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Upadacitinib (UPA) has been utilized to treat conditions such as rheumatoid arthritis, psoriatic arthritis, atopic dermatitis, ulcerative colitis, Crohn's disease, ankylosing spondylitis, and axial spondyloarthritis by modulating inflammation via the JAK pathway. However, its impact on hepatic lipogenesis remains insufficiently studied. This research evaluated protein expression through Western blotting, lipid accumulation with oil red O staining, autophagosomes in hepatocytes via MDC staining, and hepatic apoptosis via cell viability and caspase 3 activity assays. This study aimed to explore the effects of UPA on hepatic lipogenesis and the underlying molecular mechanisms in in vitro models of hepatic steatosis. These findings demonstrated that UPA reduced lipid deposition, apoptosis, and ER stress in palmitate-treated hepatocytes. UPA treatment inhibited phosphorylated JAK1 and STAT3 while promoting the expression of phosphorylated AMPK and autophagy markers. AMPK siRNA negated the effects of UPA on lipogenic lipid deposition, apoptosis, JAK1/STAT3 phosphorylation, and ER stress. These results reveal that UPAmitigates ER stress through the JAK1/STAT3/AMPK pathway, thereby reducing lipid deposition and apoptosis in hyperlipidemic hepatocytes, supporting its potential as a therapeutic strategy for treating hepatic steatosis in obese individuals., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Lipid metabolism, particularly triglyceride (TG) metabolism, is crucial for liver regeneration. During the early phase of liver regeneration, the liver temporarily accumulates a substantial amount of TG-dominated lipids. However, the specific composition of the TG profile during this phase is not yet fully understood. Here, we showed that the TG molecular composition in the liver was significantly altered during liver regeneration following carbon tetrachloride (CCl 4 )-induced liver injury. Lipid accumulation in livers was observed as early as 12 hours after CCl 4 treatment, with transient regeneration-associated steatosis (TRAS) lasting until 24 hours. Hepatocyte proliferation began only after liver lipid levels returned to baseline at 48 hours. Furthermore, the profile of TG species changed significantly during liver regeneration. During the TRAS period, the accumulated TGs in the liver were mainly long-chain triglycerides, with most of the fatty acids constituting these triglycerides having fewer than 20 carbon atoms. In the proliferation phase, the fatty acid composition of these triglycerides shifted from long-chain to ultra-long-chain fatty acids. Our results suggest a significant TRAS-related change in the TG lipid profile of the liver during liver regeneration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

The objective of our study is to measure perirenal fat thickness using MRI in individuals with steatotic liver disease and investigate the relationship between perirenal fat thickness and metabolic syndrome. This retrospective study included consecutive patients with steatotic liver disease who underwent magnetic resonance imaging-proton density fat fraction from October 2018 to February 2020. Among them, patients with crossed fused kidneys or who underwent nephrectomy were excluded. The metabolic abnormalities were reviewed; presence of hypertension, type 2 diabetes, abdominal circumference, triglyceride, and high-density lipoprotein. Perirenal fat was measured in four directions in both kidneys and the total sum of them was calculated. A total of 250 patients (140 males and 110 females) were included. Perirenal fat thickness showed a moderate correlation with waist circumference, creatinine, and hepatic fat fraction (all p < 0.001). Perirenal fat thickness was significantly higher in patients with metabolic syndrome than in patients without (76.8 mm vs. 65.1 mm, p = 0.004). In multivariable regression analysis, the group with high perirenal fat thickness had as significantly higher odd ratio of 2.71 compared to the low group. The perirenal fat thickness is independently associated with metabolic syndrome in patients with steatotic liver disease., (© 2024. The Author(s).)

Fat accumulation, de novo lipogenesis, and glycolysis are key drivers of hepatocyte reprogramming and the consequent metabolic dysfunction-associated steatotic liver disease (MASLD). Here we report that obesity leads to dysregulated expression of hepatic protein-tyrosine phosphatases (PTPs). PTPRK was found to be increased in steatotic hepatocytes in both humans and mice, and correlates positively with PPARγ-induced lipogenic signaling. High-fat-fed PTPRK knockout male and female mice have lower weight gain and reduced hepatic fat accumulation. Phosphoproteomic analysis in primary hepatocytes and hepatic metabolomics identified fructose-1,6-bisphosphatase 1 and glycolysis as PTPRK targets in metabolic reprogramming. Mechanistically, PTPRK-induced glycolysis enhances PPARγ and lipogenesis in hepatocytes. Silencing PTPRK in liver cancer cell lines reduces colony-forming capacity and high-fat-fed PTPRK knockout mice exposed to a hepatic carcinogen develop smaller tumours. Our study defines the role of PTPRK in the regulation of hepatic glycolysis, lipid metabolism, and tumour development in obesity., (© 2024. The Author(s).)

Aims: Glycogenic hepatopathy is associated with significant psychosocial consequences and health costs. Metabolic Dysfunction-Associated Steatotic Liver Disease and glycogenic hepatopathy are frequently confused as "fatty liver" when seen on ultrasonography. We wished to examine liver fat and glycogen content in groups defined based on metabolic and liver disease phenotypes., Methods: This case-control study undertaken in a tertiary hospital used nuclear proton magnetic resonance spectroscopy ( 1 H-MRS) to examine liver fat and glycogen content in five clinical groups, each containing five participants: 1. type 1 diabetes with glycogenic hepatopathy, 2. satisfactorily controlled type 1 diabetes with no liver disease, 3. poorly controlled type 1 diabetes without liver disease, 4. a control group of body mass index- and age-matched individuals without diabetes or liver disease, and 5. hepatic steatosis., Results: Fat content was highest in the hepatic steatosis (median 15.4 %, IQR 10.0-19.3) and glycogenic hepatopathy (median 6.5 %, IQR 4.5-9.1) groups and compared to both of these groups was lower in the control group (median 1.0 %, IQR 0.7-1.1, p 0.002 and 0.022), the T1DM group with satisfactory control (median 0.3 %, IQR 0.2-0.6, p < 0.001 and <0.001), and the T1DM group with poor control without liver disease (median 1.1 %, IQR 0.9-1.1, p 0.001 and 0.012). No participants from the type 1 diabetes poor control, type 1 diabetes satisfactory control or the no diabetes groups had 1 H-MRS-diagnosed hepatic steatosis. 1 H-MRS glycogen content could not be interpreted in the majority of those with glycogenic hepatopathy because of interference from the fat signal., Conclusions: In cases diagnosed with glycogenic hepatopathy there may be significant concomitant fat accumulation, compounding the already elevated cardiovascular risk in this cohort. The technique of 1 H-MRS has not been demonstrated to be useful for diagnosing glycogenic hepatopathy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2024 Elsevier Inc. All rights reserved.)

We previously demonstrated hepatic, cardiac, and skin inflammation in a high-fat diet-induced steatotic liver disease (SLD) model. However, the molecular mechanism in the kidneys in this model remains unclear. It has been recently reported that SGLT2 inhibitors improve chronic kidney disease (CKD). Therefore, we used this model to evaluate the effects of tofogliflozin on renal lipid metabolism and inflammation. Male 8-10-week-old C57Bl/6 mice were fed a high-fat/high-cholesterol/high-sucrose/bile acid (HF/HC/HS/BA) diet with 0.015% tofogliflozin (Tofo group) or an HF/HC/HS/BA diet alone (SLD group). After eight weeks, serum lipid profiles, histology, lipid content, and mRNA/microRNA and protein expression levels in the kidney were examined. The Tofo group showed significant reductions in body (26.9 ± 0.9 vs. 24.5 ± 1.0 g; p < 0.001) and kidney weight compared to those of the SLD group. Renal cholesterol (9.1 ± 1.6 vs. 7.5 ± 0.7 mg/g; p < 0.05) and non-esterified fatty acid (NEFA) (12.0 ± 3.0 vs. 8.4 ± 1.5 μEq/g; p < 0.01) were significantly decreased in the Tofo group. Transmission electron microscopy revealed the presence of fewer lipid droplets. mRNA sequencing analysis revealed that fatty acid metabolism-related genes were upregulated and NFκB signaling pathway-related genes were downregulated in the Tofo group. MicroRNA sequencing analysis indicated that miR-21a was downregulated and miR-204 was upregulated in the Tofo group. Notably, the expression of PPARα, which has been known to be negatively regulated by miR-21, was significantly increased, leading to enhancing β-oxidation genes, Acox1 and Cpt1 in the Tofo group. Tofogliflozin decreased renal cholesterol and NEFA levels and improved inflammation through the regulation of PPARα and miR-21a.

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is common in people with HIV (PWH). The morphological spectrum of MASLD compared to matched controls and of the correlation between the NAFLD activity score (NAS) and fibrosis stage in PWH remains unknown., Methods: Overall, 107 liver biopsies from PWH with MASLD (MASLD-PWH) were matched to 107 biopsies from individuals with MASLD and without HIV (MASLD controls) on age at biopsy, race/ethnicity, sex, type 2 diabetes, body mass index (BMI) and alanine aminotransferase (ALT) level. Biopsies were scored using NAS., Results: Compared to MASLD-controls, MASLD-PWH had lower steatosis grade (OR: 0.65, 95% CI: (0.47-0.90), p = 0.01), lower lobular inflammation grade (OR: 0.55, 95% CI: (0.34-0.89), p = 0.02), less portal inflammation (OR: 0.42, 95% CI: (0.25-0.72), p = 0.002) and less ballooned hepatocytes (OR: 0.60, 95% CI: (0.41-0.88), p = 0.01). Thus, NAS was lower in MASLD-PWH (OR: 0.69, 95% CI: (0.56-0.85), p < 0.001) than in MASLD controls. There was a trend towards lower prevalence of steatohepatitis in MASLD-PWH (OR: 0.84, 95% CI: (0.68-1.03), p = 0.09). A multivariate analysis demonstrated that MASLD-PWH cases had significantly less steatosis (OR: 0.66, p = 0.03), portal inflammation (OR: 0.34, p = 0.001) and ballooned hepatocytes (OR: 0.55, p = 0.01), yet higher stage fibrosis (OR: 1.42, p = 0.03) compared to MASLD controls., Conclusion: The NAS and histological drivers of fibrosis (e.g. inflammation and hepatocyte ballooning) are less pronounced in MASLD-PWH, and yet fibrosis stage was generally higher when compared to matched controls with MASLD without HIV. This suggests HIV-specific factors beyond hepatic necroinflammation may contribute to fibrosis progression in MASLD-PWH., (© 2024 The Author(s). Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

Background: Protease-activated receptor-1 (PAR1) has emerged as an important link between coagulation and the complications of obesity including metabolic dysfunction-associated steatotic liver disease (MASLD). PAR1 is expressed by various cells and cleaved by different proteases to generate unique tethered agonists that activate distinct signaling pathways. Mice expressing PAR1 with an R41Q mutation have disabled canonical thrombin-mediated signaling, whereas R46Q mice express PAR1 resistant to noncanonical signaling by activated protein C., Methods: Mice with whole body and hepatocyte-selective PAR1 deficiency as well as PAR1 R41Q and R46Q mice were fed a high-fat diet (HFD) to induce MASLD., Results: HFD-fed R41Q mice displayed reduced hepatic steatosis and liver/body weight ratio. In contrast, HFD-fed R46Q mice displayed increased relative liver weight and hepatic steatosis alongside increased serum alanine aminotransferase activity. Surprisingly, despite the distinct impact of PAR1 mutations on steatosis, selective deletion of PAR1 in hepatocytes had no impact. To evaluate a viable PAR1-targeted approach, mice with HFD-induced obesity were treated with the allosteric PAR1 modulator NRD-21, which inhibits canonical PAR1 inflammatory signaling but promotes PAR1 protective, noncanonical anti-inflammatory signaling. NRD-21 treatment reduced plasma tumor necrosis factor-alpha, serum alanine aminotransferase activity, hepatic steatosis, and insulin resistance (Homeostatic Model Assessment for Insulin Resistance) but increased plasma active glucagon-like peptide-1., Conclusion: The results suggest that nonhepatocellular canonical PAR1 cleavage drives MASLD in obese mice and provide translational proof-of-concept that selective pharmacologic modulation of PAR1 yields multiple metabolic benefits in experimental obesity., Competing Interests: Declaration of competing interests C.D. is Chief Strategy Officer and Chief Executive Officer at Function Therapeutics, which provided NRD-21 for these studies. Function Therapeutics did not provide financial support. Beyond research support noted in acknowledgments, no other authors have relevant conflicts of interests to disclose., (Copyright © 2024 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)

Background: We examined the association of objective measures of cardiometabolic risk with progression to a high-risk for advanced fibrosis in patients with metabolic dysfunction-associated steatotic liver disease (MASLD) at initially low- and indeterminate-risk for advanced fibrosis., Methods: We performed a retrospective cohort study of primary care patients with MASLD between 2012 and 2021. We evaluated patients with MASLD and low- or indeterminate-risk Fibrosis-4 Index (FIB-4) scores and followed them until the outcome of a high-risk FIB-4 (≥2.67), or the end of the study period. Exposures of interest were body mass index, systolic blood pressure, hemoglobin A1c, cholesterol, estimated glomerular filtration rate, and smoking status. Variables were categorized by the threshold for primary care therapy intensification. Unadjusted and adjusted Cox regression models were developed for the outcome of time to a high-risk FIB-4 value., Results: The cohort included 1347 patients with a mean follow-up of 3.6 years (SD 2.7). Of the cohort, 258 (19%) had a subsequent FIB-4 > 2.67. In the fully adjusted Cox regression models, mean systolic blood pressure ≥ 150 mm Hg (1.57; 95% confidence interval (CI) 1.02-2.41) and glomerular filtration rate ≤ 59 ml/min (hazard ratio 2.78; 95%CI 2.17-3.58) were associated with an increased hazard of a high-risk FIB-4, while receiving a statin prescription (hazard ratio 0.51; 95%CI 0.39-0.66) was associated with a lower risk., Conclusions: Nearly 1 in 5 primary care patients with MASLD transitioned to a high-risk FIB-4 score during 3.6 years of follow-up, and uncontrolled blood pressure and reduced kidney function were associated with an increased hazard of a FIB-4 at high-risk for advanced fibrosis., Competing Interests: Disclosure The authors have no conflicts of interest to disclose., (Copyright © 2024 AACE. Published by Elsevier Inc. All rights reserved.)

During recent decades, the metabolic dysfunction-associated steatohepatitis (MASH) field has witnessed several paradigm shifts, including the recognition of liver fibrosis as the main predictor of major adverse liver outcomes. Throughout this evolution, liver histology has been recognised as one of the main hurdles in MASH drug development due to its invasive nature, associated cost, and high inter- and intra-reader variability. Collective experience demonstrates the importance of consistency in the central reading process, where consensus methods have emerged as appropriate ways to mitigate against well-known challenges. Using crystalized knowledge in the field, stakeholders should collectively work towards the next paradigm shift, where non-invasive biomarkers will be considered surrogate endpoints for accelerated approval. In this review, we provide an overview of the evolution of the regulatory histology endpoints and the liver biopsy reading process, within the MASH trial landscape, over recent decades; we then review the biggest challenges associated with liver biopsy endpoints. Finally, we discuss and provide recommendations on the best practices for liver biopsy evaluation in MASH drug development., (Copyright © 2024 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Obstructive sleep apnea syndrome (OSAS) is associated with the development and progression of metabolic dysfunction-associated steatotic liver disease (MASLD). Tripartite motif containing 24 (TRIM24) deficiency causes hepatic lipid accumulation and hepatitis. However, the expression, function, and mechanism of TRIM24 in OSAS and MASLD remain unclear. Herein, an OSAS and MASLD mouse model was established by intermittent hypoxia (IH) and high-fat diet. IH- and 1% free fatty acid-induced mouse liver cells served as an in vitro model. TRIM24 and HIF1A were up-regulated under the IH condition. HIF1A enhanced the transcriptional activity of TRIM24. Overexpression of TRIM24 reduced hepatic lipid accumulation, decreased serum levels of total cholesterol, triglyceride, and low-density lipoprotein cholesterol, and increased serum levels of high-density lipoprotein cholesterol in OSAS and MASLD mice. Additionally, overexpression of TRIM24 alleviated inflammation and oxidative stress, and modulated aberrant lipid metabolism. Mechanically, TRIM24 up-regulated the expression of ORM2, a key regulator of hepatic lipogenesis, by binding to H3K27ac and recruiting retinoic acid receptor-α to ORM2 promoter. The cell rescue model was used to verify that ORM2 mediated the hepatoprotective effects of TRIM24. The current study reveals the important role of TRIM24 as an epigenetic coregulator of transcription in OSAS and MASLD, providing additional insights into understanding the pathogenesis and preventing the development of OSAS and MASLD., Competing Interests: Disclosure Statement None declared., (Copyright © 2024 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Background and Methods: Our study sought to evaluate if an association exists between Helicobacter pylori (H. pylori), metabolic dysfunction- associated steatotic liver disease (MASLD), and liver fibrosis in patients with severe obesity (BMI > 35). Our retrospective study included 584 patients over the age of 18 years with severe obesity, who underwent preoperative liver transient elastography (VCTE), upper endoscopy, blood work, and intra-operative liver biopsy concurrent with bariatric surgery at a single institution from July 2020 to September 2021. Liver fibrosis scores including FIB-4, APRI, NAFLD fibrosis score, BARD score, AST: ALT ratio, and NAFLD activity score (NAS) were calculated from the laboratory results and liver biopsy findings. The presence or absence of H. pylori was determined based on gastric biopsies obtained during upper endoscopy. Other variables collected included age, gender, mean preoperative weight, BMI, and the presence or absence of comorbidities. Student's t-test and non-parametric testing were used for the analysis of continuous variables and Chi-square analysis was used for categorical data., Results: Of the 584 patients, 14.7% were H. pylori positive and 85.3% were negative. Liver fibrosis scores including FIB-4, APRI, and NAFLD fibrosis scores were significantly higher in the positive group (p < 0.05), but there was no difference in AST: ALT ratio and BARD score. A significantly higher VCTE steatosis and fibrosis scores were noted in the H. pylori-positive group (p < 0.05). Similarly, a significantly higher NAS (NAFLD activity score) on liver biopsies was noted in the positive group, with all the individual components of NAS (steatosis, lobular inflammation, and hepatocyte ballooning) being significantly higher in the positive group (p < 0.05). A significantly higher incidence of fibrosis on liver biopsies was noted in the positive group overall and across all stages of fibrosis (p < 0.05). There were no significant differences between the groups in relation to gender, mean weight, BMI, presence of comorbidities including Diabetes Mellitus, and laboratory values., Conclusion: Our study demonstrates that H. pylori colonization or infection is associated with a higher risk of development of MASLD and progression to fibrosis. Further, population-based studies are needed to corroborate our findings., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Casein kinase 1 epsilon (CK1ε), a member of the serine/threonine protein kinase family, phosphorylates a broad range of substrates. However, its role in the development of chronic liver diseases remains elusive. This study aimed to investigate the role of CK1ε in the development and progression of metabolic dysfunction-associated steatohepatitis (MASH). Hepatocyte-specific CK1ε knockout (CK1ε ΔHEP ) mice were generated by crossbreeding mice with floxed CK1ε alleles (CK1ε fl/fl ) and Cre-expressing albumin mice. Mice were fed either a Western diet (WD) or a methionine- and choline-deficient diet to induce MASH. CK1ε ΔHEP was associated with a decreased severity of WD- or methionine- and choline-deficient diet-induced MASH, as confirmed by reduced incidence of hepatic lesions and significantly lower levels of alanine aminotransferase, aspartate aminotransferase, and proinflammatory cytokine tumor necrosis factor (TNF)-α. CK1ε ΔHEP WD-fed mice exhibited significant amelioration of total cholesterol, triglycerides, and de novo lipogenic genes, indicating that CK1ε could influence lipid metabolism. CK1ε ΔHEP WD-fed mice showed significantly down-regulated TNF receptor-associated factor (TRAF) 3, phosphorylated (p) transforming growth factor-β-activated kinase 1, p-TRAF-associated NF-κB activator (TANK)-binding kinase 1 (TBK1), and p-AKT levels, thereby affecting downstream mitogen-activated protein kinase signaling, indicating a potential mechanism for the observed rescue. Finally, pharmacologic inhibition of CK1ε with PF670462 improved palmitic acid-induced steatohepatitis in vitro and attenuated WD-induced metabolic profile in vivo. In conclusion, CK1ε up-regulates TNF receptor-associated factor 3, which, in turn, causes transforming growth factor-β-activated kinase 1-dependent signaling, amplifies downstream mitogen-activated protein kinase signaling, modifies p-c-Jun levels, and exacerbates inflammation, all of which are factors in WD-induced metabolic dysfunction-associated steatotic liver disease., Competing Interests: Disclosure Statement None declared., (Copyright © 2024 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Dysregulated metabolism, cell death, and inflammation contribute to the development of metabolic dysfunction-associated steatohepatitis (MASH). Pyroptosis, a recently identified form of programmed cell death, is closely linked to inflammation. However, the precise role of pyroptosis, particularly gasdermin-E (GSDME), in MASH development remains unknown. In this study, we observed GSDME cleavage and GSDME-associated interleukin-1β (IL-1β)/IL-18 induction in liver tissues of MASH patients and MASH mouse models induced by a choline-deficient high-fat diet (CDHFD) or a high-fat/high-cholesterol diet (HFHC). Compared with wild-type mice, global GSDME knockout mice exhibited reduced liver steatosis, steatohepatitis, fibrosis, endoplasmic reticulum stress, lipotoxicity and mitochondrial dysfunction in CDHFD- or HFHC-induced MASH models. Moreover, GSDME knockout resulted in increased energy expenditure, inhibited intestinal nutrient absorption, and reduced body weight. In the mice with GSDME deficiency, reintroduction of GSDME in myeloid cells-rather than hepatocytes-mimicked the MASH pathologies and metabolic dysfunctions, as well as the changes in the formation of neutrophil extracellular traps and hepatic macrophage/monocyte subclusters. These subclusters included shifts in Tim4 + or CD163 + resident Kupffer cells, Ly6C hi pro-inflammatory monocytes, and Ly6C lo CCR2 lo CX3CR1 hi patrolling monocytes. Integrated analyses of RNA sequencing and quantitative proteomics revealed a significant GSDME-dependent reduction in citrullination at the arginine-114 (R114) site of dynamin-related protein 1 (Drp1) during MASH. Mutation of Drp1 at R114 reduced its stability, impaired its ability to redistribute to mitochondria and regulate mitophagy, and ultimately promoted its degradation under MASH stress. GSDME deficiency reversed the de-citrullination of Drp1 R114 , preserved Drp1 stability, and enhanced mitochondrial function. Our study highlights the role of GSDME in promoting MASH through regulating pyroptosis, Drp1 citrullination-dependent mitochondrial function, and energy balance in the intestine and liver, and suggests that GSDME may be a potential therapeutic target for managing MASH., (© 2024. The Author(s), under exclusive licence to ADMC Associazione Differenziamento e Morte Cellulare.)

Intracellular reactive oxygen species (ROS) in steatotic cells pose a problem due to their potential to cause oxidative stress and cellular damage. Delivering engineered phospholipids to intracellular lipid droplets in steatotic hepatic cells, using the cell's inherent intracellular lipid transport mechanisms are investigated. Initially, it is shown that tail-labeled fluorescent lipids assembled into liposomes are able to be transported to intracellular lipid droplets in steatotic HepG2 cells and HHL-5 cells. Further, an antioxidant, an EUK salen-manganese derivative, which has superoxide dismutase-like and catalase-like activity, is covalently conjugated to the tail of a phospholipid and formulated as liposomes for administration. Steatotic HepG2 cells and HHL-5 cells incubated with these antioxidant liposomes have lower intracellular ROS levels compared to untreated controls and non-covalently formulated antioxidants. This first proof-of-concept study illustrates an alternative strategy to equip native organelles in mammalian cells with engineered enzyme activity., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Background and Aims: The global rise of chronic hepatitis B (CHB) superimposed on hepatic steatosis (HS) warrants noninvasive, precise tools for assessing fibrosis progression. This study leveraged machine learning (ML) to develop diagnostic models for advanced fibrosis and cirrhosis in this patient population., Methods: Treatment-naive CHB patients with concurrent HS who underwent liver biopsy in 10 medical centers were enrolled as a training cohort and an independent external validation cohort (NCT05766449). Six ML models were implemented to predict advanced fibrosis and cirrhosis. The final models, derived from SHAP (Shapley Additive exPlanations), were compared with Fibrosis-4 Index, nonalcoholic fatty liver disease Fibrosis Score, and aspartate aminotransferase-to-platelet ratio index using the area under receiver-operating characteristic curve (AUROC) and decision curve analysis (DCA)., Results: Of 1,198 eligible patients, the random forest model achieved AUROCs of 0.778 (95% confidence interval [CI], 0.749-0.807) for diagnosing advanced fibrosis (random forest advanced fibrosis model) and 0.777 (95% CI, 0.748-0.806) for diagnosing cirrhosis (random forest cirrhosis model) in the training cohort, and maintained high AUROCs in the validation cohort. In the training cohort, the random forest advanced fibrosis model obtained an AUROC of 0.825 (95% CI, 0.787-0.862) in patients with hepatitis B virus DNA ≥10 5 IU/mL, and the random forest cirrhosis model had an AUROC of 0.828 (95% CI, 0.774-0.883) in female patients. The 2 models outperformed Fibrosis-4 Index, nonalcoholic fatty liver disease Fibrosis Score, and aspartate aminotransferase-to-platelet ratio index in the training cohort, and also performed well in the validation cohort., Conclusions: The random forest models provide reliable, noninvasive tools for identifying advanced fibrosis and cirrhosis in CHB patients with concurrent HS, offering a significant advancement in the comanagement of the 2 diseases., Clinicaltrials: gov, Number: NCT05766449., (Copyright © 2024 AGA Institute. Published by Elsevier Inc. All rights reserved.)

The rising prevalence of obesity-related illnesses, such as metabolic steatotic liver disease (MASLD), represents a significant global public health concern. This disease affects approximately 30 % of the adult population and is the result of metabolic abnormalities rather than alcohol consumption. Additionally, MASLD is associated with an increased risk of cardiovascular disease (CVD), chronic liver disease, and a variety of cancers, particularly gastrointestinal cancers. Clonal hematopoiesis (CH) is a biological state characterized by the expansion of a population of blood cells derived from a single mutated hematopoietic stem cell. The presence of CH in the absence of a diagnosed blood disorder or cytopenia is known as clonal hematopoiesis of indeterminate potential (CHIP), which itself increases the risk of hematological malignancies and CVD. Steatotic liver disease may also complicate the clinical course of cancer patients receiving antineoplastic agents, a condition referred to as chemotherapy induced steatohepatitis (CASH). This review will present an outline of the various aspects of MASLD, including complications. Furthermore, it will summarize the existing knowledge on the emerging association between CHIP and MASLD and present the available data on patient cases with concurrent MASLD and hematological neoplasms. Finally, it will provide a brief overview of the chemotherapeutic drugs associated with CASH, the underlying pathophysiologic mechanisms and their clinical implications., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024. Published by Elsevier Inc.)

Background and Aims: The hallmark of NAFLD or hepatic steatosis is characterized by lipid droplet (LD) accumulation in hepatocytes. Autophagy may have profound effects on lipid metabolism and innate immune response. However, how innate immune activation may regulate the autophagic degradation of intracellular LDs remains elusive., Approach and Results: A mouse model of a high-fat diet-induced NASH was used in the myeloid-specific stimulator of interferon genes (STING) knockout or STING/yes-associated protein (YAP) double knockout mice. Liver injury, lipid accumulation, lipid droplet proteins, autophagic genes, chromatin immunoprecipitation coupled with massively parallel sequencing, and RNA-Seq were assessed in vivo and in vitro . We found that high-fat diet-induced oxidative stress activates STING and YAP pathways in hepatic macrophages. The acrophage STING deficiency (myeloid-specific STING knockout) enhances nuclear YAP activity, reduces lipid accumulation, and increases autophagy-related proteins ATG5, ATG7, and light chain 3B but diminishes LD protein perilipin 2 expression. However, disruption of STING and YAP (myeloid STING and YAP double knockout) increases serum alanine aminotransferase and triglyceride levels and reduces β-fatty acid oxidation gene expression but augments perilipin 2 levels, exacerbating high-fat diet-induced lipid deposition. Chromatin immunoprecipitation coupled with massively parallel sequencing reveals that macrophage YAP targets transmembrane protein 205 and activates AMP-activated protein kinase α, which interacts with hepatocyte mitofusin 2 and induces protein disulfide isomerase activation. Protein disulfide isomerase activates hypoxia-inducible factor-1α signaling, increases autophagosome colocalization with LDs, and promotes the degradation of perilipin 2 by interacting with chaperone-mediated autophagy chaperone HSC70., Conclusions: The macrophage STING-YAP axis controls hepatic steatosis by reprogramming lipid metabolism in a transmembrane protein 205/mitofusin 2/protein disulfide isomerase-dependent pathway. These findings highlight the regulatory mechanism of the macrophage STING-driven YAP activity on lipid control., (Copyright © 2023 American Association for the Study of Liver Diseases.)

Fibroblast growth factor 21 (FGF21) is a promising target for treatment of obesity-associated diseases including metabolic dysfunction-associated steatohepatitis (MASH) and atherosclerosis. We evaluated the effects of the bispecific anti-FGF21-β klotho (KLB) agonist antibody bFKB1 in a preclinical model of MASH and atherosclerosis. Low-density lipoprotein receptor knockout (Ldlr-/-).Leiden mice received a high-fat diet for 20 weeks, followed by treatment with an isotype control antibody or bFKB1 for 12 weeks. Effects on plasma risk markers and (histo)pathology of liver, adipose tissue, and heart were evaluated alongside hepatic transcriptomics analysis. bFKB1 lowered body weight (-21%) and adipose tissue mass (-22%) without reducing food intake. The treatment also improved plasma insulin (-80%), cholesterol (-48%), triglycerides (-76%), alanine transaminase (ALT: -79%), and liver weight (-43%). Hepatic steatosis and inflammation were strongly reduced (macrovesicular steatosis -34%; microvesicular steatosis -100%; inflammation -74%) and while the total amount of fibrosis was not affected, bFKB1 did decrease new collagen formation (-49%). Correspondingly, hepatic transcriptomics and pathway analysis revealed the mechanistic background underlying these histological improvements, demonstrating broad inactivation of inflammatory and profibrotic transcriptional programs by bFKB1. In epididymal white adipose tissue, bFKB1 reduced adipocyte size (-16%) and inflammation (-52%) and induced browning, signified by increased uncoupling protein-1 (UCP1) protein expression (8.5-fold increase). In the vasculature, bFKB1 had anti-atherogenic effects, lowering total atherosclerotic lesion area (-38%). bFKB1 has strong beneficial metabolic effects associated with a reduction in hepatic steatosis, inflammation, and atherosclerosis. Analysis of new collagen formation and profibrotic transcriptional programs indicate that bFKB1 treatment may have antifibrotic potential in a longer treatment duration as well., (© 2024 The Author(s). The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Hepatic steatosis, a common liver disorder, can progress to severe conditions such as nonalcoholic steatohepatitis and cirrhosis. While olfactory receptors are primarily known for detecting odorants, emerging evidence suggests that they also influence liver lipid metabolism. This study generated a mouse model with a specific knockout of olfactory receptor 23 (MOR23) to investigate its role in hepatic steatosis. MOR23 knockout mice on a normal diet showed a slight increase in liver weight compared to wild-type (WT) mice. When fed a high-fat diet (HFD), these knockout mice exhibited accelerated hepatic steatosis, indicated by increased liver weight and hepatic triglyceride levels. Our findings suggest that the cyclic adenosine monophosphate/protein kinase A/AMP-activated protein kinase pathway is involved in the role of MOR23, leading to the upregulation of peroxisome proliferator-activated receptor α, peroxisome proliferator-activated receptor-γ coactivator 1-α, and their target β-oxidation genes in the liver. MOR23 also appeared to regulate lipogenesis and free fatty acid uptake in HFD-fed mice, potentially by influencing sterol regulatory element-binding protein 1 activity. Notably, administering a potential MOR23 ligand, cedrene, attenuated hepatic steatosis in WT mice, but these effects were largely nullified in MOR23 knockout mice. These findings provide valuable insights into the in vivo role of MOR23 in hepatic steatosis development., (© 2024 The Author(s). The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

We aim to evaluate the prevalence of steatotic liver disease (SLD) in United States (US) adolescents and explore whether metabolic dysfunction-associated steatotic liver disease (MASLD) can identify individuals with clinically significant fibrosis (CSF) in this study. The prevalence of SLD and its categories, including MASLD, metabolic dysfunction and alcohol associated liver disease (MetALD), alcohol related liver disease (ALD) and other SLD were determined. Weighted multivariable logistic regression analysis was conducted to evaluate the association between MASLD and CSF in adolescents with SLD. Among the total 1,446 US adolescents, SLD was present in 291 (20.1%) of individuals, including 260 (17.9%) for MASLD, 9 (0.6%) for MetALD and 5 (0.3%) for ALD. Only 58 (4%) had CSF. Patients with SLD showed a higher prevalence of CSF (9.6% vs. 2.6%, p < 0.001). Among patients with SLD, 89.3% met the MASLD criteria. The risk of CSF in patients with MASLD was not significantly different (odds ratio [OR] = 1.07, 95% confidence interval [CI] = 0.30-3.83, p = 0.9180) compared with those without MASLD. MASLD was met by most of the US adolescents with SLD. Moreover, MASLD was not associated with higher prevalence of CSF among adolescents with SLD., (© 2024. The Author(s).)

Ghrelin is an orexigenic peptide released by gastric ghrelin cells that contributes to obesity and hepatic steatosis. The mechanosensitive ion channel Piezo1 in gastric ghrelin cells inhibits the synthesis and secretion of ghrelin in response to gastric mechanical stretch. We sought to modulate hepatic lipid metabolism by manipulating Piezo1 in gastric ghrelin cells. Mice with a ghrelin cell-specific deficiency of Piezo1 ( Ghrl-Piezo1 -/- ) had hyperghrelinemia and hepatic steatosis when fed a low-fat or high-fat diet. In these mice, hepatic lipid accumulation was associated with changes in gene expression and in protein abundance and activity expected to increase hepatic fatty acid synthesis and decrease lipid β-oxidation. Pharmacological inhibition of the ghrelin receptor improved hepatic steatosis in Ghrl-Piezo1 -/- mice, thus confirming that the phenotype of these mice was due to overproduction of ghrelin caused by inactivation of Piezo1. Gastric implantation of silicone beads to induce mechanical stretch of the stomach inhibited ghrelin synthesis and secretion, thereby helping to suppress fatty liver development induced by a high-fat diet in wild-type mice but not in Ghrl-Piezo1 -/- mice. Our study elucidates the mechanism by which Piezo1 in gastric ghrelin cells regulate hepatic lipid accumulation, providing insights into potential treatments for fatty liver.

Myotonic Dystrophy type 1 (DM1), a highly prevalent form of muscular dystrophy, is caused by (CTG) n repeat expansion in the DMPK gene. Much of DM1 research has focused on the effects within the muscle and neurological tissues; however, DM1 patients also suffer from various metabolic and liver dysfunctions such as increased susceptibility to metabolic dysfunction-associated fatty liver disease (MAFLD) and heightened sensitivity to certain drugs. Here, we generated a liver-specific DM1 mouse model that reproduces molecular and pathological features of the disease, including susceptibility to MAFLD and reduced capacity to metabolize specific analgesics and muscle relaxants. Expression of CUG-expanded (CUG) exp repeat RNA within hepatocytes sequestered muscleblind-like proteins and triggered widespread gene expression and RNA processing defects. Mechanistically, we demonstrate that increased expression and alternative splicing of acetyl-CoA carboxylase 1 drives excessive lipid accumulation in DM1 livers, which is exacerbated by high-fat, high-sugar diets. Together, these findings reveal that (CUG) exp RNA toxicity disrupts normal hepatic functions, predisposing DM1 livers to injury, MAFLD, and drug clearance pathologies that may jeopardize the health of affected individuals and complicate their treatment., (© 2024. The Author(s).)

Metabolic dysfunction-associated Steatohepatitis (MASH), is a prominent cause for liver cirrhosis. MASH-cirrhosis is responsible for liver complications and there is no specific treatment. To develop new therapeutic approaches, animal models are needed. The aim of this study was to develop a fast animal model of MASH-cirrhosis in rats reflecting the human disease. Carbon tetrachloride (CCl 4 ) injections in combination with a high-fat Western diet (WD) were used to induce MASH-cirrhosis. To accelerate liver injury, animals received phenobarbital (PB) in their drinking water using two different regimens. Rats developed advanced MASH-cirrhosis characterized by portal hypertension, blood biochemistry, hepatic ballooning, steatosis, inflammation and fibrosis. Importantly, rats receiving low-dose PB for the long term (LT) showed ascites after 6 weeks, whereas rats with high-dose short-term (ST) PB developed ascites after 8 weeks. ST- and LT-treated rats showed increased portal pressure (PP) and decreased mean arterial pressure (MAP). Of note, hepatocyte ballooning was only observed in the LT group. The LT administration of low-dose PB with CCl 4 intoxication and WD represents a fast and reproducible rat model mimicking decompensated MASH-cirrhosis in humans. Thus, CCl 4 + WD with LT low-dose phenobarbital treatment might be the preferred rat animal model for drug development in MASH-cirrhosis.

It is known that both transcriptional and post-transcriptional mechanisms control messenger RNA (mRNA) levels. Compared to transcriptional regulations, our understanding of how post-transcriptional regulations adapt during fatty liver progression at the whole-transcriptome level is unclear. While traditional RNA-seq analysis uses only reads mapped to exons to determine gene expression, recent studies support the idea that intron-mapped reads can be reliably used to estimate gene transcription. In this study, we analyzed differential gene expression at both the exon and intron levels using two liver RNA-seq datasets from mice that were fed a high-fat diet for seven weeks (mild fatty liver) or thirty weeks (severe fatty liver). We found that the correlation between gene transcription and mature mRNA levels was much lower in mice with mild fatty liver as compared with mice with severe fatty liver. This result indicates broad post-transcriptional regulations for early fatty liver and such regulations are compromised for severe fatty liver. Specifically, gene ontology analysis revealed that genes involved in synapse organization and cell adhesion were transcriptionally upregulated, while their mature mRNAs were unaffected in mild fatty liver. Further characterization of post-transcriptionally suppressed genes in early fatty liver revealed that their mRNAs harbor a significantly longer 3' UTR, one of the major features that may subject RNA transcripts to nonsense-mediated RNA decay (NMD). We further show that the expression of representative genes that were post-transcriptionally suppressed were upregulated in mice with a hepatocyte-specific defect of NMD. Finally, we provide data supporting a time-dependent decrease in NMD activity in the liver of a diet-induced metabolic-dysfunction-associated fatty liver disease mouse model. In summary, our study supports the conclusion that NMD is essential in preventing unwanted/harmful gene expression at the early stage of fatty liver and such a mechanism is lost due to decreased NMD activity in mice with severe fatty liver.

Background: Selecting the optimal non-invasive diagnostic model for MASLD (Metabolic Dysfunction-Associated Steatosis Liver Disease) and steatosis progression is a critical issue given the variety of available models. We aimed to compare the performance of eight clinical prediction models for diagnosing and predicting the progression of hepatic steatosis using MRI-PDFF (Magnetic Resonance Imaging-Derived Proton Density Fat Fraction), and validate the findings with FibroScan and histopathological results., Methods: In this study, 846 participants were initially enrolled, with 108 undergoing liver biopsy and 706 completing one-year follow-up, including 26 who underwent repeat biopsy. We calculated scores for eight clinical prediction models (FAST, KNAFLD, HSI, FLI, Liver Fat Score, Liver Fat Equation, BAAT, LAP) using collected clinical data and defined steatosis progression as a 30% relative increase in liver fat content (LFC) measured by MRI-PDFF. CAP(Controlled Attenuation Parameter) and LSM (Liver Stiffness Measurement) were obtained by Fibroscan. MRI-PDFF served as the reference standard for evaluating model accuracy, and sensitivity analyses were performed using liver biopsy and Fibroscan results., Results: Among the eight clinical models, NAS (nonalcoholic fatty liver disease activity score) showed higher correlation with the FAST and KNAFLD models (r: 0.62 and 0.52, respectively). Among the whole cohort (N = 846), KNAFLD was the best model for predicting different degrees of hepatic steatosis (AUC = 0.84). When the KNAFLD score was above 2.935, LFC was significantly higher (4.4% vs. 19.7%, P < 0.001). After 1 year of follow-up (N = 706), FAST performed best in predicting MASLD progression (AUC = 0.84); with dFAST > -0.02, LFC increased (8.6-10.9%, P < 0.05), mean LSM increased by 0.51 kPa, and with dFAST < -0.02, LFC significantly decreased (11.5-8.5%, P < 0.05), mean LSM and NAS decreased by 0.87 kPa and 0.76, respectively (both P < 0.05)., Conclusions: Most models demonstrated good diagnostic and prognostic capabilities for hepatic steatosis, with FAST and KNAFLD showing particular promise as primary non-invasive tools in clinical practice., Trail Registration: Chinese Clinical Trial Registry NO: ChiCTR2100054743, Registered December 26, 2021., (© 2024. The Author(s).)

GDF15 and FGF21, stress-responsive cytokines primarily secreted from the liver, are promising therapeutic targets for metabolic dysfunction-associated steatotic liver disease (MASLD). However, the interaction between GDF15 and FGF21 remains unclear. We examined the effects of hepatocyte-specific GDF15 or FGF21 overexpression in high-fat diet (HFD)-fed mice for 8 weeks. Hydrodynamic injection of GDF15 or FGF21 sustained high circulating levels of GDF15 or FGF21, respectively, resulting in marked reductions in body weight, epididymal fat mass, insulin resistance, and hepatic steatosis. In addition, GDF15 treatment led to early reduction in body weight despite no change in food intake, indicating the role of GDF15 other than appetite loss. GDF15 treatment increased liver-derived serum FGF21 levels, whereas FGF21 treatment did not affect GDF15 expression. GDF15 promoted eIF2α phosphorylation and XBP1 splicing, leading to FGF21 induction. In murine AML12 hepatocytes treated with free fatty acids (FFAs), GDF15 overexpression upregulated Fgf21 mRNA levels and promoted eIF2α phosphorylation and XBP1 splicing. Overall, continuous exposure to excess FFAs resulted in a gradual increase of β-oxidation-derived reactive oxygen species and endoplasmic reticulum stress, suggesting that GDF15 enhanced this pathway and induced FGF21 expression. GDF15- and FGF21-related crosstalk is an important pathway for the treatment of MASLD., (© 2024. The Author(s).)

Background: Metabolic dysfunction-associated steatohepatitis (MASH) is a growing global health concern with no effective pharmacological treatments. SNP-630, a newly developed synthetic molecule with multiple mechanisms of action, and a mixture of two of its active metabolites (SNP-630-MS) inhibit CYP2E1 expression to prevent reactive oxygen species generation, thereby reducing the accumulation of hepatic triglycerides and lowering chemokine levels. This study investigated the SNP-630's potential to alleviate the liver injury in MASH and its efficacy in both a mouse model and patients with MASH to identify a drug candidate that targets multiple pathways implicated in MASH., Methods: SNP-630 and SNP-630-MS were separately administered to the MASH mouse model. The tolerability, safety, and efficacy of SNP-630-MS were also evaluated in 35 patients with MASH. The primary endpoint of the study was assessment of the changes in serum alanine aminotransferase (ALT) levels from baseline to week 12, while the secondary endpoints included the evaluation of liver inflammation, steatosis, and fibrosis parameters and markers., Results: SNP-630 treatment in mice improved inflammation, liver steatosis, and fibrosis compared with that in the MASH control group. Both SNP-630 and SNP-630-MS treatments markedly reduced ALT levels, hepatic triglyceride content, and the expression of inflammatory cytokines monocyte chemoattractant protein 1 and fibrotic collagen (i.e., Col1a1, Col3a1, and Timp1) in mice. In the clinical trial, patients treated with SNP-630-MS exhibited significant improvement in ALT levels at week 12 compared with baseline levels, with no reports of severe adverse events. This improvement in ALT levels surpassed that achieved with most other MASH candidates. SNP-630-MS demonstrated potential antifibrotic effects, as evidenced by a significant decrease in the levels of fibrogenesis-related biomarkers such as CCL4, CCL5, and caspase 3. Subgroup analysis using FibroScan measurements further indicated the efficacy of SNP-630-MS in ameliorating liver fibrosis., Conclusions: SNP-630 and SNP-630-MS demonstrated favorable results in mice. SNP-630-MS showed excellent tolerability in mice and patients with MASH. Efficacy analyses indicated that SNP-630-MS improved liver steatosis and injury in patients with MASH, suggesting that SNP-630 and 630-MS are promising therapeutic options for MASH. Larger scale clinical trials remain warranted to assess the efficacy and safety of SNP-630 in MASH., Trial Registration: ClinicalTrials.gov NCT03868566. Registered 06 March 2019-Retrospectively registered, https://clinicaltrials.gov/study/NCT03868566., (© 2024. The Author(s).)

Preclinical and clinical studies suggest that lipid-induced hepatic insulin resistance is a primary defect that predisposes to dysfunction in islets, implicating a perturbed liver-pancreas axis underlying the comorbidity of T2DM and MASLD. To investigate this hypothesis, we developed a human biomimetic microphysiological system (MPS) coupling our vascularized liver acinus MPS (vLAMPS) with pancreatic islet MPS (PANIS) enabling MASLD progression and islet dysfunction to be assessed. The modular design of this system (vLAMPS-PANIS) allows intra-organ and inter-organ dysregulation to be deconvoluted. When compared to normal fasting (NF) conditions, under early metabolic syndrome (EMS) conditions, the standalone vLAMPS exhibited characteristics of early stage MASLD, while no significant differences were observed in the standalone PANIS. In contrast, with EMS, the coupled vLAMPS-PANIS exhibited a perturbed islet-specific secretome and a significantly dysregulated glucose stimulated insulin secretion response implicating direct signaling from the dysregulated liver acinus to the islets. Correlations between several pairs of a vLAMPS-derived and a PANIS-derived factors were significantly altered under EMS, as compared to NF conditions, mechanistically connecting MASLD and T2DM associated hepatic-factors with islet-derived GLP-1 synthesis and regulation. Since vLAMPS-PANIS is compatible with patient-specific iPSCs, this platform represents an important step towards addressing patient heterogeneity, identifying disease mechanisms, and advancing precision medicine., (© 2024. The Author(s).)

The platelet-derived growth factor (PDGF) family contributes to the progression of steatohepatitis; however, changes in and the characteristics of isoform-specific expression remain unclear. Since diabetes is a major driver of metabolic dysfunction-associated steatohepatitis (MASH), we characterized the mouse model of diabetic MASH (dMASH) by focusing on PDGF signaling. Pdgfa-d expression was markedly higher in hepatic stellate cells among flow-sorted cells in control mice and also increased in dMASH. In contrast, a reanalysis of human single-cell RNA-Seq data showed the distinct distribution of each PDGF isoform with disease progression. Furthermore, inflammation and fibrosis in the liver were less severe in diabetic MASH using tamoxifen-induced PDGF receptor β (PDGFRβ)-deficient mice (KO) than in control dMASH using floxed mice (FL) at 12 weeks old. Despite the absence of tumors, the expression of tumor-related genes was lower in KO than in FL. Tumorigenesis was significantly lower in 20-week-old KO. An Ingenuity Pathway Analysis of differentially expressed miRNA between FL and KO identified functional networks associated with hepatotoxicity and cancer. Therefore, PDGFRβ signals play important roles in the progression of steatohepatitis and tumorigenesis in MASH, with the modulation of miRNA expression posited as a potential underlying mechanism., (© 2024. The Author(s).)

The crosstalk between adipose tissue and the liver is finely controlled to maintain metabolic health. Yet, how adipose tissue controls toxic free fatty acid overflow into the liver remains incompletely understood. Here, we show that adipocyte activating transcription factor 3 (ATF3) was induced in human or mouse obesity. Adipocyte Atf3 -/- (Atf3 Adi-/- ) mice developed obesity, glucose intolerance, and metabolic dysfunction-associated steatohepatitis (MASH) in chow diet, high-fat diet, or Western diet-fed mice. Blocking fatty acid flux by inhibiting hepatocyte CD36, but not the restoration of hepatic AMPK signaling, prevented the aggravation of MASH in Atf3 Adi-/- mice. Further studies show that the loss of adipocyte ATF3 increased lipolysis via inducing adipose triglyceride lipase, which in turn induced lipogenesis and inflammation in hepatocytes. Moreover, Atf3 Adi-/- mice had reduced energy expenditure and increased adipose lipogenesis and inflammation. Our data demonstrate that adipocyte ATF3 is a gatekeeper in counteracting MASH development under physiological and pathological conditions., (© 2024. The Author(s).)

This study aimed to address the diagnostic challenges in distinguishing between alcohol-related liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD). We utilized whole-slide imaging technology to conduct a comprehensive digital analysis of liver specimens collected from patients undergoing transplantation. This study included 36 and 17 patients with ALD and MASLD cirrhosis, respectively, who underwent transplantation at our institution. Digital slides were analyzed for fibrosis patterns using FibroNest™. Patient background characteristics were comparable between ALD (n = 36) and MASLD (n = 17) groups, except for sex. The ALD group exhibited thicker collagen per strand, longer and more flexural fibrosis, and a more heterogeneous distribution than the MASLD group. In patients with ALD and concomitant metabolic dysfunction, fiber distribution became relatively uniform, resembling MASLD. Application of the phenotypic fibrosis composite score achieved 100% sensitivity and specificity for ALD/MASLD diagnosis. Digital pathological analysis of the fibrosis patterns showed morphological differences between ALD and MASLD. This approach holds promise for histological differentiation, providing valuable insights beyond the current definitions based solely on alcohol intake. This study emphasizes the potential of digital pathology in refining the diagnostic criteria for hepatic disorders., (© 2024. The Author(s).)

Background: Statins have multiple benefits in patients with metabolic-associated steatotic liver disease (MASLD)., Aim: To explore the effects of statins on the long-term risk of all-cause mortality, liver-related clinical events (LREs) and liver stiffness progression in patients with MASLD., Methods: This cohort study collected data on patients with MASLD undergoing at least two vibration-controlled transient elastography examinations at 16 tertiary referral centres. Cox regression analysis was performed to examine the association between statin usage and long-term risk of all-cause mortality and LREs stratified by compensated advanced chronic liver disease (cACLD): baseline liver stiffness measurement (LSM) of ≥10 kPa. Liver stiffness progression was defined as an LSM increase of ≥20% for cACLD and from <10 kPa to ≥10 or LSM for non-cACLD. Liver stiffness regression was defined as LSM reduction from ≥10 kPa to <10 or LSM decrease of ≥20% for cACLD., Results: We followed up 7988 patients with baseline LSM 5.9 kPa (IQR 4.6-8.2) for a median of 4.6 years. At baseline, 40.5% of patients used statins, and cACLD was present in 17%. Statin usage was significantly associated with a lower risk of all-cause mortality (adjusted HR=0.233; 95% CI 0.127 to 0.426) and LREs (adjusted HR=0.380; 95% CI 0.268 to 0.539). Statin usage was also associated with lower liver stiffness progression rates in cACLD (HR=0.542; 95% CI 0.389 to 0.755) and non-cACLD (adjusted HR=0.450; 95% CI 0.342 to 0.592), but not with liver stiffness regression (adjusted HR=0.914; 95% CI 0.778 to 1.074)., Conclusions: Statin usage was associated with a relatively lower long-term risk of all-cause mortality, LREs and liver stiffness progression in patients with MASLD., Competing Interests: Competing interests: TC-FY reported serving as an advisory committee member and a speaker for Gilead Sciences outside the submitted work. EAT reported receiving personal fees as advisory board member for Boehringer, Novo Nordisk, Pfizer and Siemens; receiving speaker fees from Echosens, Novo Nordisk and AbbVie outside the submitted work. HH reported personal fees from AstraZeneca, personal fees from Bristol Myers-Squibb, personal fees from MSD, personal fees from Novo Nordisk, personal fees from Boehringer Ingelheim, personal fees from KOWA and personal fees from GW Phara outside the submitted work, and grants from AstraZeneca, grants from Echosens, grants from Gilead Sciences, grants from Intercept, grants from MSD, grants from Novo Nordisk and grants from Pfizer outside the submitted work. JB reported receiving grants and personal fees from Echosens outside the submitted work. JLC reported receiving other from Echosens Clinical Trials during the conduct of the study; grants from Roche Pharma and other from Gilead Advisory Board outside the submitted work. WKC reported serving as consultant or advisory board member for Zuellig Pharma, Abbott, Roche, AbbVie, Boehringer Ingelheim and Novo Nordisk; and a speaker for Novo Nordisk, Abbott, Echosens, Viatris and Hisky Medical. AJS reported receiving grants from Intercept, personal consulting fees from Gilead, grants from Merck, personal consulting fees from Pfizer, grants and personal consulting fees from Eli Lilly, grants and personal consulting fees from Novo Nordisk, Boehringer Ingelheim, Novartis, Histoindex, and stock options from Genfit, Tiziana, Durect, Inversago and personal consulting fees from Genentech, ALnylam, Regeneron, Zydus, LG chem, Hanmi, Madrigal, Path AI, 89 Bio and stock options from Galmed outside the submitted work. VdL reported receiving non-financial support from Echosens during the conduct of the study. PNN reported receiving grants from Novo Nordisk, advisory board and personal consulting fees, honoraria for lectures and travel expenses from Novo Nordisk, personal consulting and advisory board fees from Boehringer Ingelheim, Gilead, Intercept, Poxel Pharmaceuticals, Bristol-Myers Squibb, Pfizer, MSD, Sun Pharma, Eli Lilly, Madrigal, GSK and non-financial support for educational events from AiCME outside the submitted work. LC reported receiving personal fees for consulting and speakers bureau from Echosens during the conduct of the study; personal consultancy fees from Boston pharmaceutical and Gilead, speaker bureau and consultancy personal fees from GSK, personal speaker bureau fees from Inventiva, personal consultancy fees from Madrigal, personal Consultancy fees from MSD and Novo Nordisk, personal consultancy fees from Pfizer, Sagimet and Siemens Healthineers outside the submitted work. CF reported being in the full-time employment of Echosens during the conduct of the study. GL-HW reported receiving personal fees from Echosens during the conduct of the study; grants from Gilead Sciences Research outside the submitted work. MS-WC reported being in the full-time employment of Echosens during the conduct of the study. MR-G reported receiving personal fees from Echosens outside the submitted work. SUK reported personal fees from Gilead Sciences, personal fees from GSK, personal fees from Bayer, personal fees from Eisai, personal fees from AbbVie, personal fees from Echosens, personal fees from MSD, personal fees from Bristol-Myers Squibb and personal fees from AstraZeneca outside the submitted work, and grants from AbbVie, grants from Bristol-Myers Squibb, and grants from Gilead Sciences outside the submitted work. VW-SW reported receiving personal speaker fees from Abbott, consultant and speaker fees from AbbVie, personal consultant fees from Boehringer Ingelheim, Echosens, Gilead Sciences, grants from Gilead Sciences, personal consultant fees from Intercept, Inventiva, Novo Nordisk, personal consultant fees from Pfizer, Sagimet Biosciences, TARGET PharmaSolutions, personal speaker fees from Unilab, personal consultant fees from Visirna, and being a cofounder of Illuminatio outside the submitted work. CDB has received grant support from Echosens. No other disclosures were reported., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

The inhibitor-kappaB kinase epsilon (IKKε) represents a non-canonical IκB kinase that modulates NF-κB activity and interferon I responses. Inhibition of this pathway has been linked with atherosclerosis and metabolic dysfunction-associated steatotic liver disease (MASLD), yet the results are contradictory. In this study, we employed a combined model of hepatic PCSK9 D377Y overexpression and a high-fat diet for 16 weeks to induce atherosclerosis and liver steatosis. The development of atherosclerotic plaques, serum lipid concentrations, and lipid metabolism in the liver and adipose tissue were compared between wild-type and IKKε knock-out mice. The formation and progression of plaques were markedly reduced in IKKε knockout mice, accompanied by reduced serum cholesterol levels, fat deposition, and macrophage infiltration within the plaque. Additionally, the development of a fatty liver was diminished in these mice, which may be attributed to decreased levels of multiple lipid species, particularly monounsaturated fatty acids, triglycerides, and ceramides in the serum. The modulation of several proteins within the liver and adipose tissue suggests that de novo lipogenesis and the inflammatory response are suppressed as a consequence of IKKε inhibition. In conclusion, our data suggest that the knockout of IKKε is involved in mechanisms of both atherosclerosis and MASLD. Inhibition of this pathway may therefore represent a novel approach to the treatment of cardiovascular and metabolic diseases.

Metabolic dysfunction-associated steatohepatitis (MASH) is a common but frequently unrecognized complication of obesity and type 2 diabetes. The association between these conditions is multifaceted and involves complex interactions between metabolic, inflammatory, and genetic factors. Here we assess the underlying structural and molecular processes focusing on the immunological phase of MASH in the nonobese inflammation and fibrosis (NIF) mouse model and compare it to the human disease as well as other murine models. Histopathology together with synchrotron-radiation-based x-ray micro-computed tomography (SRµCT) was used to investigate structural changes within the hepatic sinusoids network in the NIF mouse in comparison to patients with different severities of MASH. A time-course, bulk RNA-sequencing analysis of liver tissue from NIF mice was performed to identify the dynamics of key processes associated with the pathogenesis. Transcriptomics profiling of the NIF mouse revealed a gradual transition from an initially reactive inflammatory response to a regenerative, pro-fibrotic inflammatory response suggesting new avenues for treatment strategies that focus on immunological targets. Despite the lack of metabolic stress induced liver phenotype, a large similarity between the NIF mouse and the immunological phase of human MASH was detected. The translational value was further supported by the comparative analyses with MASH patients and additional animal models. Finally, the impact of diets known to induce metabolic stress, was explored in the NIF mouse. An obesogenic diet was found to induce key physiological, metabolic, and histologic changes akin to those observed in human MASH., (© 2024. The Author(s).)

Fibroblast growth factor 21 (FGF21) is essential for modulating hepatic homeostasis, but the impact of FGF21 on liver graft injury remains uncertain. Here, we show that high FGF21 levels in liver graft and serum are associated with improved graft function and survival in liver transplantation (LT) recipients. FGF21 deficiency aggravates early graft injury and activates arachidonic acid metabolism and regional inflammation in male mouse models of hepatic ischemia/reperfusion (I/R) injury and orthotopic LT. Mechanistically, FGF21 deficiency results in abnormal activation of the arachidonate 15-lipoxygenase (ALOX15)/15-hydroxy eicosatetraenoic acid (15-HETE) pathway, which triggers a cascade of innate immunity-dominated pro-inflammatory responses in grafts. Notably, the modulating role of FGF21/ALOX15/15-HETE pathway is more significant in steatotic livers. In contrast, pharmacological administration of recombinant FGF21 effectively protects against hepatic I/R injury. Overall, our study reveals the regulatory mechanism of FGF21 and offers insights into its potential clinical application in early liver graft injury after LT., (© 2024. The Author(s).)

Objectives: Severe macrovesicular steatosis in donor livers is associated with primary graft dysfunction. The Banff Working Group on Liver Allograft Pathology has proposed recommendations for steatosis assessment of donor liver biopsy specimens with a consensus for defining "large droplet fat" (LDF) and a 3-step algorithmic approach., Methods: We retrieved slides and initial pathology reports from potential liver donor biopsy specimens from 2010 to 2021. Following the Banff approach, we reevaluated LDF steatosis and employed a computer-assisted manual quantification protocol and artificial intelligence (AI) model for analysis., Results: In a total of 113 slides from 88 donors, no to mild (<33%) macrovesicular steatosis was reported in 88.5% (100/113) of slides; 8.8% (10/113) was reported as at least moderate steatosis (≥33%) initially. Subsequent pathology evaluation, following the Banff recommendation, revealed that all slides had LDF below 33%, a finding confirmed through computer-assisted manual quantification and an AI model. Correlation coefficients between pathologist and computer-assisted manual quantification, between computer-assisted manual quantification and the AI model, and between the AI model and pathologist were 0.94, 0.88, and 0.81, respectively (P < .0001 for all)., Conclusions: The 3-step approach proposed by the Banff Working Group on Liver Allograft Pathology may be followed when evaluating steatosis in donor livers. The AI model can provide a rapid and objective assessment of liver steatosis., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

We aimed to compare the associations of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) with coronary artery calcification (CAC). Patients who simultaneously underwent ultrasonography to diagnose hepatic steatosis and cardiac computed tomography to detect CAC were included. The presence and severity of CAC were defined with CAC-score thresholds of > 0 and > 300, respectively, and patients were divided into the following groups: no MASLD or MAFLD (reference), MASLD-only, MAFLD-only, and overlapping groups. Overall, 1,060/2,773 (38.2%) patients had CAC, of which 196 (18.5%) had severe CAC. The MASLD and MAFLD prevalence rates were 32.6% and 45.2%, respectively, with an overlap of 30.7%. In an ASCVD risk score-adjusted model, both MASLD (adjusted odd ratios [aOR], 1.21; 95% confidence interval [CI], 1.02-1.44; p = 0.033) and MAFLD (aOR 1.20; 95% CI 1.01-1.42, p = 0.034) were associated with CAC, whereas only MASLD (aOR 1.38; 95% CI 1.01-1.89, p = 0.041) was associated with severe CAC. Compared to the reference group, the overlapping group showed an association with CAC (aOR 1.22; 95% CI 1.01-1.47; p = 0.038); however, the MASLD and MAFLD subgroups did not differ in their association with CAC. MASLD may predict a higher risk of ASCVD more effectively than MAFLD., (© 2024. The Author(s).)

The influence of thyroid hormone (TH) on liver metabolism has attracted the attention of pharmacologists seeking new treatments for metabolic dysfunction-associated steatotic liver disease (MASLD), an increasingly common metabolic disorder. In this context, the selective induction of autophagy by TH in preclinical models has been identified as a promising mechanism. In this process, TH clears intrahepatic fat through lipophagy while protecting against inflammation and mitochondrial damage in hepatocytes via mitophagy. Furthermore, TH-induced aggrephagy may represent a protective mechanism to mitigate the development of MASLD-associated hepatocellular carcinoma. Considering the defects in autophagy observed during the progression of human MASLD, the induction of autophagy by TH, its metabolites, and its analogs represent a novel strategy to combat hepatic damage across the MASLD spectrum.

Background: The use of livers with significant steatosis is associated with worse transplantation outcomes. Brain death donor liver acceptance is mostly based on subjective surgeon assessment of liver appearance, since steatotic livers acquire a yellowish tone. The aim of this study was to develop a rapid, robust, accurate, and cost-effective method to assess liver steatosis., Methods: From June 1, 2018, to November 30, 2023, photographs and tru-cut needle biopsies were taken from adult brain death donor livers at a single university hospital for the study. All the liver photographs were taken by smartphones then color calibrated, segmented, and divided into patches. Color and texture features were then extracted and used as input, and the machine learning method was applied. This is a collaborative project between Vall d'Hebron University Hospital and Barcelona MedTech, Pompeu Fabra University, and is referred to as LiverColor., Results: A total of 192 livers (362 photographs and 7240 patches) were included. When setting a macrosteatosis threshold of 30%, the best results were obtained using the random forest classifier, achieving an AUROC = 0.74, with 85% accuracy., Conclusion: Machine learning coupled with liver texture and color analysis of photographs taken with smartphones provides excellent accuracy for determining liver steatosis., (© 2024 The Author(s). Clinical Transplantation published by Wiley Periodicals LLC.)

Excessive caloric intake and obesity due to high-fat (HFD) and high-disaccharide (HDD) diets have been recognized as major contributing factors to dyslipidemia and metabolic dysfunction-associated steatotic liver disease (MASLD). However, the effect of HFD and HDD without excessive caloric intake is obscure. The aim of the study was to evaluate the effect of physiological caloric intake delivered through HFD and HDD on liver and lipid profiles. The study was performed on 6-week-old male and female (50/50%) Sprague Dawley rats, receiving either a standard (controls, n = 16), HFD (n = 14) or HDD (n = 14) chow. All groups received the same, standard daily calorie rations, titrated weekly to the age of growing rats, for 12 weeks. A panel of metabolic in vivo measurement were performed, followed by histological, biochemical and molecular biology assays on tissues harvested from sacrificed rats. There was no significant difference between the groups in body weight. In contrast to controls, HFD and HDD groups showed metabolic dysfunction-associated steatohepatitis (MASH) characterized by liver steatosis, inflammation, ballooning of hepatocytes and fibrosis. These changes were more pronounced in the HFD than in the HDD group. The HFD group showed significantly higher serum LDL than controls or HDD rats. Furthermore, the HFD group had higher liver protein levels of low-density lipoprotein receptor (LDLR) but lower plasma levels of proprotein convertase subtilisin/kexin type 9 (PCSK9) than the controls or HDD group. There were no differences between sexes in evaluated parameters. The excessive caloric intake and obesity are not prerequisites for the development of MASH and dyslipidemia in rats. The liver changes induced by the HFD and HDD diets exhibit differences in severity, as well as in the expression patterns of LDLR and PCSK9. Notably, these effects are independent of the sex of the rats., (© 2024. The Author(s).)

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-β-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., Competing Interests: Declaration of interests M.K. was a founder and stockholder in Elgia Pharmaceuticals and had received research support from Merck and Janssen Pharmaceuticals. P.C.D. consulted for DSM animal health in 2023; is an advisor and holds equity in Cybele, bileOmix, and Sirenas; and is a scientific co-founder and advisor and holds equity in Ometa, Enveda, and Arome, with prior approval by UC San Diego., (Published by Elsevier Inc.)

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 β-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 β-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 β-arrestin 2 depletion may be a potential approach for MASH., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024. Published by Elsevier Inc.)

Recent findings in glycobiology revealed direct evidence of the involvement of oligosaccharide changes in human diseases, including liver diseases. Fucosylation describes the attachment of a fucose residue to a glycan or glycolipid. We demonstrated that fucosylated proteins are useful serum biomarkers for nonalcoholic fatty liver disease. Among fucosyltransferases, expression of alpha-1, 6-fucosyltransferase (Fut8), which produces core fucose, is frequently elevated during the progression of human chronic liver diseases. Previously, we discovered core-fucose-specific Pholiota squarrosa lectin (PhoSL) from Japanese mushroom Sugitake. Lectins are bioactive compounds that bind to glycan specifically, and various kinds of lectin have a variety of biological functions. Using high-fat and high-cholesterol (HFHC)-fed steatohepatitic mice, we found that core fucosylation increases in hepatic inflammatory macrophages. Antibody drugs bind to specific antigens and block protein function. We hypothesized that, like antibody drugs, PhoSL could have inhibitory effects on glycoproteins involved in steatohepatitis progression. PhoSL administration dramatically decreased hepatic macrophage infiltration and liver fibrosis-related gene expression. Using mouse macrophage-like cell RAW264.7, we found that PhoSL enhanced core-fucose-mediated activation of macrophage cell death by blocking interferon-γ/signal transducer and activator of transcription 1 (STAT1) signaling. Core-fucose-mediated cell death is a mechanism for the anti-inflammatory effects and anti-fibrotic effects of PhoSL on activated macrophages in steatohepatitic liver. In addition, PhoSL provides an anti-fibrotic effect by blocking transforming growth factor-β/SMAD family member 3 signaling in hepatic stellate cells. In conclusion, we found core-fucose-specific PhoSL administration could suppress steatohepatitis progression by decreasing inflammatory macrophage infiltration and fibrotic signaling in hepatic stellate cells., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The presence of marked hepatic steatosis in patients with high alcohol consumption was first described in 1836 by Addison et al.1 Many years later, in 1980, Ludwig and colleagues described a histological picture very similar to that seen in patients with alcoholic hepatitis but who did not consume alcohol, coining the term non-alcoholic steatohepatitis (NASH).2 In recent years, the terminology used to describe conditions related to hepatic steatosis has undergone significant evolution. In 2020, Eslam et al.3 subsequently modified it to MAFLD (Metabolic Associated Fatty Liver Disease) to better reflect its association with metabolic dysfunction, a nomenclature that, from the beginning, generated some reluctance due to the absence of clear international consensus.

This study explores a combined strategy of Raman and reflectance spectroscopy for quantifying liver fat content and fat droplet size, crucial in assessing donor livers. By using Monte Carlo simulations and experimental setups with oil-in-water phantoms, our findings indicate that Raman scattering can solely differentiate between varying fat contents. At the same time, reflectance intensity is influenced by both fat content and oil droplet size, with a more pronounced sensitivity to fat droplet size. This study demonstrates the efficacy of combined Raman and reflectance spectroscopy in assessing liver steatosis and fat droplet size, potentially aiding in assessing donor livers for transplantation., (© 2024 The Author(s). Journal of Biophotonics published by Wiley‐VCH GmbH.)

Endoplasmic reticulum (ER) stress is a major cause of hepatic steatosis through increasing de novo lipogenesis. Forkhead box O6 (FoxO6) is a transcription factor mediating insulin signaling to glucose and lipid metabolism. Therefore, dysregulated FoxO6 is involved in hepatic lipogenesis. This study elucidated the role of FoxO6 in ER stress-induced hepatic steatosis in vivo and in vitro. Hepatic ER stress responses and β-oxidation were monitored in mice overexpressed with constitutively active FoxO6 allele and FoxO6-null mice. For the in vitro study, liver cells overexpressing constitutively active FoxO6 and FoxO6-siRNA were treated with high glucose, and lipid metabolism alterations were measured. ER stress-induced FoxO6 activation suppressed hepatic β-oxidation in vivo. The expression and transcriptional activity of peroxisome proliferator-activated receptor α (PPARα) were significantly decreased in the constitutively active FoxO6 allele. Otherwise, inhibiting β-oxidation genes were reduced in the FoxO6-siRNA and FoxO6-KO mice. Our data showed that the FoxO6-induced hepatic lipid accumulation was negatively regulated by insulin signaling. High glucose treatment as a hyperglycemia condition caused the expression of ER stress-inducible genes, which was deteriorated by FoxO6 activation in liver cells. However, high glucose-mediated ER stress suppressed β-oxidation gene expression through interactions between PPARα and FoxO6 corresponding to findings in the in vivo study-lipid catabolism is also regulated by FoxO6. Furthermore, insulin resistance suppressed b-oxidation through the interaction between FoxO6 and PPARα promotes hepatic steatosis, which, due to hyperglycemia-induced ER stress, impairs insulin signaling. KEY MESSAGES: Our original aims were to delineate the interrelation between the regulation of PPARα and the transcription factor FoxO6 pathway in relation to lipid metabolism at molecular levels. Evidence on high glucose promoted FoxO6 activation induced lipid accumulation in liver cells. The effect of PPARα activation of the insulin signaling. FoxO6 plays a pivotal role in hepatic lipid accumulation through inactivation of PPARα in FoxO6-overexpression mice., (© 2024. The Author(s).)

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent chronic liver disease worldwide. If left untreated, MASLD can progress from simple hepatic steatosis to metabolic dysfunction-associated steatohepatitis, which is characterized by inflammation and fibrosis. Current treatment options for MASLD remain limited, leaving substantial unmet medical needs for innovative therapeutic approaches. Here, we show that PLIN2, a lipid droplet protein inhibiting hepatic lipolysis, serves as a promising therapeutic target for MASLD. Hepatic PLIN2 levels were markedly elevated in multiple MASLD mouse models induced by diverse nutritional and genetic factors. The liver-specific deletion of Plin2 exhibited significant anti-MASLD effects in these models. To translate this discovery into a therapeutic application, we developed a GalNAc-siRNA conjugate with enhanced stabilization chemistry and validated its potent and sustained efficacy in suppressing Plin2 expression in mouse livers. This siRNA therapeutic, named GalNAc-siPlin2, was shown to be biosafe in mice. Treatment with GalNAc-siPlin2 for 6-8 weeks led to a decrease in hepatic triglyceride levels by approximately 60% in high-fat diet- and obesity-induced MASLD mouse models, accompanied with increased hepatic secretion of VLDL-triglyceride and enhanced thermogenesis in brown adipose tissues. Eight-week treatment with GalNAc-siPlin2 significantly improved hepatic steatosis, inflammation, and fibrosis in high-fat/high fructose-induced metabolic dysfunction-associated steatohepatitis models compared to control group. As a proof of concept, we developed a GalNAc-siRNA therapeutic targeting human PLIN2, which effectively suppressed hepatic PLIN2 expression and ameliorated MASLD in humanized PLIN2 knockin mice. Together, our results highlight the potential of GalNAc-siPLIN2 as a candidate MASLD therapeutic for clinical trials., Competing Interests: Conflict of interest A. J. Z., Y. W., M. L., Y. Z., and Q. Y. are named inventors of pending patent applications (2023106233979 to the Chinese Patent Office). The other authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Lifestyle intervention is the mainstay of therapy for metabolic dysfunction-associated steatohepatitis (MASH), and liver fibrosis is a key consequence of MASH that predicts adverse clinical outcomes. The placebo response plays a pivotal role in the outcome of MASH clinical trials. Second harmonic generation/two-photon excitation fluorescence (SHG/TPEF) microscopy with artificial intelligence analyses can provide an automated quantitative assessment of fibrosis features on a continuous scale called qFibrosis. In this exploratory study, we used this approach to gain insight into the effect of lifestyle intervention-induced fibrosis changes in MASH., Methods: We examined unstained sections from paired liver biopsies (baseline and end-of-intervention) from MASH individuals who had received either routine lifestyle intervention (RLI) (n = 35) or strengthened lifestyle intervention (SLI) (n = 17). We quantified liver fibrosis with qFibrosis in the portal tract, periportal, transitional, pericentral, and central vein regions., Results: About 20% (7/35) and 65% (11/17) of patients had fibrosis regression in the RLI and SLI groups, respectively. Liver fibrosis tended towards no change or regression after each lifestyle intervention, and this phenomenon was more prominent in the SLI group. SLI-induced liver fibrosis regression was concentrated in the periportal region., Conclusion: Using digital pathology, we could detect a more pronounced fibrosis regression with SLI, mainly in the periportal region. With changes in fibrosis area in the periportal region, we could differentiate RLI and SLI patients in the placebo group in the MASH clinical trial. Digital pathology provides new insight into lifestyle-induced fibrosis regression and placebo responses, which is not captured by conventional histological staging., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Magnetic resonance elastography (MRE) is recognized as the most precise imaging technology for assessing liver fibrosis in individuals with metabolic dysfunction-associated steatotic liver disease (MASLD). We aimed to investigate the clinical factors and pathological characteristics that may impact LSM in MASLD patients., Methods: This cross-sectional study recruited 124 patients who concurrently performed MRE, MRI-PDFF, and biopsy-proven MASLD. Linear regression models, Spearman's correlation, and subgroup analysis were employed to identify the variables affecting LSM., Results: The AUROC (95 % CI) of MRE for diagnosing fibrosis stage ≥ 1, 2, 3, and 4 was 0.80 (0.70-0.90), 0.76 (0.66-0.85), 0.92 (0.86-0.99), and 0.99 (0.99-1.00), with corresponding cutoffs of 2.56, 2.88, 3.35, and 4.76 kPa, respectively. Multivariate analyses revealed that AST was the only independent clinical variable significantly correlated with LSM. Furthermore, LSM exhibited a notable association with the grade of lobular inflammation and hepatocellular ballooning. Subgroup analysis showed that when AST ≥ 2 ULN or inflammation grade ≥ 2, LSM of patients with early fibrosis stages showed a slight but significant increase., Conclusion: MRE demonstrates significant diagnostic accuracy in predicting liver fibrosis stages for MASLD patients, especially for advanced liver fibrosis and cirrhosis. However, elevated AST and the severity of liver inflammation may impact its accuracy in staging early liver fibrosis., Competing Interests: Conflict of interest All authors of this manuscript have directly participated in planning, execution, and analysis of this study. And the contents of this manuscript are not now under consideration for publication elsewhere. None of the authors received honoraria or fees for their contribution to the development of this article or supplement., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)