Silent information regulator sirtuin 1 ameliorates acute liver failure via the p53/glutathione peroxidase 4/gasdermin D axis

BACKGROUND Acute liver failure(ALF)has a high mortality with widespread hepatocyte death involving ferroptosis and pyroptosis.The silent information regulator sirtuin 1(SIRT1)-mediated deacetylation affects multiple biological processes,including cellular senescence,apoptosis,sugar and lipid metabolism,oxidative stress,and inflammation.AIM To investigate the association between ferroptosis and pyroptosis and the upstream regulatory mechanisms.METHODS This study included 30 patients with ALF and 30 healthy individuals who underwent serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)testing.C57BL/6 mice were also intraperitoneally pretreated with SIRT1,p53,or glutathione peroxidase 4(GPX4)inducers and inhibitors and injected with lipopolysaccharide(LPS)/D-galactosamine(D-GalN)to induce ALF.Gasdermin D(GSDMD)^(-/-)mice were used as an experimental group.Histological changes in liver tissue were monitored by hematoxylin and eosin staining.ALT,AST,glutathione,reactive oxygen species,and iron levels were measured using commercial kits.Ferroptosis-and pyroptosis-related protein and mRNA expression was detected by western blot and quantitative real-time polymerase chain reaction.SIRT1,p53,and GSDMD were assessed by immunofluorescence analysis.RESULTS Serum AST and ALT levels were elevated in patients with ALF.SIRT1,solute carrier family 7a member 11(SLC7A11),and GPX4 protein expression was decreased and acetylated p5,p53,GSDMD,and acyl-CoA synthetase long-chain family member 4(ACSL4)protein levels were elevated in human ALF liver tissue.In the p53 and ferroptosis inhibitor-treated and GSDMD^(-/-)groups,serum interleukin(IL)-1β,tumour necrosis factor alpha,IL-6,IL-2 and C-C motif ligand 2 levels were decreased and hepatic impairment was mitigated.In mice with GSDMD knockout,p53 was reduced,GPX4 was increased,and ferroptotic events(depletion of SLC7A11,elevation of ACSL4,and iron accumulation)were detected.In vitro,knockdown of p53 and overexpression of GPX4 reduced AST and ALT levels,the cytostatic rate,and GSDMD expression,restoring SLC7A11 depletion.Moreover,SIRT1 agonist and overexpression of SIRT1 alleviated acute liver injury and decreased iron deposition compared with results in the model group,accompanied by reduced p53,GSDMD,and ACSL4,and increased SLC7A11 and GPX4.Inactivation of SIRT1 exacerbated ferroptotic and pyroptotic cell death and aggravated liver injury in LPS/D-GalNinduced in vitro and in vivo models.CONCLUSION SIRT1 activation attenuates LPS/D-GalN-induced ferroptosis and pyroptosis by inhibiting the p53/GPX4/GSDMD signaling pathway in ALF.

AGK2 pre-treatment protects against thioacetamide-induced acute liver failure via regulating the MFN2-PERK axis and ferroptosis signaling pathway

Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ failure.Methods:Animals were divided into 3 groups,normal,thioacetamide(TAA,ALF model)and TAA+AGK2.Cultured L02 cells were divided into 5 groups,normal,TAA,TAA+mitofusin 2(MFN2)-siRNA,TAA+AGK2,and TAA+AGK2+MFN2-siRNA groups.The liver histology was evaluated with hematoxylin and eosin staining,inositol-requiring enzyme 1(IRE1),activating transcription factor 6β(ATF6β),protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)and phosphorylated-PERK(p-PERK).C/EBP homologous protein(CHOP),reactive oxygen species(ROS),MFN2 and glutathione peroxidase 4(GPX4)were measured with Western blotting,and cell viability and liver chemistry were also measured.Mitochondriaassociated endoplasmic reticulum membranes(MAMs)were measured by immunofluorescence.Results:The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis,which were reduced by AGK2 pre-treatment.In comparison to the normal group,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+in the TAA-induced ALF model group were significantly increased,which were decreased by AGK2 pre-treatment.The levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group,which were enhanced by AGK2 pretreatment.Compared with the TAA-induced L02 cell,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA group.AGK2 pre-treatment decreased the apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 cell.Immunofluorescence observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced group in both mice and L02 cells.Conclusions:The data suggested that AGK2 pre-treatment had hepatoprotective role in TAA-induced ALF via upregulating the expression of MFN2 and then inhibiting PERK and ferroptosis pathway in ALF.

Understanding the molecular crossroads in acute liver failure:A pathway to new therapies

In this editorial we comment on the article published in a recent issue of the World Journal of Gastroenterology.Acute liver failure(ALF)is a critical condition characterized by rapid hepatocellular injury and organ dysfunction,and it often necessitates liver transplant to ensure patient survival.Recent research has eluci-dated the involvement of distinct cell death pathways,namely ferroptosis and pyroptosis,in the pathogenesis of ALF.Ferroptosis is driven by iron-dependent lipid peroxidation,whereas pyroptosis is an inflammatory form of cell death;both pathways contribute to hepatocyte death and exacerbate tissue damage.This comprehensive review explores the interplay between ferroptosis and pyroptosis in ALF,highlighting the role of key regulators such as silent information regulator sirtuin 1.Insights from clinical and preclinical studies provide valuable perspectives on the dysregulation of cell death pathways in ALF and the therapeutic potential of targeting these pathways.Collaboration across multiple disciplines is essential for translating the experimental insights into effective treatments for this life-threatening condition.

Viral etiologies of acute liver failure

Acute liver failure(ALF)is a rare cause of liver-related mortality worldwide,with an estimated annual global incidence of more than one million cases.While drug-induced liver injury,including acetaminophen toxicity,is the leading cause of ALF in the Western world,viral infections remain a significant cause of ALF and the most common cause in many developing nations.Given the high mortality rates associated with ALF,healthcare providers should be aware of the broad range of viral infections that have been implicated to enable early diagnosis,rapid treatment initiation when possible,and optimal management,which may include liver transplantation.This review aims to provide a summary of viral causes of ALF,diagnostic approaches,treatment options,and expected outcomes.

Targeting both ferroptosis and pyroptosis may represent potential therapies for acute liver failure

In this editorial,we comment on the article published in the recent issue of the World Journal of Gastroenterology.Acute liver failure(ALF)is a fatal disease that causes uncontrolled massive hepatocyte death and rapid loss of liver function.Ferroptosis and pyroptosis,cell death forms that can be initiated or blocked concurrently,can play significant roles in developing inflammation and various malignancies.However,their roles in ALF remain unclear.The article discovered the positive feedback between ferroptosis and pyroptosis in the progression of ALF,and revealed that the silent information regulator sirtuin 1(SIRT1)inhibits both pathways through p53,dramatically reducing inflammation and protecting hepatocytes.This suggests the potential use of SIRT1 and its downstream molecules as therapeutics for ALF.Thus,we will discuss the role of ferroptosis and pyroptosis in ALF and the crosstalk between these cell death mechanisms.Additionally,we address potential treatments that could alleviate ALF by simultaneously inhibiting both cell death pathways,as well as examples of SIRT1 activators being used as disease treatment strategies,providing new insights into the therapy of ALF.

Sirtuin 1 in regulating the p53/glutathione peroxidase 4/gasdermin D axis in acute liver failure

In this editorial,we comment on the article by Zhou et al.The study reveals the connection between ferroptosis and pyroptosis and the effect of silent information regulator sirtuin 1(SIRT1)activation in acute liver failure(ALF).ALF is characterized by a sudden and severe liver injury resulting in significant hepatocyte damage,often posing a high risk of mortality.The predominant form of hepatic cell death in ALF involves apoptosis,ferroptosis,autophagy,pyroptosis,and necroptosis.Glutathione peroxidase 4(GPX4)inhibition sensitizes the cell to ferroptosis and triggers cell death,while Gasdermin D(GSDMD)is a mediator of pyroptosis.The study showed that ferroptosis and pyroptosis in ALF are regulated by blocking the p53/GPX4/GSDMD pathway,bridging the gap between the two processes.The inhibition of p53 elevates the levels of GPX4,reducing the levels of inflammatory and liver injury markers,ferroptotic events,and GSDMDN protein levels.Reduced p53 expression and increased GPX4 on deletion of GSDMD indicated ferroptosis and pyroptosis interaction.SIRT1 is a NAD-dependent deacetylase,and its activation attenuates liver injury and inflammation,accompanied by reduced ferroptosis and pyroptosis-related proteins in ALF.SIRT1 activation also inhibits the p53/GPX4/GSDMD axis by inducing p53 acetylation,attenuating LPS/D-GalN-induced ALF.

Overview of ferroptosis and pyroptosis in acute liver failure

In this editorial,we comment on the article by Zhou et al published in a recent issue.We specifically focus on the crucial roles of ferroptosis and pyroptosis in acute liver failure(ALF),a disease with high mortality rates.Ferroptosis is the result of increased intracellular reactive oxygen species due to iron accumulation,glutathione(GSH)depletion,and decreased GSH peroxidase 4 activity,while pyroptosis is a procedural cell death mediated by gasdermin D which initiates a sustained inflammatory process.In this review,we describe the characteristics of ferroptosis and pyroptosis,and discuss the involvement of the two cell death modes in the onset and development of ALF.Furthermore,we summarize several interfering methods from the perspective of ferroptosis and pyroptosis for the alleviation of ALF.These observations might provide new targets and a theoretical basis for the treatment of ALF,which are also crucial for improving the prognosis of patients with ALF.

Novel insights into autophagy in gastrointestinal pathologies,mechanisms in metabolic dysfunction-associated fatty liver disease and acute liver failure

In this editorial,we comment on three articles published in a recent issue of World Journal of Gastroenterology.There is a pressing need for new research on autophagy's role in gastrointestinal(GI)disorders,and also novel insights into some liver conditions,such as metabolic dysfunction-associated fatty liver disease(MAFLD)and acute liver failure(ALF).Despite advancements,understanding autophagy's intricate mechanisms and implications in these diseases remains incomplete.Moreover,MAFLD's pathogenesis,encompassing hepatic steatosis and metabolic dysregulation,require further elucidation.Similarly,the mechanisms underlying ALF,a severe hepatic dysfunction,are poorly understood.Innovative studies exploring the interplay between autophagy and GI disorders,as well as defined mechanisms of MAFLD and ALF,are crucial for identifying therapeutic targets and enhancing diagnostic and treatment strategies to mitigate the global burden of these diseases.

Acute liver failure:A clinically severe syndrome characterized by intricate mechanisms

Acute liver failure presents as a clinical syndrome characterized by swift deterioration and significant mortality rates.Its underlying mechanisms are intricate,involving intricate interplays between various cells.Given the current scarcity of treatment options,there's a pressing need to diligently uncover the disease's core mechanisms and administer targeted therapies accordingly.

Pylephlebitis-induced acute liver failure: A case report and review of literature

BACKGROUND Pylephlebitis is an extremely rare form of septic thrombophlebitis involving the portal vein,carrying high rates of morbidity and mortality.CASE SUMMARY We present a case of a 42-year-old male with no past medical history who presented with acute onset of abdominal pain and altered mental status with laboratory tests demonstrating new-onset acute liver failure.Pylephlebitis was determined to be the underlying etiology due to subsequent workup revealing polymicrobial gram-negative anaerobic bacteremia and complete thrombosis of the main and left portal veins.To our knowledge,this is the first documented case of acute liver failure as a potential life-threatening complication of pylephlebitis.CONCLUSION Our case highlights the importance of considering pylephlebitis in the broad differential for abdominal pain,especially if there are co-existing risk factors for hypercoagulability.We also demonstrate that fulminant hepatic failure in these patients can potentially be reversible with the immediate initiation of antibiotics and anticoagulation.

Construction of a predictive model for acute liver failure after hepatectomy based on neutrophil-to-lymphocyte ratio and albuminbilirubin score

BACKGROUND Acute liver failure(ALF)is a common cause of postoperative death in patients with hepatocellular carcinoma(HCC)and is a serious threat to patient safety.The neutrophil-to-lymphocyte ratio(NLR)is a common inflammatory indicator that is associated with the prognosis of various diseases,and the albumin-bilirubin score(ALBI)is used to evaluate liver function in liver cancer patients.Therefore,this study aimed to construct a predictive model for postoperative ALF in HCC tumor integrity resection(R0)based on the NLR and ALBI,providing a basis for clinicians to choose appropriate treatment plans.AIM To construct an ALF prediction model after R0 surgery for HCC based on NLR and ALBI.METHODS In total,194 patients with HCC who visited The First People’s Hospital of Lianyungang to receive R0 between May 2018 and May 2023 were enrolled and divided into the ALF and non-ALF groups.We compared differences in the NLR and ALBI between the two groups.The risk factors of ALF after R0 surgery for HCC were screened in the univariate analysis.Independent risk factors were analyzed by multifactorial logistic regression.We then constructed a prediction model of ALF after R0 surgery for HCC.A receiver operating characteristic curve,calibration curve,and decision curve analysis(DCA)were used to evaluate the value of the prediction model.RESULTS Among 194 patients with HCC who met the standard inclusion criteria,46 cases of ALF occurred after R0(23.71%).There were significant differences in the NLR and ALBI between the two groups(P<0.05).The univariate analysis showed that alpha-fetoprotein(AFP)and blood loss volume(BLV)were significantly higher in the ALF group compared with the non-ALF group(P<0.05).The multifactorial analysis showed that NLR,ALBI,AFP,and BLV were independent risk factors for ALF after R0 surgery in HCC.The predictive efficacy of NLR,ALBI,AFP,and BLV in predicting the occurrence of ALT after R0 surgery for HCC was average[area under the curve(AUC)NLR=0.767,AUCALBI=0.755,AUCAFP=0.599,AUCBLV=0.718].The prediction model for ALF after R0 surgery for HCC based on NLR and ALBI had a better predictive efficacy(AUC=0.916).The calibration curve and actual curve were in good agreement.DCA showed a high net gain and that the model was safer compared to the curve in the extreme case over a wide range of thresholds.CONCLUSION The prediction model based on NLR and ALBI can effectively predict the risk of developing ALF after HCC R0 surgery,providing a basis for clinical prevention of developing ALF after HCC R0 surgery.

Dengue induced acute liver failure:A meta summary of case reports

BACKGROUND Dengue fever is the most common cause of viral hemorrhagic fever,with more than 400 million cases being reported annually,worldwide.Even though hepatic involvement is common,acute liver failure(ALF)is a rare complication of dengue fever.AIM To analyze the demographic profile,symptomology,hospital course and outcomes of patients presenting with ALF secondary to dengue infection by reviewing the published case reports.METHODS A systematic search was performed from multiple databases including PubMed,Reference Citation Analysis,Science Direct,and Google Scholar.The search terms used were"dengue"OR"severe dengue"OR"dengue shock syndrome"OR"dengue haemorrhagic syndrome"OR"dengue fever"AND"acute liver failure"OR"hepatic failure"OR"liver injury".The inclusion criteria were:(1)Case reports or case series with individual patient details;(2)Reported acute liver failure secondary to dengue infection;and(3)Published in English language and on adult humans.The data were extracted for patient demographics,clinical sympto-matology,clinical interventions,hospital and intensive care unit course,need for organ support and clinical outcomes.RESULTS Data from 19 case reports fulfilling the predefined inclusion criteria were included.The median age of patients was 38 years(inter quartile range:Q3-Q126.5 years)with a female preponderance(52.6%).The median days from diagnosis of dengue to development of ALF was 4.5 d.The increase in aspartate aminotransferase was higher than that in alanine aminotransferase(median 4625 U/L vs 3100 U/L).All the patients had one or more organ failure,with neurological failure present in 73.7%cases.42.1%patients required vasopressor support and hepatic enceph-alopathy was the most reported complication in 13(68.4%)cases.Most of the patients were managed conser-vatively and 2 patients were taken up for liver transplantation.Only 1 death was reported(5.3%).CONCLUSION Dengue infection may rarely lead to ALF.These patients may frequently require intensive care and organ support.Even though most of these patients may improve with supportive care,liver transplantation may be a therapeutic option in refractory cases.

Indocyanine green clearance test combined with MELD score in predicting the short-term prognosis of patients with acute liver failure

BACKGROUND: Acute liver failure(ALF) is an acute severe deterioration of liver function with high mortality. Early and accurate prognostic assessment of patients with ALF is critically important. Although the model for end-stage liver disease(MELD) scores and King’s College Hospital(KCH) criteria are well-accepted as predictive tools, their accuracy is unsatisfactory.The indocyanine green(ICG) clearance test(ICGR15, ICG retention rate at the 15 minutes) is a sensitive indicator of liver function. In this study, we investigated the efficacy of the ICGR15 for the short-term prognosis in patients with ALF. We compared the predictive value of ICGR15 with the MELD scores and KCH criteria.METHODS: Sixty-nine patients who had been diagnosed with ALF were recruited retrospectively. ICGR15 had been performed by ICG pulse spectrophotometry and relevant clinical and laboratory indices were analyzed within 24 hours of diagnosis.In addition, the MELD scores and KCH criteria were calculated.RESULTS: The three-month mortality of all patients was 47.83%.Age, serum total bilirubin and creatinine concentrations,international normalized ratio for prothrombin time, ICGR15,MELD scores and KCH criteria differed significantly between surviving and deceased patients. A positive correlation was observed between ICGR15 and MELD scores(r=0.328, P=0.006).The ICGR15-MELD model, Logit(P)=0.096×ICGR15+0.174 ×MELD score–9.346, was constructed by logistic regression analysis. The area under the receiver operating characteristic curve was 0.855. When set the cut-off point to-0.4684, the sensitivity was 87.90% and specificity, 72.20%. The area under the receiver operating characteristic curve of the ICGR15-MELD model(0.855) was significantly higher than that of the ICGR15(0.793), MELD scores(0.776) and KCH criteria(0.659).Based on this cut-off value, the patients were divided into two groups. The mortality was 74.36% in the first group(ICGR15-MELD≥-0.4686) and 13.33% in the second group(ICGR15-MELD<-0.4686), with a significant difference between the two groups(χ2=25.307, P=0.000).CONCLUSION: The ICGR15-MELD model is superior to the ICGR15, MELD scores, and KCH criteria in predicting the shortterm prognosis of patients with ALF.

Diagnostic criteria for acute liver failure due to Wilson disease

AIM： To describe the diagnostic criteria for acute liver failure due to Wilson disease （WD）, which is an uncommon cause of acute liver failure （ALF）. METHODS： We compared findings of patients presenting with ALF due to WD to those with ALF of other etiologies. RESULTS： Previously described criteria, such as low alkaline phosphatase activity, ratio of low alkaline phosphatase to total bilirubin or ratio of high aspartate arninotransferase （AST） to alanine arninotransferase （ALT）, failed to identify patients with ALF due to WD. There were significant differences in low ALT and AST activities （53 ± 43 vs 1982 ± 938, P 〈 0.0001 and 87 ± 44 vs 2756 ± 2941, P = 0.037, respectively）, low choline esterase activity （1.79 ± 1.2 vs 4.30 ± 1.2, P = 0.009）, high urine copper concentrations （93.4 ± 144.0 vs 3.5 ± 1.8, P = 0.001） and low hemoglobin （7.0 ± 2.2 vs 12.6 ± 1.8, P 〈 0.0001） in patients with ALF caused by WD as compared with other etiologies. Interestingly, 4 of 7 patients with ALF due to WD survived without liver transplantation. CONCLUSION： In ALF, these criteria can help establish a diagnosis of WD. Where applicable, slitlamp examination for presence of Kayser-Fleischer rings and liver biopsy for determination of hepatic copper concentration still remain important for the diagnosis of ALF due to WD. The need for liver transplantation should be evaluated carefully as the prognosis is not necessarily fatal.

Prognostic models for acute liver failure

BACKGROUND: Acute liver failure (ALF) remains a dramatic and unpredictable disease with high morbidity and mortality. Early and accurate prognostic assessment of patients with ALF is critically important for optimum clinical pathway. DATA SOURCES: Five English-language medical databases, MEDLINE, Science Direct, OVID, Springer Link and Wiley Interscience were searched for articles on 'acute liver failure', 'prognosis', and related topics. RESULTS: Multi-variable prognostic models including the King's College Hospital criteria and the model for end-stage liver disease score have been widely used in determination of the prognosis of ALF, but the results are far from satisfactory. Other prognostic indicators including serum Gc-globulin, arterial blood lactate, serum phosphate, arterial blood ammonia, and serum alpha-fetoprotein are promising but await further assessement. CONCLUSIONS: A reliable prognostic model to be developed in the future should not only have predictive value for poor outcome but also help to predict the survival of patients without a liver transplantation. Further studies are necessary to assess the prognostic accuracy of any new models. (Hepatobiliary Pancreat Dis Int 2010; 9: 122-128)

Role of monocytes and macrophages in experimental and human acute liver failure

Acute liver failure (ALF) is a devastating clinical syndrome characterised by progressive encephalopathy, coagulopathy, and circulatory dysfunction, which commonly leads to multiorgan failure and death. Central to the pathogenesis of ALF is activation of the immune system with mobilisation of cellular effectors and massive production of cytokines. As key components of the innate immune system, monocytes and macrophages are postulated to play a central role in the initiation, progression and resolution of ALF. ALF in humans follows a rapidly progressive clinical course that poses inherent difficulties in delineating the role of these pivotal immune cells. Therefore, a number of experimental models have been used to study the pathogenesis of ALF. Here we consider the evidence from experimental and human studies of ALF on the role of monocytes and macrophages in acute hepatic injury and the ensuing extrahepatic manifestations, including functional monocyte deactivation and multiple organ failure.

Dynamic tracking of stem cells in an acute liver failure model

AIM： To investigate a dual labeling technique, which would enable real-time monitoring of transplanted em- bryonic stem cell （ESC） kinetics, as well as long-term tracking. METHODS： Liver damage was induced in C57/BL6 male mice （n = 40） by acetaminophen （APAP） 300 mg/kg administered intraperitoneally. Green fluores- cence protein （GFP） positive C57/BL6 mouse ESCs were stained with the near-infrared fluorescent lipophilic tracer 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbo- cyanine iodide （DiR） immediately before transplantationinto the spleen. Each of the animals in the cell therapy group （n = 20） received 5 x 106 ESCs 4 h following treatment with APAP. The control group （n = 20） re- ceived the vehicle only. The distribution and dynamics of the cells were monitored in real-time with the IVIS lumina-2 at 30 rain post transplantation, then at 3, 12, 24, 48 and 72 h, and after one and 2 wk. Immunohisto- chemical examination of liver tissue was used to identify expression of GFP and albumin. Plasma alanine amino- transferase （ALT） was measured as an indication of liver damage.RESULTS： DiR-stained ESCs were easily tracked with the IVIS using the indocyanine green filter due to its high background passband with minimal background autofluorescence. The transplanted cells were confined inside the spleen at 30 min post-transplantation, gradu- ally moved into the splenic vein, and were detectable in parts of the liver at the 3 h time-point. Within 24 h of transplantation, homing of almost 90% of cells was confirmed in the liver. On day three, however, the DiR signal started to fade out, and ex vivo IVIS imaging of different organs allowed signal detection at time-points when the signal could not be detected by in vivo imag- ing, and confirmed that the highest photon emission was in the liver （P 〈 0.0001）. At 2 wk, the DiRsignal was no longer detectable in vivo; however, immuno- histochemistry analysis of constitutively-expressed GFP was used to provide an insight into the distribution of the cells. GFP ＋ve cells were detected in tissue sections resembling hepatocytes and were dispersed throughout the hepatic parenchyma, with the presence of a larger number of GFP ＋ve cells incorporated within the sinu- soidal endothelial lining. Very faint albumin expression was detected in the transplanted GFP ＋re cells at 72 h; however at 2 wk, few cells that were positive for GFP were also strongly positive for albumin. There was a significant improvement in serum levels of ALT, albumin and bilirubin in both groups at 2 wk when compared with the 72 h time-point. In the cell therapy group, serum ALT was significantly （P = 0.016） lower and al- bumin （P = 0.009） was significantly higher when com- pared with the control group at the 2 wk time-point;however there was no difference in mortality between the two groups. CONCLUSION： Dual labeling is an easy to use and cheap method for longitudinal monitoring of distribu- tion, survival and engraftment of transplanted cells, and could be used for cell therapy models.

Stromal cell derived factor-1 enhances bone marrow mononuclear cell migration in mice with acute liver failure

AIM： To evaluate the number of bone marrow mononuclear cells （BMMC） that are migrated to the liver following transplantation of murine BMMC into mice with acute liver injury.METHODS： BMMC were isolated from the bone marrow of mice in a lymphocyte separation medium and then labeled with PKH26. The labeled cells were subsequently infused into the caudal veins of BALB/c mice with hepatic injury induced by carbon tetrachloride and 2-acetylaminofluorene. Mice in experimental group were treated with stromal cell-derived factor-1 （SDF-1） which was injected intraperitoneally after trans- plantation of BMMC. Mice in control group were injected intraperitoneally with 0.1 mL of saline （0.9% NaCl） after transplantation of BMMC. After 2 wk, migration of the cells in experimental group was studied by fluorescence microscopy. The expression of proliferating cell nuclear antigen and albumin was quantified with manual methods in both groups. The serum transaminase levels at different time points were compared between the two groups.RESULTS： The labeled ＂cells＂ were found in the portal region and central veins of hepatic Iobules. The PKH26labeled cells appeared at an average frequency of 108 ± 8/high power field in the experiment group and 65 ± 8/high power field in the control group （P 〈 0.05）. The total number of positive cells was 29 ± 7/high power field in the experimental group and 13 ± 2/high power field in the control group. The albumin expression level was also higher in the experimental group than in the control group （29 ± 7 vs 13 ± 2, P 〈 0.05）. The total number of crossing points was 156 ± 5/high power field in the experimental group and 53 ± 5/high power field in the control group （P 〈 0.05）. The serum alanine aminotransferase levels in experimental and control groups were measured at different time points （120 ± 40 vs 118.50 ± 1.75, P 〉 0.05; 80.60 ± 6.50 vs 101.08 ± 5.67, P 〈 0.05; 50.74 ± 5.38 vs 80.47 ± 4.62, P 〈 0.05; 30.54 ± 2.70 vs 60.72 ± 4.37, P 〈 0.05; 30.77 ± 5.36 vs 40.47 ± 6.50, P 〈 0.05）. At the same time, the serum aspartate aminotransferase levels were measured in experimental and control groups at different time points （122.55 ± 1.46 vs 120.70 ± 4.22, P 〉 0.05; 54.26 ± 6.50 vs 98.70 ± 8.20, P 〈 0.05; 39.47 ± 5.39 vs 78.34 ± 4.50, P 〈 0.05; 28.94 ±2.70 vs 56.44 ± 4.28, P 〈 0.05; 30.77 ± 5.45 vs 42.50 ± 6.28, P 〈 0.05）.CONCLUSION： SDF-1 can promote the migration of BMMC to the liver of mice with acute liver failure.

Hybrid bioartificial liver support in cynomolgus monkeys with D-galactosamine-induced acute liver failure

AIM: To evaluate a hybrid bioartificial liver support system (HBALSS) in cynomolgus monkeys with acute liver failure.

Acute liver failure in Chinese children:a multicenter investigation

BACKGROUND: Currently, no documentation is available regarding Chinese children with acute liver failure(ALF). This study was undertaken to investigate etiologies and outcomes of Chinese children with ALF.METHODS: We retrospectively enrolled 32 pediatric patients with ALF admitted in five hospitals in different areas of China from January 2007 to December 2012. The coagulation indices, serum creatinine, serum lactate dehydrogenase,blood ammonia and prothrombin activity were analyzed; the relationship between these indices and mortality was evaluated by multivariate analysis.RESULTS: The most common causes of Chinese children with ALF were indeterminate etiology(15/32), drug toxicity(8/32),and acute cytomegalovirus hepatitis(6/32). Only 1 patient(3.13%)received liver transplantation and the spontaneous mortality of Chinese children with ALF was 58.06%(18/31). Patients who eventually died had higher baseline levels of international normalized ratio(P=0.01), serum creatinine(P=0.04), serum lactate dehydrogenase(P=0.01), blood ammonia(P<0.01) and lower prothrombin activity(P=0.01) than those who survived.Multivariate analysis showed that the entry blood ammonia was the only independent factor significantly associated with mortality(odds ratio=1.069, 95% confidence interval 1.023-1.117,P<0.01) and it had a sensitivity of 94.74%, a specificity of 84.62%and an accuracy of 90.63% for predicting the death. Based on the established model, with an increase of blood ammonia level,the risk of mortality would increase by 6.9%.CONCLUSIONS: The indeterminate causes predominated in the etiologies of ALF in Chinese children. The spontaneous mortality of pediatric patients with ALF was high, whereas the proportion of patients undergoing liver transplantation was significantly low. Entry blood ammonia was a reliable predictor for the death of pediatric patients with ALF.