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Li H, Herrmann T, Seeßle J, Liebisch G, Merle U, Stremmel W, Chamulitrat W. Role of fatty acid transport protein 4 in metabolic tissues: insights into obesity and fatty liver disease. Biosci Rep 2022:BSR20211854. [PMID: 35583196 DOI: 10.1042/BSR20211854] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 11/28/2022] Open
Abstract
Fatty acid (FA) metabolism is a series of processes that provide structural substances, signalling molecules and energy. Ample evidence has shown that FA uptake is mediated by plasma membrane transporters including FA transport proteins (FATPs), caveolin-1, fatty-acid translocase (FAT)/CD36, and fatty-acid binding proteins. Unlike other FA transporters, the functions of FATPs have been controversial because they contain both motifs of FA transport and fatty acyl-CoA synthetase (ACS). The widely distributed FATP4 is not a direct FA transporter but plays a predominant function as an ACS. FATP4 deficiency causes ichthyosis premature syndrome in mice and humans associated with suppression of polar lipids but an increase in neutral lipids including triglycerides (TGs). Such a shift has been extensively characterized in enterocyte-, hepatocyte-, and adipocyte-specific Fatp4-deficient mice. The mutants under obese and non-obese fatty livers induced by different diets persistently show an increase in blood non-esterified free fatty acids and glycerol indicating the lipolysis of TGs. This review also focuses on FATP4 role on regulatory networks and factors that modulate FATP4 expression in metabolic tissues including intestine, liver, muscle, and adipose tissues. Metabolic disorders especially regarding blood lipids by FATP4 deficiency in different cell types are herein discussed. Our results may be applicable to not only patients with FATP4 mutations but also represent a model of dysregulated lipid homeostasis, thus providing mechanistic insights into obesity and development of fatty liver disease.
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Lee JG, Kim G, Park SG, Yon JM, Yeom J, Song HE, Cheong SA, Lim JS, Sung YH, Kim K, Yoo HJ, Hong EJ, Nam KH, Seong JK, Kim CJ, Nam SY, Baek IJ. Lipid signatures reflect the function of the murine primary placentation. Biol Reprod 2021; 106:583-596. [PMID: 34850819 DOI: 10.1093/biolre/ioab219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/02/2021] [Accepted: 11/23/2021] [Indexed: 11/13/2022] Open
Abstract
The placenta regulates maternal-fetal communication, and its defect leads to significant pregnancy complications. The maternal and embryonic circulations are primitively connected in early placentation, but the function of the placenta during this developmentally essential period is relatively unknown. We thus performed a comparative proteomic analysis of the placenta before and after primary placentation and found that the metabolism and transport of lipids were characteristically activated in this period. The placental fatty acid (FA) carriers in specific placental compartments were upregulated according to gestational age, and metabolomic analysis also showed that the placental transport of FAs increased in a time-dependent manner. Further analysis of two mutant mice models with embryonic lethality revealed that lipid-related signatures could reflect the functional state of the placenta. Our findings highlight the importance of the nutrient transport function of the primary placenta in the early gestational period and the role of lipids in embryonic development.
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Affiliation(s)
- Jong Geol Lee
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Korea Mouse Phenotyping Center, Seoul, Republic of Korea
| | - Globinna Kim
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Asan Medical Institute of Convergence Science and Technology (AMIST), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Seul Gi Park
- College of Veterinary Medicine, Chungbuk National University, Cheongju, Republic of Korea.,Biomedical Mouse Resource Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongwon-Gun, Republic of Korea
| | - Jung-Min Yon
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jeonghun Yeom
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Ha Eun Song
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Asan Medical Institute of Convergence Science and Technology (AMIST), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Seung-A Cheong
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Korea Mouse Phenotyping Center, Seoul, Republic of Korea
| | - Joon Seo Lim
- Clinical Research Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Young Hoon Sung
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Asan Medical Institute of Convergence Science and Technology (AMIST), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Kyunggon Kim
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Asan Medical Institute of Convergence Science and Technology (AMIST), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Hyun Ju Yoo
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Korea Mouse Phenotyping Center, Seoul, Republic of Korea.,Asan Medical Institute of Convergence Science and Technology (AMIST), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Eui-Ju Hong
- College of Veterinary Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Ki-Hoan Nam
- Korea Mouse Phenotyping Center, Seoul, Republic of Korea.,Biomedical Mouse Resource Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongwon-Gun, Republic of Korea
| | - Je Kyung Seong
- Korea Mouse Phenotyping Center, Seoul, Republic of Korea.,College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Chong Jai Kim
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sang-Yoon Nam
- College of Veterinary Medicine, Chungbuk National University, Cheongju, Republic of Korea
| | - In-Jeoung Baek
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Korea Mouse Phenotyping Center, Seoul, Republic of Korea.,Asan Medical Institute of Convergence Science and Technology (AMIST), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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3
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Abstract
Lipid accumulation in mammals has been widely studied for decades due to its significant association with obesity in humans and meat quality in livestock animals. Fatty acid transport 1 (FATP1) is an evolutionarily conserved protein that localizes to the plasma membrane to enhance the transportation of fatty acids (FAs). In line with this function, FATP1 is involved in the metabolism of FAs, including their esterification and oxidation. In addition, the expression of FATP1 can be regulated by several energy-related factors, such as insulin and PPAR activators and transcription factors. These events connect FATP1 with cellular lipid accumulation. Recently, several studies have suggested that FATP1 acts as a facilitator in cellular lipid accumulation, whereas others hold a contrary view. Here, we will review these data and probe the possibility that FATP1 acts as a regulator in lipid accumulation, which will provide effective information for studies on the relationship between FATP1 and obesity in humans and meat quality in livestock animals.
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Serrano A, Asnani-Kishnani M, Couturier C, Astier J, Palou A, Landrier JF, Ribot J, Bonet ML. DNA Methylation Changes are Associated with the Programming of White Adipose Tissue Browning Features by Resveratrol and Nicotinamide Riboside Neonatal Supplementations in Mice. Nutrients 2020; 12:E461. [PMID: 32059412 DOI: 10.3390/nu12020461] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/06/2020] [Accepted: 02/08/2020] [Indexed: 12/22/2022] Open
Abstract
Neonatal supplementation with resveratrol (RSV) or nicotinamide riboside (NR) programs in male mice brown adipocyte-like features in white adipose tissue (WAT browning) together with improved metabolism in adulthood. We tested the involvement in this programming of long-term epigenetic changes in two browning-related genes that are overexpressed in WAT of supplemented mice, Slc27a1 and Prdm16. Suckling mice received orally the vehicle, RSV or NR from postnatal days 2-to-20. After weaning (d21) onto a chow diet, male mice were habituated to a normal-fat diet (NFD) starting d75, and split on d90 into continuation on the NFD or switching to a high-fat diet (HFD) until euthanization on d164. CpG methylation by bisulfite-sequencing was analyzed on inguinal WAT. Both treatments modified methylation marks in Slc27a1 and Prdm16 and the HFD-dependent dynamics of these marks in the adult WAT, with distinct and common effects. The treatments also affected gene expression of de novo DNA methylases in WAT of young animals (euthanized at d35 in independent experiments). Studies in 3T3-L1 adipocytes indicated the direct effects of RSV and NR on the DNA methylation machinery and favoring browning features. The results support epigenetic effects being involved in WAT programming by neonatal RSV or NR supplementation in male mice.
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Mendes T, Silva L, Almeida D, Antunes A. Neofunctionalization of the UCP1 mediated the non-shivering thermogenesis in the evolution of small-sized placental mammals. Genomics 2020; 112:2489-98. [PMID: 32027956 DOI: 10.1016/j.ygeno.2020.01.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 01/14/2020] [Accepted: 01/31/2020] [Indexed: 12/25/2022]
Abstract
The acquisition of UCP1-mediated non-shivering thermogenesis (NST) was an important event during the evolution of mammals. Here, we assessed the thermogenic neofunctionalization that occurred in the mammalian UCP1, by performing detailed comparative evolutionary genomics analyses (including phylogenetic and selection analyses) of the UCP family members across all major vertebrate classes. Heterogeneously distributed positive selection signatures were found in several UCPs, being preferably located in the mitochondrial matrix domains. Additionally, comparisons with non-mammalian orthologs showed increased evolutionary rates of the mammalian UCP1, not observable in the phylogenetically related UCP2 and UCP3 paralogs. Also, parallel signatures of episodic positive selection (ω > 1) were found in the ancestral branches of both Glires (rodents and lagomorphs) and Afroinsectivores (afrosoricids and macroscelids), underlining the importance of the UCP1 thermogenic activity in these mammalian groups. Finally, we hypothesize that the independent positive selection events that occurred in these two lineages resulted in two UCP1-mediated NST approaches, namely the cold acute response in the Glires and the reproduction success enhancement in the Afroinsectivores.
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Zhao Z, Tian H, Shi B, Jiang Y, Liu X, Hu J. Transcriptional Regulation of the Bovine Fatty Acid Transport Protein 1 Gene by Krüppel-Like Factors 15. Animals (Basel) 2019; 9:ani9090654. [PMID: 31491871 PMCID: PMC6769441 DOI: 10.3390/ani9090654] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Revised: 08/29/2019] [Accepted: 08/30/2019] [Indexed: 12/27/2022] Open
Abstract
Simple Summary The nutritional value and qualities of beef are enhanced when the unsaturated fatty acid content is increased. Fatty acid transport protein 1 (FATP1), also called SLC27A1, an integral membrane protein that facilitates long-chain fatty acid influx, is involved in the genetic network for oleic acid synthesis in beef. Polymorphisms in bovine SLC27A1 gene are most significantly associated with oleic acid. Its expression exhibits significant positive correlations with bovine intramuscular fat content in the longissimus thoracis muscle. However, the transcription factors that contribute to the control and regulation of its expression have not been characterized extensively. In this study, we determined the tissue distribution of SLC27A1 mRNA and found that bovine SLC27A1 was highly expressed in subcutaneous adipose tissue and the longissimus thoracis muscle. Furthermore, we analyzed the molecular mechanisms involved in SLC27A1 regulation and found that the transcriptional activity of SLC27A1 gene was dependent on KLF15 transcription factor. These results may lead to an enhanced understanding of the regulation of SLC27A1 expression in other models, as well as provide new insights into the regulatory mechanism and biological functions of the SLC27A1 gene in determining the lipid composition in beef. Abstract Oleic acid is a major monounsaturated fatty acid, which accounts for about 33% of the fatty acid content in beef and is considered to have the least negative effect on serum cholesterol levels. Fatty acid transport protein 1 (FATP1), an integral membrane protein that facilitates long-chain fatty acid (LCFA) influx, is involved in the genetic network for oleic acid synthesis in beef. Its expression exhibits significant positive correlations with intramuscular fat (IMF) content in the longissimus thoracis. However, the expression mechanism of SLC27A1 or FATP1 is still unclear. To elucidate the molecular mechanisms involved in bovine SLC27A1 regulation, we cloned and characterized the promoter region of SLC27A1. By applying 5′-rapid amplification of cDNA end analysis, we identified two alternative splice variants of this gene. Using a series of 5′ deletion promoter plasmids in luciferase reporter assays, we found that the core promoter was 96 base pairs upstream from the transcription initiation site. Electrophoretic mobility shift assay combined with a site-directed mutation experiment demonstrated that KLF15 binding to the promoter region drives the SLC27A1 transcription. KLF15 plays an essential role in adipogenesis and skeletal muscle lipid flux. Thus, these results might provide further information on the regulatory roles of SLC27A1 gene in mediating the lipid composition in beef.
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Affiliation(s)
- Zhidong Zhao
- College of Animal Science and Technology & Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China.
| | - Hongshan Tian
- College of Animal Science and Technology & Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China.
| | - Bingang Shi
- College of Animal Science and Technology & Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China.
| | - Yanyan Jiang
- College of Animal Science and Technology & Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China.
| | - Xiu Liu
- College of Animal Science and Technology & Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China.
| | - Jiang Hu
- College of Animal Science and Technology & Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China.
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7
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Zhang W, Chen R, Yang T, Xu N, Chen J, Gao Y, Stetler RA. Fatty acid transporting proteins: Roles in brain development, aging, and stroke. Prostaglandins Leukot Essent Fatty Acids 2018; 136:35-45. [PMID: 28457600 PMCID: PMC5650946 DOI: 10.1016/j.plefa.2017.04.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Revised: 04/16/2017] [Accepted: 04/20/2017] [Indexed: 12/18/2022]
Abstract
Polyunsaturated fatty acids are required for the brain development and significantly impact aging and stroke. Due to the hydrophobicity of fatty acids, fatty acids transportation related proteins that include fatty acid binding proteins (FABPs), long chain acyl-coA synthase (ACS), fatty acid transportation proteins (FATPs), fatty acid translocase (FAT/CD36) and newly reported major facilitator superfamily domain-containing protein (Mfsd2a) play critical roles in the uptake of various fatty acids, especially polyunsaturated fatty acids. They are not only involved in neurodevelopment, but also have great impact on neurological disease, such as aging related dementia and stroke.
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Affiliation(s)
- Wenting Zhang
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Ruiying Chen
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Tuo Yang
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Na Xu
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Jun Chen
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Education and Clinical Center Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
| | - R Anne Stetler
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Education and Clinical Center Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA.
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8
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Habashy WS, Milfort MC, Fuller AL, Attia YA, Rekaya R, Aggrey SE. Effect of heat stress on protein utilization and nutrient transporters in meat-type chickens. Int J Biometeorol 2017; 61:2111-2118. [PMID: 28799035 DOI: 10.1007/s00484-017-1414-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 06/07/2023]
Abstract
The aim of this study was to investigate the effect of heat stress (HS) on digestibility of protein and fat and the expression of nutrient transporters in broilers. Forty-eight male Cobb500 chicks were used in this study. At day 14, birds were randomly divided into two groups and kept under either constant normal temperature (25 °C) or high temperature (35 °C) in individual cages. Five birds per treatment at 1 and 12 days post-treatment were euthanized, and Pectoralis major (P. major) and ileum were sampled for gene expression analysis. At day 33, ileal contents were collected and used for digestibility analysis. The total consumption and retention of protein and fat were significantly lower in the HS group compared to the control group. Meanwhile, the retention of crude protein per BWG was significantly higher in the HS group compared to the control group. In P. major and ileum tissues at day 1, transporters FATP1 and SGLT1 were down-regulated in the HS group. Meanwhile, FABP1 and PepT1 were down-regulated only in the ileum of the HS group. The converse was shown in P. major. The nutrient transporter FABP1 at day 12 post-HS was down-regulated in the P. major and ileum, but GLUT1 and PepT2 were down-regulated only in the ileum, and PepT1 was down-regulated only in the P. major compared with the control group. These changes in nutrient transporters suggest that high ambient temperature might change the ileum and P. major lipids, glucose, and oligopeptide transporters.
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Affiliation(s)
- Walid S Habashy
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA, 30602, USA
- Department of Animal and Poultry Production, Damanhour University, Damanhour, Al-Behira, Egypt
| | - Marie C Milfort
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA, 30602, USA
| | - Alberta L Fuller
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA, 30602, USA
| | - Youssef A Attia
- Department of Animal and Poultry Production, Damanhour University, Damanhour, Al-Behira, Egypt
- Arid Land Agriculture Department, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Romdhane Rekaya
- Department of Animal and Dairy Sciences, University of Georgia, Athens, GA, 30602, USA
| | - Samuel E Aggrey
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA, 30602, USA.
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Li W, Yang X, Zheng T, Xing S, Wu Y, Bian F, Wu G, Li Y, Li J, Bai X, Wu D, Jia X, Wang L, Zhu L, Jin S. TNF-α stimulates endothelial palmitic acid transcytosis and promotes insulin resistance. Sci Rep 2017; 7:44659. [PMID: 28304381 DOI: 10.1038/srep44659] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 02/13/2017] [Indexed: 01/15/2023] Open
Abstract
Persistent elevation of plasma TNF-α is a marker of low grade systemic inflammation. Palmitic acid (PA) is the most abundant type of saturated fatty acid in human body. PA is bound with albumin in plasma and could not pass through endothelial barrier freely. Albumin-bound PA has to be transported across monolayer endothelial cells through intracellular transcytosis, but not intercellular diffusion. In the present study, we discovered that TNF-α might stimulate PA transcytosis across cardiac microvascular endothelial cells, which further impaired the insulin-stimulated glucose uptake by cardiomyocytes and promoted insulin resistance. In this process, TNF-α-stimulated endothelial autophagy and NF-κB signaling crosstalk with each other and orchestrate the whole event, ultimately result in increased expression of fatty acid transporter protein 4 (FATP4) in endothelial cells and mediate the increased PA transcytosis across microvascular endothelial cells. Hopefully the present study discovered a novel missing link between low grade systemic inflammation and insulin resistance.
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Abstract
The uptake and metabolism of long chain fatty acids (LCFA) are critical to many physiological and cellular processes. Aberrant accumulation or depletion of LCFA underlie the pathology of numerous metabolic diseases. Protein-mediated transport of LCFA has been proposed as the major mode of LCFA uptake and activation. Several proteins have been identified to be involved in LCFA uptake. This review focuses on the SLC27 family of fatty acid transport proteins, also known as FATPs, with an emphasis on the gain- and loss-of-function animal models that elucidate the functions of FATPs in vivo and how these transport proteins play a role in physiological and pathological situations.
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Affiliation(s)
- Courtney M Anderson
- Metabolic Biology, Department of Nutritional Sciences and Toxicology, University of California Berkeley, CA, USA
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Sánchez-gurmaches J, Cruz-garcia L, Gutiérrez J, Navarro I. mRNA expression of fatty acid transporters in rainbow trout: in vivo and in vitro regulation by insulin, fasting and inflammation and infection mediators. Comp Biochem Physiol A Mol Integr Physiol 2012; 163:177-88. [DOI: 10.1016/j.cbpa.2012.06.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 06/24/2012] [Accepted: 06/27/2012] [Indexed: 01/07/2023]
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12
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Rahman SM, Janssen RC, Choudhury M, Baquero KC, Aikens RM, de la Houssaye BA, Friedman JE. CCAAT/enhancer-binding protein β (C/EBPβ) expression regulates dietary-induced inflammation in macrophages and adipose tissue in mice. J Biol Chem 2012; 287:34349-60. [PMID: 22902781 DOI: 10.1074/jbc.m112.410613] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Strong evidence exists for a link between chronic low level inflammation and dietary-induced insulin resistance; however, little is known about the transcriptional networks involved. Here we show that high fat diet (HFD) or saturated fatty acid exposure directly activates CCAAT/enhancer-binding protein β (C/EBPβ) protein expression in liver, adipocytes, and macrophages. Global C/EBPβ deletion prevented HFD-induced inflammation and surprisingly increased mitochondrial gene expression in white adipose tissue along with brown adipose tissue markers PRDM16, CIDEa, and UCP1, consistent with a resistance to HFD-induced obesity. In isolated peritoneal macrophages from C/EBPβ(-/-) mice, the anti-inflammatory gene LXRα and its targets SCD1 and DGAT2 were strikingly up-regulated along with IL-10, while NLRP3, a gene important for activating the inflammasome, was suppressed in response to palmitate. Using RAW 264.7 macrophage cells or 3T3-L1 adipocytes, C/EBPβ knockdown prevented palmitate-induced inflammation and p65-NFκB DNA binding activity, while C/EBPβ overexpression induced NFκB binding, JNK activation, and pro-inflammatory cytokine gene expression directly. Finally, chimeric bone marrow mice transplanted with bone marrow lacking C/EBPβ(-/-) demonstrated reduced systemic and adipose tissue inflammatory markers, macrophage content, and maintained insulin sensitivity on HFD. Taken together, these results demonstrate that HFD or palmitate exposure triggers C/EBPβ expression that controls expression of distinct aspects of alternative macrophage activation. Reducing C/EBPβ in macrophages confers protection from HFD-induced systemic inflammation and insulin resistance, suggesting it may be an attractive therapeutic target for ameliorating obesity-induced inflammatory responses.
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Affiliation(s)
- Shaikh M Rahman
- Department of Pediatrics, University of Colorado Denver School of Medicine, Aurora, Colorado 80045, USA
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13
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Softic S, Kirby M, Berger NG, Shroyer NF, Woods SC, Kohli R. Insulin concentration modulates hepatic lipid accumulation in mice in part via transcriptional regulation of fatty acid transport proteins. PLoS One 2012; 7:e38952. [PMID: 22745692 PMCID: PMC3380053 DOI: 10.1371/journal.pone.0038952] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 05/16/2012] [Indexed: 12/18/2022] Open
Abstract
Background Fatty liver disease (FLD) is commonly associated with insulin resistance and obesity, but interestingly it is also observed at low insulin states, such as prolonged fasting. Thus, we asked whether insulin is an independent modulator of hepatic lipid accumulation. Methods/Principal Findings In mice we induced, hypo- and hyperinsulinemia associated FLD by diet induced obesity and streptozotocin treatment, respectively. The mechanism of free fatty acid induced steatosis was studied in cell culture with mouse liver cells under different insulin concentrations, pharmacological phosphoinositol-3-kinase (PI3K) inhibition and siRNA targeted gene knock-down. We found with in vivo and in vitro models that lipid storage is increased, as expected, in both hypo- and hyperinsulinemic states, and that it is mediated by signaling through either insulin receptor substrate (IRS) 1 or 2. As previously reported, IRS-1 was up-regulated at high insulin concentrations, while IRS-2 was increased at low levels of insulin concentration. Relative increase in either of these insulin substrates, was associated with an increase in liver-specific fatty acid transport proteins (FATP) 2&5, and increased lipid storage. Furthermore, utilizing pharmacological PI3K inhibition we found that the IRS-PI3K pathway was necessary for lipogenesis, while FATP responses were mediated via IRS signaling. Data from additional siRNA experiments showed that knock-down of IRSs impacted FATP levels. Conclusions/Significance States of perturbed insulin signaling (low-insulin or high-insulin) both lead to increased hepatic lipid storage via FATP and IRS signaling. These novel findings offer a common mechanism of FLD pathogenesis in states of both inadequate (prolonged fasting) and ineffective (obesity) insulin signaling.
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Affiliation(s)
- Samir Softic
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Pediatrics, Riley Hospital for Children, Indiana University, Indianapolis, Indiana, United States of America
| | - Michelle Kirby
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Nicholas G. Berger
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Noah F. Shroyer
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Stephen C. Woods
- Metabolic Diseases Institute, Obesity Research Center, Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Rohit Kohli
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- * E-mail:
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14
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Lv Y, Wei C, Zhang L, Lu G, Liu K, Du L. Association Between Polymorphisms in theSLC27A1Gene and Milk Production Traits in Chinese Holstein Cattle. Anim Biotechnol 2011; 22:1-6. [DOI: 10.1080/10495398.2011.527567] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Thompson BR, Lobo S, Bernlohr DA. Fatty acid flux in adipocytes: the in's and out's of fat cell lipid trafficking. Mol Cell Endocrinol 2010; 318:24-33. [PMID: 19720110 PMCID: PMC2826553 DOI: 10.1016/j.mce.2009.08.015] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 08/19/2009] [Accepted: 08/20/2009] [Indexed: 12/21/2022]
Abstract
The trafficking of fatty acids into and out of adipocytes is regulated by a complex series of proteins and enzymes and is under control by a variety of hormonal and metabolic factors. The biochemical basis of fatty acid influx, despite its widespread appreciation, remains enigmatic with regard to the biophysical and biochemical properties that facilitate long-chain fatty acid uptake. Fatty acid efflux is initiated by hormonally controlled lipolysis of the droplet stores and produces fatty acids that must transit from their site of production to the plasma membrane and subsequently out of the cells. This review will focus on the "in's and out's" of fatty acid trafficking and summarize the current concepts in the field.
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Affiliation(s)
- Brian R Thompson
- Department of Biochemistry, Molecular Biology and Biophysics, The University of Minnesota-Twin Cities, 321 Church St. SE, Minneapolis, MN 55455, USA
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16
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Gutgesell A, Ringseis R, Eder K. Short communication: Dietary conjugated linoleic acid down-regulates fatty acid transporters in the mammary glands of lactating rats. J Dairy Sci 2009; 92:1169-73. [DOI: 10.3168/jds.2008-1640] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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17
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Ordovas L, Zaragoza P, Altarriba J, Rodellar C. Identification of 14 new single nucleotide polymorphisms in the bovine SLC27A1 gene and evaluation of their association with milk fat content. J DAIRY RES 2008; 75:129-34. [DOI: 10.1017/s0022029907002919] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The solute carrier family 27 member 1 (SLC27A1) is an integral membrane protein involved in the transport of long-chain fatty acids across the plasma membrane. This protein has been implicated in diet-induced obesity and is thought to be important in the control of energy homeostasis. In previous reports, our group described the isolation and characterization of the bovineSLC27A1gene. The bovine gene is organized in 13 exons spanning over more than 40 kb of genomic DNA and maps in BTA 7 where several quantitative trait loci for fat related traits have been described. Because of its key role in lipid metabolism and its genomic localization, in the present work the search for variability in the bovineSLC27A1gene was carried out with the aim of evaluating its potential association with milk fat content in dairy cattle. By sequencing analysis of all exons and flanking regions 14 new single nucleotide polymorphisms (SNPs) were identified: 1 in the promoter, 7 in introns and 6 in exons. Allele frequencies of all the SNPs were calculated by minisequencing analysis in two groups of Holstein-Friesian animals with highest and lowest milk-fat content estimated breeding values as well as in animals of two Spanish cattle breeds, Asturiana de los Valles and Menorquina. In the conditions assayed, no significant differences between Holstein-Friesian groups were found for any of the SNPs, suggesting that theSLC27A1gene may have a poor or null effect on milk fat content. In Asturiana and Menorquina breeds all the positions were polymorphic with the exception of SNPs 1 and 8 in which C allele was fixed in both of them.
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18
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Abstract
We generated preadipocyte cell lines impaired in adrenomedullin production through integration of an adrenomedullin small interfering RNA expression vector. The reduction of adrenomedullin synthesis strongly accelerated adipose differentiation. These results were bolstered when overexpression of active adrenomedullin peptide led to delayed differentiation. Therefore, we propose that adrenomedullin is an antiadipogenic factor. Moreover, we checked whether insulin, a proadipogenic factor, regulates expression of adrenomedullin. We observed that insulin had an inhibitory effect on adrenomedullin expression in isolated human adipocyte cells. This response was dose dependent and was reversed by resistin, a new anti-insulin agent. We quantified circulating adrenomedullin in healthy obese patients and observed a threefold increase of adrenomedullin compared with lean patients. Furthermore, adrenomedullin plasma levels are negatively correlated to plasma insulin levels in these obese patients. The insulin inhibitory response was also observed in vivo in Sprague-Dawley rats but not in the insulin-resistant Zucker rat, suggesting that adrenomedullin expression is upregulated in insulin-resistant adipose cells. Using adrenomedullin promoter-luciferase reporter gene constructs, we have shown that the adrenomedullin response to insulin is mediated by insulin-responsive elements. These findings provide new insight into fat mass development and the relationship between obesity and elevated circulating adrenomedullin levels in diabetic patients.
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Affiliation(s)
- Romain Harmancey
- I2MR INSERM U858, Laboratoire de Pharmacologie, Faculté de Médecine, Universite Paul Sabatier, Institut Louis Bugnard IFR31, 37 allées Jules Guesde, 31000 Toulouse, France
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19
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Ordovás L, Roy R, Zaragoza P, Rodellar C. Structural and functional characterization of the bovine solute carrier family 27 member 1 (SLC27A1) gene. Cytogenet Genome Res 2006; 115:115-22. [PMID: 17065791 DOI: 10.1159/000095230] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Accepted: 02/03/2006] [Indexed: 02/03/2023] Open
Abstract
The Solute Carrier Family 27 Member 1 (SLC27A1) is an evolutionarily conserved protein involved in regulating the long chain fatty acid uptake into cells. It has been shown to be expressed in tissues undergoing rapid fatty acid metabolism such as heart, skeletal muscle and adipose tissues, but no expression is detected in liver. Here we report the molecular characterization of the bovine SLC27A1 gene and draw a comparison with orthologous genes of some monogastric species. The bovine SLC27A1 gene is organized in 13 exons and extends over more than 40 kb of genomic DNA. It codes for a protein of 646 amino acids with a predicted molecular weight of 71 kDa which has 92%, 88% and 88% similarity with the human, mouse and rat SLC27A1 proteins respectively. The bovine SLC27A1 RNA expression was high in heart, testis, nervous tissue and muscle and very low in liver. Surprisingly, adipose tissues showed very low RNA expression levels contrary to the results described for both human and mouse genes. On the other hand, discordances observed between the bovine SLC27A1 RNA and protein expression patterns suggest that complex regulation mechanisms may be involved in determining the final SLC27A1 protein levels in each tissue. Finally, we have identified an alternative transcript generated by exon skipping of exon 3 to 7 which could encode a cytosolic SLC27A1 isoform of approximately 37 kDa.
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Affiliation(s)
- L Ordovás
- Laboratorio de Genética Bioquímica (LAGENBIO), Universidad de Zaragoza, Zaragoza, Spain
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20
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Affiliation(s)
- L Ordovás
- Laboratorio de Genética Bioquímica, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza 50013, Spain.
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21
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Abstract
Hepatic steatosis is a consequence of both obesity and ethanol use. Nonalcoholic steatosis (NASH) resemble alcoholic steatosis and steatohepatitis. Both exhibit increased hepatocellular triglycerides(TG), reflecting an increase in long chain fatty acids (LCFA). LCFA enter cells by both facilitated transport and passive diffusion. A driving force for both is the plasma unbound LCFA concentration ([LCFAu]). In both obese rodents and obese patients, adipocyte LCFA uptake via both facilitated transport and diffusion is increased. However, the LCFA uptake Vmax in hepatocytes is not increased in obese animals. Nevertheless, total LCFA uptake in obese rodents is increased ~3-fold, reflecting increased plasma LCFA concentrations. With advancing obesity, resistance to the antilipolytic effects of insulin results in increased lipolysis within the omental fat depot, a consequent further rise in portal venous LCFA, and an even greater rise in portal [LCFAu]. This causes a further increase in hepatocellular LCFA uptake, increased intracellular generation of reactive oxygen species (ROS), and transition from simple steatosis to NASH. By contrast, in rodent hepatocytes and in human hepatoma cell lines, ethanol up-regulates the LCFA uptake Vmax. Consequently, although plasma LCFA are unaltered, hepatocellular LCFA uptake in ethanol-fed rats is also increased~3-fold, leading to increased ROS generation and evolution of alcoholic hepatitis. Thus, while increased hepatic LCFA uptake contributes to the pathogenesis of both NASH and alcoholic hepatitis,the underlying mechanisms differ. Recognizing these mechanistic differences is important in developing strategies for both prevention and treatment of these conditions.
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Affiliation(s)
- Michael W Bradbury
- Department of Medicine (Division of Liver Disease), Mount Sinai School of Medicine, 1 Gustave L. Levy Place, Box 1039, New York, NY 10029, USA.
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22
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Sauer LA, Dauchy RT, Blask DE, Krause JA, Davidson LK, Dauchy EM, Welham KJ, Coupland K. Conjugated linoleic acid isomers and trans fatty acids inhibit fatty acid transport in hepatoma 7288CTC and inguinal fat pads in Buffalo rats. J Nutr 2004; 134:1989-97. [PMID: 15284388 DOI: 10.1093/jn/134.8.1989] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Conjugated linoleic acid (CLA) and some trans fatty acids (FA) decrease tumor growth and alter tumor and host lipid uptake and storage. The goal of this study was to test the hypothesis that the acute inhibitory effects of CLA isomers and trans FAs on FA transport in tumors and white adipose tissue are mediated via an inhibitory G-protein coupled (GPC), FFA receptor (FFAR). Experiments were performed in hepatoma 7288CTC and inguinal fat pads in Buffalo rats during perfusion in situ. CLA isomers and trans FAs (0.03-0.4 mmol/L, in plasma) were added to the arterial blood, and FA uptake or release was measured by arterial minus venous difference. In hepatoma 7288CTC, the CLA isomers, t10,c12-CLA > (+/-)-9-HODE [13-(S)-hydroxyoctadecadienoic acid] > t9,t11-CLA, and the trans FAs, linolelaidic = vaccenic > elaidic, decreased cAMP content and inhibited FA uptake, 13(S)-HODE release, extracellular signal-regulated kinase p44/p42 phosphorylation, and [(3)H]thymidine incorporation. Other CLA isomers, c9,t11-CLA, 13-(S)-HODE, c9,c11-CLA, and c11,t13-CLA, had no effect. In inguinal fat pads, FA transport was inhibited by t10,c12-CLA = linolelaidic acid > trans vaccenic acid, whereas c9,t11-CLA had no effect. In both hepatoma 7288CTC and inguinal fat pad, addition of either pertussis toxin or 8-Br-cAMP to the arterial blood reversed the inhibitions of FA transport. These results support the idea that an inhibitory GPC FFAR reduces cAMP and controls FA transport by CLA isomers and trans FAs. Ligand activity is conferred by the presence of a trans double bond proximal to the carboxyl group.
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Marotta M, Ferrer-Martnez A, Parnau J, Turini M, Macé K, Gómez Foix AM. Fiber type- and fatty acid composition-dependent effects of high-fat diets on rat muscle triacylglyceride and fatty acid transporter protein-1 content. Metabolism 2004; 53:1032-6. [PMID: 15281014 DOI: 10.1016/j.metabol.2004.03.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Intramuscular triacylglyceride (TAG) is considered an independent marker of insulin resistance in humans. Here, we examined the effect of high-fat diets, based on distinct fatty acid compositions (saturated, monounsaturated or n-6 polyunsaturated), on TAG levels and fatty acid transporter protein (FATP-1) expression in 2 rat muscles that differ in their fiber type, soleus, and gastrocnemius; the relationship to whole body glucose intolerance was also studied. Compared with carbohydrate-fed rats, the groups subjected to any one of the high-fat diets consistently exhibited enhanced body weight gain and adiposity, elevated plasma free fatty acids and TAG in the fed condition, hyperinsulinemia, and glucose intolerance. TAG content was consistently higher in soleus than in gastrocnemius, but was only significantly elevated by the n-6 polyunsaturated-based diet. FATP-1 levels in soleus were double those in gastrocnemius muscle in carbohydrate-fed animals. High-fat diets caused an elevation in FATP-1 protein content in soleus, but a reduction in gastrocnemius. In conclusion, the hyperinsulinemic hyperlipidemic condition upregulates FATP-1 expression in soleus and downregulates that of gastrocnemius. Hypercaloric saturated, monounsaturated, or n-6 polyunsaturated lipid diets cause equivalent whole body insulin resistance in rats, but only an n-6 polyunsaturated acid-based diet triggers intramuscular TAG accumulation.
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Affiliation(s)
- Mario Marotta
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Spain
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24
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Martin GG, Danneberg H, Kumar LS, Atshaves BP, Erol E, Bader M, Schroeder F, Binas B. Decreased liver fatty acid binding capacity and altered liver lipid distribution in mice lacking the liver fatty acid-binding protein gene. J Biol Chem 2003; 278:21429-38. [PMID: 12670956 DOI: 10.1074/jbc.m300287200] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Although liver fatty acid-binding protein (L-FABP) is an important binding site for various hydrophobic ligands in hepatocytes, its in vivo significance is not understood. We have therefore created L-FABP null mice and report here their initial analysis, focusing on the impact of this mutation on hepatic fatty acid binding capacity, lipid composition, and expression of other lipid-binding proteins. Gel-filtered cytosol from L-FABP null liver lacked the main fatty acid binding peak in the fraction that normally comprises both L-FABP and sterol carrier protein-2 (SCP-2). The binding capacity for cis-parinaric acid was decreased >80% in this region. Molar ratios of cholesterol/cholesterol ester, cholesteryl ester/triglyceride, and cholesterol/phospholipid were 2- to 3-fold greater, reflecting up to 3-fold absolute increases in specific lipid classes in the order cholesterol > cholesterol esters > phospholipids. In contrast, the liver pool sizes of nonesterified fatty acids and triglycerides were not altered. However, hepatic deposition of a bolus of intravenously injected [14C]oleate was markedly reduced, showing altered lipid pool turnover. An increase of approximately 75% of soluble SCP-2 but little or no change of other soluble (glutathione S-transferase, albumin) and membrane (fatty acid transport protein, CD36, aspartate aminotransferase, caveolin) fatty acid transporters was measured. These results (i) provide for the first time a quantitative assessment of the contribution of L-FABP to cytosolic fatty acid binding capacity, (ii) establish L-FABP as an important determinant of hepatic lipid composition and turnover, and (iii) suggest that SCP-2 contributes to the accumulation of cholesterol in L-FABP null liver.
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Affiliation(s)
- Gregory G Martin
- Department of Physiology and Pharmacology, College of Veterinary Medicine, Texas A&M University, Raymond Stotzer Parkway, College Station, TX 77843-4467, USA
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25
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Bradbury MW, Berk PD. Cellular uptake of long chain free fatty acids: the structure and function of plasma membrane fatty acid binding protein. Lipobiology. Elsevier; 2003. pp. 47-80. [DOI: 10.1016/s1569-2558(03)33004-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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26
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Brinkmann JFF, Abumrad NA, Ibrahimi A, van der Vusse GJ, Glatz JFC. New insights into long-chain fatty acid uptake by heart muscle: a crucial role for fatty acid translocase/CD36. Biochem J 2002; 367:561-70. [PMID: 12088505 PMCID: PMC1222912 DOI: 10.1042/bj20020747] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2002] [Revised: 06/24/2002] [Accepted: 06/28/2002] [Indexed: 01/30/2023]
Abstract
Long-chain fatty acids are an important source of energy for several cell types, in particular for the heart muscle cell. Three different proteins, fatty acid translocase (FAT)/CD36, fatty acid transport protein and plasma membrane fatty acid binding protein, have been identified as possible membrane fatty acid transporters. Much information has been accumulated recently about the fatty acid transporting function of FAT/CD36. Several experimental models to study the influence of altered FAT/CD36 expression on fatty acid homoeostasis have been identified or developed, and underscore the importance of FAT/CD36 for adequate fatty acid transport. These models include the FAT/CD36 null mouse, the spontaneously hypertensive rat and FAT/CD36-deficient humans. The fatty acid transporting role of FAT/CD36 is further demonstrated in mice overexpressing muscle-specific FAT/CD36, and in transgenic mice generated using a genetic-rescue approach. In addition, a wealth of information has been gathered about the mechanisms that regulate FAT/CD36 gene expression and the presence of functional FAT/CD36 on the plasma membrane. Available data also indicate that FAT/CD36 may have an important role in the aetiology of cardiac disease, especially cardiac hypertrophy and diabetic cardiomyopathy. This review discusses our current knowledge of the three candidate fatty acid transporters, the metabolic consequences of alterations in FAT/CD36 levels in different models, and the mechanisms that have been identified for FAT/CD36 regulation.
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Affiliation(s)
- Joep F F Brinkmann
- Cardiovascular Research Institute Maastricht (CARIM), Department of Physiology, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
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Kondo H, Shimomura I, Kishida K, Kuriyama H, Makino Y, Nishizawa H, Matsuda M, Maeda N, Nagaretani H, Kihara S, Kurachi Y, Nakamura T, Funahashi T, Matsuzawa Y. Human aquaporin adipose (AQPap) gene. Genomic structure, promoter analysis and functional mutation. Eur J Biochem 2002; 269:1814-26. [PMID: 11952783 DOI: 10.1046/j.1432-1033.2002.02821.x] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Aquaporin adipose (AQPap), which we identified from human adipose tissue, is a glycerol channel in adipocyte [Kishida et al. (2000) J. Biol. Chem. 275, 20896-20902]. In the current study, we determined the genomic structure of the human AQPap gene, and identified three AQPap-like genes that resembled (approximately 95%) AQPap, with little expression in human tissues. The AQPap promoter contained a putative peroxisome proliferator response element (PPRE) at -46 to -62, and a putative insulin response element (IRE) at -542/-536. Deletion of the PPRE abolished the pioglitazone-mediated induction of AQPap promoter activity in 3T3-L1 adipocytes. Deletion and single base pair substitution analysis of the IRE abolished the insulin-mediated suppression of the human AQPap gene. Analysis of AQPap sequence in human subjects revealed three missense mutations (R12C, V59L and G264V), and two silent mutations (A103A and G250G). The cRNA injection of the missense mutants into Xenopus oocytes revealed the absence of the activity to transport glycerol and water in the AQPap-G264V protein. In the subject homozygous for AQPap-G264V, exercise-induced increase in plasma glycerol was not observed in spite of the increased plasma noradrenaline. We suggest that AQPap is responsible for the increase of plasma glycerol during exercise in humans.
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Affiliation(s)
- Hidehiko Kondo
- Department of Internal Medicine and Molecular Science, Graduate School of Medicine, Osaka University, Yamadaoka, Suita, Japan
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Bleck B, Buhlmann C, Hohoff C, Müller M, Börchers T, Spener F. Inversely related expression of epidermal- and heart-type fatty acid binding proteins during myogenic differentiation of C2C12 myoblasts. EUR J LIPID SCI TECH 2002. [DOI: 10.1002/1438-9312(200202)104:2<88::aid-ejlt88>3.0.co;2-g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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29
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Kishida K, Shimomura I, Kondo H, Kuriyama H, Makino Y, Nishizawa H, Maeda N, Matsuda M, Ouchi N, Kihara S, Kurachi Y, Funahashi T, Matsuzawa Y. Genomic structure and insulin-mediated repression of the aquaporin adipose (AQPap), adipose-specific glycerol channel. J Biol Chem 2001; 276:36251-60. [PMID: 11457862 DOI: 10.1074/jbc.m106040200] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aquaporin adipose (AQPap) is a putative glycerol channel in adipocytes (Kishida, K., Kuriyama, H., Funahashi, T., Shimomura, I., Kihara, S., Ouchi, N., Nishida, M., Nishizawa, H., Matsuda, M., Takahashi, M., Hotta, K., Nakamura, T., Yamashita, S., Tochino, Y., and Matsuzawa, Y. (2000) J. Biol. Chem. 275, 20896-20902). In the current study, we examined the genomic structure of the mouse AQPap gene and its regulation by insulin. The mouse AQPap gene spanned 12 kilobase pairs in chromosome 4 and consisted of 8 exons and 7 introns. The first two exons, designated exon 1 and exon 1', are alternatively spliced to common exon 2, and thus the AQPap gene possessed two potential promoters. The exon 1-derived transcript is dominant in both adipose tissues and adipocytes on the basis of RNase protection assay and promoter analysis. The mRNA increased after fasting and decreased with refeeding. Insulin deficiency generated by streptozotocin enhanced the mRNA in adipose tissue. Insulin down-regulated AQPap mRNA in 3T3-L1 adipocytes. The AQPap promoter contained heptanucleotide sequences, TGTTTTT at -443/-437, similar to the insulin-response element identified previously in the promoters of insulin-repressed genes. Deletion and single base pair substitution analysis of the promoter revealed that these sequences were required for insulin-mediated repression of AQPap gene transcription. The phosphatidylinositol 3-kinase pathway was involved in this inhibition. We conclude that insulin represses the transcription of AQPap gene via insulin response element in its promoter. Sustained up-regulation of AQPap mRNA in adipose tissue in the insulin-resistant condition may disturb glucose homeostasis by increasing plasma glycerol.
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MESH Headings
- 3T3 Cells
- Adipocytes/metabolism
- Amino Acid Sequence
- Animals
- Aquaporins/chemistry
- Aquaporins/genetics
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- Cattle
- Chromosome Mapping
- DNA, Complementary/metabolism
- Diabetes Mellitus, Experimental
- Dose-Response Relationship, Drug
- Down-Regulation
- Exons
- Gene Deletion
- Gene Expression Regulation
- Glycerol/metabolism
- Insulin/metabolism
- Insulin/pharmacology
- Introns
- Luciferases/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred ICR
- Models, Genetic
- Molecular Sequence Data
- Phosphatidylinositol 3-Kinases/metabolism
- Point Mutation
- Promoter Regions, Genetic
- RNA, Messenger/metabolism
- Radiation Hybrid Mapping
- Tissue Distribution
- Transfection
- Up-Regulation
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Affiliation(s)
- K Kishida
- Department of Internal Medicine and Molecular Science, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita 565-0871, Japan
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30
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Sauer LA, Dauchy RT, Blask DE. Polyunsaturated fatty acids, melatonin, and cancer prevention 1 1Abbreviations: 13-HODE, 13-hydroxyoctadecadienoic acid; NDGA, nordihydroguaiaretic acid; EGF, epidermal growth factor; EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; 8-Br-cAMP, 8-bromo-cyclic adenosine monophosphate; FATP, fatty acid transport protein; cAMP, cyclic adenosine monophosphate; TGFα, tumor growth factor alpha; MAPK, mitogen-activated protein kinase; and FAT, fatty acid translocase. Biochem Pharmacol 2001; 61:1455-62. [PMID: 11377374 DOI: 10.1016/s0006-2952(01)00634-7] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Many nutritional, hormonal, and environmental factors affect carcinogenesis and growth of established tumors in rodents. In some cases, these factors may either enhance or attenuate the neoplastic process. Recent experiments performed in our laboratory using tissue-isolated rat hepatoma 7288CTC in vivo or during perfusion in situ have demonstrated new interactions among four of these factors. Two agents, dietary linoleic acid (C18:2n6) and "light at night," enhanced tumor growth, and two others, melatonin and n3 fatty acids, attenuated growth. Linoleic acid stimulated tumor growth because it is converted by hepatoma 7288CTC to the mitogen, 13-hydroxyoctadecadienoic acid (13-HODE). Melatonin, the neurohormone synthesized and secreted at night by the pineal gland, and dietary n3 fatty acids are potent antitumor agents. Both inhibited tumor linoleic acid uptake and 13-HODE formation. Artificial light, specifically "light at night," increased tumor growth because it suppressed melatonin synthesis and enhanced 13-HODE formation. Melatonin and n3 fatty acids acted via similar or identical G(i) protein-coupled signal transduction pathways, except that melatonin receptors and putative n3 fatty acid receptors were used. The results link the four factors in a common mechanism and provide new insights into the roles of dietary n6 and n3 polyunsaturated fatty acid intake, "light at night," and melatonin in cancer prevention in humans.
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Affiliation(s)
- L A Sauer
- Bassett Research Institute, The Mary Imogene Bassett Hospital, Cooperstown, NY 13326, USA.
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31
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Herrmann T, Buchkremer F, Gosch I, Hall AM, Bernlohr DA, Stremmel W. Mouse fatty acid transport protein 4 (FATP4): characterization of the gene and functional assessment as a very long chain acyl-CoA synthetase. Gene 2001; 270:31-40. [PMID: 11404000 DOI: 10.1016/s0378-1119(01)00489-9] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
FATP4 (SLC27A4) is a member of the fatty acid transport protein (FATP) family, a group of evolutionarily conserved proteins that are involved in cellular uptake and metabolism of long and very long chain fatty acids. We cloned and characterized the murine FATP4 gene and its cDNA. From database analysis we identified the human FATP4 genomic sequence. The FATP4 gene was assigned to mouse chromosome 2 band B, syntenic to the region 9q34 encompassing the human gene. The open reading frame was determined to be 1929 bp in length, encoding a polypeptide of 643 amino acids. Within the coding region, the exon-intron structures of the murine FATP4 gene and its human counterpart are identical, revealing a high similarity to the FATP1 gene. The overall amino acid identity between the deduced murine and human FATP4 polypeptides is 92.2%, and between the murine FATP1 and FATP4 polypeptides is 60.3%. Northern analysis showed that FATP4 mRNA was expressed most abundantly in small intestine, brain, kidney, liver, skin and heart. Transfection of FATP4 cDNA into COS1 cells resulted in a 2-fold increase in palmitoyl-CoA synthetase (C16:0) and a 5-fold increase in lignoceroyl-CoA synthetase (C24:0) activity from membrane extracts, indicating that the FATP4 gene encodes an acyl-CoA synthetase with substrate specificity biased towards very long chain fatty acids.
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Affiliation(s)
- T Herrmann
- Department of Internal Medicine IV, University of Heidelberg, Bergheimer Strasse 58, 69115, Heidelberg, Germany.
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Abstract
Muscle plays a major role in metabolism. Thus it is a major glucose-utilizing tissue in the absorptive state, and changes in muscle insulin-stimulated glucose uptake alter whole-body glucose disposal. In some conditions, muscle preferentially uses lipid substrates, such as fatty acids or ketone bodies. Furthermore, muscle is the main reservoir of amino acids and protein. The activity of many different plasma membrane transporters, such as glucose carriers and transporters of carnitine, creatine and amino acids, play a crucial role in muscle metabolism by catalysing the influx or the efflux of substrates across the cell surface. In some cases, the membrane transport process is subjected to intense regulatory control and may become a potential pharmacological target, as is the case with the glucose transporter GLUT4. The goal of this review is the molecular characterization of muscle membrane transporter proteins, as well as the analysis of their possible regulatory role.
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Affiliation(s)
- A Zorzano
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, 08028 Barcelona, Spain.
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Abstract
Lipophilic molecules can passively diffuse across cell membranes, a process that is driven by the concentration gradient, by availability of acceptors to facilitate desorption from the bilayer, and by cellular metabolism. However, evidence has accumulated that supports the existence of specialized, protein-facilitated membrane transport systems for many lipophilic molecules. This has generated considerable debate regarding why such systems need to exist. The present review summarizes recent developments related to the membrane transport systems for cholesterol and fatty acids, which have been shown to involve structurally related proteins. General similarities of the cholesterol and fatty acid systems to other lipid transport systems (briefly discussed in the Introduction section) are highlighted in the Conclusion section. The overall aim of the present review is to illustrate why lipid transporters are needed in vivo, and how they accomplish specific functions that can not be met by lipid diffusion alone.
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Affiliation(s)
- N A Abumrad
- Department of Physiology and Biophysics, State University of New York at Stony Brook, 11794-8661, USA.
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Martin G, Nemoto M, Gelman L, Geffroy S, Najib J, Fruchart JC, Roevens P, de Martinville B, Deeb S, Auwerx J. The human fatty acid transport protein-1 (SLC27A1; FATP-1) cDNA and gene: organization, chromosomal localization, and expression. Genomics 2000; 66:296-304. [PMID: 10873384 DOI: 10.1006/geno.2000.6191] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Uptake of fatty acids into cells is a controlled process in part regulated by fatty acid transport proteins (FATPs), which facilitate the transport of fatty acids across the cell membrane. In this study the structure of the human FATP-1 (HGMW-approved symbol SLC27A1) cDNA and gene was determined, and the expression of its mRNA in human was characterized. Muscle and adipose tissue have the highest levels of FATP-1 mRNA, small intestine has intermediate levels, and FATP-1 mRNA is barely detectable in liver. The human FATP-1 gene has 12 exons and extends over more than 13 kb of genomic DNA. The FATP gene maps to chromosome 19p13.1 by fluorescence in situ hybridization, a region previously suggested to be implicated in the determination of small dense low-density lipoprotein (LDL). Knowledge of the gene structure and chromosomal localization will allow screening for FATP mutations in humans with metabolic disorders, whereas knowledge of its expression pattern and factors regulating its expression could be of importance in understanding its biology.
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Affiliation(s)
- G Martin
- Département d'Athérosclérose, INSERM U 325, Lille, F-59019, France
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Affiliation(s)
- B I Frohnert
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 140 Gortner Laboratory, 1479 Gortner Avenue, Saint Paul 55108-1022, USA
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Abstract
The primary sequence of the murine fatty acid transport protein (FATP1) is very similar to the multigene family of very long chain (C20-C26) acyl-CoA synthetases. To determine if FATP1 is a long chain acyl coenzyme A synthetase, FATP1-Myc/His fusion protein was expressed in COS1 cells, and its enzymatic activity was analyzed. In addition, mutations were generated in two domains conserved in acyl-CoA synthetases: a 6- amino acid substitution into the putative active site (amino acids 249-254) generating mutant M1 and a 59-amino acid deletion into a conserved C-terminal domain (amino acids 464-523) generating mutant M2. Immunolocalization revealed that the FATP1-Myc/His forms were distributed between the COS1 cell plasma membrane and intracellular membranes. COS1 cells expressing wild type FATP1-Myc/His exhibited a 3-fold increase in the ratio of lignoceroyl-CoA synthetase activity (C24:0) to palmitoyl-CoA synthetase activity (C16:0), characteristic of very long chain acyl-CoA synthetases, whereas both mutant M1 and M2 were catalytically inactive. Detergent-solubilized FATP1-Myc/His was partially purified using nickel-based affinity chromatography and demonstrated a 10-fold increase in very long chain acyl-CoA specific activity (C24:0/C16:0). These results indicate that FATP1 is a very long chain acyl-CoA synthetase and suggest that a potential mechanism for facilitating mammalian fatty acid uptake is via esterification coupled influx.
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Affiliation(s)
- N R Coe
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, Minnesota 55108, USA
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Abstract
The peroxisome proliferator-activated receptor-gamma (PPARgamma) is a nuclear receptor that controls the expression of a large array of genes involved in adipocyte differentiation, lipid storage and insulin sensitization. PPARgamma is bound and activated by prostaglandin J2 and fatty acid derivatives, which are its natural ligands. In addition, thiazolidinediones and nonsteroidal anti-inflammatory drugs are synthetic ligands and agonists of this receptor. Several studies have recently shown that this nuclear receptor has a role expanding beyond metabolism (diabetes and obesity) with functions in cell cycle control, carcinogenesis, inflammation and atherosclerosis. This review addresses the role of PPARgamma in these processes.
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Affiliation(s)
- S Rocchi
- Institute of Genetics and Molecular and Cellular Biology, Illkirch, France
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Frohnert BI, Hui TY, Bernlohr DA. Identification of a functional peroxisome proliferator-responsive element in the murine fatty acid transport protein gene. J Biol Chem 1999; 274:3970-7. [PMID: 9933587 DOI: 10.1074/jbc.274.7.3970] [Citation(s) in RCA: 193] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Fatty acid transport protein (FATP), a plasma membrane protein implicated in controlling adipocyte transmembrane fatty acid flux, is up-regulated as a consequence of adipocyte differentiation and down-regulated by insulin. Based upon the sequence of the FATP gene upstream region (Hui, T. Y., Frohnert, B. I., Smith, A. J., Schaffer, J. A., and Bernlohr, D. A. (1998) J. Biol. Chem. 273, 27420-27429) a putative peroxisome proliferator-activated receptor response element (PPRE) is present from -458 to -474. To determine whether the FATP PPRE was functional, and responded to lipid activators, transient transfection of FATP-luciferase reporter constructs into CV-1 and 3T3-L1 cells was carried out. In CV-1 cells, FATP-luciferase activity was up-regulated 4- and 5.5-fold, respectively, by PPARalpha and PPARgamma in the presence of their respective activators in a PPRE-dependent mechanism. PPARdelta, however, was unable to mediate transcriptional activation under any condition. In 3T3-L1 cells, the PPRE conferred a small but significant increase in expression in preadipocytes, as well as a more robust up-regulation of FATP expression in adipocytes. Furthermore, the PPRE conferred the ability for luciferase expression to be up-regulated by activators of both PPARgamma and retinoid X receptor alpha (RXRalpha) in a synergistic manner. PPARalpha and PPARdelta activators did not up-regulate FATP expression in 3T3-L1 adipocytes, however, suggesting that these two subtypes do not play a significant role in differentiation-dependent activation in fat cells. Electromobility shift assays showed that all three PPAR subtypes were able to bind specifically to the PPRE as heterodimers with RXRalpha. Nuclear extracts from 3T3-L1 adipocytes also showed a specific gel-shift complex with the FATP PPRE. To correlate the expression of FATP to its physiological function, treatment of 3T3-L1 adipocytes with PPARgamma and RXRalpha activators resulted in an increased uptake of oleate. Moreover, linoleic acid, a physiological ligand, up-regulated FATP expression 2-fold in a PPRE-dependent manner. These results demonstrate that the FATP gene possesses a functional PPRE and is up-regulated by activators of PPARalpha and PPARgamma, thereby linking the activity of the protein to the expression of its gene. Moreover, these results have implications for the mechanism by which certain PPARgamma activators such as the antidiabetic thiazolidinedione drugs affect adipose lipid metabolism.
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Affiliation(s)
- B I Frohnert
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, Minnesota 55108, USA
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