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Since the role of the liver in metabolic dysfunction, including type 2 diabetes mellitus, was demonstrated, studies on non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) have shown associations between fatty liver disease and other metabolic diseases. Unlike the exclusionary diagnostic criteria of NAFLD, MAFLD diagnosis is based on the presence of metabolic dysregulation in fatty liver disease. Renaming NAFLD as MAFLD also introduced simpler diagnostic criteria. In 2023, a new nomenclature, steatotic liver disease (SLD), was proposed. Similar to MAFLD, SLD diagnosis is based on the presence of hepatic steatosis with at least one cardiometabolic dysfunction. SLD is categorized into metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related/-associated liver disease, alcoholrelated liver disease, specific etiology SLD, and cryptogenic SLD. The term MASLD has been adopted by a number of leading national and international societies due to its concise diagnostic criteria, exclusion of other concomitant liver diseases, and lack of stigmatizing terms. This article reviews the diagnostic criteria, clinical relevance, and differences among NAFLD, MAFLD, and MASLD from a diabetologist's perspective and provides a rationale for adopting SLD/MASLD in the Fatty Liver Research Group of the Korean Diabetes Association.

Background: Nonalcoholic fatty liver disease (NAFLD) is a chronic and progressive condition that afflicts patients of all ages, including neonates. Previously, we reported that neonatal pigs fed formulas rich in medium-chain (MCFA), compared with those fed formulas rich in long-chain fatty acid (LCFA) for 21 d, developed panacinar steatosis with no changes in whole-body adiposity., Objectives: The objective of this study was to examine the temporal onset and development of NAFLD in neonatal pigs in response to MCFA feeding., Methods: Neonatal pigs (n = 18) were fed isocaloric MCFA or LCFA formulas. Six pigs from each group were killed following 7, 14 or 21 d of feeding. Body composition was assessed before initiation and at the end of the feeding period using dual-energy X-ray absorptiometry. Liver fat content and liver morphologic features were determined from photomicrographs and evaluated for NAFLD by a pathologist., Results: Lean mass and fat mass as a percentage of body weight were not different between formulas. However, liver weight (P = 0.001) and liver fat mass (P < 0.001) were greater for pigs in the MCFA than those for pigs in the LCFA group. Steatosis developed as early as 7 d in the MCFA compared with the LCFA fed pigs (P < 0.001). In addition, steatosis progressed in a portal-to-venous direction as MCFA feeding duration increased (P = 0.02). Pigs diagnosed with NASH (P < 0.001) and greater nonalcoholic fatty liver disease scores were those in the MCFA group (P < 0.001)., Conclusions: These results suggest that the onset and progression of NAFLD from steatosis to nonalcoholic steatohepatitis occurs rapidly in response to MCFA feeding. Moreover, periportal steatosis is the initial feature in the development of NAFLD before its progression to nonalcoholic steatohepatitis. The development of NAFLD in neonates seems to occur independently of whole-body adiposity., Competing Interests: Conflict of interest The authors report no conflicts of interest., (Copyright © 2024 American Society for Nutrition. Published by Elsevier Inc. All rights reserved.)

Background: Recently, a panel of multi-society experts proposed steatotic liver disease (SLD) as an alternative terminology for metabolic dysfunction-associated fatty liver disease (MAFLD) or nonalcoholic fatty liver disease (NAFLD)., Aims: We compared the impact of SLD, subtype of SLD, MAFLD and NAFLD on all-cause and cause-specific mortality., Methods: A total of 7811 individuals in the third National Health and Nutrition Examination Survey and linked mortality through 2019 were analysed. SLD was defined based on ultrasonographic hepatic steatosis. SLD, subtype of SLD and MAFLD were defined using the proposed definitions. The Cox proportional hazard model assessed all-cause/cause-specific mortality., Results: During a median follow-up of 27.1 years, individuals with SLD and MAFLD experienced approximately 13%-23% higher risk of all-cause mortality (hazard ratio [HR]: 1.15, 95% confidence interval [CI]: 1.02-1.29 for SLD; HR: 1.23, 95% CI: 1.09-1.38 for MAFLD; HR: 1.13, 95% CI: 1.01-1.27 for metabolic dysfunction-associated steatotic liver disease [MASLD]). Individuals with MetALD demonstrated a higher risk of all-cause (HR: 1.68, 95% CI: 1.10-2.57) and cancer-related mortality (HR: 2.40, 95% CI: 1.23-4.66). MASLD with advanced fibrosis had an increased risk of all-cause mortality compared to MASLD without advanced fibrosis., Conclusions: SLD, especially MASLD and MetALD, is associated with increased all-cause mortality among adults in the US. Given this significant association between SLD or subtype of SLD (MASLD and MetALD) and all-cause mortality, adopting the proposed SLD criteria may help identify a sub-group of individuals with SLD who are at an increased risk for all-cause mortality., (© 2024 John Wiley & Sons Ltd.)

Type 2 Diabetes Mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD) are part of metabolic syndrome and share multiple causal associations. Both conditions have an alarmingly increasing incidence and lead to multiple complications, which have an impact on a variety of organs and systems, such as the kidneys, eyes, and nervous and cardiovascular systems, or may cause metabolic disruptions. Sodium-glucose cotransporter 2-inhibitors (SGLT2-i), as an antidiabetic class with well-established cardiovascular benefits, and its class members have also been studied for their presumed effects on steatosis and fibrosis improvement in patients with NAFLD or non-alcoholic steatohepatitis (NASH). The MEDLINE and Cochrane databases were searched for randomized controlled trials examining the efficacy of SGLT2-i on the treatment of NAFLD/NASH in patients with T2DM. Of the originally identified 179 articles, 21 articles were included for final data analysis. Dapagliflozin, empagliflozin, and canagliflozin are some of the most used and studied SGLT2-i agents which have proven efficacy in treating patients with NAFLD/NASH by addressing/targeting different pathophysiological targets/mechanisms: insulin sensitivity improvement, weight loss, especially visceral fat loss, glucotoxicity, and lipotoxicity improvement or even improvement of chronic inflammation. Despite the considerable variability in study duration, sample size, and diagnostic method, the SGLT2-i agents used resulted in improvements in non-invasive markers of steatosis or even fibrosis in patients with T2DM. This systematic review offers encouraging results that place the SGLT2-i class at the top of the therapeutic arsenal for patients diagnosed with T2DM and NAFLD/NASH.

Objectives: To investigate the correlations between physical activity (PA) and metabolic associated fatty liver disease (MAFLD) or metabolic dysfunction-associated steatotic liver disease (MASLD) within a substantial population-based survey, and to examine the association between PA and liver fibrosis (LF)., Methods: Data from the 2017-2020 NHANES cycle were utilized in this study. PA was divided into four types: leisure-time PA (LTPA), transportation-related PA (TPA), occupational PA (OPA) and total time PA (total PA, which is composed of OPA, TPA and LTPA). Weighted logistic regression models were performed to analyze the associations between PA and MAFLD/MASLD and LF. Mediation analysis was used to explore whether LTPA completely mediated the statistically significant relationship between total PA and MAFLD/MASLD or LF., Results: The study encompassed a sample size of 5897 participants aged 20 years and above, among the total participants, 2568 individuals with MAFLD and 2588 individuals with MASLD. There was no statistically significant correlation observed between OPA/TPA and MAFLD/MASLD and LF; however, active LTPA demonstrated an inverse association with MAFLD/MASLD (OR: 0.548; 95% CI: 0.458, 0.656/OR: 0.543; 95% CI: 0.453, 0.650), as well as a negative correlation with significant/advanced LF (OR: 0.457; 95% CI: 0.334,0.625/OR: 0.427; 95% CI: 0.295,0.619). There was also a significant inverse association between total PA and MAFLD/MASLD or LF, but this association was carried by the difference in LTPA., Conclusion: Participation in active LTPA is associated with a reduced likelihood of MAFLD/MASLD and LF, while neither OPA nor TPA can replace these effects of LTPA., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Background and Aims: Noninvasive tools assessing steatosis, such as ultrasonography-based 2D-attenuation imaging (ATI), are needed to tackle the worldwide burden of steatotic liver disease. This one-stage individual patient data (IPD) meta-analysis aimed to create an ATI-based steatosis grading system., Approach and Results: A systematic review (EMBASE + MEDLINE, 2018-2022) identified studies, including patients with histologically or magnetic resonance imaging proton-density fat fraction (MRI-PDFF)-verified ATI for grading steatosis (S0 to S3). One-stage IPD meta-analyses were conducted using generalized mixed models with a random study-specific intercept. Created ATI-based steatosis grading system (aS0 to aS3) was externally validated on a prospective cohort of patients with type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (n=174, histologically and MRI-PDFF-verified steatosis). Eleven enrolled studies included 1374 patients, classified into S0, S1, S2, and S3 in 45.4%, 35.0%, 9.3%, and 10.3% of the cases. ATI was correlated with histological steatosis ( r = 0.60; 95% CI: 0.52, 0.67; p < 0.001) and MRI-PDFF ( r = 0.70; 95% CI: 0.66, 0.73; p < 0.001) but not with liver stiffness ( r = 0.03; 95% CI: -0.04, 0.11, p = 0.343). Steatosis grade was an independent factor associated with ATI (coefficient: 0.24; 95% CI: [0.22, 0.26]; p < 0.001). ATI marginal means within S0, S1, S2, and S3 subpopulations were 0.59 (95% CI: [0.58, 0.61]), 0.69 (95% CI [0.67, 0.71]), 0.78 (95% CI: [0.76, 0.81]), and 0.85 (95% CI: [0.83, 0.88]) dB/cm/MHz; all contrasts between grades were significant ( p < 0.0001). Three ATI thresholds were calibrated to create a new ATI-based steatosis grading system (aS0 to aS3, cutoffs: 0.66, 0.73, and 0.81 dB/cm/MHz). Its external validation showed Obuchowski measures of 0.84 ± 0.02 and 0.82 ± 0.02 with histologically based and MRI-PDFF-based references., Conclusions: ATI is a reliable, noninvasive marker of steatosis. This validated ATI-based steatosis grading system could be valuable in assessing patients with metabolic dysfunction-associated steatotic liver disease., (Copyright © 2024 American Association for the Study of Liver Diseases.)

Background and Aim: New nomenclature of steatotic liver disease (SLD) including metabolic dysfunction-associated SLD (MASLD), MASLD and increased alcohol intake (MetALD), and alcohol-associated liver disease (ALD) has recently been proposed. We investigated clustering analyses to decipher the complex landscape of SLD pathologies including the former nomenclature of nonalcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD)., Methods: Japanese individuals who received annual health checkups including abdominal ultrasonography (n = 15 788, men/women: 10 250/5538, mean age: 49 years) were recruited., Results: The numbers of individuals with SLD, MASLD, MetALD, ALD, NAFLD, and MAFLD were 5603 (35.5%), 4227 (26.8%), 795 (5.0%), 324 (2.1%), 3982 (25.8%), and 4946 (31.3%), respectively. Clustering analyses using t-distributed stochastic neighbor embedding and K-means to visually represent interconnections in SLDs uncovered five cluster formations. MASLD and NAFLD mainly shared three clusters including (i) low alcohol intake with relatively low-grade obesity; (ii) obesity with dyslipidemia; and (iii) dysfunction of glucose metabolism. Both MetALD and ALD displayed one distinct cluster intertwined with alcohol consumption. MAFLD widely shared all of the five clusters. In machine learning-based analyses using algorithms of random forest and extreme gradient boosting and receiver operating characteristic curve analyses, fatty liver index (FLI), calculated by body mass index, waist circumference, and levels of γ-glutamyl transferase and triglycerides, was selected as a useful feature for SLDs., Conclusions: The new nomenclature of SLDs is useful for obtaining a better understanding of liver pathologies and for providing valuable insights into predictive factors and the dynamic interplay of diseases. FLI may be a noninvasive predictive marker for detection of SLDs., (© 2024 The Authors. Journal of Gastroenterology and Hepatology published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

(1) Background: Non-alcoholic fatty liver disease (NAFLD) is a major global health concern. The increasing prevalence of NAFLD has been related to type 2 diabetes mellitus (T2D). However, the relationship between short-chain fatty acids (SCFAs) and NAFLD severity is ambiguous in T2D subjects. This study aimed to explore the association of SCFAs with the severity of NAFLD in T2D patients. (2) Methods: We employed echography to examine the severity of hepatic steatosis. The serum levels of nine SCFAs, namely, formate, acetate, propionate, butyrate, isobutyrate, methylbutyrate, valerate, isovalerate, and methylvalerate, were measured using gas chromatography mass spectrometry. (3) Results: A total of 259 T2D patients was enrolled in this cross-sectional study. Of these participants, 117 with moderate to severe NAFLD had lower levels of formate, isobutyrate, and methylbutyrate than the 142 without NAFLD or with mild NAFLD. Lower circulating levels of isobutyrate and methylbutyrate were associated with an increased severity of NAFLD. A relationship between NAFLD severity and circulating isobutyrate and methylbutyrate levels was found independently of a glycated hemoglobin (HbA1C) level of 7.0%. (4) Conclusion: Circulating levels of isobutyrate and methylbutyrate were significantly and negatively correlated with NAFLD severity in the enrolled T2D patients. SCFAs may be related to NAFLD severity in T2D patients.

Competing Interests: Conflicts of interest The authors have no competing interests to declare.

Background/aims: Longitudinal studies assessing the impact of genetic polymorphisms on outcomes in patients with Type 2 Diabetes Mellitus (T2DM) and Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) are scarce. This study aimed to evaluate the effect of PNPLA3 and TM6SF2 risk alleles on hepatic and extrahepatic outcomes in T2DM-MASLD individuals., Methods: Patients' polymorphisms were analysed as follows: PNPLA3 CC, CG and GG; TM6SF2 CC and CT + TT; combined comparing no mutant allele, one allele G or T or ≥2 alleles G or T. Hierarchical models were built to assess associations between polymorphisms and outcomes, independently of confounding factors. Multivariate logistic regression was used for cirrhosis and its complications and extrahepatic cancer, and Cox regression for cardiovascular events (CVEs) and all-cause mortality., Results: In total, 407 T2DM-MASLD patients (62.1 ± 10.5 years, 67.6% women) were followed for 11 (6-13) years. Having at least one G or T allele independently increased the risk of cirrhosis in the separate analysis of PNPLA3 and TM6SF2. Combined polymorphism analysis demonstrated an even higher risk of cirrhosis if two or more risk alleles were present (OR 18.48; 95% CI 6.15-55.58; p < .001). Regarding cirrhosis complications, the risk was higher in PNPLA3 GG and TM6SF2 CT + TT, also with an even higher risk when two or more risk alleles were present in the combined evaluation (OR 27.20; 95% CI 5.26-140.62; p < .001). There were no associations with CVEs or mortality outcomes., Conclusion: In T2DM, PNPLA3 and TM6SF2 polymorphisms, individually and additively, impact MASLD severity, with an increased risk of cirrhosis and its complications., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: Increasing visceral fat deposition with raised prevalence of obesity and metabolic syndrome is associated with many adverse conditions, especially cardiovascular diseases and diabetes. Although there are many studies that investigate hepatic steatosis in hypothyroidism and subclinical hypothyroidism, to the best of our knowledge, there is no study investigating its relationship with pancreatic steatosis. In the present study, the purpose was to investigate this relationship., Methods: Physical and biochemical characteristics of 30 hypothyroid, 30 subclinical hypothyroid, and 30 euthyroid volunteers were recorded in this cross-sectional study. Liver and pancreatic steatosis were evaluated with ultrasonography., Results: It was found that pancreatic steatosis was increased in hypothyroid and subclinical groups when compared to the control group, and hepatic steatosis was increased in the subclinical group when compared to the control group (steatosis; p = 0.002, p = 0.004, p = 0.001, p = 0.002, p = 0.002, p = 0.004). Pancreatic steatosis was positively correlated with age, hepatic steatosis, height, weight, BMI, waist circumference, hip circumference, hemoglobin, Insulin, alanine aminotransferase, Triglyceride, Creatinine, and gamma-glutamyltransferase and was negatively correlated with total cholesterol, high-density lipoproteins., Conclusions: The prevalence of pancreatic steatosis was found to be increased in hypothyroidism and subclinical hypothyroidism when compared with the euthyroid control group., (© 2023 The Authors. Diabetes/Metabolism Research and Reviews published by John Wiley & Sons Ltd.)

Aims: People with type 2 diabetes mellitus are at increased risk of developing hepatic steatosis. We determined the prevalence of hepatic steatosis in middle-aged patients with and without diabetic retinopathy (DR) in an Indian population. We feel this information is critical, with trends of increasing chronic liver disease-related mortality at younger ages. Method: Institution-based analytical cross-sectional study with 114 middle-aged type 2 diabetes patients; 57 in each group with <15 years of duration of DM and without excessive drinking. Hepatic steatosis was determined by the hepatic steatosis index (HSI), hepatic ultrasonography (USG), and elastography. Result: The HSI in DR (37.9 ± 3.9) was more ( P  = 0.012) than in without diabetic retinopathy (NODR) (36.3 ± 3.3). There was no difference between two groups in liver span ( P  = 0.829) or in the prevalence of fatty liver ( P  = 0.562) as determined by conventional USG. Elastography value (kPa) was more ( P  = 0.001) in DR (6.51 ± 1.85) than in NODR (5.14 ± 1.60). On elastography, 50.9% in DR had a likelihood ratio (Metavir score for a stiffness value) for stage 2 Metavir score. In DR, 11.8% of those missed by USG had a likelihood ratio for ≥ stage 2 Metavir score on elastography. The presence of DR was independently correlated with kPa value ( P  < 0.001). Conclusion: A significantly higher prevalence of hepatic steatosis was observed in DR in this population. DR can be a useful biomarker for early hepatic screening in midlife, particularly with hepatic elastography, so that timely diagnosis of hepatic steatosis can be made.

Background & Aims: Concurrent hepatic steatosis has diverse effects on chronic hepatitis B (CHB), however the combined effects of metabolic dysfunction-associated steatotic liver disease (MASLD) and CHB on liver fibrosis progression remains unclear. The primary aim of this study was to utilize serial fibrosis measurements to compare the dynamic change in fibrosis in CHB patients with/without concurrent MASLD. The secondary aim was to investigate factors associated with steatosis development and regression in CHB patients., Methods: This was a retrospective cohort study of all non-cirrhotic CHB patients identified from 1/1/2011 to 31/12/2016. Hepatic steatosis was diagnosed by ultrasound. Fibrosis markers included liver stiffness (LSM) by transient elastography, APRI and FIB-4. General linear mixed effects modelling was used to fit polynomial and linear estimates., Results: Of 810 CHB patients (n = 2,373 LSM measurements; median age 44.4y; 48% male; 24% HBeAg positive), 14% had concurrent MASLD. LSM was higher at baseline but decreased in MASLD patients over time, while LSM remained stable in non-MASLD patients, such that all patients had similar LSM beyond 4-5 years. MASLD patients had lower APRI compared to non-MASLD patients, which was predominately due to a higher platelet count and higher ALT over time. There was substantial discordance between LSM, APRI and FIB-4. Baseline BMI was the only factor that predicted steatosis development and regression., Conclusions: We found no evidence of an association between concurrent MASLD and fibrosis progression amongst CHB patients without baseline advanced liver disease. APRI and FIB-4 may have reduced accuracy in MASLD patients., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Sex-based differences in obesity-related hepatic malignancies suggest the protective roles of estrogen. Using a preclinical model, we dissected estrogen receptor (ER) isoform-driven molecular responses in high-fat diet (HFD)-induced liver diseases of male and female mice treated with or without an estrogen agonist by integrating liver multi-omics data. We found that selective ER activation recovers HFD-induced molecular and physiological liver phenotypes. HFD and systemic ER activation altered core liver pathways, beyond lipid metabolism, that are consistent between mice and primates. By including patient cohort data, we uncovered that ER-regulated enhancers govern central regulatory and metabolic genes with clinical significance in metabolic dysfunction-associated steatotic liver disease (MASLD) patients, including the transcription factor TEAD1. TEAD1 expression increased in MASLD patients, and its downregulation by short interfering RNA reduced intracellular lipid content. Subsequent TEAD small molecule inhibition improved steatosis in primary human hepatocyte spheroids by suppressing lipogenic pathways. Thus, TEAD1 emerged as a new therapeutic candidate whose inhibition ameliorates hepatic steatosis., (© 2024. The Author(s).)

Competing Interests: Competing interests: PNB acknowledges consulting fees from Resolution Therapeutics and payment or honoraria from Takeda, outside of the submitted work. SZ-S has given presentations for and received support for attending meetings and/or travel from AbbVie, outside of the submitted work. AMA acknowledges grant support to her institution from the National Institutes of Health (NIH) (DK128127), Novo Nordisk, Pfizer and Target Pharma and advisory board participation for Novo Nordisk, outside of the submitted work. JFD has received research grants and lecture honoraria from MSD, AbbVie and Gilead, outside of the submitted work. JVL acknowledges grants and speaker fees from AbbVie, Gilead Sciences, MSD and Roche Diagnostics to his institution, speaker fees from Echosens, Janssen, Novo Nordisk and ViiV and consulting fees from Novavax, outside of the submitted work.

Aims: Given the increasing number of individuals developing metabolic dysfunction-associated steatotic liver disease (MASLD) and the low rate of those with progressive liver disease, there is a pressing need to conceive affordable biomarkers to assess MASLD in general population settings. Herein, we aimed to investigate the performance of the ultrasound-derived fat fraction (UDFF) for hepatic steatosis in high-risk individuals., Methods: A total of 302 Europeans with obesity, type 2 diabetes, or a clinical history of hepatic steatosis were included in the analyses. Clinical, laboratory, and imaging data were collected using standardized procedures during a single screening visit in Rome, Italy. Hepatic steatosis was defined by controlled attenuation parameter (CAP) or ultrasound-based Hamaguchi's score. UDFF performance for hepatic steatosis was estimated by the area under the receiver operating characteristic curve (AUC)., Results: Overall, median (IQR) UDFF was 12% (7-20). UDFF was positively correlated with CAP (ρ = 0.73, p < 0.0001) and Hamaguchi's score (ρ = 0.79, p < 0.0001). Independent predictors of UDFF were circulating triglycerides, alanine aminotransferase (ALT), and ultrasound-measured visceral adipose tissue (VAT). UDFF AUC was 0.89 (0.85-0.93) and 0.92 (0.88-0.95) for CAP- and ultrasound-diagnosed hepatic steatosis, respectively. UDFF AUC for hepatic steatosis was higher than those of fatty liver index (FLI), hepatic steatosis index (HSI), CAP-score (CAPS), and ALT (p < 0.0001). Lower age, ALT, and VAT were associated with discordance between UDFF and ultrasound., Conclusions: UDFF may be a simple and accurate imaging biomarker to assess hepatic steatosis and monitor changes in hepatic fat content over time or in response to therapeutic interventions beyond clinical trials., (© 2024 John Wiley & Sons Ltd.)

Metabolic dysfunction-associated steatotic liver disease (MASLD) and its advanced subtype, metabolic dysfunction-associated steatohepatitis (MASH), have emerged as the most common chronic liver disease worldwide, yet there is no targeted pharmacotherapy presently available. This study aimed to investigate the possible in vivo function of STE20-type protein kinase MST4, which was earlier implicated in the regulation of hepatocellular lipotoxic milieu in vitro, in the control of the diet-induced impairment of systemic glucose and insulin homeostasis as well as MASLD susceptibility. Whole-body and liver-specific Mst4 knockout mice were generated by crossbreeding conditional Mst4 fl/fl mice with mice expressing Cre recombinase under the Sox2 or Alb mice and their wild-type littermates were fed a high-fat or a methionine-choline-deficient (MCD) diet. Different in vivo tests were conducted in obese mice to describe the whole-body metabolism. MASLD progression in the liver and lipotoxic damage to adipose tissue, kidney, and skeletal muscle were analyzed by histological and immunofluorescence analysis, biochemical assays, and protein and gene expression profiling. In parallel, intracellular fat storage and oxidative stress were assessed in primary mouse hepatocytes, where MST4 was silenced by small interfering RNA. We found that global MST4 depletion had no effect on body weight or composition, locomotor activity, whole-body glucose tolerance or insulin sensitivity in obese mice. Furthermore, we observed no alterations in lipotoxic injuries to the liver, adipose, kidney, or skeletal muscle tissue in high-fat diet-fed whole-body Mst4 vs. wild-type mice. Liver-specific -/- mice and wild-type littermates displayed a similar severity of MASLD when subjected to an MCD diet, as evidenced by equal levels of steatosis, inflammation, hepatic stellate cell activation, fibrosis, oxidative/ER stress, and apoptosis in the liver. In contrast, the in vitro silencing of MST4 effectively protected primary mouse hepatocytes against ectopic lipid accumulation and oxidative cell injury triggered by exposure to fatty acids. In summary, these results suggest that the genetic ablation of MST4 in mice does not mitigate the initiation or progression of MASLD and has no effect on systemic glucose or insulin homeostasis in the context of nutritional stress. The functional compensation for the genetic loss of MST4 by yet undefined mechanisms may contribute to the apparent discrepancy between in vivo and in vitro phenotypic consequences of MST4 silencing.Mst4 -/- vs. wild-type mice. Liver-specific Mst4 -/- mice and wild-type littermates displayed a similar severity of MASLD when subjected to an MCD diet, as evidenced by equal levels of steatosis, inflammation, hepatic stellate cell activation, fibrosis, oxidative/ER stress, and apoptosis in the liver. In contrast, the in vitro silencing of MST4 effectively protected primary mouse hepatocytes against ectopic lipid accumulation and oxidative cell injury triggered by exposure to fatty acids. In summary, these results suggest that the genetic ablation of MST4 in mice does not mitigate the initiation or progression of MASLD and has no effect on systemic glucose or insulin homeostasis in the context of nutritional stress. The functional compensation for the genetic loss of MST4 by yet undefined mechanisms may contribute to the apparent discrepancy between in vivo and in vitro phenotypic consequences of MST4 silencing.

More than one-third of the adult world population has steatotic liver disease (SLD), with a few percent of individuals developing cirrhosis after decades of silent liver fibrosis accumulation. Lack of systematic early detection causes most patients to be diagnosed late, after decompensation, when treatment has limited effect and survival is poor. Unfortunately, no isolated screening test in primary care can sufficiently predict advanced fibrosis from SLD. Recent efforts, therefore, combine several parameters into screening algorithms, to increase diagnostic accuracy. Besides patient selection, for example, by specific characteristics, algorithms include nonpatented or patented blood tests and liver stiffness measurements using elastography-based techniques. Algorithms can be composed as a set of sequential tests, as recommended by most guidelines on primary care pathways. Future use of algorithms that are easy to interpret, cheap, and semiautomatic will improve the management of patients with SLD, to the benefit of global health care systems., Competing Interests: M.T. reports speaker fees from Echosens, Siemens Healthcare, Norgine, Madrigal, Takeda, AstraZeneca and Tillotts Pharma; advisory fees from Boehringer Ingelheim, GE Healthcare, and GSK; she is co-founder and board member of the company Evido, and board member of Alcohol & Society, a nongovernmental organization. K.P.L. reports speaker fees from Siemens Healthcare, consulting fees from Novo Nordisk, and is co-founder and board member of Evido. L.C. reports lecture fees from Echosens, Gilead, Inventiva, and Novo Nordisk, and advisory fees from Echosens, Gilead, Madrigal, MSD, Novo Nordisk, Pfizer, and Sagimet. K.T.B. has no conflicts of interest., (Thieme. All rights reserved.)

Metabolic dysfunction-associated steatohepatitis (MASH) is a major cause of liver-related morbidity and mortality, yet treatment options are limited. Manual scoring of liver biopsies, currently the gold standard for clinical trial enrollment and endpoint assessment, suffers from high reader variability. This study represents the most comprehensive multisite analytical and clinical validation of an artificial intelligence (AI)-based pathology system, AI-based measurement of metabolic dysfunction-associated steatohepatitis (AIM-MASH), to assist pathologists in MASH trial histology scoring. AIM-MASH demonstrated high repeatability and reproducibility compared to manual scoring. AIM-MASH-assisted reads by expert MASH pathologists were superior to unassisted reads in accurately assessing inflammation, ballooning, MAS ≥ 4 with ≥1 in each score category and MASH resolution, while maintaining non-inferiority in steatosis and fibrosis assessment. These findings suggest that AIM-MASH could mitigate reader variability, providing a more reliable assessment of therapeutics in MASH clinical trials., Competing Interests: Competing interests: H.P., H.H., A.S.-M., R.E., N.P., A.H.B. and N.P.A. are full-time, salaried employees of PathAI. K.E.W. was a full-time employee of PathAI during all phases of the study and is now a paid consultant of PathAI. S.A.H. is a paid consultant for Akero Therapeutics, Aligos Therapeutics, Altimmune, Boehringer Ingelheim, Bluejay Therapeutics, Echosens North America, Galecto, Gilead Sciences, GlaxoSmithKline, Hepion Pharmaceuticals, Hepta Bio, HistoIndex, Kriya Therapeutics, Madrigal Pharmaceuticals, Medpace, MGGM Therapeutics, NeuroBo Pharmaceuticals, Northsea Therapeutics, Novo Nordisk, Pfizer, Sagimet Biosciences, Terns and Viking Therapeutics and a shareholder of Akero, Cirius Therapeutics, Galectin Therapeutics, HistoIndex and Northsea Therapeutics. S.S.M., M.C.V., L.C.M., S.P.M.C., S.H.M., C.E.T. and M.C.M. were PathAI employees at the time of study conduct. J.G. and M.R. are paid contractors of PathAI. R.P.M. and G.M.S. are full-time, salaried employees of OrsoBio. C.C. is a full-time, salaried employee of Inipharm. S.D.P. is a full-time salaried employee of Gilead Sciences. A.-S.S. is a full-time, salaried employee of Novo Nordisk. A.M. was a paid consultant for Bristol Myers Squibb. V.B. is a full-time, salaried employee of Bristol Myers Squibb. A.J.S. has stock options in Genfit, Akarna, Tiziana, Indalo, Durect Inversago and Galmed; is a consultant to AstraZeneca, Nimbus, Takeda, Janssen, Gilead, Terns, Merck, Boehringer Ingelheim, Bristol Myers Squibb, Lilly, Novartis, Novo Nordisk, Pfizer and Genfit; and has been an unpaid consultant to Intercept, Echosens, Immuron, Galectin and Affimune Prosciento. His institution has received grant support from Gilead, Bristol Myers Squibb, Intercept, Merck, AstraZeneca and Novartis. He receives royalties from Elsevier and UptoDate. Q.M.A. is a coordinator of the EU IMI-2 LITMUS consortium, which is funded by the EU Horizon 2020 program and the EFPIA. This multistakeholder consortium includes industry partners. He has research grant funding from AstraZeneca, Boehringer Ingelheim and Intercept. He is a consultant on behalf of Newcastle University to Alimentiv, Akero, AstraZeneca, 89bio, Boehringer Ingelheim, Bristol Myers Squibb, Galmed, Genfit, Genentech, Gilead, GlaxoSmithKline, HistoIndex, Intercept, Inventiva, QVIA, Janssen, Madrigal, Merck, NGM Bio, Novartis, Novo Nordisk, PathAI, Pfizer, PharmaNest, Prosciento, Roche and Terns. He is a speaker for Novo Nordisk, Madrigal and Springer Healthcare and receives royalties from Elsevier. R.L. is a consultant to Aardvark Therapeutics, Altimmune, Alnylam–Regeneron, Amgen, Arrowhead Pharmaceuticals, AstraZeneca, Bluejay Therapeutics, Bristol Myers Squibb, Eli Lilly, Galmed, Gilead, Inipharma, Intercept, Inventiva, Ionis, Janssen, Madrigal, NGM Biopharmaceuticals, Novartis, Novo Nordisk, Merck, Pfizer, Sagimet, Theratechnologies, 89bio, Terns Pharmaceuticals and Viking Therapeutics. He is a cofounder of LipoNexus. V.R. is a paid consultant for Novo Nordisk, Northsea Madrigal, Enyo, Poxel, Bristol Myers Squibb, Intercept, NGM Bio and Sagimet., (© 2024. The Author(s).)

Background: The new nomenclature of metabolic dysfunction-associated steatotic liver disease (MASLD) substituting nonalcoholic fatty liver disease was proposed along with a new category of MASLD with increased alcohol intake (MetALD)., Aims: We aimed to explore the cancer risk by MASLD and MetALD., Methods: This nationwide cohort study included 3,596,709 participants who underwent a health check-up in 2011 in South Korea. Steatotic liver disease (SLD) was defined as a fatty liver index ≥30. Participants were categorized into four exclusive groups: MASLD, MetALD, other combination aetiology and no SLD. The subdistribution hazard ratio (SHR) was calculated using the Fine-Gray model after adjusting other variables., Results: During the 33.9 million person-years of follow-up, 285,845 participants (7.9%) developed cancers. Compared with no SLD, MASLD, MetALD and other combination aetiology had an increased risk of all cancer. Liver cancer risk escalated from no SLD to MASLD (SHR, 1.16; 95% CI, 1.12-1.21), MetALD (SHR, 2.06; 95% CI, 1.92-2.20) and other combination aetiology (SHR, 8.16; 95% CI, 7.69-8.67). Gastrointestinal cancers including oesophagus, stomach, colorectal, biliary and pancreas cancers increased in MASLD (SHR, 1.13; 95% CI, 1.11-1.15), MetALD (SHR, 1.17; 95% CI, 1.14-1.21) and other combination aetiology (SHR, 1.09; 95% CI, 1.05-1.13). A modest increase in lung cancer and hormone-sensitive cancer was observed with MASLD., Conclusions: This study showed that MASLD and MetALD are associated with an increased risk of cancer, particularly liver and gastrointestinal cancers. The findings build new evidence for the clinical outcomes of MetALD while highlighting the importance of managing alcohol intake properly in MASLD and MetALD., (© 2024 The Author(s). Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd.)

The primary objective of this study was to examine the association between iron overload (IO), metabolic dysfunction-associated steatotic liver disease (MASLD), and hepatic fibrosis. We hypothesized that there is a significant association. Data from the NHANES (2017-2020) were analyzed to explore IO's impact on MASLD and hepatic fibrosis in U.S. adults. We assessed serum ferritin, controlled attenuation parameter (CAP), liver stiffness measurement (LSM), and various covariates. Gene expression data were sourced from the FerrDb V2 and GEO databases. Differential gene expression analysis, Protein-Protein Interaction (PPI) Network construction, and Gene Ontology (GO) and KEGG pathway enrichment analyses were performed. The study verified the link between MASLD, hepatic fibrosis, and iron overload hub genes. This study of 5927 participants, averaging 46.78 years of age, revealed significant correlations between serum ferritin and CAP, LSM, after adjusting for covariates. Threshold effect analysis indicated nonlinear associations between serum ferritin and CAP, LSM, with distinct patterns observed by age and gender. Moreover, the area under the ROC curve for serum ferritin with MASLD and hepatic fibrosis was 0.8272 and 0.8376, respectively, demonstrating its performance in assessing these conditions. Additionally, molecular analyses identified potential hub genes associated with iron overload and MASLD, and hepatic fibrosis, revealing the underlying mechanisms. Our study findings reveal an association between iron overload, MASLD, and hepatic fibrosis. Additionally, the hub genes may be implicated in iron overload and subsequently contribute to the progression of MASLD and hepatic fibrosis. These findings support precision nutrition strategies., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: Metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are characterized by excessive triglyceride accumulation in the liver. However, due to an incomplete understanding of its pathogenesis, more efforts are needed to identify specific and effective treatments. N4-acetylcytidine (ac4C) is a newly discovered RNA modification to regulate mRNA. N-acetyltransferase 10 (NAT10) has not been fully explored in MASLD and MASH., Methods: The clinical relevance of NAT10 was evaluated based on its expression in various mouse and human models of MASLD and MASH. Acetylated RNA immunoprecipitation sequencing and mRNA stability assays were used to explore the role of NAT10 in regulating ac4C modification and expression of target genes. Genetically engineered mice were employed to investigate the role of NAT10 in MASLD and MASH progression., Results: Hepatic NAT10 expression was significantly increased in multiple mice and humans of MASLD and MASH. Genetic knockout of NAT10 protected mice from diet-induced hepatic steatosis and steatohepatitis, whereas overexpression of NAT10 exacerbated high-fat-diet-induced liver steatosis. Mechanistically, NAT10 binds to Srebp-1c mRNA, promoting its stability and expression, thereby upregulating lipogenic enzymes. Treatment with Remodelin, a NAT10-specific inhibitor, effectively ameliorates liver steatosis and dyslipidemia in a preclinical mouse model., Conclusions: Our findings indicate that NAT10 could regulate lipid metabolism in MASLD and MASH by stabilizing Srebp-1c mRNA and upregulating lipogenic enzymes. This study highlights the role of NAT10 and RNA acetylation in the pathogenesis of MASLD and MASH. Thus, our findings suggest a promising new therapeutic approach, such as the use of NAT10 inhibitor, for treating metabolic liver disease., Competing Interests: Declaration of competing interest No potential conflicts of interest relevant to this article were reported., (Copyright © 2024 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

Background and Aims: Metabolic dysfunction-associated steatotic liver disease (MASLD) is a leading indication for liver transplantation (LT), but also occurs after LT. The prevalence of de novo MASLD (dnMASLD) after LT, based on both surveillance (svLbx) and indication biopsies (indLbx), is unknown. Furthermore, the impact of the distinct cardiometabolic risk factors on histological disease activity has not been assessed. We aimed to evaluate the prevalence of dnMASLD and the association between the cardiometabolic risk factors and histological disease activity., Methods: We performed a retrospective single-center study in a LT cohort with indLbx and svLbx. Patients with NAFLD before LT were excluded., Results: We analyzed 249 patients who underwent either svLbx or indLbx. Forty-eight (19.2%) had either dnMASLD (n = 26/249, 10.4%) or metabolic dysfunction associated steatohepatitis (dnMASH) (n = 22/249, 8.8%). Although dnMASLD/dnMASH was more frequent in indLbx (35.1%, p < 0.01), still 16.5% of patients with svLbx had dnMASLD/dnMASH. While overweight (p < 0.01) and diabetes (p = 0.01) were more frequent in patients with dnMASH, only overweight was associated with histological disease activity in the multivariate analysis. No impact of dnMASLD on the overall survival was observed., Conclusion: While dnMASLD is more frequent in patients with indLBX, it also occurs in 16.5% of patients without signs of graft dysfunction. Overweight has the strongest impact on histological disease activity and should be monitored carefully after LT., (© 2024 The Author(s). Clinical Transplantation published by Wiley Periodicals LLC.)

Objective: To validate the proton density fat fraction (PDFF) obtained by the MRQuantif software from 2D chemical shift encoded MR (CSE-MR) data in comparison with the histological steatosis data., Methods: This study, pooling data from 3 prospective studies spread over time between January 2007 and July 2020, analyzed 445 patients who underwent 2D CSE-MR and liver biopsy. MR derived liver iron concentration (MR-LIC) and PDFF was calculated using the MRQuantif software. The histological standard steatosis score (SS) served as reference. In order to get a value more comparable to PDFF, histomorphometry fat fraction (HFF) were centrally determined for 281 patients. Spearman correlation and the Bland and Altman method were used for comparison., Results: Strong correlations were found between PDFF and SS (r s  = 0.84, p < 0.001) or HFF (r s  = 0.87, p < 0.001). Spearman's coefficients increased to 0.88 (n = 324) and 0.94 (n = 202) when selecting only the patients without liver iron overload. The Bland and Altman analysis between PDFF and HFF found a mean bias of 5.4% ± 5.7 [95% CI 4.7, 6.1]. The mean bias was 4.7% ± 3.7 [95% CI 4.2, 5.3] and 7.1% ± 8.8 [95% CI 5.2, 9.0] for the patients without and with liver iron overload, respectively., Conclusion: The PDFF obtained by MRQuantif from a 2D CSE-MR sequence is highly correlated with the steatosis score and very close to the fat fraction estimated by histomorphometry. Liver iron overload reduced the performance of steatosis quantification and joint quantification is recommended. This device-independent method can be particularly useful for multicenter studies., Clinical Relevance Statement: The quantification of liver steatosis using a vendor-neutral 2D chemical-shift MR sequence, processed by MRQuantif, is well correlated to steatosis score and histomorphometric fat fraction obtained from biopsy, whatever the magnetic field and the MR device used., Key Points: • The PDFF measured by MRQuantif from 2D CSE-MR sequence data is highly correlated to hepatic steatosis. • Steatosis quantification performance is reduced in case of significant hepatic iron overload. • This vendor-neutral method may allow consistent estimation of PDFF in multicenter studies., (© 2023. The Author(s), under exclusive licence to European Society of Radiology.)

Purpose: Metabolic dysfunction-associated steatohepatitis (MASH) is a liver disease that has gained widespread attention globally. Unfortunately, there is no approved treatment for this condition yet. However, recent research has identified Apoptosis signal-regulating kinase 1 (ASK1) and thyroid hormone receptor-β (THR-β) as potential targets for treating MASH. Although the individual effects of these two targets have been studied, their combinatory effect has not been well defined. Therefore, further research is needed to investigate the potential benefits of targeting both ASK1 and THR-β for treating MASH., Methods: We established a MASH model using the HFHFrC diet (high fat, high fructose, and cholesterol) and carbon tetrachloride (CCL4). Forty mice were evenly assigned to four groups: vehicle, GS4997 (an ASK1 inhibitor), MGL3196 (a THRβ agonist), GS4997+ MGL3196 combination (combo). The drugs were administered for 8 weeks, after which the mice were sacrificed for serum biochemical tests, liver TG and TC evaluation, liver histopathological study, and gene expression validation., Results: GS4997 and MGL3196, when used in combination, have been shown to have synergistic effects on various parameters. Firstly, they synergistically reduced body weight and liver body weight ratio. Secondly, this combination also synergistically lowered AST and TC. Thirdly, synergistic effects were also observed in liver TG and TC reduction. Fourthly, we further confirmed that GS4997 mildly improved liver inflammation, ballooning, and fibrosis, but exhibited incredible histopathological efficacy when combined with MGL3196. Finally, this combinatory effect can be interpreted by synergistically regulating lipid-related genes such as Dio1, Ctp1-α, and Cat, inflammation-related genes such as Il-6, Il-8, and Mcp-1, and fibrosis-related genes such as Tgf-β, Col1α1, and Col6α3., Conclusion: GS4997 and MGL3196, when used in combination, have been shown to have a comprehensive effect on MASH by synergistically regulating lipid, inflammation, and fibrosis-related gene expression through co-targeting ASK1 and THRβ., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Limited population-based studies discuss the association between fat mass index (FMI) and the risk of liver diseases. This investigation utilized data from the National Health and Nutrition Examination Survey (NHANES) to examine the linkage between the FMI and liver conditions, specifically steatosis and fibrosis. The study leveraged data from NHANES's 2017-2018 cross-sectional study, employing an oversampling technique to deal with sample imbalance. Hepatic steatosis and fibrosis were identified by vibration-controlled transient elastography. Receiver operating curve was used to assess the relationship of anthropometric indicators, e.g., the FMI, body mass index (BMI), weight-adjusted-waist index (WWI), percentage of body fat (BF%), waist-to-hip ratio (WHR), and appendicular skeletal muscle index (ASMI), with hepatic steatosis and fibrosis. In this study, which included 2260 participants, multivariate logistic regression models, stratified analyses, restricted cubic spline (RCS), and sharp regression discontinuity analyses were utilized. The results indicated that the WHR and the FMI achieved the highest area under the curve for identifying hepatic steatosis and fibrosis, respectively (0.720 and 0.726). Notably, the FMI presented the highest adjusted odds ratio for both hepatic steatosis (6.40 [4.91-8.38], p = 2.34e-42) and fibrosis (6.06 [5.00, 7.37], p = 5.88e-74). Additionally, potential interaction effects were observed between the FMI and variables such as the family income-to-poverty ratio, smoking status, and hypertension, all of which correlated with the presence of liver fibrosis (p for interaction < 0.05). The RCS models further confirmed a significant positive correlation of the FMI with the controlled attenuation parameter and liver stiffness measurements. Overall, the findings underscore the strong link between the FMI and liver conditions, proposing the FMI as a potential straightforward marker for identifying liver diseases., (© 2024. The Author(s).)

Metabolic dysfunction-associated steatohepatitis (MASH) is always accompanied with hepatic fibrosis that could potentially progress to liver cirrhosis and hepatocellular carcinoma. Employing a rat model, we evaluated the role of human placental extract (HPE) to arrest the progression of hepatic fibrosis to cirrhosis in patients with MASH. SHRSP5/Dmcr rats were fed with a high-fat and high-cholesterol diet for 4 weeks and evaluated for the development of steatosis. The animals were divided into control and treated groups and received either saline or HPE (3.6 ml/kg body weight) subcutaneously thrice a week. A set of animals were killed at the end of 6th, 8th, and 12th weeks from the beginning of the experiment. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), hepatic malondialdehyde (MDA), and glutathione content were measured. Immunohistochemical staining was performed for α-smooth muscle actin (α-SMA), 4-hydroxy-2-nonenal (4-HNE), collagen type I, and type III. Control rats depicted progression of liver fibrosis at 6 weeks, advanced fibrosis and bridging at 8 weeks, and cirrhosis at 12 weeks, which were significantly decreased in HPE-treated animals. Treatment with HPE maintained normal levels of MDA and glutathione in the liver. There was marked decrease in the staining intensity of α-SMA, 4-HNE, and collagen type I and type III in HPE treated rats compared with control animals. The results of the present study indicated that HPE treatment mediates immunotropic, anti-inflammatory, and antioxidant responses and attenuates hepatic fibrosis and early cirrhosis. HPE depicts therapeutic potential to arrest the progression of MASH towards cirrhosis., (© 2024 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Metabolic-dysfunction-associated steatotic liver disease (MASLD) is a prevalent clinical condition associated with elevated morbidity and mortality rates. Patients with MASLD treated with semaglutide, a glucagon-like peptide-1 receptor agonist, demonstrate improvement in terms of liver damage. However, the mechanisms underlaying this beneficial effect are not yet fully elucidated. We investigated the efficacy of semaglutide in halting MASLD progression using a genetic mouse model of diabesity. Leptin-receptor-deficient mice with obesity and diabetes (BKS db/db) were either untreated or administered with semaglutide for 11 weeks. Changes in food and water intake, body weight and glycemia were monitored throughout the study. Body fat composition was assessed by dual-energy X-ray absorptiometry. Upon sacrifice, serum biochemical parameters, liver morphology, lipidomic profile and liver-lipid-related pathways were evaluated. The semaglutide-treated mice exhibited lower levels of glycemia, body weight, serum markers of liver dysfunction and total and percentage of fat mass compared to untreated db/db mice without a significant reduction in food intake. Histologically, semaglutide reduced hepatic steatosis, hepatocellular ballooning and intrahepatic triglycerides. Furthermore, the treatment ameliorated the hepatic expression of de novo lipogenesis markers and modified lipid composition by increasing the amount of polyunsaturated fatty acids. The administration of semaglutide to leptin-receptor-deficient, hyperphagic and diabetic mice resulted in the amelioration of MASLD, likely independently of daily caloric intake, suggesting a direct effect of semaglutide on the liver through modulation of the lipid profile.

Competing Interests: NS has participated in Scientific Advisory Boards of Allergan, Intercept Pharma, MSD, Pfizer, Novo Nordisk, Gilead, Genkyotex, Astra-Zeneca, Boehringer Ingelheim, Sanofi, as well as clinical trials of AstraZeneca, Boehringer Ingelheim, Sanofi, DSM Nutritional Products and Roche Diagnostics. MR has participated in Scientific Advisory Boards of BMS, Boehringer Ingelheim Pharma, Eli Lilly, Fishawack Group, Gilead Sci., Novo Nordisk, Prosciento Inc., Sanofi, Target RWE, Terra Firma as well as clinical trials of Boehringer Ingelheim, Nutricia/Danone and Novartis.

The post-hoc study, derived from our previous prospective observational study, investigated the association between fasting serum proinsulin levels and hepatic steatosis in people with type 2 diabetes. The severity of hepatic steatosis was assessed using the fatty liver index. A total of 268 participants were divided into three groups: low (n = 110), moderate (n = 75), and high fatty liver index (n = 83). In both the crude and age/sex-adjusted analysis, logarithm-transformed proinsulin was significantly higher in the high fatty liver index group than in the low or moderate groups (all p < 0.01). The moderate fatty liver index group showed higher logarithm-transformed proinsulin than the low group (both p < 0.01). Positive associations between proinsulin and fatty liver index shown in this study would support an involvement of hepato-pancreatic crosstalk in the pathophysiology of type 2 diabetes.

Background: Obesity and type 2 diabetes frequently have metabolic dysfunction-associated steatotic liver disease (MASLD) including steatohepatitis (MASH). In obesity, the liver may adapt its oxidative capacity, but the role of mitochondrial turnover in MASLD remains uncertain., Methods: This cross-sectional study compared individuals with class III obesity (n = 8/group) without (control, OBE CON; NAFLD activity score: 0.4 ± 0.1) or with steatosis (OBE MASL, 2.3 ± 0.4), or MASH (OBE MASH, 5.3 ± 0.3, p < 0.05 vs. other groups). Hepatic mitochondrial ultrastructure was assessed by transmission electron microscopy, mitochondrial respiration by high-resolution respirometry, biomarkers of mitochondrial quality control and endoplasmic reticulum (ER) stress by Western Blot., Results: Mitochondrial oxidative capacity was 31 % higher in OBE MASL, but 25 % lower in OBE MASH (p < 0.05 vs. OBE CON). OBE MASH showed ~1.5fold lower mitochondrial number, but ~1.2-1.5fold higher diameter and area (p < 0.001 vs. other groups). Biomarkers of autophagy (p62), mitophagy (PINK1, PARKIN), fission (DRP-1, FIS1) and fusion (MFN1/2, OPA1) were reduced in OBE MASH (p < 0.05 vs. OBE CON). OBE MASL showed lower p62, p-PARKIN/PARKIN, and p-DRP-1 (p < 0.05 vs. OBE CON). OBE MASL and MASH showed higher ER stress markers (PERK, ATF4, p-eIF2α-S51/eIF2α; p < 0.05 vs. OBE CON). Mitochondrial diameter associated inversely with fusion/fission biomarkers and with oxidative capacity, but positively with H 2 O 2 ., Conclusion: Humans with hepatic steatosis already exhibit impaired mitochondrial turnover, despite upregulated oxidative capacity, and evidence for ER stress. In MASH, oxidative stress likely mediates progressive decline of mitochondrial turnover, ultrastructure and respiration indicating that mitochondrial quality control is key for energy metabolism and may have potential for targeting MASH. ClinGovTrial:NCT01477957., Competing Interests: Declaration of competing interest M.R. received personal fees from Allergan, Astra-Zeneca, Boehringer-Ingelheim, Eli Lilly, Fishawack Group, Gilead Sciences, Novo Nordisk, Pfizer, Prosciento and Target RWE and investigator-initiated research support from Boehringer-Ingelheim, Nutricia/Danone and Sanofi-Aventis. All other authors declare that there are no relationships or activities that might bias, or be perceived to bias, their work., (Copyright © 2023 Elsevier Inc. All rights reserved.)