanol-containing diet for 4 weeks induced greater hepatic injury (elevation of serum ALT) and liver weight in STAT3E,/, mice than wild-type control groups. In addition, ethanol-fed STAT3E,/, mice displayed greater hepatic inflammation and substantially elevated serum and hepatic levels of IL-6 and TNF-, compared with wild-type mice. Furthermore, ethanol-fed STAT3E,/, mice displayed a greater abundance of apoptotic SECs and higher levels of serum hyaluronic acid than wild-type controls. Conclusions:, These data suggest that endothelial cell STAT3 plays important dual functions of attenuating hepatic inflammation and SEC death during alcoholic liver injury. [source] Protective effect of melatonin against oxidative stress induced by ligature of extra-hepatic biliary duct in rats: comparison with the effect of S-adenosyl- l -methionineJOURNAL OF PINEAL RESEARCH, Issue 3 2000Pedro Montilla López In the present research, we studied the effect of the administration of melatonin or S-adenosyl- l -methionine (S-AMe) on oxidative stress and hepatic cholestasis produced by double ligature of the extra-hepatic biliary duct (LBD) in adult male Wistar rats. Hepatic oxidative stress was evaluated by the changes in the amount of lipid peroxides and by the reduced glutathione content (GSH) in lysates of erythrocytes and homogenates of hepatic tissue. The severity of the cholestasis and hepatic injury were determined by the changes in the plasma enzyme activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AP), g-glutamyl-transpeptidase (GGT), and levels of albumin, total bilirubin (TB) and direct bilirubin (DB). Either melatonin or S-AMe were administered daily 3 days before LBD, and for 10 days after biliary obstruction. LDB caused highly significant increases in plasma enzyme activities and in bilirubin and lipid peroxides levels in erythrocytes and hepatic tissue. At the same time, this procedure produced a notable decrease in the GSH pools in these biological media. Both melatonin and S-AMe administration were effective as antioxidants and hepatoprotective substances, although the protective effects of melatonin were superior; it prevented the GSH decrease and reduced significantly the increases in enzyme activities and lipid peroxidation products produced by biliary ligature. S-AMe did not modify the increased GGT activity nor did it decrease greatly the TB levels (43% melatonin vs. 14% S-AMe). However, S-AMe was effective in preventing the loss of GSH in erythrocytes and hepatic tissue, as was melatonin. The obtained data permit the following conclusions. First, the LDB models cause marked hepatic oxidative stress. Second, the participation of free radicals of oxygen in the pathogenecity and severity of cholestasis produced by the acute obstruction of the extra-hepatic biliary duct is likely. Third, the results confirm the function of S-AMe as an antioxidant and hepatoprotector. Finally, melatonin is far more potent and provides superior protection as compared to S-AMe. Considering the decrease in oxidative stress and the intensity of cholestasis, these findings have interesting clinical implications for melatonin as a possible therapeutic agent in biliary cholestasis and parenchymatous liver injury. [source] Sirtinol attenuates hepatic injury and pro-inflammatory cytokine production following trauma-hemorrhage in male Sprague,Dawley ratsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2008F.-C. LIU Background: Although studies have demonstrated that sirtinol administration following adverse circulatory conditions is known to be protective, the mechanism by which sirtinol produces the salutary effects remains unknown. We hypothesized that sirtinol administration in male rats following trauma-hemorrhage decreases cytokine production and protects against hepatic injury. Methods: Male Sprague,Dawley rats underwent trauma-hemorrhage (mean blood pressure 40 mmHg for 90 min, then resuscitation). A single dose of sirtinol (1 mg/kg of body weight) or vehicle was administered intravenously during resuscitation. Twenty-four hours thereafter, tissue myeloperoxidase (MPO) activity (a marker of neutrophil sequestration), cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-3, intercellular adhesion molecule (ICAM)-1, and interleukin (IL)-6 levels in the liver and plasma alanine aminotransferase (ALT) concentrations were measured (n=6 Sprague,Dawley rats/group). Results: Trauma-hemorrhage increased hepatic MPO activity, CINC-1, CINC-3, ICAM-1, and IL-6 levels and plasma ALT concentrations. These parameters were significantly improved in the sirtinol-treated rats subjected to trauma-hemorrhage. Conclusion: The salutary effects of sirtinol administration on attenuation of hepatic injury following trauma-hemorrhage are, at least in part, related to reduction of pro-inflammatory mediators. [source] Screening, Diagnosis, and Monitoring of Hepatic InjuryJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 10 2003ANP-C, FAANP, Mary Jo Goolsby EdD Although prophylactic vaccines and a better screened blood supply have contributed to a decreased incidence of viral hepatitis, liver injury remains a common problem. It is important that nurse practitioners know which patients are at risk for hepatic injury, when and how to screen for hepatic injury, and how to monitor patients diagnosed with hepatic damage. The National Academy of Clinical Biochemistry guidelines related to hepatic injury provide a framework for the screening, diagnosis, and monitoring of hepatic injury resulting from a variety of causes. [source] | ||||||||||||||||||||||||||||||||||