Acute liver failure

Adverse Events and Outcomes of High-volume Plasma Exchange in 50 Acute Liver Failure Patients: A Monocentric Retrospective Real-world Study

Background and aims

Acute liver failure (ALF) is a condition that mostly requires Intensive Care Unit (ICU) admission and sometimes necessitates emergency liver transplantation. High-volume plasma exchange (HVPE) may improve transplant-free survival (TFS) in ALF. Our study assessed complications of HVPE therapy and outcome in ALF patients.

Methods

We conducted a single-center retrospective study of all patients admitted to the ICU for ALF and who underwent HVPE between June 2016 and June 2021. The plasmapheresis technique used was centrifugation, and the volume exchanged was calculated as 15% of the ideal body weight. Dedicated staff prospectively collected clinical adverse effects, while biological data were retrospectively collected. The primary outcome was the rate of severe adverse effects (SAE, defined as severe manifestations of hypotension, allergy, metabolic disturbances or other life-threatening event) that occurred during HVPE sessions. Factors influencing day-21 TFS were also studied.

Results

One hundred twenty sessions were performed in 50 patients. The main etiology for ALF was paracetamol (52% of the patients). During the session, hemoglobin, platelet, transaminases, ammonia and bilirubin decreased, coagulation factors increased, and creatinine and lactate remained unchanged. At least one SAE was reported for 32 out of 120 sessions (26.7% [19%-35.5%], mostly severe alkalosis [24/117], hypotension [4/120] and hypocalcemia [4/119]). Arterial pH ≤ 7.43 following HVPE and paracetamol etiology were negatively and positively associated with day-21 TFS, respectively.

Conclusion

Severe adverse effects were frequent during HVPE performed for ALF, mainly severe alkalosis, hypotension and hypocalcemia. Post-HVPE, pH and paracetamol etiology were prognosis markers.

Apocynin alleviates thioacetamide-induced acute liver injury: Role of NOX1/NOX4/NF-κB/NLRP3 pathways

The liver has a distinctive capacity to regenerate, yet severe acute injury can be life-threatening if not treated appropriately. Inflammation and oxidative stress are central processes implicated in the pathophysiology of acute livery injury. NOX isoforms are important enzymes for ROS generation, NF-κB and NLRP3 activation, its inhibition could be vital in alleviating acute liver injury (ALI). Here in our study, we used apocynin, a natural occurring potent NOX inhibitor, to exploreits potential protective effect against thioacetamide (TAA)-induced ALI through modulating crucial oxidative and inflammatory pathways. Rats were injected once with TAA (500 mg/kg/i.p) and treated with apocynin (10 mg/kg/i.p) twice before TAA challenge. Sera and hepatic tissues were collected for biochemical, mRNA expression, western blot analysis and histopathological assessments. Pretreatment with apocynin improved liver dysfunction evidenced by decreased levels of aminotransferases, ALP, GGT and bilirubin. Apocynin reduced mRNA expression of NOX1 and NOX4 which in turn alleviated oxidative stress, as shown by reduction in MDA and NOx levels, and elevation in GSH levels andcatalase and SOD activities. Moreover, apocynin significantly reduced MPO gene expression. We also demonstrate that apocynin ameliorated inflammation through activating IκBα and suppressing IKKα, IKKβ, NF-κBp65 and p-NF-κBp65, IL-6 andTNF-α. Additionally, apocynin potentiated the gene expression of anti-inflammatory IL-10 and reduced levels of hepatic NLRP3, Caspase-1 and IL-1β. These results suggest that apocynin protects against ALI in association with the inhibition of NOX1 and NOX4 and regulating oxidative and inflammatory pathways.

Bioactive compounds from dichloromethane extract of Artemisia rupestris L. alleviates CCl4/ConA-induced acute liver injury by inhibiting PI3K-AKT pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia rupestris L. (AR) is a traditional medicinal herb commonly used in the Uyghurs and Kazakhs; it was first documented in the Supplement to Compendium of Materia Medica written by Zhao Xuemin in the Qing Dynasty of China and is used clinically to treat colds, hepatitis, and allergic diseases.

AIM OF THE STUDY

The material basis and mechanisms of AR in acute liver injury (ALI) remain unclear. The purpose of this study was to reveal the possible active components involved in liver protection in AR and to preliminarily explore their pharmacological mechanisms.

MATERIALS AND METHODS

The chemical composition of the ethanolic extract (ARA) was identified by UPLC-Q-Exactive-MS/MS and confirmed by 32 reference standards. The pharmacodynamic results were utilized to screen the active part within the ARA that contribute to the amelioration of CCl4/ConA-induced ALI. The main active components and core targets were predicted by network pharmacology and verified by molecular docking combined with qPCR and Western blotting.

RESULTS

A total of 131 chemical components were identified in the ARA. The extraction parts of ARA had different therapeutic effects on ALI, among which the dichloromethane extract (ARA-D), which might constitute the main effective fraction of ARA, had significant anti-ALI effects. The network pharmacology results showed that targets including PIK3R1, AKT1, and EGFR, as well as 7 compounds, such as artemetin, vitexicarpin and rupestonic acid may play pivotal roles in treating CCl4/ConA-induced ALI. GO and KEGG pathway enrichment analyses revealed that the PI3K-AKT signaling pathway was the main pathway involved. In each model, ARA-D dose-dependently reduced the increase in ALT levels. High-dose ARA-D markedly decreased ALT activity from 196.79 ± 24.82 to 66.37 ± 16.19 U/L in the CCl4 model group and from 178.00 ± 28.39 to 50.67 ± 7.39 U/L in the ConA model group. Further studies revealed that ARA-D significantly inhibited TNF-α, IL-1β, and IL-6 expression and inhibited the protein expression of PI3K, p-PI3K, and p-AKT in CCl4/ConA-induced ALI.

CONCLUSION

ARA-D exhibits protective effects against ALI induced by CCl4/ConA, potentially through inhibition of the PI3K-AKT signaling pathway. These findings may help to determine the material basis and mechanisms of action of ARA-D for liver protection and provide ideas for future comprehensive studies.

Clinically relevant therapeutic approaches against acetaminophen hepatotoxicity and acute liver failure

Liver injury and acute liver failure caused by an acetaminophen (APAP) overdose is a significant clinical problem in western countries. With the introduction of the mouse model of APAP hepatotoxicity in the 1970 s, fundamental mechanisms of cell death were discovered. This included the recognition that part of the APAP dose is metabolized by cytochrome P450 generating a reactive metabolite that is detoxified by glutathione. After the partial depletion of glutathione, the reactive metabolite will covalently bind to sulfhydryl groups of proteins, which is the initiating event of the toxicity. This insight led to the introduction of N-acetyl-L-cysteine, a glutathione precursor, as antidote against APAP overdose in the clinic. Despite substantial progress in our understanding of the pathomechanisms over the last decades viable new antidotes only emerged recently. This review will discuss the background, mechanisms of action, and the clinical prospects of the existing FDA-approved antidote N-acetylcysteine, of several new drug candidates under clinical development [4-methylpyrazole (fomepizole), calmangafodipir] and examples of additional therapeutic targets (Nrf2 activators) and regeneration promoting agents (thrombopoietin mimetics, adenosine A2B receptor agonists, Wharton's Jelly mesenchymal stem cells). Although there are clear limitations of certain therapeutic approaches, there is reason to be optimistic. The substantial progress in the understanding of the pathophysiology of APAP hepatotoxicity led to the consideration of several drugs for development as clinical antidotes against APAP overdose in recent years. Based on the currently available information, it is likely that this will result in additional drugs that could be used as adjunct treatment for N-acetylcysteine.

Plasma exchange does not improve overall survival in patients with acute liver failure in a real world cohort

BACKGROUND AND AIMS

Therapeutic plasma exchange (PEX) has emerged as a potential treatment option for patients with acute liver failure (ALF). The effect of PEX on survival outcomes outside of clinical trials is not yet well established. In this study we aimed to evaluate the real-world use and outcomes of PEX for the treatment of ALF.

METHODS

This multicentre retrospective cohort study included consecutive patients with ALF admitted to all 7 tertiary liver transplant centres in the United Kingdom (UK) between June 2013 and December 2021. Changes in clinical variables following PEX treatment was assessed and overall survival and transplant free survival (TFS) to hospital discharge of patients receiving PEX were compared to those receiving standard medical therapy (SMT). Propensity score matching was performed to control for intergroup covariates and selection bias.

RESULTS

We included 378 patients with ALF (median (IQR) age 36 (28-48), 64% (n=242) female) of which 120 received PEX. There was a significant improvement in most clinical variables following PEX, including median dose of noradrenaline (reduction from 0.35 μg/kg/min (0.19 - 0.70 μg/kg/min) to 0.16 μg/kg/min (0.08 - 0.49) (p = 0.001). There was no significant difference between PEX and SMT groups in overall survival (51.4 % v 62.6 % respectively, p = 0.12) or TFS (42.6 % v 53.1 %, p = 0.24).

CONCLUSION

PEX is now frequently used in the management of ALF patients in the UK. It is associated with significant improvement in haemodynamic parameters but there is no survival benefit.

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.

Long-term expanded hepatic progenitor cells ameliorate D-GalN/LPS-induced acute liver failure through repolarizing M1 macrophage to M2-Like phenotype via activation of the IL-10/JAK2/STAT3 signaling pathway

Acute liver failure (ALF) is a devastating liver disease characterized by the rapid deterioration of hepatocytes, which causes a series of clinical complications, including hepatic dysfunction, coagulopathy, encephalopathy, and multiorgan failure. Cell-based therapy is a promising alternative as it can bridge patients until their livers regenerate, releasing immunomodulatory molecules to suppress inflammation. This study reports an iPSCs-derived long-term expanded hepatic progenitor cell (LTHepPCs), which can differentiate into hepatocyte-like cells (HLCs) in vivo. When introduced into drug-induced ALF models, LTHepPCs mitigate liver damage by modulating the local immune microenvironment. This is achieved by shifting macrophages/Kupffer cells towards an anti-inflammatory state, resulting in a decrease in the expression of inflammatory cytokines such as TNF-a, IL-1β, and IL-8, and an increase in the expression of anti-inflammatory cytokines such as IL-10 and ARG-1. In vitro co-culturing of THP-1 or mBMDMs with LTHepPCs suggested that LTHepPCs could activate the anti-inflammatory state of macrophages/Kupffer cells via the IL-10/JAK2/STAT3 signaling pathway. Therefore, LTHepPC transplantation is a promising therapy for ALF patients.

Impact of Renal Replacement Therapy on Outcomes of Living Donor Liver Transplantation for Acute Liver Failure: A Cohort Study

Despite the promising role of renal replacement therapy (RRT) in acute liver failure (ALF), high-risk patients need liver transplantation and remain at risk for death due to cerebral complications. The objective of this study was to report outcomes of living donor liver transplantation (LDLT) for ALF with perioperative RRT. This was a single-center retrospective cohort study. Out of 1167 LDLTs, 24 patients had ALF and met the King's College criteria for transplantation. They were categorized into no-RRT (n = 13) and RRT (n = 11) groups. We looked at 1-year posttransplant survival in these patients. The median serum ammonia level at the time of transplant in the no-RRT and RRT groups was 259.5 mcg/dL (222.7-398) and 70.6 mcg/dL (58.1-92.6) (p = 0.005). In the RRT group, serum ammonia level < 100 mcg/dL was achieved in all patients. Seven (53.8%) patients in the no-RRT group and 11/11 (100%) in the RRT group were extubated and regained full consciousness after LDLT (p = 0.013). The 90-day mortality was 6/13 (46.1%) and 2/11 (18.1%) (p = 0.211). There was no brainstem herniation-related mortality in the RRT group, that is, 5/13 (38.4%) and 0/11 (0%) (p = 0.030). The 1-year posttransplant survival was also significantly higher in the RRT group (p = 0.031). The use of RRT lowers serum ammonia levels and might reduce posttransplant mortality due to brainstem herniation.

Enzyme-responsive, multi-lock optical probes for molecular imaging and disease theranostics

Optical imaging is an indispensable tool for non-invasive visualization of biomolecules in living organisms, thereby offering a sensitive approach for disease diagnosis and image-guided disease treatment. Single-lock activatable optical probes (SOPs) that specifically switch on optical signals in the presence of biomarkers-of-interest have shown both higher detection sensitivity and imaging quality as compared to conventional "always-on" optical probes. However, such SOPs can still show "false-positive" results in disease diagnosis due to non-specific biomarker expression in healthy tissues. By contrast, multi-lock activatable optical probes (MOPs) that simultaneously detect multiple biomarkers-of-interest could improve detection specificity towards certain biomolecular events or pathological conditions. In this Review, we discuss the recent advancements of enzyme-responsive MOPs, with a focus on their biomedical applications. The higher detection specificity of MOPs could in turn enhance disease diagnosis accuracy and improve treatment efficacy in image-guided disease therapy with minimal toxicity in the surrounding healthy tissues. Finally, we discuss the current challenges and suggest future applications of MOPs.

Acute liver failure: A practical update

Acute liver failure is a rare and dynamic condition, with a broad aetiology and an incompletely understood pathophysiology. Management of this life-threatening disease requires critical care and organ support and frequently early liver transplantation. Proper identification, prevention and treatment of complications such as intracranial hypertension and sepsis are critical to optimising outcomes. The identification of the cause of acute liver failure and the prompt initiation of the aetiological treatment can also improve prognosis. Survival has progressively improved in parallel to advances in medical treatment. Intracranial hypertension complicating hepatic encephalopathy is less frequent than in the past and intracranial pressure monitoring now relies on non-invasive techniques. Current prognostic models have good accuracy to identify patients who will die without liver transplantation but are not able to identify those in whom transplantation is futile. New prognostic markers to select patients for transplantation are still in the pipeline. Therapeutic plasma exchange and, in some centers, early renal replacement therapy are well established treatments for the disease. The use of other artificial liver devices in clinical practice is not supported by evidence. This review is intended to provide a clinical update on the management of acute liver failure, incorporating the most recent advances in the field.

Insights gained into the injury mechanism of drug and herb induced liver injury in the hepatic microenvironment

Drug-Induced Liver Injury (DILI) and herb Induced Liver Injury (HILI) continues to pose a substantial challenge in both clinical practice and drug development, representing a grave threat to patient well-being. This comprehensive review introduces a novel perspective on DILI and HILI by thoroughly exploring the intricate microenvironment of the liver. The dynamic interplay among hepatocytes, sinusoidal endothelial cells, Kupffer cells, hepatic stellate cells, cholangiocytes, and the intricate vascular network assumes a central role in drug metabolism and detoxification. Significantly, this microenvironment is emerging as a critical determinant of susceptibility to DILI and HILI. The review delves into the multifaceted interactions within the liver microenvironment, providing valuable insights into the complex mechanisms that underlie DILI and HILI. Furthermore, we discuss potential strategies for mitigating drug-induced liver injury by targeting these influential factors, emphasizing their clinical relevance. By highlighting recent advances and future prospects, our aim is to shed light on the promising avenue of leveraging the liver microenvironment for the prevention and mitigation of DILI and HILI. This deeper understanding is crucial for advancing clinical practices and ensuring patient safety in the realm of DILI and HILI.

[Liver transplantation in acute and acute-on-chronic liver failure]

Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) are diseases with a rapidly progressive course and high mortality. Apart from treating the underlying triggers and intensive care measures, there are very limited therapeutic options for either condition. Liver transplantation is often the only life-saving treatment, but it cannot always be employed due to contraindications and severe disease progression. ACLF is characterized by underlying liver cirrhosis and typical triggers such as bacterial infections, bleeding, or alcohol binges. ALF occurs in previously healthy livers, usually as a result of purely hepatotoxic events. Disease differences are also reflected in the course and regulations of liver transplantation. Newer prognostic parameters and prioritization programs for ACLF can help improve both waiting list mortality and outcomes after transplantation.

Acute liver failure

Acute liver failure (ALF) is a life-threatening disorder characterised by rapid deterioration of liver function, coagulopathy, and hepatic encephalopathy in the absence of pre-existing liver disease. The cause of ALF varies across the world. Common causes of ALF in adults include drug toxicity, hepatotropic and non-hepatotropic viruses, herbal and dietary supplements, antituberculosis drugs, and autoimmune hepatitis. The cause of liver failure affects the management and prognosis, and therefore extensive investigation for cause is strongly suggested. Sepsis with multiorgan failure and cerebral oedema remain the leading causes of death in patients with ALF and early identification and appropriate management can alter the course of ALF. Liver transplantation is the best current therapy, although the role of artificial liver support systems, particularly therapeutic plasma exchange, can be useful for patients with ALF, especially in non-transplant centres. In this Seminar, we discuss the cause, prognostic models, and management of ALF.

Altered Mental Status in the Solid-Organ Transplant Recipient

Patients undergoing solid-organ transplantation (SOT) face a tumultuous journey. Prior to transplant, their medical course is characterized by organ dysfunction, diminished quality of life, and reliance on organ support, all of which are endured in hopes of reaching the haven of organ transplantation. Peritransplant altered mental status may indicate neurologic insults acquired during transplant and may have long-lasting consequences. Even years after transplant, these patients are at heightened risk for neurologic dysfunction from a myriad of metabolic, toxic, and infectious causes. This review provides a comprehensive examination of causes, diagnostic approaches, neuroimaging findings, and management strategies for altered mental status in SOT recipients. Given their complexity and the numerous etiologies for neurologic dysfunction, liver transplant patients are a chief focus in this review; however, we also review lesser-known contributors to neurological injury across various transplant types. From hepatic encephalopathy to cerebral edema, seizures, and infections, this review highlights the importance of recognizing and managing pre- and posttransplant neurological complications to optimize patient outcomes.

Efficacy of steroid therapy for improving native liver survival after pediatric acute liver failure with immune activation

AIM

Recent evidence suggests that acute liver failure (ALF) in some patients may reflect a dysregulated immune response, and that corticosteroids improve survival of the native liver in ALF patients with high serum alanine aminotransferase levels, which are an indication of liver inflammation. However, it is unclear whether steroids are effective for pediatric acute liver failure (PALF). The aim of this retrospective case-control study is to examine whether steroid therapy for PALF accompanied by immune activation improves the survival of native liver and to identify factors that predict responses to steroid treatment.

METHODS

Of 38 patients with PALF treated at Kyoto University Hospital from February 2006 to August 2022, 19 receiving steroids who met the specific criteria for identifying the pathophysiology of immune activity in the liver (the "Steroid group"), and seven steroid-free patients who also met the criteria ("Nonsteroid group") were enrolled. Patients in the "Steroid group" were categorized as "responders" or "nonresponders" according to treatment outcome. Clinical and histological data were analyzed.

RESULTS

Survival of the native liver in the Steroid group was significantly higher than that in the Nonsteroid group (68% vs. 0%, respectively; p = 0.0052). Nonresponders were significantly younger, with higher Model for End-stage Liver Disease and pediatric end-stage liver disease scores, higher prothrombin time - international normalized ratio, and higher serum ferritin levels than responders. Massive hepatic necrosis was more common in nonresponders.

CONCLUSION

Steroid therapy is effective for PALF patients with liver inflammation; however, liver transplantation should be prioritized for young children with ALF accompanied by severe coagulopathy or massive hepatic necrosis.

Macrophage activation markers are associated with infection and mortality in patients with acute liver failure

BACKGROUND AND AIMS

Acute liver failure is a multisystem disorder with a high mortality and frequent need for emergency liver transplantation. Following massive innate immune system activation, soluble markers of macrophage activation are released during liver damage and their association with disease severity and prognosis requires exploration.

METHODS

Patients ALF from the United States Acute Liver Failure Study Group (USALFSG, n = 224) and King's College Hospital (n = 40) together with healthy controls (HC, n = 50) were recruited. Serum from early (Days 1-3) and late (>Day 3) time points were analysed for MAMs by enzyme-linked immunosorbent assay correlated to markers of illness severity and 21-day spontaneous survival. Surface expression phenotyping was performed via Flow Cytometry on CD14+ monocytes.

RESULTS

All MAMs serum concentrations were significantly higher in ALF compared to controls (p < .0001). sCD206 concentration was higher in early and late stages of the disease in patients with bacteraemia (p = .002) and infection in general (p = .006). In MELD-adjusted multivariate modelling, sCD206 and sCD163 were independently associated with mortality. CD14+ monocyte expression of CD206 (p < .001) was higher in patients with ALF compared with controls and correlated with SOFA score (p = .018). sCD206 was independently validated as a predictor of infection in an external cohort.

CONCLUSIONS

sCD206 is increased in serum of ALF patients with infections and poor outcome and is upregulated on CD14+ monocytes. Later measurements of sCD163 and sCD206 during the evolution of ALF have potential as mechanistic predictors of mortality. sCD206 should be explored as a biomarker of sepsis and mortality in ALF.

1H NMR spectroscopic characterisation of HepG2 cells as a model metabolic system for toxicology studies

The immortalised human hepatocellular HepG2 cell line is commonly used for toxicology studies as an alternative to animal testing due to its characteristic liver-distinctive functions. However, little is known about the baseline metabolic changes within these cells upon toxin exposure. We have applied 1H Nuclear Magnetic Resonance (NMR) spectroscopy to characterise the biochemical composition of HepG2 cells at baseline and post-exposure to hydrogen peroxide (H2O2). Metabolic profiles of live cells, cell extracts, and their spent media supernatants were obtained using 1H high-resolution magic angle spinning (HR-MAS) NMR and 1H NMR spectroscopic techniques. Orthogonal partial least squares discriminant analysis (O-PLS-DA) was used to characterise the metabolites that differed between the baseline and H2O2 treated groups. The results showed that H2O2 caused alterations to 10 metabolites, including acetate, glutamate, lipids, phosphocholine, and creatine in the live cells; 25 metabolites, including acetate, alanine, adenosine diphosphate (ADP), aspartate, citrate, creatine, glucose, glutamine, glutathione, and lactate in the cell extracts, and 22 metabolites, including acetate, alanine, formate, glucose, pyruvate, phenylalanine, threonine, tryptophan, tyrosine, and valine in the cell supernatants. At least 10 biochemical pathways associated with these metabolites were disrupted upon toxin exposure, including those involved in energy, lipid, and amino acid metabolism. Our findings illustrate the ability of NMR-based metabolic profiling of immortalised human cells to detect metabolic effects on central metabolism due to toxin exposure. The established data sets will enable more subtle biochemical changes in the HepG2 model cell system to be identified in future toxicity testing.

Concanavalin-A-Induced Acute Liver Injury in Mice

Acute liver injury is a life-threatening disease. Although immune responses are involved in the development and exacerbation of acute liver injury, the cellular and molecular mechanisms are not fully understood. Intravenous administration of the plant lectin concanavalin A (ConA) is widely used as a model of acute liver injury. ConA triggers T cell activation and cytokine production by crosslinking glycoproteins, including the T cell receptor, leading to the infiltration of myeloid cells into the liver and the subsequent amplification of inflammation in the liver. Thus, the pathogenesis of ConA-induced acute liver injury is considered a model of immune-mediated acute liver injury or autoimmune hepatitis in humans. However, the severity of the liver injury and the analyses of immune cells and non-hematopoietic cells in the liver following ConA injection are significantly influenced by the experimental conditions. This article outlines protocols for ConA-induced acute liver injury in mice and evaluation methods for liver injury, immune cells, and non-hematopoietic cells in the liver. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Induction of acute liver injury by ConA injection Basic Protocol 2: Evaluation of inflammatory cytokines in mouse plasma Basic Protocol 3: Preparation of liver sections and histological analysis of liver injury Basic Protocol 4: Preparation of liver immune cells Basic Protocol 5: Preparation of hepatocytes, endothelial cells, and hepatic stellate cells Basic Protocol 6: Flow cytometry of immune and non-hematopoietic liver cells Basic Protocol 7: Flow cytometric sorting of endothelial cells and hepatic stellate cells Basic Protocol 8: Quantitative reverse transcription polymerase chain reaction.

Nutritional management for acute liver failure

Acute liver failure (ALF) induces increased energy expenditure and disrupts the metabolism of essential nutrients. Hepatic encephalopathy is a complication of ALF with a poor prognosis and mainly involves the metabolic disturbance of amino acids in its pathogenesis. In this review, we discuss the nutritional management for ALF in consideration of the pathophysiology of ALF with respect to the impairment of hepatocyte function. It is known that enteral nutrition is recommended for patients with ALF, while parenteral nutrition is recommended for patients who cannot tolerate enteral nutrition. As ALF leads to a hypermetabolic state, the energy intake is recommended to cover 1.3 times the resting energy expenditure. Because of the high risk of hypoglycemia associated with disturbances in glucose metabolism, substantial glucose intake is recommended. Along with the deterioration of glucose metabolism, protein metabolism is also disrupted. As patients with ALF have increased systemic protein catabolism together with decreased protein synthesis, appropriate amounts of amino acids or protein under monitoring serum ammonia levels are recommended. In conclusion, nutritional management based on the understanding of nutritional pathophysiology is a pivotal therapeutic approach for patients with ALF. The approach should be individualized in the acute phase, the recovery phase, and the pretransplant phase.

Incidence of acute liver failure and its associated mortality in patients with dengue infection: A systematic review and meta-analysis

Acute liver failure (ALF) is a devastating consequence of dengue infection. This systematic review and meta-analysis assessed the incidence of ALF in dengue infection and its associated mortality. We systematically searched the EMBASE and MEDLINE databases from inception to December 2023 for observational studies reporting ALF incidence and mortality in dengue patients. Twenty-one studies encompassing 26,839 dengue-infected patients were included. Meta-analysis revealed a pooled incidence of ALF in cases of general dengue infection of 2.0 % (95 % CI, 1.2-3.0 %), with 1.2 % (95 % CI, 0.6-2.1 %) in adults and 5.0 % (95 % CI, 1.5-10.2 %) in children. ALF incidence was 17.3 % (95 % CI, 6.5 %-31.5 %) in severe dengue and 7.4 % (95 % CI, 0.8-18.5 %) in dengue shock syndrome. The pooled mortality rate of dengue-associated ALF was 47.0 % (95 % CI, 32.9-61.2 %). These findings underscore the detrimental impact of dengue infection on the development of the relatively uncommon, albeit life-threatening, condition of ALF.

Cell competition in primary and metastatic colorectal cancer

Adult tissues set the scene for a continuous battle between cells, where a comparison of cellular fitness results in the elimination of weaker "loser" cells. This phenomenon, named cell competition, is beneficial for tissue integrity and homeostasis. In fact, cell competition plays a crucial role in tumor suppression, through elimination of early malignant cells, as part of Epithelial Defense Against Cancer. However, it is increasingly apparent that cell competition doubles as a tumor-promoting mechanism. The comparative nature of cell competition means that mutational background, proliferation rate and polarity all factor in to determine the outcome of these processes. In this review, we explore the intricate and context-dependent involvement of cell competition in homeostasis and regeneration, as well as during initiation and progression of primary and metastasized colorectal cancer. We provide a comprehensive overview of molecular and cellular mechanisms governing cell competition and its parallels with regeneration.

The cost implications of Wilson disease among hospitalized patients: analysis of USA hospitals

BACKGROUND AND AIM

In this study, we used a national cohort of patients with Wilson's disease (WD) to investigate the admissions, mortality rates, and costs over the captured period to assess specific subpopulations at higher burden.

METHODS

Patients with WD were selected using 2016-2019 National Inpatient Sample (NIS). The weighted estimates and patient data were stratified using demographics and medical characteristics. Regression curves were graphed to derive goodness-of-fit for each trend from which R2 and P values were calculated.

RESULTS

Annual total admissions per 100 000 hospitalizations due to WD were 1075, 1180, 1140, and 1330 ( R2  = 0.75; P  = 0.13) from 2016 to 2019. Within the demographics, there was an increase in admissions among patients greater than 65 years of age ( R2  = 0.90; P  = 0.05) and White patients ( R2  = 0.97; P  = 0.02). Assessing WD-related mortality rates, there was an increase in the mortality rate among those in the first quartile of income ( R2  = 1.00; P  < 0.001). The total cost for WD-related hospitalizations was $20.90, $27.23, $24.20, and $27.25 million US dollars for the years 2016, 2017, 2018, and 2019, respectively ( R2  = 0.47; P  = 0.32). There was an increasing total cost trend for Asian or Pacific Islander patients ( R2  = 0.90; P  = 0.05). Interestingly, patients with cirrhosis demonstrated a decreased trend in the total costs ( R2  = 0.97; P  = 0.02).

CONCLUSION

Our study demonstrated that certain ethnicity groups, income classes and comorbidities had increased admissions or costs among patients admitted with WD.

Review article: Hepatic steatosis and its associations with acute and chronic liver diseases

BACKGROUND

Hepatic steatosis is a common finding in liver histopathology and the hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), whose global prevalence is rising.

AIMS

To review the histopathology of hepatic steatosis and its mechanisms of development and to identify common and rare disease associations.

METHODS

We reviewed literature on the basic science of lipid droplet (LD) biology and clinical research on acute and chronic liver diseases associated with hepatic steatosis using the PubMed database.

RESULTS

A variety of genetic and environmental factors contribute to the development of chronic hepatic steatosis or steatotic liver disease, which typically appears macrovesicular. Microvesicular steatosis is associated with acute mitochondrial dysfunction and liver failure. Fat metabolic processes in hepatocytes whose dysregulation leads to the development of steatosis include secretion of lipoprotein particles, uptake of remnant lipoprotein particles or free fatty acids from blood, de novo lipogenesis, oxidation of fatty acids, lipolysis and lipophagy. Hepatic insulin resistance is a key feature of MASLD. Seipin is a polyfunctional protein that facilitates LD biogenesis. Assembly of hepatitis C virus takes place on LD surfaces. LDs make important, functional contact with the endoplasmic reticulum and other organelles.

CONCLUSIONS

Diverse liver pathologies are associated with hepatic steatosis, with MASLD being the most important contributor. The biogenesis and dynamics of LDs in hepatocytes are complex and warrant further investigation. Organellar interfaces permit co-regulation of lipid metabolism to match generation of potentially toxic lipid species with their LD depot storage.

Acute liver failure: Management update and prognosis

Acute liver failure is a rare but serious syndrome, with an incidence of approximately 2,000 to 3,000 cases per year in North America. Its pathophysiology and clinical course vary, depending on the cause of the primary liver injury, and can lead to high morbidity and mortality or the need for liver transplantation, despite available therapies. This syndrome involves excessive activation of the immune system, with damage in other organs, contributing to its high mortality rate. The most accepted definition includes liver injury with hepatic encephalopathy and coagulopathy within the past 26 weeks in a patient with no previous liver disease. The main causes are paracetamol poisoning, viral hepatitis, and drug-induced liver injury, among others. Identifying the cause is crucial, given that it influences prognosis and treatment. Survival has improved with supportive measures, intensive therapy, complication prevention, and the use of medications, such as N-acetylcysteine. Liver transplantation is a curative option for nonresponders to medical treatment, but adequate evaluation of transplantation timing is vital for improving results. Factors such as patient age, underlying cause, and severity of organ failure influence the post-transplant outcomes and survival.

Microcirculatory disturbance in acute liver injury is triggered by IFNγ-CD40 axis

BACKGROUND

Acute liver failure (ALF) is a life-threatening disorder that progresses from self-limiting acute liver injury (ALI). Microcirculatory disturbance characterized by sinusoidal hypercoagulation and subsequent massive hypoxic hepatocyte damage have been proposed to be the mechanism by which ALI deteriorates to ALF; however, the precise molecular pathway of the sinusoidal hypercoagulation remains unknown. Here, we analyzed ALI patients and mice models to uncover the pathogenesis of ALI with microcirculatory disturbance.

METHODS

We conducted a single-center retrospective study for ALI and blood samples and liver tissues were analyzed to evaluate the microcirculatory disturbance in ALI patients (n = 120). Single-cell RNA sequencing analysis (scRNA-seq) was applied to the liver from the concanavalin A (Con A)‑induced mouse model of ALI. Interferon-gamma (IFNγ) and tumor necrosis factor-alpha knockout mice, and primary human liver sinusoidal endothelial cells (LSECs) were used to assess the mechanism of microcirculatory disturbance.

RESULTS

The serum IFNγ concentrations were significantly higher in ALI patients with microcirculatory disturbance than in patients without microcirculatory disturbance, and the IFNγ was upregulated in the Con A mouse model which presented microcirculatory disturbance. Hepatic IFNγ expression was increased as early as 1 hour after Con A treatment prior to sinusoidal hypercoagulation and hypoxic liver damage. scRNA-seq revealed that IFNγ was upregulated in innate lymphoid cells and stimulated hepatic vascular endothelial cells at the early stage of liver injury. In IFNγ knockout mice treated with Con A, the sinusoidal hypercoagulation and liver damage were remarkably attenuated, concomitant with the complete inhibition of CD40 and tissue factor (TF) upregulation in vascular endothelial cells. By ligand-receptor analysis, CD40-CD40 ligand interaction was identified in vascular endothelial cells. In human LSECs, IFNγ upregulated CD40 expression and TF was further induced by increased CD40-CD40 ligand interaction. Consistent with these findings, hepatic CD40 expression was significantly elevated in human ALI patients with microcirculatory disturbance.

CONCLUSION

We identified the critical role of the IFNγ-CD40 axis as the molecular mechanism of microcirculatory disturbance in ALI. This finding may provide novel insights into the pathogenesis of ALI and potentially contribute to the emergence of new therapeutic strategies for ALI patients.

Assessing the clinical efficacy of low-volume therapeutic plasma exchange in achieving recovery from acute liver failure induced by yellow phosphorous poisoning

BACKGROUND

Acute liver failure (ALF) following yellow phosphorous (YP) ingestion is similar to acetaminophen-induced ALF and it has become a public concern in our region. This study assessed low volume therapeutic plasma exchange (LV-TPE) efficacy in improving the transplant free survival in YP poisoning.

METHODS

Adult patients with toxicology reports of YP and ALF requiring critical care were included in the study. LV-TPE was planned for three consecutive days and three more if required. Performed 1.3 to 1.5 plasma volume replacing with 0.9% normal saline, 5% human albumin solution, and fresh frozen plasma based on ASFA 2019 criteria. MELD score, laboratory parameters, LV-TPE details were captured. The study end point was clinical outcome of the patients.

RESULTS

Among 36 patients, 19 underwent LV-TPE and 17 opted out of LV-TPE and they were included as a control arm. The MELD score was 32.64 ± 8.05 and 37.83 ± 9.37 in both groups. There were 13 survivors in LV-TPE group leading to a 68.42% reduction in mortality. The coagulation and biochemical parameters showed a significant percentage change after LV-TPE. Refractory shock, delay in initiating procedure and acidosis were independent predictors of mortality.

CONCLUSION

A well-timed LV-TPE improves the survival of patients with ALF due to YP poisoning.

Liver transplantation for acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) occurs in the context of advanced liver disease and is associated with hepatic and extrahepatic organ failure, eventually leading to a major risk of short-term mortality. To date, there are very few effective therapeutic options for ACLF. In many cases, liver transplantation is the only life-saving treatment that has acceptable outcomes in carefully selected recipients. This Review addresses key aspects of the use of liver transplantation for patients with ACLF, providing an in-depth discussion of existing evidence regarding candidate selection, the optimal window for transplantation, potential prioritisation of liver grafts for this indication, and the global management of ACLF to bridge patients to liver transplantation.

Epstein Barr Virus-Related Acute Liver Failure and Hemophagocytosis in an Immunocompetent Individual: An Autopsy Report

Epstein-Barr virus (EBV) is a nonhepatotropic virus. It causes mild self-limiting illness characterized by fever, oral ulcer, diarrhea, lymphadenopathy, and hepatosplenomegaly. Rarely it causes acute liver failure (ALF). EBV-related ALF (EBV-ALF) accounts for 0.2% of all ALF cases. The prognosis of EBV-ALF is dismal, and it can affect both immunocompromised and immunocompetent individuals. We performed a partial autopsy on a 30-year-old immunocompetent individual with infectious mononucleosis and ALF. The autopsy showed characteristic histomorphology of EBV-ALF in the form of centrizonal confluent hepatocytic necrosis, portal mixed inflammatory infiltrate, sinusoidal lymphocytosis, numerous hemophagocytic figures, and tissue Epstein-Barr encoded RNA-in situ hybridization (EBER-ISH) positivity. Extensive hemophagocytosis was noted in the liver, spleen, lymph node, and bone marrow. Other features include T-zone expansion of lymph nodes and spleen, interstitial pneumonia pattern in the lungs, and exanthematous skin changes. EBV-DNA polymerase chain reaction from the postmortem blood sample yielded 70,200 copies/µL. The index case highlights the uncommon occurrence of EBV-ALF, its histomorphological features, and its putative pathogenesis.

Continuous renal replacement therapy and survival in acute liver failure: A systematic review and meta-analysis

OBJECTIVE

Acute liver failure (ALF) is a rare syndrome leading to significant morbidity and mortality. An important cause of mortality is cerebral edema due to hyperammonemia. Different therapies for hyperammonemia have been assessed including continuous renal replacement therapy (CRRT). We conducted a systematic review and meta-analysis to determine the efficacy of CRRT in ALF patients.

MATERIALS AND METHODS

We searched MEDLINE, EMBASE, Cochrane Library, and Web of Science. Inclusion criteria included adult patients admitted to an ICU with ALF. Intervention was the use of CRRT for one or more indications with the comparator being standard care without the use of CRRT. Outcomes of interest were overall survival, transplant-free survival (TFS), mortality and changes in serum ammonia levels.

RESULTS

In total, 305 patients underwent CRRT while 1137 patients did not receive CRRT. CRRT was associated with improved overall survival [risk ratio (RR) 0.83, 95% confidence interval (CI) 0.70-0.99, p-value 0.04, I2 = 50%] and improved TFS (RR 0.65, 95% CI 0.49-0.85, p-value 0.002, I2 = 25%). There was a trend towards higher mortality with no CRRT (RR 1.24, 95% CI 0.84-1.81, p-value 0.28, I2 = 37%). Ammonia clearance data was unable to be pooled and was not analyzable.

CONCLUSION

Use of CRRT in ALF patients is associated with improved overall and transplant-free survival compared to no CRRT.

Dihydroquercetin improves experimental acute liver failure by targeting ferroptosis and mitochondria-mediated apoptosis through the SIRT1/p53 axis

BACKGROUND

Ferroptosis and mitochondria-mediated apoptosis are both involved in the pathogenesis of acute liver failure (ALF). Ferroptosis-produced reactive oxygen species (ROS) trigger the chain oxidation of polyunsaturated phospholipids and promote mitochondrial apoptosis. Dihydroquercetin (DHQ) also plays an important protective role against liver injury.

PURPOSE

Here, we aimed to investigate the protective effects of DHQ on ALF. We also explored the underlying mechanism.

METHODS

We established a Lipopolysaccharide (LPS)/D-galactosamine (D-Gal)-induced ALF mouse model and tumor necrosis factor-α (TNF-α)/D-Gal-induced ALF LO2 cell model. 2',7'-Dichlorofluorescein diacetate (DCFH-DA) and Dihydroethidium (DHE) were used to detect total ROS levels. Lipid ROS was assessed using C11-BODIPY flow cytometry. Lipid peroxidative products levels were detected using MDA ELISA assay and 4-hydroxynonenal (4-HNE) immunohistochemistry. QRT-PCR and western blots were used to test mRNA and protein expression levels, respectively. Cell viability was evaluated with CCK8 assay, and apoptosis was analyzed using flow cytometry.

RESULTS

DHQ treatment improved LPS/D-Gal-induced ALF, as well as TNF-α/D-Gal-induced reductions in LO2 viability and increased sirtuin 1 (SIRT1) expression. DHQ pretreatment also reduced the accumulation of ROS, reduced lipid peroxidation, elevated mitochondrial membrane potentials (ΔΨm), and decreased liver cell apoptosis both in vivo and in vitro. Additionally, the knockdown of SIRT1 and p53 activator (Tenovin-6) treatment reversed DHQ's inhibitory effects on ferroptosis and mitochondria-mediated apoptosis in vitro. DHQ enhanced p53 deacetylation by both up-regulating SIRT1 expression and directly bonding to SIRT1. We also found that Tenovin-6's stimulatory effects on ferroptosis and mitochondria-mediated apoptosis in the DHQ-treated LO2 ALF cell model were partially attenuated by overexpression of solute carrier family 7member 11 (SLC7A11), as well as by apoptotic protease activating factor 1 (Apaf-1) knockdown.

CONCLUSION

Our results suggest that DHQ alleviated ALF by inhibiting both ferroptosis and mitochondria-mediated apoptosis by regulating the SIRT1/p53 axis. Thus, DHQ may serve as a novel therapy for ALF.

Role of high-volume plasmapheresis in the management of paediatric acute liver failure

OBJECTIVES

Paediatric acute liver failure (PALF) is a life-threatening disease. Management aims to support hepatic regeneration or to bridge to liver transplantation. High-volume plasmapheresis (HVP) removes protein-bound substances, alleviates inflammation, and improves survival in adult acute liver failure. However, experience with HVP in PALF is limited. Aim of this study is to report on feasibility, safety, efficacy and outcomes of HVP in PALF.

METHODS

Retrospective observational study in children with PALF. HVP was performed upon identification of negative prognostic indicators, in toxic aetiology or multiorgan failure (MOF). Exchanged volume with fresh-frozen plasma corresponded to 1.5-2.0 times the patient's estimated plasma volume. One daily cycle was performed until the patient met criteria for discontinuation, that is, liver regeneration, liver transplantation, or death.

RESULTS

Twenty-two children with PALF (body weight 2.5-106 kg) received 1-7 HVP cycles. No bleeding or procedure-related mortality occurred. Alkalosis, hypothermia and reduction in platelets were observed. Haemolysis led to HVP termination in one infant. Seven children (32%) survived with their native livers, 13 patients (59%) underwent liver transplantation. Two infants died due to MOF. Overall survival was 86%. International normalization ratio (INR), alanine aminotransaminases (ALT), bilirubin and inotropic support were reduced significantly (p < 0.05) after the first HVP-cycle (median): INR 2.85 versus 1.5; ALT 1280 versus 434 U/L; bilirubin 12.7 versus 6.7 mg/dL; norepinephrine dosage 0.083 versus 0.009 µg/kg/min. Median soluble-interleukin-2-receptor dropped significantly following HVP (n = 7): 2407 versus 950 U/mL (p < 0.02).

CONCLUSIONS

HVP in PALF is feasible, safe, improves markers of liver failure and inflammation and is associated with lowering inotropic support. Prospective and controlled studies are required to confirm efficacy of HVP in PALF.

Multimodal decoding of human liver regeneration

The liver has a unique ability to regenerate1,2; however, in the setting of acute liver failure (ALF), this regenerative capacity is often overwhelmed, leaving emergency liver transplantation as the only curative option3-5. Here, to advance understanding of human liver regeneration, we use paired single-nucleus RNA sequencing combined with spatial profiling of healthy and ALF explant human livers to generate a single-cell, pan-lineage atlas of human liver regeneration. We uncover a novel ANXA2+ migratory hepatocyte subpopulation, which emerges during human liver regeneration, and a corollary subpopulation in a mouse model of acetaminophen (APAP)-induced liver regeneration. Interrogation of necrotic wound closure and hepatocyte proliferation across multiple timepoints following APAP-induced liver injury in mice demonstrates that wound closure precedes hepatocyte proliferation. Four-dimensional intravital imaging of APAP-induced mouse liver injury identifies motile hepatocytes at the edge of the necrotic area, enabling collective migration of the hepatocyte sheet to effect wound closure. Depletion of hepatocyte ANXA2 reduces hepatocyte growth factor-induced human and mouse hepatocyte migration in vitro, and abrogates necrotic wound closure following APAP-induced mouse liver injury. Together, our work dissects unanticipated aspects of liver regeneration, demonstrating an uncoupling of wound closure and hepatocyte proliferation and uncovering a novel migratory hepatocyte subpopulation that mediates wound closure following liver injury. Therapies designed to promote rapid reconstitution of normal hepatic microarchitecture and reparation of the gut-liver barrier may advance new areas of therapeutic discovery in regenerative medicine.

Glucagon-like Peptide-1 Receptor Agonist Use in Patients With Liver Cirrhosis and Type 2 Diabetes

BACKGROUND AND AIMS

Liver cirrhosis is often associated with type 2 diabetes (T2D), but research on treatment of T2D in cirrhotic patients is scarce. We investigated the long-term outcomes of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in patients with T2D and cirrhosis.

METHODS

Using propensity score matching, we selected 467 matched pairs of GLP-1 RA users and nonusers from the National Health Insurance Research Database of Taiwan from January 1, 2008, to December 31, 2019. Multivariable-adjusted Cox proportional hazards models were used to compare the outcomes between GLP-1 RA users and nonusers.

RESULTS

The mean follow-up time was 3.28 and 3.06 years for GLP-1 RA users and nonusers, respectively. The rates of death were 27.46 and 55.90 per 1000 person-years for GLP-1 RA users and nonusers, respectively. The multivariable-adjusted models showed that GLP-1 RA users had lower risks of mortality (adjusted hazard ratio [aHR], 0.47; 95% confidence interval [CI], 0.32-0.69), cardiovascular events (aHR, 0.6; 95% CI, 0.41-0.87), decompensated cirrhosis (aHR, 0.7; 95% CI, 0.49-0.99), hepatic encephalopathy (aHR, 0.59; 95% CI, 0.36-0.97), and liver failure (aHR, 0.54; 95% CI, 0.34-0.85) than nonusers. A longer cumulative duration of GLP-1 RA use had a lower risk of these outcomes than GLP-1 RA nonuse.

CONCLUSIONS

This population-based cohort study showed that GLP-1 RA users exhibited a significantly lower risk of death, cardiovascular events, decompensated cirrhosis, hepatic encephalopathy, and liver failure in patients with T2D and compensated liver cirrhosis. Additional studies are needed to confirm our results.

Application of TSPO-Specific Positron Emission Tomography Radiotracer as an Early Indicator of Acute Liver Failure Induced by Propacetamol, a Prodrug of Paracetamol

Acetaminophen overdose is a leading cause of acute liver failure (ALF), and effective treatment depends on early prediction of disease progression. ALF diagnosis currently requires blood collection 24-72 h after APAP ingestion, necessitating repeated tests and hospitalization. Here, we assessed earlier ALF diagnosis using positron emission tomography (PET) imaging of translocator proteins (TSPOs), which are involved in molecular transport, oxidative stress, apoptosis, and energy metabolism, with the radiotracer [18F]GE180. We intraperitoneally administered propacetamol hydrochloride to male C57BL/6 mice to induce ALF. We performed in vivo PET/CT imaging 3 h later using the TSPO-specific radiotracer [18F]GE180 and quantitatively analyzed the PET images by determining the averaged standardized uptake value (SUVav) in the liver parenchyma. We assessed liver TSPO expression levels via real-time polymerase chain reaction, Western blotting, and immunohistochemistry. [18F]GE180 PET imaging 3 h after propacetamol administration (1500 mg/kg) significantly increased liver SUVav compared to controls (p = 0.001). Analyses showed a 10-fold and 4-fold increase in TSPO gene and protein expression, respectively, in the liver, 3 h after propacetamol induction compared to controls. [18F]GE180 PET visualized and quantified propacetamol-induced ALF through TSPO overexpression. These findings highlight TSPO PET's potential as a non-invasive imaging biomarker for early-stage ALF.

An international, multicenter, survey-based analysis of practice and management of acute liver failure

Acute liver failure (ALF) is an acute liver dysfunction with coagulopathy and HE in a patient with no known liver disease. As ALF is rare and large clinical trials are lacking, the level of evidence regarding its management is low-moderate, favoring heterogeneous clinical practice. In this international multicenter survey study, we aimed to investigate the current practice and management of patients with ALF. An online survey targeting physicians who care for patients with ALF was developed by the International Liver Transplantation Society ALF Special-Interest Group. The survey focused on the management and liver transplantation (LT) practices of ALF. Survey questions were summarized overall and by geographic region. A total of 267 physicians completed the survey, with a survey response rate of 21.36%. Centers from all continents were represented. More than 90% of physicians specialized in either transplant hepatology/surgery or anesthesiology/critical care. Two hundred fifty-two (94.4%) respondents' institutions offered LT. A total of 76.8% of respondents' centers had a dedicated liver-intensive or transplant-intensive care unit ( p < 0.001). The median time to LT was within 48 hours in 12.7% of respondents' centers, 72 hours in 35.6%, 1 week in 37.6%, and more than 1 week in 9.6% ( p < 0.001). Deceased donor liver graft (49.6%) was the most common type of graft offered. For consideration of LT, 84.8% of physicians used King's College Criteria, and 41.6% used Clichy Criteria. Significant differences were observed between Asia, Europe, and North America for offering LT, number of LTs performed, volume of patients with ALF, admission to a dedicated intensive care unit, median time to LT, type of liver graft, monitoring HE and intracranial pressure, management of coagulopathy, and utilization of different criteria for LT. In our study, we observed significant geographic differences in the practice and management of ALF. As ALF is rare, multicenter studies are valuable for identifying global practice.

A Novel Bifunctional Fusion Protein (Anti-IL-17A-sST2) Protects against Acute Liver Failure, Modulating the TLR4/MyD88 Pathway and NLRP3 Inflammasome Activation

Acute liver failure (ALF) is a serious inflammatory disorder with high mortality rates, which poses a significant threat to human health. The IL-33/ST2 signal is a crucial regulator in inflammation responses associated with lipopolysaccharide (LPS)-induced macrophages. The IL-17A signaling pathway promotes the release of chemokines and inflammatory cytokines, recruiting neutrophils and T cells under LPS stimulation, thus facilitating inflammatory responses. Here, the potential therapeutic benefits of neutralizing the IL-17A signal and modulating the IL-33/ST2 signal in ALF were investigated. A novel dual-functional fusion protein, anti-IL-17A-sST2, was constructed, which displayed high purity and biological activities. The administration of anti-IL-17A-sST2 resulted in significant anti-inflammatory benefits in ALF mice, amelioration of hepatocyte necrosis and interstitial congestion, and reduction in TNF-α and IL-6. Furthermore, anti-IL-17A-sST2 injection downregulated the expression of TLR4 and NLRP3 as well as important molecules such as MyD88, caspase-1, and IL-1β. The results suggest that anti-IL-17A-sST2 reduced the secretion of inflammatory factors, attenuated the inflammatory response, and protected hepatic function by regulating the TLR4/MyD88 pathway and inhibiting the NLRP3 inflammasome, providing a new therapeutic approach for ALF.

Standard-Volume Is As Effective As High-Volume Plasma Exchange for Patients With Acute Liver Failure

Background/Aims

Acute liver failure (ALF) is associated with fatal outcomes without liver transplantation. Two randomized studies reported standard volume (SV) and high volume (HV) plasma exchange (PLEX) as effective therapeutic modalities for patients with ALF. However, no studies have compared the safety and efficacy of SV with HV PLEX, which we aimed to assess.

Methods

This retrospective study included patients with ALF admitted between March 2021 and March 2023 who underwent PLEX. All patients underwent HV PLEX until May 2022, and then thereafter, SV PLEX was performed. The objectives of the study were to compare transplant-free survival (TFS) at 30 days, efficacy in reducing severity scores, biochemical variables, and adverse events between SV (total plasma volume x 1) and HV (total plasma volume x 1.5-2) PLEX.

Results

Forty two ALF patients (median age: 23.5 years; females: 57.1%; MELD Na: 34.67 ± 6.07; SOFA score- 5.24 ± 1.42) underwent PLEX. Of these, 22 patients underwent SV-PLEX, and 20 underwent HV-PLEX. The mean age, sex, etiology distribution, and severity scores were similar between the groups. The median number of PLEX sessions (2) was similar in both groups. On Kaplan-Meier analysis, TFS was 45.5% in SV group and 45% in HV group (P = 0.76). A comparable decline in total bilirubin, PT/INR, ammonia, and MELD Na scores was noted in both groups. The cumulative number of adverse events was similar between the HV group (77.3%) and SV group (54.5%; P = 0.12).

Conclusions

SV PLEX is safe and as effective as HV PLEX in patients with ALF. Further randomized controlled trials with a larger sample size are needed to validate these findings.

Silymarin: Unveiling its pharmacological spectrum and therapeutic potential in liver diseases-A comprehensive narrative review

Liver diseases, encompassing conditions such as cirrhosis, present a substantial global health challenge with diverse etiologies, including viral infections, alcohol consumption, and non-alcoholic fatty liver disease (NAFLD). The exploration of natural compounds as therapeutic agents has gained traction, notably the herbal remedy milk thistle (Silybum marianum), with its active extract, silymarin, demonstrating remarkable antioxidant and hepatoprotective properties in extensive preclinical investigations. It can protect healthy liver cells or those that have not yet sustained permanent damage by reducing oxidative stress and mitigating cytotoxicity. Silymarin, a natural compound with antioxidant properties, anti-inflammatory effects, and antifibrotic activity, has shown potential in treating liver damage caused by alcohol, NAFLD, drug-induced toxicity, and viral hepatitis. Legalon® is a top-rated medication with excellent oral bioavailability, effective absorption, and therapeutic effectiveness. Its active component, silymarin, has antioxidant and hepatoprotective properties, Eurosil 85® also, a commercial product, has lipophilic properties enhanced by special formulation processes. Silymarin, during clinical trials, shows potential improvements in liver function, reduced mortality rates, and alleviation of symptoms across various liver disorders, with safety assessments showing low adverse effects. Overall, silymarin emerges as a promising natural compound with multifaceted hepatoprotective properties and therapeutic potential in liver diseases.

Larsucosterol: endogenous epigenetic regulator for treating chronic and acute liver diseases

Larsucosterol, a potent endogenous epigenetic regulator, has been reported to play a significant role in lipid metabolism, inflammatory responses, and cell survival. The administration of larsucosterol has demonstrated a reduction in lipid accumulation within hepatocytes and the attenuation of inflammatory responses induced by lipopolysaccharide (LPS) and TNFα in macrophages, alleviating LPS- and acetaminophen (ATMP)-induced multiple organ injury, and decreasing mortalities in animal models. Results from phase 1 and 2 clinical trials have shown that larsucosterol has potential as a biomedicine for the treatment of acute and chronic liver diseases. Recent evidence suggests that larsucosterol is a promising candidate for treating alcohol-associated hepatitis with positive results from a phase 2a clinical trial, and for metabolic dysfunction-associated steatohepatitis (MASH) from a phase 1b clinical trial. In this review, we present a culmination of our recent research efforts spanning two decades. We summarize the discovery, physiological and pharmacological mechanisms, and clinical applications of larsucosterol. Furthermore, we elucidate the pathophysiological pathways of metabolic dysfunction-associated steatotic liver diseases (MASLD), metabolic dysfunction-associated steatohepatitis (MASH), and acute liver injuries. A central focus of the review is the exploration of the therapeutic potential of larsucosterol in treating life-threatening conditions, including acetaminophen overdose, endotoxin shock, MASLD, MASH, hepatectomy, and alcoholic hepatitis.

Liver transplantation for severe hepatic trauma: A multicenter analysis from the UNOS data set

BACKGROUND

Orthotopic liver transplantation (OLT) is rarely indicated after hepatic trauma but it can be the only therapeutic option in some patients. There are scarce data analyzing the surgical outcomes of OLT after trauma.

METHODS

We used the UNOS data set to identify patients who underwent OLT for trauma from 1987 to 2022 and compared them to a cohort of patients transplanted for other indications. Cox proportional hazard and multivariable logistic regression analyses were performed to assess predictors of graft and patient survival.

RESULTS

Seventy-two patients underwent OLT for trauma during the study period. Patients with trauma were more frequently on mechanical ventilation at the time of transplantation (26.4% vs. 7.6%, p < 0.001) and had a greater incidence of pretransplant portal vein thrombosis (12.5% vs. 4%, p = 0.002). Our 4:1 matched analysis showed that trauma patients had significantly shorter wait times, higher incidence of pretransplant portal vein thrombosis and prolonged length of stay. Trauma was associated with decreased overall graft survival (hazards ratio, 1.42; 95% confidence interval, 1.01-1.98), and increased length of stay ( p = 0.048). There were no significant differences in long-term patient survival.

CONCLUSION

Unique physiological and vascular challenges after severe hepatic trauma might be associated with decreased graft survival in patients requiring liver transplantation.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level III.

Acute liver failure

ABSTRACT

Acute liver failure, commonly caused by acetaminophen overdose, is associated with numerous systemic complications including cerebral edema, hypotension, acute kidney injury, and infection. Management is primarily supportive, with an emphasis on excellent neurocritical care. Although some antidotes and targeted treatments exist, the only definitive treatment remains orthotopic liver transplant.

The p21+ perinecrotic hepatocytes produce the chemokine CXCL14 after a severe acetaminophen overdose promoting hepatocyte injury and delaying regeneration

Fifty percent of all acute liver failure (ALF) cases in the United States are due to acetaminophen (APAP) overdose. Assessment of canonical features of liver injury, such as plasma alanine aminotransferase activities are poor predictors of acute liver failure (ALF), suggesting the involvement of additional mechanisms independent of hepatocyte death. Previous work demonstrated a severe overdose of APAP results in impaired regeneration, the induction of senescence by p21, and increased mortality. We hypothesized that a discrete population of p21+ hepatocytes acquired a secretory phenotype that directly impedes liver recovery after a severe APAP overdose. Leveraging in-house human APAP explant liver and publicly available single-nuclei RNAseq data, we identified a subpopulation of p21+ hepatocytes enriched in a unique secretome of factors, such as CXCL14. Spatial transcriptomics in the mouse model of APAP overdose confirmed the presence of a p21+ hepatocyte population that directly surrounded the necrotic areas. In both male and female mice, we found a dose-dependent induction of p21 and persistent circulating levels of the p21-specific constituent, CXCL14, in the plasma after a severe APAP overdose. In parallel experiments, we targeted either the putative senescent hepatocytes with the senolytic drugs, dasatinib and quercetin, or CXCL14 with a neutralizing antibody. We found that targeting CXCL14 greatly enhanced liver recovery after APAP-induced liver injury, while targeting senescent hepatocytes had no effect. These data support the conclusion that the sustained induction of p21 in hepatocytes with persistent CXCL14 secretion are critical mechanistic events leading to ALF in mice and human patients.

Acetaminophen overdose causes a breach of the blood-bile barrier in mice but not in rats

Acetaminophen (APAP) is known to cause a breach of the blood-bile barrier in mice that, via a mechanism called futile bile acid (BA) cycling, increases BA concentrations in hepatocytes above cytotoxic thresholds. Here, we compared this mechanism in mice and rats, because both species differ massively in their susceptibility to APAP and compared the results to available human data. Dose and time-dependent APAP experiments were performed in male C57BL6/N mice and Wistar rats. The time course of BA concentrations in liver tissue and in blood was analyzed by MALDI-MSI and LC-MS/MS. APAP and its derivatives were measured in the blood by LC-MS. APAP-induced liver damage was analyzed by histopathology, immunohistochemistry, and by clinical chemistry. In mice, a transient increase of BA in blood and in peri-central hepatocytes preceded hepatocyte death. The BA increase coincided with oxidative stress in liver tissue and a compromised morphology of bile canaliculi and immunohistochemically visualized tight junction proteins. Rats showed a reduced metabolic activation of APAP compared to mice. However, even at very high doses that caused cell death of hepatocytes, no increase of BA concentrations was observed neither in liver tissue nor in the blood. Correspondingly, no oxidative stress was detectable, and the morphology of bile canaliculi and tight junction proteins remained unaltered. In conclusion, different mechanisms cause cell death in rats and mice, whereby oxidative stress and a breach of the blood-bile barrier are seen only in mice. Since transient cholestasis also occurs in human patients with APAP overdose, mice are a clinically relevant species to study APAP hepatotoxicity but not rats.

Circulating myostatin levels as a prognostic biomarker in patients with acute liver failure and late-onset hepatic failure

AIM

Myostatin is a myokine involved in muscle mass regulation. The associations between circulating myostatin levels and clinical characteristics in patients with acute liver failure (ALF) and late-onset hepatic failure (LOHF) are unclear.

METHODS

In this retrospective study, 51 patients with ALF or LOHF were included. Serum myostatin was measured using an enzyme-linked immunosorbent assay.

RESULTS

Myostatin levels were significantly lower in patients with ALF and LOHF than in controls (ALF/LOHF: 2522 pg/mL, controls: 3853 pg/mL, p = 0.003). The prevalence of low myostatin in deceased patients was significantly higher than that in spontaneous survivors and patients who underwent liver transplantation. Patients with low myostatin levels had a high incidence of complications. There was a positive correlation between the psoas muscle index and serum myostatin levels. Patients with low myostatin levels had shorter 1-year transplant-free survival and shorter 1-year overall survival than patients with high myostatin levels. Low serum myostatin levels were associated with poor prognosis independent of the Japanese scoring system for ALF ≥3, King's College criteria, or model for end-stage liver disease score >30.5. The combination of serum myostatin levels and prognostic models for ALF significantly stratified patients according to 1-year prognosis.

CONCLUSIONS

Low serum myostatin levels were associated with a low psoas muscle index, complication rate, and poor prognosis in patients with ALF and LOHF. Assessment of circulating myostatin levels may improve the prediction of outcomes in patients with ALF and LOHF.

Hepatic Sirt6 activation abrogates acute liver failure

Acute liver failure (ALF) is a deadly illness due to insufficient detoxification in liver induced by drugs, toxins, and other etiologies, and the effective treatment for ALF is very limited. Among the drug-induced ALF, acetaminophen (APAP) overdose is the most common cause. However, the molecular mechanisms underlying APAP hepatoxicity remain incompletely understood. Sirtuin 6 (Sirt6) is a stress responsive protein deacetylase and plays an important role in regulation of DNA repair, genomic stability, oxidative stress, and inflammation. Here, we report that genetic and pharmacological activation of Sirt6 protects against ALF in mice. We first observed that Sirt6 expression was significantly reduced in the liver tissues of human patients with ALF and mice treated with an overdose of APAP. Then we developed an inducible Sirt6 transgenic mice for Cre-mediated overexpression of the human Sirt6 gene in systemic (Sirt6-Tg) and hepatic-specific (Sirt6-HepTg) manners. Both Sirt6-Tg mice and Sirt6-HepTg mice exhibited the significant protection against APAP hepatoxicity. In contrast, hepatic-specific Sirt6 knockout mice exaggerated APAP-induced liver damages. Mechanistically, Sirt6 attenuated APAP-induced hepatocyte necrosis and apoptosis through downregulation of oxidative stress, inflammation, the stress-activated kinase JNK activation, and apoptotic caspase activation. Moreover, Sirt6 negatively modulated the level and activity of poly (ADP-ribose) polymerase 1 (PARP1) in APAP-treated mouse liver tissues. Importantly, the specific Sirt6 activator MDL-800 exhibited better therapeutic potential for APAP hepatoxicity than the current drug acetylcysteine. Furthermore, in the model of bile duct ligation induced ALF, hepatic Sirt6-KO exacerbated, but Sirt6-HepTg mitigated liver damage. Collectively, our results demonstrate that Sirt6 protects against ALF and suggest that targeting Sirt6 activation could be a new therapeutic strategy to alleviate ALF.

Evaluation of capillary miR-122 as a prognostic biomarker of paracetamol-induced liver toxicity

INTRODUCTION

Paracetamol (acetaminophen) overdose is a leading cause of acute liver failure in many Western countries. Diagnostic tools for this poisoning may be suboptimal in some cases and new biomarkers have been investigated. We investigated the role of capillary microRNA-122 (miR-122) as a prognostic biomarker of liver injury in the clinical management of patients with paracetamol overdose.

METHODS

In a paracetamol overdose patient cohort, miR-122 was measured by quantitative polymerase chain reaction in a blood drop obtained by a finger prick at the end of an antidote cycle treatment with N-acetylcysteine treatment (12 h). Liver injury was defined as serum alanine aminotransferase (ALT) activity > 100 IU/L collected at 10 or 20 h after the start of treatment. Pearson's correlation analyses were performed.

RESULTS

In patients with paracetamol overdose, capillary miR-122 was positively correlated with ALT measured at 10 h and at 20 h (r = 0.83, P < 0.0001; r = 0.96, P < 0.0001, respectively).

CONCLUSION

This work supports the potential use of capillary miR-122 as a prognostic biomarker of liver injury throughout clinical management of patients with paracetamol overdose. Capillary miR-122 can be measured in a blood drop collected by a finger prick, a minimally invasive diagnostic test for patient stratification.

Acute kidney injury in acute liver failure: A narrative review

Acute kidney injury (AKI) is a frequent complication of acute liver failure (ALF) and it worsens the already worse prognoses of ALF. ALF is an uncommon disease, with varying etiologies and varying definitions in different parts of the world. There is limited literature on the impact of AKI on the outcome of ALF with or without transplantation. The multifaceted etiology of AKI in ALF encompasses factors such as hemodynamic instability, systemic inflammation, sepsis and direct nephrotoxicity. Indications of renal replacement therapy (RRT) for AKI in ALF patients extend beyond the conventional criteria for dialysis and continuous renal replacement therapy (CRRT) may have a role in transplant-free survival or bridge to liver transplantation (LT). LT is a life-saving option for ALF, so despite somewhat lower survival rates of LT in ALF patients with AKI, LT is not usually deferred. In this review, we will discuss the guidelines' recommended definition and classification of AKI in ALF, the impact of AKI in ALF, the pathophysiology of AKI and the role of CRRT and LT in ALF patients with AKI.

Comparative analysis of gene expression between mice and humans in acetaminophen-induced liver injury by integrating bioinformatics analysis

OBJECTIVE

Mice are routinely utilized as animal models of drug-induced liver injury (DILI), however, there are significant differences in the pathogenesis between mice and humans. This study aimed to compare gene expression between humans and mice in acetaminophen (APAP)-induced liver injury (AILI), and investigate the similarities and differences in biological processes between the two species.

METHODS

A pair of public datasets (GSE218879 and GSE120652) obtained from GEO were analyzed using "Limma" package in R language, and differentially expressed genes (DEGs) were identified, including co-expressed DEGs (co-DEGs) and specific-expressed DEGS (specific-DEGs). Analysis of Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed analyses for specific-DEGs and co-DEGs. The co-DEGs were also used to construct transcription factor (TF)-gene network, gene-miRNA interactions network and protein-protein interaction (PPI) network for analyzing hub genes.

RESULTS

Mouse samples contained 1052 up-regulated genes and 1064 down-regulated genes, while human samples contained 1156 up-regulated genes and 1557 down-regulated genes. After taking the intersection between the DEGs, only 154 co-down-regulated and 89 co-up-regulated DEGs were identified, with a proportion of less than 10%. It was suggested that significant differences in gene expression between mice and humans in drug-induced liver injury. Mouse-specific-DEGs predominantly engaged in processes related to apoptosis and endoplasmic reticulum stress, while human-specific-DEGs were concentrated around catabolic process. Analysis of co-regulated genes reveals showed that they were mainly enriched in biosynthetic and metabolism-related processes. Then a PPI network which contains 189 nodes and 380 edges was constructed from the co-DEGs and two modules were obtained by Mcode. We screened out 10 hub genes by three algorithms of Degree, MCC and MNC, including CYP7A1, LSS, SREBF1, FASN, CD44, SPP1, ITGAV, ANXA5, LGALS3 and PDGFRA. Besides, TFs such as FOXC1, HINFP, NFKB1, miRNAs like mir-744-5p, mir-335-5p, mir-149-3p, mir-218-5p, mir-10a-5p may be the key regulatory factors of hub genes.

CONCLUSIONS

The DEGs of AILI mice models and those of patients were compared, and common biological processes were identified. The signaling pathways and hub genes in co-expression were identified between mice and humans through a series of bioinformatics analyses, which may be more valuable to reveal molecular mechanisms of AILI.

Region-specific cellular and molecular basis of liver regeneration after acute pericentral injury

Liver injuries often occur in a zonated manner. However, detailed regenerative responses to such zonal injuries at cellular and molecular levels remain largely elusive. By using a fate-mapping strain, Cyp2e1-DreER, to elucidate liver regeneration after acute pericentral injury, we found that pericentral regeneration is primarily compensated by the expansion of remaining pericentral hepatocytes, and secondarily by expansion of periportal hepatocytes. Employing single-cell RNA sequencing, spatial transcriptomics, immunostaining, and in vivo functional assays, we demonstrated that the upregulated expression of the mTOR/4E-BP1 axis and lactate dehydrogenase A in hepatocytes contributes to pericentral regeneration, while activation of transforming growth factor β (TGF-β1) signaling in the damaged area mediates fibrotic responses and inhibits hepatocyte proliferation. Inhibiting the pericentral accumulation of monocytes and monocyte-derived macrophages through an Arg-Gly-Asp (RGD) peptide-based strategy attenuates these cell-derived TGF-β1 signalings, thus improving pericentral regeneration. Our study provides integrated and high-resolution spatiotemporal insights into the cellular and molecular basis of pericentral regeneration.