Fibrosis progression in nonalcoholic fatty liver vs nonalcoholic steatohepatitis: a systematic review and meta-analysis of paired-biopsy studies

LEADS - a comprehensive human liver-on-a-chip for non-alcoholic steatohepatitis (NASH) drug testing

Metabolic dysfunction associated steatohepatitis (MASH), also known as non-alcoholic steatohepatitis (NASH), is a progressive form of steatotic liver disease (SLD). It is an emerging healthcare threat due its high prevalence, accelerated and non-linear progression, and final culmination as decompensated liver failure and/or hepatocellular carcinoma (HCC). The pathogenesis of NASH is complex with strong ethnic influences and genetic predispositions, underscoring the need for preclinical models that utilize patient-derived cells to enhance our understanding of the disease. Current models face three major limitations: (i) reliance on primary cells with limited reproducibility, high cost, short culture duration and ethical considerations, (ii) failure to recapitulate all key features of NASH, and (iii) inadequate drug testing data and/or data did not correlate with clinical responses. Therefore, there is a pressing need for robust and relevant preclinical models that faithfully recapitulate human NASH, allow generation of patient-specific models and provide quantitative responses for mechanistic studies and drug testing. We have developed a functional liver tissue-on-a-chip by co-culturing human adult liver stem cell (haLSC)-derived hepatobiliary organoids, induced pluripotent stem cell (iPSC)-derived Kupffer cells (iKCs) and iPSC-derived hepatic stellate cells (iHSCs). We simulated the metabolic microenvironment of hyper nutrition and leaky gut by treating the cells with a concoction of free fatty acids (FFAs), fructose, gut-derived lipopolysaccharides (LPS) and a gut-derived metabolite, phenyl acetic acid (PAA). Through optimization of co-culture media and induction regimens, we were able to stably induce steatosis, hepatocellular ballooning, inflammation, and activation of iHSC and fibrosis-all key hallmarks of NASH. Our LEADS (liver-on-a-chip for NASH drug testing) model also recapitulated the pathological types of steatosis and allowed for quantification of the key features via microscopic evaluation and secretome profiling to score for disease severity. Notably, treatment with saroglitazar, pioglitazone, cenicriviroc (CVC), obeticholic acid (OCA) and resmetirom produced responses similar to those observed in clinical trials. Taken together, our LEADS model is the first model developed using patient-derived hepatic stem cells which recapitulated all key features used for comprehensive drug testing, with results matching to clinical responses.

Integrated liver-secreted and plasma proteomics identify a predictive model that stratifies MASH

Obesity is a major risk factor for metabolic-associated steatotic liver disease (MASLD), which can progress to metabolic-associated steatohepatitis (MASH). There are no validated non-invasive tests to stratify persons with obesity with a greater risk for MASH. Herein, we assess plasma and liver from 266 obese individuals spanning the MASLD spectrum. Ninety-six human livers were precision-cut, and mass spectrometry-based proteomics identifies 3,333 proteins in the liver-secretion medium, of which 107 are differentially secreted in MASH compared with no pathology. The plasma proteome is markedly remodeled in MASH but is not different between patients with steatosis and no pathology. The APASHA model, comprising plasma apolipoprotein F (APOF), proprotein convertase subtilisin/kexin type 9 (PCSK9), afamin (AFM), S100 calcium-binding protein A6 (S100A6), HbA1c, and zinc-alpha-2-glycoprotein (AZGP1), stratifies MASH (area under receiver operating characteristic [AUROC] = 0.88). Our investigations detail the evolution of liver-secreted and plasma proteins with MASLD progression, providing a rich resource defining human liver-secreted proteins and creating a predictive model to stratify patients with obesity at risk of MASH.

Volatomics for Diagnosis and Risk Stratification of MASLD: A Proof-Of-Concept Study

BACKGROUND AND AIMS

Human breath contains numerous volatile organic compounds (VOCs) produced by physiological and metabolic processes or perturbed in pathological states. Electronic nose (eNose) technology has been extensively validated as a non-invasive diagnostic tool for respiratory disease. Using eNose-derived exhaled breath signals, we investigated whether it could discriminate patients with metabolic dysfunction-associated steatotic liver disease (MASLD) from healthy volunteers and identify patients at high risk of disease progression.

METHODS

In a prospective single-centre study, exhaled breath VOCs were analysed using an eNose, in a well-characterised cohort comprising patients with Child-Turcotte-Pugh class A MASLD cirrhosis (n = 30), non-cirrhotic MASLD (n = 30) and healthy volunteers (n = 30). An unbiased machine learning clustering technique was applied. Longitudinal clinical data were collected over 5 years for the patient cohort. Logistic regression and univariable analysis were performed to identify risk factors for disease progression, liver-related outcomes, and all-cause mortality.

RESULTS

Principal component analysis of breath VOCs discriminated patients with MASLD from healthy volunteers with 100% sensitivity (p < 0.001, cross-validation verification of 96%), independent of age and gender. The eNose breath profile classified patients with MASLD into three distinct subgroups with similar baseline clinical and demographic characteristics but markedly different prognoses. During the 5-year follow-up period, Cluster 2 was identified as a higher-risk subgroup for progression (42%, p = 0.03), liver-related decompensation events (17%, p = 0.06), and all-cause mortality (12.5%).

CONCLUSION

eNose can discriminate patients with MASLD from healthy volunteers and, using unbiased clustering analysis, identify patients with a significantly worse prognosis. These results warrant prospective validation in independent MASLD populations.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02950610.

Bridging the gap in obesity research: A consensus statement from the European Society for Clinical Investigation

BACKGROUND

Most forms of obesity are associated with chronic diseases that remain a global public health challenge.

AIMS

Despite significant advancements in understanding its pathophysiology, effective management of obesity is hindered by the persistence of knowledge gaps in epidemiology, phenotypic heterogeneity and policy implementation.

MATERIALS AND METHODS

This consensus statement by the European Society for Clinical Investigation identifies eight critical areas requiring urgent attention. Key gaps include insufficient long-term data on obesity trends, the inadequacy of body mass index (BMI) as a sole diagnostic measure, and insufficient recognition of phenotypic diversity in obesity-related cardiometabolic risks. Moreover, the socio-economic drivers of obesity and its transition across phenotypes remain poorly understood.

RESULTS

The syndemic nature of obesity, exacerbated by globalization and environmental changes, necessitates a holistic approach integrating global frameworks and community-level interventions. This statement advocates for leveraging emerging technologies, such as artificial intelligence, to refine predictive models and address phenotypic variability. It underscores the importance of collaborative efforts among scientists, policymakers, and stakeholders to create tailored interventions and enduring policies.

DISCUSSION

The consensus highlights the need for harmonizing anthropometric and biochemical markers, fostering inclusive public health narratives and combating stigma associated with obesity. By addressing these gaps, this initiative aims to advance research, improve prevention strategies and optimize care delivery for people living with obesity.

CONCLUSION

This collaborative effort marks a decisive step towards mitigating the obesity epidemic and its profound impact on global health systems. Ultimately, obesity should be considered as being largely the consequence of a socio-economic model not compatible with optimal human health.

Liver cirrhosis in metabolic dysfunction-associated steatohepatitis

In the present narrative review, we have summarized the current evidence on the natural progression of metabolic dysfunction-associated steatohepatitis (MASH) cirrhosis observed through the placebo arm in clinical trials and observational studies. The outcomes scrutinized throughout our review were histology-related changes, non-invasive fibrosis markers, indicators of decompensation, end-stage hepatic complications, and mortality reported during the different clinical trials. Given the short duration of clinical trials, observational studies were included to obtain better insight into the long-term progression and prognosis of MASH cirrhosis. Lastly, new updates about MASH cirrhosis treatments were listed, and the results of these randomized clinical trials were described to enhance our understanding of our current standing in the treatment of MASH cirrhosis.

Global patterns of utilization of noninvasive tests for the clinical management of metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Noninvasive tests (NITs) are used to risk-stratify metabolic dysfunction-associated steatotic liver disease. The aim was to survey global patterns of real-world use of NITs.

METHODS

A 38-item survey was designed by the Global NASH Council. Providers were asked about risks for advanced fibrosis, which NITs (cutoff values) they use to risk-stratify liver disease, monitor progression, and which professional guidelines they follow.

RESULTS

A total of 321 participants from 43 countries completed the survey (54% hepatologists, 28% gastroenterologists, and 18% other). Of the respondents, 85% would risk-stratify patients with type 2 diabetes, obesity (82%), or abnormal liver enzymes (73%). Among NITs to rule out significant or advanced fibrosis, transient elastography (TE) and fibrosis-4 (FIB-4) were most used, followed by NAFLD Fibrosis Score, Enhanced Liver Fibrosis, and magnetic resonance elastography. The cutoffs for ruling out significant fibrosis varied considerably between practices and from guidelines, with only 50% using TE <8 kPa, 65% using FIB-4 <1.30 for age <65, and 41% using FIB-4 <2.00 for age ≥65. Similar variability was found for ruling in advanced fibrosis, where thresholds of FIB-4 ≥2.67 and TE ≥10 kPa were used by 20% and 17%, respectively. To establish advanced fibrosis, 48% would use 2 NITs while 23% would consider 1 NIT, and 17% would confirm with liver biopsy. TE was used by >75% to monitor, and 66% would monitor (intermediate or high risk) annually. Finally, 65% follow professional guideline recommendations regarding NITs.

CONCLUSIONS

In clinical practice, there is variability in NIT use and their thresholds. Additionally, there is suboptimal adherence to professional societies' guidelines.

A prospective comparison of two ultrasound attenuation imaging modes using different frequencies for assessing hepatic steatosis

PURPOSE

This study compared the diagnostic performance of two attenuation imaging (ATI) modes-low-frequency (3 MHz) and high-frequency (4 MHz)-for assessing hepatic steatosis, with histopathological hepatic fat fraction (HFF) as the reference standard.

METHODS

This prospective single-center study enrolled participants with suspected metabolic dysfunction-associated steatotic liver disease (MASLD) scheduled for liver biopsy or surgery between June 2023 and June 2024. Attenuation coefficient (AC) values were consecutively measured using low- and high-frequency ATI modes, while the skin-to-region of interest distance (SRD) was measured simultaneously. Spearman correlation analysis evaluated the relationships of AC with HFF and SRD, and linear regression identified factors affecting AC. Diagnostic performance was evaluated using the area under the receiver operating characteristic curve (AUROC).

RESULTS

In total, 119 participants (mean age, 37.2±12.0 years; 87 men) were included, with 73 (61.3%) diagnosed with MASLD. HFF ranged from 0% to 50%. The AC values in the lowfrequency mode were significantly higher than those in the high-frequency mode (0.61 vs. 0.54 dB/cm/MHz, P<0.001). HFF significantly influenced AC in both modes, whereas SRD affected AC only in the high-frequency mode (P<0.001). AC correlated positively with HFF in both modes (rs≥0.514, P<0.001) and negatively with SRD in the high-frequency mode (rs=-0.338, P<0.001). The AUROC for hepatic steatosis did not differ significantly between the two modes (0.751 vs. 0.771, P=0.609).

CONCLUSION

The low-frequency mode produced higher AC values than the high-frequency mode and demonstrated comparable diagnostic accuracy for assessing hepatic steatosis. Unlike the high-frequency mode, the low-frequency mode was not influenced by SRD.

Identification of growth differentiation factor 15 as an early predictive biomarker for metabolic dysfunction-associated steatohepatitis: A nested case-control study of UK Biobank proteomic data

AIMS

This study aims to determine the predictive capability for metabolic dysfunction-associated steatohepatitis (MASH) long before its diagnosis by using six previously identified diagnostic biomarkers for metabolic dysfunction-associated steatotic liver disease (MASLD) with proteomic data from the UK Biobank.

MATERIALS AND METHODS

A nested case-control study comprising a MASH group and three age- and sex-matched control groups (metabolic dysfunction-associated steatosis, viral hepatitis and normal liver controls) was conducted. Olink proteomics, anthropometric and biochemical data at baseline levels were obtained from the UK Biobank. The baseline levels of CDCP1, FABP4, FGF21, GDF15, IL-6 and THBS2 were analysed prospectively to determine their predictive accuracy for subsequent diagnosis with a mean lag time of over 10 years.

RESULTS

At baseline, GDF15 demonstrated the best performance for predicting MASH occurrence at 5 and 10 years later, with AUCs of 0.90 at 5 years and 0.86 at 10 years. A predictive model based on four biomarkers (GDF15, FGF21, IL-6 and THBS2) showed AUCs of 0.88 at both 5 and 10 years. Furthermore, a protein-clinical model that included these four circulating protein biomarkers along with three clinical factors (BMI, ALT and TC) yielded AUCs of 0.92 at 5 years and 0.89 at 10 years.

CONCLUSIONS

GDF15 at baseline levels outperformed other individual circulating protein biomarkers for the early prediction of MASH. Our data suggest that GDF15 and the GDF15-based model may be used as easy-to-implement tools to identify patients with high risks of developing MASH at a mean lag time of over 10 years.

Carboxylesterase 2A gene knockout or enzyme inhibition alleviates steatohepatitis in rats by regulating PPARγ and endoplasmic reticulum stress

Metabolic dysfunction associated steatotic liver disease (MASLD) is a widespread liver disease that progresses from simple steatosis to severe steatohepatitis stage. Despite the recognized importance of carboxylesterase 2 (CES2) in hepatic lipid metabolism, the role of CES2 in hepatic inflammation remains unclear. The rat genome encodes six Ces2 genes and Ces2a shows high expression in the liver and intestine. Lipid metabolism, inflammation, fibrosis, and endoplasmic reticulum (ER) stress were investigated in Ces2a knockout (KO) rats. KO rats showed spontaneous liver lipid accumulation due to increased lipogenesis and reduced fatty acid oxidation. Non-targeted lipidomic analysis revealed enhanced lysophosphatidylcholines (LPCs) and phosphatidylcholines (PCs) in KO rats and increased concentrations of ligands, thus activating the expression of PPARγ. Although there was simple lipid accumulation in the liver of KO rats, Ces2a deficiency showed a significant protective effect against LPS and diet-induced hepatic steatohepatitis by inhibiting ER stress regulated by PPARγ activation. In line with this, treatment with tanshinone IIA, a CES2 inhibitor, significantly alleviated the progression of steatohepatitis induced by the MCD diet. In conclusion, the increased PPARγ expression in Ces2a deficiency may counteract liver inflammation and ER stress despite the presence of simple steatosis. Therefore, CES2 inhibition represents a potential therapeutic approach for steatohepatitis.

Gene-based therapies for steatotic liver disease

Advances in nucleic acid delivery have positioned the liver as a key target for gene therapy, with adeno-associated virus vectors showing long-term effectiveness in treating hemophilia. Steatotic liver disease (SLD), the most common liver condition globally, primarily results from metabolic dysfunction-associated and alcohol-associated liver diseases. In some individuals, SLD progresses from simple steatosis to steatohepatitis, cirrhosis, and eventually hepatocellular carcinoma, driven by a complex interplay of genetic, metabolic, and environmental factors. Genetic variations in various lipid metabolism-related genes, such as patatin-like phospholipase domain-containing protein 3 (PNPLA3), 17β-hydroxysteroid dehydrogenase type 13 (HSD17B13), and mitochondrial amidoxime-reducing component 1 (MTARC1), impact the progression of SLD and offer promising therapeutic targets. This review largely focuses on genes identified through clinical association studies, as they are more likely to be effective and safe for therapeutic intervention. While preclinical research continues to deepen our understanding of genetic factors, early-stage clinical trials involving gene-based SLD therapies, including transient antisense and small-molecule approaches, are helping prioritize therapeutic targets. Meanwhile, hepatocyte gene editing technologies are advancing rapidly, offering alternatives to transient methods. As such, gene-based therapies show significant potential for preventing the progression of SLD and enhancing long-term liver health.

Metabolic Syndrome and Liver Disease: Re-Appraisal of Screening, Diagnosis, and Treatment Through the Paradigm Shift from NAFLD to MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), encompasses a spectrum of liver diseases characterized by hepatic steatosis, the presence of at least one cardiometabolic risk factor, and no other apparent cause. Metabolic syndrome (MetS) is a cluster of clinical conditions associated with increased risk of cardiovascular disease, type 2 diabetes, and overall morbidity and mortality. This narrative review summarizes the changes in the management of people with MetS and NAFLD/MASLD from screening to therapeutic strategies that have occurred in the last decades. Specifically, we underline the clinical importance of considering the different impacts of simple steatosis and advanced fibrosis and provide an up-to-date overview on non-invasive diagnostic tests (i.e., imaging and serum biomarkers), which now offer acceptable accuracy and are globally more accessible. Early detection of MetS and MASLD is a top priority as it allows for timely interventions, primarily through lifestyle modification. The liver and cardiovascular benefits of a global and multidimensional approach are not negligible. Therefore, a holistic approach to both conditions, MetS and related chronic liver disease, should be applied to improve overall health and longevity.

Treatment of IL-18-binding protein biologics suppresses fibrotic progression in metabolic dysfunction-associated steatohepatitis

Metabolic dysfunction-associated steatohepatitis (MASH) is a chronic liver disease characterized by inflammation and fibrosis, with enhanced interleukin-18 (IL-18) signaling. IL-18-binding protein (IL-18BP) neutralizes IL-18, but its therapeutic potential in MASH is unclear. We find elevated IL-18BP and IL-18 levels in patients with MASH and mice, with free IL-18 correlating with disease severity. IL-18 stimulates interferon-gamma (IFNγ) production in CD4 T cells, increasing hepatic IL-18BP. IL-18BP-deficient mice show worsened liver inflammation and fibrosis. We develop a human IL-18BP biologics (APB-R3) and inject it to mice to evaluate its pharmacologic efficacy. APB-R3 significantly improves MASH in reducing fibrosis and inflammation and inhibits hepatic stellate cell activation via the cGMP pathway. This study proposes that abrogation of IL-18 signaling by boosting IL-18BP can strongly inhibit the development of MASH-induced fibrosis, and our engineered IL-18BP biologics can become a promising therapeutic candidate for curing MASH.

Cardiometabolic risk factors and clinical course of liver cirrhosis

BACKGROUND

The global prevalence of Metabolic Dysfunction-Associated Liver Disease is dramatically increasing with the diffusion of cardiometabolic risk factors (CMRFs). The aim of the present study was to assess the natural course of liver cirrhosis, in terms of decompensation, development of hepatocellular carcinoma and mortality, in relation to the presence of CMRFs (type 2 diabetes mellitus, obesity, arterial hypertension, low HDL levels, hypertriglyceridemia).

PATIENTS

667 patients with liver cirrhosis (50 with CMRFs and without non-metabolic aetiological factors, 167 with non-metabolic aetiological factors and without CMRFs, and 450 with both non-metabolic aetiological factors and at least one CMRF) followed at the University and General Hospital of Padua, Italy, from 1998 to 2022, were included.

RESULTS

No difference in the occurrence of cirrhosis decompensating events and development of hepatocellular carcinoma was observed, whereas patients in the metabolic or mixed group had 4-3-fold higher all-cause mortality and significantly lower 3-years survival compared to patients in the non-metabolic group, despite a better liver function at enrolment. Hypertriglyceridemia and low HDL levels were the less prevalent CMRFs, but those associated with the highest risk of cirrhosis decompensation. Hypertriglyceridemia was also associated with an increased risk of mortality. Arterial hypertension was associated with a reduced risk of cirrhosis decompensation, but a higher risk of mortality.

CONCLUSION

Compared to patients without CMRFs, those with CMRFs had similar rates of liver cirrhosis decompensation but higher overall mortality. Hypertriglyceridemia was associated with a high risk of both liver decompensation and death.

A Markov Model Unveiling the Impact of Resmetirom on the Natural History of MASLD Patients: A Sistematic Review and Meta-Analysis

BACKGROUND AND AIM

The MAESTRO-NASH phase 3 trial reported that a 52-week treatment of Resmetirom is effective in improving fibrosis and metabolic dysfunction-associated steatohepatitis (MASH) in patients with MASH and F2 or F3 fibrosis, while data on the impact on 5-year and long-term clinical outcomes are still lacking. We simulated the transition probabilities of disease progression in MASLD patients with F2 or F3 fibrosis and the effect of Resmetirom treatment on clinical outcomes.

METHODS

A meta-analysis of literature data formed transition matrices for fibrosis stages and complications, defined as compensated (CC) and decompensated cirrhosis (DC), hepatocellular carcinoma (HCC) and mortality-liver-related mortality (LR-M), cardiovascular mortality (CV-M) and extra-hepatic cancer mortality (EHC-M). Markov model was developed to depict the F2 and F3 fibrosis stage progression towards the complications and to evaluate the effect of Resmetirom treatment on the natural history of MASLD.

RESULTS

We estimated the 5-year probability of Resmetirom-treated and untreated MASLD patients with baseline F2 fibrosis of developing CC (5.16% vs. 6.82%, respectively), DC (0.25% vs. 0.3%, respectively), HCC (0.25% vs. 0.32%, respectively) and mortality (0.15% vs. 0.16% for LR-M; 1.02% vs. 1.1% for CV-M; 1.07% vs. 1.2% for EHC-M, respectively). Similarly, we estimated the five-year probability of Resmetirom-treated and untreated MASLD patients with baseline F3 fibrosis of developing CC (17.12% vs. 21.34%, respectively), DC(1.1% vs. 1.47%, respectively), HCC (1.21% vs. 1.73%, respectively) and mortality (0.59% vs. 0.91% for LR-M, 1.92% vs. 2.14% for CV-M and 1.04% vs. 1.14% for EHC-M, respectively). Life Years Gained (LYG) of Resmetirom-treated patients were 0.45 and 0.63 in MASLD patients with F2 and F3 fibrosis, respectively, and the model was sensitive to changes in Resmetirom efficacy and transition probabilities.

CONCLUSIONS

Resmetirom decreases the 5-year and lifetime Markov-model estimated risk of CC, DC, HCC and liver-related mortality in patients with MASLD and F2 or F3 fibrosis.

Reliability of an Expanded Non-alcoholic Steatohepatitis Grading and Staging System for Assessment of Disease Activity and Fibrosis

The nonalcoholic steatohepatitis clinical research network (NASH-CRN) system is commonly used for histologic assessment of disease activity and fibrosis in NASH. Despite this, the system does not fully capture the range of disease activity and fibrosis. As such, an expanded NAS (E-NAS) grading and staging system with a calculated E-NAS index was developed by our group. In this follow up study, we aim to revalidate the E-NAS system and compare its reliability to existing systems. Hematoxylin and eosin and trichrome stained sections from 40 liver biopsies were reviewed digitally by four hepatopathologists and assessed using the NASH-CRN and E-NAS systems as well as a modified Ishak fibrosis stage. The pathologist's gestalt impression of disease activity and fibrosis was scored on a Visual Analogue Scale (VAS), which ranged from 0 (no activity/fibrosis) to 100 (the worst activity/fibrosis ever seen). Inter-rater reliability was assessed, and Spearman correlation coefficients were calculated. The E-NAS index had higher inter-rater agreement versus the NAS score (ICC 0.70 vs 0.61). The inter-rater agreement for ballooning in the E-NAS system was also higher at 0.67 compared to the NAS (ICC 0.60). ICCs for fibrosis were comparable between all the systems assessed (0.78 to 0.88). Finally, the calculated E-NAS index was higher with increasing stage of fibrosis compared to the NAS suggesting that it associates better with fibrosis. In summary, the E-NAS system demonstrates substantial inter-rater reliability as well as improved correlation with disease activity VAS and fibrosis compared to the NAS score.

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.

Accuracy of Non-Invasive Imaging Techniques for the Diagnosis of MASH in Patients With MASLD: A Systematic Review

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing public health problem. The secondary stage in MASLD is steatohepatitis (MASH), the co-existence of steatosis and inflammation, a leading cause of progression to fibrosis and mortality. MASH resolution alone improves survival. Currently, MASH diagnosis is via liver biopsy. This study sought to evaluate the accuracy of imaging-based tests for MASH diagnosis, which offer a non-invasive method of diagnosis.

METHODS

Eight academic literature databases were searched and references of previous systematic reviews and included papers were checked for additional papers. Liver biopsy was used for reference standard.

RESULTS

We report on 69 imaging-based studies. There were 31 studies on MRI, 27 on ultrasound, five on CT, 13 on transient elastography, eight on controlled attenuation parameter (CAP) and two on scintigraphy. The pathological definition of MASH was inconsistent, making it difficult to compare studies. 55/69 studies (79.71%) were deemed high-risk of bias as they had no preset thresholds and no validation. The two largest groups of imaging papers were on MRI and ultrasound. AUROCs were up to 0.93 for MRE, 0.90 for MRI, 1.0 for magnetic resonance spectroscopy (MRS) and 0.94 for ultrasound-based studies.

CONCLUSIONS

Our study found that the most promising imaging tools are MRI techniques or ultrasound-based scores and confirmed there is potential to utilise these for MASH diagnosis. However, many publications are single studies without independent prospective validation. Without this, there is no clear imaging tool or score currently available that is reliably tested to diagnose MASH.

Metabolic dysfunction and alcohol-related liver disease (MetALD): Position statement by an expert panel on alcohol-related liver disease

In this position statement, we explore the intricate relationship between alcohol intake and metabolic dysfunction in the context of the 2023 nomenclature update for steatotic liver disease (SLD). Recent and lifetime alcohol use should be accurately assessed in all patients with SLD to facilitate classification of alcohol use in grams of alcohol per week. Alcohol biomarkers (i.e., phosphatidylethanol), use of validated questionnaires (i.e. AUDIT-C [alcohol use disorders identification test consumption]), and collateral information from friends and relatives could help facilitate differentiation between alcohol-related liver disease (ALD) per se and liver disease with both metabolic and alcohol-related components (MetALD). Heavy alcohol use can contribute to cardiometabolic risk factors such as high blood pressure, hypertriglyceridaemia, and hyperglycaemia. As a result, caution should be exercised in the application of only one metabolic dysfunction criterion to diagnose MASLD, as suggested in the 2023 nomenclature document, particularly in individuals exceeding weekly alcohol use thresholds of 140 g for women and 210 g for men. This is particularly important in those individuals with isolated high blood pressure, hypertriglyceridaemia, or hyperglycaemia, where the disease process may be driven by alcohol itself. Additionally, metabolic dysfunction and alcohol use should be reassessed over time, especially after periods of change in risk factor exposure. This approach could ensure a more accurate prognosis and effective management of SLD, addressing both metabolic and alcohol-related factors.

Exploring the potential of large language models in identifying metabolic dysfunction-associated steatotic liver disease: A comparative study of non-invasive tests and artificial intelligence-generated responses

BACKGROUND AND AIMS

This study sought to assess the capabilities of large language models (LLMs) in identifying clinically significant metabolic dysfunction-associated steatotic liver disease (MASLD).

METHODS

We included individuals from NHANES 2017-2018. The validity and reliability of MASLD diagnosis by GPT-3.5 and GPT-4 were quantitatively examined and compared with those of the Fatty Liver Index (FLI) and United States FLI (USFLI). A receiver operating characteristic curve was conducted to assess the accuracy of MASLD diagnosis via different scoring systems. Additionally, GPT-4V's potential in clinical diagnosis using ultrasound images from MASLD patients was evaluated to provide assessments of LLM capabilities in both textual and visual data interpretation.

RESULTS

GPT-4 demonstrated comparable performance in MASLD diagnosis to FLI and USFLI with the AUROC values of .831 (95% CI .796-.867), .817 (95% CI .797-.837) and .827 (95% CI .807-.848), respectively. GPT-4 exhibited a trend of enhanced accuracy, clinical relevance and efficiency compared to GPT-3.5 based on clinician evaluation. Additionally, Pearson's r values between GPT-4 and FLI, as well as USFLI, were .718 and .695, respectively, indicating robust and moderate correlations. Moreover, GPT-4V showed potential in understanding characteristics from hepatic ultrasound imaging but exhibited limited interpretive accuracy in diagnosing MASLD compared to skilled radiologists.

CONCLUSIONS

GPT-4 achieved performance comparable to traditional risk scores in diagnosing MASLD and exhibited improved convenience, versatility and the capacity to offer user-friendly outputs. The integration of GPT-4V highlights the capacities of LLMs in handling both textual and visual medical data, reinforcing their expansive utility in healthcare practice.

Reducing complications of metabolic dysfunction-associated steatotic liver disease

INTRODUCTION

Complications from metabolic dysfunction-associated steatotic liver disease (MASLD) include liver-related and extrahepatic complications, and the all-cause mortality rate is significantly higher in patients with MASLD than in those without MASLD.

AREAS COVERED

We review the complications of MASLD and their management based on the European Association for the Study of the Liver (EASL) and American Association for the Study of Liver Diseases (AASLD) guidelines as well as medical papers. For the papers, we focused on studies referenced in the EASL and AASLD guidelines. Additionally, a search was conducted in PubMed to gather relevant literature.

EXPERT OPINION

Identifying and managing MASLD early, before it progresses to cirrhosis, is crucial to reducing mortality rates, and collaboration among healthcare professionals, including dietitians, nurses, and physical therapists, is vital for comprehensive management. There is active development of new drugs for MASLD, and we hope that new treatments will be developed soon.

Association of Components of Metabolic Syndrome and the Progression of Nonalcoholic Fatty Liver Disease

INTRODUCTION

The effects of metabolic syndrome (MetS), its individual components, and baseline liver histology, on the rates of progression and regression of nonalcoholic fatty liver disease (NAFLD), were evaluated.

METHODS

We conducted a post hoc analysis of a multicenter prospective cohort study using the noninterventional registry of the Nonalcoholic Steatohepatitis Clinical Research Network (2002-2022). We included patients aged 18 years or older with biopsy-proven NAFLD. Outcomes included progression/regression of histology defined by changes in NAFLD Activity Score, nonalcoholic steatohepatitis, or fibrosis. Crude incidence rates were compared among patients with MetS vs those without using Kaplan-Meier curves and log-rank test. Cox proportional hazard models were used to estimate effects of MetS and its components on the fibrosis progression/regression.

RESULTS

We included 452 patients; the mean age was 51 years, one-third was male, and 85% was White. The median follow-up was 4.3 (range: 1-15.6) years. At baseline, patients with MetS, large waist circumference, and impaired glucose tolerance/diabetes had worse ballooning and fibrosis scores and a higher prevalence of definite nonalcoholic steatohepatitis than those without. MetS was not associated with fibrosis progression or regression. Impaired glucose tolerance/diabetes was associated with a higher risk of fibrosis progression (adjusted hazard ratio = 1.61; 95% confidence interval: 1.11-2.34) whereas hypertension was associated with a lower risk (adjusted hazard ratio = 0.64; 95% confidence interval: 0.43-0.96).

DISCUSSION

In the cohort of patients with NAFLD, MetS was associated with greater histological severity at baseline but was not a risk factor of disease progression or regression. Impaired glucose/diabetes was associated with a higher rate and hypertension with a lower rate of fibrosis progression.

Concordance of vibration-controlled transient elastography and magnetic resonance elastography for fibrosis staging in patients with metabolic dysfunction-associated steatotic liver disease

OBJECTIVES

To evaluate the concordance between vibration-controlled transient elastography (VCTE) and magnetic resonance elastography (MRE) for staging liver fibrosis and assessing hypothetical eligibility for resmetirom treatment in a cohort of patients with metabolic dysfunction-associated steatotic liver disease (MASLD). A secondary objective was to assess the performance of VCTE for liver fat quantification.

MATERIALS AND METHODS

This retrospective study included 103 patients (61 males; mean age 54.7 years) with suspected MASLD who underwent VCTE and MRI/MRE. The following parameters were extracted: liver stiffness (LS) from both techniques, controlled attenuation parameter (CAP) from VCTE, and MRI-proton density fat fraction (PDFF). Agreement and fibrosis stage distributions were assessed using Cohen's Kappa and McNemar's tests. ROC analysis assessed the performance of CAP against MRI-PDFF (considered the reference for steatosis).

RESULTS

A significant difference was observed in assigned fibrosis stage distributions between VCTE and MRE across all combinations (F0-F1 vs F2-F4, F0-F2 vs F3-F4, F0-F3 vs F4, all p < 0.001) with fair to moderate agreement between modalities (Cohen's Kappa values 0.305-0.554). VCTE assigned a higher fibrosis stage in 42 patients (40.7%). Thirty-three vs eighteen patients were classified as F2-F3 (qualified for resmetirom treatment) with VCTE vs MRE (Cohen's Kappa 0.215), which was associated with estimated cost savings of $707,701/year with MRE. VCTE-CAP achieved AUCs of 0.547, 0.754, and 0.813 for diagnosing mild, moderate, and severe steatosis, respectively.

CONCLUSION

VCTE and MRE have fair to moderate agreement for fibrosis staging, with VCTE tending to assign a higher fibrosis stage compared to MRE. VCTE-CAP reliably detects only severe steatosis.

KEY POINTS

Question What is the agreement between VCTE and MRE in staging fibrosis in MASLD and identifying patients with F2-F3 disease? Findings Limited concordance was found between VCTE and MRE for staging liver fibrosis and identifying F2-F3 disease; VCTE tended to assign higher fibrosis stages compared to MRE. Clinical relevance MRE could represent the modality of choice for selecting patients with metabolic dysfunction-associated steatohepatitis for resmetirom therapy as it potentially offers high cost-savings compared to VCTE.

Validation of the diagnostic accuracy of the acFibroMASH index for at-risk MASH in patients with metabolic dysfunction-associated steatotic liver disease

OBJECTIVE

The objective of this study was to validate the diagnostic accuracy of the acFibroMASH index in a population of metabolic dysfunction-associated steatotic liver disease (MASLD) patients with at-risk metabolic dysfunction-associated steatohepatitis (MASH) and to compare it with other scoring systems.

METHODS

394 patients with biopsy-proven MASLD were retrospectively enrolled. The patients were divided into the at-risk MASH (NAFLD activity score ≥ 4 and significant fibrosis) group (n = 103) and the non-at-risk MASH group (n = 291). The diagnostic performance of the acFibroMASH index was compared to that of fibroScan-aspartate aminotransferase (FAST) and other noninvasive fibrosis scores by plotting the receiver operating characteristic curve (ROC), including the area under the curve (AUC), sensitivity, and specificity. Cut-offs of the acFibroMASH index for sensitivity (≥ 0.90) and specificity (≥ 0.90) were obtained in our cohort.

RESULTS

The AUC of the acFibroMASH index in assessing at-risk MASH was 0.780, while the AUC of FAST was 0.770. The comparison of acFibroMASH with FAST showed no significant difference (P = 0.542). When the cut-off value for acFibroMASH was < 0.15, 95.5% of at-risk MASH patients could be excluded in 89 patients correctly. Conversely, when the cut-off value was set at > 0.39, 49.3% of at-risk MASH patients could be diagnosed in 140 patients correctly. When the NPV was set at 0.900, the critical value for exclusion was determined to be 0.23, with a sensitivity of 0.835 and a specificity of 0.526.

CONCLUSION

This study validated the efficacy of the acFibroMASH index in predicting at-risk MASH in a population of MASLD patients, demonstrating comparable performance to that of the FAST. The acFibroMASH index may provide a valuable clinical basis for screening and identifying at-risk MASH in primary care settings.

Fluorofenidone attenuates choline-deficient, l-amino acid-defined, high-fat diet-induced metabolic dysfunction-associated steatohepatitis in mice

Metabolic dysfunction-associated steatohepatitis (MASH), a severe form of metabolic dysfunction-associated steatotic liver disease (MASLD), involves hepatic lipid accumulation, inflammation, and fibrosis. It can progress to cirrhosis or hepatocellular carcinoma without timely treatment. Current treatment options for MASH are limited. This study explores the therapeutic effects of fluorofenidone (AKF-PD), a novel small-molecule compound with antifibrotic and anti-inflammatory properties, on MASH in mouse model. Mice fed a choline-deficient, l-amino acid-defined, high-fat diet (CDAHFD) were treated with AKF-PD, resulting in reduced serum ALT, AST, hepatic lipid accumulation, liver inflammation, and fibrosis. Network pharmacology and RNA-sequencing analyses suggested that AKF-PD influenced multiple metabolic, inflammatory, and fibrosis-related pathways. Further experiments verified that AKF-PD activated hepatic AMPK signaling, leading to the inhibition of the downstream SREBF1/SCD1 pathway and the activation of autophagy. Additionally, AKF-PD suppressed the expression of various inflammatory factors, reduced macrophage infiltration, and inhibited NLRP3 inflammasome activation. Moreover, AKF-PD attenuated liver fibrosis by inhibiting TGFβ1/SMAD signaling. In conclusion, this study reveals that AKF-PD effectively decreases hepatic lipid accumulation, liver inflammation and fibrosis in a CDAHFD-induced MASH model, positioning AKF-PD as a promising candidate for the treatment of MASH.

From "Burnt-Out" to "Burning-Out": Capturing Liver Fat Loss in Patients With Advanced Metabolic Dysfunction-Associated Steatotic Liver Disease From a Dynamic Perspective

BACKGROUND AND AIMS

The absence of hepatic fat in advanced fibrosis has been documented in metabolic dysfunction-associated steatotic liver disease (''burnt-out" MASLD). However, whether hepatic fat loss occurs continuously with fibrosis progression is controversial. We proposed a "burning-out" concept to describe this process and analyze the long-term outcomes of "burnt-out" and "burning-out" MASLD.

METHODS

We included a MASLD cohort from 16 centers, including 3273 individuals with baseline histology and 5455 with serial vibration-controlled transient elastography measurements during the follow-up. "Burnt-out" MASLD was defined by steatosis grade ≤S1 and fibrosis stage ≥F3. Trajectory analysis identified "burning-out" patients with continuous trends of decreasing controlled attenuation parameter and increasing liver stiffness measurement values.

RESULTS

Of 3273 patients with histologic evaluation included, 435 had "burnt-out" MASLD. Compared with those with pronounced steatosis in advanced fibrosis, patients with "burnt-out" had higher risks of all-cause mortality (hazard ratio [HR], 2.14; 95% confidence interval [CI], 1.14-4.02), liver-related events (LREs; HR, 1.77; 95% CI, 1.12-2.78), and hepatic decompensation (HR, 1.83; 95% CI, 1.11-3.01). Of 5455 patients with vibration-controlled transient elastography included for trajectory analysis, 176 were identified as "burning-out" MASLD. The incidence rates of all-cause mortality, LREs, and decompensation were 7.28, 26.47, and 21.92 per 1000 person-years in "burning-out" patients, respectively. The "burning-out" group had higher cumulative incidences of adverse outcomes than patients with consistently high controlled attenuation parameter and moderate/low liver stiffness measurement values (P < .0001).

CONCLUSIONS

Continuous hepatic fat loss accompanied by fibrosis progression, referred to as "burning-out," was observed in advanced MASLD and associated with high rates of all-cause mortality, LREs, and hepatic decompensation.

Updated recommendations for the management of metabolic dysfunction-associated steatotic liver disease (MASLD) by the Latin American working group

Metabolic dysfunction-associated steatotic liver disease (MASLD) is one of the leading causes of chronic liver disease globally. Based on the 2023 definition, MASLD is characterized by the presence of metabolic dysfunction and limited alcohol consumption (<140 grams/week for women, <210 grams/week for men). Given the significant burden of MASLD in Latin America, this guidance was developed by the Latin American Association for the Study of the Liver (ALEH) Working Group to address key aspects of its clinical assessment and therapeutic strategies. In Latin America, ultrasonography is recommended as the initial screening tool for hepatic steatosis due to its accessibility, while Fibrosis-4 (FIB-4) is preferred for fibrosis risk stratification, with further evaluation using more specific techniques (i.e., vibration-controlled transient elastography or Enhanced Liver Fibrosis [ELF] test). A Mediterranean diet is advised for all MASLD patients, with a target of 7-10% weight loss for those with excess weight. Complete alcohol abstinence is recommended for patients with significant fibrosis, and smoking cessation is encouraged regardless of fibrosis stage. Pharmacological options should be tailored based on the presence of steatohepatitis, liver fibrosis, excess weight, and diabetes, including resmetirom, incretin-based therapies, pioglitazone, and sodium-glucose cotransporter-2 inhibitors. Bariatric surgery may be considered for MASLD patients with obesity unresponsive to lifestyle and medical interventions. Hepatocellular carcinoma screening is advised for all cirrhotic patients, with consideration given to those with advanced fibrosis based on individual risk. Finally, routine cardiovascular risk assessment and proper diabetes prevention and management remain crucial for all patients with MASLD.

Roles of extracellular vesicles from different origins in metabolic-associated fatty liver disease: progress and perspectives

Metabolic-Associated Fatty Liver Disease (MAFLD) is the most common chronic liver disease worldwide, associated with systemic metabolic dysregulation. It can progress from simple hepatic steatosis (MAFL) to more severe conditions like Metabolic-Associated Steatohepatitis (MASH), fibrosis, cirrhosis, and Hepatocellular Carcinoma (HCC). There is a critical lack of reliable non-invasive diagnostic methods and effective pharmaceutical treatments for MAFLD/MASH, emphasizing the need for further research. Extracellular vesicles (EVs) are nanoscale structures that play important roles in cell signaling by delivering bioactive molecules. However, there is a significant gap in literature regarding the roles of EVs from hosts, plants, and microbiota in MAFLD. This review explores the potential of EVs from various sources-host, plants, and microbiota-as biomarkers, therapeutic agents, drug carriers, and treatment targets for MAFLD. Firstly, the roles of host-derived extracellular vesicles (EVs) in MAFLD, with a focus on cell-type specific EVs and their components-proteins, miRNAs, and lipids-for disease diagnosis and monitoring were discussed. Moreover, it highlighted the therapeutic potential of mesenchymal stem cell (MSC)-derived EVs in reducing lipid accumulation and liver injury, and immune cell-derived EVs in mitigating inflammation and fibrosis. The review also discussed the use of host-derived EVs as drug carriers and therapeutic targets due to their ability to deliver bioactive molecules that impact disease mechanisms. Additionally, it summarized research on plant-derived EVs, which help reduce liver lipid accumulation, inflammation, and enhance gut barrier function in MAFLD. Also, the review explored microbial-derived EVs as novel therapeutic targets, particularly in relation to insulin resistance, liver inflammation, and dysfunction in MAFLD. Overall, by exploring the diverse roles of EVs from host, plant, and microbiota sources in MAFLD, this review offers valuable insights into their potential as non-invasive biomarkers and novel therapeutic strategies, which could pave the way for more effective diagnostic and treatment options for this increasingly prevalent liver disease. Notably, the challenges of translating EVs into clinical practice were also thoroughly discussed, aiming to provide possible directions and strategies for future research.

Clinical Guidelines of the Russian Society for the Study of the Liver, Russian Gastroenterological Association, Russian Society for the Prevention of Non-Communicable Diseases, Russian Association of Endocrinologists, Russian Scientific Medical Society of Therapists, National Society of Preventive Cardiology, Russian Association of Gerontologists and Geriatricians on Non-Alcoholic Fatty Liver Disease

Aim. The clinical guidelines are intended to provide information support for making decisions by gastroenterologists, general practitioners and internists that will improve the quality of medical care for patients with non-alcoholic fatty liver disease, taking into account the latest clinical data and principles of evidence-based medicine. Key points. Clinical guidelines contain information about current views on etiology, risk factors and pathogenesis of nonalcoholic fatty liver disease, peculiarities of its clinical course. Also given recommendations provide information on current methods of laboratory and instrumental diagnostics, invasive and non-invasive tools for nonalcoholic fatty liver disease and its clinical phenotypes assessment, approaches to its treatment, considering the presence of comorbidities, features of dispensary monitoring and prophylaxis. The information is illustrated with algorithms of differential diagnosis and physician's actions. In addition, there is information for the patient and criteria for assessing the quality of medical care. Conclusion. Awareness of specialists in the issues of diagnosis, treatment and follow-up of patients with nonalcoholic fatty liver disease contributes to the timely diagnosis and initiation of treatment, which in the long term will significantly affect their prognosis and quality of life.

Metabolic dysfunction-associated steatotic liver disease in adults

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

Untargeted lipidomic analysis of metabolic dysfunction-associated steatohepatitis in women with morbid obesity

Metabolic Dysfunction-Associated Steatohepatitis (MASH) represents the severe condition of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD). Currently, there is a need to identify non-invasive biomarkers for an accurate diagnosis of MASH. Previously, omics studies identified alterations in lipid metabolites involved in MASLD. However, these studies require validation in other cohorts. In this sense, our aim was to perform lipidomics to identify the circulating lipid metabolite profile of MASH. We assessed a liquid chromatography coupled to a mass spectrometer-based untargeted lipidomic assay in serum samples of 216 women with morbid obesity that were stratified according to their hepatic diagnosis into Normal Liver (NL, n =  44), Simple Steatosis (SS, n =  66) and MASH (n =  106). First, we identified a profile of lipid metabolites that are increased in MASLD, composed of ceramides, triacylglycerols (TAG) and some phospholipids. Then, we identified that patients with SS have a characteristic profile of increased levels of ceramides, diacylglycerols DG (36:2) and DG (36:4), some TAG and a few phospholipids such as PC (32:1), PE (38:3), PE (40:6), PI (32:0) and PI (32:1). Later, in MASH patients, we found increased levels of ceramides, deoxycholic acid, a set of TAG, and some phospholipids such as PC, PE, PI and LPI; while we found decreased levels of the DG (36:0). Finally, we have reported a panel of lipid metabolites that might be used to differentiate patients with MASH from SS patients, made up of increased levels of 9-HODE some PC and PE, the LPI (16:0) and decreased levels of DG (36:0). To conclude, our investigation has suggested a lipid metabolite profile associated with MASLD and MASH. Specifically, a set of lipid metabolites seems to be discriminatory in MASH subjects compared to SS individuals. Thus, this panel of lipid metabolites could be used as a non-invasive diagnostic tool.

Effect of therapeutic lifestyle changes on patients with overweight/obesity and non-alcoholic fatty liver disease: A randomized controlled trial

BACKGROUND

Non-alcoholic fatty liver disease is a liver condition that is increasing globally. Unfortunately, there are no successful or approved pharmacological treatments for non-alcoholic fatty liver disease. Hence, this study aimed to investigate the effect of therapeutic lifestyle changes on patients with overweight/obesity and non-alcoholic fatty liver disease.

METHODS

A prospective, parallel-group, randomized controlled trial was conducted. The patients were randomized into intervention and control groups using tables with random numbers. In the control group, routine health guidance was provided for 3 months, while in the intervention group, diversified lifestyle intervention was provided. The body composition, visceral fat area, abdominal circumference, and body mass index of the control and intervention groups were compared before and after the intervention. Descriptive statistics, paired t-tests, and linear regression models were used for data analysis.

RESULTS

A total of 115 participants (57 in the intervention group and 58 in the control group) completed the study. The intervention groups had significantly greater high-density lipoprotein cholesterol levels, basal metabolic rate, muscle mass, and questionnaire scores than the control groups (P < 0.05). Furthermore, the intervention participants had lower body mass index, abdominal circumference, triglyceride levels, low-density lipoprotein cholesterol levels, and fatty liver index (P < 0.05).

CONCLUSIONS

Therapeutic lifestyle changes therapy for non-alcoholic fatty liver disease patients with overweight/obesity can significantly control body mass index, improve blood lipid levels, reduce fatty liver and body fat rates, improve basic metabolism, alleviate disease, and improve quality of life. More research is needed to determine the long-term impact of therapeutic lifestyle changes in high-risk groups.

Therapeutic landscape of metabolic dysfunction-associated steatohepatitis (MASH)

Metabolic dysfunction-associated steatotic liver disease (MASLD) and its severe subgroup metabolic dysfunction-associated steatohepatitis (MASH) have become a global epidemic and are driven by chronic overnutrition and multiple genetic susceptibility factors. The physiological outcomes include hepatocyte death, liver inflammation and cirrhosis. The first therapeutic for MASLD and MASH, resmetirom, has recently been approved for clinical use and has energized this therapeutic space. However, there is still much to learn in clinical studies of MASH, such as the scale of placebo responses, optimal trial end points, the time required for fibrosis reversal and side effect profiles. This Review introduces aspects of disease pathogenesis related to drug development and discusses two main therapeutic approaches. Thyroid hormone receptor-β agonists, such as resmetirom, as well as fatty acid synthase inhibitors, target the liver and enable it to function within a toxic metabolic environment. In parallel, incretin analogues such as semaglutide improve metabolism, allowing the liver to self-regulate and reversing many aspects of MASH. We also discuss how combinations of therapeutics could potentially be used to treat patients.

Impact of PNPLA3 I148M on Clinical Outcomes in Patients With MASLD

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a heterogenous clinical and histopathological entity, where multiple metabolic co-factors are intertwined with high interindividual variability. The impact and severity of each factor (including obesity and type 2 diabetes) define a systemic dysmetabolism that can lead to either advanced liver disease and its complication (including hepatocellular carcinoma and clinical events related to portal hypertension) or extrahepatic events: incident cardiovascular disease, chronic kidney disease and extrahepatic cancers. The balance between environmental factors and genetic susceptibility has unique implications in MASLD: the intermittent injury of metabolic co-factors, their fluctuation over time and their specific management, are counterbalanced by the presence of gene variants that can significantly impact the disease at multiple levels. The I148M variant in the PNPLA3 gene is the most investigated genetic susceptibility that induces a more severe steatohepatitis, enhanced fibrogenesis and can shape the incidence of long-term clinical events regardless of, or worsened by, other metabolic risk factors.

METHODS AND RESULTS

In this review, we will summarise the updated evidence on the natural history of MASLD accounting for classical metabolic risk factors, the role of PNPLA3 in clinical sub-phenotyping (e.g., 'lean MASLD'), impact on disease severity and fibrosis progression, as well as its role for prognostication, alone or in combination with non-invasive tools into polygenic risk scores.

Macronutrient Modulation in Metabolic Dysfunction-Associated Steatotic Liver Disease-the Molecular Role of Fatty Acids compared with Sugars in Human Metabolism and Disease Progression

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a significant public health concern, with its progression to metabolic dysfunction-associated steatohepatitis (MASH) and fibrosis leading to severe outcomes including cirrhosis, hepatocellular carcinoma, and liver failure. Whereas obesity and excess energy intake are well-established contributors to the development and progression of MASLD, the distinct role of specific macronutrients is less clear. This review examines the mechanistic pathways through which dietary fatty acids and sugars contribute to the development of hepatic inflammation and fibrosis, offering a nuanced understanding of their respective roles in MASLD progression. In terms of addressing potential therapeutic options, human intervention studies that investigate whether modifying the intake of dietary fats and carbohydrates affects MASLD progression are reviewed. By integrating this evidence, this review seeks to bridge the gap in the understanding between the mechanisms of macronutrient-driven MASLD progression and the effect of altering the intake of these nutrients in the clinical setting and presents a foundation for future research into targeted dietary strategies for the treatment of the disease.

Pharmacological treatment for metabolic dysfunction-associated steatotic liver disease and related disorders: Current and emerging therapeutic options

Metabolic dysfunction-associated steatotic liver disease (MASLD; formerly known as nonalcoholic fatty liver disease) is a chronic liver disease affecting over a billion individuals worldwide. MASLD can gradually develop into more severe liver pathologies, including metabolic dysfunction-associated steatohepatitis (MASH), cirrhosis, and liver malignancy. Notably, although being a global health problem, there are very limited therapeutic options against MASLD and its related diseases. While a thyroid hormone receptor agonist (resmetirom) is recently approved for MASH treatment, other efforts to control these diseases remain unsatisfactory. Given the projected rise in MASLD and MASH incidence, it is urgent to develop novel and effective therapeutic strategies against these prevalent liver diseases. In this article, the pathogenic mechanisms of MASLD and MASH, including insulin resistance, dysregulated nuclear receptor signaling, and genetic risk factors (eg, patatin-like phospholipase domain-containing 3 and hydroxysteroid 17-β dehydrogenase-13), are introduced. Various therapeutic interventions against MASH are then explored, including approved medication (resmetirom), drugs that are currently in clinical trials (eg, glucagon-like peptide 1 receptor agonist, fibroblast growth factor 21 analog, and PPAR agonist), and those failed in previous trials (eg, obeticholic acid and stearoyl-CoA desaturase 1 antagonist). Moreover, given that the role of gut microbes in MASLD is increasingly acknowledged, alterations in the gut microbiota and microbial mechanisms in MASLD development are elucidated. Therapeutic approaches that target the gut microbiota (eg, dietary intervention and probiotics) against MASLD and related diseases are further explored. With better understanding of the multifaceted pathogenic mechanisms, the development of innovative therapeutics that target the root causes of MASLD and MASH is greatly facilitated. The possibility of alleviating MASH and achieving better patient outcomes is within reach. SIGNIFICANCE STATEMENT: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide, and it can progress to more severe pathologies, including steatohepatitis, cirrhosis, and liver cancer. Better understanding of the pathogenic mechanisms of these diseases has facilitated the development of innovative therapeutic strategies. Moreover, increasing evidence has illustrated the crucial role of gut microbiota in the pathogenesis of MASLD and related diseases. It may be clinically feasible to target gut microbes to alleviate MASLD in the future.

Resmetirom and Thyroid Hormone Receptor‐Targeted Treatment for Metabolic Dysfunction‐Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction‐associated steatotic liver disease (MASLD) is a rapidly increasing chronic disease worldwide, particularly among patients with type 2 diabetes. Its severe form, metabolic dysfunction‐associated steatohepatitis (MASH), is also on the rise. The treatment of MASLD and MASH poses significant challenges. Thyroid hormones and their receptors thyroid hormone receptor (TR) agonists, especially resmetirom, have shown potential in improving metabolism and reducing liver inflammation. Thyroid hormones play a crucial role in regulating metabolism and maintaining physiological balance. However, in patients with MASLD, there is a reduced conversion of 3,3′,5,5′‐tetraiodo‐l‐thyronine (T4) to biologically active 3,5,3′‐triiodo‐l‐thyronine (T3), resulting in decreased T3 levels and impaired hepatic TR signaling. This hormonal imbalance is associated with disrupted hepatic lipid metabolism. Resmetirom, an oral selective TR agonist that specifically targets hepatocytes, was approved by the Food and Drug Administration (FDA) in March 2024 for the treatment of moderate to severe liver fibrosis in non‐cirrhotic adults with MASH. This approval was based on the results of the MAESTRO clinical program, which includes multiple‐stage research designs such as the MAESTRO‐NASH, MAESTRO‐NAFLD‐1, MAESTRO‐NAFLD‐OLE, and MAESTRO‐NASH‐OUTCOMES, aims to evaluate the efficacy and safety of resmetirom in different populations of MASH patient. Although the approval of resmetirom represents a significant milestone in the treatment of MAFLD and MASH, many questions remain regarding its long‐term effectiveness and impact on clinical outcomes. Ongoing research, particularly through the MAESTRO program, holds promise for providing additional insights into the long‐term management of MASLD using resmetirom and other similar medications.

Quantitative analysis of sterol balance in a mouse model of hepatic lipid accumulation induced by cholesterol and cholic acid supplementation

The cholesterol balance and bile acid metabolism in a mouse model of hepatic lipid accumulation induced by a diet supplemented with cholesterol and cholic acid (CA) were quantitatively evaluated. The mice were fed diets supplemented with different levels of cholesterol (0, 3, or 6 g/kg of diet) and CA (0.5 g/kg of diet) for 6 weeks. Cholesterol supplementation doubled the hepatic triglyceride concentration, regardless of the supplementation level, without inflammation or gallstone formation. Both cholesterol supplementations enhanced fecal excretion of muricholic acid. Additionally, the higher cholesterol supplementation led to an increase in fecal cholesterol excretion, accompanied by elevated expression of hepatic cholesterol exporters and a reduction in fecal bile acid excretion. In this mouse study, supplementation with 3 g cholesterol/kg diet and 0.5 g CA/kg diet was sufficient to induce hepatic lipid accumulation.

Relationship between dietary inflammatory index and metabolic dysfunction associated steatotic liver disease in children

Emerging research suggests a connection between dietary habits and metabolic dysfunction associated steatotic liver disease (MASLD). We aimed to assess the relationship between the Dietary Inflammatory Index (DII) and the severity of MASLD. This cross-sectional study involved 125 participants aged 7-18 with MASLD. Dietary intakes were assessed using a validated 147-item food frequency questionnaire. The DII was applied to measure diet-induced inflammation, categorizing diets into anti-inflammatory (DII < -1) and inflammatory diets (DII > + 1). To evaluate hepatic steatosis and fibrosis, transabdominal ultrasonography and the fibrosis-4 (FIB-4) index were utilized. After adjusting for potential confounding factors, individuals on inflammatory diets exhibited a significantly higher odds ratio (OR) for experiencing more severe steatosis (OR: 4.11; 95% CI: 1.08-15.71) compared to those on anti-inflammatory diets. Furthermore, each unit increase in DII scores was linked to a 2.6-fold increase in the odds of more severe steatosis (OR: 2.61; 95% CI: 1.28-5.32) and a 0.006 increase in FIB-4 scores (β: 0.006; 95% CI: 0.003-0.011). In conclusion, modifying dietary intakes to lower DII scores may be a beneficial approach to improving clinical outcomes in pediatric MASLD, as anti-inflammatory diets are associated with reduced severity of hepatic steatosis and fibrosis.

Diagnosis and Staging of Metabolic Dysfunction-Associated Steatotic Liver Disease Using Biomarker-Directed Aptamer Panels

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects one-third of adults globally. Despite efforts to develop non-invasive diagnostic tools, liver biopsy remains the gold standard for diagnosing metabolic dysfunction-associated steatohepatitis (MASH) and assessing fibrosis. This study investigated RNA aptamer panels, selected using APTASHAPE technology, for non-invasive MASLD diagnosis and fibrosis stratification. Aptamer panels were selected in a cohort of individuals with MASLD (development cohort, n = 77) and tested in separate cohorts: one with MASLD (test cohort, n = 57) and one assessed for bariatric surgery (bariatric cohort, n = 62). A panel distinguishing MASLD without steatohepatitis from MASH accurately stratified individuals in the developmentcohort (AUC = 0.83) but failed in the test and bariatric cohorts. It did, however, distinguish healthy controls from individuals with MASLD, achieving an AUC of 0.72 in the test cohort. A panel for fibrosis stratification differentiated F0 from F3-4 fibrosis in the development cohort (AUC = 0.68) but not in other cohorts. Mass spectrometry identified five plasma proteins as potential targets of the discriminative aptamers, with complement factor H suggested as a novel MASLD biomarker. In conclusion, APTASHAPE shows promise as a non-invasive tool for diagnosing and staging MASLD and identifying associated plasma biomarkers.

Association of MASLD Phenotypes With Liver Fibrosis in Hepatitis C: The Role of Cardiometabolic Risk Factors

Steatotic liver disease is prevalent among people with hepatitis C virus (HCV). The new definition of metabolic dysfunction-associated steatotic liver disease (MASLD) emphasises the metabolic drivers of steatosis and recognises its frequent coexistence with other chronic liver diseases, including HCV. We aimed to evaluate the association of coexisting MASLD and HCV with liver fibrosis. Individuals with HCV who underwent transient elastography (TE) with associated controlled attenuation parameter (CAP) were included from two clinical centres. MASLD and significant liver fibrosis were defined as the presence of steatosis (CAP ≥ 275 dB/m) with at least one cardiometabolic risk factor, and liver stiffness measurement (LSM) ≥ 7.1 kPa measured by TE, respectively. Associated cofactors of significant liver fibrosis were determined using stepwise regression and cross-validation by LASSO models to select confounders. Among 590 participants, 31% were diagnosed with MASLD. The prevalence of significant liver fibrosis was the highest among people with MASLD (58%) followed by HCV-related steatosis (45%) and the non-steatosis group (39%). After adjusting for potential confounders, MASLD was associated with significant liver fibrosis (adjusted odds ratio [aOR] 2.29, 95% confidence interval [CI] 1.07-4.87). Furthermore, specific MASLD phenotypes including diabetes, hypertension and overweight were associated with significant liver fibrosis, with aORs of 4.76 (95% CI 2.16-10.49), 3.44 (95% CI 1.77-6.68) and 2.54 (95% CI 1.27-5.07), respectively. In conclusion, MASLD is associated with liver fibrosis in people with HCV, specifically the diabetes, overweight and hypertensive phenotypes. Beyond pursuing a virological cure, healthcare providers should prioritise managing metabolic conditions, particularly diabetes, hypertension and obesity.

Understanding MASH: An Examination of Progression and Clinical Outcomes by Disease Severity in the TARGET-NASH Database

INTRODUCTION

Metabolic dysfunction-associated steatohepatitis (MASH), the progressive form of metabolic dysfunction-associated steatotic liver disease (MASLD), is linked to cardiometabolic risk factors such as obesity and type 2 diabetes (T2D). The rising prevalence of MASH and risk of hepatic and extra-hepatic complications emphasize the need for a better understanding of disease progression and associated outcomes. This study aimed to evaluate the incidence of, and demographic and clinical characteristics associated with, progression to MASH-related complications by disease severity in patients with non-cirrhotic MASH or MASH cirrhosis. Alignment between noninvasive tests (NITs) and biopsy-determined fibrosis stage was also assessed.

METHODS

This analysis used data from the TARGET-NASH cohort that includes adults with MASH across academic and community sites in the United States. Patients with non-cirrhotic MASH or MASH cirrhosis were stratified by disease severity based on fibrosis stage or cirrhosis. Progression to MASH-related outcomes, including all-cause mortality, cirrhosis, and liver transplantation, was assessed.

RESULTS

Among the 2378 patients included in this analysis, 48% had MASH cirrhosis. Incidence of all-cause mortality increased with disease severity from 0.14/100 person-months (100PM) at fibrosis stage 0-1 (F0-F1) to 2.02/100PM with compensated cirrhosis and 4.62/100PM with decompensated cirrhosis. Compared with patients with F0-F1, risk of progression to cirrhosis was higher in patients with F3 [hazard ratio (HR), 95% confidence interval (CI); 18.66, 10.97-31.73] and F2 (HR, 95% CI; 3.74, 2.00-6.98). Among those who progressed to MASH-related outcomes, 67.9% had T2D and 73.9% had hypertension. Vibration-controlled transient elastography showed better alignment with biopsy-determined fibrosis stage than Fibrosis-4 Index (FIB-4).

CONCLUSIONS

Progression to all-cause mortality in patients with MASH was significantly associated with the presence of higher fibrosis stage and cirrhosis. Cardiometabolic comorbidities such as T2D and hypertension were prevalent in patients with MASH progression. Early identification and management of MASH may mitigate disease progression and liver-related complications.

Accuracy of Controlled Attenuation Parameter for Liver Steatosis in High-Risk Patients for MASLD Using MRI-Proton Density Fat Fraction as Reference Standard

AIM

Controlled attenuation parameter (CAP) enables the noninvasive diagnosis of liver steatosis. Magnetic resonance imaging proton density fat fraction (MRI-PDFF) is increasingly used over biopsy for the assessment of steatosis in patients at risk for metabolic dysfunction-associated steatotic liver disease (MASLD). We assessed the accuracy of CAP for liver steatosis defined as MRI-PDFF ≥ 5%.

METHODS

We performed a cross-sectional, diagnostic accuracy study. We prospectively recruited consecutive adult participants with type 2 diabetes and body mass index (BMI) ≥ 25 kg/m2, who underwent CAP and MRI-PDFF within two weeks.

RESULTS

We included 113 participants. The area under the receiver operating characteristic (AUROC) of CAP for MRI-PDFF ≥ 5% was 0.82 [95% confidence interval (CI) 0.74-0.89]. CAP thresholds for ruling-out (sensitivity > 90%) and ruling-in (specificity > 90%) liver steatosis were below 249 and over 328 dB/m respectively. The AUROC of CAP for the detection of MRI-PDFF ≥ 10% was 0.81 (0.73-0.88). CAP thresholds for ruling-out and ruling-in MRI-PDFF ≥ 10% were below 271 and over 345 dB/m respectively. CAP measurements with an interquartile range (IQR) < 30 dB/m improved the detection of higher steatosis grades.

CONCLUSION

CAP has acceptable accuracy for diagnosing MRI-PDFF defined steatosis. Values below 249 dB/m can be used to rule-out liver steatosis, while values over 328 dB/m can set the diagnosis. An IQR < 30 dB/m might improve the accuracy of CAP for higher steatosis grades.

CLINICAL TRIAL REGISTRATION

Not applicable.

EUS-guided shear wave elastography for fibrosis screening in patients with obesity and metabolic dysfunction-associated steatotic liver disease: a pilot study (with video)

BACKGROUND AND AIMS

Liver fibrosis staging is challenging in patients with obesity and metabolic dysfunction-associated steatotic liver disease (MASLD). Liver biopsies are invasive, whereas noninvasive tests such as vibration-controlled transient elastography (VCTE) can be inaccurate in patients with obesity. We hypothesized that EUS-guided shear wave elastography (EUS-SWE) is more accurate for liver fibrosis staging in patients with MASLD and obesity; the aim of this pilot study was to test this hypothesis and establish optimal fibrosis stage cutoffs for EUS-SWE.

METHODS

This was a multicenter, cross-sectional study from prospectively collected data. Consecutive patients who underwent EUS-SWE with subsequent liver biopsy were included. EUS-SWE was compared with Fibrosis-4 Index (FIB-4) and VCTE. Area under the receiver-operating characteristic (AUROC) curve analysis was performed, and 90% sensitivity and specific cutoffs were calculated to determine optimal cutoffs.

RESULTS

Sixty-two patients were included. Mean body mass index was 40.74 kg/m2. EUS-SWE was superior to FIB-4 in discriminating significant fibrosis (F2; AUROC, .87 vs .61; P < .0048) and advanced fibrosis (F3; AUROC, .93 vs .63; P < .0001), but not cirrhosis (F4; AUROC, .95 vs .81; P = .099). EUS-SWE was superior to VCTE in predicting advanced fibrosis and cirrhosis (P = .0067 and P = .0022, respectively). The 90% sensitivity cutoffs for EUS-SWE were 7.50, 8.48, and 11.30 for F2, F3, and F4, and the 90% specificity cutoffs were 9.82, 10.20, and 14.60.

CONCLUSIONS

In this pilot study, EUS-SWE was superior to FIB-4 and VCTE for liver fibrosis staging in patients with MASLD and obesity. (Clinical trial registration number: NCT05728697.).

Delicate and thin fibrous septa indicate a regression tendency in metabolic dysfunction-associated steatohepatitis patients with advanced fibrosis

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatohepatitis (MASH)-related fibrosis is reversible. However, the dynamic morphology change in fibrosis regression remains unclear. We aim to explore the morphological characteristics of fibrosis regression in advanced MASH patients.

METHODS

Clinical and histological data of 79 biopsy-proved MASH patients with advanced fibrosis (F3-F4) were reviewed. The second harmonic generation/two-photon excitation fluorescence (SHG/TPEF) image technology was used to quantitatively identify the R (regressive) septa from P (progressive) septa and PS (perisinusoidal) fibrosis. Non-invasive tests were used to compare the fibrosis level with and without R septa groups. Transcriptomics was used to explore hub genes and the underlying mechanism of the formation of R septa.

RESULTS

The R septa were different from the P septa and PS fibrosis in detail collagen quantitation identified by SHG/TPEF technology. The R septa were found in MASH fibrosis-regressed patients, which met the definition of the "Beijing classification". Therefore, patients were divided into two groups according to septa morphology: with R septa (n = 10, 12.7%), and without R septa (n = 69, 87.3%). Patients with R septa had lower values in most non-invasive tests, especially for liver stiffness assessed by TE (12.3 vs. 19.4 kPa, p = 0.010) and FAST (FibroScan®-AST) score (0.43 vs. 0.70, p = 0.003). Transcriptomics analysis showed that the expressions of five hub fibrogenic genes, including Col3A1, BGN, Col4A1, THBS2, and Col4A2 in the R septa group, were significantly lower.

CONCLUSIONS

The R septa can be differentiated from the P septa and PS fibrosis by quantitative assessment of SHG/TPEF, and it represents a tendency of fibrosis regression in MASH patients.

TRIAL REGISTRATION

NCT03386890, 29/12/2017.

Moving diagnosis of liver fibrosis into the community

Chronic liver disease (CLD) is a leading cause of death worldwide, with alcohol consumption and metabolic risk factors accounting for the majority of cases of CLD in many developed countries. Currently, specific strategies for the early diagnosis of CLD are lacking and consequently most cases are diagnosed at an advanced stage, which is associated with negative consequences for disease management and prognosis. Screening for CLD is based on either detection of chronic viral hepatitis B and C, or detection of liver fibrosis in patients with steatotic liver disease related to alcohol or metabolic dysfunction. Non-invasive tools, including serological and imaging-based tests, can be used to detect liver fibrosis. Clinical practice guidelines recommend screening for liver fibrosis using algorithms that combine different non-invasive tests, with widely available but low accuracy tests, such as FIB-4, recommended as a first screening step in the primary care setting, and other tests with lower availability but higher accuracy, such as transient elastography or the enhanced liver fibrosis test, recommended as a second step. There are different pathways for early detection of patients with CLD from primary to specialised care, with primary care providers being key for early detection, management and referral of patients. In addition, interventions targeting metabolic risk factors and alcohol consumption should be carried out in collaboration between specialists and primary care. In this review, we describe liver fibrosis from the community perspective, highlighting gaps in knowledge on how to define the optimal combination of tests, target population, the ideal pathway of care for CLD, and how to increase implementation of programmes for early diagnosis of liver diseases in clinical practice.

Prevalence of advanced hepatic fibrosis and individualization of associated risk factors by Bayesian analysis in MASLD patients in French cardio-metabolic health networks

The aim of this study was to determine the prevalence of advanced hepatic fibrosis and to individualize using Bayesian analysis its associated risk factors in patients with metabolic dysfunction-associated steatotic liver disease (MASLD) being cared for in three Alsatian cardio-metabolic health networks in the North East of France. Overall, 712 patients aged ≥18 years with a female predominance were included into a prospective, cross-sectional, and observational study. Advanced fibrosis and severe steatosis were evaluated using transient elastography (FibroScan®). The proportion of MASLD patients was 80% and 84% in women and men (difference -4.2% [-10.0; 1.9]), respectively. Advanced fibrosis was observed in 11% of patients, being more common in men (16.9%) than women (7.5%) (difference 9.4 [4.3-15.0]). Severe steatosis was also more common in men (74.9%) than women (63.4%) (difference 11.4 [4.2-18.2]). Only three of the tested variables were likely associated with advanced fibrosis: gender (OR: 1.78 [1.17-2.68]; Pr [OR >1] = 1), T2DM (OR: 1.54 [1-2.37]; Pr [OR >1] = 0.97) and hypertriglyceridemia (OR: 1.49 [0.97-2.27]; Pr (OR >1) = 0.97). In conclusion, this study confirmed the usefulness of assessing hepatic fibrosis in patients with metabolic dysfunction. Therefore, access to FibroScan® should be facilitated in all cardio-metabolic health networks.