Fibrosis and alcohol-related liver disease

The current landscape of antifibrotic therapy across different organs: A systematic approach

Fibrosis is a common pathological process that can affect virtually all the organs, but there are hardly any effective therapeutic options. This has led to an intense search for antifibrotic therapies over the last decades, with a great number of clinical assays currently underway. We have systematically reviewed all current and recently finished clinical trials involved in the development of new antifibrotic drugs, and the preclinical studies analyzing the relevance of each of these pharmacological strategies in fibrotic processes affecting tissues beyond those being clinically studied. We analyze and discuss this information with the aim of determining the most promising options and the feasibility of extending their therapeutic value as antifibrotic agents to other fibrotic conditions.

Metabolic phenotyping of patients with Advanced Chronic Liver Disease for better characterization of Cirrhosis Regression

BACKGROUND & AIMS

Regression of cirrhosis has been observed in patients with viral and non-viral etiologies of liver disease in whom the underlying cause of liver injury was effectively suppressed. However, the understanding of the factors contributing to reversibility of fibrosis and cirrhosis is limited. Our aims were to assess clinical factors, perform genotyping of known variants, and comprehensive metabolic phenotyping to characterize the regression of fibrosis in patients with compensated advanced chronic liver disease (cACLD).

METHODS

In a case-control pilot study with 81 cACLD patients, we compared individuals exhibiting histological or clinical evidence of cACLD regression ("regressors"; n=44) with those showing no improvement ("non-regressors"; n=37) after a minimum of 24 months of successful therapy of the cause of liver disease. Data were validated using an external validation cohort (n=30).

RESULTS

Regardless of the cause of cACLD, the presence of obesity (OR 0.267 95%CI:0.072-0.882; P=0.049), high liver stiffness (OR 0.960, 95%CI:0.925-0.995; P=0.032), and carriage of GCKR variant rs1260326 (OR 0.148, 95%CI:0.030-0.773; P=0.019) are associated with a reduced likelihood of fibrosis regression in a subgroup of 60 ACLD patients genotyped for known genetic variants. Using liver tissue transcriptomics, we identified metabolic pathways differentiating regressors from non-regressors, with top pathways associated to lipid metabolism -especially fatty acids, bile acids, phospholipids, triacylglycerides (biosynthesis), and the carnitine shuttle. In the entire discovery cohort, we further measured metabolites within the defined pathways, which led to identifying 33 circulating markers differentiating regressors from non-regressors after etiological therapy. The validation cohort confirmed 14 of the differentially expressed markers.

CONCLUSIONS

We identified and validated a group of lipid biomarkers associated with regression of fibrosis that could be used as non-invasive biomarker for detecting regression of fibrosis in cACLD.

Effectiveness of 1-year pemafibrate treatment on steatotic liver disease: the influence of alcohol consumption

BACKGROUND/AIMS

Pemafibrate is a selective peroxisome proliferator-activated receptor α modulator that improves serum alanine aminotransferase (ALT) in dyslipidemia patients. We previously reported that pemafibrate significantly improves liver function, serum triglyceride (TG) levels and liver stiffness in non-alcoholic fatty liver disease patients, however the influence of alcohol consumption was not considered. Therefore, we explored pemafibrate efficacy in patients with steatotic liver disease (SLD) and alcohol-associated liver disease (ALD).

METHODS

We retrospectively evaluated pemafibrate efficacy on liver enzymes and lipids in metabolic dysfunction-associated SLD (MASLD) (n = 93), MASLD plus increased alcohol intake (MetALD; n = 23) and ALD (n = 22) patients who had taken pemafibrate for at least 48 weeks. Liver shear wave velocity (SWV, n = 75) was also evaluated.

RESULTS

In MASLD group, ALT, aspartate aminotransferase (AST), γ-glutamyl transpeptidase (γ-GTP) and TG values were significantly decreased from baseline to week 24 and week 48 ( P  < 0.0001). ALT and TG values in MetALD group and ALT and AST values in ALD group were also significantly decreased from baseline to week 24 and week 48. Study participant SWV values decreased from baseline to week 48. We observed no significant difference in changes to ALT, AST, γ-GTP and TG (value at week 24 or week 48 minus value at baseline) among the three groups.

CONCLUSION

Pemafibrate improves liver function and liver stiffness thus making it a promising therapeutic agent for SLD, even in patients with excess alcohol consumption (MetALD and ALD groups).

Mechanism of PANoptosis in metabolic dysfunction-associated steatotic liver disease

In recent years, the incidence of metabolic dysfunction-associated steatotic liver disease (MASLD) has been steadily rising, emerging as a major chronic liver disease of global concern. The course of MASLD is varied, spanning from MASLD to metabolic dysfunction associated steatohepatitis (MASH). MASH is an important contributor to cirrhosis, which may subsequently lead to hepatocellular carcinoma. It has been found that PANoptosis, an emerging inflammatory programmed cell death (PCD), is involved in the pathogenesis of MASLD and facilitates the development of NASH, eventually resulting in inflammatory fibrosis and hepatocyte death. This paper reviews the latest research progress on PANoptosis and MASLD to understand the mechanism of MASLD and provide new directions for future treatment and drug development.

Tumor necrosis factor-inducible gene 6 protein and its derived peptide ameliorate liver fibrosis by repressing CD44 activation in mice with alcohol-related liver disease

BACKGROUND

Alcohol-related liver disease (ALD) is a major health concern worldwide, but effective therapeutics for ALD are still lacking. Tumor necrosis factor-inducible gene 6 protein (TSG-6), a cytokine released from mesenchymal stem cells, was shown to reduce liver fibrosis and promote successful liver repair in mice with chronically damaged livers. However, the effect of TSG-6 and the mechanism underlying its activity in ALD remain poorly understood.

METHODS

To investigate its function in ALD mice with fibrosis, male mice chronically fed an ethanol (EtOH)-containing diet for 9 weeks were treated with TSG-6 (EtOH + TSG-6) or PBS (EtOH + Veh) for an additional 3 weeks.

RESULTS

Severe hepatic injury in EtOH-treated mice was markedly decreased in TSG-6-treated mice fed EtOH. The EtOH + TSG-6 group had less fibrosis than the EtOH + Veh group. Activation of cluster of differentiation 44 (CD44) was reported to promote HSC activation. CD44 and nuclear CD44 intracellular domain (ICD), a CD44 activator which were upregulated in activated HSCs and ALD mice were significantly downregulated in TSG-6-exposed mice fed EtOH. TSG-6 interacted directly with the catalytic site of MMP14, a proteolytic enzyme that cleaves CD44, inhibited CD44 cleavage to CD44ICD, and reduced HSC activation and liver fibrosis in ALD mice. In addition, a novel peptide designed to include a region that binds to the catalytic site of MMP14 suppressed CD44 activation and attenuated alcohol-induced liver injury, including fibrosis, in mice.

CONCLUSIONS

These results demonstrate that TSG-6 attenuates alcohol-induced liver damage and fibrosis by blocking CD44 cleavage to CD44ICD and suggest that TSG-6 and TSG-6-mimicking peptide could be used as therapeutics for ALD with fibrosis.

Preliminary study on the diagnostic value of LEAP-2 and CK18 in biopsy-proven MAFLD

Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD) has become the leading cause of chronic liver disease. Liver biopsy, as the diagnostic gold standard, is invasive and has sampling bias, making it particularly important to search for sensitive and specific biomarkers for diagnosis. Cytokeratin 18 (CK18) M30 and M65 are products of liver cell apoptosis and necrosis, respectively, and liver-expressed antimicrobial peptide 2 (LEAP-2) is a related indicator of glucose and lipid metabolism. Correlation studies have found that all three indicators positively correlate with the liver enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Through comparison of diagnostic values, it was found that CK18 M65 can better distinguish between healthy individuals and MAFLD; LEAP-2 can effectively distinguish MAFLD from other liver diseases, especially ALD.

Landscape of extrachromosomal circular DNAs, transcriptome, and proteome analysis reveals insights into alcoholic liver cirrhosis

Alcoholic liver cirrhosis (ALC) is a result of excessive and chronic alcohol consumption. Because alchol can cause DNA damage, extrachromosomal circular DNA (eccDNA) was investigated in ALC liver due to it can be a result of DNA damage. Considering eccDNA has ability to lead to genomic instability as an enhancer of gene transcription, we utilized Circle-Seq to identify differences in eccDNA profiles and gene expression patterns in liver samples obtained from ALC patients (n = 3) and healthy controls (n = 3) to investigate the role of eccDNA in the development of ALC. The abundance of eccDNA in ALC (mean = 13,349) were higher than the healthy control (mean = 11,557) without significant difference (pvalue = 0.6530). We observed 1,032 eccDNA containing genes showed higher expression in ALC patients compared to healthy controls (p < 0.05, log2FC > 1). Notably, we discovered seven genes that exhibited a significant positive correlation between eccDNA abundance and gene expression levels. These genes include A disintegrin and metalloproteinase with thrombospondin motifs 2 (ADAMTS2), Voltage-dependent L-type calcium channel subunit alpha-1C (CACNA1C), Protein TANC1 (TANC1), Integrin alpha-2 (ITGA2), EH domain-containing protein 4 (EHD4), Phosphofurin acidic cluster sorting protein 1 (PACS1), and Neuron navigator 2 (NAV2). Through mass spectrometry proteomics, ITGA2 were found to have significantly higher abbudance in ALC. Integrins are a family of proteins plays key roles in the fibrosis development of liver. Thus, our study opens a new perspective for liver fibrosis development.

Ultrasonographic Assessment of Tissue Stiffness: Recent Progress in Transient Elastography and Shear Wave Elastography in the Liver and Various Organs

Ultrasonography is a noninvasive and widely accessible modality in clinical practice. Recently, ultrasonography has been used to evaluate tissue stiffness; the two representative techniques are transient elastography (FibroScan®) and shear wave elastography. These modalities are now generally used for the assessment of liver fibrosis, the prediction of hepatocarcinogenesis, and determining prognosis. In addition, shear wave elastography is available, not only for the liver but also for various other organs, including the breast and brain. In the breast and brain, shear wave elastography distinguishes malignant lesions from benign ones. Moreover, shear wave elastography can be useful for differentiating between ischemic and hemorrhagic strokes. This review summarizes the recent progress in transient elastography and shear wave elastography of the liver and introduces the advantages of ultrasonographic assessment of tissue stiffness in various organs, including the breast, brain, kidney, heart, thyroid, pancreas, muscle, and bone.

Selective Targeting of α4β7/MAdCAM-1 Axis Suppresses Fibrosis Progression by Reducing Proinflammatory T Cell Recruitment to the Liver

Integrin α4β7+ T cells perpetuate tissue injury in chronic inflammatory diseases, yet their role in hepatic fibrosis progression remains poorly understood. Here, we report increased accumulation of α4β7+ T cells in the liver of people with cirrhosis relative to disease controls. Similarly, hepatic fibrosis in the established mouse model of CCl4-induced liver fibrosis was associated with enrichment of intrahepatic α4β7+ CD4 and CD8 T cells. Monoclonal antibody (mAb)-mediated blockade of α4β7 or its ligand mucosal addressin cell adhesion molecule (MAdCAM)-1 attenuated hepatic inflammation and prevented fibrosis progression in CCl4-treated mice. Improvement in liver fibrosis was associated with a significant decrease in the infiltration of α4β7+ CD4 and CD8 T cells, suggesting that α4β7/MAdCAM-1 axis regulates both CD4 and CD8 T cell recruitment to the fibrotic liver, and α4β7+ T cells promote hepatic fibrosis progression. Analysis of hepatic α4β7+ and α4β7- CD4 T cells revealed that α4β7+ CD4 T cells were enriched for markers of activation and proliferation, demonstrating an effector phenotype. The findings suggest that α4β7+ T cells play a critical role in promoting hepatic fibrosis progression, and mAb-mediated blockade of α4β7 or MAdCAM-1 represents a promising therapeutic strategy for slowing hepatic fibrosis progression in chronic liver diseases.

Alcohol-associated liver cancer

Heavy alcohol intake induces a wide spectrum of liver diseases ranging from steatosis, steatohepatitis, cirrhosis, and HCC. Although alcohol consumption is a well-known risk factor for the development, morbidity, and mortality of HCC globally, alcohol-associated hepatocellular carcinoma (A-HCC) is poorly characterized compared to viral hepatitis-associated HCC. Most A-HCCs develop after alcohol-associated cirrhosis (AC), but the direct carcinogenesis from ethanol and its metabolites to A-HCC remains obscure. The differences between A-HCC and HCCs caused by other etiologies have not been well investigated in terms of clinical prognosis, genetic or epigenetic landscape, molecular mechanisms, and heterogeneity. Moreover, there is a huge gap between basic research and clinical practice due to the lack of preclinical models of A-HCC. In the current review, we discuss the pathogenesis, heterogeneity, preclinical approaches, epigenetic, and genetic profiles of A-HCC, and discuss the current insights into and the prospects for future research on A-HCC. The potential effect of alcohol on cholangiocarcinoma and liver metastasis is also discussed.

Alcohol-Associated Liver Disease Outcomes: Critical Mechanisms of Liver Injury Progression

Alcohol-associated liver disease (ALD) is a substantial cause of morbidity and mortality worldwide and represents a spectrum of liver injury beginning with hepatic steatosis (fatty liver) progressing to inflammation and culminating in cirrhosis. Multiple factors contribute to ALD progression and disease severity. Here, we overview several crucial mechanisms related to ALD end-stage outcome development, such as epigenetic changes, cell death, hemolysis, hepatic stellate cells activation, and hepatic fatty acid binding protein 4. Additionally, in this review, we also present two clinically relevant models using human precision-cut liver slices and hepatic organoids to examine ALD pathogenesis and progression.

Baicalin and N-acetylcysteine regulate choline metabolism via TFAM to attenuate cadmium-induced liver fibrosis

(Background): Cadmium is an environmental pollutant associated with several liver diseases. Baicalin and N-Acetylcysteine have antioxidant and hepatoprotective effects. (Purpose): However, it is unclear whether baicalin and N-Acetylcysteine can alleviate Cadmium -induced liver fibrosis by regulating metabolism, or whether they exert a synergistic effect. (Study design): We treated Cadmium-poisoned mice with baicalin, N-Acetylcysteine, or baicalin+ N-Acetylcysteine. We studied the effects of baicalin and N-Acetylcysteine on Cadmium-induced liver fibers and their specific mechanisms. (Methods): We used C57BL/6 J mice, and AML12, and HSC-6T cells to establish in vitro assays and in vivo models. (Results): Metabolomics was used to detect the effect of baicalin and N-Acetylcysteine on liver metabolism, which showed that compared with the control group, the Cadmium group had increased fatty acid and amino acid levels, with significantly reduced choline and acetylcholine contents. Baicalin and N-Acetylcysteine alleviated these Cadmium-induced metabolic changes. We further showed that choline alleviated Cadmium -induced liver inflammation and fibrosis. In addition, cadmium significantly promoted extracellular leakage of lactic acid, while choline alleviated the cadmium -induced destruction of the cell membrane structure and lactic acid leakage. Western blotting showed that cadmium significantly reduced mitochondrial transcription factor A (TFAM) and Choline Kinase α(CHKα2) levels, and baicalin and N-Acetylcysteine reversed this effect. Overexpression of Tfam in mouse liver and AML12 cells increased the expression of CHKα2 and the choline content, alleviating and cadmium-induced lactic acid leakage, liver inflammation, and fibrosis. (Conclusion): Overall, baicalin and N-Acetylcysteine alleviated cadmium-induced liver damage, inflammation, and fibrosis to a greater extent than either drug alone. TFAM represents a target for baicalin and N-Acetylcysteine, and alleviated cadmium-induced liver inflammation and fibrosis by regulating hepatic choline metabolism.

Canonical Wnt signaling promotes HSC glycolysis and liver fibrosis through an LDH-A/HIF-1α transcriptional complex

BACKGROUND AND AIMS

Aerobic glycolysis reprogramming occurs during HSC activation, but how it is initiated and sustained remains unknown. We investigated the mechanisms by which canonical Wnt signaling regulated HSC glycolysis and the therapeutic implication for liver fibrosis.

APPROACH AND RESULTS

Glycolysis was examined in HSC-LX2 cells upon manipulation of Wnt/β-catenin signaling. Nuclear translocation of lactate dehydrogenase A (LDH-A) and its interaction with hypoxia-inducible factor-1α (HIF-1α) were investigated using molecular simulation and site-directed mutation assays. The pharmacological relevance of molecular discoveries was intensified in primary cultures, rodent models, and human samples. HSC glycolysis was enhanced by Wnt3a but reduced by β-catenin inhibitor or small interfering RNA (siRNA). Wnt3a-induced rapid transactivation and high expression of LDH-A dependent on TCF4. Wnt/β-catenin signaling also stimulated LDH-A nuclear translocation through importin β2 interplay with a noncanonical nuclear location signal of LDH-A. Mechanically, LDH-A bound to HIF-1α and enhanced its stability by obstructing hydroxylation-mediated proteasome degradation, leading to increased transactivation of glycolytic genes. The Gly28 residue of LDH-A was identified to be responsible for the formation of the LDH-A/HIF-1α transcription complex and stabilization of HIF-1α. Furthermore, LDH-A-mediated glycolysis was required for HSC activation in the presence of Wnt3a. Results in vivo showed that HSC activation and liver fibrosis were alleviated by HSC-specific knockdown of LDH-A in mice. β-catenin inhibitor XAV-939 mitigated HSC activation and liver fibrosis, which were abrogated by HSC-specific LDH-A overexpression in mice with fibrosis.

CONCLUSIONS

Inhibition of HSC glycolysis by targeting Wnt/β-catenin signaling and LDH-A had therapeutic promise for liver fibrosis.

Bacillus coagulans regulates gut microbiota and ameliorates the alcoholic-associated liver disease in mice

Introduction

Alcoholic-associated liver diseases (ALD) are now widespread issues worldwide. Alcoholic-induced chronic dysbiosis of the gut microbiota is one of the factors in the pathophysiology of ALD.

Methods

In this work, we employed a chronic-binge ethanol feeding mice model, as described in a previous report.

Results

Our findings demonstrate that hepatic inflammatory injury damage and accumulation of fat can be effectively reduced in mice with ALD by altering the gut microbiota utilizing Bacillus coagulans. Treatment with B. coagulans significantly modulates the levels of TNF-α, IL-1β, and IL-22 cytokines while maintaining tight junction proteins and mucin protein expressions to support intestinal barrier function restoration. Treatment with B. coagulans also alters the composition of the gut microbiota and increases the production of short-chain fatty acids (SCFAs).

Discussion

This is mostly due to B. coagulans promotes the growth of bacteria that produce SCFAs, such as Ruminococcus species and Akkermansia, while inhibiting the growth of pathogenic bacteria like Escherichia Shigella. Moreover, treatment with B. coagulans causes levels of 2-Ketobutyric acid, ketoleucine, and indoleacetic acid increase while homovanillic acid and 3'-O-Methylguanosine metabolites decrease significantly. This study facilitates the development of therapeutic and preventive strategies for ALD using lactic acid bacteria.

What are the common downstream molecular events between alcoholic and nonalcoholic fatty liver?

Liver fat storage, also called hepatic steatosis, is increasingly common and represents a very frequent diagnosis in the medical field. Excess fat is not without consequences. In fact, hepatic steatosis contributes to the progression toward liver fibrosis. There are two main types of fatty liver disease, alcoholic fatty liver disease (AFLD) and nonalcoholic fatty liver disease (NAFLD). Although AFLD and NAFLD are similar in their initial morphological features, both conditions involve the same evolutive forms. Moreover, there are various common mechanisms underlying both diseases, including alcoholic liver disease and NAFLD, which are commonalities. In this Review, the authors explore similar downstream signaling events involved in the onset and progression of the two entities but not completely different entities, predominantly focusing on the gut microbiome. Downstream molecular events, such as the roles of sirtuins, cytokeratins, adipokines and others, should be considered. Finally, to complete the feature, some new tendencies in the therapeutic approach are presented.

miR-26a is a Key Therapeutic Target with Enormous Potential in the Diagnosis and Prognosis of Human Disease

MicroRNA-26a (miR-26a) belongs to small non-coding regulatory RNA molecules emerging as fundamental post-transcriptional regulators inhibiting gene expression that plays vital roles in various processes of human diseases such as depression, renal ischemia and reperfusion injury, liver injury and some refractory cancer. In this review, we expound on the results of studies about miR-26a with emphasis on its function in animal models or in vitro cell culture to simulate the most common human disease in the clinic. Furthermore, we also illustrate the underlying mechanisms of miR-26a in strengthening the antitumor activity of antineoplastic drugs. Importantly, dysregulation of miR-26a has been related to many chronic and malignant diseases, especially in neurological disorders in the brain such as depression and neurodegenerative diseases as well as cancers such as papillary thyroid carcinoma, hepatocellular carcinoma and so on. It follows that miR-26a has a strong possibility to be a potential therapeutic target for the treatment of neurological disorders and cancers. Although the research of miRNAs has made great progress in the last few decades, much is yet to be discovered, especially regarding their underlying mechanisms and roles in the complex diseases of humans. Consequently, miR-26a has been analyzed in chronic and malignant diseases, and we discuss the dysregulation of miR-26a and functional roles in the development and pathogenesis of these diseases, which is very helpful for understanding their mechanisms as new biomarkers for diagnosing and curing diseases in the near future.

Circular RNAs in non-alcoholic fatty liver disease: Functions and clinical significance

Nonalcoholic fatty liver disease (NAFLD), which affects approximately 25% of the global population, is an urgent health issue leading to various metabolic comorbidities. Circular RNAs (circRNAs), covalently closed RNA molecules, are characterized by ubiquity, diversity, stability, and conservatism. Indeed, they participate in various biological processes via distinct mechanisms that could modify the natural history of NAFLD. In this review, we briefly introduce the biogenesis, characteristics, and biological functions of circRNAs. Furthermore, we summarize circRNAs expression profiles in NAFLD by intersecting seven sequencing data sets and describe the cellular roles of circRNAs and their potential advantages as biomarkers of NAFLD. In addition, we emphatically discuss the exosomal non-coding RNA sorting mechanisms and possible functions in recipient cells. Finally, we extensively discuss the potential application of targeting disease-related circRNAs and competing endogenous RNA networks through gain-of-function and loss-of-function approaches in targeted therapy of NAFLD.

MUP1 mediates urolithin A alleviation of chronic alcohol-related liver disease via gut-microbiota-liver axis

Alcohol-related liver disease (ALD) is recognized as a global health crisis, contributing to approximately 20% of liver cancer-associated fatalities. Dysbiosis of the gut microbiome is associated with the development of ALD, with the gut microbial metabolite urolithin A (UA) exhibiting a potential for alleviating liver symptoms. However, the protective efficacy of UA against ALD and its underlying mechanism mediated by microbiota remain elusive. In this study, we provide evidence demonstrating that UA effectively ameliorates alcohol-induced metabolic disorders and hepatic endoplasmic reticulum (ER) stress through a specific gut-microbiota-liver axis mediated by major urinary protein 1 (MUP1). Moreover, UA exhibited the potential to restore alcohol-induced dysbiosis of the intestinal microbiota by enriching the abundance of Bacteroides sartorii (B. sartorii), Parabacteroides distasonis (P. distasonis), and Akkermansia muciniphila (A. muciniphila), along with their derived metabolite propionic acid. Partial attenuation of the hepatoprotective effects exerted by UA was observed upon depletion of gut microbiota using antibiotics. Subsequently, a fecal microbiota transplantation (FMT) experiment was conducted to evaluate the microbiota-dependent effects of UA in ALD. FMT derived from mice treated with UA exhibited comparable efficacy to direct UA treatment, as it effectively attenuated ER stress through modulation of MUP1. It was noteworthy that strong associations were observed among the hepatic MUP1, gut microbiome, and metabolome profiles affected by UA. Intriguingly, oral administration of UA-enriched B. sartorii, P. distasonis, and A. muciniphila can enhance propionic acid production to effectively suppress ER stress via MUP1, mimicking UA treatment. Collectively, these findings elucidate the causal mechanism that UA alleviated ALD through the gut-microbiota-liver axis. This unique mechanism sheds light on developing novel microbiome-targeted therapeutic strategies against ALD.

Liver biopsy for assessment of suspected drug-induced liver injury in metabolic dysfunction-associated steatohepatitis clinical trials: Expert consensus from the Liver Forum

BACKGROUND

Causality assessment of suspected drug-induced liver injury (DILI) during metabolic dysfunction-associated steatohepatitis (MASH) clinical trials can be challenging, and liver biopsies are not routinely performed as part of this evaluation. While the field is moving away from liver biopsy as a diagnostic and prognostic tool, information not identified by non-invasive testing may be provided on histology.

AIM

To address the appropriate utilisation of liver biopsy as part of DILI causality assessment in this setting.

METHODS

From 2020 to 2022, the Liver Forum convened a series of webinars on issues pertaining to liver biopsy during MASH trials. The Histology Working Group was formed to generate a series of consensus documents addressing these challenges. This manuscript focuses on liver biopsy as part of DILI causality assessment.

RESULTS

Expert opinion, guidance and recommendations on the role of liver biopsy as part of causality assessment of suspected DILI occurring during clinical trials for a drug(s) being developed for MASH are provided. Lessons learned from prior MASH programs are reviewed and gaps identified.

CONCLUSIONS

Although there are no pathognomonic features, histologic evaluation of suspected DILI during MASH clinical trials may alter patient management, define the pattern and severity of injury, detect findings that favour a diagnosis of DILI versus MASH progression, identify prognostic features, characterise the clinicopathological phenotype of DILI, and/or define lesions that influence decisions about trial discontinuation and further development of the drug.

Overall and individual associations between per- and polyfluoroalkyl substances and liver function indices and the metabolic mechanism

Per- and polyfluoroalkyl substances (PFAS) can disrupt liver homeostasis. Studies have shown that a single exposure to PFAS may provoke abnormal liver function; however, few studies have investigated the overall effect of PFAS mixtures. We aimed to investigate associations between exposure to PFAS mixtures and liver function indices and explore the relevant mechanisms. This study included 278 adult males from Guangzhou, China. Serum metabolite profiles were analyzed using untargeted metabolomics. We applied weighted quantile sum (WQS) regression as well as Bayesian kernel machine regression (BKMR) to analyze the association of nine PFAS mixtures with 14 liver function indices. PFAS mixtures were positively associated with apolipoprotein B (APOB) and gamma-glutamyltransferase (GGT) and negatively associated with direct bilirubin (DBIL) and total bilirubin (TBIL) in both the WQS and BKMR analyses. In addition, Spearman's correlation test showed individual PFAS correlated with APOB, GGT, TBIL, and DBIL, while there's little correlation between individual PFAS and other liver function indices. In linear regression analysis, PFHxS, PFOS, PFHpS, PFNA, PFDA, and PFUdA were associated with APOB; PFOA, PFDA, PFOS, PFNA, and PFUdA were associated with GGT. Subsequently, a metabolome-wide association study and mediation analysis were combined to explore metabolites that mediate these associations. The mechanisms linking PFAS to APOB and GGT are mainly related with amino acid and glycerophospholipid metabolism. High-dimensional mediation analysis showed that glycerophospholipids are the main markers of the association between PFAS and APOB, and that (R)-dihydromaleimide, Ile Leu, (R)-(+)-2-pyrrolidone-5-carboxylic acid, and L-glutamate are the main markers of the association between PFAS and GGT. In summary, overall associations between PFAS and specific indices of liver function were found using two statistical methods; the metabolic pathways and markers identified here may serve to prompt more detailed study in animal-based systems, as well as a similar detailed analysis in other populations.

Gut liver brain axis in diseases: the implications for therapeutic interventions

Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract, liver, and nervous systems. In the past few decades, breakthrough progress has been made in the gut liver brain axis, mainly through understanding its formation mechanism and increasing treatment strategies. In this review, we discuss various complex networks including barrier permeability, gut hormones, gut microbial metabolites, vagus nerve, neurotransmitters, immunity, brain toxic metabolites, β-amyloid (Aβ) metabolism, and epigenetic regulation in the gut-liver-brain axis. Some therapies containing antibiotics, probiotics, prebiotics, synbiotics, fecal microbiota transplantation (FMT), polyphenols, low FODMAP diet and nanotechnology application regulate the gut liver brain axis. Besides, some special treatments targeting gut-liver axis include farnesoid X receptor (FXR) agonists, takeda G protein-coupled receptor 5 (TGR5) agonists, glucagon-like peptide-1 (GLP-1) receptor antagonists and fibroblast growth factor 19 (FGF19) analogs. Targeting gut-brain axis embraces cognitive behavioral therapy (CBT), antidepressants and tryptophan metabolism-related therapies. Targeting liver-brain axis contains epigenetic regulation and Aβ metabolism-related therapies. In the future, a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.

Overview of hepatocellular carcinoma: from molecular aspects to future therapeutic options

Hepatocellular carcinoma (HCC) is the seventh most highly prevalent malignant tumor globally and the second most common cause of mortality. HCC develops with complex pathways that occur through multistage biological processes. Non-alcoholic fatty liver disease, metabolic-associated fatty liver disease, alcoholic liver disease, autoimmune hepatitis, hepatitis B, and hepatitis C are the causative etiologies of HCC. HCC develops as a result of epigenetic changes, protein-coding gene mutations, and altered signaling pathways. Biomarkers and potential therapeutic targets for HCC open up new possibilities for treating the disease. Immune checkpoint inhibitors are included in the treatment options in combination with molecular targeted therapy.

MiRNAs in Alcohol-Related Liver Diseases and Hepatocellular Carcinoma: A Step toward New Therapeutic Approaches?

Alcohol-related Liver Disease (ALD) is the primary cause of chronic liver disorders and hepatocellular carcinoma (HCC) development in developed countries and thus represents a major public health concern. Unfortunately, few therapeutic options are available for ALD and HCC, except liver transplantation or tumor resection for HCC. Deciphering the molecular mechanisms underlying the development of these diseases is therefore of major importance to identify early biomarkers and to design efficient therapeutic options. Increasing evidence indicate that epigenetic alterations play a central role in the development of ALD and HCC. Among them, microRNA importantly contribute to the development of this disease by controlling the expression of several genes involved in hepatic metabolism, inflammation, fibrosis, and carcinogenesis at the post-transcriptional level. In this review, we discuss the current knowledge about miRNAs' functions in the different stages of ALD and their role in the progression toward carcinogenesis. We highlight that each stage of ALD is associated with deregulated miRNAs involved in hepatic carcinogenesis, and thus represent HCC-priming miRNAs. By using in silico approaches, we have uncovered new miRNAs potentially involved in HCC. Finally, we discuss the therapeutic potential of targeting miRNAs for the treatment of these diseases.

FIB-4 as a Time-varying Covariate and Its Association With Severe Liver Disease in Primary Care: A Time-dependent Cox Regression Analysis

BACKGROUND AND GOALS

The Fibrosis-4 Index (FIB-4) has demonstrated a strong association with severe liver disease (SLD) outcomes in primary care, but previous studies have only evaluated this relationship using 1 or 2 FIB-4 scores. In this study, we determined the association of FIB-4 as a time-varying covariate with SLD risk using time-dependent Cox regression models.

STUDY

This retrospective cohort study included primary care patients with at least 2 FIB-4 scores between 2012 and 2021. The outcome was the occurrence of an SLD event, a composite of cirrhosis, complications of cirrhosis, hepatocellular carcinoma, and liver transplantation. The primary predictor was FIB-4 advanced fibrosis risk, categorized as low-(<1.3), indeterminate-(1.3≤FIB to 4<2.67), and high-risk (≥2.67). FIB-4 scores were calculated and the index, last, and maximum FIB-4s were identified. Time-dependent Cox regression models were used to estimate hazard ratios (HR) and their corresponding 95% CI with adjustment for potentially confounding covariates.

RESULTS

In the cohort, 20,828 patients had a median of 5 (IQR: 3 to 11) FIB-4 scores each and 3% (n=667) suffered an SLD outcome during follow-up. Maximum FIB-4 scores were indeterminate-risk for 34% (7149) and high-risk for 24% (4971) of the sample, and 32% (6692) of patients had an increase in fibrosis risk category compared with their index value. The adjusted Cox regression model demonstrated an association between indeterminate- (hazard ratio 3.21; 95% CI 2.33-4.42) and high-risk (hazard ratio 20.36; 95% CI 15.03-27.57) FIB-4 scores with SLD outcomes.

CONCLUSIONS

Multiple FIB-4 values per patient are accessible in primary care, FIB-4 fibrosis risk assessments change over time, and high-risk FIB-4 scores (≥2.67) are strongly associated with severe liver disease outcomes when accounting for FIB-4 as a time-varying variable.

ROS/RNS as molecular signatures of chronic liver diseases

The liver can succumb to oxidant damage during the development of chronic liver diseases. Despite their physiological relevance to hepatic homeostasis, excessive reactive oxygen/nitrogen species (ROS/RNS) production under pathological conditions is detrimental to all liver constituents. Chronic oxidative stress coupled to unresolved inflammation sets in motion the activation of profibrogenic hepatic stellate cells (HSCs) and later pathogenesis of liver fibrosis, cirrhosis, and liver cancer. The liver antioxidant and repair systems, along with autophagic and ferroptotic machineries, are implicated in the onset and trajectory of disease development. In this review, we discuss the ROS/RNS-related mechanisms underlying liver fibrosis of distinct etiologies and highlight preclinical and clinical trials of antifibrotic therapies premised on remediating oxidative/nitrosative stress in hepatocytes or targeting HSC activation.

Alcohol-Associated Liver Disease: Evolving Concepts and Treatments

Alcohol is a prominent cause of liver disease worldwide with higher prevalence in developed nations. The spectrum of alcohol-associated liver disease (ALD) encompasses a diverse range of clinical entities, from asymptomatic isolated steatosis to decompensated cirrhosis, and in some cases, acute or chronic liver failure. Consequently, it is important for healthcare practitioners to maintain awareness and systematically screen for ALD. The optimal evaluation and management of ALD necessitates a collaborative approach, incorporating a multidisciplinary team and accounting for concurrent medical conditions. A repertoire of therapeutic interventions exists to support patients in achieving alcohol cessation and sustaining remission, with complete abstinence being the ultimate objective. This review explores the existing therapeutic options for ALD acknowledging geographical discrepancies in accessibility. Recent innovations, including the inclusion of alcohol consumption biomarkers into clinical protocols and the expansion of liver transplantation eligibility to encompass severe alcohol-associated hepatitis, are explored.

Cytotoxic NK cells phenotype and activated lymphocytes are the main characteristics of patients with alcohol-associated liver disease

T cells, natural killer (NK) and NKT cells have opposing actions in the development of alcohol-associated liver fibrosis. We aimed to evaluate the phenotype of NK cells, NKT cells and activated T cells in patients with alcohol use disorder (AUD) according to the presence of advanced liver fibrosis (ALF). Totally, 79 patients (51-years, 71% males) were admitted to treatment of AUD. ALF was defined as FIB4-score > 2.67. Immunophenotyping of NK cells (CD3-CD56+CD16+, CD3-CD56+CD16-, CD3-CD56-CD16+), NKT-like (CD3+CD56+), and the activation status of CD4+, CD8+ and regulatory T cells (Tregs) were evaluated according to the HLA-DR expression. Patients had an AUD duration of 18 ± 11 years with a daily alcohol consumption of 155 ± 77 gr/day prior to hospital admission. The values of absolute cells were 2 ± 0.9 cells/L for total lymphocytes, 1054 ± 501 cells/µL for CD4+, 540 ± 335 cells/µL for CD8+, 49.3 ± 24.8 cells/µL for Tregs, 150.3 ± 97.5 cells/µL for NK cells and 69.8 ± 78.3 cells/µL for NKT-like. The percentage of total NK cells (11.3 ± 5.5% vs. 7 ± 4.3%, p < 0.01), CD3-CD56+CD16+ regarding total lymphocytes (9.7 ± 5.1% vs. 5.8 ± 3.9%, p < 0.01), activated CD4+ cells (5.2 ± 3.2% vs. 3.9 ± 3%, p = 0.04) and activated CD8+ cells (15.7 ± 9.1% vs. 12.2 ± 9%, p = 0.05) were significantly higher in patients with ALF. The percentage of CD3-CD56+CD16- regarding NK cells (5.1 ± 3.4% vs. 7.6 ± 6.2%, p = 0.03) was significantly lower in patients with ALF. Activated Tregs (39.9 ± 11.5 vs. 32.4 ± 9.2, p = 0.06) showed a tendency to be higher in patients with ALF. The proportion of activated CD4+ cells (r = 0.40, p < 0.01) and activated CD8+ cells (r = 0.51, p < 0.01) was correlated with the proportion of NKT-like in patients without ALF. Patients with ALF presented an increased NK cytotoxic phenotype and activated T cells concomitant with a decreased NK cytokine-secreting phenotype.

Mechanotransductive receptor Piezo1 as a promising target in the treatment of fibrosis diseases

Fibrosis could happen in every organ, leading to organic malfunction and even organ failure, which poses a serious threat to global health. Early treatment of fibrosis has been reported to be the turning point, therefore, exploring potential correlates in the pathogenesis of fibrosis and how to reverse fibrosis has become a pressing issue. As a mechanism-sensitive cationic calcium channel, Piezo1 turns on in response to changes in the lipid bilayer of the plasma membrane. Piezo1 exerts multiple biological roles, including inhibition of inflammation, cytoskeletal stabilization, epithelial-mesenchymal transition, stromal stiffness, and immune cell mechanotransduction, interestingly enough. These processes are closely associated with the development of fibrotic diseases. Recent studies have shown that deletion or knockdown of Piezo1 attenuates the onset of fibrosis. Therefore, in this paper we comprehensively describe the biology of this gene, focusing on its potential relevance in pulmonary fibrosis, renal fibrosis, pancreatic fibrosis, and cardiac fibrosis diseases, except for the role of drugs (agonists), increased intracellular calcium and mechanical stress using this gene in alleviating fibrosis.

The Effect of Boric Acid and Sodium Pentaborate Pentahydrate-Treated Foreskin Derived Mesenchymal Stem Cells on Liver Fibrosis

Liver fibrosis is a worldwide public health problem due to its life-threatening complications, including portal hypertension, liver failure, cirrhosis, and hepatocellular carcinoma (HCC). Liver fibrosis is the net result of a complex excessive accumulation of extracellular matrix (ECM). Activation of hepatic stellate cells (HSCs) are the cause of deposition of ECM and are commonly recognized as a key step in liver fibrosis. The aim of this study was to investigate the effect of foreskin-derived mesenchymal stem cells treated with boron compounds on liver fibrosis. Rats were injected intraperitoneally with thioacetamide (TAA) at a dose of 150 mg/kg except sham and control groups' rats. Thioacetamide (TAA), foreskin-derived mesenchymal stem cells (TAA + FSDMSC), FSDMSC treated with boric acid (TAA + FSDMSC + BA), FSDMSC treated with sodium pentaborate pentahydrate (TAA + FSDMSC + NaB), control and sham groups were studied. Boron compound treated foreskin-derived mesenchymal stem cells were injected into the tail vein, and evaluations were conducted after 4 weeks and liver tissues were obtained for structural, immunohistochemical, and western blot studies and blood samples were taken for biochemical analysis. FSDMSC (BA) alleviates TAA-induced rats liver fibrosis, and BA showed a positive effect on foreskin-derived mesenchymal stem cells viability. After using BA-treated mesenchymal stem cells, we observed that there was regression in the fibrotic areas at TAA-induced liver fibrosis. The result demonstrates that the contribution of TAA + FSDMSC and TAA + FSDMSC (NaB) at the level of structure is not effective in regression of fibrosis in TAA-generated liver fibrosis. We concluded that FSDMSC treated with BA may be a factor in the regression of fibrosis.

Recent progress in the effect of ferroptosis of HSCs on the development of liver fibrosis

Fibrosis is a common pathological process that must take place for multiple chronic liver diseases to develop into cirrhosis and liver cancer. Liver fibrosis (LF) is regulated by various cytokines and signaling pathways in its occurrence and development. Ferroptosis is an important mode of cell death caused by iron-dependent oxidative damage and is regulated by iron metabolism and lipid peroxidation signaling pathways. In recent years, numerous studies have shown that ferroptosis is closely related to LF. As the main material secreted by the extracellular matrix, hepatic stellate cells (HSCs) are a general concern in the development of LF. Therefore, targeting HSC ferroptosis against LF is crucial. This review describes the current status of treating LF by inducing HSC ferroptosis that would aid studies in better understanding the current knowledge on ferroptosis in HSCs and the future research direction in this field.

Therapeutic inhibition of miR-155 attenuates liver fibrosis via STAT3 signaling

Most chronic liver diseases progress to liver fibrosis, which, when left untreated, can lead to cirrhosis and hepatocellular carcinoma. MicroRNA (miRNA)-targeted therapeutics have become attractive approaches to treat diseases. In this study, we investigated the therapeutic effect of miR-155 inhibition in the bile duct ligation (BDL) mouse model of liver fibrosis and evaluated the role of miR-155 in chronic liver fibrosis using miR-155-deficient (miR-155 knockout [KO]) mice. We found increased hepatic miR-155 expression in patients with cirrhosis and in the BDL- and CCl4-induced mouse models of liver fibrosis. Liver fibrosis was significantly reduced in miR-155 KO mice after CCl4 administration or BDL. To assess the therapeutic potential of miR-155 inhibition, we administered an rAAV8-anti-miR-155 tough decoy in vivo that significantly reduced liver damage and fibrosis in BDL. BDL-induced protein levels of transforming growth factor β (TGF-β), p-SMAD2/3, and p-STAT3 were attenuated in anti-miR-155-treated compared with control mice. Hepatic stellate cells from miR-155 KO mice showed attenuation in activation and mesenchymal marker expression. In vitro, miR-155 gain- and loss-of-function studies revealed that miR-155 regulates activation of stellate cells partly via STAT3 signaling. Our study suggests that miR-155 is the key regulator of liver fibrosis and might be a potential therapeutic target to attenuate fibrosis progression.

Targeting collagen homeostasis for the treatment of liver fibrosis: Opportunities and challenges

Liver fibrosis is an excessive production, aberrant deposition, and deficit degradation of extracellular matrix (ECM). Patients with unresolved fibrosis ultimately undergo end-stage liver diseases. To date, the effective and safe strategy to cease fibrosis progression remains an unmet clinical need. Since collagens are the most abundant ECM protein which play an essential role in fibrogenesis, the suitable regulation of collagen homeostasis could be an effective strategy for the treatment of liver fibrosis. Therefore, this review provides a brief overview on the dysregulation of ECM homeostasis, focusing on collagens, in the pathogenesis of liver fibrosis. Most importantly, promising therapeutic mechanisms related to biosynthesis, deposition and extracellular interactions, and degradation of collagens, together with preclinical and clinical antifibrotic evidence of drugs affecting each target are orderly criticized. In addition, challenges for targeting collagen homeostasis in the treatment of liver fibrosis are discussed.

Blocking ATP-P1Rs axis attenuate alcohol-related liver fibrosis

AIMS

The aim of this study was to explore the fibrogenic effects of ATP-P1Rs axis and ATP-P2Rs axis on alcohol-related liver fibrosis (ALF).

MATERIALS AND METHODS

C57BL/6J CD73 knock out (KO) mice were used in our study. 8-12 weeks male mice were used as an ALF model in vivo. In conclusion, after one week of adaptive feeding, 5 % alcohol liquid diet was given for 8 weeks. High-concentration alcohol (31.5 %, 5 g/kg) was administered by gavage twice weekly, and 10 % CCl4 intraperitoneal injections (1 ml/kg) were administered twice weekly for the last two weeks. The mice in the control group were injected intraperitoneally with an equivalent volume of normal saline. Fasting for 9 h after the last injection, blood samples were collected, and related indicators were tested. In vitro, rat hepatic stellate cells (HSCs) were treated with 200 μM acetaldehyde to establish an alcoholic liver fibrosis for 48 h, then tested related indicators.

KEY FINDINGS

We found that both adenosine receptors including adenosine A1, A2A, A2B, A3 receptors (A1R, A2AR, A2BR, A3R) and ATP receptors including P2X7, P2Y2 receptors (P2X7R, P2Y2R) were expressed increased in ALF. After CD73 was knocked out, we found that adenosine receptors expression decreased, ATP expression increased, and fibrosis degree decreased.

SIGNIFICANCE

Based on the research, we discovered that adenosine plays a more important role in ALF. Therefore, blocking the ATP-P1Rs axis represented a potential treatment for ALF, and CD73 will become a potential therapeutic target.

Amniotic Membrane and Its Derivatives: Novel Therapeutic Modalities in Liver Disorders

The liver is a vital organ responsible for metabolic and digestive functions, protein synthesis, detoxification, and numerous other necessary functions. Various acute, chronic, and neoplastic disorders affect the liver and hamper its biological functions. Most of the untreated liver diseases lead to inflammation and fibrosis which develop into cirrhosis. The human amniotic membrane (hAM), the innermost layer of the fetal placenta, is composed of multiple layers that include growth-factor rich basement membrane, epithelial and mesenchymal stromal cell layers. hAM possesses distinct beneficial anti-fibrotic, anti-inflammatory and pro-regenerative properties via the secretion of multiple potent trophic factors and/or direct differentiation into hepatic cells which place hAM-based therapies as potential therapeutic strategies for the treatment of chronic liver diseases. Decellularized hAM is also an ideal scaffold for liver tissue engineering as this biocompatible niche provides an excellent milieu for cell proliferation and hepatocytic differentiation. Therefore, the current review discusses the therapeutic potential of hAM and its derivatives in providing therapeutic solutions for liver pathologies including acute liver failure, metabolic disorders, liver fibrosis as well as its application in liver tissue engineering.

Enhanced liver Fibrosis® test predicts liver-related outcomes in the general population

Background & Aims

The Enhanced Liver Fibrosis® (ELF) test exhibits good discriminative performance in detecting advanced liver fibrosis and in predicting liver-related outcomes in patients with specific liver diseases, but large population-based studies are missing. We analysed the predictive performance of the ELF test in a general population cohort.

Methods

Data were sourced from the Health 2000 study, a Finnish population-based health examination survey conducted in 2000-2001. Subjects with baseline liver disease were excluded. The ELF test was performed on blood samples collected at baseline. Data were linked with national healthcare registers for liver-related outcomes (hospitalisation, cancer, and death).

Results

The cohort comprised 6,040 individuals (mean age 52.7. 45.6% men) with 67 liver-related outcomes during a median 13.1-year follow-up. ELF predicted liver outcomes (unadjusted hazards ratio 2.70, 95% CI 2.16-3.38). with 5- and 10-year AUCs of 0.81 (95% CI 0.71-0.91) and 0.71 (95% CI 0.63-0.79) by competing-risk methodology. The 10-year risks for liver outcomes increased from 0.5% at ELF <9.8 to 7.1% at ELF ≥11.3, being higher among men than women at any given ELF level. Among individuals with body mass index ≥30 kg/m2, diabetes, or alanine aminotransferase >40 U/L. Five-year AUCs for ELF were 0.85, 0.87, and 0.88, respectively. The predictive ability of the ELF test decreased with time: the 10-year AUCs were 0.78, 0.69, and 0.82, respectively.

Conclusions

The ELF test shows good discriminative performance in predicting liver-related outcomes in a large general population cohort and appears particularly useful for predicting 5-year outcomes in persons with risk factors.

Impact and implications

The Enhanced Liver Fibrosis test exhibits good performance for predicting liver-related outcomes (hospitalisation, liver cancer, or liver-related death) in the general population, especially in those with risk factors.

Selective targeting of α 4 β 7 /MAdCAM-1 axis suppresses liver fibrosis by reducing proinflammatory T cell recruitment to the liver

Integrin α 4 β 7 + T cells perpetuate tissue injury in chronic inflammatory diseases, yet their role in hepatic fibrosis progression remains poorly understood. Here we report increased accumulation of α 4 β 7 + T cells in the liver of people with cirrhosis relative to disease controls. Similarly, hepatic fibrosis in the established mouse model of CCl 4 -induced liver fibrosis was associated with enrichment of intrahepatic α 4 β 7 + CD4 and CD8 T cells. Monoclonal antibody (mAb)-mediated blockade of α 4 β 7 or its ligand mucosal addressin cell adhesion molecule (MAdCAM)-1 attenuated hepatic inflammation and prevented fibrosis progression in CCl 4 treated mice. Improvement in liver fibrosis was associated with a significant decrease in the infiltration of α 4 β 7 + CD4 and CD8 T cells suggesting that α 4 β 7 /MAdCAM-1 axis regulates both CD4 and CD8 T cell recruitment to the fibrotic liver, and α 4 β 7 + T cells promote hepatic fibrosis progression. Analysis of hepatic α 4 β 7 + and α 4 β 7 -CD4 T cells revealed that α 4 β 7 + CD4 T cells enriched for markers of activation and proliferation demonstrating an effector phenotype. Notably, blockade of α 4 β 7 or MAdCAM-1 did not affect the recruitment of Foxp3+ regulatory T cells, demonstrating the specificity of α 4 β 7 /MAdCAM-1 axis in regulating effector T cell recruitment to the liver. The findings suggest that α 4 β 7 + T cells play a critical role in promoting hepatic fibrosis progression, and mAb-mediated blockade of α 4 β 7 or MAdCAM-1 represents a promising therapeutic strategy for slowing hepatic fibrosis progression in chronic liver diseases.

Role of Ferroptosis in Fibrosis Diseases

Ferroptosis is a pervasive non-apoptotic mode of cell death that is different from autophagy or necrosis. It is mainly caused by an imbalance between the production and degradation of lipid reactive oxygen species in cells. Several metabolic pathways and biochemical processes, such as amino acid and lipid metabolism, iron handling, and mitochondrial respiration, affect and regulate cell sensitivity to peroxidation and ferroptosis. Organ fibrosis, a pathological manifestation of several etiological conditions, leads to chronic tissue injury and is characterized by excessive deposition of extracellular matrix components. Excessive tissue fibrosis can have diverse pathophysiological effects on several organ systems, eventually causing organ dysfunction and failure. The current manuscript provides a review that illustrates the link between ferroptosis and organ fibrosis and to better understand the underlying mechanisms. It provides novel potential therapeutic approaches and targets for fibrosis diseases.

BRD4 promotes hepatic stellate cells activation and hepatic fibrosis via mediating P300/H3K27ac/PLK1 axis

Hepatic fibrosis (HF) is a reversible wound-healing response characterized by excessive extracellular matrix (ECM) deposition and secondary to persistent chronic injury. Bromodomain protein 4 (BRD4) commonly functions as a "reader" to regulate epigenetic modifications involved in various biological and pathological events, but the mechanism of HF remains unclear. In this study, we established a CCl₄-induced HF model and spontaneous recovery model in mice and found aberrant BRD4 expression, which was consistent with the results in human hepatic stellate cells (HSCs)- LX2 cells in vitro. Subsequently, we found that distriction and inhibition of BRD4 restrained TGFβ-induced trans-differentiation of LX2 cells into activated, proliferative myofibroblasts and accelerated apoptosis, and BRD4 overexpression blocked MDI-induced LX2 cells inactivation and promoted the proliferation and inhibited apoptosis of inactivated cells. Additionally, adeno-associated virus serotype 8-loaded short hairpin RNA-mediated BRD4 knockdown in mice significantly attenuated CCl₄-induced fibrotic responses including HSCs activation and collagen deposition. Mechanistically, BRD4 deficiency inhibited PLK1 expression in activated LX2 cells, and ChIP and Co-IP assays revealed that BRD4 regulation of PLK1 was dependent on P300-mediated acetylation modification for H3K27 on the PLK1 promoter. In conclusion, BRD4 deficiency in the liver alleviates CCl₄-induced HF in mice, and BRD4 participates in the activation and reversal of HSCs through positively regulating the P300/H3K27ac/PLK1 axis, providing a potential insight for HF therapy.

Blueberry and cranberry extracts mitigate CCL4-induced liver damage, suppressing liver fibrosis, inflammation and oxidative stress

The current study aims to evaluate potential hepatoprotective effect of lingonberry, cranberry and blueberry polyphenols on carbon tetrachloride (CCL-4)-induced acute and subacute liver injury in rats. A total of 55 male Wistar rats, divided into six experimental and control groups. With the exception of the negative control group, all groups received an intraperitoneal injection of CCl-4, twice a week for 14 days. An extract of lingonberry, cranberry, blueberry polyphenols and the positive control, silymarin were administered daily via intragastric route, for 14 consecutive days. The untreated control group showed characteristic of classical oxidative stress-mediated liver damage with vacuolization of the hepatocyte cytoplasm, infiltration by immune cells and proliferation of collagen fibers, decrease in body weight and increase in liver weight; increased levels of AST and ALT in serum, an increased lipid peroxidation in the liver. However, the use of cranberry and blueberry polyphenols significantly suppressed liver damage, exerting an effect comparable to the hepatoprotective effect of the positive control. The extracts prevented and reduced inflammatory liver damage by reducing IL-6, TNF-α and IFN-γ levels. In conclusion, blueberry and cranberry extracts have a protective effect against acute and subacute CCl4-induced hepatotoxicity in rats.

Extracellular volume fraction obtained by dual-energy CT depicting the etiological differences of liver fibrosis

PURPOSE

To assess etiological differences in extracellular volume fraction (ECV) and evaluate its influence on staging performance.

METHODS

A total of 166 patients with normal liver (n = 14) and chronic liver disease related to viral hepatitis (n = 71), alcohol (n = 44), and nonalcoholic steatohepatitis (NASH) (n = 37) underwent dual-energy CT (DECT) of the liver (5-min equilibrium-phase images) between January 2020 and July 2022. The iodine densities of the parenchyma and aorta were measured and ECV was calculated. Comparisons of ECV between each etiology and METAVIR fibrosis stage were statistically analyzed (p < 0.05).

RESULTS

ECV in each etiology and all patients significantly increased with higher fibrosis stage (p < 0.001) and showed a strong or moderate correlation with fibrosis stage (Spearman's ρ; all patients, 0.701; viral hepatitis, 0.638; alcoholic, 0.885; NASH, 0.791). In stages F2-F4, ECV in alcoholic liver disease was significantly larger than those for viral hepatitis and NASH (p < 0.05); however, no significant difference in stage F1 was found among the three etiologies. The cutoff values and areas under the receiver operating characteristic curve (AUC-ROCs) for discriminating fibrosis stage (≥ F1- ≥ F4) were higher for alcohol (cutoff values and AUC-ROC; 20.1% and 0.708 for ≥ F1, 23.8% and 0.990 for ≥ F2, 24.3% and 0.968 for ≥ F3, and 26.6% and 0.961 for ≥ F4, respectively) compared with those for the others.

CONCLUSION

ECV in alcoholic liver disease is higher than that in other etiologies in the advanced stages of fibrosis, and etiological differences in ECV affect the staging performance of fibrosis.

Candida albicans-specific Th17 cell-mediated response contributes to alcohol-associated liver disease

Alcohol-associated liver disease is accompanied by intestinal mycobiome dysbiosis, yet the impacts on liver disease are unclear. We demonstrate that Candida albicans-specific T helper 17 (Th17) cells are increased in circulation and present in the liver of patients with alcohol-associated liver disease. Chronic ethanol administration in mice causes migration of Candida albicans (C. albicans)-reactive Th17 cells from the intestine to the liver. The antifungal agent nystatin decreased C. albicans-specific Th17 cells in the liver and reduced ethanol-induced liver disease in mice. Transgenic mice expressing T cell receptors (TCRs) reactive to Candida antigens developed more severe ethanol-induced liver disease than transgene-negative littermates. Adoptively transferring Candida-specific TCR transgenic T cells or polyclonal C. albicans-primed T cells exacerbated ethanol-induced liver disease in wild-type mice. Interleukin-17 (IL-17) receptor A signaling in Kupffer cells was required for the effects of polyclonal C. albicans-primed T cells. Our findings indicate that ethanol increases C. albicans-specific Th17 cells, which contribute to alcohol-associated liver disease.

Sex differences in the associations of body size and body shape with platelets in the UK Biobank cohort

BACKGROUND

Obesity is accompanied by low-grade inflammation and leucocytosis and increases the risk of venous thromboembolism. Associations with platelet count, however, are unclear, because several studies have reported positive associations only in women. Associations with body shape are also unclear, because waist and hip circumferences reflect overall body size, as well as body shape, and are correlated strongly positively with body mass index (BMI).

METHODS

We evaluated body shape with the allometric body shape index (ABSI) and hip index (HI), which reflect waist and hip size among individuals with the same weight and height and are uncorrelated with BMI. We examined the associations of BMI, ABSI, and HI with platelet count, mean platelet volume (MPV), and platelet distribution width (PDW) in multivariable linear regression models for 125,435 UK Biobank women and 114,760 men. We compared men with women, post-menopausal with pre-menopausal women, and older (≥ 52 years) with younger (< 52 years) men.

RESULTS

BMI was associated positively with platelet count in women, more strongly in pre-menopausal than in post-menopausal, and weakly positively in younger men but strongly inversely in older men. Associations of BMI with platelet count were shifted towards the inverse direction for daily alcohol consumption and current smoking, resulting in weaker positive associations in women and stronger inverse associations in men, compared to alcohol ≤ 3 times/month and never smoking. BMI was associated inversely with MPV and PDW in pre-menopausal women but positively in post-menopausal women and in men. ABSI was associated positively with platelet count, similarly in women and men, while HI was associated weakly inversely only in women. ABSI was associated inversely and HI positively with MPV but not with PDW and only in women. Platelet count was correlated inversely with platelet size and positively with leucocyte counts, most strongly with neutrophils.

CONCLUSIONS

Competing factors determine the associations of BMI with platelet count. Factors with sexually dimorphic action (likely thrombopoietin, inflammatory cytokines, or cortisol), contribute to a positive association, more prominently in women than in men, while age-dependent factors (likely related to liver damage and fibrosis), contribute to an inverse association, more prominently in men than in women.

Life expectancy and healthy life expectancy of patients with advanced schistosomiasis in Hunan Province, China

BACKGROUND

Few studies have investigated the change in life expectancy (LE) and the healthy lifespan among patients with advanced schistosomiasis. This study was to evaluate the LE and healthy life expectancy (HLE) for patients and assess the mechanism responsible for the LE inequality.

METHODS

We utilized data from a dynamic advanced schistosomiasis cohort (10,362 patients) for the period from January 2008 to December 2019 in Hunan Province, China, to calculate the LEs of patients, and made a comparison with that of general population (19,642 schistosomiasis-free individuals) in the schistosomiasis endemic areas. LEs were estimated from 15 years of age by constructing period life tables. Arriaga's decomposition method was applied to quantify the influence of the age structure on the difference in LE. HLE for advanced schistosomiasis patients was calculated by using Sullivan method with age-specific disability weight. The LE and HLE were calculated for both males and females to perform further analyses on gender gap.

RESULTS

The estimated LE for advanced schistosomiasis patients aged 15-19 was 49.51 years (48.86 years for males and 51.07 years for females), which was 20.14 years lower compared with general population (69.65 years), and the LE gap between patients and general population decreased with age. The largest age-specific mortality contribution to the gap (32.06%) occurred at age 80-84 years. Women had a lower LE and HLE than men at age ≥ 60 years (both gender gaps in LE and HLE < 0). For advanced schistosomiasis patients, the gender gap in LE was largely attributed to the difference in mortality among those under the age of 55; the age-specific mortality in women exerted positive influence on the gap at age 25-64 and 75-79 years, with the contribution rate ranging from 0.59% to 57.02%, and made the negative contribution at other age groups.

CONCLUSIONS

The LE of advanced schistosomiasis patients was still much lower compared with general population. Strengthened prevention strategies and targeted treatments are needed to reduce morbidity and mortality due to advanced schistosomiasis, especially for younger population and elderly female patients.

Development and validation of a prognostic nomogram model for ICU patients with alcohol-associated cirrhosis

BACKGROUND

The prognosis of patients with alcohol-associated cirrhosis (ALC) admitted to the intensive care unit (ICU) is poor. We developed and validated a nomogram (NIALC) for ICU patients with ALC.

METHODS

Predictors of mortality were defined by a machine learning method in a cohort of 394 ICU patients with ALC from the Medical Information Mart for Intensive Care database. Then the nomogram (NIALC) was constructed and evaluated using the AUC. The MELD, MELD-sodium, Child-Pugh, and CLIF-SOFA scores were then compared with NIALC. Two datasets of 394 and 501 ICU patients with ALC were utilized for model validation.

RESULTS

In-hospital mortality was 41% and 21% in the training and external validation sets. Predictors included were blood urea nitrogen, total bilirubin, prothrombin time, serum creatinine, lactate, partial thromboplastin time, phosphate, mean arterial pressure, lymphocytes, fibrinogen, and albumin. The AUCs for the NIALC were 0.767 and 0.760 in the two validation cohorts, which were better than those of the MELD, MELD-sodium, Child-Pugh, and CLIF-SOFA.

CONCLUSION

We developed a nomogram for ICU patients with ALC, which demonstrated better discriminative ability than previous prognostic scores. This nomogram could be conveniently used to facilitate the individualized prediction of death in ICU patients with ALC.

Hepatoprotective Efficacy of Cycloastragenol Alleviated the Progression of Liver Fibrosis in Carbon-Tetrachloride-Treated Mice

The continuous death of hepatocytes induced by various etiologies leads to an aberrant tissue healing process and promotes the progression of liver fibrosis and ultimately chronic liver diseases. To date, effective treatments to delay this harmful process remain an unmet clinical need. Cycloastragenol is an active phytochemical substance isolated from Astragalus membranaceus, a plant used in traditional Chinese medicine to protect the liver. Therefore, our study aimed to elucidate the efficacy of cycloastragenol on carbon-tetrachloride (CCl₄)-induced liver fibrosis in mice. We found that cycloastragenol at 200 mg/kg dosage exhibited anti-fibrotic efficacy as demonstrated by a decrease in collagen deposition, downregulation of mRNA expression of collagen type 1, and a reduction in the content of total collagens. In addition, cycloastragenol further augmented the levels of anti-fibrotic matrix metalloproteinases (Mmps), that is, Mmp8, proMmp9, and Mmp12, which play a pivotal role in fibrosis resolution. According to histological analysis and serum markers of hepatotoxicity, cycloastragenol protected the livers from damage and mitigated the increment of serum alanine aminotransferase and bilirubin implicating hepatoprotective efficacy against CCl₄. Moreover, cycloastragenol upregulated the mRNA expression of interleukin 6, a pleiotropic cytokine plays a vital role in the promotion of hepatocyte regeneration. In conclusion, cycloastragenol alleviated the progression of liver fibrosis in CCl₄-treated mice and its anti-fibrotic efficacy was mainly due to the hepatoprotective efficacy.

A review on the protective effect of active components in Antrodia camphorata against alcoholic liver injury

ETHNOPHARMACOLOGICAL RELEVANCE

Antrodia camphorata is a genus of wood-rot basidiomycete in the family Fomitopsidaceae. It is a valuable medicinal fungus in China that contains more than 78 kinds of active compounds. A. camphorata has good protection effects on the liver, especially on alcoholic liver injury (ALI).

AIM

This paper summarizes the complex occurrence and development of alcoholic liver disease (ALD). In addition, the effect of ALD on the intestine through the gut-liver axis is summarized. The protective mechanism of A. camphorata on ALI is reviewed to reveal its therapeutic potential, offering insights into future research.

MATERIALS AND METHODS

A comprehensive search in the literature was obtained from books and online databases such as Web of Science, Google Scholar, PubMed, Scopus, Science direct, ACS Publications and Baidu Scholar.

RESULTS

The pathogenesis of ALD mainly includes oxidative stress injury, intestinal microflora imbalance, inflammatory mediator injury and nutritional imbalance. A. camphorata contains rich active components (e.g. polysaccharides, triterpenoids, maleic and succinic acid derivatives, amino acids, superoxide dismutase, vitamins, lignin and sterols). These components have good antioxidant, anti-inflammatory and intestinal protection activities. Therefore, A. camphorata has a wide application in the prevention and treatment of ALI.

CONCLUSIONS

ALD develops from a mild disease to alcoholic hepatitis and cirrhosis, which is the main reason of global morbidity and mortality. At present, there is no effective drug for the treatment of ALD. A. camphorata, as a valuable medicinal fungus unique to Taiwan, has a great protective effect on the liver. It is expected to be an effective drug for ALI treatment. Although many studies have performed the protective effects of A. camphorata on ALI, its regulatory effects on the gut-liver axis of ALD patients need to be further explored.

Pharmacological modulation of ferroptosis as a therapeutic target for liver fibrosis

Liver fibrosis, which is characterized by the excessive deposition of extracellular matrix (ECM) materials (primarily fibrillar collagen-I), is an abnormal repair reaction and pathological outcome of chronic liver diseases caused by alcohol abuse, non-alcoholic fatty liver disease, and chronic hepatitis B and C virus infections. Liver fibrosis often progresses to liver cirrhosis and hepatocellular carcinoma. Ferroptosis, characterized by lipid peroxidation, is a form of iron-dependent non-apoptotic cell death, and recent studies have reported that ferroptosis contribute to the development of liver fibrosis. Moreover, several agents have demonstrated therapeutic effects in experimental liver fibrosis models by inducing hepatic stellate cell (HSCs) ferroptosis. This review delineates the specific mechanism by which ferroptosis contributes to the development of liver fibrosis. Specifically, we focused on the different types of therapeutic agents that can induce HSCs ferroptosis and summarize their pharmacological effectiveness for liver fibrosis treatment. We suggest that HSCs ferroptosis may be a potential useful target of novel therapies for preventing and treating liver fibrosis.