Osteopontin characterizes bile duct-associated macrophages and correlates with liver fibrosis severity in primary sclerosing cholangitis

BACKGROUND AND AIMS

Primary sclerosing cholangitis (PSC) is an immune-mediated cholestatic liver disease for which pharmacological treatment options are currently unavailable. PSC is strongly associated with colitis and a disruption of the gut-liver axis, and macrophages are involved in the pathogenesis of PSC. However, how gut-liver interactions and specific macrophage populations contribute to PSC is incompletely understood.

APPROACH AND RESULTS

We investigated the impact of cholestasis and colitis on the hepatic and colonic microenvironment, and performed an in-depth characterization of hepatic macrophage dynamics and function in models of concomitant cholangitis and colitis. Cholestasis-induced fibrosis was characterized by depletion of resident KCs, and enrichment of monocytes and monocyte-derived macrophages (MoMFs) in the liver. These MoMFs highly express triggering-receptor-expressed-on-myeloid-cells-2 ( Trem2 ) and osteopontin ( Spp1 ), markers assigned to hepatic bile duct-associated macrophages, and were enriched around the portal triad, which was confirmed in human PSC. Colitis induced monocyte/macrophage infiltration in the gut and liver, and enhanced cholestasis-induced MoMF- Trem2 and Spp1 upregulation, yet did not exacerbate liver fibrosis. Bone marrow chimeras showed that knockout of Spp1 in infiltrated MoMFs exacerbates inflammation in vivo and in vitro , while monoclonal antibody-mediated neutralization of SPP1 conferred protection in experimental PSC. In human PSC patients, serum osteopontin levels are elevated compared to control, and significantly increased in advanced stage PSC and might serve as a prognostic biomarker for liver transplant-free survival.

CONCLUSIONS

Our data shed light on gut-liver axis perturbations and macrophage dynamics and function in PSC and highlight SPP1/OPN as a prognostic marker and future therapeutic target in PSC.

Systematic review: Glycomics as diagnostic markers for hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer with one of the highest cancer-related mortality rates worldwide. Early diagnosis is crucial for improving the therapeutic options and reducing the disease-related mortality.

AIM

To investigate serum N-glycomics as diagnostic markers for HCC.

METHODS

We performed a comprehensive search in PubMed, EMBASE, Web of Science and Scopus through August 17, 2023. Eligible studies assessed the potential use of serum N-glycomics as diagnostic biomarkers for HCC. Study selection, data extraction and quality assessment were performed by two independent reviewers.

RESULTS

Of the 48 articles included, 11 evaluated the utility of N-glycomics for the diagnosis of HCC in whole serum while the remaining articles focused on specific protein glycoforms or protein levels. Of these specific proteins, haptoglobin, alpha-fetoprotein (AFP), kininogen (Kin), α-1-antitrypsin and Golgi protein 73 (GP73) were the most frequently studied. Increased levels of fucosylation and branching presented as the most prevalent post-translational modifications of glycoproteins in patients with HCC compared to controls. Notably, glycomics-based biomarkers may provide a clinical benefit for the diagnosis of early HCC, as several algorithms achieved AUCs between 0.92-0.97. However, these were based on single studies with limited sample sizes and should therefore be validated.

CONCLUSIONS

Alterations in serum N-glycomics, characterised by increased levels of fucosylation and branching, have potential as diagnostic biomarkers for HCC. Optimisation of study design, patient selection and analysing techniques are needed before clinical implementation will be possible.

Patients hospitalized with alcohol-related liver disease and prior bariatric surgery are more prone to develop acute-on-chronic liver failure

BACKGROUND & AIMS

Patients with a history of bariatric surgery (BS) are susceptible to developing alcohol use disorder. We and others have previously shown that these patients can develop severe alcohol-related liver disease (ARLD). Our aim was to describe the demographics, co-morbidities and mortality of a hospitalized population diagnosed with alcohol-related liver disease, in relation to BS.

METHODS

We included 299 patients hospitalized with ARLD at the Ghent University Hospital between 1 January 2018 and 31 December 2022. Clinical, biochemical and outcome data were retrospectively retrieved from the most recent hospitalization. Statistical analysis was performed using the t test, Mann-Whitney U and χ2 tests.

RESULTS

Thirteen per cent (39/299) of patients admitted with ARLD had a history of bariatric surgery, of whom 25 (64.1%) had undergone Roux-en-Y gastric bypass. Patients with a history of BS were predominantly female (76.9%), in contrast to the non-BS population (29.2%) (p < .0001), and despite being significantly younger (p < .0001) and had a similar survival (61.5% vs. 58.1%). Bariatric surgery and older age at diagnosis were both significantly associated with poorer transplant-free survival. The cause of death was acute-on-chronic liver failure in 73.3% of BS patients, compared to only 19.2% of those without a history of BS (p < .0001). The weekly amount of alcohol consumed (p = .012) and duration of use (p < .0001) were significantly lower/shorter in the BS population.

CONCLUSIONS

BS patients hospitalized with ARLD are predominantly younger women with a lower cumulative alcohol consumption compared to those without prior BS. BS impacted transplant-free survival, with ACLF as the predominant cause of death in these patients.

FibroScan-aspartate aminotransferase (FAST) score for monitoring histological improvement in non-alcoholic steatohepatitis activity during semaglutide treatment: post-hoc analysis of a randomised, double-blind, placebo-controlled, phase 2b trial

Background

Currently, assessment of candidate pharmacotherapies in patients with non-alcoholic steatohepatitis (NASH) involves invasive liver biopsy. Non-invasive scores, such as the FibroScan-aspartate aminotransferase (FAST) score, are used to identify candidates for therapy, but their ability to assess disease progression or treatment effect is unknown. We aimed to assess the association between FAST score and histological endpoints.

Methods

We conducted a post-hoc analysis using data from a prior randomised, double-blind, placebo-controlled, phase 2b trial at 143 sites across 16 countries. Patients (aged 18-75 years) with biopsy-confirmed NASH, fibrosis stage 1-3, and a Non-alcoholic fatty liver disease Activity Score (NAS) ≥4 were enrolled between January 2017 and September 2018, and randomly assigned to receive once-daily subcutaneous semaglutide 0.1, 0.2, or 0.4 mg or placebo for 72 weeks. A subgroup analysis of patients with FAST score and histological data in the pooled semaglutide treatment and placebo arms at baseline and week 72 was performed. The original trial is registered at ClinicalTrials.gov, NCT02970942.

Findings

A total of 122 patients were included in this post-hoc analysis (93 received semaglutide and 29 received placebo). FAST score reduction was associated with achieving the primary endpoint of NASH resolution without worsening of fibrosis in the pooled semaglutide group (area under the receiver operating curve 0.69; 95% confidence interval [CI] 0.58, 0.81). Mean FAST score reduction from baseline to week 72 was greatest in patients who met the primary endpoint vs those who did not in both the semaglutide (-0.40 [95% CI -0.84, 0.04] vs -0.22 [95% CI -0.74, 0.30] points; p = 0.002) and placebo groups (-0.25 [95% CI -0.72, 0.23] vs 0.00 [95% CI -0.50, 0.50] points; p = 0.047). Similarly, mean reductions in FAST score at week 72 were greater in those with NAS improvement vs those without in the semaglutide and placebo groups (≥1 point, -0.36 [95% CI -0.82, 0.11] vs -0.08 [95% CI -0.53, 0.38] points [p < 0.001] and -0.25 [95% CI -0.64, 0.14] vs -0.06 [95% CI -0.40, 0.53] points [p = 0.001]; ≥2 points, -0.40 [95% CI -0.86, 0.06] vs -0.14 [95% CI -0.56, 0.28] points [p < 0.001] and -0.29 [95% CI -0.67, 0.09] vs -0.05 [95% CI -0.40, 0.50] points; [p < 0.001]). A FAST score reduction of more than 0.22 points after semaglutide treatment was associated with meeting the primary endpoint (sensitivity 78%; specificity 60%; positive likelihood ratio 1.26; negative likelihood ratio 0.25; odds ratio 4.93).

Interpretation

The potential of the FAST score as a non-invasive monitoring tool to identify histological changes following treatment requires further evaluation and validation.

Funding

Novo Nordisk A/S.

Limitations of PLX3397 as a microglial investigational tool: peripheral and off-target effects dictate the response to inflammation

Microglia, the resident macrophages of the central nervous system (CNS), play a critical role in CNS homeostasis and neuroinflammation. Pexidartinib (PLX3397), a colony-stimulating factor 1 (CSF1) receptor inhibitor, is widely used to deplete microglia, offering flexible options for both long-term depletion and highly versatile depletion-repopulation cycles. However, the potential impact of PLX3397 on peripheral (immune) cells remains controversial. Until now, the microglia-specificity of this type of compounds has not been thoroughly evaluated, particularly in the context of peripherally derived neuroinflammation. Our study addresses this gap by examining the effects of PLX3397 on immune cells in the brain, liver, circulation and bone marrow, both in homeostasis and systemic inflammation models. Intriguingly, we demonstrate that PLX3397 treatment not only influences the levels of tissue-resident macrophages, but also affects circulating and bone marrow immune cells beyond the mononuclear phagocyte system (MPS). These alterations in peripheral immune cells disrupt the response to systemic inflammation, consequently impacting the phenotype irrespective of microglial depletion. Furthermore, we observed that a lower dose of PLX3397, which does not deplete microglia, demonstrates similar (non-)MPS effects, both in the periphery and the brain, but fails to fully replicate the peripheral alterations seen in the higher doses, questioning lower doses as a 'peripheral control' strategy. Overall, our data highlight the need for caution when interpreting studies employing this compound, as it may not be suitable for specific investigation of microglial function in the presence of systemic inflammation.

Letter: Detecting unreported alcohol consumption in patients with NAFLD - Standardisation is urgent. Authors' reply

This article is linked to Magherman et al papers. To view these articles, visit https://doi.org/10.1111/apt.17388 and https://doi.org/10.1111/apt.17723

Hepatic safety and efficacy of immunomodulatory drugs used in patients with autoimmune hepatitis

BACKGROUND AND AIMS

There is little data on the hepatic efficacy and safety of immunomodulatory drugs used in patients with autoimmune hepatitis (AIH), despite their established use in dermatology, rheumatology and inflammatory bowel diseases (IBD). Our aim was to collect real-life data on the experience of expert centres in treating AIH patients with these drugs, considered unconventional for AIH management.

METHODS

Online survey among hepatology centres being part of the European Reference Network on Hepatological Diseases (ERN RARE-LIVER).

RESULTS

25 AIH patients have been reported. Ten were female, median age at diagnosis was 28 years; median follow-up was 17 months. All had initially received AIH-standard treatment. AIH-unconventional treatment was initiated for concomitant autoimmune diseases in 15 cases: nine for IBD (five vedolizumab and four ustekinumab), and one each for following diseases: autoinflammatory syndrome (tocilizumab), chronic urticaria (omalizumab), rheumatoid arthritis (abatacept), psoriasis (guselkumab), psoriatric arthritis (secukinumab, followed by ustekinumab) and alopecia (ruxolitinib). Three patients were treated with immunomodulatory drugs for side effects of previous treatments, including two patients with IBD treated with vedolizumab and ustekinumab, respectively, and one treated with belimumab. At the end of follow-up, 13 patients were in complete biochemical response, the patient on omalizumab had a relapse, and four patients with concomitant IBD had insufficient response. Seven patients were treated for lack of biochemical remission, of whom six with belimumab, all initially reaching complete biochemical response, but five relapsing during follow-up; and one with secukinumab, having concomitant rheumatoid arthritis and ankylosing spondylitis, reaching complete biochemical response. Only the patient on abatacept received unconventional treatment as monotherapy. Side effects were reported in two patients on belimumab: one recurrent soft tissue infections, one fatigue and arthralgia.

CONCLUSION

Among 25 AIH patients who were treated with immunomodulatory drugs for different reasons, the majority had a fovorable course, relapse was frequent in difficult-to-treat patients who received belimumab, and four with concomitant IBD had insufficient response.

A remarkable presentation of a massive Budd-Chiari syndrome

A 59-year-old female presented to the emergency department with malaise, significant weight loss, abdominal discomfort, dyspnoea and severely swollen peripheral extremities. She had a past medical history of sickle cell anaemia, a latent tuberculosis infection and a chronic hepatitis B that was treated with PEG-interferon alpha-2 in 2008. Since 2018, she was lost to follow-up. The patient was critically ill, sarcopenic and lethargic. Clinical examination revealed icteric sclerae and a markedly distended and diffusely tender abdomen and peripheral oedemas. Her vital signs included a blood pressure of 105/64 mmHg, tachycardia of 130 bpm, hypothermia of 35.6°C and a SpO2 of 100% in ambient air. Laboratory workup demonstrated a total bilirubin of 12.9 mg/dL, AST 500 U/L, ALT 218 U/L, ALP 178 U/L and GGT 126 U/L, a thrombocytopenia of 34 x10E3/ μL, 16,01 x10E3/μL leukocytes, a CRP of 94.8 mg/L and a lactate of 10,12 mmol/L. The serum creatinine was 1.04 mg/dL, eGFR 54.1 ml/min. The INR was 2.77 and there was a severe hypoalbuminemia (22 g/L). D-dimers were >20 000 ng/ml. The patient presented also with spontaneous hypoglycaemia. A multiphasic contrast-enhanced thoracic and abdominal computed tomography (CT) was performed (figure 1). Given the results of the CT, a 2D echocardiogram was urgently requested (figure 2).

Etiology and Outcome of Adult and Pediatric Acute Liver Failure in Europe

Acute liver failure (ALF) is rare but life-threatening. Common causes include intoxications, infections, and metabolic disorders. Indeterminate etiology is still frequent. No systematic data on incidence, causes, and outcome of ALF across Europe are available. Via an online survey we reached out to European Reference Network Centers on rare liver diseases. Numbers and etiology of ALF cases during 2020 were retrieved and diagnostic and treatment availabilities assessed. In total, 455 cases (306 adult, 149 pediatric) were reported from 36 centers from 20 countries. Intoxication was the most common cause in adult and pediatric care. The number of cases with indeterminate etiology is low. Diagnostic tools and specific treatment options are broadly available within this network. This is the first approach to report on etiology and outcome of ALF in the pediatric and adult population in Europe. High diagnostic yield and standard of care reflects the expert status of involved centers.

An unusual cause of portal hypertension

A 66-year-old male with a medical history of coronary artery disease presented with nonspecific symptoms of anorexia, lethargy and an increase in abdominal girth. He was diagnosed 3 months ago with chronic liver disease of undetermined aetiology. He did not smoke and was a social drinker till 4 months ago. He was taking tests showed progressive cholestatic liver enzymes (total bilirubin 1,09 mg/dL, AST 130 U/L, ALT 129 U/L, GGT 517 U/L and ALP 641 U/L) and a severe hypoalbuminemia. Laboratory workup made a metabolic, autoimmune, and viral aetiology of the suspected cirrhosis less probable. Urinalysis showed a rapidly progressive proteinuria in the nephrotic range accompanied by the presence of serum spike of monoclonal lambda light Furosemide, Aldactone, Pantoprazole, Acetylcysteine and Atorvastatin. He had no personal or familial history of liver diseases. Physical examination revealed a tender but distended abdomen and large ascites was present. The laboratory chain protein on electrophoresis with immunofixation. Doppler echocardiography revealed a hypertrophic cardiomyopathy based on diffuse left and right ventricular hypertrophy with relative apical sparing. A diagnostic paracentesis was undertaken and the results were consistent with portal hypertension (SAAG 1,6 g/ dL). Considering the concomitant presence of hypertrophic cardiomyopathy, nephrotic syndrome and a presentation of portal hypertension of undetermined aetiology in presence of a monoclonal IgG lambda light chain spike, a transjugular liver biopsy (figure 1 and 2) was performed with HVPG measurement consistent with significant portal hypertension (15 mmHg).

Transient Kupffer cell depletion and subsequent replacement by infiltrating monocyte-derived cells does not alter the induction or progression of hepatocellular carcinoma

Due to a combination of rapid disease progression and the lack of curative treatment options, hepatocellular carcinoma (HCC) is one of the deadliest cancers worldwide. Infiltrated, monocyte-derived, tumor-associated macrophages are known to play a role in HCC pathogenesis, but the involvement of Kupffer cells (KCs) remains elusive. Here, we used the Clec4F-diphteria toxin receptor transgenic mouse model to specifically investigate the effect of KC depletion on HCC initiation, progression and neoplastic growth following liver resection. For this purpose, several HCC mouse models with varying underlying etiologies were used and partial hepatectomy was performed. Our results show that in HCC, developed on a fibrotic or non-alcoholic steatohepatitis background, depletion of embryonic KCs at the onset of HCC induction and the subsequent replacement by monocyte-derived KCs does not affect the tumor burden, tumor microenvironment or the phenotype of isolated KCs at end-stage disease. In non-chronic liver disease-associated diethylnitrosamine-induced HCC, ablation of Clec4F+ KCs did not alter tumor progression or neoplastic growth following liver resection. Our results show that temporal ablation of resident KCs does not impact HCC pathogenesis, neither in the induction phase nor in advanced disease, and indicate that bone marrow-derived KCs are able to swiftly repopulate the available KC niche and adopt their phenotype.

Experimental hepatic encephalopathy causes early but sustained glial transcriptional changes

Hepatic encephalopathy (HE) is a common complication of liver cirrhosis, associated with high morbidity and mortality, for which no brain-targeted therapies exist at present. The interplay between hyperammonemia and inflammation is thought to drive HE development. As such, astrocytes, the most important ammonia-metabolizing cells in the brain, and microglia, the main immunomodulatory cells in the brain, have been heavily implicated in HE development. As insight into cellular perturbations driving brain pathology remains largely elusive, we aimed to investigate cell-type specific transcriptomic changes in the HE brain. In the recently established mouse bile duct ligation (BDL) model of HE, we performed RNA-Seq of sorted astrocytes and microglia at 14 and 28 days after induction. This revealed a marked transcriptional response in both cell types which was most pronounced in microglia. In both cell types, pathways related to inflammation and hypoxia, mechanisms commonly implicated in HE, were enriched. Additionally, astrocytes exhibited increased corticoid receptor and oxidative stress signaling, whereas microglial transcriptome changes were linked to immune cell attraction. Accordingly, both monocytes and neutrophils accumulated in the BDL mouse brain. Time-dependent changes were limited in both cell types, suggesting early establishment of a pathological phenotype. While HE is often considered a unique form of encephalopathy, astrocytic and microglial transcriptomes showed significant overlap with previously established gene expression signatures in other neuroinflammatory diseases like septic encephalopathy and stroke, suggesting common pathophysiological mechanisms. Our dataset identifies key molecular mechanisms involved in preclinical HE and provides a valuable resource for development of novel glial-directed therapeutic strategies.

Meta-analysis: The impact of light-to-moderate alcohol consumption on progressive non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) is defined as fatty liver disease in the absence of heavy alcohol consumption. However, the impact of light-to-moderate alcohol consumption on progressive NAFLD and on mortality is presently unclear.

METHODS

Medline, Embase, OATD and OpenGrey were systematically searched up to November 2022 for relevant cross-sectional, case-control and cohort studies. The study outcomes were progressive NAFLD-steatohepatitis (NASH), fibrosis, cirrhosis, hepatocellular carcinoma (HCC) and mortality. The entire review process was performed by two independent reviewers. A narrative synthesis was performed for all outcomes, while meta-analyses, subgroup analyses and publication bias assessment were performed depending on the number of articles.

RESULTS

After study selection, 32 articles were included. Cohort studies reported that moderate alcohol intake increased the risk for advanced fibrosis (pooled OR 1.56; 95% CI 1.08-2.26 and HR 1.39; 95% CI 1.22-1.57), which was not observed in cross-sectional studies. Alcohol use also increased the risk of developing liver cirrhosis and HCC, but seemed to lower the risk of steatohepatitis. Light alcohol consumption protected against all-cause mortality, an effect not observed in NAFLD patients with moderate intake.

CONCLUSIONS

There is wide heterogeneity in studies on the impact of alcohol on progressive NAFLD. Nevertheless, cohort studies reported a significant harmful effect of moderate alcohol consumption on the occurrence of advanced fibrosis. Further research is needed to make valid recommendations with regard to alcohol consumption in patients with NAFLD.

Liver health and the interplay between obesity, alcohol and bariatric surgery

The prevalence of obesity and metabolic consequences, including non-alcoholic fatty liver disease (NAFLD) has become a global health problem. Obesity has an important impact on chronic liver disease even beyond NAFLD, as it accelerates the progression of alcohol liver disease. Conversely, even moderate alcohol use can affect NAFLD disease severity. Weight loss is the gold standard treatment but adherence to lifestyle changes is very low in the clinical setting. Bariatric surgery can improve metabolic components and cause long-term weight loss. Therefore, bariatric surgery could serve as an attractive treatment option for NAFLD patients. A pitfall is the use of alcohol after bariatric surgery. This short review integrates data about the influence of obesity and alcohol on liver function and the role of bariatric surgery.

Glycomics-based serum markers as reliable tool for assessment of viral response after treatment with direct-acting antiviral drugs in hepatitis C virus infection

OBJECTIVES

Patients with chronic hepatitis C virus (HCV) infection have a genuine risk of developing liver fibrosis and cirrhosis, potentially resulting in hepatocellular carcinoma (HCC), a risk that remains even after sustained viral response (SVR). Glycomics-based biomarkers are an attractive tool to closely monitor these patients during and after antiviral treatment, as alterations in the abundance of N-glycans reflect an altered state of the liver. This study assessed serum glycomics for the evaluation of inflammation-related fibrosis regression during and after treatment of HCV with DAAs.

METHODS

The GlycoFibroTest and GlycoCirrhoTest were analyzed in the sera 36 HCV-infected patients with advanced fibrosis (F3) or established cirrhosis (F4), before (week 0), during (week 12) and after (week 24) a twelve-week oral administration of DAAs therapy - using an optimized glycomic technology on a DNA sequencer.

RESULTS

All patients achieved SVR after treatment and two of them developed HCC in the subsequent five years. A significant decrease of the GlycoFibroTest (p < 0.0001) was seen after 12 weeks, consistent with other measured biomarkers (APRI, FIB-4, FibroTest). Statistical analysis was performed in IBM SPSS Statistics version 28.0, using the non-parametric Friedman's test with a statistical significance α level of 0.05.

CONCLUSION

This study suggests that the GlycoFibroTest is a serum biomarker for viral response in HCV patients. The rapid decrease of the glycomics-based biomarker probably reflects the amelioration of liver inflammation as underlying process, rather than the improvement of liver fibrosis itself.

Improving quality of life in patients with rare autoimmune liver diseases by structured peer-delivered support (Q.RARE.LI): study protocol for a transnational effectiveness-implementation hybrid trial

BACKGROUND

Psychosocial support is a crucial component of adequate rare disease care, but to date psychosocial support needs of this patient population are insufficiently met. Within Q.RARE.LI, we strive to evaluate the effectiveness of a structured, transdiagnostic, and location-independent psychosocial support intervention in routine care of patients with rare autoimmune liver diseases in five countries and prepare its implementation.

METHODS

Within an effectiveness-implementation hybrid trial, we aim to a) investigate the effectiveness of the intervention in routine care in five diverse healthcare systems and b) assess implementation outcomes, examine and prepare the implementation context, and develop country-specific implementation strategies. To assess effectiveness, we will include N = 240 patients with rare autoimmune liver diseases. Within a two-armed randomized controlled trial (allocation ratio 1:1), we will compare structured and peer-delivered psychosocial support in addition to care-as-usual (CAU) with CAU alone. Outcomes will be assessed via electronic database entry prior to intervention, directly after, and at a three-month follow-up. Our primary effectiveness outcome will be mental health-related quality of life at post-assessment. Secondary outcomes include depression and anxiety severity, perceived social support, helplessness, and disease acceptance. Implementation outcomes will be assessed within a mixed-methods process evaluation. In a quantitative cross-sectional survey, we will examine perceived acceptability and feasibility in patients, peer-counselors, and healthcare providers involved in delivery of the intervention. In qualitative focus groups, we will analyze the implementation context and determine barriers and facilitators for implementation with different stakeholders (patients and/or representatives, peer-counselors, healthcare providers, health insurers). Based on these results, we will derive country-specific implementation strategies and develop a concrete implementation plan for each country.

DISCUSSION

The intervention is expected to help patients adjust to their disease and improve their mental quality of life. The transdiagnostic and location-independent program has the potential to reach patients for psychosocial support who are usually hard to reach. By preparing the implementation in five countries, the project can help to make low-threshold psychosocial support available to many patients with rare diseases and improve comprehensive healthcare for an often neglected group.

TRIAL REGISTRATION

ISRCTN15030282.

Bariatric surgery for non-alcoholic fatty liver disease: Indications and post-operative management

The prevalence of obesity and metabolic consequences such as nonalcoholic fatty liver diseases (NAFLD) has become a crucial health problem. Lifestyle modifications, especially weight loss, effectively reduces liver injury in NAFLD patients. However, adherence to lifestyle changes is very low in the clinical setting. Bariatric surgery can improve metabolic components and cause long-term weight loss. Therefore, bariatric surgery could serve as an attractive treatment option for NAFLD patients. This review integrates data about the benefits of bariatric surgery on NAFLD but also describes the potential pitfalls.

Kupffer Cells Contested as Early Drivers in the Pathogenesis of Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is an idiopathic chronic immune-mediated cholestatic liver disease characterized by fibro-inflammatory bile duct strictures, progressive hepatobiliary fibrosis, and gut-liver axis disruption. The pathophysiology of PSC remains insufficiently characterized, which hampers the development of effective therapies. Hepatic macrophages (MFs) are implicated in PSC pathogenesis, but the exact role of Kupffer cells (KCs) is unclear. Using the latest markers to discriminate resident KCs (ResKCs) from their monocyte-derived counterparts (MoKCs), and two models for intrahepatic and extrahepatic cholestasis, respectively, this study shows that CLEC4F⁺TIM4⁺ ResKCs are depleted after chronic cholestatic liver injury, whereas infiltrating CLEC4F⁺TIM4^- MoKCs are already enriched during the acute phase. Transcriptional profiling of hepatic MF subsets during early cholestatic injury indicates that ResKCs are indeed activated and that MoKCs express even higher levels of pro-inflammatory and proliferative markers compared with ResKCs. Conditional depletion of KCs, by using Clec4f^DTR transgenic mice, before and during early cholestasis induction had no effect, however, on the composition of the hepatic myeloid cell pool following injury progression and did not affect disease outcomes. Taken together, these results provide new insights on the heterogeneity of the MF pool during experimental PSC and evidence that depletion of resident and activated KCs during sclerosing cholangitis does not affect disease outcome in mice.

Viral clade is associated with severity of symptomatic genotype 3 hepatitis E virus infections in Belgium, 2010-2018

BACKGROUND & AIMS

HEV genotype (gt) 3 infections are prevalent in high-income countries and display a wide spectrum of clinical presentations. Host - but not viral - factors are reported to be associated with worse clinical outcomes.

METHODS

Demographic, clinical, and biochemical data laboratory-confirmed HEV infections (by PCR and/or a combination of IgM and IgG serology) at the Belgian National Reference Centre between January 2010 and June 2018 were collected using standardised case report forms. Genotyping was based on HEV open reading frame 2 sequences. Serum CXCL10 levels were measured by a magnetic bead-based assay. H&E staining was performed on liver biopsies.

RESULTS

A total of 274 HEV-infected individuals were included. Subtype assignment was possible for 179/218 viraemic cases, confirming gt3 as dominant with an almost equal representation of clades abchijklm and efg. An increased hospitalisation rate and higher peak serum levels of alanine aminotransferase, bilirubin, and alkaline phosphatase were found in clade efg-infected individuals in univariate analyses. In multivariable analyses, clade efg infections remained more strongly associated with severe disease presentation than any of the previously identified host risk factors, being associated with a 2.1-fold higher risk of hospitalisation (95% CI 1.1-4.4, p = 0.034) and a 68.2% higher peak of bilirubin levels (95% CI 13.3-149.9, p = 0.010), independently of other factors included in the model. In addition, acute clade efg infections were characterised by higher serum CXCL10 levels (p = 0.0005) and a more pronounced liver necro-inflammatory activity (p = 0.022).

CONCLUSIONS

In symptomatic HEV gt3 infections, clade efg is associated with a more severe disease presentation, higher serum CXCL10 levels, and liver necro-inflammatory activity, irrespective of known host risk factors.

CLINICAL TRIAL REGISTRATION

The protocol was submitted to clinicaltrials.gov (NCT04670419).

IMPACT AND IMPLICATIONS

HEV genotype (gt) 3 infections display a wide spectrum of clinical presentations currently ascribed to host factors. Here we examined the role of viral factors on liver disease outcomes by combining viral phylogeny with clinical, biochemical, cytokine, and histological data from 274 Belgian adults infected with HEV presenting between 2010 and 2018. HEV gt 3 clade efg infections were associated with a more severe disease presentation, higher serum CXCL10 levels and liver necro-inflammatory activity, irrespective of known host risk factors. HEV gt3 clade-dependent clinical outcomes call for broad HEV gt3 subtyping in clinical practice and research to help identify those at higher risk for worse outcomes and to further unravel underlying virus-host interactions.

Intensive Lifestyle Management Improves Steatosis and Fibrosis in Pediatric Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Childhood obesity, with associated comorbidities such as nonalcoholic fatty liver disease (NAFLD), is an increasing global health problem. Although lifestyle management is the mainstay of treatment, its efficacy on liver fibrosis has not yet been established.

METHODS

Children and adolescents admitted for severe obesity at a tertiary center (Zeepreventorium, De Haan, Belgium) were enrolled in this prospective study. Intensive lifestyle therapy encompassed caloric restriction, physical activity, education on a healthy lifestyle, and psychosocial support. At baseline, 6 months, and 12 months, liver ultrasound and transient elastography with controlled attenuation parameter were performed to assess liver steatosis and fibrosis.

RESULTS

A total of 204 patients (median age, 14.0 y; body mass index Z-score, +2.8) were evaluated at admission. NAFLD on ultrasound was present in 71.1%, whereas 68.6% had controlled attenuation parameter values of 248 dB/m or greater. A total of 32.8% of patients had at least F2 fibrosis, including 10.3% with transient elastography of 9 kPa or greater. After 6 months, the median body weight loss was 16.0% in the 167 patients evaluated. Fibrosis improved in 75.0% (P < .001). Baseline severity of liver fibrosis and steatosis were predictors of fibrosis resolution. Seventy-nine patients had reached the 1-year time point. The improvements were sustained because fibrosis regressed at least 1 stage in all patients with baseline fibrosis. Fasting serum alanine aminotransferase and homeostasis model assessment of insulin resistance decreased significantly over the 1-year period (P < .001).

CONCLUSIONS

NAFLD and associated fibrosis are highly prevalent in children and adolescents with severe obesity. An intensive multidisciplinary lifestyle management program that causes significant weight loss not only improves liver steatosis, but also fibrosis.

Different Models to Predict the Risk of Recurrent Hepatocellular Carcinoma in the Setting of Liver Transplantation

Simple Summary

Liver transplantation is considered the first-choice curative therapy for hepatocellular carcinoma in the early phase of the disease, when surgical resection is not possible. Even when implementing restrictive criteria to select patients for liver transplantation, there is a risk of recurrence in the transplanted liver, influencing the long-term outcome and prognosis. As it is challenging to predict the individual risk of recurrence, there is a need for validated and predictive scoring systems to use to stratify patients before and/or after liver transplantation. Most of the proposed scorings include biological markers for tumour behavior, in addition to the number and size of tumoral nodules. In this review, we discuss different published models to assess the risk of recurrent hepatocellular carcinoma after transplantation. Our aim is to refine clinical decisions about prioritization and listing for liver transplantation, to better inform patients and provide an appropriate surveillance strategy to influence their prognosis.

Abstract

Liver transplantation is the preferred therapeutic option for non-resectable hepatocellular carcinoma in early-stage disease. Taking into account the limited number of donor organs, liver transplantation is restricted to candidates with long-term outcomes comparable to benign indications on the waiting list. Introducing the morphometric Milan criteria as the gold standard for transplant eligibility reduced the recurrence rate. Even with strict patient selection, there is a risk of recurrence of between 8 and 20% in the transplanted liver, and this is of even greater importance when using more expanded criteria and downstaging protocols. Currently, it remains challenging to predict the risk of recurrence and the related prognosis for individual patients. In this review, the recurrence-risk-assessment scores proposed in the literature are discussed. Currently there is no consensus on the optimal model or the implications of risk stratification in clinical practice. The most recent scorings include additional biological markers for tumour behavior, such as alfa-foetoprotein, and the response to locoregional therapies, in addition to the number and diameter of tumoral nodules. The refinement of the prediction of recurrence is important to better inform patients, guide decisions about prioritization and listing and implement individualized surveillance strategies. In the future, this might also provide indications for tailored immunosuppressive therapy or inclusion in trials for adjuvant treatment.

Combined Therapy with a CCR2/CCR5 Antagonist and FGF21 Analogue Synergizes in Ameliorating Steatohepatitis and Fibrosis

(1) Background: With new potential drug targets emerging, combination therapies appear attractive to treat non-alcoholic steatohepatitis (NASH) and fibrosis. Chemokine receptor CCR2/5 antagonists can improve fibrosis by reducing monocyte infiltration and altering hepatic macrophage subsets. Fibroblast growth factor 21 (FGF21) may improve NASH by modulating lipid and glucose metabolism. We compared effects of single drug to combination treatment as therapeutic strategies against NASH. (2) Methods: We analyzed serum samples and liver biopsies from 85 nonalcoholic fatty liver disease (NAFLD) patients. A CCR2/5 inhibitor (BMS-687681-02-020) and a pegylated FGF21 agonist (BMS-986171) were tested in male C57BL/6J mice subjected to dietary models of NASH and fibrosis (choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) up to 12 weeks; short- (2w) or long-term (6w) treatment). (3) Results: In NAFLD patients, chemokine CCL2 and FGF21 serum levels correlated with inflammatory serum markers, only CCL2 was significantly associated with advanced liver fibrosis. In rodent NASH, CCR2/5 inhibition significantly reduced circulating Ly6C+ monocytes and hepatic monocyte-derived macrophages, alongside reduced hepatic inflammation and fibrosis. FGF21 agonism decreased body weight, liver triglycerides and histological NASH activity. Combination treatment reflected aspects of both compounds upon short- and long-term application, thereby amplifying beneficial effects on all aspects of steatohepatitis and fibrosis. (4) Conclusions: CCR2/5 inhibition blocks hepatic infiltration of inflammatory monocytes, FGF21 agonism improves obesity-related metabolic disorders. Combined therapy ameliorates steatohepatitis and fibrosis more potently than single drug treatment in rodent NASH, corroborating the therapeutic potential of combining these two approaches in NASH patients.

Maternal and Perinatal Risk Factors for Pediatric Nonalcoholic Fatty Liver Disease: A Systematic Review

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) has become the most common pediatric liver disease. The intrauterine and early life environment can have an important impact on long-term metabolic health. We investigated the impact of maternal prepregnancy obesity, (pre)gestational diabetes, breastfeeding, and birth anthropometrics/preterm birth on the development of NAFLD in children and adolescents.

METHODS

A comprehensive search was performed in MEDLINE, PubMed Central, EMBASE, and grey literature databases through August 2020. The primary outcome was the prevalence of pediatric NAFLD, whereas the histologic severity of steatohepatitis and/or fibrosis were secondary outcomes. Study selection, data extraction, and quality assessment were performed by 2 independent reviewers.

RESULTS

Our systematic review included 33 articles. Study heterogeneity regarding patient populations, diagnostic tools, and overall quality was considerable. Eight studies determined the impact of maternal prepregnancy overweight/obesity and identified this as a possible modifiable risk factor for pediatric NAFLD. Conversely, 8 studies investigated (pre)gestational diabetes, yet the evidence on its impact is conflicting. Breastfeeding was associated with a reduced risk for NAFLD, steatohepatitis, and fibrosis, especially in studies that evaluated longer periods of breastfeeding. Being born preterm or small for gestational age has an unclear impact on the development of NAFLD, although an early catch-up growth might drive NAFLD.

CONCLUSIONS

In a systematic review, we found that maternal prepregnancy overweight and obesity were associated with an increased risk of pediatric NAFLD. Breastfeeding might be protective against the development of NAFLD when the duration of breastfeeding is sufficiently long (≥6 months).

90Y Radioembolization versus Drug-eluting Bead Chemoembolization for Unresectable Hepatocellular Carcinoma: Results from the TRACE Phase II Randomized Controlled Trial

Background Transarterial chemoembolization (TACE) is the recommended treatment for intermediate hepatocellular carcinoma (HCC) according to the Barcelona Clinic Liver Cancer guidelines. Prospective uncontrolled studies suggest that yttrium 90 (⁹⁰Y) transarterial radioembolization (TARE) is a safe and effective alternative. Purpose To compare the efficacy and safety of TARE with TACE for unresectable HCC. Materials and Methods In this single-center prospective randomized controlled trial (TRACE), ⁹⁰Y glass TARE was compared with doxorubicin drug-eluting bead (DEB) TACE in participants with intermediate-stage HCC, extended to Eastern Cooperative Oncology Group performance status 1 and those with early-stage HCC not eligible for surgery or thermoablation. Participants were recruited between September 2011 and March 2018. The primary end point was time to overall tumor progression (TTP) (Kaplan-Meier analysis) in the intention-to-treat (ITT) and per-protocol (PP) groups. Results At interim analysis, 38 participants (median age, 67 years; IQR, 63-72 years; 33 men) were randomized to the TARE arm and 34 (median age, 68 years; IQR, 61-71 years; 30 men) to the DEB-TACE arm (ITT group). Median TTP was 17.1 months in the TARE arm versus 9.5 months in the DEB-TACE arm (ITT group hazard ratio [HR], 0.36; 95% CI: 0.18, 0.70; P = .002) (PP group, 32 and 34 participants, respectively, in each arm; HR, 0.29; 95% CI: 0.14, 0.60; P < .001). Median overall survival was 30.2 months after TARE and 15.6 months after DEB-TACE (ITT group HR, 0.48; 95% CI: 0.28, 0.82; P = .006). Serious adverse events grade 3 or higher (13 of 33 participants [39%] vs 19 of 36 [53%] after TARE and DEB-TACE, respectively; P = .47) and 30-day mortality (0 of 33 participants [0%] vs three of 36 [8.3%]; P = .24) were similar in the safety groups. At the interim, the HR for the primary end point, TTP, was less than 0.39, meeting the criteria to halt the study. Conclusion With similar safety profile, yttrium 90 radioembolization conferred superior tumor control and survival compared with chemoembolization using drug-eluting beads in selected participants with early or intermediate hepatocellular carcinoma. Clinical trial registration no. NCT01381211 © RSNA, 2022 Online supplemental material is available for this article.

Serum Glycomics on Postoperative Day 7 Are Associated With Graft Loss Within 3 Months After Liver Transplantation Regardless of Early Allograft Dysfunction

BACKGROUND

Prediction of outcome after liver transplantation (LT) is limited by the lack of robust predictors of graft failure. In this prospective study, we aimed to define a serum glycomic signature in the first week after LT that is associated with graft loss at 3 mo after LT.

METHODS

Patients were included between January 1, 2011, and February 28, 2017. Glycomic analysis was performed using DNA sequencer-associated fluorophore-associated capillary electrophoresis on a serum sample 1 wk after LT. Making use of Lasso regression, an optimal glycomic signature was identified associated with 3-mo graft survival.

RESULTS

In this cohort of 131 patients, graft loss at 3 mo occurred in 14 patients (11.9%). The optimal mode, called the GlycoTransplantTest, yielded an area under the curve of 0.95 for association with graft loss at 3 mo. Using an optimized cutoff for this biomarker, sensitivity was 86% and specificity 89%. Negative predictive value was 98%. Odds ratio for graft loss at 3 mo was 70.211 (P < 0.001; 95% confidence interval, 10.876-453.231).

CONCLUSIONS

A serum glycomic signature is highly associated with graft loss at 3 mo. It could support decision making in early retransplantation.

The neurogliovascular unit in hepatic encephalopathy

Hepatic encephalopathy (HE) is a neurological complication of hepatic dysfunction and portosystemic shunting. It is highly prevalent in patients with cirrhosis and is associated with poor outcomes. New insights into the role of peripheral origins in HE have led to the development of innovative treatment strategies like faecal microbiota transplantation. However, this broadening of view has not been applied fully to perturbations in the central nervous system. The old paradigm that HE is the clinical manifestation of ammonia-induced astrocyte dysfunction and its secondary neuronal consequences requires updating. In this review, we will use the holistic concept of the neurogliovascular unit to describe central nervous system disturbances in HE, an approach that has proven instrumental in other neurological disorders. We will describe HE as a global dysfunction of the neurogliovascular unit, where blood flow and nutrient supply to the brain, as well as the function of the blood-brain barrier, are impaired. This leads to an accumulation of neurotoxic substances, chief among them ammonia and inflammatory mediators, causing dysfunction of astrocytes and microglia. Finally, glymphatic dysfunction impairs the clearance of these neurotoxins, further aggravating their effect on the brain. Taking a broader view of central nervous system alterations in liver disease could serve as the basis for further research into the specific brain pathophysiology of HE, as well as the development of therapeutic strategies specifically aimed at counteracting the often irreversible central nervous system damage seen in these patients.

Bariatric surgery and the liver-Mechanisms, benefits, and risks

The prevalence of obesity and metabolic diseases such as type 2 diabetes and nonalcoholic fatty liver disease (NAFLD) has risen dramatically over the past decades. At present, bariatric surgery is the most effective treatment for this global health problem, through effects on food intake, gut hormone secretion, metabolic signaling pathways, and adipose tissue dysfunction. The liver occupies a central role in carbohydrate, protein, and lipid metabolism. Notably, a reduction in hepatic fat content and an improvement in hepatic insulin resistance are among the earliest beneficial effects of bariatric surgery, which has therefore emerged as an attractive treatment option for NAFLD. However, as the scope and popularity of weight loss surgery have expanded, new questions have arisen regarding its safety in patients with liver cirrhosis, the outcome of liver transplantation in patients with a history of bariatric surgery, and over incidental reports of liver failure following surgery. Studies in humans and rodents have also linked bariatric surgery to an increased risk of developing alcohol use disorder, a major risk factor for liver disease. This review integrates data from clinical and translational research to delineate both the beneficial impact of bariatric surgery on the liver and the potential risks involved.

Focal eosinophilic infiltration of the liver, benign or malignant?

Focal eosinophilic infiltration (FEI) of the liver shares imaging characteristics with malignant hepatic lesions but should be suspected when concomitantly observing eosinophilia. While in itself benign, the cause of FEI should be sought and treated.

The utility of biomarkers in prognosis assessment of patients with acute liver failure

BACKGROUND

Acute liver failure (ALF) is a rare but potential lethal condition characterized by the sudden development of jaundice, coagulopathy and hepatic encephalopathy in patients without underlying liver disease. In selected patients, emergency liver transplantation is required. Selection of these patients is based on clinical criteria such as the Kings College Criteria (KCC) or the Clichy criteria.

AIMS

The aim of this work is to provide an overview of potential biomarkers that could improve the prognostic value of KCC.

RESULTS

Several promising biomarkers involved in related pathophysiological processes have been identified. Some could be as stand-alone biomarkers; however, the best prognostic values have been observed in the combination of biomarkers with current models. Among these, the ALFSG Index that combines clinical parameters and circulating blood levels of CK18 claims a higher prognostic value than KCC.

CONCLUSIONS

In this review, all potential biomarkers for ALF have been summarized to give an overview of the work performed over the last years, and a glimpse of what to expect in this field in the coming years.

Histologically proven hepatic steatosis associates with lower testosterone levels in men with obesity

Men with obesity often present with low testosterone (T) and sex hormone-binding globulin (SHBG) levels. Several mechanisms for this have been proposed, but as SHBG is secreted by hepatocytes and sex steroids undergo hepatic metabolization, this study investigates whether severity and histological components of nonalcoholic fatty liver disease (NAFLD) are associated with sex steroid levels in obese men. This cross-sectional study included 80 obese men (age: 46 ± 11 years; body mass index: 42.2 ± 5.5 kg m⁻²). Serum levels of total T and estradiol (E₂) were measured using liquid chromatography coupled with tandem mass spectroscopy (LC/MS-MS) and SHBG and gonadotropins by immunoassay. Liver biopsies were evaluated using Steatosis, Activity, and Fibrosis scoring. Participants with steatohepatitis had similar median (1^st quartile–3^rd quartile) total T levels (7.6 [5.0–11.0] nmol l⁻¹ vs 8.2 [7.2–10.9] nmol l⁻¹; P = 0.147), lower calculated free T (cFT) levels (148.9 [122.9–188.8] pmol l⁻¹ vs 199.5 [157.3–237.6] pmol l⁻¹; P = 0.006), and higher free E₂/T ratios (10.0 [6.4–13.9] x10^-3 vs 7.1 [5.7–10.7] x10^-3; P = 0.026) compared to men with only nonalcoholic fatty liver. Among the histological components of NAFLD, only steatosis was independently associated with total T (r_s = −0.331, P = 0.003) and cFT levels (r_s = −0.255, P = 0.025). Obese men with steatohepatitis have even lower cFT levels compared to those without, an association mainly driven by grade of steatosis. Whether this reflects a subgroup of men with a more severe obesity-related phenotype or results from direct relations between hepatic steatosis and sex steroid metabolism needs further investigation.

Metallothioneins alter macrophage phenotype and represent novel therapeutic targets for acetaminophen-induced liver injury

Acetaminophen (APAP) intoxication is the foremost cause of drug-induced liver failure in developed countries. The only pharmacologic treatment option, N-acetylcysteine (NAC), is not effective for patients who are admitted too late and/or who have excessive liver damage, emphasizing the need for alternative treatment options. APAP intoxication results in hepatocyte death and release of danger signals, which further contribute to liver injury, in part by hepatic monocyte/macrophage infiltration and activation. Metallothionein (MT) 1 and 2 have important danger signaling functions and might represent novel therapeutic targets in APAP overdose. Therefore, we evaluated hepatic MT expression and the effect of anti-MT antibodies on the transcriptional profile of the hepatic macrophage population and liver injury following APAP overdose in mice. Hepatic MT expression was significantly induced in APAP-intoxicated mice and abundantly present in human livers. APAP intoxication in mice resulted in increased serum transaminase levels, extended necrotic regions on liver histology and induced expression of proinflammatory markers, which was significantly less pronounced in mice treated with anti-MT antibodies. Anti-MT antibody therapy attenuated proinflammatory macrophage polarization, as demonstrated by RNA sequencing analyses of isolated liver macrophages and in LPS-stimulated bone marrow-derived macrophages. Importantly, NAC and anti-MT antibodies were equally effective whereas administration of anti-MT antibody in combination with NAC exceeded the efficiency of both monotherapies in APAP-induced liver injury (AILI). We conclude that the neutralization of secreted MTs using a monoclonal antibody is a novel therapeutic strategy as mono- or add-on therapy for AILI. In addition, we provide evidence suggesting that MTs in the extracellular environment are involved in macrophage polarization.

NOX1 inhibition attenuates the development of a pro-tumorigenic environment in experimental hepatocellular carcinoma

Background

The poor prognosis of advanced HCC and limited efficacy of current systemic treatments emphasize the need for new or combined targeted therapies. The development of HCC is a multistage process in which liver injury appears in a complex microenvironment associated with oxidative stress. NOX enzymes are the main source of ROS during hepatocarcinogenesis and NOX1 in particular has shown correlation with poor prognosis of HCC patients. This study evaluates the effect of pharmacological NOX1 inhibition on the development and progression of HCC and its effect on the tumor microenvironment.

Methods

The in vitro cytotoxic effects of the NOX1 inhibitor GKT771 (Genkyotex) on human Huh7 and Hep3B and murine Hepa1-6 HCC cell lines, the human THP1 monocyte cell line and mouse macrophages were evaluated via MTT, LDH activity and CaspGlo® assays. In order to induce in vivo HCC, male SV129 wild-type mice received weekly IP injections of diethylnitrosamine (DEN) (35 mg/kg) for 20–25 weeks. Mice were treated with vehicle or GKT771 (30 mg/kg) via oral gavage, daily or twice daily, in preventive and therapeutic studies. The liver damage was evaluated for inflammation, angiogenesis, fibrosis and HCC development via histology, RT-qPCR, multiplex analyses and ROS levels.

Results

A concentration-dependent reduction in cellular activity of the human HCC cell lines without cytotoxicity was observed. GKT771 treatment reduced LPS-induced pro-inflammatory bone-marrow derived macrophage polarization. DEN injections resulted in 100 % tumor formation and the induction of HCC markers which could be reduced by twice daily dosing of GKT771 at early onset of advanced HCC. DEN-induced HCC resulted in an upregulation of pro-inflammatory, angiogenic and fibrotic markers which was less pronounced in GKT771 treated mice in all treatment regimens. In line, liver fibrosis was induced in HCC mice and this to a lesser extend upon GKT771 treatment.

Conclusions

NOX1 inhibition showed to be safe and well tolerated and was able to attenuate the induction of a pro-inflammatory, angiogenic and pro-fibrotic microenvironment suggesting that this might be a promising adjuvant therapeutic strategy in the treatment of advanced HCC.

Effect of isoform-specific HIF-1α and HIF-2α antisense oligonucleotides on tumorigenesis, inflammation and fibrosis in a hepatocellular carcinoma mouse model

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. For advanced HCC, there is still an unmet need for more effective therapeutic strategies. HCC is typically associated with hypoxia and the hypoxia-inducible factor (HIF) regulatory pathway plays an important role in HCC development and progression. Therefore, we investigated the therapeutic potential of isoform-specific HIF-1α and HIF-2α antisense oligonucleotides (ASOs), along with their effect on the inflammatory and fibrotic component of the tumor microenvironment (TME), in an experimental HCC mouse model. Based on its efficacy and safety, a dosage regimen of 20 mg/kg intraperitoneal injection of HIFα ASO twice per week was selected for further investigation in a preventive and therapeutic setting in a N,N-diethylnitrous amide (DEN)-induced HCC mouse model. DEN administration resulted in 100% tumor formation and HIFα ASO administration led to effective and selective hepatic downregulation of its target genes. HIFα ASO treatment had no effect on tumor numbers, but even enhanced the increased hepatic expression of HCC tumor markers, α-fetoprotein and glypican-3, compared to scrambled control ASO treatment in HCC mice. Especially HIF-1α ASO treatment resulted in an enhanced increase of monocytes and monocyte-derived macrophages in the liver and an enhanced hepatic upregulation of inflammatory markers. Both HIFα ASOs aggravated liver fibrosis in HCC mice compared to scrambled ASO treatment. The observed effects of our dosing regimen for HIF-1α and HIF-2α ASO treatment in the DEN-induced HCC mouse model discourage the use of HIFα isoforms as targets for the treatment of HCC.

Vasomodulators and Liver Transplantation for Portopulmonary Hypertension: Evidence From a Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

Untreated portopulmonary hypertension (PoPH) carries a poor prognosis. Previous reports have described vasomodulator (VM) therapy and liver transplantation (LT) as treatment options. We aimed to provide summary estimates on the endpoints of pulmonary hemodynamics and survival in patients with PoPH, treated with different modalities.

APPROACH AND RESULTS

We performed a systematic review with meta-analysis of mainly observational and case-control studies describing no treatment, VM, LT, or VM + LT in patients with PoPH. Twenty-six studies (1,019 patients) were included. Both VM and VM + LT improve pulmonary hemodynamics. A substantial proportion of patients treated with VM become eligible for LT (44%; 95% confidence interval [CI], 31-58). Pooled estimates for 1-, and 3-year postdiagnosis survival in patients treated with VM were 86% (95% CI, 81-90) and 69% (95% CI, 50-84) versus 82% (95% CI, 52-95) and 67% (95% CI, 53-78) in patients treated with VM + LT. Of note, studies reporting on the effect of VM mainly included Child-Pugh A/B patients, whereas studies reporting on VM + LT mainly included Child-Pugh B/C. Seven studies (238 patients) included both patients who received VM only and patients who received VM + LT. Risk of death in VM-only-treated patients was significantly higher than in patients who could be transplanted as well (odds ratio, 3.5; 95% CI, 1.4-8.8); however, importantly, patients who proceeded to transplant had been selected very strictly. In 50% of patients, VM can be discontinued post-LT (95% CI, 38-62).

CONCLUSIONS

VM and VM + LT both improve pulmonary hemodynamics and prognosis in PoPH. In a strictly selected subpopulation of cases where LT is indicated based on severe liver disease and where LT is considered safe and feasible, treatment with VM + LT confers a better prognosis. Considering successful VM, 44% can proceed to LT, with half being able to postoperatively stop medication.

Up to 50% of portal vein thrombosis remains undiagnosed until liver transplantation

BACKGROUND

Impact of portal vein thrombosis (PVT) on the clinical course in liver transplant candidates remains unclear. This study aims to identify prevalence and risk factors for PVT, assess outcome after liver transplantation (LT) in patients with PVT and study the effect of anticoagulation.

METHODS

This single-center retrospective cohort study was performed from January 2006 until June 2016. Patients were stratified according to presence of PVT. Risk factors and outcome were assessed using logistic regression and survival analysis.

RESULTS

Among 390 adults who underwent orthotopic LT, PVT occurred in 40 (10.3%). In, respectively, 10 (25%), 7 (17.5%), and 23 (57.5%) patients, PVT was identified at time of evaluation for transplantation, on the waiting list and during transplantation. A beneficial trend was present favoring the use of anticoagulation for PVT resolution (n = 3/7 vs 0/9; p = .062). Patient and graft survival were similar between the groups after a median follow-up of 5 years. However, 1-year patient survival was significantly lower (p = .031) in patients with PVT.

CONCLUSION

Portal vein thrombosis occurred in 10% of patients awaiting LT was undiagnosed in 50% until moment of LT and had a deleterious effect on 1-year survival. Anticoagulation showed a beneficial trend on recanalization of PVT and survival rate.

Differential effects of selective- and pan-PPAR agonists on experimental steatohepatitis and hepatic macrophages☆

BACKGROUND & AIMS

Peroxisome proliferator-activated receptors (PPARs) are essential regulators of whole-body metabolism, but also modulate inflammation in immune cells, notably macrophages. We compared the effects of selective PPAR agonists to those of the pan-PPAR agonist lanifibranor in non-alcoholic fatty liver disease (NAFLD), and studied isoform-specific effects on hepatic macrophage biology.

METHODS

Lanifibranor or selective PPARα (fenofibrate), PPARγ (pioglitazone) and PPARδ (GW501516) agonists were therapeutically administered in choline-deficient, amino acid-defined high-fat diet (CDAA-HFD)- and Western diet (WD)-fed mouse models of NAFLD. Acute liver injury was induced by carbon tetrachloride (CCl4). The role of PPARs on macrophage functionality was studied in isolated hepatic macrophages, bone marrow-derived macrophages stimulated with palmitic acid, and circulating monocytes from patients with NAFLD.

RESULTS

Lanifibranor improved all histological features of steatohepatitis in CDAA-HFD-fed mice, including liver fibrosis, thereby combining and exceeding specific effects of the single PPAR agonists. Its potent anti-steatotic efficacy was confirmed in a 3D liver biochip model with primary cells. Infiltrating hepatic monocyte-derived macrophages were reduced following PPAR agonist administration, especially with lanifibranor, even after short-term treatment, paralleling improved steatosis and hepatitis. Lanifibranor similarly decreased steatosis, liver injury and monocyte infiltration in the WD model. In the acute CCl4 model, neither single nor pan-PPAR agonists directly affected monocyte recruitment. Hepatic macrophages isolated from WD-fed mice displayed a metabolically activated phenotype. Lanifibranor attenuated the accompanying inflammatory activation in both murine palmitic acid-stimulated bone marrow-derived macrophages, as well as patient-derived circulating monocytes, in a PPARδ-dependent fashion.

CONCLUSION

Pan-PPAR agonists combine the beneficial effects of selective PPAR agonists and may counteract inflammation and disease progression more potently. PPARδ agonism and lanifibranor directly modulate macrophage activation, but not infiltration, thereby synergizing with beneficial metabolic effects of PPARα/γ agonists.

LAY SUMMARY

Peroxisome proliferated-activated receptors (PPARs) are essential regulators of metabolism and inflammation. We demonstrated that the pan-PPAR agonist lanifibranor ameliorated all aspects of non-alcoholic fatty liver disease in independent experimental mouse models. Non-alcoholic fatty liver disease and fatty acids induce a specific polarization status in macrophages, which was altered by lanifibranor to increase expression of lipid handling genes, thereby decreasing inflammation. PPAR isoforms have differential therapeutic effects on fat-laden hepatocytes, activated hepatic stellate cells and inflammatory macrophages, supporting the clinical development of pan-PPAR agonists.

Myeloid-specific IRE1alpha deletion reduces tumour development in a diabetic, non-alcoholic steatohepatitis-induced hepatocellular carcinoma mouse model

BACKGROUND AND AIMS

Obesity, diabetes and associated non-alcoholic steatohepatitis (NASH) are rising risk factors for hepatocellular carcinoma (HCC). Macrophages are important immune cells involved in inflammation and tumour development. Macrophage inositol-requiring enzyme 1 alpha (IRE1α), an ER-stress protein, has been shown to be involved in macrophage cytokine production, and myeloid-specific IRE1α knock-out (myeloid IRE1α-KO) mice showed reduced weight gain during high-fat diet feeding. However, the effect of myeloid IRE1α on NASH and subsequent HCC development has not been examined. Here, we characterized the transcriptional profile of the hepatic macrophage population in a diabetes-NASH-HCC mouse model, and investigated the effect of myeloid-specific IRE1α deletion on the phenotype of hepatic macrophage subsets and experimental NASH-HCC development.

METHODS

Mice with non-functional myeloid IRE1α were created by crossing Ire1a floxed mice with Lysm-Cre mice. Two-day old myeloid IRE1α-KO and wild type (WT) mice were subcutaneously injected with streptozotocin (STZ), and male mice were fed a high-fat, -sucrose, -cholesterol diet (Western diet, WD) from the age of 4 weeks until 21 weeks. Control myeloid IRE1α-KO and WT mice received a PBS injection and were fed a matched control diet. These mice were evaluated for obesity, diabetes, NASH and HCC. The hepatic macrophage population was evaluated by flow cytometry and RNA sequencing on FACS-isolated macrophage subsets.

RESULTS

STZ-injection and WD feeding resulted in an impaired glucose tolerance, advanced NASH with fibrosis, and HCC development. Myeloid IRE1α-KO STZ mice showed lower fasting glucose levels at the start of WD feeding, and an improved glucose tolerance and attenuated HCC development after 17 weeks of WD feeding despite a similar degree of liver steatosis and inflammation compared to WT mice. Transcriptomic analysis of WT liver Kupffer cells, macrophages and monocytes revealed phenotypical changes in those cell subsets during NASH-HCC development. Isolated liver Kupffer cells and macrophages from mice with a myeloid IRE1α deletion showed downregulated pathways involved in immune system activation and metabolic pathways (only in Kupffer cells), whereas pathways involved in cell division and metabolism were upregulated in monocytes. These transcriptional differences were attenuated during NASH-HCC development.

CONCLUSION

Our results show that myeloid-specific IRE1α deletion results in an altered transcriptional profile of hepatic macrophages and dampens diabetes-induced NASH-HCC development, possibly by attenuated diabetes induction.

Angiogenesis in the progression of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide, and an increasing cause of liver cirrhosis and hepatocellular carcinoma. Angiogenesis, the formation of new blood vessels from pre-existing ones, is a key pathophysiological mechanism contributing to NAFLD progression. Major triggers for angiogenesis in NAFLD include tissue hypoxia, structural and dynamic endothelial cell dysfunction, stellate cell activation and macrophage-mediated inflammation. In turn, angiogenesis drives inflammation and is closely linked to the progression of liver fibrosis and the development of liver cancer. In particular, the molecular crosstalk between pro-angiogenic endothelial cells and activated stellate cells can result in a positive feedback loop in which angiogenesis and fibrosis develop in parallel. In this review, we highlight the molecular mechanisms, drivers and consequences of angiogenesis in the progression of NAFLD to NASH, fibrosis and hepatocellular carcinoma. Evidence from animal and clinical studies suggests that mediators of angiogenesis and endothelial dysfunction are promising disease biomarkers, and that inhibiting angiogenesis may improve the course of NAFLD.

Combination of sivelestat and N-acetylcysteine alleviates the inflammatory response and exceeds standard treatment for acetaminophen-induced liver injury

Hepatocyte death during acetaminophen (APAP) intoxication elicits a reactive inflammatory response, with hepatic recruitment of neutrophils and monocytes, which further aggravates liver injury. Neutrophil elastase (NE), secreted by activated neutrophils, carries degradative and cytotoxic functions and maintains a proinflammatory state. We investigated NE as a therapeutic target in acetaminophen-induced liver injury (AILI). C57BL/6 mice were administered a toxic dose of APAP, 2 h prior to receiving the NE inhibitor sivelestat, N-acetylcysteine (NAC), or a combination therapy, and were euthanized after 24 and 48 h. Upon APAP overdose, neutrophils and monocytes infiltrate the injured liver, accompanied by increased levels of NE. Combination therapy of NAC and sivelestat significantly limits liver damage, as evidenced by lower serum transaminase levels and less hepatic necrosis compared to mice that received APAP only, and this to a greater extent than NAC monotherapy. Lower hepatic expression of proinflammatory markers was observed in the combination treatment group, and flow cytometry revealed significantly less monocyte influx in livers from mice treated with the combination therapy, compared to untreated mice and mice treated with NAC only. The potential of NE to induce leukocyte migration was confirmed in vitro. Importantly, sivelestat did not impair hepatic repair. In conclusion, combination of NE inhibition with sivelestat and NAC dampens the inflammatory response and reduces liver damage following APAP overdose. This strategy exceeds the standard of care and might represent a novel therapeutic option for AILI.

Insulin resistance associates with hepatic lobular inflammation in subjects with obesity

PURPOSE

Obese subjects with nonalcoholic fatty liver disease (NAFLD) are more prone to develop additional metabolic disturbances such as systemic insulin resistance (IR) and type 2 diabetes. NAFLD is defined by hepatic steatosis, lobular inflammation, ballooning and stage of fibrosis, but it is unclear if and which components could contribute to IR.

OBJECTIVE

To assess which histological components of NAFLD associate with IR in subjects with obesity, and if so, to what extent.

METHODS

This cross-sectional study included 78 obese subjects (mean age 46 ± 11 years; BMI 42.2 ± 4.7 kg/m2). Glucose levels were analysed by hexokinase method and insulin levels with electrochemiluminescence. Homeostasis model assessment-estimated insulin resistance (HOMA-IR) was calculated. Liver biopsies were evaluated for histological components of NAFLD.

RESULTS

A positive association between overall NAFLD Activity Score and HOMA-IR was found (r s = 0.259, P = 0.022). As per individual components, lobular inflammation and fibrosis stage were positively associated with HOMA-IR, glucose and insulin levels (P < 0.05), and HOMA-IR was higher in patients with more inflammatory foci or higher stage of fibrosis. These findings were independent of age, BMI, triglyceride levels, diabetes status and sex (all P < 0.043). In a combined model, lobular inflammation, but not fibrosis, remained associated with HOMA-IR.

CONCLUSION

In this group of obese subjects, a major contributing histological component of NAFLD to the relation between NAFLD severity and IR seems to be the grade of hepatic lobular inflammation. Although no causal relationship was assessed, preventing or mitigating this inflammatory response in obesity might be of importance in controlling obesity-related metabolic disturbances.

Update on liver transplantation for cholangiocarcinoma : a review of the recent literature

Cholangiocarcinoma (CC) represent 3% of all gastrointestinal tumours and can be classified anatomically in 3 types: intrahepatic (ICC), perihilar (PCC) and distal (DCC) cholangiocarcinomas. Resection is the treatment of choice but is only achieved in a few cases (<20%) because of invasion of the biliary tract and/or vascular structures. The outcome of advanced CC is poor with an overall survival (OS) of maximum 15 months with chemotherapy. In the 1990s, CC was regarded as a contraindication for liver transplantation (LT). LT has recently been proposed as potentially curative option for ICC and PCC. Careful patient selection has changed OS. This article provides an update on current status of LT for patients with unresectable CC.

The potential of glycomics as prognostic biomarkers in liver disease and liver transplantation

The study of glycomics is a novel and fascinating approach for the development of biomarkers. It has become clear that in the field of liver disease specific glycomic patters are present in specific disease states, which has led to the development of diagnostic biomarkers. In this manuscript, we will describe two new applications of this technology for the development of prognostic biomarkers. The first biomarker is associated with the risk of hepatocellular carcinoma development in patients with compensated cirrhosis. The second biomarker is present in perfusate and is related to the risk of primary non function occurrence after liver transplantation. The technology used for these biomarkers could easily be implemented on routine capillary electrophoresis equipment.

Angiopoietin-2 Promotes Pathological Angiogenesis and Is a Therapeutic Target in Murine Nonalcoholic Fatty Liver Disease

Angiogenesis contributes to the development of nonalcoholic steatohepatitis (NASH) and promotes inflammation, fibrosis, and progression to hepatocellular carcinoma (HCC). Angiopoietin-2 (Ang-2) is a key regulator of angiogenesis. We aimed to investigate the role of Ang-2 and its potential as a therapeutic target in NASH using human samples, in vivo mouse models, and in vitro assays. Serum Ang-2 levels were determined in 104 obese patients undergoing bariatric surgery and concomitant liver biopsy. The effect of the Ang-2/Tie2 receptor inhibiting peptibody L1-10 was evaluated in the methionine-choline deficient (MCD) and streptozotocin-western diet nonalcoholic fatty liver disease mouse models, and in vitro on endothelial cells and bone marrow-derived macrophages. The hepatic vasculature was visualized with µCT scans and scanning electron microscopy of vascular casts. Serum Ang-2 levels were increased in patients with histological NASH compared with patients with simple steatosis and correlated with hepatic CD34 immunoreactivity as a marker of hepatic angiogenesis. Serum and hepatic Ang-2 levels were similarly increased in mice with steatohepatitis. Both preventive and therapeutic L1-10 treatment reduced hepatocyte ballooning and fibrosis in MCD diet-fed mice and was associated with reduced hepatic angiogenesis and normalization of the vascular micro-architecture. Liver-isolated endothelial cells and monocytes from MCD-fed L1-10-treated mice showed reduced expression of leukocyte adhesion and inflammatory markers, respectively, compared with cells from untreated MCD diet-fed mice. In the streptozotocin-western diet model, therapeutic Ang-2 inhibition was able to reverse NASH and attenuate HCC progression. In vitro, L1-10 treatment mitigated increased cytokine production in lipopolysaccharide-stimulated endothelial cells but not in macrophages. Conclusion: Our findings provide evidence for Ang-2 inhibition as a therapeutic strategy to target pathological angiogenesis in NASH.