Browsing by Subject "NAFLD"

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  • Latorre, Jèssica; Ortega, Francisco J.; Liñares-Pose, Laura; Moreno-Navarrete, José M.; Lluch, Aina; Comas, Ferran; Oliveras-Cañellas, Núria; Ricart, Wifredo; Höring, Marcus; Zhou, You; Liebisch, Gerhard; Nidhina Haridas, P.A.; Olkkonen, Vesa M.; López, Miguel; Fernández-Real, José M. (2020)
    Background: While the impact of metformin in hepatocytes leads to fatty acid (FA) oxidation and decreased lipogenesis, hepatic microRNAs (miRNAs) have been associated with fat overload and impaired metabolism, contributing to the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Methods: We investigated the expression of hundreds of miRNAs in primary hepatocytes challenged by compounds modulating steatosis, palmitic acid and compound C (as inducers), and metformin (as an inhibitor). Then, additional hepatocyte and rodent models were evaluated, together with transient mimic miRNAs transfection, lipid droplet staining, thin-layer chromatography, quantitative lipidomes, and mitochondrial activity, while human samples outlined the translational significance of this work. Findings: Our results show that treatments triggering fat accumulation and AMPK disruption may compromise the biosynthesis of hepatic miRNAs, while the knockdown of the miRNA-processing enzyme DICER in human hepatocytes exhibited increased lipid deposition. In this context, the ectopic recovery of miR-30b and miR-30c led to significant changes in genes related to FA metabolism, consistent reduction of ceramides, higher mitochondrial activity, and enabled b-oxidation, redirecting FA metabolism fromenergy storage to expenditure. Interpretation: Current findings unravel the biosynthesis of hepatic miR-30b and miR-30c in tackling inadequate FA accumulation, offering a potential avenue for the treatment of NAFLD. Funding: Instituto de Salud Carlos III (ISCIII), Govern de la Generalitat (PERIS2016), Associacio Catalana de Diabetis (ACD), Sociedad Espanola de Diabetes (SED), Fondo Europeo de Desarrollo Regional (FEDER), Xunta de Galicia, Ministerio de Economia y Competitividad (MINECO), "La Caixa" Foundation, and CIBER de la Fisiopatologia de la Obesidad y Nutricion (CIBEROBN). (c) 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)
  • Pirhonen, Juho; Arola, Johanna; Sädevirta, Sanja; Luukkonen, Panu; Karppinen, Sanna-Mari; Pihlajaniemi, Taina; Isomäki, Antti; Hukkanen, Mika; Yki-Järvinen, Hannele; Ikonen, Elina (Helsingin yliopisto, 2016)
    Maksan rasvoittumisen ajatellaan joskus olevan vain metabolisen oireyhtymän hyvälaatuinen maksamanifestaatio, vaikka se johtaa, erityisesti maksan fibrotisoituessa, kasvaneeseen kardiovaskulaarikuolleisuuteen ja pahimmillaan maksasyöpään. Tästä kansanterveydellisesti merkittävästä roolista huolimatta rasvamaksa on alidiagnosoitu ja sen patogeneettiset mekanismit ovat huonosti ymmärrettyjä, molemmat osin hyvien diagnostisten työkalujen puutteesta johtuen. Päätimme selvittää uusien non-lineaaristen kuvantamismodaliteettien soveltuvuutta rasvamaksan varhaisessa diagnostiikassa. Selvitimme 32 lihavuusleikkauspotilaan maksakudoskoepalojen kudosarkkitehtuurin perinteisin kudosvärjäysmenetelmin ja vertasimme tuloksia samojen potilaiden non-lineaarisesti kuvannettuihin näytteisiin. Kuvansimme minimaalisesti käsitellyistä jääleikkeistä coherent anti-Stokes Raman scattering (CARS) ja second harmonic generation (SHG) signaalit, joita hyödyntäen arvioimme näytteiden rasva- ja kollageenipitoisuuden. Kehitimme myös kuva-analytiikka-algoritmin, joka mahdollistaa kollageenisignaalin automatisoidun ja objektiivisen arvioimisen. Näytteistä mittaamamme SHG- ja CARS-signaalit korreloivat hyvin patologien arvioihin näytteiden fibrotisoitumis- ja rasvoittumisasteista, minkä lisäksi automatisoitu algoritmimme erotteli luotettavasti jopa varhaisen fibroosin normaalista kudoksesta. Myös terveiksi luokiteltujen näytteiden maksakudoksen keskellä esiintyi hienoa fibrillaarista SHG-signaalia. Tunnistamamme SHG-signaali oli spesifiä kolokalisoituen hyvin kollageeni-I- ja III-vasta-ainevärjäyksien kanssa. Tuloksemme osoittavat, että multimodaalisten kuvantamismenetelmien avulla voidaan tunnistaa maksan fibrillaarista kollageenia perinteisiä kudostutkimusmenetelmiä herkemmin. Kehittämämme kuva-analyysi-algoritmi puolestaan arvioi varhaisen fibroosin määrän nopeasti, objektiivisesti ja jatkuvalla skaalalla. Yhdessä nämä löydökset luovat edellytykset tutkia esimerkiksi maksan vähäisen fibroosin kliinistä merkitystä ja paranemistaipumusta isommissa potilasaineistoissa.
  • Harjumäki, Riina; Pridgeon, Chris S.; Ingelman-Sundberg, Magnus (2021)
    CYP2E1 is one of the fifty-seven cytochrome P450 genes in the human genome and is highly conserved. CYP2E1 is a unique P450 enzyme because its heme iron is constitutively in the high spin state, allowing direct reduction of, e.g., dioxygen, causing the formation of a variety of reactive oxygen species and reduction of xenobiotics to toxic products. The CYP2E1 enzyme has been the focus of scientific interest due to (i) its important endogenous function in liver homeostasis, (ii) its ability to activate procarcinogens and to convert certain drugs, e.g., paracetamol and anesthetics, to cytotoxic end products, (iii) its unique ability to effectively reduce dioxygen to radical species causing liver injury, (iv) its capability to reduce compounds, often generating radical intermediates of direct toxic or indirect immunotoxic properties and (v) its contribution to the development of alcoholic liver disease, steatosis and NASH. In this overview, we present the discovery of the enzyme and studies in humans, 3D liver systems and genetically modified mice to disclose its function and clinical relevance. Induction of the CYP2E1 enzyme either by alcohol or high-fat diet leads to increased severity of liver pathology and likelihood to develop ALD and NASH, with subsequent influence on the occurrence of hepatocellular cancer. Thus, fat-dependent induction of the enzyme might provide a link between steatosis and fibrosis in the liver. We conclude that CYP2E1 has many important physiological functions and is a key enzyme for hepatic carcinogenesis, drug toxicity and liver disease.
  • Jamialahmadi, Oveis; Mancina, Rosellina Margherita; Ciociola, Ester; Tavaglione, Federica; Luukkonen, Panu K.; Baselli, Guido; Malvestiti, Francesco; Thuillier, Dorothee; Raverdy, Violeta; Mannisto, Ville; Pipitone, Rosaria Maria; Pennisi, Grazia; Prati, Daniele; Spagnuolo, Rocco; Petta, Salvatore; Pihlajamaki, Jussi; Pattou, Francois; Yki-Järvinen, Hannele; Valenti, Luca; Romeo, Stefano (2021)
    BACKGROUND & AIMS: Fatty liver disease (FLD) is a growing epidemic that is expected to be the leading cause of end-stage liver disease within the next decade. Both environmental and genetic factors contribute to the susceptibility of FLD. Several genetic variants contributing to FLD have been identified in exome-wide association studies. However, there is still a missing hereditability indicating that other genetic variants are yet to be discovered. METHODS: To find genes involved in FLD, we first examined the association of missense and nonsense variants with alanine amino transferase at an exome-wide level in 425,671 participants from the UK Biobank. We then validated genetic variants with liver fat content in 8930 participants in whom liver fat measurement was available, and replicated 2 genetic variants in 3 independent cohorts comprising 2621 individuals with available liver biopsy. RESULTS: We identified 190 genetic variants independently associated with alanine aminotransferase after correcting for multiple testing with Bonferroni method. The majority of these variants were not previously associated with this trait. Among those associated, there was a striking enrichment of genetic variants influencing lipid metabolism. We identified the variants rs2792751 in GPAM/GPAT1, the gene encoding glycerol-3phosphate acyltransferase, mitochondrial, and rs429358 in APOE, the gene encoding apolipoprotein E, as robustly associated with liver fat content and liver disease after adjusting for multiple testing. Both genes affect lipid metabolism in the liver. CONCLUSIONS: We identified 2 novel genetic variants in GPAM and APOE that are robustly associated with steatosis and liver damage. These findings may help to better elucidate the genetic susceptibility to FLD onset and progression.
  • Lahelma, Mari (Helsingfors universitet, 2016)
    Vähäinen fyysinen aktiivisuus lisää ylipainon ja useiden siihen liittyvien sairauksien, kuten tyypin 2 diabeteksen ja sydän- ja verisuonitautien riskiä. Fyysisen aktiivisuuden mittaus mahdollistaa aktiivisuuden ja terveyden välisen yhteyden tutkimisen sekä entistä tehokkaampien liikuntainterventioiden kehittämisen. Tämän tutkielman tavoitteena oli perehtyä liikunnan mittausmenetelmiin ja pystyttää kaksi menetelmää tutkimusryhmän käyttöön. Yleisimpiä fyysisen aktiivisuuden mittausmenetelmiä ovat kyselykaavakkeet, kaksoismerkattu vesi, kiihtyvyysmittari, askelmittari, sykemittari ja gyroskooppi. Näistä kyselykaavake on laajasti kliinisessä käytössä sen käytön helppouden ja edullisuuden ansiosta, ja se soveltuu hyvin käytettäväksi isoissa tutkimusryhmissä. Sen heikkouksia ovat epätarkkuus ja subjektiivisen raportoinnin epävarmuus. Objektiiviset menetelmät, kuten kaksoismerkattu vesi, askel- ja kiihtyvyysmittari sekä gyroskooppi, mahdollistavat tarkemmat ja luotettavammat mittaustulokset, mutta ovat kalliimpia ja tulosten saaminen hitaampaa. Tutkielmassa hyvin validoitu Aktiivisuuskyselylomake (Modifiable Activity Questionnaire) suomennettiin ja sen käyttöä testattiin haastattelemalla se kymmenellä koehenkilöllä. Lisäksi otettiin käyttöön aktiivisuusmittari ActiGraph wGT3X-BT samassa tutkimusryhmässä, ja kokeiltiin sen käyttöä samoilla koehenkilöillä. Pystytettyjä menetelmiä tullaan käyttämään rasvamaksatutkimukseen osallistuvilla potilailla HUS Kliinisen tutkimuksen rasvamaksatutkimusyksikössä.
  • Anstee, Quentin M.; Darlay, Rebecca; Cockell, Simon; Meroni, Marica; Govaere, Olivier; Tiniakos, Dina; Burt, Alastair D.; Bedossa, Pierre; Palmer, Jeremy; Liu, Yang-Lin; Aithal, Guruprasad P.; Allison, Michael; Yki-Järvinen, Hannele; Vacca, Michele; Dufour, Jean-Francois; Invernizzi, Pietro; Prati, Daniele; Ekstedt, Mattias; Kechagias, Stergios; Francque, Sven; Petta, Salvatore; Bugianesi, Elisabetta; Clement, Karine; Ratziu, Vlad; Schattenberg, Jörn M.; Valenti, Luca; Day, Christopher P.; Cordell, Heather J.; Daly, Ann K. (2020)
    Background and Aims Genetic factors associated with non-alcoholic fatty liver disease (NAFLD) remain incompletely understood. To date, most GWAS studies have adopted radiologically assessed hepatic triglyceride content as reference phenotype and so cannot address steatohepatitis or fibrosis. We describe a genome-wide association study (GWAS) encompassing the full spectrum of histologically characterized NAFLD. Methods The GWAS involved 1483 European NAFLD cases and 17781 genetically-matched population controls. A replication cohort of 559 NAFLD cases and 945 controls was genotyped to confirm signals showing genome-wide or close to genome-wide significance. Results Case-control analysis identified signals showing p-values ≤ 5 x 10-8 at four locations (chromosome (chr) 2 GCKR/C2ORF16; chr4 HSD17B13; chr19 TM6SF2; chr22 PNPLA3) together with two other signals with p
  • Laitakari, Anna; Tapio, Joona; Mäkelä, Kari A.; Herzig, Karl-Heinz; Dengler, Franziska; Gylling, Helena; Walkinshaw, Gail; Myllyharju, Johanna; Dimova, Elitsa Y.; Serpi, Raisa; Koivunen, Peppi (2020)
    Non-alcoholic fatty liver disease (NAFLD) parallels the global obesity epidemic with unmet therapeutic needs. We investigated whether inhibition of hypoxia-inducible factor prolyl 4-hydroxylase-2 (HIF-P4H-2), a key cellular oxygen sensor whose inhibition stabilizes HIF, would protect from NAFLD by subjecting HIF-P4H-2-deficient (Hif-p4h-2(gt/gt)) mice to a high-fat, high-fructose (HFHF) or high-fat, methionine-choline-deficient (HF-MCD) diet. On both diets, the Hif-p4h-2(gt/gt) mice gained less weight and had less white adipose tissue (WAT) and its inflammation, lower serum cholesterol levels, and lighter livers with less steatosis and lower serum ALT levels than the wild type (WT). The intake of fructose in majority of the Hif-p4h-2(gt/gt) tissues, including the liver, was 15-35% less than in the WT. We found upregulation of the key fructose transporter and metabolizing enzyme mRNAs, Slc2a2, Khka, and Khkc, and higher ketohexokinase activity in the Hif-p4h-2(gt/gt) small intestine relative to the WT, suggesting enhanced metabolism of fructose in the former. On the HF-MCD diet, the Hif-p4h-2(gt/gt) mice showed more browning of the WAT and increased thermogenesis. A pharmacological pan-HIF-P4H inhibitor protected WT mice on both diets against obesity, metabolic dysfunction, and liver damage. These data suggest that HIF-P4H-2 inhibition could be studied as a novel, comprehensive treatment strategy for NAFLD. Key messages center dot HIF-P4H-2 inhibition enhances intestinal fructose metabolism protecting the liver. center dot HIF-P4H-2 inhibition downregulates hepatic lipogenesis. center dot Induced browning of WAT and increased thermogenesis can also mediate protection. center dot HIF-P4H-2 inhibition offers a novel, comprehensive treatment strategy for NAFLD.
  • Jian, Ching (Helsingfors universitet, 2016)
    Non-alcoholic fatty liver disease (NAFLD) is currently the most common liver disease in the western world. The human intestinal microbiota possesses enormous metabolic and immunomodulatory capabilities, and together with increased intestinal permeability, changes in the microbiota have been linked to the development of NAFLD. However, human studies so far have yielded contradictory findings regarding the compositional microbiota changes and provided little mechanistic understanding due to the predominance of cross-sectional studies. The aim of this study was to study human intestinal microbiota and gut permeability in NAFLD. Real-time PCR was employed to quantify the key intestinal bacterial groups in overweight or obese subjects with (n = 12) and without (n = 19) NAFLD, and in response to hypercaloric overfeeding, where participants were provided with three compositionally distinct diets to temporarily increase liver fat. In addition to the comparative analysis, the microbiota results were correlated to serum markers of intestinal permeability and metabolic endotoxemia, as well as clinical parameters related to NAFLD. The results show that host lipid metabolism and the gut microbiota, specifically Bacteroidetes and Clostridium cluster XIVa, are firmly intercorrelated. Bacteroidetes were found to be less abundant in subjects with NAFLD and correlate negatively with liver fat and serum triglycerides at baseline. Clostridium cluster XIVa, a dominant Firmicute group, was positively associated with serum triglycerides and pro-inflammatory markers but negatively with intestinal permeability. The relative abundance of Bacteroidetes as well as the markers of metabolic endotoxemia changed significantly in response to overfeeding, while no diet-induced systematic effects were found in Clostridium cluster XIVa, total bacteria, Escherichia coli group, Bifidobacterium or gut permeability. Our results based on a targeted microbiota analysis suggest that the role of the intestinal microbiota and gut permeability on triggering metabolic disarrangement and NAFLD in humans is inferior to other stimuli, such as diet.
  • Åberg, Fredrik; Färkkilä, Martti; Männistö, Ville (2020)
    Coexistence of alcohol use and metabolic risk-the 2 commonest population risk factors for nonviral chronic liver disease-is a growing concern. Clinical evidence and mechanistic evidence point to considerable supraadditive interaction effects for the development and progression of chronic liver disease between hazardous alcohol use and metabolic abnormalities including obesity, diabetes, and the metabolic syndrome (MetS). Intermittent binge drinking once monthly or more often seems to be associated with progression of liver disease even when average alcohol intake is within the currently allowed limits for a diagnosis of nonalcoholic fatty liver disease (NAFLD), and supraadditive interaction between binge drinking and the MetS has been reported. There are contradictory findings regarding the association between low alcohol use and liver steatosis, but, clearly, the mechanisms of alcoholic hepatotoxicity extend beyond simple fat accumulation. The presence of liver steatosis seems to amplify alcoholic hepatotoxicity. Recent longitudinal studies of NAFLD subjects report low alcohol use associated with both increased fibrosis progression and an elevated risk for liver cancer and severe liver disease. There is no clear safe limit of alcohol intake in the presence of NAFLD or metabolic risk. The interaction effects between alcohol and metabolic dysfunction merit increased attention in public health policy, individual counseling, and risk stratification. Based on current evidence, a strict dichotomization of liver disease into either pure alcoholic or nonalcoholic may be inappropriate.
  • Mardinoglu, Adil; Bjornson, Elias; Zhang, Cheng; Klevstig, Martina; Söderlund, Sanni; Ståhlman, Marcus; Adiels, Martin; Hakkarainen, Antti; Lundbom, Nina; Kilicarslan, Murat; Hallström, Björn M.; Lundbom, Jesper; Verges, Bruno; Barrett, Peter Hugh R.; Watts, Gerald F.; Serlie, Mireille J.; Nielsen, Jens; Uhlen, Mathias; Smith, Ulf; Marschall, Hanns-Ulrich; Taskinen, Marja-Riitta; Boren, Jan (2017)
    To elucidate the molecular mechanisms underlying non-alcoholic fatty liver disease (NAFLD), we recruited 86 subjects with varying degrees of hepatic steatosis (HS). We obtained experimental data on lipoprotein fluxes and used these individual measurements as personalized constraints of a hepatocyte genome-scale metabolic model to investigate metabolic differences in liver, taking into account its interactions with other tissues. Our systems level analysis predicted an altered demand for NAD(+) and glutathione (GSH) in subjects with high HS. Our analysis and metabolomic measurements showed that plasma levels of glycine, serine, and associated metabolites are negatively correlated with HS, suggesting that these GSH metabolism precursors might be limiting. Quantification of the hepatic expression levels of the associated enzymes further pointed to altered de novo GSH synthesis. To assess the effect of GSH and NAD(+) repletion on the development of NAFLD, we added precursors for GSH and NAD(+) biosynthesis to the Western diet and demonstrated that supplementation prevents HS in mice. In a proof-of-concept human study, we found improved liver function and decreased HS after supplementation with serine (a precursor to glycine) and hereby propose a strategy for NAFLD treatment.
  • Atabaki-Pasdar, Naeimeh; Ohlsson, Mattias; Vinuela, Ana; Frau, Francesca; Pomares-Millan, Hugo; Haid, Mark; Jones, Angus G.; Thomas, E. Louise; Koivula, Robert W.; Kurbasic, Azra; Mutie, Pascal M.; Fitipaldi, Hugo; Fernandez, Juan; Dawed, Adem Y.; Giordano, Giuseppe N.; Forgie, Ian M.; McDonald, Timothy J.; Rutters, Femke; Cederberg, Henna; Chabanova, Elizaveta; Dale, Matilda; Masi, Federico De; Thomas, Cecilia Engel; Allin, Kristine H.; Hansen, Tue H.; Heggie, Alison; Hong, Mun-Gwan; Elders, Petra J. M.; Kennedy, Gwen; Kokkola, Tarja; Pedersen, Helle Krogh; Mahajan, Anubha; McEvoy, Donna; Pattou, Francois; Raverdy, Violeta; Haussler, Ragna S.; Sharma, Sapna; Thomsen, Henrik S.; Vangipurapu, Jagadish; Vestergaard, Henrik; 't Hart, Leen M.; Adamski, Jerzy; Musholt, Petra B.; Brage, Soren; Brunak, Soren; Dermitzakis, Emmanouil; Frost, Gary; Hansen, Torben; Laakso, Markku; Pedersen, Oluf; Ridderstrale, Martin; Ruetten, Hartmut; Hattersley, Andrew T.; Walker, Mark; Beulens, Joline W. J.; Mari, Andrea; Schwenk, Jochen M.; Gupta, Ramneek; McCarthy, Mark I.; Pearson, Ewan R.; Bell, Jimmy D.; Pavo, Imre; Franks, Paul W. (2020)
    Background Non-alcoholic fatty liver disease (NAFLD) is highly prevalent and causes serious health complications in individuals with and without type 2 diabetes (T2D). Early diagnosis of NAFLD is important, as this can help prevent irreversible damage to the liver and, ultimately, hepatocellular carcinomas. We sought to expand etiological understanding and develop a diagnostic tool for NAFLD using machine learning. Methods and findings We utilized the baseline data from IMI DIRECT, a multicenter prospective cohort study of 3,029 European-ancestry adults recently diagnosed with T2D (n= 795) or at high risk of developing the disease (n= 2,234). Multi-omics (genetic, transcriptomic, proteomic, and metabolomic) and clinical (liver enzymes and other serological biomarkers, anthropometry, measures of beta-cell function, insulin sensitivity, and lifestyle) data comprised the key input variables. The models were trained on MRI-image-derived liver fat content (= 5%) available for 1,514 participants. We applied LASSO (least absolute shrinkage and selection operator) to select features from the different layers of omics data and random forest analysis to develop the models. The prediction models included clinical and omics variables separately or in combination. A model including all omics and clinical variables yielded a cross-validated receiver operating characteristic area under the curve (ROCAUC) of 0.84 (95% CI 0.82, 0.86;p = 5%) rather than a continuous one. Conclusions In this study, we developed several models with different combinations of clinical and omics data and identified biological features that appear to be associated with liver fat accumulation. In general, the clinical variables showed better prediction ability than the complex omics variables. However, the combination of omics and clinical variables yielded the highest accuracy. We have incorporated the developed clinical models into a web interface (see:) and made it available to the community.
  • EU-PNAFLD Investigators; GOLD Consortium; Teo, Kevin; Abeysekera, Kushala W. M.; Luukkonen, Panu K.; Yki-Järvinen, Hannele (2021)
    Background & Aims: A common genetic variant near MBOAT7 (rs641738C>T) has been previously associated with hepatic fat and advanced histology in NAFLD; however, these findings have not been consistently replicated in the literature. We aimed to establish whether rs641738C>T is a risk factor across the spectrum of NAFLD and to characterise its role in the regulation of related metabolic phenotypes through a meta-analysis. Methods: We performed a meta-analysis of studies with data on the association between rs641738C>T genotype and liver fat, NAFLD histology, and serum alanine aminotransferase (ALT), lipids or insulin. These included directly genotyped studies and population-level data from genome-wide association studies (GWAS). We performed a random effects meta-analysis using recessive, additive and dominant genetic models. Results: Data from 1,066,175 participants (9,688 with liver biopsies) across 42 studies were included in the meta-analysis. rs641738C>T was associated with higher liver fat on CT/MRI (+0.03 standard deviations [95% CI 0.02-0.05], p(z) = 4.8x10(-5)) and diagnosis of NAFLD (odds ratio [OR] 1.17 [95% CI 1.05-1.3], p(z) = 0.003) in Caucasian adults. The variant was also positively associated with presence of advanced fibrosis (OR 1.22 [95% CI 1.03-1.45], p(z) = 0.021) in Caucasian adults using a recessive model of inheritance (CC + CT vs. TT). Meta-analysis of data from previous GWAS found the variant to be associated with higher ALT (p(z) = 0.002) and lower serum triglycerides (p(z) = 1.5x10(-4)). rs641738C>T was not associated with fasting insulin and no effect was observed in children with NAFLD. Conclusions: Our study validates rs641738C>T near MBOAT7 as a risk factor for the presence and severity of NAFLD in individuals of European descent. Lay summary: Fatty liver disease is a common condition where fat builds up in the liver, which can cause liver inflammation and scarring (including 'cirrhosis'). It is closely linked to obesity and diabetes, but some genes are also thought to be important. We did this study to see whether one specific change ('variant') in one gene ('MBOAT7') was linked to fatty liver disease. We took data from over 40 published studies and found that this variant near MBOAT7 is linked to more severe fatty liver disease. This means that drugs designed to work on MBOAT7 could be useful for treating fatty liver disease. (C) 2020 European Association for the Study of the Liver. Published by Elsevier B.V.
  • Zhang, Cheng; Bjornson, Elias; Arif, Muhammad; Tebani, Abdellah; Lovric, Alen; Benfeitas, Rui; Ozcan, Mehmet; Juszczak, Kajetan; Kim, Woonghee; Kim, Jung Tae; Bidkhori, Gholamreza; Ståhlman, Marcus; Bergh, Per-Olof; Adiels, Martin; Turkez, Hasan; Taskinen, Marja-Riitta; Bosley, Jim; Marschall, Hanns-Ulrich; Nielsen, Jens; Uhlén, Mathias; Borén, Jan; Mardinoglu, Adil (2020)
    Abstract The prevalence of non-alcoholic fatty liver disease (NAFLD) continues to increase dramatically, and there is no approved medication for its treatment. Recently, we predicted the underlying molecular mechanisms involved in the progression of NAFLD using network analysis and identified metabolic cofactors that might be beneficial as supplements to decrease human liver fat. Here, we first assessed the tolerability of the combined metabolic cofactors including l-serine, N-acetyl-l-cysteine (NAC), nicotinamide riboside (NR), and l-carnitine by performing a 7-day rat toxicology study. Second, we performed a human calibration study by supplementing combined metabolic cofactors and a control study to study the kinetics of these metabolites in the plasma of healthy subjects with and without supplementation. We measured clinical parameters and observed no immediate side effects. Next, we generated plasma metabolomics and inflammatory protein markers data to reveal the acute changes associated with the supplementation of the metabolic cofactors. We also integrated metabolomics data using personalized genome-scale metabolic modeling and observed that such supplementation significantly affects the global human lipid, amino acid, and antioxidant metabolism. Finally, we predicted blood concentrations of these compounds during daily long-term supplementation by generating an ordinary differential equation model and liver concentrations of serine by generating a pharmacokinetic model and finally adjusted the doses of individual metabolic cofactors for future human clinical trials.
  • LITMUS Consortium; Hardy, Timothy; Wonders, Kristy; Younes, Ramy; Aithal, Guruprasad P.; Yki-Järvinen, Hannele (2020)
    Non-Alcoholic Fatty Liver Disease (NAFLD), a progressive liver disease that is closely associated with obesity, type 2 diabetes, hypertension and dyslipidaemia, represents an increasing global public health challenge. There is significant variability in the disease course: the majority exhibit only fat accumulation in the liver but a significant minority develop a necroinflammatory form of the disease (non-alcoholic steatohepatitis, NASH) that may progress to cirrhosis and hepatocellular carcinoma. At present our understanding of pathogenesis, disease natural history and long-term outcomes remain incomplete. There is a need for large, well characterised patient cohorts that may be used to address these knowledge gaps and to support the development of better biomarkers and novel therapies. The European NAFLD Registry is an international, prospectively recruited observational cohort study that aims to establish a large, highly-phenotyped patient cohort and linked bioresource. Here we describe the infrastructure, data management and monitoring plans, and the standard operating procedures implemented to ensure the timely and systematic collection of high-quality data and samples. Already recruiting subjects at secondary/tertiary care centres across Europe, the Registry is supporting the European Union IMI2-funded LITMUS 'Liver Investigation: Testing Marker Utility in Steatohepatitis' consortium, which is a major international effort to robustly validate biomarkers that diagnose, risk stratify and/or monitor NAFLD progression and liver fibrosis stage. The European NAFLD Registry has the demonstrable capacity to support research and biomarker development at scale and pace.
  • Isokuortti, Elina; Zhou, You; Peltonen, Markku; Bugianesi, Elisabetta; Clement, Karine; Bonnefont-Rousselot, Dominique; Lacorte, Jean-Marc; Gastaldelli, Amalia; Schuppan, Detlef; Schattenberg, Joern M.; Hakkarainen, Antti; Lundbom, Nina; Jousilahti, Pekka; Mannisto, Satu; Keinanen-Kiukaanniemi, Sirkka; Saltevo, Juha; Anstee, Quentin M.; Yki-Jarvinen, Hannele (2017)
    Aims/hypothesis Recent European guidelines for nonalcoholic fatty liver disease (NAFLD) call for reference values for HOMA-IR. In this study, we aimed to determine: (1) the upper limit of normal HOMA-IR in two population-based cohorts; (2) the HOMA-IR corresponding to NAFLD; (3) the effect of sex and PNPLA3 genotype at rs738409 on HOMA-IR; and (4) inter-laboratory variations in HOMA-IR. Methods We identified healthy individuals in two population-based cohorts (FINRISK 2007 [n = 5024] and the Programme for Prevention of Type 2 Diabetes in Finland [FIN-D2D; n = 2849]) to define the upper 95th percentile of HOMA-IR. Non-obese individuals with normal fasting glucose levels, no excessive alcohol use, no known diseases and no use of any drugs were considered healthy. The optimal HOMA-IR cut-off for NAFLD (liver fat >= 5.56%, based on the Dallas Heart Study) was determined in 368 non-diabetic individuals (35% with NAFLD), whose liver fat was measured using proton magnetic resonance spectroscopy (1H-MRS). Samples from ten individuals were simultaneously analysed for HOMA-IR in seven European laboratories. Results The upper 95th percentiles of HOMA-IR were 1.9 and 2.0 in healthy individuals in the FINRISK (n = 1167) and FIN-D2D (n = 459) cohorts. Sex or PNPLA3 genotype did not influence these values. The optimal HOMA-IR cutoff for NAFLD was 1.9 (sensitivity 87%, specificity 79%). A HOMA-IR of 2.0 corresponded to normal liver fat ( Conclusions/interpretation The upper limit of HOMA-IR in population-based cohorts closely corresponds to that of normal liver fat. Standardisation of insulin assays would be the first step towards definition of normal values for HOMA-IR.