The intersection between alcohol-related liver disease and nonalcoholic fatty liver disease

Long-term clinical outcomes in steatotic liver disease and incidence of liver-related events, cardiovascular events and all-cause mortality

BACKGROUND

A multi-society consensus group proposed a new nomenclature for steatotic liver disease (SLD) including metabolic-dysfunction associated steatotic liver disease (MASLD), MASLD and increased alcohol intake (MetALD) and alcohol-associated liver disease (ALD). However, the risk of liver-related events, major adverse cardiovascular events (MACE) and all-cause mortality among various sub-groups is unknown.

AIMS

To evaluate the risk of liver-related events, MACE and death among patients with SLD.

METHODS

We conducted a nationwide, population-based study and enrolled 761,400 patients diagnosed with MASLD, MetALD or ALD. The primary endpoint was the occurrence of liver-related events, MACE and death in patients with MASLD, MetALD and ALD.

RESULTS

The cumulative incidence of liver-related events and death were highest in ALD, followed by MetALD and MASLD (p < 0.001 for both liver-related events and death), while the incidence of MACE was highest in MASLD, followed by MetALD and ALD (p < 0.001). Using MASLD as the reference and adjusting for age, sex, smoking, diabetes mellitus, dyslipidaemia and hypertension, the adjusted hazard ratios (95% confidence intervals) for liver-related events, MACE and death in MetALD were 1.42 (1.1-1.8), 0.68 (0.63-0.73) and 1.13 (0.98-1.3), respectively. In ALD, they were 3.42 (2.6-4.6), 0.58 (0.49-0.67) and 1.60 (1.3-2.0), respectively, for liver-related events, MACE and death.

CONCLUSIONS

The new consensus nomenclature can be used to stratify the risk of complications and prognosis. The nomenclature is beneficial for risk stratification and identifying new mechanisms for disease-specific therapeutic implications.

Endogenous ethanol production in health and disease

The gut microbiome exerts metabolic actions on distal tissues and organs outside the intestine, partly through microbial metabolites that diffuse into the circulation. The disruption of gut homeostasis results in changes to microbial metabolites, and more than half of the variance in the plasma metabolome can be explained by the gut microbiome. Ethanol is a major microbial metabolite that is produced in the intestine of nearly all individuals; however, elevated ethanol production is associated with pathological conditions such as metabolic dysfunction-associated steatotic liver disease and auto-brewery syndrome, in which the liver's capacity to metabolize ethanol is surpassed. In this Review, we describe the mechanisms underlying excessive ethanol production in the gut and the role of ethanol catabolism in mediating pathogenic effects of ethanol on the liver and host metabolism. We conclude by discussing approaches to target excessive ethanol production by gut bacteria.

Combined Insults of a MASH Diet and Alcohol Binges Activate Intercellular Communication and Neutrophil Recruitment via the NLRP3-IL-1β Axis in the Liver

Binge drinking in obese patients positively correlates with accelerated liver damage and liver-related death. However, the underlying mechanism and the effect of alcohol use on the progression of metabolic-dysfunction-associated steatotic liver disease (MASLD) remain unexplored. Here, we show that short-term feeding of a metabolic-dysfunction-associated steatohepatitis (MASH) diet plus daily acute alcohol binges for three days induce liver injury and activation of the NLRP3 inflammasome. We identify that a MASH diet plus acute alcohol binges promote liver inflammation via increased infiltration of monocyte-derived macrophages, neutrophil recruitment, and NET release in the liver. Our results suggest that both monocyte-derived macrophages and neutrophils are activated via NLRP3, while the administration of MCC950, an NLRP3 inhibitor, dampens these effects.In this study, we reveal important intercellular communication between hepatocytes and neutrophils. We discover that the MASH diet plus alcohol induces IL-1β via NLRP3 activation and that IL-1β acts on hepatocytes and promotes the production of CXCL1 and LCN2. In turn, the increase in these neutrophils recruits chemokines and causes further infiltration and activation of neutrophils in the liver. In vivo administration of the NLRP3 inhibitor, MCC950, improves the early phase of MetALD by preventing liver damage, steatosis, inflammation, and immune cells recruitment.

The burden of liver disease in Latin America

Liver disease poses a substantial burden in Latin America. This burden is primarily attributed to a high level of alcohol consumption and the increasing prevalence of risk factors associated with metabolic dysfunction-associated steatotic liver disease (MASLD), such as sedentary lifestyles, easy access to ultra-processed foods, obesity, and type 2 diabetes mellitus. These epidemiological trends are cause for concern, especially considering that there are significant challenges in addressing them due to disparities in access to liver disease screening and care. In this article, we aim to provide an overview of the current situation regarding liver disease in Latin America. We also discuss recent multinational proposals designed to address the growing MASLD burden via its integration into existing non-communicable diseases policies, at both local and global levels. Additionally, we emphasize the urgent need to establish effective public health policies that target both MASLD risk factors and excessive alcohol consumption. Furthermore, we discuss the development of liver transplantation programs, areas for improvement in medical education and research capabilities, and how the fostering of extensive collaboration among all stakeholders is crucial for addressing liver disease in the region.

Larsucosterol: endogenous epigenetic regulator for treating chronic and acute liver diseases

Larsucosterol, a potent endogenous epigenetic regulator, has been reported to play a significant role in lipid metabolism, inflammatory responses, and cell survival. The administration of larsucosterol has demonstrated a reduction in lipid accumulation within hepatocytes and the attenuation of inflammatory responses induced by lipopolysaccharide (LPS) and TNFα in macrophages, alleviating LPS- and acetaminophen (ATMP)-induced multiple organ injury, and decreasing mortalities in animal models. Results from phase 1 and 2 clinical trials have shown that larsucosterol has potential as a biomedicine for the treatment of acute and chronic liver diseases. Recent evidence suggests that larsucosterol is a promising candidate for treating alcohol-associated hepatitis with positive results from a phase 2a clinical trial, and for metabolic dysfunction-associated steatohepatitis (MASH) from a phase 1b clinical trial. In this review, we present a culmination of our recent research efforts spanning two decades. We summarize the discovery, physiological and pharmacological mechanisms, and clinical applications of larsucosterol. Furthermore, we elucidate the pathophysiological pathways of metabolic dysfunction-associated steatotic liver diseases (MASLD), metabolic dysfunction-associated steatohepatitis (MASH), and acute liver injuries. A central focus of the review is the exploration of the therapeutic potential of larsucosterol in treating life-threatening conditions, including acetaminophen overdose, endotoxin shock, MASLD, MASH, hepatectomy, and alcoholic hepatitis.

Waitlisting and liver transplantation for MetALD in the United States: An analysis of the UNOS national registry

BACKGROUND AND AIMS

The new steatotic liver disease (SLD) nomenclature introduced metabolic and alcohol-associated liver disease (MetALD), describing the intersection of metabolic dysfunction-associated steatotic liver disease and alcohol-associated liver disease. Waitlisting and liver transplantation for MetALD are not well defined. We aimed to develop and validate an algorithm for identifying SLD phenotypes and assessing trends in waitlisting and transplant outcomes.

APPROACH AND RESULTS

We conducted a retrospective cohort study using the United Network for Organ Sharing registry, supplemented with detailed single-center data. We developed 5 candidate algorithms for SLD classification and calculated their diagnostic performance. Trends in waitlist registrations and transplants were estimated, and competing risk analyses and Cox regression models were conducted to assess waitlist removal and posttransplant outcomes among SLD phenotypes. The best-performing algorithm demonstrated substantial agreement (weighted kappa, 0.62) for SLD phenotypes, with acceptable sensitivity (73%) for MetALD. Between 2002 and 2022, waitlist registrations and transplants for MetALD increased 2.9-fold and 3.3-fold, respectively. Since 2013, there has been a significant increase in the absolute number of waitlist registrations (122 per year; 95% CI, 111-133) and transplants (107 per year; 95% CI, 94-120) for MetALD. Patients with MetALD experienced higher waitlist removal (adjusted subdistribution hazard ratio, 1.10; 95% CI, 1.03-1.17), all-cause mortality (adjusted hazard ratio, 1.13; 95% CI, 1.03-1.23), and graft failure (adjusted hazard ratio, 1.12; 95% CI, 1.03-1.21) than those with alcohol-associated liver disease.

CONCLUSIONS

We developed and validated an algorithm for identifying SLD phenotypes in UNOS. MetALD is the third leading etiology among those waitlisted and underwent transplantation, exhibiting worse pretransplantation and posttransplantation outcomes compared to alcohol-associated liver disease. Identifying and addressing factors determining poor outcomes is crucial in this patient population.

The Janus of a disease: Diabetes and metabolic dysfunction-associated fatty liver disease

Metabolic Dysfunction-Associated Fatty Liver Disease and Diabetes Mellitus are two prevalent metabolic disorders that often coexist and synergistically contribute to the progression of each other. Several pathophysiological pathways are involved in the association, including insulin resistance, inflammation, and lipotoxicity, providing a foundation for understanding the complex interrelationships between these conditions. The presence of MASLD has a significant impact on diabetes risk and the development of microvascular and macrovascular complications, and diabetes significantly contributes to an increased risk of liver fibrosis progression in MASLD and the development of hepatocellular carcinoma. Moreover, both pathologies have a synergistic effect on cardiovascular events and mortality. Therapeutic interventions targeting MASLD and diabetes are discussed, considering lifestyle modifications, pharmacological agents, and emerging treatment modalities. The review also addresses the challenges in managing these comorbidities, such as the need for personalized approaches and the potential impact on cardiovascular health. The insights gleaned from this analysis can inform clinicians, researchers, and policymakers in developing integrated strategies for preventing, diagnosing, and managing these metabolic disorders.

Alcohol-related liver disease: A global perspective

Alcohol-associated liver disease (ALD) represents one of the deadliest yet preventable consequences of excessive alcohol use. It represents 5.1 % of the global burden of disease, mainly involving the productive-age population (15-44 years) and leading to an increased mortality risk from traffic road injuries, suicide, violence, cardiovascular disease, neoplasms, and liver disease, among others, accounting for 5.3 % of global deaths. Daily alcohol consumption, binge drinking (BD), and heavy episodic drinking (HED) are the patterns associated with a higher risk of developing ALD. The escalating global burden of ALD, even exceeding what was predicted, is the result of a complex interaction between the lack of public policies that regulate alcohol consumption, low awareness of the scope of the disease, late referral to specialists, underuse of available medications, insufficient funds allocated to ALD research, and non-predictable events such as the COVID-19 pandemic, where increases of up to 477 % in online alcohol sales were registered in the United States. Early diagnosis, referral, and treatment are pivotal to achieving the therapeutic goal in patients with alcohol use disorder (AUD) and ALD, where complete alcohol abstinence and prevention of alcohol relapse are expected to enhance overall survival. This can be achieved through a combination of cognitive behavioral, motivational enhancement and pharmacological therapy. Furthermore, the appropriate use of available pharmacological therapy and implementation of public policies that comprehensively address this disease will make a real difference.

Hepatic mitochondrial reductive stress in the pathogenesis and treatment of steatotic liver disease

Steatotic liver diseases (SLDs) affect one-third of the population, but the pathogenesis underlying these diseases is not well understood, limiting the available treatments. A common factor in SLDs is increased hepatic mitochondrial reductive stress, which occurs as a result of excessive lipid and alcohol metabolism. Recent research has also shown that genetic risk factors contribute to this stress. This review aims to explore how these risk factors increase hepatic mitochondrial reductive stress and how it disrupts hepatic metabolism, leading to SLDs. Additionally, the review will discuss the latest clinical studies on pharmaceutical treatments for SLDs, specifically peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists, thyroid hormone receptor (THR) agonists, acetyl-CoA carboxylase (ACC) inhibitors, and mitochondrial uncouplers. These treatments have a common effect of decreasing hepatic mitochondrial reductive stress, which has been largely overlooked.

Global and regional burden of alcohol-associated liver disease and alcohol use disorder in the elderly

Background & Aims

Alcohol-associated liver diseases (ALDs) and alcohol use disorder (AUD) pose a global health risk. AUD is underrecognized in the elderly, and the burden of AUD complications, including ALD, may increase with aging populations and rising alcohol intake. However, there is a lack of epidemiological evidence on AUD and ALD in the elderly.

Methods

Using the Global Burden of Disease Study 2019, we analyzed the prevalence, mortality, disability-adjusted life years (DALYs), age-standardized rates (ASRs), and temporal change from 2000 to 2019 of ALD and AUD in the overall population and the elderly (65-89 years). The findings were categorized by sex, region, nation, and sociodemographic index.

Results

The prevalence rates of ALD in the elderly were higher than those in adolescents and young adults, whereas AUD levels were lower than those in adolescents and young adults. In 2019, there were 9.39 million cases (8.69% of cases in the overall population) of AUD, 3.23 million cases (21.8% of cases in the overall population) of alcohol-associated cirrhosis, and 68,468 cases (51.27% of cases in the overall population) of liver cancer from alcohol among the elderly. ASRs of the prevalence of ALD and AUD in the elderly increased in most regions; on the contrary, ASRs of death and DALYs decreased in most regions. Nevertheless, ASRs of death and DALYs from liver cancer from alcohol increased in many areas.

Conclusions

Our findings highlighted the increased prevalence of ALD in the elderly, with a burden of AUD comparable with that in the overall population. Public health strategies on ALD and AUD targeting the elderly are urgently needed.

Impact and implications

The burden of alcohol-associated liver disease (ALD) and alcohol use disorder (AUD) is increasing. Advances in healthcare and education have resulted in a remarkable spike in life expectancy and a consequential population aging. Nevertheless, little is known about the epidemiology of ALD and AUD in the elderly. Our study indicates the increasing burden of ALD and AUD in the elderly population, necessitating early detection, intervention, and tailored care to the unique needs and complexities faced by older individuals grappling with these conditions.

Unveiling the cancer risk nexus of the steatotic liver

Steatotic liver, characterized by the accumulation of fat in the liver, poses significant health risks including metabolic dysfunction-associated steatotic liver disease (MASLD) and an elevated risk of primary liver cancer. Emerging evidence indicates a robust association between steatotic liver and increased susceptibility to extrahepatic primary cancers and their metastases. The deposition of fat induces dynamic changes in hepatic microenvironments, thereby fostering inflammation and immune responses that enhance liver metastasis from extrahepatic primary cancers. This review explores the impact of steatotic liver on hepatic carcinogenesis and metastasis from extrahepatic cancers, with a specific focus on hepatocyte-derived factors and the immune microenvironment. By emphasizing novel conclusions, this article underscores the timely relevance of understanding these intricate connections.

Alcohol Drinking Impacts on Adiposity and Steatotic Liver Disease: Concurrent Effects on Metabolic Pathways and Cardiovascular Risks

PURPOSE OF REVIEW

This integrative search aimed to provide a scoping overview of the relationships between the benefits and harms of alcohol drinking with cardiovascular events as associated to body fat mass and fatty liver diseases, as well as offering critical insights for precision nutrition research and personalized medicine implementation concerning cardiovascular risk management associated to ethanol consumption.

RECENT FINDINGS

Frequent alcohol intake could contribute to a sustained rise in adiposity over time. Body fat distribution patterns (abdominal/gluteus-femoral) and intrahepatic accumulation of lipids have been linked to adverse cardiovascular clinical outcomes depending on ethanol intake. Therefore, there is a need to understand the complex interplay between alcohol consumption, adipose store distribution, metabolic dysfunction-associated steatotic liver disease (MASLD), and cardiovascular events in adult individuals. The current narrative review deals with underconsidered and apparently conflicting benefits concerning the amount of alcohol intake, ranging from abstention to moderation, and highlights the requirements for additional robust methodological studies and trials to interpret undertrained and existing controversies. The conclusion of this review emphasizes the need of newer multifaceted clinical approaches for precision medicine implementation, considering epidemiological strategies and pathophysiological mechanistic. Newer investigations and trials should be derived and performed particularly focusing both on alcohol's objective consequences as putatively mediated by fat deposition, including associated roles in fatty liver disease as well as to differentiate the impact of different levels of alcohol consumption (absence or moderation) concerning cardiovascular risks and accompanying clinical manifestations. Indeed, the threshold for the safe consumption of alcoholic drinks remains to be fully elucidated.

Association between public health policies on alcohol and worldwide cancer, liver disease and cardiovascular disease outcomes

BACKGROUND & AIMS

The long-term impact of alcohol-related public health policies (PHPs) on disease burden is unclear. We aimed to assess the association between alcohol-related PHPs and alcohol-related health consequences.

METHODS

We conducted an ecological multi-national study including 169 countries. We collected data on alcohol-related PHPs from the WHO Global Information System of Alcohol and Health 2010. Data on alcohol-related health consequences between 2010-2019 were obtained from the Global Burden of Disease database. We classified PHPs into five items, including criteria for low, moderate, and strong PHP establishment. We estimated an alcohol preparedness index (API) using multiple correspondence analysis (0 lowest and 100 highest establishment). We estimated an incidence rate ratio (IRR) for outcomes according to API using adjusted multilevel generalized linear models with a Poisson family distribution.

RESULTS

The median API in the 169 countries was 54 [IQR 34.9-76.8]. The API was inversely associated with alcohol use disorder (AUD) prevalence (IRR 0.13; 95% CI 0.03-0.60; p = 0.010), alcohol-associated liver disease (ALD) mortality (IRR 0.14; 95% CI 0.03-0.79; p = 0.025), mortality due to neoplasms (IRR 0.09; 95% CI 0.02-0.40; p = 0.002), alcohol-attributable hepatocellular carcinoma (HCC) (IRR 0.13; 95% CI 0.02-0.65; p = 0.014), and cardiovascular diseases (IRR 0.09; 95% CI 0.02-0.41; p = 0.002). The highest associations were observed in the Americas, Africa, and Europe. These associations became stronger over time, and AUD prevalence was significantly lower after 2 years, while ALD mortality and alcohol-attributable HCC incidence decreased after 4 and 8 years from baseline API assessment, respectively (p <0.05).

CONCLUSIONS

The API is a valuable instrument to quantify the robustness of alcohol-related PHP establishment. Lower AUD prevalence and lower mortality related to ALD, neoplasms, alcohol-attributable HCC, and cardiovascular diseases were observed in countries with a higher API. Our results encourage the development and strengthening of alcohol-related policies worldwide.

IMPACT AND IMPLICATIONS

We first developed an alcohol preparedness index, an instrument to assess the existence of alcohol-related public policies for each country. We then evaluated the long-term association of the country's alcohol preparedness index in 2010 with the burden of chronic liver disease, hepatocellular carcinoma, other neoplasms, and cardiovascular disease. The strengthening of alcohol-related public health policies could impact long-term mortality rates from cardiovascular disease, neoplasms, and liver disease. These conditions are the main contributors to the global burden of disease related to alcohol use. Over time, this association has not only persisted but also grown stronger. Our results expand the preliminary evidence regarding the importance of public health policies in controlling alcohol-related health consequences.

Validation of the new nomenclature of steatotic liver disease in patients with a history of excessive alcohol intake: an analysis of data from a prospective cohort study

BACKGROUND

Steatotic liver disease is a new overarching term that includes metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related steatotic liver disease (MetALD), and alcohol-related liver disease (ALD). We aimed to validate the prognostic importance of MASLD, MetALD, and ALD as steatotic liver disease subclasses.

METHODS

Between April 18, 2013, and Sept 17, 2018, we prospectively recruited patients aged 18-75 years with current or previous excessive alcohol intake (>24 g/day for women and >36 g/day for men) for at least a year and no previous hepatic decompensation from the Department of Gastroenterology and Hepatology at Odense University Hospital (Odense, Denmark). Participants were followed up until Sept 15, 2022. Here, we characterise these patients according to steatotic liver disease subclasses. We classified patients as having MASLD, MetALD, or ALD in accordance with the nomenclature definitions, on the basis of metabolic comorbidity and self-reported average alcohol intake in the 3 months leading up to inclusion. Histological scoring was done by a pathologist who was masked to the clinical data. We compared prognoses between classes using Cox regression analyses on hepatic decompensation and overall mortality as the two outcome measures. Patients not meeting the criteria for steatotic liver disease were classified as no steatotic liver disease and served as a reference group.

FINDINGS

We enrolled 446 patients with a history of excessive alcohol intake were included in this analysis (334 [75%] were male and 112 [25%] were female; median age 56 years [SD 10]). Cirrhosis was present in 58 (13%), and 435 (98%) had at least one cardiometabolic risk factor. 321 (72%) met steatotic liver disease criteria and 125 (28%) did not have steatotic liver disease, meaning no evident liver steatosis and no significant fibrosis (≥F2). Of the 321 patients with steatotic liver disease, six (2%) were identified as having ALD due to the absence of cardiometabolic risk factors. The remaining 315 (98%) patients presented with at least one cardiometabolic risk factor. Of these patients, 153 (49%) had MASLD, 76 (24%) had MetALD, and 86 (27%) had ALD. During follow-up, 67 (15%) of 446 patients decompensated and 97 (22%) died (median follow-up 70 months [IQR 53-94]). Patients with steatotic liver disease had a significantly higher risk of hepatic decompensation and overall mortality than those without steatotic liver disease, independent of age, sex, and liver stiffness. The risk of decompensation increased in a stepwise manner from MASLD (hazard ratio 4·73 [95% CI 1·03-21·6]), through MetALD (7·69 [1·66-35·6]), to ALD (10·2 [2·24-46·4]). Similarly, overall mortality increased from MASLD (HR 2·30 [95% CI 1·08-4·90]), through MetALD (2·94 [1·31-6·58]), to ALD (3·57 [1·64-7·80]), independent of age, sex, and liver stiffness.

INTERPRETATION

Steatotic liver disease and its subclasses portend distinct prognoses. There is a need to specify how historical alcohol intake should be integrated into the nomenclature and risk stratification of steatotic liver disease.

FUNDING

EU Horizon 2020 Research and Innovation Program.

Promoting In Vivo NIR-II Fluorescent Imaging for Lipid in Lipid Metabolism Diseases Diagnosis

Lipid metabolism diseases have become a tremendous risk worldwide, along with the development of productivity and particular attention to public health. It has been an urgent necessity to exploit reliable imaging strategies for lipids and thus to monitor fatty liver diseases. Herein, by converting the NIR-I signal to the NIR-II signal with IR1061 for the monitoring of lipid, the in vivo imaging of fatty liver disease was promoted on the contrast and visual effect. The main advantages of the imaging promotion in this work included a long emission wavelength, rapid response, and high signal-background-ratio (SBR) value. After promoting the NIR-I signal to NIR-II signal, IR1061 achieved higher SBR value and exhibited a dose-dependent fluorescence intensity at 1100 nm along with the increase of the EtOH proportion as well as steady and selective optical responses toward liposomes. IR1061 was further applied in the in vivo imaging of lipid in fatty liver diseases. In spite of the differences in body weight gain and TC level between healthy mice and fatty liver diseases two models, IR1061 achieved high-resolution imaging in the liver region to monitor the fatty liver disease status. This work might be informatic for the clinical diagnosis and therapeutical treatments of fatty liver diseases.

New Nomenclature for Nonalcoholic Fatty Liver Disease: Understanding Metabolic Dysfunction-Associated Steatotic Liver Disease, Metabolic Dysfunction- and Alcohol-Associated Liver Disease, and Their Implications in Clinical Practice

In June 2023, under the patronage of the American Association for Study of Liver Disease, the European Association for Study of the Liver, and the Asociación Latinoamericana para el Estudio del Hígado with the involvement of 236 participants from around the world, a new nomenclature and definition for nonalcoholic fatty liver disease (NAFLD) has been proposed. Metabolic dysfunction-associated steatotic liver disease (MASLD) was defined as presence of hepatic steatosis and at least one of the cardiometabolic risk factors with alcohol intake less than 140 g/wk for women and 210 g/wk for men and no other causes of steatosis. A new entity called combined metabolic dysfunction- and alcohol-associated liver disease (MetALD) was created outside of pure MASLD for patients with metabolic dysfunction and alcohol intake greater than that allowed for MASLD (i.e., 140-350 g/wk for women and 210-420 g/wk for men). Recent studies have confirmed a 95% overlap between NAFLD and the new MASLD diagnostic criteria. Natural history, biomarkers, and thresholds of alcohol intake in MetALD group remains to be studied and validated.

MASLD treatment-a shift in the paradigm is imminent

MASLD prevalence is growing towards the leading cause of end-stage liver disease. Up to today, the most effective treatment is weight loss. Weight loss interventions are moving from lifestyle changes to bariatric surgery or endoscopy, and, more recently, to a new wave of anti-obesity drugs that can compete with bariatric surgery. Liver-targeted therapy is a necessity for those patients who already present liver fibrosis. The field is moving fast, and in the near future, we will testify to a disruptive change in MASLD treatment, similar to the paradigm-shift that occurred for hepatitis C almost one decade ago with direct antiviral agents.

Overexpression of Interleukin-8 Promotes the Progression of Fatty Liver to Nonalcoholic Steatohepatitis in Mice

Nonalcoholic steatohepatitis (NASH) is an advanced stage of fatty liver disease characterized by liver damage, inflammation, and fibrosis. Although neutrophil infiltration is consistently observed in the livers of patients with NASH, the precise role of neutrophil-recruiting chemokines and infiltrating neutrophils in NASH pathogenesis remains poorly understood. Here, we aimed to elucidate the role of neutrophil infiltration in the transition from fatty liver to NASH by examining hepatic overexpression of interleukin-8 (IL8), a major chemokine responsible for neutrophil recruitment in humans. Mice fed a high-fat diet (HFD) for 3 months developed fatty liver without concurrent liver damage, inflammation, and fibrosis. Subsequent infection with an adenovirus overexpressing human IL8 for an additional 2 weeks increased IL8 levels, neutrophil infiltration, and liver injury in mice. Mechanistically, IL8-induced liver injury was associated with the upregulation of components of the NADPH oxidase 2 complex, which participate in neutrophil oxidative burst. IL8-driven neutrophil infiltration promoted macrophage aggregate formation and upregulated the expression of chemokines and inflammatory cytokines. Notably, IL8 overexpression amplified factors associated with fibrosis, including collagen deposition and hepatic stellate cell activation, in HFD-fed mice. Collectively, hepatic overexpression of human IL8 promotes neutrophil infiltration and fatty liver progression to NASH in HFD-fed mice.

New insights into the molecular basis of alcohol abstinence and relapse in alcohol-associated liver disease

Alcohol use disorder remains a significant public health concern, affecting around 5% of adults worldwide. Novel pathways of damage have been described during the last years, providing insight into the mechanism of injury due to alcohol misuse beyond the direct effect of ethanol byproducts on the liver parenchyma and neurobehavioral mechanisms. Thus, the gut-liver-brain axis and immune system involvement could be therapeutic targets for alcohol use disorder. In particular, changes in gut microbiota composition and function, and bile acid homeostasis, have been shown with alcohol consumption and cessation. Alcohol can also directly disrupt intestinal and blood-brain barriers. Activation of the immune system can be triggered by intestinal barrier dysfunction and translocation of bacteria, pathogen-associated molecular patterns (such as lipopolysaccharide), cytokines, and damage-associated molecular patterns. These factors, in turn, promote liver and brain inflammation and the progression of liver fibrosis. Other involved mechanisms include oxidative stress, apoptosis, autophagy, and the release of extracellular vesicles and miRNA from hepatocytes. Potential therapeutic targets include gut microbiota (probiotics and fecal microbiota transplantation), neuroinflammatory pathways, as well as neuroendocrine pathways, for example, the ghrelin system (ghrelin receptor blockade), incretin mimetics (glucagon-like peptide-1 analogs), and the mineralocorticoid receptor system (spironolactone). In addition, support with psychological and behavioral treatments is essential to address the multiple dimensions of alcohol use disorder. In the future, a personalized approach considering these novel targets can contribute to significantly decreasing the alcohol-associated burden of disease.