Progression Of Acute Liver Failure Research Articles

Berberine attenuates ECM accumulation and the progression of acute liver failure through inhibition of NLRP3 inflammasome signalling

Acute liver failure (ALF) is a life-threatening disease, characterized by upregulated extracellular matrix deposition and inflammatory signalling, with no effective treatment options and targets. The present study was designed to investigate the preventive and therapeutic effects of berberine (BBR) and its underlying mechanism in thioacetamide (TAA)-induced ALF. Male SD rats were administered with TAA 300 mg/kg, i.p., thrice to induce ALF and pre- or post-treated with BBR. To decipher the effects of BBR LFT markers, histopathological analysis of key fibrotic and inflammatory proteins was performed. In addition, the levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α were assessed by ELISA. Our work showed TAA-induced ALF animals were associated with increased ALT, AST, bilirubin (LFT markers) and histopathological alterations with profuse infiltration of inflammatory cells in the liver tissue. Treatment with BBR has significantly inhibited LFT markers and histological alterations triggered by TAA. In addition, TAA animals demonstrated increased collagen accumulation and upregulated expression of TGF-β1, vimentin, and α-SMA compared to control. The excessive accumulation of collagen, TGF-β1, vimentin, and α-SMA were significantly modulated with BBR treatment. Further, the fluorescence intensity of ROS an activator of NLRP3 including the NLRP3 inflammasome, and its downstream signalling ASC, cleaved IL-1β, and other pro-inflammatory cytokines like TNF-α and IL-6 stimulated by TAA were attenuated by BBR treatment. The current work indicated that BBR significantly ameliorated TAA-induced ALF by inhibiting the extracellular matrix accumulation associated with the NLRP3/IL-1β signalling pathway and could be a viable therapeutic option to treat ALF and other fibroinflammatory diseases.

Comprehensive analysis of brain injury parameters in a preclinical porcine model of acute liver failure.

Acute liver failure (ALF) is defined as acute loss of liver function leading to hepatic encephalopathy associated with a high risk of patient death. Brain injury markers in serum and tissue can help detect and monitor ALF-associated brain injury. This study compares different brain injury parameters in plasma and tissue along with the progression of ALF. ALF was induced by performing an 85% liver resection. Following the resection, animals were recovered and monitored for up to 48 h or until reaching the predefined endpoint of receiving standard medical therapy (SMT). Blood and serum samples were taken at Tbaseline, T24, and upon reaching the endpoint (Tend). Control animals were euthanized by exsanguination following plasma sampling. Postmortem brain tissue samples were collected from the frontal cortex (FCTx) and cerebellum (Cb) of all animals. Glial fibrillary acidic protein (GFAP) and tau protein and mRNA levels were quantified using ELISA and qRT-PCR in all plasma and brain samples. Plasma neurofilament light (NFL) was also measured using ELISA. All ALF animals (n = 4) were euthanized upon showing signs of brain herniation. Evaluation of brain injury biomarkers revealed that GFAP was elevated in ALF animals at T24h and Tend, while Tau and NFL concentrations were unchanged. Moreover, plasma glial fibrillary acidic protein (GFAP) levels were negatively correlated with total protein and positively correlated with both aspartate transaminase (AST) and alkaline phosphatase (AP). Additionally, lower GFAP and tau RNA expressions were observed in the FCTx of the ALF group but not in the CB tissue. The current large animal study has identified a strong correlation between GFAP concentration in the blood and markers of ALF. Additionally, the protein and gene expression analyses in the FCTx revealed that this area appears to be susceptible, while the CB is protected from the detrimental impacts of ALF-associated brain swelling. These results warrant further studies to investigate the mechanisms behind this process.

MiRNA‑21 promotes the progression of acute liver failure via the KLF6/autophagy/IL‑23 signaling pathway.

Acute liver failure (ALF) is a complex syndrome characterized by overactivation of innate immunity, and the recruitment and differentiation of immune cells at inflammatory sites. The present study aimed to explore the role of microRNA (miRNA/miR)‑21 and its potential mechanisms underlying inflammatory responses in ALF. Baseline serum miR‑21 was analyzed in patients with ALF and healthy controls. In addition, miR‑21 antagomir was injected via the tail vein into C57BL/6 mice, and lipopolysaccharide/D‑galactosamine (LPS/GalN) was injected into mice after 48 h. The expression levels of miR‑21, Krüppel‑like‑factor‑6 (KLF6), autophagy‑related proteins and interleukin (IL)‑23, and hepatic pathology were then assessed in the liver tissue. Furthermore, THP‑1‑derived macrophages were transfected with a miRNA negative control, miR‑21 inhibitor, miR‑21 mimics or KLF6 overexpression plasmid, followed by treatment with or without rapamycin, and the expression levels of miR‑21, KLF6, autophagy‑related proteins and IL‑23 were evaluated. The results revealed that baseline serum miR‑21 levels were significantly upregulated in patients with ALF. In addition, LPS/GalN‑induced ALF was attenuated in the antagomir‑21 mouse group. KLF6 was identified as a target of miR‑21‑5p with one putative seed match site identified by TargetScan. A subsequent luciferase activity assay demonstrated a direct interaction between miR‑21‑5p and the 3'‑UTR of KLF6 mRNA. Further experiments suggested that miR‑21 promoted the expression of IL‑23 via inhibiting KLF6, which regulated autophagy. In conclusion, in the present study, baseline serum miR‑21 levels were highly upregulated in patients with ALF, antagomir‑21 attenuated LPS/GalN‑induced ALF in a mouse model, and miR‑21 could promote the expression of IL‑23 via inhibiting KLF6.

Treatment with β-Adrenoceptor Agonist Isoproterenol Reduces Non-parenchymal Cell Responses in LPS/D-GalN-Induced Liver Injury

There is an increasing evidence indicating the involvement of the sympathetic nervous system (SNS) in liver disease development. To achieve an extensive comprehension of the obscure process by which the SNS alleviates inflammatory damage in non-parenchymal liver cells (NPCs) during acute liver failure (ALF), we employ isoproterenol (ISO), a beta-adrenoceptor agonist, to mimic SNS signaling. ISO was administered to C57BL/6J mice to establish an acute liver failure (ALF) model using LPS/D-GalN, which was defined as ISO + ALF. Non-parenchymal cells (NPCs) were isolated from liver tissues and digested for tandem mass tag (TMT) labeled proteomics to identify differentially expressed proteins (DEPs). The administration of ISO resulted in a decreased serum levels of pro-inflammatory cytokines, e.g., TNF-α, IL-1β, and IL-6 in ALF mice, which alleviated liver damage. By using TMT analysis, it was possible to identify 1587 differentially expressed proteins (DEPs) in isolated NPCs. Notably, over 60% of the DEPs in the ISO + ALF vs. ALF comparison were shared in the Con vs. ALF comparison. According to enrichment analysis, the DEPs influenced by ISO in ALF mice were linked to biological functions of heme and fatty acid metabolism, interferon gamma response, TNFA signaling pathway, and mitochondrial oxidation function. Protein-protein interaction network analysis indicated Mapk14 and Caspase3 may serve as potentially valuable indicators of ISO intervention. In addition, the markers on activated macrophages, such as Mapk14, Casp1, Casp8, and Mrc1, were identified downregulated after ISO initiation. ISO treatment increased the abundance of anti-inflammatory markers in mouse macrophages, as evidenced by the immunohistochemistry (IHC) slides showing an increase in Arg + staining and a reduction in iNOS + staining. Furthermore, pretreatment with ISO also resulted in a reduction of LPS-stimulated inflammation signaling markers, Mapk14 and NF-κB, in human THP-1 cells. Prior treatment with ISO may have the potential to modify the biological functions of NPCs and could serve as an innovative pharmacotherapy for delaying the pathogenesis and progression of ALF.

Artificial cells delivering itaconic acid induce anti-inflammatory memory-like macrophages to reverse acute liver failure and prevent reinjury

Hepatic macrophages represent a key cellular component of the liver and are essential for the progression of acute liver failure (ALF). We construct artificial apoptotic cells loaded with itaconic acid (AI-Cells), wherein the compositions of the synthetic plasma membrane and surface topology are rationally engineered. AI-Cells are predominantly localized to the liver and further transport to hepatic macrophages. Intravenous administration of AI-Cells modulates macrophage inflammation to protect the liver from acetaminophen-induced ALF. Mechanistically, AI-Cells act on caspase-1 to suppress NLRP3 inflammasome-mediated cleavage of pro-IL-1β into its active form in macrophages. Notably, AI-Cells specifically induce anti-inflammatory memory-like hepatic macrophages in ALF mice, which prevent constitutive overproduction of IL-1β when liver reinjury occurs. In light of AI-Cells' precise delivery and training of memory-like hepatic macrophages, they offer promising therapeutic potential in reversing ALF by finely controlling inflammatory responses and orchestrating liver homeostasis, which potentially affect the treatment of various types of liver failure.

S2952 Cefepime-Induced Liver Injury

Introduction: Drug induced liver injury can be a result of many medications and remains as one of the most challenging disorders faced by GI specialists. The most common causes in the Western world include antimicrobials, antiepileptics, anticancer medications, herbal and dietary supplements. It is important to make the distinction between intrinsic and idiosyncratic types of DILI. Intrinsic DILI is capable of causing injury in a predictable pattern in humans when given in high doses. Idiosyncratic DILI only affects susceptible individuals and has less of an association to dosing. The latter being the more difficult type to diagnose and treat. An important value, the R-factor, is used to define hepatotoxicity injury patters. An R-factor < 2 suggests a cholestatic pattern, R-factor > 5 suggests a hepatocellular pattern, and in between a mixed pattern of injury. Early withdrawal of the offending agent is the treatment of choice for any cause of DILI as this prevents progression of acute liver failure. Case Description/Methods: We present a case of a 61 year old male (S, J) with acute elevations in his liver enzymes and alkaline phosphatase. Patient was admitted for alcohol withdrawal. The following day, patient was intubated secondary to hypercapnic respiratory failure and days later developed ventilator associated pneumonia for which he was started on antimicrobial therapy, cefepime and vancomycin. After 9 days of receiving cefepime, patient’s alkaline phosphatase and liver transaminases acutely increased. Patient’s baseline levels were normal on arrival to the hospital. His lab values were the following: ALT 263, AST 507, and alkaline phosphatase 279 with an R factor of 2.8 showing a mixed injury pattern. A right upper quadrant ultrasound showed hepatomegaly and an acute hepatitis panel was ordered which resulted negative. No episodes of significant hypotension were reported. The antibiotic was immediately discontinued with resolution of patient’s levels back to normal. Discussion: Though not as commonly reported, increased ALT, AST or alkaline phosphatase can be a result of cefepime use. Our patient on admission did not have abnormal liver chemistry tests despite his history of alcohol use. R-factor for our patient showed a mixed pattern of liver injury. First line tests when suspecting DILI such as acute viral hepatitis serologies and imaging studies were ordered. Our patient was not re-started on cefepime and his liver enzymes returned to baseline.

Identification of effective diagnostic biomarker and immune cell infiltration characteristics in acute liver failure by integrating bioinformatics analysis and machine-learning strategies

Background: To determine effective biomarkers for the diagnosis of acute liver failure (ALF) and explore the characteristics of the immune cell infiltration of ALF. Methods: We analyzed the differentially expressed genes (DEGs) between ALF and control samples in GSE38941, GSE62029, GSE96851, GSE120652, and merged datasets. Co-expressed DEGs (co-DEGs) identified from the five datasets were analyzed for enrichment analysis. We further constructed a PPI network of co-DEGs using the STRING database. Then, we integrated the two kinds of machine-learning strategies to identify diagnostic biomarkers of top hub genes screened based on MCC and Degree methods. And the potential diagnostic performance of the biomarkers for ALF was estimated using the AUC values. Data from GSE14668, GSE74000, and GSE96851 databases was performed as external verification sets to validate the expression level of potential diagnostic biomarkers. Furthermore, we analyzed the difference in the protein level of diagnostic biomarkers between normal and ALF mice models. Finally, we used CIBERSORT to estimate relative infiltration levels of 22 immune cell subsets in ALF samples and further analyzed the relationships between the diagnostic biomarkers and infiltrated immune cells. Results: A total of 200 co-DEGs were screened. Enrichment analyses depicted that they are highly enriched in metabolism and matrix collagen production-associated processes. The top 28 hub genes were obtained by integrating MCC and Degree methods. Then, the collagen type IV alpha 2 chain (COL4A2) was regarded as the diagnostic biomarker and showed excellent specificity and sensitivity. COL4A2 also showed a statistically significant difference and excellent diagnostic effectiveness in the verification set. In addition, there was a significant upregulation in the COL4A2 protein level in ALF mice models compared with the normal group. CIBERSORT analysis showed that activated CD4 T cells, plasma cells, macrophages, and monocytes may be implicated in the progress of ALF. In addition, COL4A2 showed different degrees of correlation with immune cells. Conclusion: In conclusion, COL4A2 may be a diagnostic biomarker for ALF, and immune cell infiltration may have important implications for the occurrence and progression of ALF.

Therapeutic potential of mesenchymal stem cells in the treatment of acute liver failure.

Acute liver failure (ALF) is a severe and life-threatening condition in which rapid deterioration of liver function develops in a patient who has no preexisting liver disease. Mesenchymal stem cells (MSCs) are immunoregulatory stem cells which are able to modulate phenotype and function of all immune cells that play pathogenic role in the development and progression of ALF. MSCs in juxtacrine and paracrine manner attenuate antigen-presenting properties of dendritic cells and macrophages, reduce production of inflammatory cytokines in T lymphocytes, suppress hepatotoxicity of natural killer T (NKT) cells and promote generation and expansion of immunosuppressive T, B and NKT regulatory cells in acutely inflamed liver. Due to their nano-sized dimension and lipid envelope, intravenously injected MSC-derived exosomes (MSC-Exos) may by-pass all biological barriers to deliver MSC-sourced immunoregulatoy factors directly into the liver-infiltrated immune cells and injured hepatocytes. Results obtained by us and others revealed that intravenous administration of MSCs and MSC-Exos efficiently attenuated detrimental immune response and acute inflammation in the liver, suggesting that MSCs and MSC-Exos could be considered as potentially new remedies in the immunotherapy of ALF. In this review, we emphasize the current knowledge about molecular and cellular mechanisms which are responsible for MSC-based modulation of liver-infiltrated immune cells and we discuss different insights regarding the therapeutic potential of MSCs in liver regeneration.

Targeting Thyroid Hormone/Thyroid Hormone Receptor Axis: An Attractive Therapy Strategy in Liver Diseases.

Thyroid hormone/thyroid hormone receptor (TH/TR) axis is characterized by TH with the assistance of plasma membrane transporters to combine with TR and mediate biological activities. Growing evidence suggests that TH/TR participates in plenty of hepatic metabolism. Thus, this review focuses on the role of the TH/TR axis in the liver diseases. To be specific, the TH/TR axis may improve metabolic-associated fatty liver disease, hepatitis, liver fibrosis, and liver injury while exacerbating the progression of acute liver failure and alcoholic liver disease. Also, the TH/TR axis has paradoxical roles in hepatocellular carcinoma. The TH/TR axis may be a prospecting target to cure hepatic diseases.

Hepatoprotective Effects of Albumin-Encapsulated Nanoparticles of a Curcumin Derivative COP-22 against Lipopolysaccharide/D-Galactosamine-Induced Acute Liver Injury in Mice.

Acute liver injury (ALI) is a severe syndrome and can further develop into acute liver failure (ALF) which can lead to high mortality and cause irreversible liver injuries in the clinic. Liver transplantation is the most common treatment; however, liver donors are lacking, and the progression of ALF is rapid. Nanoparticles can increase the bioavailability and the targeted accumulation of drugs in the liver, so as to significantly improve the therapeutic effect of ALI. Curcumin derivative COP-22 exhibits low cytotoxicity and effective anti-inflammatory activity; however, it has poor water solubility. In this study, COP-22-loaded bovine serum albumin (BSA) nanoparticles (22 NPs) were prepared and characterized. They exhibit effective hepatoprotective effects by inhibiting inflammation, oxidative stress, and apoptosis on Lipopolysaccharide/D-Galactosamine-induced acute liver injury of mice. The anti-inflammatory activity of 22 NPs is related to the regulation of the NF-κB signaling pathways; the antioxidant activity is related to the regulation of the Nrf2 signaling pathways; and the apoptosis activity is related to mitochondrial pathways, involving Bcl-2 family and Caspase-3 protein. These three cellular pathways are interrelated and affected each other. Moreover, 22 NPs could be passively targeted to accumulate in the liver through the retention effect and are more easily absorbed than 22.HCl salt in the liver.

Efficacy of N Acetyl Cysteine in Remdesvir Induced Hepatotoxicity in COVID-19 Patients

Background: Remdesvir has been approved as an emergency drug in SARS COVID infection. One of the side effects of remdesvir was found t be drug induced liver injury. There are case reports of progression to Acute Liver Failure in such patients. One of the treatments proposed is the withdrawal of the drug. N-acetyl Cysteine has been proposed in non acetaminophenan induced liver injury for the prevention of acute liver failure. The scope of N acetyl cysteine in remdesvir induced DILI has been investigated through this study. Aims: 1. Response to N Acetyl cysteine in patients with Remdesvir induced hepatotoxicity 2. Role of N Acetyl cysteine in progression of acute liver failure in DILI patients due to Remdesvir.3. Improvement of liver parameters after withdrawal of the drug in remdesvir induced liver injury patients.4.recovery from acute liver failure in NAC group. Methods: Patients without prior history of liver disease who develop DILI after giving remdesvir is divided into study and control group. The study population started on inj N Acetyl Cysteine 1g twice a day for 7 days and ALT was monitored on the 7th day. The complete LFT at the time of admission, day of intitation of NAC and day 7 was recorded. The results are compared. Results: NAC is potent in reducing serum ALT(control-76.4 ± 68.7 vs NAC- 50.4 ± 19.1, P<0.0001) and AST (control -67.2 ± 44.38 vs NAC-43.6 ± 13.8), P<0.0001)levels when compared to withdrawal group. No progression to acute liver failure was noted in both the groups. In patients with acute liver failure, the recovery was higher and more reduction in liver enzymes was noted when compared to control group. Conclusion: In our study, N- acetyl cysteine was found to be effective in Remdesvir induced hepatotoxicity and also found to be effective in recovery of acute liver failure.

VWF/ADAMTS13 Imbalance, But Not Global Coagulation or Fibrinolysis, Is Associated With Outcome and Bleeding in Acute Liver Failure.

Background and AimsRecent studies of acute liver failure (ALF) in man and animals have suggested that rebalanced hemostasis occurs, with distinct hypercoagulable features clinically evidenced by a low risk of bleeding. Rodent models have shown a link between intrahepatic microthrombus formation and progression of ALF. We sought to confirm these earlier findings in a large series of patients with well‐characterized ALF from the Acute Liver Failure Study Group.Approach and ResultsCitrated plasma samples taken on admission from 676 patients with ALF or acute liver injury (international normalized ratio ≥2.0 without hepatic encephalopathy) were used to determine levels of von Willebrand factor (VWF), a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activity, thrombomodulin‐modified thrombin generation, and clot lysis time (CLT) and compared with the levels in 40 healthy controls. Patients had 3‐fold increased VWF levels, 4‐fold decreased ADAMTS13 activity, similar thrombin generating capacity, and 2.4‐fold increased CLT, compared with controls. Increasing disease severity was associated with progressively more elevated VWF levels as well as hypofibrinolysis. Patients who died or underwent liver transplantation within 21 days of admission had higher VWF levels, lower ADAMTS13 activity, but similar thrombin generation and a similar proportion of patients with severe hypofibrinolysis, when compared with transplant‐free survivors. Likewise, patients with bleeding complications had higher VWF levels and lower ADAMTS13 activity compared to those without bleeding. Thrombin generation and CLT did not differ significantly between bleeding and nonbleeding patients.ConclusionsRebalanced hemostatic status was confirmed in a large cohort of patients with acute liver injury/ALF, demonstrating that VWF/ADAMTS13 imbalance is associated with poor outcome and bleeding. The association between VWF/ADAMTS13 imbalance and bleeding suggests that bleeding in ALF relates more to systemic inflammation than a primary coagulopathy.

Corallodiscus flabellata B. L. Burtt extract alleviates lipopolysaccharide/D-galactosamine-induced acute liver failure and brain injury by inhibiting oxidative stress, apoptosis, and inflammation.

Objective(s): Corallodiscus flabellata B. L. Burtt (CF) is distributed along liver meridian, with a possible beneficial effect in the progression of acute liver failure. Therefore, the present study investigates the effect of CF extract on rats with acute liver failure.Materials and Methods:Rats were divided into four experimental groups: Control, Lipopolysaccharide (LPS)/D-Galactosamine (D-GalN) (L/D), Wu Ling Powder + L/D (WLP+L/D) and CF + L/D. Animals were gavage for 7 days, after which all animals except the control group were injected intraperitoneally with LPS and D-GalN to induce acute liver failure. Subsequently, the urine was collected for the next 8 hr, and the liver pathological changes were observed. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), inflammatory factor and oxidative stress-related indicators were measured. The levels of reactive oxygen species (ROS), apoptosis marker in the liver, water content and aquaporin (AQPs) in the brain were detected. The concentration of ions and osmolality of urine and serum were determined.Results:The results show that CF significantly improved the damage of liver and brain tissue, and reversed the changes of serum ALT, AST, inflammatory factor and Cl-. It modulated oxidative stress-related indicators, reduced the content of ROS, apoptosis markers, water content, the level of Cl- ions and osmolality in the urine and the expression of AQP1, and AQP4 in the brain, and increased the urine output. Conclusion:It was found that the CF extract could alleviate the L/D induced acute liver failure by regulating the hepatocyte apoptosis and AQPs expression in the brain.

Role of the microRNA‑214/Bax axis in the progression of acute liver failure.

Acute liver failure (ALF) is a fatal liver disease characterized by severe hepatocyte destruction. MicroRNAs (miRNAs/miRs) have been reported to serve a key role in a number of liver diseases. Therefore, the aim of the present study was to investigate the role and underlying mechanism of miR-214 in ALF. ALF murine and hepatocyte models were established using D-galactosamine (D-GalN) and lipopolysaccharide (LPS) or D-GalN + tumor necrosis factor (TNF)-α, respectively. The expression levels of miR-214 and Bax were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and/or western blotting. Furthermore, an automatic biochemical analyzer was used to measure the levels of aspartate aminotransferase (AST) or alanine aminotransferase (ALT). The levels of TNF-α and interleukin (IL)-6 were detected by ELISA and RT-qPCR. In addition, TUNEL staining and flow cytometry were used to analyze cell apoptosis, and the protein expression of caspase-3 was determined by western blotting. It was identified that the levels of AST and ALT were increased and that hepatocyte apoptosis was enhanced in the D-GalN/LPS-stimulated group compared with the control. Furthermore, higher expression of caspase-3 was observed in the D-GalN/LPS-stimulated group. In addition, it was demonstrated that miR-214 was downregulated, while Bax was upregulated in D-GalN/LPS-stimulated mice and D-GalN/TNF-α-stimulated BNLCL2 cells. Moreover, in D-GalN/TNF-α-stimulated BNLCL2 cells, miR-214 overexpression suppressed apoptosis and decreased TNF-α and IL-6 levels, and these effects were reversed by the Bax plasmid. It was also identified that overexpression of miR-214 significantly decreased Bax mRNA and protein expression levels in vitro. Collectively, the present results suggested that miR-214 inhibited hepatocyte apoptosis during ALF development via targeting Bax, thus indicating that miR-214 may be a potential target for ALF treatment.

A Case of Multiple Antibiotic-Associated Hepatotoxicity in an Infant

Drug induced liver injury is one of the most frequent reasons for stopping treatment and the main cause of the onset and progression of acute liver failure, requiring liver transplantation. In children antibacterial drugs are on the first place in terms of hepatotoxicity, and the hepatocellular type is the most common type of liver damage. Often there is crosssensitivity within the same group of antibiotics, for example, beta-lactams. The aim: to analyze the causes of drug hepatotoxicity in the infant child while taking antibacterial agents. The article presents a clinical case of multiple hepatotoxicity caused by antibacterial agents such as beta-lactams, fluoroquinolones, sulfanilamides in one infant child, which suggests its genetic basis. It was shown that during therapy it is important to take into account the risk factors for hepatotoxicity (age, concomitant pathology, potential drug interactions with simultaneous use) and regularly evaluate the patient’s condition taking into account possible liver damage (including laboratory tests).

Suramin protects hepatocytes from LPS-induced apoptosis by regulating mitochondrial stress and inactivating the JNK-Mst1 signaling pathway.

An uncontrolled inflammatory response has been implicated in the progression of acute liver failure through poorly understood mechanisms. The aim of our study was to investigate whether suramin attenuates inflammation-mediated hepatocyte apoptosis by modulating mitochondrial homeostasis. Primary hepatocytes were isolated from mice and treated with LPS in vitro in the presence or absence of suramin. Western blotting, immunofluorescence staining, and ELISAs were used to evaluate the mitochondrial stress. The LPS treatment caused hepatocyte death via apoptosis. Interestingly, suramin supplementation attenuated LPS-mediated hepatocyte death by reducing Mst1 expression; the overexpression of Mst1 abolished the anti-apoptotic effects of suramin on LPS-treated hepatocytes. At the molecular level, suramin treatment repressed mitochondrial oxidative stress, sustained mitochondrial dynamics and blocked the caspase-9-mediated mitochondrial apoptosis pathway; these effects of suramin were achieved by reversing Mst1 expression. Furthermore, our study found that suramin modulated Mst1 expression via the JNK signaling pathway. Activation of JNK prevented the suramin-mediated Mst1 downregulation and concomitantly increased hepatocyte apoptosis and mitochondrial dysfunction. Taken together, our results confirmed the anti-apoptotic and anti-inflammatory effects of suramin on LPS-challenged hepatocytes. Suramin sustained hepatocyte viability and attenuated mitochondrial stress via repressing the JNK-Mst1 signaling pathway.

Transcriptome Analysis of Porcine PBMCs Reveals the Immune Cascade Response and Gene Ontology Terms Related to Cell Death and Fibrosis in the Progression of Liver Failure.

Background The key gene sets involved in the progression of acute liver failure (ALF), which has a high mortality rate, remain unclear. This study aims to gain a deeper understanding of the transcriptional response of peripheral blood mononuclear cells (PBMCs) following ALF. Methods ALF was induced by D-galactosamine (D-gal) in a porcine model. PBMCs were separated at time zero (baseline group), 36 h (failure group), and 60 h (dying group) after D-gal injection. Transcriptional profiling was performed using RNA sequencing and analysed using DAVID bioinformatics resources. Results Compared with the baseline group, 816 and 1,845 differentially expressed genes (DEGs) were identified in the failure and dying groups, respectively. A total of five and two gene ontology (GO) term clusters were enriched in 107 GO terms in the failure group and 154 GO terms in the dying group. These GO clusters were primarily immune-related, including genes regulating the inflammasome complex and toll-like receptor signalling pathways. Specifically, GO terms related to cell death, including apoptosis, pyroptosis, and autophagy, and those related to fibrosis, coagulation dysfunction, and hepatic encephalopathy were enriched. Seven Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, cytokine-cytokine receptor interaction, hematopoietic cell lineage, lysosome, rheumatoid arthritis, malaria, and phagosome and pertussis pathways were mapped for DEGs in the failure group. All of these seven KEGG pathways were involved in the 19 KEGG pathways mapped in the dying group. Conclusion We found that the dramatic PBMC transcriptome changes triggered by ALF progression was predominantly related to immune responses. The enriched GO terms related to cell death, fibrosis, and so on, as indicated by PBMC transcriptome analysis, seem to be useful in elucidating potential key gene sets in the progression of ALF. A better understanding of these gene sets might be of preventive or therapeutic interest.

Artificial liver support in pigs with acetaminophen-induced acute liver failure.

AIMTo establish a reversible porcine model of acute liver failure (ALF) and treat it with an artificial liver system.METHODSSixteen pigs weighing 30-35 kg were chosen and administered with acetaminophen (APAP) to induce ALF. ALF pigs were then randomly assigned to either an experimental group (n = 11), in which a treatment procedure was performed, or a control group (n = 5). Treatment was started 20 h after APAP administration and continued for 8 h. Clinical manifestations of all animals, including liver and kidney functions, serum biochemical parameters and survival times were analyzed.RESULTSTwenty hours after APAP administration, the levels of serum aspartate aminotransferase, total bilirubin, creatinine and ammonia were significantly increased, while albumin levels were decreased (P < 0.05). Prothrombin time was found to be extended with progression of ALF. After continuous treatment for 8 h (at 28 h), aspartate aminotransferase, total bilirubin, creatinine, and ammonia showed a decrease in comparison with the control group (P < 0.05). A cross-section of livers revealed signs of vacuolar degeneration, nuclear fragmentation and dissolution. Concerning survival, porcine models in the treatment group survived for longer times with artificial liver system treatment (P < 0.05).CONCLUSIONThis model is reproducible and allows for quantitative evaluation of new liver systems, such as a bioartificial liver. The artificial liver system (ZHJ-3) is safe and effective for the APAP-induced porcine ALF model.

Role of autophagy in acute liver failure induced by D-galactosamine/lipopolysaccharide in mice

Objective: To investigate the expression and role of autophagy in the progression of acute liver failure (ALF) using the mouse model of ALF induced by D-galactosamine/LPS (D-GalN/LPS). Methods: The C57BL/6 mice were used, and intraperitoneal injection of D-galactosamine (D-GalN) and lipopolysaccharide (LPS) was performed to establish the mouse model of ALF. The mice were divided into control group and 2-, 4-, and 6-hour D-GalN/LPS-induced ALF model groups. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured to assess liver function, and the pathological changes in liver tissue were observed to evaluate the status of liver injury. Quantitative real-time PCR was used to measure the expression of autophagy-related genes, Western blot was used to measure the expression of autophagy-related proteins in liver tissue, and a fluorescence microscope was used to observe the expression of autophagosome in the progression of liver failure. A one-way ANOVA was used for comparison of means of multiple samples between any two groups (LSD-t test for data with homogeneity of variance and Games-Howell method for data with heterogeneity of variance).P< 0.05 was considered statistically significant. Results: The ALF model groups showed gradual liver impairment over the time of D-GalN/LPS stimulation. There were significant increases in ALT and AST after 4 hours; the pathological injury of liver tissue gradually aggravated over the time of D-GalN/LPS stimulation and fulfilled the criteria for ALF at 6 hours. The mRNA and protein expression of autophagy-related genes (ATG-7, ATG-5, Beclin-1, Lamp-1, and LC3a) increased in the early and medium stages of ALF (2 and 4 hours) and decreased after ALF progressed to liver failure (6 hours). As was observed via the fluorescence microscope, the 4-hour D-GalN/LPS-induced ALF model group showed the highest expression of autophagosome. Conclusion: The expression of autophagy gradually increases in the early and medium stages of ALF and decreases when ALF progresses to liver failure. Therefore, autophagy plays an important role in the pathogenesis of ALF.

Role of endoplasmic reticulum stress in D-GalN/LPS-induced acute liver failure

To study the role of endoplasmic reticulum stress (ERS) in acute liver failure (ALF) using a mouse model of D-Galactosamine/lipopolysaccharide (D-GalN/LPS)-induced ALF. The ALF model was established by administering intraperitoneal (i.p.) injections of D-Ga1N (700 mg/kg) and LPS (10 mug/kg) to six C57BL/6 mice. Three of the modeled mice were also administered 4-phenylbutyrate (4-PBA; 100 mg/kg i.p.) at 6 hours before the onset of ALF and served as the intervention group. Non-modeled mice served as controls. All mice were analyzed by western blotting and qRT-PCR to determine the expression levels of ERS-related proteins in liver tissue. Liver function was assessed by measuring levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum. Extent of injury to the liver tissue was assessed by hematoxylin-eosin staining and histological analysis. qRT-PCR was also used to detect differences in expression of inflammation-related genes, and western blotting was also used to detect differences in expression of the apoptosis related protein Caspase-3.The extent of apoptosis in liver tissue was assessed by TUNEL assay. The ERS markers GRP78 and GRP94 showed increased expression at both the gene and protein levels which followed progression of ALF. The ERS effector proteins XBP-1, ATF-6 and IRE 1 a involved in the unfolded protein response were activated in the early stages of ALF, and the ERS-induced apoptosis regulators Caspase-12 and CHOP were activated in the late stage of ALF. Inhibition of ERS by 4-PBA intervention protected against injury to liver tissue and function, as evidenced by significantly lower levels of serum ALT and AST and a remarkably decreased extent of histological alterations. Furthermore, the inhibition of ERS suppressed expression of the proinflammatory cytokines TNFa, IL-6 and IL-1 β, and reduced the extent of hepatocyte apoptosis. ERS is activated in the mouse model of D-GalN/LPS-induced ALF. Inhibition of ERS may be protective against liver injury and the mechanism of action may involve reductions in inflammatory and apoptotic factors and/or signaling. Therefore, inhibiting ERS may represent a novel therapeutic approach for treating ALF.