From nonalcoholic steatohepatitis, metabolic dysfunction-associated fatty liver disease, to steatotic liver disease: Updates of nomenclature and impact on clinical trials

Mitochondrial mt12361A>G increased risk of metabolic dysfunction-associated steatotic liver disease among non-diabetes

BACKGROUND

Insulin resistance, lipotoxicity, and mitochondrial dysfunction contribute to the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD). Mitochondrial dysfunction impairs oxidative phosphorylation and increases reactive oxygen species production, leading to steatohepatitis and hepatic fibrosis. Artificial intelligence (AI) is a potent tool for disease diagnosis and risk stratification.

AIM

To investigate mitochondrial DNA polymorphisms in susceptibility to MASLD and establish an AI model for MASLD screening.

METHODS

Multiplex polymerase chain reaction was performed to comprehensively genotype 82 mitochondrial DNA variants in the screening dataset (n = 264). The significant mitochondrial single nucleotide polymorphism was validated in an independent cohort (n = 1046) using the Taqman® allelic discrimination assay. Random forest, eXtreme gradient boosting, Naive Bayes, and logistic regression algorithms were employed to construct an AI model for MASLD.

RESULTS

In the screening dataset, only mt12361A>G was significantly associated with MASLD. mt12361A>G showed borderline significance in MASLD patients with 2-3 cardiometabolic traits compared with controls in the validation dataset (P = 0.055). Multivariate regression analysis confirmed that mt12361A>G was an independent risk factor of MASLD [odds ratio (OR) = 2.54, 95% confidence interval (CI): 1.19-5.43, P = 0.016]. The genetic effect of mt12361A>G was significant in the non-diabetic group but not in the diabetic group. mt12361G carriers had a 2.8-fold higher risk than A carriers in the non-diabetic group (OR = 2.80, 95%CI: 1.22-6.41, P = 0.015). By integrating clinical features and mt12361A>G, random forest outperformed other algorithms in detecting MASLD [training area under the receiver operating characteristic curve (AUROC) = 1.000, validation AUROC = 0.876].

CONCLUSION

The mt12361A>G variant increased the severity of MASLD in non-diabetic patients. AI supports the screening and management of MASLD in primary care settings.

Cardiovascular Risk From Metabolic Dysfunction-Associated Steatotic Liver Disease, Cardiometabolic Risk Factor Count, and Their Longitudinal Changes: A Nationwide Cohort Study

INTRODUCTION

Metabolic dysfunction-associated steatotic liver disease (MASLD) is associated with incident cardiovascular disease (CVD). However, CVD risk could vary across and within individuals with MASLD. We investigated the cardiovascular implications of MASLD, cardiometabolic risk factor count, and their longitudinal changes.

METHODS

From nationwide health screening data, we included adults aged 20-79 years without increased/excessive alcohol intake, concomitant liver diseases, and prior CVD at baseline examination in 2009 (N = 7,292,497). Participants were classified according to MASLD status; those with MASLD were further categorized by their count of qualifying cardiometabolic risk factors (1-5). Individuals who underwent follow-up examinations in 2011 (N = 4,198,672) were additionally classified according to their baseline and follow-up MASLD status; those with persistent MASLD were further categorized by combination of baseline and follow-up cardiometabolic risk factor counts. The risk of incident CVD was assessed using multivariable-adjusted Cox model.

RESULTS

Over a median follow-up of 12.3 years, 220,088 new CVD events occurred. The presence of MASLD was associated with higher incidence of CVD. Among participants with MASLD, the risk of CVD increased gradually with higher cardiometabolic risk factor count (per 1-higher; hazard ratio [HR] 1.18, 95% confidence interval [CI] 1.18-1.19). The development of MASLD during follow-up was associated with higher risk of CVD (HR 1.28, 95% CI 1.25-1.31), whereas the regression of MASLD was associated with lower risk of CVD (HR 0.84, 95% CI 0.82-0.86). Among individuals with persistent MASLD, gaining and losing cardiometabolic risk factor count during follow-up were associated with elevated and reduced risk of CVD, respectively.

DISCUSSION

MASLD status, cardiometabolic risk factor count, and their longitudinal changes were all associated with the risk of incident CVD. Accurate identification of these markers may facilitate personalized management of MASLD-related CVD risk.

Collagen-rich liver-derived extracellular matrix hydrogels augment survival and function of primary rat liver sinusoidal endothelial cells and hepatocytes

Liver sinusoidal endothelial cells (LSECs) are key targets for addressing metabolic dysfunction-associated steatotic liver disease (MASLD). However, isolating and culturing primary LSECs is challenging due to rapid dedifferentiation, resulting in loss of function. The extracellular matrix (ECM) likely plays a crucial role in maintaining the fate and function of LSECs. In this study, we explored the influence of liver-ECM (L-ECM) on liver cells and developed culture conditions that maintain the differentiated function of liver cells in vitro for prolonged periods. Porcine liver-derived L-ECM, containing 34.9 % protein, 0.045 % glycosaminoglycans, and negligible residual DNA (41.2 ng/mg), was utilized to culture primary rat liver cells in generated hydrogels. Proteomic analyses and molecular weight distribution of proteins of solubilized L-ECM revealed the typical diverse ECM core matrisome, with abundant collagens. L-ECM hydrogels showed suitable stiffness and stress relaxation properties. Furthermore, we demonstrated that collagen-rich L-ECM hydrogels enhanced LSECs' and hepatocytes' viability, and reduced the dedifferentiation rate of LSECs. In addition, hepatocyte function was maintained longer by culture on L-ECM hydrogels compared to traditional culturing. These beneficial effects are likely attributed to the bioactive macromolecules including collagens, and mechanical and microarchitectural properties of the L-ECM hydrogels.

Dual-etiology MAFLD: the interactions between viral hepatitis B, viral hepatitis C, alcohol, and MAFLD

Metabolic dysfunction-associated fatty liver disease (MAFLD) and viral hepatitis due to chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection are common liver diseases worldwide. Excessive alcohol consumption and alcoholic liver disease (ALD) are also emerging health problems. Therefore, in clinical practice, we may encounter subjects with dual etiology of liver diseases such as coexisting MAFLD/HBV, MAFLD/HCV, and MAFLD/ALD. In this review, we summarize the epidemiology, clinical features, and mutual interactions of MAFLD with coexisting HBV, HCV, or ALD. The impact of MAFLD on the progression of liver diseases and treatment outcomes in patients with chronic viral hepatitis and the clinical questions to be addressed regarding dual MAFLD and ALD are also discussed.

TM7SF3 controls TEAD1 splicing to prevent MASH-induced liver fibrosis

The mechanisms of hepatic stellate cell (HSC) activation and the development of liver fibrosis are not fully understood. Here, we show that deletion of a nuclear seven transmembrane protein, TM7SF3, accelerates HSC activation in liver organoids, primary human HSCs, and in vivo in metabolic-dysfunction-associated steatohepatitis (MASH) mice, leading to activation of the fibrogenic program and HSC proliferation. Thus, TM7SF3 knockdown promotes alternative splicing of the Hippo pathway transcription factor, TEAD1, by inhibiting the splicing factor heterogeneous nuclear ribonucleoprotein U (hnRNPU). This results in the exclusion of the inhibitory exon 5, generating a more active form of TEAD1 and triggering HSC activation. Furthermore, inhibiting TEAD1 alternative splicing with a specific antisense oligomer (ASO) deactivates HSCs in vitro and reduces MASH diet-induced liver fibrosis. In conclusion, by inhibiting TEAD1 alternative splicing, TM7SF3 plays a pivotal role in mitigating HSC activation and the progression of MASH-related fibrosis.

Impact of MAFLD criteria on postoperative recurrence of non-B, non-C HCC

BACKGROUND

This study aimed to clarify the population in whom the presence of metabolic dysfunction-associated fatty liver disease (MAFLD) especially contributes to recurrence after liver resection for non-B, non-C hepatocellular carcinoma (NBNC-HCC).

METHODS

Of the 199 patients who underwent liver resection for NBNC-HCC, those who exceeded Milan criteria and with pathologically proven vascular invasion, intrahepatic metastasis, and positive resection margins were excluded, and the remaining 94 were eligible for this study. We explored factors contributing to postoperative recurrence in populations with and without advanced liver fibrosis.

RESULTS

Independent factors contributing to postoperative recurrence in the study population were male sex ( P  = 0.023) and presence of type 2 diabetes (DM) ( P  = 0.006) and advanced liver fibrosis ( P  < 0.001). Factors in cases with advanced liver fibrosis (n = 43) were non-overweight ( P  = 0.02), type 2 DM ( P  = 0.006), and preoperative alpha-fetoprotein level of 8.2 ng/ml or higher ( P  = 0.021). In cases without advanced liver fibrosis (n = 51), only presence of all three MAFLD criteria was related to recurrence.

CONCLUSION

Liver fibrosis is a strong factor contributing to postoperative recurrence of NBNC-HCC, as previously reported. In patients with advanced liver fibrosis, presence of type 2 DM was the only factor associated with recurrence among MAFLD criteria. On the other hand, in patients without advanced liver fibrosis, the combination of all MAFLD criteria, rather than a specific criterion alone, contributed to recurrence. MAFLD criteria were found to have utility as predictors of postoperative recurrence in NBNC-HCC.

From Nonalcoholic Fatty Liver Disease to Metabolic Dysfunction-Associated Steatotic Liver Disease: Out with the Old, in with the New

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease (CLD) affecting a quarter of the global population [...].

Gut microbiota-derived indole compounds attenuate metabolic dysfunction-associated steatotic liver disease by improving fat metabolism and inflammation

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease, and its prevalence has increased worldwide in recent years. Additionally, there is a close relationship between MASLD and gut microbiota-derived metabolites. However, the mechanisms of MASLD and its metabolites are still unclear. We demonstrated decreased indole-3-propionic acid (IPA) and indole-3-acetic acid (IAA) in the feces of patients with hepatic steatosis compared to healthy controls. Here, IPA and IAA administration ameliorated hepatic steatosis and inflammation in an animal model of WD-induced MASLD by suppressing the NF-κB signaling pathway through a reduction in endotoxin levels and inactivation of macrophages. Bifidobacterium bifidum metabolizes tryptophan to produce IAA, and B. bifidum effectively prevents hepatic steatosis and inflammation through the production of IAA. Our study demonstrates that IPA and IAA derived from the gut microbiota have novel preventive or therapeutic potential for MASLD treatment.