1
|
Sookoian S, Rotman Y, Valenti L. Genetics of Metabolic Dysfunction-associated Steatotic Liver Disease: The State of Art Update. Clin Gastroenterol Hepatol 2024:S1542-3565(24)00690-6. [PMID: 39094912 DOI: 10.1016/j.cgh.2024.05.052] [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: 01/12/2024] [Revised: 04/18/2024] [Accepted: 05/28/2024] [Indexed: 08/04/2024]
Abstract
Recent advances in the genetics of metabolic dysfunction-associated steatotic liver disease (MASLD) are gradually revealing the mechanisms underlying the heterogeneity of the disease and have shown promising results in patient stratification. Genetic characterization of the disease has been rapidly developed using genome-wide association studies, exome-wide association studies, phenome-wide association studies, and whole exome sequencing. These advances have been powered by the increase in computational power, the development of new analytical algorithms, including some based on artificial intelligence, and the recruitment of large and well-phenotyped cohorts. This review presents an update on genetic studies that emphasize new biological insights from next-generation sequencing approaches. Additionally, we discuss innovative methods for discovering new genetic loci for MASLD, including rare variants. To comprehensively manage MASLD, it is important to stratify risks. Therefore, we present an update on phenome-wide association study associations, including extreme phenotypes. Additionally, we discuss whether polygenic risk scores and targeted sequencing are ready for clinical use. With particular focus on precision medicine, we introduce concepts such as the interplay between genetics and the environment in modulating genetic risk with lifestyle or standard therapies. A special chapter is dedicated to gene-based therapeutics. The limitations of approved pharmacological approaches are discussed, and the potential of gene-related mechanisms in therapeutic development is reviewed, including the decision to perform genetic testing in patients with MASLD.
Collapse
Affiliation(s)
- Silvia Sookoian
- Clinical and Molecular Hepatology, Translational Health Research Center (CENITRES), Maimónides University, Buenos Aires, Argentina; Faculty of Health Science, Maimónides University, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
| | - Yaron Rotman
- Liver & Energy Metabolism Section, Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Luca Valenti
- Precision Medicine - Department of Transfusion Medicine, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| |
Collapse
|
2
|
Chandrasekaran P, Weiskirchen S, Weiskirchen R. Perilipins: A family of five fat-droplet storing proteins that play a significant role in fat homeostasis. J Cell Biochem 2024; 125:e30579. [PMID: 38747370 DOI: 10.1002/jcb.30579] [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: 02/27/2024] [Revised: 04/18/2024] [Accepted: 04/30/2024] [Indexed: 06/12/2024]
Abstract
Lipid droplets are organelles with unique spherical structures. They consist of a hydrophobic neutral lipid core that varies depending on the cell type and tissue. These droplets are surrounded by phospholipid monolayers, along with heterogeneous proteins responsible for neutral lipid synthesis and metabolism. Additionally, there are specialized lipid droplet-associated surface proteins. Recent evidence suggests that proteins from the perilipin family (PLIN) are associated with the surface of lipid droplets and are involved in their formation. These proteins have specific roles in hepatic lipid droplet metabolism, such as protecting the lipid droplets from lipase action and maintaining a balance between lipid storage and utilization in specific cells. Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by the accumulation of lipid droplets in more than 5% of the hepatocytes. This accumulation can progress into metabolic dysfunction-associated steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. The accumulation of hepatic lipid droplets in the liver is associated with the progression of MASLD and other diseases such as sarcopenic obesity. Therefore, it is crucial to understand the role of perilipins in this accumulation, as these proteins are key targets for developing novel therapeutic strategies. This comprehensive review aims to summarize the structure and characteristics of PLIN proteins, as well as their pathogenic role in the development of hepatic steatosis and fatty liver diseases.
Collapse
Affiliation(s)
| | - Sabine Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), Rheinisch-Westfälische Technische Hochschule (RWTH), University Hospital Aachen, Aachen, Germany
| | - Ralf Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), Rheinisch-Westfälische Technische Hochschule (RWTH), University Hospital Aachen, Aachen, Germany
| |
Collapse
|
3
|
Korbecki J, Bosiacki M, Pilarczyk M, Gąssowska-Dobrowolska M, Jarmużek P, Szućko-Kociuba I, Kulik-Sajewicz J, Chlubek D, Baranowska-Bosiacka I. Phospholipid Acyltransferases: Characterization and Involvement of the Enzymes in Metabolic and Cancer Diseases. Cancers (Basel) 2024; 16:2115. [PMID: 38893234 PMCID: PMC11171337 DOI: 10.3390/cancers16112115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/23/2024] [Accepted: 05/28/2024] [Indexed: 06/21/2024] Open
Abstract
This review delves into the enzymatic processes governing the initial stages of glycerophospholipid (phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine) and triacylglycerol synthesis. The key enzymes under scrutiny include GPAT and AGPAT. Additionally, as most AGPATs exhibit LPLAT activity, enzymes participating in the Lands cycle with similar functions are also covered. The review begins by discussing the properties of these enzymes, emphasizing their specificity in enzymatic reactions, notably the incorporation of polyunsaturated fatty acids (PUFAs) such as arachidonic acid and docosahexaenoic acid (DHA) into phospholipids. The paper sheds light on the intricate involvement of these enzymes in various diseases, including obesity, insulin resistance, and cancer. To underscore the relevance of these enzymes in cancer processes, a bioinformatics analysis was conducted. The expression levels of the described enzymes were correlated with the overall survival of patients across 33 different types of cancer using the GEPIA portal. This review further explores the potential therapeutic implications of inhibiting these enzymes in the treatment of metabolic diseases and cancer. By elucidating the intricate enzymatic pathways involved in lipid synthesis and their impact on various pathological conditions, this paper contributes to a comprehensive understanding of these processes and their potential as therapeutic targets.
Collapse
Affiliation(s)
- Jan Korbecki
- Department of Anatomy and Histology, Collegium Medicum, University of Zielona Góra, Zyty 28, 65-046 Zielona Góra, Poland;
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (M.B.); (D.C.)
| | - Mateusz Bosiacki
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (M.B.); (D.C.)
| | - Maciej Pilarczyk
- Department of Nervous System Diseases, Neurosurgery Center University Hospital in Zielona Góra, Collegium Medicum, University of Zielona Gora, 65-417 Zielona Góra, Poland; (M.P.); (P.J.)
| | - Magdalena Gąssowska-Dobrowolska
- Department of Cellular Signalling, Mossakowski Medical Research Institute, Polish Academy of Sciences, Pawińskiego 5, 02-106 Warsaw, Poland;
| | - Paweł Jarmużek
- Department of Nervous System Diseases, Neurosurgery Center University Hospital in Zielona Góra, Collegium Medicum, University of Zielona Gora, 65-417 Zielona Góra, Poland; (M.P.); (P.J.)
| | | | - Justyna Kulik-Sajewicz
- Department of Conservative Dentistry and Endodontics, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland;
| | - Dariusz Chlubek
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (M.B.); (D.C.)
| | - Irena Baranowska-Bosiacka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (M.B.); (D.C.)
| |
Collapse
|
4
|
Moore MP, Wang X, Kennelly JP, Shi H, Ishino Y, Kano K, Aoki J, Cherubini A, Ronzoni L, Guo X, Chalasani NP, Khalid S, Saleheen D, Mitsche MA, Rotter JI, Yates KP, Valenti L, Kono N, Tontonoz P, Tabas I. Low MBOAT7 expression, a genetic risk for MASH, promotes a profibrotic pathway involving hepatocyte TAZ upregulation. Hepatology 2024:01515467-990000000-00886. [PMID: 38776184 DOI: 10.1097/hep.0000000000000933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 04/03/2024] [Indexed: 05/24/2024]
Abstract
BACKGROUND AND AIMS The common genetic variant rs641738 C>T is a risk factor for metabolic dysfunction-associated steatotic liver disease and metabolic dysfunction-associated steatohepatitis (MASH), including liver fibrosis, and is associated with decreased expression of the phospholipid-remodeling enzyme MBOAT7 (LPIAT1). However, whether restoring MBOAT7 expression in established metabolic dysfunction-associated steatotic liver disease dampens the progression to liver fibrosis and, importantly, the mechanism through which decreased MBOAT7 expression exacerbates MASH fibrosis remain unclear. APPROACH AND RESULTS We first showed that hepatocyte MBOAT7 restoration in mice with diet-induced steatohepatitis slows the progression to liver fibrosis. Conversely, when hepatocyte-MBOAT7 was silenced in mice with established hepatosteatosis, liver fibrosis but not hepatosteatosis was exacerbated. Mechanistic studies revealed that hepatocyte-MBOAT7 restoration in MASH mice lowered hepatocyte-TAZ (WWTR1), which is known to promote MASH fibrosis. Conversely, hepatocyte-MBOAT7 silencing enhanced TAZ upregulation in MASH. Finally, we discovered that changes in hepatocyte phospholipids due to MBOAT7 loss-of-function promote a cholesterol trafficking pathway that upregulates TAZ and the TAZ-induced profibrotic factor Indian hedgehog (IHH). As evidence for relevance in humans, we found that the livers of individuals with MASH carrying the rs641738-T allele had higher hepatocyte nuclear TAZ, indicating higher TAZ activity and increased IHH mRNA. CONCLUSIONS This study provides evidence for a novel mechanism linking MBOAT7-LoF to MASH fibrosis, adds new insight into an established genetic locus for MASH, and, given the druggability of hepatocyte TAZ for MASH fibrosis, suggests a personalized medicine approach for subjects at increased risk for MASH fibrosis due to inheritance of variants that lower MBOAT7.
Collapse
Affiliation(s)
- Mary P Moore
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - Xiaobo Wang
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - John Paul Kennelly
- Department of Pathology and Laboratory Medicine, Molecular Biology Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | - Hongxue Shi
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - Yuki Ishino
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Kuniyuki Kano
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Alessandro Cherubini
- Precisione Medicine Lab, Biological Resource Center and Department of Transfusion Medicine, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Milan, Italy
| | - Luisa Ronzoni
- Precisione Medicine Lab, Biological Resource Center and Department of Transfusion Medicine, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Milan, Italy
| | - Xiuqing Guo
- The Institute for Translational Genomics and Population Sciences, Department of Pediatrics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | - Naga P Chalasani
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Shareef Khalid
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
- Center for Non-Communicable Disease, Karachi, Karachi City, Sindh, Pakistan
| | - Danish Saleheen
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
- Center for Non-Communicable Disease, Karachi, Karachi City, Sindh, Pakistan
| | - Matthew A Mitsche
- Center for Human Nutrition and Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jerome I Rotter
- The Institute for Translational Genomics and Population Sciences, Department of Pediatrics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | - Katherine P Yates
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Luca Valenti
- Precisione Medicine Lab, Biological Resource Center and Department of Transfusion Medicine, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Milan, Italy
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milano, Italy
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Peter Tontonoz
- Department of Pathology and Laboratory Medicine, Molecular Biology Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | - Ira Tabas
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, New York, USA
- Columbia University Digestive and Liver Disease Research Center, New York, NY
| |
Collapse
|
5
|
Varadharajan V, Ramachandiran I, Massey WJ, Jain R, Banerjee R, Horak AJ, McMullen MR, Huang E, Bellar A, Lorkowski SW, Gulshan K, Helsley RN, James I, Pathak V, Dasarathy J, Welch N, Dasarathy S, Streem D, Reizes O, Allende DS, Smith JD, Simcox J, Nagy LE, Brown JM. Membrane-bound O-acyltransferase 7 (MBOAT7) shapes lysosomal lipid homeostasis and function to control alcohol-associated liver injury. eLife 2024; 12:RP92243. [PMID: 38648183 PMCID: PMC11034944 DOI: 10.7554/elife.92243] [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] [Indexed: 04/25/2024] Open
Abstract
Recent genome-wide association studies (GWAS) have identified a link between single-nucleotide polymorphisms (SNPs) near the MBOAT7 gene and advanced liver diseases. Specifically, the common MBOAT7 variant (rs641738) associated with reduced MBOAT7 expression is implicated in non-alcoholic fatty liver disease (NAFLD), alcohol-associated liver disease (ALD), and liver fibrosis. However, the precise mechanism underlying MBOAT7-driven liver disease progression remains elusive. Previously, we identified MBOAT7-driven acylation of lysophosphatidylinositol lipids as key mechanism suppressing the progression of NAFLD (Gwag et al., 2019). Here, we show that MBOAT7 loss of function promotes ALD via reorganization of lysosomal lipid homeostasis. Circulating levels of MBOAT7 metabolic products are significantly reduced in heavy drinkers compared to healthy controls. Hepatocyte- (Mboat7-HSKO), but not myeloid-specific (Mboat7-MSKO), deletion of Mboat7 exacerbates ethanol-induced liver injury. Lipidomic profiling reveals a reorganization of the hepatic lipidome in Mboat7-HSKO mice, characterized by increased endosomal/lysosomal lipids. Ethanol-exposed Mboat7-HSKO mice exhibit dysregulated autophagic flux and lysosomal biogenesis, associated with impaired transcription factor EB-mediated lysosomal biogenesis and autophagosome accumulation. This study provides mechanistic insights into how MBOAT7 influences ALD progression through dysregulation of lysosomal biogenesis and autophagic flux, highlighting hepatocyte-specific MBOAT7 loss as a key driver of ethanol-induced liver injury.
Collapse
Affiliation(s)
- Venkateshwari Varadharajan
- Department of Cancer Biology, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Iyappan Ramachandiran
- Department of Cancer Biology, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - William J Massey
- Department of Cancer Biology, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Raghav Jain
- Department of Biochemistry, University of Wisconsin-MadisonMadisonUnited States
| | - Rakhee Banerjee
- Department of Cancer Biology, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Anthony J Horak
- Department of Cancer Biology, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Megan R McMullen
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Emily Huang
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Annette Bellar
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Shuhui W Lorkowski
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
| | - Kailash Gulshan
- Center for Gene Regulation in Health and Disease (GRHD), Cleveland State UniversityClevelandUnited States
| | - Robert N Helsley
- Department of Cancer Biology, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
- Department of Pharmacology & Nutritional Sciences, Saha Cardiovascular Research Center, University of Kentucky College of MedicineLexingtonUnited States
| | - Isabella James
- Department of Biochemistry, University of Wisconsin-MadisonMadisonUnited States
| | - Vai Pathak
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Jaividhya Dasarathy
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Family Medicine, Metro Health Medical Center, Case Western Reserve UniversityClevelandUnited States
| | - Nicole Welch
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Srinivasan Dasarathy
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - David Streem
- Lutheran Hospital, Cleveland ClinicClevelandUnited States
| | - Ofer Reizes
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - Daniela S Allende
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Anatomical Pathology, Cleveland ClinicClevelandUnited States
| | - Jonathan D Smith
- Department of Cancer Biology, Lerner Research Institute of the Cleveland ClinicClevelandUnited States
| | - Judith Simcox
- Department of Biochemistry, University of Wisconsin-MadisonMadisonUnited States
| | - Laura E Nagy
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland ClinicClevelandUnited States
| | - J Mark Brown
- Center for Microbiome and Human Health, Lerner Research Institute, Cleveland ClinicClevelandUnited States
- Northern Ohio Alcohol Center (NOAC), Lerner Research Institute, Cleveland ClinicClevelandUnited States
| |
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Montero-Vallejo R, Maya-Miles D, Ampuero J, Martín F, Romero-Gómez M, Gallego-Durán R. Novel insights into metabolic-associated steatotic liver disease preclinical models. Liver Int 2024; 44:644-662. [PMID: 38291855 DOI: 10.1111/liv.15830] [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: 07/13/2023] [Revised: 12/02/2023] [Accepted: 12/18/2023] [Indexed: 02/01/2024]
Abstract
Metabolic-associated steatotic liver disease (MASLD) encompasses a wide spectrum of metabolic conditions associated with an excess of fat accumulation in the liver, ranging from simple hepatic steatosis to cirrhosis and hepatocellular carcinoma. Finding appropriate tools to study its development and progression is essential to address essential unmet therapeutic and staging needs. This review discusses advantages and shortcomings of different dietary, chemical and genetic factors that can be used to mimic this disease and its progression in mice from a hepatic and metabolic point of view. Also, this review will highlight some additional factors and considerations that could have a strong impact on the outcomes of our model to end up providing recommendations and a checklist to facilitate the selection of the appropriate MASLD preclinical model based on clinical aims.
Collapse
Affiliation(s)
- Rocío Montero-Vallejo
- SeLiver Group, Instituto de Biomedicina de Sevilla/CSIC/Hospital Virgen del Rocío, Sevilla, Spain
- Hepatic and Digestive Diseases Networking Biomedical Research Centre (CIBERehd), Sevilla, Spain
| | - Douglas Maya-Miles
- SeLiver Group, Instituto de Biomedicina de Sevilla/CSIC/Hospital Virgen del Rocío, Sevilla, Spain
- Hepatic and Digestive Diseases Networking Biomedical Research Centre (CIBERehd), Sevilla, Spain
| | - Javier Ampuero
- SeLiver Group, Instituto de Biomedicina de Sevilla/CSIC/Hospital Virgen del Rocío, Sevilla, Spain
- Hepatic and Digestive Diseases Networking Biomedical Research Centre (CIBERehd), Sevilla, Spain
- Digestive Diseases Unit, Hospital Universitario Virgen Del Rocío, Sevilla, Spain
| | - Franz Martín
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, University Pablo Olavide-University of Seville-CSIC, Seville, Spain
- Biomedical Research Network on Diabetes and Related Metabolic Diseases-CIBERDEM, Instituto de Salud Carlos III, Madrid, Spain
| | - Manuel Romero-Gómez
- SeLiver Group, Instituto de Biomedicina de Sevilla/CSIC/Hospital Virgen del Rocío, Sevilla, Spain
- Hepatic and Digestive Diseases Networking Biomedical Research Centre (CIBERehd), Sevilla, Spain
- Digestive Diseases Unit, Hospital Universitario Virgen Del Rocío, Sevilla, Spain
| | - Rocío Gallego-Durán
- SeLiver Group, Instituto de Biomedicina de Sevilla/CSIC/Hospital Virgen del Rocío, Sevilla, Spain
- Hepatic and Digestive Diseases Networking Biomedical Research Centre (CIBERehd), Sevilla, Spain
| |
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Varadharajan V, Ramachandiran L, Massey WJ, Jain R, Banerjee R, Horak AJ, McMullen MR, Huang E, Bellar A, Lorkowski SW, Guilshan K, Helsley RN, James I, Pathak V, Dasarathy J, Welch N, Dasarathy S, Streem D, Reizes O, Allende DS, Smith JD, Simcox J, Nagy LE, Brown JM. Membrane Bound O-Acyltransferase 7 (MBOAT7) Shapes Lysosomal Lipid Homeostasis and Function to Control Alcohol-Associated Liver Injury. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.26.559533. [PMID: 37808828 PMCID: PMC10557709 DOI: 10.1101/2023.09.26.559533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Several recent genome-wide association studies (GWAS) have identified single nucleotide polymorphism (SNPs) near the gene encoding membrane-bound O -acyltransferase 7 ( MBOAT7 ) that is associated with advanced liver diseases. In fact, a common MBOAT7 variant (rs641738), which is associated with reduced MBOAT7 expression, confers increased susceptibility to non-alcoholic fatty liver disease (NAFLD), alcohol-associated liver disease (ALD), and liver fibrosis in those chronically infected with hepatitis viruses B and C. The MBOAT7 gene encodes a lysophosphatidylinositol (LPI) acyltransferase enzyme that produces the most abundant form of phosphatidylinositol 38:4 (PI 18:0/20:4). Although these recent genetic studies clearly implicate MBOAT7 function in liver disease progression, the mechanism(s) by which MBOAT7-driven LPI acylation regulates liver disease is currently unknown. Previously we showed that antisense oligonucleotide (ASO)-mediated knockdown of Mboat7 promoted non-alcoholic fatty liver disease (NAFLD) in mice (Helsley et al., 2019). Here, we provide mechanistic insights into how MBOAT7 loss of function promotes alcohol-associated liver disease (ALD). In agreement with GWAS studies, we find that circulating levels of metabolic product of MBOAT7 (PI 38:4) are significantly reduced in heavy drinkers compared to age-matched healthy controls. Hepatocyte specific genetic deletion ( Mboat7 HSKO ), but not myeloid-specific deletion ( Mboat7 MSKO ), of Mboat7 in mice results in enhanced ethanol-induced hepatic steatosis and high concentrations of plasma alanine aminotransferase (ALT). Given MBOAT7 is a lipid metabolic enzyme, we performed comprehensive lipidomic profiling of the liver and identified a striking reorganization of the hepatic lipidome upon ethanol feeding in Mboat7 HSKO mice. Specifically, we observed large increases in the levels of endosomal/lysosomal lipids including bis(monoacylglycero)phosphates (BMP) and phosphatidylglycerols (PGs) in ethanol-exposed Mboat7 HSKO mice. In parallel, ethanol-fed Mboat7 HSKO mice exhibited marked dysregulation of autophagic flux and lysosomal biogenesis when exposed to ethanol. This was associated with impaired transcription factor EB (TFEB)-mediated lysosomal biogenesis and accumulation of autophagosomes. Collectively, this works provides new molecular insights into how genetic variation in MBOAT7 impacts ALD progression in humans and mice. This work is the first to causally link MBOAT7 loss of function in hepatocytes, but not myeloid cells, to ethanol-induced liver injury via dysregulation of lysosomal biogenesis and autophagic flux.
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Caddeo A, Spagnuolo R, Maurotti S. MBOAT7 in liver and extrahepatic diseases. Liver Int 2023; 43:2351-2364. [PMID: 37605540 DOI: 10.1111/liv.15706] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 07/28/2023] [Accepted: 08/10/2023] [Indexed: 08/23/2023]
Abstract
MBOAT7 is a protein anchored to endomembranes by several transmembrane domains. It has a catalytic dyad involved in remodelling of phosphatidylinositol with polyunsaturated fatty acids. Genetic variants in the MBOAT7 gene have been associated with the entire spectrum of non-alcoholic fatty liver (NAFLD), recently redefined as metabolic dysfunction-associated fatty liver disease (MAFLD) and, lately, steatotic liver disease (SLD), and to an increasing number of extrahepatic conditions. In this review, we will (a) elucidate the molecular mechanisms by which MBOAT7 loss-of-function predisposes to MAFLD and neurodevelopmental disorders and (b) discuss the growing number of genetic studies linking MBOAT7 to hepatic and extrahepatic diseases. MBOAT7 complete loss of function causes severe changes in brain development resulting in several neurological manifestations. Lower MBOAT7 hepatic expression at both the mRNA and protein levels, due to missense nucleotide polymorphisms (SNPs) in the locus containing the MBOAT7 gene, affects specifically metabolic and viral diseases in the liver from simple steatosis to hepatocellular carcinoma, and potentially COVID-19 disease. This body of evidence shows that phosphatidylinositol remodelling is a key factor for human health.
Collapse
Affiliation(s)
- Andrea Caddeo
- Department of Biomedical Sciences, Unit of Oncology and Molecular Pathology, University of Cagliari, Cagliari, Italy
| | - Rocco Spagnuolo
- Department of Health Sciences, University Magna Graecia, Catanzaro, Italy
| | - Samantha Maurotti
- Department of Experimental and Clinical Medicine, Magna Graecia University, Catanzaro, Italy
| |
Collapse
|
12
|
Reinshagen M, Kabisch S, Pfeiffer AF, Spranger J. Liver Fat Scores for Noninvasive Diagnosis and Monitoring of Nonalcoholic Fatty Liver Disease in Epidemiological and Clinical Studies. J Clin Transl Hepatol 2023; 11:1212-1227. [PMID: 37577225 PMCID: PMC10412706 DOI: 10.14218/jcth.2022.00019] [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: 09/15/2022] [Revised: 12/16/2022] [Accepted: 03/21/2023] [Indexed: 07/03/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is strongly associated with the metabolic syndrome and type 2 diabetes and independently contributes to long-term complications. Being often asymptomatic but reversible, it would require population-wide screening, but direct diagnostics are either too invasive (liver biopsy), costly (MRI) or depending on the examiner's expertise (ultrasonography). Hepatosteatosis is usually accommodated by features of the metabolic syndrome (e.g. obesity, disturbances in triglyceride and glucose metabolism), and signs of hepatocellular damage, all of which are reflected by biomarkers, which poorly predict NAFLD as single item, but provide a cheap diagnostic alternative when integrated into composite liver fat indices. Fatty liver index, NAFLD LFS, and hepatic steatosis index are common and accurate indices for NAFLD prediction, but show limited accuracy for liver fat quantification. Other indices are rarely used. Hepatic fibrosis scores are commonly used in clinical practice, but their mandatory reflection of fibrotic reorganization, hepatic injury or systemic sequelae reduces sensitivity for the diagnosis of simple steatosis. Diet-induced liver fat changes are poorly reflected by liver fat indices, depending on the intervention and its specific impact of weight loss on NAFLD. This limited validity in longitudinal settings stimulates research for new equations. Adipokines, hepatokines, markers of cellular integrity, genetic variants but also simple and inexpensive routine parameters might be potential components. Currently, liver fat indices lack precision for NAFLD prediction or monitoring in individual patients, but in large cohorts they may substitute nonexistent imaging data and serve as a compound biomarker of metabolic syndrome and its cardiometabolic sequelae.
Collapse
Affiliation(s)
- Mona Reinshagen
- Department of Endocrinology and Metabolism, Campus Benjamin Franklin, Charité University Medicine, Berlin, Germany
- Deutsches Zentrum für Diabetesforschung e.V., Geschäftsstelle am Helmholtz-Zentrum München, Neuherberg, Germany
| | - Stefan Kabisch
- Department of Endocrinology and Metabolism, Campus Benjamin Franklin, Charité University Medicine, Berlin, Germany
- Deutsches Zentrum für Diabetesforschung e.V., Geschäftsstelle am Helmholtz-Zentrum München, Neuherberg, Germany
| | - Andreas F.H. Pfeiffer
- Department of Endocrinology and Metabolism, Campus Benjamin Franklin, Charité University Medicine, Berlin, Germany
- Deutsches Zentrum für Diabetesforschung e.V., Geschäftsstelle am Helmholtz-Zentrum München, Neuherberg, Germany
| | - Joachim Spranger
- Department of Endocrinology and Metabolism, Campus Benjamin Franklin, Charité University Medicine, Berlin, Germany
- Deutsches Zentrum für Diabetesforschung e.V., Geschäftsstelle am Helmholtz-Zentrum München, Neuherberg, Germany
| |
Collapse
|
13
|
Chen Y, Du X, Kuppa A, Feitosa MF, Bielak LF, O'Connell JR, Musani SK, Guo X, Kahali B, Chen VL, Smith AV, Ryan KA, Eirksdottir G, Allison MA, Bowden DW, Budoff MJ, Carr JJ, Chen YDI, Taylor KD, Oliveri A, Correa A, Crudup BF, Kardia SLR, Mosley TH, Norris JM, Terry JG, Rotter JI, Wagenknecht LE, Halligan BD, Young KA, Hokanson JE, Washko GR, Gudnason V, Province MA, Peyser PA, Palmer ND, Speliotes EK. Genome-wide association meta-analysis identifies 17 loci associated with nonalcoholic fatty liver disease. Nat Genet 2023; 55:1640-1650. [PMID: 37709864 PMCID: PMC10918428 DOI: 10.1038/s41588-023-01497-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 08/07/2023] [Indexed: 09/16/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is common and partially heritable and has no effective treatments. We carried out a genome-wide association study (GWAS) meta-analysis of imaging (n = 66,814) and diagnostic code (3,584 cases versus 621,081 controls) measured NAFLD across diverse ancestries. We identified NAFLD-associated variants at torsin family 1 member B (TOR1B), fat mass and obesity associated (FTO), cordon-bleu WH2 repeat protein like 1 (COBLL1)/growth factor receptor-bound protein 14 (GRB14), insulin receptor (INSR), sterol regulatory element-binding transcription factor 1 (SREBF1) and patatin-like phospholipase domain-containing protein 2 (PNPLA2), as well as validated NAFLD-associated variants at patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily 2 (TM6SF2), apolipoprotein E (APOE), glucokinase regulator (GCKR), tribbles homolog 1 (TRIB1), glycerol-3-phosphate acyltransferase (GPAM), mitochondrial amidoxime-reducing component 1 (MARC1), microsomal triglyceride transfer protein large subunit (MTTP), alcohol dehydrogenase 1B (ADH1B), transmembrane channel like 4 (TMC4)/membrane-bound O-acyltransferase domain containing 7 (MBOAT7) and receptor-type tyrosine-protein phosphatase δ (PTPRD). Implicated genes highlight mitochondrial, cholesterol and de novo lipogenesis as causally contributing to NAFLD predisposition. Phenome-wide association study (PheWAS) analyses suggest at least seven subtypes of NAFLD. Individuals in the top 10% and 1% of genetic risk have a 2.5-fold to 6-fold increased risk of NAFLD, cirrhosis and hepatocellular carcinoma. These genetic variants identify subtypes of NAFLD, improve estimates of disease risk and can guide the development of targeted therapeutics.
Collapse
Affiliation(s)
- Yanhua Chen
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Xiaomeng Du
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Annapurna Kuppa
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Mary F Feitosa
- Division of Statistical Genomics, Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - Lawrence F Bielak
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Jeffrey R O'Connell
- Department of Endocrinology, Diabetes and Nutrition, University of Maryland - Baltimore, Baltimore, MD, USA
| | - Solomon K Musani
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Xiuqing Guo
- The Institute for Translational Genomics and Population Sciences, Department of Pediatrics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Bratati Kahali
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
- Centre for Brain Research, Indian Institute of Science, Bangalore, India
| | - Vincent L Chen
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Albert V Smith
- Department of Biostatistics, University of Michigan, Ann Arbor, MI, USA
| | - Kathleen A Ryan
- Department of Endocrinology, Diabetes and Nutrition, University of Maryland - Baltimore, Baltimore, MD, USA
| | | | - Matthew A Allison
- Department of Family Medicine, University of California San Diego, San Diego, CA, USA
| | - Donald W Bowden
- Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Matthew J Budoff
- Department of Internal Medicine, Lundquist Institute at Harbor-UCLA, Torrance, CA, USA
| | - John Jeffrey Carr
- Department of Radiology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Yii-Der I Chen
- The Institute for Translational Genomics and Population Sciences, Department of Pediatrics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Kent D Taylor
- The Institute for Translational Genomics and Population Sciences, Department of Pediatrics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Antonino Oliveri
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Adolfo Correa
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Breland F Crudup
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Sharon L R Kardia
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Thomas H Mosley
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Jill M Norris
- Department of Epidemiology, Colorado School of Public Health, Aurora, CO, USA
| | - James G Terry
- Department of Radiology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Jerome I Rotter
- The Institute for Translational Genomics and Population Sciences, Department of Pediatrics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Lynne E Wagenknecht
- Division of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Brian D Halligan
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Kendra A Young
- Department of Epidemiology, Colorado School of Public Health, Aurora, CO, USA
| | - John E Hokanson
- Department of Epidemiology, Colorado School of Public Health, Aurora, CO, USA
| | - George R Washko
- Department of Medicine, Division of Pulmonary and Critical Care, Brigham and Women's Hospital, Boston, MA, USA
| | - Vilmundur Gudnason
- Icelandic Heart Association, Kopavogur, Iceland
- Department of Medicine, University of Iceland, Reykjavik, Iceland
| | - Michael A Province
- Division of Statistical Genomics, Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - Patricia A Peyser
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Nicholette D Palmer
- Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Elizabeth K Speliotes
- Department of Internal Medicine, Division of Gastroenterology and Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
14
|
Wang K, Lee CW, Sui X, Kim S, Wang S, Higgs AB, Baublis AJ, Voth GA, Liao M, Walther TC, Farese RV. The structure of phosphatidylinositol remodeling MBOAT7 reveals its catalytic mechanism and enables inhibitor identification. Nat Commun 2023; 14:3533. [PMID: 37316513 PMCID: PMC10267149 DOI: 10.1038/s41467-023-38932-5] [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: 09/23/2022] [Accepted: 05/22/2023] [Indexed: 06/16/2023] Open
Abstract
Cells remodel glycerophospholipid acyl chains via the Lands cycle to adjust membrane properties. Membrane-bound O-acyltransferase (MBOAT) 7 acylates lyso-phosphatidylinositol (lyso-PI) with arachidonyl-CoA. MBOAT7 mutations cause brain developmental disorders, and reduced expression is linked to fatty liver disease. In contrast, increased MBOAT7 expression is linked to hepatocellular and renal cancers. The mechanistic basis of MBOAT7 catalysis and substrate selectivity are unknown. Here, we report the structure and a model for the catalytic mechanism of human MBOAT7. Arachidonyl-CoA and lyso-PI access the catalytic center through a twisted tunnel from the cytosol and lumenal sides, respectively. N-terminal residues on the ER lumenal side determine phospholipid headgroup selectivity: swapping them between MBOATs 1, 5, and 7 converts enzyme specificity for different lyso-phospholipids. Finally, the MBOAT7 structure and virtual screening enabled identification of small-molecule inhibitors that may serve as lead compounds for pharmacologic development.
Collapse
Affiliation(s)
- Kun Wang
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Chia-Wei Lee
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Xuewu Sui
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Biochemistry and Biophysics, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Siyoung Kim
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
| | - Shuhui Wang
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Aidan B Higgs
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Aaron J Baublis
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Harvard T.H. Chan Advanced Multi-Omics Platform, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL, USA
| | - Maofu Liao
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China.
| | - Tobias C Walther
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- Harvard T.H. Chan Advanced Multi-Omics Platform, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Boston, MA, USA.
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Robert V Farese
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| |
Collapse
|
15
|
Bornfeldt KE. Adipocyte phosphatidylinositol biosynthesis via the Lands cycle protects against insulin resistance. J Lipid Res 2023; 64:100383. [PMID: 37127068 PMCID: PMC10239062 DOI: 10.1016/j.jlr.2023.100383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 04/08/2023] [Indexed: 05/03/2023] Open
Affiliation(s)
- Karin E Bornfeldt
- Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, UW Medicine Diabetes Institute and Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA.
| |
Collapse
|
16
|
Sohal A, Chaudhry H, Kowdley KV. Genetic Markers Predisposing to Nonalcoholic Steatohepatitis. Clin Liver Dis 2023; 27:333-352. [PMID: 37024211 DOI: 10.1016/j.cld.2023.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
The growing prevalence of nonalcoholic fatty liver disease (NAFLD) has sparked interest in understanding genetics and epigenetics associated with the development and progression of the disease. A better understanding of the genetic factors related to progression will be beneficial in the risk stratification of patients. These genetic markers can also serve as potential therapeutic targets in the future. In this review, we focus on the genetic markers associated with the progression and severity of NAFLD.
Collapse
Affiliation(s)
- Aalam Sohal
- Liver Institute Northwest, 3216 Northeast 45th Place Suite 212, Seattle, WA 98105, USA
| | - Hunza Chaudhry
- Department of Internal Medicine, UCSF Fresno, 155 North Fresno Street, Fresno, CA 93722, USA
| | - Kris V Kowdley
- Liver Institute Northwest, 3216 Northeast 45th Place Suite 212, Seattle, WA 98105, USA; Elson S. Floyd College of Medicine, Washington State University, WA, USA.
| |
Collapse
|
17
|
Wang Z, Zhu S, Jia Y, Wang Y, Kubota N, Fujiwara N, Gordillo R, Lewis C, Zhu M, Sharma T, Li L, Zeng Q, Lin YH, Hsieh MH, Gopal P, Wang T, Hoare M, Campbell P, Hoshida Y, Zhu H. Positive selection of somatically mutated clones identifies adaptive pathways in metabolic liver disease. Cell 2023; 186:1968-1984.e20. [PMID: 37040760 PMCID: PMC10321862 DOI: 10.1016/j.cell.2023.03.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 12/08/2022] [Accepted: 03/14/2023] [Indexed: 04/13/2023]
Abstract
Somatic mutations in nonmalignant tissues accumulate with age and injury, but whether these mutations are adaptive on the cellular or organismal levels is unclear. To interrogate genes in human metabolic disease, we performed lineage tracing in mice harboring somatic mosaicism subjected to nonalcoholic steatohepatitis (NASH). Proof-of-concept studies with mosaic loss of Mboat7, a membrane lipid acyltransferase, showed that increased steatosis accelerated clonal disappearance. Next, we induced pooled mosaicism in 63 known NASH genes, allowing us to trace mutant clones side by side. This in vivo tracing platform, which we coined MOSAICS, selected for mutations that ameliorate lipotoxicity, including mutant genes identified in human NASH. To prioritize new genes, additional screening of 472 candidates identified 23 somatic perturbations that promoted clonal expansion. In validation studies, liver-wide deletion of Tbx3, Bcl6, or Smyd2 resulted in protection against hepatic steatosis. Selection for clonal fitness in mouse and human livers identifies pathways that regulate metabolic disease.
Collapse
Affiliation(s)
- Zixi Wang
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shijia Zhu
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yuemeng Jia
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yunguan Wang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Naoto Kubota
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Naoto Fujiwara
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ruth Gordillo
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Cheryl Lewis
- Tissue Management Shared Resource, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Min Zhu
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tripti Sharma
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Lin Li
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Qiyu Zeng
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yu-Hsuan Lin
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Meng-Hsiung Hsieh
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Purva Gopal
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tao Wang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Matt Hoare
- University of Cambridge Department of Medicine, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; University of Cambridge Early Cancer Institute, Hutchison Research Centre, Cambridge Biomedical Campus, Cambridge CB2 0XZ, UK
| | - Peter Campbell
- Cancer Genome Project, Wellcome Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
| | - Yujin Hoshida
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hao Zhu
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, Simmons Comprehensive Cancer Center, Children's Research Institute Mouse Genome Engineering Core, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
18
|
Massey WJ, Varadharajan V, Banerjee R, Brown AL, Horak AJ, Hohe RC, Jung BM, Qiu Y, Chan ER, Pan C, Zhang R, Allende DS, Willard B, Cheng F, Lusis AJ, Brown JM. MBOAT7-driven lysophosphatidylinositol acylation in adipocytes contributes to systemic glucose homeostasis. J Lipid Res 2023; 64:100349. [PMID: 36806709 PMCID: PMC10041558 DOI: 10.1016/j.jlr.2023.100349] [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: 07/06/2022] [Revised: 02/08/2023] [Accepted: 02/11/2023] [Indexed: 02/21/2023] Open
Abstract
We previously demonstrated that antisense oligonucleotide-mediated knockdown of Mboat7, the gene encoding membrane bound O-acyltransferase 7, in the liver and adipose tissue of mice promoted high fat diet-induced hepatic steatosis, hyperinsulinemia, and systemic insulin resistance. Thereafter, other groups showed that hepatocyte-specific genetic deletion of Mboat7 promoted striking fatty liver and NAFLD progression in mice but does not alter insulin sensitivity, suggesting the potential for cell autonomous roles. Here, we show that MBOAT7 function in adipocytes contributes to diet-induced metabolic disturbances including hyperinsulinemia and systemic insulin resistance. We generated Mboat7 floxed mice and created hepatocyte- and adipocyte-specific Mboat7 knockout mice using Cre-recombinase mice under the control of the albumin and adiponectin promoter, respectively. Here, we show that MBOAT7 function in adipocytes contributes to diet-induced metabolic disturbances including hyperinsulinemia and systemic insulin resistance. The expression of Mboat7 in white adipose tissue closely correlates with diet-induced obesity across a panel of ∼100 inbred strains of mice fed a high fat/high sucrose diet. Moreover, we found that adipocyte-specific genetic deletion of Mboat7 is sufficient to promote hyperinsulinemia, systemic insulin resistance, and mild fatty liver. Unlike in the liver, where Mboat7 plays a relatively minor role in maintaining arachidonic acid-containing PI pools, Mboat7 is the major source of arachidonic acid-containing PI pools in adipose tissue. Our data demonstrate that MBOAT7 is a critical regulator of adipose tissue PI homeostasis, and adipocyte MBOAT7-driven PI biosynthesis is closely linked to hyperinsulinemia and insulin resistance in mice.
Collapse
Affiliation(s)
- William J Massey
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Venkateshwari Varadharajan
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Rakhee Banerjee
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Amanda L Brown
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Anthony J Horak
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Rachel C Hohe
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Bryan M Jung
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Yunguang Qiu
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - E Ricky Chan
- Institute for Computational Biology, Case Western Reserve University, Cleveland, OH, USA
| | - Calvin Pan
- Departments of Medicine, Microbiology, and Human Genetics, University of California Los Angeles, Los Angeles, CA, USA
| | - Renliang Zhang
- Proteomics and Metabolomics Core, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Daniela S Allende
- Department of Anatomical Pathology, Cleveland Clinic, Cleveland, OH, USA
| | - Belinda Willard
- Proteomics and Metabolomics Core, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Feixiong Cheng
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Aldons J Lusis
- Departments of Medicine, Microbiology, and Human Genetics, University of California Los Angeles, Los Angeles, CA, USA
| | - J Mark Brown
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.
| |
Collapse
|
19
|
Wang Z, Zhu S, Jia Y, Wang Y, Kubota N, Fujiwara N, Gordillo R, Lewis C, Zhu M, Sharma T, Li L, Zeng Q, Lin YH, Hsieh MH, Gopal P, Wang T, Hoare M, Campbell P, Hoshida Y, Zhu H. Positive selection of somatically mutated clones identifies adaptive pathways in metabolic liver disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533505. [PMID: 36993727 PMCID: PMC10055219 DOI: 10.1101/2023.03.20.533505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Somatic mutations in non-malignant tissues accumulate with age and insult, but whether these mutations are adaptive on the cellular or organismal levels is unclear. To interrogate mutations found in human metabolic disease, we performed lineage tracing in mice harboring somatic mosaicism subjected to non-alcoholic steatohepatitis (NASH). Proof-of-concept studies with mosaic loss of Mboat7 , a membrane lipid acyltransferase, showed that increased steatosis accelerated clonal disappearance. Next, we induced pooled mosaicism in 63 known NASH genes, allowing us to trace mutant clones side-by-side. This in vivo tracing platform, which we coined MOSAICS, selected for mutations that ameliorate lipotoxicity, including mutant genes identified in human NASH. To prioritize new genes, additional screening of 472 candidates identified 23 somatic perturbations that promoted clonal expansion. In validation studies, liver-wide deletion of Bcl6, Tbx3, or Smyd2 resulted in protection against NASH. Selection for clonal fitness in mouse and human livers identifies pathways that regulate metabolic disease. Highlights Mosaic Mboat7 mutations that increase lipotoxicity lead to clonal disappearance in NASH. In vivo screening can identify genes that alter hepatocyte fitness in NASH. Mosaic Gpam mutations are positively selected due to reduced lipogenesis. In vivo screening of transcription factors and epifactors identified new therapeutic targets in NASH.
Collapse
|
20
|
Sharpe MC, Pyles KD, Hallcox T, Kamm DR, Piechowski M, Fisk B, Albert CJ, Carpenter DH, Ulmasov B, Ford DA, Neuschwander-Tetri BA, McCommis KS. Enhancing Hepatic MBOAT7 Expression in Mice With Nonalcoholic Steatohepatitis. GASTRO HEP ADVANCES 2023; 2:558-572. [PMID: 37293574 PMCID: PMC10249591 DOI: 10.1016/j.gastha.2023.02.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND AIMS Polymorphisms near the membrane bound O-acyltransferase domain containing 7 (MBOAT7) genes are associated with worsened nonalcoholic fatty liver (NASH), and nonalcoholic fatty liver disease (NAFLD)/NASH may decrease MBOAT7 expression independent of these polymorphisms. We hypothesized that enhancing MBOAT7 function would improve NASH. METHODS Genomic and lipidomic databases were mined for MBOAT7 expression and hepatic phosphatidylinositol (PI) abundance in human NAFLD/NASH. Male C57BL6/J mice were fed either choline-deficient high-fat diet or Gubra Amylin NASH diet and subsequently infected with adeno-associated virus expressing MBOAT7 or control virus. NASH histological scoring and lipidomic analyses were performed to assess MBOAT7 activity, hepatic PI, and lysophosphatidylinositol (LPI) abundance. RESULTS Human NAFLD/NASH decreases MBOAT7 expression and hepatic abundance of arachidonate-containing PI. Murine NASH models display subtle changes in MBOAT7 expression, but significantly decreased activity. After MBOAT7 overexpression, liver weights, triglycerides, and plasma alanine and aspartate transaminase were modestly improved by MBOAT7 overexpression, but NASH histology was not improved. Despite confirmation of increased activity with MBOAT7 overexpression, content of the main arachidonoylated PI species was not rescued by MBOAT7 although the abundance of many PI species was increased. Free arachidonic acid was elevated but the MBOAT7 substrate arachidonoyl-CoA was decreased in NASH livers compared to low-fat controls, likely due to the decreased expression of long-chain acyl-CoA synthetases. CONCLUSION Results suggest decreased MBOAT7 activity plays a role in NASH, but MBOAT7 overexpression fails to measurably improve NASH pathology potentially due to the insufficient abundance of its arachidonoyl-CoA substrate.
Collapse
Affiliation(s)
- Martin C. Sharpe
- Biochemistry & Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Kelly D. Pyles
- Biochemistry & Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Taylor Hallcox
- Division of Gastroenterology & Hepatology, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Dakota R. Kamm
- Biochemistry & Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Michaela Piechowski
- Biochemistry & Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Bryan Fisk
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri
| | - Carolyn J. Albert
- Biochemistry & Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| | | | - Barbara Ulmasov
- Division of Gastroenterology & Hepatology, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, Missouri
| | - David A. Ford
- Biochemistry & Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Brent A. Neuschwander-Tetri
- Division of Gastroenterology & Hepatology, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Kyle S. McCommis
- Biochemistry & Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| |
Collapse
|
21
|
Afarin R, Aslani F, Asadizade S, Jaberian Asl B, Mohammadi Gahrooie M, Shakerian E, Ahangarpour A. The Effect of Lipopolysaccharide-Stimulated Adipose-Derived Mesenchymal Stem Cells on NAFLD Treatment in High-Fat Diet-Fed Rats. IRANIAN JOURNAL OF PHARMACEUTICAL RESEARCH : IJPR 2023; 22:e134807. [PMID: 38116551 PMCID: PMC10728850 DOI: 10.5812/ijpr-134807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/07/2023] [Accepted: 05/08/2023] [Indexed: 12/21/2023]
Abstract
Background Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are 2 common liver diseases that currently lack effective treatment options. Objectives This study aimed to investigate the effect of lipopolysaccharide (LPS)-stimulated adipose-derived stem cells (ADSCs) on NAFLD treatment in an animal model. Methods Male Wistar rats were fed a high-fat diet (HFD) to induce NAFLD for 7 weeks. The rats were then categorized into 3 groups: Mesenchymal stem cell (MSC), MSC + LPS, and fenofibrate (FENO) groups. Liver and body weight were measured, and the expression of genes involved in fatty acid biosynthesis, β-oxidation, and inflammatory responses was assessed. Results Lipopolysaccharide-stimulated ADSCs were more effective in regulating liver and body weight gain and reducing liver triglyceride (TG) levels compared to the other groups. Treatment with LPS-stimulated ADSCs effectively corrected liver enzymes, including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and lipid factors, including low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) values, better than treatment with both FENO and MSCs. ADSCs + LPS treatment significantly decreased transforming growth factor β (TGF-β) and genes associated with inflammatory responses. Additionally, there was a significant reduction in reactive oxygen species (ROS) levels in the rats treated with ADSCs + LPS. Conclusions Lipopolysaccharide-stimulated ADSCs showed potential in alleviating NAFLD by reducing inflammatory genes and ROS levels in HFD rats, demonstrating better results than treatment with ADSCs and FENO groups alone.
Collapse
Affiliation(s)
- Reza Afarin
- Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Fereshteh Aslani
- Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Shahla Asadizade
- Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Bahar Jaberian Asl
- Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Mehrnoosh Mohammadi Gahrooie
- Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Elham Shakerian
- Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Akram Ahangarpour
- Diabetes Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| |
Collapse
|
22
|
Pansa CC, Molica LR, Moraes KCM. Non-alcoholic fatty liver disease establishment and progression: genetics and epigenetics as relevant modulators of the pathology. Scand J Gastroenterol 2022; 58:521-533. [PMID: 36426638 DOI: 10.1080/00365521.2022.2148835] [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] [Indexed: 11/26/2022]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) results from metabolic dysfunctions that affect more than one-third of the world population. Over the last decades, scientific investigations have clarified many details on the pathology establishment and development; however, effective therapeutics approaches are still evasive. In addition, studies demonstrated that NAFLD establishment and progression are related to several etiologies. Recently, genetics and epigenetics backgrounds have emerged as relevant elements to the pathology onset, and, hence, deserve deep investigation to clarify molecular details on NAFLD signaling, which may be correlated with population behavior. Thus, to minimize the global problem, public health and public policies should take advantage of studies on NAFLD over the next following decades. METHODS In this context, we have performed a selective literature review focusing on biochemistry of lipid metabolism, genetics, epigenetics, and the ethnicity as strong elements that drive NAFLD establishment. RESULTS Considering the etiological agents that acts on NAFLD development and progression, the genetics and the epigenetics emerged as relevant factors. Genetics acts as a powerful element in the establishment and progression of the NAFLD. Over the last decades, details concerning genes and their polymorphisms, as well as epigenetics, have been considered relevant elements in the systems biology of diseases, and their effects on NAFLD should be considered in-depth, as well as the ethnicity, clarifying whether people are susceptible to liver diseases. Moreover, the endemicity and social problems of hepatic disfunction are far to be solved, which require a combined effort of various sectors of society. CONCLUSION Hence, the elements presented and discussed in this short review demonstrated their relevance to the physiological control of NAFLD, opening perspectives for research to develop new strategy to treat fatty liver diseases.
Collapse
Affiliation(s)
- Camila Cristiane Pansa
- Departamento de Biologia Geral e Aplicada, Cellular Signalling and Gene Expression Laboratory, Universidade Estadual Paulista "Júlio de Mesquita Filho", Instituto de Biociências, Rio Claro, Brazil
| | - Letícia Ramos Molica
- Departamento de Biologia Geral e Aplicada, Cellular Signalling and Gene Expression Laboratory, Universidade Estadual Paulista "Júlio de Mesquita Filho", Instituto de Biociências, Rio Claro, Brazil
| | - Karen C M Moraes
- Departamento de Biologia Geral e Aplicada, Cellular Signalling and Gene Expression Laboratory, Universidade Estadual Paulista "Júlio de Mesquita Filho", Instituto de Biociências, Rio Claro, Brazil
| |
Collapse
|
23
|
Sveinbjornsson G, Ulfarsson MO, Thorolfsdottir RB, Jonsson BA, Einarsson E, Gunnlaugsson G, Rognvaldsson S, Arnar DO, Baldvinsson M, Bjarnason RG, Eiriksdottir T, Erikstrup C, Ferkingstad E, Halldorsson GH, Helgason H, Helgadottir A, Hindhede L, Hjorleifsson G, Jones D, Knowlton KU, Lund SH, Melsted P, Norland K, Olafsson I, Olafsson S, Oskarsson GR, Ostrowski SR, Pedersen OB, Snaebjarnarson AS, Sigurdsson E, Steinthorsdottir V, Schwinn M, Thorgeirsson G, Thorleifsson G, Jonsdottir I, Bundgaard H, Nadauld L, Bjornsson ES, Rulifson IC, Rafnar T, Norddahl GL, Thorsteinsdottir U, Sulem P, Gudbjartsson DF, Holm H, Stefansson K. Multiomics study of nonalcoholic fatty liver disease. Nat Genet 2022; 54:1652-1663. [PMID: 36280732 PMCID: PMC9649432 DOI: 10.1038/s41588-022-01199-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 09/02/2022] [Indexed: 11/09/2022]
Abstract
Nonalcoholic fatty liver (NAFL) and its sequelae are growing health problems. We performed a genome-wide association study of NAFL, cirrhosis and hepatocellular carcinoma, and integrated the findings with expression and proteomic data. For NAFL, we utilized 9,491 clinical cases and proton density fat fraction extracted from 36,116 liver magnetic resonance images. We identified 18 sequence variants associated with NAFL and 4 with cirrhosis, and found rare, protective, predicted loss-of-function variants in MTARC1 and GPAM, underscoring them as potential drug targets. We leveraged messenger RNA expression, splicing and predicted coding effects to identify 16 putative causal genes, of which many are implicated in lipid metabolism. We analyzed levels of 4,907 plasma proteins in 35,559 Icelanders and 1,459 proteins in 47,151 UK Biobank participants, identifying multiple proteins involved in disease pathogenesis. We show that proteomics can discriminate between NAFL and cirrhosis. The present study provides insights into the development of noninvasive evaluation of NAFL and new therapeutic options.
Collapse
Affiliation(s)
| | - Magnus O Ulfarsson
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland.,Faculty of Electrical and Computer Engineering, University of Iceland, Reykjavik, Iceland
| | | | | | | | | | | | - David O Arnar
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, Reykjavik, Iceland.,Internal Medicine and Emergency Services, Landspitali-The National University Hospital of Iceland, Reykjavik, Iceland
| | | | - Ragnar G Bjarnason
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland.,Children's Medical Center, Landspítali-The National University Hospital of Iceland, Reykjavík, Iceland
| | | | | | - Christian Erikstrup
- Department of Clinical Immunology, Aarhus University Hospital, Aarhus, Denmark
| | | | | | | | | | - Lotte Hindhede
- Department of Clinical Immunology, Aarhus University Hospital, Aarhus, Denmark
| | | | - David Jones
- Intermountain Healthcare, St. George, UT, USA
| | | | | | - Pall Melsted
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland.,Faculty of Mechanical Engineering, Industrial Engineering and Computer Science, University of Iceland, Reykjavik, Iceland
| | | | - Isleifur Olafsson
- Clinical Laboratory Services, Diagnostics and Blood Bank, Landspitali-The National University Hospital of Iceland, Reykjavik, Iceland
| | - Sigurdur Olafsson
- Internal Medicine and Emergency Services, Landspitali-The National University Hospital of Iceland, Reykjavik, Iceland
| | | | - Sisse Rye Ostrowski
- Department of Clinical Immunology, Copenhagen University Hospital, Rigshospitalet, Cophenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Ole Birger Pedersen
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Immunology, Zealand University Hospital, Køge, Denmark
| | | | - Emil Sigurdsson
- Development Centre for Primary Health Care in Iceland, Reykjavík, Iceland.,Department of Family Medicine, University of Iceland, Reykjavik, Iceland
| | | | - Michael Schwinn
- Department of Clinical Immunology, Copenhagen University Hospital, Rigshospitalet, Cophenhagen, Denmark
| | - Gudmundur Thorgeirsson
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland.,Internal Medicine and Emergency Services, Landspitali-The National University Hospital of Iceland, Reykjavik, Iceland
| | | | - Ingileif Jonsdottir
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - Henning Bundgaard
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.,Department of Cardiology, The Heart Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | | | - Einar S Bjornsson
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland.,Internal Medicine and Emergency Services, Landspitali-The National University Hospital of Iceland, Reykjavik, Iceland
| | | | | | | | - Unnur Thorsteinsdottir
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | | | - Daniel F Gudbjartsson
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland.,Faculty of Electrical and Computer Engineering, University of Iceland, Reykjavik, Iceland.,School of Engineering and Natural Sciences, University of Iceland, Reykjavik, Iceland
| | - Hilma Holm
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland
| | - Kari Stefansson
- deCODE genetics/Amgen, Inc., Reykjavik, Iceland. .,Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
| |
Collapse
|
24
|
Busca C, Arias P, Sánchez-Conde M, Rico M, Montejano R, Martín-Carbonero L, Valencia E, Moreno V, Bernardino JI, Olveira A, Abadía M, González-García J, Montes ML. Genetic variants associated with steatohepatitis and liver fibrosis in HIV-infected patients with NAFLD. Front Pharmacol 2022; 13:905126. [PMID: 36110512 PMCID: PMC9468702 DOI: 10.3389/fphar.2022.905126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 07/08/2022] [Indexed: 12/04/2022] Open
Abstract
Background and aims: Nonalcoholic fatty liver disease (NAFLD) is a common cause of liver damage in people living with HIV (PLWHIV). Several studies have investigated candidate genes for susceptibility to NAFLD and to steatohepatitis. PNPLA3, TM6SF2, and MBOAT7-TMC4 have been reported to be associated with elevated ALT levels and the histologic parameters of nonalcoholic steatohepatitis and severity of fibrosis. Our objective was to analyze the relationship between PNPLA3, TM6SF2, and MBOAT7-TMC4 and steatosis, steatohepatitis, and liver fibrosis in PLWHIV with NAFLD. Method: A cohort of PLWHIV with persistently elevated aminotransferase levels and suspected NAFLD who underwent liver biopsy and determination of genetic variants was assessed at two large centers in Spain. All participants included in the current study were genotyped for rs738409 (PNPLA3), rs58542926 (TM6SF2), and rs641738 (MBOAT7-TMC4). Results: The study population comprised PLWHIV who were on stable antiretroviral therapy [7.7% women; median age, 49.3 years (44-53.4)]. The median CD4 count was 829 (650-980), 60% had metabolic syndrome, and 18.5% were diabetic. The median BMI was 28.9 (25.5-30.8). Patients with liver steatosis (any grade) vs. nonsteatosis tended to harbor the PNPLA3 G allele variant [57.6% vs. 16.7% (p = 0.09)], but not TM6SF2 or MBOAT7-TMC4 variants. However, those with steatohepatitis vs. nonsteatohepatitis significantly more frequently had the PNPLA3 G allele variant [69.4% vs. 39.1% (p < 0.05)] and the MBOAT7-TMC4 A allele variant [75% vs. 42% (p < 0.05)]. In our cohort, the TM6SF2 gene variant was not associated with steatosis or steatohepatitis. The PNPLA3 G allele variant was associated with steatohepatitis [OR 4.9 (1.3-18); p 0.02] and liver fibrosis [OR 4.3 (1.1-17.4); p 0.04], and the MBOAT7-TMC4 A allele variant was associated with steatohepatitis [OR 6.6 (1.6-27.6); p 0.01]. Conclusion: The PNPLA3 G allele variant and MBOAT7-TMC4 A allele variant were associated with steatohepatitis and liver fibrosis in PLWHIV with persistently elevated aminotransferases and NAFLD. We recommend routine genotyping for PNPLA3 and MBOAT7-TMC4 in PLWHIV with NAFLD to identify those at higher risk of progression.
Collapse
Affiliation(s)
- C. Busca
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - P. Arias
- Instituto de Genética Médica y Molecular (INGEMM), IdiPaz, Hospital Universitario La Paz, Madrid, Spain
| | - M. Sánchez-Conde
- Infectious Diseases Department, Hospital Universitario Ramón y Cajal, Madrid, Spain
| | - M. Rico
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - R. Montejano
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - L. Martín-Carbonero
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - E. Valencia
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - V. Moreno
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - J. I. Bernardino
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - A. Olveira
- Gastroenterology, Hospital La Paz, Madrid, Spain
| | - M. Abadía
- Gastroenterology, Hospital La Paz, Madrid, Spain
| | - J. González-García
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| | - M. L. Montes
- Unidad VIH, Servicio Medicina Interna, IdiPAz, Hospital Universitario La Paz, Madrid, Spain
| |
Collapse
|
25
|
Jain R, Wade G, Ong I, Chaurasia B, Simcox J. Determination of tissue contributions to the circulating lipid pool in cold exposure via systematic assessment of lipid profiles. J Lipid Res 2022; 63:100197. [PMID: 35300982 PMCID: PMC9234243 DOI: 10.1016/j.jlr.2022.100197] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/21/2022] [Accepted: 02/27/2022] [Indexed: 01/07/2023] Open
Abstract
Plasma lipid levels are altered in chronic conditions such as type 2 diabetes and cardiovascular disease as well as during acute stresses such as fasting and cold exposure. Advances in MS-based lipidomics have uncovered a complex plasma lipidome of more than 500 lipids that serve functional roles, including as energy substrates and signaling molecules. This plasma lipid pool is maintained through regulation of tissue production, secretion, and uptake. A major challenge in understanding the lipidome complexity is establishing the tissues of origin and uptake for various plasma lipids, which is valuable for determining lipid functions. Using cold exposure as an acute stress, we performed global lipidomics on plasma and in nine tissues that may contribute to the circulating lipid pool. We found that numerous species of plasma acylcarnitines (ACars) and ceramides (Cers) were significantly altered upon cold exposure. Through computational assessment, we identified the liver and brown adipose tissue as major contributors and consumers of circulating ACars, in agreement with our previous work. We further identified the kidney and intestine as novel contributors to the circulating ACar pool and validated these findings with gene expression analysis. Regression analysis also identified that the brown adipose tissue and kidney are interactors with the plasma Cer pool. Taken together, these studies provide an adaptable computational tool to assess tissue contribution to the plasma lipid pool. Our findings have further implications in understanding the function of plasma ACars and Cers, which are elevated in metabolic diseases.
Collapse
Affiliation(s)
- Raghav Jain
- Department of Biochemistry, University of Wisconsin-Madison, Wisconsin, USA
| | - Gina Wade
- Department of Biochemistry, University of Wisconsin-Madison, Wisconsin, USA
| | - Irene Ong
- Department of Biostatistics and Medical Informatics, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Wisconsin, USA
| | - Bhagirath Chaurasia
- Division of Endocrinology, Department of Internal Medicine, Carver College of Medicine, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa, USA
| | - Judith Simcox
- Department of Biochemistry, University of Wisconsin-Madison, Wisconsin, USA.
| |
Collapse
|
26
|
Varadharajan V, Massey WJ, Brown JM. Membrane-bound O-acyltransferase 7 (MBOAT7)-driven phosphatidylinositol remodeling in advanced liver disease. J Lipid Res 2022; 63:100234. [PMID: 35636492 PMCID: PMC9240865 DOI: 10.1016/j.jlr.2022.100234] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/12/2022] [Accepted: 05/16/2022] [Indexed: 01/21/2023] Open
Abstract
Advanced liver diseases account for approximately 2 million deaths annually worldwide. Roughly, half of liver disease-associated deaths arise from complications of cirrhosis and the other half driven by viral hepatitis and hepatocellular carcinoma. Unfortunately, the development of therapeutic strategies to treat subjects with advanced liver disease has been hampered by a lack of mechanistic understanding of liver disease progression and a lack of human-relevant animal models. An important advance has been made within the past several years, as several genome-wide association studies have discovered that an SNP near the gene encoding membrane-bound O-acyltransferase 7 (MBOAT7) is associated with severe liver diseases. This common MBOAT7 variant (rs641738, C>T), which reduces MBOAT7 expression, confers increased susceptibility to nonalcoholic fatty liver disease, alcohol-associated liver disease, and liver fibrosis in patients chronically infected with viral hepatitis. Recent studies in mice also show that Mboat7 loss of function can promote hepatic steatosis, inflammation, and fibrosis, causally linking this phosphatidylinositol remodeling enzyme to liver health in both rodents and humans. Herein, we review recent insights into the mechanisms by which MBOAT7-driven phosphatidylinositol remodeling influences liver disease progression and discuss how rapid progress in this area could inform drug discovery moving forward.
Collapse
Affiliation(s)
- Venkateshwari Varadharajan
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - William J Massey
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - J Mark Brown
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute Cleveland Clinic, Cleveland, OH, USA; Center for Microbiome and Human Health, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.
| |
Collapse
|
27
|
Xia M, Ma S, Huang Q, Zeng H, Ge J, Xu W, Wu Q, Wu L, Li X, Ma H, Chen L, Li Q, Aleteng Q, Hu Y, He W, Pan B, Lin H, Zheng Y, Wang S, Tang H, Gao X. NAFLD-related gene polymorphisms and all-cause and cause-specific mortality in an Asian population: the Shanghai Changfeng Study. Aliment Pharmacol Ther 2022; 55:705-721. [PMID: 35023183 DOI: 10.1111/apt.16772] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 12/13/2021] [Accepted: 12/31/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND The PNPLA3 and TM6SF2 gene variants have been found to cause NAFLD with a favourable cardiovascular risk profile. AIMS To investigate the effects of the NAFLD risk alleles on the all-cause and cause-specific mortality in 5581 Chinese adults. METHODS The genome-wide genotypes were detected using a genotyping array and serum lipoprotein profiles were examined using 1H NMR platform. Liver fat content (LFC) was measured using a quantitative ultrasound method. The vital status was determined using official registration data. RESULTS Genome-wide association analysis showed that a series of variants in PNPLA3 were associated with LFC, including rs738409 C>G variant (P = 8.6 × 10-7 ). Further analyses validated the associations of TM6SF2 rs58542926 C>T and MBOAT7 rs641738 C>T variants with NAFLD. During 29 425.1 person-years of follow-up, the overall mortality was 816 per 100 000 person-years, where 299 deaths were attributable to cardiovascular disease and 85 to liver disease. The PNPLA3 rs738409 C>G variant was independently associated with increased liver-specific mortality (P for trend = 0.034) but reduced cardiovascular mortality (P for trend = 0.047). A composite genetic-predisposition score of PNPLA3, TM6SF2, and MBOAT7 risk alleles presented similar opposite effects on liver-specific and cardiovascular mortality. Moreover, interactions of the NAFLD risk alleles with adiposity for liver-specific mortality were found (Pinteraction < 0.05). The reduced serum VLDL1 concentration was responsible for the increased liver-specific mortality related to NAFLD risk alleles. CONCLUSION The PNPLA3 rs738409 C>G variant and its combination with TM6SF2 rs58542926 C>T and MBOAT7 rs641738 C>T variants increase liver-specific mortality but reduce cardiovascular mortality in overweight/obese Chinese.
Collapse
Affiliation(s)
- Mingfeng Xia
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Shuai Ma
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Qingxia Huang
- State Key Laboratory of Genetic Engineering, Zhongshan Hospital and School of Life Sciences, Human Phenome Institute, Metabonomics and Systems Biology Laboratory at Shanghai International Centre for Molecular Phenomics, Fudan University, Shanghai, China
| | - Hailuan Zeng
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Jieyu Ge
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, Shanghai, China
| | - Wenjie Xu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Qi Wu
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Li Wu
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Xiaoming Li
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Hui Ma
- Department of Geriatrics, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Lingyan Chen
- Department of Geriatrics, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qian Li
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Qiqige Aleteng
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Yu Hu
- Department of Geriatrics, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Wanyuan He
- Department of Ultrasonography, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Baishen Pan
- Department of Laboratory Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Huandong Lin
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | - Yan Zheng
- Department of Cardiology Zhongshan Hospital, State Key Laboratory of Genetic Engineering School of Life Sciences, Human Phenome Institute, Fudan University, Shanghai, China
| | - Sijia Wang
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, Shanghai, China
| | - Huiru Tang
- State Key Laboratory of Genetic Engineering, Zhongshan Hospital and School of Life Sciences, Human Phenome Institute, Metabonomics and Systems Biology Laboratory at Shanghai International Centre for Molecular Phenomics, Fudan University, Shanghai, China
| | - Xin Gao
- Department of Endocrinology and Metabolism, Zhongshan Hospital and Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| |
Collapse
|
28
|
Zhu X, Xia M, Gao X. Update on genetics and epigenetics in metabolic associated fatty liver disease. Ther Adv Endocrinol Metab 2022; 13:20420188221132138. [PMID: 36325500 PMCID: PMC9619279 DOI: 10.1177/20420188221132138] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/25/2022] [Indexed: 11/06/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is becoming the most frequent chronic liver disease worldwide. Metabolic (dysfunction) associated fatty liver disease (MAFLD) is suggested to replace the nomenclature of NAFLD. For individuals with metabolic dysfunction, multiple NAFLD-related factors also contribute to the development and progression of MAFLD including genetics and epigenetics. The application of genome-wide association study (GWAS) and exome-wide association study (EWAS) uncovers single-nucleotide polymorphisms (SNPs) in MAFLD. In addition to the classic SNPs in PNPLA3, TM6SF2, and GCKR, some new SNPs have been found recently to contribute to the pathogenesis of liver steatosis. Epigenetic factors involving DNA methylation, histone modifications, non-coding RNAs regulations, and RNA methylation also play a critical role in MAFLD. DNA methylation is the most reported epigenetic modification. Developing a non-invasion biomarker to distinguish metabolic steatohepatitis (MASH) or liver fibrosis is ongoing. In this review, we summarized and discussed the latest progress in genetic and epigenetic factors of NAFLD/MAFLD, in order to provide potential clues for MAFLD treatment.
Collapse
Affiliation(s)
- Xiaopeng Zhu
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | | | - Xin Gao
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| |
Collapse
|
29
|
Luo F, Smagris E, Martin SA, Vale G, McDonald JG, Fletcher JA, Burgess SC, Hobbs HH, Cohen JC. Hepatic TM6SF2 Is Required for Lipidation of VLDL in a Pre-Golgi Compartment in Mice and Rats. Cell Mol Gastroenterol Hepatol 2021; 13:879-899. [PMID: 34923175 PMCID: PMC8804273 DOI: 10.1016/j.jcmgh.2021.12.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Substitution of lysine for glutamic acid at residu 167 in Transmembrane 6 superfamily member 2 (TM6SF2) is associated with fatty liver disease and reduced plasma lipid levels. Tm6sf2-/- mice replicate the human phenotype but were not suitable for detailed mechanistic studies. As an alternative model, we generated Tm6sf2-/- rats to determine the subcellular location and function of TM6SF2. METHODS Two lines of Tm6sf2-/- rats were established using gene editing. Lipids from tissues and from newly secreted very low density lipoproteins (VLDLs) were quantified using enzymatic assays and mass spectrometry. Neutral lipids were visualized in tissue sections using Oil Red O staining. The rate of dietary triglyceride (TG) absorption and hepatic VLDL-TG secretion were compared in Tm6sf2-/- mice and in their wild-type littermates. The intracellular location of TM6SF2 was determined by cell fractionation. Finally, TM6SF2 was immunoprecipitated from liver and enterocytes to identify interacting proteins. RESULTS Tm6sf2-/- rats had a 6-fold higher mean hepatic TG content (56.1 ± 28.9 9 vs 9.8 ± 3.9 mg/g; P < .0001) and lower plasma cholesterol levels (99.0 ± 10.5 vs 110.6 ± 14.0 mg/dL; P = .0294) than their wild-type littermates. Rates of appearance of dietary and hepatic TG into blood were reduced significantly in Tm6sf2-/- rats (P < .001 and P < .01, respectively). Lipid content of newly secreted VLDLs isolated from perfused livers was reduced by 53% (TG) and 62% (cholesterol) (P = .005 and P = .01, respectively) in Tm6sf2-/- mice. TM6SF2 was present predominantly in the smooth endoplasmic reticulum and endoplasmic reticulum-Golgi intermediate compartments, but not in Golgi. Both apolipoprotein B-48 and acyl-CoA synthetase long chain family member 5 physically interacted with TM6SF2. CONCLUSIONS TM6SF2 acts in the smooth endoplasmic reticulum to promote bulk lipidation of apolipoprotein B-containing lipoproteins, thus preventing fatty liver disease.
Collapse
Affiliation(s)
- Fei Luo
- Department of Molecular Genetics, Dallas, Texas,Department of Cardiovascular Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | | | | | - Goncalo Vale
- Department of Molecular Genetics, Dallas, Texas,Center for Human Nutrition, Dallas, Texas
| | - Jeffrey G. McDonald
- Department of Molecular Genetics, Dallas, Texas,Center for Human Nutrition, Dallas, Texas
| | | | | | - Helen H. Hobbs
- Department of Molecular Genetics, Dallas, Texas,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas,Correspondence Address correspondence to: Helen H. Hobbs, MD, or Jonathan C. Cohen, PhD, Department of Molecular Genetics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 07390-9046.fax: (214) 648-7539.
| | - Jonathan C. Cohen
- Center for Human Nutrition, Dallas, Texas,Correspondence Address correspondence to: Helen H. Hobbs, MD, or Jonathan C. Cohen, PhD, Department of Molecular Genetics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 07390-9046.fax: (214) 648-7539.
| |
Collapse
|
30
|
Valentine WJ, Yanagida K, Kawana H, Kono N, Noda NN, Aoki J, Shindou H. Update and nomenclature proposal for mammalian lysophospholipid acyltransferases which create membrane phospholipid diversity. J Biol Chem 2021; 298:101470. [PMID: 34890643 PMCID: PMC8753187 DOI: 10.1016/j.jbc.2021.101470] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/13/2022] Open
Abstract
The diversity of glycerophospholipid species in cellular membranes is immense and affects various biological functions. Glycerol-3-phosphate acyltransferases (GPATs) and lysophospholipid acyltransferases (LPLATs), in concert with phospholipase A1/2s enzymes, contribute to this diversity via selective esterification of fatty acyl chains at the sn-1 or sn-2 positions of membrane phospholipids. These enzymes are conserved across all kingdoms, and in mammals four GPATs of the 1-acylglycerol-3-phosphate O-acyltransferase (AGPAT) family and at least 14 LPLATs, either of the AGPAT or the membrane-bound O-acyltransferase (MBOAT) families, have been identified. Here we provide an overview of the biochemical and biological activities of these mammalian enzymes, including their predicted structures, involvements in human diseases, and essential physiological roles as revealed by gene-deficient mice. Recently, the nomenclature used to refer to these enzymes has generated some confusion due to the use of multiple names to refer to the same enzyme and instances of the same name being used to refer to completely different enzymes. Thus, this review proposes a more uniform LPLAT enzyme nomenclature, as well as providing an update of recent advances made in the study of LPLATs, continuing from our JBC mini review in 2009.
Collapse
Affiliation(s)
- William J Valentine
- Department of Lipid Signaling, National Center for Global Health and Medicine (NCGM), Shinjuku-ku, Tokyo 162-8655, Japan; Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, 187-8502, Japan
| | - Keisuke Yanagida
- Department of Lipid Signaling, National Center for Global Health and Medicine (NCGM), Shinjuku-ku, Tokyo 162-8655, Japan
| | - Hiroki Kawana
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Nobuo N Noda
- Institute of Microbial Chemistry (BIKAKEN), Microbial Chemistry Research Foundation, Tokyo 141-0021, Japan
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hideo Shindou
- Department of Lipid Signaling, National Center for Global Health and Medicine (NCGM), Shinjuku-ku, Tokyo 162-8655, Japan; Department of Lipid Medical Science, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
| |
Collapse
|
31
|
Chen S, Che S, Li S, Ruan Z. The combined impact of decabromodiphenyl ether and high fat exposure on non-alcoholic fatty liver disease in vivo and in vitro. Toxicology 2021; 464:153015. [PMID: 34757160 DOI: 10.1016/j.tox.2021.153015] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 12/22/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is considered a public health concern. Decabromodiphenyl ether (BDE-209) and high fat (HF) exposure cause liver injury, yet the combined impact on NAFLD development remains unclear. HepG2 cells were incubated with BDE-209 or/and HF reagent (Csodium oleate/Csodium palmitate = 2/1) for establishing the in vitro model, while C57BL/6 mice fed BDE-209 or/and HF diet (HFD) was the in vivo model. Oil Red O staining and the determination of triglyceride, malondialdehyde, and reactive oxygen species (ROS) contents proved the elevated lipid accumulation and oxidative stress by the mixture of BDE-209 and HF in HepG2 cells, consistent in C57BL/6 mice. Importantly, the action analysis showed the synergistic effect between BDE-209 and HF, suggesting that the population preferring the HFD is more susceptible to BDE-209 to aggravate the progression of NAFLD. Further, the increased protein expression of sterol regulatory element-binding protein 1, fatty acid synthase, and stearoyl-CoA desaturase 1 was considered to be responsible for hepatic steatosis. The impairment of antioxidant system was reflected by the lower hepatic superoxide dismutase and glutathione transferase activities and reduced glutathione level, explaining the detected excessive ROS production. Besides, using high content analysis, the decline of mitochondrial mass and membrane potential, which was closed to the NAFLD pathogenesis, was also demonstrated in HepG2 cells.
Collapse
Affiliation(s)
- Sunni Chen
- State Key Laboratory of Food Science and Technology, Nanchang Key Laboratory of Fruits and Vegetables Nutrition and Processing, Institute of Nutrition and School of Food Science, Nanchang University, Nanchang, 330047, China
| | - Siyan Che
- State Key Laboratory of Food Science and Technology, Nanchang Key Laboratory of Fruits and Vegetables Nutrition and Processing, Institute of Nutrition and School of Food Science, Nanchang University, Nanchang, 330047, China
| | - Shiqi Li
- State Key Laboratory of Food Science and Technology, Nanchang Key Laboratory of Fruits and Vegetables Nutrition and Processing, Institute of Nutrition and School of Food Science, Nanchang University, Nanchang, 330047, China
| | - Zheng Ruan
- State Key Laboratory of Food Science and Technology, Nanchang Key Laboratory of Fruits and Vegetables Nutrition and Processing, Institute of Nutrition and School of Food Science, Nanchang University, Nanchang, 330047, China.
| |
Collapse
|
32
|
SREBP-1c and lipogenesis in the liver: an update1. Biochem J 2021; 478:3723-3739. [PMID: 34673919 DOI: 10.1042/bcj20210071] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/28/2021] [Accepted: 09/30/2021] [Indexed: 12/13/2022]
Abstract
Sterol Regulatory Element Binding Protein-1c is a transcription factor that controls the synthesis of lipids from glucose in the liver, a process which is of utmost importance for the storage of energy. Discovered in the early nineties by B. Spiegelman and by M. Brown and J. Goldstein, it has generated more than 5000 studies in order to elucidate its mechanism of activation and its role in physiology and pathology. Synthetized as a precursor found in the membranes of the endoplasmic reticulum, it has to be exported to the Golgi and cleaved by a mechanism called regulated intramembrane proteolysis. We reviewed in 2002 its main characteristics, its activation process and its role in the regulation of hepatic glycolytic and lipogenic genes. We particularly emphasized that Sterol Regulatory Element Binding Protein-1c is the mediator of insulin effects on these genes. In the present review, we would like to update these informations and focus on the response to insulin and to another actor in Sterol Regulatory Element Binding Protein-1c activation, the endoplasmic reticulum stress.
Collapse
|
33
|
Meroni M, Longo M, Tria G, Dongiovanni P. Genetics Is of the Essence to Face NAFLD. Biomedicines 2021; 9:1359. [PMID: 34680476 PMCID: PMC8533437 DOI: 10.3390/biomedicines9101359] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 09/27/2021] [Indexed: 02/07/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the commonest cause of chronic liver disease worldwide. It is closely related to obesity, insulin resistance (IR) and dyslipidemia so much so it is considered the hepatic manifestation of the Metabolic Syndrome. The NAFLD spectrum extends from simple steatosis to nonalcoholic steatohepatitis (NASH), a clinical condition which may progress up to fibrosis, cirrhosis and hepatocellular carcinoma (HCC). NAFLD is a complex disease whose pathogenesis is shaped by both environmental and genetic factors. In the last two decades, several heritable modifications in genes influencing hepatic lipid remodeling, and mitochondrial oxidative status have been emerged as predictors of progressive hepatic damage. Among them, the patatin-like phospholipase domain-containing 3 (PNPLA3) p.I148M, the Transmembrane 6 superfamily member 2 (TM6SF2) p.E167K and the rs641738 membrane bound-o-acyltransferase domain-containing 7 (MBOAT7) polymorphisms are considered the most robust modifiers of NAFLD. However, a forefront frontier in the study of NAFLD heritability is to postulate score-based strategy, building polygenic risk scores (PRS), which aggregate the most relevant genetic determinants of NAFLD and biochemical parameters, with the purpose to foresee patients with greater risk of severe NAFLD, guaranteeing the most highly predictive value, the best diagnostic accuracy and the more precise individualized therapy.
Collapse
Affiliation(s)
- Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
| | - Miriam Longo
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
- Department of Clinical Sciences and Community Health, Università Degli Studi di Milano, 20122 Milano, Italy
| | - Giada Tria
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
| |
Collapse
|
34
|
Measurement of lipogenic flux by deuterium resolved mass spectrometry. Nat Commun 2021; 12:3756. [PMID: 34145255 PMCID: PMC8213799 DOI: 10.1038/s41467-021-23958-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 05/25/2021] [Indexed: 01/09/2023] Open
Abstract
De novo lipogenesis (DNL) is disrupted in a wide range of human disease. Thus, quantification of DNL may provide insight into mechanisms and guide interventions if it can be performed rapidly and noninvasively. DNL flux is commonly measured by 2H incorporation into fatty acids following deuterated water (2H2O) administration. However, the sensitivity of this approach is limited by the natural abundance of 13C, which masks detection of 2H by mass spectrometry. Here we report that high-resolution Orbitrap gas-chromatography mass-spectrometry resolves 2H and 13C fatty acid mass isotopomers, allowing DNL to be quantified using lower 2H2O doses and shorter experimental periods than previously possible. Serial measurements over 24-hrs in mice detects the nocturnal activation of DNL and matches a 3H-water method in mice with genetic activation of DNL. Most importantly, DNL is detected in overnight-fasted humans in less than an hour and is responsive to feeding during a 4-h study. Thus, 2H specific MS provides the ability to study DNL in settings that are currently impractical.
Collapse
|
35
|
Abstract
PURPOSE OF REVIEW Nonalcoholic fatty liver disease (NAFLD) is defined as the abnormal accumulation of lipids in the liver, called hepatic steatosis, which occurs most often as a concomitant of the metabolic syndrome. Its incidence has surged significantly in recent decades concomitant with the obesity pandemic and increasing consumption of refined carbohydrates and saturated fats. This makes a review of the origins of NAFLD timely and relevant. RECENT FINDINGS This disorder, which shares histologic markers found in alcoholic fatty liver disease, was named NAFLD to distinguish it from the latter. Recently, however, the term metabolic-associated fatty liver disease (MAFLD) has been suggested as a refinement of NAFLD that should highlight the central, etiologic role of insulin resistance, obesity, and diabetes mellitus. The complexity of the pathways involved in the regulation of hepatic triglyceride synthesis and utilization have become obvious over the past 10 years, including the recent identification of monogenic causes of metabolic-associated fatty liver disease. These include PNPLA3, transmembrane 6 superfamily member 2, GCKR, membrane-bound O-acyltransferase 7 suggest targets for new therapies for hepatic steatosis. SUMMARY The current review can serve as a guide to the complex pathways involved in the maintenance of hepatic triglyceride levels as well as an introduction to the most recent discoveries, including those of key genes that have provided opportunities for new and novel therapeutics.
Collapse
Affiliation(s)
- Leinys S Santos-Baez
- Division of Preventive Medicine and Nutrition, Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | | |
Collapse
|
36
|
Bianco C, Casirati E, Malvestiti F, Valenti L. Genetic predisposition similarities between NASH and ASH: Identification of new therapeutic targets. JHEP Rep 2021; 3:100284. [PMID: 34027340 PMCID: PMC8122117 DOI: 10.1016/j.jhepr.2021.100284] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/09/2021] [Accepted: 03/15/2021] [Indexed: 12/12/2022] Open
Abstract
Fatty liver disease can be triggered by a combination of excess alcohol, dysmetabolism and other environmental cues, which can lead to steatohepatitis and can evolve to acute/chronic liver failure and hepatocellular carcinoma, especially in the presence of shared inherited determinants. The recent identification of the genetic causes of steatohepatitis is revealing new avenues for more effective risk stratification. Discovery of the mechanisms underpinning the detrimental effect of causal mutations has led to some breakthroughs in the comprehension of the pathophysiology of steatohepatitis. Thanks to this approach, hepatocellular fat accumulation, altered lipid droplet remodelling and lipotoxicity have now taken centre stage, while the role of adiposity and gut-liver axis alterations have been independently validated. This process could ignite a virtuous research cycle that, starting from human genomics, through omics approaches, molecular genetics and disease models, may lead to the development of new therapeutics targeted to patients at higher risk. Herein, we also review how this knowledge has been applied to: a) the study of the main PNPLA3 I148M risk variant, up to the stage of the first in-human therapeutic trials; b) highlight a role of MBOAT7 downregulation and lysophosphatidyl-inositol in steatohepatitis; c) identify IL-32 as a candidate mediator linking lipotoxicity to inflammation and liver disease. Although this precision medicine drug discovery pipeline is mainly being applied to non-alcoholic steatohepatitis, there is hope that successful products could be repurposed to treat alcohol-related liver disease as well.
Collapse
Key Words
- AA, arachidonic acid
- ASH, alcoholic steatohepatitis
- DAG, diacylglycerol
- DNL, de novo lipogenesis
- ER, endoplasmic reticulum
- FFAs, free fatty acids
- FGF19, fibroblast growth factor 19
- FLD, fatty liver disease
- FXR, farnesoid X receptor
- GCKR, glucokinase regulator
- GPR55, G protein-coupled receptor 55
- HCC, hepatocellular carcinoma
- HFE, homeostatic iron regulator
- HSC, hepatic stellate cells
- HSD17B13, hydroxysteroid 17-beta dehydrogenase 13
- IL-, interleukin-
- IL32
- LDs, lipid droplets
- LPI, lysophosphatidyl-inositol
- MARC1, mitochondrial amidoxime reducing component 1
- MBOAT7
- MBOAT7, membrane bound O-acyltransferase domain-containing 7
- NASH, non-alcoholic steatohepatitis
- PNPLA3
- PNPLA3, patatin like phospholipase domain containing 3
- PPAR, peroxisome proliferator-activated receptor
- PRS, polygenic risk score
- PUFAs, polyunsaturated fatty acids
- SREBP, sterol response element binding protein
- TAG, triacylglycerol
- TNF-α, tumour necrosis factor-α
- alcoholic liver disease
- cirrhosis
- fatty liver disease
- genetics
- interleukin-32
- non-alcoholic fatty liver disease
- precision medicine
- steatohepatitis
- therapy
Collapse
Affiliation(s)
- Cristiana Bianco
- 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
| | - Francesco Malvestiti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, 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
| |
Collapse
|
37
|
Tavaglione F, Kono N, Romeo S. Understanding the underlying molecular pathways by which Mboat7/Lpiat1 depletion induces hepatic steatosis. J Lipid Res 2021; 62:100047. [PMID: 33582144 PMCID: PMC7985689 DOI: 10.1016/j.jlr.2021.100047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 02/07/2023] Open
Affiliation(s)
- Federica Tavaglione
- Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Clinical Medicine and Hepatology Unit, Department of Internal Medicine and Geriatrics, Campus Bio-Medico University, Rome, Italy
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Science, Magna Graecia University, Catanzaro, Italy; Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden.
| |
Collapse
|
38
|
Kubota N, Fujiwara N, Hoshida Y. Clinical and Molecular Prediction of Hepatocellular Carcinoma Risk. J Clin Med 2020; 9:jcm9123843. [PMID: 33256232 PMCID: PMC7761278 DOI: 10.3390/jcm9123843] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023] Open
Abstract
Prediction of hepatocellular carcinoma (HCC) risk becomes increasingly important with recently emerging HCC-predisposing conditions, namely non-alcoholic fatty liver disease and cured hepatitis C virus infection. These etiologies are accompanied with a relatively low HCC incidence rate (~1% per year or less), while affecting a large patient population. Hepatitis B virus infection remains a major HCC risk factor, but a majority of the patients are now on antiviral therapy, which substantially lowers, but does not eliminate, HCC risk. Thus, it is critically important to identify a small subset of patients who have elevated likelihood of developing HCC, to optimize the allocation of limited HCC screening resources to those who need it most and enable cost-effective early HCC diagnosis to prolong patient survival. To date, numerous clinical-variable-based HCC risk scores have been developed for specific clinical contexts defined by liver disease etiology, severity, and other factors. In parallel, various molecular features have been reported as potential HCC risk biomarkers, utilizing both tissue and body-fluid specimens. Deep-learning-based risk modeling is an emerging strategy. Although none of them has been widely incorporated in clinical care of liver disease patients yet, some have been undergoing the process of validation and clinical development. In this review, these risk scores and biomarker candidates are overviewed, and strategic issues in their validation and clinical translation are discussed.
Collapse
|
39
|
Mashek DG. Hepatic lipid droplets: A balancing act between energy storage and metabolic dysfunction in NAFLD. Mol Metab 2020; 50:101115. [PMID: 33186758 PMCID: PMC8324678 DOI: 10.1016/j.molmet.2020.101115] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/21/2020] [Accepted: 11/06/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is defined by the abundance of lipid droplets (LDs) in hepatocytes. While historically considered simply depots for energy storage, LDs are increasingly recognized to impact a wide range of biological processes that influence cellular metabolism, signaling, and function. While progress has been made toward understanding the factors leading to LD accumulation (i.e. steatosis) and its progression to advanced stages of NAFLD and/or systemic metabolic dysfunction, much remains to be resolved. SCOPE OF REVIEW This review covers many facets of LD biology. We provide a brief overview of the major pathways of lipid accretion and degradation that contribute to steatosis and how they are altered in NAFLD. The major focus is on the relationship between LDs and cell function and the detailed mechanisms that couple or uncouple steatosis from the severity and progression of NAFLD and systemic comorbidities. The importance of specific lipids and proteins within or on LDs as key components that determine whether LD accumulation is linked to cellular and metabolic dysfunction is presented. We discuss emerging areas of LD biology and future research directions that are needed to advance our understanding of the role of LDs in NAFLD etiology. MAJOR CONCLUSIONS Impairments in LD breakdown appear to contribute to disease progression, but inefficient incorporation of fatty acids (FAs) into LD-containing triacylglycerol (TAG) and the consequential changes in FA partitioning also affect NAFLD etiology. Increased LD abundance in hepatocytes does not necessarily equate to cellular dysfunction. While LD accumulation is the prerequisite step for most NAFLD cases, the protein and lipid composition of LDs are critical factors in determining the progression from simple steatosis. Further defining the detailed molecular mechanisms linking LDs to metabolic dysfunction is important for designing effective therapeutic approaches targeting NAFLD and its comorbidities.
Collapse
Affiliation(s)
- Douglas G Mashek
- Department of Biochemistry, Molecular Biology, and Biophysics, Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Suite 6-155, 321 Church St. SE, Minneapolis, MN, 55455, USA.
| |
Collapse
|