Preparing for the NASH Epidemic: A Call to Action

Metabolic dysfunction-associated steatotic liver disease and pregnancy

Metabolic dysfunction-associated steatotic liver disease (MASLD) is rising among reproductive-aged individuals and in pregnancy. MASLD in pregnancy does increase such risks as gestational diabetes, preeclampsia, and preterm birth. Although routine screening for MASLD has not been established in pregnancy, individuals with metabolic comorbidities, such as type 2 diabetes mellitus, should be evaluated by liver imaging and liver panel. Preconception counseling should address potential risks as well as need for optimized metabolic health before and during pregnancy. Fibrosis assessment should ideally be completed before pregnancy, to identify cases of cirrhosis that may warrant additional preconception management, such as variceal screening, as well as comanagement with maternal-fetal medicine specialists. In patients with MASLD, aspirin is advised at 12 weeks of gestational age to lower preeclampsia risk. In the absence of cirrhosis, no additional blood test monitoring is needed. In the general population, breastfeeding has beneficial effects on metabolic health in birthing parents and offspring and thus should be encouraged in the setting of MASLD, including access to enhanced lactation support. Research needs include evaluation of the long-term risks of MASLD in pregnancy on metabolic health in birthing parents and infants, as well as safety data for MASLD-directed therapies during pregnancy and lactation.

Multiple machine learning algorithms identify 13 types of cell death-critical genes in large and multiple non-alcoholic steatohepatitis cohorts

BACKGROUND

Dysregulated programmed cell death pathways mechanistically contribute to hepatic inflammation and fibrogenesis in non-alcoholic steatohepatitis (NASH). Identification of cell death genes may offer insights into diagnostic and therapeutic strategies for NASH.

METHODS

Data from multiple NASH cohorts were integrated, and 12 machine learning algorithms were applied to identify key dysregulated cell death-related genes and develop a binary classification model for NASH. Spearman's rank correlation coefficients quantified associations between these genes and clinical markers, immune infiltration profiles, and signature genes encoding pro-inflammatory mediators, metabolic regulators, and fibrotic drivers. Gene set enrichment analysis (GSEA) was performed to delineate the mechanistic underpinnings of these key genes. Consensus clustering analysis was then used to stratify patients with NASH into distinct phenotypic subgroups based on expression levels of these genes.

RESULTS

A NASH prediction model, developed using the random forest (RF) algorithm, demonstrated high diagnostic accuracy across multiple cohorts. Four key genes, enriched in lipid metabolism and inflammation pathways, were identified. Their transcriptional levels were significantly correlated with the non-alcoholic fatty liver disease activity score (NAS), hepatic inflammatory infiltration, molecular signatures of metabolic dysregulation (lipid homeostasis regulators), and fibrosis progression. These genes also enabled accurate classification of patients with NASH into clusters reflecting varying disease severity.

CONCLUSIONS

A binary classification model, developed using the RF algorithm, accurately identified patients with NASH. The four cell death genes, identified through 12 machine learning algorithms, represent potential biomarkers and therapeutic targets for NASH. These genes contribute to inflammation-related immune cell activation, lipid metabolism dysregulation, and liver fibrosis, highlighting the complex interplay between cell death and NASH progression.

Effectiveness of a Model of Care Based on Fibrosis-4 and Liver Stiffness Measurement for the Screening of Patients With Type 2 Diabetes Mellitus at Risk of Advanced Liver Disease: Results From an Italian Prospective Multicenter Study

INTRODUCTION

Patients with type 2 diabetes mellitus (T2DM) are at increased risk of metabolic dysfunction-associated steatotic liver disease, advanced liver fibrosis, and metabolic dysfunction-associated steatohepatitis (MASH). We evaluated the prevalence and severity of metabolic dysfunction-associated steatotic liver disease among patients with T2DM at their first referral to diabetes clinics and assessed the effectiveness of the 2-tier screening approach by Fibrosis-4 (FIB-4) and vibration-controlled transient elastography (VCTE).

METHODS

Consecutive patients with T2DM from 6 different diabetes clinics were prospectively enrolled. Liver stiffness measurement (LSM) was assessed by VCTE, whereas liver steatosis by controlled attenuation parameter (Fibroscan, Echosens, France). "At-risk MASH" was assessed by FibroScan-aspartate aminotransferase score.

RESULTS

Eight hundred patients (median age: 59, 53-65 years; males: 485, 60.6%) met the inclusion criteria. Prevalence of liver steatosis (controlled attenuation parameter ≥ 248 db/m) was 73.6%. The proportion of patients at medium/high risk of advanced liver fibrosis (LSM ≥ 8.0 kPa) was 16.9%. Patients with "at-risk MASH" (FibroScan-aspartate aminotransferase > 0.67) were 12.0%. A 2-tier screening for advanced liver fibrosis by FIB-4 and VCTE would have led to 70 patients (8.8%) referred to liver clinics with a false-negative rate of 9.6% (n = 77; patients with FIB-4 < 1.3 and LSM ≥ 8.0 kPa). At multivariate analysis, overweight/obesity (odds ratio = 3.13, 95% confidence interval 1.23-7.97) and elevated alanine aminotransferase (odds ratio = 1.91, 95% confidence interval 1.17-3.10) were independently associated with LSM ≥ 8.0 kPa in patients with FIB-4 < 1.3.

DISCUSSION

In diabetes clinics, the 2-tier screening using FIB-4 and VCTE is effective for the identification of patients with T2DM to be referred to hepatologists. VCTE referral may be considered for patients with overweight/obesity and elevated alanine aminotransferase classified as at low risk of advanced liver fibrosis by FIB-4.

Safety and efficacy of resmetirom in metabolic dysfunction-associated steatohepatitis (MASH): a systematic review and meta-analysis

Metabolic dysfunction-associated steatohepatitis (MASH) affects nearly 38% of the population, potentially progressing to cirrhosis and cancer. Lifestyle changes remain the cornerstone of management, but adherence is challenging, prompting the exploration of therapeutic options. Resmetirom, targeting thyroid hormone receptors, regulates liver enzymes and fat metabolism, showing potential as a treatment for MASH. This systematic review and meta-analysis evaluates the safety of resmetirom in MASH patients. Three randomized controlled trials with adult participants were analyzed, sourced from PubMed and the Cochrane Library until April 2024. Participants received either resmetirom or placebo, and data on adverse effects and efficacy outcomes were extracted. Statistical analyses, including risk ratios (RRs) and confidence intervals (CI), were performed using Review Manager (version 5.4.1) with a random-effects model. The pooled RR for serious adverse events was 0.85 (95% CI: 0.63-1.14; P  = 0.28), indicating no significant difference. However, diarrhea (RR = 1.82, 95% CI: 1.41-2.35; P  < 0.001) and nausea (RR = 1.73, 95% CI: 1.31-2.28; P  < 0.001) showed higher incidence. No significant differences were found for fatigue (RR = 1.19, 95% CI: 0.77-1.84; P  = 0.43) or urinary tract infections (RR = 1.07, 95% CI: 0.76-1.52; P  = 0.69). Liver fat content, lipid profiles, and liver enzymes also showed significant improvement in the resmetirom group. Low heterogeneity across most outcomes indicated consistent findings among the studies. While resmetirom demonstrates efficacy in improving lipid and liver profiles, its increased risk of diarrhea and nausea should be considered in therapeutic decisions.

Noninvasive identification of metabolic dysfunction-associated steatohepatitis (INFORM MASH): a retrospective cohort and disease modeling study

BACKGROUND

Using common clinical parameters, we aimed to noninvasively identify and predict metabolic dysfunction-associated steatohepatitis (MASH)/MASH with clinically significant fibrosis.

RESEARCH DESIGN AND METHODS

Patients aged ≥18 with electronic health record (EHR) documented liver function tests and liver biopsies between 2016 and 2021 were retrospectively identified from the Geisinger Health System Research Liver Registry. MASH cases were confirmed using the nonalcoholic fatty liver disease (NAFLD) activity score. Training and validation datasets were used to create an algorithm/predictive model assessing EHR-derived predictors of MASH/MASH with clinically significant fibrosis (fibrosis stage F2-F4). Predictive accuracy was evaluated using the area under the curve.

RESULTS

The analysis included 2698 patients. We created a composite likelihood score using variables significant for MASH and/or MASH with clinically significant fibrosis: liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST]), prior year AST, metabolic disease, pulse (heart rate), and body mass index. The score had higher sensitivity and specificity for predicting MASH than Fibrosis-4 (FIB-4) Index, AST to platelet ratio index (APRI), and NAFLD fibrosis score (NFS); sensitivity and specificity were comparable to FIB-4 and APRI for predicting MASH with clinically significant fibrosis but superior to NFS.

CONCLUSION

The composite likelihood score could potentially be a tool for early MASH screening.

GLP-1RAs regulate lipid metabolism and induce autophagy through AMPK/SIRT1 pathway to improve NAFLD

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a leading cause of cirrhosis and a major risk factor for hepatocellular carcinoma and liver-related death. Diabetes medications have been studied as potential treatments for NAFLD. Glucagon-like peptide-1 agonists (GLP-1RAs) have been rarely reported in the treatment of NAFLD alone as an anti-diabetic drug, and its specific mechanism of action is unknown. We investigated whether the therapeutic effect of liraglutide (LRG, a representative drug of GLP-1RAs) on hepatic steatosis is related to regulating lipid metabolism and enhancing autophagy in the hepatocytes.

METHODS

We examined the effect of LRG on fat accumulation in fatty hepatocytes, and discussed its effects on enzymes related to lipid metabolism and autophagy. Meanwhile, knockdown of SIRT1 in free fatty acids(FFA)-treated cells was used to detected the influence of LRG on lipid metabolism and autophagy by regulating of AMPK/SIRT1 signaling.

RESULTS

Our findings showed that free fatty acids (FFA) induced hepatocyte steatosis, which was significantly reversed by LRG. Meanwhile, LRG significantly regulated the expression of hepatocyte lipogenesis and cytosolic lipolysis-related proteins (FAS, ACC1, ATGL, HSL, LAL). Furthermore, LRG enhanced FFA-induced suppression of autophagy and SIRT1 expression, reducing intracellular lipid accumulation. It is evident that LRG regulates lipid metabolism and induces autophagy in an (AMPK)-dependent manner. Moreover, SIRT1 knockdown inhibited the autophagy-inducing and lipid-lowering effects of LRG.

CONCLUSION

GLP-1RAs may lower hepatic steatosis by regulating lipid metabolism and enhancing autophagy in an AMPK/SIRT1-dependent manner, providing a new target for the treatment of NAFLD.

Network pharmacology-based investigation of the pharmacological mechanisms of diosgenin in nonalcoholic steatohepatitis

The prevalence of nonalcoholic steatohepatitis (NASH) is rising annually, posing health and economic challenges, with limited treatments available. Diosgenin, a natural steroidal compound found in various plants, holds potential as a therapeutic candidate. Recent studies have confirmed diosgenin's anti-inflammatory and metabolism-modulating properties. However, its therapeutic effects on NASH and the underlying mechanisms are still unclear. This study aims to explore diosgenin's protective effects and pharmacological mechanisms against NASH using network pharmacology, molecular docking, and experimental validation. We gathered potential targets of diosgenin and NASH from various databases to generate protein-protein interaction (PPI) networks. GO and KEGG pathway enrichment analyses identified key targets and mechanisms. Molecular docking confirmed the binding capacity between diosgenin and core target proteins. Additionally, a NASH cell model was developed to validate the pharmacological effects of diosgenin. Our investigation identified nine key targets (ALB, AKT1, TP53, VEGFA, MAPK3, EGFR, STAT3, CASP3, IGF1) that interact with diosgenin. Molecular docking indicated potential bindings interactions, while enrichment analyses revealed that diosgenin may enhance fatty acid metabolism via the PI3K-Akt pathway. Cellular experiments confirmed that diosgenin activates this pathway, reduces SCD1 expression, and decreases triglyceride and IL-6 levels. Our study elucidates that diosgenin may ameliorate triglyceride deposition and inflammation through the PI3K-Akt pathway.

Proton density fat fraction for diagnosis of metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND AIMS

Prior work has shown that MRI-derived proton density fat fraction (PDFF) can diagnose metabolic dysfunction-associated steatotic liver disease (MASLD) noninvasively, but there is a paucity of data on the performance of PDFF to classify more advanced forms of the MASLD spectrum. The purpose of this study was to assess the diagnostic performance of PDFF for the diagnoses of MASLD, metabolic dysfunction-associated steatohepatitis (MASH), and fibrotic MASH in adults with obesity undergoing bariatric surgery, using contemporaneous intraoperative liver biopsy as a reference.

APPROACH AND RESULTS

PDFF was evaluated alone and with other potential classifiers (imaging, serum and anthropometric), using Bayesian Information Criterion-based stepwise logistic regression models. Areas under the receiver operating characteristic (ROC) curves (AUC) were computed for all models and single classifiers. Cross-validated sensitivity and specificity were calculated at Youden-based PDFF classification thresholds. Data analysis from 140 patients demonstrated that PDFF was the most accurate single classifier, with high AUC for MASLD (0.95), MASH (0.85), and fibrotic MASH (0.82) (all p <0.001). Multivariable models, including PDFF, outperformed those without PDFF. The Youden-based threshold for PDFF was 4.4% for MASLD (sensitivity: 87%, specificity: 86%), 6.9% for MASH (sensitivity: 77%, specificity: 66%), and 13.5% for fibrotic MASH (sensitivity: 67%, specificity: 85%).

CONCLUSIONS

PDFF was the most accurate single classifier for diagnosing MASLD, MASH, and fibrotic MASH. The most accurate multivariable classification models for MASLD, MASH, and fibrotic MASH included PDFF, demonstrating the central importance of PDFF for noninvasive assessment of the MASLD spectrum.

TARGETING S100A9-TLR2 AXIS CONTROLS MACROPHAGE NLRP3 INFLAMMASOME ACTIVATION IN FATTY LIVER ISCHEMIA REPERFUSION INJURY

ABSTRACT

Liver ischemia reperfusion (IR) injury significantly impacts clinical outcomes by increasing the risk of hepatic dysfunction after liver surgery. Fatty livers are more susceptible to IR stress. Recent studies have demonstrated that S100A9 plays a crucial role in both IR injury and the progression of liver steatosis. Nevertheless, the precise mechanisms underlying these effects remain unclear. In our study, transcriptome analysis of fatty livers subjected to IR insult in mice identified S100A9 as an important mediator. Employing loss-of-function approaches, we investigated the immune regulatory function of S100A9 and its downstream signaling in fatty liver IR injury. As expected, S100A9 emerged as one of the most significantly upregulated genes during the reperfusion stage in fatty livers. Genetic knockdown of S100A9 markedly ameliorated liver pathological damage, evidenced by reduced macrophage/neutrophil infiltration as well as the decreased expression of proinflammatory factors. Transcriptome/functional studies revealed that S100A9 triggered liver inflammatory response via regulating toll-like receptor 2 (TLR2)/activating transcription factor 4 (ATF4) signaling. Additionally, TLR2 expression was notably increased in macrophages from ischemic fatty livers. In vitro , recombinant S100A9-stimulated macrophages exhibited the elevated production of proinflammatory factors and TLR2/ATF4 pathway activation. Intriguingly, S100A9 facilitated ATF4 nuclear translocation and enhanced NEK7/NLRP3 inflammasome activation in macrophages. In conclusion, our study identified S100A9 as a key regulator responsible for macrophage NLRP3 inflammasome activation and subsequent inflammatory injury in fatty liver IR process. Targeting TLR2/ATF4 signaling may offer a novel therapeutic strategy for mitigating S100A9-mediated liver injury.

1-phenyl-3-methyl-5-pyrazolone activates the AMPK pathway to alleviate western-diet induced metabolic dysfunction-associated steatohepatitis in mice

BACKGROUND & AIMS

Approved drugs for the treatment of metabolic dysfunction-associated steatohepatitis (MASH) are limited, although it has become the most common chronic liver disease worldwide. 1-phenyl-3-methyl-5-pyrazolone (PMP) possesses various biological effects such as anti-inflammatory and antioxidant. However, the effects and underlying mechanism of PMP in MASH remain unclear.

METHODS

Steatosis cells were induced by palmitate/oleic acid (PO). Then, the contents of lipids and reactive oxygen species were measured. To further investigate the effects of PMP on MASH models, C57BL/6J mice were fed a western diet (WD) for 24 weeks and PMP was administered daily by intragastric gavage. Serum enzymes and lipids were assayed by a biochemistry analyzer. RNA sequencing, real-time qPCR, and western blotting were used to measure the expression of different genes. Histological analysis of the liver included HE, Oil red O, and Sirius red staining.

RESULTS

PMP alleviated lipid accumulation and oxidative stress induced by PO (P < 0.001). In vivo, WD-induced significant elevation of blood glucose and serum lipids were reduced by PMP (P < 0.05). Furthermore, PMP effectively prevented hepatic steatosis, inflammation, and fibrosis in MASH mice. Western blot results suggested PMP promoted the phosphorylation of LKB1 and AMPKα at T172, which is a marker of activation of the AMPK pathway. RNA sequencing also demonstrated that PMP facilitated the activation of the AMPK pathway. Furthermore, the protective effects of PMP on steatosis cells and MASH mice disappeared after treatment with an AMPK inhibitor.

CONCLUSIONS

PMP protects against metabolic-stress-induced MASH through activating AMPK signaling, indicating that PMP may be a candidate for MASH therapy in the future.

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.

The AMPK-mTOR Pathway Is Inhibited by Chaihu Shugan Powder, Which Relieves Nonalcoholic Steatohepatitis by Suppressing Autophagic Ferroptosis

Nonalcoholic steatohepatitis (NASH) is the advanced stage of nonalcoholic fatty liver disease (NAFLD), which is distinguished by the accumulation of fat in the liver, damage to liver cells, and inflammation. Chaihu Shugan powder (CSP), a renowned traditional Chinese medicine (TCM) blend extensively utilized in China to address liver disease, has demonstrated its efficacy in reducing lipid buildup and effectively combating inflammation. Hence, the primary objective of this research is to examine the impacts and possible mechanisms of CSP on NASH through assessments of liver histopathology, lipidomic analysis, and gene expression. To induce a mouse model of NASH, we employed a diet which deficient in methionine and choline, known as methionine-choline deficient (MCD) diet. Initially, we examined the impact of administering CSP to NASH mice by assessing the levels of serum and liver indicators. We found that CSP was able to reduce lipid buildup and inflammation in mice. In addition, a total of 1009 genes exhibited enrichment in both the autophagy and ferroptosis pathways. The liver protein levels of Adenosine monophosphate-activated protein kinase-mammalian target of rapamycin (AMPK-mTOR)-mediated autophagy and ferroptosis markers, such as p-AMPKα/AMPKα, p-mTOR/mTOR, Beclin-1, microtubule associated protein 1 light chain 3 gamma (LC3), p62 (sequestosome 1 [SQSTM1/p62]), Kelch-like ECH-associated protein 1 (KEAP1), nuclear factor erythroid 2-related factor 2 (Nrf-2), ferritin heavy chain 1 (FTH1), and glutathione peroxidase 4 (GPX4), were restored by CSP. Furthermore, our findings indicated that the suppression of autophagy had a repressive impact on the occurrence of ferroptosis in the mouse model, indicating that autophagy activation likely plays a role in mediating ferroptosis in NASH.

Atractylodes lancea Rhizome Polysaccharide Alleviates MCD Diet-Induced NASH by Inhibiting the p53/mTOR Pathway

Nonalcoholic steatohepatitis (NASH) is a form of chronic liver disease that is characterized by liver inflammation and steatosis, with possible progression to fibrosis. Currently, no drugs have been approved for the treatment of NASH. In this study, we isolated a polysaccharide from Atractylodes lancea rhizome (AP) and established a methionine- and choline-deficient (MCD) diet -induced NASH mouse model to investigate the preventive effect and potential mechanism of AP on NASH. The results showed that AP effectively reduced liver lipid accumulation and inflammation and reduced autophagy and ferroptosis in hepatocytes, thereby preventing the development of NASH. These findings suggest that AP may be a promising natural candidate for the treatment of NASH.

The Global Epidemiology of Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis Among Patients With Type 2 Diabetes

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction associated steatotic liver disease (MASLD), is closely associated with type 2 diabetes (T2D). Our aim was to estimate the most recent global prevalence of NAFLD/MASLD, nonalcoholic steatohepatitis (NASH), now known as metabolic dysfunction associated steatohepatitis (MASH), advanced fibrosis, and mortality among patients with T2D.

METHODS

We systematically searched PubMed and Ovid MEDLINE for terms including NAFLD, NASH, and T2D published in 1990-2023 according to PRISMA. The meta-analysis was conducted using a random-effects model. Assessment of bias risk used the Joanna Briggs Institute appraisal tool.

RESULTS

From 3134 studies included in the initial search, 123 studies (N = 2,224,144 patients with T2D) were eligible. Another 12 studies (N = 2733 T2D patients with liver biopsy) were eligible for histologic assessments. The global pooled prevalence of NAFLD/MASLD among patients with T2D was 65.33% (95% confidence interval, 62.35%-68.18%). This prevalence increased from 55.86% (42.38%-68.53%) in 1990-2004 to 68.81% (63.41%-73.74%) in 2016-2021 (P = .073). The highest NAFLD/MASLD prevalence among T2D patients was observed in Eastern Europe (80.62%, 75.72%-84.73%), followed by the Middle East (71.24%, 62.22%-78.84%), and was lowest in Africa (53.10%, 26.05%-78.44%). Among patients with liver biopsy data, the global pooled prevalence of NASH/MASH, significant fibrosis, and advanced fibrosis was 66.44% (56.61%-75.02%), 40.78% (24.24%-59.70%), and 15.49% (6.99%-30.99%), respectively. The pooled all-cause mortality was 16.79 per 1000 person-years (PY) (10.64-26.40), 4.19 per 1000 PY (1.34-7.05) for cardiac-specific mortality; 6.10 per 1000 PY (0.78-4.88) for extrahepatic cancer-specific mortality; and 2.15 per 1000 PY (0.00-2.21) for liver-specific mortality.

CONCLUSIONS

The prevalence of NAFLD/MASLD among T2D is high and growing. The majority of NAFLD/MASLD patients with T2D have NASH/MASH, and a significant proportion have advanced fibrosis.

TIR8 protects against nonalcoholic steatohepatitis by antagonizing lipotoxicity-induced PPARα downregulation and reducing the sensitivity of hepatocytes to LPS

In up to one-third of nonalcoholic fatty liver disease (NAFLD) patients, simple steatosis progresses to its more severe form, nonalcoholic steatohepatitis (NASH), but the precise mechanisms underlying this transition are not fully understood. Toll/interleukin-1 receptor 8 (TIR8), a conventional innate immune regulator highly expressed in hepatic tissue, has shown potential for ameliorating various inflammation-related disorders. However, its role in NASH pathogenesis, especially its regulatory effects on lipid metabolism and inflammatory responses, is still unclear. Here, using a TIR8 knockout (TIR8KO) mouse model and mass spectrometry analyses, we found that TIR8KO mice displayed aggravated hepatic steatosis and inflammation, whereas TIR8 overexpression attenuated these adverse effects. Ectopic TIR8 expression counteracts free fatty acid (FFA)-induced PPARα inhibition and downstream signaling. A decrease in TIR8 levels in hepatocytes heightened lipopolysaccharide (LPS) sensitivity. Notably, FFA stimulation led to a direct interaction between TIR8 and proteasome subunit alpha type 4 (PSMA4), facilitating TIR8 degradation. These results revealed that TIR8 safeguards PPARα-regulated lipid metabolism and mitigates inflammation induced by external factors during NASH progression. Our study highlights TIR8 as a promising target for NASH therapy, indicating the potential of TIR8 agonists in treatment strategies.

Tanshinone IIA Inhibits the Endoplasmic Reticulum Stress-Induced Unfolded Protein Response by Activating the PPARα/FGF21 Axis to Ameliorate Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH) is a critical stage in the progression of nonalcoholic fatty liver disease (NAFLD). Tanshinone IIA (TIIA) is a tanshinone extracted from Salvia miltiorrhiza; due to its powerful anti-inflammatory and antioxidant biological activities, it is commonly used for treating cardiovascular and hepatic diseases. A NASH model was established by feeding mice a methionine and choline-deficient (MCD) diet. Liver surface microblood flow scanning, biochemical examination, histopathological examination, cytokine analysis through ELISA, lipidomic analysis, transcriptomic analysis, and Western blot analysis were used to evaluate the therapeutic effect and mechanism of TIIA on NASH. The results showed that TIIA effectively reduced lipid accumulation, fibrosis, and inflammation and alleviated endoplasmic reticulum (ER) stress. Lipidomic analysis revealed that TIIA normalized liver phospholipid metabolism in NASH mice. A KEGG analysis of the transcriptome revealed that TIIA exerted its effect by regulating the PPAR signalling pathway, protein processing in the ER, and the NOD-like receptor signalling pathway. These results suggest that TIIA alleviates NASH by activating the PPARα/FGF21 axis to negatively regulate the ER stress-induced unfolded protein response (UPR).

The role of C5aR1-mediated hepatic macrophage efferocytosis in NASH

Non-alcoholic fatty liver disease (NAFLD) has become the first major chronic liver disease in developed countries. 10-20% of NAFLD patients will progress to non-alcoholic steatohepatitis (NASH), and up to 25% of NASH patients may develop cirrhosis within 10 years. Therefore, it is critical to find key targets that may treat this disease. Here, we identified C5aR1 as a highly-expressed gene in NASH mouse model through analyzing Gene Expression Omnibus (GEO) database and confirmed its higher expression in livers of NASH patients than that of NAFL patients. Meanwhile, we verified its positive correlation with patients' serum alanine transaminase (ALT) and aspartate transaminase (AST) levels. In vivo and in vitro experiments revealed that knocking down C5aR1 in liver significantly reduced liver weight ratio and serum ALT and AST levels and attenuated inflammatory cell infiltration and cell apoptosis in the liver of NASH mice as well as enhanced the efferocytotic ability of liver macrophages, suggesting that C5aR1 may play a crucial role in the efferocytosis of liver macrophages. Furthermore, we also found that the expression levels of nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing protein 3 (NLRP3), caspase-1, IL-1β and other inflammation-related factors in the liver were significantly reduced. Our work demonstrates a potential mechanism of how C5aR1 deficiency protects against diet-induced NASH by coordinating the regulation of inflammatory factors and affecting hepatic macrophage efferocytosis.

SerpinB3: A Multifaceted Player in Health and Disease-Review and Future Perspectives

SerpinB3, a member of the serine-protease inhibitor family, has emerged as a crucial player in various physiological and pathological processes. Initially identified as an oncogenic factor in squamous cell carcinomas, SerpinB3's intricate involvement extends from fibrosis progression and cancer to cell protection in acute oxidative stress conditions. This review explores the multifaceted roles of SerpinB3, focusing on its implications in fibrosis, metabolic syndrome, carcinogenesis and immune system impairment. Furthermore, its involvement in tissue protection from oxidative stress and wound healing underscores its potential as diagnostic and therapeutic tool. Recent studies have described the therapeutic potential of targeting SerpinB3 through its upstream regulators, offering novel strategies for cancer treatment development. Overall, this review underscores the importance of further research to fully elucidate the mechanisms of action of SerpinB3 and to exploit its therapeutic potential across various medical conditions.

Hepatocyte-specific loss of DDB1 attenuates hepatic steatosis but aggravates liver inflammation and fibrosis in MASH

BACKGROUND

MASH is a common clinical disease that can lead to advanced liver conditions, but no approved pharmacotherapies are available due to an incomplete understanding of its pathogenesis. Damaged DNA binding protein 1 (DDB1) participates in lipid metabolism. Nevertheless, the function of DDB1 in MASH is unclear.

METHODS

Clinical liver samples were obtained from patients with MASH and control individuals by liver biopsy. Hepatocyte-specific Ddb1-knockout mice and liver Hmgb1 knockdown mice were fed with a methionine-and choline-deficient diet to induce MASH.

RESULTS

We found that the expression of DDB1 in the liver was significantly decreased in MASH models. Hepatocyte-specific ablation of DDB1 markedly alleviated methionine-and choline-deficient diet-induced liver steatosis but unexpectedly exacerbated inflammation and fibrosis. Mechanistically, DDB1 deficiency attenuated hepatic steatosis by downregulating the expression of lipid synthesis and uptake genes. We identified high-mobility group box 1 as a key candidate target for DDB1-mediated liver injury. DDB1 deficiency upregulated the expression and extracellular release of high-mobility group box 1, which further increased macrophage infiltration and activated HSCs, ultimately leading to the exacerbation of liver inflammation and fibrosis.

CONCLUSIONS

These data demonstrate the independent regulation of hepatic steatosis and injury in MASH. These findings have considerable clinical implications for the development of therapeutic strategies for MASH.

Efficacy and safety of aldafermin in non-alcoholic steatohepatitis: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is an advanced subtype of non-alcoholic fatty liver disease (NAFLD). NASH prevalence is increasing exponentially and carries a high risk for disease progression, cirrhosis, and liver-related mortality. Aldafermin, a fibroblast growth factor 19 (FGF19) analog, is one of the evolving therapeutic agents with the potential to regulate multiple pathways involved in the pathogenesis of NASH. We aimed to investigate the efficacy and safety of aldafermin in patients with NASH.

METHODS

PubMed, Scopus, Cochrane Library, and Web of Science were searched till November 2023 to identify eligible randomized controlled trials (RCTs). Continuous data were pooled as mean difference (MD), while dichotomous data were pooled as risk ratios (RR) with a 95 % confidence interval. A subgroup meta-analysis was conducted to evaluate the efficacy of the two doses (1 mg and 3 mg) of aldafermin.

RESULTS

Four RCTs with a total of 491 patients were included. Aldafermin showed a dose-dependent improvement in the ≥30 % reduction in the liver fat content (RR: 2.16, 95 % CI [1.41 to 3.32]) and (RR: 5.00, 95 % CI [1.34 to 18.64]), alanine aminotransferase levels (MD: -19.79, 95 % CI [-30.28 to -9.3]) and (MD: -21.91, 95 % CI [-29.62 to -14.21]), aspartate aminotransferase levels (MD: -11.79, 95 % CI [-18.06 to -5.51]) and (MD: -13.9, 95 % CI [-18.59 to -9.21]), and enhanced liver fibrosis score (ELF) (MD: -0.13, 95 % CI [-0.29 to 0.02]) and (MD: -0.33, 95 % CI [-0.50 to -0.17]), in the 1 mg and 3 mg subgroups respectively. No significant differences were detected in the aldafermin group regarding histologic endpoints, lipid profile, metabolic parameters, and overall adverse effects, except for the increased occurrence of diarrhea in the aldafermin 3 mg subgroup.

CONCLUSION

Aldafermin is a promising well-tolerated therapeutic agent for NASH with evidence supporting its ability to reduce liver fat content, fibrosis serum biomarkers, and liver enzymes. However, its effectiveness in improving histologic fibrosis, while showing numerical trends, still lacks statistical significance. Larger and longer NASH trials are warranted to enhance the robustness of the evidence.

Influence of nonalcoholic fatty liver disease severity on carotid adventitial vasa vasorum

Introduction

Nonalcoholic fatty liver disease (NAFLD) affects a quarter of the world's population and encompasses a spectrum of liver conditions, from non-alcoholic steatohepatitis (NASH) to inflammation and fibrosis. In addition, NAFLD also links to extrahepatic conditions like diabetes or obesity. However, it remains unclear if NAFLD independently correlates with the onset and progression of atherosclerosis.

Material and methods

This cross-sectional study aimed to explore the relationship between NAFLD severity, assessed via liver biopsy, and early atherosclerosis using adventitial vasa vasorum (VV) density. It included 44 patients with obesity (33 with steatosis, 11 with NASH) undergoing bariatric surgery.

Results

Results revealed no significant differences in adventitial VV density between steatosis and NASH groups, neither in the mean values [0.759 ± 0.104 vs. 0.780 ± 0.043, P=0.702] nor left-right sides. Similarly, carotid intima-media thickness (cIMT) did not vary between these groups. Additionally, no linear correlation existed between VV density and cIMT. Only gender showed an association with VV density.

Conclusion

These findings suggest that NASH severity doesn't independently drive early atherosclerosis or affects cIMT. Gender might play a role in early atherosclerotic disease in NAFLD, impacting VV density and cIMT. This highlights the need to consider other risk factors when evaluating cardiovascular risk in NAFLD patients.

The protease activated receptor 2 - CCAAT/enhancer-binding protein beta - SerpinB3 axis inhibition as a novel strategy for the treatment of non-alcoholic steatohepatitis

OBJECTIVE

The serine protease inhibitor SerpinB3 has been described as critical mediator of liver fibrosis and it has been recently proposed as an additional hepatokine involved in NASH development and insulin resistance. Protease Activated Receptor 2 has been identified as a novel regulator of hepatic metabolism. A targeted therapeutic strategy for NASH has been investigated, using 1-Piperidine Propionic Acid (1-PPA), since this compound has been recently proposed as both Protease Activated Receptor 2 and SerpinB3 inhibitor.

METHODS

The effect of SerpinB3 on inflammation and fibrosis genes was assessed in human macrophage and stellate cell lines. Transgenic mice, either overexpressing SerpinB3 or carrying Serpinb3 deletion and their relative wild type strains, were used in experimental NASH models. Subgroups of SerpinB3 transgenic mice and their controls were also injected with 1-PPA to assess the efficacy of this compound in NASH inhibition.

RESULTS

1-PPA did not present significant cell and organ toxicity and was able to inhibit SerpinB3 and PAR2 in a dose-dependent manner. This effect was associated to a parallel reduction of the synthesis of the molecules induced by endogenous SerpinB3 or by its paracrine effects both in vitro and in vivo, leading to inhibition of lipid accumulation, inflammation and fibrosis in experimental NASH. At mechanistic level, the antiprotease activity of SerpinB3 was found essential for PAR2 activation, determining upregulation of the CCAAT Enhancer Binding Protein beta (C/EBP-β), another pivotal regulator of metabolism, inflammation and fibrosis, which in turn determined SerpinB3 synthesis.

CONCLUSIONS

1-PPA treatment was able to inhibit the PAR2 - C/EBP-β - SerpinB3 axis and to protect from NASH development and progression, supporting the potential use of a similar approach for a targeted therapy of NASH.

Making Sense of the Nonalcoholic Fatty Liver Disease Clinical Practice Guidelines: What Clinicians Need to Know

Standards of care summarized in clinical practice guidelines for nonalcoholic fatty liver disease (NAFLD) offer clinicians a streamlined diagnostic and management approach based on the best available evidence. These recommendations have changed a great deal in recent years; today, there is a clear focus on screening for the early identification and risk stratification of patients at high risk of steatohepatitis and clinically significant fibrosis to promote timely referrals to specialty care when needed. This article reviews and provides the rationale for current guidelines for NAFLD screening, diagnosis, treatment, and monitoring and addresses barriers to providing evidence-based NAFLD care and how to overcome them. The current paradigm of care calls for primary care clinicians and specialists to work together, within a multidisciplinary care team familiar with obesity and diabetes care, to provide comprehensive management of these complex patients.

Limitations of Noninvasive Tests-Based Population-Level Risk Stratification Strategy for Nonalcoholic Fatty Liver Disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are highly prevalent but underdiagnosed.

AIMS

We used an electronic health record data network to test a population-level risk stratification strategy using noninvasive tests (NITs) of liver fibrosis.

METHODS

Data were obtained from PCORnet® sites in the East, Midwest, Southwest, and Southeast United States from patients aged [Formula: see text] 18 with or without ICD-10-CM diagnosis codes for NAFLD, NASH, and NASH-cirrhosis between 9/1/2017 and 8/31/2020. Average and standard deviations (SD) for Fibrosis-4 index (FIB-4), NAFLD fibrosis score (NFS), and Hepatic Steatosis Index (HSI) were estimated by site for each patient cohort. Sample-wide estimates were calculated as weighted averages across study sites.

RESULTS

Of 11,875,959 patients, 0.8% and 0.1% were coded with NAFLD and NASH, respectively. NAFLD diagnosis rates in White, Black, and Hispanic patients were 0.93%, 0.50%, and 1.25%, respectively, and for NASH 0.19%, 0.04%, and 0.16%, respectively. Among undiagnosed patients, insufficient EHR data for estimating NITs ranged from 68% (FIB-4) to 76% (NFS). Predicted prevalence of NAFLD by HSI was 60%, with estimated prevalence of advanced fibrosis of 13% by NFS and 7% by FIB-4. Approximately, 15% and 23% of patients were classified in the intermediate range by FIB-4 and NFS, respectively. Among NAFLD-cirrhosis patients, a third had FIB-4 scores in the low or intermediate range.

CONCLUSIONS

We identified several potential barriers to a population-level NIT-based screening strategy. HSI-based NAFLD screening appears unrealistic. Further research is needed to define merits of NFS- versus FIB-4-based strategies, which may identify different high-risk groups.

A Machine Learning Model to Predict Risk for Hepatocellular Carcinoma in Patients With Metabolic Dysfunction-Associated Steatotic Liver Disease

Background and Aims

Hepatocellular carcinoma (HCC) incidence is increasing and correlated with metabolic dysfunction-associated steatotic liver disease (MASLD; formerly nonalcoholic fatty liver disease), even in patients without advanced liver fibrosis who are more likely to be diagnosed with advanced disease stages and shorter survival time, and less likely to receive a liver transplant. Machine learning (ML) tools can characterize large datasets and help develop predictive models that can calculate individual HCC risk and guide selective screening and risk mitigation strategies.

Methods

Tableau and KNIME Analytics were used for descriptive analytics and ML tasks. ML models were developed using standard laboratory and clinical parameters. Sci-kit learn algorithms were used for model development. Data from University of California (UC), Davis, were used to develop and train a pilot predictive model, which was subsequently validated in an independent dataset from UC San Francisco. MASLD and HCC patients were identified by International Classification of Diseases-9/10 codes.

Results

Of the patients diagnosed with MASLD (n = 1561 training; n = 686 validation), HCC developed in 14% (n = 227) of the UC Davis training cohort and 25% (n = 176) of the UC San Francisco validation cohort. Liver fibrosis determined by the noninvasive Fibrosis-4 score was the strongest single predictor for HCC in the model. Using the validation cohort, the model predicted HCC development at 92.06% accuracy with an area under the curve of 0.97, F1-score of 0.84, 98.34% specificity, and 74.41% sensitivity.

Conclusion

ML models can aid physicians in providing early HCC risk assessment in patients with MASLD. Further validation will translate to cost-effective, personalized care of at-risk patients.

Discovery of 4-aminophenylacetamide derivatives as intestine-specific farnesoid X receptor antagonists for the potential treatment of nonalcoholic steatohepatitis

Farnesoid X receptor (FXR) plays a key role in bile acid homeostasis, inflammation, fibrosis, lipid and glucose metabolism and is emerging as a promising therapeutic target for nonalcoholic steatohepatitis (NASH). Emerging evidence suggested that intestine-specific FXR antagonists exhibited remarkable metabolic improvements and slowed NASH progression. In this study, we discovered several potent FXR antagonists using a multistage ligand- and structure-based virtual screening approach. Notably, compound V023-9340, which possesses a 4-aminophenylacetamide scaffold, emerged as the most potent FXR antagonist with an IC50 value of 4.27 μM. In vivo, V023-9340 demonstrated selective accumulation in the intestine, substantially ameliorating high-fat diet (HFD)-induced NASH in mice by mitigating hepatic steatosis and inflammation. Mechanistic studies revealed that V023-9340 strongly inhibited intestinal FXR while concurrently feedback-activated hepatic FXR. Further structure-activity relationship optimization employing V023-9340 has resulted in the synthesis of a more efficacious compound V02-8 with an IC50 value of 0.89 μM, which exhibited a 4.8-fold increase in FXR antagonistic activity compared to V023-9340. In summary, 4-aminophenylacetamide derivative V023-9340 represented a novel intestine-specific FXR antagonist and showed improved effects against HFD-induced NASH in mice, which may serve as a promising lead in discovering potential therapeutic drugs for NASH treatment.

Cell-type specific role of autophagy in the liver and its implications in non-alcoholic fatty liver disease

Autophagy, a cellular degradative process, has emerged as a key regulator of cellular energy production and stress mitigation. Dysregulated autophagy is a common phenomenon observed in several human diseases, and its restoration offers curative advantage. Non-alcoholic fatty liver disease (NAFLD), more recently renamed metabolic dysfunction-associated steatotic liver disease, is a major metabolic liver disease affecting almost 30% of the world population. Unfortunately, NAFLD has no pharmacological therapies available to date. Autophagy regulates several hepatic processes including lipid metabolism, inflammation, cellular integrity and cellular plasticity in both parenchymal (hepatocytes) and non-parenchymal cells (Kupffer cells, hepatic stellate cells and sinusoidal endothelial cells) with a profound impact on NAFLD progression. Understanding cell type-specific autophagy in the liver is essential in order to develop targeted treatments for liver diseases such as NAFLD. Modulating autophagy in specific cell types can have varying effects on liver function and pathology, making it a promising area of research for liver-related disorders. This review aims to summarize our present understanding of cell-type specific effects of autophagy and their implications in developing autophagy centric therapies for NAFLD.

Isotope Labeling and Biochemical Assessment of Liver-Triacylglycerol in Patients with Different Levels of Histologically-Graded Liver Disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) prevalence is rapidly growing, and fatty liver has been found in a quarter of the US population. Increased liver lipids, particularly those derived from the pathway of de novo lipogenesis (DNL), have been identified as a hallmark feature in individuals with high liver fat. This has led to much activity in basic science and drug development in this area. No studies to date have investigated the contribution of DNL across a spectrum of disease, although it is clear that inhibition of DNL has been shown to reduce liver fat.

OBJECTIVES

The purpose of this study was to determine whether liver lipid synthesis increases across the continuum of liver injury.

METHODS

Individuals (n = 49) consumed deuterated water for 10 d before their scheduled bariatric surgeries to label DNL; blood and liver tissue samples were obtained on the day of the surgery. Liver lipid concentrations were quantitated, and levels of protein and gene expression assessed.

RESULTS

Increased liver DNL, measured isotopically, was significantly associated with liver fatty acid synthase protein content (R = 0.470, P = 0.003), total steatosis assessed by histology (R = 0.526, P = 0.0008), and the fraction of DNL fatty acids in plasma very low-density lipoprotein-triacylglycerol (R = 0.747, P < 0.001). Regression analysis revealed a parabolic relationship between fractional liver DNL (percent) and NAFLD activity score (R = 0.538, P = 0.0004).

CONCLUSION

These data demonstrate that higher DNL is associated with early to mid stages of liver disease, and this pathway may be an effective target for the treatment of NAFLD and nonalcoholic steatohepatitis. This study was registered at clinicaltrials.gov as NCT03683589.

Nonalcoholic steatohepatitis diagnosis and treatment from the perspective of patients and primary care physicians: a cross-sectional survey

BACKGROUND

The global prevalence of nonalcoholic steatohepatitis (NASH) is rising. Despite this, NASH is underdiagnosed and does not yet have approved pharmacological treatments. We sought to understand the path to diagnosis, patient interactions with healthcare professionals, treatment regimens, and disease management for patients with NASH.

METHODS

Cross-sectional online surveys of patients with a self-reported diagnosis of NASH and healthcare professionals treating patients with NASH were conducted from 10^th November 2020, to 1st January 2021. This manuscript focuses on responses from 152 patients with NASH and 101 primary care physicians (PCPs).

RESULTS

Patients (n = 152, mean age = 40, SD = 11) and healthcare professionals (n = 226) were located throughout the US. In the most common patient journey, 72% of patients had initial discussions about symptoms with a PCP but only 30% report receiving their NASH diagnosis from a PCP. Almost half of PCPs (47%) were not aware of any clinical practice guidelines for diagnosis and management of NASH. For ongoing management of NASH, PCPs most frequently prescribed lifestyle changes such as exercise (89%), lifestyle changes focused on diet (79%), and/or metformin (57%). Other healthcare professionals rarely referred patients to PCPs for treatment, but when they did, the primary reasons were patients struggling with lifestyle modifications (58%), needing to lose weight (46%), and needing treatment of comorbidities (42%).

CONCLUSIONS

PCPs may benefit from greater awareness of NASH and guidelines for its diagnosis and treatment. Given the absence of pharmacological treatments approved for NASH, PCPs can offer support in obesity management, comorbidity management, and risk stratification for liver disease progression.

Prescribing of evidence-based diabetes pharmacotherapy in patients with metabolic dysfunction-associated steatohepatitis

INTRODUCTION

Metabolic dysfunction-associated steatohepatitis (MASH) is highly prevalent in type 2 diabetes (T2D). Pioglitazone and glucagon-like peptide-1 receptor agonists (GLP-1RA) are medications used in T2D that can resolve MASH and should be considered in all patients with T2D and MASH. We assessed prescription rates of evidence-based T2D pharmacotherapy (EBP) in MASH, and ascertained racial/ethnic disparities in prescribing.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional study on patients in Duke University Health System with diagnosis codes for T2D and MASH between January 2019 and January 2021. Only patients with ≥1 primary care or endocrinology encounter were included. The primary outcome was EBP, defined as ≥1 prescription for pioglitazone and/or a GLP-1RA during the study period. A multivariable logistic regression model was used to examine the primary outcome.

RESULTS

A total of 847 patients with T2D and MASH were identified; mean age was 59.7 (SD 12) years, 61.9% (n=524) were female, and 11.9% (n=101) and 4.6% (n=39) were of Black race and Latino/a/x ethnicity, respectively. EBP was prescribed in 34.8% (n=295). No significant differences were noted in the rates of EBP use across racial/ethnic groups (Latino/a/x vs White patients: adjusted OR (aOR) 1.82, 95% CI 0.78 to 4.28; Black vs White patients: aOR 0.76, 95% CI 0.44 to 1.33, p=0.20).

CONCLUSIONS

EBP prescriptions, especially pioglitazone, are low in patients with T2D and MASH, regardless of race/ethnicity. These data underscore the need for interventions to close the gap between current and evidence-based care.

Sex-based differences in natural killer T cell-mediated protection against diet-induced steatohepatitis in Balb/c mice

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is prevalent in Western countries, evolving into metabolic dysfunction-associated steatohepatitis (MASH) with a sexual dimorphism. Fertile women exhibit lower MASLD risk than men, which diminishes post-menopause. While NKT-cell involvement in steatohepatitis is debated, discrepancies may stem from varied mouse strains used, predominantly C57BL6/J with Th1-dominant responses. Exploration of steatohepatitis, encompassing both genders, using Balb/c background, with Th2-dominant immune response, and CD1d-deficient mice in the Balb/c background (lacking Type I and Type II NKT cells) can clarify gender disparities and NKT-cell influence on MASH progression.

METHODS

A high fat and choline-deficient (HFCD) diet was used in male and female mice, Balb/c mice or CD1d-/- mice in the Balb/c background that exhibit a Th2-dominant immune response. Liver fibrosis and inflammatory gene expression were measured by qPCR, and histology assessment. NKT cells, T cells, macrophages and neutrophils were assessed by flow cytometry.

RESULTS

Female mice displayed milder steatohepatitis after 6 weeks of HFCD, showing reduced liver damage, inflammation, and fibrosis compared to males. Male Balb/c mice exhibited NKT-cell protection against steatohepatitis whereas CD1d-/- males on HFCD presented decreased hepatoprotection, increased liver fibrosis, inflammation, neutrophilic infiltration, and inflammatory macrophages. In contrast, the NKT-cell role was negligible in early steatohepatitis development in both female mice, as fibrosis and inflammation were similar despite augmented liver damage in CD1d-/- females. Relevant, hepatic type I NKT levels in female Balb/c mice were significantly lower than in male.

CONCLUSIONS

NKT cells exert a protective role against experimental steatohepatitis as HFCD-treated CD1d-/- males had more severe fibrosis and inflammation than male Balb/c mice. In females, the HFCD-induced hepatocellular damage and the immune response are less affected by NKT cells on early steatohepatitis progression, underscoring sex-specific NKT-cell influence in MASH development.

Liver biopsy-based validation, confirmation and comparison of the diagnostic performance of established and novel non-invasive steatotic liver disease indexes: Results from a large multi-center study

BACKGROUND

Non-invasive tools (NIT) for metabolic-dysfunction associated liver disease (MASLD) screening or diagnosis need to be thoroughly validated using liver biopsies.

PURPOSE

To externally validate NITs designed to differentiate the presence or absence of liver steatosis as well as more advanced disease stages, to confirm fully validated indexes (n = 7 NITs), to fully validate partially validated indexes (n = 5 NITs), and to validate for the first time one new index (n = 1 NIT).

METHODS

This is a multi-center study from two Gastroenterology-Hepatology Departments (Greece and Australia) and one Bariatric-Metabolic Surgery Department (Italy). Overall, n = 455 serum samples of patients with biopsy-proven MASLD (n = 374, including 237 patients with metabolic-dysfunction associated steatohepatitis (MASH)) and Controls (n = 81) were recruited. A complete validation analysis was performed to differentiate the presence of MASLD vs. Controls, MASH vs. metabolic-dysfunction associated steatotic liver (MASL), histological features of MASH, and fibrosis stages.

RESULTS

The index of NASH (ION) demonstrated the highest differentiation ability for the presence of MASLD vs. Controls, with the area under the curve (AUC) being 0.894. For specific histological characterization of MASH, no NIT demonstrated adequate performance, while in the case of specific features of MASH, such as hepatocellular ballooning and lobular inflammation, ION demonstrated the best performance with AUC being close to or above 0.850. For fibrosis (F) classification, the highest AUC was reached by the aspartate aminotransferase to platelet ratio index (APRI) being ~0.850 yet only with the potential to differentiate the severe fibrosis stages (F3, F4) vs. mild or moderate fibrosis (F0-2) with an AUC > 0.900 in patients without T2DM. When we excluded patients with morbid obesity, the differentiation ability of APRI was improved, reaching AUC = 0.802 for differentiating the presence of fibrosis F2-4 vs. F0-1. The recommended by current guidelines index FIB-4 seemed to differentiate adequately between severe (i.e., F3-4) and mild or moderate fibrosis (F0-2) with an AUC = 0.820, yet this was not the case when FIB-4 was used to classify patients with fibrosis F2-4 vs. F0-1. Trying to improve the predictive value of all NITs, using Youden's methodology, to optimize the suggested cut-off points did not materially improve the results.

CONCLUSIONS

The validation of currently available NITs using biopsy-proven samples provides new evidence for their ability to differentiate between specific disease stages, histological features, and, most importantly, fibrosis grading. The overall performance of the examined NITs needs to be further improved for applications in the clinic.

Prevalence and Determinants of Undiagnosed Liver Steatosis and Fibrosis in a Nationally Representative Sample of US Adults

Background Chronic liver diseases account for approximately 1.9 million deaths globally every year and negatively affect health-related quality of life. Early detection of liver disease may enable timely treatment, potentially improving patient outcomes. This study aimed to determine the prevalence and determinants of liver steatosis and fibrosis in US adults with no previously diagnosed liver condition. Methods We conducted an observational, nationally representative, cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) conducted from January 2017 to March 2020. Study participants were 7,391 adults aged 21 and older with no history of diagnosed liver disorders who underwent vibration-controlled transient elastography (VCTE) to determine liver steatosis and fibrosis. Controlled attenuation parameter (CAP) values between 248 and 267 dB/m were classified as mild steatosis, and those over 267 dB/m as advanced steatosis. Liver stiffness measurement (LSM) values between 7.65 and 13 kPa were classified as moderate/severe fibrosis, and those over 13 kPa as cirrhosis. Covariates included age, sex, race, body mass index (BMI), diabetes mellitus, kidney disease, smoking history, alcohol intake, alanine aminotransferase (ALT), aspartate aminotransferase (AST), physical activity, sedentary time, and sleep time. The associations of subject characteristics with liver CAP and LSM were evaluated using survey multivariable linear regression. Shapley Additive Explanations values determined the relative importance of each attribute in the model. The discriminative performance of classification models was assessed using the area under the receiver operating characteristic (AUROC) curve. Results The population prevalence of liver steatosis was 57.2% (10.2% mild; 47.0% advanced). The relative importance of covariates in predicting liver CAP was 63.1% for BMI, 10.7% for ALT, and less than 10% for the other covariates. The prevalence of significant fibrosis was 11.4% (8.3% moderate/severe fibrosis; 3.1% cirrhosis). The relative importance of covariates in predicting LSM was 67.3% for BMI and less than 10% for the other covariates. BMI alone demonstrated acceptable discriminative performance in classifying varying severities of steatosis and fibrosis (AUROC range 72%-78%) at cutoffs between 28 and 33 kg/m2. Conclusions Undiagnosed chronic liver disease based on VCTE findings is highly prevalent among US adults, particularly in obese individuals. Efforts to increase awareness about liver disease and to reconsider existing BMI thresholds for liver disease screening may be warranted.

Liver fat as risk factor of hepatic and cardiometabolic diseases

Non-alcoholic fatty liver disease (NAFLD) is a disorder characterized by excessive accumulation of fat in the liver that can progress to liver inflammation (non-alcoholic steatohepatitis [NASH]), liver fibrosis, and cirrhosis. Although most efforts for drug development are focusing on the treatment of the latest stages of NAFLD, where significant fibrosis and NASH are present, findings from studies suggest that the amount of liver fat may be an important independent risk factor and/or predictor of development and progression of NAFLD and metabolic diseases. In this review, we first describe the current tools available for quantification of liver fat in humans and then present the clinical and pathophysiological evidence that link liver fat with NAFLD progression as well as with cardiometabolic diseases. Finally, we discuss current pharmacological and non-pharmacological approaches to reduce liver fat and present open questions that have to be addressed in future studies.

Development and validation for bioanalysis of VK2809, its active metabolite VK2809A and glutathione-conjugated metabolite MB06588 in rat liver using LC-MS/MS

VK2809 is a promising drug candidate in Phase II clinical trials for the treatment of non-alcoholic steatohepatitis (NASH). It is a prodrug with a HepDirect strategy, which can achieve selective hepatic metabolic activation, generating an active metabolite VK2809A as a potent and selective agonist for thyroid hormone receptor beta (TRβ), a concomitant reactive metabolite VK2809B, and a glutathione (GSH) conjugate MB06588. Currently, there is no convenient and sensitive bioanalytical method for the simultaneous determination of the above three metabolites. Herein, we established an LC-MS/MS method to separate VK2809 and its metabolites on the XSelect HSS T3 column and quantified them in negative electrospray ionization mode. Subsequently, several factors were investigated such as the use of 60% acetonitrile for homogenization to stabilize the analytes, the addition of 20 mM glutathione for the derivation of VK2809B, and the protein precipitation with methanol containing Sobetirome as the internal standard (IS). The method exhibited good linearity for all compounds (19.4-388.4 nM for VK2809; 27.4-2744.4 nM for VK2809A and 10.6-211.0 nM for MB06588) with great correlation coefficients (r > 0.996). The method validation also demonstrated acceptable precision (RSD < 13.0% for VK2809, RSD < 7.9% for VK2809A, RSD < 14.4% for MB06588) and accuracy (92.7%-103% for VK2809, 91.2%-107.3% for VK2809A, 96%-106.7% for MB06588). The matrix effect, recovery, and stability were also suitable to determine all the analytes. This method is suitable for the bioanalysis of VK2809 and its metabolites and has been successfully applied to the study of intrahepatic exposure in rats. It is expected to be further practiced in drug design, optimization, and metabolism study in the following research.

Prevention of Hepatocellular Carcinoma (HCC). White Paper of the Texas Collaborative Center for Hepatocellular Cancer (TeCH) Multi-stakeholder Conference

BACKGROUND & AIMS

Texas has the highest age-adjusted incidence rate of hepatocellular carcinoma (HCC) in the United States. The Cancer Prevention and Research Institute of Texas has funded the Texas Collaborative Center for Hepatocellular Cancer (TeCH) to facilitate HCC research, education, and advocacy activities with the overall goal of reducing HCC mortality in Texas through coordination, collaboration, and advocacy.

METHODS

On September 17, 2022, TeCH co-sponsored a multi-stakeholder conference on HCC with the Baker Institute Center for Health and Biosciences. This conference was attended by HCC researchers, policy makers, payers, members from pharmaceutical industry and patient advocacy groups in and outside of Texas. This report summarizes the results of the conference.

RESULTS

The goal of this meeting was to identify different strategies for preventing HCC and evaluate their readiness for implementation.

CONCLUSIONS

We call for a statewide (1) viral hepatitis elimination program; (2) program to increase nonalcoholic steatohepatitis and obesity awareness; (3) research program to develop health care models that integrate alcohol associated liver disease treatment and treatment for alcohol use disorder; and (4) demonstration projects to evaluate the effectiveness of identifying and linking patient with advanced fibrosis and cirrhosis to clinical care.

Mitochondrial general control of amino acid synthesis 5 like 1 promotes nonalcoholic steatohepatitis development through ferroptosis-induced formation of neutrophil extracellular traps

BACKGROUND

Mitochondria play central roles in metabolic diseases including nonalcoholic steatohepatitis (NASH). However, how mitochondria regulate NASH progression remains largely unknown. Our previous findings demonstrate that mitochondrial general control of amino acid synthesis 5 like 1 (GCN5L1) is associated with mitochondrial metabolism. Nevertheless, the roles of GCN5L1 in NASH are unclear.

AIMS AND METHODS

The GCN5L1 expression was detected in the fatty livers of NASH patients and animals. Hepatocyte-specific GCN5L1 deficiency or overexpression mice were used to induce NASH models by feeding with a high-fat/high-cholesterol or methionine-choline deficient diet. The molecular mechanisms underlying GCN5L1-regulated NASH were further explored and verified in mice.

RESULTS AND CONCLUSIONS

GCN5L1 expression was increased in NASH patients. Upregulated GCN5L1 level was also illustrated in NASH mice. Mice with hepatocyte-specific GCN5L1 conditional knockout improved the inflammatory response compared to GCN5L1flox/flox mice. However, overexpression of mitochondrial GCN5L1 augmented the inflammatory response. Mechanically, GCN5L1 acetylated CypD and enhanced its binding with ATP5B, which induced the opening of mitochondrial permeability transition pores and the release of mitochondrial ROS into the cytoplasm. The increased ROS promoted ferroptosis of hepatocytes and induced accumulation of high mobility group box 1 in the microenvironment, which recruited neutrophils and induced the generation of neutrophil extracellular traps (NETs). NETs block impaired GCN5L1-induced NASH progression. Furthermore, the upregulation of GCN5L1 in NASH was contributed by lipid overload-induced endoplasmic reticulum stress. Together, mitochondrial GCN5L1 has a vital function in promoting NASH progression by regulating oxidative metabolism and the hepatic inflammatory microenvironment. Thus, GCN5L1 might be a potential intervention target in NASH treatment.

Opportunities and considerations for studying liver disease with microphysiological systems on a chip

Advances in microsystem engineering have enabled the development of highly controlled models of the liver that better recapitulate the unique in vivo biological conditions. In just a few short years, substantial progress has been made in creating complex mono- and multi-cellular models that mimic key metabolic, structural, and oxygen gradients crucial for liver function. Here we review: 1) the state-of-the-art in liver-centric microphysiological systems and 2) the array of liver diseases and pressing biological and therapeutic challenges which could be investigated with these systems. The engineering community has unique opportunities to innovate with new liver-on-a-chip devices and partner with biomedical researchers to usher in a new era of understanding of the molecular and cellular contributors to liver diseases and identify and test rational therapeutic modalities.

Comparison of Pathway Referrals for Liver Fibrosis Risk Stratification Performed in Diabetology and Nutrition Clinics

Purpose

A systematic screening for the presence of nonalcoholic fatty liver disease (NAFLD)-related advanced fibrosis is currently recommended in patients with type 2 diabetes mellitus (T2DM) and obesity. However, real-world data of such liver fibrosis risk stratification pathway from diabetology and nutrition clinics towards hepatology clinics are scarce. Therefore, we compared data from two pathways with or without transient elastography (TE) performed in diabetology and nutrition clinics.

Patients and Methods

This is a retrospective study comparing the proportion of patients with intermediate/high risk of advanced fibrosis (AF) as defined by a liver stiffness measurement (LSM) ≥8kPa, among patients referred in hepatology from two diabetology-nutrition departments at Lyon University Hospital, France between November 1st 2018 to December 31st 2019.

Results

Among the two diabetology and nutrition departments using TE or not, 27.5% (62/225) versus 44.2% (126/285) were referred to hepatology, respectively. The pathway using TE in diabetology and nutrition referred to hepatology a higher proportion of patients with intermediate/high risk of AF compared to the pathway without TE: 77.4% versus 30.9%, p<0.001. In the pathway with TE, the odds of patients with intermediate/high risk of AF referred to hepatology was significantly higher: OR: 7.7, 95% CI: 3.6-16.7, p<0.001 after adjustment for age, sex and presence of obesity and T2D compared to the pathway without TE in diabetology and nutrition clinics. However, among the patients not referred, 29.4% had an intermediate/high risk of AF.

Conclusion

A pathway-referral using TE performed in diabetology and nutrition clinics, significantly improves the liver fibrosis risk stratification and avoids over-referral. However, collaboration between diabetologist, nutritionists and hepatologists is needed to avoid under-referral.

Clinical characteristics and management of patients with nonalcoholic steatohepatitis in a real-world setting: analysis of the Ipsos NASH therapy monitor database

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is the more severe, inflammatory type of nonalcoholic fatty liver disease (NAFLD). NASH, a leading indication for liver transplantation, is growing in prevalence. The extent of liver fibrosis, ranging from fibrosis stage (FS) of none (F0) to cirrhosis (F4), is a strong predictor of health outcomes. There is little information on patient demographics and clinical characteristics by fibrosis stage and NASH treatment outside of academic medical centers.

METHODS

We conducted a cross-sectional observational study using Ipsos' syndicated NASH Therapy Monitor database, consisting of medical chart audits provided by sampled NASH-treating physicians in the United States in 2016 (n = 174) and 2017 (n = 164). Data was collected online.

RESULTS

Of 2,366 patients reported on by participating physicians and included in the analysis, 68% had FS F0-F2, 21% had bridging fibrosis (F3), and 9% had cirrhosis (F4). Common comorbidities were type 2 diabetes (56%), hyperlipidemia (44%), hypertension (46%), and obesity (42%). Patients with more advanced fibrosis scores (F3-F4) had higher comorbidity rates than patients with F0-F2. Commonly used diagnostic tests included ultrasound (80%), liver biopsy (78%), AST/ALT ratio (43%), NAFLD fibrosis score (25%), transient elastography (23%), NAFLD liver fat score (22%), and Fatty Liver Index (19%). Most commonly prescribed medications were vitamin E (53%), statins (51%), metformin (47%), angiotensin converting enzyme inhibitors (28%), and beta blockers (22%). Medications were commonly prescribed for reasons other than their known effects.

CONCLUSION

Physicians in this study, drawn from a spectrum of practice settings, relied on ultrasound and liver biopsy for diagnosis and vitamin E, statins, and metformin for pharmacological treatment of NASH. These findings imply poor adherence to guidelines in the diagnosis and management of NAFLD and NASH. Nonalcoholic steatohepatitis (NASH) is a liver disease caused by excess fat in the liver which can lead to liver inflammation and scarring (fibrosis), ranging from stage F0 (no scarring) to F4 (advanced scarring). The stage of liver scarring can predict the likelihood of future health problems, including liver failure and liver cancer. However, we do not fully understand how patient characteristics may vary at different stages of liver scarring. We looked at medical information from physicians treating patients diagnosed with NASH to understand how patient characteristics might differ based on the severity of their liver scarring. The majority (68%) of patients were stage F0-F2, with 30% having advanced scarring (F3-F4). In addition to NASH, many patients also had type 2 diabetes, high cholesterol, high blood pressure, and obesity. Patients with more advanced scarring (F3-F4) were more likely to have these diseases than patients with less severe disease (F0-F2). Diagnosis of NASH by participating physicians was based on tests including imaging (ultrasound, CT scan, MRI), liver biopsy, blood tests, and whether patients had other conditions that would put them at risk for NASH. The medications that the doctors prescribed most often to their patients included vitamin E and drugs to treat high cholesterol, high blood pressure, or diabetes. Medications were frequently prescribed for reasons other than their known effects. By understanding how patient characteristics vary by stages of liver scarring and how NASH is currently managed may help guide the evaluation and treatment of NASH when NASH-specific therapies become available.

How to Identify Advanced Nonalcoholic Fatty Liver Disease in the Primary Care Setting

Nonalcoholic fatty liver disease (NAFLD) affects 30 to 40% of the population globally and is increasingly considered the most common liver disease. Patients with type 2 diabetes, obesity, and cardiovascular diseases are at especially increased risk for NAFLD. Although most patients with NAFLD do not have progressive liver disease, some patients progress to cirrhosis, liver cancer, and liver mortality. Given the sheer number of patients with NAFLD, the burden of disease is enormous. Despite this large and increasing burden, identification of NAFLD patients at risk for progressive liver disease in the primary care and diabetology practice settings remains highly suboptimal. In this review, our aim is to summarize a stepwise approach to risk stratify patients with NAFLD which should help practitioners in their management of patients with NAFLD.

Prepandemic Prevalence Estimates of Fatty Liver Disease and Fibrosis Defined by Liver Elastography in the United States

BACKGROUND AND AIMS

Fatty liver disease is a growing public health burden. We estimated prepandemic fatty liver disease prevalence determined by transient elastography-assessed hepatic steatosis and fibrosis, and examined associations with lifestyle and other factors in a United States population sample.

METHODS

Liver stiffness and controlled attenuation parameter (CAP) were assessed on 7923 non-Hispanic white, non-Hispanic black, non-Hispanic Asian, and Hispanic men and women aged 20 years and over in the National Health and Nutrition Examination Survey (NHANES) 2017-March 2020 prepandemic data.

RESULTS

The prevalence of fatty liver disease (CAP > 300 dB/m) was 28.8% and of fibrosis (liver stiffness > 8 kPa) was 10.4%. Only 7.2% of participants with fatty liver disease and 10.9% with fibrosis reported being told by a health care provider that they had liver disease. In addition to known risk factors such as metabolic factors and ALT, persons with fatty liver disease were less likely to meet physical activity guidelines, more likely to be sedentary for ≥ 12 h a day, and reported a less healthy diet. Persons with fibrosis were less likely to have a college degree and reported a less healthy diet.

CONCLUSIONS

In the U.S. population, most persons with fatty liver disease are unaware of their condition. Physical activity and dietary modifications might reduce the fatty liver disease burden. There is an urgent need for fatty liver disease management in high-risk individuals using transient elastography or other noninvasive methods to intervene in disease progression.

Nonalcoholic fatty liver disease from a primary care perspective

Nonalcoholic fatty liver disease (NAFLD) affects up to one-third of the US population. Approximately one-fifth of patients with NAFLD have nonalcoholic steatohepatitis (NASH), characterized by hepatocyte damage and inflammation with or without fibrosis. NASH leads to greater risk of liver-related complications and liver-related mortality, with the poorest outcomes seen in patients with advanced fibrosis. NASH is also associated with other metabolic comorbidities and conveys an increased risk of adverse cardiovascular outcomes and extrahepatic cancers. Despite its high prevalence, NAFLD is frequently underdiagnosed. This is a significant concern, given that early diagnosis of NAFLD is a key step in preventing progression to NASH. In this review, we describe the clinical impact of NASH from the perspective of both the clinician and the patient. In addition, we provide practical guidance on the diagnosis and management of NASH for primary care providers, who play a pivotal role in the frontline care of patients with NASH, and we use case studies to illustrate real-world scenarios encountered in the primary care setting.

Dendrobium officinale alleviates high-fat diet-induced nonalcoholic steatohepatitis by modulating gut microbiota

Introduction

The gut microbiota plays an important role in the development of nonalcoholic steatohepatitis (NASH). This study investigated the preventive effect of Dendrobium officinale (DO), including whether its effect was related to the gut microbiota, intestinal permeability and liver inflammation.

Methods

A NASH model was established in rats using a high-fat diet (HFD) and gavage with different doses of DO or Atorvastatin Calcium (AT) for 10 weeks. Body weight and body mass index along with liver appearance, weight, index, pathology, and biochemistry were measured to assess the preventive effects of DO on NASH rats. Changes in the gut microbiota were analyzed by 16S rRNA sequencing, and intestinal permeability and liver inflammation were determined to explore the mechanism by which DO treatment prevented NASH.

Results

Pathological and biochemical indexes showed that DO was able to protect rats against HFD-induced hepatic steatosis and inflammation. Results of 16S rRNA sequencing showed that Proteobacteria, Romboutsia, Turicibacter, Lachnoclostridium, Blautia, Ruminococcus_torques_group, Sutterella, Escherichia-Shigella, Prevotella, Alistipes, and Lactobacillus_acidophilus differed significantly at the phylum, genus, and species levels. DO treatment modulated the diversity, richness, and evenness of gut microbiota, downregulated the abundance of the Gram-negative bacteria Proteobacteria, Sutterella, and Escherichia-Shigella, and reduced gut-derived lipopolysaccharide (LPS) levels. DO also restored expression of the tight junction proteins, zona occludens-1 (ZO-1), claudin-1, and occludin in the intestine and ameliorated the increased intestinal permeability caused by HFD, gut microbiota such as Turicibacter, Ruminococcus, Escherichia-Shigella, and Sutterella, and LPS. Lower intestinal permeability reduced LPS delivery to the liver, thus inhibiting TLR4 expression and nuclear factor-kappaB (NF-κB) nuclear translocation, improving liver inflammation.

Discussion

These results suggest that DO may alleviate NASH by regulating the gut microbiota, intestinal permeability, and liver inflammation.

Machine learning models are superior to noninvasive tests in identifying clinically significant stages of NAFLD and NAFLD-related cirrhosis

BACKGROUND AND AIMS

We assessed the performance of machine learning (ML) models in identifying clinically significant NAFLD-associated liver fibrosis and cirrhosis.

APPROACH AND RESULTS

We implemented ML models including logistic regression (LR), random forest (RF), and artificial neural network to predict histological stages of fibrosis using 17 demographic/clinical features in 1370 patients with NAFLD who underwent liver biopsy, FibroScan, and labs within a 6-month period at multiple U.S. centers. Histological stages of fibrosis (≥F2, ≥F3, and F4) were predicted using ML, FibroScan liver stiffness measurements, and Fibrosis-4 index (FIB-4). NASH with significant fibrosis (NAS ≥ 4 + ≥F2) was assessed using ML, FibroScan-AST (FAST) score, FIB-4, and NAFLD fibrosis score (NFS). We used 80% of the cohort to train and 20% to test the ML models. For ≥F2, ≥F3, F4, and NASH + NAS ≥ 4 + ≥F2, all ML models, especially RF, had primarily higher accuracy and AUC compared with FibroScan, FIB-4, FAST, and NFS. AUC for RF versus FibroScan and FIB-4 for ≥F2, ≥F3, and F4 were (0.86 vs. 0.81, 0.78), (0.89 vs. 0.83, 0.82), and (0.89 vs. 0.86, 0.85), respectively. AUC for RF versus FAST, FIB-4, and NFS for NASH + NAS ≥ 4 + ≥F2 were (0.80 vs. 0.77, 0.66, 0.63). For NASH + NAS ≥ 4 + ≥F2, all ML models had lower/similar percentages within the indeterminate zone compared with FIB-4 and NFS. Overall, ML models performed better in sensitivity, specificity, positive predictive value, and negative predictive value compared with traditional noninvasive tests.

CONCLUSIONS

ML models performed better overall than FibroScan, FIB-4, FAST, and NFS. ML could be an effective tool for identifying clinically significant liver fibrosis and cirrhosis in patients with NAFLD.

Current Challenges and Future Direction in Surveillance for Hepatocellular Carcinoma in Patients with Nonalcoholic Fatty Liver Disease

The burden for hepatocellular carcinoma (HCC) attributed to nonalcoholic fatty liver disease (NAFLD) continues to grow in parallel with rising global trends in obesity. The risk of HCC is elevated among patients with NAFLD-related cirrhosis to a level that justifies surveillance based on cost-effectiveness argument. The quality of current evidence for HCC surveillance in all patients with chronic liver disease is poor, and even lower in those with NAFLD. For a lack of more precise risk-stratification tools, current approaches to defining a target population in noncirrhotic NAFLD are limited to noninvasive tests for liver fibrosis, as a proxy for liver-related morbidity and mortality. Beyond etiology and severity of liver disease, traditional and metabolic risk factors, such as diabetes mellitus, older age, male gender and tobacco smoking, are not enough for HCC risk stratification for surveillance efficacy and effectiveness in NAFLD. There is an association between molecular and genetic factors and HCC risk in NAFLD, and risk models integrating both clinical and genetic factors will be key to personalizing HCC risk. In this review, we discuss concerns regarding defining a target population, surveillance test accuracy, surveillance underuse, and other cost-effective considerations for HCC surveillance in individuals with NAFLD.