Progression of non-alcoholic fatty liver disease and long-term outcomes: A nationwide paired liver biopsy cohort study

Advances in fluorescent probes of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the predominant chronic liver disease worldwide, with 20-30 % of individuals going on to develop non-alcoholic steatohepatitis (NASH), which could result in serious complications such as fibrosis, liver cirrhosis, and hepatocellular carcinoma. Since NAFLD is reversible in its early stages, early diagnosis is necessary. By using particular structural and functional designs, fluorescent probes can be made to detect NAFLD-related chemicals or biological processes with a high degree of sensitivity and selectivity. In this work, we summarize the existing fluorescent probes for identifying biomarkers in NAFLD, including microenvironment (viscosity, polarity), ROS, RNS, RSS, metal ions, enzymes, and RNA. Furthermore, future directions are envisioned to inform the creation of more accurate and reliable fluorescent probes for NAFLD diagnosis, emphasizing the benefits and challenges of fluorescence probes.

FGF2 Mediated USP42-PPARγ Axis Activation Ameliorates Liver Oxidative Damage and Promotes Regeneration

Liver regeneration is critical for maintaining whole-body homeostasis, especially under exposure to deadly chemical toxins. Understanding the molecular mechanisms underlying liver repair is critical for the development of intervention strategies to treat liver diseases. In this study, ubiquitin-specific Proteases 42 (USP42) is identified as a novel deubiquitinases (DUB) of peroxisome proliferators-activated receptor γ (PPARγ) in hepatocytes. This DUB interacted, deubiquitinated, and stabilized PPARγ, and increased PPARγ targeted proliferative and antioxidative gene expressions, which protects the liver from carbon tetrachloride (CCL4) induced oxidative injury and promotes liver regeneration. In addition, fibroblast growth factor 2 (FGF2) initiated USP42 expression and enhanced the interaction between USP42 and PPARγ during the liver regeneration process. Moreover, the PPARγ full agonist, rosiglitazone (RSG), possesses the ability to further reinforce the USP42-PPARγ interplay, which enlightens to construct of an extracellular vesicle-based targeting strategy to activate the liver USP42-PPARγ axis and promote liver regeneration. In summary, the work uncovers the importance of USP42-PPARγ axis-mediated liver tissue homeostasis and provides a promising regimen to target this protein-protein interplay for liver regeneration.

Hepatoprotective Effect of Kaempferol-A Review

Liver diseases, including chronic inflammation and related metabolic dysfunction-associated steatotic liver disease (MASLD), fibrosis and cirrhosis remain a growing global health burden. Currently, available pharmacotherapy for liver dysfunction has limited efficacy. Kaempferol, a naturally occurring flavonoid, has demonstrated significant hepatoprotective effects in preclinical models. This substance activates the SIRT1/AMPK signalling pathway, improves mitochondrial function, inhibits proinflammatory cytokine production via TLR4/NF-κB suppression and attenuates hepatic stellate cell activation by modulating the TGF-β/Smad pathway. In addition, kaempferol regulates the composition of the gut microbiota, thus improving bile acid metabolism and alleviating steatosis and fibrosis. This review presents an integrated analysis of recent in vitro and in vivo studies on the mode of action and utility of kaempferol in liver disease and hepatoprotection.

Insulin-induced gene 2 alleviates ischemia-reperfusion injury in steatotic liver by inhibiting GPX4-dependent ferroptosis

Hepatic steatosis significantly elevates the vulnerability of the graft to ischemia-reperfusion (I/R) injury during liver transplantation (LT). We investigated the protective role of insulin-induced gene 2 (Insig2) in steatotic liver's I/R injury and underlying mechanisms. Employing mouse model with Insig2 knock-out or hepatocyte-specific overexpression and high-fat diets to induce steatosis, we subjected these mice to hepatic I/R injury. The primary hepatocytes isolated from steatotic liver were used in in vitro hypoxia/reoxygenation (H/R) experiment. Our integrated in vivo and in vitro approach uncovered that Insig2 deficiency exacerbated steatotic liver's damage following hepatic I/R injury, whereas its overexpression offers protection. Mechanically, integrative analysis of transcriptome, proteome, and metabolome found that Insig2 deficiency disturbed lipid metabolism and oxidative stress homeostasis, particularly inhibiting GPX4 expression to induce ferroptosis. Furthermore, chemical inhibition of ferroptosis reversed the deleterious effect of Insig2 deficiency; whereas the protective influence of Insig2 overexpression was negated by the target inhibition of GPX4, leading to an exacerbation of hepatic I/R damage. These insights underscored the potential of the Insig2-GPX4 axis as a therapeutic target, presenting a novel avenue for enhancing the resilience of steatotic liver grafts against I/R injury.

The Asian Pacific association for the study of the liver clinical practice guidelines for the diagnosis and management of metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD) affects over one-fourth of the global adult population and is the leading cause of liver disease worldwide. To address this, the Asian Pacific Association for the Study of the Liver (APASL) has created clinical practice guidelines focused on MAFLD. The guidelines cover various aspects of the disease, such as its epidemiology, diagnosis, screening, assessment, and treatment. The guidelines aim to advance clinical practice, knowledge, and research on MAFLD, particularly in special groups. The guidelines are designed to advance clinical practice, to provide evidence-based recommendations to assist healthcare stakeholders in decision-making and to improve patient care and disease awareness. The guidelines take into account the burden of clinical management for the healthcare sector.

Pathogenic Mechanisms of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)-Associated Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third leading cause of cancer deaths worldwide. The etiology of HCC has now dramatically changed from viral hepatitis to metabolic dysfunction-associated steatotic liver disease (MASLD). The main pathogenesis of MASLD-related HCC is the hepatic lipid accumulation of hepatocytes, which causes chronic inflammation and the subsequent progression of hepatic fibrosis. Chronic hepatic inflammation generates oxidative stress and DNA damage in hepatocytes, which contribute to genomic instability, resulting in the development of HCC. Several metabolic and molecular pathways are also linked to chronic inflammation and HCC in MASLD. In particular, the MAPK and PI3K-Akt-mTOR pathways are upregulated in MASLD, promoting the survival and proliferation of HCC cells. In addition, MASLD has been reported to enhance the development of HCC in patients with chronic viral hepatitis infection. Although there is no approved medication for MASLD besides resmetirom in the USA, there are some preventive strategies for the onset and progression of HCC. Sodium-glucose cotransporter-2 (SGLT2) inhibitor, a class of medications, has been reported to exert anti-tumor effects on HCC by regulating metabolic reprogramming. Moreover, CD34-positive cell transplantation improves hepatic fibrosis by promoting intrahepatic angiogenesis and supplying various growth factors. Furthermore, exercise improves MASLD through an increase in energy consumption as well as changes in chemokines and myokines. In this review, we summarize the recent progress made in the pathogenic mechanisms of MASLD-associated HCC. Furthermore, we introduced new therapeutic strategies for preventing the development of HCC based on the pathogenesis of MASLD.

Role of the FOXM1/CMA/ER stress axis in regulating the progression of nonalcoholic steatohepatitis

BACKGROUND/AIMS

The molecular mechanisms driving nonalcoholic steatohepatitis (NASH) progression are poorly understood. This research examines the involvement of chaperone-mediated autophagy (CMA) in NASH progression.

METHODS

Hepatic CMA activity was analysed in NASH mice and patients. Lysosome-associated membrane protein 2A (LAMP2A) was knocked down or overexpressed to assess the effects of hepatocyte-specific CMA on NASH progression. Mice received a high-fat diet or a methionine and choline-deficient diet to induce NASH. Palmitic acid was employed to mimic lipotoxicity-induced hepatocyte damage in vitro. The promoter activity of FOXM1 was evaluated via ChIP and dual-luciferase reporter assays.

RESULTS

Hepatic CMA activity was substantially low in NASH mice and patients. LAMP2A knockdown resulted in hepatocyte-specific CMA deficiency, which promoted fibrosis and hepatic inflammation in NASH mice. Both in vitro and in vivo, CMA deficiency also exacerbated hepatocyte damage and endoplasmic reticulum (ER) stress. Mechanistically, CMA deficiency in hepatocytes increased cholesterol accumulation by blocking the degradation of 3-hydroxy-3-methylglutaryl coenzyme A (HMGCR), a key cholesterol synthesis-related enzyme, and the accumulated cholesterol subsequently induced ER stress and hepatocyte damage. The restoration of hepatocyte-specific CMA activity effectively ameliorated diet-induced NASH and ER stress in vivo and in vitro. FOXM1 directly bound to LAMP2A promoter and negatively regulated its transcription. The upregulation of FOXM1 expression impaired CMA and enhanced ER stress, which in turn increased FOXM1 expression, resulting in a vicious cycle and promoting NASH development.

CONCLUSIONS

This study highlights the significance of the FOXM1/CMA/ER stress axis in NASH progression and proposes novel therapeutic targets for NASH.

KEY POINTS

Chaperone-mediated autophagy (CMA) deficiency in hepatocytes promotes hepatic inflammation and fibrosis in mice with nonalcoholic steatohepatitis (NASH) by inducing cholesterol accumulation and endoplasmic reticulum (ER) stress. Upregulated FOXM1 impairs CMA by suppressing the transcription of lysosome-associated membrane protein 2A (LAMP2A), a rate-limiting component of CMA. ER stress increases FOXM1 expression and cholesterol accumulation. FOXM1/CMA/ER stress axis forms a vicious circle and promotes the development of NASH.

TM6SF2 -rs58542926 Genotype Has Opposing Effects on Incidence of Hepatic and Cardiac Events in a Community Cohort

INTRODUCTION

TM6SF2 -rs58542926-T is associated with increased cirrhosis and modestly decreased coronary artery disease prevalence. However, relative effects of TM6SF2 genotype on major adverse cardiovascular events (MACE) vs liver-related events (LRE) are not known.

METHODS

We used the UK Biobank, a prospective cohort with genetic and inpatient diagnosis data. The primary predictor was TM6SF2 -rs58542926 genotype, and the primary outcomes were MACE and LRE. Effects were reported as subhazard ratios (sHRs) and 10-year cumulative incidence by Fine-Gray competing risk analyses.

RESULTS

More than 430,000 individuals met inclusion criteria. TM6SF2 -rs58542926-TT genotype (vs CC) was associated with higher incidence of LRE (adjusted sHR 3.16, 95% confidence interval 1.86-5.37) and lower incidence of MACE (adjusted sHR for TT vs CC genotype 0.76, 95% confidence interval 0.63-0.91). In individuals with fibrosis-4 (FIB4) < 1.3, 1.3-2.67, and > 2.67, 10-year LRE incidence in TM6SF2 -rs58542926-TT vs CC individuals was 0.08% vs 0.06% ( P > 0.05), 0.81% vs 0.20% ( P < 0.0001), and 10.5% vs 3.4% ( P = 0.00094), respectively. The corresponding values for MACE were 3.8% vs 5.1% ( P = 0.032), 6.4% vs 8.2% ( P = 0.040), and 17.1% vs 12.4% ( P > 0.05). The absolute decrease in MACE with rs58542926-TT (vs CC) genotype exceeded the absolute increase in LRE in all groups but FIB4 > 2.67. Associations of TM6SF2 genotype with LRE/MACE were significant in men but not women. TM6SF2 -rs58542926-T allele was also associated with increased hepatic steatosis and corrected T1 time by magnetic resonance imaging, with greater effect sizes in men than women.

DISCUSSION

TM6SF2 genotype has opposite effects on LRE vs MACE incidence, and absolute effects on MACE were greater except in those with highest FIB4 scores. Effects were strongest in men. These findings clarify implications of TM6SF2 genotype based on personalized clinical risk.

Disease Progression for Histologic Diagnosis of Metabolic Dysfunction-Associated Steatotic Liver Disease in the Real-World: A Nationwide US Study

INTRODUCTION

We compared clinical characteristics and outcomes in real-world metabolic dysfunction-associated steatotic liver disease (MASLD) patients with or without liver biopsy using a nationwide cohort in United States (USA) to fill in gaps in selection of biopsy patients.

METHODS

We conducted a retrospective cohort study of adult MASLD patients using Marketscan® Databases (1/2007-12/2021). Patients were categorized into those with or without liver biopsy during follow-up.

RESULTS

We analyzed 540,326 MASLD patients: 23,732 with and 516,594 without biopsy. Only 4% of MASLD patients received liver biopsy and biopsy rate decreased in the last 5 years (9.4%-3.6%). After 1:5 propensity score matching on baseline characteristics including age, sex, and comorbidities, a total of 23,731 patients with biopsy and 118,396 matched patients without biopsy were analyzed. The incidence per 1,000 person-years for hepatocellular carcinoma (HCC) was 0.22 versus 2.18, cirrhosis 29.75 versus 90.44, and hepatic decompensation 15.84 versus 28.25 compared patients with and without biopsy. In multivariable analysis, patients with biopsy had more than 9 times higher risk of developing HCC, 3 times higher risk of cirrhosis, and 78% higher risk of hepatic decompensation. In subgroup analysis, the association remained consistent when stratified by age (<50 and ≥50), sex, and diabetes mellitus. Predictors of having biopsy included age, metabolic diseases, and living in North central or Northeast of USA.

CONCLUSION

These data can inform clinical patient management that biopsy patients likely represent a selected group at higher risk for disease progression, especially in clinical trials for MASLD therapies.

INTRODUCTION

We compared clinical characteristics and outcomes in real-world metabolic dysfunction-associated steatotic liver disease (MASLD) patients with or without liver biopsy using a nationwide cohort in United States (USA) to fill in gaps in selection of biopsy patients.

METHODS

We conducted a retrospective cohort study of adult MASLD patients using Marketscan® Databases (1/2007-12/2021). Patients were categorized into those with or without liver biopsy during follow-up.

RESULTS

We analyzed 540,326 MASLD patients: 23,732 with and 516,594 without biopsy. Only 4% of MASLD patients received liver biopsy and biopsy rate decreased in the last 5 years (9.4%-3.6%). After 1:5 propensity score matching on baseline characteristics including age, sex, and comorbidities, a total of 23,731 patients with biopsy and 118,396 matched patients without biopsy were analyzed. The incidence per 1,000 person-years for hepatocellular carcinoma (HCC) was 0.22 versus 2.18, cirrhosis 29.75 versus 90.44, and hepatic decompensation 15.84 versus 28.25 compared patients with and without biopsy. In multivariable analysis, patients with biopsy had more than 9 times higher risk of developing HCC, 3 times higher risk of cirrhosis, and 78% higher risk of hepatic decompensation. In subgroup analysis, the association remained consistent when stratified by age (<50 and ≥50), sex, and diabetes mellitus. Predictors of having biopsy included age, metabolic diseases, and living in North central or Northeast of USA.

CONCLUSION

These data can inform clinical patient management that biopsy patients likely represent a selected group at higher risk for disease progression, especially in clinical trials for MASLD therapies.

Natural history and progression of metabolic dysfunction-associated steatotic liver disease

The natural history of metabolic dysfunction-associated steatotic liver disease (MASLD), previously referred to as non-alcoholic fatty liver disease (NAFLD), is complex and long. A minority of patients develop inflammation and risk progressive fibrosis that can result in cirrhosis. Progression to cirrhosis occurs in 3-5% of patients and often takes more than 20 years. This narrative review presents an update on the natural history of MASLD, discussing studies and risk estimates for progression to severe outcomes, such as decompensated cirrhosis or hepatocellular carcinoma. We highlight the dynamic progression of liver damage, how to identify patients whose disease progresses over time, and how risk factors might be mitigated to reduce the risk for disease progression.

Transcriptomic Landscape Analysis Reveals a Persistent DNA Damage Response in Metabolic Dysfunction-associated Steatohepatitis Post-dietary Intervention

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) and its more advanced form, metabolic dysfunction-associated steatohepatitis, have emerged as the most prevalent liver diseases worldwide. Currently, lifestyle modification is the foremost guideline-recommended management strategy for MASLD. However, it remains unclear which detrimental signals persist in MASLD even after disease remission. Thus, we aimed to examine the persistent changes in liver transcriptomic profiles following this reversal.

METHODS

Male C57BL/6J mice were divided into three groups: Western diet (WD) feeding, chow diet (CD) feeding, or diet reversal from WD to CD. After 16 weeks of feeding, RNA sequencing was performed on the mice's livers to identify persistent alterations characteristic of MASLD. Additionally, RNA sequencing databases containing high-fat diet-fed P53-knockout mice and human MASLD samples were utilized.

RESULTS

WD-induced MASLD triggered persistent activation of the DNA damage response (DDR) and its primary transcription factor, P53, long after the resolution of the hepatic phenotype through dietary reversal. Elevated levels of P53 might promote apoptosis, thereby exacerbating metabolic dysfunction-associated steatohepatitis, as they strongly correlated with hepatocyte ballooning, an indicator of apoptosis activation. Moreover, P53 knockout in mice led to downregulated expression of apoptosis signaling in the liver. Mechanistically, P53 may regulate apoptosis by transcriptionally activating the expression of apoptosis-enhancing nuclease (AEN). Consistently, P53, AEN, and the apoptosis process all exhibited persistently elevated expression and showed a strong inter-correlation in the liver following dietary reversal.

CONCLUSIONS

The liver demonstrated upregulation of DDR signaling and the P53-AEN-apoptosis axis both during and after exposure to WD. Our findings provide new insights into the mechanisms of MASLD relapse, highlighting DDR signaling as a promising target to prevent MASLD recurrence.

Metabolic Dysfunction-Associated Steatotic Liver Disease in Patients with Inflammatory Bowel Diseases: A Pilot Study

BACKGROUND

Inflammatory bowel disease (IBD) is characterized by persistent inflammation and is often associated with metabolic dysfunction-associated steatotic liver disease (MASLD). IBD patients are at risk of developing MASLD due to shared risk factors such as gut dysbiosis and systemic inflammation. The new MASLD nomenclature emphasizes the link between liver steatosis and cardiometabolic comorbidities. However, the prevalence of MASLD in IBD patients remains poorly explored. The main aim of this cross-sectional study is to assess the prevalence of ultrasound (US) and the clinical features of MASLD in patients with IBDs.

MATERIALS AND METHODS

We conducted a retrospective study enrolling 272 Italian IBD patients attending Renato Dulbecco Teaching Hospital in a period between 1 January 2021 and 31 December 2023. MASLD was diagnosed based on the presence of liver steatosis with cardiometabolic risk factors, using established guidelines. Demographic, clinical, and laboratory data were collected and analyzed. Statistical significance was determined at a p-value < 0.05.

RESULTS

Of the 272 IBD patients, 6% had non-alcoholic fatty liver disease (NAFLD), while 18% had MASLD. Patients with IBD-MASLD were significantly older, had higher body mass index, waist circumference, and triglyceride levels, and were more likely to have type 2 diabetes mellitus and hypertension compared to those with IBD-NAFLD. IBD-MASLD patients also showed higher disease activity scores and required more frequent surgical interventions. Bivariate logistic regression revealed triglyceride levels as a significant predictor of MASLD in IBD patients.

CONCLUSIONS

MASLD is more prevalent in IBD patients, highlighting the importance of early detection of liver steatosis in this at-risk population. The association between MASLD and cardiometabolic risk factors underscores the need for a multidisciplinary approach to manage these patients effectively. Further studies in larger cohorts are necessary to confirm these findings and explore the pathophysiological mechanisms involved.

Review article: Hepatic steatosis and its associations with acute and chronic liver diseases

BACKGROUND

Hepatic steatosis is a common finding in liver histopathology and the hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), whose global prevalence is rising.

AIMS

To review the histopathology of hepatic steatosis and its mechanisms of development and to identify common and rare disease associations.

METHODS

We reviewed literature on the basic science of lipid droplet (LD) biology and clinical research on acute and chronic liver diseases associated with hepatic steatosis using the PubMed database.

RESULTS

A variety of genetic and environmental factors contribute to the development of chronic hepatic steatosis or steatotic liver disease, which typically appears macrovesicular. Microvesicular steatosis is associated with acute mitochondrial dysfunction and liver failure. Fat metabolic processes in hepatocytes whose dysregulation leads to the development of steatosis include secretion of lipoprotein particles, uptake of remnant lipoprotein particles or free fatty acids from blood, de novo lipogenesis, oxidation of fatty acids, lipolysis and lipophagy. Hepatic insulin resistance is a key feature of MASLD. Seipin is a polyfunctional protein that facilitates LD biogenesis. Assembly of hepatitis C virus takes place on LD surfaces. LDs make important, functional contact with the endoplasmic reticulum and other organelles.

CONCLUSIONS

Diverse liver pathologies are associated with hepatic steatosis, with MASLD being the most important contributor. The biogenesis and dynamics of LDs in hepatocytes are complex and warrant further investigation. Organellar interfaces permit co-regulation of lipid metabolism to match generation of potentially toxic lipid species with their LD depot storage.

Aspirin for Metabolic Dysfunction-Associated Steatotic Liver Disease Without Cirrhosis: A Randomized Clinical Trial

Importance

Aspirin may reduce severity of metabolic dysfunction-associated steatotic liver disease (MASLD) and lower the incidence of end-stage liver disease and hepatocellular carcinoma, in patients with MASLD. However, the effect of aspirin on MASLD is unknown.

Objective

To test whether low-dose aspirin reduces liver fat content, compared with placebo, in adults with MASLD.

Design, Setting, and Participants

This 6-month, phase 2, randomized, double-blind, placebo-controlled clinical trial was conducted at a single hospital in Boston, Massachusetts. Participants were aged 18 to 70 years with established MASLD without cirrhosis. Enrollment occurred between August 20, 2019, and July 19, 2022, with final follow-up on February 23, 2023.

Interventions

Participants were randomized (1:1) to receive either once-daily aspirin, 81 mg (n = 40) or identical placebo pills (n = 40) for 6 months.

Main Outcomes and Measures

The primary end point was mean absolute change in hepatic fat content, measured by proton magnetic resonance spectroscopy (MRS) at 6-month follow-up. The 4 key secondary outcomes included mean percentage change in hepatic fat content by MRS, the proportion achieving at least 30% reduction in hepatic fat, and the mean absolute and relative reductions in hepatic fat content, measured by magnetic resonance imaging proton density fat fraction (MRI-PDFF). Analyses adjusted for the baseline value of the corresponding outcome. Minimal clinically important differences for study outcomes were not prespecified.

Results

Among 80 randomized participants (mean age, 48 years; 44 [55%] women; mean hepatic fat content, 35% [indicating moderate steatosis]), 71 (89%) completed 6-month follow-up. The mean absolute change in hepatic fat content by MRS was -6.6% with aspirin vs 3.6% with placebo (difference, -10.2% [95% CI, -27.7% to -2.6%]; P = .009). Compared with placebo, aspirin treatment significantly reduced relative hepatic fat content (-8.8 vs 30.0 percentage points; mean difference, -38.8 percentage points [95% CI, -66.7 to -10.8]; P = .007), increased the proportion of patients with 30% or greater relative reduction in hepatic fat (42.5% vs 12.5%; mean difference, 30.0% [95% CI, 11.6% to 48.4%]; P = .006), reduced absolute hepatic fat content by MRI-PDFF (-2.7% vs 0.9%; mean difference, -3.7% [95% CI, -6.1% to -1.2%]; P = .004]), and reduced relative hepatic fat content by MRI-PDFF (-11.7 vs 15.7 percentage points; mean difference, -27.3 percentage points [95% CI, -45.2 to -9.4]; P = .003). Thirteen participants (32.5%) in each group experienced an adverse event, most commonly upper respiratory tract infections (10.0% in each group) or arthralgias (5.0% for aspirin vs 7.5% for placebo). One participant randomized to aspirin (2.5%) experienced drug-related heartburn.

Conclusions and Relevance

In this preliminary randomized clinical trial of patients with MASLD, 6 months of daily low-dose aspirin significantly reduced hepatic fat quantity compared with placebo. Further study in a larger sample size is necessary to confirm these findings.

Trial Registration

ClinicalTrials.gov Identifier: NCT04031729.