Pathogenesis of Alcohol-Associated Liver Disease

Immunological mechanisms and emerging therapeutic targets in alcohol-associated liver disease

Alcohol-associated liver disease (ALD) is a major global health challenge, with inflammation playing a central role in its progression. As inflammation emerges as a critical therapeutic target, ongoing research aims to unravel its underlying mechanisms. This review explores the immunological pathways of ALD, highlighting the roles of immune cells and their inflammatory mediators in disease onset and progression. We also examine the complex interactions between inflammatory cells and non-parenchymal liver cells, as well as their crosstalk with extra-hepatic organs, including the gut, adipose tissue, and nervous system. Furthermore, we summarize current clinical research on anti-inflammatory therapies and discuss promising therapeutic targets. Given the heterogeneity of ALD-associated inflammation, we emphasize the need for precision medicine to optimize treatment strategies and improve patient outcomes.

Chronic alcohol intake disrupts cytochrome P450 enzyme activity in alcoholic fatty liver disease: insights into metabolic alterations and therapeutic targets

Introduction

Alcoholic fatty liver disease (AFLD) is a common consequence of chronic alcohol consumption, characterized by lipid accumulation and oxidative stress in the liver. Cytochrome P450 (CYP450) enzymes play essential roles in metabolizing alcohol and other compounds. However, the specific long-term effects of alcohol on these enzymes remain unclear.

Methods

This study the examines influence of prolonged ethanol exposure on CYP450 activity and expression in AFLD using a rat model. Key enzymes such as CYP2E1, CYP2D6, and CYP3A1 were assessed in relation to lipid accumulation and oxidative stress.

Results

Significant alterations were identified in the expression and activity of CYP2E1, CYP2D6, and CYP3A1, which were associated with increased lipid accumulation and oxidative stress in the liver. Additionally, the expression of P-glycoprotein (P-gp) was elevated, suggesting that chronic alcohol intake may impact drug transport and excretion.

Discussion

These findings provide new insights into the molecular mechanisms of AFLD and highlight the potential of CYP450 modulation as a therapeutic target. By elucidating how long-term ethanol exposure disrupts hepatic CYP450 enzyme profiles, this research lays the groundwork for developing personalized therapeutic strategies to improve outcomes for patients with AFLD.

Phytochemicals Targeting Inflammatory Pathways in Alcohol-Induced Liver Disease: A Mechanistic Review

Alcoholic beverages play a significant role in social engagement worldwide. Excessive alcohol causes a variety of health complications. Alcohol-induced liver disease (ALD) is responsible for the bulk of linked fatalities. The activation of immune mechanisms has a crucial role in developing ALD. No effective medication promotes liver function, shields the liver from harm, or aids in hepatic cell regeneration. Alcohol withdrawal is one of the most beneficial therapies for ALD patients, which improves the patient's chances of survival. There is a crucial demand for safe and reasonably priced approaches to treating it. Exploring naturally derived phytochemicals has been a fascinating path, and it has drawn attention in recent years to modulators of inflammatory pathways for the prevention and management of ALD. In this review, we have discussed the roles of various immune mechanisms in ALD, highlighting the importance of intestinal barrier integrity and gut microbiota, as well as the roles of immune cells and hepatic inflammation, and other pathways, including cGAS-STING, NLRP3, MAPK, JAK-STAT, and NF-kB. Further, this review also outlines the possible role of phytochemicals in targeting these inflammatory pathways to safeguard the liver from alcohol-induced injury. We highlighted that targeting immunological mechanisms using phytochemicals or herbal medicine may find a place to counteract ALD. Preclinical in vitro and in vivo investigations have shown promising results; nonetheless, more extensive work is required to properly understand these compounds' mechanisms of action. Clinical investigations are very crucial in transferring laboratory knowledge into effective patient therapy.

Epigenetic therapy for alcoholic hepatitis: can larsucosterol change the treatment landscape?

Alcohol-induced liver disease, encompassing steatosis, hepatitis, cirrhosis, and liver failure, is a significant global health burden, affecting 10-35% of individuals with alcohol use disorder. Alcoholic hepatitis, characterized by hepatocyte inflammation due to chronic alcohol consumption, arises from toxic intermediates produced during alcohol metabolism. These intermediates disrupt cellular function, trigger immune responses, and promote fibrosis, leading to cirrhosis and liver failure. Despite current treatments like corticosteroids and liver transplantation, which alleviate symptoms but fail to reverse cellular damage, the rising prevalence of alcoholic hepatitis underscores the urgent need for innovative therapies. Larsucosterol, a novel epigenetic modulator, has emerged as a promising candidate. By inhibiting DNA methyltransferase, larsucosterol reduces DNA hypermethylation and modulates genes involved in inflammation, lipid metabolism, and cell survival, thereby mitigating liver damage. Early-phase clinical trials, including a phase 2a study, demonstrated its safety, tolerability, and improved biochemical parameters in patients. However, the phase 2b AHFIRM trial did not achieve its primary endpoint, though a lower mortality rate in the 30 mg group suggests potential benefits requiring further investigation. Larsucosterol's immunomodulatory and anti-inflammatory properties offer advantages over corticosteroids, particularly in patients unresponsive to standard therapies. Despite its promise, limitations such as the need for larger, more diverse trials, long-term safety data, and exploration of combination therapies remain. In conclusion, larsucosterol represents a groundbreaking approach to treating alcoholic hepatitis, but extensive research is essential to fully establish its therapeutic potential and address existing gaps in knowledge.

Enhanced bioactivity of honeysuckle-Cassia seeds extracts through Lactobacillus acidophilus and Bacillus subtilis co-fermentation: Impact on alcoholic liver disease and gut microbiota

This study investigated the hepatoprotective potential of Honeysuckle-Cassia seeds extracts co-fermented with Lactobacillus acidophilus and Bacillus subtilis against alcoholic liver disease (ALD) and gut microbiota dysbiosis. Through network pharmacology analysis, 209 overlapping targets between Honeysuckle-Cassia seeds bioactive components and ALD-related targets were identified, with 39 core targets subsequently determined. Comparative analysis of aqueous extract (AE), Lactobacillus acidophilus fermentation broth (LAF), and mixed bacteria fermentation broth (MBF) revealed that MBF significantly enhanced the content of bioactive compounds: total polysaccharides (72.6 ± 3.8 mg/g), flavonoids (34.7 ± 2.5 mg/g), and saponins (15.2 ± 1.1 mg/g), representing 275 %, 72 %, and 62 % increases over AE, respectively (p < 0.05). In a murine ALD model, MBF intervention (12.5 mL/kg, 30 days) significantly reduced serum markers of liver injury (ALT: 35 %, AST: 28 %, TC: 42 %, TG: 39 %; (p < 0.05) and hepatic oxidative stress (MDA ↓52 %, GSH ↑156.55 %, SOD ↑76.71 %). Mechanistically, MBF suppressed pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) by 40-50 % while elevating anti-inflammatory mediators (IL-4, IL-10, PGE2) 1.6-2.0-fold via AMPK/ACC/SREBP1c signaling modulation. Gut microbiota analysis revealed that MBF restored α-diversity indices (Shannon ↑10.06 %, ACE ↑32.34 %) and reversed alcohol-induced dysbiosis by enriching Lachnospiraceae and Blautia while suppressing Alloprevotella. Structural degradation of plant residues (SEM) confirmed microbial synergy in releasing insoluble-bound phytochemicals (100-400 m/z range). These findings validate co-fermentation as a potent strategy to amplify the hepatoprotective and microbiota-modulating activities of traditional herbs, offering a scientific foundation for developing functional foods against ALD.

G0S2 Promotes PD-L1 Expression in Monocytes and Influences the Efficacy of PD-1 Inhibitors in Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) is a prevalent and highly lethal form of liver cancer, with limited effective treatment options, particularly in the advanced stages. Immunotherapy using PD-1 inhibitors has emerged as a promising treatment modality, yet a substantial proportion of patients exhibit resistance or fail to respond to such therapies. This study aimed to elucidate the role of G0/G1 Switch 2 (G0S2) in regulating PD-L1 expression in monocytes within the HCC tumor microenvironment and to investigate its impact on the efficacy of PD-1 inhibitors. Methods: Gene expression data among HCC patients treated with PD-1 inhibitors were obtained from the HCC single-cell sequencing database; immunohistochemistry was performed to detect G0S2 expression in liver cancer tissues and adjacent non-tumorous tissues of HCC patients; flow cytometry was utilized to analyze the expression of G0S2, PD-L1, CD206, and CD14 in PBMCs from HCC patients; and CD8+T cell proliferation and IFN-γ secretion were used to evaluate the impact of G0S2 knockdown. Results: Utilizing single-cell sequencing data from HCC patients, we identified that G0S2 expression was significantly elevated in the non-responders (NR) compared to responders (R) to PD-1 inhibitor therapy. The immunohistochemical analysis confirmed higher levels of G0S2 in HCC tumor tissues and adjacent non-tumorous tissues, while the flow cytometry revealed the increased expression of G0S2, PD-L1, and CD206 in peripheral blood mononuclear cells (PBMCs) from NR patients compared to R patients and healthy controls. The functional experiments involving the knockdown of G0S2 in the THP-1 monocyte cell line resulted in a significant reduction in PD-L1 expression and a concomitant increase in CD8+T cell proliferation and IFN-γ production. Conclusions: These findings indicate that G0S2 facilitates the upregulation of PD-L1 in monocytes, thereby suppressing T cell activity and contributing to resistance against PD-1 inhibitors in HCC. The high expression of G0S2 in peripheral blood monocytes offers a non-invasive and easily detectable biomarker for predicting the efficacy of PD-1 inhibitor therapy. Consequently, targeting G0S2 may enhance the responsiveness to immunotherapy in HCC patients, providing a new avenue for optimizing treatment strategies and improving patient outcomes.

Suppressor of cytokine signaling 2 modulates regulatory T cell activity to suppress liver hepatocellular carcinoma growth and metastasis

BACKGROUND

Liver hepatocellular carcinoma (LIHC) is a highly aggressive cancer with poor prognosis due to its complex tumor microenvironment (TME) and immune evasion. Regulatory T cells (Tregs) play a critical role in tumor progression. Suppressor of cytokine signaling 2 (SOCS2), a key immune regulator, may modulate Treg activity and impact LIHC growth and metastasis.

AIM

To explore how the SOCS2 affects Treg activity in LIHC and its impact on tumor growth and metastasis.

METHODS

LIHC transcriptome data from The Cancer Genome Atlas database were analyzed using Gene Set Enrichment Analysis, Estimation of Stromal and Immune Cells in Malignant Tumors Using Expression Data, and Cell-Type Identification by Estimating Relative Subsets of RNA Transcripts to evaluate immune pathways and Treg infiltration. Key prognostic genes were identified using Weighted Gene Co-expression Network Analysis and machine learning. In vitro, co-culture experiments, migration assays, apoptosis detection, and enzyme-linked immunosorbent assay were conducted. In vivo, tumor growth, metastasis, and apoptosis were assessed using subcutaneous and lung metastasis mouse models with hematoxylin and eosin staining, Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling, and immunohistochemistry analyses.

RESULTS

SOCS2 overexpression inhibited Treg cell activity, reducing LIHC cell migration and invasion while increasing apoptosis. In vivo, SOCS2 suppressed tumor growth and metastasis, confirming its therapeutic potential.

CONCLUSION

SOCS2 modulates CD4+ T function in the TME, contributing to LIHC progression. Targeting SOCS2 presents a potential therapeutic strategy for treating LIHC.

The protective effects and mechanism of myricetin in liver diseases (Review)

Liver diseases have become one of the significant threats to global health. However, there is a lack of effective targeted therapeutic drugs in this field and the existing drugs used for liver disease treatment usually have side‑effects. Traditional Chinese medicine (TCM) has the distinctive advantages of multi‑target and low side‑effects. As a flavonoid with various pharmacological activities such as anti‑tumour, anti‑oxidant, anti‑inflammatory and anti‑bacterial, the TCM myricetin has been widely used in liver disease research. The present work focuses on the role and molecular mechanism of myricetin in liver diseases such as acute liver injury, fatty liver, liver fibrosis and hepatocellular carcinoma. It is a promising reference for further research and application of myricetin in the treatment of liver diseases.

Amelioration of Alcoholic Hepatic Steatosis in a Rat Model via Consumption of Poly-γ-Glutamic Acid-Enriched Fermented Protaetia brevitarsis Larvae Using Bacillus subtilis

Alcoholic hepatic steatosis (AHS) is a common early-stage symptom of liver disease caused by alcohol consumption. Accordingly, several aspects of AHS have been studied as potential preventive and therapeutic targets. In this study, a novel strategy was employed to inhibit fatty liver accumulation and counteract AHS through the consumption of microorganism-fermented Protaetia brevitarsis larvae (FPBs). By using an AHS rat model, we assessed the efficacy of FPB by examining the lipid profile of liver/serum and liver function tests to evaluate lipid metabolism modulation. After FPB administration, the lipid profile-including high-density lipoprotein, total cholesterol, and total triglycerides-and histopathological characteristics exhibited improvement in the animal model. Interestingly, AHS amelioration via FPBs administration was potentially associated with poly-γ-glutamic acid (PγG), which is produced by Bacillus species during fermentation. These findings support the formulation of novel natural remedies for AHS through non-clinical animal studies, suggesting that PγG-enriched FPBs are a potentially valuable ingredient for functional foods, providing an ameliorative effect on AHS.

Ginsenoside Rg1: A bioactive therapeutic agent for diverse liver diseases

Diverse liver diseases are characterised by late diagnosis and rapid progression and have become one of the major threats to human health. To delay the transition from benign tissue lesions to a substantial organ injury, scientists have gradually applied natural compounds derived from plants as a complementary therapy in the field of hepatology. Ginseng (Panax ginseng C. A. Meyer) is a tonic traditional Chinese herbal medicine, and natural products, including ginsenoside Rg1 (G-Rg1), which is a kind of 20(S)-protopanaxatriol saponin with a relatively high biological activity, can be isolated from the roots or stems of ginseng. Given these information, this review aimed to summarise and discuss the metabolic mechanisms of G-Rg1 in the regulation of diverse liver diseases and the measures to improve its bioavailability. As a kind of monomer in Chinese medicine with multitarget pharmacological effects, G-Rg1 can provide significant therapeutic benefits in the alleviation of alcoholic liver disease, nonalcoholic fatty liver disease, liver fibrosis, viral hepatitis, etc., which mainly rely on the inhibition of apoptosis, strengthening endogenous anti-inflammatory and antioxidant mechanisms, activation of immune responses and regulation of efflux transport signals, to improve pathological changes in the liver caused by lipid deposition, inflammation, oxidative stress, accumulation of hepatotoxic product, etc. However, the poor bioavailability of G-Rg1 must be overcome to improve its clinical application value. In summary, focusing on the hepatoprotective benefits of G-Rg1 will provide new insights into the development of natural Chinese medicine resources and their pharmaceutical products to target the treatment of liver diseases.

Genetic associations between orexin genes and phenotypes related to behavioral regulation in humans, including substance use

The hypothalamic neuropeptide system of orexin (hypocretin) neurons provides projections throughout the neuraxis and has been linked to sleep regulation, feeding and motivation for salient rewards including drugs of abuse. However, relatively little has been done to examine genes associated with orexin signaling and specific behavioral phenotypes in humans. Here, we tested for association of twenty-seven genes involved in orexin signaling with behavioral phenotypes in humans. We tested the full gene set, functional subsets, and individual genes involved in orexin signaling. Our primary phenotype of interest was Externalizing, a composite factor comprised of behaviors and disorders associated with reward-seeking, motivation, and behavioral regulation. We also tested for association with additional phenotypes that have been related to orexin regulation in model organism studies, including alcohol consumption, problematic alcohol use, daytime sleepiness, insomnia, cigarettes per day, smoking initiation, and body mass index. The composite set of 27 genes corresponding to orexin function was highly associated with Externalizing, as well as with alcohol consumption, insomnia, cigarettes per day, smoking initiation and BMI. In addition, all gene subsets (except the OXR2/HCRTR2 subset) were associated with Externalizing. BMI was significantly associated with all gene subsets. The "validated factors for PPOX/HCRT" and "PPOX/HCRT upregulation" gene subsets also were associated with alcohol consumption. Individually, 8 genes showed a strong association with Externalizing, 12 with BMI, 7 with smoking initiation, 3 with alcohol consumption, and 2 with problematic alcohol use, after correction for multiple testing. This study indicates that orexin genes are associated with multiple behaviors and disorders related to self-regulation in humans. This is consistent with prior work in animals that implicated orexin signaling in motivational activation induced by salient stimuli, and supports the hypothesis that orexin signaling is an important potential therapeutic target for numerous behavioral disorders.

Transitioning from NAFLD to MAFLD and MASLD: the toxic relationship with alcohol consumption

Alcohol is a well-known toxic etiologic factor for liver injury. Metabolic substrates of alcohol (especially acetaldehyde) have a major responsibility and genetic susceptibility, alterations in microbiota and immune system are important co-factors for this injury. Major injury in liver is hepatocellular lipid accumulation. Therefore the relationship between non-alcoholic and alcoholic fatty liver diseases should have been defined clearly. Recently two major liver committees adopted new terminologies such as metabolic-associated fatty liver disease (MAFLD), metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related liver disease (MetALD), and alcoholic liver disease (ALD) instead of non-alcoholic fatty liver disease (NAFLD). These terminologies were based on the effects of metabolic syndrome on liver. Alcohol consumption was defined differently according to these nomenclatures. MAFLD defined alcohol intake (regardless of amount) as “dual etiology fatty liver disease” and the Delphi consensus defined MASLD, MetALD, or ALD according to daily consumption of alcohol amount.

Etiology-Dependent Microbiome Differences in Hepatocellular Carcinoma Development

Chronic liver disease is characterised by persistent inflammation, tissue damage, and regeneration, which leads to steatosis, fibrosis, and, lastly, cirrhosis and hepatocellular carcinoma (HCC). HCC, the most prevalent form of primary liver cancer, is one of the leading causes of cancer-related mortality worldwide. The gut microbiota plays a fundamental role in human physiology, and disturbances in its critical balance are widely recognised as contributors to various pathological conditions, including chronic liver diseases, both infectious and non-infectious in nature. Growing interest in microbiota research has recently shifted the focus towards the study of intratumoural microbiota, referred to as the "oncobiome", which can significantly impact the development and progression of HCC. In this review, we discuss existing research and provide an overview of the microbiota influence on viral hepatitis, particularly in shaping the progression of liver disease caused by the hepatitis B and hepatitis C viruses. We also explore microbial dysbiosis and its contribution to the silent and dangerous progression of non-alcoholic fatty liver disease. Additionally, we address the impact of alcohol on the liver and its interaction with the microbiota, tracing the pathway from inflammation to cirrhosis and cancer. The review emphasises the most common etiologies of hepatocellular carcinoma.

RSK1 and RSK2 as therapeutic targets: an up-to-date snapshot of emerging data

INTRODUCTION

The four members of the p90 ribosomal S6 kinase (RSK) family are serine/threonine protein kinases, which are phosphorylated and activated by ERK1/2. RSK1/2/3 are further phosphorylated by PDK1. Receiving inputs from two major signaling pathways places RSK as a key signaling node in numerous pathologies. A plethora of RSK1/2 substrates have been identified, and in the majority of cases the causative roles these RSK substrates play in the pathology are unknown.

AREAS COVERED

The majority of studies have focused on RSK1/2 and their functions in a diverse group of cancers. However, RSK1/2 are known to have important functions in cardiovascular disease and neurobiological disorders. Based on the literature, we identified substrates that are common in these pathologies with the goal of identifying fundamental physiological responses to RSK1/2.

EXPERT OPINION

The core group of targets in pathologies driven by RSK1/2 are associated with the immune response. However, there is a paucity of the literature addressing RSK function in inflammation, which is critical to know as the pan RSK inhibitor, PMD-026, is entering phase II clinical trials for metastatic breast cancer. A RSK inhibitor has the potential to be used in numerous diverse diseases and disorders.

Gut-liver axis: Recent concepts in pathophysiology in alcohol-associated liver disease

The growing recognition of the role of the gut microbiome's impact on alcohol-associated diseases, especially in alcohol-associated liver disease, emphasizes the need to understand molecular mechanisms involved in governing organ-organ communication to identify novel avenues to combat alcohol-associated diseases. The gut-liver axis refers to the bidirectional communication and interaction between the gut and the liver. Intestinal microbiota plays a pivotal role in maintaining homeostasis within the gut-liver axis, and this axis plays a significant role in alcohol-associated liver disease. The intricate communication between intestine and liver involves communication between multiple cellular components in each organ that enable them to carry out their physiological functions. In this review, we focus on novel approaches to understanding how chronic alcohol exposure impacts the microbiome and individual cells within the liver and intestine, as well as the impact of ethanol on the molecular machinery required for intraorgan and interorgan communication.

Osteopontin: an indispensable component in common liver, pancreatic, and biliary related disease

BACKGROUND

The liver, gallbladder, and pancreas constitute a critically important system of digestive and endocrine organs in the human body, performing essential and complex physiological functions. At present, diseases of this digestive system have a high incidence in the world and is a more common disease. However, osteopontin (OPN) plays a crucial role in common liver, pancreatic, and biliary diseases, and its mechanisms of action merit further exploration and study.

METHODS

We performed an analysis to assess the role of osteopontin in liver, pancreatic, and biliary diseases, focusing on its significance in these conditions.

RESULTS

Osteopontin, a profoundly phosphorylated glycoprotein, can be utilized as a diagnostic marker for hepatocellular carcinoma and cholangiopathies. Additionally it assists in the treatment of non-alcoholic fatty liver disease and promotes the proliferation, migration, and invasion of pancreatic cancer cells. Furthermore, osteopontin regulates inflammatory responses in chronic pancreatitis.

CONCLUSIONS

This review offers a thorough analysis of the genetic and protein architecture of OPN, and elucidates the relationship between osteopontin and liver, pancreatic, and biliary diseases. Furthermore, exclusive focus is lavished on the potential utility of OPN as a biomarker and an innovative therapeutic target in the management of these disorder.

Therapeutic effects of fecal microbial transplantation on alcoholic liver injury in rat models

OBJECTIVE

Disruption of gut microbiota is closely related to the progression of alcoholic liver disease (ALD). This study aimed to explore the therapeutic effect of fecal microbiota transplantation (FMT) in ALD rats using a combination of microbiological and metabolomic techniques.

METHODS

Three liver injury rat models were constructed using alcohol, CCL4, and alcohol combined with CCL4, and administered an FMT treatment comprising the fecal microbiota of healthy rats via the gastric route for 12 consecutive weeks. We measured the therapeutic effect of FMT treatment on liver inflammation, intestinal mucosal barrier, and bacterial translocation in ALD rats using 16S rRNA and UPLC-Q/TOF-MS technology to detect the effects of FMT on the intestinal microbiota and metabolic patterns of ALD rats.

RESULTS

FMT treatment effectively improved liver function, prolonged survival time, improved the intestinal mucosal barrier, reduced bacterial translocation, alleviated liver inflammation, and delayed the progression of liver fibrosis in three types of liver injury models. The microbiome and metabolomic results showed that FMT can effectively improve gut microbiota disorder in ALD rats and improve metabolic patterns by regulating metabolic pathways such as the arachidonic acid and retinol pathways.

CONCLUSION

FMT treatment could reverse alcohol induced liver injury by improving gut microbiota and metabolic patterns in ALD rats, and oral FMT could be an effective therapeutic approach for ALD.

Oxidative stress in alcoholic liver disease, focusing on proteins, nucleic acids, and lipids: A review

Oxidative stress is one of the important factors in the development of alcoholic liver disease. The production of reactive oxygen species and other free radicals is an important feature of alcohol metabolism in the liver and an important substance in liver injury. When large amounts of ROS are produced, the homeostasis of the liver REDOX system will be disrupted and liver injury will be caused. Oxidative stress can damage proteins, nucleic acids and lipids, liver dysfunction. In addition, damaging factors produced by oxidative damage to liver tissue can induce the occurrence of inflammation, thereby aggravating the development of ALD. This article reviews the oxidative damage of alcohol on liver proteins, nucleic acids, and lipids, and provides new insights and summaries of the oxidative stress process. We also discussed the relationship between oxidative stress and inflammation in alcoholic liver disease from different perspectives. Finally, the research status of antioxidant therapy in alcoholic liver disease was summarized, hoping to provide better help for learning and developing the understanding of alcoholic liver disease.

Expansion of effector regulatory T cells in steroid responders of severe alcohol-associated hepatitis

While steroid therapy is the preferred treatment for severe alcohol-associated hepatitis, the role of effector regulatory T (eTreg) cells and their association with steroid response and clinical outcomes in these patients remains to be elucidated. We prospectively enrolled 47 consecutive patients with alcohol-associated hepatitis, consisting of severe alcohol-associated hepatitis treated with steroids (n=18; steroid-treated group) and mild alcohol-associated hepatitis (n=29; nontreated group). After isolating peripheral blood mononuclear cells from the patients at enrollment and again 7 days later, the frequency of eTreg cells was examined using flow cytometry. Single-cell RNA sequencing analysis was conducted using paired peripheral blood mononuclear cells. In vitro experiments were also performed to assess phenotype changes and the suppressive function of Treg cells following steroid treatment. The steroid-treated group exhibited significantly higher Model for End-Stage Liver Disease scores than the nontreated group ( p < 0.01). Within the steroid-treated group, the proportion of eTreg cells significantly expanded in the steroid responders (n=13; p = 0.01). Furthermore, a significant positive correlation was observed between the decrease in the Model for End-Stage Liver Disease score and the increase in eTreg cells ( p < 0.05). Single-cell RNA sequencing using paired peripheral blood mononuclear cells (pre-steroid and post-steroid therapy) from a steroid responder revealed gene expression changes in T cells and monocytes, suggesting enhancement of Treg cell function. In vitro results showed an elevation in the proportion of eTreg cells after steroid therapy. In conclusion, our findings suggest that the efficacy of steroid therapy in patients with severe alcohol-associated hepatitis is mediated by an increase in the number of eTreg cells.

Alcohol- and Low-Iron Induced Changes in Antioxidant and Energy Metabolism Associated with Protein Lys Acetylation

Understanding the role of iron in ethanol-derived hepatic stress could help elucidate the efficacy of dietary or clinical interventions designed to minimize liver damage from chronic alcohol consumption. We hypothesized that normal levels of iron are involved in ethanol-derived liver damage and reduced dietary iron intake would lower the damage caused by ethanol. We used a pair-fed mouse model utilizing basal Lieber-DeCarli liquid diets for 22 weeks to test this hypothesis. In our mouse model, chronic ethanol exposure led to mild hepatic stress possibly characteristic of early-stage alcoholic liver disease, seen as increases in liver-to-body weight ratios. Dietary iron restriction caused a slight decrease in non-heme iron and ferritin (FeRL) expression while it increased transferrin receptor 1 (TfR1) expression without changing ferroportin 1 (FPN1) expression. It also elevated protein lysine acetylation to a more significant level than in ethanol-fed mice under normal dietary iron conditions. Interestingly, iron restriction led to an additional reduction in nicotinamide adenine dinucleotide (NAD+) and NADH levels. Consistent with this observation, the major mitochondrial NAD+-dependent deacetylase, NAD-dependent deacetylase sirtuin-3 (SIRT3), expression was significantly reduced causing increased protein lysine acetylation in ethanol-fed mice at normal and low-iron conditions. In addition, the detection of superoxide dismutase 1 and 2 levels (SOD1 and SOD2) and oxidative phosphorylation (OXPHOS) complex activities allowed us to evaluate the changes in antioxidant and energy metabolism regulated by ethanol consumption at normal and low-iron conditions. We observed that the ethanol-fed mice had mild liver damage associated with reduced energy and antioxidant metabolism. On the other hand, iron restriction may exacerbate certain activities of ethanol further, such as increased protein lysine acetylation and reduced antioxidant metabolism. This metabolic change may prove a barrier to the effectiveness of dietary reduction of iron intake as a preventative measure in chronic alcohol consumption.

NLRP3 Inflammasome in Acute and Chronic Liver Diseases

NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) is an intracellular complex that upon external stimuli or contact with specific ligands, recruits other components, forming the NLRP3 inflammasome. The NLRP3 inflammasome mainly mediates pyroptosis, a highly inflammatory mode of regulated cell death, as well as IL-18 and IL-1β production. Acute and chronic liver diseases are characterized by a massive influx of pro-inflammatory stimuli enriched in reactive oxygen species (ROS) and damage-associated molecular patterns (DAMPs) that promote the assemblage and activation of the NLRP3 inflammasome. As the major cause of inflammatory cytokine storm, the NLRP3 inflammasome exacerbates liver diseases, even though it might exert protective effects in regards to hepatitis C and B virus infection (HCV and HBV). Here, we summarize the current knowledge concerning NLRP3 inflammasome function in both acute and chronic liver disease and in the post liver transplant setting, focusing on the molecular mechanisms involved in NLRP3 activity.

A Review: Cytochrome P450 in Alcoholic and Non-Alcoholic Fatty Liver Disease

Alcoholic fatty liver disease (FALD) and non-alcoholic fatty liver disease (NAFLD) have similar pathological spectra, both of which are associated with a series of symptoms, including steatosis, inflammation, and fibrosis. These clinical manifestations are caused by hepatic lipid synthesis and metabolism dysregulation and affect human health. Despite having been studied extensively, targeted therapies remain elusive. The Cytochrome P450 (CYP450) family is the most important drug-metabolising enzyme in the body, primarily in the liver. It is responsible for the metabolism of endogenous and exogenous compounds, completing biological transformation. This process is relevant to the occurrence and development of AFLD and NAFLD. In this review, the correlation between CYP450 and liver lipid metabolic diseases is summarised, providing new insights for the treatment of AFLD and NAFLD.

Regulation Mechanism and Potential Value of Active Substances in Spices in Alcohol-Liver-Intestine Axis Health

Excessive alcohol intake will aggravate the health risk between the liver and intestine and affect the multi-directional information exchange of metabolites between host cells and microbial communities. Because of the side effects of clinical drugs, people tend to explore the intervention value of natural drugs on diseases. As a flavor substance, spices have been proven to have medicinal value, but they are still rare in treating hepatointestinal diseases caused by alcohol. This paper summarized the metabolic transformation of alcohol in the liver and intestine and summarized the potential value of various perfume active substances in improving liver and intestine diseases caused by alcohol. It is also found that bioactive substances in spices can exert antioxidant activity in the liver and intestine environment and reduce the oxidative stress caused by diseases. These substances can interfere with fatty acid synthesis, promote sugar and lipid metabolism, and reduce liver injury caused by steatosis. They can effectively regulate the balance of intestinal flora, promote the production of SCFAs, and restore the intestinal microenvironment.

In vitro digestibility and hepato-protective potential of Lophatherum gracile Brongn. leave extract

Lophatherum gracile Brongn. (L. gracile) is a traditional herb for both medicine and food use, but its digestibility and hepato-protective activity is unknown. Herein we investigated the digestibility and hepato-protective potential of L. gracile leave extract (LGE) using in vitro digestion and alcohol-induced oxidative damage models. Compared to the undigested group, the content of phenolics/flavonoids and the antioxidant activity in LGE generally decreased by 9.30-19.97% in the oral and small intestine phase after digestion, while that increased by 9.96-10.17% in the gastric phase. The main phenolics/flavonoids showed promising stability during digestion and their bio-accessiblity ranged from 67.64% to 84.47%. By reducing cellular reactive oxidative species and malonaldehyde levels, LGE (0.23-0.45 mg/mL) pretreatment significantly ameliorated alcohol-induced oxidative damage in HepG2 cells (P < 0.05), and their survival rate increased from 59.23% to 67.76%. These findings suggested that L. gracile could be used for the development of hepato-protective foods.

Hepatocyte-specific mitogen-activated protein kinase phosphatase 1 in sexual dimorphism and susceptibility to alcohol induced liver injury

Background

It is well established that females are more susceptible to the toxic effects of alcohol, although the exact mechanisms are still poorly understood. Previous studies noted that alcohol reduces the expression of mitogen-activated protein kinase phosphatase 1 (MKP1), a negative regulator of mitogen-activated protein kinases (MAPK) in the liver. However, the role of hepatocyte- specific MKP1 in the pathogenesis of alcohol-associated liver disease (ALD) remains uncharacterized. This study aimed to evaluate the role of hepatocyte-specific MKP1 in the susceptibility and sexual dimorphism in alcohol-induced liver injury.

Methods

C57Bl/6 mice were used in an intragastric ethanol feeding model of alcohol-associated steatohepatitis (ASH). Hepatocyte-specific Mkp1-/- knockout and (Mkp1+/+ "f/f" male and female mice were subjected to the NIAAA chronic plus binge model. Primary mouse hepatocytes were used for in vitro studies. Liver RNA sequencing was performed on an Illumina NextSeq 500. Liver injury was evaluated by plasma alanine transaminase (ALT), hepatic ER stress and inflammation markers. Statistical analysis was carried out using ANOVA and the unpaired Student's t-test.

Results

ASH was associated with the severe injury accompanied by increased endoplasmic reticulum (ER) stress and significant downregulation of Dusp1 mRNA expression. In vitro, ethanol treatment resulted in a time-dependent decrease in Dusp1 mRNA and protein expression in primary hepatocytes in both males and females; however, this effect was significantly more pronounced in hepatocytes from females. In vivo, female mice developed more liver injury in a chronic plus binge model which was accompanied by a significant decrease in liver Dusp1 mRNA expression. In comparison, liver Dusp1 was not changed in male mice, while they developed milder injury to alcohol. Mkp1 deletion in hepatocytes led to increased alcohol induced liver injury, ER stress and inflammation in both sexes.

Conclusion

Hepatocyte Mkp1 plays a significant role in alcohol induced liver injury. Alcohol downregulates Mkp1 expression in hepatocytes in a sex dependent manner and could play a role in sexual dimorphism in increased female susceptibility to alcohol.

Recent Progresses on Pathophysiology, Diagnosis, Therapeutic Modalities, and Management of Non-alcoholic Fatty Liver Disorder

Abstract:

Non-alcoholic fatty liver disease (NAFLD) is currently the utmost common chronic liver disorder that happens through all age groups and is identified to occur in 14%-30% of the general population, demonstrating a critical and grossing clinical issue because of the growing incidence of obesity and overweight. From the histological aspect, it looks like alcoholic liver damage, but it happens in patients who avoid remarkable alcohol usage. NAFLD comprises a broad spectrum, ranging from benign hepatocellular steatosis to inflammatory nonalcoholic steatohepatitis (NASH), different levels of fibrosis, and cirrhosis. Patients with NASH are more susceptible to more rapid progression to cirrhosis and hepatocellular carcinoma. There is no single factor that drives proceeding from simple steatosis to NASH. However, a combination of multi parameters such as genetic background, gut microflora, intake of high fat/ fructose dietary contents or methionine/choline-deficient diet, and consequently accumulated hepatocellular lipids mainly including triglycerides and also other bio-analytes, such as free fatty acids, cholesterol, and phospholipids display a crucial role in disease promotion. NAFLD is related to overweight and insulin resistance (IR) and is regarded as the hepatic presentation of the metabolic syndrome, an amalgamation of medical statuses such as hyperlipidemia, hypertension, type 2 diabetes, and visceral obesity. Despite the increasing prevalence of this disease, which imposes a remarkable clinical burden, most affected patients remain undiagnosed in a timely manner, largely related to the asymptomatic entity of NAFLD patients and the unavailability of accurate and efficient noninvasive diagnostic tests. However, liver biopsy is considered a gold standard for NAFLD diagnosis, but due to being expensive and invasiveness is inappropriate for periodic disease screening. Some noninvasive monitoring approaches have been established recently for NAFLD assessment. In addition to the problem of correct disease course prediction, no effective therapeutic modalities are approved for disease treatment. Imaging techniques can commonly validate the screening and discrimination of NAFLD; nevertheless, staging the disease needs a liver biopsy. The present therapeutic approaches depend on weight loss, sports activities, and dietary modifications, although different insulin-sensitizing drugs, antioxidants, and therapeutic agents seem hopeful. This review aims to focus on the current knowledge concerning epidemiology, pathogenesis, and different biochemical experiments and imaging modalities applied to diagnose the different grades of NAFLD and its management, as well as new data about pharmacological therapies for this disorder.

FIB-4 index is associated with mortality in critically ill patients with alcohol use disorder: Analysis from the MIMIC-IV database

BACKGROUND

The relationship between fibrosis-4 (FIB-4) index and all-cause mortality in critically ill patients with alcohol use disorder (AUD) is unclear. The present study aimed to investigate the predictive ability of FIB-4 for all-cause mortality in critically ill AUD patients and the association between them.

METHODS

A total of 2528 AUD patients were included using the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. FIB-4 was calculated for each patient using the existing formula. The patients were equally divided into four groups based on the quartiles of FIB-4. Multivariate logistic regression and Cox proportional hazard model were used to evaluate the association of FIB-4 with in-hospital mortality, 28-day mortality and 1-year mortality. Kaplan-Meier curves were used to analyse the incidence of 28-day mortality among four groups.

RESULTS

FIB-4 was positively associated with 28-day mortality of AUD patients with hazard ratio (HR) of 1.354 [95% confidence interval (CI) 1.192-1.538]. There were similar trends in the in-hospital mortality [odds ratio (OR): 1.440, 95% CI (1.239-1.674)] and 1-year mortality [HR: 1.325, 95% CI (1.178-1.490)].

CONCLUSION

Increased FIB-4 is associated with greater in-hospital mortality, 28-day mortality and 1-year mortality in critically ill AUD patients.

Modified Buyang Huanwu Decoction alleviates diabetic liver injury via inhibiting oxidative stress in db/db mice

OBJECTIVES

In diabetes, chronic hyperglycemia increases the overactivation of oxidative phosphorylation of mitochondria in the liver, resulting in oxidative stress (OS) damage. The Nrf2 signaling pathway plays a key role in preventing hepatic oxidative injury and inflammation. This study aims to investigate the therapeutic effect and mechanism of Modified Buyang Huanwu Decoction (mBYHWD) on diabetic liver injury (DLI) by regulating oxidative stress mediated by Nrf2 signaling pathway.

METHODS

The experiment was divided into three groups: a control group (db/m mice, Con), a diabetes model group (db/db mice, Mod), and a traditional Chinese medicine group (db/m mice, mBYHWD). Post-treatment, serum from each group was analyzed to assess changes of blood glucose, blood lipid, and liver function. These results were combined with data mining to explore the possible pathogenesis of DLI. Liver tissues were collected to observe the pathological morphology and detect related proteins.

RESULTS

The results demonstrated that mBYHWD significantly reduced blood lipids and improved liver function following diabetic liver injury. The histopathological results demonstrated that mBYHWD could significantly ameliorate damage of diabetic hepatocytes. Protein analysis revealed that mBYHWD treatment significantly increased the expression of antioxidant proteins in diabetic liver tissue and inhibited inflammation.

CONCLUSIONS

The therapeutic mechanism of mBYHWD on DLI may involve activating the Nrf2 signaling pathway to improve oxidative stress, inhibit inflammation, and reduce liver tissue fibrosis.

Efferocytosis in liver disease

The process of dead cell clearance by phagocytic cells, called efferocytosis, prevents inflammatory cell necrosis and promotes resolution and repair. Defective efferocytosis contributes to the progression of numerous diseases in which cell death is prominent, including liver disease. Many gaps remain in our understanding of how hepatic macrophages carry out efferocytosis and how this process goes awry in various types of liver diseases. Thus far, studies have suggested that, upon liver injury, liver-resident Kupffer cells and infiltrating monocyte-derived macrophages clear dead cells, limit inflammation, and, through macrophage reprogramming, repair liver damage. However, in unusual settings, efferocytosis can promote liver disease. In this review, we will focus on efferocytosis in various types of acute and chronic liver diseases, including metabolic dysfunction-associated steatohepatitis. Understanding the mechanisms and consequences of efferocytosis by hepatic macrophages has the potential to shed new light on liver disease pathophysiology and to guide new treatment strategies to prevent disease progression.

Human Precision-Cut Liver Slices: A Potential Platform to Study Alcohol-Related Liver Disease

Alcohol-related liver disease (ALD) encompasses a range of pathological conditions that are complex to study at the clinical and preclinical levels. Despite the global burden of ALD, there is a lack of effective treatments, and mortality is high. One of the reasons for the unsuccessful development of novel therapies is that experimental studies are hindered by the challenge of recapitulating this multifactorial disorder in vitro, including the contributions of hepatotoxicity, impaired lipid metabolism, fibrosis and inflammatory cytokine storm, which are critical drivers in the pathogenesis of ALD in patients and primary targets for drug development. Here, we present the unique characteristics of the culture of human precision-cut liver slices (PCLS) to replicate key disease processes in ALD. PCLS were prepared from human liver specimens and treated with ethanol alone or in combination with fatty acids and lipopolysaccharide (FA + LPS) for up to 5 days to induce hepatotoxic, inflammatory and fibrotic events associated with ALD. Alcohol insult induced hepatocyte death which was more pronounced with the addition of FA + LPS. This mixture showed a significant increase in the cytokines conventionally associated with the prototypical inflammatory response observed in severe ALD, and interestingly, alcohol alone exhibited a different effect. Profibrogenic activation was also observed in the slices and investigated in the context of slice preparation. These results support the versatility of this organotypic model to study different pathways involved in alcohol-induced liver damage and ALD progression and highlight the applicability of the PCLS for drug discovery, confirming their relevance as a bridge between preclinical and clinical studies.

Dysregulated Cyclic Nucleotide Metabolism in Alcohol-Associated Steatohepatitis: Implications for Novel Targeted Therapies

BACKGROUND

Cyclic nucleotides are second messengers, which play significant roles in numerous biological processes. Previous work has shown that cAMP and cGMP signaling regulates various pathways in liver cells, including Kupffer cells, hepatocytes, hepatic stellate cells, and cellular components of hepatic sinusoids. Importantly, it has been shown that cAMP levels and enzymes involved in cAMP homeostasis are affected by alcohol. Although the role of cyclic nucleotide signaling is strongly implicated in several pathological pathways in liver diseases, studies describing the changes in genes regulating cyclic nucleotide metabolism in ALD are lacking.

METHODS

Male C57B/6 mice were used in an intragastric model of alcohol-associated steatohepatitis (ASH). Liver injury, inflammation, and fibrogenesis were evaluated by measuring plasma levels of injury markers, liver tissue cytokines, and gene expression analyses. Liver transcriptome analysis was performed to examine the effects of alcohol on regulators of cyclic AMP and GMP levels and signaling. cAMP and cGMP levels were measured in mouse livers as well as in livers from healthy human donors and patients with alcohol-associated hepatitis (AH).

RESULTS

Our results show significant changes in several phosphodiesterases (PDEs) with specificity to degrade cAMP (Pde4a, Pde4d, and Pde8a) and cGMP (Pde5a, Pde6d, and Pde9a), as well as dual-specificity PDEs (Pde1a and Pde10a) in ASH mouse livers. Adenylyl cyclases (ACs) 7 and 9, which are responsible for cAMP generation, were also affected by alcohol. Importantly, adenosine receptor 1, which has been implicated in the pathogenesis of liver diseases, was significantly increased by alcohol. Adrenoceptors 1 and 3 (Adrb), which couple with stimulatory G protein to regulate cAMP and cGMP signaling, were significantly decreased. Additionally, beta arrestin 2, which interacts with cAMP-specific PDE4D to desensitize G-protein-coupled receptor to generate cAMP, was significantly increased by alcohol. Notably, we observed that cAMP levels are much higher than cGMP levels in the livers of humans and mice; however, alcohol affected them differently. Specifically, cGMP levels were higher in patients with AH and ASH mice livers compared with controls. As expected, these changes in liver cyclic nucleotide signaling were associated with increased inflammation, steatosis, apoptosis, and fibrogenesis.

CONCLUSIONS

These data strongly implicate dysregulated cAMP and cGMP signaling in the pathogenesis of ASH. Future studies to identify changes in these regulators in a cell-specific manner could lead to the development of novel targeted therapies for ASH.

Proteomics and network pharmacology of Ganshu Nuodan capsules in the prevention of alcoholic liver disease

Introduction

Ganshu Nuodan is a liver-protecting dietary supplement composed of Ganoderma lucidum (G. lucidum) spore powder, Pueraria montana (Lour.) Merr. (P. montana), Salvia miltiorrhiza Bunge (S. miltiorrhiza) and Astragalus membranaceus (Fisch.) Bunge. (A. membranaceus). However, its pharmacodynamic material basis and mechanism of action remain unknown.

Methods

A mouse model of acute alcohol liver disease (ALD) induced by intragastric administration of 50% alcohol was used to evaluate the hepatoprotective effect of Ganshu Nuodan. The chemical constituents of Ganshu Nuodan were comprehensively identified by UPLC-QTOF/MS, and then its pharmacodynamic material basis and potential mechanism of action were explored by proteomics and network pharmacology.

Results

Ganshu Nuodan could ameliorate acute ALD, which is mainly manifested in the significant reduction of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum and malondialdehyde (MDA) content in liver and the remarkably increase of glutathione (GSH) content and superoxide dismutase (SOD) activity in liver. Totally 76 chemical constituents were identified from Ganshu Nuodan by UPLC-QTOF/MS, including 21 quinones, 18 flavonoids, 11 organic acids, 7 terpenoids, 5 ketones, 4 sterols, 3 coumarins and 7 others. Three key signaling pathways were identified via proteomics studies, namely Arachidonic acid metabolism, Retinol metabolism, and HIF-1 signaling pathway respectively. Combined with network pharmacology and molecular docking, six key targets were subsequently obtained, including Ephx2, Lta4h, Map2k1, Stat3, Mtor and Dgat1. Finally, these six key targets and their related components were verified by molecular docking, which could explain the material basis of the hepatoprotective effect of Ganshu Nuodan.

Conclusion

Ganshu Nuodan can protect acute alcohol-induced liver injury in mice by inhibiting oxidative stress, lipid accumulation and apoptosis. Our study provides a scientific basis for the hepatoprotective effect of Ganshu Nuodan in acute ALD mice and supports its traditional application.

Hyaluronan synthesis inhibition normalizes ethanol-enhanced hepatic stellate cell activation

BACKGROUND

Chronic ethanol overconsumption promotes alcohol-associated liver disease (ALD), characterized by hepatocyte injury, inflammation, hepatic stellate cell (HSC) activation, and fibrosis. Hyaluronan (HA) concentration is greater in livers and blood from advanced ALD patients than patients with advanced non-ALD. In the liver, HSCs are the major HA producers. The relationship between ethanol, HA, and HSC activation is incompletely understood. Thus, here, we tested the hypothesis that ethanol enhances HSC activation in a HA-dependent manner.

METHODS

Liver tissue microarrays (TMAs) containing steatotic livers from donors with or without a history of alcohol consumption were used to measure HA and collagen content. Mice were fed a moderate (2%, v/v) ethanol-containing diet or pair-fed control diet for 2 days, after which they were given a single carbon tetrachloride (CCl4 ) injection. To inhibit HA synthesis, we provided 4-methylumbelliferone (4MU) daily. We used LX2 cells, a human HSC cell line, to determine the impact ethanol had on LPS responses, with or without concurrent 4MU exposure.

RESULTS

CCl4 induced liver injury, but it did not differ between ethanol or control diet fed mice with or without 4MU treatment. Ethanol feeding enhanced CCl4 -induced hepatic HA content, which was paralleled by HA synthase (Has)2 transcript abundance; 4MU treatment normalized both. Consistently, HSC activation, assessed by measuring αSMA mRNA and protein, was induced by CCl4 exposure, enhanced by ethanol feeding, and normalized by 4MU. Hepatic transcripts, but not protein, for Ccl2 were enhanced by ethanol feeding and normalized by 4MU exposure. Finally, ethanol-exposed LX2 cells made more LPS-stimulated CCL2 mRNA and protein than cells not exposed to ethanol; 4MU prevented this.

CONCLUSION

These data show that ethanol augments HSC activation through HA synthesis and enhances hepatic profibrogenic features. Therefore, targeting HSC HA production could potentially attenuate liver disease in ALD patients.

Zonal expression of StARD1 and oxidative stress in alcoholic-related liver disease

Alcoholic-related liver disease (ALD) is one of the leading causes of chronic liver disease and morbidity. Unfortunately, the pathogenesis of ALD is still incompletely understood. StARD1 has emerged as a key player in other etiologies of chronic liver disease, and alcohol-induced liver injury exhibits zonal distribution. Here, we report that StARD1 is predominantly expressed in perivenous (PV) zone of liver sections from mice-fed chronic and acute-on-chronic ALD models compared to periportal (PP) area and is observed as early as 10 days of alcohol feeding. Ethanol and chemical hypoxia induced the expression of StARD1 in isolated primary mouse hepatocytes. The zonal-dependent expression of StARD1 resulted in the accumulation of cholesterol in mitochondria and increased lipid peroxidation in PV hepatocytes compared to PP hepatocytes, effects that were abrogated in PV hepatocytes upon hepatocyte-specific Stard1 KO mice. Transmission electron microscopy indicated differential glycogen and lipid droplets content between PP and PV areas, and alcohol feeding decreased glycogen content in both areas while increased lipid droplets content preferentially in PV zone. Moreover, transmission electron microscopy revealed that mitochondria from PV zone exhibited reduced length with respect to PP area, and alcohol feeding increased mitochondrial number, particularly, in PV zone. Extracellular flux analysis indicated lower maximal respiration and spared respiratory capacity in control PV hepatocytes that were reversed upon alcohol feeding. These findings reveal a differential morphology and functional activity of mitochondria between PP and PV hepatocytes following alcohol feeding and that StARD1 may play a key role in the zonal-dependent liver injury characteristic of ALD.

Chronic-binge ethanol feeding aggravates systemic dyslipidemia in Ldlr-/- mice, thereby accelerating hepatic fibrosis

Objective

Chronic ethanol consumption is known to cause alcohol-associated liver disease, which poses a global health concern as almost a quarter of heavy drinkers develop severe liver damage. Alcohol-induced liver disease ranges from a mild, reversible steatotic liver to alcoholic steatohepatitis and irreversible liver fibrosis and cirrhosis, ultimately requiring liver transplantation. While ethanol consumption is associated with dysregulated lipid metabolism and altered cholesterol homeostasis, the impact of dyslipidemia and pre-existing hypercholesterolemia on the development of alcohol-associated liver disease remains to be elucidated.

Design

To address the influence of systemic dyslipidemia on ethanol-induced liver disease, chronic-binge ethanol feeding was applied to female C57BL/6J (wild type) mice and mice deficient for the low-density lipoprotein receptor (Ldlr-/-), which display a human-like lipoprotein profile with elevated cholesterol and triglyceride levels in circulation. Respective control groups were pair-fed an isocaloric diet.

Results

Chronic-binge ethanol feeding did not alter systemic lipid levels in wild type mice. While increased systemic cholesterol levels in Ldlr-/- mice were not affected by ethanol feeding, chronic-binge ethanol diet aggravated elevated plasma triglyceride levels in Ldlr-/- mice. Despite higher circulatory triglyceride levels in Ldlr-/- mice, hepatic lipid levels and the development of hepatic steatosis were not different from wild type mice after ethanol diet, while hepatic expression of genes related to lipid metabolism (Lpl) and transport (Cd36) showed minor changes. Immunohistochemical assessment indicated a lower induction of infiltrating neutrophils in the livers of ethanol-fed Ldlr-/- mice compared to wild type mice. In line, hepatic mRNA levels of the pro-inflammatory genes Ly6g, Cd11b, Ccr2, Cxcl1 and F4/80 were reduced, indicating less inflammation in the livers of Ldlr-/- mice which was associated with reduced Tlr9 induction. While systemic ALT and hepatic MDA levels were not different, Ldlr-deficient mice showed accelerated liver fibrosis development after chronic-binge ethanol diet than wild type mice, as indicated by increased levels of Sirius Red staining and higher expression of pro-fibrotic genes Tgfb, Col1a1 and Col3a1. Ldlr-/- and wild type mice had similar plasma ethanol levels and did not show differences in the hepatic mRNA levels of Adh1 and Cyp2e1, important for ethanol metabolism.

Conclusion

Our results highlight that chronic-binge ethanol feeding enhances systemic dyslipidemia in Ldlr-/- mice which might accelerate the development of hepatic fibrosis, independent of hepatic lipid levels.

Alcohol-related liver disease: also a question of what you drink?

Excessive alcohol intake is still among the leading causes of chronic liver diseases. Epidemiological studies suggest that per capita consumption of alcohol from various alcohol beverages e.g., beer, wine, or spirits, differs markedly between different areas of the world. Studies further suggest that different alcoholic beverages may impact the development of alcohol-related liver diseases (ALD) differentially. Specifically, results of several more recent epidemiological studies suggest that consumption of wine and herein especially of red wine may be less harmful in relation to the development of liver diseases than the intake of hard spirits. Results of studies evaluating the effects of beer on the development of ALD in humans are rather contradictory. Here, results of studies assessing the impact of wine, beer, and spirits on the development of ALD as well as possible underlying mechanisms are summarized and discussed.

Mangiferin for the Management of Liver Diseases: A Review

The liver is a digestive and metabolic organ, and several factors can induce liver damage, which is a severe threat to human health. As a natural polyphenolic compound, mangiferin belongs to xanthone glucoside and mainly exists in many plants, such as mango. It is notorious that mangiferin has remarkable pharmacological activities such as anti-inflammatory, anti-tumor, antioxidative stress, antiviral and so on. Emerging evidence indicates the therapeutic benefits of mangiferin against liver disease, including liver injury, nonalcoholic fatty liver disease, alcoholic liver disease, liver fibrosis, and hepatocellular carcinoma. This review aims to summarize the possible underlying signaling mediated by mangiferin in liver disease treatment and the available findings of mangiferin, which can be used to treat different liver diseases and may contribute to mangiferin as a therapeutic agent for liver disease in humans.