ABSTRACT
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a complex multifactorial disease and becoming the leading cause of liver-related morbidity and mortality. MASLD spans from isolated steatosis to metabolic dysfunction-associated steatohepatitis (MASH), that may progress to cirrhosis and hepatocellular carcinoma (HCC). Genetic, metabolic, and environmental factors strongly contribute to the heterogeneity of MASLD. Lifestyle intervention and weight loss represent a viable treatment for MASLD. Moreover, Resmetirom, a thyroid hormone beta receptor agonist, has recently been approved for MASLD treatment. However, most individuals treated did not respond to this therapeutic suggesting the need for a more tailored approach to treat MASLD. Oligonucleotide-based therapies, namely small-interfering RNA (siRNA) and antisense oligonucleotide (ASO), have been recently developed to tackle MASLD by reducing the expression of genes influencing MASH progression, such as PNPLA3 and HSD17B13. Here, we review the latest progress made in the synthesis and development of oligonucleotide-based agents targeting genetic determinants of MASH.
ABSTRACT
BACKGROUND: With the implementation of the 11th edition of the International Classification of Diseases (ICD-11) and the publication of the metabolic dysfunction-associated fatty liver disease (MAFLD) nomenclature in 2020, it is important to establish consensus for the coding of MAFLD in ICD-11. This will inform subsequent revisions of ICD-11. METHODS: Using the Qualtrics XM and WJX platforms, questionnaires were sent online to MAFLD-ICD-11 coding collaborators, authors of papers, and relevant association members. RESULTS: A total of 890 international experts in various fields from 61 countries responded to the survey. We also achieved full coverage of provincial-level administrative regions in China. 77.1% of respondents agreed that MAFLD should be represented in ICD-11 by updating NAFLD, with no significant regional differences (77.3% in Asia and 76.6% in non-Asia, p = 0.819). Over 80% of respondents agreed or somewhat agreed with the need to assign specific codes for progressive stages of MAFLD (i.e. steatohepatitis) (92.2%), MAFLD combined with comorbidities (84.1%), or MAFLD subtypes (i.e., lean, overweight/obese, and diabetic) (86.1%). CONCLUSIONS: This global survey by a collaborative panel of clinical, coding, health management and policy experts, indicates agreement that MAFLD should be coded in ICD-11. The data serves as a foundation for corresponding adjustments in the ICD-11 revision.
Subject(s)
International Classification of Diseases , Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/epidemiology , Non-alcoholic Fatty Liver Disease/classification , Surveys and Questionnaires , Global HealthABSTRACT
CONTEXT: Metabolic dysfunction-associated steatotic liver disease (MASLD) is currently the most common chronic liver disease worldwide and is strongly associated with metabolic comorbidities, including dyslipidemia. OBJECTIVE: Herein, we aim to estimate the prevalence of MASLD and metabolic dysfunction-associated steatohepatitis (MASH) in Europeans with isolated hypercholesterolemia and isolated hypertriglyceridemia in the UK Biobank and to estimate the independent contribution of lipoproteins to liver triglyceride content. METHODS: We selected 218,732 Europeans from the UK Biobank without chronic viral hepatitis and other causes of liver disease, of whom 14,937 with liver magnetic resonance imaging (MRI) data available. Next, to examine the relationships between traits in predicting liver triglyceride content, we compared the predictive performance of several machine learning methods and selected the best performing algorithms based on the minimum cross-validated mean squared error (MSE). RESULTS: There was an approximately 3-fold and 4-fold enrichment of MASLD and MASH in individuals with isolated hypertriglyceridemia (p=1.23E-41 and p=1.29E-10, respectively), whereas individuals with isolated hypercholesterolemia had a marginal higher rate of MASLD and no difference in MASH rate compared to control group (p=0.019 and p=0.97, respectively). Among machine learning methods, feed-forward neural network had the best cross-validation MSE on the validation set. Circulating triglycerides, after body mass index (BMI), were the second strongest independent predictor of liver proton density fat fraction (PDFF) with the largest absolute mean Shapley additive explanation (SHAP) value. CONCLUSION: Isolated hypertriglyceridemia is the second strongest, after obesity, independent predictor of MASLD/MASH. Individuals with hypertriglyceridemia, but not with hypercholesterolemia, should be screened for liver disease.
ABSTRACT
The rising prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) poses a significant global health challenge, affecting over 30% of adults worldwide. MASLD is linked to increased mortality rates and substantial healthcare costs, primarily driven by its progression to metabolic dysfunction-associated steatohepatitis (MASH), which can lead to severe liver complications including cirrhosis and hepatocellular carcinoma. Despite its growing burden, effective pharmacotherapy for MASLD/MASH has been lacking until the recent conditional approval of resmetirom by the FDA. Resmetirom, a liver-targeted thyroid hormone receptor-ß selective drug, has shown promise in clinical trials for treating non-cirrhotic MASH with moderate to advanced fibrosis. It has demonstrated efficacy in reducing hepatic fat content, improving liver histology (both MASH resolution and fibrosis improvement), and ameliorating biomarkers of liver damage without significant effects on body weight or glucose metabolism. Notably, resmetirom also exhibits favourable effects on circulating lipids, potentially reducing cardiovascular risk in MASLD/MASH patients. The safety profile of resmetirom appears acceptable, with gastrointestinal adverse events being the most common, though generally mild or moderate. However, long-term surveillance is warranted to monitor for potential risks related to thyroid, gonadal, or bone diseases. Clinical implementation of resmetirom faces challenges in patient selection and monitoring treatment response, and will heavily rely on non-invasive tests for liver fibrosis assessment. Nonetheless, resmetirom represents a landmark breakthrough in MASLD/MASH treatment, paving the way for future therapeutic strategies aiming to mitigate the multifaceted risks associated with this complex metabolic liver disease.
Subject(s)
Fatty Liver , Humans , Fatty Liver/drug therapy , Thyroid Hormone Receptors beta/metabolism , Liver Cirrhosis/drug therapy , Liver/pathology , Liver/drug effects , Liver/metabolism , Pyridazines , Uracil/analogs & derivativesABSTRACT
Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common liver disease worldwide. The risk of developing MAFLD varies among individuals, due to a combination of environmental inherited and acquired genetic factors. Genome-wide association and next-generation sequencing studies are leading to the discovery of the common and rare genetic determinants of MAFLD. Thanks to the great advances in genomic technologies and bioinformatics analysis, genetic and epigenetic factors involved in the disease can be used to develop genetic risk scores specific for liver-related complications, which can improve risk stratification. Genetic and epigenetic factors lead to the identification of specific sub-phenotypes of MAFLD, and predict the individual response to a pharmacological therapy. Moreover, the variant transcripts and protein themselves represent new therapeutic targets. This review will discuss the current status of research into genetic as well as epigenetic modifiers of MAFLD development and progression.
ABSTRACT
Steatotic liver disease (SLD) refers to a spectrum of diseases caused by hepatic lipid accumulation. SLD has emerged as the leading cause of chronic liver disease worldwide. Despite this burden and many years, understanding the pathophysiology of this disease is challenging due to the inaccessibility to human liver specimens. Therefore, cell-based in vitro systems are widely used as models to investigate the pathophysiology of SLD. Culturing hepatic cells in monolayers causes the loss of their hepatocyte-specific phenotype and, consequently, tissue-specific function and architecture. Hence, three-dimensional (3D) culture models allow cells to mimic the in vivo microenvironment and spatial organization of the liver unit. The utilization of 3D in vitro models minimizes the drawbacks of two-dimensional (2D) cultures and aligns with the 3Rs principles to alleviate the number of in vivo experiments. This article provides an overview of liver 3D models highlighting advantages and limitations, and culminates by discussing their applications in pharmaceutical and biomedical research.
Subject(s)
Fatty Liver , Hepatocytes , Liver , Humans , Animals , Hepatocytes/metabolism , Hepatocytes/pathology , Liver/pathology , Liver/metabolism , Fatty Liver/pathology , Fatty Liver/physiopathology , Fatty Liver/metabolism , Cell Culture Techniques, Three Dimensional/methods , Phenotype , Cellular MicroenvironmentABSTRACT
BACKGROUND AND AIMS: The European Association for the Study of the Liver introduced a clinical pathway (EASL CP) for screening significant/advanced fibrosis in people at risk of steatotic liver disease (SLD). We assessed the performance of the first-step FIB4 EASL CP in the general population across different SLD risk groups (MASLD, Met-ALD and ALD) and various age classes. METHODS: We analysed a total of 3372 individuals at risk of SLD from the 2017-2018 National Health and Nutrition Examination Survey (NHANES17-18), projected to 152.3 million U.S. adults, 300,329 from the UK Biobank (UKBB) and 57,644 from the Biobank Japan (BBJ). We assessed liver stiffness measurement (LSM) ≥8 kPa and liver-related events occurring within 3 and 10 years (3/10 year-LREs) as outcomes. We defined MASLD, MetALD, and ALD according to recent international recommendations. RESULTS: FIB4 sensitivity for LSM ≥ 8 kPa was low (27.7%), but it ranged approximately 80%-90% for 3-year LREs. Using FIB4, 22%-57% of subjects across the three cohorts were identified as candidates for vibration-controlled transient elastography (VCTE), which was mostly avoidable (positive predictive value of FIB4 ≥ 1.3 for LSM ≥ 8 kPa ranging 9.5%-13% across different SLD categories). Sensitivity for LSM ≥ 8 kPa and LREs increased with increasing alcohol intake (ALD>MetALD>MASLD) and age classes. For individuals aged ≥65 years, using the recommended age-adjusted FIB4 cut-off (≥2) substantially reduced sensitivity for LSM ≥ 8 kPa and LREs. CONCLUSIONS: The first-step FIB4 EASL CP is poorly accurate and feasible for individuals at risk of SLD in the general population. It is crucial to enhance the screening strategy with a first-step approach able to reduce unnecessary VCTEs and optimise their yield.
Subject(s)
Fatty Liver , Mass Screening , Adult , Aged , Female , Humans , Male , Middle Aged , Elasticity Imaging Techniques , Fatty Liver/diagnostic imaging , Japan , Liver Cirrhosis , Mass Screening/methods , Non-alcoholic Fatty Liver Disease , Nutrition Surveys , Risk Assessment/methods , Risk Factors , Sensitivity and Specificity , United StatesABSTRACT
BACKGROUND: ANGPTL3 (angiopoietin-like protein 3) is a circulating protein with a key role in maintaining lipoprotein homeostasis. A monoclonal antibody against ANGPTL3 is an approved and well-tolerated treatment to reduce lipoproteins in familial hypercholesterolemia homozygotes. However, the reduction of hepatic ANGPTL3 synthesis using an antisense oligonucleotide unexpectedly resulted in a dose-dependent increase in liver lipid content and circulating transaminases, resulting in the termination of the clinical trial. Meanwhile, the use of silencing RNAs remains an area of active investigation. Our study sought to investigate whether intracellular downregulation of ANGPTL3 may lead to a primary increase in neutral lipids within the hepatocyte. METHODS: We downregulated ANGPTL3 by silencing RNA in primary human hepatocytes 3-dimensional spheroids, HepG2/LX-2 3-dimensional spheroids, and in HepG2, Hep3B2, and Huh7 cultured in 2 dimensions. RESULTS: ANGPTL3 downregulation increased neutral lipids in all models investigated. Interestingly, ANGPTL3 induced lower intracellular deiodinase type 1 protein levels resulting in a reduction in beta-oxidation and causing an increase in triglycerides stored in lipid droplets. CONCLUSIONS: In conclusion, intracellular ANGPTL3 downregulation by silencing RNA led to an increase in triglycerides content due to a reduction in energy substrate utilization resembling a primary intracellular hepatocyte hypothyroidism.
Subject(s)
Angiopoietin-Like Protein 3 , Angiopoietin-like Proteins , Down-Regulation , Energy Metabolism , Hepatocytes , RNA Interference , Triglycerides , Humans , Angiopoietin-Like Protein 3/genetics , Angiopoietin-Like Protein 3/metabolism , Angiopoietin-like Proteins/metabolism , Angiopoietin-like Proteins/genetics , Angiopoietins/metabolism , Angiopoietins/genetics , Energy Metabolism/genetics , Hep G2 Cells , Hepatocytes/metabolism , Lipid Metabolism , Transfection , Triglycerides/metabolismABSTRACT
Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses an excess of triglycerides in the liver, which can lead to cirrhosis and liver cancer. While there is solid epidemiological evidence of MASLD coexisting with cardiometabolic disease, several leading genetic risk factors for MASLD do not increase the risk of cardiovascular disease, suggesting no causal relationship between MASLD and cardiometabolic derangement. In this work, we leveraged measurements of visceral adiposity and identified 27 novel genetic loci associated with MASLD. Among these loci, we replicated 6 in several independent cohorts. Next, we generated two partitioned polygenic risk scores (PRS) based on the mechanism of genetic association with MASLD encompassing intra-hepatic lipoprotein retention. The two PRS suggest the presence of at least two distinct types of MASLD, one confined to the liver resulting in a more aggressive liver disease and one that is systemic and results in a higher risk of cardiometabolic disease.
ABSTRACT
OBJECTIVE: Metabolic dysfunction-associated steatotic liver disease (MASLD) is a global health concern with no effective and specific drug treatment available. The rs2642438 minor allele in mitochondrial amidoxime-reducing component 1 (MARC1) results in an aminoacidic substitution (p.Ala165Thr) and associates with protection against MASLD. However, the mechanisms behind this protective effect are unknown. In this study, we examined the consequences of this aminoacidic substitution on protein stability and subcellular localization. METHODS: We overexpressed the human MARC1 A165 (wild-type) or 165T (mutant) in vivo in mice and in vitro in human hepatoma cells (HepG2 and HuH-7), generated several mutants at position 165 by in situ mutagenesis and then examined protein levels. We also generated HepG2 cells stably overexpressing MARC1 A165 or 165T to test the effect of this substitution on MARC1 subcellular localization. RESULTS: MARC1 165T overexpression resulted in lower protein levels than A165 both in vivo and in vitro. Similarly, any mutant at position 165 showed lower protein levels compared to the wild-type protein. We showed that the 165T mutant protein is polyubiquitinated and its degradation is accelerated through lysine-48 ubiquitin-mediated proteasomal degradation. We also showed that the 165T substitution does not affect the MARC1 subcellular localization. CONCLUSIONS: This study shows that alanine at position 165 in MARC1 is crucial for protein stability, and the threonine substitution at this position leads to a hypomorphic protein variant due to lower protein levels. Our result supports the notion that lowering hepatic MARC1 protein level may be a successful therapeutic strategy for treating MASLD.
Subject(s)
Fatty Liver , Mitochondrial Proteins , Oxidoreductases , Proteasome Endopeptidase Complex , Animals , Humans , Mice , Fatty Liver/metabolism , Proteasome Endopeptidase Complex/metabolism , Proteolysis , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Oxidoreductases/genetics , Oxidoreductases/metabolismABSTRACT
BACKGROUND & AIMS: The PNPLA3 rs738409 C>G (encoding for I148M) variant is a risk locus for the fibrogenic progression of chronic liver diseases, a process driven by hepatic stellate cells (HSCs). We investigated how the PNPLA3 I148M variant affects HSC biology using transcriptomic data and validated findings in 3D-culture models. METHODS: RNA sequencing was performed on 2D-cultured primary human HSCs and liver biopsies of individuals with obesity, genotyped for the PNPLA3 I148M variant. Data were validated in wild-type (WT) or PNPLA3 I148M variant-carrying HSCs cultured on 3D extracellular matrix (ECM) scaffolds from human healthy and cirrhotic livers, with/without TGFB1 or cytosporone B (Csn-B) treatment. RESULTS: Transcriptomic analyses of liver biopsies and HSCs highlighted shared PNPLA3 I148M-driven dysregulated pathways related to mitochondrial function, antioxidant response, ECM remodelling and TGFB1 signalling. Analogous pathways were dysregulated in WT/PNPLA3-I148M HSCs cultured in 3D liver scaffolds. Mitochondrial dysfunction in PNPLA3-I148M cells was linked to respiratory chain complex IV insufficiency. Antioxidant capacity was lower in PNPLA3-I148M HSCs, while reactive oxygen species secretion was increased in PNPLA3-I148M HSCs and higher in bioengineered cirrhotic vs. healthy scaffolds. TGFB1 signalling followed the same trend. In PNPLA3-I148M cells, expression and activation of the endogenous TGFB1 inhibitor NR4A1 were decreased: treatment with the Csn-B agonist increased total NR4A1 in HSCs cultured in healthy but not in cirrhotic 3D scaffolds. NR4A1 regulation by TGFB1/Csn-B was linked to Akt signalling in PNPLA3-WT HSCs and to Erk signalling in PNPLA3-I148M HSCs. CONCLUSION: HSCs carrying the PNPLA3 I148M variant have impaired mitochondrial function, antioxidant responses, and increased TGFB1 signalling, which dampens antifibrotic NR4A1 activity. These features are exacerbated by cirrhotic ECM, highlighting the dual impact of the PNPLA3 I148M variant and the fibrotic microenvironment in progressive chronic liver diseases. IMPACT AND IMPLICATIONS: Hepatic stellate cells (HSCs) play a key role in the fibrogenic process associated with chronic liver disease. The PNPLA3 genetic mutation has been linked with increased risk of fibrogenesis, but its role in HSCs requires further investigation. Here, by using comparative transcriptomics and a novel 3D in vitro model, we demonstrate the impact of the PNPLA3 genetic mutation on primary human HSCs' behaviour, and we show that it affects the cell's mitochondrial function and antioxidant response, as well as the antifibrotic gene NR4A1. Our publicly available transcriptomic data, 3D platform and our findings on NR4A1 could facilitate the discovery of targets to develop more effective treatments for chronic liver diseases.
Subject(s)
Extracellular Matrix , Hepatic Stellate Cells , Lipase , Liver Cirrhosis , Membrane Proteins , Transforming Growth Factor beta1 , Humans , Hepatic Stellate Cells/metabolism , Hepatic Stellate Cells/pathology , Membrane Proteins/genetics , Membrane Proteins/metabolism , Extracellular Matrix/metabolism , Extracellular Matrix/genetics , Lipase/genetics , Lipase/metabolism , Liver Cirrhosis/genetics , Liver Cirrhosis/pathology , Liver Cirrhosis/metabolism , Transforming Growth Factor beta1/metabolism , Transforming Growth Factor beta1/genetics , Cells, Cultured , Liver/pathology , Liver/metabolism , Signal Transduction/genetics , Obesity/genetics , Obesity/metabolism , Male , Acyltransferases , Phospholipases A2, Calcium-IndependentABSTRACT
BACKGROUND & AIMS: Previous studies have suggested an increased risk of major adverse liver outcomes (MALO) in relatives of patients with metabolic dysfunction-associated steatotic liver disease (MASLD). However, granular and longitudinal evidence is lacking on the future risk of MALO among family members of individuals with MASLD. METHODS: We identified 3526 first-degree relatives (FDRs) and 11 079 general population comparators to 1328 patients with MASLD diagnosed between 1974 and 2021, with detailed clinical data, including liver histology in 71% of patients. MALO was defined through diagnostic coding for cirrhosis or its complications. Cox regression models were used to estimate adjusted hazard ratios (aHRs) for MALO among FDRs compared to general population comparators. Cumulative incidence accounting for competing risks was calculated. RESULTS: During a median follow-up of 13.4 years, there were 65 (2%, 1.12/1000 person-years) and 225 (2%, 1.26/1000 person-years) MALO events in FDRs and general population comparators respectively. After adjusting for demographic factors and comorbidities, FDRs were at no increased risk of MALO (aHR = 0.99, 95% CI: 0.74-1.33). Increased relative rates of MALOs were, however, observed in some subgroups, including parents, although absolute risk estimates were low and comparable to the general population. CONCLUSIONS: FDRs of patients with MASLD did not have a higher rate of incident MALO than the general population. Since the absolute risk of MALO in relatives of patients with MASLD was low, these results do not support systematic screening of MASLD-related fibrosis in relatives of patients with MASLD.
Subject(s)
Fatty Liver , Metabolic Diseases , Humans , Liver Cirrhosis , ParentsABSTRACT
Steatotic liver disease (SLD) prevails as the most common chronic liver disease yet lack approved treatments due to incomplete understanding of pathogenesis. Recently, elevated hepatic and circulating interleukin 32 (IL-32) levels were found in individuals with severe SLD. However, the mechanistic link between IL-32 and intracellular triglyceride metabolism remains to be elucidated. We demonstrate in vitro that incubation with IL-32ß protein leads to an increase in intracellular triglyceride synthesis, while downregulation of IL32 by small interfering RNA leads to lower triglyceride synthesis and secretion in organoids from human primary hepatocytes. This reduction requires the upregulation of Phospholipase A2 group IIA (PLA2G2A). Furthermore, downregulation of IL32 results in lower intracellular type I collagen levels in di-lineage human primary hepatic organoids. Finally, we identify a genetic variant of IL32 (rs76580947) associated with lower circulating IL-32 and protection against SLD measured by non-invasive tests. These data suggest that IL32 downregulation may be beneficial against SLD.
Subject(s)
Fatty Liver , Liver Diseases , Humans , Collagen Type I/genetics , Collagen Type I/metabolism , Triglycerides/metabolism , Down-Regulation/genetics , Interleukins/genetics , OrganoidsABSTRACT
BACKGROUND & AIMS: The value of non-invasive tests for monitoring the resolution of significant liver fibrosis after treatment is poorly investigated. We compared the performances of six non-invasive tests to predict the resolution of significant fibrosis after bariatric surgery. METHODS: Participants were individuals with obesity submitted to needle liver biopsy at the time of bariatric surgery, and 12 and/or 60 months after surgery. We calculated the fibrosis-4 index (FIB-4), NAFLD fibrosis score (NFS), AST to platelet ratio index (APRI), Hepatic fibrosis score (HFS), Fibrotic NASH index (FNI), and Liver risk score (LRS) at each time point, and compared their performances for predicting significant fibrosis (F ≥ 2) and its resolution following surgery. RESULTS: At baseline, 2436 patients had liver biopsy, including 261 (10.7 %) with significant fibrosis. Overall, 672 patients had pre- and post-operative biopsies (564 at M12 and 328 at M60). The fibrosis stage decreased at M12 and M60 (p < 0.001 vs M0). Resolution of significant fibrosis occurred in 58/121 (47.9 %) at M12 and 32/50 (64 %) at M60. The mean value of all tests decreased after surgery, except for FIB-4. Performances for predicting fibrosis resolution was higher at M60 than at M12 for all tests, and maximal at M60 for FNI and LRS: area under the curve 0.843 (95%CI 0.71-0.95) and 0.92 (95%CI 0.84-1.00); positive likelihood ratio 3.75 (95 % CI 1.33-10.59) and 4.58 (95 % CI 1.65-12.70), respectively. CONCLUSIONS: Results showed the value and limits of non-invasive tests for monitoring the evolution of liver fibrosis after an intervention. Following bariatric surgery, the best performances to predict the resolution of significant fibrosis were observed at M60 with tests combining liver and metabolic traits, namely FNI and LRS.
Subject(s)
Bariatric Surgery , Non-alcoholic Fatty Liver Disease , Humans , Liver Cirrhosis/diagnosis , Liver Cirrhosis/surgery , Liver Cirrhosis/pathology , Non-alcoholic Fatty Liver Disease/diagnosis , Non-alcoholic Fatty Liver Disease/pathology , FibrosisABSTRACT
BACKGROUND & AIMS: Hepatic fat content can be non-invasively estimated by controlled attenuation parameter (CAP) during transient elastography. The aim of this study was to examine the determinants and predictors of CAP values in individuals with metabolic dysfunction. METHODS: We enrolled 1230 consecutive apparently healthy individuals (Liver-Bible-2022 cohort) with ≥3 metabolic dysfunction features. CAP was measured by Fibroscan. CAP determinants and predictors were identified using backward stepwise analysis and introduced in generalized linear models. RESULTS: Participants were predominantly males (82.9%), mean age was 53.8 ± 6.4 years, 600 (48.8%) had steatosis (CAP ≥ 275 dB/m), and 27 had liver stiffness measurement (LSM) ≥ 8 kPa. CAP values correlated with LSM (p < 10-22). In multivariable analysis, fasting insulin and abdominal circumference (AC) were the main determinants of CAP (p < 10-6), together with body mass index (BMI; p < 10-4), age, diabetes, triglycerides, ferritin, and lower HDL and thyroid stimulating hormone (TSH; p < 0.05 for all). In a subset of 592 participants with thyroid hormone measurement, we found an association between higher free triiodothyronine levels, correlating with lower TSH, and CAP values, independent of TSH and of levothyroxine treatment (p = 0.0025). A clinical CAP score based on age, BMI, AC, HbA1c, ALT, and HDL predicted CAP ≥ 275 dB/m with moderate accuracy (AUROC = 0.73), which was better than that of the Fatty Liver Index and of ALT (AUROC = 0.70/0.61, respectively) and validated it in multiple cohorts. CONCLUSION: Abdominal adiposity and insulin resistance severity were the main determinants of CAP in individuals with metabolic dysfunction and may improve steatotic liver disease risk stratification. CAP values were modulated by the hypophysis-thyroid axis.
Subject(s)
Elasticity Imaging Techniques , Fatty Liver , Male , Humans , Middle Aged , Female , Body Mass Index , ThyrotropinABSTRACT
OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD), the primary hepatic consequence of obesity, is affecting about 25% of the global adult population. The aim of this study was to examine the in vivo role of STE20-type protein kinase TAOK3, which has been previously reported to regulate hepatocellular lipotoxicity in vitro, in the development of NAFLD and systemic insulin resistance in the context of obesity. METHODS: Taok3 knockout mice and wild-type littermates were challenged with a high-fat diet. Various in vivo tests were performed to characterize the whole-body metabolism. NAFLD progression in the liver, and lipotoxic damage in adipose tissue, kidney, and skeletal muscle were compared between the genotypes by histological assessment, immunofluorescence microscopy, protein and gene expression profiling, and biochemical assays. Intracellular lipid accumulation and oxidative/ER stress were analyzed in cultured human and mouse hepatocytes where TAOK3 was knocked down by small interfering RNA. The expression of TAOK3-related STE20-type kinases was quantified in different organs from high-fat diet-fed Taok3-/- and wild-type mice. RESULTS: TAOK3 deficiency had no impact on body weight or composition, food consumption, locomotor activity, or systemic glucose or insulin homeostasis in obese mice. Consistently, Taok3-/- mice and wild-type littermates developed a similar degree of high-fat diet-induced liver steatosis, inflammation, and fibrosis, and we detected no difference in lipotoxic damage of adipose tissue, kidney, or skeletal muscle when comparing the two genotypes. In contrast, the silencing of TAOK3 in vitro markedly suppressed ectopic lipid accumulation and metabolic stress in mouse and human hepatocytes. Interestingly, the hepatic mRNA abundance of several TAOK3-related kinases, which have been previously implicated to increase the risk of NAFLD susceptibility, was significantly elevated in Taok3-/- vs. wild-type mice. CONCLUSIONS: In contrast to the in vitro observations, genetic deficiency of TAOK3 in mice failed to mitigate the detrimental metabolic consequences of chronic exposure to dietary lipids, which may be partly attributable to the activation of liver-specific compensation response for the genetic loss of TAOK3 by related STE20-type kinases.
Subject(s)
Non-alcoholic Fatty Liver Disease , Adult , Animals , Humans , Mice , Diet, High-Fat/adverse effects , Lipids , Liver/metabolism , Mice, Inbred C57BL , Mice, Knockout , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/metabolism , Obesity/etiology , Obesity/metabolismABSTRACT
BACKGROUND AND AIMS: The early diagnosis of familial hypercholesterolaemia is associated with a significant reduction in cardiovascular disease (CVD) risk. While the recent use of statistical and machine learning algorithms has shown promising results in comparison with traditional clinical criteria, when applied to screening of potential FH cases in large cohorts, most studies in this field are developed using a single cohort of patients, which may hamper the application of such algorithms to other populations. In the current study, a logistic regression (LR) based algorithm was developed combining observations from three different national FH cohorts, from Portugal, Brazil and Sweden. Independent samples from these cohorts were then used to test the model, as well as an external dataset from Italy. METHODS: The area under the receiver operating characteristics (AUROC) and precision-recall (AUPRC) curves was used to assess the discriminatory ability among the different samples. Comparisons between the LR model and Dutch Lipid Clinic Network (DLCN) clinical criteria were performed by means of McNemar tests, and by the calculation of several operating characteristics. RESULTS: AUROC and AUPRC values were generally higher for all testing sets when compared to the training set. Compared with DLCN criteria, a significantly higher number of correctly classified observations were identified for the Brazilian (p < 0.01), Swedish (p < 0.01), and Italian testing sets (p < 0.01). Higher accuracy (Acc), G mean and F1 score values were also observed for all testing sets. CONCLUSIONS: Compared to DLCN criteria, the LR model revealed improved ability to correctly classify observations, and was able to retain a similar number of FH cases, with less false positive retention. Generalization of the LR model was very good across all testing samples, suggesting it can be an effective screening tool if applied to different populations.