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Castanho Martins M, Dixon ED, Lupo G, Claudel T, Trauner M, Rombouts K. Role of PNPLA3 in Hepatic Stellate Cells and Hepatic Cellular Crosstalk. Liver Int 2024. [PMID: 39394864 DOI: 10.1111/liv.16117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2024] [Revised: 09/16/2024] [Accepted: 09/17/2024] [Indexed: 10/14/2024]
Abstract
AIMS Since its discovery, the patatin-like phospholipase domain containing 3 (PNPLA3) (rs738409 C>G p.I148M) variant has been studied extensively to unravel its molecular function. Although several studies proved a causal relationship between the PNPLA3 I148M variant and MASLD development and particularly fibrosis, the pathological mechanisms promoting this phenotype have not yet been fully clarified. METHODS We summarise the latest data regarding the PNPLA3 I148M variant in hepatic stellate cells (HSCs) activation and macrophage biology or the path to inflammation-induced fibrosis. RESULTS Elegant but contradictory studies have ascribed PNPLA3 a hydrolase or an acyltransferase function. The PNPLA3 I148M results in hepatic lipid accumulation, which predisposes the hepatocyte to lipotoxicity and lipo-apoptosis, producing DAMPs, cytokines and chemokines leading to recruitment and activation of macrophages and HSCs, propagating fibrosis. Recent studies showed that the PNPLA3 I148M variant alters HSCs biology via attenuation of PPARγ, AP-1, LXRα and TGFβ activity and signalling. CONCLUSIONS The advent of refined techniques in isolating HSCs has made PNPLA3's direct role in HSCs for liver fibrosis development more apparent. However, many other mechanisms still need detailed investigations.
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Affiliation(s)
- Maria Castanho Martins
- Regenerative Medicine and Fibrosis Group, Institute for Liver and Digestive Health, University College London, Royal Free Campus, London, UK
| | - Emmanuel Dauda Dixon
- Hans Popper Laboratory of Molecular Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Giulia Lupo
- Regenerative Medicine and Fibrosis Group, Institute for Liver and Digestive Health, University College London, Royal Free Campus, London, UK
| | - Thierry Claudel
- Hans Popper Laboratory of Molecular Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Michael Trauner
- Hans Popper Laboratory of Molecular Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Krista Rombouts
- Regenerative Medicine and Fibrosis Group, Institute for Liver and Digestive Health, University College London, Royal Free Campus, London, UK
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2
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Vilar-Gomez E, Gawrieh S, Vuppalanchi R, Kettler C, Pike F, Samala N, Chalasani N. PNPLA3 rs738409, environmental factors and liver-related mortality in the U.S. Population. J Hepatol 2024:S0168-8278(24)02617-5. [PMID: 39389267 DOI: 10.1016/j.jhep.2024.09.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 09/23/2024] [Accepted: 09/29/2024] [Indexed: 10/12/2024]
Abstract
BACKGROUND & AIMS Little is known about the interplay between patatin-like phospholipase domain protein 3 (PNPLA3 rs738409 C>G), environmental factors, and the risk of liver-related death (LRD). METHODS 4,361 adults were selected from NHANES III, 1991-1994. All participants were linked to the National Death Index until 2019 (mean follow-up: 23.2 years). LRD was the study outcome. Associations of PNPLA3, diet, light alcohol intake, smoking, and BMI (kg/m2) with LRD were examined using competing risk regression models. RESULTS PNPLA3 G-allele was significantly associated with LRD (adjusted subhazard ratio [adj.sHR]: 2.9, 95% CI: 1.4-5.8). Non-heavy alcohol intake (adj.sHR: 2.2, 95% CI: 1.1-4.5), top quartiles of monounsaturated fat (MUFA) (adj.sHR: 0.43, 95% CI: 0.12-0.99), and cholesterol (adj.sHR: 2.6, 95% CI: 1.00-8.8) and coffee intake ≥3 cups/day (adj.sHR: 0.05, 95% CI: 0.06-0.10), former/current smoking (adj.sHR: 1.8, 95% CI: 1.2-2.6), BMI (adj.sHR: 1.1, 95% CI: 1.03-1.2), and healthy eating index (HEI) (adj.sHR: 0.96, 95% CI: 0.93-0.98) were associated with LRD. Joint effects between PNPLA3 and environmental factors showed that the risk of LRD was significantly increased in carriers of the G-allele with non-heavy alcohol intake (adj.sHR: 3.7), higher consumption (top quartile) of cholesterol (adj.sHR: 4.1), former (adj.sHR: 4.3) or current (adj.sHR: 3.5) smoking, or BMI ≥30 (adj.sHR: 4.0) kg/m2. The effects of the G-allele on the risk of LRD were significantly attenuated in those with top quartile consumption of MUFA (adj.sHR: 0.5) or ≥3 cups/day of coffee (adj.sHR: 0.09). HEI was inversely associated with LRD across all PNPLA3 genotypes (adj.sHR: 0.94, 0.96, and 0.97 for CC, CG, and GG, respectively). CONCLUSIONS PNPLA3 is associated with LRD and this relationship is significantly modified by anthropometric and environmental factors.
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Affiliation(s)
- Eduardo Vilar-Gomez
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Samer Gawrieh
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Raj Vuppalanchi
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Carla Kettler
- Department of Biostatistics, Indiana University School of Medicine, Indianapolis, IN
| | - Francis Pike
- Department of Biostatistics, Indiana University School of Medicine, Indianapolis, IN
| | - Niharika Samala
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Naga Chalasani
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN.
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Xia M, Varmazyad M, Pla-Palacín I, Gavlock DC, DeBiasio R, LaRocca G, Reese C, Florentino RM, Faccioli LAP, Brown JA, Vernetti LA, Schurdak M, Stern AM, Gough A, Behari J, Soto-Gutierrez A, Taylor DL, Miedel MT. Comparison of wild-type and high-risk PNPLA3 variants in a human biomimetic liver microphysiology system for metabolic dysfunction-associated steatotic liver disease precision therapy. Front Cell Dev Biol 2024; 12:1423936. [PMID: 39324073 PMCID: PMC11422722 DOI: 10.3389/fcell.2024.1423936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Accepted: 08/16/2024] [Indexed: 09/27/2024] Open
Abstract
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a worldwide health epidemic with a global occurrence of approximately 30%. The pathogenesis of MASLD is a complex, multisystem disorder driven by multiple factors, including genetics, lifestyle, and the environment. Patient heterogeneity presents challenges in developing MASLD therapeutics, creating patient cohorts for clinical trials, and optimizing therapeutic strategies for specific patient cohorts. Implementing pre-clinical experimental models for drug development creates a significant challenge as simple in vitro systems and animal models do not fully recapitulate critical steps in the pathogenesis and the complexity of MASLD progression. To address this, we implemented a precision medicine strategy that couples the use of our liver acinus microphysiology system (LAMPS) constructed with patient-derived primary cells. We investigated the MASLD-associated genetic variant patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 (I148M variant) in primary hepatocytes as it is associated with MASLD progression. We constructed the LAMPS with genotyped wild-type and variant PNPLA3 hepatocytes, together with key non-parenchymal cells, and quantified the reproducibility of the model. We altered media components to mimic blood chemistries, including insulin, glucose, free fatty acids, and immune-activating molecules to reflect normal fasting (NF), early metabolic syndrome (EMS), and late metabolic syndrome (LMS) conditions. Finally, we investigated the response to treatment with resmetirom, an approved drug for metabolic syndrome-associated steatohepatitis (MASH), the progressive form of MASLD. This study, using primary cells, serves as a benchmark for studies using "patient biomimetic twins" constructed with patient induced pluripotent stem cell (iPSC)-derived liver cells using a panel of reproducible metrics. We observed increased steatosis, immune activation, stellate cell activation, and secretion of pro-fibrotic markers in the PNPLA3 GG variant compared to the wild-type CC LAMPS, consistent with the clinical characterization of this variant. We also observed greater resmetirom efficacy in the PNPLA3 wild-type CC LAMPS compared to the GG variant in multiple MASLD metrics, including steatosis, stellate cell activation, and the secretion of pro-fibrotic markers. In conclusion, our study demonstrates the capability of the LAMPS platform for the development of MASLD precision therapeutics, enrichment of patient cohorts for clinical trials, and optimization of therapeutic strategies for patient subgroups with different clinical traits and disease stages.
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Affiliation(s)
- Mengying Xia
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Mahboubeh Varmazyad
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Iris Pla-Palacín
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Dillon C. Gavlock
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Richard DeBiasio
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Gregory LaRocca
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Celeste Reese
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Rodrigo M. Florentino
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Center for Transcriptional Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Lanuza A. P. Faccioli
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Center for Transcriptional Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jacquelyn A. Brown
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Computational and System Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Lawrence A. Vernetti
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Computational and System Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Mark Schurdak
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Computational and System Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Andrew M. Stern
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Computational and System Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Albert Gough
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jaideep Behari
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
- Division of Gastroenterology, Hepatology and Nutrition, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Alejandro Soto-Gutierrez
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Center for Transcriptional Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - D. Lansing Taylor
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Computational and System Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Mark T. Miedel
- Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, United States
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Walls KM, Joh JY, Hong KU, Hein DW. Heterocyclic Amines Disrupt Lipid Homeostasis in Cryopreserved Human Hepatocytes. Cardiovasc Toxicol 2024; 24:747-756. [PMID: 38851663 PMCID: PMC11300155 DOI: 10.1007/s12012-024-09874-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 05/23/2024] [Indexed: 06/10/2024]
Abstract
Metabolic dysfunction associated-steatotic liver disease (MASLD)/metabolic dysfunction-associated steatohepatitis (MASH) is the liver manifestation of metabolic syndrome, which is characterized by insulin resistance, hyperglycemia, hypertension, dyslipidemia, and/or obesity. Environmental pollutant exposure has been recently identified as a risk factor for developing MASH. Heterocyclic amines (HCAs) are mutagens generated when cooking meat at high temperatures or until well-done. Recent epidemiological studies reported that dietary HCA exposure may be linked to insulin resistance and type II diabetes, and we recently reported that HCAs induce insulin resistance and glucose production in human hepatocytes. However, no previous studies have examined the effects of HCAs on hepatic lipid homeostasis. In the present study, we assessed the effects of two common HCAs, MeIQx (2-amino-3, 8-dimethylimidazo [4, 5-f] quinoxaline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4, 5-b] pyridine), on lipid homeostasis in cryopreserved human hepatocytes. Exposure to a single concentration of 25 μM MeIQx or PhIP in human hepatocytes led to dysregulation of lipid homeostasis, typified by significant increases in lipid droplets and triglycerides. PhIP significantly increased expression of lipid droplet-associated genes, PNPLA3 and HSD17B13, and both HCAs significantly increased PLIN2. Exposure to MeIQx or PhIP also significantly increased expression of several key genes involved in lipid synthesis, transport and metabolism, including FASN, DGAT2, CPT1A, SCD, and CD36. Furthermore, both MeIQx and PhIP significantly increased intracellular cholesterol and decreased expression of PON1 which is involved in cholesterol efflux. Taken together, these results suggest that HCAs dysregulate lipid production, metabolism, and storage. The current study demonstrates, for the first time, that HCA exposure may lead to fat accumulation in hepatocytes, which may contribute to hepatic insulin resistance and MASH.
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Affiliation(s)
- Kennedy M Walls
- Department of Pharmacology and Toxicology and Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA
- Environmental Justice, Community Health and Environmental Review Division, US Environmental Protection Agency, Chicago, USA
| | - Jonathan Y Joh
- Department of Pharmacology and Toxicology and Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Kyung U Hong
- Department of Pharmacology and Toxicology and Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA
- Department of Pharmaceutical and Administrative Sciences, Western New England University, Springfield, USA
| | - David W Hein
- Department of Pharmacology and Toxicology and Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
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Marigorta UM, Millet O, Lu SC, Mato JM. Dysfunctional VLDL metabolism in MASLD. NPJ METABOLIC HEALTH AND DISEASE 2024; 2:16. [PMID: 39049993 PMCID: PMC11263124 DOI: 10.1038/s44324-024-00018-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Accepted: 06/22/2024] [Indexed: 07/27/2024]
Abstract
Lipidomics has unveiled the intricate human lipidome, emphasizing the extensive diversity within lipid classes in mammalian tissues critical for cellular functions. This diversity poses a challenge in maintaining a delicate balance between adaptability to recurring physiological changes and overall stability. Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD), linked to factors such as obesity and diabetes, stems from a compromise in the structural and functional stability of the liver within the complexities of lipid metabolism. This compromise inaccurately senses an increase in energy status, such as during fasting-feeding cycles or an upsurge in lipogenesis. Serum lipidomic studies have delineated three distinct metabolic phenotypes, or "metabotypes" in MASLD. MASLD-A is characterized by lower very low-density lipoprotein (VLDL) secretion and triglyceride (TG) levels, associated with a reduced risk of cardiovascular disease (CVD). In contrast, MASLD-C exhibits increased VLDL secretion and TG levels, correlating with elevated CVD risk. An intermediate subtype, with a blend of features, is designated as the MASLD-B metabotype. In this perspective, we examine into recent findings that show the multifaceted regulation of VLDL secretion by S-adenosylmethionine, the primary cellular methyl donor. Furthermore, we explore the differential CVD and hepatic cancer risk across MASLD metabotypes and discuss the context and potential paths forward to gear the findings from genetic studies towards a better understanding of the observed heterogeneity in MASLD.
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Affiliation(s)
- Urko M. Marigorta
- Integrative Genomics Lab, CIC bioGUNE, Basque Research and Technology Alliance (BRTA), 48160 Derio, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Oscar Millet
- Precision Medicine and Metabolism Lab, CIC bioGUNE, Basque Research and Technology Alliance (BRTA), CIBERehd, 48160 Derio, Spain
| | - Shelly C. Lu
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA
| | - José M. Mato
- Precision Medicine and Metabolism Lab, CIC bioGUNE, Basque Research and Technology Alliance (BRTA), CIBERehd, 48160 Derio, Spain
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Bril F, Kalavalapalli S, Lomonaco R, Frye R, Godinez Leiva E, Cusi K. Insulin resistance is an integral feature of MASLD even in the presence of PNPLA3 variants. JHEP Rep 2024; 6:101092. [PMID: 39022386 PMCID: PMC11252529 DOI: 10.1016/j.jhepr.2024.101092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/29/2024] [Accepted: 04/03/2024] [Indexed: 07/20/2024] Open
Abstract
Background & Aims It has been postulated that carriers of PNPLA3 I148M (CG [Ile/Met] or GG [Met/Met]) develop metabolic dysfunction-associated steatotic liver disease (MASLD) in the absence of insulin resistance or metabolic syndrome. However, the relationship between insulin resistance and MASLD according to the PNPLA3 allele has not been carefully assessed. Methods A total of 204 participants were recruited and underwent PNPLA3 genotyping, an oral glucose tolerance test, liver proton magnetic resonance spectroscopy and percutaneous liver biopsy if diagnosed with MASLD. A subgroup of patients (n = 55) had an euglycemic hyperinsulinemic clamp with glucose tracer infusion. Results As expected, patients with the CG/GG genotype had worse intrahepatic triglyceride content and worse liver histology. However, regardless of PNPLA3 genotype, patients with a diagnosis of MASLD had severe whole-body insulin resistance (Matsuda index, an estimation of insulin resistance in glucose metabolic pathways) and fasting and postprandial adipose tissue insulin resistance (Adipo-IR index and free fatty acid suppression during the oral glucose tolerance test, respectively, as measures of insulin resistance in lipolytic metabolic pathways) compared to patients without MASLD. Moreover, for the same amount of liver fat accumulation, insulin resistance was similar in patients with genotypes CC vs. CG/GG. In multiple regression analyses, A1c and Adipo-IR were associated with the presence of MASLD and advanced liver fibrosis, independently of PNPLA3 genotype. Conclusions PNPLA3 variant carriers with MASLD are equally insulin resistant as non-carriers with MASLD at the level of the liver, muscle, and adipose tissue. This calls for reframing "PNPLA3 MASLD" as an insulin-resistant condition associated with increased hepatic susceptibility to metabolic insults, such as obesity or diabetes, wherein early identification and aggressive intervention are warranted to reverse metabolic dysfunction and prevent disease progression. Impact and implications It has been proposed that the PNPLA3 G allele is associated with the presence of metabolic dysfunction-associated steatotic liver disease (MASLD) in the absence of insulin resistance. However, our results suggest that regardless of PNPLA3 alleles, the presence of insulin resistance is necessary for the development of MASLD. This calls for reframing patients with "PNPLA3 MASLD" not as insulin sensitive, but on the contrary, as an insulin-resistant population with increased hepatic susceptibility to metabolic insults, such as obesity or diabetes.
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Affiliation(s)
- Fernando Bril
- Division of Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham. 510 20 Street South, FOT 825A, 35233, Birmingham, AL, USA
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA. 1600 Archer Road, Room H2, 32610, Gainesville, FL, USA
| | - Srilaxmi Kalavalapalli
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA. 1600 Archer Road, Room H2, 32610, Gainesville, FL, USA
| | - Romina Lomonaco
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA. 1600 Archer Road, Room H2, 32610, Gainesville, FL, USA
| | - Reginald Frye
- Center for Pharmacogenomics, University of Florida, Gainesville, FL, USA; Currently at College of Pharmacy, University of Tennessee Health Science Center, USA
| | - Eddison Godinez Leiva
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA. 1600 Archer Road, Room H2, 32610, Gainesville, FL, USA
| | - Kenneth Cusi
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA. 1600 Archer Road, Room H2, 32610, Gainesville, FL, USA
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Koenig AB, Tan A, Abdelaal H, Monge F, Younossi ZM, Goodman ZD. Review article: Hepatic steatosis and its associations with acute and chronic liver diseases. Aliment Pharmacol Ther 2024; 60:167-200. [PMID: 38845486 DOI: 10.1111/apt.18059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 04/23/2024] [Accepted: 05/13/2024] [Indexed: 06/28/2024]
Abstract
BACKGROUND Hepatic steatosis is a common finding in liver histopathology and the hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), whose global prevalence is rising. AIMS To review the histopathology of hepatic steatosis and its mechanisms of development and to identify common and rare disease associations. METHODS We reviewed literature on the basic science of lipid droplet (LD) biology and clinical research on acute and chronic liver diseases associated with hepatic steatosis using the PubMed database. RESULTS A variety of genetic and environmental factors contribute to the development of chronic hepatic steatosis or steatotic liver disease, which typically appears macrovesicular. Microvesicular steatosis is associated with acute mitochondrial dysfunction and liver failure. Fat metabolic processes in hepatocytes whose dysregulation leads to the development of steatosis include secretion of lipoprotein particles, uptake of remnant lipoprotein particles or free fatty acids from blood, de novo lipogenesis, oxidation of fatty acids, lipolysis and lipophagy. Hepatic insulin resistance is a key feature of MASLD. Seipin is a polyfunctional protein that facilitates LD biogenesis. Assembly of hepatitis C virus takes place on LD surfaces. LDs make important, functional contact with the endoplasmic reticulum and other organelles. CONCLUSIONS Diverse liver pathologies are associated with hepatic steatosis, with MASLD being the most important contributor. The biogenesis and dynamics of LDs in hepatocytes are complex and warrant further investigation. Organellar interfaces permit co-regulation of lipid metabolism to match generation of potentially toxic lipid species with their LD depot storage.
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Affiliation(s)
- Aaron B Koenig
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
| | - Albert Tan
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
| | - Hala Abdelaal
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
| | - Fanny Monge
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
| | - Zobair M Younossi
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- The Global NASH Council, Center for Outcomes Research in Liver Diseases, Washington, DC, USA
| | - Zachary D Goodman
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
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8
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Johnson SM, Bao H, McMahon CE, Chen Y, Burr SD, Anderson AM, Madeyski-Bengtson K, Lindén D, Han X, Liu J. PNPLA3 is a triglyceride lipase that mobilizes polyunsaturated fatty acids to facilitate hepatic secretion of large-sized very low-density lipoprotein. Nat Commun 2024; 15:4847. [PMID: 38844467 PMCID: PMC11156938 DOI: 10.1038/s41467-024-49224-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 05/22/2024] [Indexed: 06/09/2024] Open
Abstract
The I148M variant of PNPLA3 is closely associated with hepatic steatosis. Recent evidence indicates that the I148M mutant functions as an inhibitor of PNPLA2/ATGL-mediated lipolysis, leaving the role of wild-type PNPLA3 undefined. Despite showing a triglyceride hydrolase activity in vitro, PNPLA3 has yet to be established as a lipase in vivo. Here, we show that PNPLA3 preferentially hydrolyzes polyunsaturated triglycerides, mobilizing polyunsaturated fatty acids for phospholipid desaturation and enhancing hepatic secretion of triglyceride-rich lipoproteins. Under lipogenic conditions, mice with liver-specific knockout or acute knockdown of PNPLA3 exhibit aggravated liver steatosis and reduced plasma VLDL-triglyceride levels. Similarly, I148M-knockin mice show decreased hepatic triglyceride secretion during lipogenic stimulation. Our results highlight a specific context whereby the wild-type PNPLA3 facilitates the balance between hepatic triglyceride storage and secretion, and suggest the potential contribution of a loss-of-function by the I148M variant to the development of fatty liver disease in humans.
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Affiliation(s)
- Scott M Johnson
- Department of Biochemistry and Molecular Biology; Mayo Clinic College of Medicine & Science, Rochester, MN, 55905, USA
- Mayo Clinic Graduate School of Biomedical Sciences; Mayo Clinic College of Medicine & Science, Rochester, MN, 55905, USA
- Department of Cell Biology; University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Hanmei Bao
- Barshop Institute for Longevity and Aging Studies and Department of Medicine, Division of Diabetes; University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Cailin E McMahon
- Molecular Biology and Genetics Department; Cornell College of Agriculture and Life Sciences, Ithaca, NY, 14853, USA
| | - Yongbin Chen
- Department of Biochemistry and Molecular Biology; Mayo Clinic College of Medicine & Science, Rochester, MN, 55905, USA
| | - Stephanie D Burr
- Department of Biochemistry and Molecular Biology; Mayo Clinic College of Medicine & Science, Rochester, MN, 55905, USA
| | - Aaron M Anderson
- Department of Developmental Biology; Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA
| | - Katja Madeyski-Bengtson
- Translational Genomics, Discovery Sciences; BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Daniel Lindén
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM); BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
- Division of Endocrinology, Department of Neuroscience and Physiology; Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Xianlin Han
- Barshop Institute for Longevity and Aging Studies and Department of Medicine, Division of Diabetes; University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Jun Liu
- Department of Biochemistry and Molecular Biology; Mayo Clinic College of Medicine & Science, Rochester, MN, 55905, USA.
- Division of Endocrinology, Diabetes, Metabolism and Nutrition; Mayo Clinic in Rochester, Rochester, MN, 55905, USA.
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Babu AF, Palomurto S, Kärjä V, Käkelä P, Lehtonen M, Hanhineva K, Pihlajamäki J, Männistö V. Metabolic signatures of metabolic dysfunction-associated steatotic liver disease in severely obese patients. Dig Liver Dis 2024:S1590-8658(24)00773-4. [PMID: 38825414 DOI: 10.1016/j.dld.2024.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 04/02/2024] [Accepted: 05/13/2024] [Indexed: 06/04/2024]
Abstract
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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Affiliation(s)
- Ambrin Farizah Babu
- School of Medicine, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, 70211 Kuopio, Finland; Afekta Technologies Ltd., Microkatu 1, 70210 Kuopio, Finland
| | - Saana Palomurto
- Department of Surgery, Kuopio University Hospital, 70210 Kuopio, Finland
| | - Vesa Kärjä
- Department of Pathology, Kuopio University Hospital, 70210 Kuopio, Finland
| | - Pirjo Käkelä
- Department of Surgery, Kuopio University Hospital, 70210 Kuopio, Finland
| | - Marko Lehtonen
- School of Pharmacy, Faculty of Health Science, University of Eastern Finland, 70211 Kuopio, Finland; LC-MS Metabolomics Center, Biocenter Kuopio, 70211 Kuopio, Finland
| | - Kati Hanhineva
- School of Medicine, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, 70211 Kuopio, Finland; Afekta Technologies Ltd., Microkatu 1, 70210 Kuopio, Finland; Department of Life Technologies, Food Sciences Unit, University of Turku, 20014 Turku, Finland
| | - Jussi Pihlajamäki
- School of Medicine, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, 70211 Kuopio, Finland; Department of Medicine, Endocrinology and Clinical Nutrition, Kuopio University Hospital, 70210 Kuopio Finland
| | - Ville Männistö
- Department of Medicine, University of Eastern Finland and Kuopio University Hospital, 70210 Kuopio, Finland.
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10
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Tas E, Sundararajan D, Lo JS, Morelli N, Garcia-Reyes Y, Ware MA, Rahat H, Ou X, Na X, Sundaram S, Severn C, Pyle LL, Børsheim E, Vajravelu ME, Muzumdar R, Dranoff JA, Cree MG. Diagnostic Accuracy of Transient Elastography in Hepatosteatosis in Youth With Obesity. J Endocr Soc 2024; 8:bvae110. [PMID: 38895640 PMCID: PMC11185182 DOI: 10.1210/jendso/bvae110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Indexed: 06/21/2024] Open
Abstract
Context Steatotic liver disease is common but overlooked in childhood obesity; diagnostic methods are invasive or expensive. Objective We sought to determine the diagnostic accuracy of vibration-controlled transient elastography (VCTE) compared with magnetic resonance imaging (MRI) in adolescents with obesity and high risk for hepatosteatosis. Methods Baseline data in 3 clinical trials enrolling adolescents with obesity were included (NCT03919929, NCT03717935, NCT04342390). Liver fat was assessed using MRI fat fraction and VCTE-based controlled attenuation parameter (CAP). Hepatosteatosis was defined as MRI fat fraction ≥5.0%. The area under the receiver-operating characteristic curves (AUROCs) for CAP against MRI was calculated, and optimal CAP using the Youden index for hepatosteatosis diagnosis was determined. Results Data from 82 adolescents (age 15.6 ± 1.4 years, body mass index 36.5 ± 5.9 kg/m2, 81% female) were included. Fifty youth had hepatosteatosis by MRI (fat fraction 9.3% ; 95% CI 6.7, 14.0), and 32 participants did not have hepatosteatosis (fat fraction 3.1%; 95% CI 2.2, 3.9; P < .001). The hepatosteatosis group had higher mean CAP compared with no hepatosteatosis (293 dB/m; 95% CI 267, 325 vs 267 dB/m; 95% CI 248, 282; P = .0120). A CAP of 281 dB/m had the highest sensitivity (60%) and specificity (74%) with AUROC of 0.649 (95% CI 0.51-0.79; P = .04) in the entire cohort. In a subset of participants with polycystic ovary syndrome (PCOS), a CAP of 306 dB/m had the highest sensitivity (78%) and specificity (52%) and AUROC of 0.678 (95% CI 0.45-0.90; P = .108). Conclusion CAP of 281 dB/m has modest diagnostic performance for hepatosteatosis compared with MRI in youth with significant obesity. A higher CAP in youth with PCOS suggests that comorbidities might affect optimal CAP in hepatosteatosis diagnosis.
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Affiliation(s)
- Emir Tas
- Pediatric Endocrinology, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
- Center for Childhood Obesity Prevention, Arkansas Children's Research Institute, Little Rock, AR 72202, USA
| | - Divya Sundararajan
- Pediatric Endocrinology, University of Colorado Anschutz, Aurora, CO 80045, USA
| | - Jaclyn S Lo
- Pediatric Endocrinology, University of Colorado Anschutz, Aurora, CO 80045, USA
| | - Nazeen Morelli
- Pediatric Endocrinology, University of Colorado Anschutz, Aurora, CO 80045, USA
| | | | - Meredith A Ware
- Pediatric Endocrinology, University of Colorado Anschutz, Aurora, CO 80045, USA
| | - Haseeb Rahat
- Pediatric Endocrinology, University of Colorado Anschutz, Aurora, CO 80045, USA
| | - Xiawei Ou
- Department of Radiology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Xiaoxu Na
- Department of Radiology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Shikha Sundaram
- Pediatric Gastroenterology, University of Colorado Anschutz, Aurora, CO 80045, USA
| | - Cameron Severn
- Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, CO 80045, USA
| | - Laura L Pyle
- Pediatric Endocrinology, University of Colorado Anschutz, Aurora, CO 80045, USA
- Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, CO 80045, USA
| | - Elisabet Børsheim
- Center for Childhood Obesity Prevention, Arkansas Children's Research Institute, Little Rock, AR 72202, USA
| | - Mary Ellen Vajravelu
- Pediatric Endocrinology, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Radhika Muzumdar
- Pediatric Endocrinology, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Jonathan A Dranoff
- Section of Digestive Diseases, Yale School of Medicine, New Haven, CT 06520, USA
| | - Melanie G Cree
- Pediatric Endocrinology, University of Colorado Anschutz, Aurora, CO 80045, USA
- Ludeman Center for Women's Health, Aurora, CO 80045, USA
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11
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Maurotti S, Geirola N, Frosina M, Mirarchi A, Scionti F, Mare R, Montalcini T, Pujia A, Tirinato L. Exploring the impact of lipid droplets on the evolution and progress of hepatocarcinoma. Front Cell Dev Biol 2024; 12:1404006. [PMID: 38818407 PMCID: PMC11137176 DOI: 10.3389/fcell.2024.1404006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 04/29/2024] [Indexed: 06/01/2024] Open
Abstract
Over the past 10 years, the biological role of lipid droplets (LDs) has gained significant attention in the context of both physiological and pathological conditions. Considerable progress has been made in elucidating key aspects of these organelles, yet much remains to be accomplished to fully comprehend the myriad functions they serve in the progression of hepatic tumors. Our current perception is that LDs are complex and active structures managed by a distinct set of cellular processes. This understanding represents a significant paradigm shift from earlier perspectives. In this review, we aim to recapitulate the function of LDs within the liver, highlighting their pivotal role in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) (Hsu and Loomba, 2024) and their contribution to the progression towards more advanced pathological stages up to hepatocellular carcinoma (HC) (Farese and Walther, 2009). We are aware of the molecular complexity and changes occurring in the neoplastic evolution of the liver. Our attempt, however, is to summarize the most important and recent roles of LDs across both healthy and all pathological liver states, up to hepatocarcinoma. For more detailed insights, we direct readers to some of the many excellent reviews already available in the literature (Gluchowski et al., 2017; Hu et al., 2020; Seebacher et al., 2020; Paul et al., 2022).
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Affiliation(s)
- Samantha Maurotti
- Department of Clinical and Experimental Medicine, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Nadia Geirola
- Department of Clinical and Experimental Medicine, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Miriam Frosina
- Department of Medical and Surgical Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Angela Mirarchi
- Department of Medical and Surgical Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Francesca Scionti
- Department of Clinical and Experimental Medicine, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Rosario Mare
- Department of Medical and Surgical Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Tiziana Montalcini
- Department of Clinical and Experimental Medicine, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Arturo Pujia
- Department of Medical and Surgical Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Luca Tirinato
- Department of Medical and Surgical Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
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12
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Xia M, Varmazyad M, Palacin IP, Gavlock DC, Debiasio R, LaRocca G, Reese C, Florentino R, Faccioli LAP, Brown JA, Vernetti LA, Schurdak ME, Stern AM, Gough A, Behari J, Soto-Gutierrez A, Taylor DL, Miedel M. Comparison of Wild-Type and High-risk PNPLA3 variants in a Human Biomimetic Liver Microphysiology System for Metabolic Dysfunction-associated Steatotic Liver Disease Precision Therapy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.22.590608. [PMID: 38712213 PMCID: PMC11071381 DOI: 10.1101/2024.04.22.590608] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a worldwide health epidemic with a global occurrence of approximately 30%. The pathogenesis of MASLD is a complex, multisystem disorder driven by multiple factors including genetics, lifestyle, and the environment. Patient heterogeneity presents challenges for developing MASLD therapeutics, creation of patient cohorts for clinical trials and optimization of therapeutic strategies for specific patient cohorts. Implementing pre-clinical experimental models for drug development creates a significant challenge as simple in vitro systems and animal models do not fully recapitulate critical steps in the pathogenesis and the complexity of MASLD progression. To address this, we implemented a precision medicine strategy that couples the use of our liver acinus microphysiology system (LAMPS) constructed with patient-derived primary cells. We investigated the MASLD-associated genetic variant PNPLA3 rs738409 (I148M variant) in primary hepatocytes, as it is associated with MASLD progression. We constructed LAMPS with genotyped wild type and variant PNPLA3 hepatocytes together with key non-parenchymal cells and quantified the reproducibility of the model. We altered media components to mimic blood chemistries, including insulin, glucose, free fatty acids, and immune activating molecules to reflect normal fasting (NF), early metabolic syndrome (EMS) and late metabolic syndrome (LMS) conditions. Finally, we investigated the response to treatment with resmetirom, an approved drug for metabolic syndrome-associated steatohepatitis (MASH), the progressive form of MASLD. This study using primary cells serves as a benchmark for studies using patient biomimetic twins constructed with patient iPSC-derived liver cells using a panel of reproducible metrics. We observed increased steatosis, immune activation, stellate cell activation and secretion of pro-fibrotic markers in the PNPLA3 GG variant compared to wild type CC LAMPS, consistent with the clinical characterization of this variant. We also observed greater resmetirom efficacy in PNPLA3 wild type CC LAMPS compared to the GG variant in multiple MASLD metrics including steatosis, stellate cell activation and the secretion of pro-fibrotic markers. In conclusion, our study demonstrates the capability of the LAMPS platform for the development of MASLD precision therapeutics, enrichment of patient cohorts for clinical trials, and optimization of therapeutic strategies for patient subgroups with different clinical traits and disease stages.
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13
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Li Y, Qi P, Song SY, Wang Y, Wang H, Cao P, Liu Y, Wang Y. Elucidating cuproptosis in metabolic dysfunction-associated steatotic liver disease. Biomed Pharmacother 2024; 174:116585. [PMID: 38615611 DOI: 10.1016/j.biopha.2024.116585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/07/2024] [Accepted: 04/10/2024] [Indexed: 04/16/2024] Open
Abstract
Emerging research into metabolic dysfunction-associated steatotic liver disease (MASLD) up until January 2024 has highlighted the critical role of cuproptosis, a unique cell death mechanism triggered by copper overload, in the disease's development. This connection offers new insights into MASLD's complex pathogenesis, pointing to copper accumulation as a key factor that disrupts lipid metabolism and insulin sensitivity. The identification of cuproptosis as a significant contributor to MASLD underscores the potential for targeting copper-mediated pathways for novel therapeutic approaches. This promising avenue suggests that managing copper levels could mitigate MASLD progression, offering a fresh perspective on treatment strategies. Further investigations into how cuproptosis influences MASLD are essential for unraveling the detailed mechanisms at play and for identifying effective interventions. The focus on copper's role in liver health opens up the possibility of developing targeted therapies that address the underlying causes of MASLD, moving beyond symptomatic treatment to tackle the root of the problem. The exploration of cuproptosis in the context of MASLD exemplifies the importance of understanding metal homeostasis in metabolic diseases and represents a significant step forward in the quest for more effective treatments. This research direction lights path for innovative MASLD management and reversal.
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Affiliation(s)
- Yamei Li
- Department of Rehabilitation, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Ping Qi
- Department of Pediatrics, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | | | - Yiping Wang
- Department of Critical Care Medicine, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Hailian Wang
- Clinical Immunology Translational Medicine Key Laboratory of Sichuan Province, Center of Organ Transplantation, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, Chengdu, China
| | - Peng Cao
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
| | - Yu'e Liu
- Tongji University Cancer Center, School of Medicine, Tongji University, Shanghai 200092, China.
| | - Yi Wang
- Department of Critical Care Medicine, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China; Clinical Immunology Translational Medicine Key Laboratory of Sichuan Province, Center of Organ Transplantation, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, Chengdu, China.
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14
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Tian Y, Jellinek MJ, Mehta K, Seok SM, Kuo SH, Lu W, Shi R, Lee R, Lau GW, Kemper JK, Zhang K, Ford DA, Wang B. Membrane phospholipid remodeling modulates nonalcoholic steatohepatitis progression by regulating mitochondrial homeostasis. Hepatology 2024; 79:882-897. [PMID: 36999536 PMCID: PMC10544743 DOI: 10.1097/hep.0000000000000375] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 03/01/2023] [Indexed: 04/01/2023]
Abstract
BACKGROUND AND AIMS NASH, characterized by inflammation and fibrosis, is emerging as a leading etiology of HCC. Lipidomics analyses in the liver have shown that the levels of polyunsaturated phosphatidylcholine (PC) are decreased in patients with NASH, but the roles of membrane PC composition in the pathogenesis of NASH have not been investigated. Lysophosphatidylcholine acyltransferase 3 (LPCAT3), a phospholipid (PL) remodeling enzyme that produces polyunsaturated PLs, is a major determinant of membrane PC content in the liver. APPROACH AND RESULTS The expression of LPCAT3 and the correlation between its expression and NASH severity were analyzed in human patient samples. We examined the effect of Lpcat3 deficiency on NASH progression using Lpcat3 liver-specific knockout (LKO) mice. RNA sequencing, lipidomics, and metabolomics were performed in liver samples. Primary hepatocytes and hepatic cell lines were used for in vitro analyses. We showed that LPCAT3 was dramatically suppressed in human NASH livers, and its expression was inversely correlated with NAFLD activity score and fibrosis stage. Loss of Lpcat3 in mouse liver promotes both spontaneous and diet-induced NASH/HCC. Mechanistically, Lpcat3 deficiency enhances reactive oxygen species production due to impaired mitochondrial homeostasis. Loss of Lpcat3 increases inner mitochondrial membrane PL saturation and elevates stress-induced autophagy, resulting in reduced mitochondrial content and increased fragmentation. Furthermore, overexpression of Lpcat3 in the liver ameliorates inflammation and fibrosis of NASH. CONCLUSIONS These results demonstrate that membrane PL composition modulates the progression of NASH and that manipulating LPCAT3 expression could be an effective therapeutic for NASH.
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Affiliation(s)
- Ye Tian
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Matthew J. Jellinek
- Department of Biochemistry and Molecular Biology, and Center for Cardiovascular Research, Saint Louis University, St. Louis, MO, USA
| | - Kritika Mehta
- Department of Biochemistry, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Sun Mi Seok
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Shanny Hsuan Kuo
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Wei Lu
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ruicheng Shi
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | - Gee W. Lau
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jongsook Kim Kemper
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Kai Zhang
- Department of Biochemistry, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - David A. Ford
- Department of Biochemistry and Molecular Biology, and Center for Cardiovascular Research, Saint Louis University, St. Louis, MO, USA
| | - Bo Wang
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Division of Nutritional Sciences, College of Agricultural, Consumer and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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15
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Dawood RM, Salum GM, Abd El-Meguid M, Fotouh BES. Molecular Insights of Nonalcoholic Fatty Liver Disease Pathogenesis. J Interferon Cytokine Res 2024; 44:111-123. [PMID: 38301145 DOI: 10.1089/jir.2023.0162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is now the most prevalent chronic liver disease. Many hepatic abnormalities are associated with NAFLD such as nonalcoholic steatohepatitis, progressive fibrosis, cirrhosis, and liver failure. Moreover, the pathogenesis of NAFLD has numerous etiologies and can be explained due to the existence of several of stimulus that act simultaneously on genetically susceptible patients. These stimuli include obesity, diabetes, and insulin resistance. In addition, identifying the role of gut microbiota on NAFLD progression has been illustrated. In this review, we clarified the several factors that lead to the development of NAFLD and identify those who are most at risk of developing liver end-stage disease. Highlighting the noninvasive diagnostic NAFLD markers could be helpful in the disease prevention and treatment approaches.
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Affiliation(s)
- Reham Mohammed Dawood
- Department of Microbial Biotechnology, Biotechnology Research Institute, National Research Center, Giza, Egypt
| | - Ghada Maher Salum
- Department of Microbial Biotechnology, Biotechnology Research Institute, National Research Center, Giza, Egypt
| | - Mai Abd El-Meguid
- Department of Microbial Biotechnology, Biotechnology Research Institute, National Research Center, Giza, Egypt
| | - Basma El-Sayed Fotouh
- Department of Microbial Biotechnology, Biotechnology Research Institute, National Research Center, Giza, Egypt
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16
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van Riet S, Julien A, Atanasov A, Nordling Å, Ingelman-Sundberg M. The role of sinusoidal endothelial cells and TIMP1 in the regulation of fibrosis in a novel human liver 3D NASH model. Hepatol Commun 2024; 8:e0374. [PMID: 38358377 PMCID: PMC10871795 DOI: 10.1097/hc9.0000000000000374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 12/16/2023] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND The prevalence of NAFLD is rapidly increasing. NAFLD can progress to NASH, fibrosis, cirrhosis, and HCC, which will soon become the main causes of liver transplantation. To date, no effective drug for NASH has been approved by the Food and Drug Administration. This is partly due to the lack of reliable human in vitro models. Here, we present a novel human liver spheroid model that can be used to study the mechanisms underlying liver fibrosis formation and degradation. METHODS AND RESULTS Such spheroids, which contain hepatocytes, stellate cells, KC, and LSECs, spontaneously develop fibrosis that is exacerbated by treatment with free fatty acids. Conditioned medium from activated LSECs caused similar activation of fibrosis in spheroids containing primary human hepatocyte and NPCs, indicating the action of soluble mediators from the LSECs. Spheroids containing LSECs treated with free fatty acids produced tissue inhibitor of metalloproteinases inhibitor 1, a matrix metalloproteinases inhibitor important for fibrosis progression. Tissue inhibitor of metalloproteinases inhibitor 1 knockdown using siRNA led to a reduction in collagen and procollagen accumulation, which could be partially rescued using a potent matrix metalloproteinases inhibitor. Interestingly, tissue inhibitor of metalloproteinases inhibitor 1 was found to be expressed at higher levels, specifically in a subtype of endothelial cells in the pericentral region of human fibrotic livers, than in control livers. CONCLUSION Potential anti-NASH drugs and compounds were evaluated for their efficacy in reducing collagen accumulation, and we found differences in specificity between spheroids with and without LSECs. This new human NASH model may reveal novel mechanisms for the regulation of liver fibrosis and provide a more appropriate model for screening drugs against NASH.
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Affiliation(s)
- Sander van Riet
- Department of Physiology and Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, Stockholm, Sweden
| | - Anais Julien
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Andrea Atanasov
- Department of Physiology and Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, Stockholm, Sweden
- Department of Physiology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
| | - Åsa Nordling
- Department of Physiology and Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, Stockholm, Sweden
| | - Magnus Ingelman-Sundberg
- Department of Physiology and Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, Stockholm, Sweden
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17
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Tai J, Hsu C, Chen W, Yang S, Chiu C, Chien R, Chang M. Association of liver fibrosis with extrahepatic cancer in steatotic liver disease patients with PNPLA3 I148M GG genotype. Cancer Sci 2024; 115:564-574. [PMID: 38083881 PMCID: PMC10859614 DOI: 10.1111/cas.16042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 02/13/2024] Open
Abstract
The impacts of patatin-like phospholipase domain-containing protein 3 (PNPLA3) I148M-rs738409, methylenetetrahydrofolate reductase (MTHFR) Ala222Val-rs1801133, and aldehyde dehydrogenase 2 (ALDH2) Glu504Lys-rs671 on the outcomes of Taiwanese patients with steatotic liver disease (SLD) have remained elusive. An 8-year prospective cohort study of patients with (n = 546) and without (n = 580) SLD (controls) was undertaken in a Taiwanese tertiary care center. The 546 SLD patients comprised 306 (56.0%) men and 240 (44.0%) women with mean ages of 53.3 and 56.4 years, respectively. Compared with the controls, SLD patients had an increased frequency of the PNPLA3 I148M-rs738409 GG genotype (25.5 vs. 5.9%, p = 0.001). Among the SLD patients, 236 (43.1%) suffered cardiovascular events, 52 (9.5%) showed extrahepatic cancers, 13 (2.38%) experienced hepatic events, including hepatocellular carcinoma (n = 3, 0.5%) and liver cirrhosis (n = 8, 1.47%), and none died. The Fibrosis-4 (FIB-4) scores were associated with extrahepatic cancer (hazard ratio [HR] 1.325; 95% confidence interval [CI], 1.038-1.691) and cirrhosis development (HR 1.532; 95% CI, 1.055-2.224), and the PNPLA3 I148M-rs738409 G allele (β = 0.158, 95% CI, 0.054-0.325) was associated with the FIB-4 score. Stratified analyses showed that the impact of the FIB-4 score on extrahepatic cancer development was evident only in SLD patients with the PNPLA3 I148M-rs738409 GG genotype (HR 1.543; 95% CI, 1.195-1.993) and not in patients with the GC or CC genotype. Moreover, the ALDH2 Glu504Lys-rs671 G allele had a dose-dependent effect on alcoholism, and the MTHFR and ALDH2 genotypes were not significantly associated with SLD patient outcomes. In conclusion, special vigilance should be exercised for emerging extrahepatic cancer in SLD patients with the PNPLA3 I148M-rs738409 GG genotype and high FIB-4 scores.
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Affiliation(s)
- Jennifer Tai
- Department of Medicine, College of MedicineChang Gung UniversityTaoyuanTaiwan
- Department of Gastroenterology and HepatologyChang Gung Memorial HospitalLinkouTaiwan
| | - Chao‐Wei Hsu
- Department of Medicine, College of MedicineChang Gung UniversityTaoyuanTaiwan
- Department of Gastroenterology and HepatologyChang Gung Memorial HospitalLinkouTaiwan
| | - Wei‐Ting Chen
- Department of Medicine, College of MedicineChang Gung UniversityTaoyuanTaiwan
- Department of Gastroenterology and HepatologyChang Gung Memorial HospitalLinkouTaiwan
| | - Sien‐Sing Yang
- Liver Center, Cathay General Hospital Medical CenterTaipeiTaiwan
| | - Cheng‐Hsun Chiu
- Molecular Infectious Disease Research CenterChang Gung Memorial Hospital at LinkouTaoyuanTaiwan
- Division of Pediatric Infectious Diseases, Department of PediatricsChang Gung Memorial Hospital at LinkouTaoyuanTaiwan
| | - Rong‐Nan Chien
- Department of Medicine, College of MedicineChang Gung UniversityTaoyuanTaiwan
- Department of Gastroenterology and HepatologyChang Gung Memorial HospitalLinkouTaiwan
| | - Ming‐Ling Chang
- Department of Medicine, College of MedicineChang Gung UniversityTaoyuanTaiwan
- Department of Gastroenterology and HepatologyChang Gung Memorial HospitalLinkouTaiwan
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18
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Butcko AJ, Putman AK, Mottillo EP. The Intersection of Genetic Factors, Aberrant Nutrient Metabolism and Oxidative Stress in the Progression of Cardiometabolic Disease. Antioxidants (Basel) 2024; 13:87. [PMID: 38247511 PMCID: PMC10812494 DOI: 10.3390/antiox13010087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/06/2023] [Accepted: 01/07/2024] [Indexed: 01/23/2024] Open
Abstract
Cardiometabolic disease (CMD), which encompasses metabolic-associated fatty liver disease (MAFLD), chronic kidney disease (CKD) and cardiovascular disease (CVD), has been increasing considerably in the past 50 years. CMD is a complex disease that can be influenced by genetics and environmental factors such as diet. With the increased reliance on processed foods containing saturated fats, fructose and cholesterol, a mechanistic understanding of how these molecules cause metabolic disease is required. A major pathway by which excessive nutrients contribute to CMD is through oxidative stress. In this review, we discuss how oxidative stress can drive CMD and the role of aberrant nutrient metabolism and genetic risk factors and how they potentially interact to promote progression of MAFLD, CVD and CKD. This review will focus on genetic mutations that are known to alter nutrient metabolism. We discuss the major genetic risk factors for MAFLD, which include Patatin-like phospholipase domain-containing protein 3 (PNPLA3), Membrane Bound O-Acyltransferase Domain Containing 7 (MBOAT7) and Transmembrane 6 Superfamily Member 2 (TM6SF2). In addition, mutations that prevent nutrient uptake cause hypercholesterolemia that contributes to CVD. We also discuss the mechanisms by which MAFLD, CKD and CVD are mutually associated with one another. In addition, some of the genetic risk factors which are associated with MAFLD and CVD are also associated with CKD, while some genetic risk factors seem to dissociate one disease from the other. Through a better understanding of the causative effect of genetic mutations in CMD and how aberrant nutrient metabolism intersects with our genetics, novel therapies and precision approaches can be developed for treating CMD.
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Affiliation(s)
- Andrew J. Butcko
- Hypertension and Vascular Research Division, Henry Ford Hospital, 6135 Woodward Avenue, Detroit, MI 48202, USA; (A.J.B.); (A.K.P.)
- Department of Physiology, Wayne State University, 540 E. Canfield Street, Detroit, MI 48202, USA
| | - Ashley K. Putman
- Hypertension and Vascular Research Division, Henry Ford Hospital, 6135 Woodward Avenue, Detroit, MI 48202, USA; (A.J.B.); (A.K.P.)
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, MI 48823, USA
| | - Emilio P. Mottillo
- Hypertension and Vascular Research Division, Henry Ford Hospital, 6135 Woodward Avenue, Detroit, MI 48202, USA; (A.J.B.); (A.K.P.)
- Department of Physiology, Wayne State University, 540 E. Canfield Street, Detroit, MI 48202, USA
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19
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Bilson J, Mantovani A, Byrne CD, Targher G. Steatotic liver disease, MASLD and risk of chronic kidney disease. DIABETES & METABOLISM 2024; 50:101506. [PMID: 38141808 DOI: 10.1016/j.diabet.2023.101506] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/13/2023] [Accepted: 12/18/2023] [Indexed: 12/25/2023]
Abstract
With the rising tide of fatty liver disease related to metabolic dysfunction worldwide, the association of this common liver disease with chronic kidney disease (CKD) has become increasingly evident. In 2020, the more inclusive term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace the old term non-alcoholic fatty liver disease (NAFLD). In 2023, a modified Delphi process was led by three large pan-national liver associations. There was consensus to change the fatty liver disease nomenclature and definition to include the presence of at least one of five common cardiometabolic risk factors as diagnostic criteria. The name chosen to replace NAFLD was metabolic dysfunction-associated steatotic liver disease (MASLD). The change of nomenclature from NAFLD to MAFLD and then MASLD has resulted in a reappraisal of the epidemiological trends and associations with the risk of developing CKD. The observed association between MAFLD/MASLD and CKD and our understanding that CKD can be an epiphenomenon linked to underlying metabolic dysfunction support the notion that individuals with MASLD are at substantially higher risk of incident CKD than those without MASLD. This narrative review provides an overview of the literature on (a) the evolution of criteria for diagnosing this highly prevalent metabolic liver disease, (b) the epidemiological evidence linking MASLD to the risk of CKD, (c) the underlying mechanisms by which MASLD (and factors strongly linked with MASLD) may increase the risk of developing CKD, and (d) the potential drug treatments that may benefit both MASLD and CKD.
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Affiliation(s)
- Josh Bilson
- School of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK; National Institute for Health and Care Research, Southampton Biomedical Research Centre, University Hospital Southampton and University of Southampton, Southampton, UK
| | - Alessandro Mantovani
- Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Verona, Verona, Italy
| | - Christopher D Byrne
- School of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK; National Institute for Health and Care Research, Southampton Biomedical Research Centre, University Hospital Southampton and University of Southampton, Southampton, UK
| | - Giovanni Targher
- Department of Medicine, University of Verona, Verona, Italy; Metabolic Diseases Research Unit, IRCCS Sacro Cuore - Don Calabria Hospital, Negrar di Valpolicella, Italy.
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20
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Liang N, Harsch BA, Zhou S, Borkowska A, Shearer GC, Kaddurah-Daouk R, Newman JW, Borkowski K. Oxylipin transport by lipoprotein particles and its functional implications for cardiometabolic and neurological disorders. Prog Lipid Res 2024; 93:101265. [PMID: 37979798 DOI: 10.1016/j.plipres.2023.101265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 10/17/2023] [Accepted: 11/13/2023] [Indexed: 11/20/2023]
Abstract
Lipoprotein metabolism is critical to inflammation. While the periphery and central nervous system (CNS) have separate yet connected lipoprotein systems, impaired lipoprotein metabolism is implicated in both cardiometabolic and neurological disorders. Despite the substantial investigation into the composition, structure and function of lipoproteins, the lipoprotein oxylipin profiles, their influence on lipoprotein functions, and their potential biological implications are unclear. Lipoproteins carry most of the circulating oxylipins. Importantly, lipoprotein-mediated oxylipin transport allows for endocrine signaling by these lipid mediators, long considered to have only autocrine and paracrine functions. Alterations in plasma lipoprotein oxylipin composition can directly impact inflammatory responses of lipoprotein metabolizing cells. Similar investigations of CNS lipoprotein oxylipins are non-existent to date. However, as APOE4 is associated with Alzheimer's disease-related microglia dysfunction and oxylipin dysregulation, ApoE4-dependent lipoprotein oxylipin modulation in neurological pathologies is suggested. Such investigations are crucial to bridge knowledge gaps linking oxylipin- and lipoprotein-related disorders in both periphery and CNS. Here, after providing a summary of existent literatures on lipoprotein oxylipin analysis methods, we emphasize the importance of lipoproteins in oxylipin transport and argue that understanding the compartmentalization and distribution of lipoprotein oxylipins may fundamentally alter our consideration of the roles of lipoprotein in cardiometabolic and neurological disorders.
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Affiliation(s)
- Nuanyi Liang
- West Coast Metabolomics Center, Genome Center, University of California Davis, Davis, CA 95616, USA
| | - Brian A Harsch
- Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Sitong Zhou
- Department of Pathology and Laboratory Medicine, University of California Davis, Davis, CA 95616, USA
| | - Alison Borkowska
- Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Gregory C Shearer
- Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Rima Kaddurah-Daouk
- Department of Psychiatry and Behavioral Sciences, Duke Institute for Brain Sciences and Department of Medicine, Duke University, Durham, NC, 27708, USA; Duke Institute of Brain Sciences, Duke University, Durham, NC, USA; Department of Medicine, Duke University, Durham, NC, USA
| | - John W Newman
- West Coast Metabolomics Center, Genome Center, University of California Davis, Davis, CA 95616, USA; Department of Nutrition, University of California - Davis, Davis, CA 95616, USA; Western Human Nutrition Research Center, United States Department of Agriculture - Agriculture Research Service, Davis, CA 95616, USA
| | - Kamil Borkowski
- West Coast Metabolomics Center, Genome Center, University of California Davis, Davis, CA 95616, USA.
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21
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Luukkonen PK, Porthan K, Ahlholm N, Rosqvist F, Dufour S, Zhang XM, Lehtimäki TE, Seppänen W, Orho-Melander M, Hodson L, Petersen KF, Shulman GI, Yki-Järvinen H. The PNPLA3 I148M variant increases ketogenesis and decreases hepatic de novo lipogenesis and mitochondrial function in humans. Cell Metab 2023; 35:1887-1896.e5. [PMID: 37909034 DOI: 10.1016/j.cmet.2023.10.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 06/26/2023] [Accepted: 10/12/2023] [Indexed: 11/02/2023]
Abstract
The PNPLA3 I148M variant is the major genetic risk factor for all stages of fatty liver disease, but the underlying pathophysiology remains unclear. We studied the effect of this variant on hepatic metabolism in homozygous carriers and non-carriers under multiple physiological conditions with state-of-the-art stable isotope techniques. After an overnight fast, carriers had higher plasma β-hydroxybutyrate concentrations and lower hepatic de novo lipogenesis (DNL) compared to non-carriers. After a mixed meal, fatty acids were channeled toward ketogenesis in carriers, which was associated with an increase in hepatic mitochondrial redox state. During a ketogenic diet, carriers manifested increased rates of intrahepatic lipolysis, increased plasma β-hydroxybutyrate concentrations, and decreased rates of hepatic mitochondrial citrate synthase flux. These studies demonstrate that homozygous PNPLA3 I148M carriers have hepatic mitochondrial dysfunction leading to reduced DNL and channeling of carbons to ketogenesis. These findings have implications for understanding why the PNPLA3 variant predisposes to progressive liver disease.
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Affiliation(s)
- Panu K Luukkonen
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Abdominal Center, Helsinki University Hospital, Helsinki, Finland.
| | - Kimmo Porthan
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Noora Ahlholm
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Fredrik Rosqvist
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford & NIHR Oxford Biomedical Research Centre, Oxford University Hospitals Foundation Trust, Oxford, UK; Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden
| | - Sylvie Dufour
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Yale Diabetes Research Center, Yale School of Medicine, New Haven, CT, USA
| | - Xian-Man Zhang
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Yale Diabetes Research Center, Yale School of Medicine, New Haven, CT, USA
| | - Tiina E Lehtimäki
- Department of Radiology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Wenla Seppänen
- Department of Radiology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Marju Orho-Melander
- Department of Clinical Sciences, Diabetes and Endocrinology, University Hospital Malmö, Lund University, Malmö, Sweden
| | - Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford & NIHR Oxford Biomedical Research Centre, Oxford University Hospitals Foundation Trust, Oxford, UK
| | - Kitt Falk Petersen
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Yale Diabetes Research Center, Yale School of Medicine, New Haven, CT, USA
| | - Gerald I Shulman
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Yale Diabetes Research Center, Yale School of Medicine, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA
| | - Hannele Yki-Järvinen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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22
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Dempsey JL, Ioannou GN, Carr RM. Mechanisms of Lipid Droplet Accumulation in Steatotic Liver Diseases. Semin Liver Dis 2023; 43:367-382. [PMID: 37799111 DOI: 10.1055/a-2186-3557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
The steatotic diseases of metabolic dysfunction-associated steatotic liver disease (MASLD), alcohol-associated liver disease (ALD), and chronic hepatitis C (HCV) account for the majority of liver disease prevalence, morbidity, and mortality worldwide. While these diseases have distinct pathogenic and clinical features, dysregulated lipid droplet (LD) organelle biology represents a convergence of pathogenesis in all three. With increasing understanding of hepatocyte LD biology, we now understand the roles of LD proteins involved in these diseases but also how genetics modulate LD biology to either exacerbate or protect against the phenotypes associated with steatotic liver diseases. Here, we review the history of the LD organelle and its biogenesis and catabolism. We also review how this organelle is critical not only for the steatotic phenotype of liver diseases but also for their advanced phenotypes. Finally, we summarize the latest attempts and challenges of leveraging LD biology for therapeutic gain in steatotic diseases. In conclusion, the study of dysregulated LD biology may lead to novel therapeutics for the prevention of disease progression in the highly prevalent steatotic liver diseases of MASLD, ALD, and HCV.
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Affiliation(s)
- Joseph L Dempsey
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of Washington, Seattle, Washington
| | - George N Ioannou
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of Washington, Seattle, Washington
- Division of Gastroenterology, Veterans Affairs Puget Sound Healthcare System Seattle, Washington
| | - Rotonya M Carr
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of Washington, Seattle, Washington
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23
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Pourteymour S, Drevon CA, Dalen KT, Norheim FA. Mechanisms Behind NAFLD: a System Genetics Perspective. Curr Atheroscler Rep 2023; 25:869-878. [PMID: 37812367 DOI: 10.1007/s11883-023-01158-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2023] [Indexed: 10/10/2023]
Abstract
PURPOSE OF REVIEW To summarize the key factors contributing to the onset and progress of nonalcoholic fatty liver disease (NAFLD) and put them in a system genetics context. We particularly focus on how genetic regulation of hepatic lipids contributes to NAFLD. RECENT FINDINGS NAFLD is characterized by excessive accumulation of fat in the liver. This can progress to steatohepatitis (inflammation and hepatocyte injury) and eventually, cirrhosis. The severity of NAFLD is determined by a combination of factors including obesity, insulin resistance, and lipotoxic lipids, along with genetic susceptibility. Numerous studies have been conducted on large human cohorts and mouse panels, to identify key determinants in the genome, transcriptome, proteome, lipidome, microbiome and different environmental conditions contributing to NAFLD. We review common factors contributing to NAFLD and put them in a systems genetics context. In particular, we describe how genetic regulation of liver lipids contributes to NAFLD. The combination of an unhealthy lifestyle and genetic predisposition increases the likelihood of accumulating lipotoxic specie lipids that may be one of the driving forces behind developing severe forms of NAFLD.
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Affiliation(s)
- Shirin Pourteymour
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Blindern, PO Box 1046, 0317, Oslo, Norway
| | - Christian A Drevon
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Blindern, PO Box 1046, 0317, Oslo, Norway
- Vitas Ltd. Oslo Science Park, Oslo, Norway
| | - Knut Tomas Dalen
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Blindern, PO Box 1046, 0317, Oslo, Norway
| | - Frode A Norheim
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Blindern, PO Box 1046, 0317, Oslo, Norway.
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24
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Tian Y, Wang B. Unraveling the pathogenesis of non-alcoholic fatty liver diseases through genome-wide association studies. J Gastroenterol Hepatol 2023; 38:1877-1885. [PMID: 37592846 PMCID: PMC10693931 DOI: 10.1111/jgh.16330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 07/23/2023] [Accepted: 08/02/2023] [Indexed: 08/19/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a significant health burden around the world, affecting approximately 25% of the population. Recent advances in human genetic databases have allowed for the identification of various single nucleotide polymorphisms associated with NAFLD-related traits. Investigating the functions of these genetic factors provides insight into the pathogenesis of NAFLD and potentially identifies novel therapeutic targets for NAFLD. In this review, we summarized current research on genes with NAFLD-associated mutations, highlighting phospholipid remodeling and spatially clustered loci as common pathological and genetic features of these mutations. These features suggest a complex yet intriguing mechanism of dissociated steatosis and insulin resistance, which is observed in a subset of patients and may lead to more precise therapy against NAFLD in the future.
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Affiliation(s)
- Ye Tian
- Department of Comparative Biosciences, College of Veterinary Medicine
| | - Bo Wang
- Department of Comparative Biosciences, College of Veterinary Medicine
- Division of Nutritional Sciences, College of Agricultural, Consumer and Environmental Sciences
- Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
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25
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Hendriks D, Brouwers JF, Hamer K, Geurts MH, Luciana L, Massalini S, López-Iglesias C, Peters PJ, Rodríguez-Colman MJ, Chuva de Sousa Lopes S, Artegiani B, Clevers H. Engineered human hepatocyte organoids enable CRISPR-based target discovery and drug screening for steatosis. Nat Biotechnol 2023; 41:1567-1581. [PMID: 36823355 PMCID: PMC10635827 DOI: 10.1038/s41587-023-01680-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 01/19/2023] [Indexed: 02/25/2023]
Abstract
The lack of registered drugs for nonalcoholic fatty liver disease (NAFLD) is partly due to the paucity of human-relevant models for target discovery and compound screening. Here we use human fetal hepatocyte organoids to model the first stage of NAFLD, steatosis, representing three different triggers: free fatty acid loading, interindividual genetic variability (PNPLA3 I148M) and monogenic lipid disorders (APOB and MTTP mutations). Screening of drug candidates revealed compounds effective at resolving steatosis. Mechanistic evaluation of effective drugs uncovered repression of de novo lipogenesis as the convergent molecular pathway. We present FatTracer, a CRISPR screening platform to identify steatosis modulators and putative targets using APOB-/- and MTTP-/- organoids. From a screen targeting 35 genes implicated in lipid metabolism and/or NAFLD risk, FADS2 (fatty acid desaturase 2) emerged as an important determinant of hepatic steatosis. Enhancement of FADS2 expression increases polyunsaturated fatty acid abundancy which, in turn, reduces de novo lipogenesis. These organoid models facilitate study of steatosis etiology and drug targets.
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Affiliation(s)
- Delilah Hendriks
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, The Netherlands.
- Oncode Institute, Utrecht, The Netherlands.
| | - Jos F Brouwers
- Research Group Analysis Techniques in the Life Sciences, School of Life Sciences and Technology, Avans University of Applied Sciences, Breda, The Netherlands
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Karien Hamer
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, The Netherlands
- Oncode Institute, Utrecht, The Netherlands
| | - Maarten H Geurts
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, The Netherlands
- Oncode Institute, Utrecht, The Netherlands
| | - Léa Luciana
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, The Netherlands
- Oncode Institute, Utrecht, The Netherlands
| | - Simone Massalini
- The Princess Maxima Center for Pediatric Oncology, Utrecht, The Netherlands
| | - Carmen López-Iglesias
- The Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands
| | - Peter J Peters
- The Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands
| | - Maria J Rodríguez-Colman
- Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Benedetta Artegiani
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, The Netherlands.
- The Princess Maxima Center for Pediatric Oncology, Utrecht, The Netherlands.
| | - Hans Clevers
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, The Netherlands.
- Oncode Institute, Utrecht, The Netherlands.
- The Princess Maxima Center for Pediatric Oncology, Utrecht, The Netherlands.
- University Medical Center Utrecht, Utrecht, The Netherlands.
- Pharma, Research and Early Development of F. Hoffmann-La Roche Ltd, Basel, Switzerland.
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26
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Lindén D, Romeo S. Therapeutic opportunities for the treatment of NASH with genetically validated targets. J Hepatol 2023; 79:1056-1064. [PMID: 37207913 DOI: 10.1016/j.jhep.2023.05.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 04/29/2023] [Accepted: 05/02/2023] [Indexed: 05/21/2023]
Abstract
The identification of genetic variants associated with fatty liver disease (FLD) from genome-wide association studies started in 2008 when single nucleotide polymorphisms in PNPLA3, the gene encoding patatin-like phospholipase domain-containing 3, were found to be associated with altered hepatic fat content. Since then, several genetic variants associated with protection from, or an increased risk of, FLD have been identified. The identification of these variants has provided insight into the metabolic pathways that cause FLD and enabled the identification of potential therapeutic targets. In this mini-review, we will examine the therapeutic opportunities derived from genetically validated targets in FLD, including oligonucleotide-based therapies targeting PNPLA3 and HSD17B13 that are currently being evaluated in clinical trials for the treatment of NASH (non-alcoholic steatohepatitis).
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Affiliation(s)
- Daniel Lindén
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden; Division of Endocrinology, Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden.
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden; Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy.
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27
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Johnson S, Bao H, McMahon C, Chen Y, Burr S, Anderson A, Madeyski-Bengtson K, Lindén D, Han X, Liu J. Substrate-Specific Function of PNPLA3 Facilitates Hepatic VLDL-Triglyceride Secretion During Stimulated Lipogenesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.30.553213. [PMID: 37693552 PMCID: PMC10491159 DOI: 10.1101/2023.08.30.553213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
The I148M variant of PNPLA3 is strongly linked to hepatic steatosis. Evidence suggests a gain-of-function role for the I148M mutant as an ATGL inhibitor, leaving the physiological relevance of wild-type PNPLA3 undefined. Here we show that PNPLA3 selectively degrades triglycerides (TGs) enriched in polyunsaturated fatty acids (PUFAs) independently of ATGL in cultured cells and mice. Lipidomics and metabolite tracing analyses demonstrated that PNPLA3 mobilizes PUFAs from intracellular TGs for phospholipid desaturation, supporting hepatic secretion of TG-rich lipoproteins. Consequently, mice with liver-specific knockout or acute knockdown of PNPLA3 both exhibited aggravated liver steatosis and concomitant decreases in plasma VLDL-TG, phenotypes that manifest only under lipogenic conditions. I148M-knockin mice similarly displayed impaired hepatic TG secretion during lipogenic stimulation. Our results highlight a specific context whereby PNPLA3 facilitates the balance between hepatic TG storage and secretion and suggest the potential contributions of I148M variant loss-of-function to the development of hepatic steatosis in humans. Summary Statement We define the physiological role of wild type PNPLA3 in maintaining hepatic VLDL-TG secretion.
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28
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Alonso-Peña M, Del Barrio M, Peleteiro-Vigil A, Jimenez-Gonzalez C, Santos-Laso A, Arias-Loste MT, Iruzubieta P, Crespo J. Innovative Therapeutic Approaches in Non-Alcoholic Fatty Liver Disease: When Knowing Your Patient Is Key. Int J Mol Sci 2023; 24:10718. [PMID: 37445895 DOI: 10.3390/ijms241310718] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/21/2023] [Accepted: 06/24/2023] [Indexed: 07/15/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disorders ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Hepatic steatosis may result from the dysfunction of multiple pathways and thus multiple molecular triggers involved in the disease have been described. The development of NASH entails the activation of inflammatory and fibrotic processes. Furthermore, NAFLD is also strongly associated with several extra-hepatic comorbidities, i.e., metabolic syndrome, type 2 diabetes mellitus, obesity, hypertension, cardiovascular disease and chronic kidney disease. Due to the heterogeneity of NAFLD presentations and the multifactorial etiology of the disease, clinical trials for NAFLD treatment are testing a wide range of interventions and drugs, with little success. Here, we propose a narrative review of the different phenotypic characteristics of NAFLD patients, whose disease may be triggered by different agents and driven along different pathophysiological pathways. Thus, correct phenotyping of NAFLD patients and personalized treatment is an innovative therapeutic approach that may lead to better therapeutic outcomes.
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Affiliation(s)
- Marta Alonso-Peña
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
| | - Maria Del Barrio
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
| | - Ana Peleteiro-Vigil
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
| | - Carolina Jimenez-Gonzalez
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
| | - Alvaro Santos-Laso
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
| | - Maria Teresa Arias-Loste
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
| | - Paula Iruzubieta
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
| | - Javier Crespo
- Gastroenterology and Hepatology Department, Clinical and Translational Research in Digestive Diseases, Valdecilla Research Institute (IDIVAL), Marqués de Valdecilla University Hospital, 39011 Santander, Spain
- Biomedical Research Networking Center in Hepatic and Digestive Diseases (CIBERehd), 28029 Madrid, Spain
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Uehara K, Santoleri D, Whitlock AEG, Titchenell PM. Insulin Regulation of Hepatic Lipid Homeostasis. Compr Physiol 2023; 13:4785-4809. [PMID: 37358513 PMCID: PMC10760932 DOI: 10.1002/cphy.c220015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
The incidence of obesity, insulin resistance, and type II diabetes (T2DM) continues to rise worldwide. The liver is a central insulin-responsive metabolic organ that governs whole-body metabolic homeostasis. Therefore, defining the mechanisms underlying insulin action in the liver is essential to our understanding of the pathogenesis of insulin resistance. During periods of fasting, the liver catabolizes fatty acids and stored glycogen to meet the metabolic demands of the body. In postprandial conditions, insulin signals to the liver to store excess nutrients into triglycerides, cholesterol, and glycogen. In insulin-resistant states, such as T2DM, hepatic insulin signaling continues to promote lipid synthesis but fails to suppress glucose production, leading to hypertriglyceridemia and hyperglycemia. Insulin resistance is associated with the development of metabolic disorders such as cardiovascular and kidney disease, atherosclerosis, stroke, and cancer. Of note, nonalcoholic fatty liver disease (NAFLD), a spectrum of diseases encompassing fatty liver, inflammation, fibrosis, and cirrhosis, is linked to abnormalities in insulin-mediated lipid metabolism. Therefore, understanding the role of insulin signaling under normal and pathologic states may provide insights into preventative and therapeutic opportunities for the treatment of metabolic diseases. Here, we provide a review of the field of hepatic insulin signaling and lipid regulation, including providing historical context, detailed molecular mechanisms, and address gaps in our understanding of hepatic lipid regulation and the derangements under insulin-resistant conditions. © 2023 American Physiological Society. Compr Physiol 13:4785-4809, 2023.
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Affiliation(s)
- Kahealani Uehara
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Dominic Santoleri
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Anna E. Garcia Whitlock
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Paul M. Titchenell
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Tian Y, Mehta K, Jellinek MJ, Sun H, Lu W, Shi R, Ingram K, Friedline RH, Kim JK, Kemper JK, Ford DA, Zhang K, Wang B. Hepatic Phospholipid Remodeling Modulates Insulin Sensitivity and Systemic Metabolism. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2300416. [PMID: 37088778 PMCID: PMC10288282 DOI: 10.1002/advs.202300416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/13/2023] [Indexed: 05/03/2023]
Abstract
The liver plays a central role in regulating glucose and lipid metabolism. Aberrant insulin action in the liver is a major driver of selective insulin resistance, in which insulin fails to suppress glucose production but continues to activate lipogenesis in the liver, resulting in hyperglycemia and hypertriglyceridemia. The underlying mechanisms of selective insulin resistance are not fully understood. Here It is shown that hepatic membrane phospholipid composition controlled by lysophosphatidylcholine acyltransferase 3 (LPCAT3) regulates insulin signaling and systemic glucose and lipid metabolism. Hyperinsulinemia induced by high-fat diet (HFD) feeding augments hepatic Lpcat3 expression and membrane unsaturation. Loss of Lpcat3 in the liver improves insulin resistance and blunts lipogenesis in both HFD-fed and genetic ob/ob mouse models. Mechanistically, Lpcat3 deficiency directly facilitates insulin receptor endocytosis, signal transduction, and hepatic glucose production suppression and indirectly enhances fibroblast growth factor 21 (FGF21) secretion, energy expenditure, and glucose uptake in adipose tissue. These findings identify hepatic LPCAT3 and membrane phospholipid composition as a novel regulator of insulin sensitivity and provide insights into the pathogenesis of selective insulin resistance.
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Affiliation(s)
- Ye Tian
- Department of Comparative BiosciencesCollege of Veterinary MedicineUniversity of Illinois at Urbana‐ChampaignUrbanaIL61802USA
| | - Kritika Mehta
- Department of BiochemistrySchool of Molecular and Cellular BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
| | - Matthew J. Jellinek
- Department of Biochemistry and Molecular Biologyand Center for Cardiovascular ResearchSaint Louis UniversitySt. LouisMO63104USA
| | - Hao Sun
- Department of Molecular and Integrative PhysiologySchool of Molecular and Cellular BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
| | - Wei Lu
- Department of Comparative BiosciencesCollege of Veterinary MedicineUniversity of Illinois at Urbana‐ChampaignUrbanaIL61802USA
| | - Ruicheng Shi
- Department of Comparative BiosciencesCollege of Veterinary MedicineUniversity of Illinois at Urbana‐ChampaignUrbanaIL61802USA
| | - Kevin Ingram
- Department of BiochemistrySchool of Molecular and Cellular BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
| | - Randall H. Friedline
- Program in Molecular Medicine and Division of EndocrinologyMetabolism and DiabetesDepartment of MedicineUniversity of Massachusetts Medical SchoolWorcesterMA01655USA
| | - Jason K. Kim
- Program in Molecular Medicine and Division of EndocrinologyMetabolism and DiabetesDepartment of MedicineUniversity of Massachusetts Medical SchoolWorcesterMA01655USA
| | - Jongsook Kim Kemper
- Department of Molecular and Integrative PhysiologySchool of Molecular and Cellular BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
- Cancer Center at IllinoisUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
| | - David A. Ford
- Department of Biochemistry and Molecular Biologyand Center for Cardiovascular ResearchSaint Louis UniversitySt. LouisMO63104USA
| | - Kai Zhang
- Department of BiochemistrySchool of Molecular and Cellular BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
| | - Bo Wang
- Department of Comparative BiosciencesCollege of Veterinary MedicineUniversity of Illinois at Urbana‐ChampaignUrbanaIL61802USA
- Cancer Center at IllinoisUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
- Division of Nutritional SciencesCollege of AgriculturalConsumer and Environmental SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
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Boeckmans J, Gatzios A, Schattenberg JM, Koek GH, Rodrigues RM, Vanhaecke T. PNPLA3 I148M and response to treatment for hepatic steatosis: A systematic review. Liver Int 2023; 43:975-988. [PMID: 36719059 DOI: 10.1111/liv.15533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 01/25/2023] [Accepted: 01/28/2023] [Indexed: 02/01/2023]
Abstract
BACKGROUND It is unclear whether the patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 C-to-G single nucleotide polymorphism, resulting in the substitution of isoleucine to methionine at position 148 (I148M), impedes regression of hepatic steatosis when treating non-alcoholic fatty liver disease (NAFLD). OBJECTIVES Investigate if carriage of the PNPLA3 148M allele affects the anti-steatotic efficacy of all possible anti-NAFLD interventions, identify gaps in current knowledge and provide guidance for individual treatment. METHODS Research available in public databases was searched up to 13 November 2022. Studies were included if a treatment in NAFLD patients decreased hepatic steatosis in the pooled patient group or a PNPLA3 I148M polymorphism subgroup (II/IM/MM). The risk of bias was assessed using the Cochrane Risk-Of-Bias 2 Tool and the Newcastle-Ottawa Scale. RESULTS Moderate evidence indicates that NAFLD patients homozygous for the PNPLA3 148M allele benefit less or not at all from omega-3 carboxylic acids to decrease liver fat, while the PNPLA3 148I allele shows moderate benefit. Low evidence suggests that interventions employing lifestyle changes are more effective to reduce liver fat in NAFLD patients homozygous for the PNPLA3 148M allele compared to patients with wild-type PNPLA3. CONCLUSIONS NAFLD patients homozygous for the PNPLA3 148M allele might not benefit from omega-3 carboxylic acids to reduce hepatic steatosis in contrast to patients with wild-type PNPLA3. Instead, patients with two PNPLA3 148M alleles should be especially advised to adopt lifestyle changes. Genotyping for PNPLA3 I148M should be encouraged in therapeutic studies for NAFLD. REGISTRATION NUMBER (PROSPERO) CRD42022375028.
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Affiliation(s)
- Joost Boeckmans
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Alexandra Gatzios
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Jörn M Schattenberg
- Metabolic Liver Research Center, Department of Medicine, University Medical Center Mainz, Mainz, Germany
| | - Ger H Koek
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Maastricht University Medical Centre+, Maastricht, The Netherlands
- School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Robim M Rodrigues
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Tamara Vanhaecke
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
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Palasantzas VEJM, Tamargo-Rubio I, Le K, Slager J, Wijmenga C, Jonkers IH, Kumar V, Fu J, Withoff S. iPSC-derived organ-on-a-chip models for personalized human genetics and pharmacogenomics studies. Trends Genet 2023; 39:268-284. [PMID: 36746737 DOI: 10.1016/j.tig.2023.01.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 11/24/2022] [Accepted: 01/12/2023] [Indexed: 02/07/2023]
Abstract
Genome-wide association studies (GWAS) have now correlated hundreds of genetic variants with complex genetic diseases and drug efficacy. Functional characterization of these factors remains challenging, particularly because of the lack of human model systems. Molecular and nanotechnological advances, in particular the ability to generate patient-specific PSC lines, differentiate them into diverse cell types, and seed and combine them on microfluidic chips, have led to the establishment of organ-on-a-chip (OoC) platforms that recapitulate organ biology. OoC technology thus provides unique personalized platforms for studying the effects of host genetics and environmental factors on organ physiology. In this review we describe the technology and provide examples of how OoCs may be used for disease modeling and pharmacogenetic research.
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Affiliation(s)
- Victoria E J M Palasantzas
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Isabel Tamargo-Rubio
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Kieu Le
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jelle Slager
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Cisca Wijmenga
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Iris H Jonkers
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Vinod Kumar
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Internal Medicine and Radboud Centre for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jingyuan Fu
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Sebo Withoff
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
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Luukkonen PK, Färkkilä M, Jula A, Salomaa V, Männistö S, Lundqvist A, Perola M, Åberg F. Abdominal obesity and alcohol use modify the impact of genetic risk for incident advanced liver disease in the general population. Liver Int 2023; 43:1035-1045. [PMID: 36843445 DOI: 10.1111/liv.15554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 02/28/2023]
Abstract
BACKGROUND & AIMS Genetic variants, abdominal obesity and alcohol use are risk factors for incident liver disease (ILD). We aimed to study whether variants either alone or when aggregated into genetic risk scores (GRSs) associate with ILD, and whether waist-hip ratio (WHR) or alcohol use interacts with this risk. METHODS Our study included 33 770 persons (mean age 50 years, 47% men) who participated in health-examination surveys (FINRISK 1992-2012 or Health 2000) with data on alcohol use, WHR and 63 genotypes associated with liver disease. Data were linked with national health registers for liver-related outcomes (hospitalizations, malignancies and death). Exclusions were baseline clinical liver disease. Mean follow-up time was 12.2 years. Cox regression analyses between variants and ILD were adjusted for age, sex and BMI. RESULTS Variants in PNPLA3, IFNL4, TM6SF2, FDFT1, PPP1R3B, SERPINA1 and HSD17B13 were associated with ILD. GRSs calculated from these variants were not associated with WHR or alcohol use, but were exponentially associated with ILD (up to 25-fold higher risk in high versus low score). The risk of ILD in individuals with high GRS and high WHR or alcohol use compared with those with none of these risk factors was increased by up to 90-fold. GRSs provided new prognostic information particularly in individuals with high WHR. CONCLUSIONS The effect of multiple genetic variants on the risk of ILD is potentiated by abdominal obesity and alcohol use. Simple GRSs may help to identify individuals with adverse lifestyle who are at a particularly high risk of ILD.
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Affiliation(s)
- Panu K Luukkonen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland.,Abdominal Center, Helsinki University Hospital, Helsinki, Finland.,Department of Internal Medicine, University of Helsinki, Helsinki, Finland
| | - Martti Färkkilä
- Clinic of Gastroenterology, Helsinki University, Helsinki University Hospital, Helsinki, Finland
| | - Antti Jula
- Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Veikko Salomaa
- Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Satu Männistö
- Finnish Institute for Health and Welfare, Helsinki, Finland
| | | | - Markus Perola
- Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Fredrik Åberg
- Transplantation and Liver Surgery Clinic, Helsinki University Hospital, Helsinki University, Helsinki, Finland
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Danielli M, Perne L, Jarc Jovičić E, Petan T. Lipid droplets and polyunsaturated fatty acid trafficking: Balancing life and death. Front Cell Dev Biol 2023; 11:1104725. [PMID: 36776554 PMCID: PMC9911892 DOI: 10.3389/fcell.2023.1104725] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/17/2023] [Indexed: 01/28/2023] Open
Abstract
Lipid droplets are fat storage organelles ubiquitously distributed across the eukaryotic kingdom. They have a central role in regulating lipid metabolism and undergo a dynamic turnover of biogenesis and breakdown to meet cellular requirements for fatty acids, including polyunsaturated fatty acids. Polyunsaturated fatty acids esterified in membrane phospholipids define membrane fluidity and can be released by the activity of phospholipases A2 to act as ligands for nuclear receptors or to be metabolized into a wide spectrum of lipid signaling mediators. Polyunsaturated fatty acids in membrane phospholipids are also highly susceptible to lipid peroxidation, which if left uncontrolled leads to ferroptotic cell death. On the one hand, lipid droplets act as antioxidant organelles that control polyunsaturated fatty acid storage in triglycerides in order to reduce membrane lipid peroxidation, preserve organelle function and prevent cell death, including ferroptosis. On the other hand, lipid droplet breakdown fine-tunes the delivery of polyunsaturated fatty acids into metabolic and signaling pathways, but unrestricted lipid droplet breakdown may also lead to the release of lethal levels of polyunsaturated fatty acids. Precise regulation of lipid droplet turnover is thus essential for polyunsaturated fatty acid distribution and cellular homeostasis. In this review, we focus on emerging aspects of lipid droplet-mediated regulation of polyunsaturated fatty acid trafficking, including the management of membrane lipid peroxidation, ferroptosis and lipid mediator signaling.
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Affiliation(s)
| | | | | | - Toni Petan
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
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35
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Vasconcellos C, Ferreira O, Lopes MF, Ribeiro AF, Vasques J, Guerreiro CS. Nutritional Genomics in Nonalcoholic Fatty Liver Disease. Biomedicines 2023; 11:biomedicines11020319. [PMID: 36830856 PMCID: PMC9953045 DOI: 10.3390/biomedicines11020319] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 01/24/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common chronic condition associated with genetic and environmental factors in which fat abnormally accumulates in the liver. NAFLD is epidemiologically associated with obesity, type 2 diabetes, and dyslipidemia. Environmental factors, such as physical inactivity and an unbalanced diet, interact with genetic factors, such as epigenetic mechanisms and polymorphisms for the genesis and development of the condition. Different genetic polymorphisms seem to be involved in this context, including variants in PNPLA3, TM6SF2, PEMT, and CHDH genes, playing a role in the disease's susceptibility, development, and severity. From carbohydrate intake and weight loss to omega-3 supplementation and caloric restriction, different dietary and nutritional factors appear to be involved in controlling the onset and progression of NAFLD conditions influencing metabolism, gene, and protein expression. The polygenic risk score represents a sum of trait-associated alleles carried by an individual and seems to be associated with NAFLD outcomes depending on the dietary context. Understanding the exact extent to which lifestyle interventions and genetic predispositions can play a role in the prevention and management of NAFLD can be crucial for the establishment of a personalized and integrative approach to patients.
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Affiliation(s)
- Carolina Vasconcellos
- Laboratório de Nutrição, Faculdade de Medicina, Centro Académico de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Oureana Ferreira
- Laboratório de Nutrição, Faculdade de Medicina, Centro Académico de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Marta Filipa Lopes
- Laboratório de Nutrição, Faculdade de Medicina, Centro Académico de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - André Filipe Ribeiro
- Laboratório de Nutrição, Faculdade de Medicina, Centro Académico de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - João Vasques
- Laboratório de Nutrição, Faculdade de Medicina, Centro Académico de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Catarina Sousa Guerreiro
- Laboratório de Nutrição, Faculdade de Medicina, Centro Académico de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisboa, Portugal
- Instituto de Saúde Ambiental, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
- Correspondence:
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36
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Coassolo L, Liu T, Jung Y, Taylor NP, Zhao M, Charville GW, Nissen SB, Yki-Jarvinen H, Altman RB, Svensson KJ. Mapping transcriptional heterogeneity and metabolic networks in fatty livers at single-cell resolution. iScience 2023; 26:105802. [PMID: 36636354 PMCID: PMC9830221 DOI: 10.1016/j.isci.2022.105802] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/15/2022] [Accepted: 12/09/2022] [Indexed: 12/23/2022] Open
Abstract
Non-alcoholic fatty liver disease is a heterogeneous disease with unclear underlying molecular mechanisms. Here, we perform single-cell RNA sequencing of hepatocytes and hepatic non-parenchymal cells to map the lipid signatures in mice with non-alcoholic fatty liver disease (NAFLD). We uncover previously unidentified clusters of hepatocytes characterized by either high or low srebp1 expression. Surprisingly, the canonical lipid synthesis driver Srebp1 is not predictive of hepatic lipid accumulation, suggestive of other drivers of lipid metabolism. By combining transcriptional data at single-cell resolution with computational network analyses, we find that NAFLD is associated with high constitutive androstane receptor (CAR) expression. Mechanistically, CAR interacts with four functional modules: cholesterol homeostasis, bile acid metabolism, fatty acid metabolism, and estrogen response. Nuclear expression of CAR positively correlates with steatohepatitis in human livers. These findings demonstrate significant cellular differences in lipid signatures and identify functional networks linked to hepatic steatosis in mice and humans.
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Affiliation(s)
- Laetitia Coassolo
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Cardiovascular Institute, Stanford University School of Medicine, CA, USA
| | - Tianyun Liu
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Yunshin Jung
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nikki P. Taylor
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Meng Zhao
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Cardiovascular Institute, Stanford University School of Medicine, CA, USA
| | - Gregory W. Charville
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Silas Boye Nissen
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen N, Denmark
| | - Hannele Yki-Jarvinen
- Department of Medicine, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Russ B. Altman
- Departments of Bioengineering, Genetics & Medicine, Stanford University, Stanford, CA, USA
| | - Katrin J. Svensson
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Cardiovascular Institute, Stanford University School of Medicine, CA, USA
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37
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Park J, Zhao Y, Zhang F, Zhang S, Kwong AC, Zhang Y, Hoffmann HH, Bushweller L, Wu X, Ashbrook AW, Stefanovic B, Chen S, Branch AD, Mason CE, Jung JU, Rice CM, Wu X. IL-6/STAT3 axis dictates the PNPLA3-mediated susceptibility to non-alcoholic fatty liver disease. J Hepatol 2023; 78:45-56. [PMID: 36049612 PMCID: PMC9772150 DOI: 10.1016/j.jhep.2022.08.022] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 07/27/2022] [Accepted: 08/17/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS A number of genetic polymorphisms have been associated with susceptibility to or protection against non-alcoholic fatty liver disease (NAFLD), but the underlying mechanisms remain unknown. Here, we focused on the rs738409 C>G single nucleotide polymorphism (SNP), which produces the I148M variant of patatin-like phospholipase domain-containing protein 3 (PNPLA3) and is strongly associated with NAFLD. METHODS To enable mechanistic dissection, we developed a human pluripotent stem cell (hPSC)-derived multicellular liver culture by incorporating hPSC-derived hepatocytes, hepatic stellate cells, and macrophages. We first applied this liver culture to model NAFLD by utilising a lipotoxic milieu reflecting the circulating levels of disease risk factors in affected individuals. We then created an isogenic pair of liver cultures differing only at rs738049 and compared NAFLD phenotype development. RESULTS Our hPSC-derived liver culture recapitulated many key characteristics of NAFLD development and progression including lipid accumulation and oxidative stress, inflammatory response, and stellate cell activation. Under the lipotoxic conditions, the I148M variant caused the enhanced development of NAFLD phenotypes. These differences were associated with elevated IL-6/signal transducer and activator of transcription 3 (STAT3) activity in liver cultures, consistent with transcriptomic data of liver biopsies from individuals carrying the rs738409 SNP. Dampening IL-6/STAT3 activity alleviated the I148M-mediated susceptibility to NAFLD, whereas boosting it in wild-type liver cultures enhanced NAFLD development. Finally, we attributed this elevated IL-6/STAT3 activity in liver cultures carrying the rs738409 SNP to increased NF-κB activity. CONCLUSIONS Our study thus reveals a potential causal link between elevated IL-6/STAT3 activity and 148M-mediated susceptibility to NAFLD. IMPACT AND IMPLICATIONS An increasing number of genetic variants manifest in non-alcoholic fatty liver disease (NAFLD) development and progression; however, the underlying mechanisms remain elusive. To study these variants in human-relevant systems, we developed an induced pluripotent stem cell-derived multicellular liver culture and focused on a common genetic variant (i.e. rs738409 in PNPLA3). Our findings not only provide mechanistic insight, but also a potential therapeutic strategy for NAFLD driven by this genetic variant in PNPLA3. Our liver culture is therefore a useful platform for exploring genetic variants in NAFLD development.
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Affiliation(s)
- Jiwoon Park
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY, USA; Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA; The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
| | - Yuanyuan Zhao
- Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Fan Zhang
- Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Shaoyan Zhang
- Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Andrew C Kwong
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY, USA; The Biological and Biomedical Sciences Program, Harvard Medical School, Boston, MA, USA
| | - Yujie Zhang
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL, USA
| | - Hans-Heinrich Hoffmann
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY, USA
| | - Leila Bushweller
- Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Xin Wu
- Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Alison W Ashbrook
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY, USA
| | - Branko Stefanovic
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL, USA
| | - Shuyang Chen
- Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Andrea D Branch
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Christopher E Mason
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA; The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
| | - Jae U Jung
- Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Charles M Rice
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY, USA.
| | - Xianfang Wu
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY, USA; Infection Biology Program and Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.
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Hayat U, Siddiqui AA, Farhan ML, Haris A, Hameed N. Genome Editing and Fatty Liver. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1396:191-206. [DOI: 10.1007/978-981-19-5642-3_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Decreased Hyocholic Acid and Lysophosphatidylcholine Induce Elevated Blood Glucose in a Transgenic Porcine Model of Metabolic Disease. Metabolites 2022; 12:metabo12121164. [PMID: 36557202 PMCID: PMC9784658 DOI: 10.3390/metabo12121164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 11/08/2022] [Accepted: 11/11/2022] [Indexed: 11/24/2022] Open
Abstract
(1) Background: This work aims to investigate the metabolomic changes in PIGinH11 pigs and investigate differential compounds as potential therapeutic targets for metabolic diseases. (2) Methods: PIGinH11 pigs were established with a CRISPR/Cas9 system. PNPLA3I148M, hIAPP, and GIPRdn were knocked in the H11 locus of the pig genome. The differential metabolites between and within groups were compared at baseline and two months after high-fat-high-sucrose diet induction. (3) Results: 72.02% of the 815 detected metabolites were affected by the transgenic effect. Significantly increased metabolites included isoleucine, tyrosine, methionine, oxoglutaric acid, acylcarnitine, glucose, sphinganines, ceramides, and phosphatidylserines, while fatty acids and conjugates, phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins were decreased. Lower expression of GPAT3 and higher expression of PNPLA3I148M decreased the synthesis of diacylglycerol and phosphatidylcholines. Accumulated ceramides that block Akt signaling and decrease hyocholic acid and lysophosphatidylcholines might be the main reason for increased blood glucose in PIGinH11 pigs, which was consistent with metabolomic changes in patients. (4) Conclusions: Through serum metabolomics and lipidomics studies, significant changes in obesity and diabetes-related biomarkers were detected in PIGinH11 pigs. Excessive fatty acids β-oxidation interfered with glucose and amino acids catabolism and reduced phosphatidylcholines. Decreased hyocholic acid, lysophosphatidylcholine, and increased ceramides exacerbated insulin resistance and elevated blood glucose. Phosphatidylserines were also increased, which might promote chronic inflammation by activating macrophages.
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40
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NAFLD: genetics and its clinical implications. Clin Res Hepatol Gastroenterol 2022; 46:102003. [PMID: 35963605 DOI: 10.1016/j.clinre.2022.102003] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 07/28/2022] [Accepted: 08/09/2022] [Indexed: 02/04/2023]
Abstract
Worldwide non-alcoholic fatty liver disease (NAFLD) is recognized as the most common type of liver disease and its burden increasing at an alarming rate. NAFLD entails steatosis, fibrosis, cirrhosis, and, finally, hepatocellular carcinoma (HCC). The substantial inter-patient variation during disease progression is the hallmark of individuals with NAFLD. The variability of NAFLD development and related complications among individuals is determined by genetic and environmental factors. Genome-wide association studies (GWAS) have discovered reproducible and robust associations between gene variants such as PNPLA3, TM6SF2, HSD17B13, MBOAT7, GCKR and NAFLD. Evidences have provided the new insights into the NAFLD biology and underlined potential pharmaceutical targets. Ideally, the candidate genes associated with the hereditability of NAFLD are mainly involved in assembly of lipid droplets, lipid remodeling, lipoprotein packing and secretion, redox status mitochondria, and de novo lipogenesis. In recent years, the ability to translate genetics into a clinical context has emerged substantially by combining genetic variants primarily associated with NAFLD into polygenic risk scores (PRS). These score in combination with metabolic factors could be utilized to identify the severe liver diseases in patients with the gene regulatory networks (GRNs). Hereby, we even have highlighted the current understanding related to the schedule therapeutic approach of an individual based on microbial colonization and dysbiosis reversal as a therapy for NAFLD. The premise of this review is to concentrate on the potential of genetic factors and their translation into the design of novel therapeutics, as well as their implications for future research into personalized medications using microbiota.
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Kabbani M, Michailidis E, Steensels S, Fulmer CG, Luna JM, Le Pen J, Tardelli M, Razooky B, Ricardo-Lax I, Zou C, Zeck B, Stenzel AF, Quirk C, Foquet L, Ashbrook AW, Schneider WM, Belkaya S, Lalazar G, Liang Y, Pittman M, Devisscher L, Suemizu H, Theise ND, Chiriboga L, Cohen DE, Copenhaver R, Grompe M, Meuleman P, Ersoy BA, Rice CM, de Jong YP. Human hepatocyte PNPLA3-148M exacerbates rapid non-alcoholic fatty liver disease development in chimeric mice. Cell Rep 2022; 40:111321. [PMID: 36103835 DOI: 10.1016/j.celrep.2022.111321] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 05/11/2022] [Accepted: 08/16/2022] [Indexed: 11/28/2022] Open
Abstract
Advanced non-alcoholic fatty liver disease (NAFLD) is a rapidly emerging global health problem associated with pre-disposing genetic polymorphisms, most strikingly an isoleucine to methionine substitution in patatin-like phospholipase domain-containing protein 3 (PNPLA3-I148M). Here, we study how human hepatocytes with PNPLA3 148I and 148M variants engrafted in the livers of broadly immunodeficient chimeric mice respond to hypercaloric diets. As early as four weeks, mice developed dyslipidemia, impaired glucose tolerance, and steatosis with ballooning degeneration selectively in the human graft, followed by pericellular fibrosis after eight weeks of hypercaloric feeding. Hepatocytes with the PNPLA3-148M variant, either from a homozygous 148M donor or overexpressed in a 148I donor background, developed microvesicular and severe steatosis with frequent ballooning degeneration, resulting in more active steatohepatitis than 148I hepatocytes. We conclude that PNPLA3-148M in human hepatocytes exacerbates NAFLD. These models will facilitate mechanistic studies into human genetic variant contributions to advanced fatty liver diseases.
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Affiliation(s)
- Mohammad Kabbani
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA; Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
| | - Eleftherios Michailidis
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA; Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA 30322, USA
| | - Sandra Steensels
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 413 East 69th Street, BB626, New York, NY 10065, USA
| | - Clifton G Fulmer
- Department of Pathology, Weill Cornell Medicine, New York, NY 10065, USA; Robert J. Tomsich Pathology and Laboratory Medicine Institute, The Cleveland Clinic, Cleveland, OH 44195, USA
| | - Joseph M Luna
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Jérémie Le Pen
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Matteo Tardelli
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 413 East 69th Street, BB626, New York, NY 10065, USA
| | - Brandon Razooky
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Inna Ricardo-Lax
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Chenhui Zou
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA; Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 413 East 69th Street, BB626, New York, NY 10065, USA
| | - Briana Zeck
- Department of Pathology, NYU Langone, New York, NY 10028, USA
| | - Ansgar F Stenzel
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA; Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Corrine Quirk
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | | | - Alison W Ashbrook
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - William M Schneider
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Serkan Belkaya
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, NY 10065, USA
| | - Gadi Lalazar
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 413 East 69th Street, BB626, New York, NY 10065, USA; Laboratory of Cellular Biophysics, The Rockefeller University, New York, NY 10065, USA
| | - Yupu Liang
- Center for Clinical and Translational Science, The Rockefeller University, New York, NY 10065, USA
| | - Meredith Pittman
- Department of Pathology, Weill Cornell Medicine, New York, NY 10065, USA
| | - Lindsey Devisscher
- Department of Basic and Applied Medical Sciences, Gut-Liver Immunopharmacology Unit, Ghent University, Ghent, Belgium
| | | | - Neil D Theise
- Department of Pathology, NYU Langone, New York, NY 10028, USA
| | - Luis Chiriboga
- Department of Pathology, NYU Langone, New York, NY 10028, USA
| | - David E Cohen
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 413 East 69th Street, BB626, New York, NY 10065, USA
| | | | - Markus Grompe
- Yecuris Corporation, Tualatin, OR 97062, USA; Department of Pediatrics, Oregon Stem Cell Center, Oregon Health and Science University, Portland, OR 97239, USA
| | - Philip Meuleman
- Laboratory of Liver Infectious Diseases, Ghent University, Ghent, Belgium
| | - Baran A Ersoy
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 413 East 69th Street, BB626, New York, NY 10065, USA
| | - Charles M Rice
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Ype P de Jong
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA; Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 413 East 69th Street, BB626, New York, NY 10065, USA.
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Hudert CA, Adams LA, Alisi A, Anstee QM, Crudele A, Draijer LG, Furse S, Hengstler JG, Jenkins B, Karnebeek K, Kelly DA, Koot BG, Koulman A, Meierhofer D, Melton PE, Mori TA, Snowden SG, van Mourik I, Vreugdenhil A, Wiegand S, Mann JP. Variants in mitochondrial amidoxime reducing component 1 and hydroxysteroid 17-beta dehydrogenase 13 reduce severity of nonalcoholic fatty liver disease in children and suppress fibrotic pathways through distinct mechanisms. Hepatol Commun 2022; 6:1934-1948. [PMID: 35411667 PMCID: PMC9315139 DOI: 10.1002/hep4.1955] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/19/2022] [Indexed: 12/14/2022] Open
Abstract
Genome-wide association studies in adults have identified variants in hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13) and mitochondrial amidoxime reducing component 1 (MTARC1) as protective against nonalcoholic fatty liver disease (NAFLD). We aimed to test their association with pediatric NAFLD liver histology and investigate their function using metabolomics. A total of 1450 children (729 with NAFLD, 399 with liver histology) were genotyped for rs72613567T>TA in HSD17B13, rs2642438G>A in MTARC1, and rs738409C>G in patatin-like phospholipase domain-containing protein 3 (PNPLA3). Genotype-histology associations were tested using ordinal regression. Untargeted hepatic proteomics and plasma lipidomics were performed in a subset of children. We found rs72613567T>TA in HSD17B13 to be associated with lower odds of NAFLD diagnosis (odds ratio, 0.7; 95% confidence interval, 0.6-0.9) and a lower grade of portal inflammation (p < 0.001). rs2642438G>A in MTARC1 was associated with a lower grade of hepatic steatosis (p = 0.02). Proteomics found reduced expression of HSD17B13 in carriers of the protective -TA allele. MTARC1 levels were unaffected by genotype. Both variants were associated with down-regulation of fibrogenic pathways. HSD17B13 perturbs plasma phosphatidylcholines and triglycerides. In silico modeling suggested p.Ala165Thr disrupts the stability and metal binding of MTARC1. Conclusion: Both HSD17B13 and MTARC1 variants are associated with less severe pediatric NAFLD. These results provide further evidence for shared genetic mechanisms between pediatric and adult NAFLD.
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Affiliation(s)
- Christian A Hudert
- Department of Pediatric Gastroenterology, Nephrology and Metabolic DiseasesCharité Universitätsmedizin BerlinBerlinGermany
| | - Leon A Adams
- Medical SchoolUniversity of Western AustraliaPerthAustralia.,Department of HepatologySir Charles Gairdner HospitalPerthAustralia
| | - Anna Alisi
- Research Unit of Molecular Genetics of Complex PhenotypesBambino Gesù Children's Hospital-Istituto di Ricovero e Cura a Carattere ScientificoRomeItaly
| | - Quentin M Anstee
- 5994Translational and Clinical Research InstituteFaculty of Medical SciencesNewcastle UniversityNewcastle upon TyneUK.,Newcastle National Institute for Health Research Biomedical Research CentreNewcastle upon Tyne Hospitals National Health Service Foundation TrustNewcastle upon TyneUK
| | - Annalisa Crudele
- Research Unit of Molecular Genetics of Complex PhenotypesBambino Gesù Children's Hospital-Istituto di Ricovero e Cura a Carattere ScientificoRomeItaly
| | - Laura G Draijer
- Department of Pediatric Gastroenterology and NutritionAmsterdam University Medical CenterEmma Children's HospitalUniversity of AmsterdamAmsterdamthe Netherlands
| | - Samuel Furse
- Core Metabolomics and Lipidomics LaboratoryWellcome Trust-Medical Research Council Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | - Jan G Hengstler
- Systems ToxicologyLeibniz Research Center for Working Environment and Human Factors at the Technical University DortmundDortmundGermany
| | - Benjamin Jenkins
- Core Metabolomics and Lipidomics LaboratoryWellcome Trust-Medical Research Council Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | - Kylie Karnebeek
- Center for Overweight Adolescent and Children's Health CareDepartment of PediatricsMaastricht University Medical CenterMaastrichtthe Netherlands
| | - Deirdre A Kelly
- Liver UnitBirmingham Womens and Children's Hospital TrustBirminghamUK
| | - Bart G Koot
- Department of Pediatric Gastroenterology and NutritionAmsterdam University Medical CenterEmma Children's HospitalUniversity of AmsterdamAmsterdamthe Netherlands
| | - Albert Koulman
- Core Metabolomics and Lipidomics LaboratoryWellcome Trust-Medical Research Council Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | - David Meierhofer
- Max Planck Institute for Molecular GeneticsMass Spectrometry FacilityBerlinGermany
| | - Phillip E Melton
- School of Global Population HealthFaculty of Health and Medical SciencesUniversity of Western AustraliaPerthAustralia.,School of Pharmacy and Biomedical SciencesFaculty of Health SciencesCurtin UniversityPerthAustralia.,Menzies Institute for Medical ResearchCollege of Health and MedicineUniversity of TasmaniaHobartAustralia
| | - Trevor A Mori
- Medical SchoolUniversity of Western AustraliaPerthAustralia
| | - Stuart G Snowden
- Core Metabolomics and Lipidomics LaboratoryWellcome Trust-Medical Research Council Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | - Indra van Mourik
- Liver UnitBirmingham Womens and Children's Hospital TrustBirminghamUK
| | - Anita Vreugdenhil
- Center for Overweight Adolescent and Children's Health CareDepartment of PediatricsMaastricht University Medical CenterMaastrichtthe Netherlands
| | - Susanna Wiegand
- Center for Chronically Sick ChildrenCharité Universitätsmedizin BerlinBerlinGermany
| | - Jake P Mann
- 2152Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
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Dearlove DJ, Hodson L. Intrahepatic triglyceride content: influence of metabolic and genetics drivers. Curr Opin Clin Nutr Metab Care 2022; 25:241-247. [PMID: 35762159 DOI: 10.1097/mco.0000000000000838] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Intrahepatic triglyceride (IHTG) content is determined by substrate flux to, fatty acid synthesis and partitioning within, and triglyceride disposal from the liver. Dysregulation of these processes may cause IHTG accumulation, potentially leading to nonalcoholic fatty liver disease. The aetiology of IHTG accumulation has not been fully elucidated; however, environmental factors and heritability are important. Here, we review recent evidence regarding the contribution of metabolic and genetic components of IHTG accumulation. RECENT FINDINGS Obesity and insulin resistance are the primary metabolic drivers for IHTG accumulation. These risk factors have pronounced and seemingly overlapping effects on all processes involved in determining IHTG content. The strong and interchangeable associations between obesity, insulin resistance and IHTG make it challenging to determine their relative contributions. Genome-wide association studies have identified a growing list of single nucleotide polymorphisms associated with IHTG content and recent work has begun to elucidate their mechanistic effects. The mechanisms underlying metabolic and genetic drivers of IHTG appear to be distinct. SUMMARY Both metabolic and genetic factors influence IHTG content by apparently distinct mechanisms. Further work is needed to determine metabolic and genetic interaction effects, which may lead to more personalized and potentially efficacious therapeutic interventions. The development of a comprehensive polygenic risk score for IHTG content may help facilitate this.
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Affiliation(s)
- David J Dearlove
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford
| | - Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford
- Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK
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44
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Patsenker E, Thangapandi VR, Knittelfelder O, Palladini A, Hefti M, Beil-Wagner J, Rogler G, Buch T, Shevchenko A, Hampe J, Stickel F. The Pnpla3 Variant I148M Reveals Protective Effects Towards Hepatocellular Carcinoma in Mice via Restoration of Omega-3 Polyunsaturated Fats. J Nutr Biochem 2022; 108:109081. [PMID: 35691594 DOI: 10.1016/j.jnutbio.2022.109081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 02/02/2022] [Accepted: 05/03/2022] [Indexed: 12/02/2022]
Abstract
Alcohol consumption and high caloric diet are leading causes of progressive fatty liver disease. Genetic variant rs738409 in patatin-like phospholipase domain-containing protein 3 (PNPLA3 rs738409 C>G) has been repeatedly described as one of the major risk loci for alcoholic liver cirrhosis (ALC) and hepatocellular carcinoma (HCC) in humans, however, the mechanism behind this association is incompletely understood. We generated mice carrying the rs738409 variant (PNPLA3 I148M) in order to detect genotype-phenotype relationships in mice upon chow and alcohol-high fat/high sugar diet (EtOH/WD). We could clearly demonstrate that the presence of rs738409 per se is sufficient to induce spontaneous development of steatosis after one year in mice on a chow diet, whereas in the setting of unhealthy diet feeding, PNPLA3 I148M did not affect hepatic inflammation or fibrosis, but induced a striking lipid remodelling, microvesicular steatosis and protected from HCC formation. Using shot gun lipidomics, we detected a striking restoration of reduced long chain-polyunsaturated fatty acids (LC-PUFA)-containing TGs, docosapentaenoic acid (C22:5 n3) and omega-3-derived eicosanoids (5-HEPE, 20-HEPE, 19,20-EDP, 21-HDHA) in PNPLA3 I148M mice upon EtOH/WD. At the molecular level, PNPLA3 I148M modulated enzymes for fatty acid and TG transport and metabolism. These findings suggest (dietary) lipids as an important and independent driver of hepatic tumorigenesis. Genetic variant in PNPLA3 exerted protective effects in mice, conflicting with findings in humans. Species-related differences in physiology and metabolism should be taken into account when modelling unhealthy human lifestyle, as genetic mouse models may not always allow for translation of insight gained in humans.
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Affiliation(s)
- Eleonora Patsenker
- Department of Gastroenterology and Hepatology, University of Zurich, 8091 Zurich, Switzerland.
| | - Veera Raghavan Thangapandi
- Department of Gastroenterology and Hepatology, Universitätsklinikum Dresden, 01304 Dresden, Germany; Center for Regenerative Therapies, TU Dresden, 01307 Dresden, Germany
| | - Oskar Knittelfelder
- Max Plank Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Alessandra Palladini
- Paul Langerhans Institute Dresden of the Helmholtz Zentrum München at the University Hospital and Faculty of Medicine Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; German Center for Diabetes Research, 85764 Neuherberg, Germany
| | - Michaela Hefti
- Department of Gastroenterology and Hepatology, University of Zurich, 8091 Zurich, Switzerland
| | - Jane Beil-Wagner
- Institute of Laboratory Animal Science, University of Zurich, 8952 Schlieren, Switzerland
| | - Gerhard Rogler
- Department of Gastroenterology and Hepatology, University of Zurich, 8091 Zurich, Switzerland
| | - Thorsten Buch
- Institute of Laboratory Animal Science, University of Zurich, 8952 Schlieren, Switzerland
| | - Andrej Shevchenko
- Max Plank Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Jochen Hampe
- Department of Gastroenterology and Hepatology, Universitätsklinikum Dresden, 01304 Dresden, Germany; Center for Regenerative Therapies, TU Dresden, 01307 Dresden, Germany
| | - Felix Stickel
- Department of Gastroenterology and Hepatology, University of Zurich, 8091 Zurich, Switzerland
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Velenosi TJ, Ben-Yakov G, Podszun MC, Hercun J, Etzion O, Yang S, Nadal C, Haynes-Williams V, Huang WCA, Gonzalez-Hodar L, Brychta RJ, Takahashi S, Akkaraju V, Krausz KW, Walter M, Cai H, Walter PJ, Muniyappa R, Chen KY, Gonzalez FJ, Rotman Y. Postprandial Plasma Lipidomics Reveal Specific Alteration of Hepatic-derived Diacylglycerols in Nonalcoholic Fatty Liver Disease. Gastroenterology 2022; 162:1990-2003. [PMID: 35283114 PMCID: PMC9117487 DOI: 10.1053/j.gastro.2022.03.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 02/24/2022] [Accepted: 03/01/2022] [Indexed: 01/04/2023]
Abstract
BACKGROUND & AIMS Hepatic energy metabolism is a dynamic process modulated by multiple stimuli. In nonalcoholic fatty liver disease (NAFLD), human studies typically focus on the static fasting state. We hypothesized that unique postprandial alterations in hepatic lipid metabolism are present in NAFLD. METHODS In a prospective clinical study, 37 patients with NAFLD and 10 healthy control subjects ingested a standardized liquid meal with pre- and postprandial blood sampling. Postprandial plasma lipid kinetics were characterized at the molecular lipid species level by untargeted lipidomics, cluster analysis, and lipid particle isolation, then confirmed in a mouse model. RESULTS There was a specific increase of multiple plasma diacylglycerol (DAG) species at 4 hours postprandially in patients with NAFLD but not in controls. This was replicated in a nonalcoholic steatohepatitis mouse model, where postprandial DAGs increased in plasma and concomitantly decreased in the liver. The increase in plasma DAGs appears early in the disease course, is dissociated from NAFLD severity and obesity, and correlates with postprandial insulin levels. Immunocapture isolation of very low density lipoprotein in human samples and stable isotope tracer studies in mice revealed that elevated postprandial plasma DAGs reflect hepatic secretion of endogenous, rather than meal-derived lipids. CONCLUSIONS We identified a selective insulin-related increase in hepatic secretion of endogenously derived DAGs after a mixed meal as a unique feature of NAFLD. DAGs are known to be lipotoxic and associated with atherosclerosis. Although it is still unknown whether the increased exposure to hepatic DAGs contributes to extrahepatic manifestations and cardiovascular risk in NAFLD, our study highlights the importance of extending NAFLD research beyond the fasting state.
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Affiliation(s)
- Thomas J. Velenosi
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH)
| | - Gil Ben-Yakov
- Liver & Energy Metabolism Section, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH,Liver Diseases Branch, NIDDK, NIH
| | - Maren C. Podszun
- Liver & Energy Metabolism Section, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH,Liver Diseases Branch, NIDDK, NIH
| | | | | | | | | | | | | | - Lila Gonzalez-Hodar
- Liver & Energy Metabolism Section, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH,Liver Diseases Branch, NIDDK, NIH
| | | | - Shogo Takahashi
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH)
| | - Vikas Akkaraju
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH)
| | - Kristopher W. Krausz
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH)
| | | | - Hongyi Cai
- Clinical Mass Spectrometry Core, NIDDK, NIH
| | | | | | - Kong Y. Chen
- Diabetes, Endocrinology and Obesity Branch, NIDDK, NIH
| | - Frank J. Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH)
| | - Yaron Rotman
- Liver and Energy Metabolism Section, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland; Liver Diseases Branch, NIDDK, NIH, Bethesda, Maryland.
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Uehara K, Sostre-Colón J, Gavin M, Santoleri D, Leonard KA, Jacobs RL, Titchenell PM. Activation of Liver mTORC1 Protects Against NASH via Dual Regulation of VLDL-TAG Secretion and De Novo Lipogenesis. Cell Mol Gastroenterol Hepatol 2022; 13:1625-1647. [PMID: 35240344 PMCID: PMC9046248 DOI: 10.1016/j.jcmgh.2022.02.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 01/07/2023]
Abstract
BACKGROUND & AIMS Dysregulation of liver lipid metabolism is associated with the development and progression of nonalcoholic fatty liver disease, a spectrum of liver diseases including nonalcoholic steatohepatitis (NASH). In the liver, insulin controls lipid homeostasis by increasing triglyceride (TAG) synthesis, suppressing fatty acid oxidation, and enhancing TAG export via very low-density lipoproteins. Downstream of insulin signaling, the mechanistic target of rapamycin complex 1 (mTORC1), is a key regulator of lipid metabolism. Here, we define the role of hepatic mTORC1 activity in mouse models of NASH and investigate the mTORC1-dependent mechanisms responsible for protection against liver damage in NASH. METHODS Utilizing 2 rodent NASH-promoting diets, we demonstrate that hepatic mTORC1 activity was reduced in mice with NASH, whereas under conditions of insulin resistance and benign fatty liver, mTORC1 activity was elevated. To test the beneficial effects of hepatic mTORC1 activation in mouse models of NASH, we employed an acute, liver-specific knockout model of TSC1 (L-TSC-KO), a negative regulator of mTORC1. RESULTS L-TSC-KO mice are protected from and have improved markers of NASH including reduced steatosis, decreased circulating transaminases, and reduced expression of inflammation and fibrosis genes. Mechanistically, protection from hepatic inflammation and fibrosis by constitutive mTORC1 activity occurred via promotion of the phosphatidylcholine synthesizing enzyme, CCTα, and enhanced very low-density lipoprotein-triglyceride export. Additionally, activation of mTORC1 protected from hepatic steatosis via negative feedback of the mTORC2-AKT-FOXO-SREBP1c lipogenesis axis. CONCLUSIONS Collectively, this study identifies a protective role for liver mTORC1 signaling in the initiation and progression of NASH in mice via dual control of lipid export and synthesis.
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Affiliation(s)
- Kahealani Uehara
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jaimarie Sostre-Colón
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Matthew Gavin
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Dominic Santoleri
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kelly-Ann Leonard
- Department of Agricultural, Food and Nutritional Science Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - René L Jacobs
- Department of Agricultural, Food and Nutritional Science Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Paul M Titchenell
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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Therapeutic RNA-silencing oligonucleotides in metabolic diseases. Nat Rev Drug Discov 2022; 21:417-439. [PMID: 35210608 DOI: 10.1038/s41573-022-00407-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2022] [Indexed: 12/14/2022]
Abstract
Recent years have seen unprecedented activity in the development of RNA-silencing oligonucleotide therapeutics for metabolic diseases. Improved oligonucleotide design and optimization of synthetic nucleic acid chemistry, in combination with the development of highly selective and efficient conjugate delivery technology platforms, have established and validated oligonucleotides as a new class of drugs. To date, there are five marketed oligonucleotide therapies, with many more in clinical studies, for both rare and common liver-driven metabolic diseases. Here, we provide an overview of recent developments in the field of oligonucleotide therapeutics in metabolism, review past and current clinical trials, and discuss ongoing challenges and possible future developments.
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Hsieh J, Molusky MM, McCabe KM, Fotakis P, Xiao T, Tascau L, Zeana-Schliep L, DaSilva-Jardine P, Tall AR. TTC39B destabilizes retinoblastoma protein promoting hepatic lipogenesis in a sex-specific fashion. J Hepatol 2022; 76:383-393. [PMID: 34600974 PMCID: PMC8766887 DOI: 10.1016/j.jhep.2021.09.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND & AIMS Molecular mechanisms underlying the different susceptibility of men and women to non-alcoholic fatty liver disease (NAFLD) are poorly understood. The TTC39B locus encodes a scaffolding protein, associates with gynecological disorders and its deletion protects mice from diet-induced steatohepatitis. This study aimed to elucidate the molecular mechanisms linking TTC39B (T39) to the expression of lipogenic genes and to explore sex-specific effects. METHODS Co-expression in HEK293A cells validated the novel T39/pRb interaction predicted by a protein-protein interaction algorithm. T39 was knocked down using an antisense oligonucleotide (ASO) in mice with dietary NAFLD and a genetic deficiency of pRb or its downstream effector E2F1, as well as in primary human hepatocytes. RESULTS T39 interacts with pRb via its C-terminal TPR domain and promotes its proteasomal degradation. In female mice, T39 deficiency reduces the mRNA of lipogenic genes, especially Pnpla3, in a pRb- and E2F1-dependent manner. In contrast, in male mice, T39 deficiency results in a much smaller reduction in lipogenic gene expression that is independent of pRb/E2F1. T39 also interacts with VAPB via an N-terminal FFAT motif and stabilizes the interaction of VAPB with SCAP. Ovariectomy abolishes the effect of T39 knockdown on the hepatic pRb/E2F1/Pnpla3 axis. In both sexes T39 knockdown reduces SCAP independently of pRb. In primary human hepatocytes, T39 knockdown reduces expression of PNPLA3 and other lipogenic genes in women but not men. CONCLUSIONS We have uncovered a conserved sexual dimorphism in the regulation of hepatic lipogenic genes, with effects of T39 mediated through pRb/E2F1 in females and VAPB/SCAP in both sexes. T39 inhibition could be a novel strategy to downregulate PNPLA3 and treat NAFLD in women. LAY SUMMARY In females, the protein TTC39B degrades a tumor suppressor in the liver to promote the synthesis of new fat and the expression of a major genetic risk factor for non-alcoholic fatty liver disease. TTC39B is a potential therapeutic target for non-alcoholic fatty liver disease, especially in women.
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Affiliation(s)
- Joanne Hsieh
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA.
| | - Matthew M. Molusky
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA
| | - Kristin M. McCabe
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA
| | - Panagiotis Fotakis
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA
| | - Tong Xiao
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA
| | - Liana Tascau
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA
| | - Lars Zeana-Schliep
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA
| | | | - Alan R. Tall
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, 10032, USA
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Gatzios A, Rombaut M, Buyl K, De Kock J, Rodrigues RM, Rogiers V, Vanhaecke T, Boeckmans J. From NAFLD to MAFLD: Aligning Translational In Vitro Research to Clinical Insights. Biomedicines 2022; 10:biomedicines10010161. [PMID: 35052840 PMCID: PMC8773802 DOI: 10.3390/biomedicines10010161] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/09/2022] [Accepted: 01/10/2022] [Indexed: 11/16/2022] Open
Abstract
Although most same-stage non-alcoholic fatty liver disease (NAFLD) patients exhibit similar histologic sequelae, the underlying mechanisms appear to be highly heterogeneous. Therefore, it was recently proposed to redefine NAFLD to metabolic dysfunction-associated fatty liver disease (MAFLD) in which other known causes of liver disease such as alcohol consumption or viral hepatitis do not need to be excluded. Revised nomenclature envisions speeding up and facilitating anti-MAFLD drug development by means of patient stratification whereby each subgroup would benefit from distinct pharmacological interventions. As human-based in vitro research fulfils an irrefutable step in drug development, action should be taken as well in this stadium of the translational path. Indeed, most established in vitro NAFLD models rely on short-term exposure to fatty acids and use lipid accumulation as a phenotypic benchmark. This general approach to a seemingly ambiguous disease such as NAFLD therefore no longer seems applicable. Human-based in vitro models that accurately reflect distinct disease subgroups of MAFLD should thus be adopted in early preclinical disease modeling and drug testing. In this review article, we outline considerations for setting up translational in vitro experiments in the MAFLD era and allude to potential strategies to implement MAFLD heterogeneity into an in vitro setting so as to better align early drug development with future clinical trial designs.
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Affiliation(s)
| | | | | | | | | | | | | | - Joost Boeckmans
- Correspondence: (A.G.); (J.B.); Tel.: +32-(0)-2-477-45-94 (A.G.)
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Cherubini A, Casirati E, Tomasi M, Valenti L. PNPLA3 as a therapeutic target for fatty liver disease: the evidence to date. Expert Opin Ther Targets 2021; 25:1033-1043. [PMID: 34904923 DOI: 10.1080/14728222.2021.2018418] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION An interaction between metabolic triggers and inherited predisposition underpins the development and progression of non alcoholic fatty liver disease (NAFLD) and fatty liver disease in general. Among the specific NAFLD risk variants, PNPLA3 rs738409 C>G, encoding for the p.I148M protein variant, accounts for the largest fraction of liver disease heritability and is being intensively scrutinized. It promotes intrahepatic lipid accumulation and is associated with lipotoxicity and the more severe phenotypes, including fibrosis and carcinogenesis. Therefore, PNPLA3 appears as an appealing therapeutic target to counter NAFLD progression. AREAS COVERED The scope of this review is to briefly describe the PNPLA3 gene and protein function before discussing therapeutic approaches for fatty liver aiming at this target. Literature review was carried out searching through PubMed and clinicaltrials.gov website and focusing on the most recent works and reviews. EXPERT OPINION The main therapeutic strategies under development for NAFLD have shown variable efficacy and side-effects likely due to disease heterogeneity and lack of engagement of the main pathogenic drivers of liver disease. To overcome these limitations, new strategies are becoming available for targeting PNPLA3 p.I148M, responsible for a large fraction of disease susceptibility.
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Affiliation(s)
- Alessandro Cherubini
- Precision Medicine - Department of Transfusion Medicine and Hematology, Fondazione Irccs Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Elia Casirati
- Department of Pathophysiology and Transplantation, Università Degli Studi Di Milano, Milan, Italy
| | - Melissa Tomasi
- Precision Medicine - Department of Transfusion Medicine and Hematology, Fondazione Irccs Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Luca Valenti
- Precision Medicine - Department of Transfusion Medicine and Hematology, Fondazione Irccs Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Pathophysiology and Transplantation, Università Degli Studi Di Milano, Milan, Italy
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