Nonalcoholic fatty liver disease

The role of cytokines as predictors for NAFLD-related diseases: A bidirectional Mendelian randomization study

BACKGROUND

Prior research has highlighted associations between inflammatory cytokines and non-alcoholic fatty liver disease (NAFLD), but causal relationships remain unclear. Employing the Mendelian randomization (MR) approach, this investigation aims to explore the connection between 41 inflammatory cytokines and NAFLD-related diseases.

METHODS

Our research implemented bidirectional study focusing on 41 cytokines in 8,293 Finns, predicting genetic associations with NAFLD, nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. We primarily utilized the inverse variance weighted (IVW) method to evaluate the bidirectional relationships. Additionally, a sensitivity analysis was carried out to ensure the reliability of our findings.

RESULTS

An elevated risk for NAFLD was correlated with both IL-2 (OR = 1.226, 95 % CI = 1.018-1.477, p = 0.031) and TNF-β (OR = 1.151, 95 % CI = 1.011-1.310, p = 0.033). IL-16 is associated with decreased NAFLD risk (OR = 0.820, 95 % CI = 0.719-0.934, p = 0.033). β-NGF (OR = 2.495, 95 % CI = 1.019-6.108, p = 0.045) and SCGFβ (OR = 1.541, 95 % CI = 1.052-2.256, p = 0.026) are linked to higher NASH risk. No significant associations were found for fibrosis and cirrhosis. Furthermore, the causal relationship between genetic predisposition to NAFLD-related diseases and various inflammatory cytokines was established.

CONCLUSIONS

Our MR analysis identifies specific cytokines as genetic predictors for NAFLD and NASH. IL-2 and TNF-β increase NAFLD risk, IL-16 appears protective, and β-NGF and SCGFβ are associated with greater NASH risk. These insights are crucial for understanding the etiology and treatment of NAFLD-related diseases.

Loss of mitochondrial amidoxime-reducing component 1 (mARC1) prevents disease progression by reducing fibrosis in multiple mouse models of chronic liver disease

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease is a prevalent disease that affects nearly one-third of the global population. Recent genome-wide association studies revealed that a common missense variant in the gene encoding mitochondrial amidoxime reducing component 1 (mARC1) is associated with protection from metabolic dysfunction-associated steatotic liver disease, all-cause cirrhosis, and liver-related mortality suggesting a role for mARC1 in liver pathophysiology; however, little is known about its function in the liver. In this study, we aimed to evaluate the impact of mARC1 hepatoprotective variants on protein function, the effect of loss of mARC1 on cellular lipotoxic stress response, and the effect of global or hepatocyte-specific loss of mARC1 in various mouse models of metabolic dysfunction-associated steatohepatitis and liver fibrosis.

METHODS AND RESULTS

Expression and characterization of mARC1 hepatoprotective variants in cells and mouse liver revealed that the mARC1 p.A165T exhibited lower protein levels but maintained its mitochondrial localization. In cells, the knockdown of mARC1 improved cellular bioenergetics and decreased mitochondrial superoxide production in response to lipotoxic stress. Global genetic deletion and hepatocyte-specific knockdown of mARC1 in mice significantly reduced liver steatosis and fibrosis in multiple mouse models of metabolic dysfunction-associated steatohepatitis and liver fibrosis. Furthermore, RNA-seq analysis revealed that the pathways involved in extracellular matrix remodeling and collagen formation were downregulated in the liver, and the plasma lipidome was significantly altered in response to the loss of mARC1 in mice.

CONCLUSIONS

Overall, we have demonstrated that loss of mARC1 alters hepatocyte response to lipotoxic stress and protects mice from diet-induced MASH and liver fibrosis consistent with findings from human genetics.

The Proteomics of MASLD Progression: Insights From Functional Analysis to Drive the Development of New Therapeutic Solutions

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the leading chronic liver disease worldwide, with alarming prevalence reaching epidemic proportions.

AIMS AND METHODS

The objective of this study is to provide a comprehensive review of the latest blood proteomics studies on MASLD and metabolic dysfunction-associated steatohepatitis (MASH), with emphasis on fibrosis. Furthermore, our objective is to conduct an analysis of protein pathways and interactions by integrating proteomics data using functional enrichment analysis of the deregulated proteins.

RESULTS

Notwithstanding the considerable discrepancies in the methodology and the number of proteins examined in the circulation, the analysis reveals a consistent pattern among the list of proteins that are decreased or increased in the blood of the affected patients. The relevant biological processes (BP) associated with down- and upregulated proteins are high-density lipoprotein remodelling and complement activation, respectively. The protein families identified include not only those expected to be involved in the immune system and cell adhesion and migration but also ligands of glycoproteins expressed in cells that have been subjected to stress and proteins containing the Sushi domain.

CONCLUSIONS

The application of cutting-edge methodologies to investigate the blood proteome in MASH is yielding insights that facilitate the elucidation of disease mechanisms and the identification of optimal noninvasive biomarkers. However, several challenges remain to be addressed in future research, including the generalisation of results on a global scale, the optimisation of analytical technologies and the implementation of large longitudinal studies to gain insights into the molecular mechanisms that underpin the development of advanced disease.

New advances in novel pharmacotherapeutic candidates for the treatment of metabolic dysfunction-associated steatohepatitis (MASH) between 2022 and 2024

Metabolic dysfunction-associated steatotic liver disease (MASLD) covers a broad spectrum of profile from simple fatty liver, evolving to metabolic dysfunction-associated steatohepatitis (MASH), to hepatic fibrosis, further progressing to cirrhosis and hepatocellular carcinoma (HCC). MASLD has become a prevalent disease with 25% in average over the world. MASH is an active stage, and requires pharmacological intervention when there is necroptotic damage with fibrotic progression. Although there is an increased understanding of MASH pathogenesis and newly approved resmetirom, given its complexity and heterogeneous pathophysiology, there is a strong necessity to develop more drug candidates with better therapeutic efficacy and well-tolerated safety profile. With an increased list of pharmaceutical candidates in the pipeline, it is anticipated to witness successful approval of more potential candidates in this fast-evolving field, thereby offering different categories of medications for selective patient populations. In this review, we update the advances in MASH pharmacotherapeutics that have completed phase II or III clinical trials with potential application in clinical practice during the latest 2 years, focusing on effectiveness and safety issues. The overview of fast-evolving status of pharmacotherapeutic candidates for MASH treatment confers deep insights into the key issues, such as molecular targets, endpoint selection and validation, clinical trial design and execution, interaction with drug administration authority, real-world data feedback and further adjustment in clinical application.

Magnitude, patterns, and factors associated with liver disease among clinically suspected clients in Eastern Ethiopia: hidden public health tragedy

BACKGROUND

Liver diseases are a public health problem in developing regions, and the majority of them are asymptomatic. Evidence on the current burden of liver disease and associated context-specific risk factors is scarce in the study area, where various risk factors for liver disease, including khat chewing, smoking, and aflatoxin exposure, are common. This study was to assess the magnitude, patterns, and factors associated with liver disease among patients visiting governmental hospitals in eastern Ethiopia.

METHODS

A facility-based cross-sectional study was conducted among randomly selected 388 clinically suspected adults for liver disease visiting a public hospital in Dire Dawa, Ethiopia. Data was collected using a combination of structured questionnaires, physical examinations, and investigations through interviews, medical chart reviews, liver enzymes, and the results of ultrasound examinations. Bivariable and multivariable logistic regression analyses were employed to determine the factors associated with liver disease. Candidate variables in bivariable analysis were selected based on p-values < 0.25, biological plausibility, and evidence of associations from previous studies. The level of significance was considered at a P-value < 0.05, and the adjusted odds ratio with a 95% confidence interval was reported.

RESULTS

A total of 388 (92%) adults were included and liver disease was diagnosed among 295 (76%; 71.5-80.2) of the study participants, where chronic liver disease due to non-viral (65.1%) and viral causes (34.9%) were prevalent. The risk of liver disease was higher among females (AOR = 3.43; 1.80-6.55) and under grade twelve (AOR = 3.90; 1.95-7.82) compared to counterparts. Furthermore, alcohol consumption (AOR = 3.14; 1.33-7.32), khat chewing (AOR = 1.69; 0.91-3.15), a history of hospitalization (AOR = 4.20; 2.29-7.11), and a history of intestinal parasite infection (AOR = 1.17; 0.55-2.49) were found to be positively associated with an increased risk of liver disease among adults.

CONCLUSIONS

Liver disease detection rate was found to be high and could be associated with substance use (alcohol and khat), history of hospitalization, and worm infection, which can be incorporated into the prevention strategies of liver diseases.

Effects of ultra-processed foods on the liver: insights from gut microbiome and metabolomics studies in rats

Purpose

High consumption of Ultra-processed foods (UPF) have been identified as a potential risk factor for Non-alcoholic fatty liver disease (NAFLD). Nevertheless, there is limited empirical evidence regarding the impact of UPF, which are typical combination of processed foods, on liver health through alterations in gut microbiota and metabolic processes. We aim to examine the potential impact of UPF on liver health and to explore the role of gut microbiota and metabolites.

Methods

This study used Sprague-Dawley rats to mimic modern UPF diets for 90 days. Some serum biochemical indices, inflammatory factors, oxidative stress markers, hematoxylin-eosin (HE) staining of the liver, 16S ribosomal RNA (rRNA) and Liquid chromatography-mass spectrometry (LC-MS) of rat feces were detected.

Results

The UPF diet-induced simple steatosis of the liver in rats without affecting the levels of IL-6, GSH, MDA, and SOD. Additionally, it modified the gut microbiota, increasing potentially harmful bacteria, such as norank_f__Desulfovibrionaceae and Staphylococcus, while also elevating the relative abundance of potentially beneficial bacteria, including Dubosiella and Allobaculum. Furthermore, the consumption of UPF led to a metabolomic disorder characterized by disruptions in the sphingolipid signaling pathway, sulfur relay system, and arachidonic acid metabolism.

Conclusion

In conclusion, the findings of this study indicate that the consumption of UPF influences the development of simple hepatic steatosis, potentially through alterations in gut microbiota and metabolomics.

Dimeric guaianolide sesquiterpenoids from the flowers of Chrysanthemum indicum ameliorate hepatic steatosis through mitigating SIRT1-mediated lipid accumulation and ferroptosis

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) acts as the primary contributor to non-alcoholic steatohepatitis, fibrosis, cirrhosis, and potentially hepatocellular carcinoma. The flowers of Chrysanthemum indicum, a traditional edible medicinal herb, have been widely used in China for more than 2000 years. However, the function of C. indicum in managing NAFLD has seldom been investigated.

OBJECTIVES

To reveal the novel active components and underlying mechanisms of C. indicum in treating NAFLD.

METHODS

An MS/MS-based molecular networking-guided strategy was used for the chemical investigation. The structure identification of the new compounds involved high resolution electrospray ionization mass spectrometry (HRESIMS), 1D and 2D nuclear magnetic resonance (NMR) spectra, electronic circular dichroism (ECD), and X-ray crystallographic analysis. The biological evaluation was performed using Nile Red staining, flow cytometry, commercial kits, western blotting, co-immunoprecipitation, isothermal titration calorimetry, cellular thermal shift assay, drug affinity responsive target stability assay, molecular docking, and confocal immunofluorescence.

RESULTS

A total of 27 new dimeric sesquiterpenoids, chryindicolides A-Z (1-26) and chrysanthemolide C (27), together with seven known compounds, were isolated from the flowers of C. indicum under the guide of MS/MS-based molecular networking. Among them, compounds 1-7 were rare chlorine-containing guaianolide dimers. Chryindicolide O (15) directly bound and activated the deacetylase Sirtuin 1 (SIRT1) to reduce de novo lipogenesis, enhance fatty acid β-oxidation, and inhibit ferroptosis in palmitic acid and oleic acid (P/O)-induced AML12 hepatocytes. In addition, chryindicolide O significantly ameliorated liver steatosis in high-fat diet-fed zebrafish.

CONCLUSION

Novel guaianolide dimers from C. indicum alleviated hepatic steatosis through mitigating SIRT1-mediated lipid accumulation and ferroptosis, suggesting that they could be further developed as candidates against NAFLD.

Diagnostic Utility of Serum Ferritin in Identifying Liver Fibrosis in Patients with Non-Alcoholic Fatty Liver Disease (NAFLD): A Cross-Sectional Study Using National Health and Nutrition Examination Survey (NHANES-2017-2020) Data

Non-alcoholic fatty liver disease (NAFLD) is one of the major causes of chronic liver disease worldwide. There are conflicting reports on the association of serum ferritin levels and its utility in discriminating various stages of liver fibrosis in patients with NAFLD. This study is done to address the conflicts by analysing the National Health and Nutritional Examination Survey 2017-2020 (NHANES 2017-2020) data. The survey data was screened, and the eligible participants (n = 5901) were categorized based on the controlled attenuation parameter (CAP) obtained from Vibration Controlled and Transient Elastography (VCTE) scan into 2 groups, NAFLD (CAP ≥ 274 dB/m, n = 2528) and non-NAFLD (CAP < 274 dB/m, n = 3373). The NAFLD group had a significantly higher proportion of obese, diabetic, and metabolic syndrome participants. Serum ferritin levels were significantly higher in the NAFLD group, and the levels showed an upward trend from simple steatosis to significant fibrosis. Multivariate regression analysis showed that ferritin has a significant positive association with the median liver stiffness parameter (LSM), which is the index of liver fibrosis. Receiver operator characteristic curve (ROC) analysis showed that serum ferritin levels are a poor predictor of fibrosis (LSM > 8 kPA) in those with NAFLD (AUC = 0.59, Sensitivity = 53.5%, Specificity = 60.3%). To conclude, serum ferritin levels were positively associated and it trended upward as the disease progressed from simple steatosis to fibrosis in NAFLD. However, its diagnostic utility in discriminating liver fibrosis in patients with NAFLD is limited.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12291-023-01159-8.

Rodent model of metabolic dysfunction-associated fatty liver disease: a systematic review

Although significant progress has been made in developing preclinical models for metabolic dysfunction-associated steatotic liver disease (MASLD), few have encapsulated the essential biological and clinical outcome elements reflective of the human condition. We conducted a comprehensive literature review of English-language original research articles published from 1990 to 2023, sourced from PubMed, Embase, and Web of Science, aiming to collate studies that provided a comparative analysis of physiological, metabolic, and hepatic histological characteristics between MASLD models and control groups. The establishment of a robust metabolic dysfunction-associated steatotic liver rodent model hinges on various factors, including animal species and strains, sex, induction agents and methodologies, and the duration of induction. Through this review, we aim to guide researchers in selecting suitable induction methods and animal species for constructing preclinical models aligned with their specific research objectives and laboratory conditions. Future studies should strive to develop simple, reliable, and reproducible models, considering the model's sensitivity to factors such as light-dark cycles, housing conditions, and environmental temperature. Additionally, the potential of diverse in vitro models, including 3D models and liver organ technology, warrants further exploration as valuable tools for unraveling the cellular mechanisms underlying fatty liver disease.

Metabolic dysfunction-associated steatotic liver disease exhibits sex-specific microbial heterogeneity within intestinal compartments

BACKGROUND/AIMS

Evidence suggests that the gastrointestinal microbiome plays a significant role in the biology of metabolic dysfunction-associated steatotic liver disease (MASLD). However, it remains unclear whether disparities in the gut microbiome across intestinal tissular compartments between the sexes lead to MASLD pathogenesis.

METHODS

Sex-specific analyses of microbiome composition in two anatomically distinct regions of the gut, the small intestine and colon, were performed using an experimental model of MASLD. The study involved male and female spontaneously hypertensive rats and the Wistar-Kyoto control rat strain, which were fed either a standard chow diet or a high-fat diet for 12 weeks to induce MASLD (12 rats per group). High-throughput 16S sequencing was used for microbiome analysis.

RESULTS

There were significant differences in the overall microbiome composition of male and female rats with MASLD, including variations in topographical gut regions. The beta diversity of the jejunal and colon microbiomes was higher in female rats than in male rats (PERMANOVA p-value=0.001). Sex-specific analysis and discriminant features using LEfSe showed considerable variation in bacterial abundance, along with distinct functional properties, in the jejunum and colon of animals with MASLD. Significantly elevated levels of lipopolysaccharide and protein expression of Toll-like receptor 4 were observed in the livers of male rats with MASLD compared with their female counterparts.

CONCLUSION

This study uncovered sexual dimorphism in the gut microbiome of MASLD and identified microbial heterogeneity within intestinal compartments. Insights into sex-specific variations in gut microbiome composition could facilitate customised treatment strategies.

Natural disease course of chronic visceral acid sphingomyelinase deficiency in adults: A first step toward treatment criteria

Acid sphingomyelinase deficiency (ASMD) is an ultra-rare lysosomal storage disease with a broad spectrum of manifestations ranging from severe neuropathic forms to attenuated, chronic visceral forms. Manifestations of the chronic visceral subtype are variable and encompass different degrees of hepatosplenomegaly, pulmonary disease and dyslipidemia. The aim of this study was to provide insights into the natural course of adult patients with the chronic visceral subtype. Based on these insights, we proposed tentative criteria for initiation and follow-up of enzyme replacement therapy (ERT). The data of 23 adult patients were collected in a prospective study. Clinical, genetic and demographic data, plasma measurements, abdominal imaging, pulmonary imaging, pulmonary function tests and quality of life questionnaires were collected. Stability of disease based on several clinical, biochemical and radiological markers (i.e., spleen volume, platelet levels, liver volume, alanine aminotransferase [ALT] levels, diffusion capacity of the lungs for carbon monoxide [DLCO] chitotriosidase activity and lysosphingomyelin [LSM]) was assessed. Cardiovascular risk was estimated based on sex, age, smoking, systolic blood pressure and lipid profile. Quality of life was evaluated with the 36-Item Short Form Health Survey and the Health Assessment Questionnaire. Median follow-up was 6.1 years (range 1.3-19.5 years). The most common manifestations were splenomegaly (100%), decreased high-density lipoprotein cholesterol (HDL-C) plasma levels (83%), (signs of) steatosis measured with transient elastography (82%), thrombocytopenia (64%), hepatomegaly (52%) and decreased diffusion capacity (45%). The majority of markers remained stable during follow-up. Twelve patients showed progression of disease: four for spleen volume, two for liver volume, three for DLCO, seven for chitotriosidase activity and three for LSM. One patient showed progression of disease based on four markers, although this patient did not report any problems at the last visit. Cardiovascular risk was estimated and was increased in half of the patients older than 40 years. Patient-reported quality of life did not differ from the general population, but differences in median 36-Item Short Form Health Survey (SF-36) scores of patients with severe pulmonary involvement and those of patients without pulmonary involvement were observed. Tentative criteria for initiation and effect of therapy were proposed. In conclusion, the chronic visceral subtype of ASMD showed a predominantly stable disease course in this cohort. We propose that ERT should be initiated on an individual basis and only in case of progression or symptomatic disease. Collection and analysis of real world data are necessary to refine start, stop and follow-up criteria in the future.

Endogenous C-type natriuretic peptide offsets the pathogenesis of steatohepatitis, hepatic fibrosis, and portal hypertension

Metabolic dysfunction-associated steatotic liver disease (MASLD), hepatic fibrosis, and portal hypertension constitute an increasing public health problem due to the growing prevalence of obesity and diabetes. C-type natriuretic peptide (CNP) is an endogenous regulator of cardiovascular homeostasis, immune cell reactivity, and fibrotic disease. Thus, we investigated a role for CNP in the pathogenesis of MASLD. Wild-type (WT), global CNP (gbCNP-/-), and natriuretic peptide receptor-C (NPR-C-/-) knockout mice were fed a choline-deficient defined amino acid diet or administered CCl4. Liver damage was assessed by histological and biochemical analyses, with steatosis and portal vein size determined by ultrasound. Portal vein pressure and reactivity were measured in vivo and ex vivo, respectively. Pharmacological CNP delivery was used to evaluate prospective therapeutic benefit, and plasma CNP concentration was compared in controls and patients with cirrhosis. Circulating CNP concentration was lower in patients with cirrhosis compared with controls. gbCNP-/- mice were more susceptible, versus WT, to advanced steatohepatitis and hepatic fibrosis, characterized by increased immune cell infiltration, fibrosis, ballooning, plasma alanine aminotransferase concentration, and up-regulation of markers driving these processes. gbCNP-/- mice had increased portal vein diameter and pressure, underpinned by CNP insensitivity. NPR-C-/- animals recapitulated, comparatively, the exaggerated pathogenic phenotype in gbCNP-/- mice, whereas CNP reduced hepatic stellate cell proliferation via NPR-B-dependent inhibition of extracellular signal-related kinase 1/2. Administration of CNP reversed many aspects of disease severity. These data define a new intrinsic role for CNP in offsetting the pathogenesis of MASLD, hepatic fibrosis, and portal hypertension and the potential for targeting CNP signaling for treating these disorders.

Roles of X-box binding protein 1 in liver pathogenesis

The prevalence of drug-induced liver injury (DILI) and viral liver infections presents significant challenges in modern healthcare and contributes to considerable morbidity and mortality worldwide. Concurrently, metabolic dysfunctionassociated steatotic liver disease (MASLD) has emerged as a major public health concern, reflecting the increasing rates of obesity and leading to more severe complications such as fibrosis and hepatocellular carcinoma. X-box binding protein 1 (XBP1) is a distinct transcription factor with a basic-region leucine zipper structure, whose activity is regulated by alternative splicing in response to disruptions in endoplasmic reticulum (ER) homeostasis and the unfolded protein response (UPR) activation. XBP1 interacts with a key signaling component of the highly conserved UPR and is critical in determining cell fate when responding to ER stress in liver diseases. This review aims to elucidate the emerging roles and molecular mechanisms of XBP1 in liver pathogenesis, focusing on its involvement in DILI, viral liver infections, MASLD, fibrosis/cirrhosis, and liver cancer. Understanding the multifaceted functions of XBP1 in these liver diseases offers insights into potential therapeutic strategies to restore ER homeostasis and mitigate liver damage.

Advanced Liver Fibrosis Predicts Liver Outcomes in Biopsy-proven Metabolic Dysfunction-associated Steatotic Liver Disease: A U.S.-based Single-center Retrospective Cohort Study

Background and Aims

Data regarding risk factors and long-term outcomes of U.S. patients with biopsy-proven metabolic dysfunction-associated steatotic liver disease (MASLD) are limited. This study aimed to investigate the role of clinical and histologic risk factors on long-term outcomes in patients with MASLD.

Methods

A retrospective cohort study of 451 adults with biopsy-proven MASLD was conducted at a U.S. academic hospital from 2012 to 2020. An experienced pathologist evaluated the index liver biopsy. Patients with a prior liver transplant or alternative etiologies of chronic liver disease were excluded. The duration of the risk exposure was determined from the date of the index liver biopsy to an outcome event or the last follow-up examination. Outcome events of interest included incident liver-related events, liver decompensation, and all-cause mortality.

Results

In the final cohort of 406 patients followed for a median of 3.7 years (interquartile range: 4.8 years), 35 patients died, 41 developed hepatic decompensation, and 70 experienced a liver-related event. Among histologic risk factors, stage 3 (adjusted Hazard ratio (aHR) 2.68, 95% confidence interval (CI) 1.18-6.11) and stage 4 (aHR 6.96, 95% CI 3.55-13.64) fibrosis were associated with incident liver-related events compared to stage 0-1 fibrosis. Stage 4 (aHR 8.46, 95% CI 3.26-21.99) fibrosis alone was associated with incident liver decompensation events compared to stage 0-1 fibrosis. Among clinical risk factors, hypertension (aHR 2.58, 95% CI 1.05-6.34) was associated with incident liver decompensation.

Conclusions

In a U.S. single-center cohort of patients with biopsy-proven MASLD, advanced fibrosis was the primary risk factor for incident liver decompensation and liver-related events.

Characterization of the hepatic flora and metabolome in nonalcoholic fatty liver disease

Background/aim

The purpose of this study was to examine the hepatic bacterial composition and metabolome characteristics of patients with NAFLD using 16S rDNA sequencing and metabolomics. The results of the study revealed substantial differences in hepatic bacterial composition and metabolites between the NAFLD group and the control group. These differences were used to identify potential biomarkers that could be employed to diagnose NAFLD.

Subjects/methods

Liver tissues from 13 patients in the NAFLD group and 12 patients in the control group were collected for microbiota examination.

Results

The bacterial DNA profiles of the liver were significantly different between NAFLD patients and controls. NAFLD patients exhibited an enrichment of Enterobacterales, Mycobacteriales, Pseudomonadales, Flavobacteriales and Xanthomonadales, Sphingomonadales, Lysobact, which was characterised by a lack of erales. At the genus level, the abundance values of Escherichia-Shigella, Rhodococcus, and Chryseobacterium in the NAFLD group were significantly elevated, while the abundance values of Stenotrophomonas, Lawsonella and Sphingobium were significantly reduced. A total of 402 distinct metabolites were identified between the two groups, with 78 metabolites that were up-regulated and 14 metabolites that were down-regulated. The enrichment of metabolic pathways indicated that linoleic acid metabolism was the most significant contributor to the metabolic differences, and lipid metabolism was substantially differentiated. The hepatic metabolite levels were substantially correlated with the changes in hepatic microflora, as demonstrated by the correlation analysis.

Conclusion

Differences in pathogenesis and host physiological function of NAFLD may be attributed to the hepatic flora and metabolomic characteristics. In the future, this presents new opportunities for the investigation of prospective diagnostic and therapeutic targets for NAFLD.

Risk of Adverse Events in Anticoagulated Patients With Atrial Fibrillation and Nonalcoholic Fatty Liver Disease

BACKGROUND

The clinical impact of nonalcoholic fatty liver disease (NAFLD) in patients with atrial fibrillation (AF) is still controversial.

AIM

To evaluate the 1-year risk of all-cause death, thromboembolic events, and bleeding in patients with AF-NAFLD.

METHODS

Retrospective study with a health research network (TriNetX). Patients with AF on oral anticoagulation (OAC) were categorized according to the presence of NAFLD into 2 groups. The primary outcomes were the 1-year risks of (1) a composite cardiovascular outcome (all-cause death, myocardial infarction, stroke, cardiac arrest, and pulmonary embolism) and (2) a composite hemorrhagic outcome (intracranial hemorrhage and gastrointestinal bleeding). Cox regression analysis before and after propensity score matching was used to estimate hazard ratio (HR) and 95% 95% CI,. Sensitivity analyses investigated the risk associated with cirrhosis, thrombocytopenia, and type of OAC (warfarin vs non-vitamin K antagonist oral anticoagulants (NOACs).

RESULTS

We identified 22 636 patients with AF-NAFLD (69 ± 12 years, 46.7% females) and 391 014 patients with AF and without liver disease (72 ± 12 years, 42.7% females). NAFLD was associated with a higher risk of composite cardiovascular (HR, 1.54; 95% CI, 1.47-1.61) and hemorrhagic (HR, 1.56; 95% CI, 1.42-1.72) outcomes. This was consistent also for all the single outcomes. Cirrhotic and thrombocytopenic patients with AF-NAFLD showed the highest risks. Compared to patients with AF-NAFLD on NOACs, those on warfarin were associated with a higher risk of cardiovascular and hemorrhagic outcomes.

CONCLUSION

In patients with AF, NAFLD is associated with a higher 1-year risk of adverse events, with the risk of adverse events progressively increasing from noncirrhotic to cirrhotic and from nonthrombocytopenic to thrombocytopenic patients. NOACs were associated with a better effectiveness and safety profile compared to warfarin.

6-Gingerol, a Bioactive Compound of Zingiber officinale, Ameliorates High-Fat High-Fructose Diet-Induced Non-Alcoholic Related Fatty Liver Disease in Rats

Purpose

Endoplasmic reticulum (ER) stress has a prominent role in the pathogenesis of high-fat diet-induced non-alcohol related fatty liver disease (NAFLD). The aim of this study is to investigate the effects of 6-G on the reduction of ER stress-induced NAFLD in metabolic syndrome (MetS) rats.

Methods

Twenty-five male Sprague-Dawley rats were fed with a high-fat high-fructose (HFHF) diet for 16 weeks. The rats were treated orally with 6-G (50,100, and 200 mg/kgBW) once daily for eight weeks. At Week 16, all animals were sacrificed, and serum and liver tissue were harvested for biochemical and structural analysis.

Results

NAFLD liver rats were shown to have elevated protein expression of GRP78, and ER-associated apoptotic protein, such as IRE1, TRAF2, p-JNK, and p-NF-κB, which were considerably reduced by the 6-G at three doses treatment. Furthermore, a significant increase in liver apoptosis and non-alcoholic steatohepatitis (NAS) score were observed in the NAFLD rat liver and which were also attenuated by the 6-G treatment at three doses. 6-G treatment also reduced ALT, AST, and ALP serum levels.

Conclusion

Considering all the findings, it is suggested that the 6-G treatment could be a potential candidate therapy in treating ER stress-induced NAFLD in rats.

The Hyperdense Right Hemidiaphragm Sign: A Novel Radiological Indicator of Diffuse Fatty Liver Infiltration on Non-Enhanced CT

Objectives The primary objective of this study is to describe and evaluate the diagnostic performance of the hyperdense right hemidiaphragm sign (HRHS) as a novel radiological indicator for diffuse fatty infiltration of the liver on non-enhanced CT (NECT) scans. This includes assessing its sensitivity, specificity, positive predictive value, and negative predictive value, and comparing these metrics with other established NECT signs. Methods This cross-sectional multicenter retrospective study included all patients over 12 years of age who underwent both abdominal MRI and NECT scans of the abdomen within a period not exceeding six months at two tertiary hospitals (The Royal Hospital and Armed Forces Hospital, Muscat, Sultanate of Oman) between January 2010 and December 2022. Two readers reviewed the NECT scan images for the following signs: HRHS, liver density of less than 10 HU compared to the spleen, absolute liver density of <40 HU, and hyperattenuated intrahepatic vessels. The drop in signal on the out-phase sequence compared to the in-phase sequence on MRI was used as the gold standard reference for diagnosing diffuse fatty infiltration of the liver. Data were analyzed using IBM SPSS Statistics for Windows, Version 26.0 (Released 2019; IBM Corp., Armonk, NY, USA) and MedCalc software (MedCalc Software Ltd., Oostende, Belgium), with sensitivity, specificity, and positive and negative predictive values calculated for each NECT sign. Results A total of 340 patients were included in this study, with a mean age of 54 years. Among these patients, 45 were diagnosed with diffuse fatty infiltration of the liver by MRI. Thirty-six patients were identified as positive for fatty liver infiltration on unenhanced CT based on the criterion of the HRHS, with a sensitivity of 91%, specificity of 99%, positive predictive value of 94%, and negative predictive value of 99%. In contrast, 45 patients were positive using the criterion of liver density less than 10 HU compared to the spleen, yielding a sensitivity of 83%, a specificity of 98%, a positive predictive value of 88%, and a negative predictive value of 97%. Using the criterion of absolute liver density <40 HU, 30 patients were positive, with a sensitivity of 72%, specificity of 98%, positive predictive value of 90%, and negative predictive value of 96%. Lastly, 20 patients were positive using the criterion of hyperattenuated intrahepatic vessels, with a sensitivity of 51%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 93%. Conclusions The proposed qualitative evaluation using the HRHS for diffuse fatty infiltration of the liver on NECT scans demonstrates the highest sensitivity compared to other previously described NECT signs.

Low circulating levels of neuregulin 4 as a potential biomarker associated with the severity and prognosis of obesity-related metabolic diseases: a systematic review

BACKGROUND

Neuregulin 4 (Nrg4) is a brown adipose tissue-derived adipokine that greatly affects systemic metabolism and improves metabolic derangements. Although abnormal circulating levels of Nrg4 are common in obesity, it remains elusive whether low or elevated levels of this batokine are associated with the onset of metabolic diseases.

AIM

To assess Nrg4 levels and its role as a feasible biomarker to predict the severity of obesity, gestational diabetes mellitus (GDM), type 2 diabetes mellitus (T2DM), non-alcoholic fatty liver disease (NAFLD), and cardiovascular diseases (CVD).

METHODS

A search for relevant studies was performed systematically using prominent search engines, including PubMed, Google Scholar, and Embase, by following PRISMA guidelines.

RESULTS

Ample clinical evidence reported low serum/plasma levels of Nrg4 in obesity and these were inversely proportional to the indices of metabolic syndrome, including body mass index, waist circumference, triglycerides, fasting plasma glucose, and homoeostatic model assessment for insulin resistance as well as high-sensitivity C-reactive protein. Low circulating Nrg4 levels may aid in the prediction of morbid obesity, and subsequent GDM, T2DM, NAFLD, and CVD.

CONCLUSION

Current clinical evidence emphasizes that the circulating levels of Nrg4 are decreased in morbid obesity, and it also highlights that Nrg4 May serve as a potential prognostic biomarker for obesity-related metabolic diseases.

Forns index and fatty liver index, but not FIB-4, are associated with indices of glycaemia, pre-diabetes and type 2 diabetes: analysis of The Maastricht Study

OBJECTIVE

Glucose metabolism status (GMS) is linked to non-alcoholic fatty liver disease (NAFLD). Higher levels of advanced glycation end products (AGEs) are observed in people with type 2 diabetes mellitus (T2DM) and NAFLD. We examined the association between GMS, non-invasive tests and AGEs, with liver steatosis and fibrosis.

METHODS

Data from The Maastricht Study, a population-based cohort, were analysed. Participants with alcohol overconsumption or missing data were excluded. GMS was determined via an oral glucose tolerance test. AGEs, measured by skin autofluorescence (SAF), were assessed using an AGE Reader. Associations of GMS and SAF with the fibrosis-4 score (FIB-4), Forns index (FI) and fatty liver index (FLI) were investigated using multivariable linear regression, adjusted for sociodemographic, lifestyle and clinical variables.

RESULTS

1955 participants (56.6%) were analysed: 598 (30.6%) had T2DM, 264 (13.5%) had pre-diabetes and 1069 (54.7%) had normal glucose metabolism. Pre-diabetes was significantly associated with FLI (standardised regression coefficient (Stβ) 0.396, 95% CI 0.323 to 0.471) and FI (Stβ 0.145, 95% CI 0.059 to 0.232) but not FIB-4. T2DM was significantly associated with FLI (Stβ 0.623, 95% CI 0.552 to 0.694) and FI (Stβ 0.307, 95% CI 0.226 to 0.388) but not FIB-4. SAF was significantly associated with FLI (Stβ 0.083, 95% CI 0.036 to 0.129), FI (Stβ 0.106, 95% CI 0.069 to 0.143) and FIB-4 (Stβ 0.087, 95% CI 0.037 to 0.137).

CONCLUSION

The study showed that adverse GMS and higher glycaemia are positively associated with steatosis. FI, but not FIB-4, was related to adverse GMS concerning fibrosis. This study is the first to demonstrate that SAF is positively associated with steatosis and fibrosis.

ASPP2 deficiency promotes the progression of metabolic dysfunction-associated steatohepatitis via ACSL4 upregulation

As a member of the p53-binding protein family, apoptosis-stimulating protein p53 2 (ASPP2) is closely related to autophagy and apoptosis. However, the mechanistic role of ASPP2 in the development of metabolic dysfunction-associated steatohepatitis (MASH) remains elusive. Therefore, we investigated the role and underlying mechanisms of ASPP2 in MASH progression in a mouse model of MASH and a cellular model of metabolic dysfunction-associated fatty liver disease. ASPP2 deficiency significantly promoted the inflammatory response, steatosis, and MASH progression in mice. Through transcriptomic analysis, increased ACSL4 expression was identified as a potential key factor. Further elucidation of the underlying mechanisms demonstrated that ASPP2 deficiency increased lipid accumulation and inhibited mitochondrial respiration capacity in HepG2 cells induced by oleic acid. However, silencing of ACSL4 reversed these effects. Thus, our study indicates that ASPP2 is an important regulator of MASH progression through ACSL4 upregulation, highlighting its potential as an alternative approach to MASH treatment.

An antifibrotic compound that ameliorates hyperglycaemia and fat accumulation in cell and HFD mouse models

AIMS/HYPOTHESIS

Appropriate management of blood glucose levels and the prevention of complications are important in the treatment of diabetes. We have previously reported on a compound named HPH-15 that is not only antifibrotic but also AMP-activated protein kinase (AMPK)-activating. In this study, we evaluated whether HPH-15 is useful as a therapeutic medication for diabetes.

METHODS

We examined the effects of HPH-15 on AMPK activation, glucose uptake, fat accumulation and lactic acid production in L6-GLUT4, HepG2 and 3T3-L1 cells, as a model of muscle, liver and fat tissue, respectively. Additionally, we investigated the glucose-lowering, fat-accumulation-suppressing, antifibrotic and AMPK-activating effect of HPH-15 in mice fed a high-fat diet (HFD).

RESULTS

HPH-15 at a concentration of 10 µmol/l increased AMPK activation, glucose uptake and membrane translocation of GLUT4 in each cell model to the same extent as metformin at 2 mmol/l. The production of lactic acid (which causes lactic acidosis) in HPH-15-treated cells was equal to or less than that observed in metformin-treated cells. In HFD-fed mice, HPH-15 lowered blood glucose from 11.1±0.3 mmol/l to 8.2±0.4 mmol/l (10 mg/kg) and 7.9±0.4 mmol/l (100 mg/kg) and improved insulin resistance. The HPH-15 (10 mg/kg) group showed the same level of AMPK activation as the metformin (300 mg/kg) group in all organs. The HPH-15-treated HFD-fed mice also showed suppression of fat accumulation and fibrosis in the liver and fat tissue; these effects were more significant than those obtained with metformin. Mice treated with high doses of HPH-15 also exhibited a 44% reduction in subcutaneous fat.

CONCLUSIONS/INTERPRETATION

HPH-15 activated AMPK at lower concentrations than metformin in vitro and in vivo and improved blood glucose levels and insulin resistance in vivo. In addition, HPH-15 was more effective than metformin at ameliorating fatty liver and adipocyte hypertrophy in HFD-fed mice. HPH-15 could be effective in preventing fatty liver, a common complication in diabetic individuals. Additionally, in contrast to metformin, high doses of HPH-15 reduced subcutaneous fat in HFD-fed mice. Presumably, HPH-15 has a stronger inhibitory effect on fat accumulation and fibrosis than metformin, accounting for the reduction of subcutaneous fat. Therefore, HPH-15 is potentially a glucose-lowering medication that can lower blood glucose, inhibit fat accumulation and ameliorate liver fibrosis.

Macrophages and T cells in metabolic disorder-associated cancers

Cancer and metabolic disorders have emerged as major global health challenges, reaching epidemic levels in recent decades. Often viewed as separate issues, metabolic disorders are shown by mounting evidence to heighten cancer risk and incidence. The intricacies underlying this connection are still being unraveled and encompass a complex interplay between metabolites, cancer cells and immune cells within the tumour microenvironment (TME). Here, we outline the interplay between metabolic and immune cell dysfunction in the context of three highly prevalent metabolic disorders, namely obesity; two associated liver diseases, metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH); and type 2 diabetes. We focus primarily on macrophages and T cells, the critical roles of which in dictating inflammatory response and immune surveillance in metabolic disorder-associated cancers are widely reported. Moreover, considering the ever-increasing number of patients prescribed with metabolism disorder-altering drugs and diets in recent years, we discuss how these therapies modulate systemic and local immune phenotypes, consequently impacting cancer malignancy. Collectively, unraveling the determinants of metabolic disorder-associated immune landscape and their role in fuelling cancer malignancy will provide a framework essential to therapeutically address these highly prevalent diseases.

Pea Albumin Alleviates Oleic Acid-Induced Lipid Accumulation in LO2 Cells Through Modulating Lipid Metabolism and Fatty Acid Oxidation Pathways

Excessive lipid accumulation in the liver can cause NAFLD, leading to chronic liver injury. To relieve liver lipid accumulation by dietary proteins, this study used oleic acid (OA) induction to establish a stable in vitro LO2 cell lipid accumulation model. This model was used to explore the mechanism by which pea albumin (PA) regulates lipid levels in LO2 cells. PA has been shown to ameliorate OA-induced lipid accumulation in LO2 cells by reducing the aggregation of intracellular lipid droplets and lowering cell TG and TC levels. In addition, it can alleviate OA-induced LO2 cell damage and oxidative stress, reduce cellular ALT and AST secretion, lower cellular MDA levels, and increase GSH-Px viability. Regulation of lipid metabolism in LO2 cells involves inhibiting the cellular lipid synthesis pathway and activating the expression of proteins related to the triglyceride catabolic and fatty acid oxidation pathways. PA contributes to regulating lipid accumulation in LO2 cells. This study provides new insights into alleviating liver fat accumulation and a theoretical basis for exploring the mechanism of protein regulation of liver cell lipid metabolism.

U-shaped association of serum vitamin A concentrations with all-cause mortality in patients with NAFLD: results from the NHANES database prospective cohort study

Background

Previous studies have demonstrated a significant association between serum vitamin A concentration and non-alcoholic fatty liver disease (NAFLD) development. However, the long-term prognostic implications of serum vitamin A in patients with NAFLD remain underexplored. This study aims to investigate whether there exists a correlation between serum vitamin A concentrations and overall mortality among subjects diagnosed with NAFLD.

Methods

To investigate the association between serum vitamin A concentrations and NAFLD outcomes, we conducted prospective cohort studies using data from the 1999-2006 and 2017-2018 National Health and Nutrition Examination Survey (NHANES). We utilized a multivariate Cox regression model to explore the relationship between serum vitamin A levels and all-cause mortality. Survival curves related to serum vitamin A were constructed using the Kaplan-Meier method. Additionally, the restricted cubic splines (RCS) method was applied to examine potential nonlinear relationships between serum vitamin A concentrations and all-cause mortality of NAFLD.

Results

Over a median follow-up period of 10.3 years, a total of 1,399 all-cause deaths were recorded. The weighted average concentration of serum vitamin A was 61.48 ± 0.37 μg/dL. After adjusting for potential confounders, a significant U-shaped relationship was identified between serum vitamin A concentrations and the risk of all-cause mortality in NAFLD patients. This relationship was particularly pronounced in men and elderly individuals aged 60 to 85.

Conclusion

Our study reveals a significant non-linear relationship between serum vitamin A concentrations and the risk of all-cause mortality in patients with NAFLD. These findings underscore the importance of monitoring and maintaining optimal serum vitamin A levels to potentially improve survival outcomes in NAFLD patients.

Knock-Out of IKKepsilon Ameliorates Atherosclerosis and Fatty Liver Disease by Alterations of Lipid Metabolism in the PCSK9 Model in Mice

The inhibitor-kappaB kinase epsilon (IKKε) represents a non-canonical IκB kinase that modulates NF-κB activity and interferon I responses. Inhibition of this pathway has been linked with atherosclerosis and metabolic dysfunction-associated steatotic liver disease (MASLD), yet the results are contradictory. In this study, we employed a combined model of hepatic PCSK9D377Y overexpression and a high-fat diet for 16 weeks to induce atherosclerosis and liver steatosis. The development of atherosclerotic plaques, serum lipid concentrations, and lipid metabolism in the liver and adipose tissue were compared between wild-type and IKKε knock-out mice. The formation and progression of plaques were markedly reduced in IKKε knockout mice, accompanied by reduced serum cholesterol levels, fat deposition, and macrophage infiltration within the plaque. Additionally, the development of a fatty liver was diminished in these mice, which may be attributed to decreased levels of multiple lipid species, particularly monounsaturated fatty acids, triglycerides, and ceramides in the serum. The modulation of several proteins within the liver and adipose tissue suggests that de novo lipogenesis and the inflammatory response are suppressed as a consequence of IKKε inhibition. In conclusion, our data suggest that the knockout of IKKε is involved in mechanisms of both atherosclerosis and MASLD. Inhibition of this pathway may therefore represent a novel approach to the treatment of cardiovascular and metabolic diseases.

Trimethylamine N-oxide induces non-alcoholic fatty liver disease by activating the PERK

Nonalcoholic fatty liver disease (NAFLD) is a liver disease causing different progressive pathological changes. Trimethylamine N-oxide (TMAO), a product of gut microbiota metabolism, is a specific agonist of the protein kinase R-like endoplasmic reticulum kinase (PERK) pathway, one of the endoplasmic reticulum stress (ERS) pathways. TMAO has been associated with the occurrence and development of NAFLD based on the results of previous studies, but whether the simple consumption of TMAO can directly induce NAFLD and its underlying mechanism remain unclear. To investigate this question, we constructed an animal model in which adult male zebrafish were fed a controlled diet containing 1 % or 3 % TMAO for 20 weeks. Eventually, we observed that TMAO caused lipid accumulation, inflammatory infiltration, liver injury and liver fibrosis in zebrafish livers; meanwhile, the PERK signaling pathway was activated in the zebrafish livers. This finding was further confirmed in HepG2 cells and hepatic stellate cells models. In conclusion, this study found that TMAO directly induced different pathological states of NAFLD in zebrafish liver, and the activation of PERK pathway is an important mechanism, which may provide crucial strategies for the diagnosis and treatment of NAFLD.

The development of hepatic steatosis depends on the presence of liver-innervating parasympathetic cholinergic neurons in mice fed a high-fat diet

Hepatic lipid metabolism is regulated by the autonomic nervous system of the liver, with the sympathetic innervation being extensively studied, while the parasympathetic efferent innervation is less understood despite its potential importance. In this study, we investigate the consequences of disrupted brain-liver communication on hepatic lipid metabolism in mice exposed to obesogenic conditions. We found that a subset of hepatocytes and cholangiocytes are innervated by parasympathetic nerve terminals originating from the dorsal motor nucleus of the vagus. The elimination of the brain-liver axis by deleting parasympathetic cholinergic neurons innervating the liver prevents hepatic steatosis and promotes browning of inguinal white adipose tissue (ingWAT). The loss of liver-innervating cholinergic neurons increases hepatic Cyp7b1 expression and fasting serum bile acid levels. Furthermore, knockdown of the G protein-coupled bile acid receptor 1 gene in ingWAT reverses the beneficial effects of the loss of liver-innervating cholinergic neurons, leading to the reappearance of hepatic steatosis. Deleting liver-innervating cholinergic neurons has a small but significant effect on body weight, which is accompanied by an increase in energy expenditure. Taken together, these data suggest that targeting the parasympathetic cholinergic innervation of the liver is a potential therapeutic approach for enhancing hepatic lipid metabolism in obesity and diabetes.

Toxic Beauty: Parabens and benzophenone-type UV Filters linked to increased non-alcoholic fatty liver disease risk

The prevalence of non-alcoholic fatty liver disease (NAFLD) has increased concomitantly with heightened exposure to environmental chemicals, such as benzophenone-type ultraviolet (BP-type UV) filters and parabens, which are prevalent in personal care products. This study aimed to investigate the potential link between the exposure to these chemicals and the risk of developing NAFLD. We conducted a case-control study involving 228 participants from South China, encompassing individuals diagnosed with NAFLD and healthy controls. Blood samples were collected and analyzed for the presence of 11 parabens and 8 BP-type UV filters. The findings revealed significantly elevated concentrations of several parabens and BP-type UV filters in the blood of patients with NAFLD compared with the healthy cohort. Notably, methylparaben (MeP), ethylparaben (EtP), isopropylparaben (iPrP), butylparaben (BuP), isobutylparaben (iBuP), 3,4-dihydroxybenzoic acid (3,4-DHB), total parabens (Σparabens), BP1, BP3, BP4, and 4-hydroxybenzophenone (4-OH-BP) were identified as significant predictors of NAFLD prevalence. Through multiple regression analyses, the blood levels of iBuP, Σparabens, and BP4 were found to be significantly associated with elevated triglycerides (TG) (β = 0.59 mmol/L, 95% CI = 0.11-1.59), total bilirubin (TBIL) (β = 2.81 μmol/L, 95% CI = 0.46-15.6) or direct bilirubin (DBIL) (β = 1.89 μmol/L, 95% CI = 0.47-10.2), and reduced globulins (GLB) (β = -0.29 g/L, 95% CI = -0.07 to -5.45), respectively, which are indicators of liver damage. Moreover, TBIL and DBIL were found to mediate 26.7% and 24.6% of the increase in NAFLD prevalence associated with Σparabens, respectively. In conclusion, this study offers pioneering insights into human exposure to parabens and BP-type UV filters as well as their hepatotoxic potential.

Tissue-specific activation of insulin signaling as a potential target for obesity-related metabolic disorders

The incidence of obesity is rapidly increasing worldwide. Obesity-associated insulin resistance has long been established as a significant risk factor for obesity-related disorders such as type 2 diabetes and atherosclerosis. Insulin plays a key role in systemic glucose metabolism, with the liver, skeletal muscle, and adipose tissue as the major acting tissues. Insulin receptors and the downstream insulin signaling-related molecules are expressed in various tissues, including vascular endothelial cells, vascular smooth muscle cells, and monocytes/macrophages. In obesity, decreased insulin action is considered a driver for associated disorders. However, whether insulin action has a positive or negative effect on obesity-related disorders depends on the tissue in which it acts. While an enhancement of insulin signaling in the liver increases hepatic fat accumulation and exacerbates dyslipidemia, enhancement of insulin signaling in adipose tissue protects against obesity-related dysfunction of various organs by increasing the capacity for fat accumulation in the adipose tissue and inhibiting ectopic fat accumulation. Thus, this "healthy adipose tissue expansion" by enhancing insulin sensitivity in adipose tissue, but not in the liver, may be an effective therapeutic strategy for obesity-related disorders. To effectively address obesity-related metabolic disorders, the mechanisms of insulin resistance in various tissues of obese patients must be understood and drugs that enhance insulin action must be developed. In this article, we review the potential of interventions that enhance insulin signaling as a therapeutic strategy for obesity-related disorders, focusing on the molecular mechanisms of insulin action in each tissue.

The development of hepatic steatosis depends on the presence of liver-innervating parasympathetic cholinergic neurons in mice fed a high-fat diet

Hepatic lipid metabolism is regulated by the autonomic nervous system of the liver, with the sympathetic innervation being extensively studied, while the parasympathetic efferent innervation is less understood despite its potential importance. In this study, we investigate the consequences of disrupted brain-liver communication on hepatic lipid metabolism in mice exposed to obesogenic conditions. We found that a subset of hepatocytes and cholangiocytes are innervated by parasympathetic nerve terminals originating from the dorsal motor nucleus of the vagus. The elimination of the brain-liver axis by deleting parasympathetic cholinergic neurons innervating the liver prevents hepatic steatosis and promotes browning of inguinal white adipose tissue (ingWAT). The loss of liver-innervating cholinergic neurons increases hepatic Cyp7b1 expression and fasting serum bile acid levels. Furthermore, knockdown of the G protein-coupled bile acid receptor 1 gene in ingWAT reverses the beneficial effects of the loss of liver-innervating cholinergic neurons, leading to the reappearance of hepatic steatosis. Deleting liver-innervating cholinergic neurons has a small but significant effect on body weight, which is accompanied by an increase in energy expenditure. Taken together, these data suggest that targeting the parasympathetic cholinergic innervation of the liver is a potential therapeutic approach for enhancing hepatic lipid metabolism in obesity and diabetes.

When the liver is in poor condition, so is the heart - cardiac remodelling in MASH mouse models

Metabolic dysfunction-associated steatohepatitis (MASH) confers a risk for cardiovascular diseases in patients. Animal models may help exploring the mechanisms linking liver and heart diseases. Hence, we explored the cardiac phenotype in two MASH mouse models: foz/foz mice fed a high-fat diet (HFD) for 24 or 60 weeks and C57BL/6J mice fed a high-fat-, high-cholesterol-, and high-fructose diet for 60 weeks. Angiotensin II (AngII) was used as an additional cardiovascular stressor for 4 weeks in 10 weeks HFD-fed foz/foz mice. Foz/foz mice with fibrosing MASH developed cardiac hypertrophy with adverse cardiac remodelling not seen in WT similarly fed the HFD. AngII caused hypertension and up-regulated the expression of genes contributing to pathological cardiac hypertrophy (Nppa, Myh7) more severely so in foz/foz mice than in controls. After 60 weeks of HFD, while liver disease had progressed to burn-out non steatotic MASH with hepatocellular carcinoma in 50% of the animals, the cardiomyopathy did not. In an independent model (C57BL/6J mice fed a fat-, cholesterol- and fructose-rich diet), moderate fibrosing MASH is associated with cardiac fibrosis and dysregulation of genes involved in pathological remodelling (Col1a1, Col3a1, Vim, Myh6, Slc2a1). Thus, animals with MASH present consistent adverse structural changes in the heart with no patent alteration of cardiac function even when stressed with exogenous AngII. Liver disease, and likely not overfeeding or aging alone, is associated with this cardiac phenotype. Our findings support foz/foz mice as suitable for studying links between MASH and heart structural changes ahead of heart failure.

Strong associations between fasting lipids and glucose concentrations and ALT levels strengthened with increasing ALT quantiles

BACKGROUND

A persistent redox state and excessive reactive species involved in carbohydrate and lipid metabolism lead to oxidative damage in the liver, however, how fasting plasma concentrations of lipids and glucose are associated with fasting blood levels of alanine transaminase (ALT) and aspartate transaminase (AST) remains to be evaluated in large-scale population.

METHODS

A cross-sectional study with 182,971 residents aged 18 to 92 years; multidimensional stratified analyses including quantile linear regression analysis and sex stratification were adopted to improve the quality of the evidence.

RESULTS

The associations between the concentrations of non-HDL-C and triglyceride and ALT levels were positive, stronger in males in each quantile of ALT levels and the coefficients expanded with increasing ALT levels at slopes of 3.610 and 5.678 in males and 2.977 and 5.165 in females, respectively. The associations between the HDL-C concentrations and ALT levels were negative, also stronger in males in each quantile and the coefficients expanded with increasing ALT levels at slopes of -7.839 in females and - 5.797 in males. The associations between glucose concentrations and ALT levels were positive, but stronger in females in each quantile and the coefficients expanded with increasing ALT levels at slopes of 1.736 in males and 2.177 in females, respectively. Similar pattern consist of relatively weaker coefficients and slops were observed between concentrations of non-HDL-C, triglyceride and glucose and AST levels. The associations between albumin concentration and concentrations of blood lipids and glucose were relatively steady across all quantiles.

CONCLUSIONS

The dose dependent effect between blood concentrations of lipids and glucose and liver function changes suggests that excessive carbohydrate and lipid metabolism may cause subclinical liver damage. Long term sustained primary and secondary inflammatory factors produced in the liver might be transmitted to adjacent organs, such as the heart, kidneys, and lungs, to cause and/or exacerbate pathological changes in these visceral organs.

Soft drink consumption and increased risk of nonalcoholic fatty liver disease: Results from the health workers cohort study

INTRODUCTION AND OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) is a common clinical condition and an important public health problem. Some epidemiological studies have suggested that soft drinks (SD) intake is associated with NAFLD. However, the evidence is inconsistent. Our objective was to assess the association between SD consumption and the risk of NAFLD in a Mexican adult population.

MATERIALS AND METHODS

A total of 1,759 participants from the Health Workers Cohort Study (HWCS) were included in the analyses. SD intake was measured using a validated food frequency questionnaire. We classified SD consumption as follows: a) less than 1 serving per week, b) 1 to less than 3.5 servings per week, and c) 3.5 or more servings per week. Hepatic steatosis index (HSI) was calculated based on sex, BMI, and blood transaminase levels, and was categorized as NAFLD ≥ 36. To assess the relation between SD and NAFLD, we followed two approaches: fixed effects logistic regression and generalized estimating equations.

RESULTS

After adjusting for demographic characteristics, lifestyle factors, and dietary intake, the odds ratio (OR) and 95 % confidence interval (95 % CI) for NAFLD were 1.26 (95 % CI: 1.08, 1.48) for 1 to less than 3.5 servings per week and 1.42 (95 % CI: 1.19, 1.69) for ≥3.5 servings/week category in both sexes. When stratifying the analysis by sex, we observed that the association tended to be greater in men than in women.

CONCLUSIONS

The results from our prospective study indicate that SD consumption is associated with an increased risk of NAFLD.

Risk Factors for Non-Alcoholic Fatty Liver Disease in Patients with Bipolar Disorder: A Cross-Sectional Retrospective Study

Purpose

The co-morbidity of non-alcoholic fatty liver disease (NAFLD) in patients with bipolar disorder (BD) has a negative impact on patient treatment and prognosis. This study aimed to identify the prevalence of NAFLD in patients with BD and investigate the risk factors of NAFLD.

Patients and Methods

A total of 678 patients with BD were included in the study. Clinical data were obtained from the hospital's electronic health record system. Data included fasting blood glucose, alanine aminotransferase, triglycerides, aspartate aminotransferase, high-density lipoprotein cholesterol (HDL), alkaline phosphatase, total cholesterol, glutamine transpeptidase, uric acid, apolipoprotein A1, apolipoprotein B, and liver ultrasound findings.

Results

The prevalence of NAFLD was 43.66% in patients with BD. Significant differences in body mass index (BMI), mean age, diabetes prevalence, course of BD, fasting blood glucose, alanine aminotransferase, HDL, alkaline phosphatase, triglycerides, aspartate aminotransferase, uric acid, glutamine transpeptidase, apolipoprotein B, total cholesterol, and apolipoprotein A1 were seen between the groups (all P<0.01). Male sex, age, BMI, course of BD, alanine aminotransferase, fasting blood glucose, aspartate aminotransferase, diabetes, glutamine transpeptidase, total cholesterol, alkaline phosphatase, triglycerides, uric acid, apolipoprotein B, HDL, and apolipoprotein A1 levels were correlated with NAFLD (all P<0.05). In patients with BD, diabetes (OR=6.412, 95% CI=1.049-39.21), BMI (OR=1.398, 95% CI=1.306-1.497), triglycerides (OR=1.456, 95% CI=1.036-2.045), and apolipoprotein A1 (OR=0.272, 95% CI=0.110-0.672) were risk factors for NAFLD (all P<0.05).

Conclusion

Risk factors for NAFLD in patients with BD include diabetes, BMI, course of BD, and a low level of apolipoprotein A1. A proactive approach to disease management, such as appropriate physical activity and adoption of a healthy diet, and regular monitoring of changes in patient markers should be adopted to reduce the prevalence of NAFLD.

Ginger essential oil prevents NASH progression by blocking the NLRP3 inflammasome and remodeling the gut microbiota-LPS-TLR4 pathway in mice

BACKGROUND

Diet and gut microbiota contribute to non-alcoholic steatohepatitis (NASH) progression. High-fat diets (HFDs) change gut microbiota compositions, induce gut dysbiosis, and intestinal barrier leakage, which facilitates portal influx of pathogen-associated molecular patterns including lipopolysaccharides (LPS) to the liver and triggers inflammation in NASH. Current therapeutic drugs for NASH have adverse side effects; however, several foods and herbs that exhibit hepatoprotection could be an alternative method to prevent NASH.

METHODS

We investigated ginger essential oil (GEO) against palm oil-containing HFDs in LPS-injected murine NASH model.

RESULTS

GEO reduced plasma alanine aminotransferase levels and hepatic pro-inflammatory cytokine levels; and increased antioxidant catalase, glutathione reductase, and glutathione levels to prevent NASH. GEO alleviated hepatic inflammation through mediated NLR family pyrin domain-containing 3 (NLRP3) inflammasome and LPS/Toll-like receptor four (TLR4) signaling pathways. GEO further increased beneficial bacterial abundance and reduced NASH-associated bacterial abundance.

CONCLUSION

This study demonstrated that GEO prevents NASH progression which is probably associated with the alterations of gut microbiota and inhibition of the LPS/TLR4/NF-κB pathway. Hence, GEO may offer a promising application as a dietary supplement for the prevention of NASH.

Physical frailty, genetic predisposition, and the risks of severe non-alcoholic fatty liver disease and cirrhosis: a cohort study

BACKGROUND

Frailty, defined as a phenotype of decreased physiological reserves and diminished ability to respond to stressors, has been linked to the development of chronic diseases. Epidemiological evidence connecting frailty to non-alcoholic fatty liver disease (NAFLD) and cirrhosis risks remain sparse. We aimed to assess the longitudinal associations of frailty with the risks of severe NAFLD and cirrhosis in middle-aged to older adults and further explore the modification role of genetic risk on these associations.

METHODS

This study included a total of 398 386 participants from the UK Biobank. Incident cases of severe NAFLD and cirrhosis were ascertained through linked hospital records and death registries. Frailty status was assessed by a modified version of the frailty phenotype, encompassing five key components: weight loss, tiredness, physical activity, gait speed, and grip strength. Participants were classified as pre-frailty if they met one or two of these criteria, and as frailty if they met three or more. Genetic predisposition to NAFLD and cirrhosis was estimated by genetic risk score (GRS) and further categorized into high, intermediate, and low genetic risk levels according to tertiles of GRSs. Cox proportional hazards regression model was employed to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for their associations.

RESULTS

The mean (standard deviation) age of the study population was 56.6 (8.03) years. 214 408 (53.8%) of the participants was female; 14 924 (3.75%) of participants met the criteria for frailty, 170 498 (42.8%) for pre-frailty, and 212 964 (53.5%) for non-frailty. Over a median follow-up of 12.0 years, we documented 4439 incident severe NAFLD and 3323 incident cirrhosis cases, respectively. Compared with non-frailty, both pre-frailty (HR: 1.50; 95% CI: 1.40-1.60) and frailty (HR: 1.98; 95% CI: 1.77-2.21) were associated with increased risk of NAFLD. Similar associations were observed for cirrhosis, the corresponding HRs (95% CIs) for non-frailty, pre-frailty, and frailty were 1.00 (reference), 1.29 (1.20, 1.38), and 1.90 (1.66, 2.18). Such associations were consistent across all genetic risk levels, with no observed interactions between frailty and GRSs (all P for interactions ≥0.10). Compared with participants with frailty and a low level of genetic risk, the greatest risk increasement in developing severe NAFLD (HR: 3.36; 95% CI: 2.83-3.99) and cirrhosis (HR: 2.81; 95% CI: 2.29-3.44) was both observed in those with frailty and a high level of genetic risk.

CONCLUSIONS

Our findings indicate that frailty is a significant predictor of severe NAFLD and cirrhosis, irrespective of genetic predisposition.

Integrating genetic and socioeconomic data to predict the progression of nonalcoholic fatty liver disease

OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease globally, with an estimated prevalence exceeding 25%. Variants in the PNPLA3 and HSD17B13 genes have been a focus of investigations surrounding the etiology and progression of NAFLD and are believed to contribute to a greater burden of disease experienced by Hispanic Americans. However, little is known about socioeconomic factors influencing NAFLD progression or its increased prevalence among Hispanics.

MATERIALS AND METHODS

We cross-sectionally analyzed 264 patients to assess the role of genetic and socioeconomic variables in the development of advanced liver fibrosis in individuals at risk for NAFLD.

RESULTS

Adjusting for age, sex, body mass index, and PNPLA3 genotype, lacking a college degree was associated with 3.3 times higher odds of advanced fibrosis (95% confidence interval [CI]: 1.21-8.76, p = 0.019), an effect comparable to that of possessing the major PNPLA3 risk variant. Notably, the effect of PNPLA3 genotype on advanced fibrosis was attenuated to nonsignificance following adjustment for education and other socioeconomic markers. The effect of the protective HSD17B13 variant, moreover, diminished after adjustment for education (odds ratio [OR]: 0.39 [95% CI: 0.13-1.16, p = 0.092]), while lower education continued to predict advanced fibrosis following multivariable adjustment with an OR of 8.0 (95% CI: 1.91-33.86, p = 0.005).

DISCUSSION

Adjusting for education attenuated the effects of genotype and Hispanic ethnicity on liver fibrosis, suggesting that social factors-rather than genes or ethnicity-may be driving disease severity within some populations. Findings reveal the importance of including socioenvironmental controls when considering the role of genetics or ethnicity in complex disease.

G-Protein-Coupled Receptor 120 Agonist Mitigates Steatotic and Fibrotic Features Triggered in Obese Mice by the Administration of a High-Fat and High-Carbohydrate Diet

Nonalcoholic fatty liver disease (NALFD) represents a complex condition ranging from simple steatosis (nonalcoholic fatty liver, NAFL) to inflammation, and fibrosis is one of the main features of nonalcoholic steatohepatitis (NASH). The pathogenesis of NAFLD is not well established but involves several factors (i.e., predisposition of genetic variants, obesity, and unhealthy lifestyle as unbalanced diets) that lead to an alteration of lipid homeostasis and consequently to an abnormal accumulation of triglycerides and other lipids in the liver parenchyma. Currently, no resolutive pharmacological treatment for NAFLD is available, and the only therapeutic approach is a healthy diet and physical exercise. In this study, we investigated the potential beneficial effect of GprA, a new synthetic agonist of G-protein-coupled receptor 120/free fatty acid receptor 4 (GPR120/FFAR4), in the progression of NAFL/NASH in mice fed for different periods (26 weeks and 30 weeks), with a high-fat (40% kcal) and high-carbohydrate diet, also called a Western-style diet (WSD). In our experimental model, the histological, protein, and transcriptomic analyses highlighted that the GprA can reduce signs of steatosis in WSD-fed mice. Furthermore, in 30 week-treated mice, GprA is also effective in the reduction of collagen deposition and fibrosis development. Altogether, our data validate the central role of FFAR4 in the context of NAFL/NASH onset and progression and reveal that GprA could represent an interesting candidate for the development of a new therapeutic approach in NAFLD treatment.

ASSOCIATION BETWEEN ANXIETY AND DEPRESSION IN METABOLIC DYSFUNCTION-ASSOCIATED STEATOTIC LIVER DISEASE (MASLD)

BACKGROUND

This study aimed to assess the frequency and intensity of anxious and depressive symptoms in patients diagnosed with metabolic dysfunction-associated steatotic liver disease (MASLD).

METHODS

This is a descriptive and cross-sectional study, resulting from 106 patients from the Hepatology outpatient clinic at the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP), São Paulo, Brazil without a history of alcohol abuse, verified by the alcohol use disorders identification test (AUDIT). These were assessed using the sociodemographic data sheet, Hospital Anxiety and Depression Scale (HADS), Hamilton Anxiety Rating Scale (HAM-A), and Hamilton Depression Scale (HAM-D).

RESULTS

A total of 69.8% were women and 30.2% were men, with a mean age of 61 years. The majority (71.7%) discovered MASLD through routine exams, presenting as comorbidities: Type 2 diabetes mellitus (59.4%), Dyslipidemia (49.1%), Arterial hypertension (68.9%), Obesity (61.3%) and Metabolic syndrome [MetS (63.2%)]. The HADS scale indicates 34% probability of anxiety and 33% depressive symptoms. The Hamilton's scales of intensity indicates 63.9% severe anxiety and 54.3% severe depression. There is also a relationship between anxiety, depression and the female gender, as well as between depression and MetS.

CONCLUSION

The findings point to the presence of anxiety and depression in more than one third of MASLD patients, most with severe symptoms. The group is concentrated in the elderly, with many comorbidities, including MetS. There was a positive correlation between anxiety, depression and being female; also, being significant between MetS and depression.

Pea Albumin Extracted from Pea (Pisum sativum L.) Seeds Ameliorates High-Fat-Diet-Induced Non-Alcoholic Fatty Liver Disease by Regulating Lipogenesis and Lipolysis Pathways

Non-alcoholic fatty liver disease (NAFLD) is now recognized as the most prevalent liver disease globally. Pea albumin (PA) has demonstrated positive impacts on reducing obesity and improving glucose metabolism. In this research, a mouse model of NAFLD induced by a high-fat diet (HFD) was employed to examine the impact of PA on NAFLD and explore its potential mechanisms. The findings revealed that mice subjected to a HFD developed pronounced fatty liver alterations. The intervention with PA significantly lowered serum TC by 26.81%, TG by 43.55%, and LDL-C by 57.79%. It also elevated HDL-C levels by 1.2 fold and reduced serum ALT by 37.94% and AST by 31.21% in mice fed a HFD. These changes contributed to the reduction in hepatic steatosis and lipid accumulation. Additionally, PA improved insulin resistance and inhibited hepatic oxidative stress and inflammatory responses. Mechanistic studies revealed that PA alleviated lipid accumulation in HFD-induced NAFLD by activating the phosphorylation of AMPKα and ACC, inhibiting the expression of SREBF1 and FASN to reduce hepatic lipogenesis, and increasing the expression of ATGL, PPARα, and PPARγ to promote lipolysis and fatty acid oxidation. These results indicate that PA could serve as a dietary supplement for alleviating NAFLD, offering a theoretical foundation for the rational intake of PA in NAFLD intervention.

Do iron homeostasis biomarkers mediate the associations of liability to type 2 diabetes and glycemic traits in liver steatosis and cirrhosis: a two-step Mendelian randomization study

BACKGROUND

Previous studies, including Mendelian randomization (MR), have demonstrated type 2 diabetes (T2D) and glycemic traits are associated with increased risk of metabolic dysfunction-associated steatotic liver disease (MASLD). However, few studies have explored the underlying pathway, such as the role of iron homeostasis.

METHODS

We used a two-step MR approach to investigate the associations of genetic liability to T2D, glycemic traits, iron biomarkers, and liver diseases. We analyzed summary statistics from various genome-wide association studies of T2D (n = 933,970), glycemic traits (n ≤ 209,605), iron biomarkers (n ≤ 246,139), MASLD (n ≤ 972,707), and related biomarkers (alanine aminotransferase (ALT) and proton density fat fraction (PDFF)). Our primary analysis was based on inverse-variance weighting, followed by several sensitivity analyses. We also conducted mediation analyses and explored the role of liver iron in post hoc analysis.

RESULTS

Genetic liability to T2D and elevated fasting insulin (FI) likely increased risk of liver steatosis (ORliability to T2D: 1.14 per doubling in the prevalence, 95% CI: 1.10, 1.19; ORFI: 3.31 per log pmol/l, 95% CI: 1.92, 5.72) and related biomarkers. Liability to T2D also likely increased the risk of developing liver cirrhosis. Genetically elevated ferritin, serum iron, and liver iron were associated with higher risk of liver steatosis (ORferritin: 1.25 per SD, 95% CI 1.07, 1.46; ORliver iron: 1.15 per SD, 95% CI: 1.05, 1.26) and liver cirrhosis (ORserum iron: 1.31, 95% CI: 1.06, 1.63; ORliver iron: 1.34, 95% CI: 1.07, 1.68). Ferritin partially mediated the association between FI and liver steatosis (proportion mediated: 7%, 95% CI: 2-12%).

CONCLUSIONS

Our study provides credible evidence on the causal role of T2D and elevated insulin in liver steatosis and cirrhosis risk and indicates ferritin may play a mediating role in this association.

Gynostemma pentaphyllum Extract Alleviates NASH in Mice: Exploration of Inflammation and Gut Microbiota

NASH (non-alcoholic steatohepatitis) is a severe liver disease characterized by hepatic chronic inflammation that can be associated with the gut microbiota. In this study, we explored the therapeutic effect of Gynostemma pentaphyllum extract (GPE), a Chinese herbal extract, on methionine- and choline-deficient (MCD) diet-induced NASH mice. Based on the peak area, the top ten compounds in GPE were hydroxylinolenic acid, rutin, hydroxylinoleic acid, vanillic acid, methyl vanillate, quercetin, pheophorbide A, protocatechuic acid, aurantiamide acetate, and iso-rhamnetin. We found that four weeks of GPE treatment alleviated hepatic confluent zone inflammation, hepatocyte lipid accumulation, and lipid peroxidation in the mouse model. According to the 16S rRNA gene V3-V4 region sequencing of the colonic contents, the gut microbiota structure of the mice was significantly changed after GPE supplementation. Especially, GPE enriched the abundance of potentially beneficial bacteria such as Akkerrmansia and decreased the abundance of opportunistic pathogens such as Klebsiella. Moreover, RNA sequencing revealed that the GPE group showed an anti-inflammatory liver characterized by the repression of the NF-kappa B signaling pathway compared with the MCD group. Ingenuity Pathway Analysis (IPA) also showed that GPE downregulated the pathogen-induced cytokine storm pathway, which was associated with inflammation. A high dose of GPE (HGPE) significantly downregulated the expression levels of the tumor necrosis factor-α (TNF-α), myeloid differentiation factor 88 (Myd88), cluster of differentiation 14 (CD14), and Toll-like receptor 4 (TLR4) genes, as verified by real-time quantitative PCR (RT-qPCR). Our results suggested that the therapeutic potential of GPE for NASH mice may be related to improvements in the intestinal microenvironment and a reduction in liver inflammation.

Mitochondrial quality control in human health and disease

Mitochondria, the most crucial energy-generating organelles in eukaryotic cells, play a pivotal role in regulating energy metabolism. However, their significance extends beyond this, as they are also indispensable in vital life processes such as cell proliferation, differentiation, immune responses, and redox balance. In response to various physiological signals or external stimuli, a sophisticated mitochondrial quality control (MQC) mechanism has evolved, encompassing key processes like mitochondrial biogenesis, mitochondrial dynamics, and mitophagy, which have garnered increasing attention from researchers to unveil their specific molecular mechanisms. In this review, we present a comprehensive summary of the primary mechanisms and functions of key regulators involved in major components of MQC. Furthermore, the critical physiological functions regulated by MQC and its diverse roles in the progression of various systemic diseases have been described in detail. We also discuss agonists or antagonists targeting MQC, aiming to explore potential therapeutic and research prospects by enhancing MQC to stabilize mitochondrial function.

Six-gene prognostic signature for non-alcoholic fatty liver disease susceptibility using machine learning

BACKGROUND

nonalcoholic fatty liver disease (NAFLD) is a common liver disease affecting the global population and its impact on human health will continue to increase. Genetic susceptibility is an important factor influencing its onset and progression, and there is a lack of reliable methods to predict the susceptibility of normal populations to NAFLD using appropriate genes.

METHODS

RNA sequencing data relating to nonalcoholic fatty liver disease was analyzed using the "limma" package within the R software. Differentially expressed genes were obtained through preliminary intersection screening. Core genes were analyzed and obtained by establishing and comparing 4 machine learning models, then a prediction model for NAFLD was constructed. The effectiveness of the model was then evaluated, and its applicability and reliability verified. Finally, we conducted further gene correlation analysis, analysis of biological function and analysis of immune infiltration.

RESULTS

By comparing 4 machine learning algorithms, we identified SVM as the optimal model, with the first 6 genes (CD247, S100A9, CSF3R, DIP2C, OXCT 2 and PRAMEF16) as predictive genes. The nomogram was found to have good reliability and effectiveness. Six genes' receiver operating characteristic curves (ROC) suggest an essential role in NAFLD pathogenesis, and they exhibit a high predictive value. Further analysis of immunology demonstrated that these 6 genes were closely connected to various immune cells and pathways.

CONCLUSION

This study has successfully constructed an advanced and reliable prediction model based on 6 diagnostic gene markers to predict the susceptibility of normal populations to NAFLD, while also providing insights for potential targeted therapies.

Molecular Mechanisms of Fucoxanthin in Alleviating Lipid Deposition in Metabolic Associated Fatty Liver Disease

Metabolic-associated fatty liver disease (MAFLD) is witnessing a global surge; however, it still lacks effective pharmacological interventions. Fucoxanthin, a natural bioactive metabolite derived from marine brown algae, exhibits promising pharmacological functions, particularly in ameliorating metabolic disorders. However, the mechanisms underlying its therapeutic efficacy in addressing MAFLD remain elusive. Our present findings indicated that fucoxanthin significantly alleviated palmitic acid (PA)-induced hepatic lipid deposition in vitro and obesity-induced hepatic steatosis in ob/ob mice. Moreover, at both the protein and transcriptional levels, fucoxanthin effectively increased the expression of PPARα and CPT1 (involved in fatty acid oxidation) and suppressed FASN and SREBP1c (associated with lipogenesis) in both PA-induced HepG2 cells and hepatic tissues in ob/ob mice. This modulation was accompanied by the activation of AMPK. The capacity of fucoxanthin to improve hepatic lipid deposition was significantly attenuated when utilizing the AMPK inhibitor or siRNA-mediated AMPK silencing. Mechanistically, fucoxanthin activates AMPK, subsequently regulating the KEAP1/Nrf2/ARE signaling pathway to exert antioxidative effects and stimulating the PGC1α/NRF1 axis to enhance mitochondrial biogenesis. These collective actions contribute to fucoxanthin's amelioration of hepatic steatosis induced by metabolic perturbations. These findings offer valuable insights into the prospective utilization of fucoxanthin as a therapeutic strategy for managing MAFLD.

Transketolase promotes MAFLD by limiting inosine-induced mitochondrial activity

Metabolic dysfunction-associated fatty liver disease (MAFLD) has a global prevalence of about 25% and no approved therapy. Using metabolomic and proteomic analyses, we identified high expression of hepatic transketolase (TKT), a metabolic enzyme of the pentose phosphate pathway, in human and mouse MAFLD. Hyperinsulinemia promoted TKT expression through the insulin receptor-CCAAT/enhancer-binding protein alpha axis. Utilizing liver-specific TKT overexpression and knockout mouse models, we demonstrated that TKT was sufficient and required for MAFLD progression. Further metabolic flux analysis revealed that Tkt deletion increased hepatic inosine levels to activate the protein kinase A-cAMP response element binding protein cascade, promote phosphatidylcholine synthesis, and improve mitochondrial function. Moreover, insulin induced hepatic TKT to limit inosine-dependent mitochondrial activity. Importantly, N-acetylgalactosamine (GalNAc)-siRNA conjugates targeting hepatic TKT showed promising therapeutic effects on mouse MAFLD. Our study uncovers how hyperinsulinemia regulates TKT-orchestrated inosine metabolism and mitochondrial function and provides a novel therapeutic strategy for MAFLD prevention and treatment.

Role of Angiotensin II in Non-Alcoholic Steatosis Development

Fatty liver is a multifactorial disease characterized by excessive accumulation of lipids in hepatocytes (steatosis), insulin resistance, oxidative stress, and inflammation. This disease has a major public health impact because it is the first stage of a chronic and degenerative process in the liver that can lead to steatohepatitis, cirrhosis, and liver cancer. Although this disease is mainly diagnosed in patients with obesity, type 2 diabetes mellitus, and dyslipidemia, recent evidence indicates that vasoactive hormones such as angiotensin II (ANGII) not only promote endothelial dysfunction (ED) and hypertension, but also cause fatty liver, increase adipose tissue, and develop a pro-steatotic environment characterized by a low-grade systemic pro-inflammatory and pro-oxidant state, with elevated blood lipid levels. The role of ANGII in lipid accumulation has been little studied, so this review aims to summarize existing reports on the possible mechanism of action of ANGII in inducing lipid accumulation in hepatocytes.