Central Obesity is an Independent Determinant of Advanced Fibrosis in Lean Patients With Nonalcoholic Fatty Liver Disease.

Background: The current definition of lean is based on body mass index (BMI). However, BMI is an imperfect surrogate for adiposity and provides no information on central obesity (CO). Hence, we explored the differences in clinical profile and liver disease severity in lean patients with nonalcoholic fatty liver disease (NAFLD) with and without CO. Methods: One hundred seventy lean patients with NAFLD (BMI <23 kg/m2) were divided into two groups depending upon the presence or absence of CO (waist circumference ≥80 cm in females and ≥90 cm in males). Noninvasive assessment of steatosis was done by ultrasound and controlled attenuation parameter (CAP), while fibrosis was assessed with FIB-4 and liver stiffness measurement (LSM). FibroScan-AST (FAST) score was used for non-invasive prediction of NASH with significant fibrosis. Results: Of 170 patients with lean NAFLD, 96 (56.5%) had CO. Female gender (40.6% vs. 17.6%, P = 0.001), hypertriglyceridemia (58.3% vs. 39.2%, P = 0.01) and metabolic syndrome (23.9% vs. 4.1%, P < 0.001) were more common in the CO group. There was a poor correlation between BMI and waist circumference (r = 0.24, 95% CI: 0.09-0.38). Grade 2-3 steatosis on ultrasound was significantly more common in CO patients (30% vs. 12.3%, P = 0.007). CAP [312.5 (289.8-341) dB/m vs. 275 (248-305.1) dB/m, P = 0.002], FAST score [0.42 (0.15-0.66) vs. 0.26 (0.11-0.39), P = 0.04], FIB-4 and LSM were higher in those with CO. Advanced fibrosis was more prevalent among CO patients using FIB-4 (19.8% vs 8.1%, P = 0.03) and LSM (9.5% vs. 0, P = 0.04). CO was independently associated with advanced fibrosis after adjusting for BMI and metabolic risk factors (aOR: 3.11 (1.10-8.96), P = 0.03). Among these 170 patients, 142 fulfilled metabolic dysfunction associated steatotic liver disease (MASLD) criteria. CO was also an independent risk factor for advanced fibrosis in MASLD (3.32 (1.23-8.5), P = 0.02). Conclusion: Lean patients with NAFLD or MASLD and CO have more severe liver disease compared to those without CO.

Visceral Fat and Diabetes: Associations With Liver Fibrosis in Metabolic Dysfunction-Associated Steatotic Liver Disease.

Background: The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, is increasing globally. Noninvasive methods, such as bioelectrical impedance analysis (BIA), which measures body composition, including visceral fat, are gaining interest in evaluating MASLD patients. Our study aimed to identify factors associated with significant liver fibrosis, compare noninvasive scores, and highlight the importance of visceral fat measurement using BIA. Methods: MASLD patients seen in our out-patient department underwent comprehensive evaluations, including liver stiffness using transient elastography, body composition analysis using BIA, and metabolic measurements. Significant fibrosis was defined as a liver stiffness measurement of ≥8.2 kPa. Using multivariate analysis, we identified factors associated with significant liver fibrosis and compared four noninvasive scores with a novel diabetes-visceral fat 15 (DVF15) score. Results: We analyzed data from 609 MASLD patients seen between February 2022 and March 2023. The median age was 43 years (81% male). Among these, 78 (13%) had significant fibrosis. Patients with significant fibrosis had higher rates of type 2 diabetes (41% vs 21%, P < 0.001) and elevated levels of aspartate aminotransferase, alanine aminotransferase, hemoglobin A1c, Fibosis-4, aspartate-aminotransferase-to platelet-ratio index, and NAFLD fibrosis scores. They also exhibited higher visceral and subcutaneous fat. Binary logistic regression revealed type 2 diabetes and a visceral fat level of >15% as associated with significant liver fibrosis. Additionally, the DVF15 score, combining these factors, showed a modest area under the receiver operating characteristic curve of 0.664 (P < 0.001). Conclusion: Our study identified diabetes and high visceral fat as factors associated with significant liver fibrosis in MASLD patients. We recommend that visceral fat measurement using BIA be an essential part of MASLD evaluation. The presence of either diabetes or a visceral fat level of >15% should prompt clinicians to check for significant fibrosis in MASLD patients. Further research is warranted to validate our findings and evaluate the utility of the DVF15 score in larger cohorts and diverse populations.

Serum folate levels and risk of metabolic dysfunction-associated steatotic liver disease: results from a cross-sectional study and Mendelian randomization analysis.

Background: Evidence from observational studies on the association between folate and metabolic dysfunction-associated steatotic liver disease (MASLD) is conflicting. Aims: This study aimed to investigate the association between serum folate concentration and MASLD and further assess the causal relationship using Mendelian randomization (MR) analysis. Methods: To investigate the causal relationship between serum folate and MASLD, we conducted a cross-sectional study that selected 1,117 participants from the 2017-2020 National Health and Nutrition Examination Survey (NHANES). The association between serum folate level and the risk of MASLD was evaluated under a multivariate logistic regression model. In addition, we conducted a two-sample MR study using genetic data from a large genome-wide association study (GWAS) to compare serum folate level (37,465 individuals) and MASLD (primary analysis: 8,434 cases/770,180 controls; Secondary analysis:1,483 cases/17,781 controls) were performed to infer causal relationships between them. Inverse variance weighted (IVW) was used as the primary method of MR Analysis. Results: The results from the NHANES database showed that Tertile 3 group (Tertile 3: ≥ 48.6 nmol/L) had a significantly lower risk (OR = 0.58, 95% CI: 0.38-0.88, p = 0.010) of MASLD than Tertile 1 group (Tertile 1: < 22.3 nmol/L) after complete adjustments. However, in the IVW of MR analysis, there was no causal relationship between serum folate level and MASLD risk in the primary analysis (OR = 0.75, 95% CI: 0.55-1.02, p = 0.065) and secondary analysis (OR = 0.83, 95% CI: 0.39-1.74, p = 0.618). Conclusion: In observational analyses, we observed an inverse association between higher serum folate concentrations and a reduced risk of MASLD. Our MR study generated similar results, but the association failed to reach the significance threshold of p < 0.05, suggesting that our MR study does not support a causal relationship between serum folate levels and MASLD risk. Additional research involving a larger number of cases would contribute to enhancing the confirmation of our preliminary findings.

Metabolic-associated steatotic liver disease and risk of Alzheimer's disease: a real-world retrospective cohort study.

Objective: Alzheimer's Disease (AD) is increasingly recognized as being associated with metabolic disorders, including Metabolic Associated Steatotic Liver Disease (MASLD). This study aimed to assess the relative risk of AD in individuals with MASLD. Methods: In this retrospective cohort study, we analyzed data from individuals aged over 65 who underwent health check-ups between January 2018 and June 2023. MASLD was diagnosed based on ultrasound findings and cardiometabolic criteria. AD incidence was identified using ICD-10 codes and self-reports. Poisson regression models estimated the relative risk of AD in relation to MASLD, adjusting for age, BMI, sex, SBP, HbA1c, HDL-c, triglycerides, hs-CRP, GGT, and estimated GFR. Results: The study included 4,582 MASLD patients and 6,318 controls. MASLD patients showed a higher incidence of AD (127 cases) compared to controls (61 cases). The fully adjusted Poisson regression model indicated an increased AD risk in MASLD patients [RR: 2.80 (95% CI: 1.79-4.38)]. Conclusion: Our findings suggested MASLD as an independent risk factor for AD, underlining the role of metabolic dysfunctions in AD pathogenesis. The study emphasized the need for comprehensive metabolic health management in AD prevention strategies, particularly among high-risk groups.

IL-22 resolves MASLD via enterocyte STAT3 restoration of diet-perturbed intestinal homeostasis.

The exponential rise in metabolic dysfunction-associated steatotic liver disease (MASLD) parallels the ever-increasing consumption of energy-dense diets, underscoring the need for effective MASLD-resolving drugs. MASLD pathogenesis is linked to obesity, diabetes, "gut-liver axis" alterations, and defective interleukin-22 (IL-22) signaling. Although barrier-protective IL-22 blunts diet-induced metabolic alterations, inhibits lipid intake, and reverses microbial dysbiosis, obesogenic diets rapidly suppress its production by small intestine-localized innate lymphocytes. This results in STAT3 inhibition in intestinal epithelial cells (IECs) and expansion of the absorptive enterocyte compartment. These MASLD-sustaining aberrations were reversed by administration of recombinant IL-22, which resolved hepatosteatosis, inflammation, fibrosis, and insulin resistance. Exogenous IL-22 exerted its therapeutic effects through its IEC receptor, rather than hepatocytes, activating STAT3 and inhibiting WNT-ß-catenin signaling to shrink the absorptive enterocyte compartment. By reversing diet-reinforced macronutrient absorption, the main source of liver lipids, IL-22 signaling restoration represents a potentially effective interception of dietary obesity and MASLD.

Ceramide synthesis inhibitors prevent lipid-induced insulin resistance through the DAG-PKCε-insulin receptorT1150 phosphorylation pathway.

Inhibition of the ceramide synthetic pathway with myriocin or an antisense oligonucleotide (ASO) targeting dihydroceramide desaturase (DES1) both improved hepatic insulin sensitivity in rats fed either a saturated or unsaturated fat diet and was associated with reductions in both hepatic ceramide and plasma membrane (PM)-sn-1,2-diacylglycerol (DAG) content. The insulin sensitizing effects of myriocin and Des1 ASO were abrogated by acute treatment with an ASO against DGAT2, which increased hepatic PM-sn-1,2-DAG but not hepatic C16 ceramide content. Increased PM-sn-1,2-DAG content was associated with protein kinase C (PKC)ε activation, increased insulin receptor (INSR)T1150 phosphorylation leading to reduced insulin-stimulated INSRY1152/AktS473 phosphorylation, and impaired insulin-mediated suppression of endogenous glucose production. These results demonstrate that inhibition of de novo ceramide synthesis by either myriocin treatment or DES1 knockdown protects against lipid-induced hepatic insulin resistance through a C16 ceramide-independent mechanism and that they mediate their effects to protect from lipid-induced hepatic insulin resistance via the PM-sn-1,2-DAG-PKCε-INSRT1150 phosphorylation pathway.

NOVEL EICOSANOID SIGNATURE IN PLASMA PROVIDES DIAGNOSTIC FOR METABOLIC DYSFUNCTION-ASSOCIATED STEATOTIC LIVER DISEASE.

There is a clinical need for a simple test implementable at the primary point of care to identify individuals with metabolic dysfunction-associated steatotic liver disease (MASLD) in the population. Blood plasma samples from adult patients with varying phenotypes of MASLD were used to identify a minimal set of lipid analytes reflective of underlying histologically confirmed MASLD. Samples were obtained from the NIDDK Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN) NAFLD Database prospective cohort study (MASLD group; N = 301). Samples of control subjects were obtained from cohort studies at the University of California San Diego (control group; N = 48). Plasma samples were utilized for targeted quantitation of circulating eicosanoids, related bioactive metabolites, and polyunsaturated fatty acids by ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) lipidomics analysis. Bioinformatic approaches were used to discover a panel of bioactive lipids that can be used as a diagnostic tool to identify MASLD. The final panel of fifteen lipid metabolites consists of 12 eicosanoid metabolites and 3 free fatty acids that were identified to be predictive for MASLD by multivariate area under the receiver operating characteristics curve (AUROC) analysis. The panel was highly predictive for MASLD with an AUROC of 0.999 (95% CI = 0.986-1.0) with only one control misclassified. While a validation study is included, a prospective larger scale study with matched controls will be required to optimize the resulting MASLD LIPIDOMICS SCORE to become a non-invasive "point-of-care" test to identify MASLD patients requiring further evaluation for the presence of metabolic dysfunction-associated steatohepatitis (MASH).

Myeloid beta-arrestin 2 depletion attenuates metabolic dysfunction-associated steatohepatitis via the metabolic reprogramming of macrophages.

Macrophage-mediated inflammation has been implicated in the pathogenesis of metabolic dysfunction-associated steatohepatitis (MASH); however, the immunometabolic program underlying the regulation of macrophage activation remains unclear. Beta-arrestin 2, a multifunctional adaptor protein, is highly expressed in bone marrow tissues and macrophages and is involved in metabolism disorders. Here, we observed that ß-arrestin 2 expression was significantly increased in the liver macrophages and circulating monocytes of patients with MASH compared with healthy controls and positively correlated with the severity of metabolic dysfunction-associated steatotic liver disease (MASLD). Global or myeloid Arrb2 deficiency prevented the development of MASH in mice. Further study showed that ß-arrestin 2 acted as an adaptor protein and promoted ubiquitination of immune responsive gene 1 (IRG1) to prevent increased itaconate production in macrophages, which resulted in enhanced succinate dehydrogenase activity, thereby promoting the release of mitochondrial reactive oxygen species and M1 polarization. Myeloid ß-arrestin 2 depletion may be a potential approach for MASH.

Quantitative MRI for Monitoring Metabolic Dysfunction-Associated Steatotic Liver Disease: A Test-Retest Repeatability Study.

BACKGROUND: Quantitative magnetic resonance imaging metrics iron-corrected T1 (cT1) and liver fat from proton density fat-fraction (PDFF) are both commonly used as noninvasive biomarkers for metabolic dysfunction-associated steatohepatitis (MASH); however, their repeatability in this population has rarely been characterized. PURPOSE: To quantify the variability of cT1 and liver fat fraction from PDFF in patients with biopsy-confirmed metabolic dysfunction-associated steatotic liver disease (MASLD) and MASH. STUDY TYPE: Prospective, single center. POPULATION: Twenty-one participants (female = 11, mean age 53 ± 24 years) with biopsy-confirmed MASLD, including 6 with MASH and fibrosis ≥2. FIELD STRENGTH/SEQUENCE: 3 T; T1 and T2* mapping for the generation of cT1 (shMOLLI: CardioMaps and 2D MDE, T1map-FIESTA and LMS MOST: StarMap, 2D Multi-Echo FSPGR) and magnitude-only PDFF sequence for liver fat quantification (LMS IDEAL: StarMap, 2D Multi-Echo FSPGR). ASSESSMENT: T1 mapping and PDFF scans were performed twice on the same day for all participants (N = 21), with an additional scan 2-4 weeks later for MASH patients with fibrosis ≥2 (N = 6). Whole liver segmentation masks were generated semi-automatically and average pixel counts within these masks were used for the calculation of cT1 and liver fat fraction. STATISTICAL TESTS: Bland-Altman analysis for repeatability coefficient (RC) and 95% limits of agreement (LOA) and intraclass correlation coefficient (ICC). RESULTS: Same-day RC was 32.1 msec (95% LOA: -36.6 to 24.2 msec) for cT1 and 0.6% (95% LOA: -0.5% to 0.7%) for liver fat fraction; the ICCs were 0.98 (0.96-0.99) and 1.0, respectively. Short-term RC was 65.2 msec (95% LOA: -63.8 to 76.5 msec) for cT1 and 2.6% (95% LOA: -2.8% to 3.1%) for liver fat fraction. DATA CONCLUSION: In participants with MASLD and MASH, cT1 and liver fat fraction measurements show excellent test-retest repeatability, supporting their use in monitoring MASLD and MASH. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

Characterizing outcomes in a large cohort of latinx patients with autoimmune hepatitis.

INTRODUCTION AND OBJECTIVES: This study aimed to characterize a large cohort of Latinx patients with autoimmune hepatitis (AIH) and analyze clinical outcomes, including biochemical remission, duration of steroid treatment, fibrosis regression, and incidence of clinical endpoints (hepatic decompensation, need for liver transplant, and death). MATERIALS AND METHODS: This was a retrospective descriptive study of patients with biopsy proven AIH (2009-2019) at a single urban center. Demographics, medical comorbidities, histology, treatment course, biochemical markers, fibrosis using dynamic non-invasive testing (NIT), and clinical outcomes at three months and at one, two, and three years were analyzed. RESULTS: 121 adult patients with biopsy-proven AIH were included: 43 Latinx (35.5%) and 78 non-Latinx (65.5%). Latinx patients were more likely to have metabolic dysfunction-associated steatotic liver disease (MASLD) (p = 0.004), and had higher Fibrosis-4 (FIB-4) (p = 0.0279) and AST-to-Platelet-Ratio-Index (APRI) (p = 0.005) at one year. Latinx patients took longer to reach biochemical remission than non-Hispanic Whites (p = 0.031) and longer to stop steroids than non-Hispanic Blacks (p = 0.016). There were no significant differences based on ethnicity in histological fibrosis stage at presentation or incidence of clinical endpoints. CONCLUSIONS: MASLD overlap is highly prevalent in Latinx AIH patients. Longer time to biochemical remission and worse NITs support that this population may have slower fibrosis regression with standard of care AIH treatment. This may indicate differing response rates due to genetic polymorphisms affecting drug metabolism and immune response among Latinx individuals and is less likely related to AIH/MASLD overlap based on the findings of this study.

Extracellular Vesicles as a potential source of biomarkers for endocrine disruptors in MASLD: a short review on the case of DEHP.

Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD) is a chronic disease with increasing prevalence and for which non-invasive biomarkers are needed. Environmental endocrine disruptors (EDs) are known to be involved in the onset and progression of MASLD and assays to monitor their impact on the liver are being developed. Extracellular vesicles (EVs) mediate cell communication and their content reflects the pathophysiological state of the cells from which they are released. They can thus serve as biomarkers of the pathological state of the liver and of exposure to EDs. In this review, we present the relationships between DEHP (Di(2-ethylhexyl) phthalate) and MASLD and highlight the potential of EVs as biomarkers of DEHP exposure and the resulting progression of MASLD.

Impairment of health-related quality of life among people with type 2 diabetes and advanced liver fibrosis.

People with type 2 diabetes mellitus (T2DM) show a high prevalence of steatotic liver disease (SLD), and especially metabolic dysfunction-associated steatotic liver disease (MASLD), with liver fibrosis. Their health-related quality of life (HRQL) is affected by multiple in part overlapping factors and aggravated by metabolic and liver-related comorbidities, including liver fibrosis stage. The aim of this study was to investigate the effect size of advanced fibrosis (AF) on the HRQL in people with T2DM. A total of 149 individuals with T2DM treated at a primary care provider within the German disease management program (DMP) were included in the final analysis. Vibration-controlled transient elastography (VCTE) was used to non-invasively detect steatosis and AF. The EQ-5D-3L questionnaire was used to assess the HRQL. Uni- and multivariable linear regression models were used to identify independent predictors of impaired HRQL. The majority was male (63.1%), and the median age was 67 years (IQR 59; 71). In the entire cohort, the prevalence of MASLD and AF was 70.7% and 19.5%, respectively. People with T2DM and AF had an overall lower HRQL in comparison to those without AF (p < 0.001). Obesity (ß: - 0.247; 95% CI - 0.419, - 0.077) and AF (ß: - 0.222; 95% CI - 0.383, - 0.051) remained independent predictors of a poor HRQL. In turn, T2DM-related comorbidities were not predictive of an impaired HRQL. Obesity and AF negatively affect the HRQL in patients with SLD and T2DM in primary care. Awareness of liver health and specific interventions may improve patient-reported and liver-related outcomes in people with T2DM.

Natural Linoleic Acid from Marine Fungus Eutypella sp. F0219 Blocks KEAP1/NRF2 Interaction and Ameliorates MASLD by Targeting FABP4.

Ectopic lipid accumulation induced lipotoxicity plays a crucial role in exacerbating the development of metabolic dysfunction-associated steatotic liver disease (MASLD), which affects over 30% of the worldwide population and 85% of the obese population. The growing demand for effective therapeutic agents highlights the need for high-efficacy lipotoxicity ameliorators and relevant therapeutic targets in the fight against MASLD. This study aimed to discover natural anti-lipotoxic and anti-MASLD candidates and elucidate the underlying mechanism and therapeutic targets. Utilizing palmitic acid (PA)-induced HepG-2 and primary mouse hepatocyte models, we identified linoleic acid (HN-002), a ligand of fatty acid binding protein 4 (FABP4), from the marine fungus Eutypella sp. F0219. HN-002 dose-dependently prevented lipid overload-induced hepatocyte damage and lipid accumulation, inhibited fatty acid esterification, and ameliorated oxidative stress. These beneficial effects were associated with improvements in mitochondrial adaptive oxidation. HN-002 treatment enhanced lipid transport into mitochondria and oxidation, inhibited mitochondrial depolarization, and reduced mitochondrial ROS (mtROS) level in PA-treated hepatocytes. Mechanistically, HN-002 treatment disrupted the interaction between KEAP1 and NRF2, leading to NRF2 deubiquitylation and nuclear translocation, which activated beneficial metabolic regulation. In vivo, HN-002 treatment (20 mg/kg/per 2 days, i. p.) for 25 days effectively reversed hepatic steatosis and liver injury in the fast/refeeding plus high-fat/high-cholesterol diet induced MASLD mice. These therapeutic effects were associated with enhanced mitochondrial adaptive oxidation and activation of NRF2 signaling in the liver. These data suggest that HN-002 would be an interesting candidate for MASLD by improving mitochondrial oxidation via the FABP4/KEAP1/NRF2 axis. The discovery offers new insights into developing novel anti- MASLD agents derived from marine sources.

Effect of Pemafibrate on the Lipid Profile, Liver Function, and Liver Fibrosis Among Patients With Metabolic Dysfunction-Associated Steatotic Liver Disease.

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are prevalent conditions linked to obesity and metabolic disturbances, with potential complications such as cirrhosis and cardiovascular risks. This systematic review and meta-analysis aimed to evaluate the efficacy of pemafibrate, a drug targeting fat and sugar metabolism genes, in treating patients with MASLD/MASH. Methods: Databases such as MEDLINE, Web of Science, Cochrane Library, and Scopus were searched until September 2023 to identify relevant studies. Selected studies underwent a thorough quality assessment using tools like Risk of Bias 2 tool (ROB-2) and the National Institutes of Health (NIH) Quality Assessment Tools. Comprehensive meta-analysis software was used for statistical evaluations, with a focus on lipid profiles, liver function tests, and fibrosis measurements. Results: A total of 13 studies were included; 10 of them were included in the quantitative analysis. Our findings showed that pemafibrate significantly decreased low-density lipoprotein cholesterol (LDL-C) (effect size (ES) = -9.61 mg/dL, 95% confidence interval (CI): -14.15 to -5.08), increased high-density lipoprotein cholesterol (HDL-C) (ES = 3.15 mg/dL, 95% CI: 1.53 to 4.78), and reduced triglycerides (TG) (ES = -85.98 mg/dL, 95% CI: -96.61 to -75.36). Additionally, pemafibrate showed a marked reduction in liver enzyme levels, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyl transpeptidase (GGT), and alkaline phosphatase (ALP), with significant effect sizes and P values. For liver stiffness outcomes, pemafibrate decreased AST to platelet ratio index (APRI) (ES = -0.180, 95% CI: -0.221 to -0.138). Conclusions: Pemafibrate, with its enhanced efficacy and safety profile, presents as a pivotal agent in MASLD/MASH treatment. Its lipid-regulating properties, coupled with its beneficial effects on liver inflammation markers, position it as a potentially invaluable therapeutic option.

Multiomics analyses decipher intricate changes in the cellular and metabolic landscape of steatotic livers upon dietary restriction and sleeve gastrectomy.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a chronic, progressive liver disease that encompasses a spectrum of steatosis, steatohepatitis (or MASH), and fibrosis. Evidence suggests that dietary restriction (DR) and sleeve gastrectomy (SG) can lead to remission of hepatic steatosis and inflammation through weight loss, but it is unclear whether these procedures induce distinct metabolic or immunological changes in MASLD livers. This study aims to elucidate the intricate hepatic changes following DR, SG or sham surgery in rats fed a high-fat diet as a model of obesity-related MASLD, in comparison to a clinical cohort of patients undergoing SG. Single-cell and single-nuclei transcriptome analysis, spatial metabolomics, and immunohistochemistry revealed the liver landscape, while circulating biomarkers were measured in serum samples. Artificial intelligence (AI)-assisted image analysis characterized the spatial distribution of hepatocytes, myeloid cells and lymphocytes. In patients and experimental MASLD rats, SG improved body mass index, circulating liver injury biomarkers and triglyceride levels. Both DR and SG attenuated liver steatosis and fibrosis in rats. Metabolism-related genes (Ppara, Cyp2e1 and Cyp7a1) were upregulated in hepatocytes upon DR and SG, while SG broadly upregulated lipid metabolism on cholangiocytes, monocytes, macrophages, and neutrophils. Furthermore, SG promoted restorative myeloid cell accumulation in the liver not only ameliorating inflammation but activating liver repair processes. Regions with potent myeloid infiltration were marked with enhanced metabolic capacities upon SG. Additionally, a disruption of periportal hepatocyte functions was observed upon DR. In conclusion, this study indicates a dynamic cellular crosstalk in steatotic livers of patients undergoing SG. Notably, PPARα- and gut-liver axis-related processes, and metabolically active myeloid cell infiltration indicate intervention-related mechanisms supporting the indication of SG for the treatment of MASLD.

Targeting PYK2 with heterobifunctional T6BP helps mitigate MASLD and MASH-HCC progression.

BACKGROUND & AIMS: The mechanisms underlying the regulation of hepatocyte non-receptor tyrosine kinases in metabolic dysfunction-associated steatohepatitis (MASH) remain largely unclear. METHODS: Hepatocyte-specific overexpression or deletion and anti-protein tyrosine kinase 2 beta (PYK2) or anti-TRAF6-binding protein (T6BP) crosslinking were utilised to study fatty liver protection by T6BP. P-PTC, a peptide-proteolysis targeting chimaera, degrades PYK2 to block MASH progression. RESULTS: Since PYK2 activation is promoter signalling in steatohepatitis development, we find that T6BP is a novel and critical suppressor of PYK2 that reduces hepatic lipid accumulation, pro-inflammatory factor release, and pro-fibrosis production by ubiquitin ligase CBL to degrade PYK2. Mechanistic evidence suggests that T6BP directly targets PYK2 and prevents its N-terminal FERM domain-triggered dimerization, disrupting downstream PYK2-JNK signalling hyperactivation. Additionally, T6BP favourably recruits CBL, a particular E3 ubiquitin ligase targeting PYK2, to form a complex and degrade PYK2. T6BP (F1), a core fragment of T6BP, directly blocks N-terminal FERM domain-associated dimerization of PYK2, followed by T6BP-recruiting CBL-mediated PYK2 degradation in a typical T6BP-dependent manner when the tiny fragment is specifically expressed using thyroxine binding globulin (TBG)-ground vectors. This inhibits the progression of MASH, metabolic dysfunction-associated steatotic liver disease (MASLD)-related HCC (MASH-HCC), and metabolic syndrome in dietary rodent models. First-ever peptide-proteolysis targeting chimaera (P-PTC) based on the core segment of T6BP as a ligand for targeted recruitment of CBL targeting metabolic disorders like MASH has been devised and validated in animal models. CONCLUSIONS: Our study revealed a previously unknown mechanism: identification of T6BP as a key eliminator of fatty liver strongly contributes to the development of promising therapeutic targets, and the discovery of crucial fragments of T6BP-based pharmacon that interrupt PYK2 dimerization are novel and viable treatments for fatty liver and its advanced symptoms and complications. IMPACT AND IMPLICATIONS: Excessive high-energy diet ingestion is critical in driving steatohepatitis via regulation of hepatocyte non-receptor tyrosine kinases. The mechanisms under lying the regulation of hepatocyte PYK2 in metabolic dysfunction-associated steatohepatitis (MASH) remain largely unclear. Here, we found that T6BP as a critical fatty liver eliminator has a significant impact on the development of promising therapeutic targets. Additionally, vital T6BP-based pharmacon fragments that impede PYK2 dimerization have been found, offering new and effective treatments for advanced fatty liver symptoms and complications.

Sex-specific effects of PNPLA3 I148M.

Metabolic dysfunction-associated steatotic liver disease (MASLD, previously termed NAFLD, nonalcoholic fatty liver disease) is a complex multifactorial disease showing generally higher prevalence and severity in men than in women. With respect to women, men are also more prone to develop metabolic dysfunction-associated steatohepatitis, fibrosis and liver-related complications. Several genetic, hormonal, environmental and lifestyle factors may contribute to sex differences in MASLD development, progression and outcomes. However, after menopause, the sex-specific prevalence of MASLD shows an opposite trend between men and women, pointing to the relevance of oestrogen signalling in the sexual dimorphism of MASLD. The patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene, that encodes a triacylglycerol lipase that plays a crucial role in lipid metabolism, has emerged as a key player in the pathogenesis of MASLD, with the I148M variant being strongly associated with increased liver fat content and disease severity. Recent advances indicate that carrying the PNPLA3 I148M variant can be a risk factor for MASLD especially for women. To elucidate the molecular mechanisms underlying the sex-specific role of PNPLA3 I148M in the development of MASLD, several in vitro, ex vivo and in vivo models have been developed.

SIRT1 and FOXO1 role on MASLD risk: effects of DHA-rich n-3 PUFA supplementation and exercise in aged obese female mice and in post-menopausal overweight/obese women.

Sirtuins 1 (SIRT1) and Forkhead box protein O1 (FOXO1) expression have been associated with obesity and metabolic dysfunction-associated steatotic liver disease (MASLD). Exercise and/or docosahexaenoic acid (DHA) supplementation have shown beneficial effects on MASLD. The current study aims to assess the relationships between Sirt1, Foxo1 mRNA levels and several MASLD biomarkers, as well as the effects of DHA-rich n-3 PUFA supplementation and/or exercise in the steatotic liver of aged obese female mice, and in peripheral blood mononuclear cells (PBMCs) of postmenopausal women with overweight/obesity. In the liver of 18-month-old mice, Sirt1 levels positively correlated with the expression of genes related to fatty acid oxidation, and negatively correlated with lipogenic and proinflammatory genes. Exercise (long-term treadmill training), especially when combined with DHA, upregulated hepatic Sirt1 mRNA levels. Liver Foxo1 mRNA levels positively associated with hepatic triglycerides (TG) content and the expression of lipogenic and pro-inflammatory genes, while negatively correlated with the lipolytic gene Hsl. In PBMCs of postmenopausal women with overweight/obesity, FOXO1 mRNA expression negatively correlated with the hepatic steatosis index (HSI) and the Zhejiang University index (ZJU). After 16-weeks of DHA-rich PUFA supplementation and/or progressive resistance training (RT), most groups exhibited reduced MASLD biomarkers and risk indexes accompanying with body fat mass reduction, but no significant changes were found between the intervention groups. However, in PBMCs n-3 supplementation upregulated FOXO1 expression, and the RT groups exhibited higher SIRT1 expression. In summary, SIRT1 and FOXO1 could be involved in the beneficial mechanisms of exercise and n-3 PUFA supplementation related to MASLD manifestation.

Mediterranean diet for the management of metabolic dysfunction-associated steatotic liver disease in non-Mediterranean, Western countries: What's known and what's needed?

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common liver disease worldwide, affecting 30% of the population in Western countries. MASLD is considered the hepatic manifestation of the metabolic syndrome, pathophysiologically underpinned by insulin resistance and frequently co-exists with hypertension, central obesity and dyslipidaemia. Currently, safe and effective pharmacotherapies for MASLD are limited, making weight loss with lifestyle changes the mainstay therapy. A Mediterranean diet (MedDiet) has emerged as an effective dietary pattern for preventing and managing MASLD, but most studies have been conducted in Mediterranean countries, necessitating further investigation into its benefits in Western populations. Additionally, the effect of holistic multimodal lifestyle interventions, including physical activity combined with the MedDiet, is not well established. Finally, MASLD's widespread prevalence and rapid growth require improved accessibility to interventions. Digital health delivery platforms, designed for remote access, could be a promising approach to providing timely support to individuals with MASLD. This narrative review summarises the current evidence related to the effects of the MedDiet in Western, multicultural populations with MASLD. This includes a detailed description of the composition, prescription and adherence to dietary interventions in terms of how they have been designed and applied. The evidence related to the role of physical activity or exercise interventions prescribed in combination with the MedDiet for MASLD will also be reviewed. Finally, recommendations for the design and delivery of dietary and physical activity or exercise interventions to inform the design of future randomised controlled trials to facilitate the optimal management of MASLD are outlined.

Association between MASLD and increased risk of serious bacterial infections requiring hospital admission: A meta-analysis.

BACKGROUND: Previous studies have reported an association between metabolic dysfunction-associated steatotic liver disease (MASLD) and the risk of serious bacterial infections. However, the magnitude of the risk and whether this risk varies with the severity of MASLD remains uncertain. We performed a meta-analysis of observational studies to quantify the association between MASLD and serious bacterial infections requiring hospital admission. METHODS: We systematically searched PubMed, Scopus, Web of Science and Embase from database inception to 1 April 2024, using predefined keywords to identify studies examining the risk of serious bacterial infections among individuals with and without MASLD. MASLD was diagnosed using liver biopsy, imaging or International Classification of Diseases codes. Meta-analysis was performed using random-effects modelling. RESULTS: We identified six cross-sectional and two prospective cohort studies with aggregate data on ~26.6 million individuals. MASLD was significantly associated with higher odds of serious bacterial infections (pooled random-effects odds ratio 1.93, 95% confidence interval [CI] 1.44-2.58; I2 = 93%). Meta-analysis of prospective cohort studies showed that MAFLD was associated with an increased risk of developing serious bacterial infections (pooled random-effects hazard ratio 1.80, 95% CI 1.62-2.0; I2 = 89%). This risk further increased across the severity of MASLD, especially the severity of fibrosis (pooled random-effects hazard ratio 2.42, 95% CI 1.89-2.29; I2 = 92%). These results remained significant after adjusting for age, sex, obesity, diabetes and other potential confounders. Sensitivity analyses did not modify these findings. The funnel plot did not reveal any significant publication bias. CONCLUSIONS: This meta-analysis shows a significant association between MASLD and an increased risk of serious bacterial infections requiring hospital admission.