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Background and Aims: Gallstone disease (GSD) associates with significant morbidity and mortality. Decreased secretion of bile acids has been suggested as a driving factor for GSD. Recently, we linked the protein phosphatase 1 regulatory subunit 3 beta (PPP1R3B) rs4240624 genotype to decreased bile acid levels in bile. In this study, we investigated whether these individuals had an increased risk for GSD as well as the differences in the lipid composition of the gallbladder bile of these individuals compared to controls and patients with GSD. Methods: Bile acids, cholesterol, and phospholipid levels in gallbladder bile samples were enzymatically measured in 46 patients (34 female, age 45.7 ± 9.8 years, BMI 41.3 ± 4.4 kg/m2) who underwent elective laparoscopic Roux-en-Y gastric bypass. The lipidome of gallbladder bile was analyzed using high-performance liquid chromatography-mass spectrometry. Gallstone status was evaluated using abdominal ultrasonography before the surgery. Results: The G allele of PPP1R3B rs4240624 was significantly associated with GSD in patients with obesity. We validated this association in the UK Biobank. Bile lipidomics demonstrated that 13 of the 17 minor lipid classes measured were higher in individuals with the G allele. The concentrations of bile acids, cholesterol, and phospholipids, as well as the cholesterol saturation index, were lower in patients with GSD than in those without gallstones. GSD had an effect similar to that of PPP1R3B genotype on minor lipids. Conclusion: The PPP1R3B rs4240624 genotype is associated with gallstones and with changes in gallbladder bile similar to those observed in patients with gallstones, suggesting that the PPP1R3B genotype contributes to the risk of gallstones by altering the bile lipidome.
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BACKGROUND: Abdominal obesity increases the risk for non-alcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: To elucidate the directional cell-type level biological mechanisms underlying the association between abdominal obesity and MASLD, we integrated adipose and liver single nucleus RNA-sequencing and bulk cis-expression quantitative trait locus (eQTL) data with the UK Biobank genome-wide association study (GWAS) data using colocalization. Then we used colocalized cis-eQTL variants as instrumental variables in Mendelian randomization (MR) analyses, followed by functional validation experiments on the target genes of the cis-eQTL variants. FINDINGS: We identified 17 colocalized abdominal obesity GWAS variants, regulating 17 adipose cell-type marker genes. Incorporating these 17 variants into MR discovers a putative tissue-of-origin, cell-type-aware causal effect of abdominal obesity on MASLD consistently with multiple MR methods without significant evidence for pleiotropy or heterogeneity. Single cell data confirm the adipocyte-enriched mean expression of the 17 genes. Our cellular experiments across human adipogenesis identify risk variant -specific epigenetic and transcriptional mechanisms. Knocking down two of the 17 genes, PPP2R5A and SH3PXD2B, shows a marked decrease in adipocyte lipidation and significantly alters adipocyte function and adipogenesis regulator genes, including DGAT2, LPL, ADIPOQ, PPARG, and SREBF1. Furthermore, the 17 genes capture a characteristic MASLD expression signature in subcutaneous adipose tissue. INTERPRETATION: Overall, we discover a significant cell-type level effect of abdominal obesity on MASLD and trace its biological effect to adipogenesis. FUNDING: NIH grants R01HG010505, R01DK132775, and R01HL170604; the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant No. 802825), Academy of Finland (Grants Nos. 333021), the Finnish Foundation for Cardiovascular Research the Sigrid Jusélius Foundation and the Jane and Aatos Erkko Foundation; American Association for the Study of Liver Diseases (AASLD) Advanced Transplant Hepatology award and NIH/NIDDK (P30DK41301) Pilot and Feasibility award; NIH/NIEHS F32 award (F32ES034668); Finnish Diabetes Research Foundation, Kuopio University Hospital Project grant (EVO/VTR grants 2005-2021), the Academy of Finland grant (Contract no. 138006); Academy of Finland (Grant Nos 335443, 314383, 272376 and 266286), Sigrid Jusélius Foundation, Finnish Medical Foundation, Finnish Diabetes Research Foundation, Novo Nordisk Foundation (#NNF20OC0060547, NNF17OC0027232, NNF10OC1013354) and Government Research Funds to Helsinki University Hospital; Orion Research Foundation, Maud Kuistila Foundation, Finish Medical Foundation, and University of Helsinki.
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Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Obesidad Abdominal , Sitios de Carácter Cuantitativo , Humanos , Obesidad Abdominal/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ARN , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/genética , Adipogénesis/genética , Análisis de la Célula Individual , Regulación de la Expresión GénicaRESUMEN
BACKGROUND: Obesity is a worldwide epidemic characterized by adipose tissue (AT) inflammation. AT is also a source of extracellular vesicles (EVs) that have recently been implicated in disorders related to metabolic syndrome. However, our understanding of mechanistic aspect of obesity's impact on EV secretion from human AT remains limited. METHODS: We investigated EVs from human Simpson Golabi Behmel Syndrome (SGBS) adipocytes, and from AT as well as plasma of subjects undergoing bariatric surgery. SGBS cells were treated with TNFα, palmitic acid, and eicosapentaenoic acid. Various analyses, including nanoparticle tracking analysis, electron microscopy, high-resolution confocal microscopy, and gas chromatography-mass spectrometry, were utilized to study EVs. Plasma EVs were analyzed with imaging flow cytometry. RESULTS: EVs from mature SGBS cells differed significantly in size and quantity compared to preadipocytes, disagreeing with previous findings in mouse adipocytes and indicating that adipogenesis promotes EV secretion in human adipocytes. Inflammatory stimuli also induced EV secretion, and altered EV fatty acid (FA) profiles more than those of cells, suggesting the role of EVs as rapid responders to metabolic shifts. Visceral AT (VAT) exhibited higher EV secretion compared to subcutaneous AT (SAT), with VAT EV counts positively correlating with plasma triacylglycerol (TAG) levels. Notably, the plasma EVs of subjects with obesity contained a higher number of adiponectin-positive EVs than those of lean subjects, further demonstrating higher AT EV secretion in obesity. Moreover, plasma EV counts of people with obesity positively correlated with body mass index and TNF expression in SAT, connecting increased EV secretion with AT expansion and inflammation. Finally, EVs from SGBS adipocytes and AT contained TAGs, and EV secretion increased despite signs of less active lipolytic pathways, indicating that AT EVs could be involved in the mobilization of excess lipids into circulation. CONCLUSIONS: We are the first to provide detailed FA profiles of human AT EVs. We report that AT EV secretion increases in human obesity, implicating their role in TAG transport and association with adverse metabolic parameters, thereby emphasizing their role in metabolic disorders. These findings promote our understanding of the roles that EVs play in human AT biology and metabolic disorders.
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Adipocitos , Tejido Adiposo , Vesículas Extracelulares , Inflamación , Obesidad , Humanos , Vesículas Extracelulares/metabolismo , Obesidad/metabolismo , Obesidad/patología , Adipocitos/metabolismo , Inflamación/patología , Inflamación/metabolismo , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Metabolismo de los Lípidos , Femenino , Masculino , Adulto , Ácidos Grasos/metabolismoRESUMEN
BACKROUND: Metabolic dysfunction-associated steatotic liver disease (MASLD) can lead to liver fibrosis, cirrhosis, and hepatocellular carcinoma. Still, most patients with MASLD die from cardiovascular diseases indicating metabolic alterations related to both liver and cardiovascular pathology. AIMS AND METHODS: The aim of this study was to assess biologic pathways behind MASLD progression from steatosis to metabolic dysfunction-associated steatohepatitis (MASH) using non-targeted liquid chromatography-mass spectrometry analysis in 106 severely obese individuals (78 women, mean age 47.7 7 ± 9.2 years, body mass index 41.8 ± 4.3 kg/m²) undergoing laparoscopic Roux-en-Y gastric bypass. RESULTS: We identified several metabolites that are associated with MASLD progression. Most importantly, we observed a decrease of lysophosphatidylcholines LPC(18:2), LPC(18:3), and LPC(20:3) and increase of xanthine when comparing those with steatosis to those with MASH. We found that indole propionic acid and threonine were negatively correlated to fibrosis, but not with the metabolic disturbances associated with cardiovascular risk. Xanthine, ketoleucine, and tryptophan were positively correlated to lobular inflammation and ballooning but also with insulin resistance, and dyslipidemia, respectively. The results did not change when taking into account the most important genetic risk factors of MASLD. CONCLUSIONS: Our findings suggest that there are several separate biological pathways, some of them independent of insulin resistance and dyslipidemia, associating with MASLD.
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Alcohol-associated liver disease (ALD), as highlighted in this narrative review, is a major public health concern, increasingly impacting global disease burden and premature mortality. In 2019, ALD accounted for the loss of 11 million life-years worldwide. The rising number of deaths and disability-adjusted life-years attributed to ALD, particularly pronounced in the United States, are alarming. Projections suggest that the economic impact of ALD, as seen in the United States, could potentially double by 2040. ALD is increasingly prevalent among younger adults (20-45 y) and has become the leading cause of liver transplantation in both United States and Europe. During the COVID-19 pandemic, the existing trend was further amplified as high-risk drinking patterns coincided with a rise in hospital admissions for alcohol-associated hepatitis and increased ALD-related mortality. The prevalence of ALD is estimated at 3.5% in the general population, 26.0% among hazardous drinkers, and 55.1% among those with alcohol use disorders. Alarmingly, 5-year mortality rates for patients with ALD exceed 50%, with even higher rates in more advanced disease stages. Methodological challenges, such as underreporting, diagnostic difficulties, and variability in registry data quality, complicate the accurate assessment of the impact of ALD. Additionally, the contribution of alcohol to the progression of other liver diseases is often under acknowledged in health care registries, leading to a significant underestimation of its broader implications for liver health. Addressing the growing ALD concern requires robust public health initiatives, heightened awareness, refined diagnostic techniques, and comprehensive epidemiological studies. These measures are vital to tackle the increasing prevalence of ALD and mitigate its extensive impact on individuals and health care systems.
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BACKGROUND & AIMS: Hyperferritinemia reflects iron accumulation in the body and has been associated with metabolic disturbances and alcohol use, and is also a common finding in individuals diagnosed with liver disease. The major genetic regulator of iron metabolism is the HFE gene. METHODS: The aim of this this study was to investigate the association between serum ferritin and liver fibrosis using the enhanced liver fibrosis (ELF) test, and the association between ferritin and liver-related outcomes in a Finnish population-based cohort of 6194 individuals (45% male, mean [± standard deviation] age, 52.9 ± 14.9 years; body mass index 26.9 ± 4.7 kg/m2). The effects of HFE variants on these associations were also evaluated. RESULTS: Serum ferritin levels were significantly associated with liver fibrosis, as estimated by enhanced liver fibrosis (ELF) test in weighted linear regression analysis. Serum ferritin was significantly associated with both all liver-related outcomes (n = 92) and severe liver-related outcomes (n = 54) in weighted Cox regression analysis (hazard ratio [HR] per 1 SD, 1.11 [95% confidence interval (CI) 1.02-1.21]; p = 0.012 and HR 1.11 [95% CI 1.02-1.21]; p = 0.013, respectively). However, there was association neither between HFE risk variants and ELF test nor between HFE risk variants and liver-related outcomes. CONCLUSION: Serum ferritin levels were associated with liver fibrosis and incident liver disease, independent of HFE genotype in the general population. Furthermore, data demonstrated that metabolic disturbances and alcohol use were major risk factors for hyperferritinemia.
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Ferritinas , Genotipo , Proteína de la Hemocromatosis , Cirrosis Hepática , Humanos , Masculino , Cirrosis Hepática/sangre , Cirrosis Hepática/genética , Persona de Mediana Edad , Ferritinas/sangre , Proteína de la Hemocromatosis/genética , Femenino , Adulto , Finlandia/epidemiología , Anciano , Modelos de Riesgos Proporcionales , Modelos Lineales , Hiperferritinemia/sangre , Hiperferritinemia/genética , Factores de RiesgoRESUMEN
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.
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Hígado Graso , Hepatopatías , Humanos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Triglicéridos/metabolismo , Regulación hacia Abajo/genética , Interleucinas/genética , OrganoidesRESUMEN
BACKGROUND AND AIMS: A need exists for effective and practical tools to identify individuals at increased risk of liver-related outcomes (LROs) within the general population. APPROACH AND RESULTS: We externally validated the chronic liver disease (CLivD) score for LROs in the UK Biobank cohort. We also investigated the sequential combined use of CLivD and fibrosis-4 (FIB-4) scores. Our analysis included 369,832 adults without baseline liver disease and with available data for CLivD and FIB-4 computation. LROs reflecting compensated or decompensated liver cirrhosis or HCC were ascertained through linkages with electronic health care registries. Discriminatory performance and cumulative incidence were evaluated with competing-risk methodologies. Over a 10-year follow-up, time-dependent AUC values for LRO prediction were 0.80 for CLivD lab (including gamma-glutamyltransferase), 0.72 for CLivD non-lab (excluding laboratory values), and 0.75 for FIB-4. CLivD lab demonstrated AUC values exceeding 0.85 for liver-related death and severe alcohol-associated liver outcomes. The predictive performance of FIB-4 increased with rising CLivD scores; 10-year FIB-4 AUC values ranged from 0.60 within the minimal-risk CLivD subgroup to 0.81 within the high-risk CLivD subgroup. Moreover, in the minimal-risk CLivD subgroup, the cumulative incidence of LRO varied from 0.05% to 0.3% across low-to-high FIB-4 strata. In contrast, within the high-risk CLivD subgroup, the corresponding incidence ranged from 1.7% to 21.1% (up to 33% in individuals with FIB-4 >3.25). CONCLUSIONS: The CLivD score is a valid tool for LRO risk assessment and improves the predictive performance of FIB-4. The combined use of CLivD and FIB-4 identified a subgroup where 1 in 3 individuals developed LROs within 10 years.
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Cirrosis Hepática , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Adulto , Medición de Riesgo/métodos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/epidemiología , Reino Unido/epidemiología , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/diagnóstico , Índice de Severidad de la Enfermedad , Valor Predictivo de las Pruebas , Estudios de Cohortes , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/diagnósticoRESUMEN
BACKGROUND: Obesity is associated with liver disease, but the best obesity-related predictor remains undefined. Controversy exists regarding possible synergism between obesity and alcohol use for liver-related outcomes (LRO). We assessed the predictive performance for LROs, and synergism with alcohol use, of abdominal obesity (waist-hip ratio, WHR), and compared it to overall obesity (body mass index, BMI). METHODS: Forty-thousand nine-hundred twenty-two adults attending the Finnish health-examination surveys, FINRISK 1992-2012 and Health 2000 studies, were followed through linkage with electronic healthcare registries for LROs (hospitalizations, cancers, and deaths). Predictive performance of obesity measures (WHR, waist circumference [WC], and BMI) were assessed by Fine-Gray models and time-dependent area-under-the-curve (AUC). RESULTS: There are 355 LROs during a median follow-up of 12.9 years (509047.8 person-years). WHR and WC emerge as more powerful predictors of LROs than BMI. WHR shows significantly better 10-year AUC values for LROs (0.714, 95% CI 0.685-0.743) than WC (0.648, 95% CI 0.617-0.679) or BMI (0.550, 95% CI 0.514-0.585) both overall and separately among men and women. WHR is predictive also in BMI strata. Absolute 10-year risks of LROs are more dependent on WHR than BMI. Moreover, WHR shows a significant supra-additive interaction effect with harmful alcohol use for liver-related outcomes (excess 10-year cumulative incidence of 2.8% from the interaction), which is not seen between BMI and harmful alcohol use. CONCLUSIONS: WHR is a better predictor than BMI or WC for LROs, and WHR better reflects the synergism with harmful alcohol use. WHR should be included in clinical assessment when evaluating obesity-related risks for liver outcomes.
Obesity has been linked to liver disease, but the most accurate measure for predicting obesity-related liver disease outcomes remains uncertain. In this study, we analyzed data from over 40,000 adults to compare the extent to which different measures of obesity can predict liver-related outcomes, such as severe liver disease, liver failure, or death from liver disease. The measures of obesity were the ratio of waist circumference to hip circumference (waist-hip ratio, WHR), waist circumference (WC), and body mass index (BMI). Our findings reveal that WHR and WC are stronger predictors of these outcomes than BMI. In particular, WHR demonstrated superior predictive ability and this predictive ability was influenced by harmful alcohol use. This study suggests that WHR may be a relatively simple but useful measure for clinicians to use when predicting obesity-related risks for liver health.
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IMPORTANCE: Our study is applying a community-based approach to examine the influence of exercise on gut microbiota (GM) and discover GM structures linked with NAFLD improvements during exercise. The majority of microbiome research has focused on finding specific species that may contribute to the development of human diseases. However, we believe that complex diseases, such as NAFLD, would be more efficiently treated using consortia of species, given that bacterial functionality is based not only on its own genetic information but also on the interaction with other microorganisms. Our results revealed that exercise significantly changes the GM interaction and that structural alterations can be linked with improvements in intrahepatic lipid content and metabolic functions. We believe that the identification of these characteristics in the GM enhances the development of exercise treatment for NAFLD and will attract general interest in this field.
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Microbioma Gastrointestinal , Microbiota , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/terapia , Bacterias/genéticaRESUMEN
BACKGROUND AND AIMS: Persistent organic pollutants (POPs) have multiple adverse effects on human health. Recent studies show a possible association with liver disease, but population-based data are scarce. In this population-based study, we studied the associations between POPs and biomarkers of liver disease and incident liver disease. METHODS: This study consisted of 2789 adults that participated in the environmental toxin subset of the Finnish health-examination survey, FINRISK 2007. Toxins were measured from serum samples, and standard liver tests and dynamic aspartate aminotransferase-alanine aminotransferase ratio (dAAR) were measured as biomarkers of liver function. Associations between POPs and the biomarkers were then analysed using linear regression. Associations between POPs and incident liver disease (n = 36) were analysed by Cox regression. RESULTS: Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and several perfluorinated alkyl substances exhibited statistically significant positive associations with several biomarkers of liver injury (betacoefficient per SD 0.04-0.14, p < 0.05). These associations were stronger in subgroups of individuals with obesity or non-alcoholic fatty liver disease. OCPs, PCBs and perfluoro-octanoic acid also had significant positive associations with dAAR, which can be used to predict risk of incident severe liver outcomes (beta coefficient per SD 0.05-0.08, p < 0.05). OCPs and PCBs were also significantly and positively associated with incident liver disease (hazard ratio per SD 1.82 95% CI 1.21-2.73, p < 0.01 and hazard ratio per SD 1.69, 95% CI 1.07-2.68, p < 0.05 respectively). CONCLUSIONS: Several POPs show positive associations with markers of liver injury and incident liver disease, suggesting that environmental toxins are important risk factors for chronic liver disease.
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Contaminantes Ambientales , Hidrocarburos Clorados , Enfermedad del Hígado Graso no Alcohólico , Plaguicidas , Bifenilos Policlorados , Adulto , Humanos , Contaminantes Orgánicos Persistentes , Finlandia/epidemiología , Contaminantes Ambientales/efectos adversos , Plaguicidas/efectos adversos , BiomarcadoresRESUMEN
Brown adipose tissue (BAT) has the capacity to regulate systemic metabolism through the secretion of signaling lipids. N6-methyladenosine (m 6 A) is the most prevalent and abundant post-transcriptional mRNA modification and has been reported to regulate BAT adipogenesis and energy expenditure. In this study, we demonstrate that the absence of m 6 A methyltransferase-like 14 (METTL14), modifies the BAT secretome to initiate inter-organ communication to improve systemic insulin sensitivity. Importantly, these phenotypes are independent of UCP1-mediated energy expenditure and thermogenesis. Using lipidomics, we identified prostaglandin E2 (PGE2) and prostaglandin F2a (PGF2a) as M14 KO -BAT-secreted insulin sensitizers. Notably, circulatory PGE2 and PGF2a levels are inversely correlated with insulin sensitivity in humans. Furthermore, in vivo administration of PGE2 and PGF2a in high-fat diet-induced insulin-resistant obese mice recapitulates the phenotypes of METTL14 deficient animals. PGE2 or PGF2a improves insulin signaling by suppressing the expression of specific AKT phosphatases. Mechanistically, METTL14-mediated m 6 A installation promotes decay of transcripts encoding prostaglandin synthases and their regulators in human and mouse brown adipocytes in a YTHDF2/3-dependent manner. Taken together, these findings reveal a novel biological mechanism through which m 6 A-dependent regulation of BAT secretome regulates systemic insulin sensitivity in mice and humans. Highlights: Mettl14 KO -BAT improves systemic insulin sensitivity via inter-organ communication; PGE2 and PGF2a are BAT-secreted insulin sensitizers and browning inducers;PGE2 and PGF2a sensitize insulin responses through PGE2-EP-pAKT and PGF2a-FP-AKT axis; METTL14-mediated m 6 A installation selectively destabilizes prostaglandin synthases and their regulator transcripts; Targeting METTL14 in BAT has therapeutic potential to enhance systemic insulin sensitivity.
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BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a fast-growing, underdiagnosed, epidemic. We hypothesise that obesity-related inflammation compromises adipose tissue functions, preventing efficient fat storage, and thus driving ectopic fat accumulation into the liver. METHODS: To identify adipose-based mechanisms and potential serum biomarker candidates (SBCs) for NAFLD, we utilise dual-tissue RNA-sequencing (RNA-seq) data in adipose tissue and liver, paired with histology-based NAFLD diagnosis, from the same individuals in a cohort of obese individuals. We first scan for genes that are differentially expressed (DE) for NAFLD in obese individuals' subcutaneous adipose tissue but not in their liver; encode proteins secreted to serum; and show preferential adipose expression. Then the identified genes are filtered to key adipose-origin NAFLD genes by best subset analysis, knockdown experiments during human preadipocyte differentiation, recombinant protein treatment experiments in human liver HepG2 cells, and genetic analysis. FINDINGS: We discover a set of genes, including 10 SBCs, that may modulate NAFLD pathogenesis by impacting adipose tissue function. Based on best subset analysis, we further follow-up on two SBCs CCDC80 and SOD3 by knockdown in human preadipocytes and subsequent differentiation experiments, which show that they modulate crucial adipogenesis genes, LPL, SREBPF1, and LEP. We also show that treatment of the liver HepG2 cells with the CCDC80 and SOD3 recombinant proteins impacts genes related to steatosis and lipid processing, including PPARA, NFE2L2, and RNF128. Finally, utilizing the adipose NAFLD DE gene cis-regulatory variants associated with serum triglycerides (TGs) in extensive genome-wide association studies (GWASs), we demonstrate a unidirectional effect of serum TGs on NAFLD with Mendelian Randomization (MR) analysis. We also demonstrate that a single SNP regulating one of the SBC genes, rs2845885, produces a significant MR result by itself. This supports the conclusion that genetically regulated adipose expression of the NAFLD DE genes may contribute to NAFLD through changes in serum TG levels. INTERPRETATION: Our results from the dual-tissue transcriptomics screening improve the understanding of obesity-related NAFLD by providing a targeted set of 10 adipose tissue-active genes as new serum biomarker candidates for the currently grossly underdiagnosed fatty liver disease. FUNDING: The work was supported by NIH grants R01HG010505 and R01DK132775. The Genotype-Tissue Expression (GTEx) Project was supported by the Common Fund of the Office of the Director of the National Institutes of Health, and by NCI, NHGRI, NHLBI, NIDA, NIMH, and NINDS. The KOBS study (J. P.) was supported by the Finnish Diabetes Research Foundation, Kuopio University Hospital Project grant (EVO/VTR grants 2005-2019), and the Academy of Finland grant (Contract no. 138006). This study was funded by the European Research Council under the European Union's Horizon 2020 research and innovation program (Grant No. 802825 to M. U. K.). K. H. P. was funded by the Academy of Finland (grant numbers 272376, 266286, 314383, and 335443), the Finnish Medical Foundation, Gyllenberg Foundation, Novo Nordisk Foundation (grant numbers NNF10OC1013354, NNF17OC0027232, and NNF20OC0060547), Finnish Diabetes Research Foundation, Finnish Foundation for Cardiovascular Research, University of Helsinki, and Helsinki University Hospital and Government Research Funds. I. S. was funded by the Instrumentarium Science Foundation. Personal grants to U. T. A. were received from the Matti and Vappu Maukonen Foundation, Ella och Georg Ehrnrooths Stiftelse and the Finnish Foundation for Cardiovascular Research.
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Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Estudio de Asociación del Genoma Completo , Obesidad/complicaciones , Obesidad/genética , Obesidad/metabolismo , Hígado/metabolismo , Biomarcadores/metabolismoRESUMEN
Lifestyle modifications, including increased physical activity and exercise, are recommended for non-alcoholic fatty liver disease (NAFLD). Inflamed adipose tissue (AT) contributes to the progression and development of NAFLD and oxylipins such as hydroxyeicosatetraenoic acids (HETE), hydroxydocosahexanenoic acids (HDHA), prostaglandins (PEG2), and isoprostanoids (IsoP), which all may play a role in AT homeostasis and inflammation. To investigate the role of exercise without weight loss on AT and plasma oxylipin concentrations in NAFLD subjects, we conducted a 12-week randomized controlled exercise intervention. Plasma samples from 39 subjects and abdominal subcutaneous AT biopsy samples from 19 subjects were collected both at the beginning and the end of the exercise intervention. In the AT of women, a significant reduction of gene expression of hemoglobin subunits (HBB, HBA1, HBA2) was observed within the intervention group during the 12-week intervention. Their expression levels were negatively associated with VO2max and maxW. In addition, pathways involved in adipocyte morphology alterations significantly increased, whereas pathways in fat metabolism, branched-chain amino acids degradation, and oxidative phosphorylation were suppressed in the intervention group (p < 0.05). Compared to the control group, in the intervention group, the ribosome pathway was activated, but lysosome, oxidative phosphorylation, and pathways of AT modification were suppressed (p < 0.05). Most of the oxylipins (HETE, HDHA, PEG2, and IsoP) in plasma did not change during the intervention compared to the control group. 15-F2t-IsoP significantly increased in the intervention group compared to the control group (p = 0.014). However, this oxylipin could not be detected in all samples. Exercise intervention without weight loss may influence the AT morphology and fat metabolism at the gene expression level in female NAFLD subjects.
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Entrenamiento de Intervalos de Alta Intensidad , Enfermedad del Hígado Graso no Alcohólico , Humanos , Femenino , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/terapia , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Tejido Adiposo/metabolismo , Pérdida de Peso , Expresión Génica , Hígado/metabolismoRESUMEN
BACKGROUND AND AIMS: Programmed cell death 1/programmed cell death-ligand 1 (PD-1/PDL-1) axis has been reported to modulate liver inflammation and progression to hepatocellular carcinoma (HCC) in patients with nonalcoholic fatty liver disease (NAFLD). Here, we examined whether the PDCD1 variation is associated with NAFLD severity in individuals with liver biopsy. METHODS: We examined the impact of PDCD1 gene variants on HCC, as robust severe liver disease phenotype in UK Biobank participants. The strongest genetic association with the rs13023138 G>C variation was subsequently tested for association with liver damage in 2889 individuals who underwent liver biopsy for suspected nonalcoholic steatohepatitis (NASH). Hepatic transcriptome was examined by RNA-Seq in a subset of NAFLD individuals (n = 121). Transcriptomic and deconvolution analyses were performed to identify biological pathways modulated by the risk allele. RESULTS: The rs13023138 C>G showed the most robust association with HCC in UK Biobank (p = 5.28E-4, OR = 1.32, 95% CI [1.1, 1.5]). In the liver biopsy cohort, rs13023138 G allele was independently associated with severe steatosis (OR 1.17, 95% CI 1.02-1.34; p = .01), NASH (OR 1.22, 95% CI 1.09-1.37; p < .001) and advanced fibrosis (OR 1.26, 95% CI 1.06-1.50; p = .007). At deconvolution analysis, rs13023138 G>C allele was linked to higher hepatic representation of M1 macrophages, paralleled by upregulation of pathways related to inflammation and higher expression of CXCR6. CONCLUSIONS: The PDCD1 rs13023138 G allele was associated with HCC development in the general population and with liver disease severity in patients at high risk of NASH.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Hígado/patología , Inflamación/patología , Apoptosis , Cirrosis Hepática/complicacionesRESUMEN
BACKGROUND: When postoperative multi-slice computed tomography (MSCT) imaging of patients with craniosynostosis is used, it is usually performed a few days after surgery in a radiology department. This requires additional anesthesia for the patient. Recently, intraoperative mobile cone-beam CT (CBCT) devices have gained popularity for orthopedic and neurosurgical procedures, which allows postoperative CT imaging in the operating room. OBJECTIVE: This single-center retrospective study compared radiation dose and image quality of postoperative imaging performed using conventional MSCT scanners and O-arm CBCT. MATERIALS AND METHODS: A total of 104 pediatric syndromic and non-syndromic patients who were operated on because of single- or multiple-suture craniosynostosis were included in this study. The mean volumetric CT dose index (CTDIvol) and dose-length product (DLP) values of optimized craniosynostosis CT examinations (58 MSCT and 46 CBCT) were compared. Two surgeons evaluated the subjective image quality. RESULTS: CBCT resulted in significantly lower CTDIvol (up to 14%) and DLP (up to 33%) compared to MSCT. Multi-slice CT image quality was considered superior to CBCT scans. However, all scans were considered to be of sufficient quality for diagnosis. CONCLUSION: The O-arm device allowed for an immediate postoperative CBCT examination in the operating theater using the same anesthesia induction. Radiation exposure was lower in CBCT compared to MSCT scans, thus further encouraging the use of O-arms. Cone-beam CT imaging with an O-arm is a feasible method for postoperative craniosynostosis imaging, yielding less anesthesia to patients, lower health costs and the possibility to immediately evaluate results of the surgical operation.
Asunto(s)
Craneosinostosis , Cirugía Asistida por Computador , Humanos , Niño , Tomografía Computarizada por Rayos X/métodos , Imagenología Tridimensional/métodos , Estudios Retrospectivos , Dosis de Radiación , Fantasmas de Imagen , Tomografía Computarizada de Haz Cónico/métodos , Craneosinostosis/diagnóstico por imagen , Craneosinostosis/cirugía , Tomografía Computarizada Multidetector/métodosRESUMEN
Both genetic and non-genetic factors are important in the pathophysiology of non-alcoholic fatty liver disease (NAFLD). The aim of our study was to identify novel metabolites and pathways associated with NAFLD by including both genetic and non-genetic factors in statistical analyses. We genotyped six genetic variants in the PNPLA3, TM6SF2, MBOAT7, GCKR, PPP1R3B, and HSD17B13 genes reported to be associated with NAFLD. Non-targeted metabolomic profiling was performed from plasma samples. We applied a previously validated fatty liver index to identify participants with NAFLD. First, we associated the six genetic variants with 1098 metabolites in 2 339 men without NAFLD to determine the effects of the genetic variants on metabolites, and then in 2 535 men with NAFLD to determine the joint effects of genetic variants and non-genetic factors on metabolites. We identified several novel metabolites and metabolic pathways, especially for PNPLA3, GCKR, and PPP1R38 variants relevant to the pathophysiology of NAFLD. Importantly, we showed that each genetic variant for NAFLD had a specific metabolite signature. The plasma metabolite signature was unique for each genetic variant, suggesting that several metabolites and different pathways are involved in the risk of NAFLD. The FLI index reliably identifies metabolites for NAFLD in large population-based studies.
RESUMEN
BACKGROUND: Accumulation of saturated fatty acids (SFAs) in the liver is known to induce hepatic steatosis and inflammation causing non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). Although SFAs have been shown to affect the epigenome in whole blood, pancreatic islets, and adipose tissue in humans, and genome-wide DNA methylation studies have linked epigenetic changes to NAFLD and NASH, studies focusing on the association of SFAs and DNA methylation in human liver are missing. We, therefore, investigated whether human liver SFA content associates with DNA methylation and tested if SFA-linked alterations in DNA methylation associate with NAFLD-related clinical phenotypes in obese individuals. RESULTS: We identified DNA methylation (Infinium HumanMethylation450 BeadChip) of 3169 CpGs to be associated with liver total SFA content (q-value < 0.05) measured using proton NMR spectroscopy in participants of the Kuopio Obesity Surgery Study (n = 51; mean ± SD:49.3 ± 8.5 years old; BMI:43.7 ± 6.2 kg/m2). Of these 3169 sites, 797 overlapped with previously published NASH-associated CpGs (NASH-SFA), while 2372 CpGs were exclusively associated with SFA (Only-SFA). The corresponding annotated genes of these only-SFA CpGs were found to be enriched in pathways linked to satiety and hunger. Among the 54 genes mapping to these enriched pathways, DNA methylation of CpGs mapping to PRKCA and TSPO correlated with their own mRNA expression (HumanHT-12 Expression BeadChip). In addition, DNA methylation of another ten of these CpGs correlated with the mRNA expression of their neighboring genes (p value < 0.05). The proportion of CpGs demonstrating a correlation of DNA methylation with plasma glucose was higher in NASH-SFA and only-SFA groups, while the proportion of significant correlations with plasma insulin was higher in only-NASH and NASH-SFA groups as compared to all CpGs on the Illumina 450 K array (Illumina, San Diego, CA, USA). CONCLUSIONS: Our results suggest that one of the mechanisms how SFA could contribute to metabolic dysregulation in NAFLD is at the level of DNA methylation. We further propose that liver SFA-related DNA methylation profile may contribute more to hyperglycemia, while insulin-related methylation profile is more linked to NAFLD or NASH. Further research is needed to elucidate the molecular mechanisms behind these observations.