Epidemiology of liver failure

Hepatic impairment as a risk factor of adverse drug reactions

There are a lot of clinical variants of hepatic impairment ranging from asymptomatic increase in transaminases to acute liver failure and fulminant hepatitis. Hepatic impairment is a polietiologic syndrome. According to the epidemiological study conducted in the United States (19982008), the main causes of hepatic impairment were paracetamol overdose (46%), idiopathic liver dysfunction (14%), other drugs (excluding paracetamol, 11%), viral hepatitis B (7%), other infectious and non-infectious diseases with liver damage (except for viral hepatitis) 7%, autoimmune hepatitis (5%), ischemic hepatitis (syn. hypoxic hepatitis, liver infarction) 4%, viral hepatitis A (3%) and Wilson's disease (2%). Hepatic impairment have a direct impact on the pharmacokinetics and pharmacodynamics of drugs decreasing clearance, elimination and excretion of drugs. Also Transjugular intrahepatic porto-systemic shunts, which are often used to treat portal hypertension in patients with liver cirrhosis, can significantly reduce the presystemic elimination of drugs, thereby increasing their absorption. Moreover, in patients with liver cirrhosis, concomitant renal dysfunction also requires an adjustment of the dose of drugs. Correction of pharmacotherapy in accordance to pharmacokinetic and pharmacodynamic changes of drugs ingested by patients with impaired liver function will improve the quality of medical care and reduce the risks of adverse drug reactions.

Mass Spectrometry-Based Proteomics Reveal Alcohol Dehydrogenase 1B as a Blood Biomarker Candidate to Monitor Acetaminophen-Induced Liver Injury

Acute liver injury (ALI) is a severe disorder resulting from excessive hepatocyte cell death, and frequently caused by acetaminophen intoxication. Clinical management of ALI progression is hampered by the dearth of blood biomarkers available. In this study, a bioinformatics workflow was developed to screen omics databases and identify potential biomarkers for hepatocyte cell death. Then, discovery proteomics was harnessed to select from among these candidates those that were specifically detected in the blood of acetaminophen-induced ALI patients. Among these candidates, the isoenzyme alcohol dehydrogenase 1B (ADH1B) was massively leaked into the blood. To evaluate ADH1B, we developed a targeted proteomics assay and quantified ADH1B in serum samples collected at different times from 17 patients admitted for acetaminophen-induced ALI. Serum ADH1B concentrations increased markedly during the acute phase of the disease, and dropped to undetectable levels during recovery. In contrast to alanine aminotransferase activity, the rapid drop in circulating ADH1B concentrations was followed by an improvement in the international normalized ratio (INR) within 10–48 h, and was associated with favorable outcomes. In conclusion, the combination of omics data exploration and proteomics revealed ADH1B as a new blood biomarker candidate that could be useful for the monitoring of acetaminophen-induced ALI.

Human Herpesviruses Increase the Severity of Hepatitis

Simple Summary

More than 300 million people worldwide suffer from hepatitis B or hepatitis C and more than 1 million people die each year from cirrhosis and liver cancer. In some cases, the nature of hepatitis remains unclear. The purpose of this research was to assess the prevalence of human herpesviruses (cytomegalovirus, Epstein–Barr virus, and herpesvirus type 6) in patients with hepatitis, and to examine their effect on the disease severity. In the clinical materials of 377 patients with acute or chronic hepatitis, DNA of these three herpesviruses was detected in the blood in 13.5% of patients with viral hepatitis B or C and in 10.1% of patients with hepatitis of unspecified etiology. The cirrhosis was diagnosed in patients with herpesviruses 3 times more often than in patients without them. In patients with hepatitis C, the incidence of herpesviruses was higher in the tissue samples of liver biopsies (38.7%) than in the blood. Clinical and virological indicators of hepatitis were considerably higher in the patients with coinfection. Since in patients with hepatitis the presence of herpesviruses is associated with a more severe course of the disease, the detection, and herpesvirus DNA monitoring will help to adjust the course of therapy.

Abstract

Acute and chronic liver diseases are a major global public health problem; nevertheless, the etiology of 12–30% of cases remains obscure. The purpose of this research was to study the incidence of human herpesviruses (HHVs) cytomegalovirus, Epstein–Barr virus (EBV), and HHV-6 in patients with hepatitis and to examine the effect of HHV on the disease severity. We studied the clinical materials of 259 patients with hepatitis treated in Infectious Clinic n.1 (Moscow) and the archived materials of 118 patients with hepatitis C. HHV DNA was detected in the whole blood in 13.5% of patients with hepatitis B or C and in 10.1% of patients with hepatitis of unspecified etiology. EBV demonstrated the highest incidence (58.1%). Cirrhosis was diagnosed in 50% of patients with HHV and in 15.6% of patients without HHV. In patients with hepatitis C, the frequency of HHV was higher in liver biopsy (38.7%) compared to blood. The clinical and virological indicators of hepatitis were considerably higher in patients with coinfection. Conclusion: HHV detected in patients with viral hepatitis has been associated with a significant effect on the severity of the disease, and we suggest monitoring HHV DNA in patients with severe hepatitis and/or poor response to antiviral drugs.

Research progress on the protective effects of licorice-derived 18β-glycyrrhetinic acid against liver injury

The first description of the medical use of licorice appeared in "Shennong Bencao Jing", one of the well-known Chinese herbal medicine classic books dated back to 220-280 AD. As one of the most commonly prescribed Chinese herbal medicine, licorice is known as "Guo Lao", meaning "a national treasure" in China. Modern pharmacological investigations have confirmed that licorice possesses a number of biological activities, such as antioxidation, anti-inflammatory, antiviral, immune regulation, and liver protection. 18β-glycyrrhetinic acid is one of the most extensively studied active integrants of licorice. Here, we provide an overview of the protective effects of 18β-glycyrrhetinic acid against various acute and chronic liver diseases observed in experimental models, and summarize its pharmacological effects and potential toxic/side effects at higher doses. We also make additional comments on the important areas that may warrant further research to support appropriate clinical applications of 18β-glycyrrhetinic acid and avoid potential risks.

Therapeutic Potential of Umbilical Cord Stem Cells for Liver Regeneration

The liver is a vital organ for life and the only internal organ that is capable of natural regeneration. Although the liver has high regeneration capacity, excessive hepatocyte death can lead to liver failure. Various factors can lead to liver damage including drug abuse, some natural products, alcohol, hepatitis, and autoimmunity. Some models for studying liver injury are APAP-based model, Fas ligand (FasL), D-galactosamine/endotoxin (Gal/ET), Concanavalin A, and carbon tetrachloride-based models. The regeneration of the liver can be carried out using umbilical cord blood stem cells which have various advantages over other stem cell types used in liver transplantation. UCB-derived stem cells lack tumorigenicity, have karyotype stability and high immunomodulatory, low risk of graft versus host disease (GVHD), low risk of transmitting somatic mutations or viral infections, and low immunogenicity. They are readily available and their collection is safe and painless. This review focuses on recent development and modern trends in the use of umbilical cord stem cells for the regeneration of liver fibrosis.

Bone Marrow-Derived Mesenchymal Stem Cells Isolated from Patients with Cirrhosis and Healthy Volunteers Show Comparable Characteristics

Background and Objectives

Autologous or allogeneic bone marrow-derived mesenchymal stem cells (BMSCs) have been applied in clinical trials to treat liver disease. However, only a few studies are comparing the characteristics of autologous MSCs from patients and allogeneic MSCs from normal subjects.

Methods and Results

We compared the characteristics of BMSCs (BCs and BPs, respectively) isolated from six healthy volunteers and six patients with cirrhosis. In passage 3 (P3), senescent population and expression of p53 and p21 were slightly higher in BPs, but the average population doubling time for P3–P5 in BPs was approximately 65.3±11.1 h, which is 18.4 h shorter than that in BCs (83.7±9.2 h). No difference was observed in the expression of CD73, CD90, or CD105 between BCs and BPs. Adipogenic differentiation slightly increased in BCs, but the expression levels of leptin, peroxisome proliferator-activated receptor γ, and CCAAT-enhancer-binding protein α did not vary between differentiated BCs and BPs. While ATP and reactive oxygen species levels were slightly lower in BPs, mitochondrial membrane potential, oxygen consumption rate, and expression of mitochondria-related genes such as cytochrome c oxidase 1 were not significantly different between BCs and BPs.

Conclusions

Taken together, there are marginal differences in the proliferation, differentiation, and mitochondrial activities of BCs and BPs, but both BMSCs from patients with cirrhosis and healthy volunteers show comparable characteristics.

Circadian Control of Inflammasome Pathways: Implications for Circadian Medicine

The innate immune system senses “non-self” molecules derived from pathogens (PAMPs) as well as endogenous damage-associated molecular patterns (DAMPs) and promotes sterile inflammation that is necessary for injury resolution, tissue repair/regeneration, and homeostasis. The NOD-, LRR- and pyrin domain containing protein 3 (NLRP3) is an innate immune signaling complex whose assembly and activation can be triggered by various signals ranging from microbial molecules to ATP or the abnormal accumulation of crystals, thus leading to IL-1β and IL-18 maturation and secretion. Deregulation of the NLRP3 signaling cascade is associated with numerous inflammatory and metabolic diseases including rheumatoid arthritis, gout, atherosclerosis or type 2 diabetes. Interestingly, the circadian clock controls numerous inflammatory processes while clock disruption leads to or exacerbates inflammation. Recently, the biological clock was demonstrated to control NLRP3 expression and activation, thereby controlling IL-1β and IL-18 secretion in diverse tissues and immune cells, particularly macrophages. Circadian oscillations of NLRP3 signaling is lost in models of clock disruption, contributing to the development of peritonitis, hepatitis, or colitis. Sterile inflammation is also an important driver of atherosclerosis, and targeting the production of IL-1β has proven to be a promising approach for atherosclerosis management in humans. Interestingly, the extent of injury after fulminant hepatitis or myocardial infarction is time-of-day dependent under the control of the clock, and chronotherapy represents a promising approach for the management of pathologies involving deregulation of NLRP3 signaling.

Sequential liver and haematopoietic stem cell transplantation in a case of fulminant hepatitis associated liver failure and aplastic anaemia

The management of severe aplastic anaemia is particularly challenging when it occurs in the context of recent liver transplantation. Rapid identification of a suitable donor followed by allogeneic haematopoietic stem cell transplantation is the only curative option. This scenario is often complicated by potentially life-threatening infections that develop as a consequence of immunosuppression. Alternative donor transplantation using suitably matched unrelated donors can be potentially life-saving when suitably matched sibling donors are unavailable. Above all, a dedicated interdisciplinary approach with seamless communication between hepatology, transplant surgery, haematology, and stem cell transplant services is essential to achieving optimal outcomes. Herein, we describe a case of severe hepatitis leading to hepatic failure who was treated with liver transplantation from a deceased donor, and later received an allogeneic haematopoietic stem cell transplantation from a matched unrelated donor for hepatitis-associated aplastic anaemia.

Artificial liver research output and citations from 2004 to 2017: a bibliometric analysis

Background

Researches on artificial livers greatly contribute to the clinical treatments for liver failure. This study aimed to evaluate the research output of artificial livers and citations from 2004 to 2017 through a bibliometric analysis.

Methods

A list of included articles on artificial livers were generated after a comprehensive search of the Web of Science Core Collection (from 2004 to 2017) with the following basic information: number of publications, citations, publication year, country of origin, authors and authorship, funding source, journals, institutions, keywords, and research area.

Results

A total of 968 included articles ranged from 47 citations to 394 citations with a fluctuation. The publications were distributed in 12 countries, led by China (n = 212) and the US (n = 207). There were strong correlations of the number of citations with authors (r ² = 0.133, p < 0.001), and countries (r ² = 0.275, p < 0.001), while no correlations of the number of citations with the years since publication (r ² = 0.016, p = 0.216), and funding (r ² < 0.001, p = 0.770) were identified. Keyword analysis demonstrated that with the specific change of "acute liver failure," decrease in "bioartificial livers" and "hepatocyte," and increase in "tissue engineering" were identified. The top 53 cited keyword and keyword plus (including some duplicates counts) were identified, led by bioartificial liver (405 citations) and hepatocyte (248 citations). The top 50 cited keywords bursts were mainly "Blood" (2004-2008), "hepatocyte like cell" (2008-2015), and "tissue engineering" (2014-2017). All keywords could be classified into four categories: bioartificial livers (57.40%), blood purification (25.00%), clinical (14.81%), and other artificial organs (2.78%).

Discussion

This study shows the process and tendency of artificial liver research with a comprehensive analysis on artificial livers. However, although it seems that the future of artificial livers seems brighter for hepatocyte transplantation, the systems of artificial livers now are inclined on focusing on blood purification, plasma exchange, etc.

The dawn of precision medicine in HIV: state of the art of pharmacotherapy

INTRODUCTION

Combination antiretroviral therapy (ART) reduces viral load to under the limit of detection, successfully decreasing HIV-related morbidity and mortality. Due to viral mutations, complex drug combinations and different patient response, there is an increasing demand for individualized treatment options for patients.

AREAS COVERED

This review first summarizes the pharmacokinetic and pharmacodynamic profile of clinical first-line drugs, which serves as guidance for antiretroviral precision medicine. Factors which have influential effects on drug efficacy and thus precision medicine are discussed: patients' pharmacogenetic information, virus mutations, comorbidities, and immune recovery. Furthermore, strategies to improve the application of precision medicine are discussed.

EXPERT OPINION

Precision medicine for ART requires comprehensive information on the drug, virus, and clinical data from the patients. The clinically available genetic tests are a good starting point. To better apply precision medicine, deeper knowledge of drug concentrations, HIV reservoirs, and efficacy associated genes, such as polymorphisms of drug transporters and metabolizing enzymes, are required. With advanced computer-based prediction systems which integrate more comprehensive information on pharmacokinetics, pharmacodynamics, pharmacogenomics, and the clinically relevant information of the patients, precision medicine will lead to better treatment choices and improved disease outcomes.

Connexin hemichannel inhibition reduces acetaminophen-induced liver injury in mice

Historically, connexin hemichannels have been considered as structural precursors of gap junctions. However, accumulating evidence points to independent roles for connexin hemichannels in cellular signaling by connecting the intracellular compartment with the extracellular environment. Unlike gap junctions, connexin hemichannels seem to be mainly activated in pathological processes. The present study was set up to test the potential involvement of hemichannels composed of connexin32 and connexin43 in acute hepatotoxicity induced by acetaminophen. Prior to this, in vitro testing was performed to confirm the specificity and efficacy of TAT-Gap24 and TAT-Gap19 in blocking connexin32 and connexin43 hemichannels, respectively. Subsequently, mice were overdosed with acetaminophen followed by treatment with TAT-Gap24 or TAT-Gap19 or a combination of both after 1.5h. Sampling was performed 3, 6, 24 and 48h following acetaminophen administration. Evaluation of the effects of connexin hemichannel inhibition was based on a series of clinically relevant read-outs, measurement of inflammatory cytokines and oxidative stress. Subsequent treatment of acetaminophen-overdosed mice with TAT-Gap19 only marginally affected liver injury. In contrast, a significant reduction in serum alanine aminotransferase activity was found upon administration of TAT-Gap24 to intoxicated animals. Furthermore, co-treatment of acetaminophen-overdosed mice with both peptides revealed an additive effect as even lower serum alanine aminotransferase activity was observed. Blocking of connexin32 or connexin43 hemichannels individually was found to decrease serum quantities of pro-inflammatory cytokines, while no effects were observed on the occurrence of hepatic oxidative stress. This study shows for the first time a role for connexin hemichannels in acetaminophen-induced acute liver failure.

Inhibition of pannexin1 channels alleviates acetaminophen-induced hepatotoxicity

Pannexins constitute a relatively new family of transmembrane proteins that form channels linking the cytoplasmic compartment with the extracellular environment. The presence of pannexin1 in the liver has been documented previously, where it underlies inflammatory responses, such as those occurring upon ischemia-reperfusion injury. In the present study, we investigated whether pannexin1 plays a role in acute drug-induced liver toxicity. Hepatic expression of pannexin1 was characterized in a mouse model of acetaminophen-induced hepatotoxicity. Subsequently, mice were overdosed with acetaminophen followed by treatment with the pannexin1 channel inhibitor 10Panx1. Sampling was performed 1, 3, 6, 24 and 48 h after acetaminophen administration. Evaluation of the effects of pannexin1 channel inhibition was based on a number of clinically relevant readouts, including protein adduct formation, measurement of aminotransferase activity and histopathological examination of liver tissue as well as on a series of markers of inflammation, oxidative stress and regeneration. Although no significant differences were found in histopathological analysis, pannexin1 channel inhibition reduced serum levels of alanine and aspartate aminotransferase. This was paralleled by a reduced amount of neutrophils recruited to the liver. Furthermore, alterations in the oxidized status were noticed with upregulation of glutathione levels upon suppression of pannexin1 channel opening. Concomitant promotion of regenerative activity was detected as judged on increased proliferating cell nuclear antigen protein quantities in 10Panx1-treated mice. Pannexin1 channels are important actors in liver injury triggered by acetaminophen. Inhibition of pannexin1 channel opening could represent a novel approach for the treatment of drug-induced hepatotoxicity.

Connexin-based signaling and drug-induced hepatotoxicity

Being critical mediators of liver homeostasis, connexins and their channels are frequently involved in liver toxicity. In the current paper, specific attention is paid to actions of hepatotoxic drugs on these communicative structures. In a first part, an overview is provided on the structural, regulatory and functional properties of connexin-based channels in the liver. In the second part, documented effects of acetaminophen, hypolipidemic drugs, phenobarbital and methapyriline on connexin signaling are discussed. Furthermore, the relevance of this subject for the fields of clinical and in vitro toxicology is demonstrated.

Relevance for patients: The role of connexin signaling in drug-induced hepatotoxicity may be of high clinical relevance, as it offers perspectives for the therapeutic treatment of such insults by interfering with connexin channel opening.

Toxicant-Induced Hepatic Injury

The sudden failure of a previously healthy and functioning liver is a dramatic and devastating event. Acute liver failure is the common final pathway of a multitude of conditions and insults, all of which result in massive hepatic necrosis or loss of normal hepatic function. The ensuing multiorgan system failure frequently has a fatal outcome, with mortality rates in most series ranging from approximately 55% to 95% [1]. Acute liver failure (ALF, previously often referred to as fulminant hepatic failure (FHF)) knows no age boundaries, with many cases occurring in those younger than 30 years. Short of excellent intensive care unit (ICU) support and liver transplantation in selected cases, few viable treatment options are available. Over the past few decades, however, survival has been improved by anticipation, recognition, and early treatment of associated complications, as well as the application of prognostic criteria for early identification of patients requiring liver transplantation (along with improvement in the techniques and science of transplantation itself). The etiology of ALF varies from country to country and the incidence change over time. Paracetamol (acetaminophen) has now replaced viral hepatitis as the leading cause of ALF [2]. In a study from London including 310 patients with ALF in the period 1994–2004, 42% of the cases were caused by paracetamol [3], whereas this was only the cause in 2% of 267 patients in Spain from 1992 to 2000 [4]. However, less than 10% of all liver transplants are performed in patients with ALF [5, 6].

Ginseng for Liver Injury: Friend or Foe?

Panax sp., including Panax ginseng Meyer, Panax quiquifolius L., or Panax notoginseng (Burk.) FH Chen, have been used as functional foods or for traditional Chinese medicine for diabetes, inflammation, stress, aging, hepatic injury, and cancer. In recent decades, a number of both in vitro and in vivo experiments as well as human studies have been conducted to investigate the efficacy and safety of various types of ginseng samples and their components. Of these, the hepatoprotective and hepatotoxic effects of ginseng and their ginsenosides and polysaccharides are reviewed and summarized.

A non-hepatotropic parasite infection increases mortality in the acetaminophen-induced acute liver failure murine model: possible roles for IL-5 and IL-6

We evaluated the effects of a non-hepatotropic parasite infection (Taenia crassiceps) on the outcome of acetaminophen-induced acute liver failure in mice. Uninfected and T. crassiceps infected mice orally received either 300 mg/kg acetaminophen or water as vehicle (n = 5 per group). Survival analysis, hepatocyte necrosis, alanine aminotransferase (ALT) levels, CYP2E1 protein, interleukin (IL-) 5, and IL-6 were assessed for all groups. All infected mice died within 16 h after exposure to acetaminophen (Tc+APAP group), whereas only one-third of uninfected animals exposed to acetaminophen (APAP group) died. Uninfected (Control group) and infected (Tc group) mice that received the vehicle showed no liver damage. Tc+APAP mice exhibited massive liver necrosis characterised by marked balloning degeneration of hepatocytes and higher serum ALT compared to Control, Tc, and APAP animals. Liver tissue from Tc+APAP mice also displayed increased expression of CYP2E1 protein and higher mRNA and protein levels of IL-5 and IL-6 compared to the other groups. These findings suggest that non-hepatotropic parasite infections may increase mortality following acute liver failure by promoting hepatocyte necrosis via IL-5 and IL-6-dependent CYP2E1 overproduction. This study identifies new potential risk factors associated with severe acute liver failure in patients.

Chitohexaose protects against acetaminophen-induced hepatotoxicity in mice

Acetaminophen (N-acetyl-para-aminophenol (APAP)) toxicity causes acute liver failure by inducing centrilobular hepatic damage as a consequence of mitochondrial oxidative stress. Sterile inflammation, triggered by hepatic damage, facilitates gut bacterial translocation leading to systemic inflammation; TLR4-mediated activation by LPS has been shown to have a critical role in APAP-mediated hepatotoxicity. In this study, we demonstrate significant protection mediated by chitohexaose (Chtx) in mice challenged with a lethal dose of APAP (400 mg/kg b.w.). Decreased mortality by Chtx was associated with reduced hepatic damage, increased peritoneal migration of neutrophils, decreased mRNA expression of IL-1β as well as inhibition of inflammasome activation in liver. Further, an alternate mouse model of co-administration of a sublethal doses of APAP (200 mg/kg b.w.) and LPS (5 mg/kg b.w.) operating synergistically and mediating complete mortality was developed. Overwhelming inflammation, characterized by increased inflammatory cytokines (TNF-α, IL-1β and so on) in liver as well as in circulation and mortality was demonstrable in this model. Also, Chtx administration mediated significant reversal of mortality in APAP+LPS co-administered mice, which was associated with reduced IL-1β in liver and plasma cytokines in this model. In conclusion, Chtx being a small molecular weight linear carbohydrate offers promise for clinical management of liver failure associated with APAP overdose.

Involvement of connexin43 in acetaminophen-induced liver injury

BACKGROUND AND AIMS

Being goalkeepers of liver homeostasis, gap junctions are also involved in hepatotoxicity. However, their role in this process is ambiguous, as gap junctions can act as both targets and effectors of liver toxicity. This particularly holds true for drug-induced liver insults. In the present study, the involvement of connexin26, connexin32 and connexin43, the building blocks of liver gap junctions, was investigated in acetaminophen-induced hepatotoxicity.

METHODS

C57BL/6 mice were overdosed with 300mg/kg body weight acetaminophen followed by analysis of the expression and localization of connexins as well as monitoring of hepatic gap junction functionality. Furthermore, acetaminophen-induced liver injury was compared between mice genetically deficient in connexin43 and wild type littermates. Evaluation of the toxicological response was based on a set of clinically relevant parameters, including protein adduct formation, measurement of alanine aminotransferase activity, cytokines and glutathione.

RESULTS

It was found that gap junction communication deteriorates upon acetaminophen intoxication in wild type mice, which is associated with a switch in mRNA and protein production from connexin32 and connexin26 to connexin43. The upregulation of connexin43 expression is due, at least in part, to de novo production by hepatocytes. Connexin43-deficient animals tended to show increased liver cell death, inflammation and oxidative stress in comparison with wild type counterparts.

CONCLUSION

These results suggest that hepatic connexin43-based signaling may protect against acetaminophen-induced liver toxicity.

Connexin32: a mediator of acetaminophen-induced liver injury?

Connexin32 is the building block of hepatocellular gap junctions, which control direct intercellular communication and thereby act as goalkeepers of liver homeostasis. This study was set up to investigate whether connexin32 is involved in hepatotoxicity induced by the analgesic and antipyretic drug acetaminophen. To this end, whole body connexin32 knock-out mice were overdosed with acetaminophen followed by sampling at different time points within a 24-h time frame. Evaluation was done based upon a series of clinically and mechanistically relevant read-outs, including protein adduct formation, histopathological examination, measurement of alanine aminotransferase activity, cytokine production, levels of reduced and oxidized glutathione and hepatic protein amounts of proliferating cell nuclear antigen. In essence, it was found that genetic ablation of connexin32 has no influence on several key events in acetaminophen-induced hepatotoxicity, including cell death, inflammation or oxidative stress, yet it does affect production of protein adducts as well as proliferating cell nuclear antigen steady-state protein levels. This outcome is not in line with previous studies, which are contradicting on their own, as both amplification and alleviation of this toxicological process by connexin32 have been described. This could question the suitability of the currently available models and tools to investigate the role of connexin32 in acetaminophen-triggered hepatotoxicity.

The therapeutic effect of CORM-3 on acute liver failure induced by lipopolysaccharide/D-galactosamine in mice

BACKGROUND

Acute liver failure (ALF) is a severe and life-threatening clinical syndrome resulting in a high mortality and extremely poor prognosis. Recently, a water-soluble CO-releasing molecule (CORM-3) has been shown to have anti-inflammatory effect. The present study was to investigate the effect of CORM-3 on ALF and elucidate its underlying mechanism.

METHODS

ALF was induced by a combination of LPS/D-GalN in mice which were treated with CORM-3 or inactive CORM-3 (iCORM-3). The efficacy of CORM-3 was evaluated based on survival, liver histopathology, serum aminotransferase activities (ALT and AST) and total bilirubin (TBiL). Serum levels of inflammatory cytokines (TNF-alpha, IL-6, IL-1beta and IL-10) and liver immunohistochemistry of NF-kappaB-p65 were determined; the expression of inflammatory mediators such as iNOS, COX-2 and TLR4 was measured using Western blotting.

RESULTS

The pretreatment with CORM-3 significantly improved the liver histology and the survival rate of mice compared with the controls; CORM-3 also decreased the levels of ALT, AST and TBiL. Furthermore, CORM-3 significantly inhibited the increased concentration of pro-inflammatory cytokines (TNF-alpha, IL-6 and IL-1beta) and increased the anti-inflammatory cytokine (IL-10) productions in ALF mice. Moreover, CORM-3 significantly reduced the increased expression of iNOS and TLR4 in liver tissues and inhibited the nuclear expression of NF-kappaB-p65. CORM-3 had no effect on the increased expression of COX-2 in the ALF mice. An iCORM-3 failed to prevent acute liver damage induced by LPS/D-GalN.

CONCLUSION

These findings provided evidence that CORM-3 may offer a novel alternative approach for the management of ALF through anti-inflammatory functions.

Experimental models of hepatotoxicity related to acute liver failure

Acute liver failure can be the consequence of various etiologies, with most cases arising from drug-induced hepatotoxicity in Western countries. Despite advances in this field, the management of acute liver failure continues to be one of the most challenging problems in clinical medicine. The availability of adequate experimental models is of crucial importance to provide a better understanding of this condition and to allow identification of novel drug targets, testing the efficacy of new therapeutic interventions and acting as models for assessing mechanisms of toxicity. Experimental models of hepatotoxicity related to acute liver failure rely on surgical procedures, chemical exposure or viral infection. Each of these models has a number of strengths and weaknesses. This paper specifically reviews commonly used chemical in vivo and in vitro models of hepatotoxicity associated with acute liver failure.

Results of a fast-track referral system for urgent outpatient hepatology visits

OBJECTIVE

In 2011, our regional district adopted an experimental system for fast referral (within 72 h) by general practitioners to several outpatient specialist evaluations including hepatology. The aim of this study was to assess the characteristics and appropriateness of urgent hepatology visits.

DESIGN

Retrospective study.

SETTING

Hospital-based study in Italy.

PARTICIPANTS

A total of 192 subjects referred to our outpatient hepatology clinic classified as 'urgent' were compared with 397 patients evaluated with standard referral. A comparison with 200 patients visited just before the adoption of the new system was also included.

MAIN OUTCOME MEASURES

Patients' features and appropriateness of referral in urgent and non-urgent groups using the new system.

RESULTS

Increase in liver enzymes was the main factor that leads to specialist hepatology consultation and was more frequent in the urgent group (37% vs. 27.1%, P < 0.001). Liver malignancies were identified in 2.6% of patients in the urgent group, whereas this percentage was 10 times lower in the non-urgent group (P = 0.01). Urgent patients required inpatient admission more frequently compared with non-urgent patients (4.2% vs. 0.5%; P = 0.003). Inappropriate referral was recorded in 41% of cases in the urgent group (no reason for urgency 27%; condition not attributable to liver 13.5%). In the non-urgent group, consultations were inappropriate in 20.1% of cases (condition not attributable to liver). In comparison with the old system, the new one allocated >85% of patients with serious illness to urgent group.

CONCLUSIONS

This strategy is helpful in selecting patients with more serious hepatic conditions. Appropriateness of referral represents a crucial issue.

Update in intensive care medicine: acute liver failure. Initial management, supportive treatment and who to transplant

PURPOSE OF REVIEW

Acute liver failure (ALF) is associated with significant mortality. Although specific therapies may be available, the evidence base for these and for many aspects of supportive therapy has been slow to emerge. Liver transplantation continues to be a cornerstone of treatment, and the management of ALF, therefore, remains the domain of the specialist ICU. The purpose of this review is to identify and critically appraise the recent evidence and to inspire those who strive to provide excellent care for a difficult patient cohort.

RECENT FINDINGS

Effective vaccination programmes have reduced the incidence of viral hepatitis in Europe and the USA. Spontaneous survival has improved in causes such as acetaminophen toxicity. Early recognition and proactive intensive management have reduced the incidence of early neurological death. The use of artificial liver assist devices and therapeutic plasma exchange is controversial, yet intriguing, with some early evidence of efficacy.

SUMMARY

Increasingly sophisticated prognostication tools are evolving, which have the potential to transform clinical decision-making. A review of the indications for transplantation in acetaminophen toxicity is overdue. The use of therapeutic plasma exchange and extracorporeal liver support in ALF requires further investigation.

Emodin ameliorated lipopolysaccharide-induced fulminant hepatic failure by blockade of TLR4/MD2 complex expression in D-galactosamine-sensitized mice

Emodin has been reported to possess anti-inflammatory and anti-oxidant activities. The aim of this study was to explore the effect and mechanism of emodin on lipopolysaccharide (LPS)-induced fulminant hepatic failure (FHF) in D-galactosamine (D-GalN)-sensitized mice. Our results showed that pretreatment with emodin inhibited the elevation of plasma aminotransferases, alleviated the hepatic histopathological abnormalities and improved the survival rate of LPS/D-GalN-primed mice. Moreover, emodin markedly attenuated the increased serum and hepatic tumor necrosis factor-α (TNF-α) production, and activated hepatic p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signal pathways in LPS/D-GalN-challenged mice. Furthermore, using an in vitro experiment, we found that emodin dose-dependently suppressed TNF-α production, dampened AP-1 and NF-κB activation, and blocked toll-like receptor (TLR) 4/myeloid differentiation factor (MD) 2 complex expression in LPS-elicited RAW264.7 mouse macrophage cells. Taken together, these data suggested that emodin could effectively prevent LPS-induced FHF, which might be mediated by inhibition of TNF-α production, deactivation of MAPKs and NF-κB, and blockade of TLR4/MD2 complex expression.

Synthetic RGDS peptide attenuated lipopolysaccharide/D-galactosamine-induced fulminant hepatic failure in mice

BACKGROUND AND AIM

Fulminant hepatic failure (FHF) is a serious clinic syndrome with extremely poor prognosis and no effective treatment except for liver transplantation. Synthetic RGDS peptide, an inhibitor of integrins, was proved to suppress integrin signals. In this study, we investigated the protection effects of RGDS peptide on lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced FHF and the underlying molecular mechanisms.

METHODS

Synthetic RGDS peptide was given intraperitoneally 30 min before LPS/D-GalN injection. Liver function and the extent of liver injury were analyzed biochemically and pathologically respectively. Enzyme-linked immunosorbent assay, real-time polymerase chain reaction and Western blotting were used to detect effectors and signaling molecules.

RESULTS

Pretreatment with synthetic RGDS peptide significantly improved LPS/D-GalN-induced mortality, and liver injury as determined by alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, as well as pathological analysis. In addition, RGDS peptide significantly reduced tumor necrosis factor (TNF)-α and macrophage inflammatory protein (MIP)-2 production, and decreased myeloperoxidase (MPO) and NF-κB activity. Furthermore, Western blotting indicated that the levels of phospho-integrin β3, phospho-focal adhesion kinase (FAK) and phospho-p38 mitogen-activated protein kinases (MAPK) decreased with RGDS peptide pretreatment.

CONCLUSION

Together, these data suggest that synthetic RGDS peptide protect against LPS/D-GalN-induced FHF by inhibiting inflammatory cells migration and blocking the integrin αVβ3-FAK-p38 MAPK and NF-κB signaling.

Autophagy in drug-induced liver toxicity

Liver injury resulting from exposure to drugs and chemicals is a major health problem. Autophagy is an important factor in a wide range of diseases, such as cancer, liver disease, muscular disorder, neurodegeneration, pathogen infection, and aging, and emerging evidence indicates that autophagy makes a substantial contribution to the pathogenesis of drug- and chemical-induced liver toxicity. In this review, we summarize current knowledge on autophagy triggered by toxicants/toxins, the protective role of autophagy in liver toxicity, and the underlying molecular mechanisms. We also highlight experimental approaches for studying autophagy.

Long term results of liver transplantation for Wilson's disease: experience in France

BACKGROUND & AIMS

Liver transplantation (LT) is the therapeutic option for severe complications of Wilson's disease (WD). We aimed to report on the long-term outcome of WD patients following LT.

METHODS

The medical records of 121 French patients transplanted for WD between 1985 and 2009 were reviewed retrospectively. Seventy-five patients were adults (median age: 29 years, (18-66)) and 46 were children (median age: 14 years, (7-17)). The indication for LT was (1) fulminant/subfulminant hepatitis (n = 64, 53%), median age = 16 years (7-53), (2) decompensated cirrhosis (n = 50, 41%), median age = 31.5 years (12-66) or (3) severe neurological disease (n = 7, 6%), median age = 21.5 years (14.5-42). Median post-transplant follow-up was 72 months (0-23.5).

RESULTS

Actuarial patient survival rates were 87% at 5, 10, and 15 years. Male gender, pre-transplant renal insufficiency, non elective procedure, and neurological indication were significantly associated with poorer survival rate. None of these factors remained statistically significant under multivariate analysis. In patients transplanted for hepatic indications, the prognosis was poorer in case of fulminant or subfulminant course, non elective procedure, pretransplant renal insufficiency and in patients transplanted before 2000. Multivariate analysis disclosed that only recent period of LT was associated with better prognosis. At last visit, the median calculated glomerular filtration rate was 93 ml/min (33-180); 11/93 patients (12%) had stage II renal insufficiency and none had stage III.

CONCLUSIONS

Liver failure associated with WD is a rare indication for LT (<1%), which achieves an excellent long-term outcome, including renal function.

Causes and outcomes of acute liver failure in China

Objectives

No extensive investigation has been performed and thus no representative data are available regarding acute liver failure (ALF) in China. This study aims to investigate the causes and outcomes of ALF in China and establish a prognostic model.

Methods

Patients diagnosed as ALF in seven hospitals in different areas of China from January 2007 to December 2012 were retrospectively selected.

Results

Of the 177 patients included in this study, 112 (63.28%) eventually died. The common causes of ALF were drug toxicity (43.50%), indeterminate etiology (29.38%) and acute viral hepatitis (11.30%). Additionally, traditional Chinese herbs predominated in the causes of drug-induced ALF (30/77). No patients in this study received liver transplantation. In the established model for predicting death in ALF, four variables were finally selected out, including age (P=0.01), the entry hepatic encephalopathy grade (P=0.04), international normalized ratio (P<0.01) and arterial blood ammonia (P=0.02). Using a threshold value of 0.5683, this model had a sensitivity of 95.24% and a specificity of 91.30%.

Conclusions

Traditional Chinese medicine was a major cause of ALF in China. The spontaneous mortality of ALF was high, whereas the rate of liver transplantation was significantly low. The established prognostic model of ALF had superior sensitivity and specificity.

A new style of dimethylnitrosamine induced fulminant hepatitis in mice

BACKGROUND

There is still no suitable mice model that can completely mimic the human fulminant hepatitis, which sets a block for drug effect evaluation and mechanism researching of human fulminant hepatitis.

OBJECTIVES

The aim of this study was to establish an animal model able to mimic the main features of human fulminant hepatitis.

MATERIALS AND METHODS

Dimethylnitrosamine (DMN) was peritoneally injected to mice for liver injury induction. Serum biochemicals, and Prothrombin Time were tested, and Prothrombin activity was calculated, the liver tissue pathological changes were evaluated via macroscopic view observation, HE staining, immunochemical staining, and electron microscopy observation. The mRNA levels of TNF-a, Fas, and IL-1beta were tested with quantitative PCR assay.

RESULTS

The serum levels of both ALT and AST were elevated significantly and showed a high plateau. Liver pathological changes were progressed before 48 hours post DMN injection and then started to restore. The mRNA and protein expression levels of TNF-α and IL-1β were significantly elevated. The PT started to extend from 36 hours and PTA was lower than 40% from then on.

CONCLUSIONS

This kind of DMN induced mice liver injury is similar to human fulminant hepatitis in main features. This work provided a mice model which could mimic human fulminant hepatitis, and could be valuable for fulminant hepatitis mechanism research and liver protection drug evaluation.

Role of toll-like receptor 4 in mediating multiorgan dysfunction in mice with acetaminophen induced acute liver failure

Strategies for the prevention of multiorgan dysfunction (MOD) in acetaminophen (APAP)-induced acute liver failure (ALF) are an unmet need. Our study tested the hypothesis that sterile inflammation induced by APAP in a mouse model would activate toll-like receptor 4 (TLR4) in the liver and extrahepatic organs and lead to the progression of ALF and MOD and that the administration of the novel TLR4 antagonist STM28 (a peptide formed of 17 amino-acids) would prevent liver injury and associated MOD. ALF and, subsequently, MOD were induced in TLR4-knockout (KO) mice (B6.B10ScN-Tlr4 (lpsdel) /JthJ) and wild-type (WT) mice (C57BL/6) with APAP (500 mg/kg). A second set of experiments was conducted to evaluate the effects of a pretreatment with a novel TLR4 antagonist, STM28, on APAP-induced MOD in CD1 mice. Animals were sacrificed at the coma stage, and plasma, peripheral blood cells, liver, kidneys, and brain were collected. Biochemistry values and cytokines were measured. Liver and kidneys were studied histologically and were stained for TLR4 and activated Kupffer cells, and the expression of nuclear factor kappa B-p65 was quantified with western blotting. Brain water was measured in the frontal cortex. After APAP administration, TLR4-KO (NFkBp65) mice were relatively protected from liver necrosis and end-organ dysfunction and had significantly better survival than WT controls (P < 0.01). STM28 attenuated liver injury and necrosis, reduced creatinine levels, and delayed the time to a coma significantly. The increases in cytokines in the plasma and liver, including TLR4 expression and the activation of Kupffer cells, after APAP administration were reduced significantly in the STM28-treated animals. The increased number of circulating myeloid cells was reduced significantly after STM28 treatment. In conclusion, these data provide evidence for an important role of the TLR4 antagonist in the prevention of the progression of APAP-induced ALF and MOD.

Circulating microRNAs: promising candidates serving as novel biomarkers of acute hepatitis

Acute liver failure as life threatening condition comprises a difficult diagnostic situation to evaluate potential outcomes and therapeutic options. Thus, prognostic indicators are urgently needed for evaluation of progression of liver injury, clinical outcome, prognosis, and for therapeutic response. Recently, circulating microRNA, in particular miR-122, was described as a potential biomarker of acute liver injury after intoxication of mice. Circulating microRNA (miRNA) molecules are very stable and RNase-resistant due to protein aggregation and vesicle enclosure. Since miRNA species are known to be associated with chronic liver damage or with liver cancer, circulating miRNA patterns are suggested to serve also as reporters for progression of acute liver failure. miRNA profiling analyses using PCR arrays or next generation sequencing, may achieve identification of miRNA species that are linked to the rapid progression of acute liver injury, to the outcome of liver failure, or to the therapeutic response. Therefore, circulating miRNAs are promising, non-invasive biomarkers of future diagnostic approaches. However, normalisation of circulating miRNA levels is essential and further standardisation of miRNA quantification assays is needed.

Liver transplantation for acute liver failure in Europe: outcomes over 20 years from the ELTR database

BACKGROUND & AIMS

Liver transplantation for acute liver failure (ALF) still has a high early mortality. We evaluated changes during 20 years, and identified risk factors for poor outcome.

METHODS

Donor, graft, and recipient variables from the European Liver Transplant Registry database (January 1988-June 2009), were analysed. Aetiologies and time periods were compared. Three and 12-month survival models were generated from separate training data sets, which were validated. A sub-analysis was performed for recipient older than 50 years.

RESULTS

Four thousand nine hundred and three patients were evaluated. One, 5- and 10-year patient, and graft survival rates were 74%, 68%, 63%, and 63%, 57%, 50%, respectively. Survival was better in 2004-2009 compared to previous quinquennia (p<0.001), despite donors >60 years increased from 1.8% to 21%. A higher incidence of suicide or non-adherence occurred in paracetamol-related ALF (p<0.001). Death or graft loss were independently associated with male recipients (adjusted OR 1.25), recipient >50 years (1.26), incompatible ABO matching (1.93), donors >60 years (1.21), and reduced size graft (1.54). For both 3- and 12-month models, incompatible ABO matching, non-viral aetiology, reduced size graft, and non-UW preservation fluid were associated with increased mortality/graft loss, whereas male recipients and age >50 years were associated only at 12 months. Both models had reasonable discriminative ability with good calibration at 3 months. Recipients >50 years, combined with donors >60 years resulted in 57% mortality/graft loss within the first year.

CONCLUSIONS

Survival after liver transplantation has improved despite increases in donor/recipient age. Recipients >50 years paired with donors >60 years had a very high mortality/graft loss within the first year.