Natural history of NASH and HCC

Gut microbiota-lncRNA/circRNA crosstalk: implications for different diseases

The gut microbiota features an abundance of diverse microorganisms and represents an important component of human physiology and metabolic homeostasis, indicating their roles in a wide array of physiological and pathological processes in the host. Maintaining balance in the gut microbiota is critical for normal functionality as microbial dysbiosis can lead to the occurrence and development of diseases through various mechanisms. Long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) are non-coding RNAs that perform important regulatory functions for many processes. Furthermore, the gut microbiota and lncRNAs/circRNAs are known to interact in a range of both physiological and pathological activities. In this article, we review existing research relevant to the interaction between the gut microbiota and lncRNAs/circRNAs and investigate the role of their crosstalk in the pathogenesis of different diseases. Studies have shown that, the gut microbiota can target lncRNAs ENO1-IT1, BFAL1, and LINC00152 to regulate colorectal cancer development via various signaling pathways. In addition, the gut microbiota can influence mental diseases and lung tumor metastasis by modulating circRNAs such as circNF1-419, circ_0001239, circHIPK2 and mmu_circ_0000730. These findings provide a theoretical basis for disease prevention and treatment and suggest that gut microbiota-lncRNA/circRNA crosstalk has high clinical value.

Metabolic dysfunction-associated steatotic liver disease in adults

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the umbrella term that comprises metabolic dysfunction-associated steatotic liver, or isolated hepatic steatosis, through to metabolic dysfunction-associated steatohepatitis, the progressive necroinflammatory disease form that can progress to fibrosis, cirrhosis and hepatocellular carcinoma. MASLD is estimated to affect more than one-third of adults worldwide. MASLD is closely associated with insulin resistance, obesity, gut microbial dysbiosis and genetic risk factors. The obesity epidemic and the growing prevalence of type 2 diabetes mellitus greatly contribute to the increasing burden of MASLD. The treatment and prevention of major metabolic comorbidities such as type 2 diabetes mellitus and obesity will probably slow the growth of MASLD. In 2023, the field decided on a new nomenclature and agreed on a set of research and action priorities, and in 2024, the US FDA approved the first drug, resmetirom, for the treatment of non-cirrhotic metabolic dysfunction-associated steatohepatitis with moderate to advanced fibrosis. Reliable, validated biomarkers that can replace histology for patient selection and primary end points in MASH trials will greatly accelerate the drug development process. Additionally, noninvasive tests that can reliably determine treatment response or predict response to therapy are warranted. Sustained efforts are required to combat the burden of MASLD by tackling metabolic risk factors, improving risk stratification and linkage to care, and increasing access to therapeutic agents and non-pharmaceutical interventions.

Role of noninvasive tests on the prediction of hepatocellular carcinoma in nonalcoholic fatty liver disease patients without cirrhosis: a systematic review and meta-analysis of aggregate and individual patient data

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has been identified as an emerging risk factor for hepatocellular carcinoma (HCC). Identifying non-cirrhotic NAFLD patients at risk for HCC is crucial. We aimed to investigate the utility of noninvasive tests (NITs) as predictors for HCC and to determine optimal and cost-effective NIT cutoffs for HCC surveillance in non-cirrhotic NAFLD patients.

METHODS

Medline, EMBASE, and Scopus databases were searched for studies evaluating the relationship between NITs and HCC in this population. Random-effects models were used to estimate hazard ratios or risk ratios and 95% confidence interval (95% CI). Cutoffs of NITs for identifying high-risk patients for HCC were determined.

RESULTS

This systematic review comprised 20 studies. A meta-analysis of 379 194 patients was conducted using six studies with individual patient data and five studies with aggregate data. Among NITs studied, fibrosis-4 index (FIB-4), aspartate aminotransferase to platelet ratio index (APRI), and NAFLD fibrosis score (NFS) were significantly associated with HCC, with pooled risk ratio (95% CI) of 9.21 (5.79-14.64), pooled hazard ratio of 12.53 (6.57-23.90), and 13.32 (6.48-27.37), respectively. FIB-4, APRI, and NFS of more than 2.06, 0.65, and 0.51 resulted in the highest area under the receiver operating characteristics of 0.83, 0.80, and 0.85, respectively. Surveillance in patients with FIB-4 ≥ 5.91 and NFS ≥ 2.85 would be cost-effective with an annual HCC incidence of ≥15 per 1000 patient-years.

CONCLUSION

FIB-4, APRI, and NFS are associated with HCC development in non-cirrhotic NAFLD patients. Different NIT cutoffs may be used to enroll high-risk NAFLD patients for HCC surveillance, according to resource availability in different settings.

Contribution of extracellular vesicles to steatosis-related liver disease and their therapeutic potential

Extracellular vesicles (EVs) are small particles released by many cell types in different tissues, including the liver, and transfer specific cargo molecules from originating cells to receptor cells. This process generally culminates in activation of distant cells and inflammation and progression of certain diseases. The global chronic liver disease (CLD) epidemic is estimated at 1.5 billion patients worldwide. Cirrhosis and liver cancer are the most common risk factors for CLD. However, hepatitis C and B virus infection and obesity are also highly associated with CLD. Nonetheless, the etiology of many CLD pathophysiological, cellular, and molecular events are unclear. Changes in hepatic lipid metabolism can lead to lipotoxicity events that induce EV release. Here, we aimed to present an overview of EV features, from definition to types and biogenesis, with particular focus on the molecules related to steatosis-related liver disease, diagnosis, and therapy.

Neutrophil extracellular traps in homeostasis and disease

Neutrophil extracellular traps (NETs), crucial in immune defense mechanisms, are renowned for their propensity to expel decondensed chromatin embedded with inflammatory proteins. Our comprehension of NETs in pathogen clearance, immune regulation and disease pathogenesis, has grown significantly in recent years. NETs are not only pivotal in the context of infections but also exhibit significant involvement in sterile inflammation. Evidence suggests that excessive accumulation of NETs can result in vessel occlusion, tissue damage, and prolonged inflammatory responses, thereby contributing to the progression and exacerbation of various pathological states. Nevertheless, NETs exhibit dual functionalities in certain pathological contexts. While NETs may act as autoantigens, aggregated NET complexes can function as inflammatory mediators by degrading proinflammatory cytokines and chemokines. The delineation of molecules and signaling pathways governing NET formation aids in refining our appreciation of NETs' role in immune homeostasis, inflammation, autoimmune diseases, metabolic dysregulation, and cancer. In this comprehensive review, we delve into the multifaceted roles of NETs in both homeostasis and disease, whilst discussing their potential as therapeutic targets. Our aim is to enhance the understanding of the intricate functions of NETs across the spectrum from physiology to pathology.

Habitual use of glucosamine and adverse liver outcomes among patients with type 2 diabetes and MASLD

BACKGROUND

Glucosamine is a dietary supplement commonly used to support joint health. However, there has been interest in exploring other effects of glucosamine on health outcomes due to its ant-inflammation effect.

OBJECTIVE

This study compared the risks of major adverse liver outcomes (MALOs) between regular users and non-users of glucosamine among patients with type 2 diabetes and metabolic dysfunction associated steatotic liver disease (MASLD) using the data from a large prospective cohort study.

METHODS

Demographic, anthropometric, laboratory and medication prescription information among 18 753 patients with type 2 diabetes and MASLD was obtained from the UK Biobank. MASLD was identified based on hepatic steatosis defined by fatty liver index ≥60 plus the presence of any clues of metabolic dysregulation and cardio-metabolic risk factors, excluding patients with moderate to severe alcohol consumption.

RESULTS

During a mean follow-up of 11.4 years, 826 incident MALOs events were recorded. Patients not regularly using glucosamine compared with patients using glucosamine showed a significantly higher risk of the composite MALOs (HR 1.36, 95% confidence interval [CI] 1.09-1.69) as well as most individual MALOs except for ascites. The multivariable-adjusted HRs of MALOs within 3, 5 and 10 years among non-users of glucosamine compared with regular users were 1.79 (95% CI .69-2.03), 1.88 (95% CI 1.21-2.54) and 1.32 (95% CI 1.05-1.72), respectively. Further subgroup analyses in participants with different baseline characteristics and sensitivity analyses excluding participants who regularly took any other supplements and participants who used self-reports to diagnose diabetes confirmed the findings.

CONCLUSIONS

The present study indicated that habitual use of glucosamine was associated with a low risk of individual and composite MALOs among patients with type 2 diabetes and MASLD.

Quantifying the natural growth rate of hepatocellular carcinoma: A real-world retrospective study in southwestern China

BACKGROUND

In recent years, approximately half of the newly diagnosed cases and mortalities attributed to hepatocellular carcinoma (HCC) have been reported in China. Despite the high incidence of HCC, there remains a paucity of data regarding the natural growth pattern and the determination of optimal surveillance intervals specific to the Chinese population.

AIM

To quantify the natural tumor growth pattern of HCC in regional China.

METHODS

A retrospective analysis was performed on patients from a single institution in Southwest China who had undergone two or more serial dynamic computed tomography or magnetic resonance imaging scans between 2014 and 2020, without having received any anti-cancer therapy. Tumor growth was assessed using tumor volume doubling time (TVDT) and tumor growth rate (TGR), with volumes measured manually by experienced radiologists. Simple univariate linear regression and descriptive analysis were applied to explore associations between growth rates and clinical factors.

RESULTS

This study identifies the median TVDT for HCC as 163.4 d, interquartile range (IQR) 72.1 to 302.3 d, with a daily TGR of 0.42% (IQR 0.206%-0.97%). HCC growth patterns reveal that about one-third of tumors grow indolently with TVDT exceeding 270 d, another one-third of tumors exhibit rapid growth with TVDT under 90 d, and the remaining tumors show intermediate growth rates, with TVDT ranging between 3 to 9 months.

CONCLUSION

The identified TGRs support biannual surveillance and follow-up for HCC patients in certain regions of China. Given the observed heterogeneity in HCC growth, further investigation is warranted.

From NAFLD to NASH: Understanding the spectrum of non-alcoholic liver diseases and their consequences

Non-alcoholic fatty liver disease (NAFLD) has become one of the most frequent chronic liver diseases worldwide in recent decades. Metabolic diseases like excessive blood glucose, central obesity, dyslipidemia, hypertension, and liver function abnormalities cause NAFLD. NAFLD significantly increases the likelihood of liver cancer, heart disease, and mortality, making it a leading cause of liver transplants. Non-alcoholic steatohepatitis (NASH) is a more advanced form of the disease that causes scarring and inflammation of the liver over time and can ultimately result in cirrhosis and hepatocellular carcinoma. In this review, we briefly discuss NAFLD's pathogenic mechanisms, their progression into NASH and afterward to NASH-related cirrhosis. It also covers disease epidemiology, metabolic mechanisms, glucose and lipid metabolism in the liver, macrophage dysfunction, bile acid toxicity, and liver stellate cell stimulation. Additionally, we consider the contribution of intestinal microbiota, genetics, epigenetics, and ecological factors to fibrosis progression and hepatocellular carcinoma risk in NAFLD and NASH patients.

Matrix viscoelasticity promotes liver cancer progression in the pre-cirrhotic liver

Type 2 diabetes mellitus is a major risk factor for hepatocellular carcinoma (HCC). Changes in extracellular matrix (ECM) mechanics contribute to cancer development1,2, and increased stiffness is known to promote HCC progression in cirrhotic conditions3,4. Type 2 diabetes mellitus is characterized by an accumulation of advanced glycation end-products (AGEs) in the ECM; however, how this affects HCC in non-cirrhotic conditions is unclear. Here we find that, in patients and animal models, AGEs promote changes in collagen architecture and enhance ECM viscoelasticity, with greater viscous dissipation and faster stress relaxation, but not changes in stiffness. High AGEs and viscoelasticity combined with oncogenic β-catenin signalling promote HCC induction, whereas inhibiting AGE production, reconstituting the AGE clearance receptor AGER1 or breaking AGE-mediated collagen cross-links reduces viscoelasticity and HCC growth. Matrix analysis and computational modelling demonstrate that lower interconnectivity of AGE-bundled collagen matrix, marked by shorter fibre length and greater heterogeneity, enhances viscoelasticity. Mechanistically, animal studies and 3D cell cultures show that enhanced viscoelasticity promotes HCC cell proliferation and invasion through an integrin-β1-tensin-1-YAP mechanotransductive pathway. These results reveal that AGE-mediated structural changes enhance ECM viscoelasticity, and that viscoelasticity can promote cancer progression in vivo, independent of stiffness.

Liver fibrosis in NAFLD/NASH: from pathophysiology towards diagnostic and therapeutic strategies

Liver fibrosis, as an excess deposition of extracellular matrix (ECM) components, results from chronic liver injury as well as persistent activation of inflammatory response and of fibrogenesis. Liver fibrosis is a major determinant for chronic liver disease (CLD) progression and in the last two decades our understanding on the major molecular and cellular mechanisms underlying the fibrogenic progression of CLD has dramatically improved, boosting pre-clinical studies and clinical trials designed to find novel therapeutic approaches. From these studies several critical concepts have emerged, starting to reveal the complexity of the pro-fibrotic microenvironment which involves very complex, dynamic and interrelated interactions between different hepatic and extrahepatic cell populations. This review will offer first a recapitulation of established and novel pathophysiological basic principles and concepts by intentionally focus the attention on NAFLD/NASH, a metabolic-related form of CLD with a high impact on the general population and emerging as a leading cause of CLD worldwide. NAFLD/NASH-related pro-inflammatory and profibrogenic mechanisms will be analysed as well as novel information on cells, mediators and signalling pathways which have taken advantage from novel methodological approaches and techniques (single cell genomics, imaging mass cytometry, novel in vitro two- and three-dimensional models, etc.). We will next offer an overview on recent advancement in diagnostic and prognostic tools, including serum biomarkers and polygenic scores, to support the analysis of liver biopsies. Finally, this review will provide an analysis of current and emerging therapies for the treatment of NAFLD/NASH patients.

Combined with multiplex and network analysis to reveal the key genes and mechanisms of nonalcoholic fatty liver disease

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) has become a significant cause of chronic liver disease in developed countries, as a result of the worldwide trend of obesity and associated metabolic syndrome. Obesity and high-fat diet (HFD) are very common in patients with NAFLD. However, how to screen out key differentially expressed genes (DEGs) is a challenging task. The purpose of this study is to study the screen of key genes and pathways of HFD on the formation process of non-alcoholic fatty liver through network pharmacological analysis.

METHODS

In this study, 173 genes associated with NAFLD were collected from the Gene Expression Omnibus (GEO) database. To find significant genes and pathways, combine network clustering analysis, topology analysis, and pathway analysis.

RESULTS

The results showed that there were four key signaling pathways related to HFD, including complement cascade, Atorvastatin ADME, Asthma and Aflatoxin activation and detoxification. In addition, we identified six representative key genes, including Ccl5, Tlr2, Cd274, Cxcl10, Cxcl9 and Cd74, and screened three intersecting genes in Mus musculus and Homo sapiens sample, including C3, F2 and C7.

CONCLUSIONS

In conclusion, our study constructed the NAFLD gene regulatory network of C57BL/6J mice for the first time and jointly analyzed the Mus musculus samples and Homo sapiens samples. It provides new insights for identifying potential biomarkers and valuable therapeutic clues, and puts forward a new method for web-based research. These findings may provide potential targets for early diagnosis, effective therapy and prognostic markers of NAFLD.

Insight to the association among fibroblast growth factor 21, non-alcoholic fatty liver disease and cardiovascular outcomes: A population-based study

OBJECTIVE

We aimed to investigate whether there was a joint effect of fibroblast growth factor 21 (FGF21) and non-alcoholic fatty liver disease (NAFLD) or interaction on the incidence of cardiovascular diseases based on a community-dwelling population.

METHODS

Serum FGF21 levels were determined using an enzyme-linked immunosorbent method. NAFLD was diagnosed via ultrasonography. Multivariable-adjusted cox proportional hazards models were used to assess the joint effects of FGF21 and NAFLD on the major adverse cardiovascular events (MACE).

RESULTS

A total of 1194 participants were enrolled in the final analysis. The multivariable-adjusted hazard ratio (HR) of MACE was 1.84 (95% confidence interval (CI) 1.18-2.86) in participants with diagnosed NAFLD at baseline, compared with those without NAFLD at baseline. The multivariable-adjusted HRs of MACE across quintiles of serum FGF21 levels at baseline were 1.00, 1.48 (95%CI 0.68-3.21), 2.01 (95%CI 0.98-4.13), 1.94 (95%CI 0.94-4.02) and 2.14 (95%CI 1.03-4.44) respectively. Participants with high FGF21 levels and NAFLD at baseline showed the highest risk of MACE with a significant interaction between the presence of NAFLD and serum FGF21 levels.

CONCLUSIONS

Both FGF21 and NAFLD were associated with MACE, while the association between FGF21 and MACE may be interacted by the presence of NAFLD at baseline.

Clinical trials reimagined

Clinical trials have been a central driver of change and have provided the evidence base necessary to advance new therapies for liver diseases. This review provides a perspective on the status of trials in hepatology and a vantage point into the emerging capabilities and external forces that will shape the conduct of clinical trials in the future. The adaptations to clinical trial operations in response to the disruptions by the COVID-19 pandemic and opportunities for innovation in hepatology trials are emphasized. Future trials in hepatology will be driven by unmet therapeutic needs and fueled by technological advances incorporating digital capabilities with expanded participant-derived data collection, computing, and analytics. Their design will embrace innovative trial designs adapted to these advances and that emphasize broader and more inclusive participant engagement. Their conduct will be further shaped by evolving regulatory needs and the emergence of new stakeholders in the clinical trials ecosystem. The evolution of clinical trials will offer unique opportunities to advance new therapeutics that will ultimately improve the lives of patients with liver diseases.

Opportunities and considerations for studying liver disease with microphysiological systems on a chip

Advances in microsystem engineering have enabled the development of highly controlled models of the liver that better recapitulate the unique in vivo biological conditions. In just a few short years, substantial progress has been made in creating complex mono- and multi-cellular models that mimic key metabolic, structural, and oxygen gradients crucial for liver function. Here we review: 1) the state-of-the-art in liver-centric microphysiological systems and 2) the array of liver diseases and pressing biological and therapeutic challenges which could be investigated with these systems. The engineering community has unique opportunities to innovate with new liver-on-a-chip devices and partner with biomedical researchers to usher in a new era of understanding of the molecular and cellular contributors to liver diseases and identify and test rational therapeutic modalities.

Infectious Agents Induce Wnt/β-Catenin Pathway Deregulation in Primary Liver Cancers

Interaction between infectious agents and liver tissue, as well as repeated and extreme biological events beyond adaptive capacities, may result in pathological conditions predisposing people to development of primary liver cancers (PLCs). In adults, PLCs mainly comprise hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). Various infectious agents in the hepatic microenvironment can destabilize normal liver cell functions by modulating the Wnt/β-catenin pathway components. Among them, hepatotropic viruses B, C, and D are involved in Wnt/β-catenin signaling dysregulation. Other microbial agents, including oncogenic viruses such as Epstein-Barr virus (EBV) and human papilloma virus (HPV), bacteria, e.g., Mycoplasma hyorhinis and Salmonella Typhi, the protozoan parasite Toxoplasma gondii, the fungus Aspergillus flavus, and liver flukes such as Clonorchissinensis or Opisthorchis viverrini, may induce malignant transformation in hepatocytes or in target cells of the biliary tract through aberrant Wnt signaling activation. This review focuses on new insights into infectious agents implicated in the deregulation of Wnt signaling and PLC development. Since the Wnt/β-catenin pathway is a driver of cancer following viral and bacterial infections, molecules inhibiting the complex axis of Wnt signaling could represent novel therapeutic approaches in PLC treatment.

Non-target GC-MS analyses of fecal VOCs in NASH-hepatocellular carcinoma model STAM mice

The increased incidence of obesity in the global population has increased the risk of several chronic inflammation-related diseases, including non-alcoholic steatohepatitis (NASH)-hepatocellular carcinoma (HCC). The progression from NASH to HCC involves a virus-independent liver carcinogenic mechanism; however, we currently lack effective treatment and prevention strategies. Several reports have suggested that fecal volatile organic compounds (VOCs) are strongly associated with NASH-HCC; therefore, we explored the biomarkers involved in its pathogenesis and progression. Fecal samples collected from control and NASH-HCC model STAM mice were subjected to headspace autosampler gas chromatography-electron ionization-mass spectrometry. Non-target profiling analysis identified diacetyl (2,3-butandione) as a fecal VOC that characterizes STAM mice. Although fecal diacetyl levels were correlated with the HCC in STAM mice, diacetyl is known as a cytotoxic/tissue-damaging compound rather than genotoxic or mutagenic; therefore, we examined the effect of bioactivity associated with NASH progression. We observed that diacetyl induced several pro-inflammatory molecules, including tumor necrosis factor-α, cyclooxygenase-2, monocyte chemoattractant protein-1, and transforming growth factor-β, in mouse macrophage RAW264.7 and Kupffer KPU5 cells. Additionally, we observed that diacetyl induced α-smooth muscle actin, one of the hallmarks of fibrosis, in an ex vivo cultured hepatic section, but not in in vitro hepatic stellate TWNT-1 cells. These results suggest that diacetyl would be a potential biomarker of fecal VOC in STAM mice, and its ability to trigger the macrophage-derived inflammation and fibrosis may partly contribute to NASH-HCC carcinogenesis.

Persistent Lipid Accumulation Leads to Persistent Exacerbation of Endoplasmic Reticulum Stress and Inflammation in Progressive NASH via the IRE1α/TRAF2 Complex

Non-alcoholic steatohepatitis (NASH) is a metabolic disorder that often leads to other severe liver diseases, yet treatment options are limited. Endoplasmic reticulum (ER) stress is an important pathogenetic mechanism of NASH and plays a key role in tandem steatosis as well as liver inflammation. This study aims to develop a progressive NASH model through sustained lipid accumulation and to elucidate its molecular mechanism through IRE1α/TRAF2 complex. Male SD rats were fed a high-fat diet (HFD) for 4, 8, and 12 weeks to induce progressive NASH. MRNA sequencing and PPI analysis were used to screen core genes. Transmission electron microscopy, immunofluorescence staining, ELISA, qRT-PCR, and Western blotting were used at each time point to compare differences between each index of progressive NASH at 4, 8, and 12 weeks. Sustained lipid accumulation led to structural disruption of the ER, a reduction in ER number, and an increase of lipid droplet aggregation in hepatocytes. Persistent lipid accumulation led to a persistent increase in mRNA and protein expression of the IRE1α/TRAF2 complex, IKK/IκB/NF-κB signaling pathway and ASK1/JNK1 signaling pathway, and TNF-α, IL-1β, and IL-6 also continued to increase. Persistent lipid accumulation led to a persistent exacerbation of ER stress and inflammation in progressive NASH via the IRE1α/TRAF2 complex.

Meta-analysis: Enhanced liver fibrosis test to identify hepatic fibrosis in chronic liver diseases

BACKGROUND & AIMS

Patients with liver disease can be stratified for risk of liver-related ill health by degree of hepatic fibrosis. The Enhanced liver fibrosis (ELF) test was developed to quantify hepatic fibrosis non-invasively and is widely used. The objective of this review was to identify and synthesise the evidence on the diagnostic accuracy of the ELF test for staging of hepatic fibrosis.

APPROACH & RESULTS

Searches of PubMed and EMBASE were conducted between October 2020 and November 2021 to identify studies reporting the diagnostic accuracy of the ELF test compared to histology in liver disease patients. QUADAS-2 was used to assess risk of bias in each study. Meta-analysis using the multiple thresholds model described by Steinhauser S, Schumacher M, Rücker G. Modelling multiple thresholds in meta-analysis of diagnostic test accuracy studies. BMC Med. Res. Methodol. 2016;16. 10.1186/s12874-016-0196-1 allowed synthesis of 2 × 2 data at different cut-offs. Sixty-three studies were included in this review. These studies included 19,285 patients with or at risk of liver disease from viral hepatitis, Non-Alcoholic Fatty Liver Disease, Alcohol-related Liver Disease and other mixed chronic liver diseases. The prevalence of significant fibrosis, advanced fibrosis and cirrhosis was 47.5%, 39.2% and 4.4%, respectively. Cut-offs with maximal Youden index were generated with AUROC = 0.811 (95% CI: 0.736-0.870), 0.812 (95% CI: 0.758-0.856) and 0.810 (95% CI: 0.694-0.888) to detect significant fibrosis, advanced fibrosis or cirrhosis, respectively. Diagnostic accuracy of the ELF test varied between different liver diseases and cut-offs to detect each stage with 95% sensitivity or specificity were also generated.

CONCLUSIONS

Meta-analysis revealed considerable variability in the ability of ELF to stage fibrosis across disease aetiologies. Research has mostly focused on viral hepatitis and NAFLD. There is currently a lack of data on the value of the ELF test in Alcohol-related liver disease and patients in primary care settings.

Role of targeting TLR4 signaling axis in liver-related diseases

Toll-like receptor 4 (TLR4) plays an important role as a key signal-receiving transmembrane protein molecule in the liver, and substances that target the liver exert therapeutic effects via TLR4-related signaling pathways. This article provides a comprehensive review of targeting the TLR4 signaling axis to play an important role in the liver based on endogenous substances. Articles were divided into 5 major types of liver disease, acute liver injury, viral hepatitis, alcoholic and non-alcoholic liver disease, cirrhosis, and liver cancer, to elucidate how various endogenous substances affect the liver via the TLR4 pathway and the important role of the pathway itself in liver-related diseases to discover the potential therapeutic implications of the TLR4-related pathway in the liver. The results indicate that activation of the TLR4-related signaling axis primarily plays a role in promoting disease progression in liver-related diseases, and the TLR4/MyD88/NF-κB axis plays the most dominant role. Therefore, exploring the full effects of drugs targeting the TLR4-related signaling axis in the liver and the new use of old drugs may be a new research direction.

Immunometabolic factors contributing to obesity-linked hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major public health concern that is promoted by obesity and associated liver complications. Onset and progression of HCC in obesity is a multifactorial process involving complex interactions between the metabolic and immune system, in which chronic liver damage resulting from metabolic and inflammatory insults trigger carcinogenesis-promoting gene mutations and tumor metabolism. Moreover, cell growth and proliferation of the cancerous cell, after initiation, requires interactions between various immunological and metabolic pathways that provide stress defense of the cancer cell as well as strategic cell death escape mechanisms. The heterogenic nature of HCC in addition to the various metabolic risk factors underlying HCC development have led researchers to focus on examining metabolic pathways that may contribute to HCC development. In obesity-linked HCC, oncogene-induced modifications and metabolic pathways have been identified to support anabolic demands of the growing HCC cells and combat the concomitant cell stress, coinciding with altered utilization of signaling pathways and metabolic fuels involved in glucose metabolism, macromolecule synthesis, stress defense, and redox homeostasis. In this review, we discuss metabolic insults that can underlie the transition from steatosis to steatohepatitis and from steatohepatitis to HCC as well as aberrantly regulated immunometabolic pathways that enable cancer cells to survive and proliferate in the tumor microenvironment. We also discuss therapeutic modalities targeted at HCC prevention and regression. A full understanding of HCC-associated immunometabolic changes in obesity may contribute to clinical treatments that effectively target cancer metabolism.

Cryptogenic hepatocellular carcinoma: characteristics, outcome, and prognostic role of albumin-bilirubin (ALBI) grade vs easy ALBI grade

BACKGROUND

The characteristics and prognosis of cryptogenic hepatocellular carcinoma (HCC) remain unclear. The albumin-bilirubin (ALBI) grade and its updated version, the easy ALBI (EZ-ALBI) grade, are important prognostic predictors for HCC. We aimed to investigate the long-term survival of patients with cryptogenic HCC and the prognostic role of ALBI and EZ-ALBI grade in these patients.

METHODS

A prospective cohort of 2,937 HCC patients with viral or cryptogenic etiology were retrospectively analyzed. The multivariate Cox model was used to determine prognostic predictors.

RESULTS

Cryptogenic HCC patients were often older and diabetic, had lower serum ɑ-fetoprotein (AFP) levels, larger tumor burden, poor performance status, advanced cancer stage, and received non-curative treatments compared with hepatitis B or C-related HCC. The Cox analysis showed that age > 65 years, serum AFP > 400 ng/mL, presence of vascular invasion or distant metastasis, presence of ascites, performance status 2-4, ALBI grade 2 and 3, EZ-ALBI grade 2 and 3, and non-curative treatment, were independent predictors of decreased survival in cryptogenic HCC (p < .001). Significant survival differences were found across ALBI grade and EZ-ALBI grade in cryptogenic HCC and subgroup patients receiving curative or non-curative treatments. The Cancer of Liver Italian Program was the best staging system for patients with cryptogenic HCC.

CONCLUSIONS

Patients with cryptogenic HCC have a larger tumor burden and advanced cancer stage at disease presentation compared with those with viral HCC. The ALBI and EZ-ALBI score are robust models to evaluate liver functional reserve for these patients independent of treatment modality.

Sulfatase 2 Along with Syndecan 1 and Glypican 3 Serum Levels are Associated with a Prognostic Value in Patients with Alcoholic Cirrhosis-Related Advanced Hepatocellular Carcinoma

Purpose

Sulfatase 2 (SULF2) is an enzyme related to heparan sulfate modifications. Its expression, as for some heparan sulfate proteoglycans expression, has been linked to hepatocellular carcinoma (HCC) at mRNA level and immunohistochemistry staining on biopsy samples. This study aims to evaluate the prognostic value of serum levels of SULF2 in patients with alcoholic cirrhosis with or without HCC.

Patients and Methods

Two hundred and eighty-seven patients with alcoholic cirrhosis were enrolled in this study: 164 without HCC, 57 with early HCC, and 66 with advanced HCC at inclusion. We analyzed the association between SULF2 serum levels and prognosis using Kaplan-Meier method and univariate and multivariate analysis using a Cox model.

Results

Child-Pugh C Patients have higher serum levels of SULF2 than Child-Pugh A patients. Serum levels of SULF2 were also higher in patients with advanced HCC compared with the other groups. In patients with advanced HCC, high serum levels of SULF2 were associated with less favorable overall survival. Combination of SULF2 with Glypican 3 (GPC3) and Syndecan 1 (SDC1) serum levels enhanced the ability to discriminate worst prognostic in advanced HCC.

Conclusion

SULF2 along with GPC3 and SDC1 serum levels have been shown to be associated with a prognostic value in advanced HCC.

Metabolomics and Lipidomics Screening Reveal Reprogrammed Signaling Pathways toward Cancer Development in Non-Alcoholic Steatohepatitis

With the rising incidence of hepatocellular carcinoma (HCC) from non-alcoholic steatohepatitis (NASH), identifying new metabolic readouts that function in metabolic pathway perpetuation is still a demand. The study aimed to compare the metabolic signature between NASH and NASH-HCC patients to explore novel reprogrammed metabolic pathways that might modulate cancer progression in NASH patients. NASH and NASH-HCC patients were recruited and screened for metabolomics, and isotope-labeled lipidomics were targeted and profiled using the EXION-LCTM system equipped with a Triple-TOFTM 5600+ system. Results demonstrated significantly (p ≤ 0.05) higher levels of triacylglycerol, AFP, AST, and cancer antigen 19-9 in NASH-HCC than in NASH patients, while prothrombin time, platelet count, and total leukocyte count were decreased significantly (p ≤ 0.05). Serum metabolic profiling showed a panel of twenty metabolites with 10% FDR and p ≤ 0.05 in both targeted and non-targeted analysis that could segregate NASH-HCC from NASH patients. Pathway analysis revealed that the metabolites are implicated in the down-regulation of necroptosis, amino acid metabolism, and regulation of lipid metabolism by PPAR-α, biogenic amine synthesis, fatty acid metabolism, and the mTOR signaling pathway. Cholesterol metabolism, DNA repair, methylation pathway, bile acid, and salts metabolism were significantly upregulated in NASH-HCC compared to the NASH group. Metabolite-protein interactions network analysis clarified a set of well-known protein encoding genes that play crucial roles in cancer, including PEMT, IL4I1, BAAT, TAT, CDKAL1, NNMT, PNP, NOS1, and AHCYL. Taken together, reliable metabolite fingerprints are presented and illustrated in a detailed map for the most predominant reprogrammed metabolic pathways that target HCC development from NASH.

Metabolic Risk Factors for Hepatocellular Carcinoma in Patients with Nonalcoholic Fatty Liver Disease: A Prospective Study

Non-alcoholic fatty liver disease (NAFLD) is a fast-growing public health problem and predisposes to hepatocellular carcinoma (HCC) in a significant proportion of patients. Metabolic alterations might underlie the progression of NAFLD to HCC, but the magnitudes of risk and population-attributable risk fractions (PAFs) for various metabolic conditions that are associated with HCC risk in patients with NAFLD are unknown. We investigated the associations between metabolic conditions and HCC development in individuals with a prior history of NAFLD. The study included 11,245 participants in the SEER-Medicare database, comprising 1310 NAFLD-related HCC cases and 9835 NAFLD controls. We excluded individuals with competing liver diseases (e.g., alcoholic liver disease and chronic viral hepatitis). Baseline pre-existing diabetes mellitus, dyslipidemia, obesity, hypertension, hypothyroidism, and metabolic syndrome were assessed. Multivariable-adjusted logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). PAFs were also calculated for each metabolic condition. The results show that diabetes (OR = 2.39, 95% CI: 2.04-2.79), metabolic syndrome (OR = 1.73, 95% CI: 1.49-2.01), and obesity (OR = 1.62, 95% CI: 1.43-1.85) were associated with a higher HCC risk in individuals with NAFLD. The highest PAF for HCC was observed for pre-existing diabetes (42.1%, 95% CI: 35.7-48.5), followed by metabolic syndrome (28.8%, 95% CI: 21.7-35.9) and obesity (13.2%, 95% CI: 9.6-16.8). The major predisposing factors for HCC in individuals with NAFLD are diabetes mellitus, metabolic syndrome, and obesity, and their control would be critically important in mitigating the rising incidence of NAFLD-related HCC.

RISK FACTORS FOR HEPATOCELLULAR CARCINOMA IN PATIENTS WITH NON-ALCOHOLIC FATTY LIVER DISEASE

Non-alcoholic fatty liver disease is growing in worldwide prevalence and thus, is expected to have a higher number of NAFLD-related hepatocellular carcinoma (HCC) in the following years. This review describes the risk factors associated with HCC in NAFLD-patients. The presence of liver cirrhosis is the preponderant one. Male gender, PNPLA3 variants, diabetes, and obesity also appear to predispose to the development of HCC, even in non-cirrhotic subjects. Thus far, intensive lifestyle modifications, including glycemic control, and obesity treatment, are effective therapies for NAFLD/ non-alcoholic steatohepatitis and, therefore, probably, also for HCC. Some drugs that aimed at decreasing inflammatory activity and fibrosis, as well as obesity, were studied. Other data have suggested the possibility of HCC chemoprevention. So far, however, there is no definitive evidence for the routine utilization of these drugs. We hope, in the future, to be able to profile patients at higher risk of NAFLD-HCC and outline strategies for early diagnosis and prevention.

Overexpression of Hepcidin Alleviates Steatohepatitis and Fibrosis in a Diet-induced Nonalcoholic Steatohepatitis

BACKGROUND AND AIMS

Iron overload can contribute to the progression of nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis (NASH). Hepcidin (Hamp), which is primarily synthesized in hepatocytes, is a key regulator of iron metabolism. However, the role of Hamp in NASH remains unclear. Therefore, we aimed to elucidate the role of Hamp in the pathophysiology of NASH.

METHODS

Male mice were fed a choline-deficient L-amino acid-defined (CDAA) diet for 16 weeks to establish the mouse NASH model. A choline-supplemented amino acid-defined (CSAA) diet was used as the control diet. Recombinant adeno-associated virus genome 2 serotype 8 vector expressing Hamp (rAAV2/8-Hamp) or its negative control (rAAV2/8-NC) was administered intravenously at week 8 of either the CDAA or CSAA diet.

RESULTS

rAAV2/8-Hamp treatment markedly decreased liver weight and improved hepatic steatosis in the CDAA-fed mice, accompanied by changes in lipogenesis-related genes and adiponectin expression. Compared with the control group, rAAV2/8-Hamp therapy attenuated liver damage, with mice exhibiting reduced histological NAFLD inflammation and fibrosis, as well as lower levels of liver enzymes. Moreover, α-smooth muscle actin-positive activated hepatic stellate cells (HSCs) and CD68-postive macrophages increased in number in the CDAA-fed mice, which was reversed by rAAV2/8-Hamp treatment. Consistent with the in vivo findings, overexpression of Hamp increased adiponectin expression in hepatocytes and Hamp treatment inhibited HSC activation.

CONCLUSIONS

Overexpression of Hamp using rAAV2/8-Hamp robustly attenuated liver steatohepatitis, inflammation, and fibrosis in an animal model of NASH, suggesting a potential therapeutic role for Hamp.

Noncoding RNAs in liver physiology and metabolic diseases

The liver holds central roles in detoxification, energy metabolism and whole-body homeostasis but can develop malignant phenotypes when being chronically overwhelmed with fatty acids and glucose. The global rise of metabolic-associated fatty liver disease (MAFLD) is already affecting a quarter of the global population. Pharmaceutical treatment options against different stages of MAFLD do not yet exist and several clinical trials against hepatic transcription factors and other proteins have failed. However, emerging roles of noncoding RNAs, including long (lncRNA) and short noncoding RNAs (sRNA), in various cellular processes pose exciting new avenues for treatment interventions. Actions of noncoding RNAs mostly rely on interactions with proteins, whereby the noncoding RNA fine-tunes protein function in a process termed riboregulation. The developmental stage-, disease stage- and cell type-specific nature of noncoding RNAs harbors enormous potential to precisely target certain cellular pathways in a spatio-temporally defined manner. Proteins interacting with RNAs can be categorized into canonical or non-canonical RNA binding proteins (RBPs) depending on the existence of classical RNA binding domains. Both, RNA- and RBP-centric methods have generated new knowledge of the RNA-RBP interface and added an additional regulatory layer. In this review, we summarize recent advances of how of RBP-lncRNA interactions and various sRNAs shape cellular physiology and the development of liver diseases such as MAFLD and hepatocellular carcinoma.

Discovering Biomarkers for Non-Alcoholic Steatohepatitis Patients with and without Hepatocellular Carcinoma Using Fecal Metaproteomics

High-calorie diets lead to hepatic steatosis and to the development of non-alcoholic fatty liver disease (NAFLD), which can evolve over many years into the inflammatory form of non-alcoholic steatohepatitis (NASH), posing a risk for the development of hepatocellular carcinoma (HCC). Due to diet and liver alteration, the axis between liver and gut is disturbed, resulting in gut microbiome alterations. Consequently, detecting these gut microbiome alterations represents a promising strategy for early NASH and HCC detection. We analyzed medical parameters and the fecal metaproteome of 19 healthy controls, 32 NASH patients, and 29 HCC patients, targeting the discovery of diagnostic biomarkers. Here, NASH and HCC resulted in increased inflammation status and shifts within the composition of the gut microbiome. An increased abundance of kielin/chordin, E3 ubiquitin ligase, and nucleophosmin 1 represented valuable fecal biomarkers, indicating disease-related changes in the liver. Although a single biomarker failed to separate NASH and HCC, machine learning-based classification algorithms provided an 86% accuracy in distinguishing between controls, NASH, and HCC. Fecal metaproteomics enables early detection of NASH and HCC by providing single biomarkers and machine learning-based metaprotein panels.

Modulation of hepatic stellate cells by Mutaflor® probiotic in non-alcoholic fatty liver disease management

BACKGROUND

NAFLD and NASH are emerging as primary causes of chronic liver disease, indicating a need for an effective treatment. Mutaflor® probiotic, a microbial treatment of interest, was effective in sustaining remission in ulcerative colitis patients.

OBJECTIVE

To construct a genetic-epigenetic network linked to HSC signaling as a modulator of NAFLD/NASH pathogenesis, then assess the effects of Mutaflor® on this network.

METHODS

First, in silico analysis was used to construct a genetic-epigenetic network linked to HSC signaling. Second, an investigation using rats, including HFHSD induced NASH and Mutaflor® treated animals, was designed. Experimental procedures included biochemical and histopathologic analysis of rat blood and liver samples. At the molecular level, the expression of genetic (FOXA2, TEAD2, and LATS2 mRNAs) and epigenetic (miR-650, RPARP AS-1 LncRNA) network was measured by real-time PCR. PCR results were validated with immunohistochemistry (α-SMA and LATS2). Target effector proteins, IL-6 and TGF-β, were estimated by ELISA.

RESULTS

Mutaflor® administration minimized biochemical and histopathologic alterations caused by NAFLD/NASH. HSC activation and expression of profibrogenic IL-6 and TGF-β effector proteins were reduced via inhibition of hedgehog and hippo pathways. Pathways may have been inhibited through upregulation of RPARP AS-1 LncRNA which in turn downregulated the expression of miR-650, FOXA2 mRNA and TEAD2 mRNA and upregulated LATS2 mRNA expression.

CONCLUSION

Mutaflor® may slow the progression of NAFLD/NASH by modulating a genetic-epigenetic network linked to HSC signaling. The probiotic may be a useful modality for the prevention and treatment of NAFLD/NASH.

Are isothiocyanates and polyphenols from Brassicaceae vegetables emerging as preventive/therapeutic strategies for NAFLD? The landscape of recent preclinical findings

Nonalcoholic fatty liver disease (NAFLD) is a lipid impairment-related chronic metabolic disease that affects almost 25% of the worldwide population and has become the leading cause of liver transplantation in the United States of America (USA). NAFLD may progress from simple hepatic steatosis (HS) to nonalcoholic steatohepatitis (NASH), which occurs simultaneously in an inflammatory and fibrotic microenvironment and affects approximately 5% of the global population. Recently, NASH has been suggested to be a relevant driver in progressive liver cirrhosis and a population-attributable factor in hepatocellular carcinoma patients. Moreover, predictions show that NAFLD-related annual health costs in the USA have reached ∼$100 bi., but effective therapies are still scarce. Thus, new preventative strategies for this hepatic disease urgently need to be developed. The Brassicaceae vegetable family includes almost 350 genera and 3500 species and these are one of the main types of vegetables harvested and produced worldwide. These vegetables are well-known sources of glucobrassicin-derivative molecules, such as isothiocyanates and phenolic compounds, which have shown antioxidant and antilipogenic effects in preclinical NAFLD data. In this review, we gathered prominent evidence of the in vivo and in vitro effects of these vegetable-derived nutraceutical compounds on the gut-liver-adipose axis, which is a well-known regulator of NAFLD and may represent a new strategy for disease control.

Multiple Mechanisms of Shenqi Pill in Treating Nonalcoholic Fatty Liver Disease Based on Network Pharmacology and Molecular Docking

Background

Shenqi pill (SQP), a traditional Chinese prescription, has proven to be effective in treating nonalcoholic fatty liver disease (NAFLD). However, its bioactive ingredients and underlying mechanisms remain elusive.

Aim

We aimed to predict the active compounds, potential targets, and molecular mechanisms of SQP anti-NAFLD by applying network pharmacology and molecular docking methods.

Methods

Active ingredients and related targets of SQP were obtained from the TCMSP database. Potential targets of NAFLD were acquired from OMIM and GeneCards databases. The STRING database and Cytoscape software analyzed the protein-protein interaction (PPI) network and core targets of overlapping genes between SQP and NAFLD. GO enrichment analysis and KEGG enrichment analysis were performed in the DAVID database. Finally, molecular docking was employed to find possible binding conformations of macromolecular targets.

Results

15 anti-NAFLD bioactive ingredients and 99 anti-NAFLD potential targets of SQP were determined using Network pharmacology. Quercetin, kaempferol, stigmasterol, diosgenin, and tetrahydroalstonine were the major active ingredients and AKT1, TNF, MAPK8, IL-6, and VEGFA were the key target proteins against NAFLD. The KEGG analysis suggested that the main pathways included PI3K/Akt signaling pathway, HIF-1 signaling pathway, MAPK signaling pathway, and TNF signaling pathway. Molecular docking predicted that quercetin, kaempferol, stigmasterol, diosgenin, and tetrahydroalstonine could bind with AKT1, TNF, and MAPK8.

Conclusion

This study successfully predicts the active compounds, potential targets, and signaling pathways of SQP against NAFLD. Moreover, this study contributed to the application and development of SQP.

Melatonin Suppresses NLRP3 Inflammasome Activation via TLR4/NF-κB and P2X7R Signaling in High-Fat Diet-Induced Murine NASH Model

Background

NLRP3 inflammasome activation plays a critical role in mediating inflammation and NASH (non-alcoholic steatohepatitis) progression that ultimately leads to cirrhosis and hepatocellular carcinoma. Melatonin (MLT) controls high-fat diet-induced NASH in the murine model by modulating NLRP3 mediated inflammation. P2X7R-mediated inflammasome activation is reported in several inflammatory models including NASH.

Objective

The role of MLT in P2X7R-mediated inflammation in the NASH model has not yet been explored. The present study investigated the role of MLT in amending high-fat diet-induced nonalcoholic steatohepatitis in the murine liver.

Methods

To evaluate the hepatological changes, mice were divided into four groups to investigate the improvement potential of this MLT (10 and 20 mg/kg) and to assess the experimental findings. Histology, biochemical assays, ELISA, FACS analysis, Western blotting, and IF were performed to assess the physical and molecular changes upon melatonin treatment.

Results

The result demonstrated that MLT administration reduced HFD (high-fat diet)-induced non-alcoholic steatohepatitic indices, which successively restored the hepatic morphological architecture and other pathophysiological features too. Moreover, the application of MLT suppressed HFD-induced activation of the inflammasome and through TLR4/NF-κB signaling. Herein, we report that MLT significantly suppresses P2X7R expression and calcium influx along with inflammasome in both in vitro and in vivo. The docking study revealed a strong binding affinity of MLT with P2X7R. Moreover, the results also showed that the Nrf2 level was boosted which may normalize the expression of antioxidant proteins that safeguard against oxidative damage triggered by inflammation. Furthermore, some matrix metalloproteinases like MMP 2 and MMP 9 were repressed and TIMP-1 level was increased, which also signifies that MLT could improve liver fibrosis in this model.

Conclusion

Based on our findings, this study may conclude that MLT could be used as a therapeutic agent in the high-fat diet-induced NASH model as it has persuasive anti-inflammatory potential.

Prognostic and Predictive Factors in Patients with Advanced HCC and Elevated Alpha-Fetoprotein Treated with Ramucirumab in Two Randomized Phase III Trials

PURPOSE

Ramucirumab is an effective treatment for patients with advanced hepatocellular carcinoma (aHCC) and baseline alpha-fetoprotein (AFP) ≥400 ng/mL. We aimed to identify prognostic and predictive factors of response to ramucirumab in patients with aHCC with AFP ≥400 ng/mL from the phase III REACH and REACH-2 randomized trials.

PATIENTS AND METHODS

Patients with aHCC, Child-Pugh class A with prior sorafenib treatment were randomized in REACH and REACH-2 (ramucirumab 8 mg/kg or placebo, biweekly). Meta-analysis of individual patient-level data (pooled population) from REACH (AFP ≥400 ng/mL) and REACH-2 was performed. A drug exposure analysis was conducted for those with evaluable pharmacokinetic data. To identify potential prognostic factors for overall survival (OS), multivariate analyses were performed using a Cox proportional hazards regression model. To define predictors of ramucirumab benefit, subgroup-by-treatment interaction terms were evaluated.

RESULTS

Of 542 patients (316 ramucirumab, 226 placebo) analyzed, eight variables had independent prognostic value associated with poor outcome (geographical region, Eastern Cooperative Oncology Group performance score ≥1, AFP >1,000 ng/mL, Child-Pugh >A5, extrahepatic spread, high neutrophil-to-lymphocyte ratio, high alkaline phosphatase and aspartate aminotransferase). Ramucirumab survival benefit was present across all subgroups, including patients with very aggressive HCC [above median AFP; HR: 0.64; 95% confidence interval (CI): 0.49-0.84] and nonviral aHCC (HR: 0.56; 95% CI: 0.40-0.79). While no baseline factor was predictive of a differential OS benefit with ramucirumab, analyses demonstrated an association between high drug exposure, treatment-emergent hypertension (grade ≥3), and increased ramucirumab benefit.

CONCLUSIONS

Ramucirumab provided a survival benefit irrespective of baseline prognostic covariates, and this benefit was greatest in patients with high ramucirumab drug exposure and/or those with treatment-related hypertension.

Non-alcoholic fatty liver disease development: A multifactorial pathogenic phenomena

Non-alcoholic fatty liver disease (NAFLD), characterized by the accumulation of excessive intrahepatic fat, is a leading metabolic disorder also considered as the hepatic manifestation of metabolic syndrome (MS). Though more commonly observed in obese individuals and those with metabolic risk factors, it also develops in a considerable number of non-obese individuals as well as participants without having any component of MS. The basic mechanism involved in the development of fatty liver is the imbalance between lipid uptake, synthesis, and metabolism in the liver, normally controlled by several mechanisms to maintain lipid homeostasis. As a complex progressive liver disorder, the NAFLD pathogenesis is multifactorial, and several new pathogenic phenomena were discovered over time. The available literature suggests the role of both genetic and environmental factors and associated metabolic factors; however, the mechanism of progression is not completely understood. In this review, we discuss different pathogenic mechanisms and their interplay to provide an elaborate idea regarding NAFLD development and progression. Better understanding of pathogenic mechanisms will be useful in finding new treatment for patients with NAFLD.

The Importance of Metabolic Syndrome Status for the Risk of Non-Viral Hepatocellular Carcinoma: A Nationwide Population-Based Study

The positive association between metabolic syndrome (MetS) and hepatocellular carcinoma (HCC) has been suggested. However, no studies have yet looked at how the risk of developing HCC varies with changes in MetS status. Therefore, we aimed to investigate the association between changes in MetS and subsequent HCC development. Data were obtained from the Korean National Health Insurance Service. In this study, 5,975,308 individuals who participated in health screenings both in 2009-2010 and 2011-2012 were included. Individuals with preexisting viral hepatitis, liver cirrhosis, or cancer diagnoses were excluded. Subjects were divided into four groups according to change in MetS status during the 2-year interval screening (from 2009 to 2011): sustained non-MetS, transition to MetS, transition to non-MetS, and sustained MetS. Cox regression analysis was used to examine the hazard ratios of HCC. The subjects were followed through December 31, 2018. During a median of 7.3 years of follow-up, 25,880 incident HCCs were identified. Compared to the sustained non-MetS group, age, sex, smoking, alcohol, regular exercise, and body mass index-adjusted hazard ratios (95% confidence interval) for HCC development were 1.01 (0.97-1.05) for the transition to MetS group, 1.05 (1.003-1.09) for the transition to non-MetS group, and 1.07 (1.03-1.10) for the sustained MetS group. Stratified analyses according to age, sex, smoking, alcohol intake, exercise, diabetes mellitus, hypertension, dyslipidemia, and chronic kidney disease showed similar results. A significantly increased HCC risk was observed in the sustained MetS and transition to non-MetS groups. The baseline status of MetS was associated with the risk of HCC development. Strategies to improve MetS, especially targeting insulin resistance, might prevent HCC development.

Prevalence of Non-alcoholic Fatty Liver Disease in India: A Systematic Review and Meta-analysis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) contributes to a large proportion of liver disease burden in the world. Several groups have studied the prevalence of NAFLD in the Indian population.

AIM

A systematic review of the published literature and meta-analysis was carried out to estimate the prevalence of NAFLD in the Indian population.

METHODS

English language literature published until April 2021 was searched from electronic databases. Original data published in any form which had reported NAFLD prevalence in the Indian population were included. The subgroup analysis of prevalence was done based on the age (adults or children) and risk category, i.e., average-risk group (community population, participants of control arm, unselected participants, hypothyroidic individuals, athletes, aviation crew, and army personnel) and high-risk group (obesity or overweight, diabetes mellitus, coronary artery disease, etc.). The prevalence estimates were pooled using the random-effects model. Heterogeneity was assessed with I2.

RESULTS

Sixty-two datasets (children 8 and adults 54) from 50 studies were included. The pooled prevalence of NAFLD was estimated from 2903 children and 23,581 adult participants. Among adults, the estimated pooled prevalence was 38.6% (95% CI 32-45.5). The NAFLD prevalence in average-risk and high-risk subgroups was estimated to be 28.1% (95% CI 20.8-36) and 52.8% (95% CI 46.5-59.1), respectively. The estimated NAFLD prevalence was higher in hospital-based data (40.8% [95% CI 32.6-49.3%]) than community-based data (28.2% [95% CI 16.9-41%]). Among children, the estimated pooled prevalence was 35.4% (95% CI 18.2-54.7). The prevalence among non-obese and obese children was 12.4 (95% CI 4.4-23.5) and 63.4 (95% CI 59.4-67.3), respectively.

CONCLUSION

Available data suggest that approximately one in three adults or children have NAFLD in India.

Naltrexone protects against BDL-induced cirrhosis in Wistar rats by attenuating thrombospondin-1 and enhancing antioxidant defense system via Nrf-2

AIMS

It is well-established that thrombospondin-1 (THBS-1), vascular endothelial growth factor-A (VEGF-A), nuclear factor-erythroid 2-related factor 2 (Nrf-2), Kelch-like ECH-associated protein 1 (Keap-1), and transforming growth factor-beta 1 (TGF-β1) are the pivotal players of liver fibrosis. Recent studies have shown that endogenous opioid levels increase during liver cirrhosis. Therefore, the present study aimed to clarify the effect of naltrexone (NTX), an opioid antagonist, on the alteration of these factors following bile duct ligation (BDL)-induced liver cirrhosis.

MAIN METHODS

Wistar male rats (n = 50) were categorized equally into 5 groups (baseline, sham+saline, BDL + saline, sham+NTX (10 mg/kg of body weight (BW)), and BDL + NTX (10 mg/kg of BW)). At the end of the experiment, H&E staining was used to assess necrosis and lobular damage of hepatic tissue. The gene expression of THBS-1 and NADPH oxidase 1 (NOX-1) was measured by real time-PCR and VEGF-A, Nrf-2, Keap-1, and TGF-β1 protein levels were assessed by western blot. The antioxidant enzymes activity, total oxidant status (TOS) and MDA level were measured by commercial kits.

KEY FINDINGS

Hepatic necrosis and lobular damage increased substantially and NTX reduced them markedly in the BDL group. Gene expression of hepatic THBS-1 and NOX-1, TOS and MDA levels increased markedly in the BDL + saline group, and Nrf-2 and VEGF-A values decreased significantly in the BDL + NTX group. NTX recovered THBS-1, NOX-1 and Nrf-2 in the BDL + NTX group, substantially (p-value ≤ 0.05).

SIGNIFICANCE

Data showed that NTX treatment attenuates liver fibrosis mainly by lowering THBS-1 and NOX-1 and increasing Nrf-2 protein level and antioxidant enzymes.

Encouraging specific biomarkers-based therapeutic strategies for hepatocellular carcinoma

The prevention, early discovery and effective treatment of patients with hepatocellular carcinoma (HCC) remain a global medical challenge. At present, HCC is still mainly treated by surgery, supplemented by vascular embolization, radio frequency, radiotherapy, chemotherapy and biotherapy. The application of multikinase inhibitor sorafenib, chimeric antigen receptor T cells, or PD-1/PD-L1 inhibitors can prolong the median survival of HCC patients. However, the treatment efficacy is still unsatisfactory due to HCC metastasis and postoperative recurrence. During the process of hepatocyte malignant transformation, HCC tissues can express and secrete many types of specific biomarkers, or oncogenic antigen molecules into blood, for example, alpha-fetoprotein, glypican-3, Wnt3a (one of the key signaling molecules in the Wnt/β-catenin pathway), insulin-like growth factor (IGF)-II or IGF-I receptor, vascular endothelial growth factor, secretory clusterin and so on. In addition, combining immunotherapy with non-coding RNAs might improve anti-cancer efficacy. These biomarkers not only contribute to HCC diagnosis or prognosis, but may also become molecular targets for HCC therapy under developing or clinical trials. This article reviews the progress in emerging biomarkers in basic research or clinical trials for HCC immunotherapy.

Targeting Wnt/β-Catenin Pathways in Primary Liver Tumours: From Microenvironment Signaling to Therapeutic Agents

Primary liver cancers (PLCs) are steadily increasing in incidence and mortality in the world. They have a poor prognosis due to their silent nature, late discovery and resistance to common chemotherapy. At present, there are limited treatment alternatives, and the understanding of PLC molecular aspects is essential to develop more efficient drugs and therapeutic surgical and loco-regional strategies. A clear causal link with liver damage, inflammation, and regeneration has been found in the occurrence of PLC over the last few decades. Physiologically, Wingless/It (Wnt)-β-catenin signaling plays a key role in liver development, metabolic zonation and regeneration. Loss of functional homeostasis of this pathway appears to be a major driver of carcinogenesis in the liver parenchyma. In the hepatic microenvironment, molecular deregulations that exceed the Wnt signaling biological capacity can induce tumor initiation and progression. Indeed, somatic mutations are identified in key components of canonical and non-canonical Wnt signaling and in PLCs and precancerous lesions. In this review, the altered functions of Wnt/β-catenin signaling are considered in human PLCs, with emphasis on hepatocellular carcinomas (HCC), cholangiocarcinomas (CCA) and hepatoblastomas (HB). Based on recent literature, we also focused on liver cancerogenesis through Wnt deregulation. An overview of preclinical and clinical studies on approved and experimental drugs, targeting the Wnt/β-catenin cascade in PLCs, is proposed. In addition, the clinical implication of molecule inhibitors that have been shown to possess activity against the Wnt pathway in association with conventional surgical and loco-regional therapies are reviewed.

Elevated Serum Regulator of Calcineurin 2 is Associated With an Increased Risk of Non-Alcoholic Fatty Liver Disease

Background: The promoting effect of the regulator of calcineurin 2 (RCAN2) in hepatic steatosis has been observed in animal studies. However, the association of RCAN2 with non-alcoholic fatty liver disease (NAFLD) in humans remains unclear. This study aimed to evaluate the expression of RCAN2 in the liver of mice with hepatic steatosis and in the serum of NAFLD patients and to explore the relationship between serum RCAN2 levels and NAFLD.

Methods: The mRNA and protein expression of RCAN2 were detected by quantitative real-time PCR (qRT-PCR) and Western blot. NAFLD was diagnosed by abdominal ultrasonography. Circulating RCAN2 levels were measured by ELISA kits. The relationship between serum RCAN2 levels and NAFLD was assessed.

Results: qRT-PCR and Western blot analysis showed that compared with the corresponding controls, the mRNA and protein expression of RCAN2 were significantly increased in the liver tissues of db/db and mice on a high-fat diet. Serum RCAN2 levels were markedly elevated in NAFLD patients compared with non-NAFLD subjects. Binary logistic regression analysis showed that serum RCAN2 levels were significantly associated with NAFLD. Receiver operation characteristic (ROC) curve analysis showed that serum RCAN2 might act as a predictive biomarker for NAFLD [area under the curve (AUC) = 0.663, 95% CI = 0.623–0.702], and the serum RCAN2/(AST/ALT) ratio displayed improved predictive accuracy (AUC = 0.816, 95% CI = 0.785–0.846).

Conclusion: Elevated serum RCAN2 levels were associated with an increased risk of NAFLD. Serum RCAN2, especially the serum RCAN2/(AST/ALT) ratio, might be a candidate diagnostic marker for NAFLD.

Hepatoprotective effects of gemigliptin and empagliflozin in a murine model of diet-induced non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) includes a broad spectrum of liver diseases characterized by steatosis, inflammation, and fibrosis. This study aimed to investigate the potential of dipeptidyl peptidase-4 inhibitors and sodium-glucose cotransporter 2 inhibitors in alleviating the progression of NAFLD. The NAFLD model was generated by feeding male C57BL/6J mice a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) for 7 weeks. After 2 weeks of CDAHFD feeding, the NAFLD model mice were assigned to four groups, namely (ⅰ) VEHICLE, (ⅱ) gemigliptin (GEMI), (ⅲ) empagliflozin (EMPA), and (ⅳ) GEMI + EMPA. For the next 5 weeks, mice received the vehicle or the drug based upon the group to which they belonged. Thereafter, the triglyceride concentration, extent of fibrosis, and the expression of genes encoding inflammatory cytokines, chemokines, and antioxidant enzymes were analyzed in the livers of mice. The NAFLD activity score and hepatic fibrosis grade were assessed via hematoxylin and eosin and Sirius Red staining of the liver tissue samples. All mice belonging to the GEMI, EMPA, and GEMI + EMPA groups showed improvements in the accumulation of liver triglycerides and the expression of inflammatory cytokines and chemokines. Additionally, the oxidative stress was reduced due to inhibition of the c-Jun N-terminal kinase pathway and upregulation of the antioxidant enzymes. Furthermore, in these three groups, the galectin-3 and interleukin 33-induced activity of tumor necrosis factor-α was inhibited, thereby preventing the progression of liver fibrosis. These findings suggest that the GEMI, EMPA, and GEMI + EMPA treatments ameliorate hepatic steatosis, inflammation, oxidative stress, and fibrosis in CDAHFD-induced NAFLD mouse models.

Does moderate alcohol consumption accelerate the progression of liver disease in NAFLD? A systematic review and narrative synthesis

OBJECTIVES

Liver disease is a leading cause of premature death, partly driven by the increasing incidence of non-alcohol-related fatty liver disease (NAFLD). Many people with a diagnosis of NAFLD drink moderate amounts of alcohol. There is limited guidance for clinicians looking to advise these patients on the effect this will have on their liver disease progression. This review synthesises the evidence on moderate alcohol consumption and its potential to predict liver disease progression in people with diagnosed NAFLD.

METHODS

A systematic review of longitudinal observational cohort studies was conducted. Databases (Medline, Embase, The Cochrane Library and ClinicalTrials.gov) were searched up to September 2020. Studies were included that reported progression of liver disease in adults with NAFLD, looking at moderate levels of alcohol consumption as the exposure of interest. Risk of bias was assessed using the Quality in Prognostic factor Studies tool.

RESULTS

Of 4578 unique citations, 6 met the inclusion criteria. Pooling of data was not possible due to heterogeneity and studies were analysed using narrative synthesis. Evidence suggested that any level of alcohol consumption is associated with worsening of liver outcomes in NAFLD, even for drinking within recommended limits. Well conducted population based studies estimated up to a doubling of incident liver disease outcomes in patients with NAFLD drinking at moderate levels.

CONCLUSIONS

This review found that any level of alcohol intake in NAFLD may be harmful to liver health.Study heterogeneity in definitions of alcohol exposure as well as in outcomes limited quantitative pooling of results. Use of standardised definitions for exposure and outcomes would support future meta-analysis.Based on this synthesis of the most up to date longitudinal evidence, clinicians seeing patients with NAFLD should currently advise abstinence from alcohol.

PROSPERO REGISTRATION NUMBER

The protocol was registered with PROSPERO (#CRD42020168022).

Models of nonalcoholic steatohepatitis potentiated by chemical inducers leading to hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most common primary liver cancer, arises after a long period of exposure to etiological factors. Nonalcoholic steatohepatitis (NASH) is ranked as the main risk factor for developing HCC; hence, experimental models of NASH leading to HCC have become key tools both to investigate the molecular mechanisms underlying the pathophysiology and to evaluate new putative drugs for treating chronic liver diseases in humans. Animal models of NASH induced by a high-fat diet (HFD) plus chemical inducers, such as the NASH-HCC (STAM), high-fat diet/diethylnitrosamine (HFD/DEN), choline-deficient high-fat diet/DEN (CDHFD/DEN), and Western diet/carbon tetrachloride (WD/CCl₄) models, are promising because they exacerbate liver damage and significantly shorten the experimental time. In this review, we critically summarize and discuss the ability of these models to recapitulate the liver alterations that precede and lead to HCC progression, as well as the impact of the diet in promoting liver injury progression. We also emphasize the strengths and weaknesses of the models' ability to closely mimic the stages of liver injury development that occur in humans. Based on the molecular mechanisms induced by the currently available NASH models leading to HCC, we argue that although several NASH models have importantly contributed to describing the disease chronology, the progress in emulating the progression from NASH to HCC has been partial. Thus, the development of novel NASH/HCC models remains an unmet need.

Metabolically healthy and unhealthy obesity and the progression of liver fibrosis: A cross-sectional study

BACKGROUND

The development of liver fibrosis is the most important predictor of adverse outcomes in patients with non-alcoholic fatty liver disease (NAFLD). Little is known regarding the risk factors for the progression of NAFLD to liver fibrosis. The present cross-sectional study aimed to examine the association of liver fibrosis with metabolically healthy and unhealthy obesity among patients with NAFLD.

METHODS

The severity of fatty liver was examined using ultrasonography. We used the NAFLD fibrosis score to determine the severity of liver fibrosis. Anthropometric indices, physical activity, and body composition were assessed. Blood samples were collected to determine serum metabolic parameters. Participants without any component of metabolic syndrome and homeostasis model assessment of insulin resistance (HOMA-IR) <2.5 were considered as metabolically healthy. To examine the association of liver fibrosis with metabolically healthy and unhealthy obesity, multivariable-adjusted odds ratios (ORs) were applied.

RESULTS

The current study included a total of 246 patients with NAFLD and low probability of fibrosis. 46.3% of subjects were metabolically healthy and 53.7% were metabolically unhealthy. Among metabolically healthy subjects, multivariable-adjusted ORs (CIs) for worsening of NAFLD fibrosis score comparing body mass indexes (BMIs) 23.0-24.9, 25-29.9, and ≥30 with a BMI=18.5-22.9 kg/m² were 1.28 (1.09-1.56), 1.99 (1.49-2.63), and 3.96 (2.89-4.71), respectively. The corresponding ORs (95% CIs) among metabolically unhealthy subjects were 1.39 (1.32-1.64), 2.27 (1.98-2.49), and 4.11 (3.12-4.93), respectively. Moreover, in both healthy and unhealthy individuals, higher percentages of body fat and waist circumference were significantly associated with worsening of NAFLD fibrosis score.

CONCLUSION

Excess body fat contributes to the progression of liver fibrosis regardless of metabolic health status.

Hepatic sexual dimorphism - implications for non-alcoholic fatty liver disease

The liver is often thought of as a single functional unit, but both its structural and functional architecture make it highly multivalent and adaptable. In any given physiological situation, the liver can maintain metabolic homeostasis, conduct appropriate inflammatory responses, carry out endobiotic and xenobiotic transformation and synthesis reactions, as well as store and release multiple bioactive molecules. Moreover, the liver is a very resilient organ. This resilience means that chronic liver diseases can go unnoticed for decades, yet culminate in life-threatening clinical complications once the adaptive capacity of the liver is overwhelmed. Non-alcoholic fatty liver disease (NAFLD) predisposes individuals to cirrhosis and increases liver-related and cardiovascular disease-related mortality. This Review discusses the accumulating evidence of sexual dimorphism in NAFLD, which is currently rarely considered in preclinical and clinical studies. Increased awareness of the mechanistic causes of hepatic sexual dimorphism could lead to improved understanding of the biological processes that are dysregulated in NAFLD, to the identification of relevant therapeutic targets and to improved risk stratification of patients with NAFLD undergoing therapeutic intervention.

Microbiome, fibrosis and tumor networks in a non-alcoholic steatohepatitis model of a choline-deficient high-fat diet using diethylnitrosamine

BACKGROUND & AIMS

Hepatocellular carcinoma in nonalcoholic steatohepatitis is caused by the complex factors of inflammation, fibrosis and microbiomes. We used network analysis to examine the interrelationships of these factors.

METHODS

C57Bl/6 mice were categorized into groups: choline-sufficient high-fat (CSHF, n = 8), choline-deficient high-fat (CDHF, n = 9), and CDHF+ diethylnitrosamine (DEN, n = 8). All mice were fed CSHF or CDHF for 20 weeks starting at week 8, and mice in the CDHF + DEN group received one injection of DEN at 3 weeks of age. Bacterial gene was isolated from feces and analyzed using Miseq.

RESULTS

The CSHF group had less fibrosis than the other groups. Tumors were found in 22.2% and 87.5% of the CDHF group and CDHF + DEN groups, respectively. Gene expression in the liver of Cdkn1a (p21: tumor-suppressor) and c-jun was highest in the CDHF group. Bacteroides, Roseburia, Odoribacter, and Clostridium correlated with fibrosis. Streptococcus and Dorea correlated with inflammation and tumors. Akkermansia and Bilophila were inversely correlated with fibrosis and Bifidobacterium was inversely correlated with tumors.

CONCLUSIONS

DEN suppressed the overexpression of p21 caused by CDHF. Some bacteria formed a relationship networking associated with their progression and inhibition for tumors and fibrosis.