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Ali O, Szabó A. Review of Eukaryote Cellular Membrane Lipid Composition, with Special Attention to the Fatty Acids. Int J Mol Sci 2023; 24:15693. [PMID: 37958678 PMCID: PMC10649022 DOI: 10.3390/ijms242115693] [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: 09/18/2023] [Revised: 10/24/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023] Open
Abstract
Biological membranes, primarily composed of lipids, envelop each living cell. The intricate composition and organization of membrane lipids, including the variety of fatty acids they encompass, serve a dynamic role in sustaining cellular structural integrity and functionality. Typically, modifications in lipid composition coincide with consequential alterations in universally significant signaling pathways. Exploring the various fatty acids, which serve as the foundational building blocks of membrane lipids, provides crucial insights into the underlying mechanisms governing a myriad of cellular processes, such as membrane fluidity, protein trafficking, signal transduction, intercellular communication, and the etiology of certain metabolic disorders. Furthermore, comprehending how alterations in the lipid composition, especially concerning the fatty acid profile, either contribute to or prevent the onset of pathological conditions stands as a compelling area of research. Hence, this review aims to meticulously introduce the intricacies of membrane lipids and their constituent fatty acids in a healthy organism, thereby illuminating their remarkable diversity and profound influence on cellular function. Furthermore, this review aspires to highlight some potential therapeutic targets for various pathological conditions that may be ameliorated through dietary fatty acid supplements. The initial section of this review expounds on the eukaryotic biomembranes and their complex lipids. Subsequent sections provide insights into the synthesis, membrane incorporation, and distribution of fatty acids across various fractions of membrane lipids. The last section highlights the functional significance of membrane-associated fatty acids and their innate capacity to shape the various cellular physiological responses.
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Affiliation(s)
- Omeralfaroug Ali
- Agrobiotechnology and Precision Breeding for Food Security National Laboratory, Institute of Physiology and Animal Nutrition, Department of Animal Physiology and Health, Hungarian University of Agriculture and Life Sciences, Guba Sándor Str. 40, 7400 Kaposvár, Hungary;
| | - András Szabó
- Agrobiotechnology and Precision Breeding for Food Security National Laboratory, Institute of Physiology and Animal Nutrition, Department of Animal Physiology and Health, Hungarian University of Agriculture and Life Sciences, Guba Sándor Str. 40, 7400 Kaposvár, Hungary;
- HUN-REN-MATE Mycotoxins in the Food Chain Research Group, Hungarian University of Agriculture and Life Sciences, Guba Sándor Str. 40, 7400 Kaposvár, Hungary
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2
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Korbecki J, Bosiacki M, Gutowska I, Chlubek D, Baranowska-Bosiacka I. Biosynthesis and Significance of Fatty Acids, Glycerophospholipids, and Triacylglycerol in the Processes of Glioblastoma Tumorigenesis. Cancers (Basel) 2023; 15:cancers15072183. [PMID: 37046844 PMCID: PMC10093493 DOI: 10.3390/cancers15072183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/01/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
One area of glioblastoma research is the metabolism of tumor cells and detecting differences between tumor and healthy brain tissue metabolism. Here, we review differences in fatty acid metabolism, with a particular focus on the biosynthesis of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) by fatty acid synthase (FASN), elongases, and desaturases. We also describe the significance of individual fatty acids in glioblastoma tumorigenesis, as well as the importance of glycerophospholipid and triacylglycerol synthesis in this process. Specifically, we show the significance and function of various isoforms of glycerol-3-phosphate acyltransferases (GPAT), 1-acylglycerol-3-phosphate O-acyltransferases (AGPAT), lipins, as well as enzymes involved in the synthesis of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), and cardiolipin (CL). This review also highlights the involvement of diacylglycerol O-acyltransferase (DGAT) in triacylglycerol biosynthesis. Due to significant gaps in knowledge, the GEPIA database was utilized to demonstrate the significance of individual enzymes in glioblastoma tumorigenesis. Finally, we also describe the significance of lipid droplets in glioblastoma and the impact of fatty acid synthesis, particularly docosahexaenoic acid (DHA), on cell membrane fluidity and signal transduction from the epidermal growth factor receptor (EGFR).
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Affiliation(s)
- Jan Korbecki
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
- Department of Anatomy and Histology, Collegium Medicum, University of Zielona Góra, Zyty 28 Str., 65-046 Zielona Góra, Poland
| | - Mateusz Bosiacki
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
- Department of Functional Diagnostics and Physical Medicine, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, Żołnierska 54 Str., 71-210 Szczecin, Poland
| | - Izabela Gutowska
- Department of Biochemistry and Medical Chemistry, 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
| | - Irena Baranowska-Bosiacka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
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3
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Muratovska N, Silva P, Pozdniakova T, Pereira H, Grey C, Johansson B, Carlquist M. Towards engineered yeast as production platform for capsaicinoids. Biotechnol Adv 2022; 59:107989. [PMID: 35623491 DOI: 10.1016/j.biotechadv.2022.107989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/17/2022] [Accepted: 05/18/2022] [Indexed: 12/23/2022]
Abstract
Capsaicinoids are bioactive alkaloids produced by the chili pepper fruit and are known to be the most potent agonists of the human pain receptor TRPV1 (Transient Receptor Potential Cation Channel Subfamily V Member 1). They are currently produced by extraction from chili pepper fruit or by chemical synthesis. Transfer of the biosynthetic route to a microbial host could enable more efficient capsaicinoid production by fermentation and may also enable the use of synthetic biology to create a diversity of new compounds with potentially improved properties. This review summarises the current state of the art on the biosynthesis of capsaicinoid precursors in baker's yeast, Saccharomyces cerevisiae, and discusses bioengineering strategies for achieving total synthesis from sugar.
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Affiliation(s)
- Nina Muratovska
- Division of Applied Microbiology, Lund University, Box 124, 221 00 Lund, Sweden
| | - Paulo Silva
- CBMA - Center of Molecular and Environmental Biology Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal
| | - Tatiana Pozdniakova
- CBMA - Center of Molecular and Environmental Biology Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal
| | - Humberto Pereira
- CBMA - Center of Molecular and Environmental Biology Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal
| | - Carl Grey
- Division of Biotechnology, Lund University, Box 118, SE-221 00 Lund, Sweden
| | - Björn Johansson
- CBMA - Center of Molecular and Environmental Biology Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal.
| | - Magnus Carlquist
- Division of Applied Microbiology, Lund University, Box 124, 221 00 Lund, Sweden.
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4
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Waldhart AN, Muhire B, Johnson B, Pettinga D, Madaj ZB, Wolfrum E, Dykstra H, Wegert V, Pospisilik JA, Han X, Wu N. Excess dietary carbohydrate affects mitochondrial integrity as observed in brown adipose tissue. Cell Rep 2021; 36:109488. [PMID: 34348139 PMCID: PMC8449951 DOI: 10.1016/j.celrep.2021.109488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 02/05/2021] [Accepted: 07/13/2021] [Indexed: 12/17/2022] Open
Abstract
Hyperglycemia affects over 400 million individuals worldwide. The detrimental health effects are well studied at the tissue level, but the in vivo effects at the organelle level are poorly understood. To establish such an in vivo model, we used mice lacking TXNIP, a negative regulator of glucose uptake. Examining mitochondrial function in brown adipose tissue, we find that TXNIP KO mice have a lower content of polyunsaturated fatty acids (PUFAs) in their membrane lipids, which affects mitochondrial integrity and electron transport chain efficiency and ultimately results in lower mitochondrial heat output. This phenotype can be rescued by a ketogenic diet, confirming the usefulness of this model and highlighting one facet of early cellular damage caused by excess glucose influx.
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Affiliation(s)
| | | | - Ben Johnson
- Van Andel Institute, Grand Rapids, MI 49503, USA
| | | | | | | | | | | | | | - Xianlin Han
- Barshop Institute for Longevity and Aging Studies, UT Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine, UT Health San Antonio, San Antonio, TX 78229, USA
| | - Ning Wu
- Van Andel Institute, Grand Rapids, MI 49503, USA.
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5
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Garcia Corrales AV, Haidar M, Bogie JFJ, Hendriks JJA. Fatty Acid Synthesis in Glial Cells of the CNS. Int J Mol Sci 2021; 22:ijms22158159. [PMID: 34360931 PMCID: PMC8348209 DOI: 10.3390/ijms22158159] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 12/12/2022] Open
Abstract
Fatty acids (FAs) are of crucial importance for brain homeostasis and neural function. Glia cells support the high demand of FAs that the central nervous system (CNS) needs for its proper functioning. Additionally, FAs can modulate inflammation and direct CNS repair, thereby contributing to brain pathologies such Alzheimer’s disease or multiple sclerosis. Intervention strategies targeting FA synthesis in glia represents a potential therapeutic opportunity for several CNS diseases.
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Affiliation(s)
- Aida V Garcia Corrales
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium
| | - Mansour Haidar
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium
| | - Jeroen F J Bogie
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium
| | - Jerome J A Hendriks
- Department of Immunology and Infection, Biomedical Research Institute, Hasselt University, 3590 Diepenbeek, Belgium
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6
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Nagarajan SR, Butler LM, Hoy AJ. The diversity and breadth of cancer cell fatty acid metabolism. Cancer Metab 2021; 9:2. [PMID: 33413672 PMCID: PMC7791669 DOI: 10.1186/s40170-020-00237-2] [Citation(s) in RCA: 90] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 12/16/2020] [Indexed: 12/13/2022] Open
Abstract
Tumor cellular metabolism exhibits distinguishing features that collectively enhance biomass synthesis while maintaining redox balance and cellular homeostasis. These attributes reflect the complex interactions between cell-intrinsic factors such as genomic-transcriptomic regulation and cell-extrinsic influences, including growth factor and nutrient availability. Alongside glucose and amino acid metabolism, fatty acid metabolism supports tumorigenesis and disease progression through a range of processes including membrane biosynthesis, energy storage and production, and generation of signaling intermediates. Here, we highlight the complexity of cellular fatty acid metabolism in cancer, the various inputs and outputs of the intracellular free fatty acid pool, and the numerous ways that these pathways influence disease behavior.
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Affiliation(s)
- Shilpa R Nagarajan
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Churchill Hospital, Oxford, UK
| | - Lisa M Butler
- Adelaide Medical School and Freemasons Foundation Centre for Men's Health, University of Adelaide, Adelaide, SA, Australia.,South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Andrew J Hoy
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.
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7
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Korbecki J, Kojder K, Jeżewski D, Simińska D, Tarnowski M, Kopytko P, Safranow K, Gutowska I, Goschorska M, Kolasa-Wołosiuk A, Wiszniewska B, Chlubek D, Baranowska-Bosiacka I. Expression of SCD and FADS2 Is Lower in the Necrotic Core and Growing Tumor Area than in the Peritumoral Area of Glioblastoma Multiforme. Biomolecules 2020; 10:biom10050727. [PMID: 32392704 PMCID: PMC7277411 DOI: 10.3390/biom10050727] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/29/2020] [Accepted: 05/02/2020] [Indexed: 01/31/2023] Open
Abstract
The expression of desaturases is higher in many types of cancer, and despite their recognized role in oncogenesis, there has been no research on the expression of desaturases in glioblastoma multiforme (GBM). Tumor tissue samples were collected during surgery from 28 patients (16 men and 12 women) diagnosed with GBM. The effect of necrotic conditions and nutritional deficiency (mimicking conditions in the studied tumor zones) was studied in an in vitro culture of human brain (glioblastoma astrocytoma) U-87 MG cells. Analysis of desaturase expression was made by qRT-PCR and the immunohistochemistry method. In the tumor, the expression of stearoyl–coenzyme A desaturase (SCD) and fatty acid desaturases 2 (FADS2) was lower than in the peritumoral area. The expression of other desaturases did not differ in between the distinguished zones. We found no differences in the expression of SCD, fatty acid desaturases 1 (FADS1), or FADS2 between the sexes. Necrotic conditions and nutritional deficiency increased the expression of the studied desaturase in human brain (glioblastoma astrocytoma) U-87 MG cells. The obtained results suggest that (i) biosynthesis of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) in a GBM tumor is less intense than in the peritumoral area; (ii) expressions of SCD, SCD5, FADS1, and FADS2 correlate with each other in the necrotic core, growing tumor area, and peritumoral area; (iii) expressions of desaturases in a GBM tumor do not differ between the sexes; and (iv) nutritional deficiency increases the biosynthesis of MUFA and PUFA in GBM cells.
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Affiliation(s)
- Jan Korbecki
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (K.S.); (M.G.); (D.C.)
| | - Klaudyna Kojder
- Department of Anaesthesiology and Intensive Care, Pomeranian Medical University in Szczecin, Unii Lubelskiej 1, 71-252 Szczecin, Poland;
| | - Dariusz Jeżewski
- Department of Neurosurgery and Pediatric Neurosurgery, Pomeranian Medical University in Szczecin, Unii Lubelskiej 1, 71-252 Szczecin, Poland;
- Department of Applied Neurocognitivistics, Unii Lubelskiej 1, Pomeranian Medical University in Szczecin, 71-252 Szczecin, Poland
| | - Donata Simińska
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (K.S.); (M.G.); (D.C.)
| | - Maciej Tarnowski
- Department of Physiology, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (M.T.); (P.K.)
| | - Patrycja Kopytko
- Department of Physiology, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (M.T.); (P.K.)
| | - Krzysztof Safranow
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (K.S.); (M.G.); (D.C.)
| | - Izabela Gutowska
- Department of Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland;
| | - Marta Goschorska
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (K.S.); (M.G.); (D.C.)
| | - Agnieszka Kolasa-Wołosiuk
- Department of Histology and Embryology, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (A.K.-W.); (B.W.)
| | - Barbara Wiszniewska
- Department of Histology and Embryology, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (A.K.-W.); (B.W.)
| | - Dariusz Chlubek
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (K.S.); (M.G.); (D.C.)
| | - Irena Baranowska-Bosiacka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (K.S.); (M.G.); (D.C.)
- Correspondence: ; Tel.: +48-91-466-1515; Fax: +48-91-466-1516
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8
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Karsai G, Lone M, Kutalik Z, Brenna JT, Li H, Pan D, von Eckardstein A, Hornemann T. FADS3 is a Δ14Z sphingoid base desaturase that contributes to gender differences in the human plasma sphingolipidome. J Biol Chem 2020; 295:1889-1897. [PMID: 31862735 PMCID: PMC7029104 DOI: 10.1074/jbc.ac119.011883] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 12/16/2019] [Indexed: 12/18/2022] Open
Abstract
Sphingolipids (SLs) are structurally diverse lipids that are defined by the presence of a long-chain base (LCB) backbone. Typically, LCBs contain a single Δ4E double bond (DB) (mostly d18:1), whereas the dienic LCB sphingadienine (d18:2) contains a second DB at the Δ14Z position. The enzyme introducing the Δ14Z DB is unknown. We analyzed the LCB plasma profile in a gender-, age-, and BMI-matched subgroup of the CoLaus cohort (n = 658). Sphingadienine levels showed a significant association with gender, being on average ∼30% higher in females. A genome-wide association study (GWAS) revealed variants in the fatty acid desaturase 3 (FADS3) gene to be significantly associated with the plasma d18:2/d18:1 ratio (p = -log 7.9). Metabolic labeling assays, FADS3 overexpression and knockdown approaches, and plasma LCB profiling in FADS3-deficient mice confirmed that FADS3 is a bona fide LCB desaturase and required for the introduction of the Δ14Z double bond. Moreover, we showed that FADS3 is required for the conversion of the atypical cytotoxic 1-deoxysphinganine (1-deoxySA, m18:0) to 1-deoxysphingosine (1-deoxySO, m18:1). HEK293 cells overexpressing FADS3 were more resistant to m18:0 toxicity than WT cells. In summary, using a combination of metabolic profiling and GWAS, we identified FADS3 to be essential for forming Δ14Z DB containing LCBs, such as d18:2 and m18:1. Our results unravel FADS3 as a Δ14Z LCB desaturase, thereby disclosing the last missing enzyme of the SL de novo synthesis pathway.
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Affiliation(s)
- Gergely Karsai
- Institute for Clinical Chemistry, University Hospital and University Zurich, 8091 Zürich, Switzerland
| | - Museer Lone
- Institute for Clinical Chemistry, University Hospital and University Zurich, 8091 Zürich, Switzerland
| | - Zoltán Kutalik
- University Center for Primary Care and Public Health, University of Lausanne, 1010 Lausanne, Switzerland; Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - J Thomas Brenna
- Dell Pediatric Research Institute, Departments of Chemistry, Pediatrics, and Nutrition, University of Texas, Austin, Texas 78723
| | - Hongde Li
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Duojia Pan
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Arnold von Eckardstein
- Institute for Clinical Chemistry, University Hospital and University Zurich, 8091 Zürich, Switzerland
| | - Thorsten Hornemann
- Institute for Clinical Chemistry, University Hospital and University Zurich, 8091 Zürich, Switzerland.
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9
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Jojima K, Edagawa M, Sawai M, Ohno Y, Kihara A. Biosynthesis of the anti-lipid-microdomain sphingoid base 4,14-sphingadiene by the ceramide desaturase FADS3. FASEB J 2020; 34:3318-3335. [PMID: 31916624 DOI: 10.1096/fj.201902645r] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/23/2019] [Accepted: 12/24/2019] [Indexed: 11/11/2022]
Abstract
Sphingolipids are multifunctional lipids. Among the sphingolipid-component sphingoid bases, 4,14-sphingadiene (SPD) is unique such that it has a cis double bond with a bent structure. Although SPD was discovered half a century ago, its tissue distribution, biosynthesis, and degradation remain poorly understood. Here, we established a specific and quantitative method for SPD measurement and found that SPD exists in a wide range of mammalian tissues. SPD was especially abundant in kidney, where the amount of SPD was ~2/3 of sphingosine, the most abundant sphingoid base in mammals. Although SPD is metabolized to ceramides and SPD 1-phosphate with almost the same efficiency as sphingosine, it is less susceptible to degradation by a cleavage reaction, at least in vitro. We identified the fatty acid desaturase family protein FADS3 as a ceramide desaturase that produces SPD ceramides by desaturating ceramides containing sphingosine. SPD sphingolipids were preferentially localized outside lipid microdomains, suggesting that SPD has different functions compared to other sphingoid bases in the formation of lipid microdomains. In summary, we revealed the biosynthesis and degradation pathways of SPD and its characteristic membrane localization. Our findings contribute to the elucidation of the molecular mechanism underlying the generation of sphingolipid diversity.
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Affiliation(s)
- Keisuke Jojima
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Mai Edagawa
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Megumi Sawai
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Yusuke Ohno
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Akio Kihara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
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10
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Guillocheau E, Legrand P, Rioux V. Trans-palmitoleic acid (trans-9-C16:1, or trans-C16:1 n-7): Nutritional impacts, metabolism, origin, compositional data, analytical methods and chemical synthesis. A review. Biochimie 2019; 169:144-160. [PMID: 31837411 DOI: 10.1016/j.biochi.2019.12.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 12/09/2019] [Indexed: 01/11/2023]
Abstract
Since the early 2010s, dietary trans-palmitoleic acid (trans-9-hexadecenoic acid, trans-9-C16:1 in the Δ-nomenclature, trans-C16:1 n-7 in the Ω-nomenclature, TPA) has been epidemiologically associated with a lower risk of type 2 diabetes in humans. Thanks to these findings, TPA has become a nutrient of interest. However, there is a lot of unresolved crucial questions about this dietary fatty acid. Is TPA a natural trans fatty acid? What kind of foods ensures intakes in TPA? What about its metabolism? How does dietary TPA act to prevent type 2 diabetes? What are the biological mechanisms involved in this physiological effect? Clearly, it is high time to answer all these questions with the very first review specifically dedicated to this intriguing fatty acid. Aiming at getting an overview, we shall try to give an answer to all these questions, relying on appropriate and accurate scientific results. Briefly, this review underlines that TPA is indeed a natural trans fatty acid which is metabolically linked to other well-known natural trans fatty acids. Knowledge on physiological impacts of dietary TPA is limited so far to epidemiological data, awaiting for supplementation studies. In this multidisciplinary review, we also emphasize on methodological topics related to TPA, particularly when it comes to the quantification of TPA in foods and human plasma. As a conclusion, we highlight promising health benefits of dietary TPA; however, there is a strong lack in well-designed studies in both the nutritional and the analytical area.
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Affiliation(s)
- Etienne Guillocheau
- Laboratory of Biochemistry and Human Nutrition, Agrocampus-Ouest - Rennes, France; French Dairy Interbranch Organization (CNIEL), Technical and Scientific Department - Paris, France
| | - Philippe Legrand
- Laboratory of Biochemistry and Human Nutrition, Agrocampus-Ouest - Rennes, France
| | - Vincent Rioux
- Laboratory of Biochemistry and Human Nutrition, Agrocampus-Ouest - Rennes, France.
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11
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Moderate chronic ethanol consumption exerts beneficial effects on nonalcoholic fatty liver in mice fed a high-fat diet: possible role of higher formation of triglycerides enriched in monounsaturated fatty acids. Eur J Nutr 2019; 59:1619-1632. [PMID: 31161349 DOI: 10.1007/s00394-019-02017-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 05/28/2019] [Indexed: 02/07/2023]
Abstract
PURPOSE Several clinical studies suggested that light-to-moderate alcohol intake could alleviate nonalcoholic fatty liver disease (NAFLD), but the underlying mechanism is still poorly understood. METHODS Mice fed a high-fat diet (HFD) were submitted or not to moderate ethanol intake for 3 months (ca. 10 g/kg/day) via drinking water. Biochemical, analytical and transcriptomic analyses were performed in serum and liver. RESULTS Serum ethanol concentrations in ethanol-treated HFD mice comprised between 0.5 and 0.7 g/l throughout the experiment. NAFLD improvement was observed in ethanol-treated HFD mice as assessed by reduced serum transaminase activity. This was associated with less microvesicular and more macrovacuolar steatosis, the absence of apoptotic hepatocytes and a trend towards less fibrosis. Liver lipid analysis showed increased amounts of fatty acids incorporated in triglycerides and phospholipids, reduced proportion of palmitic acid in total lipids and higher desaturation index, thus suggesting enhanced stearoyl-coenzyme A desaturase activity. mRNA expression of several glycolytic and lipogenic enzymes was upregulated. Genome-wide expression profiling and gene set enrichment analysis revealed an overall downregulation of the expression of genes involved in collagen fibril organization and leukocyte chemotaxis and an overall upregulation of the expression of genes involved in oxidative phosphorylation and mitochondrial respiratory chain complex assembly. In addition, mRNA expression of several proteasome subunits was upregulated in ethanol-treated HFD mice. CONCLUSIONS Moderate chronic ethanol consumption may alleviate NAFLD by several mechanisms including the generation of non-toxic lipid species, reduced expression of profibrotic and proinflammatory genes, restoration of mitochondrial function and possible stimulation of proteasome activity.
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Rioux V, Legrand P. Fatty Acid Desaturase 3 (FADS3) Is a Specific ∆13-Desaturase of Ruminant trans-Vaccenic Acid. Lifestyle Genom 2019; 12:18-24. [PMID: 32911476 DOI: 10.1159/000502356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 07/23/2019] [Indexed: 12/13/2022] Open
Abstract
In mammalian species, the Fatty Acid Desaturase (FADS) gene cluster includes FADS1 (∆5-desaturase), FADS2 (∆6-desaturase), and a third gene member, named FADS3. According to its high degree of nucleotide sequence homology with both FADS1and FADS2, FADS3 was promptly suspected by researchers in the field to code for a new mammalian membrane-bound fatty acid desaturase. However, no catalytic activity was attributed to the FADS3 protein for a decade, until the rat FADS3 protein was shown in vitro to be able to catalyze the unexpected ∆13-desaturation of trans-vaccenic acid, producing the trans11,cis13-conjugated linoleic acid isomer. This review summarizes the recent investigations establishing the FADS3 enzyme as a reliable mammalian trans-vaccenate ∆13-desaturase in vivo and tries to identify further unresolved issues that need to be addressed.
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Affiliation(s)
- Vincent Rioux
- Laboratoire de Biochimie et Nutrition Humaine, Agrocampus Ouest, Rennes, France,
| | - Philippe Legrand
- Laboratoire de Biochimie et Nutrition Humaine, Agrocampus Ouest, Rennes, France
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Garcia C, Guillocheau E, Richard L, Drouin G, Catheline D, Legrand P, Rioux V. Conversion of dietary trans-vaccenic acid to trans11,cis13-conjugated linoleic acid in the rat lactating mammary gland by Fatty Acid Desaturase 3-catalyzed methyl-end Δ13-desaturation. Biochem Biophys Res Commun 2018; 505:385-391. [PMID: 30262139 DOI: 10.1016/j.bbrc.2018.09.132] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 09/20/2018] [Indexed: 01/04/2023]
Abstract
In vitro, the rat Fatty Acid Desaturase 3 (FADS3) gene was shown to code for an enzyme able to catalyze the unexpected Δ13-desaturation of trans-vaccenic acid, producing the trans11,cis13-conjugated linoleic acid (CLA) isomer. FADS3 may therefore be the first methyl-end trans-vaccenate Δ13-desaturase functionally characterized in mammals, but the proof of this concept is so far lacking in vivo. The present study therefore aimed at investigating further the putative in vivo synthesis of trans11,cis13-CLA from dietary trans-vaccenic acid in rodents. During one week of pregnancy and two weeks post-partum, Sprague-Dawley female rats were fed two diets either high (10.0% of fatty acids and 3.8% of energy intake) or low (0.4% of fatty acids and 0.2% of energy intake) in trans-vaccenic acid. The trans11,cis13-CLA was specifically detected, formally identified and reproducibly quantified (0.06% of total fatty acids) in the mammary gland phospholipids of lactating female rats fed the high trans-vaccenic acid-enriched diet. This result was consistent with FADS3 mRNA expression being significantly higher in the lactating mammary gland than in the liver. Although the apparent metabolic conversion is low, this physiological evidence demonstrates the existence of this new pathway described in the lactating mammary gland and establishes the FADS3 enzyme as a reliable mammalian trans-vaccenate Δ13-desaturase in vivo.
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Affiliation(s)
- Cyrielle Garcia
- Laboratory of Biochemistry and Human Nutrition, Agrocampus Ouest, Rennes, France
| | - Etienne Guillocheau
- Laboratory of Biochemistry and Human Nutrition, Agrocampus Ouest, Rennes, France; French Dairy Interbranch Organization (CNIEL), Technical and Scientific Department, Paris, France
| | - Léo Richard
- Laboratory of Biochemistry and Human Nutrition, Agrocampus Ouest, Rennes, France
| | - Gaëtan Drouin
- Laboratory of Biochemistry and Human Nutrition, Agrocampus Ouest, Rennes, France
| | - Daniel Catheline
- Laboratory of Biochemistry and Human Nutrition, Agrocampus Ouest, Rennes, France
| | - Philippe Legrand
- Laboratory of Biochemistry and Human Nutrition, Agrocampus Ouest, Rennes, France
| | - Vincent Rioux
- Laboratory of Biochemistry and Human Nutrition, Agrocampus Ouest, Rennes, France.
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Guillocheau E, Garcia C, Drouin G, Richard L, Catheline D, Legrand P, Rioux V. Retroconversion of dietary trans-vaccenic (trans-C18:1 n-7) acid to trans-palmitoleic acid (trans-C16:1 n-7): proof of concept and quantification in both cultured rat hepatocytes and pregnant rats. J Nutr Biochem 2018; 63:19-26. [PMID: 30316033 DOI: 10.1016/j.jnutbio.2018.09.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 08/22/2018] [Accepted: 09/12/2018] [Indexed: 01/22/2023]
Abstract
Trans-palmitoleic acid (trans-C16:1 n-7 or trans-Δ9-C16:1, TPA) is believed to improve several metabolic parameters according to epidemiological data. TPA may mainly come from direct intakes: however, data are inconsistent due to its very low amount in foods. Instead, TPA might arise from dietary trans-vaccenic acid (trans-C18:1 n-7, TVA), which is more abundant in foods. TVA chain-shortening would be involved, but formal proof of concept is still lacking to our knowledge. Therefore, the present study aimed at providing in vitro and in vivo evidence of TVA retroconversion to TPA. First, fresh rat hepatocytes cultured with growing doses of TVA were able to synthesize growing amounts of TPA, according to a 10% conversion rate. In addition, TPA was found in secreted triacylglycerols (TAG). Inhibiting peroxisomal β-oxidation significantly reduced TPA synthesis, whereas no effect was observed when mitochondrial β-oxidation was blocked. Second, pregnant female rats fed a TVA-supplemented diet free of TPA did metabolize dietary TVA, leading to detectable amounts of TPA in the liver. Apart from the brain, TPA was also found in all analyzed tissues, including the mammary gland. Hepatic peroxisomal β-oxidation of dietary TVA, combined with exportation of TPA under VLDL-TAG, may explain amounts of TPA in other tissues. In conclusion, dietary TVA undergoes peroxisomal β-oxidation and yields TPA. Thus, not only TPA circulating levels in humans can be explained by dietary TPA itself, but dietary TVA is also of importance.
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Affiliation(s)
- Etienne Guillocheau
- Laboratory of Biochemistry and Human nutrition, Agrocampus-Ouest, 35042, Rennes, France; French Dairy Interbranch Organization (CNIEL), Technical and Scientific Department, 75314, Paris, France
| | - Cyrielle Garcia
- Laboratory of Biochemistry and Human nutrition, Agrocampus-Ouest, 35042, Rennes, France
| | - Gaëtan Drouin
- Laboratory of Biochemistry and Human nutrition, Agrocampus-Ouest, 35042, Rennes, France
| | - Léo Richard
- Laboratory of Biochemistry and Human nutrition, Agrocampus-Ouest, 35042, Rennes, France
| | - Daniel Catheline
- Laboratory of Biochemistry and Human nutrition, Agrocampus-Ouest, 35042, Rennes, France
| | - Philippe Legrand
- Laboratory of Biochemistry and Human nutrition, Agrocampus-Ouest, 35042, Rennes, France
| | - Vincent Rioux
- Laboratory of Biochemistry and Human nutrition, Agrocampus-Ouest, 35042, Rennes, France.
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Zhang JY, Qin X, Liang A, Kim E, Lawrence P, Park WJ, Kothapalli KSD, Brenna JT. Fads3 modulates docosahexaenoic acid in liver and brain. Prostaglandins Leukot Essent Fatty Acids 2017; 123:25-32. [PMID: 28838557 PMCID: PMC5609706 DOI: 10.1016/j.plefa.2017.07.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 06/29/2017] [Accepted: 07/05/2017] [Indexed: 10/19/2022]
Abstract
Fatty acid desaturase 3 (FADS3) is the third member of the FADS gene cluster. FADS1 and FADS2 code for enzymes required for highly unsaturated fatty acid (HUFA) biosynthesis, but FADS3 function remains elusive. We generated the first Fads3 knockout (KO) mouse with an aim to characterize its metabolic phenotype and clues to in vivo function. All mice (wild type (WT) and KO) were fed facility rodent chow devoid of HUFA. No differences in overt phenotypes (survival, fertility, growth rate) were observed. Docosahexaenoic acid (DHA, 22:6n-3) levels in the brain of postnatal day 1 (P1) KO mice were lower than the WT (P < 0.05). The ratio of docosapentaenoic acid (DPA, 22:5n-3) to DHA in P1 KO liver was higher than in WT suggesting lower desaturase activity. Concomitantly, 20:4n-6 was lower but its elongation product 22:4n-6 was greater in the liver of P1 KO mice. P1 KO liver Fads1 and Fads2 mRNA levels were significantly downregulated whereas expression levels of elongation of very long chain 2 (Elovl2) and Elovl5 genes were upregulated compared to age-matched WT. No Δ13-desaturation of vaccenic acid was observed in liver or heart in WT mice expressing FADS3 as was reported in vitro. Taken together, the fatty acid compositional results suggest that Fads3 enhances liver-mediated 22:6n-3 synthesis to support brain 22:6n-3 accretion before and during the brain growth spurt.
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Affiliation(s)
- Ji Yao Zhang
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Xia Qin
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Allison Liang
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Ellen Kim
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Peter Lawrence
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Woo Jung Park
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | | | - J Thomas Brenna
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
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Lauritzen L, Sørensen LB, Harsløf LB, Ritz C, Stark KD, Astrup A, Dyssegaard CB, Egelund N, Michaelsen KF, Damsgaard CT. Mendelian randomization shows sex-specific associations between long-chain PUFA-related genotypes and cognitive performance in Danish schoolchildren. Am J Clin Nutr 2017; 106:88-95. [PMID: 28515069 DOI: 10.3945/ajcn.117.152595] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 04/10/2017] [Indexed: 11/14/2022] Open
Abstract
Background: Dietary and endogenously formed long-chain polyunsaturated fatty acids (LCPUFAs) are hypothesized to improve cognitive development, but results are inconclusive, with suggestions of sex specificity. One study suggested that single-nucleotide polymorphisms (SNPs) rs1535 and rs174448 in the fatty acid desaturase (FADS) gene cluster have opposite effects on erythrocyte LCPUFAs at 9 mo.Objective: To explore whether SNPs in FADS and elongase (ELOVL) genes were associated with school performance in a sex-specific manner, we performed a Mendelian randomization study using data from the Optimal well-being, development and health for Danish children through a healthy New Nordic Diet (OPUS) School Meal Study with 765 Danish schoolchildren 8-11 y old.Design: Associations between selected FADS1/2 SNPs (rs1535, rs174448, and rs174468) and ELOVL5 rs2397142, whole-blood fatty acid composition, and performance in the d2 Test of Attention and a reading test were analyzed in multiple regression models including all SNPs, SNP-sex interactions, and covariates related to testing conditions.Results:FADS, rs1535 minor allele carriage associated with lower whole-blood arachidonic acid (P ≤ 0.002), and minor alleles of rs174448 tended to associate with lower docosahexaenoic acid (DHA) (P = 0.052). We identified sex interactions in 50% of the SNP performance sets. Sex-dependent associations were observed for rs174448 and rs1535 on the d2 Test of Attention outcomes (P < 0.03) and for the associations between reading scores and rs174448 and rs2397142 (P < 0.01). All of the sex-specific analyses showed associations in opposite directions in girls and boys. The minor allele carriage of rs174448 was associated with lower d2 Test of Attention performance (P < 0.02) and reading scores (P < 0.001) in boys but with better reading scores in girls (P ≤ 0.002). The associations were consistently the opposite for rs1535 minor allele carriage (P < 0.05). Associations with rs2397142 also appeared to be opposite of those of rs174448, but only for reading and not significant after adjustment for parental educational level and whole-blood DHA.Conclusions: This study showed associations between rs1535 minor allele homozygosity and rs174448 major allele carriage and improved performance in 8- to 11-y-old boys but not in girls, thereby counteracting existing sex differences. This may be a consequence of increased endogenous DHA synthesis in infancy but not at school-age. This trial was registered at clinicaltrials.gov as NCT01457794.
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Affiliation(s)
- Lotte Lauritzen
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark;
| | - Louise B Sørensen
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark
| | - Laurine B Harsløf
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark
| | - Christian Ritz
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark
| | - Ken D Stark
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada; and
| | - Arne Astrup
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark
| | - Camilla B Dyssegaard
- Department of Education, Faculty of Arts, Aarhus University, Copenhagen, Denmark
| | - Niels Egelund
- Department of Education, Faculty of Arts, Aarhus University, Copenhagen, Denmark
| | - Kim F Michaelsen
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark
| | - Camilla T Damsgaard
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark
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Vahmani P, Aalhus JL, Rolland DC, McAllister TA, Prieto N, Block HC, Proctor SD, Guan LL, Dugan MER. Sequential Feeding of Lipid Supplement Enriches Beef Adipose Tissues with 18:3n-3 Biohydrogenation Intermediates. Lipids 2017; 52:641-649. [PMID: 28547181 DOI: 10.1007/s11745-017-4259-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 04/27/2017] [Indexed: 01/16/2023]
Abstract
The present study was designed to determine if feeding steers extruded flaxseed and hay (25 and 75%; DM basis) together as a total mixed ration (TMR), or sequentially (non-TMR) would result in different enrichments of polyunsaturated fatty acids (PUFA) and their biohydrogenation intermediates (BHI) in beef adipose tissues [subcutaneous (SC) vs perirenal (PR) fat]. Forty-eight Angus cross steers (325 ± 16 kg) were stratified by weight to six pens, and pens were randomized to either TMR or non-TMR and fed ad libitum for an average of 242 days. The concentrations of α-linolenic acid increased by 18 mol% in both SC and PR in non-TMR steers compared to TMR steers (P < 0.01). trans 18:1 isomers were more concentrated in PR than SC (14.4 vs 9.5 mol%; P < 0.01) and increased by 10 mol% in both fat depots for non-TMR (P < 0.01). Other BHI including non-methylene-interrupted 18:2 (atypical dienes), conjugated linoleic acids and conjugated linolenic acids (CLnA) were affected by diet × tissue interactions (P < 0.01). The CLnA and CLA contents were higher in both fat depots when feeding the non-TMR, but the effect of diet was more pronounced in PR than in SC (P < 0.01). Atypical dienes were highest in PR from non-TMR and lowest in TMR fed steers (4.3 and 3.6 mol%) with SC contents being intermediate. The sequential feeding of lipid supplement can thus profoundly affect the enrichment of PUFA and their BHI in beef fat and their differentially enrichment is also fat depot dependant.
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Affiliation(s)
- P Vahmani
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, AB, T4L 1W1, Canada
| | - J L Aalhus
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, AB, T4L 1W1, Canada
| | - D C Rolland
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, AB, T4L 1W1, Canada
| | - T A McAllister
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, T1J 4B1, Canada
| | - N Prieto
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, AB, T4L 1W1, Canada
| | - H C Block
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, AB, T4L 1W1, Canada
| | - S D Proctor
- Metabolic and Cardiovascular Diseases Laboratory, Alberta Diabetes and Mazankowski Institutes, Li Ka Shing Centre for Health Research Innovation, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - L L Guan
- Department of Agricultural Food and Nutritional Sciences, University of Alberta, Edmonton, AB, T6G 2P5, Canada
| | - M E R Dugan
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, AB, T4L 1W1, Canada.
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18
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Garcia C, Duby C, Catheline D, Toral PG, Bernard L, Legrand P, Rioux V. Synthesis of the suspected trans-11,cis-13 conjugated linoleic acid isomer in ruminant mammary tissue by FADS3-catalyzed Δ13-desaturation of vaccenic acid. J Dairy Sci 2016; 100:783-796. [PMID: 27865506 DOI: 10.3168/jds.2016-11455] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 10/02/2016] [Indexed: 12/20/2022]
Abstract
The octadecadienoic conjugated linoleic acid (CLA) isomer with trans-11 and cis-13 double bonds (trans-11,cis-13 CLA) has been described in ruminant milk. For now, this specific CLA is suspected to derive exclusively from ruminal biohydrogenation of dietary α-linolenic acid. However, in rodents, the fatty acid desaturase 3 (FADS3) gene was recently shown to code for an enzyme able to catalyze the unexpected Δ13-desaturation of vaccenic acid, producing a Δ11,13-CLA with all the structural characteristics of the trans-11,cis-13 isomer, although no commercial standard exists for complete conclusive identification. Because the FADS3 gene has already been reported in bovine animals, we hypothesized in the present study that an alternative direct FADS3-catalyzed Δ13-desaturation of vaccenic acid in mammary tissue may therefore co-exist with α-linolenic acid biohydrogenation to explain the final ruminant milk trans-11,cis-13 CLA presence. Here, we first confirm that the FADS3 gene is present in ruminant mammal genomic sequence databases. Second, we demonstrate that the Δ11,13-CLA found in milk fat and the highly probable trans-11,cis-13 CLA isomer produced by rodent FADS3 possess exactly the same structural characteristics. Then, we show that bovine mammary MAC-T and BME-UV epithelial cells express both FADS3 and stearoyl-CoA desaturase 1 (SCD1) mRNA and are able to synthesize both the suspected trans-11,cis-13 CLA and cis-9,trans-11CLA (rumenic acid) isomers when incubated with vaccenic acid. Finally, the concomitant presence of the suspected trans-11,cis-13 CLA isomer with FADS3 mRNA was shown in goat mammary tissue, whereas both were conversely very low or even absent in goat liver. Therefore, this study provides several lines of evidence that, by analogy with rumenic acid, trans-11,cis-13 CLA may originate both from ruminal biohydrogenation and from direct FADS3-catalyzed Δ13-desaturation of vaccenic acid in mammary tissue.
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Affiliation(s)
- Cyrielle Garcia
- Laboratoire de Biochimie Agrocampus Ouest-INRA, USC1378, 35000 Rennes, France
| | - Cécile Duby
- Laboratoire de Biochimie Agrocampus Ouest-INRA, USC1378, 35000 Rennes, France
| | - Daniel Catheline
- Laboratoire de Biochimie Agrocampus Ouest-INRA, USC1378, 35000 Rennes, France
| | - Pablo G Toral
- INRA, UR1213 Herbivores, 63122 Saint-Genès-Champanelle, France
| | | | - Philippe Legrand
- Laboratoire de Biochimie Agrocampus Ouest-INRA, USC1378, 35000 Rennes, France
| | - Vincent Rioux
- Laboratoire de Biochimie Agrocampus Ouest-INRA, USC1378, 35000 Rennes, France.
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Stearoyl-CoA Desaturase 1 Is a Key Determinant of Membrane Lipid Composition in 3T3-L1 Adipocytes. PLoS One 2016; 11:e0162047. [PMID: 27632198 PMCID: PMC5025088 DOI: 10.1371/journal.pone.0162047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 08/16/2016] [Indexed: 11/19/2022] Open
Abstract
Stearoyl-CoA desaturase 1 (SCD1) is a lipogenic enzyme important for the regulation of membrane lipid homeostasis; dysregulation likely contributes to obesity associated metabolic disturbances. SCD1 catalyses the Δ9 desaturation of 12-19 carbon saturated fatty acids to monounsaturated fatty acids. To understand its influence in cellular lipid composition we investigated the effect of genetic ablation of SCD1 in 3T3-L1 adipocytes on membrane microdomain lipid composition at the species-specific level. Using liquid chromatography/electrospray ionisation-tandem mass spectrometry, we quantified 70 species of ceramide, mono-, di- and trihexosylceramide, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, bis(monoacylglycero)phosphate, phosphatidylinositol and cholesterol in 3T3-L1 adipocytes in which a 90% reduction in scd1 mRNA expression was achieved with siRNA. Cholesterol content was unchanged although decreases in other lipids resulted in cholesterol accounting for a higher proportion of lipid in the membranes. This was associated with decreased membrane lateral diffusion. An increased ratio of 24:0 to 24:1 in ceramide, mono- and dihexosylceramide, and sphingomyelin likely also contributed to this decrease in lateral diffusion. Of particular interest, we observed a decrease in phospholipids containing arachidonic acid. Given the high degree of structural flexibility of this acyl chain this will influence membrane lateral diffusion, and is likely responsible for the transcriptional activation of Lands' cycle enzymes lpcat3 and mboat7. Of relevance these profound changes in the lipidome were not accompanied by dramatic changes in gene expression in mature differentiated adipocytes, suggesting that adaptive homeostatic mechanisms to ensure partial maintenance of the biophysical properties of membranes likely occur at a post-transcriptional level.
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20
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Effect of preduodenal lipase inhibition in suckling rats on dietary octanoic acid (C8:0) gastric absorption and plasma octanoylated ghrelin concentration. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1111-1120. [DOI: 10.1016/j.bbalip.2016.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 06/13/2016] [Accepted: 06/14/2016] [Indexed: 02/06/2023]
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Zhang JY, Qin X, Park HG, Kim E, Liu G, Kothapalli KSD, Brenna JT. Alternative splicing generates novel Fads3 transcript in mice. Mol Biol Rep 2016; 43:761-766. [PMID: 27216536 DOI: 10.1007/s11033-016-4018-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 05/17/2016] [Indexed: 01/19/2023]
Abstract
Fads3 is the third member of the fatty acid desaturase gene cluster; with at least eight evolutionarily conserved alternative transcripts (AT), having no clearly established function as are known for FADS2 and FADS1. Here we present identification of a novel Fads3 transcript in mice (Fads3AT9), characterize Fads3AT9 expression in mouse tissues and evaluate correlations with metabolite profiles. Total RNA obtained from mouse tissues is reverse-transcribed into cDNA and used as template for PCR reactions. Tissue fatty acids were extracted and quantified by gas chromatography. Sequencing analysis revealed complete absence of exon 2 resulting in an open reading frame of 1239 bp, encoding a putative protein of 412 aa with loss of 37 aa compared to classical Fads3 (Fads3CS). FADS3AT9 retains all the conserved regions characteristic of front end desaturase (cytochrome b5 domain and three histidine repeats). Both Fads3CS and Fads3AT9 are ubiquitously expressed in 11 mouse tissues. Fads3AT9 abundance was greater than Fads3CS in pancreas, liver, spleen, brown adipose tissue and thymus. Fads3CS expression is low in pancreas while Fads3AT9 is over ten-fold greater abundance. The eicosanoid precursor fatty acid 20:4n - 6, the immediate desaturation product of the Fads1 coded Δ5-desaturase, was highest in pancreas where Fads3CS is low. Changes in expression patterns and fatty acid profiles suggest that Fads3AT9 may play a role in the regulation and/or biosynthesis of long chain polyunsaturated fatty acids from precursors.
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Affiliation(s)
- Ji Yao Zhang
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Xia Qin
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.,College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Hui Gyu Park
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Ellen Kim
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Guowen Liu
- College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | | | - J Thomas Brenna
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
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22
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Zhang JY, Kothapalli KS, Brenna JT. Desaturase and elongase-limiting endogenous long-chain polyunsaturated fatty acid biosynthesis. Curr Opin Clin Nutr Metab Care 2016; 19:103-10. [PMID: 26828581 PMCID: PMC4768719 DOI: 10.1097/mco.0000000000000254] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE OF REVIEW Endogenous synthesis of the long-chain polyunsaturated fatty acids (LCPUFAs) is mediated by the fatty acid desaturase (FADS) gene cluster (11q12-13.1) and elongation of very long-chain fatty acids 2 (ELOVL2) (6p24.2) and ELOVL5 (6p12.1). Although older biochemical work identified the product of one gene, FADS2, rate limiting for LCPUFA synthesis, recent studies suggest that polymorphisms in any of these genes can limit accumulation of product LCPUFA. RECENT FINDINGS Genome-wide association study (GWAS) of Greenland Inuit shows strong adaptation signals within FADS gene cluster, attributed to high omega-3 fatty acid intake, while GWAS found ELOVL2 associated with sleep duration, age and DNA methylation. ELOVL5 coding mutations cause spinocerebellar ataxia 38, and epigenetic marks were associated with depression and suicide risk. Two sterol response element binding sites were found on ELOVL5, a SREBP-1c target gene. Minor allele carriers of a 3 single nucleotide polymorphism (SNP) haplotype in ELOVL2 have decreased 22 : 6n-3 levels. Unequivocal molecular evidence shows mammalian FADS2 catalyzes direct Δ4-desaturation to yield 22 : 6n-3 and 22 : 5n-6. An SNP near FADS1 influences the levels of 5-lipoxygenase products and epigenetic alteration. SUMMARY Genetic polymorphisms within FADS and ELOVL can limit LCPUFA product accumulation at any step of the biosynthetic pathway.
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Affiliation(s)
| | | | - J. Thomas Brenna
- Corresponding author: J. Thomas Brenna, voice (607) 255-9182, fax (607) 255-1033,
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Manipulation of milk fatty acid composition in lactating cows: Opportunities and challenges. EUR J LIPID SCI TECH 2016. [DOI: 10.1002/ejlt.201400543] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Lee JM, Lee H, Kang S, Park WJ. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances. Nutrients 2016; 8:nu8010023. [PMID: 26742061 PMCID: PMC4728637 DOI: 10.3390/nu8010023] [Citation(s) in RCA: 182] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Revised: 12/07/2015] [Accepted: 12/17/2015] [Indexed: 02/07/2023] Open
Abstract
Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism.
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Affiliation(s)
- Je Min Lee
- Department of Horticultural Science, Kyungpook National University, Daegu 41566, Korea.
| | - Hyungjae Lee
- Department of Food Engineering, Dankook University, Cheonan, Chungnam 31116, Korea.
| | - SeokBeom Kang
- Citrus Research Station, National Institute of Horticultural & Herbal Science, RDA, Seogwipo 63607, Korea.
| | - Woo Jung Park
- Department of Marine Food Science and Technology, Gangneung-Wonju National University, Gangneung, Gangwon 25457, Korea.
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Dietary Caprylic Acid (C8:0) Does Not Increase Plasma Acylated Ghrelin but Decreases Plasma Unacylated Ghrelin in the Rat. PLoS One 2015. [PMID: 26196391 PMCID: PMC4509905 DOI: 10.1371/journal.pone.0133600] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Focusing on the caprylic acid (C8:0), this study aimed at investigating the discrepancy between the formerly described beneficial effects of dietary medium chain fatty acids on body weight loss and the C8:0 newly reported effect on food intake via ghrelin octanoylation. During 6 weeks, Sprague-Dawley male rats were fed with three dietary C8:0 levels (0, 8 and 21% of fatty acids) in three experimental conditions (moderate fat, caloric restriction and high fat). A specific dose-response enrichment of the stomach tissue C8:0 was observed as a function of dietary C8:0, supporting the hypothesis of an early preduodenal hydrolysis of medium chain triglycerides and a direct absorption at the gastric level. However, the octanoylated ghrelin concentration in the plasma was unchanged in spite of the increased C8:0 availability. A reproducible decrease in the plasma concentration of unacylated ghrelin was observed, which was consistent with a decrease in the stomach preproghrelin mRNA and stomach ghrelin expression. The concomitant decrease of the plasma unacylated ghrelin and the stability of its acylated form resulted in a significant increase in the acylated/total ghrelin ratio which had no effect on body weight gain or total dietary consumption. This enhanced ratio measured in rats consuming C8:0 was however suspected to increase (i) growth hormone (GH) secretion as an increase in the GH-dependent mRNA expression of the insulin like growth Factor 1 (IGF-1) was measured (ii) adipocyte diameters in subcutaneous adipose tissue without an increase in the fat pad mass. Altogether, these results show that daily feeding with diets containing C8:0 increased the C8:0 level in the stomach more than all the other tissues, affecting the acylated/total ghrelin plasma ratio by decreasing the concentration of circulating unacylated ghrelin. However, these modifications were not associated with increased body weight or food consumption.
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Druart C, Bindels LB, Schmaltz R, Neyrinck AM, Cani PD, Walter J, Ramer-Tait AE, Delzenne NM. Ability of the gut microbiota to produce PUFA-derived bacterial metabolites: Proof of concept in germ-free versus conventionalized mice. Mol Nutr Food Res 2015; 59:1603-13. [PMID: 25820326 DOI: 10.1002/mnfr.201500014] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 03/18/2015] [Accepted: 03/20/2015] [Indexed: 11/10/2022]
Abstract
SCOPE The gut microbiota is able to modulate host physiology through the production of bioactive metabolites. Our recent studies suggest that changes in gut microbiota composition upon prebiotics supplementation alter tissue levels of PUFA-derived metabolites in mice. However, in vivo evidence that gut microbes produces PUFA-derived metabolites is lacking. This study aimed to decipher the contribution of gut microbes versus that of the host in PUFA-derived metabolite production. METHODS AND RESULTS To achieve this goal, we compared the proportion of PUFA-derived metabolites and the expression of fatty acid desaturases in germ-free (GF) and conventionalized (CONV) mice fed either a low fat or Western diet. Higher concentrations of PUFA-derived metabolites were found in the colonic contents of conventionalized mice (CONV) mice compared to GF mice. The abundance of these metabolites in host tissues was modulated by dietary treatments but not by microbial status. Although microbial status did significantly influence desaturase expression, no correlations between host enzymes and tissue PUFA-derived metabolite levels were observed. CONCLUSION Together, these results highlight the ability of the gut microbiota to produce PUFA-derived metabolites from dietary PUFA. However, microbial production of these metabolites in colonic contents is not necessarily associated with modifications of their concentration in host tissues.
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Affiliation(s)
- Céline Druart
- Metabolism and Nutrition Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Laure B Bindels
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Robert Schmaltz
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Audrey M Neyrinck
- Metabolism and Nutrition Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Patrice D Cani
- Metabolism and Nutrition Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Jens Walter
- Nutrition, Microbes, and Gastrointestinal Health, Department of Agricultural, Food & Nutritional Science, Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Amanda E Ramer-Tait
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Nathalie M Delzenne
- Metabolism and Nutrition Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
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Rioux V, Choque B, Ezanno H, Duby C, Catheline D, Legrand P. Influence of the cis-9, cis-12 and cis-15 double bond position in octadecenoic acid (18:1) isomers on the rat FADS2-catalyzed Δ6-desaturation. Chem Phys Lipids 2015; 187:10-9. [DOI: 10.1016/j.chemphyslip.2015.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 02/15/2015] [Indexed: 11/30/2022]
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Saín J, González MA, Lavandera JV, Scalerandi MV, Bernal CA. Trans
fatty acid retention and conversion rates of fatty acids in tissues depend on dietary fat in mice. EUR J LIPID SCI TECH 2015. [DOI: 10.1002/ejlt.201400287] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Juliana Saín
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)Santa FeArgentina
| | - Marcela Aída González
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
| | - Jimena Verónica Lavandera
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)Santa FeArgentina
| | - María Victoria Scalerandi
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
| | - Claudio Adrián Bernal
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)Santa FeArgentina
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Ichi I, Kono N, Arita Y, Haga S, Arisawa K, Yamano M, Nagase M, Fujiwara Y, Arai H. Identification of genes and pathways involved in the synthesis of Mead acid (20:3n-9), an indicator of essential fatty acid deficiency. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:204-13. [PMID: 24184513 DOI: 10.1016/j.bbalip.2013.10.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 10/10/2013] [Accepted: 10/24/2013] [Indexed: 12/18/2022]
Abstract
In mammals, 5,8,11-eicosatrienoic acid (Mead acid, 20:3n-9) is synthesized from oleic acid during a state of essential fatty acid deficiency (EFAD). Mead acid is thought to be produced by the same enzymes that synthesize arachidonic acid and eicosapentaenoic acid, but the genes and the pathways involved in the conversion of oleic acid to Mead acid have not been fully elucidated. The levels of polyunsaturated fatty acids in cultured cells are generally very low compared to those in mammalian tissues. In this study, we found that cultured cells, such as NIH3T3 and Hepa1-6 cells, have significant levels of Mead acid, indicating that cells in culture are in an EFAD state under normal culture conditions. We then examined the effect of siRNA-mediated knockdown of fatty acid desaturases and elongases on the level of Mead acid, and found that knockdown of Elovl5, Fads1, or Fads2 decreased the level of Mead acid. This and the measured levels of possible intermediate products for the synthesis of Mead acid such as 18:2n-9, 20:1n-9 and 20:2n-9 in the knocked down cells indicate two pathways for the synthesis of Mead acid: pathway 1) 18:1n-9→(Fads2)→18:2n-9→(Elovl5)→20:2n-9→(Fads1)→20:3n-9 and pathway 2) 18:1n-9→(Elovl5)→20:1n-9→(Fads2)→20:2n-9→(Fads1)→20:3n-9.
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Affiliation(s)
- Ikuyo Ichi
- Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo 112-8610, Japan
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