Metabolic-associated fatty liver disease and lipoprotein metabolism

Quercetin alleviates metabolic-associated fatty liver disease by tuning hepatic lipid metabolism, oxidative stress and inflammation

The natural flavonoid quercetin, which exhibits a range of biological activities, has been implicated in liver disease resistance in recent research. In vivo study attesting to quercetin's protective effect against metabolic-associated fatty liver disease (MAFLD) is inadequate, however. Here, our investigation explored the potential benefits of quercetin in preventing MAFLD in C57BL/6 mice fed a high-fat diet (HFD). The results revealed that quercetin ameliorated the aberrant enhancement of body and liver weight. The hepatic histological anomalie induced by MAFLD were also mitigated by quercetin. HFD-induced imbalance in serum LDL, HDL, AST, ALT, TG, and LDH was mitigated by quercetin. Mechanically, we found that quercetin improved lipid metabolism by reducing lipogenesis proteins including ACC, FASN, and SREBP-1c and enhancing β-oxidation proteins including PPARα and CPT1A. In vitro study demonstrated that quercetin regulated hepatic lipid metabolism by targeting SREBP-1c and PPARα. Additionally, quercetin enhanced the antioxidant capacity in HFD-treated mice by downregulating Nrf2 and HO-1 expressions and upregulating SOD and GPX1 expressions. The hyper-activation of inflammation was also restored by quercetin via eliminating the phosphorylation of IκBα and NF-κB p65. Collectively, our observations highlight that quercetin exerts hepatoprotective properties in MAFLD mice by regulating hepatic lipid metabolism, oxidative stress and inflammatory response.

GSK621 ameliorates lipid accumulation via AMPK pathways and reduces oxidative stress in hepatocytes in vitro and in obese mice in vivo

INTRODUCTION

Metabolic-dysfunction-associated fatty liver disease (MAFLD) represents a broad spectrum of liver lipid metabolism disorders associated with metabolic homeostasis, inflammation, oxidative stress, and fibrogenesis. The incidence of MAFLD has increased in recent years, but there is a lack of effective treatment strategies. GSK621 shows potential as a novel adenosine-monophosphate-activated protein kinase (AMPK) agonist; however, its function in lipid metabolism has not yet been confirmed.

OBJECTIVES

This study aimed to determine the effects of GSK621 on liver lipid accumulation in vitro and vivo and explore the underlying mechanism of these effects.

METHODS

The function of GSK621 in lipid deposition was investigated in vitro with HepG2 cells and normal mouse liver cells (AML12), and in vivo using C57BL/6 J mice fed with a high-fat diet (60 % fat) for 8 weeks to establish a model of MAFLD, followed by GSK621 treatment for a further 8 weeks.

RESULTS

GSK621 treatment significantly improved hepatocyte steatosis via the AMPK-carnitine palmitoyl transferase 1 (CPT1A) pathway and decreased levels of reactive oxygen species (ROS) in cells, accompanied by elevated expression of antioxidative stress proteins. MAFLD mice showed significant improvements in liver steatosis after GSK621 treatment, as well as increased expression of liver proteins related to the AMPK pathway and antioxidative stress.

CONCLUSION

GSK621 can improve hepatocytes steatosis in vitro and vivo via the AMPK-CPT1A pathway by increasing lipid metabolism and augmenting expression of antioxidant-stress-related proteins to reduce ROS deposition.

Protein kinase-mediated inhibition of autophagy by palmitic acid in hepatocytes

Steatosis is characterized by an increase in free fatty acids, such as palmitic acid (PA), in hepatocytes and the accumulation of triglycerides in the liver. However, the role of intracellular autophagy in PA accumulation-induced hepatotoxicity is not clearly understood. Therefore, in this study, we investigated the effects of PA on autophagy in hepatocytes and its underlying mechanism of action. Treatment of HepG2 cells with PA induced a significant increase in intracellular p62 and LC3-II levels, suggesting inhibition of autophagy. Furthermore, PA inhibited autophagic flux in HepG2 cells, as monitored using GFP-RFP-LC3. Mechanistically, PA increased the phosphorylation of the Ser12 and Thr29 residues of LC3, which are autophagy inhibition markers, through protein kinase A (PKA) and protein kinase C (PKC) signaling. Finally, PKA and PKC inhibitors restored PA-induced autophagic flux inhibition, reduced intracellular lipid accumulation, and rescued the altered expression of lipogenic genes, such as SREBP-1c, in HepG2 cells. Thus, our study demonstrates the mechanism of autophagy inhibition by PA in hepatocytes and provides a potential therapeutic approach for preventing and treating hepatic steatosis.

Membrane-associated ring-CH-type finger 2 protects against metabolic dysfunction-associated fatty liver disease by targeting fatty acid synthase

OBJECTIVE

Metabolic dysfunction-associated fatty liver disease (MAFLD) has emerged as an important public health concern that poses a significant threat to human health and imposes a substantial economic burden. Research has demonstrated that ubiquitin ligase-mediated substrate protein ubiquitination is a pivotal factor influencing liver lipid homeostasis and metabolic abnormalities in MAFLD. Nevertheless, the specific enzyme molecules implicated in this regulatory process remain to be elucidated. We have published a transcriptome-overexpressing ubiquitin ligase, membrane-associated ring-CH-type finger 2 (MARCH2), in HepG2 cells, and subsequent reanalysis of these transcriptome data revealed a close association between MARCH2 and lipid metabolism.

METHODS

By employing a range of methodologies, including recombinant adeno-associated virus (rAAV) transduction, lentiviral transduction, immunoblotting, quantitative PCR, tissue section staining, ubiquitination assays, serum biochemical analysis, immunoprecipitation, and mass spectrometry, this study investigated the functions and mechanisms of MARCH2 in the progression of MAFLD at the molecular, cellular, and organismal levels.

RESULTS

Overexpression of MARCH2, but not its catalytically inactive ligase variant, inhibited lipid accumulation in HepG2 cells. Additionally, MARCH2 undergoes K48-linked self-polyubiquitination and subsequent proteasomal degradation in response to oleic acid/palmitic acid stimulation. Furthermore, knockout of MARCH2 exacerbates the progression of MAFLD-related phenotypes, including increased body weight, impaired glucose tolerance, reduced insulin sensitivity, hypercholesterolemia, hepatic lipid accumulation, and steatosis, in high-fat diet-fed mice, irrespective of sex. Mechanistically, MARCH2 facilitates the polyubiquitination and degradation of fatty acid synthase (FASN) in the de novo lipogenesis pathway. And liver-specific overexpression of MARCH2 by rAAV effectively reduces FASN levels and further ameliorates MAFLD in ob/ob mice.

CONCLUSIONS

MARCH2 undergoes self-ubiquitination and plays an important role in maintaining the liver lipid homeostasis of MAFLD, and drug intervention in the MARCH2-FASN axis is a promising approach for treating systemic metabolic abnormalities in MAFLD.

Prevotella copri-produced 5-aminopentanoic acid promotes pediatric metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Recent studies suggest an association between the expansion of Prevotella copri and the disease severity in children with metabolic dysfunction-associated steatotic liver disease (MASLD). We aimed to investigate the causative role and molecular mechanisms of P. copri in pediatric MASLD.

METHODS

C57BL/6 J mice aged 3 weeks were fed a high-fat diet (HFD) and orally administered with P. copri for 5 weeks. We assessed the key features of MASLD and the gut microbiota profile. By untargeted metabolomics on mouse fecal samples and the supernatant from P. copri culture, we identified P. copri-derived metabolite and tested its effects in vitro.

RESULTS

In HFD-fed mice, administration of P. copri significantly promoted liver steatosis. Genes associated with inflammation and fibrosis were significantly upregulated in the livers from the HFD + P. copri group compared with those in the livers from the HFD group. In addition, P. copri reduced gut microbial diversity, increased the proportion of Firmicutes and decreased Bacteroidota. Importantly, 5-aminopentanoic acid (5-AVA) was significantly enriched in both mouse feces from the HFD + P. copri group and the culture supernatant of P. copri. In vitro, 5-AVA aggravated palmitic acid-induced lipid accumulation in HepG2 cells and primary mouse hepatocytes. Mechanistically, P. copri-produced 5-AVA exacerbated hepatic steatosis by promoting lipogenesis and fatty acid uptake, while also reducing hepatic very-low-density lipoprotein export.

CONCLUSIONS

Our findings demonstrated that P. copri promotes liver steatosis in HFD-fed juvenile mice through its metabolite 5-AVA, suggesting its potential as a therapeutic target for the management of pediatric MASLD.

Sulfide regulation and catabolism in health and disease

The metabolic pathway of sulfur-containing amino acids in organisms begins with methionine, which is metabolized to produce important sulfur-containing biomolecules such as adenosylmethionine, adenosylhomocysteine, homocysteine, cystine, and hydrogen sulfide (H2S). These sulfur-containing biomolecules play a wide range of physiological roles in the body, including anti-inflammation, antioxidant stress, DNA methylation, protein synthesis, etc., which are essential for maintaining cellular function and overall health. In contrast, dysregulation of the metabolic pathway of sulfur-containing amino acids leads to abnormal levels of sulfur-containing biomolecules, which produce a range of pathological consequences in multiple systems of the body, such as neurodegenerative diseases, cardiovascular diseases, and cancer. This review traces the milestones in the development of these sulfur-containing biomolecules from their initial discovery to their clinical applications and describes in detail the structure, physiochemical properties, metabolism, sulfide signaling pathway, physiopathological functions, and assays of sulfur-containing biomolecules. In addition, the paper also explores the regulatory role and mechanism of sulfur-containing biomolecules on cardiovascular diseases, liver diseases, neurological diseases, metabolic diseases and tumors. The focus is placed on donors of sulfur-containing biological macromolecule metabolites, small-molecule drug screening targeting H2S-producing enzymes, and the latest advancements in preclinical and clinical research related to hydrogen sulfide, including clinical trials and FDA-approved drugs. Additionally, an overview of future research directions in this field is provided. The aim is to enhance the understanding of the complex physiological and pathological roles of sulfur-containing biomolecules and to offer insights into developing effective therapeutic strategies for diseases associated with dysregulated sulfur-containing amino acid metabolism.

Decoding the Liver-Heart Axis in Cardiometabolic Diseases

The liver and heart are closely interconnected organs, and their bidirectional interaction plays a central role in cardiometabolic disease. In this review, we summarize current evidence linking liver dysfunction-particularly metabolic dysfunction-associated steatotic liver disease, alcohol-associated liver disease, and cirrhosis-with an increased risk of heart failure and other cardiovascular diseases. We discuss how these liver conditions contribute to cardiac remodeling, systemic inflammation, and hemodynamic stress and how cardiac dysfunction in turn impairs liver perfusion and promotes hepatic injury. Particular attention is given to the molecular mediators of liver-heart communication, including hepatokines and cardiokines, as well as the emerging role of advanced research methodologies, including omics integration, proximity labeling, and organ-on-chip platforms, that are redefining our understanding of interorgan cross talk. By integrating mechanistic insights with translational tools, this review aims to support the development of multiorgan therapeutic strategies for cardiometabolic disease.

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

Introduction

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

Objectives

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

Methods

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

Results

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

Conclusion

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

Association between atherogenic index of plasma and all-cause mortality and cardiovascular disease among individuals with non-alcoholic fatty liver disease or metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) are common chronic liver diseases worldwide, both of which are closely associated with an increased risk of cardiovascular disease (CVD). Atherogenic index of plasma (AIP), as a biomarker of dyslipidemia, may predict CVD risk and mortality in these patients, but its specific role in patients with NAFLD and MASLD has not been studied in detail. This study adopted a cohort design, using data from the National Health and Nutrition Examination Survey (NHANES, 1988-1994) database, which was conducted by the Centers for Disease Control and Prevention. A total of 12,929 adult participants were analyzed. After participants were grouped according to AIP quartiles, the relationship between AIP levels and CVD risk was explored using multivariate logistic regression models and restricted cubic splines. The relationship between AIP levels and all-cause and CVD mortality was analyzed using multivariate Cox regression models.

RESULTS

Participants with the higher AIP quartiles showed high rates of CVD among participants with NAFLD (Quartile 1: 7.57%; Quartile 2: 10.00%; Quartile 3: 11.63%; Quartile 4: 15.08%). Participants with the higher AIP quartiles showed high rates of CVD among participants with MASLD (Quartile 1: 9.71%; Quartile 2: 11.30%; Quartile 3: 11.14%; Quartile 4: 15.00%). The findings suggested a linear association between the AIP index and the risk of CVD in participants with NAFLD or MASLD. AIP was significantly associated with CVD in the highest quartile of NAFLD or MASLD patients, and the adjusted hazard ratio indicated that high AIP levels were associated with high risk of CVD among participants with NAFLD (HR: 1.77, 95% CI: 1.24, 2.52) and MASLD (HR 1.76, 95% CI: 1.04, 2.98). In addition, higher AIP levels were also associated with increased all-cause mortality and CVD mortality among participants with NAFLD or MASLD.

CONCLUSION

This study showed that AIP is an effective tool for predicting CVD risk and mortality in patients with NAFLD and MASLD. Regular monitoring of AIP levels can help identify high-risk patients early and provide clinical risk assessment before intervention, thereby improving patient management and prognosis. Future studies need to further explore the role of AIP in different ethnic and economic conditions to optimize cardiovascular disease prevention and treatment strategies.

Molecular targets of bempedoic acid and related decoy fatty acids

Disorders of lipid metabolism, including hyperlipidemia, atherosclerosis, and metabolic dysfunction-associated steatotic liver disease, are increasing across the globe. Bempedoic acid (BPA) is a first-in-class drug for the treatment of hypercholesterolemia and cardiac risk reduction, which may particularly benefit those who do not tolerate statins. Inhibition of hepatic ATP-citrate lyase (ACLY) is widely accepted as the main mediator of its observed clinical effects. However, BPA treatment also has ACLY-independent effects on lipid metabolism, as the structural similarity of BPA to endogenous fatty acids allows it to trigger multiple lipid-signaling pathways. Here, we review the molecular targets of BPA and related 'decoy fatty acid' drugs and identify areas where further study is warranted as these molecules are evaluated for clinical indications.

Clinical staging to guide management of metabolic disorders and their sequelae: a European Atherosclerosis Society consensus statement

Obesity rates have surged since 1990 worldwide. This rise is paralleled by increases in pathological processes affecting organs such as the heart, liver, and kidneys, here termed systemic metabolic disorders (SMDs). For clinical management of SMD, the European Atherosclerosis Society proposes a pathophysiology-based system comprising three stages: Stage 1, where metabolic abnormalities such as dysfunctional adiposity and dyslipidaemia occur without detectable organ damage; Stage 2, which involves early organ damage manifested as Type 2 diabetes, asymptomatic diastolic dysfunction, metabolic-associated steatohepatitis (MASH), and chronic kidney disease (CKD); and Stage 3, characterized by more advanced organ damage affecting multiple organs. Various forms of high-risk obesity, driven by maintained positive energy balance, are the most common cause of SMD, leading to ectopic lipid accumulation and insulin resistance. This progression affects various organs, promoting comorbidities such as hypertension and atherogenic dyslipidaemia. Genetic factors influence SMD susceptibility, and ethnic disparities in SMD are attributable to genetic and socioeconomic factors. Key SMD features include insulin resistance, inflammation, pre-diabetes, Type 2 diabetes, MASH, hypertension, CKD, atherogenic dyslipidaemia, and heart failure. Management strategies involve lifestyle changes, pharmacotherapy, and metabolic surgery in severe cases, with emerging treatments focusing on genetic approaches. The staging system provides a structured approach to understanding and addressing the multi-faceted nature of SMD, which is crucial for improving health outcomes. Categorization of SMD abnormalities by presence and progression is aimed to improve awareness of a multi-system trait and encourage a tailored and global approach to treatment, ultimately aiming to reduce the burden of obesity-related comorbidities.

Impact of Genetic Mutations in Hyperhomocysteinemia and Metabolic Syndrome on Physiological Parameters and Quality of Life in Healthy Individuals

BACKGROUND/AIM

Hyperhomocysteinemia (HH) is a metabolic condition linked to cardiovascular and cognitive health risks. This study investigated the prevalence of HH and cardiovascular metabolic syndrome (MS) among patients with symptoms such as fatigue, joint pain, muscle weakness, vertigo, paresthesia, and aphthous stomatitis. The objective was to explore the associations between HH, MS, and quality of life, emphasizing the role of personalized dietary interventions.

PATIENTS AND METHODS

A prospective study was conducted between 2019 and 2023, including 86 patients aged 18 years or older who underwent nutrigenetic testing and provided anthropometric data. Participants were divided into three groups: those with HH (45.3%), those without HH or MS (31.4%), and those with MS but without HH (23.3%). Nutrigenetic analyses assessed genetic predispositions related to nutrient metabolism.

RESULTS

Patients with HH exhibited reduced quality of life, with lower Short Form-12 Health Survey (SF-12) scores compared to other groups. Sex-specific nutrient needs and age-related changes in dietary requirements were identified. Metabolic conditions, including obesity, hypertension, and hypercholesterolemia, inversely impacted nutrient utilization. Physical activity positively correlated with higher demands for folic acid, vitamin B12, zinc, and magnesium.

CONCLUSION

Nutritional interventions targeting these needs effectively improved metabolic health and alleviated symptoms. HH significantly impacts quality of life and metabolic health. Personalized dietary and lifestyle modifications tailored to genetic predispositions, sex, and age are critical for mitigating cardiometabolic risks. These findings lay the groundwork for targeted interventions aimed at improving health outcomes in individuals with HH and MS.

Steam explosion modified pea peptides alleviates hepatosteatosis by regulating lipid metabolism pathways and promoting autophagy

Pea peptides (PP) are natural compounds with multiple biological activities. The purpose of this study was to explore the effect and mechanisms of steam explosion (SE)-modified PP on lipid metabolism in vivo and in vitro. The findings demonstrated that SE-modified PP treatment significantly inhibited lipid accumulation in HepG2 cells induced by free fatty acids (FFA). In addition, SE-modified PP treatment significantly alleviated liver index, improved biochemical parameters in high-fat diet (HFD) mice. SE-modified PP prevented lipid accumulation through regulating AMPK activity and decreased lipogenesis associated proteins (SREBP, FAS, and ACC), upregulated fatty acid oxidation proteins (PPARα, PGC1α, and CPT-1 A). Moreover, SE-modified PP alleviated hepatic oxidative stress by regulating Nrf2/HO-1 pathway, and relieved liver mitochondrial autophagy by upregulating Beclin 1 and LC3B expression. These results demonstrate that SE-modified PP alleviates NAFLD by reducing lipid accumulation, inhibiting hepatic oxidative stress, and increasing liver mitochondrial autophagy, which providing reference for the development of dietary supplements for the treatment and prevention of NAFLD.

Dual inhibition of hepatic ACLY and ACSS2: A synergistic approach to combat NAFLD through lipogenesis reduction and mitochondrial enhancement

Inhibiting de novo lipogenesis (DNL) in hepatocytes is a promising strategy for treating metabolic fatty liver diseases. ACLY, a key enzyme in the DNL pathway, has become a therapeutic target for non-alcoholic fatty liver disease (NAFLD). However, its inhibition shows mixed outcomes, depending on interventions and diets. Evidence suggests ACLY inhibition activates the ACSS2-mediated acetate metabolism and the subsequent DNL, though potential mechanisms and possible consequences remain unclear. This study found that targeting hepatic ACLY with AAV8-shRNA failed to improve NAFLD in mice fed a high-fat, high-fructose diet. Instead, it worsened inflammation and liver injury. ACLY inhibition conditionally upregulated DNL enzymes, but consistently activated the ACSS2-acetyl-CoA pathway and suppressed fatty acid oxidation. Further, ACLY inhibition led to polyunsaturated fatty acid accumulation, triggering mitochondrial dysfunction. The resulting ROS redirected carbon flux into acetate, activating the ACSS2-acetyl-CoA pathway, which promoted lipid biosynthesis and exacerbated mitochondrial dysfunction-a vicious cycle that fueled inflammation and liver damage. Dual inhibition of ACLY and ACSS2 broke this cycle by reducing hepatic acetyl-CoA flux, suppressing DNL, enhancing fatty acid oxidation via PPAR-α activation, and improving mitochondrial function. This combined targeting strategy reduced lipid accumulation, alleviated inflammation, and normalized aminotransferase levels, effectively reversing NAFLD progression.

Integrated Transcriptomic Analysis of Liver and Muscle Tissues Reveals Candidate Genes and Pathways Regulating Intramuscular Fat Deposition in Beef Cattle

Intramuscular fat (IMF) content in beef cattle is a critical determinant of beef meat quality, as it positively influences juiciness, tenderness, and palatability. In China, the crossbreeding of Wagyu and Angus is a prevalent method for achieving a better marbling level. However, the molecular mechanisms governing IMF regulation in these crossbreeds remain poorly understood. To elucidate the mechanism of IMF deposition in these crossbred cattle, we conducted a comparative transcriptomic analysis of longissimus dorsi muscles and livers from cattle with divergent IMF content. RNA-seq revealed 940 and 429 differentially expressed genes (DEGs) in the liver and muscle, respectively, with 60 genes co-differentially expressed (co-DEGs) in both tissues. Functional enrichment highlighted lipid metabolism pathways including fatty acid β-oxidation, PPAR signaling, and glycerolipid metabolism. A total of eleven genes including ACAA2, ACADL, ACOX2, CPT1B, CPT2, LPL, SLC27A1, ACAT1, GK, ACOX3, and ACSM5, were screened as key candidate genes for IMF deposition. A "liver-muscle" regulatory network of IMF deposition was built to illustrate the tissues' interaction. The reliability of the transcriptomic data was verified by quantitative reverse real-time PCR (qRT-PCR). Our findings provide novel molecular markers for increasing the IMF content and accelerating the genetic improvement of beef quality traits in crossbred cattle.

Effect of treadmill walking on cardiometabolic risk factors and liver function markers in older adults with MASLD: a randomized controlled trial

BACKGROUND

Regular walking has been reported to improve metabolically-associated steatotic liver disease (MASLD) by altering the metabolic environment. However, no studies to date have focused on older individuals in both conditions. Therefore, this study aimed to investigate the effects of a 12-week walking intervention on metabolic syndrome risk factors, liver function indicators, and liver ultrasound findings in older adults with both metabolic syndrome and MASLD.

METHODS

A total of 66 participants aged 65-85 years had average ages, heights, and weights of 75.3 ± 5.8 years, 159.3 ± 9.3 cm, and 68.6 ± 6.8 kg, respectively. The participants resided in four senior living communities, and their diets were uniform. The participants from two facilities were assigned to the control group (CON, n = 33), whereas those from the other two facilities were allocated to the treadmill walking program group (WPG, n = 33). Each group comprised 13 males and 20 females. The intervention consisted of a low- to moderate-intensity walking program, conducted for 30 min per day, 6 days per week, totaling 180 min per week. The total daily calorie expenditure was recorded based on the values calculated from the treadmill. The walking intensity was adjusted by modifying the treadmill incline according to each participant's heart rate corresponding to their maximal oxygen consumption (VO₂max). The exercise intensity was set at 50% on Mondays and Fridays, 60% on Tuesdays and Thursdays, and 70% on Wednesdays and Saturdays. Sundays were designated as rest days.

RESULTS

Although there were no significant differences in caloric intake between the groups, the WPG exhibited a 52.5% increase in physical activity levels (p < 0.001), resulting in significant reductions in body weight (-10.2%), fat mass (-17.2%), and abdominal fat (-4.8%). The WPG showed a 16.1% increase in VO₂max, along with significant reductions in systolic blood pressure (-9.6%) and blood glucose (-16.9%), as well as notable improvements in lipid profiles (p < 0.001). The WPG also demonstrated significant reductions in aspartate aminotransferase (-40%), alanine aminotransferase (-23.5%), total protein (-14.4%), albumin (-8.1%), bilirubin (-17.6%), and liver ultrasound scores (-31.8%), with all changes showing significant intergroup differences (p < 0.001).

CONCLUSIONS

Along with a consistent diet, a 12-week walk has been shown to induce significant changes in the body composition and cardiometabolic factors of older adults, as well as notable improvements in liver function markers and imaging findings.

TRIAL REGISTRATION

This study was registered with the Clinical Research Information Service of the Korea Centers for Disease Control and Prevention under Clinical Trials KCT0010079 on 26/12/2024.

Special correlation between diet and MASLD: positive or negative?

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a chronic and systemic metabolic liver disease characterized by the presence of hepatic steatosis and at least one cardiometabolic risk factor (CMRF). The pathogenesis of MASLD involves multiple mechanisms, including lipid metabolism disorders, insulin resistance, inflammatory responses, and the hepato-intestinal axis of metabolic dysfunction. Among these factors, diet serves as both an inducement and a potential remedy in the disease's development. Notably, a high-lipid diet exacerbates fat accumulation, oxidative stress, and inflammatory responses, thereby promoting the progression of MASLD. Consequently, dietary induction models have become vital tools for studying the pathological mechanisms of MASLD, providing a foundation for identifying potential therapeutic targets. Additionally, we summarize the therapeutic effects of dietary optimization on MASLD and elucidate the role of specific dietary components in regulating the hepato-intestinal axis, lipid metabolism, and inhibiting inflammatory responses. In conclusion, studies utilizing animal models of MASLD offer significant insights into dietary therapy, particularly concerning the regulation of lipid metabolism-related and hepatoenteric axis-related signaling pathways as well as the beneficial mechanism of probiotics in hepatoenteric regulation. By understanding the specific mechanisms by which different dietary patterns affect MASLD, we can assess the clinical applicability of current dietary strategies and provide new directions for research and treatment aimed at disease modification.

Cutting-edge biotherapeutics and advanced delivery strategies for the treatment of metabolic dysfunction-associated steatotic liver disease spectrum

Metabolic dysfunction-associated steatotic liver disease (MASLD), a condition with the potential to progress into liver cirrhosis or hepatocellular carcinoma, has become a significant global health concern due to its increasing prevalence alongside obesity and metabolic syndrome. Despite the promise of existing therapies such as thyroid hormone receptor-β (THR-β) agonists, PPAR agonists, FXR agonists, and GLP-1 receptor agonists, their effectiveness is limited by the complexity of the metabolic, inflammatory, and fibrotic pathways that drive MASLD progression, encompassing steatosis, metabolic dysfunction-associated steatohepatitis (MASH), and reversible liver fibrosis. Recent advances in targeted therapeutics, including RNA interference (RNAi), mRNA-based gene therapies, monoclonal antibodies, proteolysis-targeting chimeras (PROTAC), peptide-based strategies, cell-based therapies such as CAR-modified immune cells and stem cells, and extracellular vesicle-based approaches, have emerged as promising interventions. Alongside these developments, innovative drug delivery systems are being actively researched to enhance the stability, precision, and therapeutic efficacy of these biotherapeutics. These delivery strategies aim to optimize biodistribution, improve target-specific action, and reduce systemic exposure, thus addressing critical limitations of existing treatment modalities. This review provides a comprehensive exploration of the underlying biological mechanisms of MASLD and evaluates the potential of these cutting-edge biotherapeutics in synergy with advanced delivery approaches to address unmet clinical needs. By integrating fundamental disease biology with translational advancements, it aims to highlight future directions for the development of effective, targeted treatments for MASLD and its associated complications.

Hepatocellular carcinoma: pathogenesis, molecular mechanisms, and treatment advances

Hepatocellular Carcinoma (HCC), a highly prevalent malignancy, poses a significant global health challenge. Its pathogenesis is intricate and multifactorial, involving a complex interplay of environmental and genetic factors. Viral hepatitis, excessive alcohol consumption, and cirrhosis are known to significantly elevate the risk of developing HCC. The underlying biological processes driving HCC are equally complex, encompassing aberrant activation of molecular signaling pathways, dysregulation of hepatocellular differentiation and angiogenesis, and immune dysfunction. This review delves into the multifaceted nature of HCC, exploring its etiology and the intricate molecular signaling pathways involved in its development. We examine the role of immune dysregulation in HCC progression and discuss the potential of emerging therapeutic strategies, including immune-targeted therapy and tumor-associated macrophage interventions. Additionally, we explore the potential of traditional Chinese medicine (TCM) monomers in inhibiting tumor growth. By elucidating the complex interplay of factors contributing to HCC, this review aims to provide a comprehensive understanding of the disease and highlight promising avenues for future research and therapeutic development.

Sphingosine kinase 2 deficiency impairs VLDL secretion by inhibiting mTORC2 phosphorylation and activating chaperone-mediated autophagy

Hepatic very low-density lipoprotein (VLDL) is essential for maintaining lipid metabolism in the liver. Sphingosine kinases (SphKs) are essential rate-limiting enzymes that catalyze sphingosine phosphorylation to Sphingosine-1-phosphate (S1P). SphKs exist as two isoforms, SphK1 and SphK2, both highly expressed in the liver. SphK1 plays a critical role in regulating hepatic inflammation and drug metabolism. This study aimed to determine whether SphK2 regulates hepatic lipid metabolism, particularly VLDL secretion. Immunohistochemical staining revealed decreased SphK2 protein levels within regions proximal to hepatic lipid accumulation in individuals diagnosed with metabolic dysfunction-associated steatotic liver disease (MASLD). Sphk2-/- mice exhibited spontaneous hepatocyte lipid accumulation and reduced VLDL secretion. Proteomic analysis revealed that SphK2 deficiency impaired soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE) complex interactions involved in vesicular transport and organelle membrane fusion. Furthermore, SphK2 deficiency results in accelerated degradation of the SEC22B, STX5A, and GS28 proteins via chaperone-mediated autophagy (CMA), impeding VLDL transport to the Golgi apparatus. MYH1485, a specific activator of mTOR, induces mTORC2 phosphorylation, thereby inhibiting the degradation of SNARE complexes by CMA and counteracting the lipid accumulation induced by SphK2 deficiency. Exogenous S1P supplementation markedly reversed the reduction in mTORC2 phosphorylation and suppressed CMA, thereby improving VLDL secretion. Our study elucidates an inventive regulatory mechanism by which SphK2 modulates CMA by activating mTORC2 phosphorylation, promoting VLDL secretion, and balancing lipid metabolism in the liver. These findings provide insights into SphK2 function and the underlying mechanisms involved in the regulation of VLDL secretion, which may facilitate MASLD treatment. Proposed model for the role of SphK2 in hepatic VLDL secretion. In hepatocytes, the inhibition of SphK2 activity decreased S1P production, which subsequently downregulates the mTORC2 pathway. This process accelerates the degradation of the SNARE complex components STX5A, GS28, and SEC22B via CMA, which regulates the mutual recognition between VTVs and the Golgi apparatus, ultimately reducing VLDL secretion in hepatocytes.

Leptin acutely increases hepatic triglyceride secretion in patients with lipodystrophy

BACKGROUND AND AIMS

Metreleptin ameliorates hepatic steatosis partially independent of its anorexic action. We previously showed that metreleptin increases hepatic very low-density lipoprotein triglycerides (VLDL1-TG) export in rodents and healthy humans requiring intact hepatic autonomic innervation. The primary aim of this study was to investigate whether metreleptin has anti-steatotic properties in patients with lipodystrophy by increasing VLDL1-TG export. In addition, we present a case of generalized lipodystrophy undergoing metreleptin treatment after liver transplantation, a model for hepatic autonomic denervation.

METHODS

In this randomized, placebo-controlled, crossover trial (EudraCT 2017-003014-22) we assessed the acute effects of a single metreleptin injection in 10 patients (8 females, 2 males; mean age ± SD: 49 ± 14 yrs; 9 familial partial and 1 generalized lipodystrophy) on hepatic VLDL1-TG secretion and hepatocellular lipid content (HCL) measured via an intravenous fat emulsion test and 1H-magnetic resonance spectroscopy, respectively.

RESULTS

We found that a single injection of metreleptin increased hepatic VLDL1-TG secretion by 75 % (mean difference ± SD: +219 ± 149 mg/h metreleptin vs. placebo; p = 0.001), without significant changes in HCL within 3 h (mean difference ± SD: -8 ± 14 % metreleptin vs. placebo, p = 0.14). Metreleptin therapy in a patient with generalized lipodystrophy following liver transplantation failed to ameliorate hepatic steatosis despite improving glucose and lipid metabolism.

CONCLUSIONS

Leptin acutely increases hepatic VLDL1-TG secretion in patients with lipodystrophy, likely contributing to metreleptin's body weight-independent anti-steatotic effects. The case report suggests that intact autonomic liver innervation may be required for this action, warranting further research.

HDL-Cholesterol and Triglycerides Dynamics: Essential Players in Metabolic Syndrome

Metabolic syndrome (MetS) is a complex cluster of interrelated metabolic disorders that significantly elevate the risk of cardiovascular disease, making it a pressing public health concern worldwide. Among the key features of MetS, dyslipidemia-characterized by altered levels of high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG)-plays a crucial role in the disorder's progression. This review aims to elucidate the intricate interplay between HDL-C and TG within the context of lipid metabolism and cardiovascular health, while also addressing the detrimental impact of various cardiovascular risk factors and associated comorbidities. The dynamics of HDL-C and TG are explored, highlighting their reciprocal relationship and respective contributions to the pathophysiology of MetS. Elevated levels of TGs are consistently associated with reduced concentrations of HDL-C, resulting in a lipid profile that promotes the development of vascular disease. Specifically, as TG levels rise, the protective cardiovascular effects of HDL-C are diminished, leading to the increased accumulation of pro-atherogenic TG-rich lipoproteins and low-density lipoprotein particles within the vascular wall, contributing to the progression of atheromas, which can ultimately result in significant ischemic cardiovascular events. Ultimately, this paper underscores the significance of HDL and TG as essential targets for therapeutic intervention, emphasizing their potential in effectively managing MetS and reducing cardiovascular risk.

Prevalence and impact of metabolic associated fatty liver disease in non-metastatic breast cancer women at initial diagnosis: a cross-sectional study in China

PURPOSE

The epidemiologic data of metabolic associated fatty liver disease (MAFLD) in breast cancer (BC) patients remains limited. We aimed to investigate the prevalence and clinicopathological characteristics of hepatic steatosis (HS) and MAFLD in Chinese BC women at initial diagnosis.

METHODS

3217 non-metastatic primary BC women with MAFLD evaluation indexes at initial diagnosis and 32,170 age-matched (in a 1:10 ratio) contemporaneous health check-up women were enrolled.

RESULTS

The prevalence of HS (21.5% vs. 19.7%, p = 0.013) and MAFLD (20.8% vs. 18.6%, p = 0.002) were significantly higher in BC women than in health check-ups, respectively. Meanwhile, the prevalence of HS/MAFLD among elderly BC women (≥ 60 years) was significantly higher than the health check-ups (38.7%/37.6% vs 31.9%/30.8%), respectively. In BC women with HS/MAFLD, the prevalence of overweight/obesity was up to 85.7%/88.6%, dyslipidemia and elevated blood pressure were 63.2%/63.7% and 59.7%/61.7%, respectively. No statistical significance of the expressions of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor 2 (HER-2) and Ki67 were found between BC women with HS/MAFLD and BC women without HS/MAFLD. After adjustment, BC women with HS showed significantly higher risk of lymph node metastasis than BC women without HS. Subjects with HS/MAFLD had higher risks of overweight/obesity, dyslipidemia, elevated blood pressure, hyperuricemia, and elevated enzymes than those without HS/MAFLD.

CONCLUSIONS

Compared with health check-ups, BC patients have higher prevalence of HS/MAFLD. HS/MAFLD coexist with high prevalence of metabolic complications, and the risk of lymph node metastasis was significantly higher in BC women with HS than in BC women without HS.

S-adenosylmethionine deficit disrupts very low-density lipoprotein metabolism promoting liver lipid accumulation in mice

Hepatic deletion of methionine adenosyltransferase-1a (Mat1a) in mice reduces S-adenosylmethionine (SAMe), a key methyl donor essential for many biological processes, which promotes the development and progression of metabolic dysfunction-associated steatotic liver disease (MASLD). Hyperglycemia and reduced MAT1A expression, along with low SAMe levels, are common in MASLD patients. This study explores how Mat1a-knockout (KO) hepatocytes respond to prolonged high glucose conditions, focusing on glucose metabolism and lipid accumulation. Hepatocytes from methionine adenosyltransferase-1a-knockout (Mat1a-KO) mice were incubated in high glucose conditions overnight, allowing for analysis of key metabolic intermediates and gene expression related to glycolysis, gluconeogenesis, glyceroneogenesis, phospholipid synthesis, and very low density lipoprotein (VLDL) secretion. SAMe deficiency in Mat1a-KO hepatocytes led to reduced protein methyltransferase-1 activity, resulting in increased expression of glycolytic enzymes (glucokinase, phosphofructokinase, and pyruvate kinase) and decreased expression of gluconeogenic enzymes (phosphoenolpyruvate carboxykinase, fructose-1,6-bisphosphatase, and glucose-6-phosphatase). These alterations led to a reduction in dihydroxyacetone phosphate (DHAP), which subsequently inhibited mammalian target of rapamycin complex 1 (mTORC1) activity. This inhibition resulted in decreased phosphatidylcholine synthesis via the CDP-choline pathway and impaired VLDL secretion, ultimately causing lipid accumulation. Thus, under high glucose conditions, SAMe deficiency in hepatocytes depletes DHAP, inhibits mTORC1 activity, and promotes lipid buildup.

Probiotics for the treatment of hyperlipidemia: Focus on gut-liver axis and lipid metabolism

Hyperlipidemia, a metabolic disorder marked by dysregulated lipid metabolism, is a key contributor to the onset and progression of various chronic diseases. Maintaining normal lipid metabolism is critical for health, as disruptions lead to dyslipidemia. The gut and liver play central roles in lipid homeostasis, with their bidirectional communication, known as the gut-liver axis, modulated by bile acids (BAs), gut microbiota, and their metabolites. BAs are essential for regulating their own synthesis, lipid metabolism, and anti-inflammatory responses, primarily through the farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5). Available evidence suggests that high-fat diet-induced the gut microbiota dysbiosis can induce "leaky gut," allowing toxic microbial metabolites to enter the liver via portal circulation, triggering liver inflammation and lipid metabolism disturbances, ultimately leading to hyperlipidemia. Extensive studies have highlighted the roles of probiotics and Traditional Chinese Medicine (TCM) in restoring gut-liver axis balance and modulating lipid metabolism through regulating the levels of lipopolysaccharides, short-chain fatty acids, and BAs. However, the therapeutic potential of probiotics and TCM for hyperlipidemia remains unclear. Here, firstly, we explore the intricate interplay among gut microbiota and metabolites, lipid metabolism, gut-liver axis, and hyperlipidemia. Secondly, we summarize the mechanisms by which probiotics and TCM can alleviate hyperlipidemia by altering the composition of gut microbiota and regulating lipid metabolism via the gut-liver axis. Finally, we emphasize that more clinical trials of probiotics and TCM are necessary to examine their effects on lipid metabolism and hyperlipidemia.

Impaired ApoB secretion triggers enhanced secretion of ApoE to maintain triglyceride homeostasis in hepatoma cells

Apolipoprotein B (ApoB) is essential for the assembly and secretion of triglyceride (TG)-rich VLDL particles, and its dysfunction is linked to metabolic disorders, including dyslipidemia and liver steatosis. However, less attention has been paid to whether and how other apolipoproteins play redundant or compensatory roles when the ApoB function is compromised. Here, we investigated the effects of microsomal triglyceride transfer protein (MTP), which mediates lipidation of nascent ApoB, on ApoE function. We observed a paradoxical increase in ApoE secretion resulting from increased expression in MTP inhibitor (MTPi)-treated human hepatoma cells. This phenotype was recapitulated in APOB-knockout cells and was associated with impaired ApoB secretion. While MTP-dependent transfer of neutral lipids is dispensable for ApoE secretion, TG biosynthesis, redundantly catalyzed by DGAT1 and DGAT2, is required for efficient ApoE secretion in hepatoma cells. ApoE colocalizes with lipid droplets near the Golgi apparatus and mediates TG export in an ApoB-independent fashion. We found that simultaneous inhibition of both ApoE and ApoB, but not inhibition of either alone, led to TG accumulation in hepatoma cells, indicating that both proteins function redundantly to control TG content. Validation studies in primary human hepatocytes (PHHs) demonstrated DGAT2-dependent secretion of ApoE. While MTPi treatment did not elevate ApoE secretion, it induced increased sialylation of ApoE in the supernatants of PHHs. These results show that enhanced ApoE secretion compensates for the impaired ApoB function to maintain the lipid homeostasis, providing an alternative route to modulate lipid turnover in hepatoma cells.

Curcumin Analog J7 Attenuates Liver Fibrosis and Metabolic Dysregulation in a Rat Model of Type 2 Diabetes via Modulation of TGF-β/Smad and NF-κB/BCL-2/BAX Pathways

Objective

To evaluate the therapeutic potential of the curcumin analog J7 in protecting the liver and regulating glucose and lipid metabolism in rats with type 2 diabetes.

Methods

Bioinformatics methods were used to identify signaling pathways linked to diabetic liver disease. Diabetic rats were treated with curcumin, low-dose J7, or high-dose J7, and liver function and fibrosis were assessed through biochemical analyses, histopathology, immunohistochemistry, and ELISA.

Results

J7 administration significantly improved lisver function, reduced fibrosis, and regulated metabolic profiles in diabetic rats. J7 downregulated TGF-β1, NF-κB p65, and BAX, while upregulating BCL-2, showing superior effects to traditional curcumin in reducing TGF-β1 and inhibiting α-SMA expression.

Conclusion

J7 demonstrates potential as a therapeutic agent for managing liver complications in type 2 diabetes, effectively attenuating liver fibrosis and regulating metabolism through the modulation of key signaling pathways and proteins.

LIMA1 O-GlcNAcylation Promotes Hepatic Lipid Deposition through Inducing β-catenin-Regulated FASn Expression in Metabolic Dysfunction-Associated Steatotic Liver Disease

Hepatic lipid deposition is a key factor in progressing metabolic dysfunction-associated steatotic liver disease (MASLD). This study investigates the impact of the LIM domain and actin-binding protein 1 (LIMA1) on hepatic steatotic in MASLD and explore the underlying mechanisms. Increased levels of LIMA1 is observed in both serum and serum sEV of metabolic dysfunction-associated steatohepatitis (MASH) patients compared to healthy controls, with AUROC values of 0.76 and 0.86, respectively. Furthermore, increased LIMA1 O-GlcNAcylation is observed in mouse models of MASLD, and steatotic hepatocytes. Mechanistic studies revealed that steatosis upregulated Host cell factor 1 (HCF1) and O-GlcNAc transferase (OGT) expression, leading to catalyzed O-GlcNAcylation at the T662 site of LIMA1 and subsequent inhibition of its ubiquitin-dependent degradation. O-GlcNAcylation of LIMA1 enhances hepatocyte lipid deposition by activating β-catenin/FASn-associated signaling. Additionally, compared with their AAV8-TBG-LIMA1-WT counterparts, AAV8-TBG-LIMA1ΔT662 injection exhibited decreases in systemic insulin resistance, steatosis severity, inflammation and fibrosis in HFD-fed and CDAHFD-fed LIMA1 HKO (hepatocyte-specific knockout) mice. Moreover, LTH-sEV-mediated delivery of LIMA1 promoted MASLD progression by promoting hepatic stellate cell (HSC) activation. The findings suggest that serum sEV LIMA1 may be a potential noninvasive biomarker and therapeutic target for individuals with MASH.

Research Progress on Anti-Hyperlipidemia Peptides Derived from Foods

Hyperlipidemia is a metabolic disorder in which cholesterol (TC) and triglycerides (TGs) in the blood exceed the normal physiological levels. The incidence of the condition has continued to rise in recent years, posing a serious threat to public health. Its clinical treatment mainly relies on drug interventions, such as statins, fibrate, and niacin. Although these drugs have shown some efficacy in the treatment of hyperlipidemia, their adverse effects cannot be ignored. In contrast, naturally derived peptides have gradually become potential candidates for the prevention and treatment of hyperlipidemia due to their strong anti-hyperlipidemic activity and safety; examples of such peptides include those from dairy products, grains, legumes, and seafood. This review systematically summarizes peptides with anti-hyperlipidemic activity and analyzes their mechanisms of action, providing a theoretical basis for further research. In addition, we also outline some challenges facing the application of peptides, hoping to prevent hyperlipidemia and reduce its incidence by encouraging the consumption of foods rich in anti-hyperlipidemia peptides.

Exploring the severity and risk factors of non-alcoholic fatty liver disease using the SAF scoring system

Objective

The steatosis, activity, and fibrosis (SAF) score is a histological scoring system developed by the European Association for the Study of the Liver to evaluate liver biopsy samples in cases of non-alcoholic fatty liver disease (NAFLD). Based on histopathological results and SAF scores, NAFLD patients were categorized into mild, moderate, and severe groups. We compared the differences between these groups and identified the risk factors influencing lesion severity.

Methods

We gathered data from 539 NAFLD patients who underwent percutaneous liver biopsy confirmation at Beijing Ditan Hospital between January 2018 and December 2022. All biopsies were graded according to the SAF scoring system, and the severity of the disease was classified as mild, moderate, or severe. We compared the differences in gender, age, BMI, history of diabetes, history of hypertension, aspartate aminotransferase (AST), alanine aminotransferase (ALT), serum cholesterol levels, and other factors among NAFLD patients with varying degrees of disease severity. Additionally, we explored the risk factors that influenced the severity of lesions.

Results

A total of 539 patients were enrolled in this study, with ages ranging from 6 to 79 years. Among them, there were 325 men and 214 women in an average age of 39 ± 13 years. The patients were divided into three groups based on disease severity: mild NAFLD group (162 cases), moderate NAFLD group (210 cases), and severe NAFLD group (167 cases). The results showed significant differences between the three groups in terms of age composition, high-calorie diet, family history of hypertension, ALT, AST, GGT, total bile acids, cholinesterase, glycosylated albumin, blood glucose, uric acid, type III procollagen, serum human laminin, liver stiffness, and hepatic steatosis.

Conclusion

BMI, uric acid, AST, type III procollagen, liver stiffness, and hepatic steatosis play critical roles in the progression of NAFLD and contribute to high pathological SAF scores in NAFLD patients.

Molecular Mechanism of Microgravity-Induced Intestinal Flora Dysbiosis on the Abnormalities of Liver and Brain Metabolism

Space flight has many adverse effects on the physiological functions of astronauts. Certain similarities have been observed in some physiological processes of rodents and astronauts in space, although there are also differences. These similarities make rodents helpful models for initial investigations into space-induced physiological changes. This study uses a 3D-Clinostat to simulate microgravity and explores the role of microgravity in space flight-induced liver and brain abnormalities by comparing changes in the gut microbiota, serum metabolites, and the function and physiological biochemistry of liver and brain tissues between the simulated microgravity (SMG) group mice and the wild type (WT) group mice. The study, based on hematoxylin-eosin (HE) staining, 16S sequencing technology, and non-targeted metabolomics analysis, shows that the gut tissue morphology of the SMG group mice is abnormal, and the structure of the gut microbiota and the serum metabolite profile are imbalanced. Furthermore, using PICRUST 2 technology, we have predicted the functions of the gut microbiota and serum metabolites, and the results indicate that the liver metabolism and functions (including lipid metabolism, amino acid metabolism, and sugar metabolism, etc.) of the SMG group mice are disrupted, and the brain tissue metabolism and functions (including neurotransmitters and hormone secretion, etc.) are abnormal, suggesting a close relationship between microgravity and liver metabolic dysfunction and brain dysfunction. Additionally, the high similarity in the structure of the gut microbiota and serum metabolite profile between the fecal microbiota transplant (FMT) group mice and the SMG group mice, and the physiological and biochemical differences in liver and brain tissues compared to the WT group mice, suggest that microgravity induces imbalances in the gut microbiota, which in turn triggers abnormalities in liver and brain metabolism and function. Finally, through MetaMapp analysis and Pearson correlation analysis, we found that valeric acid, a metabolite of gut microbiota, is more likely to be the key metabolite that relates to microgravity-induced gut microbiota abnormalities, disorders of amino acid and lipid metabolism, and further induced metabolic or functional disorders in the liver and brain. This study has significant practical application value for deepening the understanding of the adaptability of living organisms in the space environment.

Liver function differences in atherosclerotic cardiovascular disease: a multi-ethnic dual-cohort retrospective study

Background and aims

Liver function plays a pivotal role in the initiation and progression of atherosclerotic cardiovascular disease (ASCVD). Exploring the potential associations between liver function assessment indicators and ASCVD is essential for understanding the liver's involvement in ASCVD pathogenesis. However, the specific relationships between these indicators and ASCVD are still debated. This study aims to conduct an in-depth comparative analysis of variations in various liver function assessment indicators among populations of ASCVD patients.

Methods

A dual-cohort retrospective cross-sectional study design was employed, using data from 15,943 ASCVD patients at the First Hospital of Jilin University and 472 ASCVD patients from the National Health and Nutrition Examination Survey (NHANES) database. Liver function indicators, including enzymatic, protein synthesis, bilirubin metabolism indices, and lipid profile parameters, were analyzed. Inclusion and exclusion criteria were rigorously applied, followed by univariate regression, multivariate regression and stratified subgroup analyses.

Results

Hepatocyte damage indicators (aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transferase, alkaline phosphatase) and total bilirubin were identified as risk factors for ASCVD. Albumin showed a protective effect. Globulin levels differed significantly between cohorts. Cholinesterase (cohort 1) and total protein, total cholesterol (cohort 2) showed no significant changes in ASCVD patients.

Conclusion

Many liver function indicators are correlated with ASCVD. There are differences in these indicators between ASCVD patients and healthy volunteers. Although some indicators may be weakly correlated due to confounding factors, this study still provides a scientific rationale for developing more precise ASCVD prevention and treatment strategies in the future.

The association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and pulmonary function: evidence from NHANES 2007-2012

Background

This research aims to explore the potential association between lung function and the ratio of non-high-density lipoprotein cholesterol (NHL) to high-density lipoprotein cholesterol (NHHR). Previous research has shown that lipid metabolism imbalance is closely linked to cardiovascular disease, however, there is a lack of information regarding its impact on lung function.

Methods

This research used information from the National Health and Nutrition Examination Survey (NHANES) spanning the years 2007 to 2012, including a large-scale sample of 9,498 adults aged 20 years and older. A cross-sectional study employing multivariable regression models was aimed at examining the relevance between NHHR and indicators of lung function (FEV1, FVC, and FEV1/FVC). Adjustments were made for a wide range of confounding factors, encompassing race, gender, age, BMI, smoking status, physical activity, diabetes, alcohol consumption, and education level. Data analysis included categorizing NHHR into quartiles and using trend tests to evaluate dose-response relationships between NHHR quartiles and lung function. Sensitivity analyses were conducted by excluding participants with asthma and COPD to ensure the reliability of the results.

Results

The results manifested a significant correlation between decreased FEV1 and FVC values and elevated NHHR, most notably within the highest quartile of NHHR (Q4), where the association was most pronounced. Additionally, trend test results indicated a significant linear negative correlation between NHHR and both FEV1 and FVC. However, the correlation between FEV1/FVC and NHHR showed a nonlinear U-shaped pattern. Suggesting differential impacts of NHHR on various lung function indicators. The findings' robustness was shown by sensitivity analysis, which revealed that even after omitting people with asthma and COPD, the negative correlation between NHHR and FEV1 and FVC remained significant.

Conclusion

This research emphasizes the significance of tracking lipid levels in evaluating respiratory health and offers early evidence in favor of NHHR as a probable biomarker for respiratory function. Further longitudinal research has occasion to prove the causal relationship between NHHR and lung function and to explore its underlying biological mechanisms.

Effects of Sodium Acetate and Sodium Butyrate on the Volatile Compounds in Mare's Milk Based on GC-IMS Analysis

This study aims to explore the impact of adding sodium acetate and sodium butyrate on the composition, blood biochemical parameters, and volatile flavor compounds of lactating mares' milk. By assessing the influence of these additives on milk flavor enhancement, the findings provide scientific evidence for optimizing flavor characteristics and offer new strategies for improving the sensory attributes of mare milk products. Eighteen lactating Yili mares were randomly assigned to three groups: a control group, a sodium acetate group (85 mg/kg·BM-1), and a sodium butyrate group (85 mg/kg·BM-1). The experiment lasted 90 days, with milk yield recorded on days 0, 30, 60, and 90. Milk samples were collected on day 60 (peak lactation) for compositional analysis, and GC-IMS was employed to identify and quantify volatile compounds. Additionally, blood samples were drawn from the jugular vein before morning feeding on day 60 using heparinized tubes to assess key biochemical markers, including glucose, triglycerides, total cholesterol, and urea. The results revealed the following findings: (1) Milk yield and composition: The addition of sodium acetate and sodium butyrate had no significant effect on milk yield. However, both treatment groups exhibited significantly or extremely significantly higher milk fat content compared to the control group, whereas milk protein and lactose levels remained largely unchanged. (2) Blood biochemical indicators: The sodium butyrate group showed an extremely significant increase in urea levels compared to the sodium acetate and control groups. Glucose levels in the sodium acetate group were also significantly higher than in the control group. Moreover, triglyceride levels were markedly elevated in the sodium butyrate group compared to the sodium acetate group, while total bilirubin concentrations were significantly higher in the sodium acetate group than in the control group. (3) Volatile compounds: The addition of these additives led to a significant increase in the diversity and concentration of volatile compounds in mare milk. Notably, esters, aldehydes, and ketones showed substantial enrichment in both treatment groups. The relative abundance of esters such as butyl acetate, L-lactic acid ethyl ester, 1-pentene-3-ol, pentanol, and 3-pentanone increased, alongside a significant rise in aldehydes and ketones, including 2-heptenal and 3-pentanone. In conclusion, sodium acetate and sodium butyrate enhance milk flavor by modulating milk composition and metabolic parameters, providing a scientific foundation for improving the quality of mare milk products.

Deciphering significances of autophagy in the development and metabolism of adipose tissue

The mechanisms of adipose tissue activation and inactivation have been a hot topic of research in the last decade, from which countermeasures have been attempted to be found against obesity as well as other lipid metabolism-related diseases, such as type 2 diabetes mellitus and non-alcoholic fatty liver disease. Autophagy has been shown to be closely related to the regulation of adipocyte activity, which is involved in the whole process including white adipocyte differentiation/maturation and brown or beige adipocyte generation/activation. Dysregulation of autophagy in adipose tissue has been demonstrated to be associated with obesity. On this basis, we summarize the pathways and mechanisms of autophagy involved in the regulation of lipid metabolism and present a review of its pathophysiological roles in lipid metabolism-related diseases, in the hope of providing ideas for the treatment of these diseases.

Estimated sdLDL-C as a biomarker of hepatic steatosis severity in MASLD: a retrospective study

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent chronic liver disease worldwide. However, there is a lack of cost-effective and accurate biomarkers to assess the degree of hepatic steatosis. Estimated small dense low-density lipoprotein cholesterol (EsdLDL-C), a calculated value derived from triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) levels, has emerged as a potential indicator. This study aimed to explore the relationship between EsdLDL-C and the severity of hepatic steatosis.

METHODS

This single-center retrospective study estimated and directly measured small dense low-density lipoprotein cholesterol (sdLDL-C) in 1,969 patients who underwent serum lipid testing at Changzhou Third People's Hospital between January and July 2024. Among these, 461 patients diagnosed with MASLD were included in the study. These patients were further classified into mild (Mil) and moderate-to-severe (Mod-Sev) groups based on controlled attenuation parameter (CAP) values to explore the relationship between EsdLDL-C and the severity of hepatic steatosis.

RESULTS

The correlation coefficient (R) between EsdLDL-C and DsdLDL-C was 0.837, with a bias of 0.223. Both EsdLDL-C (OR 1.095, 95% CI 1.029-1.180) and visceral fat area (VFA) (OR 1.019, 95% CI 1.010-1.028) were identified as independent risk factors for Mod-Sev steatosis compared to the Mil group. After adjusting for all confounders, patients with MASLD had a 1.155-fold increased risk of developing Mod-Sev hepatic steatosis for each unit increase in EsdLDL-C. Furthermore, EsdLDL-C demonstrated good predictive value for Mod-Sev steatosis in MASLD patients, with an area under the curve (AUC) of 0.825 (95% CI 0.784-0.867).

CONCLUSIONS

EsdLDL-C may serve as a practical and cost-effective biomarker for identifying high-risk MASLD patients.

TRIAL REGISTRATION

The retrospective study was approved by the Ethics Committee of Changzhou Third People's Hospital (02 A-A20230015), and a waiver of informed consent was agreed to, as the data were obtained from medical records, and a waiver of informed consent would not have affected the participants.

Identification and verification of biomarkers associated with arachidonic acid metabolism in non-alcoholic fatty liver disease

Elevated arachidonic acid metabolism (AAM) has been linked to the progression of non-alcoholic fatty liver disease (NAFLD). However, the specific role of AAM-related genes (AAMRGs) in NAFLD remains poorly understood. To investigate the involvement of AAMRGs in NAFLD, this study analyzed datasets GSE89632 and GSE135251 from the Gene Expression Omnibus (GEO) and Molecular Signatures Database (MSigDB). Differential expression analysis revealed 2256 differentially expressed genes (DEGs) between NAFLD and control liver tissues. Cross-referencing these DEGs with AAMRGs identified nine differentially expressed AAMRGs (DE-AAMRGs). Least absolute shrinkage and selection operator (LASSO) and univariate logistic regression analyses pinpointed five biomarkers-CYP2U1, GGT1, PLA2G1B, GPX2, and PTGS1-demonstrating significant diagnostic potential for NAFLD, as validated by receiver operating characteristic (ROC) analysis. These biomarkers were implicated in pathways related to AAM and arachidonate transport. An upstream regulatory network, involving transcription factors (TFs) and MicroRNAs (miRNAs), was constructed to explore the regulatory mechanisms of these biomarkers. In vivo validation using a NAFLD mouse model revealed liver histopathological changes, and quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot (WB) analyses confirmed the upregulation of biomarker expression, particularly PTGS1, in NAFLD. The bioinformatic analysis identified five AAM-related biomarkers, enhancing the understanding of NAFLD pathogenesis and offering potential diagnostic targets.

Establishing the Role of Liver Fatty Acid-Binding Protein in Post-Golgi Very-Low-Density Lipoprotein Trafficking Using a Novel Fluorescence-Based Assay

The liver plays a crucial role in maintaining lipid homeostasis by converting toxic free fatty acids into VLDL, which the body uses for energy. Even minor changes in VLDL formation and secretion can result in serious health conditions such as atherosclerosis and non-alcoholic fatty liver disease. Despite the importance of VLDL, the proteins and signaling pathways involved in its regulation remain largely unknown. This study aims to develop a novel methodology to study intracellular VLDL transport events and explore the role of liver fatty acid-binding protein (LFABP) in VLDL transport and secretion. Current methods to study VLDL are often tedious, time-consuming, and expensive, underscoring the need for an alternative approach. We designed a new immunofluorescence-based assay to track the formation and secretion of VLDL in cells over time using fluorescently tagged TopFluor oleic acid. Confocal microscopy confirmed that TopFluor oleic acid enters hepatocytes and colocalizes with the ER, Golgi, and plasma membrane. Additionally, the collection of cell culture media revealed that TopFluor was incorporated into VLDL particles, as confirmed by fluorescence readings and ApoB100 immunoblots. This novel assay provides a valuable tool for further research into the mechanisms of VLDL regulation and the development of potential therapeutic targets for related diseases. Utilizing this assay, we identified LFABP as a key regulatory protein in post-Golgi VLDL trafficking. Our data suggest that LFABP plays a crucial role in this process, and its functional impairment leads to reduced VLDL secretion.

Role of USF1 in activating CYBA transcription and influencing NADPH-ROS-mediated oxidative stress and lipid accumulation in non-alcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) progression is relevant to oxidative stress, while NADPH oxidase can produce ROS. This study explored how the upstream stimulatory factor 1 (USF1) regulates cytochrome b-245 alpha chain (CYBA) expression through the NADPH-ROS pathway and its impact on oxidative stress and lipid accumulation in NAFLD. Bioinformatics analysis identified CYBA as a gene with altered expression in NAFLD. Mouse and cell models of NAFLD were established through high-fat diet (HFD) and palmitic acid (PA) treatment respectively. CYBA and USF1 expression was modulated using RNA interference, and their effects on NAFLD progression were then examined. ChIP and dual-luciferase reporter assays were performed to confirm the transcriptional regulation of CYBA by USF1. Elevated CYBA expression was observed in NAFLD. Reduced NADPH oxidase activity, oxidative stress, lipid accumulation, and inflammation were observed in NAFLD models after knocking down CYBA. USF1 was found to bind to the CYBA promoter and activate its transcription. Similar effects as CYBA knockdown on NAFLD were achieved by knocking down USF1. The protective impacts of USF1 silencing on NAFLD were reversed by overexpressing CYBA. In summary, this study demonstrates that USF1 mediates the transcriptional activation of CYBA, increasing NADPH-ROS-derived oxidative stress and lipid accumulation in NAFLD.

Clinical significance of small dense low-density lipoprotein cholesterol measurement in type 2 diabetes

Low-density lipoprotein cholesterol (LDL-C) is known to be a causal substance of atherosclerosis, but its usefulness as a predictive biomarker for atherosclerotic cardiovascular disease (ASCVD) is limited. In patients with type 2 diabetes (T2D), LDL-C concentrations do not markedly increase, while triglycerides (TG) concentrations are usually elevated. Although TG is associated with ASCVD risk, they do not play a direct role in the formation of atheromatous plaques. TG changes the risk of ASCVD in a way that is dependent on LDL-C, and TG is the primary factor in reducing LDL particle size. Small dense (sd)LDL, a potent atherogenic LDL subfraction, best explains the "Atherogenic Duo" of TG and LDL-C. Although hypertriglyceridemia is associated with small-sized LDL, patients with severe hypertriglyceridemia and low LDL-C rarely develop ASCVD. This suggests that quantifying sdLDL is more clinically relevant than measuring LDL size. We developed a full-automated direct sdLDL-C assay, and it was proven that sdLDL-C is a better predictor of ASCVD than LDL-C. The sdLDL-C level is specifically elevated in patients with metabolic syndrome and T2D who have insulin resistance. Due to its clear link to metabolic dysfunction, sdLDL-C could be named "metabolic LDL-C." Insulin resistance/hyperinsulinemia promotes TG production in the liver, causing steatosis and overproduction of VLDL1, a precursor of sdLDL. sdLDL-C is closely associated with steatotic liver disease and chronic kidney disease, which are common complications in T2D. This review focuses on T2D and discusses the clinical significance of sdLDL-C including its composition, pathophysiology, measurements, association with ASCVD, and treatments.

Qige Decoction attenuated non-alcoholic fatty liver disease through regulating SIRT6-PPARα-mediated fatty acid oxidation

BACKGROUND

Sirtuin 6 (SIRT6), a potential therapeutic target for non-alcoholic fatty liver disease (NAFLD), has been shown to regulate fatty acid oxidation (FAO) by interacting with peroxisome proliferator-activated receptor α (PPARα). However, the impact of SIRT6-PPARα pathway on NAFLD phenotype has not yet been reported. Qige decoction (QG), a traditional Chinese medicine (TCM) formula, is widely applied to treat disorders of glycolipid metabolism. Our previous experiments showed that QG reduced hepatic steatosis and provided preliminary evidence that QG may promote FAO. However, a thorough understanding of molecular mechanisms by which QG regulates FAO requires further investigation.

PURPOSE

To investigate the role of SIRT6-PPARα signalling pathway on NAFLD phenotype and explore the mechanism by which QG improves NAFLD and its relationship with FAO regulated by SIRT6-PPARα signalling pathway.

METHODS

In vivo study, NAFLD mice induced by high fat diet (HFD) were divided into two parts. The first part involved four groups: control (CON), model (MOD), PPARα agonist (WY-14,643, WY), and SIRT6 inhibitor (OSS-128,167, OS) groups. The second part involved five groups: CON group, MOD group, positive drug (POS) group, low dose QG (QGL) group, and high dose QG (QGH) group. Widely-targeted lipidomic were performed by UHPLC-QTOF/MS to analyse differential lipids (DELs) in the liver, while differentially expressed genes (DEGs) were analysed by transcriptome analysis on the Illumina sequencing platform. In vitro study, co-immunoprecipitation and dual luciferase assay were employed to further identify the molecular mechanisms of SIRT6-PPARα interaction. The lentiviral vector, TG assay, and acetyl-CoA assay were used to clarify the indispensable role of the SIRT6-PPARα signalling pathway on QG amelioration of lipid accumulation in vitro.

RESULTS

Down-regulation of SIRT6 inhibited PPARα-mediated FAO and aggravated lipid accumulation in hepatocytes both in vivo and in vitro. SIRT6 bound to PPARα in HepG2 cells; however, SIRT6 activation of the PPARα promoter was not detected. Along with QG reduced hepatocyte lipid accumulation, SIRT6-PPARα signalling pathway was upregulated in vivo and in vitro. However, the alleviating effect of QG on lipid accumulation was blocked by SIRT6 silencing in vitro.

CONCLUSION

This study verified that SIRT6-PPARα signalling pathway inhibition exacerbated NAFLD dyslipidaemia and hepatic steatosis. In addition, this study provided the first in-depth analysis of the molecular mechanisms by which QG ameliorates NFALD, involving promotion of FAO through activation of the SIRT6-PPARα signalling pathway. Our study offers significant insights for the clinical application of QG.

Elucidating the effect of camel α-lactalbumin in modulating obesity-related metabolic disorders in an obese rat model

Camel α-Lactalbumin (α-LACc) has been shown to exert bioactivities for Reactive oxygen species (ROS) scavenging and anti-inflammation, showing the ability to treat obesity-related metabolic disorders. Herein, we present a novel process to purify α-LACc in a single chromatographic step from camel whey in a flow-through format. We also demonstrate the role of α-LACc modulation strategies for the treatment of obesity. An in-vivo study was systematically carried-out, in which an intragastric administration of α-LACc in rats experiencing obesity showed ameliorating effect on hepatic steatosis and dyslipidemia. In addition, we demonstrated that the reduction of inflammation and oxidative stress by α-LACc was effective, and importantly, the enhancement of antioxidant defenses was achieved. Furthermore, we found that the peroxynitrite scavenging ability of α-LACc could help restore the hepatorenal function. Finally, we showed that α-LACc could improve insulin resistance-associated glucose metabolism and insulin sensitivity disorders caused by obesity. This work has developed a novel one-step purification process of α-LACc from camel whey without the use of organic solvents. Our purified α-LACc may serve as a promising therapeutic agent in the treatment of obesity-related metabolic disorders by synergistically alleviating lipid accumulation, inflammation, oxidative stress and insulin sensitivity.

Metabolic dysfunction-associated steatotic liver disease is associated with increased risks of heart failure

AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD), defined by steatotic liver disease (SLD) and cardiometabolic factors, is increasing in prevalence, but its association with heart failure (HF) is unclear.

METHODS AND RESULTS

Patients with SLD without a history of HF from 2006 to 2021 were retrospectively included and were classified into MASLD and non-MASLD groups that were followed longitudinally. The primary outcome was the new development of HF, which was sub-classified by echocardiography. Multivariable and propensity score matching analyses were conducted to adjust for confounding factors. Overall, 26 676 patients with SLD were included, with a median age of 51 years and 71% classified as MASLD. During a median follow-up of 6 years, 429 (1.61%) patients developed HF, and 76% were HF with preserved ejection fraction (HFpEF). The risk of HF was significantly higher in patients with MASLD than in those without (sub-distribution hazard ratio [SHR] 2.59, 95% confidence interval [CI] 1.84-3.64) after adjustment of competing mortality. There was a dose-dependent increase in HF risks in patients with more cardiometabolic risk factors (SHR 1.12, 95% CI 1.04-1.22). MASLD was also associated with higher risk of HF-related hospitalization (SHR 2.30, 95% CI 1.31-4.04) and specifically, the risk of HFpEF (SHR 1.91, 95% CI 1.27-2.86). In propensity score-matched cohorts, MASLD was also associated with a 2.52-fold higher risk of HF.

CONCLUSION

In patients with SLD, those with MASLD show a higher risk of HF, specifically HFpEF. Future studies are warranted to validate the association between HF and MASLD.

Haloacetamides exacerbate non-alcoholic fatty liver disease induced by a high-fat diet in C57BL/6J mice

Obesity, a significant global health issue, heightens the risk of non-alcoholic fatty liver disease (NAFLD). Its interaction with environmental pollutants might exacerbate NAFLD's severity. Haloacetamides (HAcAms), a group of emerging nitrogenous disinfection byproducts (DBPs) and potent oxidative stressors, are found in chlorinated drinking water. Since oxidative stress is associated with HAcAms-DBP cytotoxicity and a key factor in NAFLD pathogenesis, we hypothesize that HAcAms-DBPs could exacerbate liver injury and NAFLD, particularly with high-fat diets. This study examined HAcAms-DBPs' impact on liver lipid metabolism in mice treated with 1 to 100 times the background drinking water level (13.05 µg/L) for up to 16 weeks of oral administration. Compared to a high-fat-only group, mice co-exposed to a high-fat diet and HAcAms-DBPs for 16 weeks had elevated serum alanine transaminase, aspartate transaminase, triglyceride, hepatic lipid aggregation, and inflammation response. Under high-fat conditions, background drinking water levels of HAcAms significantly upregulated liver Acetyl-CoA carboxylase 1, fatty acid synthase, peroxisome proliferator-activated receptor gamma (PPARγ), PPARγ coactivator-1α, glucose transporter 1 and 4 protein expression in C57BL/6J mice; 10 times background significantly increased expression of inflammatory marker tumor necrosis factor and liver fibrosis marker protein alpha-smooth muscle actin; 100 times further increased both liver damage and markers of early non-alcoholic steatohepatitis phenotypes like steatosis and lobular inflammation. HAcAms-DBPs plus high-fat conditions worsened liver damage. The possible health risks of NAFLD induced by HAcAms in obese individuals deserve further study.

Exposure to Nanoplastics During Pregnancy Induces Brown Adipose Tissue Whitening in Male Offspring

BACKGROUND

Polystyrene nanoplastics (PSNPs) have been recognized as emerging environmental pollutants with potential health impacts, particularly on metabolic disorders. However, the mechanism by which gestational exposure to PSNPs induces obesity in offspring remains unclear. This study, focused on the whitening of brown adipose tissue (BAT), aims to elucidate the fundamental mechanisms by which prenatal exposure to PSNPs promotes obesity development in mouse offspring.

METHODS AND RESULTS

Pregnant dams were subjected to various doses of PSNPs (0 µg/µL, 0.5 µg/µL, and 1 µg/µL), and their offspring were analyzed for alterations in body weight, adipose tissue morphology, thermogenesis, adipogenesis, and lipophagy. The findings revealed a notable reduction in birth weight and an increase in white adipocyte size in adult offspring mice. Notably, adult male mice exhibited BAT whitening, correlated with a negative dose-dependent downregulation of UCP1 expression, indicating thermogenesis dysfunction. Further investigation revealed augmented lipogenesis evidenced by the upregulation of FASN, SREBP-1c, CD36, and DGAT2 expression, coupled with the inhibition of lipophagy, indicated by elevated levels of mTOR, AKT, and p62 proteins and reduced levels of LC3II/LCI and Lamp2 proteins in male offspring.

CONCLUSIONS

These findings indicate that gestational PSNP exposure plays a role in the development of obesity in offspring through the whitening of brown adipose tissue, which is triggered by lipogenesis and lipophagy inhibition, providing a novel insight into the metabolic risks associated with gestational PSNPs exposure.

The association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and hepatic steatosis and liver fibrosis among US adults based on NHANES

Recently, the non-high-density to high-density lipoprotein cholesterol ratio (NHHR) has gained growing attention as an indicator for predicting diseases associated with lipid metabolism. Hepatic steatosis and fibrosis are tightly associated lipid metabolism. Our study aims to analyze the correlations among NHHR, hepatic steatosis, and fibrosis. This study analysed data from 14,578 adults in the US National Health and Nutrition Examination Survey (2005-2018). The degree of hepatic steatosis was measured through the Fatty Liver Index (FLI), while liver fibrosis severity was evaluated with the Fibrosis-4 (FIB-4) index. Multivariate linear regression assessed the association between NHHR and the FLI and FIB-4 score. Smooth curve describing the relationship between NHHR and FLI or FIB-4. Additionally, a two-part linear regression model adopted in order to more accurately account for the nonlinear relationship, with threshold effects estimated through its two components. To confirm the robustness of the findings, interaction tests and subgroup analyses were conducted. The multivariate logistic regression analysis demonstrated a significantly positive correlation of lnNHHR with FLI across all three models. In Model 3, the association was (β = 11.14, 95%CI:10.38,11.90). Curve fitting indicated a nonlinear relationship. The positive correlation between lnNHHR and FLI persists across gender, BMI, and physical activity groups. Nevertheless, a notable negative correlation between lnNHHR and FIB-4 was observed in all three models. In Model 3, the relationship between lnNHHR and FIB-4 was as follows: (β = -0.20; 95% CI: -0.22, -0.17). Curve fitting revealed a V-shaped relationship, with threshold effect analysis identifying a breakpoint at 1.51. Above this threshold, the relationship was found to be statistically insignificant (p-value = 0.424). Receiver operating characteristic (ROC) curve analysis demonstrated that NHHR exhibited better predictive performance for MASLD compared to non-HDL-C, HDL-C, and LDL-C/HDL-C. The current study's findings suggest that elevated levels of NHHR correlate with a greater risk of hepatic steatosis among adults in the U.S. Our findings imply that NHHR may be a valuable tool in improving MASLD prevention strategies in the general population.

METTL3 promotes the progression of non-alcoholic fatty liver disease by mediating m6A methylation of FAS

N6-methyladenosine (m6A) is involved in the development of non-alcoholic fatty liver disease (NAFLD). Here, we aimed to investigate the effect of m6A methyltransferase METTL3 on liver damage in high-fat diet (HFD)-induced mouse model and hepatocyte damage treated with free fatty acid (FFA). Plasma lipid, lipogenesis, viability, and apoptosis were measured to assess injury. m6A methylation was evaluated using m6A dot blot, methylated RNA immunoprecipitation, dual-luciferase reporter assay, and RNA decay assay. The results indicated that METTL3 was highly expressed in the liver of HFD mice, which knockdown improved plasma lipid and reduced liver lipids. Additionally, silencing of METTL3 promoted cell viability, inhibited apoptosis, reduced lipid concentrations, and downregulated lipogenesis-related marker levels. Moreover, METTL3 promoted the m6A methylation of FAS and enhanced its stability. In conclusion, silencing of METTL3 attenuates the progression of NAFLD by FAS m6A methylation, suggesting that METTL3 may be a promising target for treating NAFLD.

Remnant cholesterol, a potential risk factor of metabolic dysfunction-associated fatty liver disease

OBJECTIVES

This study aimed to explore the association between remnant cholesterol and metabolic dysfunction-associated fatty liver disease (MAFLD) in an adult population in the United States.

METHODS

Data were collected from the National Health and Nutrition Examination Survey database during 2017-2020. Weighted multivariable logistic regression analyses and receiver operating characteristic (ROC) curves were used to investigate the association between remnant cholesterol and the risk of MAFLD. Subgroup and interaction analyses were performed. To further investigate the possible non-linear relationship between remnant cholesterol and MAFLD, a restricted cubic spline was used.

RESULTS

Among the included 3633 participants, the prevalence rate of MAFLD was 34.56%. After full adjustment, higher remnant cholesterol was associated with the risk of MAFLD (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.01-1.06; P = 0.02), and compared with the lowest quartile of remnant cholesterol, the highest quartile of remnant cholesterol was more likely to be associated with MAFLD (OR, 3.70; 95%CI, 2.37,5.76; P < 0.0001). A non-linear relationship between remnant cholesterol and MAFLD was found in the restricted cubic spline regression model, suggesting that the risk of MAFLD initially increased rapidly and then gradually slowed down.

CONCLUSION

Remnant cholesterol was identified as a potential risk factor for MAFLD, and a non-linear relationship between remnant cholesterol and the prevalence of MAFLD was detected. Large-scale, high-quality prospective studies are required to validate these findings.

Genetic and metabolic characterization of individual differences in liver fat accumulation in Atlantic salmon

Introduction

Lipid accumulation in the liver can negatively impact liver function and health, which is well-described for humans and other mammals, but relatively unexplored in Atlantic salmon. This study investigates the phenotypic, genetic, and transcriptomic variations related to individual differences in liver fat content within a group of slaughter-sized Atlantic salmon reared under the same conditions and fed the same feed. The objective was to increase the knowledge on liver fat deposition in farmed salmon and evaluate the potential for genetic improvement of this trait.

Methods

The study involved measuring liver fat content in a group of slaughter-sized Atlantic salmon. Genetic analysis included estimating heritability and conducting genome-wide association studies (GWAS) to identify quantitative trait loci (QTLs). Transcriptomic analysis was performed to link liver fat content to gene expression, focusing on genes involved in lipid metabolic processes.

Results

There was a large variation in liver fat content, ranging from 3.6% to 18.8%, with frequent occurrences of high liver fat. Livers with higher levels of fat had higher proportions of the fatty acids 16:1 n-7, 18:2 n-6, and 18:1 n-9, and less of the long-chain omega-3 fatty acids. The heritability of liver fat was estimated at 0.38, and the genetic coefficient of variation was 20%, indicating substantial potential for selective breeding to reduce liver fat deposition in Atlantic salmon. Liver fat deposition appears to be a polygenic trait, with no large QTLs detected by GWAS. Gene expression analysis linked liver fat content to numerous genes involved in lipid metabolic processes, including key transcription factors such as LXR, SREBP1, and ChREBP.

Discussion

The results indicated a connection between liver fat and increased cholesterol synthesis in Atlantic salmon, with potentially harmful free cholesterol accumulation. Further, the gene expression results linked liver fat accumulation to reduced peroxisomal β-oxidation, increased conversion of carbohydrates to lipids, altered phospholipid synthesis, and possibly increased de novo lipogenesis. It is undetermined whether these outcomes are due to high fat levels or if they are caused by underlying metabolic differences that result in higher liver fat levels in certain individuals. Nonetheless, the results provide new insights into the metabolic profile of livers in fish with inherent differences in liver fat content.

Remnant cholesterol and its variability independent of low density lipoprotein cholesterol predict metabolic dysfunction associated steatotic liver disease

This study aimed to determine whether remnant cholesterol (RC) and its variability can predict the onset of metabolic dysfunction-associated steatotic liver disease (MASLD) independently of low-density lipoprotein cholesterol (LDL-C) levels. A longitudinal cohort study involving 43,065 participants who underwent at least two physical examinations was conducted. This study used Cox proportional hazards models to assess the relationships among RC quartile levels (Q1-Q4), visit-to-visit variability, and the risk of MASLD. This variability was quantified using several metrics: standard deviation (SD), logSD, average real variability (ARV), logARV, mean absolute deviation (MAD), and logMAD. Concurrently, this study utilized a combined analysis of RC and LDL-C groups to assess the independent risk of MASLD associated with RC. During a mean visit-to-visit of 3.19 years (SD 2.06 years), 8374 patients (19.45%) developed MASLD. Compared with Q1, Q4 was associated with a significantly greater risk of MASLD (hazard ratio [HR] 1.309, 95% confidence interval [CI] 1.220-1.403, P < 0.001). The fully adjusted Cox model revealed that the HRs of SD, logSD, ARV, logARV, MAD and logMAD were 1.400 (95% CI 1.305-1.502), 1.278 (95% CI 1.188-1.374), 1.152 (95% CI 1.079-1.229), 1.183 (95% CI 1.140-1.227), 1.578 (95% CI 1.433-1.737) and 1.263 (95% CI 1.175-1.358), respectively. In both LDL-C subgroups (≥ 3.4 mmol/L and < 3.4 mmol/L), high baseline RC was associated with elevated MASLD risk (HR 1.208, 95% CI 1.148-1.270, P < 0.001; HR 1.246, 95% CI 1.129-1.374, P < 0.001). RC levels were independently associated with MASLD in healthy individuals, irrespective of LDL-C level. The variability of RC during visit-to-visit periods provides a predictive marker for identifying individuals at heightened risk of MASLD.