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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.
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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.)
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Valentine WJ, Shimizu T, Shindou H. Lysophospholipid acyltransferases orchestrate the compositional diversity of phospholipids. Biochimie 2023; 215:24-33. [PMID: 37611890 DOI: 10.1016/j.biochi.2023.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/14/2023] [Accepted: 08/19/2023] [Indexed: 08/25/2023]
Abstract
Lysophospholipid acyltransferases (LPLATs), in concert with glycerol-3-phosphate acyltransferases (GPATs) and phospholipase A1/2s, orchestrate the compositional diversity of the fatty chains in membrane phospholipids. Fourteen LPLAT enzymes which come from two distinct families, AGPAT and MBOAT, have been identified, and in this mini-review we provide an overview of their roles in de novo and remodeling pathways of membrane phospholipid biosynthesis. Recently new nomenclature for LPLATs has been introduced (LPLATx, where x is a number 1-14), and we also give an overview of key biological functions that have been discovered for LPLAT1-14, revealed primarily through studies of LPLAT-gene-deficient mice as well as by linkages to various human diseases.
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Affiliation(s)
- William J Valentine
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, 187-8502, Japan.
| | - Takao Shimizu
- Department of Lipid Signaling, National Center for Global Health and Medicine (NCGM), Shinjuku-ku, Tokyo, 162-8655, Japan; Institute of Microbial Chemistry, Shinagawa-ku, Tokyo, 141-0021, Japan
| | - Hideo Shindou
- Department of Lipid Life Science, 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.
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Sato T, Umebayashi S, Senoo N, Akahori T, Ichida H, Miyoshi N, Yoshida T, Sugiura Y, Goto-Inoue N, Kawana H, Shindou H, Baba T, Maemoto Y, Kamei Y, Shimizu T, Aoki J, Miura S. LPGAT1/LPLAT7 regulates acyl chain profiles at the sn-1 position of phospholipids in murine skeletal muscles. J Biol Chem 2023:104848. [PMID: 37217003 PMCID: PMC10285227 DOI: 10.1016/j.jbc.2023.104848] [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: 05/11/2023] [Accepted: 05/17/2023] [Indexed: 05/24/2023] Open
Abstract
Skeletal muscle consists of both fast- and slow-twitch fibers. Phospholipids are important structural components of cellular membranes, and the diversity of their fatty acid composition affects membrane fluidity and permeability. Although some studies have shown that acyl chain species in phospholipids differ among various muscle fiber types, the mechanisms underlying these differences are unclear. To investigate this, we analyzed phosphatidylcholine (PC) and phosphatidylethanolamine (PE) molecules in the murine extensor digitorum longus (EDL; fast-twitch) and soleus (slow-twitch) muscles. In the EDL muscle, the vast majority (93.6%) of PC molecules was palmitate-containing PC (16:0-PC), whereas in the soleus muscle, in addition to 16:0-PC, 27.9% of PC molecules was stearate-containing PC (18:0-PC). Most palmitate and stearate were bound at the sn-1 position of 16:0- and 18:0-PC, respectively, and 18:0-PC was found in type I and IIa fibers. The amount of 18:0-PE was higher in the soleus than in the EDL muscle. Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) increased the amount of 18:0-PC in the EDL. Lysophosphatidylglycerol acyltransferase 1 (LPGAT1) was highly expressed in the soleus compared with that in the EDL muscle and was upregulated by PGC-1α. LPGAT1 knockout decreased the incorporation of stearate into PC and PE in vitro and ex vivo and the amount of 18:0-PC and 18:0-PE in murine skeletal muscle with an increase in the level of 16:0-PC and 16:0-PE. Moreover, knocking out LPGAT1 decreased the amount of stearate-containing-phosphatidylserine (18:0-PS), suggesting that LPGAT1 regulated the acyl chain profiles of phospholipids, namely PC, PE, and PS, in the skeletal muscle.
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Affiliation(s)
- Tomoki Sato
- Laboratory of Nutritional Biochemistry, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Shuhei Umebayashi
- Laboratory of Nutritional Biochemistry, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Nanami Senoo
- Laboratory of Nutritional Biochemistry, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Takumi Akahori
- Laboratory of Nutritional Biochemistry, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Hiyori Ichida
- Laboratory of Nutritional Biochemistry, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Noriyuki Miyoshi
- Laboratory of Biochemistry, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Takuya Yoshida
- Laboratory of Clinical Nutrition, Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, 862-8502, Japan
| | - Yuki Sugiura
- Department of Biochemistry, Keio University School of Medicine, Tokyo, 160-8582, Japan
| | - Naoko Goto-Inoue
- Department of Marine Science and Resources, College of Bioresource Sciences, Nihon University, Fujisawa, 252-0880, Japan
| | - Hiroki Kawana
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; Advanced Research & Development Programs for Medical Innovation (AMED-LEAP), Chiyoda-ku, Tokyo, 100-0004, Japan
| | - Hideo Shindou
- Department of Lipid Life Science, National Center for Global Health and Medicine, Tokyo 162-8655, Japan; Department of Lipid Medical Science, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Takashi Baba
- Laboratory of Molecular Cell Biology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, 192-0392, Japan
| | - Yuki Maemoto
- Laboratory of Molecular Cell Biology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, 192-0392, Japan
| | - Yasutomi Kamei
- Laboratory of Molecular Nutrition, Graduate School of Environmental and Life Science, Kyoto Prefectural University, Kyoto, 606-8522, Japan
| | - Takao Shimizu
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo 162-8655, Japan; Institute of Microbial Chemistry, Tokyo, 141-0021, Japan
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; Advanced Research & Development Programs for Medical Innovation (AMED-LEAP), Chiyoda-ku, Tokyo, 100-0004, Japan
| | - Shinji Miura
- Laboratory of Nutritional Biochemistry, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan.
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Abnormal male reproduction and embryonic development induced by downregulation of a phospholipid fatty acid-introducing enzyme Lpgat1 in zebrafish. Sci Rep 2022; 12:7312. [PMID: 35508627 PMCID: PMC9068807 DOI: 10.1038/s41598-022-11002-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 04/18/2022] [Indexed: 11/23/2022] Open
Abstract
Phospholipids in the membrane consist of diverse pairs of fatty acids bound to a glycerol backbone. The biological significance of the diversity, however, remains mostly unclear. Part of this diversity is due to lysophospholipid acyltransferases (LPLATs), which introduce a fatty acid into lysophospholipids. The human genome has 14 LPLATs and most of them are highly conserved in vertebrates. Here, we analyzed the function of one of these enzymes, lysophosphatidylglycerol acyltransferase 1 (Lpgat1), in zebrafish. We found that the reproduction of heterozygous (lpgat1+/−) male mutants was abnormal. Crosses between heterozygous males and wild-type females produced many eggs with no obvious cleavage, whereas eggs produced by crosses between heterozygous females and wild-type males cleaved normally. Consistent with this, spermatozoa from heterozygous males had reduced motility and abnormal morphology. We also found that the occurrence of lpgat1 homozygous (lpgat1−/−) mutants was far lower than expected. In addition, downregulation of lpgat1 by morpholino antisense oligonucleotides resulted in severe developmental defects. Lipidomic analysis revealed that selective phospholipid species with stearic acid and docosahexaenoic acid were reduced in homozygous larvae and spermatozoa from heterozygotes. These results suggest that the specific phospholipid molecular species produced by Lpgat1 have an essential role in sperm fertilization and in embryonic development.
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Xu Y, Miller PC, Phoon CK, Ren M, Nargis T, Rajan S, Hussain MM, Schlame M. LPGAT1 controls the stearate/palmitate ratio of phosphatidylethanolamine and phosphatidylcholine in sn-1 specific remodeling. J Biol Chem 2022; 298:101685. [PMID: 35131264 PMCID: PMC8892159 DOI: 10.1016/j.jbc.2022.101685] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 01/31/2022] [Accepted: 02/02/2022] [Indexed: 01/18/2023] Open
Abstract
Most mammalian phospholipids contain a saturated fatty acid at the sn-1 carbon atom and an unsaturated fatty acid at the sn-2 carbon atom of the glycerol backbone group. While the sn-2 linked chains undergo extensive remodeling by deacylation and reacylation (Lands cycle), it is not known how the composition of saturated fatty acids is controlled at the sn-1 position. Here, we demonstrate that lysophosphatidylglycerol acyltransferase 1 (LPGAT1) is an sn-1 specific acyltransferase that controls the stearate/palmitate ratio of phosphatidylethanolamine (PE) and phosphatidylcholine. Bacterially expressed murine LPGAT1 transferred saturated acyl-CoAs specifically into the sn-1 position of lysophosphatidylethanolamine (LPE) rather than lysophosphatidylglycerol and preferred stearoyl-CoA over palmitoyl-CoA as the substrate. In addition, genetic ablation of LPGAT1 in mice abolished 1-LPE:stearoyl-CoA acyltransferase activity and caused a shift from stearate to palmitate species in PE, dimethyl-PE, and phosphatidylcholine. Lysophosphatidylglycerol acyltransferase 1 KO mice were leaner and had a shorter life span than their littermate controls. Finally, we show that total lipid synthesis was reduced in isolated hepatocytes of LPGAT1 knockout mice. Thus, we conclude that LPGAT1 is an sn-1 specific LPE acyltransferase that controls the stearate/palmitate homeostasis of PE and the metabolites of the PE methylation pathway and that LPGAT1 plays a central role in the regulation of lipid biosynthesis with implications for body fat content and longevity.
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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: 49] [Impact Index Per Article: 16.3] [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.
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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.
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Sui G, Jia L, Song N, Min D, Chen S, Wu Y, Yang G. Aberrant expression of HDL-bound microRNA induced by a high-fat diet in a pig model: implications in the pathogenesis of dyslipidaemia. BMC Cardiovasc Disord 2021; 21:280. [PMID: 34090327 PMCID: PMC8180175 DOI: 10.1186/s12872-021-02084-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 05/26/2021] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND A high-fat diet can affect lipid metabolism and trigger cardiovascular diseases. A growing body of studies has revealed the HDL-bound miRNA profiles in familial hypercholesterolaemia; in sharp contrast, relevant studies on high-fat diet-induced dyslipidaemia are lacking. In the current study, HDL-bound miRNAs altered by a high-fat diet were explored to offer some clues for elucidating their effects on the pathogenesis of dyslipidaemia. METHODS Six pigs were randomly divided into two groups of three pigs each, namely, the high-fat diet and the balanced diet groups, which were fed a high-fat diet and balanced diet separately for six months. HDL was separated from plasma, which was followed by dissociation of the miRNA bound to HDL. miRNA sequencing of the isolated miRNA was performed to identify the differential expression profiles between the two groups, which was validated by real-time PCR. TargetScan, miRDB, and miRWalk were used for the prediction of genes targeted by the differential miRNAs. RESULTS Compared with the balanced diet group, the high-fat diet group had significantly higher levels of TG, TC, LDL-C and HDL-C at six months. miRNA sequencing revealed 6 upregulated and 14 downregulated HDL-bound miRNAs in the high-fat diet group compared to the balanced diet group, which was validated by real-time PCR. GO enrichment analysis showed that dysregulated miRNAs in the high-fat diet group were associated with the positive regulation of lipid metabolic processes, positive regulation of lipid biosynthetic processes, and positive regulation of Ras protein signal transduction. Insulin resistance and the Ras signalling pathway were enriched in the KEGG pathway enrichment analysis. CONCLUSIONS Twenty HDL-bound miRNAs are significantly dysregulated in high-fat diet-induced dyslipidaemia. This study presents an analysis of a new set of HDL-bound miRNAs that are altered by a high-fat diet and offers some valuable clues for novel mechanistic insights into high-fat diet-induced dyslipidaemia. Further functional verification study using a larger sample size will be required.
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Affiliation(s)
- Guoyuan Sui
- Key Laboratory of Ministry of Education for Traditional Chinese Medicine Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China
| | - Lianqun Jia
- Key Laboratory of Ministry of Education for Traditional Chinese Medicine Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China.
| | - Nan Song
- Key Laboratory of Ministry of Education for Traditional Chinese Medicine Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China
| | - Dongyu Min
- The Affiliated Hospital of Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China
| | - Si Chen
- Key Laboratory of Ministry of Education for Traditional Chinese Medicine Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China
| | - Yao Wu
- Key Laboratory of Ministry of Education for Traditional Chinese Medicine Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China
| | - Guanlin Yang
- Key Laboratory of Ministry of Education for Traditional Chinese Medicine Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China.
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The Vitamin D Receptor Regulates Glycerolipid and Phospholipid Metabolism in Human Hepatocytes. Biomolecules 2020; 10:biom10030493. [PMID: 32213983 PMCID: PMC7175212 DOI: 10.3390/biom10030493] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 03/18/2020] [Accepted: 03/20/2020] [Indexed: 12/13/2022] Open
Abstract
The vitamin D receptor (VDR) must be relevant to liver lipid metabolism because VDR deficient mice are protected from hepatosteatosis. Therefore, our objective was to define the role of VDR on the overall lipid metabolism in human hepatocytes. We developed an adenoviral vector for human VDR and performed transcriptomic and metabolomic analyses of cultured human hepatocytes upon VDR activation by vitamin D (VitD). Twenty percent of the VDR responsive genes were related to lipid metabolism, including MOGAT1, LPGAT1, AGPAT2, and DGAT1 (glycerolipid metabolism); CDS1, PCTP, and MAT1A (phospholipid metabolism); and FATP2, SLC6A12, and AQP3 (uptake of fatty acids, betaine, and glycerol, respectively). They were rapidly induced (4–6 h) upon VDR activation by 10 nM VitD or 100 µM lithocholic acid (LCA). Most of these genes were also upregulated by VDR/VitD in mouse livers in vivo. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) metabolomics demonstrated intracellular accumulation of triglycerides, with concomitant decreases in diglycerides and phosphatidates, at 8 and 24 h upon VDR activation. Significant alterations in phosphatidylcholines, increases in lyso-phosphatidylcholines and decreases in phosphatidylethanolamines and phosphatidylethanolamine plasmalogens were also observed. In conclusion, active VitD/VDR signaling in hepatocytes triggers an unanticipated coordinated gene response leading to triglyceride synthesis and to important perturbations in glycerolipids and phospholipids.
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Genome-wide scan reveals genetic divergence and diverse adaptive selection in Chinese local cattle. BMC Genomics 2019; 20:494. [PMID: 31200634 PMCID: PMC6570941 DOI: 10.1186/s12864-019-5822-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 05/21/2019] [Indexed: 01/18/2023] Open
Abstract
Background Understanding the population structure and genetic bases of well-adapted cattle breeds to local environments is one of the most essential tasks to develop appropriate genetic improvement programs. Results We performed a comprehensive study to investigate the population structure, divergence and selection signatures at genome-wide level in diverse Chinese local cattle using Bovine HD SNPs array, including two breeds from North China, one breed from Northwest China, three breeds from Southwest China and two breeds from South China. Population genetic analyses revealed the genetic structures of these populations were mostly related to the geographic locations. Notably, we detected 294 and 1263 candidate regions under selection using the di and iHS approaches, respectively. A series of group-specific and breed-specific candidate genes were identified, which are involved in immune response, sexual maturation, stature related, birth and bone weight, embryonic development, coat colors and adaptation. Furthermore, haplotype diversity and network pattern for candidate genes, including LPGAT1, LCORL, PPP1R8, RXFP2 and FANCA, suggest that these genes have been under differential selection pressures in various environmental conditions. Conclusions Our results shed insights into diverse selection during breed formation in Chinese local cattle. These findings may promote the application of genome-assisted breeding for well-adapted local breeds with economic and ecological importance. Electronic supplementary material The online version of this article (10.1186/s12864-019-5822-y) contains supplementary material, which is available to authorized users.
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Zhang X, Zhang J, Sun H, Liu X, Zheng Y, Xu D, Wang J, Jia D, Han X, Liu F, Nie J, Shi Y. Defective Phosphatidylglycerol Remodeling Causes Hepatopathy, Linking Mitochondrial Dysfunction to Hepatosteatosis. Cell Mol Gastroenterol Hepatol 2019; 7:763-781. [PMID: 30831319 PMCID: PMC6463126 DOI: 10.1016/j.jcmgh.2019.02.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Obesity promotes the development of nonalcoholic fatty liver diseases (NAFLDs), yet not all obese patients develop NAFLD. The underlying causes for this discrepancy remain elusive. LPGAT1 is an acyltransferase that catalyzes the remodeling of phosphatidylglycerol (PG), a mitochondrial phospholipid implicated in various metabolic diseases. Here, we investigated the role of LPGAT1 in regulating the onset of diet-induced obesity and its related hepatosteatosis because polymorphisms of the LPGAT1 gene promoter were strongly associated with susceptibility to obesity in Pima Indians. METHODS Mice with whole-body knockout of LPGAT1 were generated to investigate the role of PG remodeling in NAFLD. RESULTS LPGAT1 deficiency protected mice from diet-induced obesity, but led to hepatopathy, insulin resistance, and NAFLD as a consequence of oxidative stress, mitochondrial DNA depletion, and mitochondrial dysfunction. CONCLUSIONS This study identified an unexpected role of PG remodeling in obesity, linking mitochondrial dysfunction to NAFLD.
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Affiliation(s)
- Xiaoyang Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Jun Zhang
- Sam and Ann Barshop Institute for Longevity and Aging Studies, Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Haoran Sun
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Xueling Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Yue Zheng
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Dan Xu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Jianing Wang
- Sam and Ann Barshop Institute for Longevity and Aging Studies, Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Dandan Jia
- Sam and Ann Barshop Institute for Longevity and Aging Studies, Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Xianlin Han
- Sam and Ann Barshop Institute for Longevity and Aging Studies, Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Feng Liu
- Sam and Ann Barshop Institute for Longevity and Aging Studies, Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Jia Nie
- Sam and Ann Barshop Institute for Longevity and Aging Studies, Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Yuguang Shi
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China; Sam and Ann Barshop Institute for Longevity and Aging Studies, Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas.
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Li K, Olsen RE. Metabolism of sn-1(3)-Monoacylglycerol and sn-2-Monoacylglycerol in Caecal Enterocytes and Hepatocytes of Brown Trout (Salmo trutta). Lipids 2016; 52:61-71. [DOI: 10.1007/s11745-016-4215-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 11/10/2016] [Indexed: 10/20/2022]
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Agarwal AK, Tunison K, Dalal JS, Yen CLE, Farese RV, Horton JD, Garg A. Mogat1 deletion does not ameliorate hepatic steatosis in lipodystrophic (Agpat2-/-) or obese (ob/ob) mice. J Lipid Res 2016; 57:616-30. [PMID: 26880786 DOI: 10.1194/jlr.m065896] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Indexed: 12/31/2022] Open
Abstract
Reducing triacylglycerol (TAG) in the liver continues to pose a challenge in states of nonalcoholic hepatic steatosis. MonoacylglycerolO-acyltransferase (MOGAT) enzymes convert monoacylglycerol (MAG) to diacylglycerol, a precursor for TAG synthesis, and are involved in a major pathway of TAG synthesis in selected tissues, such as small intestine. MOGAT1 possesses MGAT activity in in vitro assays, but its physiological function in TAG metabolism is unknown. Recent studies suggest a role for MOGAT1 in hepatic steatosis in lipodystrophic [1-acylglycerol-3-phosphateO-acyltransferase (Agpat)2(-/-)] and obese (ob/ob) mice. To test this, we deletedMogat1in theAgpat2(-/-)andob/obgenetic background to generateMogat1(-/-);Agpat2(-/-)andMogat1(-/-);ob/obdouble knockout (DKO) mice. Here we report that, despite the absence ofMogat1in either DKO mouse model, we did not find any decrease in liver TAG by 16 weeks of age. Additionally, there were no measureable changes in plasma glucose (diabetes) and insulin resistance. Our data indicate a minimal role, if any, of MOGAT1 in liver TAG synthesis, and that TAG synthesis in steatosis associated with lipodystrophy and obesity is independent of MOGAT1. Our findings suggest that MOGAT1 likely has an alternative function in vivo.
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Affiliation(s)
- Anil K Agarwal
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Katie Tunison
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jasbir S Dalal
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Chi-Liang Eric Yen
- Gladstone Institute of Cardiovascular Disease San Francisco, San Francisco, CA 94158
| | - Robert V Farese
- Gladstone Institute of Cardiovascular Disease San Francisco, San Francisco, CA 94158
| | - Jay D Horton
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390 Division of Gastroenterology and Departments of Molecular Genetics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Abhimanyu Garg
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
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Li H, Wang T, Xu C, Wang D, Ren J, Li Y, Tian Y, Wang Y, Jiao Y, Kang X, Liu X. Transcriptome profile of liver at different physiological stages reveals potential mode for lipid metabolism in laying hens. BMC Genomics 2015; 16:763. [PMID: 26452545 PMCID: PMC4600267 DOI: 10.1186/s12864-015-1943-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 09/21/2015] [Indexed: 11/24/2022] Open
Abstract
Background Liver is an important metabolic organ that plays a critical role in lipid synthesis, degradation, and transport; however, the molecular regulatory mechanisms of lipid metabolism remain unclear in chicken. In this study, RNA-Seq technology was used to investigate differences in expression profiles of hepatic lipid metabolism-related genes and associated pathways between juvenile and laying hens. The study aimed to broaden the understanding of liver lipid metabolism in chicken, and thereby to help improve laying performance in the poultry industry. Results RNA-Seq analysis was carried out on total RNA harvested from the liver of juvenile (n = 3) and laying (n = 3) hens. Compared with juvenile hens, 2567 differentially expressed genes (1082 up-regulated and 1485 down-regulated) with P ≤ 0.05 were obtained in laying hens, and 960 of these genes were significantly differentially expressed (SDE) at a false discovery rate (FDR) of ≤0.05 and fold-change ≥2 or ≤0.5. In addition, most of the 198 SDE novel genes (91 up-regulated and 107 down-regulated) were discovered highly expressed, and 332 SDE isoforms were identified. Gene ontology (GO) enrichment and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis showed that the SDE genes were most enrichment in steroid biosynthesis, PPAR signaling pathway, biosynthesis of unsaturated fatty acids, glycerophospholipid metabolism, three amino acid pathways, and pyruvate metabolism (P ≤ 0.05). The top significantly enriched GO terms among the SDE genes included lipid biosynthesis, cholesterol and sterol metabolic, and oxidation reduction, indicating that principal lipogenesis occurred in the liver of laying hens. Conclusions This study suggests that the majority of changes at the transcriptome level in laying hen liver were closely related to fat metabolism. Some of the SDE uncharacterized novel genes and alternative splicing isoforms that were detected might also take part in lipid metabolism, although this needs further investigation. This study provides valuable information about the expression profiles of mRNAs from chicken liver, and in-depth functional investigations of these mRNAs could provide new insights into the molecular networks of lipid metabolism in chicken liver. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1943-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hong Li
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Taian Wang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Chunlin Xu
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Dandan Wang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Junxiao Ren
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Yanmin Li
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Yadong Tian
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. .,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Zhengzhou, 450002, China.
| | - Yanbin Wang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. .,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Zhengzhou, 450002, China.
| | - Yuping Jiao
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. .,Institute of Animal Husbandry and Veterinary Medicine, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, China.
| | - Xiangtao Kang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. .,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Zhengzhou, 450002, China. .,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Xiaojun Liu
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. .,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Zhengzhou, 450002, China. .,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China.
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14
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Yamashita A, Hayashi Y, Matsumoto N, Nemoto-Sasaki Y, Oka S, Tanikawa T, Sugiura T. Glycerophosphate/Acylglycerophosphate acyltransferases. BIOLOGY 2014; 3:801-30. [PMID: 25415055 PMCID: PMC4280512 DOI: 10.3390/biology3040801] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/02/2014] [Accepted: 11/05/2014] [Indexed: 11/16/2022]
Abstract
Acyl-CoA:glycerol-3-phosphate acyltransferase (GPAT) and acyl-CoA: 1-acyl-glycerol-3-phosphate acyltransferase (AGPAT) are involved in the de novo synthesis of triacylglycerol (TAG) and glycerophospholipids. Many enzymes belonging to the GPAT/AGPAT family have recently been identified and their physiological or pathophysiological roles have been proposed. The roles of GPAT/AGPAT in the synthesis of TAG and obesity-related diseases were revealed through the identification of causative genes of these diseases or analyses of genetically manipulated animals. Recent studies have suggested that some isoforms of GPAT/AGPAT family enzymes are involved in the fatty acid remodeling of phospholipids. The enzymology of GPAT/AGPAT and their physiological/pathological roles in the metabolism of glycerolipids have been described and discussed in this review.
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Affiliation(s)
- Atsushi Yamashita
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Yasuhiro Hayashi
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Naoki Matsumoto
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Yoko Nemoto-Sasaki
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Saori Oka
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Takashi Tanikawa
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Takayuki Sugiura
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
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15
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Kleberg K, Nielsen LL, Stuhr-Hansen N, Nielsen J, Hansen HS. Evaluation of the immediate vascular stability of lipoprotein lipase-generated 2-monoacylglycerol in mice. Biofactors 2014; 40:596-602. [PMID: 25359532 DOI: 10.1002/biof.1189] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 10/14/2014] [Indexed: 11/07/2022]
Abstract
2-Monoacylglycerols are gaining increasing interest as signaling lipids, beyond endocannabinoids, for example, as ligands for the receptor GPR119 and as mediators of insulin secretion. In the vascular system, they are formed by the action of lipoprotein lipase (LPL); however, their further disposition is unclear. Assuming similar affinity for uptake and incorporation into tissues of 2-oleoylglycerol and 2-oleylglyceryl ether, we have synthesized a (3)H-labeled 2-ether analog of triolein (labeled in alkyl group) and compared its disposition with (14)C-labeled triolein (labeled in glycerol) 20 min after intravenous coadministration in a ratio of 1:1 to mice. We found that peripheral tissues and the liver in particular are able to take up 2-monoacylglycerols as seen from (3)H uptake. In muscle and adipose tissue, 2-monoacylglycerols are probably further hydrolyzed as seen by an increased (3)H/(14)C ratio, whereas in the liver and the heart, data suggest that they are also subjected to re-esterification to triacylglycerol, as seen by an unchanged (3)H/(14)C ratio in the lipid fraction of the tissues. Our findings suggest that LPL-generated 2-monoacylglycerol is likely to be stable in the vascular system and thus have a potential to circulate or at least exert effects in tissues where it may be locally produced.
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Affiliation(s)
- Karen Kleberg
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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16
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Yen CLE, Nelson DW, Yen MI. Intestinal triacylglycerol synthesis in fat absorption and systemic energy metabolism. J Lipid Res 2014; 56:489-501. [PMID: 25231105 DOI: 10.1194/jlr.r052902] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The intestine plays a prominent role in the biosynthesis of triacylglycerol (triglyceride; TAG). Digested dietary TAG is repackaged in the intestine to form the hydrophobic core of chylomicrons, which deliver metabolic fuels, essential fatty acids, and other lipid-soluble nutrients to the peripheral tissues. By controlling the flux of dietary fat into the circulation, intestinal TAG synthesis can greatly impact systemic metabolism. Genes encoding many of the enzymes involved in TAG synthesis have been identified. Among TAG synthesis enzymes, acyl-CoA:monoacylglycerol acyltransferase 2 and acyl-CoA:diacylglycerol acyltransferase (DGAT)1 are highly expressed in the intestine. Their physiological functions have been examined in the context of whole organisms using genetically engineered mice and, in the case of DGAT1, specific inhibitors. An emerging theme from recent findings is that limiting the rate of TAG synthesis in the intestine can modulate gut hormone secretion, lipid metabolism, and systemic energy balance. The underlying mechanisms and their implications for humans are yet to be explored. Pharmacological inhibition of TAG hydrolysis in the intestinal lumen has been employed to combat obesity and associated disorders with modest efficacy and unwanted side effects. The therapeutic potential of inhibiting specific enzymes involved in intestinal TAG synthesis warrants further investigation.
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Affiliation(s)
- Chi-Liang Eric Yen
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI 53706.
| | - David W Nelson
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI 53706
| | - Mei-I Yen
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI 53706
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17
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Regulation of Lipid Metabolism by Palmitoleate and Eicosapentaenoic Acid (EPA) in Mice Fed a High-Fat Diet. Biosci Biotechnol Biochem 2014; 75:2401-3. [DOI: 10.1271/bbb.110509] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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18
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Nelson DW, Gao Y, Yen MI, Yen CLE. Intestine-specific deletion of acyl-CoA:monoacylglycerol acyltransferase (MGAT) 2 protects mice from diet-induced obesity and glucose intolerance. J Biol Chem 2014; 289:17338-49. [PMID: 24784138 DOI: 10.1074/jbc.m114.555961] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The absorption of dietary fat involves the re-esterification of digested triacylglycerol in the enterocytes, a process catalyzed by acyl-CoA:monoacylglycerol acyltransferase (MGAT) 2. Mice without a functional gene encoding MGAT2 (Mogat2(-/-)) are protected from diet-induced obesity. Surprisingly, these mice absorb normal amounts of dietary fat but increase their energy expenditure. MGAT2 is expressed in tissues besides intestine, including adipose tissue in both mice and humans. To test the hypothesis that intestinal MGAT2 regulates systemic energy balance, we generated and characterized mice deficient in MGAT2 specifically in the small intestine (Mogat2(IKO)). We found that, like Mogat2(-/-) mice, Mogat2(IKO) mice also showed a delay in fat absorption, a decrease in food intake, and a propensity to use fatty acids as fuel when first exposed to a high fat diet. Mogat2(IKO) mice increased energy expenditure although to a lesser degree than Mogat2(-/-) mice and were protected against diet-induced weight gain and associated comorbidities, including hepatic steatosis, hypercholesterolemia, and glucose intolerance. These findings illustrate that intestinal lipid metabolism plays a crucial role in the regulation of systemic energy balance and may be a feasible intervention target. In addition, they suggest that MGAT activity in extraintestinal tissues may also modulate energy metabolism.
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Affiliation(s)
- David W Nelson
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
| | - Yu Gao
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
| | - Mei-I Yen
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
| | - Chi-Liang Eric Yen
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
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19
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Acyltransferases and transacylases that determine the fatty acid composition of glycerolipids and the metabolism of bioactive lipid mediators in mammalian cells and model organisms. Prog Lipid Res 2014; 53:18-81. [DOI: 10.1016/j.plipres.2013.10.001] [Citation(s) in RCA: 160] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 07/20/2013] [Accepted: 10/01/2013] [Indexed: 12/21/2022]
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20
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Gaebler A, Milan R, Straub L, Hoelper D, Kuerschner L, Thiele C. Alkyne lipids as substrates for click chemistry-based in vitro enzymatic assays. J Lipid Res 2013; 54:2282-2290. [PMID: 23709689 DOI: 10.1194/jlr.d038653] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Click chemistry is evolving as a powerful tool in biological applications because it allows the sensitive and specific detection of compounds with alkyne or azido groups. Here we describe the use of alkyne lipids as substrates for in vitro enzymatic assays of lipid modifying enzymes. The small alkyne moiety is introduced synthetically at the terminus of the hydrocarbon chain of various substrate lipids. After the assay, the label is click-reacted with the azide-bearing fluorogenic dye 3-azido-7-hydroxycoumarin, followed by the separation of the lipid mix by thin-layer chromatography and fluorescence detection, resulting in high sensitivity and wide-range linearity. Kinetic analyses using alkyne-labeled substrates for lysophosphatidic acid acyltransferases, lysophosphatidylcholine acyltransferases, and ceramide synthases resulted in Michaelis-Menten constants similar to those for radiolabeled or natural substrates. We tested additional alkyne substrates for several hydrolases and acyltransferases in lipid metabolism. In this pilot study we establish alkyne lipids as a new class of convenient substrates for in vitro enzymatic assays.
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Affiliation(s)
- Anne Gaebler
- LIMES Life and Medical Sciences Institute, University of Bonn, 53115 Bonn, Germany
| | - Robin Milan
- LIMES Life and Medical Sciences Institute, University of Bonn, 53115 Bonn, Germany
| | - Leon Straub
- LIMES Life and Medical Sciences Institute, University of Bonn, 53115 Bonn, Germany
| | - Dominik Hoelper
- LIMES Life and Medical Sciences Institute, University of Bonn, 53115 Bonn, Germany
| | - Lars Kuerschner
- LIMES Life and Medical Sciences Institute, University of Bonn, 53115 Bonn, Germany
| | - Christoph Thiele
- LIMES Life and Medical Sciences Institute, University of Bonn, 53115 Bonn, Germany.
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21
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Traurig MT, Orczewska JI, Ortiz DJ, Bian L, Marinelarena AM, Kobes S, Malhotra A, Hanson RL, Mason CC, Knowler WC, Bogardus C, Baier LJ. Evidence for a role of LPGAT1 in influencing BMI and percent body fat in Native Americans. Obesity (Silver Spring) 2013; 21:193-202. [PMID: 23505186 PMCID: PMC3666094 DOI: 10.1002/oby.20243] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Accepted: 05/17/2012] [Indexed: 01/14/2023]
Abstract
OBJECTIVE A genome-wide association study (GWAS) was recently completed in 1120 Pima Indians to identify loci that influence BMI. Among the top 100 signals were three variants that mapped within the lysophosphatidylglycerol acyltransferase 1 (LPGAT1) gene. LPGAT1 belongs to a large family of acyltransferases, which are involved in a variety of biological processes including pathways that regulate energy homeostasis and body weight. Therefore LPGAT1 was analyzed as a candidate gene for obesity in Pima Indians. DESIGN AND METHODS Variants (n = 26) located within and adjacent to LPGAT1 including a novel 27bp deletion in the 5'-untranslated region identified by sequencing were genotyped in a population-based sample of 3,391 full-heritage Pima Indians living in the Gila River Indian Community. Replication of selected variants was assessed in a second sample of 3,327 mixed-heritage Native Americans from the same community. RESULTS Variants with nominal associations with BMI in each of the two independent samples (tagged by rs112662024 and rs12058008) had associations of P = 1-4 × 10(-5) in the combined sample (n = 6718). A haplotype that includes the novel 27bp deletion, which does not occur in Caucasians, showed the strongest association with BMI in the full-heritage Pima Indians. In vitro functional studies provided suggestive evidence that this 27bp deletion may affect transcriptional or posttranscriptional regulation. Analysis of LPGAT1 cDNA from human preadipocytes identified an additional exon whose sequence could potentially serve as a mitochondrial targeting peptide. CONCLUSIONS LPGAT1 is a novel gene that influences BMI in Native Americans.
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Affiliation(s)
- Michael T Traurig
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, Phoenix, Arizona, USA
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22
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Wurie HR, Buckett L, Zammit VA. Diacylglycerol acyltransferase 2 acts upstream of diacylglycerol acyltransferase 1 and utilizes nascent diglycerides and de novo synthesized fatty acids in HepG2 cells. FEBS J 2012; 279:3033-47. [PMID: 22748069 DOI: 10.1111/j.1742-4658.2012.08684.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The two diacylglycerol acyltransferases, DGAT1 and DGAT2, are known to have non-redundant functions, in spite of catalysing the same reaction and being present in the same cell types. The basis for this distinctiveness, which is reflected in the very different phenotypes of Dgat1(-/-) and Dgat2(-/-) mice, has not been resolved. Using selective inhibitors of human DGAT1 and DGAT2 on HepG2 cells and gene silencing, we show that, although DGAT2 activity accounts for a modest fraction (< 20%) of overall cellular DGAT activity, inhibition of DGAT2 activity specifically inhibits (and is rate-limiting for) the incorporation of de novo synthesized fatty acids and of glycerol into cellular and secreted triglyceride to a much greater extent than it affects the incorporation of exogenously added oleate. By contrast, inhibition of DGAT1 affects equally the incorporation of glycerol and exogenous (preformed) oleate into cellular and secreted triacylglycerol (TAG). These data indicate that DGAT2 acts upstream of DGAT1, largely determines the rate of de novo synthesis of triglyceride, and uses nascent diacylglycerol and de novo synthesized fatty acids as substrates. By contrast, the data suggest that DGAT1 functions in the re-esterification of partial glycerides generated by intracellular lipolysis, using preformed (exogenous) fatty acids. Therefore, we describe distinct but synergistic roles of the two DGATs in an integrated pathway of TAG synthesis and secretion, with DGAT2 acting upstream of DGAT1.
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Affiliation(s)
- Haja R Wurie
- Division of Metabolic and Vascular Health, Warwick Medical School, University of Warwick, Coventry, UK
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23
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Hall AM, Kou K, Chen Z, Pietka TA, Kumar M, Korenblat KM, Lee K, Ahn K, Fabbrini E, Klein S, Goodwin B, Finck BN. Evidence for regulated monoacylglycerol acyltransferase expression and activity in human liver. J Lipid Res 2012; 53:990-999. [PMID: 22394502 DOI: 10.1194/jlr.p025536] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Intrahepatic lipid accumulation is extremely common in obese subjects and is associated with the development of insulin resistance and diabetes. Hepatic diacylglycerol and triacylglycerol synthesis predominantly occurs through acylation of glycerol-3-phosphate. However, an alternative pathway for synthesizing diacylglycerol from monoacylglycerol acyltransferases (MGAT) could also contribute to hepatic glyceride pools. MGAT activity and the expression of the three genes encoding MGAT enzymes (MOGAT1, MOGAT2, and MOGAT3) were determined in liver biopsies from obese human subjects before and after gastric bypass surgery. MOGAT expression was also assessed in liver of subjects with nonalcoholic fatty liver disease (NAFLD) or control livers. All MOGAT genes were expressed in liver, and hepatic MGAT activity was readily detectable in liver lysates. The hepatic expression of MOGAT3 was highly correlated with MGAT activity, whereas MOGAT1 and MOGAT2 expression was not, and knockdown of MOGAT3 expression attenuated MGAT activity in a liver-derived cell line. Marked weight loss following gastric bypass surgery was associated with a significant reduction in MOGAT2 and MOGAT3 expression, which were also overexpressed in NAFLD subjects. These data suggest that the MGAT pathway is active and dynamically regulated in human liver and could be an important target for pharmacologic intervention for the treatment of obesity-related insulin resistance and NAFLD.
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Affiliation(s)
- Angela M Hall
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO
| | - Kou Kou
- Cardiovascular, Metabolic, and Endocrine Diseases Research Unit, Pfizer Global Research and Development, Groton, CT
| | - Zhouji Chen
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO
| | - Terri A Pietka
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO
| | - Mrudula Kumar
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO
| | - Kevin M Korenblat
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO
| | - Kyuha Lee
- Cardiovascular, Metabolic, and Endocrine Diseases Research Unit, Pfizer Global Research and Development, Groton, CT
| | - Kay Ahn
- Cardiovascular, Metabolic, and Endocrine Diseases Research Unit, Pfizer Global Research and Development, Groton, CT
| | - Elisa Fabbrini
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO
| | - Samuel Klein
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO
| | - Bryan Goodwin
- Cardiovascular, Metabolic, and Endocrine Diseases Research Unit, Pfizer Global Research and Development, Groton, CT
| | - Brian N Finck
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO;.
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Sun J, Zhang C, Lan X, Lei C, Chen H. Exploring polymorphisms and associations of the bovine MOGAT3 gene with growth traits. Genome 2011; 55:56-62. [PMID: 22185682 DOI: 10.1139/g11-077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Monoacylglycerol acyltransferase (MGAT3, also known as MOGAT3) catalyzes the synthesis of diacylglycerol (DAG) using 2-monoacylglycerol and fatty acyl coenzyme A. This enzymatic reaction is believed to be an essential and rate-limiting step for the absorption of dietary fat in the small intestine. However, similar research for the bovine MOGAT3 gene is lacking. Therefore, in this paper, polymorphisms of the bovine MOGAT3 gene were detected in 1145 individuals from five cattle breeds by DNA pooling, PCR-RFLP, and DNA sequencing methods. The results showed that 26 novel SNPs were identified, which included 16 mutations in the coding region and the others in the introns. Additionally, association analysis between two missense mutations, g.A229G and g.G1627A, and growth traits in Nanyang cattle up to 2 years of age and adult Qinchuan cattle was performed. The results indicated that polymorphisms were significantly associated with Nanyang cattle, but no convincing associations were observed for Qinchuan cattle for the studied traits.
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Affiliation(s)
- Jiajie Sun
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi, China
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25
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SNPs in the coding region of bovine MGAT2 gene are associated with body weight and weight gain. Genes Genomics 2011. [DOI: 10.1007/s13258-011-0020-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Human milk TG are a remarkable example of stereo-specific positioning of fatty acids with structures that are highly conserved and unusual. Not only does human milk contain high amounts of fat and 16:0, but ~70% of the 16:0 is esterified at the TG stereo-specifically numbered (sn)-2 position, with preferential positioning of 18:1(n-9) and 18:2(n-6) at the TG sn-1,3 positions. The milk TG structures and digestive lipases combine to enable efficient digestion and absorption of 16:0 by conserving 16:0 in sn-2 monoacylglycerols, which are absorbed, reassembled, and secreted in plasma conserving the original milk TG configuration; these studies are reviewed in this article. The reason why the mammary gland invests in enzymes to provide the infant with 20-25% milk fatty acids as 16:0 rather than selecting against 16:0 is unknown, yet likely has a purpose given the mammary gland capacity for 10:0, 12:0, and 14:0 synthesis. Recent advances in the development-, tissue-, and species-specific activity of enzymes of TG synthesis and knowledge that dietary TG structures are maintained postabsorption suggest that the purpose of the milk TG structures is more sophisticated than simply avoiding 16:0 malabsorption. The overall aim is to expand consideration of fatty acids in the infant diet from a simple view of average fatty acid compositions to the complex lipids and molecular structures in which fatty acids are provided to tissues during early life and the biology through which the unique features of human milk enable the infant to grow and thrive on a high-fat, high-saturated-fat milk diet.
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Koutsari C, Lazaridis KN. Emerging genes associated with the progression of nonalcoholic fatty liver disease. Hepatology 2010; 52:807-10. [PMID: 20812353 DOI: 10.1002/hep.23869] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Wilson RF, Hildebrand DF. Engineering Status, Challenges and Advantages of Oil Crops. ACTA ACUST UNITED AC 2010. [DOI: 10.1007/978-3-642-13440-1_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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