Pathogenesis of Nonalcoholic Steatohepatitis

Association between liver fibrosis and osteoporosis in adults aged 50 and older: insights from the Bushehr Elderly Health Program

Objectives

Both liver fibrosis and osteoporosis share inflammatory pathways, with liver fibrosis potentially contributing to decreased bone mineral density (BMD). The rising prevalence of non-alcoholic fatty liver disease (NAFLD) and associated liver fibrosis, especially in older populations, may increase the risk of osteoporosis, but evidence remains inconclusive. This study aims to investigate the relationship between liver fibrosis and osteoporosis in individuals over 50 years old.

Methods

This cross-sectional study used data from the Bushehr Elderly Health Program (BEHP), a cohort of 2,000 participants aged 50 and older, selected through multistage stratified random sampling. BMD and trabecular bone score (TBS) measurements were assessed. The Fibrosis-4 (FIB-4) index, a surrogate marker for liver fibrosis, was also calculated to examine its association with these bone health indicators. Multiple linear regression was applied to assess the relationship between FIB-4 and lumbar, hip, femoral neck BMD, and TBS scores, while logistic regression was used to evaluate osteoporosis as the dependent variable.

Results

A total of 1,959 participants with adequate data were included in our analysis. 538 participants had osteoporosis, 936 participants had osteopenia, and 485 participants had normal bone density. FIB-4 index was higher in osteoporotic groups (1.45 ± 0.90) than in osteopenic (1.26 ± 0.58, p < 0.001) and normal groups (1.17 ± 0.48, p < 0.001). After controlling for confounders, FIB-4 index was negatively associated with hip BMD (βmen=-0.0162; 95% CI: -0.0313, -0.0012 and βwomen=-0.0221; 95% CI: -0.0340, -0.0102), femoral neck BMD (βmen=-0.0216; 95% CI: -0.0356, -0.0076 and βwomen=-0.0233; 95% CI: -0.0342, 0.0124), and TBS (βmen=-0.0154; 95% CI: -0.0264, -0.0043 and βwomen=-0.0244; 95% CI: -0.0338, -0.0149) in both genders and with lumbar BMD in women (β=-0.0176; 95% CI: -0.0307, -0.0045). An increase in the FIB-4 index was associated with more than a twofold rise in the risk of developing osteoporosis in women (OR = 2.123; 95% CI: 1.503, 3.000; p < 0.001) and a 36% higher risk in men (OR = 1.366; 95% CI: 1.012, 1.844; p = 0.042).

Conclusions

Liver fibrosis is associated with decreased bone density and attenuated bone architecture. Elevated FIB-4 index has been identified as a risk factor for osteoporosis, indicating a potential link between liver fibrosis and deteriorating bone health.

Exploring the Prevalence and Risk Factors of MASLD in Patients with Newly Diagnosed Diabetes Mellitus: A Comprehensive Investigation

Background: Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) represents a growing concern in the context of metabolic disorders, particularly among individuals diagnosed with type 2 diabetes mellitus (T2DM). This study aimed to investigate the prevalence of MASLD among newly diagnosed T2DM patients and identify the risk factors for MASLD in this population. Methods: This prospective study included 128 patients with newly diagnosed T2DM between January 2022 and June 2023. Demographic, clinical, anthropometric (BMI, waist circumference), and laboratory data (glucose, HbA1c, lipid profile, ALT, AST, creatinine, platelet count) were collected. MASLD was diagnosed based on ultrasonographic evidence of hepatic steatosis with at least one cardiometabolic risk factor after excluding other causes. Linear regression models were used to determine independent predictors. Results: MASLD was detected in 80.4% of patients. Compared with the MASLD (-) group, the MASLD (+) group had significantly higher ALT (47.1 ± 23 U/L vs. 24.9 ± 8 U/L, p < 0.001) and non-HDL cholesterol (189 ± 57 mg/dL vs. 167 ± 28 mg/dL, p = 0.047). Spearman correlation showed positive associations of MASLD severity with waist circumference, LDL cholesterol, and platelet count. ALT and BMI were independently associated with MASLD in linear regression analysis. Conclusions: This study underscores the significant prevalence of MASLD in newly diagnosed T2DM patients, emphasizing the relevance of early detection in addressing this common comorbidity in the diabetic population.

Disrupted minor intron splicing activates reductive carboxylation-mediated lipogenesis to drive metabolic dysfunction-associated steatotic liver disease progression

Aberrant RNA splicing is tightly linked to diseases, including metabolic dysfunction-associated steatotic liver disease (MASLD). In this study, we revealed that minor intron splicing, a unique and conserved RNA processing event, is largely disrupted upon the progression of metabolic dysfunction-associated steatohepatitis (MASH) in mice and humans. We demonstrated that deficiency of minor intron splicing in the liver induced MASH transition upon obesity-induced insulin resistance and LXR activation. Mechanistically, inactivation of minor intron splicing led to minor intron retention of Insig1 and Insig2, resulting in premature termination of translation, which drove proteolytic activation of SREBP1c. This mechanism was conserved in patients with MASH. Notably, disrupted minor intron splicing activated glutamine reductive metabolism for de novo lipogenesis through induction of Idh1, which caused accumulation of ammonia in the liver, thereby initiating hepatic fibrosis upon LXR activation. Ammonia clearance or IDH1 inhibition blocked hepatic fibrogenesis and mitigated MASH progression. More importantly, overexpression of Zrsr1 restored minor intron retention and ameliorated the development of MASH, indicating that dysfunctional minor intron splicing is an emerging pathogenic mechanism that drives MASH progression. Additionally, our results suggest that reductive carboxylation flux triggered by minor intron retention in hepatocytes serves as a crucial checkpoint and potential target for MASH therapy.

Modulation of Cuproptosis Pathway Genes (DLAT, FDX1) and Antioxidant Enzyme Activities in Obese Mice in Response to Quercetin and Calorie Restriction

Cuproptosis is a new mode of cell death that is closely related to mitochondrial stress. The purpose of this study is to investigate the amount of copper, copper-associated genes DLAT and FDX1 oxidative stress (OS) status in obesity. Since there is a close relationship between OS and cuproptosis, evaluating the effect of various strategies to reduce OS, including quercetin (QUER) and caloric restriction (CR), is another goal of this study. In this study, 30 male BALB-C mice aged 8 weeks and weighing 25 g, including the groups receiving normal diet (ND), ND with QUER (15 mg/kg, IP) and CR, a high-fat diet (HFD) with the QUER, CR or a combination of both were used. The activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione reductase (GR), amount of copper in the liver and kidney tissues, and expression of DLAT and FDX1 genes were measured in all studied groups. The amount of copper in the liver and kidney tissue as well as the expression of FDX1 and DLAT in the HFD group increased significantly compared with the ND group. QUER, CR or their combination could significantly reduce the amount of copper as well as the expression of FDX1 and DLAT in liver and kidney tissues. QUER and CR, also significantly increased the activity of GR, SOD and GPX in serum, liver, and kidney tissues. Based on the results, QUER, CR and especially the simultaneous use of both, was able to reduce the amount of copper and its related cuproptosis. These effects may reduce cuproptosis-associated cell death. Therefore, the use of antioxidants and CR may be a promising solution to protect the human body against the effects of cuproptosis in conditions like obesity.

Network pharmacology and transcriptomics reveal Complanatoside A regulates lipid metabolism in hyperlipidemia and non-alcoholic fatty liver disease via the AMPK pathway

Non-alcoholic fatty liver disease (NAFLD) and hyperlipidemia belong to the metabolic disorder syndromes of metabolic syndrome. They share a common pathological basis and are often complicated. Complanatoside A (CA), a flavonoid abundant in Astragali complanati semen, helps to prevent NAFLD and hyperlipidemia. However, the exact molecular mechanism is uncertain. Therefore, this study aims to explore the core mechanism. Network pharmacology was used to analyze the preventive mechanism of CA against NAFLD and hyperlipidemia. The efficacy of CA was proven in a high-fat diet-fed mouse model and a steatogenic hepatocyte model. Transcriptomic analysis, Western blot validation, and molecular docking methods were used to explore the common mechanism of CA in preventing NAFLD and hyperlipidemia. Network pharmacology revealed that the AMP-activated protein kinase (AMPK) pathway is a common mechanism leading to NAFLD and hyperlipidemia. It is also a potential pathway by which CA exerts its protective effect, which was confirmed in transcriptomics in vivo. Both in vitro and in vivo experiments showed that CA could inhibit lipid synthesis and promote fatty acid oxidation by activating the AMPK, alleviating lipid accumulation, and lipotoxic liver injury. This was demonstrated by the use of an AMPK inhibitor in vitro. Furthermore, molecular docking results showed that CA could directly interact with AMPK to regulate downstream lipid-related proteins. In conclusion, the AMPK pathway is key in developing NAFLD and hyperlipidemia. CA plays a dual preventive role in NAFLD and hyperlipidemia by activating AMPK to regulate lipid metabolism.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Lipogenesis and MASLD: re-thinking the role of SREBPs

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide and a major risk factor for hepatocellular carcinoma (HCC). Lipid metabolism, particularly de novo lipogenesis (DNL) regulated by sterol regulatory element-binding proteins (SREBPs), plays a key role in MASLD progression. While excessive SREBP activation contributes to hepatic steatosis, our recent findings indicate that strong SREBP inhibition paradoxically exacerbates liver injury and accelerates carcinogenesis in murine MASLD models. Mechanistically, SREBP dysfunction disrupts phospholipid homeostasis, leading to impaired endoplasmic reticulum (ER) membrane fluidity, ER stress, and hepatocyte injury. Transcriptomic analysis of clinical samples revealed a dynamic shift in SREBP activity, with upregulation in early MASLD but significant downregulation in advanced, burned-out MASH. This suggests that SREBP dysfunction in advanced disease may contribute to fibrosis progression and increased HCC risk. Given these findings, therapeutic strategies targeting lipid metabolism in MASLD must be carefully tailored to disease stage. This review provides an updated perspective on the biphasic role of SREBP in MASLD, emphasizing the need to re-think lipid metabolism-targeted therapies and develop personalized interventions to mitigate disease progression and HCC development.

Trends in the applications of artificial intelligence in fatty liver diseases

INTRODUCTION

Artificial intelligence (AI) has rapidly advanced and shows great potential in the prediction, diagnosis, treatment, and prognosis of fatty liver disease (FLD). This study aims to summarize AI's applications and emerging trends in FLD to inspire future research directions.

METHOD

We analyzed 270 articles sourced from the Web of Science Core Collection published between 2006 and 2024. The study focuses on the medical application of AI in FLD, examining the contributions of authors, institutions, countries, keywords, and cited references.

RESULTS

AI is predominantly applied in FLD diagnosis, with progression from simple diagnostic tools to advanced methods for classifying FLD and assessing liver fat content. Moreover, the types of data used in AI development have evolved, incorporating a variety of new image and clinical data sources. AI is also being integrated into drug development and personalized nutritional therapies for FLD. Additionally, researchers are becoming increasingly interested in the application of AI to study FLD genes.

CONCLUSION

We found that the applications of AI in FLD are mainly reflected in the prediction, diagnosis, therapy, and prognosis of FLD. In contrast to traditional medicine, AI has the potential to advance the fields of precision medicine and telemedicine, as well as to conserve additional social resources. Moreover, AI may help medical personnel from the perspective of traditional Chinese medicine, FLD prognosis, and the use of AI to analyze gene prediction and natural language processing (NLP).

Addressing the High and Rising Global Burden of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) and Metabolic Dysfunction-Associated Steatohepatitis (MASH): From the Growing Prevalence to Payors' Perspective

BACKGROUND

The continuum of metabolic syndrome encompasses a spectrum of dysfunctions impacting obesity-linked insulin resistance, glucose homeostasis, lipid metabolism and pro-inflammatory immune responses. The global prevalence of metabolic diseases, including diabetes, chronic liver disease, cardiometabolic disease and kidney disease, has surged in recent decades, contributing significantly to population mortality. Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease, is a leading cause of liver disease worldwide. MASLD poses a significant global health challenge with its rising prevalence, placing a substantial burden on healthcare systems, impacts patient well-being and incurs significant economic costs. Addressing MASLD requires a comprehensive understanding of its interconnected factors, including its prevalence, healthcare burden and economic implications. Lack of awareness, imprecise non-invasive diagnostic methods and ineffective preventive interventions are core components of the MASLD-related problem.

AIM

The aim of this article was to summarise the global burden of MASLD from the payer's perspective.

METHODS

We carried out a review of the global comprehensive burden of MASLD. These topics led to discussions and insights by an expert panel during the 7th Metabolic Continuum Roundtable meeting, which took place in November 2023. This meeting focused on the burden, patient-reported outcomes and health economics, from payor and societal perspectives, and aimed to identify opportunities for improving patient care, optimise resource allocation and mitigate the overall impact on individuals and society related to MASLD. During the roundtable, an emphasis emerged on the need for greater awareness and strategic deployment of diagnostic, therapeutic and preventative measures to address MASLD effectively.

CONCLUSION

The global burden of MASLD is high and growing. Prioritising the prevention of metabolic dysregulation and timely therapeutic interventions can yield a holistic strategy to combat MASLD, its progression and potentially lower disease costs.

TRIAL REGISTRATION

NCT06309992.

Hepatic IL22RA1 deficiency promotes hepatic steatosis by modulating oxysterol in the liver

BACKGROUND AND AIMS

An imbalance in lipid metabolism is the main cause of NAFLD. While the pathogenesis of lipid accumulation mediated by extrahepatic regulators has been extensively studied, the intrahepatic regulators modulating lipid homeostasis remain unclear. Previous studies have shown that systemic administration of IL-22 protects against NAFLD; however, the role of IL-22/IL22RA1 signaling in modulating hepatic lipid metabolism remains uncertain.

APPROACH AND RESULTS

This study shows that hepatic IL22RA1 is vital in hepatic lipid regulation. IL22RA1 is downregulated in palmitic acid-treated mouse primary hepatocytes, as well as in the livers of NAFLD model mice and patients. Hepatocyte-specific Il22ra1 knockout mice display diet-induced hepatic steatosis, insulin resistance, impaired glucose tolerance, increased inflammation, and fibrosis compared with flox/flox mice. This is attributed to increased lipogenesis mediated by the accumulation of hepatic oxysterols, particularly 3 beta-hydroxy-5-cholestenoic acid (3β HCA). Mechanistically, hepatic IL22RA1 deficiency facilitates 3β HCA deposition through the activating transcription factor 3/oxysterol 7 alpha-hydroxylase axis. Notably, 3β HCA facilitates lipogenesis in mouse primary hepatocytes and human liver organoids by activating liver X receptor-alpha signaling, but IL-22 treatment attenuates this effect. Additionally, restoring oxysterol 7 alpha-hydroxylase or silencing hepatic activating transcription factor 3 reduces both hepatic 3β HCA and lipid contents in hepatocyte-specific Il22ra1 knockout mice.

CONCLUSIONS

These findings indicate that IL22RA1 plays a crucial role in maintaining hepatic lipid homeostasis in an activating transcription factor 3/oxysterol 7 alpha-hydroxylase-dependent manner and establish a link between 3β HCA and hepatic lipid homeostasis.

Disulfiram in liver diseases: a double-edged sword

Disulfiram, a synthetic drug, has historically played a significant role in the treatment of alcoholic liver disease as the first medication approved by the U.S. Food and Drug Administration for alcohol use disorders. Beyond its efficacy in inhibiting alcohol addiction and treating alcoholic liver disease, disulfiram has also demonstrated potential in managing various liver conditions, including certain metabolic liver injuries and liver cancer. As an established, cost-effective drug with well-documented synthesis methods, disulfiram holds promise for broader application in liver disease treatment. However, its clinical use is hindered by the risk of inducing pharmacologic liver injury. This potential for liver toxicity necessitates careful patient selection, monitoring, and consultation with healthcare providers, which can limit its practicality in treating patients with existing liver conditions. This review aims to analyze the multifaceted role of disulfiram in liver diseases comprehensively. By exploring its therapeutic efficacy, potential benefits, and inherent limitations, we seek to provide a balanced perspective that maximizes disulfiram's therapeutic potential while ensuring the safety and well-being of patients. This thorough examination will also highlight areas for future research, paving the way for optimized treatment protocols that incorporate disulfiram in the context of liver disease management.

Metabolic dysfunction-associated steatotic liver disease and omega-6 polyunsaturated fatty acids: Friends or foes

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide. Its prevalence is closely linked to the dramatic rise in obesity and non-communicable diseases. MASLD exhibits a progressive trajectory that may culminate in development of hepatic cirrhosis, thereby predisposing affected individuals to an elevated likelihood of hepatocarcinogenesis. Diet, especially dietary fatty acids, serves as a key link between nutrient intake and MASLD pathogenesis.

AIM

To explore the impact of various omega-6 fatty acid subtypes on the pathogenesis and therapeutic strategies of MASLD.

METHODS

A systematic literature search was conducted across Web of Science, PubMed, Cochrane Central, Scopus, and Embase databases from inception through June 2024 to identify all original studies linking different subtypes of omega-6 polyunsaturated fatty acids to the pathogenesis and management of MASLD. The search strategy explored the linkage between omega-6 polyunsaturated fatty acids and their subtypes, including linoleic acid (LA), gamma-linolenic acid (GLA), arachidonic acid, conjugated LA, and docosapentaenoic acid, in relation to MASLD and cardiometabolic risk.

RESULTS

By employing the specified search strategy, a total of 83 articles were identified as potentially eligible. During the title, abstract, and full-text screening phases, 27 duplicate records were removed, leaving 56 records for relevance screening. Of these, 43 records were excluded for reasons such as irrelevance and language restrictions (limited to English), resulting in 13 full-text articles being included for detailed assessment (10 human studies,1 animal study, and 2 review articles). Although certain subtypes, as GLA, dihomo-GLA, omega-6-derived oxylipins, and most arachidonic acid-derived eicosanoids, exhibit pro-inflammatory effects, our findings suggest that other subtypes such as LA, cis-9, trans-11 conjugated LA, and docosapentaenoic acid have beneficial effects on fatty liver, cardiometabolic risk factors, and inflammation, even at high intake levels.

CONCLUSION

The varying health effects of omega-6 fatty acids, ranging from anti-inflammatory to pro-inflammatory impacts on the liver, leave the question of their recommendation for MASLD patients unresolved. This underscores the importance of careful selection when considering omega-6 supplementation.

Mechanisms of rifaximin inhibition of hepatic fibrosis in mice with metabolic dysfunction associated steatohepatitis through the TLR4/NFκB pathway

Metabolic dysfunction-associated steatohepatitis (MASH) has become a serious public health problem, posing an increasingly dangerous threat to human health owing to its increasing prevalence and accompanying intra- and extrahepatic adverse outcomes. Rifaximin is considered to have therapeutic potential for MASH; however, its efficacy remains controversial. Our study aimed to observe the ameliorative effects of rifaximin and explore its possible mechanisms at the cellular level. 1. 42 male C57BL/6J mice were divided into 3 groups, the CON group and MCD group were fed with normal feed and MCD feed for 12 weeks respectively, and the MCD + RFX group was treated with rifaximin by gavage for 4 weeks on the basis of MCD feed. Hematoxylin-eosin staining, Sirius red staining and immunohistochemical staining were used to observe the histopathological changes of liver and intestine. Differences in liver transaminases, inflammatory factors, fibrosis indexes and intestinal tight junction proteins were compared among the 3 groups of mice. 2. A MASH cell model was constructed by inducing HepG2 cells with free fatty acids to observe the effects of rifaximin on MASH in vitro. In addition, the effects of rifaximin on TLR4/NF-κB signaling pathway were explored by applying TLR4 agonist LPS and TLR4 inhibitor TAK-242. Hepatic histopathology was significantly improved in MASH mice after rifaximin treatment, and their serum alanine aminotransferase and aspartate aminotransferase levels were (72.72 ± 5.68) U/L and (222.8 ± 11.22) U/L, respectively, which were significantly lower than those in the MCD group [(293.3 ± 10.69) U/L and (414.1 ± 36.29) U/L, P < 0.05], and the levels of inflammatory factors and fibrosis indicators were reduced. Rifaximin ameliorated intestinal barrier injury with increased expression of intestinal tight junction protein ZO-1 in the MCD + RFX group of mice, and the concentration of LPS-binding proteins (4.92 ± 0.55 vs. 15.82 ± 1.71, P < 0.05) was lower than that in the MCD group. In the NASH cell model, rifaximin similarly exerted inhibitory effects on its inflammatory factors and TLR4/NF-κB signaling pathway. Application of TLR4 inhibitors weakened the inhibitory effect of rifaximin on MASH. Our study supports rifaximin as a potential treatment for MASH, with potential mechanisms related to improving intestinal barrier integrity and downregulating the TLR4/NF-κB signaling pathway.

A Mendelian randomization study reveals a causal association between NASH and the risk of atrial fibrillation

Background

Epidemiological evidence suggests that non-alcoholic fatty liver disease (NAFLD) may increase the risk of atrial fibrillation (AF). However, the findings are inconsistent, and the causality remains to be established.

Methods

We conducted two-step, two-sample Mendelian randomization (MR) analysis to assess the association between genetically predicted NAFLD (i.e. chronically elevated serum alanine aminotransferase levels [cALT], imaging-based and biopsy-confirmed NAFLD) and AF. Subsequently, we further performed Mendelian randomization to investigate the causal relationship between non-alcoholic steatohepatitis (NASH), a subtype of NAFLD, and AF. The inverse variance weighted (IVW) method was used as the primary approach to reveal the potential causation between the exposure and outcome.

Results

There was no significant causal association between NAFLD diagnosed based on cALT, confirmed by imaging, or verified by biopsy, and an increased risk of atrial fibrillation. Furthermore, the results of the IVW method revealed a positive causal effect of NASH on AF (OR=1.113, 95% CI=1.025-1.209, P = 0.011). In the reverse analysis, however, no evidence supported a significant genetic association between AF and NASH (OR=0.974, 95% CI=0.934-1.016, P = 0.214).

Conclusion

A causal relationship existed between NASH and the risk of AF. However, no significant genetic association has been observed between NAFLD and AF risk. This suggests that managing the progression of NAFLD may hold potential value in preventing the onset of AF.

Novel translational mouse models of metabolic dysfunction-associated steatotic liver disease comparable to human MASLD with severe obesity

OBJECTIVE

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common cause of chronic liver disease, especially in patients with severe obesity. However, current mouse models for MASLD do not reflect the polygenetic background nor the metabolic changes in this population. Therefore, we investigated two novel mouse models of MASLD with a polygenetic background for the metabolic syndrome.

METHODS

TALLYHO/JngJ mice and NONcNZO10/LtJ mice were fed a high-fat- high-carbohydrate (HF-HC) diet with a surplus of cholesterol diet. A second group of TH mice was additional treated with empagliflozin.

RESULTS

After sixteen weeks of feeding, both strains developed metabolic syndrome with severe obesity and histological manifestation of steatohepatitis, which was associated with significantly increased intrahepatic CD8+cells, CD4+cells and Tregs, contributing to a significant increase in pro-inflammatory and pro-fibrotic gene activation as well as ER stress and oxidative stress. In comparison with the human transcriptomic signature, we could demonstrate a good metabolic similarity, especially for the TH mouse model. Furthermore, TH mice also developed signs of kidney injury as an extrahepatic comorbidity of MASLD. Additional treatment with empagliflozin in TH mice attenuates hepatic steatosis and improves histological manifestation of MASH.

CONCLUSIONS

Overall, we have developed two promising new mouse models that are suitable for preclinical studies of MASLD as they recapitulate most of the key features of MASLD.

Sex-specific effects of aged polystyrene microplastics on hepatic AMPK pathway activation and lipid droplet accumulation in MAFLD mice

Microplastics (MPs) are environmental pollutants attracting widespread attention due to their environmental omnipresence and potential health effects. MPs undergo ageing in the environment and our previous research found that aged Polystyrene microplastics (PS-MPs) affected lipid metabolism in healthy female mice, but not males. In this study, we examined the effects of aged PS-MP exposure on lipid metabolism in mice with Metabolic Associated Fatty Liver Disease (MAFLD). 14 female and 14 male mice were furnished with a high-fat diet (HFD) for eight weeks to create MAFLD model mice. They were then orally administered aged PS-MPs for four weeks, and changes in the AMP-activated protein kinase signalling pathway were examined in order to determine PS-MP's effect on hepatic metabolism. The outcomes showed that though serum estradiol, inflammatory gene expression and ROS levels increased significantly in both male and female HFD-aged PS-MP groups, hepatic steatosis was attenuated only in the female group. Furthermore, serum ERα, ERβ, AMPKα, acetyl-CoA carboxylase, sterol regulatory element binding protein-1c, and Fas expressions were significantly increased in the MAFLD mice groups compared to the control group. Combining serum E2 levels, AMPK pathway changes, oxidative stress markers, and inflammatory gene levels, aged PS-MPs may stimulate E2 production and mobilize the liver AMPK signalling pathway of both male and female MAFLD mice. However, lipid metabolism is only affected in female MAFLD mice, suggesting other possible mechanisms besides the AMPK pathway may be at play. These results provide a new perspective on the potential health effects of MP exposure in individuals with metabolic disorders such as MAFLD.

Identification of chikusetsusaponin IVa as a novel lysine-specific demethylase 1 inhibitor that ameliorates high fat diet-induced MASLD in mice

Diet-induced metabolic dysfunction steatotic liver disease (MASLD) is also called as non-alcoholic fatty liver disease (NAFLD) with limited effective strategies available. We previously have shown that chikusetsusaponin IVa (CHS), a dietary saponin from herbs in South American known for their metabolic benefits, mitigates diet-induced diabetes. In this study we investigated the beneficial effects of CHS on MASLD and the underlying mechanisms. MAFLD mouse model was established by the high-fat diet (HFD) for 6 weeks and then were treated with CHS (50 mg·kg-1·d-1, i.g.) for another 8 weeks. By conducting transcriptomic analysis in palmitic acid-treated HepG2 cells and primary hepatocytes as well as lipidomic analysis in liver tissues, we demonstrated that HFD activated the intestinal farnesoid X receptor (FXR) pathway, leading to the release of FGF15/19, which in turn promoted hepatic FXR-SHP binding with cAMP-responsive element-binding protein H (CREBH), thereby inhibiting CREBH-mediated fatty acid oxidation (FAO) and ketogenesis. Intriguingly, we found that CHS improved lipid metabolism in HFD mice by suppressing the enterohepatic crosstalk of FXR-SHP to enhance CREBH transactivation. Among these, lysine-specific demethylase 1 (LSD1)-mediated histone demethylation played a crucial role in lipid metabolic reprogramming. Moreover, we identified LSD1 as a critical cellular target of CHS, directly binding to Lys661 and Tyr761 of LSD1 to inhibit its histone demethylation activity. Our results suggest that targeting intestinal LSD1 with CHS could be a promising strategy for MAFLD treatment, offering new insights into the bioavailability and efficacy of natural products.

Clinical Assessment of Common Medications for Nonalcoholic Fatty Liver Disease: A Systematic Review and Bayesian Network Meta-Analysis

OBJECTIVE

With a steadily rising prevalence, nonalcoholic fatty liver disease (NAFLD) was a leading global cause of liver-related health problems. In the clinical management of NAFLD, various western pharmaceuticals were widely utilized. This network meta-analysis aimed to evaluate the effectiveness of common western medications for NAFLD patients.

METHODS

We systematically reviewed and screened articles based on predesigned criterion about western medications for NAFLD, which were from Embase, Cochrane Library, PubMed, CNKI, WanFang, and China Science and Technology Journal Database until August 1, 2024. Eligible studies included randomized controlled trials of patients aged 18 or older with NAFLD, comparing Western medicines to placebos or other Western medicine treatments. The risk of bias assessment tool 2.0 from the Cochrane system was used to assess the quality of the included articles. A Bayesian network meta-analysis was conducted using WinBUGS 1.4.3 with a random-effects model and Markov Chain Monte Carlo methods. Treatment rankings were based on Surface Under the Cumulative Ranking Curve (SUCRA) values, and heterogeneity was assessed with I2 and Q statistics. The outcomes were analyzed in WinBUGS and visualized using Stata 14.0, generating network plots and cumulative probability rankings to compare treatment effects. The systematic review was registered in PROSPERO (CRD42024509176).

RESULTS

Based on 37 included articles involving 7673 patients, pioglitazone demonstrated the most significant effects in resolving nonalcoholic steatohepatitis without worsening fibrosis, increasing high-density lipoprotein cholesterol levels, and achieving a ≥ 2-point reduction in NAFLD activity scores (odds ratio [OR] = 0.09, 95% confidence interval [CI]: 0.01 to 0.81), with a SUCRA probability of 91.4%. Aldafermin showed remarkable effects in improving liver function markers, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyl transpeptidase, with cumulative probabilities of 90% for ALT and 69.8% for AST. Cluster analysis revealed that Resmetirom and Aldafermin were superior options for enhancing liver function, while pioglitazone emerged as the best treatment for the comprehensive improvement of NAFLD.

CONCLUSIONS

Pioglitazone outperformed other western medicines in terms of overall efficacy when treating NAFLD, but Aldafermin and Resmetirom showed superior improvement in liver function. This study provided a certain level of support for the use of specific clinical medications.

Reactive Dicarbonyl Scavenging with 2-Hydroxybenzylamine Improves MASH

Background: Products of lipid peroxidation include a number of reactive lipid aldehydes including reactive dicarbonyl electrophiles (DEs) and contribute to disease processes. DEs play a significant role in the development and progression of metabolic-associated steatotic liver disease (MASLD) by contributing to oxidative stress, inflammation, protein dysfunction, and mitochondrial impairment. Reducing DE stress may be a potential strategy for managing MASLD. We hypothesized that the DE scavenger 2-hydroxybenzylamine (2-HOBA) would reduce liver injury by reducing liver protein adduct formation by DE in mouse models of MASLD. Methods: Protein adducts were measured in human livers by immunohistochemistry and immunoblot. The effects of 2-HOBA were assessed in two different mouse models of MASLD. Results: Isolevuglandin (IsoLG) protein adducts were increased in MASH-staged human livers relative to histologically normal controls. Diet-Induced Animal Model of Nonalcoholic Fatty Liver Disease (DIAMOND) mice treated with 2-HOBA exhibited significantly lower fibrosis scores (* p = 0.012) and reduced liver transaminases (AST, p = 0.03) and ALT, p = 0.012) by over 40%. In STAM (Stelic Animal Model) mice, 2-HOBA improved NAFLD activity scores (p = 0.03, NAS), hyperglycemia, and inflammatory cytokines and reduced serum F2-isoprostanes (IsoPs) by 30%, p = 0.05. These improvements were absent mRNA changes in hepatic antioxidant enzymes (Cat, Gpx1, or Sod2) or ROS-generating proteins (p22PHOX, p47PHOX, NOX4 or COX1). Conclusions: DE scavenging with 2-HOBA may be a promising therapeutic strategy for managing MASLD. While findings are currently limited to male mice, a nutraceutical that reduces liver fibrosis could significantly improve the management of MASH by offering a non-invasive treatment option to potentially slow or reverse liver scarring, delay progression to cirrhosis, and improve patient outcomes, while also providing a potential treatment option for patients who may not be suitable for other interventions like liver transplantation.

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.

Correlation between liver fibrosis in non-alcoholic fatty liver disease and insulin resistance indicators: a cross-sectional study from NHANES 2017-2020

Introduction

Non-alcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease worldwide, with liver fibrosis (LF) being a crucial pathological feature in the progression of NAFLD. Insulin resistance (IR) is believed to play an important role in the pathogenesis of NAFLD and the development of LF. This study aims to explore the relationship between various IR indicators and LF in patients with NAFLD.

Methods

This study utilized data from the National Health and Nutrition Examination Survey 2017-2020 cycles. Liver steatosis and fibrosis were assessed using liver ultrasound transient elastography. To assess the association between multiple IR indicators and LF, the study methodology included univariate and multivariate logistic regression, as well as restricted cubic spline (RCS) analysis. Subsequently, we used multivariate logistic regression to develop and validate a predictive model for LF, and evaluated the model's performance using the area under the curve (AUC) and calibration curve.

Results

A total of 904 patients were included in the final analysis. Among these NAFLD patients, 153 (16.92%) had LF. Compared to non-LF patients, LF patients had significantly higher body mass index (BMI), waist circumference (WC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), HbA1c, and fasting blood glucose (FBG) levels (all p < 0.05). Analysis of IR indicators showed that LF patients had significantly higher levels of TyG, TyG-WHtR, TyG-BMI, TyG-WC, TyG-GGT, METS-IR, and HOMA-IR (all p < 0.05). After adjusting for covariates, TyG-WHtR remained an independent risk factor (OR=2.69; 95% CI: 2.08-3.47), indicating a strong correlation with LF. The developed nomogram, incorporating AST, TyG, TyG-BMI, and diabetes, showed an AUC of 0.809 (95% CI: 0.771-0.847), indicating good predictive performance for LF in NAFLD patients.

Conclusions

This study confirms that a significant association between various IR and LF in NAFLD patients, and the developed nomogram provides a practical tool for early risk assessment. These findings underscore the clinical value of incorporating IR indices into routine practice to identify high-risk patients, enabling timely interventions to prevent fibrosis progression and improve outcomes.

Smad4 deficiency in hepatocytes attenuates NAFLD progression via inhibition of lipogenesis and macrophage polarization

Nonalcoholic fatty liver disease (NAFLD), a major cause of chronic liver disorders, has become a serious public health issue. Although the Smad4 signaling pathway has been implicated in the progression of NAFLD, the specific role of Smad4 in hepatocytes in NAFLD pathogenesis remains unclear. Hepatocyte-specific knockout Smad4 mice (AlbSmad4-/-) were first constructed using the Cre-Loxp recombinant system to establish a high-fat diet induced NAFLD model. The role of Smad4 in the occurrence and development of NAFLD was determined by monitoring the body weight of mice, detecting triglycerides and free fatty acids in serum and liver tissue homogenates, staining the tissue sections to observe the accumulation of liver fat, and RT-qPCR detecting the expression of genes related to lipogenesis, fatty acid intake, and fatty acid β oxidation. The molecular mechanism of Smad4 in hepatocytes affecting NAFLD was therefore investigated through combining in vitro and in vivo experiments. Smad4 deficiency in hepatocytes mitigated NAFLD progression and decreased inflammatory cell infiltration. Moreover, Smad4 deficiency inhibited CXCL1 secretion by suppressing the activation of the ASK1/P38/JNK signaling pathway. Furthermore, targeting CXCL1 using CXCR2 inhibitors diminished hepatocyte lipogenesis and inhibited the polarization of M1-type macrophages. Collectively, these results suggested that Smad4 plays a vital role in exacerbating NAFLD and may be a promising candidate for anti-NAFLD therapy.

Water-Soluble Cellulose Acetate Changes the Intestinal Microbiota in Mice with Non-Alcoholic Steatohepatitis

Objectives: Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic disorder of the liver and affects many people worldwide. Intestinal bacteria are thought to be involved in the pathological progression of NAFLD; therefore, improving the intestinal microbiota may be important in controlling NAFLD. In this study, we assessed the effects of water-soluble cellulose acetate (WSCA) on the intestinal microbiota in a non-alcoholic steatohepatitis (NASH) mouse model. Methods: NASH model (STAM mice) was created by streptozotocin injection and feeding the mice a high-fat diet. The serum biochemical parameters were analyzed. Intestinal bacterial populations were analyzed using paired-end sequencing of 16S rRNA, 18S rRNA, and internal transcribed spacer gene. Results: Our findings indicated that WSCA administration tends to improve the serum alanine aminotransferase and glucose levels in STAM mice and decreased the alpha diversity and altered the beta diversity of their intestinal microbiota. Additionally, WSCA intake resulted in an increase in the abundance of Coriobacteriaceae_UCG-002 and a decrease in the abundance of Enterobacter. Conclusions: WSCA intake can alter specific microbial compositions to improve blood glucose levels and liver functions and may improve the pathogenesis of NAFLD.

Protective role of ginsenoside Rg1 in the dynamic progression of liver injury to fibrosis: a preclinical meta-analysis

Background

The pathological progression from liver injury to fibrosis is a hallmark of liver disease, with no effective strategies to halt this transition. Ginsenoside Rg1 has demonstrated a range of hepatoprotective properties; however, systematic preclinical evidence supporting its therapeutic potential for liver injury and fibrosis remains limited. Purpose. This study evaluated the efficacy and underlying mechanisms of ginsenoside Rg1 in animal models of liver injury and fibrosis, and providing a basis for future clinical investigation.

Methods

A systematic review was conducted on preclinical studies published in PubMed, Web of Science, and Embase databases up to 1 August 2024, adhereing to rigorous quality standards. The methodological quality was assessed using SYRCLE's risk of bias tool. Meta-analysis and subgroup analysis were performed using Revman 5.4 software, while publication bias was evaluated through funnel plots and Egger's test in STATA 15.0 software. Additionally, a time-dose interval curve was utilized to assess the dose-response relationship and identify the effective dose of ginsenoside Rg1 for treating liver injury and fibrosis.

Results

Twenty-four trials involving 423 animals were included. The findings indicated that ginsenoside Rg1 significantly improved liver function markers (ALT and AST), reduced pathological indicators associated with liver injury and fibrosis, and lowered liver fibrosis-related markers (α-SMA, HYP, and PCIII). Furthermore, it exhibited beneficial effects on mechanistic indicators of inflammation, oxidative stress, and apoptosis, compared to the control group (P < 0.05). Time-dose interval analysis revealed that the effective dose range of ginsenoside Rg1 was between 4 and 800 mg/kg/d.

Conclusion

Rg1 at a dose of 4-800 mg/kg/d mitigates the progression of liver injury to fibrosis via anti-inflammatory, antioxidative, and anti-apoptotic pathways.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD 42024557878.

Therapeutic Actions of Hepatocyte Extracellular Vesicles in a Murine Model of Diet-Induced Steatohepatitis with Fibrosis

INTRODUCTION

Metabolic dysfunction-associated steatohepatitis (MASH) is a leading cause of liver failure globally and is characterized by hepatic steatosis and inflammation, which may progress to fibrosis, the severity of which is highly predictive of patient demise and death. In view of the lack of treatment options for MASH, we investigated the therapeutic properties of extracellular vesicles (EVs) from normal human hepatocytes, which we have previously been shown to alleviate toxin-mediated hepatic fibrosis in mice.

METHODS

C57BI/6J mice were fed a choline-deficient amino acid-defined high (60%) fat (CDAA-HF) diet for up to 12 weeks while receiving i.p. administration of EVs purified from cultured human HepG2 hepatocytes.

RESULTS

CDAA-HF diet consumption resulted in severe hepatic steatosis, increased frequency of CD45+ lymphocytes and F4/80+ macrophages, robust production of aortic smooth muscle actin (ACTA2), and deposition of interstitial collagen, as well as altered serum levels of ALT, AST, cholesterol, triglycerides, alkaline phosphatase, unconjugated bilirubin, and total protein, thus recapitulating typical MASH phenotypes. EVs administered preventively or therapeutically resulted in the restoration of serum marker levels, reduced hepatic inflammation and attenuation of collagen deposition, ACTA2 production, and expression of fibrosis-associated genes. HepG2 EVs contained 205 miRs and, among the 30 most abundant miRs, seven (miRs-423-5p, -483-5p, -191-5p, -148a-3p, -423-3p, -92a-3p, -122-5p) are predicted to directly target fibrosis-related genes (collagens, ACTA2, MMPs, and TIMPs).

CONCLUSIONS

Hepatocyte EVs are therapeutic in a mouse model of diet-induced steatohepatitis with fibrosis. Further studies of hepatocyte EVs or their cargo components as novel therapeutics for MASH in humans are warranted, including treatment of fibrotic stages, which are associated with clinical demise and are predictive of patient death.

NLRP6 overexpression improves nonalcoholic fatty liver disease by promoting lipid oxidation and decomposition in hepatocytes through the AMPK/CPT1A/PGC1A pathway

OBJECTIVES

To investigate the regulatory role of nucleotide-bound oligomerized domain-like receptor containing pyrin-domain protein 6 (NLRP6) in liver lipid metabolism and non-alcoholic fatty liver disease (NAFLD).

METHODS

Mouse models with high-fat diet (HFD) feeding for 16 weeks (n=6) or with methionine choline-deficient diet (MCD) feeding for 8 weeks (n=6) were examined for the development of NAFLD using HE and oil red O staining, and hepatic expressions of NLRP6 were detected with RT-qPCR, Western blotting, and immunohistochemical staining. Cultured human hepatocytes (LO2 cells) with adenovirus-mediated NLRP6 overexpression or knock-down were treated with palmitic acid (PA) in the presence or absence of compound C (an AMPK inhibitor), and the changes in cellular lipid metabolism were examined by measuring triglyceride, ATP and β-hydroxybutyrate levels and using oil red staining, RT-qPCR, and Western blotting.

RESULTS

HFD and MCD feeding both resulted in the development of NAFLD in mice, which showed significantly decreased NLRP6 expression in the liver. In PA-treated LO2 cells, NLRP6 overexpression significantly decreased cellular TG content and lipid deposition, while NLRP6 knockdown caused the opposite effects. NLRP6 overexpression in PA-treated LO2 cells also increased mRNA and protein expressions of PGC1A and CPT1A, levels of ATP and β-hydroxybutyrate, and the phosphorylation level of AMPK pathway; the oxidative decomposition of lipids induced by Ad-NLRP6 was inhibited by the use of AMPK inhibitors.

CONCLUSIONS

NLRP6 overexpression promotes lipid oxidation and decomposition through AMPK/CPT1A/PGC1A to alleviate lipid deposition in hepatocytes.

A Golden Shield: The Protective Role of Curcumin against Liver Fibrosis

Several chronic liver injuries can result in liver fibrosis, a wound-healing response defined by an excessive buildup of diffuse extracellular matrix (ECM). Liver fibrosis may progress to liver cirrhosis, liver failure, or hepatocellular carcinoma. Many cellular routes are implicated in the fibrosis process; however, hepatic stellate cells appear to be the main cell type involved. Curcumin, a polyphenolic substance extracted from the Curcuma longa plant, has a diversity of pharmacologic impacts, including anti- inflammatory, antioxidant, antiproliferative and antiangiogenic actions. The anti-fibrotic property of curcumin is less clear, but curcumin's ability to influence inflammatory cytokines, inflammatory pathways, the expression of pro-apoptotic (up-regulated) and anti- apoptotic (down-regulated) proteins, and its ability to lower oxidative stress likely underlie its anti-fibrotic properties. In this review, we investigate and analyze the impact of curcumin on several disorders that lead to liver fibrosis, and discuss the therapeutic applications of curcumin for these disorders.

Application and research progress of magnetic resonance proton density fat fraction in metabolic dysfunction-associated steatotic liver disease: a comprehensive review

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD), formerly known as Non-Alcoholic Fatty Liver Disease (NAFLD), is a chronic liver disorder associated with disturbances in lipid metabolism. The disease is prevalent worldwide, particularly closely linked with metabolic syndromes such as obesity and diabetes. Magnetic Resonance Proton Density Fat Fraction (MRI-PDFF), serving as a non-invasive and highly quantitative imaging assessment tool, holds promising applications in the diagnosis and research of MASLD. This paper aims to comprehensively review and summarize the applications and research progress of MRI-PDFF technology in MASLD, analyze its strengths and challenges, and anticipate its future developments in clinical practice.

Lipidome profiling in advanced metabolic liver disease identifies phosphatidylserine synthase 1 as a regulator of hepatic lipoprotein metabolism

Metabolic dysfunction-associated steatohepatitis (MASH) is characterized by defective lipid metabolism, which causes disease progression. MASH is also linked to various cardiometabolic risk factors, including obesity and type 2 diabetes. The contribution of defective lipid metabolism in MASH to cardiometabolic comorbidities is incompletely understood. Using hepatic lipidome profiling in eight mouse strains that differ in MASH susceptibility and patients with MASH, we show that phosphatidylserine (PS) accumulation and preservation of PS synthase 1 (PSS1) expression is associated with resistance to MASH and hypertriglyceridemia. Mechanistically, hepatocyte-specific PSS1 overexpression remodels the hepatic and very-low-density lipoprotein (VLDL) lipidome in mice with MASH. Specifically, we show an increase in VLDL ceramide that suppresses the expression and activity of lipoprotein lipase in skeletal muscle, thereby reducing VLDL-triglyceride clearance, fatty acid uptake, and lipid accumulation in muscle, overall exacerbating hypertriglyceridemia. Together, the results of this study identify hepatic PSS1 as a regulator of systemic lipoprotein metabolism.

Association between bowel movement frequency, stool consistency and MAFLD and advanced fibrosis in US adults: a cross-sectional study of NHANES 2005-2010

BACKGROUND

Although previous studies have established associations between specific gut microbiota (GM) and metabolic dysfunction-associated fatty liver disease (MAFLD), research examining the relationship between functional gastrointestinal symptoms and MAFLD, including advanced fibrosis, remains limited. This study aims to investigate the association between stool consistency, bowel movement frequency (BMF), and the occurrence of MAFLD and advanced fibrosis in U.S. adults.

METHODS

This population-based study included 9,928 adults from the 2005-2010 National Health and Nutrition Examination Survey (NHANES), with a mean age of 47.19 ± 16.65 years, comprising 47.7% males and 52.3% females. Weighted logistic regression was used to assess the association between stool consistency, BMF, and MAFLD or advanced fibrosis. A linear trend was assessed by treating BMF categories as continuous variables with ordinal values. The dose-response relationship between BMF and MAFLD was analyzed using restricted cubic splines (RCS) regression. Sensitivity and subgroup analyses were performed to confirm the robustness of the findings.

RESULTS

In the RCS regression, no significant nonlinear relationship was observed between BMF and the risk of MAFLD (p-overall < 0.0001; p-nonlinear = 0.0663). The multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for MAFLD were 0.82 (95% CI 0.69-0.98), 1.31 (95% CI 1.16-1.46), and 1.50 (95% CI 1.14-1.99) for participants with 3-6 BMs/week, 1-2 BMs/day, and > 2 BMs/day, respectively, compared to those with once/day (p-trend < 0.001). For stool consistency, hard stools were associated with a decreased risk of MAFLD (OR 0.77; 95% CI 0.62-0.95), whereas loose stools increased the risk (OR 1.37; 95% CI 1.05-1.80), relative to normal stools. A significant interaction between BMF and age was observed. No significant associations were found between stool consistency or BMF and advanced liver fibrosis. Sensitivity analyses confirmed the robustness of these findings.

CONCLUSIONS

This cross-sectional study demonstrates that a BMF of 3-6 BMs/week and hard stools are associated with a reduced risk of MAFLD, whereas a BMF of more than once/day and loose stools are linked to an increased risk of MAFLD. Moreover, no significant associations were observed between stool consistency, BMF, and advanced fibrosis among individuals diagnosed with MAFLD.

CLINICAL TRIAL NUMBER

Not applicable.

Vitamin D 1,25-Dihydroxyvitamin D3 reduces lipid accumulation in hepatocytes by inhibiting M1 macrophage polarization

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), which is a significant liver condition associated with metabolic syndrome, is the leading cause of liver diseases globally and its prevalence is on the rise in most nations. The protective impact of vitamin D on NAFLD and its specific mechanism remains unclear.

AIM

To examine the role of vitamin D in NAFLD and how vitamin D affects the polarization of hepatic macrophages in NAFLD through the vitamin D receptor (VDR)-peroxisome proliferator activated receptor (PPAR)γ pathway.

METHODS

Wild-type C57BL/6 mice were provided with a high-fat diet to trigger NAFLD model and administered 1,25-dihydroxy-vitamin D [1,25(OH)2D3] supplementation. 1,25(OH)2D3 was given to RAW264.7 macrophages that had been treated with lipid, and a co-culture with AML12 hepatocytes was set up. Lipid accumulation, lipid metabolism enzymes, M1/M2 phenotype markers, proinflammatory cytokines and VDR-PPARγ pathway were determined.

RESULTS

Supplementation with 1,25(OH)2D3 relieved hepatic steatosis and decreased the proinflammatory M1 polarization of hepatic macrophages in NAFLD. Administration of 1,25(OH)2D3 suppressed the proinflammatory M1 polarization of macrophages induced by fatty acids, thereby directly relieving lipid accumulation and metabolism in hepatocytes. The VDR-PPARγ pathway had a notable impact on reversing lipid-induced proinflammatory M1 polarization of macrophages regulated by the administration of 1,25(OH)2D3.

CONCLUSION

Supplementation with 1,25(OH)2D3 improved hepatic steatosis and lipid metabolism in NAFLD, linked to its capacity to reverse the proinflammatory M1 polarization of hepatic macrophages, partially by regulating the VDR-PPARγ pathway. The involvement of 1,25(OH)2D3 in inhibiting fatty-acid-induced proinflammatory M1 polarization of macrophages played a direct role in relieving lipid accumulation and metabolism in hepatocytes.

Determining the sensitivity and specificity of the calculated fatty liver index in comparison with ultrasound

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease in human history and it is expected to surpass other causes of liver disease mortality by 2030. Therefore, finding an alternative way to diagnose steatosis in the early stage when imaging modalities are not available is crucial. This study decided to validate the optimal cut-off points and the sensitivity and specificity of the Fatty Liver Index (FLI) based on the Iranian population compared to ultrasonography.

METHODS

The data of 367 individuals, 108 males and 259 females over 35, were analyzed. Hepatic steatosis was identified by ultrasound. FLI was determined from waist circumference, gamma-glutamyl transferase, triglyceride, and body mass index data. The receiver operating characteristic curve (ROC) was used to determine the best FLI index cut point for diagnosing nonalcoholic fatty liver. The sensitivity and specificity indices were calculated for the determined cut point.

RESULTS

The AUC of the FLI index in diagnosing NAFLD in the total population was 0.733 (95% CI: 0.68-0.77, specificity = 0.6705, sensitivity = 0.7320) with the optimal COP of 40.6. There was a statistically significant association between non-alcoholic liver disease and FLI-based ultrasound (p < 0.0001). Furthermore, the sex-specific optimal COPs of FLI was 33.4, specificity = 0.6071, sensitivity = 0.8462 in men vs. 27.8, sensitivity = 0.8233, specificity = 0.7655 in women.

CONCLUSION

FLI is a reliable tool for identifying individuals with NAFLD. It has the potential to aid in detecting and managing this condition in large-scale populations while other methods are not available. We also determine an optimal COP of 40.6 with sensitivity and specificity of 73.20% and 67.05% in the general population, respectively.

Multi-omics joint analysis reveals that the Miao medicine Yindanxinnaotong formula attenuates non-alcoholic fatty liver disease

BACKGROUD

Non-alcoholic fatty liver disease (NAFLD) is a growing chronic liver disease worldwide, and no effective agent is approved yet for this condition. Traditional Chinese Medicine (TCM), which has been practiced for thousands of years in China and other Asian countries, is considered an important source for identifying novel medicines for various diseases. Miao medicine Yindanxinnaotong formula (YDX) is a classical TCM for the treatment of hyperlipidemia disease by reducing blood lipid content, while the role of YDX have not been clarified in NAFLD.

PURPOSE

To investigate the protective effect of YDX on NAFLD in mice induced by high fat diet (HFD) and clarify the potential mechanism.

METHODS

NAFLD mice model was constructed by receiving HFD for 10-week period with or without YDX administration. Lipid profiles, biochemical indicators, and histopathological staining were performed to evaluate the extent of hepatic lipid accumulation and hepatic steatosis. 16S rRNA sequencing was used to determine the gut microbial composition. Serum metabolomics was further used to investigate the changes in plasma biomarkers for NAFLD-associated by UPLC-Q-TOF/MS analysis. Subsequently, liver transcriptomics was employed to identify differentially expressed genes and explore regulatory pathways. Then, lipid metabolism-related proteins and inflammation factors were examined by Western blot and ELISA.

RESULTS

YDX reduced body weight gain, liver index and inflammatory cytokines levels, along with improved hepatic steatosis, serum lipid profile, sensitivity to insulin and also tolerance to glucose, and enhanced oxidative defense system in HFD-induced mice. Also, YDX remarkedly affected gut microbiota diversity and community richness and decreased the ratio of Firmicutes/Bacteroidetes. Meanwhile, YDX also reduced the production of harmful lipid metabolites in the sera of NAFLD mice, such as LPC(18:0), LPC(18:1) and carnitine. Notably, consistent with liver transcriptomics results, YDX downregulated the expression of proteins implicated in de novo lipid synthesis (Srebp-1c, Acaca, Fasn, Scd-1, and Cd36) and pro-inflammatory cytokines (IL-6 and TNF-α), and increased the expression of proteins-related fatty acid β-oxidation (Ampkα, Ppar-α, and Cpt-1) in the liver by activating Ampk pathway.

CONCLUSION

YDX is promisingly an effective therapy for preventing NAFLD by modulating the Ampk pathway, inhibiting gut microbiota disorder, and reducing the production of harmful lipid metabolites.

Insights into the pathogenesis of gestational and hepatic diseases: the impact of ferroptosis

Ferroptosis, a distinct form of non-apoptotic cell death characterized by iron dependency and lipid peroxidation, is increasingly linked to various pathological conditions in pregnancy and liver diseases. It plays a critical role throughout pregnancy, influencing processes such as embryogenesis, implantation, and the maintenance of gestation. A growing body of evidence indicates that disruptions in these processes can precipitate pregnancy-related disorders, including pre-eclampsia (PE), gestational diabetes mellitus (GDM), and intrahepatic cholestasis of pregnancy (ICP). Notably, while ICP is primarily associated with elevated maternal serum bile acid levels, its precise etiology remains elusive. Oxidative stress induced by bile acid accumulation is believed to be a significant factor in ICP pathogenesis. Similarly, the liver's susceptibility to oxidative damage underscores the importance of lipid metabolism dysregulation and impaired iron homeostasis in the progression of liver diseases such as alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), cholestatic liver injury, autoimmune hepatitis (AIH), acute liver injury, viral hepatitis, liver fibrosis, and hepatocellular carcinoma (HCC). This review discusses the shared signaling mechanisms of ferroptosis in gestational and hepatic diseases, and explores recent advances in understanding the mechanisms of ferroptosis and its potential role in the pathogenesis of gestational and hepatic disorders, with the aim of identifying viable therapeutic targets.

Elevated serum growth differentiation factor 15 and decorin predict the fibrotic progression of metabolic dysfunction-associated steatotic liver disease

Mitochondrial dysfunction with oxidative stress contributes to metabolic dysfunction-associated steatotic liver disease (MASLD) progression. We aimed to evaluate the fibrosis predictive efficacy of a novel non-invasive diagnostic panel using metabolic stress biomarkers. From a population-based general cohort, 144 subjects with MASLD were recruited in the development group and underwent magnetic resonance imaging-based liver examinations, anthropometric and laboratory tests. As an external validation group, 41 patients enrolled in a biopsy-evaluated MASLD cohort participated in this study. Liver fat content and stiffness were measured by magnetic resonance (MR) imaging-proton density fat fraction and MR elastography (MRE), respectively. Serologic stress biomarkers were quantitated by ELISA. Multivariate regression showed that waist-to-height ratio, growth differentiation factor-15 (GDF15), γ-glutamyltransferase, decorin, and alkaline-phosphatase were independent predictors of hepatic fibrosis (rank-ordered by Wald). The area under receiver-operator characteristics curve [AUROC (95% CI)) of the metabolic stress index for fibrosis (MSI-F) was 0.912 (0.85‒0.98) and 0.977 (0.92‒1.00) in development and validation groups, respectively. MSI-F also had better diagnostic accuracy (82.6‒92.4%) than other fibrosis indices in the both study cohorts. MSI-F consistently differentiated fibrosis severities across cohorts of MRE-evaluated general population and biopsy-proven patients with MASLD, while other indices showed no or less discrimination. MSI-F, as a novel non-invasive index based on a stress-stimulated protective hormone GDF15 and decorin, effectively predicted hepatic fibrosis. Furthermore, MSI-F may serve as pre-screening tool to increase the population that could be excluded from further evaluation, reducing unnecessary invasive investigations more effectively than other indices.

Ethnic Minority Disparities in the Epidemiology of Metabolic Dysfunction-Associated Steatotic Liver Disease in a Representative Area of China

OBJECTIVE

We aimed to evaluate the differences in clinical features and lifestyle between Han and ethnic minority populations in Guangdong Province, China and their impacts on the ever-growing burden of metabolic dysfunction-associated steatotic liver disease (MASLD).

METHODS

In this cross-sectional investigation in Guangdong Province, China, one of the most densely populated areas with imbalanced development, multistage stratified random sampling was used. Demographic, socioeconomic, and lifestyle data of participants were collected. Assessment of hepatic steatosis and liver stiffness measurement were performed.

RESULTS

A total of 7287 individuals were recruited, including 7076 Han and 211 ethnic minority individuals, with similar MASLD prevalence between the two groups (35.8% vs 34.6%, p = 0.771). More ethnic minority individuals presented advanced fibrosis (≥ F3) overall and in subgroups of overweight/obesity, lean/normal weight, and males, but less advanced fibrosis in females and age of 30-34 years (all p < 0.05) than the Han Chinese. Proper physical activity was associated with a reduced risk of MASLD (Han: odds ratio [OR] 0.64, p = 0.021; ethnic minority: OR 0.06, p = 0.017). Sufficient sleep, drinking tea, and dietary fiber intake were protective factors for MASLD, while long sedentary duration, midnight snacks, dining out, and excessive intake of salt, red meat, and sugar were associated with a higher risk of MASLD in Han Chinese only.

CONCLUSIONS

There was a strikingly high burden of MASLD in the ethnic minority in Guangdong Province, China, and their lifestyle differences compared with Han Chinese may contribute to the epidemic surge of MASLD.

Silica nanoparticles induce liver lipid metabolism disorder via ACSL4-mediated ferroptosis

The disease burden of non-alcoholic fatty liver disease (NAFLD) is increasing worldwide. Emerging evidence has revealed that silica nanoparticles (SiNPs) could disorder the liver lipid metabolism and cause hepatotoxicity, but the underlying mechanism remains unknown. The purpose of this study is to elucidate the molecular mechanism of hepatic lipid metabolism disorder caused by SiNPs, and to reveal the role of ferroptosis in SiNPs-induced hepatotoxicity. To explore the phenotypic changes in liver, the wild-type C57BL/6J mice were exposed to different doses of SiNPs (5, 10, 20 mg/kg·bw) with or without melatonin (20 mg/kg·bw). SiNPs accelerated hepatic oxidative stress and promoted pathological injury and lipid accumulation, resulting in NAFLD development. Melatonin significantly inhibited the oxidative damage caused by SiNPs. Then, the hepatocytes were treated with SiNPs, the ferroptosis inducer and inhibitor, respectively. In vitro, SiNPs (25 μg/mL) generated mitochondrial and intracellular Fe2+ accumulation and lipid peroxidation repair ability impairment, decreased the activity of GPX4 through ACSL4/p38 MAPK signaling pathway, resulting in ferroptosis of hepatocytes. Notably, Erastin (the ferroptosis activator, 5 μM) increased the sensitivity of hepatocytes to ferroptosis. Ferrostatin-1 (Fer-1, the ferroptosis inhibitor, 5 μM) restored GPX4 activity and protected against deterioration of lipid hydroperoxides (LOOHs) to salvage SiNPs-induced cytotoxicity. Finally, the liver tissue conditional ACSL4 knockout (cKO) mice and ACSL4-KO hepatocytes were adopted to further identify the role of the ACSL4-mediated ferroptosis on SiNPs-induced NAFLD development. The results displayed ACSL4 knockout could down-regulate the lipid peroxidation and ferroptosis, ultimately rescuing the progression of NAFLD. In summary, our data indicated that ACSL4/p38 MAPK/GPX4-mediated ferroptosis was a novel and critical mechanism of SiNPs-induced NAFLD.

Transcriptomic and Metabolomic Analyses Reveal the Attenuating Role of Cordycepin and Cordyceps militaris Extract on Acute Liver Injury Induced by LPS in Piglets

Cordyceps militaris extract (CME) contains many bioactive compounds, mainly cordycepin (CPN). This study aimed to investigate the possible mechanisms underlying the amelioration of LPS-induced acute liver injury in piglets by CME or CPN supplementation using multi-omics analysis. Twenty-four weaned piglets were randomly distributed into 4 groups (n = 6): the control and LPS groups were fed basal diets; the CPN + LPS (CPN-LPS) and CME + LPS (CME-LPS) groups were fed the basal diets supplemented with CME or CPN. The results showed that CPN or CME supplementation significantly decreased the C-reactive protein level (p < 0.05) and improved liver tissue pathology to prevent acute liver injury after LPS treatment. Compared with LPS, the transcriptomic analysis indicated that CPN supplementation significantly downregulated cell adhesion molecules, while CME supplementation significantly downregulated inflammatory mediator regulation of TRP channels, complement and coagulation cascades and cytokine-cytokine receptor interaction. The metabolomic results showed that CPN or CME supplementation significantly reduced disease biomarker of bicyclo-prostaglandin E2, and increased levels of deoxyinosine and 3-hydroxyanthranilic acid (p < 0.05). The combined transcriptome and metabolome helped identify two metabolites PC 34:2 and PC 36:0, which may be associated with the restoration of liver cell morphology. In conclusion, CPN and CME could attenuate LPS-induced acute liver injury by regulating immune-related genes and metabolites. This study elucidates the potential protective mechanism of CPN or CME supplementation against acute liver injury.

Liver fibrosis pathologies and potentials of RNA based therapeutics modalities

Liver fibrosis (LF) occurs when the liver tissue responds to injury or inflammation by producing excessive amounts of scar tissue, known as the extracellular matrix. This buildup stiffens the liver tissue, hinders blood flow, and ultimately impairs liver function. Various factors can trigger this process, including bloodborne pathogens, genetic predisposition, alcohol abuse, non-steroidal anti-inflammatory drugs, non-alcoholic steatohepatitis, and non-alcoholic fatty liver disease. While some existing small-molecule therapies offer limited benefits, there is a pressing need for more effective treatments that can truly cure LF. RNA therapeutics have emerged as a promising approach, as they can potentially downregulate cytokine levels in cells responsible for liver fibrosis. Researchers are actively exploring various RNA-based therapeutics, such as mRNA, siRNA, miRNA, lncRNA, and oligonucleotides, to assess their efficacy in animal models. Furthermore, targeted drug delivery systems hold immense potential in this field. By utilizing lipid nanoparticles, exosomes, nanocomplexes, micelles, and polymeric nanoparticles, researchers aim to deliver therapeutic agents directly to specific biomarkers or cytokines within the fibrotic liver, increasing their effectiveness and reducing side effects. In conclusion, this review highlights the complex nature of liver fibrosis, its underlying causes, and the promising potential of RNA-based therapeutics and targeted delivery systems. Continued research in these areas could lead to the development of more effective and personalized treatment options for LF patients.

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.

L-Theanine Ameliorates Obesity-Related Complications Induced by High-Fat Diet in Mice: Insights from Transcriptomics and Metabolomics

Obesity is a major public health concern globally. Plant-based ingredients have been proposed as alternative treatments for obesity. L-Theanine (THE), a unique nutraceutical component of tea, is known for its neuroprotective and cognitive benefits. However, there are few reports on THE's effects and mechanisms in improving obesity and its complications. In this study, the alleviating effects and potential mechanisms of THE on obesity-related complications (ORCs) induced by a high-fat diet(HFD) in mice were explored by performing biochemical, hepatic transcriptomics, and plasma metabolomics analyses. The results indicated THE (900 mg/kg of body weight) was effective in mitigating ORCs by decreasing body weight gain and fat deposition, improving glycolipid metabolism disorders, inflammation dysregulation, and alleviating fatty liver formation due to long-term HFD. The hepatic transcriptomics data suggested that THE intervention suppresses the lipid metabolism and inflammation pathways in HFD-fed mice, thereby inhibiting hepatic steatosis and inflammation. Moreover, plasma metabolomics analysis revealed that THE exhibited positive effects on the homeostasis of plasma metabolite balance, such as phosphatidylcholine (PC(14:0/18:1)), phosphatidylethanolamine (Lyso-PE(14:0)), phosphatidic acid (PA(16:0e/18:0)), stigmasterol, and deoxycholic acid glycine conjugate. These metabolites were strongly correlated with ORC-related indicators. Our results indicated that THE, as a functional food additive, possesses potential for ORC alleviation. However, the exact molecular mechanism of how THE alleviates ORCs needs to be investigated in the future.

Transcriptome analysis reveals hepatic disordered lipid metabolism, lipotoxic injury, and abnormal development in IUGR sheep fetuses due to maternal undernutrition during late pregnancy

Although lipid metabolism in fetal livers under intrauterine growth restriction (IUGR) conditions has been widely studied, the implications of maternal undernutrition on fetal hepatic lipid metabolism, lipotoxic injury, and abnormal development remain largely unknown. Therefore, this study investigated the effects of maternal undernutrition on disordered hepatic lipid metabolism, lipotoxic injury, and abnormal development in IUGR sheep fetuses using transcriptome analysis. Seventeen singleton ewes were randomly divided into three groups on day 90 of pregnancy: a control group (CG; 0.63 MJ metabolic energy/body weight (ME/BW)0.75/day, n = 5), maternal undernutrition group 1 (MU1; 0.33 MJ ME/BW0.75/day, n = 6), and maternal undernutrition group 2 (MU2; 0.20 MJ ME/BW0.75/day, n = 6). The fetuses were euthanized and recovered on day 130 of pregnancy. The levels of free fatty acids (FFA) in maternal blood (P < 0.01), fetal blood (P < 0.01), and fetal livers (P < 0.05) were increased in the MU1 and MU2 groups, but fetal hepatic triglyceride (TG) levels in the MU2 group (P < 0.01) and β-hydroxybutyrate levels in the MU1 and MU2 groups (P < 0.01) were decreased compared to the CG. Severe inflammatory cell infiltration and increased non-alcoholic fatty liver disease activity scores were observed in MU1 and MU2 fetuses (P < 0.01). Progressive deposition of fetal hepatic reticular fibers and collagen fibers in the fetal livers of the MU1 and MU2 groups and significant hepatic fibrosis were observed in the MU2 fetuses (P < 0.05). Gene set enrichment analysis showed that genes involved in lipid accumulation and FFA beta oxidation were downregulated in both MU groups compared to those in the controls. The fetal liver mRNA expression of the β-oxidation regulator, acetyl-CoA acetyltransferase 1, and the TCA regulator, isocitrate dehydrogenase were reduced in MU1 (P < 0.05) and MU2 (P < 0.01) fetuses, and downregulated mRNA expression of long chain fatty acid CoA ligase 1 (P < 0.05) and glycerol-3-phosphate acyltransferase (P < 0.01) was observed in MU2 fetuses. Differentially expressed genes (DEGs) in MU1 versus CG (360 DEGs) and MU2 versus CG (746 DEGs) were identified using RNA sequencing. Bioinformatics analyses of the 231 intersecting DEGs between MU1 versus CG and MU2 versus CG indicated that neutrophil extracellular traps (NETs) were induced and played a central role in fetal hepatic injury in IUGR sheep. Increased maternal blood myeloperoxidase (MPO) levels (P < 0.01), NE (Elane)-positive areas in fetal liver sections (P < 0.05), and fetal liver MPO protein expression (P < 0.01) were found in the MU1 and MU2 groups; however, MPO levels were reduced in the fetal membrane (P < 0.01) and fetal blood (P < 0.05) in the MU1 group, and in the maternal-fetal placenta and fetal blood in the MU2 group (P < 0.01). Analysis of gene expression trends in the intersecting DEGs between MU1 versus CG (129 DEGs) and MU2 versus CG (515 DEGs) further revealed that 30 hub genes were essential regulators of the G2/M cell cycle, all of which were associated with hepatocellular carcinoma. G0/G1 phase cells of the fetal liver were reduced in the MU1 (P < 0.05) and MU2 (P < 0.01) groups, whereas G2/M phase cells were elevated in the MU1 and MU2 groups (P < 0.01). The representatives of upregulated hub genes and fetal liver protein expression of maternal embryonic leucine zipper kinase and protein regulator of cytokinesis 1 were progressively enhanced in the MU1 and MU2 groups (P < 0.01), and topoisomerase II alpha protein expression in the MU2 group (P < 0.05), as expected. These results indicate that FFA overload, severe lipotoxic injury, and NETs were induced, and disease-promoting regulators of the G2/M cell cycle were upregulated in the fetal liver of IUGR sheep. These findings provide new insights into the pathogenesis of impaired hepatic lipid metabolism and abnormal development and the molecular origin of post-natal liver disease in IUGR due to maternal undernutrition. This information can support the development of new therapeutic strategies.

Evaluating the therapeutic potential of genetically engineered probiotic Zbiotics (ZB183) for non-alcoholic steatohepatitis (NASH) management via modulation of the cGAS-STING pathway

NAFLD/NASH has emerged as a global health concern with no FDA-approved treatment, necessitating the exploration of novel therapeutic elements for NASH. Probiotics are known as an important adjunct therapy in NASH. Zbiotics (ZB183) is the first commercially available genetically engineered probiotic. Herein, we aimed to evaluate the potential therapeutic effects of Zbiotics administration on NASH management by modulating the cGAS-STING-signaling pathway-related RNA network. In silico data analysis was performed and three DEGs (MAPK3/EDN1/TNF) were selected with their epigenetic modulators (miR-6888-5p miRNA, and lncRNA RABGAP1L-DT-206). The experimental design included NASH induction with an HSHF diet in Wistar rats and Zbiotics administration in NASH rats in comparison to statin treatment. Liver functions and lipid profile were assessed. Additionally, the expression levels of the constructed molecular network were assessed using RT-PCR. Moreover, the Zbiotics effects in NASH were further validated with histopathological examination of liver and colon samples. Also, immunohistochemistry staining of hepatic TNF-α and colonic occludin was assessed. Oral administration of Zbiotics for four weeks downregulated the expression of the cGAS-STING-related network (MAPK3/EDN1/TNF/miR-6888-5p miRNA/lncRNA RABGAP1L-DT-206) in NASH models. Zbiotics also ameliorated hepatic inflammation and steatosis, as evidenced by a notable improvement in NAS score and decreased hepatic TNF-α levels. Furthermore, Zbiotics exhibited favorable effects on colon health, including increased crypt length, reduced inflammatory cell infiltration, and restoration of colonic mucosa occludin expression. In conclusion, our findings suggest that Zbiotics has potential therapeutic effects on NASH via modulating the gut-liver axis and the cGAS-STING signaling pathway.

Intestinal NSD2 Aggravates Nonalcoholic Steatohepatitis Through Histone Modifications

Mounting clinical evidence suggests that a comprised intestinal barrier contributes to the progression of nonalcoholic steatohepatitis (NASH); nevertheless, the precise mechanism remains elusive. This study unveils a significant upregulation of nuclear receptor-binding SET domain protein 2 (NSD2) in the intestines of obese humans and mice subjected to a high-fat cholesterol diet (HFCD). Intestine-specific NSD2 knockout attenuated the progression of intestinal barrier impairment and NASH, whereas NSD2 overexpression exacerbated this progression. Mechanistically, NSD2 directly regulates the transcriptional activation of Ern1 by demethylating histone H3 at lysine 36 (H3K36me2), thus activating the ERN1-JNK axis to intensify intestinal barrier impairment and subsequently foster NASH progression. These findings elucidate the crucial role of NSD2-mediated H3K36me2 in intestinal barrier impairment, suggesting that targeting intestinal NSD2 can represent a novel therapeutic approach for NASH.

Haloacetamides disinfection by-products, a potential risk factor for nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder characterized by abnormal lipid deposition, with oxidative stress being a risk factor in its onset and progression. Haloacetamides (HAcAms), as unregulated disinfection by-products in drinking water, may alter the incidence and severity of NAFLD through the production of oxidative stress. We explored whether HAcAms at 1, 10, and 100-fold concentrations in Shanghai drinking water perturbed lipid metabolism in normal human liver LO-2 cells. CRISPR/Cas9 was used to construct a LO-2 line with stable NRF2 knock-down (NRF2-KD) to investigate the mechanism underlying abnormal lipid accumulation and hepatocyte damage caused by mixed exposure to HAcAms. At 100-fold real-world concentration, HAcAms caused lipid deposition and increased triglyceride accumulation in LO-2 cells, consistent with altered de novo lipogenesis. Differences in responses to HAcAms in normal and NRF2-KD LO-2 cells indicated that HAcAms caused hepatocyte lipid deposition and triglyceride accumulation by activation of the NRF2/PPARγ pathway and aggravated liver cell toxicity by inducing ferroptosis. These results indicate that HAcAms are important risk factors for NAFLD. Further observations and verifications of the effect of HAcAms on NAFLD in the population are warranted in the future.

Hepatocellular carcinoma and lipid metabolism: Novel targets and therapeutic strategies

Hepatocellular carcinoma (HCC) is an increasingly prevalent disease that is associated with high and continually rising mortality rates. Lipid metabolism holds a crucial role in the pathogenesis of HCC, in which abnormalities pertaining to the delicate balance of lipid synthesis, breakdown, and storage, predispose for the pathogenesis of the nonalcoholic fatty liver disease (NAFLD), a disease precursor to HCC. If caught early enough, HCC treatment may be curative. In later stages, treatment is only halting the inevitable outcome of death, boldly prompting for novel drug discovery to provide a fighting chance for this patient population. In this review, we begin by providing a summary of current local and systemic treatments against HCC. From such we discuss hepatic lipid metabolism and highlight novel targets that are ripe for anti-cancer drug discovery. Lastly, we provide a targeted summary of current known risk factors for HCC pathogenesis, providing key insights that will be essential for rationalizing future development of anti-HCC therapeutics.

Genetically engineered long-acting Esculentin-2CHa(1-30) fusion protein with potential applicability for the treatment of NAFLD

Esculentin-2CHa(1-30) (‟ESC") has been reported as a potent anti-diabetic peptide with little toxicity. However, its very short plasma residence time severely limits the therapeutic efficacy. To address this issue, we genetically engineered a fusion protein of tandem trimeric ESC with an albumin binding domain (ABD) and a fusion partner, SUMO (named ‟SUMO-3×ESC-ABD"). The SUMO-3×ESC-ABD, successfully produced from E. coli, showed low cellular and hemolytic toxicity while displaying potent activities for the amelioration of hyperglycemia as well as non-alcoholic fatty liver disease (NAFLD) in vitro. In animal studies, the estimated plasma half-life of SUMO-3×ESC-ABD was markedly longer (427-fold) than that of the ESC peptide. In virtue of the extended plasma residence, the SUMO-3×ESC-ABD could produce significant anti-hyperglycemic effects that lasted for >2 days, while both the ESC or ESC-ABD peptides elicited little effects. Further, twice-weekly treatment for 10 weeks, the SUMO-3×ESC-ABD displayed significant improvement in blood glucose control with a reduction in body weight. Most importantly, a significant improvement in the conditions of NAFLD was observed in the SUMO-3×ESC-ABD-treated mice. Along the systemic effects (by improved glucose tolerance and body weight reduction), direct inhibition of the hepatocyte lipid uptake was suggested as the major mechanism of the anti-NAFLD effects. Overall, this study demonstrated the utility of the long-acting SUMO-3×ESC-ABD as a potent drug candidate for the treatment of NAFLD.

Systemic impacts of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) on heart, muscle, and kidney related diseases

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is the most common liver disorder worldwide, with an estimated global prevalence of more than 31%. Metabolic dysfunction-associated steatohepatitis (MASH), formerly known as non-alcoholic steatohepatitis (NASH), is a progressive form of MASLD characterized by hepatic steatosis, inflammation, and fibrosis. This review aims to provide a comprehensive analysis of the extrahepatic manifestations of MASH, focusing on chronic diseases related to the cardiovascular, muscular, and renal systems. A systematic review of published studies and literature was conducted to summarize the findings related to the systemic impacts of MASLD and MASH. The review focused on the association of MASLD and MASH with metabolic comorbidities, cardiovascular mortality, sarcopenia, and chronic kidney disease. Mechanistic insights into the concept of lipotoxic inflammatory "spill over" from the MASH-affected liver were also explored. MASLD and MASH are highly associated (50%-80%) with other metabolic comorbidities such as impaired insulin response, type 2 diabetes, dyslipidemia, hypertriglyceridemia, and hypertension. Furthermore, more than 90% of obese patients with type 2 diabetes have MASH. Data suggest that in middle-aged individuals (especially those aged 45-54), MASLD is an independent risk factor for cardiovascular mortality, sarcopenia, and chronic kidney disease. The concept of lipotoxic inflammatory "spill over" from the MASH-affected liver plays a crucial role in mediating the systemic pathological effects observed. Understanding the multifaceted impact of MASH on the heart, muscle, and kidney is crucial for early detection and risk stratification. This knowledge is also timely for implementing comprehensive disease management strategies addressing multi-organ involvement in MASH pathogenesis.

Role of Nonalcoholic Fatty Liver Disease in Periodontitis: A Bidirectional Relationship

Nonalcoholic fatty liver disease (NAFLD) and periodontitis share common risk factors such as obesity, insulin resistance (IR), and dyslipidemia, which contribute to systemic inflammation. It has been suggested that a bidirectional relationship exists between NAFLD and periodontitis, indicating that one condition may exacerbate the other. NAFLD is characterized by excessive fat deposition in the liver and is associated with low-grade chronic inflammation. There are several risk factors for the development of NAFLD, including gender, geriatric community, race, ethnicity, poor sleep quality and sleep deprivation, physical activity, nutritional status, dysbiosis gut microbiota, increased oxidative stress, overweight, obesity, higher body mass index (BMI), IR, type 2 diabetes mellitus (T2DM), metabolic syndrome (MetS), dyslipidemia (hypercholesterolemia), and sarcopenia (decreased skeletal muscle mass). This systemic inflammation can contribute to the progression of periodontitis by impairing immune responses and exacerbating the inflammatory processes in the periodontal tissues. Furthermore, individuals with NAFLD often exhibit altered lipid metabolism, which may affect oral microbiota composition, leading to dysbiosis and increased susceptibility to periodontal disease. Conversely, periodontitis has been linked to the progression of NAFLD through mechanisms involving systemic inflammation and oxidative stress. Chronic periodontal inflammation can release pro-inflammatory cytokines and bacterial toxins into the bloodstream, contributing to liver inflammation and exacerbating hepatic steatosis. Moreover, periodontitis-induced oxidative stress may promote hepatic lipid accumulation and IR, further aggravating NAFLD. The interplay between NAFLD and periodontitis underscores the importance of comprehensive management strategies targeting both conditions. Lifestyle modifications such as regular exercise, a healthy diet, and proper oral hygiene practices are crucial for preventing and managing these interconnected diseases. Additionally, interdisciplinary collaboration between hepatologists and periodontists is essential for optimizing patient care and improving outcomes in individuals with NAFLD and periodontitis.

O-GlcNAcylation promotes the progression of nonalcoholic fatty liver disease by upregulating the expression and function of CD36

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) and its progressive variant, nonalcoholic steatohepatitis (NASH), constitute a burgeoning worldwide epidemic with no FDA-approved pharmacotherapies. The multifunctional immunometabolic receptor, fatty acid translocase CD36 (CD36), plays an important role in the progression of hepatic steatosis. O-GlcNAcylation is a crucial posttranslational modification that mediates the distribution and function of CD36, but its involvement in NAFLD remains poorly understood.

METHODS

O-GlcNAcylation and CD36 expression were evaluated in human liver tissues obtained from NASH patients and normal control. Mice with hepatocyte-specific CD36 knockout were administered adeno-associated viral vectors expressing wild-type CD36 (WT-CD36) or CD36 O-GlcNAcylation site mutants (S468A&T470A-CD36) and were provided with a high-fat/high-cholesterol (HFHC) diet for 3 months. RT-qPCR analysis, immunoblotting, dual-luciferase reporter assays, chromatin immunoprecipitation, and coimmunoprecipitation were performed to explore the mechanisms by which O-GlcNAcylation regulates CD36 expression. Membrane protein extraction, immunofluorescence analysis, site-directed mutagenesis, and fatty acid uptake assays were conducted to elucidate the impact of O-GlcNAcylation on CD36 function.

RESULTS

O-GlcNAcylation and CD36 expression were significantly increased in patients with NASH, mouse models of NASH, and palmitic acid-stimulated hepatocytes. Mechanistically, the increase in O-GlcNAcylation facilitated the transcription of CD36 via the NF-κB signalling pathway and stabilized the CD36 protein by inhibiting its ubiquitination, thereby promoting CD36 expression. On the other hand, O-GlcNAcylation facilitated the membrane localization of CD36, fatty acid uptake, and lipid accumulation. However, site-directed mutagenesis of residues S468 and T470 of CD36 reversed these effects. Furthermore, compared with their WT-CD36 counterparts, HFHC-fed S468A&T470A-CD36 mice exhibited decreases in systemic insulin resistance, steatosis severity, inflammation and fibrosis. Pharmacological inhibition of O-GlcNAcylation and CD36 also mitigated the progression of NASH.

CONCLUSIONS

O-GlcNAcylation promotes the progression of NAFLD by upregulating CD36 expression and function. Inhibition of CD36 O-GlcNAcylation protects against NASH, highlighting a potentially effective therapeutic approach for individuals with NASH.