Serum aryl hydrocarbon receptor activity is associated with survival in patients with alcohol-associated hepatitis.

BACKGROUND AND AIMS: Patients with alcohol-associated hepatitis (AH) have an altered fecal metabolome, including reduced microbiota-derived tryptophan metabolites, which function as ligands for aryl hydrocarbon receptor (AhR). The aim of this study was to assess serum AhR ligand activity in patients with AH. APPROACH AND RESULTS: The study included 74 controls without AUD, 97 patients with AUD, and 330 patients with AH from 2 different multicenter cohorts (InTeam: 134, AlcHepNet: 196). Serum AhR activity was evaluated using an AhR reporter assay with HepG2-Lucia cells incubated with serum for 24 hours. Serum AhR activity was significantly higher in patients with AH compared with both controls (1.59 vs. 0.96-fold change, p < 0.001) and patients with AUD (1.59 vs. 0.93, p < 0.001). In both AH cohorts, patients with AhR activity ≥ 2.09 had significantly lower cumulative survival rates at 30, 60, 90, and 180 days compared to those with AhR activity < 2.09. When serum AhR activity was used to further stratify patients with severe AH, the cumulative 30, 60, 90, and 180-day survival rates for patients with severe AH and the AhR activity ≥ 2.09 group were all significantly lower than those with an AhR activity < 2.09 group. CONCLUSIONS: Serum AhR activity was significantly higher in patients with AH compared with controls and individuals with AUD, and this increased activity was associated with higher mortality. Consequently, serum AhR activity holds potential as a prognostic marker.

Recurrent alcohol-associated hepatitis is common and is associated with increased mortality.

BACKGROUND AND AIMS: Alcohol relapse after surviving an episode of alcohol-associated hepatitis (AH) is common. However, the clinical features, risk factors, and prognostic implications of recurrent alcohol-associated hepatitis (RAH) are not well described. APPROACH AND RESULTS: A registry-based study was done of patients admitted to 28 Spanish hospitals for an episode of AH between 2014 and 2021. Baseline demographics and laboratory variables were collected. Risk factors for RAH were investigated using Cox regression analysis. We analyzed the severity of the index episodes of AH and compared it to that of RAH. Long-term survival was assessed by Kaplan-Meier curves and log-rank tests. A total of 1118 patients were included in the analysis, 125 (11%) of whom developed RAH during follow-up (median: 17 [7-36] months). The incidence of RAH in patients resuming alcohol use was 22%. The median time to recurrence was 14 (8-29) months. Patients with RAH had more psychiatric comorbidities. Risk factors for developing RAH included age <50 years, alcohol use >10 U/d, and history of liver decompensation. RAH was clinically more severe compared to the first AH (higher MELD, more frequent ACLF, and HE). Moreover, alcohol abstinence during follow-up was less common after RAH (18% vs. 45%, p <0.001). Most importantly, long-term mortality was higher in patients who developed RAH (39% vs. 21%, p = 0.026), and presenting with RAH independently predicted high mortality (HR: 1.55 [1.11-2.18]). CONCLUSIONS: RAH is common and has a more aggressive clinical course, including increased mortality. Patients surviving an episode of AH should undergo intense alcohol use disorder therapy to prevent RAH.

Bacteriophage targeting of gut bacterium attenuates alcoholic liver disease.

Chronic liver disease due to alcohol-use disorder contributes markedly to the global burden of disease and mortality1-3. Alcoholic hepatitis is a severe and life-threatening form of alcohol-associated liver disease. The gut microbiota promotes ethanol-induced liver disease in mice4, but little is known about the microbial factors that are responsible for this process. Here we identify cytolysin-a two-subunit exotoxin that is secreted by Enterococcus faecalis5,6-as a cause of hepatocyte death and liver injury. Compared with non-alcoholic individuals or patients with alcohol-use disorder, patients with alcoholic hepatitis have increased faecal numbers of E. faecalis. The presence of cytolysin-positive (cytolytic) E. faecalis correlated with the severity of liver disease and with mortality in patients with alcoholic hepatitis. Using humanized mice that were colonized with bacteria from the faeces of patients with alcoholic hepatitis, we investigated the therapeutic effects of bacteriophages that target cytolytic E. faecalis. We found that these bacteriophages decrease cytolysin in the liver and abolish ethanol-induced liver disease in humanized mice. Our findings link cytolytic E. faecalis with more severe clinical outcomes and increased mortality in patients with alcoholic hepatitis. We show that bacteriophages can specifically target cytolytic E. faecalis, which provides a method for precisely editing the intestinal microbiota. A clinical trial with a larger cohort is required to validate the relevance of our findings in humans, and to test whether this therapeutic approach is effective for patients with alcoholic hepatitis.

Clinical, histological and molecular profiling of different stages of alcohol-related liver disease.

OBJECTIVE: Alcohol-related liver disease (ALD) ranges from never-decompensated ALD (ndALD) to the life-threatening decompensated phenotype, known as alcohol-related hepatitis (AH). A multidimensional study of the clinical, histological and molecular features of these subtypes is lacking. DESIGN: Two large cohorts of patients were recruited in an international, observational multicentre study: a retrospective cohort of patients with ndALD (n=110) and a prospective cohort of patients with AH (n=225). Clinical, analytical, immunohistochemistry and hepatic RNA microarray analysis of both disease phenotypes were performed. RESULTS: Age and mean alcohol intake were similar in both groups. AH patients had greater aspartate amino transferase/alanine amino transferase ratio and lower gamma-glutamyl transferase levels than in ndALD patients. Patients with AH demonstrated profound liver failure and increased mortality. One-year mortality was 10% in ndALD and 50% in AH. Histologically, steatosis grade, ballooning and pericellular fibrosis were similar in both groups, while advanced fibrosis, Mallory-Denk bodies, bilirubinostasis, severe neutrophil infiltration and ductular reaction were more frequent among AH patients. Transcriptome analysis revealed a profound gene dysregulation within both phenotypes when compare to controls. While ndALD was characterised by deregulated expression of genes involved in matrisome and immune response, the development of AH resulted in a marked deregulation of genes involved in hepatocyte reprogramming and bile acid metabolism. CONCLUSIONS: Despite comparable alcohol intake, AH patients presented with worse liver function compared with ndALD patients. Bilirubinostasis, severe fibrosis and ductular reaction were prominent features of AH. AH patients exhibited a more profound deregulation of gene expression compared with ndALD patients.

Integrated Multiomics Reveals Glucose Use Reprogramming and Identifies a Novel Hexokinase in Alcoholic Hepatitis.

BACKGROUND & AIMS: We recently showed that alcoholic hepatitis (AH) is characterized by dedifferentiation of hepatocytes and loss of mature functions. Glucose metabolism is tightly regulated in healthy hepatocytes. We hypothesize that AH may lead to metabolic reprogramming of the liver, including dysregulation of glucose metabolism. METHODS: We performed integrated metabolomic and transcriptomic analyses of liver tissue from patients with AH or alcoholic cirrhosis or normal liver tissue from hepatic resection. Focused analyses of chromatin immunoprecipitation coupled to DNA sequencing was performed. Functional in vitro studies were performed in primary rat and human hepatocytes and HepG2 cells. RESULTS: Patients with AH exhibited specific changes in the levels of intermediates of glycolysis/gluconeogenesis, the tricarboxylic acid cycle, and monosaccharide and disaccharide metabolism. Integrated analysis of the transcriptome and metabolome showed the used of alternate energetic pathways, metabolite sinks and bottlenecks, and dysregulated glucose storage in patients with AH. Among genes involved in glucose metabolism, hexokinase domain containing 1 (HKDC1) was identified as the most up-regulated kinase in patients with AH. Histone active promoter and enhancer markers were increased in the HKDC1 genomic region. High HKDC1 levels were associated with the development of acute kidney injury and decreased survival. Increased HKDC1 activity contributed to the accumulation of glucose-6-P and glycogen in primary rat hepatocytes. CONCLUSIONS: Altered metabolite levels and messenger RNA expression of metabolic enzymes suggest the existence of extensive reprogramming of glucose metabolism in AH. Increased HKDC1 expression may contribute to dysregulated glucose metabolism and represents a novel biomarker and therapeutic target for AH.

Effect of rifaximin on infections, acute-on-chronic liver failure and mortality in alcoholic hepatitis: A pilot study (RIFA-AH).

BACKGROUND & AIMS: Alcoholic hepatitis (AH) is associated with a high incidence of infection and mortality. Rifaximin reduces bacterial overgrowth and translocation. We aimed to study whether the administration of rifaximin as an adjuvant treatment to corticosteroids decreases the number of bacterial infections at 90 days in patients with severe AH compared to a control cohort. METHODS: This was a multicentre, open, comparative pilot study of the addition of rifaximin (1200 mg/day/90 days) to the standard treatment for severe AH. The results were compared with a carefully matched historical cohort of patients treated with standard therapy and matching by age and model of end-stage liver disease (MELD). We evaluated bacterial infections, liver-related complications, mortality and liver function tests after 90 days. RESULTS: Twenty-one and 42 patients were included in the rifaximin and control groups respectively. No significant baseline differences were found between groups. The mean number of infections per patient was 0.29 and 0.62 in the rifaximin and control groups, respectively (p = .049), with a lower incidence of acute-on-chronic liver failure (ACLF) linked to infections within the treatment group. Liver-related complications were lower within the rifaximin group (0.43 vs. 1.26 complications/patient respectively) (p = .01). Mortality was lower in the treated versus the control groups (14.2% vs. 30.9, p = .15) without significant differences. No serious adverse events were associated with rifaximin treatment. CONCLUSIONS: Rifaximin is safe in severe AH with a significant reduction in clinical complications. A lower number of infections and a trend towards a lower ACLF and mortality favours its use in these patients.

The Level of Alcohol Consumption in the Prior Year Does Not Impact Clinical Outcomes in Patients With Alcohol-Associated Hepatitis.

The 10-item Alcohol Use Disorders Identification Test (AUDIT-10) and its shorter form, AUDIT-Consumption (AUDIT-C), are questionnaires used to characterize severity of drinking. We hypothesized that liver injury and short-term outcomes of alcohol-associated hepatitis (AH) would correlate with a patient's recent alcohol consumption as determined by AUDIT-10 and AUDIT-C. We analyzed a prospective international database of patients with AH diagnosed based on the National Institute on Alcohol Abuse and Alcoholism (NIAAA) standard definitions. All patients were interviewed using AUDIT-10. Primary outcomes included the discriminatory ability of the AUDIT-10 and AUDIT-C scores for predicting survival status at 28 and 90 days and severity of liver injury, as measured by Model for End-Stage Liver Disease-sodium (MELD-Na). The relationship between AUDIT scores and survival status was quantified by calculating the area under the curve of the receiver operating characteristic analysis. The relationship between AUDIT scores and MELD-Na was examined using correlation coefficients. In 245 patients (age range 25-75 years; 35% female), we found no correlation between AUDIT-10 or AUDIT-C scores and either 28- or 90-day mortality. Similarly, there was no correlation between AUDIT-10 and AUDIT-C and MELD-Na scores. There was a strong positive correlation between MELD-Na and 28- and 90-day mortality. Additional measures of severity of alcohol use (average grams of alcohol consumed per day, years of drinking, convictions for driving under the influence, and rehabilitation attempts) and psychosocial factors (marriage, paid employment, and level of social support) had no influence on MELD-Na. In patients presenting with AH, AUDIT-10 and AUDIT-C were predictors of neither clinical severity of liver disease nor short-term mortality, suggesting that level of alcohol consumption in the prior year is not key to the presenting features or outcome of AH.

Intestinal Fungal Dysbiosis and Systemic Immune Response to Fungi in Patients With Alcoholic Hepatitis.

Chronic alcohol consumption causes increased intestinal permeability and changes in the intestinal microbiota composition, which contribute to the development and progression of alcohol-related liver disease. In this setting, little is known about commensal fungi in the gut. We studied the intestinal mycobiota in a cohort of patients with alcoholic hepatitis, patients with alcohol use disorder, and nonalcoholic controls using fungal-specific internal transcribed spacer amplicon sequencing of fecal samples. We further measured serum anti-Saccharomyces cerevisiae antibodies (ASCA) as a systemic immune response to fungal products or fungi. Candida was the most abundant genus in the fecal mycobiota of the two alcohol groups, whereas genus Penicillium dominated the mycobiome of nonalcoholic controls. We observed a lower diversity in the alcohol groups compared with controls. Antibiotic or steroid treatment was not associated with a lower diversity. Patients with alcoholic hepatitis had significantly higher ASCA levels compared to patients with alcohol use disorder and to nonalcoholic controls. Within the alcoholic hepatitis cohort, patients with levels of at least 34 IU/mL had a significantly lower 90-day survival (59%) compared with those with ASCA levels less than 34 IU/mL (80%) with an adjusted hazard ratio of 3.13 (95% CI, 1.11-8.82; P = 0.031). Conclusion: Patients with alcohol-associated liver disease have a lower fungal diversity with an overgrowth of Candida compared with controls. Higher serum ASCA was associated with increased mortality in patients with alcoholic hepatitis. Intestinal fungi may serve as a therapeutic target to improve survival, and ASCA may be useful to predict the outcome in patients with alcoholic hepatitis.

Intestinal Virome in Patients With Alcoholic Hepatitis.

BACKGROUND AND AIMS: Alcoholic hepatitis (AH) is a severe manifestation of alcohol-associated liver disease (ALD) with high mortality. Although gut bacteria and fungi modulate disease severity, little is known about the effects of the viral microbiome (virome) in patients with ALD. APPROACH AND RESULTS: We extracted virus-like particles from 89 patients with AH who were enrolled in a multicenter observational study, 36 with alcohol use disorder (AUD), and 17 persons without AUD (controls). Virus-like particles from fecal samples were fractionated using differential filtration techniques, and metagenomic sequencing was performed to characterize intestinal viromes. We observed an increased viral diversity in fecal samples from patients with ALD, with the most significant changes in samples from patients with AH. Escherichia-, Enterobacteria-, and Enterococcus phages were over-represented in fecal samples from patients with AH, along with significant increases in mammalian viruses such as Parvoviridae and Herpesviridae. Antibiotic treatment was associated with higher viral diversity. Specific viral taxa, such as Staphylococcus phages and Herpesviridae, were associated with increased disease severity, indicated by a higher median Model for End-Stage Liver Disease score, and associated with increased 90-day mortality. CONCLUSIONS: In conclusion, intestinal viral taxa are altered in fecal samples from patients with AH and associated with disease severity and mortality. Our study describes an intestinal virome signature associated with AH.

Perturbations in Mitochondrial Dynamics Are Closely Involved in the Progression of Alcoholic Liver Disease.

BACKGROUND: Mitochondria play a fundamental role in the pathogenesis of alcoholic liver disease (ALD). The preservation of functional mitochondria during toxic alcohol insults is essential for cell survival and is maintained by key processes known as mitochondrial dynamics, including fragmentation and fusion, which are regulated by mitochondria-shaping proteins (MSP). We have shown mitochondrial dynamics to be distorted by alcohol in cellular and animal models, but the effect in humans remains unknown. METHODS: Hepatic gene expression of the main MSP involved in the mitochondrial fusion and fragmentation pathways was evaluated in patients with alcoholic hepatitis (AH) by DNA microarray (n = 15) and Reverse Transcription Polymerase Chain Reaction (n = 32). The activation of dynamin-1-like protein (Drp1) was also investigated in mitochondria isolated from liver biopsies of ALD patients (n = 8). The effects of alcohol on mitochondrial dynamics and on MSP protein expression were studied in human precision-cut liver slices (PCLS) exposed for 24 hours to increasing doses of ethanol (EtOH; 50 to 250 mM). RESULTS: A profound hyperactivation of the fragmentation pathway was observed in AH patients, with a significant increase in the expression of Drp1 and its adapters/receptors. The translocation of Drp1 to the mitochondria was also induced in patients with severe ALD and was affected in the PCLS with short-term exposure to EtOH but only mildly. The fusion pathway was not altered in ALD, and this was confirmed in the PCLS model. CONCLUSIONS: The present study reveals the role of mitochondrial dynamics in human ALD, confirming our previous observations in animal and cell culture models of ALD. Taken together, we show that alcohol has a significant impact on the fragmentation pathway, and we confirm Drp1 as a potential therapeutic target in severe ALD.

Expression of microRNA-155 in inflammatory cells modulates liver injury.

MicroRNA 155 (miR-155) is involved in immune and inflammatory diseases and is associated with liver fibrosis and steatohepatitis. However, the mechanisms involved in miR-155 regulation of liver injury are largely unknown. The role of miR-155 in acute liver injury was assessed in wild-type (WT), miR-155-/- , and miR-155-/- mice transplanted with WT bone marrow. Additionally, miR-155 expression was evaluated in liver tissue and peripheral blood mononuclear cells of patients with autoimmune hepatitis. Concanavalin A, but not acetaminophen, treatment increased the expression of miR-155 in liver tissue of WT mice. Concanavalin A induced increases in cell death, liver aminotransferases, and expression of proinflammatory cytokines (chemokine [C-X-C motif] ligands 1, 5, 9, 10, and 11; chemokine [C-C motif] ligands 2 and 20; and intercellular cell adhesion molecule 1) in miR-155-/- compared to WT mice. Importantly, these animals showed a significant decrease in cluster of differentiation 4-positive/chemokine (C-X-C motif) receptor 3-positive and forkhead box p3-positive cell recruitment but no changes in other inflammatory cell populations. Mechanistically, miR-155-deficient regulatory T cells showed increased SH2 domain-containing inositol 5-phosphatase 1 expression, a known target of miR-155. Inhibition of SH2 domain-containing inositol 5-phosphatase 1 in miR-155-/- mice restored forkhead box p3 recruitment and reduced liver cytokine expression. Transplantation of bone marrow from WT animals into miR-155-/- mice partially reversed the effect of concanavalin A on miR-155-/- mice as assessed by proinflammatory cytokines and cell death protein expression. Patients with autoimmune hepatitis showed a marked increase in miR-155 expression in the liver but reduced expression of miR-155 in peripheral blood mononuclear cells. CONCLUSION: miR-155 expression is altered in both liver tissue and circulating inflammatory cells during liver injury, thus regulating inflammatory cell recruitment and liver damage; these results suggest that maintaining miR-155 expression in inflammatory cells might be a potential strategy to modulate liver injury. (Hepatology 2018).

A randomized, placebo-controlled trial of cenicriviroc for treatment of nonalcoholic steatohepatitis with fibrosis.

The aim of this study was to evaluate cenicriviroc (CVC), a dual antagonist of CC chemokine receptor types 2 and 5, for treatment of nonalcoholic steatohepatitis (NASH) with liver fibrosis (LF). A randomized, double-blind, multinational phase 2b study enrolled subjects with NASH, a nonalcoholic fatty liver disease activity score (NAS) ≥4, and LF (stages 1-3, NASH Clinical Research Network) at 81 clinical sites. Subjects (N = 289) were randomly assigned CVC 150 mg or placebo. Primary outcome was ≥2-point improvement in NAS and no worsening of fibrosis at year 1. Key secondary outcomes were: resolution of steatohepatitis (SH) and no worsening of fibrosis; improvement in fibrosis by ≥1 stage and no worsening of SH. Biomarkers of inflammation and adverse events were assessed. Full study recruitment was achieved. The primary endpoint of NAS improvement in the intent-to-treat population and resolution of SH was achieved in a similar proportion of subjects on CVC (N = 145) and placebo (N = 144; 16% vs. 19%, P = 0.52 and 8% vs. 6%, P = 0.49, respectively). However, the fibrosis endpoint was met in significantly more subjects on CVC than placebo (20% vs. 10%; P = 0.02). Treatment benefits were greater in those with higher disease activity and fibrosis stage at baseline. Biomarkers of systemic inflammation were reduced with CVC. Safety and tolerability of CVC were comparable to placebo. CONCLUSION: After 1 year of CVC treatment, twice as many subjects achieved improvement in fibrosis and no worsening of SH compared with placebo. Given the urgent need to develop antifibrotic therapies in NASH, these findings warrant phase 3 evaluation. (Hepatology 2018;67:1754-1767).

Metabolomics Discloses a New Non-invasive Method for the Diagnosis and Prognosis of Patients with Alcoholic Hepatitis.

INTRODUCTION AND AIMS: Alcoholic hepatitis is the most severe manifestation of alcoholic liver disease. Unfortunately, there are still some unresolved issues in the diagnosis and management of this disease, such as the need of histological diagnosis, an accurate prognostic stratification, and the development of novel targeted therapies. The present study aimed at addressing these issues by means of metabolomics, a novel high-throughput approach useful in other liver diseases. MATERIAL AND METHODS: 64 patients with biopsy-proven alcoholic hepatitis were included and compared with 26 patients with decompensated alcoholic cirrhosis without superimposed alcoholic hepatitis, which was ruled out by liver biopsy. RESULTS: The comparison of the metabolic profiles of patients with alcoholic hepatitis and decompensated cirrhosis showed marked differences between both groups. Importantly, metabolic differences were found among alcoholic hepatitis patients when subjects were stratified according to 90-day survival. Based on these findings, two non-invasive signatures were developed. The first one allowed an accurate non-invasive diagnosis of alcoholic hepatitis (AUROC 0.932; 95% CI 0.901-0.963). The second signature showed a good performance in the prognostic stratification of patients with alcoholic hepatitis (AUROC 0.963; 95% CI 0.895-1.000). CONCLUSIONS: Signatures based on metabolomics allowed an accurate non-invasive diagnosis and prognostic stratification of alcoholic hepatitis. The differences observed in the metabolic profile of the patients according to the presence and severity of alcoholic hepatitis are related with different mechanisms involved in the pathophysiology of alcoholic hepatitis such as peroxisomal activity, synthesis of inflammatory mediators or oxidation. This information could be useful for the development of novel targeted therapies.

Alcohol-related liver disease. Clinical practice guidelines. Consensus document sponsored by AEEH. / Enfermedad hepática por alcohol. Guías de práctica clínica. Documento de consenso auspiciado por la AEEH.

Alcohol-related liver disease (ARLD) is the most prevalent cause of advanced liver disease and liver cirrhosis in Europe, including Spain. According to the World Health Organization the fraction of liver cirrhosis attributable to alcohol use in Spain is 73.8% among men and 56.3% among women. ARLD includes various stages such as steatohepatitis, cirrhosis and hepatocellular cancer. In addition, patients with underlying ARLD and heavy alcohol intake may develop alcoholic hepatitis, which is associated with high mortality. To date, the only effective treatment to treat ARLD is prolonged withdrawal. There are no specific treatments, and the only treatment that increases life expectancy in alcoholic hepatitis is prednisolone. For patients with alcoholic hepatitis who do not respond to treatment, some centres offer the possibility of an early transplant. These clinical practice guidelines aim to propose recommendations on ARLD taking into account their relevance as a cause of advanced chronic liver disease and liver cirrhosis in our setting. This paper aims to answer the key questions for the clinical practice of Gastroenterology, Hepatology, as well as Internal Medicine and Primary Health Centres, making the most up-to-date information regarding the management and treatment of ARLD available to health professionals. These guidelines provide evidence-based recommendations for the clinical management of this disease.

Dysregulation of serum bile acids and FGF19 in alcoholic hepatitis.

BACKGROUND & AIMS: The degree of cholestasis is an important disease driver in alcoholic hepatitis, a severe clinical condition that needs new biomarkers and targeted therapies. We aimed to identify the largely unknown mechanisms and biomarkers linked to cholestasis in alcoholic hepatitis. METHODS: Herein, we analyzed a well characterized cohort of patients with alcoholic hepatitis and correlated clinical and histological parameters and outcomes with serum bile acids and fibroblast growth factor 19 (FGF19), a major regulator of bile acid synthesis. RESULTS: We found that total and conjugated bile acids were significantly increased in patients with alcoholic hepatitis compared with controls. Serum FGF19 levels were strongly increased and gene expression of FGF19 was induced in biliary epithelial cells and ductular cells of patients with alcoholic hepatitis. De novo bile acid synthesis (CYP7A1 gene expression and C4 serum levels) was significantly decreased in patients with alcoholic hepatitis. Importantly, total and conjugated bile acids correlated positively with FGF19 and with disease severity (model for end-stage liver disease score). FGF19 correlated best with conjugated cholic acid, and model for end-stage liver disease score best with taurine-conjugated chenodeoxycholic acid. Univariate analysis demonstrated significant associations between FGF19 and bilirubin as well as gamma glutamyl transferase, and negative correlations between FGF19 and fibrosis stage as well as polymorphonuclear leukocyte infiltration, in all patients with alcoholic hepatitis. CONCLUSION: Serum FGF19 and bile acids are significantly increased in patients with alcoholic hepatitis, while de novo bile acid synthesis is suppressed. Modulation of bile acid metabolism or signaling could represent a promising target for treatment of alcoholic hepatitis in humans. LAY SUMMARY: Understanding the underlying mechanisms that drive alcoholic hepatitis is important for the development of new biomarkers and targeted therapies. Herein, we describe a molecule that is increased in patients with alcoholic hepatitis. Modulating the molecular pathway of this molecule might lead to promising targets for the treatment of alcoholic hepatitis.

Complement Factor D protects mice from ethanol-induced inflammation and liver injury.

Complement plays a crucial role in microbial defense and clearance of apoptotic cells. Emerging evidence suggests complement is an important contributor to alcoholic liver disease. While complement component 1, Q subcomponent (C1q)-dependent complement activation contributes to ethanol-induced liver injury, the role of the alternative pathway in ethanol-induced injury is unknown. Activation of complement via the classical and alternative pathways was detected in alcoholic hepatitis patients. Female C57BL/6J [wild type (WT)], C1q-deficient ( C1qa-/-, lacking classical pathway activation), complement protein 4-deficient ( C4-/-, lacking classical and lectin pathway activation), complement factor D-deficient ( FD-/-, lacking alternative pathway activation), and C1qa/FD-/- (lacking classical and alternative pathway activation) mice were fed an ethanol-containing liquid diet or pair-fed control diet for 4 or 25 days. Following chronic ethanol exposure, liver injury, steatosis, and proinflammatory cytokine expression were increased in WT but not C1qa-/-, C4-/-, or C1qa/FD-/- mice. In contrast, liver injury, steatosis, and proinflammatory mediators were robustly increased in ethanol-fed FD-/- mice compared with WT mice. Complement activation, assessed by hepatic accumulation of C1q and complement protein 3 (C3) cleavage products (C3b/iC3b/C3c), was evident in livers of WT mice in response to both short-term and chronic ethanol. While C1q accumulated in ethanol-fed FD-/- mice (short term and chronic), C3 cleavage products were detected after short-term but not chronic ethanol. Consistent with impaired complement activation, chronic ethanol induced the accumulation of apoptotic cells and fibrogenic responses in the liver of FD-/- mice. These data highlight the protective role of complement factor D (FD) and suggest that FD-dependent amplification of complement is an adaptive response that promotes hepatic healing and recovery in response to chronic ethanol. NEW & NOTEWORTHY Complement, a component of the innate immune system, is an important pathophysiological contributor to ethanol-induced liver injury. We have identified a novel role for factor D, a component of the alternative pathway, in protecting the liver from ethanol-induced inflammation, accumulation of apoptotic hepatocytes, and profibrotic responses. These data indicate a dual role of complement with regard to inflammatory and protective responses and suggest that accumulation of apoptotic cells impairs hepatic healing/recovery during alcoholic liver disease.

High Prevalence of Liver Fibrosis Among European Adults With Unknown Liver Disease: A Population-Based Study.

BACKGROUND & AIMS: Liver fibrosis is the main determinant of long-term outcome in chronic liver diseases. Little is known about the prevalence of liver fibrosis in the general population. The aim of the study was to investigate the prevalence of liver fibrosis in the general adult population with unknown liver disease. METHODS: This was a population-based, cross-sectional study performed in the Barcelona metropolitan area. Subjects aged 18 to 75 years old were identified randomly from citizens included in the primary health care registry. Of 4866 subjects invited, 3076 participated (63.2%). Liver fibrosis was estimated by measuring liver stiffness (LS) with transient elastography (TE). Liver histology was assessed in 92 subjects with increased LS. RESULTS: Prevalence estimates of increased LS (≥6.8, ≥8.0, and ≥9.0 kPa) were 9.0%, 5.8%, and 3.6%, respectively. The etiology of liver disease was mainly nonalcoholic fatty liver disease (NAFLD), followed by alcohol risk consumption (consumption of ≥21 standard drinking units/wk in men and ≥14 standard drinking units/wk in women). Factors independently associated with increased LS were male sex, abdominal obesity, type 2 diabetes, serum glucose, high-density lipoprotein, and triglyceride levels. Subjects without risk factors for NAFLD or without alcohol risk consumption had a very low prevalence of increased LS. The best cut-off value of LS for significant liver fibrosis (F2-F4) was 9.2 kPa, with high sensitivity and specificity. TE was more accurate than alanine aminotransferase, NAFLD fibrosis score, or Fibrosis 4. An algorithm for screening for liver fibrosis using TE in the community setting is proposed. CONCLUSIONS: These findings show a high prevalence of silent liver disease with advanced fibrosis mainly related to NAFLD in adult European subjects without known liver disease. An LS value less than 9.2 kPa predicts the absence of significant liver fibrosis with high accuracy and could be used for screening purposes.

Alcohol abstinence in patients surviving an episode of alcoholic hepatitis: Prediction and impact on long-term survival.

Alcoholic hepatitis (AH) is the most severe form of alcoholic liver disease. Most studies have focused on short-term prognosis, whereas factors associated with long-term survival are largely unknown. The aims of our study were to (1) determine the impact of complete abstinence from alcohol on long-term survival and (2) identify prognostic factors at admission capable of predicting abstinence during long-term follow-up in patients with AH. One hundred forty-two patients with biopsy-proven AH that survived the first episode were included. Demographic, psychiatric, and biochemical variables at admission and drinking status during follow-up were obtained. Cox regression, logistic regression, and classification and regression trees (CART) analyses were used for statistical analysis. Overall mortality was 38% with a median follow-up of 55 months. During follow-up, complete abstinence was reported in 39% and was associated with better long-term survival (hazard ratio, 0.53; P = 0.03). After adjustment for baseline prognostic scoring systems (Model for End-Stage Liver Disease and age, bilirubin, international normalized ratio, creatinine scores), complete abstinence was independently associated with survival (P < 0.05). Age and lack of past alcoholism treatments were independently associated with complete abstinence (P < 0.001 and P = 0.02, respectively) during follow-up. CART analysis generated a simple and practical algorithm based on the combination of past alcoholism treatments and age. Using CART analysis, we stratified 2 subgroups of patients with high (65%) and low (26%-29%) rates of complete abstinence after an episode of AH. CONCLUSION: Complete abstinence after an episode of AH positively impacts long-term survival. The combination of 2 variables easily obtained at admission might be useful to predict long-term abstinence after an episode of AH. Strategies aimed at promoting alcohol abstinence in these patients are necessary. (Hepatology 2017;66:1842-1853).

Deregulated neddylation in liver fibrosis.

Hepatic fibrosis is a global health problem currently without effective therapeutic approaches. Even though the ubiquitin-like posttranslational modification of neddylation, that conjugates Nedd8 (neural precursor cell expressed developmentally downregulated) to specific targets, is aberrant in many pathologies, its relevance in liver fibrosis (LF) remained unexplored. Our results show deregulated neddylation in clinical fibrosis and both in mouse bileductligation- and CCl4 -induced fibrosis. Importantly, neddylation inhibition, by using the pharmacological inhibitor, MLN4924, reduced liver injury, apoptosis, inflammation, and fibrosis by targeting different hepatic cell types. On one hand, increased neddylation was associated with augmented caspase 3 activity in bile-acid-induced apoptosis in mouse hepatocytes whereas neddylation inhibition ameliorated apoptosis through reduction of expression of the Cxcl1 and Ccl2 chemokines. On the other hand, chemokine receptors and cytokines, usually induced in activated macrophages, were reduced after neddylation inhibition in mouse Kupffer cells. Under these circumstances, decreased hepatocyte cell death and inflammation after neddylation inhibition could partly account for reduction of hepatic stellate cell (HSC) activation. We provide evidence that augmented neddylation characterizes activated HSCs, suggesting that neddylation inhibition could be important for resolving LF by directly targeting these fibrogenic cells. Indeed, neddylation inhibition in activated HSCs induces apoptosis in a process partly mediated by accumulation of c-Jun, whose cullin-mediated degradation is impaired under these circumstances. CONCLUSION: Neddylation inhibition reduces fibrosis, suggesting neddylation as a potential and attractive therapeutic target in liver fibrosis. (Hepatology 2017;65:694-709).

TLR7-let-7 Signaling Contributes to Ethanol-Induced Hepatic Inflammatory Response in Mice and in Alcoholic Hepatitis.

BACKGROUND: Toll-like receptor 7 (TLR7) is an endosomal TLR that is activated by single-stranded RNA, including endogenous microRNAs (e.g., let-7b). Increased hepatic expression of TLRs, microRNAs, and inflammatory mediators is linked to ethanol (EtOH) exposure and to alcoholic liver disease (ALD). ALD invovles chronic hepatic inflammation that can progress to alcoholic hepatitis (AH), a particularly severe form of ALD. This study aimed to investigate TLR7 expression in patients with different liver disease phenotypes and in mouse liver following alcohol exposure. METHODS: Hepatic mRNA expression was determined by RNA sequencing of liver tissue from patients with liver disease or normal liver tissue. Mice were exposed to subchronic EtOH followed by administration of the TLR7 agonist imiquimod. Primary human hepatocytes were exposed to EtOH or imiquimod in vitro. RESULTS: RNAseq analysis revealed that hepatic expression of TLR7 and let-7b microRNA, an endogenous TLR7 ligand, was significantly increased in AH patients. Hepatic expression of TLR7 and let-7b positively correlated with hepatic IL-8 mRNA expression. In mice, EtOH increased hepatic TLR7 mRNA expression and enhanced imiquimod-induced expression of the pro-inflammatory mediators TNFα, MCP-1, and iNOS. In vitro, EtOH significantly increased hepatocyte TLR7 mRNA and the TLR7 agonist, imiquimod, induced hepatocyte expression of TNFα and IL-8 mRNA. EtOH also increased the release of let-7b in microvesicles from hepatocytes, suggesting that EtOH can increase the expression of both the receptor and its endogenous ligand. CONCLUSIONS: These studies suggest that increased TLR7 signaling caused by increased expression of TLR7 and its endogenous ligand let-7b may contribute to the enhanced inflammatory response associated with AH.