Infections at the nexus of metabolic-associated fatty liver disease

The association between lifelines diet score and metabolic associated fatty liver disease: a case-control study

Introduction

Adherence to a healthy dietary pattern is a fundamental recommendation for the prevention of Metabolic Associated Fatty Liver Disease (MAFLD); however, conclusive evidence regarding the optimal dietary pattern remains elusive.

Objectives

The Lifelines Diet Score (LLDS) is a novel, evidence-based scoring system designed to evaluate diet quality. However, despite the extensive research on dietary patterns and liver health, the specific relationship between the LLDS and MAFLD remains underexplored. This study aims to investigate the association between LLDS and MAFLD, providing insights into how dietary adherence, as measured by LLDS, may influence the risk and prevalence of MAFLD.

Methods

This case-control study enrolled 215 individuals who had recently been diagnosed with MAFLD and 430 healthy controls at King Khalid University Hospital. All participants were aged between 20 and 60 years, with data collection occurring from February 2023 to January 2025. The dietary intake of the participants was assessed through the utilization of a validated semi-quantitative food frequency questionnaire, which comprised a total of 168 distinct food items. Logistic regression was used to estimate the association between LLDS and MAFLD.

Results

Out of 645 participants, 215 newly diagnosed MAFLD patients and 430 healthy controls were analyzed. After stratifying participants based on LLDS tertiles, those in the highest LLDS group had a 78% lower odds of MAFLD than those in the lowest tertile (odds ratio (OR): 0.22; 95% Confidence interval (CI): 0.12-0.36, p for trend <0.001). The association remained robust even after adjustment for major confounders. These findings highlight a novel and robust association between LLDS and MAFLD, providing evidence for dietary pattern assessment in liver health research.

Conclusion

Our study strengthens the evidence that adherence to a healthy dietary pattern (as measured by LLDS) is associated with a lower MAFLD risk, even after accounting for major confounders. However, further research integrating genetic and molecular data is needed to refine personalized dietary recommendations for MAFLD prevention.

Emerging roles of cuproptosis in liver diseases

Intracellular copper levels should be maintained within a controlled range to obtain copper homeostasis. Cuproptosis, a newly discovered form of cell death, occurs when excessive copper ions bind to the lipoylated enzymes in the tricarboxylic acid cycle, which leads to lipoylated protein aggregation, proteotoxic stress, and ultimately cell death. Herein, we summarize the current knowledge regarding copper metabolism, the discovery and molecular mechanism of cuproptosis. In addition, we discuss the implications of cuproptosis in the pathogenesis of various liver diseases, including hepatocellular carcinoma (HCC), Wilson disease (WD), metabolic-associated fatty liver disease (MAFLD), liver fibrosis, hepatic ischemia-reperfusion injury (HIRI) and drug-induced liver injury (DILI). Understanding the mechanism of cuproptosis can not only provide deeper insights into the pathogenesis of liver diseases but also open up new avenues for the development of targeted therapies.

Spatial metabolomics revealed multi-organ toxicity and visualize metabolite changes induced by borneol in zebrafish

This study focuses on the potential hazards of borneol (BO) to aquatic organisms and human health. BO has antibacterial, anti-inflammatory and antioxidant activities, and is widely used in medicine, cosmetics, and detergents. In this study, zebrafish was used as a model organism to systematically evaluate the effects of BO on the heart, liver, kidney, and nervous system. The effects of BO on metabolites of zebrafish were studied using MALDI-MSI. The results showed that a high concentration of BO (500 μM) could induce morphological abnormalities (swim-bladder loss, spinal curvature, body-length shortening), cardiotoxicity (decreased heart rate, increased SV-BA distance), hepatotoxicity (reduced liver area index), and neurotoxicity (impaired behavioral ability, and dopamine neuron development deficits), but there was no renal toxicity observed in zebrafish. Additionally, MALDI-MSI analysis showed that BO exposure significantly altered the levels of metabolites, including phospholipids, fatty acids, choline, and amino acids. The contents of PC-34:1, PC-34:2, PI-36:4, PE-36:1, LysoPE-22:5, LysoPC-18:1, FA-18:2, phenylalanine, lysine and glutathione were significantly increased, while the contents of PC-38:6 and PC-40:6 were significantly decreased. Notably, BO elicited a significant alteration in the mRNA expression levels of genes associated with phospholipid metabolism, fatty acid metabolism, choline metabolism, and amino acid metabolism (such as elovl5, chpt1, chka, setd7, hgd). This study revealed that BO exerted toxicity on multiple organs and demonstrated that BO causes metabolic dysregulation in zebrafish. These findings provide a novel insight into the toxicity of BO.

Analysis of Factors Related to Pulmonary Nodules in Patients With Fatty Liver: A Large-Scale Cohort Study Based on a Physical Examination Population

Purpose

People with fatty liver are at high risk for pulmonary nodules, but the underlying mechanism is unclear. This study aimed to investigate the occurrence of lung nodules in fatty liver patients and explore influencing factors.

Patients and Methods

We retrospectively analyzed 57,119 individuals who underwent health checkups at the People's Hospital of Guangxi from May 2020 to May 2024. Patients with fatty liver were divided into pulmonary nodule and no pulmonary nodule groups. Univariate and multifactorial analyses were conducted using physical examination data, laboratory test indexes, and imaging information. Logistic regression analysis was used to identify independent predictors of pulmonary nodules in fatty liver patients.

Results

A total of 20,042 patients with fatty liver were included in the study, with 12,334 (61.5%) in the lung nodule group and 7708 (38.5%) in the non-lung nodule group. Age, gender, systolic and diastolic blood pressure were significantly higher in the pulmonary nodule group, while body weight, waist circumference, hemoglobin, uric acid, and glutamyltransferase were lower. Multifactorial logistic regression analysis showed that male gender, body weight, age, and diastolic blood pressure were significant factors influencing lung nodule development in fatty liver patients.

Conclusion

Fatty liver disease is independently associated with an increased incidence of pulmonary nodules, highlighting its importance in lung cancer screening and prevention.

Association between Helicobacter pylori infection, MASLD, and liver fibrosis in patients with severe obesity: a single-center experience

BACKGROUND AND METHODS

Our study sought to evaluate if an association exists between Helicobacter pylori (H. pylori), metabolic dysfunction- associated steatotic liver disease (MASLD), and liver fibrosis in patients with severe obesity (BMI > 35). Our retrospective study included 584 patients over the age of 18 years with severe obesity, who underwent preoperative liver transient elastography (VCTE), upper endoscopy, blood work, and intra-operative liver biopsy concurrent with bariatric surgery at a single institution from July 2020 to September 2021. Liver fibrosis scores including FIB-4, APRI, NAFLD fibrosis score, BARD score, AST: ALT ratio, and NAFLD activity score (NAS) were calculated from the laboratory results and liver biopsy findings. The presence or absence of H. pylori was determined based on gastric biopsies obtained during upper endoscopy. Other variables collected included age, gender, mean preoperative weight, BMI, and the presence or absence of comorbidities. Student's t-test and non-parametric testing were used for the analysis of continuous variables and Chi-square analysis was used for categorical data.

RESULTS

Of the 584 patients, 14.7% were H. pylori positive and 85.3% were negative. Liver fibrosis scores including FIB-4, APRI, and NAFLD fibrosis scores were significantly higher in the positive group (p < 0.05), but there was no difference in AST: ALT ratio and BARD score. A significantly higher VCTE steatosis and fibrosis scores were noted in the H. pylori-positive group (p < 0.05). Similarly, a significantly higher NAS (NAFLD activity score) on liver biopsies was noted in the positive group, with all the individual components of NAS (steatosis, lobular inflammation, and hepatocyte ballooning) being significantly higher in the positive group (p < 0.05). A significantly higher incidence of fibrosis on liver biopsies was noted in the positive group overall and across all stages of fibrosis (p < 0.05). There were no significant differences between the groups in relation to gender, mean weight, BMI, presence of comorbidities including Diabetes Mellitus, and laboratory values.

CONCLUSION

Our study demonstrates that H. pylori colonization or infection is associated with a higher risk of development of MASLD and progression to fibrosis. Further, population-based studies are needed to corroborate our findings.

Improvement of hepatic innate immunity in chemically-injured livers to develop hepatocarcinoma by a serine type-protease inhibitors enriched extract from Chenopodium quinoa

Food ingredients have critical effects on the maturation and development of the immune system, which innate - lymphoid (ILCs) and myeloid - cells play key roles as important regulators of energy storage and hepatic fat accumulation. Therefore, the objective of this study is to define potential links between a dietary immunonutritional induction of the selective functional differentiation of monocytes-derived macrophages, ILCs and lipid homeostasis in hepatocarcinoma (HCC)-developing mice. Hepatic chemically injured (diethylnitrosamine/thiacetamide) Rag2-/- and Rag2-/-Il2-/- mice were administered with serine-type protease inhibitors (SETIs) obtained from Chenopodium quinoa. Early HCC-driven immunometabolic imbalances (infiltrated macrophages, glucose homeostasis, hepatic lipid profile, ILCs expansion, inflammatory conditions, microbiota) in animals put under a high-fat diet for 2 weeks were assessed. It was also approached the potential of SETIs to cause functional adaptations of the bioenergetics of human macrophage-like cells (hMLCs) in vitro conditioning their capacity to accumulate fat. It is showed that Rag2-/-Il2-/- mice, lacking ILCs, are resistant to the SETIs-induced hepatic macrophages (CD68+F4/80+) activation. Feeding SETIs to Rag2-/- mice, carrying ILCs, promoted the expansion towards ILC3s (CD117+Nkp46+CD56+) and reduced that of ILC2s (CD117+KLRG1+) into livers. In vitro studies demonstrate that hMLCs, challenged to SETIs, develop a similar phenotype of that found in mice and bioenergetic adaptations leading to increased lipolysis. It is concluded that SETIs promote liver macrophage activation and ILCs adaptations to ameliorate HCC-driven immunometabolic imbalances.

Metabolic Dysfunction-associated Fatty Liver Disease: An Urgent Call for Global Action

There has been an exponential increase in the global prevalence of fatty liver disease in recent years in association with the obesity pandemic worldwide. 'Metabolic dysfunction-associated fatty liver disease', the new terminology adopted by an international panel of experts in 2020 to largely replace the old term 'non-alcoholic fatty liver disease', has now been accepted by most hepatologists and diabetologists across the globe. The term metabolic dysfunction-associated fatty liver disease was created to better reflect the metabolicand liver-specific manifestations and complications of fatty liver disease. It is important to disseminate our current understanding of this enigmatic disease among the global scientific fraternity. Recent publications, including articles from the latest issue of Endocrinology & Metabolism Clinics of North America, are attempting to fill this knowledge gap.

The role of mitophagy in metabolic diseases and its exercise intervention

Mitochondria are energy factories that sustain life activities in the body, and their dysfunction can cause various metabolic diseases that threaten human health. Mitophagy, an essential intracellular mitochondrial quality control mechanism, can maintain cellular and metabolic homeostasis by removing damaged mitochondria and participating in developing metabolic diseases. Research has confirmed that exercise can regulate mitophagy levels, thereby exerting protective metabolic effects in metabolic diseases. This article reviews the role of mitophagy in metabolic diseases, the effects of exercise on mitophagy, and the potential mechanisms of exercise-regulated mitophagy intervention in metabolic diseases, providing new insights for future basic and clinical research on exercise interventions to prevent and treat metabolic diseases.

Metabolic Dysfunction-Associated Fatty Liver Disease and Chronic Viral Hepatitis: The Interlink

Metabolic dysfunction-associated fatty liver disease (MAFLD) has now affected nearly one-third of the global population and has become the number one cause of chronic liver disease in the world because of the obesity pandemic. Chronic hepatitis resulting from hepatitis B virus (HBV) and hepatitis C virus (HCV) remain significant challenges to liver health even in the 21st century. The co-existence of MAFLD and chronic viral hepatitis can markedly alter the disease course of individual diseases and can complicate the management of each of these disorders. A thorough understanding of the pathobiological interactions between MAFLD and these two chronic viral infections is crucial for appropriately managing these patients. In this comprehensive clinical review, we discuss the various mechanisms of chronic viral hepatitis-mediated metabolic dysfunction and the impact of MAFLD on the progression of liver disease.

Cellular and molecular effects of fipronil in lipid metabolism of HepG2 and its possible connection to non-alcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a global public health problem that affects more than a quarter of the population. The development of this disease is correlated with metabolic dysfunctions that lead to lipid accumulation in the liver. Pesticides are one of etiologies that support NAFLD establishment. Therefore, the effects of the insecticide fipronil on the lipid metabolism of the human hepatic cell line, HepG2, was investigated, considering its widespread use in field crops and even to control domestic pests. To address the goals of the study, biochemical, cellular, and molecular analyses of different concentrations of fipronil in cell cultures were investigated, after 24 h of incubation. Relevant metabolites such as triglycerides, glucose levels, β-oxidation processes, and gene expression of relevant elements correlated with lipid and metabolism of xenobiotics were investigated. The results suggested that at 20 μM, the pesticide increased the accumulation of triglycerides and neutral lipids by reducing fatty acid oxidation and increasing de novo lipogenesis. In addition, changes were observed in genes that control oxidative stress and the xenobiotic metabolism. Together, the results suggest that the metabolic changes caused by the insecticide fipronil may be deleterious if persistent, favoring the establishment of hepatic steatosis.

Taiwan Association for the Study of the Liver-Taiwan Society of Cardiology Taiwan position statement for the management of metabolic dysfunction- associated fatty liver disease and cardiovascular diseases

Metabolic dysfunction-associated fatty liver disease (MAFLD) is an increasingly common liver disease worldwide. MAFLD is diagnosed based on the presence of steatosis on images, histological findings, or serum marker levels as well as the presence of at least one of the three metabolic features: overweight/obesity, type 2 diabetes mellitus, and metabolic risk factors. MAFLD is not only a liver disease but also a factor contributing to or related to cardiovascular diseases (CVD), which is the major etiology responsible for morbidity and mortality in patients with MAFLD. Hence, understanding the association between MAFLD and CVD, surveillance and risk stratification of MAFLD in patients with CVD, and assessment of the current status of MAFLD management are urgent requirements for both hepatologists and cardiologists. This Taiwan position statement reviews the literature and provides suggestions regarding the epidemiology, etiology, risk factors, risk stratification, nonpharmacological interventions, and potential drug treatments of MAFLD, focusing on its association with CVD.

Helicobacter infection and hepatobiliary cancer: epidemiology and pathogenesis

Hepatobiliary cancer is one of the leading causes of cancer death and a major public health problem in both developed and developing countries. Chronic infections are common risk factors for cancer. Animal studies have shown that Helicobacter pylori (H. pylori) infection can cause hepatitis, colitis, and liver cancer in susceptible individuals. Data from clinical and experimental studies point to the involvement of the gastrointestinal microbiota in the pathogenesis of the non-alcoholic fatty liver disease, including H. pylori infection. The researchers included H. pylori infection in the list of etiopathogenetic factors of primary biliary cholangitis due to the detection of its DNA in the liver tissue and antibodies to H. pylori in the bile and serum of patients with primary biliary cholangitis. A growing body of evidence suggests that H. pylori may be a risk factor for the development of liver cirrhosis and hepatocellular carcinoma in patients with viral hepatitis B and C. The contribution of H. pylori infection to the development of hepatic encephalopathy and hyperammonemia has been identified. H. pylori infection is associated with liver inflammation, fibrosis, and necrosis by inducing the synthesis of systemic inflammatory mediators and increasing intestinal permeability. Along with these consequences, bacterial translocation through the biliary tract can also lead to direct liver damage, predisposing or even triggering the carcinogenic process. The study of subspecies of Helicobacter shows that they can lead to the development of not only hepatocellular carcinoma but also other malignant neoplasms of the hepatobiliary system. This review presents current data on the epidemiology and mechanisms of the influence of H. pylori infection on malignant neoplasms of the hepatobiliary tract, with an emphasis on possible prevention strategies.

Metabolic dysfunction: The silenced connection with fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) represents a global public health burden. Despite the increase in its prevalence, the disease has not received sufficient attention compared to the associated diseases such as diabetes mellitus and obesity. In 2020 it was proposed to rename NAFLD to metabolic dysfunction-associated fatty liver disease (MAFLD) in order to recognize the metabolic risk factors and the complex pathophysiological mechanisms associated with its development. Furthermore, along with the implementation of the proposed diagnostic criteria, the aim is to address the whole clinical spectrum of the disease, regardless of BMI and the presence of other hepatic comorbidities. As would it be expected with such a paradigm shift, differing viewpoints have emerged regarding the benefits and disadvantages of renaming fatty liver disease. The following review aims to describe the way to the MAFLD from a historical, pathophysiological and clinical perspective in order to highlight why MAFLD is the approach to follow.

Periodontitis exacerbates atherosclerosis through Fusobacterium nucleatum-promoted hepatic glycolysis and lipogenesis

AIMS

Positive associations between periodontitis (PD) and atherosclerosis have been established, but the causality and mechanisms are not clear. We aimed to explore the causal roles of PD in atherosclerosis and dissect the underlying mechanisms.

METHODS AND RESULTS

A mouse model of PD was established by ligation of molars in combination with application of subgingival plaques collected from PD patients and then combined with atherosclerosis model induced by treating atheroprone mice with a high-cholesterol diet (HCD). PD significantly aggravated atherosclerosis in HCD-fed atheroprone mice, including increased en face plaque areas in whole aortas and lesion size at aortic roots. PD also increased circulating levels of triglycerides and cholesterol, hepatic levels of cholesterol, and hepatic expression of rate-limiting enzymes for lipogenesis. Using 16S ribosomal RNA (rRNA) gene sequencing, Fusobacterium nucleatum was identified as the most enriched PD-associated pathobiont that is present in both the oral cavity and livers. Co-culture experiments demonstrated that F. nucleatum directly stimulated lipid biosynthesis in primary mouse hepatocytes. Moreover, oral inoculation of F. nucleatum markedly elevated plasma levels of triglycerides and cholesterol and promoted atherogenesis in HCD-fed ApoE-/- mice. Results of RNA-seq and Seahorse assay indicated that F. nucleatum activated glycolysis, inhibition of which by 2-deoxyglucose in turn suppressed F. nucleatum-induced lipogenesis in hepatocytes. Finally, interrogation of the molecular mechanisms revealed that F. nucleatum-induced glycolysis and lipogenesis by activating PI3K/Akt/mTOR signalling pathway in hepatocytes.

CONCLUSIONS

PD exacerbates atherosclerosis and impairs lipid metabolism in mice, which may be mediated by F. nucleatum-promoted glycolysis and lipogenesis through PI3K/Akt/mTOR signalling in hepatocytes. Treatment of PD and specific targeting of F. nucleatum are promising strategies to improve therapeutic effectiveness of hyperlipidaemia and atherosclerosis.

HELICOBACTER AND HEPATOBILIARY DISEASES: UPDATE 2023

•Clinical studies have shown that hepatobiliary diseases of inflammatory and neoplastic origin are associated with Helicobacter infection. •Translocation and the ascending pathway are putative mechanisms for Helicobacter spp to enter the hepatobiliary system. •H. pylori infection has a systemic effect through the activity of pro-inflammatory cytokines, TNF-α, leukotrienes, interferon-β, interferon-γ, and acute phase proteins. •Histopathological confirmation is needed to present that H. pylori eradication prevents or improves hepatobiliary disease progression. Helicobacter Pylori (H. pylori) is one of the main infectious causes of gastroduodenal diseases, however, its role in developing different extragastric diseases has been proven. The possible involvement of H. pylori in the pathogenesis of cardiovascular, metabolic, neurodegenerative, skin, and hepatobiliary diseases is suggested. The bacterium has been found in tissue samples from the liver, biliary tract, and gallstones of animals and humans. However, the role of H. pylori infection in the pathogenesis of liver and biliary diseases has not been finally established. The histopathological confirmation of the positive effect of H. pylori eradication is needed. In addition, there are discussions on the clinical significance of other Helicobacter species. The review presents the data available for and against the involvement of H. pylori in hepatobi-liary disease development and progression.

Progress in understanding of association between metabolic associated fatty liver disease and viral infectious diseases

Metabolic associated fatty liver disease (MAFLD) is a chronic liver disease with the highest incidence in the world, which affects 1/4-1/3 of the world population and has a serious effect on people's health. As is a multi-systemic disease, MAFLD is closely related to the occurrence and prognosis of many diseases. Studies have shown that MAFLD is associated with viral infectious diseases, and their interaction affects the prognosis of the disease. This paper reviews the research progress in this field in recent years.

The gut microbiota - a vehicle for the prevention and treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) arises principally against a background of cirrhosis and these two diseases are responsible globally for over 2 million deaths a year. There are few treatment options for liver cirrhosis and HCC, so it is vital to arrest these pathologies early in their development. To do so, we propose dietary and therapeutic solutions that involve the gut microbiota and its consequences. Integrated dietary, environmental and intrinsic signals result in a bidirectional connection between the liver and the gut with its microbiota, known as the gut-liver axis. Numerous lifestyle factors can result in dysbiosis with a change in the functional composition and metabolic activity of the microbiota. A panoply of metabolites can be produced by the microbiota, including ethanol, secondary bile acids, trimethylamine, indole, quinolone, phenazine and their derivatives and the quorum sensor acyl homoserine lactones that may contribute to HCC but have yet to be fully investigated. Gram-negative bacteria can activate the pattern recognition receptor toll-like receptor 4 (TLR4) in the liver leading to nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, which can contribute to HCC initiation and progression. The goal in preventing HCC should be to ensure a healthy gut microbiota using probiotic supplements containing beneficial bacteria and prebiotic plant fibers such as oligosaccharides that stimulate their growth. The clinical development of TLR4 antagonists is urgently needed to counteract the pathological effects of dysbiosis on the liver and other organs. Further nutrigenomic studies are required to understand better how the diet influences the gut microbiota and its adverse effects on the liver.

Metabolic-Associated Fatty Liver Disease Is Highly Prevalent in the Postacute COVID Syndrome

BACKGROUND

A proposal has recently been advanced to change the traditional definition of nonalcoholic fatty liver disease to metabolic-associated fatty liver disease (MAFLD), to reflect the cluster of metabolic abnormalities that may be more closely associated with cardiovascular risk. Long coronavirus disease 2019 (COVID-19) is a smoldering inflammatory condition, characterized by several symptom clusters. This study aims to determine the prevalence of MAFLD in patients with postacute COVID syndrome (PACS) and its association with other PACS-cluster phenotypes.

METHODS

We included 235 patients observed at a single university outpatient clinic. The diagnosis of PACS was based on ≥1 cluster of symptoms: respiratory, neurocognitive, musculoskeletal, psychological, sensory, and dermatological. The outcome was prevalence of MAFLD detected by transient elastography during the first postdischarge follow-up outpatient visit. The prevalence of MAFLD at the time of hospital admission was calculated retrospectively using the hepatic steatosis index.

RESULTS

Of 235 patients, 162 (69%) were men (median age 61). The prevalence of MAFLD was 55.3% at follow-up and 37.3% on admission (P < .001). Insulin resistance (odds ratio [OR] = 1.5; 95% confidence interval [CI], 1.14-1.96), body mass index (OR = 1.14; 95% CI, 1.04-1.24), and the metabolic syndrome (OR = 2.54; 95% CI, 1.13-5.68) were independent predictors of MAFLD. The number of PACS clusters was inversely associated with MAFLD (OR = 0.86; 95% CI, .76-0.97). Thirty-one patients (13.2%) had MAFLD with no other associated PACS clusters. All correlations between MAFLD and other PACS clusters were weak.

CONCLUSIONS

Metabolic-associated fatty liver disease was highly prevalent after hospital discharge and may represent a specific PACS-cluster phenotype, with potential long-term metabolic and cardiovascular health implications.

From NAFLD to MAFLD: Aligning Translational In Vitro Research to Clinical Insights

Although most same-stage non-alcoholic fatty liver disease (NAFLD) patients exhibit similar histologic sequelae, the underlying mechanisms appear to be highly heterogeneous. Therefore, it was recently proposed to redefine NAFLD to metabolic dysfunction-associated fatty liver disease (MAFLD) in which other known causes of liver disease such as alcohol consumption or viral hepatitis do not need to be excluded. Revised nomenclature envisions speeding up and facilitating anti-MAFLD drug development by means of patient stratification whereby each subgroup would benefit from distinct pharmacological interventions. As human-based in vitro research fulfils an irrefutable step in drug development, action should be taken as well in this stadium of the translational path. Indeed, most established in vitro NAFLD models rely on short-term exposure to fatty acids and use lipid accumulation as a phenotypic benchmark. This general approach to a seemingly ambiguous disease such as NAFLD therefore no longer seems applicable. Human-based in vitro models that accurately reflect distinct disease subgroups of MAFLD should thus be adopted in early preclinical disease modeling and drug testing. In this review article, we outline considerations for setting up translational in vitro experiments in the MAFLD era and allude to potential strategies to implement MAFLD heterogeneity into an in vitro setting so as to better align early drug development with future clinical trial designs.