301
|
D’Aquila T, Sirohi D, Grabowski JM, Hedrick VE, Paul LN, Greenberg AS, Kuhn RJ, Buhman KK. Characterization of the proteome of cytoplasmic lipid droplets in mouse enterocytes after a dietary fat challenge. PLoS One 2015; 10:e0126823. [PMID: 25992653 PMCID: PMC4436333 DOI: 10.1371/journal.pone.0126823] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 04/08/2015] [Indexed: 01/23/2023] Open
Abstract
Dietary fat absorption by the small intestine is a multistep process that regulates the uptake and delivery of essential nutrients and energy. One step of this process is the temporary storage of dietary fat in cytoplasmic lipid droplets (CLDs). The storage and mobilization of dietary fat is thought to be regulated by proteins that associate with the CLD; however, mechanistic details of this process are currently unknown. In this study we analyzed the proteome of CLDs isolated from enterocytes harvested from the small intestine of mice following a dietary fat challenge. In this analysis we identified 181 proteins associated with the CLD fraction, of which 37 are associated with known lipid related metabolic pathways. We confirmed the localization of several of these proteins on or around the CLD through confocal and electron microscopy, including perilipin 3, apolipoprotein A-IV, and acyl-CoA synthetase long-chain family member 5. The identification of the enterocyte CLD proteome provides new insight into potential regulators of CLD metabolism and the process of dietary fat absorption.
Collapse
Affiliation(s)
- Theresa D’Aquila
- Department of Nutrition Science, Purdue University, West Lafayette, Indiana, United States of America
| | - Devika Sirohi
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
| | - Jeffrey M. Grabowski
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
- Department of Entomology, Purdue University, West Lafayette, Indiana, United States of America
| | - Victoria E. Hedrick
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
| | - Lake N. Paul
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
| | - Andrew S. Greenberg
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, United States of America
| | - Richard J. Kuhn
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
| | - Kimberly K. Buhman
- Department of Nutrition Science, Purdue University, West Lafayette, Indiana, United States of America
- * E-mail:
| |
Collapse
|
302
|
Hofer P, Boeszoermenyi A, Jaeger D, Feiler U, Arthanari H, Mayer N, Zehender F, Rechberger G, Oberer M, Zimmermann R, Lass A, Haemmerle G, Breinbauer R, Zechner R, Preiss-Landl K. Fatty Acid-binding Proteins Interact with Comparative Gene Identification-58 Linking Lipolysis with Lipid Ligand Shuttling. J Biol Chem 2015; 290:18438-53. [PMID: 25953897 PMCID: PMC4513104 DOI: 10.1074/jbc.m114.628958] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Indexed: 12/18/2022] Open
Abstract
The coordinated breakdown of intracellular triglyceride (TG) stores requires the exquisitely regulated interaction of lipolytic enzymes with regulatory, accessory, and scaffolding proteins. Together they form a dynamic multiprotein network designated as the “lipolysome.” Adipose triglyceride lipase (Atgl) catalyzes the initiating step of TG hydrolysis and requires comparative gene identification-58 (Cgi-58) as a potent activator of enzyme activity. Here, we identify adipocyte-type fatty acid-binding protein (A-Fabp) and other members of the fatty acid-binding protein (Fabp) family as interaction partners of Cgi-58. Co-immunoprecipitation, microscale thermophoresis, and solid phase assays proved direct protein/protein interaction between A-Fabp and Cgi-58. Using nuclear magnetic resonance titration experiments and site-directed mutagenesis, we located a potential contact region on A-Fabp. In functional terms, A-Fabp stimulates Atgl-catalyzed TG hydrolysis in a Cgi-58-dependent manner. Additionally, transcriptional transactivation assays with a luciferase reporter system revealed that Fabps enhance the ability of Atgl/Cgi-58-mediated lipolysis to induce the activity of peroxisome proliferator-activated receptors. Our studies identify Fabps as crucial structural and functional components of the lipolysome.
Collapse
Affiliation(s)
- Peter Hofer
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Andras Boeszoermenyi
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Doris Jaeger
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Ursula Feiler
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Haribabu Arthanari
- the Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
| | - Nicole Mayer
- the Institute of Organic Chemistry, Graz University of Technology, 8010 Graz, Austria, and
| | | | - Gerald Rechberger
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Monika Oberer
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Robert Zimmermann
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Achim Lass
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Guenter Haemmerle
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - Rolf Breinbauer
- the Institute of Organic Chemistry, Graz University of Technology, 8010 Graz, Austria, and
| | - Rudolf Zechner
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria,
| | - Karina Preiss-Landl
- From the Institute of Molecular Biosciences, University of Graz, NAWI Graz, 8010 Graz, Austria,
| |
Collapse
|
303
|
Aimo L, Liechti R, Hyka-Nouspikel N, Niknejad A, Gleizes A, Götz L, Kuznetsov D, David FPA, van der Goot FG, Riezman H, Bougueleret L, Xenarios I, Bridge A. The SwissLipids knowledgebase for lipid biology. Bioinformatics 2015; 31:2860-6. [PMID: 25943471 PMCID: PMC4547616 DOI: 10.1093/bioinformatics/btv285] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 04/29/2015] [Indexed: 12/20/2022] Open
Abstract
MOTIVATION Lipids are a large and diverse group of biological molecules with roles in membrane formation, energy storage and signaling. Cellular lipidomes may contain tens of thousands of structures, a staggering degree of complexity whose significance is not yet fully understood. High-throughput mass spectrometry-based platforms provide a means to study this complexity, but the interpretation of lipidomic data and its integration with prior knowledge of lipid biology suffers from a lack of appropriate tools to manage the data and extract knowledge from it. RESULTS To facilitate the description and exploration of lipidomic data and its integration with prior biological knowledge, we have developed a knowledge resource for lipids and their biology-SwissLipids. SwissLipids provides curated knowledge of lipid structures and metabolism which is used to generate an in silico library of feasible lipid structures. These are arranged in a hierarchical classification that links mass spectrometry analytical outputs to all possible lipid structures, metabolic reactions and enzymes. SwissLipids provides a reference namespace for lipidomic data publication, data exploration and hypothesis generation. The current version of SwissLipids includes over 244 000 known and theoretically possible lipid structures, over 800 proteins, and curated links to published knowledge from over 620 peer-reviewed publications. We are continually updating the SwissLipids hierarchy with new lipid categories and new expert curated knowledge. AVAILABILITY SwissLipids is freely available at http://www.swisslipids.org/. CONTACT alan.bridge@isb-sib.ch SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Lucila Aimo
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - Robin Liechti
- Vital-IT, SIB Swiss Institute of Bioinformatics, Quartier Sorge, Bâtiment Génopode, CH-1015 Lausanne, Switzerland
| | - Nevila Hyka-Nouspikel
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - Anne Niknejad
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - Anne Gleizes
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - Lou Götz
- Vital-IT, SIB Swiss Institute of Bioinformatics, Quartier Sorge, Bâtiment Génopode, CH-1015 Lausanne, Switzerland
| | - Dmitry Kuznetsov
- Vital-IT, SIB Swiss Institute of Bioinformatics, Quartier Sorge, Bâtiment Génopode, CH-1015 Lausanne, Switzerland
| | - Fabrice P A David
- Bioinformatics and Biostatistics Core Facility, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland, SIB Swiss Institute of Bioinformatics, CH-1015 Lausanne, Switzerland
| | - F Gisou van der Goot
- Global Health Institute, École Polytechnique Fédérale de Lausanne, Station 19, CH-1015 Lausanne, Switzerland
| | - Howard Riezman
- Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland, Switzerland National Centre of Competence in Research "Chemical Biology", University of Geneva, CH-1211 Geneva, Switzerland and
| | - Lydie Bougueleret
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - Ioannis Xenarios
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland, Vital-IT, SIB Swiss Institute of Bioinformatics, Quartier Sorge, Bâtiment Génopode, CH-1015 Lausanne, Switzerland, Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland, Centre for Integrative Genomics, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Alan Bridge
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| |
Collapse
|
304
|
Louis C, Perdaens L, Suciu S, Tavoni SK, Crocker DE, Debier C. Mobilisation of blubber fatty acids of northern elephant seal pups (Mirounga angustirostris) during the post-weaning fast. Comp Biochem Physiol A Mol Integr Physiol 2015; 183:78-86. [DOI: 10.1016/j.cbpa.2015.01.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 12/23/2014] [Accepted: 01/15/2015] [Indexed: 11/26/2022]
|
305
|
Abstract
Adipose tissue is a complex, multicellular organ that profoundly influences the function of nearly all other organ systems through its diverse metabolite and adipokine secretome. Adipocytes are the primary cell type of adipose tissue and play a key role in maintaining energy homeostasis. The efficiency with which adipose tissue responds to whole-body energetic demands reflects the ability of adipocytes to adapt to an altered nutrient environment, and has profound systemic implications. Deciphering adipocyte cell biology is an important component of understanding how the aberrant physiology of expanding adipose tissue contributes to the metabolic dysregulation associated with obesity.
Collapse
Affiliation(s)
- Joseph M Rutkowski
- Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jennifer H Stern
- Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390 Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| |
Collapse
|
306
|
DiStefano MT, Danai LV, Roth Flach RJ, Chawla A, Pedersen DJ, Guilherme A, Czech MP. The Lipid Droplet Protein Hypoxia-inducible Gene 2 Promotes Hepatic Triglyceride Deposition by Inhibiting Lipolysis. J Biol Chem 2015; 290:15175-84. [PMID: 25922078 DOI: 10.1074/jbc.m115.650184] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Indexed: 12/22/2022] Open
Abstract
The liver is a major site of glucose, fatty acid, and triglyceride (TG) synthesis and serves as a major regulator of whole body nutrient homeostasis. Chronic exposure of humans or rodents to high-calorie diets promotes non-alcoholic fatty liver disease, characterized by neutral lipid accumulation in lipid droplets (LD) of hepatocytes. Here we show that the LD protein hypoxia-inducible gene 2 (Hig2/Hilpda) functions to enhance lipid accumulation in hepatocytes by attenuating TG hydrolysis. Hig2 expression increased in livers of mice on a high-fat diet and during fasting, two states associated with enhanced hepatic TG content. Hig2 expressed in primary mouse hepatocytes localized to LDs and promoted LD TG deposition in the presence of oleate. Conversely, tamoxifen-inducible Hig2 deletion reduced both TG content and LD size in primary hepatocytes from mice harboring floxed alleles of Hig2 and a cre/ERT2 transgene controlled by the ubiquitin C promoter. Hepatic TG was also decreased by liver-specific deletion of Hig2 in mice with floxed Hig2 expressing cre controlled by the albumin promoter. Importantly, we demonstrate that Hig2-deficient hepatocytes exhibit increased TG lipolysis, TG turnover, and fatty acid oxidation as compared with controls. Interestingly, mice with liver-specific Hig2 deletion also display improved glucose tolerance. Taken together, these data indicate that Hig2 plays a major role in promoting lipid sequestration within LDs in mouse hepatocytes through a mechanism that impairs TG degradation.
Collapse
Affiliation(s)
- Marina T DiStefano
- From the Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Laura V Danai
- From the Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Rachel J Roth Flach
- From the Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Anil Chawla
- From the Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - David J Pedersen
- From the Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Adilson Guilherme
- From the Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Michael P Czech
- From the Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| |
Collapse
|
307
|
Guijas C, Rodríguez JP, Rubio JM, Balboa MA, Balsinde J. Phospholipase A2 regulation of lipid droplet formation. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1841:1661-71. [PMID: 25450448 DOI: 10.1016/j.bbalip.2014.10.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 10/02/2014] [Accepted: 10/14/2014] [Indexed: 02/07/2023]
Abstract
The classical regard of lipid droplets as mere static energy-storage organelles has evolved dramatically. Nowadays these organelles are known to participate in key processes of cell homeostasis, and their abnormal regulation is linked to several disorders including metabolic diseases (diabetes, obesity, atherosclerosis or hepatic steatosis), inflammatory responses in leukocytes, cancer development and neurodegenerative diseases. Hence, the importance of unraveling the cell mechanisms controlling lipid droplet biosynthesis, homeostasis and degradation seems evident Phospholipase A2s, a family of enzymes whose common feature is to hydrolyze the fatty acid present at the sn-2 position of phospholipids, play pivotal roles in cell signaling and inflammation. These enzymes have recently emerged as key regulators of lipid droplet homeostasis, regulating their formation at different levels. This review summarizes recent results on the roles that various phospholipase A2 forms play in the regulation of lipid droplet biogenesis under different conditions. These roles expand the already wide range of functions that these enzymes play in cell physiology and pathophysiology.
Collapse
|
308
|
Das SK, Stadelmeyer E, Schauer S, Schwarz A, Strohmaier H, Claudel T, Zechner R, Hoefler G, Vesely PW. Micro RNA-124a regulates lipolysis via adipose triglyceride lipase and comparative gene identification 58. Int J Mol Sci 2015; 16:8555-68. [PMID: 25894224 PMCID: PMC4425096 DOI: 10.3390/ijms16048555] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 01/14/2023] Open
Abstract
Lipolysis is the biochemical pathway responsible for the catabolism of cellular triacylglycerol (TG). Lipolytic TG breakdown is a central metabolic process leading to the generation of free fatty acids (FA) and glycerol, thereby regulating lipid, as well as energy homeostasis. The precise tuning of lipolysis is imperative to prevent lipotoxicity, obesity, diabetes and other related metabolic disorders. Here, we present our finding that miR-124a attenuates RNA and protein expression of the major TG hydrolase, adipose triglyceride lipase (ATGL/PNPLA2) and its co-activator comparative gene identification 58 (CGI-58/ABHD5). Ectopic expression of miR-124a in adipocytes leads to reduced lipolysis and increased cellular TG accumulation. This phenotype, however, can be rescued by overexpression of truncated Atgl lacking its 3'UTR, which harbors the identified miR-124a target site. In addition, we observe a strong negative correlation between miR-124a and Atgl expression in various murine tissues. Moreover, miR-124a regulates the expression of Atgl and Cgi-58 in murine white adipose tissue during fasting as well as the expression of Atgl in murine liver, during fasting and re-feeding. Together, these results point to an instrumental role of miR-124a in the regulation of TG catabolism. Therefore, we suggest that miR-124a may be involved in the regulation of several cellular and organismal metabolic parameters, including lipid storage and plasma FA concentration.
Collapse
Affiliation(s)
- Suman K Das
- Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria.
| | - Elke Stadelmeyer
- Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria.
| | - Silvia Schauer
- Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria.
| | - Anna Schwarz
- Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria.
| | - Heimo Strohmaier
- Center for Medical Research, Medical University of Graz, Stiftingtalstrasse 24, 8010 Graz, Austria.
| | - Thiery Claudel
- Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
| | - Rudolf Zechner
- Institute of Molecular Biosciences, Karl Franzens University of Graz, Heinrichstraße 31, 8010 Graz, Austria.
| | - Gerald Hoefler
- Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria.
| | - Paul W Vesely
- Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria.
- Institute of Molecular Biosciences, Karl Franzens University of Graz, Heinrichstraße 31, 8010 Graz, Austria.
| |
Collapse
|
309
|
Jędrkiewicz R, Kupska M, Głowacz A, Gromadzka J, Namieśnik J. 3-MCPD: A Worldwide Problem of Food Chemistry. Crit Rev Food Sci Nutr 2015; 56:2268-77. [DOI: 10.1080/10408398.2013.829414] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
310
|
Ramos SV, Turnbull PC, MacPherson REK, LeBlanc PJ, Ward WE, Peters SJ. Changes in mitochondrial perilipin 3 and perilipin 5 protein content in rat skeletal muscle following endurance training and acute stimulated contraction. Exp Physiol 2015; 100:450-62. [PMID: 25663294 DOI: 10.1113/expphysiol.2014.084434] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 01/27/2015] [Indexed: 01/15/2023]
Abstract
NEW FINDINGS What is the central question of this study? The aim was to determine whether mitochondrial protein content of perilipin 3 (PLIN3) and perilipin 5 (PLIN5) is increased following endurance training and whether mitochondrial PLIN5 protein is increased to a greater extent in endurance-trained rats when compared with sedentary rats following acute contraction. What is the main finding and its importance? Mitochondrial PLIN3 but not PLIN5 protein was increased in endurance-trained compared with sedentary rats, suggesting a mitochondrial role for PLIN3 due to chronic exercise. Contrary to our hypothesis, acute mitochondrial PLIN5 protein was similar in both sedentary and endurance-trained rats. Endurance training results in an increased association between skeletal muscle lipid droplets and mitochondria. This association is likely to be important for the expected increase in intramuscular fatty acid oxidation that occurs with endurance training. The perilipin family of lipid droplet proteins, PLIN(2-5), are thought to play a role in skeletal muscle lipolysis. Recently, results from our laboratory demonstrated that skeletal muscle mitochondria contain PLIN3 and PLIN5 protein. Furthermore, 30 min of stimulated contraction induces an increased mitochondrial PLIN5 content. To determine whether mitochondrial content of PLIN3 and PLIN5 is altered with endurance training, Sprague-Dawley rats were randomized into sedentary or endurance-trained groups for 8 weeks of treadmill running followed by an acute (30 min) sciatic nerve stimulation to induce lipolysis. Mitochondrial PLIN3 protein was ∼1.5-fold higher in red gastrocnemius of endurance-trained rats compared with sedentary animals, with no change in mitochondrial PLIN5 protein. In addition, there was an increase in plantaris intramuscular lipid storage. Acute electrically stimulated contraction in red gastrocnemius from sedentary and endurance-trained rats resulted in a similar increase of mitochondrial PLIN5 between these two groups, with no net change in PLIN3 in either group. Plantaris intramuscular lipid content decreased to a similar extent in sedentary and endurance-trained rats. These results suggest that while total mitochondrial PLIN5 content is not altered by endurance training, PLIN5 does have an acute role in the mitochondrial fraction during muscle contraction. Conversely, mitochondrial PLIN3 does not change acutely with muscle contraction, but PLIN3 content was increased following endurance training, indicating a role in chronic adaptations of skeletal muscle.
Collapse
Affiliation(s)
- S V Ramos
- Center for Bone and Muscle Health, Brock University, St Catharines, Ontario, Canada; Department of Kinesiology, Brock University, St Catharines, Ontario, Canada
| | | | | | | | | | | |
Collapse
|
311
|
Mayer N, Schweiger M, Melcher MC, Fledelius C, Zechner R, Zimmermann R, Breinbauer R. Structure-activity studies in the development of a hydrazone based inhibitor of adipose-triglyceride lipase (ATGL). Bioorg Med Chem 2015; 23:2904-16. [PMID: 25778769 PMCID: PMC4457358 DOI: 10.1016/j.bmc.2015.02.051] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 02/24/2015] [Accepted: 02/25/2015] [Indexed: 11/07/2022]
Abstract
Adipose triglyceride lipase (ATGL) catalyzes the degradation of cellular triacylglycerol stores and strongly determines the concentration of circulating fatty acids (FAs). High serum FA levels are causally linked to the development of insulin resistance and impaired glucose tolerance, which eventually progresses to overt type 2 diabetes. ATGL-specific inhibitors could be used to lower circulating FAs, which can counteract the development of insulin resistance. In this article, we report about structure–activity relationship (SAR) studies of small molecule inhibitors of ATGL based on a hydrazone chemotype. The SAR indicated that the binding pocket of ATGL requests rather linear compounds without bulky substituents. The best inhibitor showed an IC50 = 10 μM in an assay with COS7-cell lysate overexpressing murine ATGL.
Collapse
Affiliation(s)
- Nicole Mayer
- Institute of Organic Chemistry, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
| | - Martina Schweiger
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, A-8010 Graz, Austria
| | | | | | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, A-8010 Graz, Austria
| | - Robert Zimmermann
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, A-8010 Graz, Austria.
| | - Rolf Breinbauer
- Institute of Organic Chemistry, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria.
| |
Collapse
|
312
|
Stelmanska E, Szrok S, Swierczynski J. Progesterone-induced down-regulation of hormone sensitive lipase (Lipe) and up-regulation of G0/G1 switch 2 (G0s2) genes expression in inguinal adipose tissue of female rats is reflected by diminished rate of lipolysis. J Steroid Biochem Mol Biol 2015; 147:31-9. [PMID: 25448749 DOI: 10.1016/j.jsbmb.2014.11.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 11/17/2014] [Accepted: 11/18/2014] [Indexed: 11/23/2022]
Abstract
Decreased lipolytic activity in adipose tissue may be one of the reasons behind excess accumulation of body fat during pregnancy. The aim of this study was to analyze the effect of progesterone on the expression of: (a) Lipe (encoding hormone-sensitive lipase, HSL), (b) Pnpla2 (encoding adipose triglyceride lipase, ATGL), (c) abhydrolase domain containing 5 (Abhd5), and (d) G0/G1 switch 2 (G0s2) genes in white adipose tissue (WAT), as potential targets for progesterone action during the course of pregnancy. Administration of progesterone to female rats, which was reflected by approximately 2.5-fold increase in circulating progesterone concentration, is associated with a decrease in Lipe gene expression in the inguinal WAT. The expression of Pnpla2 gene in all main fat depots of females and males remained unchanged after progesterone administration. Administration of progesterone resulted in an increase in the expression of Abhd5 gene (whose product increases ATGL activity) and G0s2 gene (whose product decreases ATGL activity) in the inguinal WAT of female rats. Mifepristone, a selective antagonist of progesterone receptor, abolished the effect of progesterone on Lipe, Abhd5 and G0s2 genes expression in the inguinal WAT. The decrease in Lipe and the increase in Abhd5 and G0s2 genes expression was associated with lower rate of stimulated lipolysis. Administration of progesterone exerted no effect on Lipe, Abhd5 and G0s2 genes expression and stimulated lipolysis in the retroperitoneal WAT of females, as well as in the inguinal, epididymal and retroperitoneal WAT of males. In conclusion, our findings suggest that progesterone decreases the rate of lipolysis in the inguinal WAT of female rats, inhibiting the activity of both ATGL (by stimulating synthesis of G0S2 - specific inhibitor of the enzyme) and HSL (due to inhibition of Lipe gene expression).
Collapse
Affiliation(s)
- Ewa Stelmanska
- Department of Biochemistry, Medical University of Gdansk, Debinki 1, 80-211 Gdansk, Poland
| | - Sylwia Szrok
- Department of Biochemistry, Medical University of Gdansk, Debinki 1, 80-211 Gdansk, Poland
| | - Julian Swierczynski
- Department of Biochemistry, Medical University of Gdansk, Debinki 1, 80-211 Gdansk, Poland.
| |
Collapse
|
313
|
Guo D, Bell EH, Mischel P, Chakravarti A. Targeting SREBP-1-driven lipid metabolism to treat cancer. Curr Pharm Des 2015; 20:2619-26. [PMID: 23859617 DOI: 10.2174/13816128113199990486] [Citation(s) in RCA: 213] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 06/24/2013] [Indexed: 01/17/2023]
Abstract
Metabolic reprogramming is a hallmark of cancer. Oncogenic growth signaling regulates glucose, glutamine and lipid metabolism to meet the bioenergetics and biosynthetic demands of rapidly proliferating tumor cells. Emerging evidence indicates that sterol regulatory element-binding protein 1 (SREBP-1), a master transcription factor that controls lipid metabolism, is a critical link between oncogenic signaling and tumor metabolism. We recently demonstrated that SREBP-1 is required for the survival of mutant EGFR-containing glioblastoma, and that this pro-survival metabolic pathway is mediated, in part, by SREBP-1-dependent upregulation of the fatty acid synthesis and low density lipoprotein (LDL) receptor (LDLR). These results have identified EGFR/PI3K/Akt/SREBP-1 signaling pathway that promotes growth and survival in glioblastoma, and potentially other cancer types. Here, we summarize recent insights in the understanding of cancer lipid metabolism, and discuss the evidence linking SREBP-1 with PI3K/Akt signaling-controlled glycolysis and with Myc-regulated glutaminolysis to lipid metabolism. We also discuss the development of potential drugs targeting the SREBP-1- driven lipid metabolism as anti-cancer agents.
Collapse
Affiliation(s)
| | | | | | - Arnab Chakravarti
- Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center and Arthur G. James Cancer Hospital, Columbus, OH 43210, USA.
| |
Collapse
|
314
|
Kamoun J, Schué M, Messaoud W, Baignol J, Point V, Mateos-Diaz E, Mansuelle P, Gargouri Y, Parsiegla G, Cavalier JF, Carrière F, Aloulou A. Biochemical characterization of Yarrowia lipolytica LIP8, a secreted lipase with a cleavable C-terminal region. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:129-40. [DOI: 10.1016/j.bbalip.2014.10.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 10/23/2014] [Accepted: 10/27/2014] [Indexed: 10/24/2022]
|
315
|
Rengachari S, Aschauer P, Sturm C, Oberer M. Purification, crystallization and preliminary X-ray diffraction analysis of a soluble variant of the monoglyceride lipase Yju3p from the yeast Saccharomyces cerevisiae. Acta Crystallogr F Struct Biol Commun 2015; 71:243-6. [PMID: 25664804 PMCID: PMC4321484 DOI: 10.1107/s2053230x15001557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 01/23/2015] [Indexed: 11/10/2022] Open
Abstract
The protein Yju3p is the orthologue of monoglyceride lipases in the yeast Saccharomyces cerevisiae. A soluble variant of this lipase termed s-Yju3p (38.3 kDa) was generated and purified to homogeneity by affinity and size-exclusion chromatography. s-Yju3p was crystallized in a vapour-diffusion setup at 293 K and a complete data set was collected to 2.4 Å resolution. The crystal form was orthorhombic (space group P212121), with unit-cell parameters a = 77.2, b = 108.6, c = 167.7 Å. The asymmetric unit contained four molecules with a solvent content of 46.4%.
Collapse
Affiliation(s)
- Srinivasan Rengachari
- Institute of Molecular Biology, University of Graz, Humboldtstrasse 50/3, 8010 Graz, Austria
| | - Philipp Aschauer
- Institute of Molecular Biology, University of Graz, Humboldtstrasse 50/3, 8010 Graz, Austria
| | - Christian Sturm
- Institute of Molecular Biology, University of Graz, Humboldtstrasse 50/3, 8010 Graz, Austria
| | - Monika Oberer
- Institute of Molecular Biology, University of Graz, Humboldtstrasse 50/3, 8010 Graz, Austria
| |
Collapse
|
316
|
Heier C, Zimmermann R. The sparing use of fat: G0s2 controls lipolysis and fatty acid oxidation. Diabetologia 2015; 58:7-9. [PMID: 25351607 DOI: 10.1007/s00125-014-3430-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 10/06/2014] [Indexed: 10/24/2022]
Affiliation(s)
- Christoph Heier
- Institute of Molecular Biosciences, University of Graz, Heinrichstrasse 31A, 8010, Graz, Austria
| | | |
Collapse
|
317
|
Varma V, Boros LG, Nolen GT, Chang CW, Wabitsch M, Beger RD, Kaput J. Metabolic fate of fructose in human adipocytes: a targeted 13C tracer fate association study. Metabolomics 2015; 11:529-544. [PMID: 25972768 PMCID: PMC4419153 DOI: 10.1007/s11306-014-0716-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 07/18/2014] [Indexed: 11/12/2022]
Abstract
The development of obesity is becoming an international problem and the role of fructose is unclear. Studies using liver tissue and hepatocytes have contributed to the understanding of fructose metabolism. Excess fructose consumption also affects extra hepatic tissues including adipose tissue. The effects of fructose on human adipocytes are not yet fully characterized, although in vivo studies have noted increased adiposity and weight gain in response to fructose sweetened-beverages. In order to understand and predict the metabolic responses of adipocytes to fructose, this study examined differentiating and differentiated human adipocytes in culture, exposed to a range of fructose concentrations equivalent to that reported in blood after consuming fructose. A stable isotope based dynamic profiling method using [U-13C6]-d-fructose tracer was used to examine the metabolism and fate of fructose. A targeted stable isotope tracer fate association method was used to analyze metabolic fluxes and flux surrogates with exposure to escalating fructose concentration. This study demonstrated that fructose stimulates anabolic processes in adipocytes robustly, including glutamate and de novo fatty acid synthesis. Furthermore, fructose also augments the release of free palmitate from fully differentiated adipocytes. These results imply that in the presence of fructose, the metabolic response of adipocytes in culture is altered in a dose dependent manner, particularly favoring increased glutamate and fatty acid synthesis and release, warranting further in vivo studies.
Collapse
Affiliation(s)
- Vijayalakshmi Varma
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
| | - László G. Boros
- SiDMAP LLC, Los Angeles, CA 90064 USA
- Los Angeles Biomedical Research Institute (LABIOMED), Harbor-UCLA Medical Center, Torrance, CA 90502 USA
- Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502 USA
| | - Greg T. Nolen
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
| | - Ching-Wei Chang
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research, Jefferson, AR 72079 USA
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetology, University of Ulm, Ulm, Germany
| | - Richard D. Beger
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
| | - Jim Kaput
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
- Systems Nutrition and Health, Nestle Institute of Health Sciences, Lausanne, Switzerland
| |
Collapse
|
318
|
Chiang HC, Kuo YT, Shen CC, Lin YH, Wang SL, Tsou TC. Mono(2-ethylhexyl)phthalate accumulation disturbs energy metabolism of fat cells. Arch Toxicol 2014; 90:589-601. [PMID: 25543134 DOI: 10.1007/s00204-014-1446-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Accepted: 12/17/2014] [Indexed: 12/01/2022]
Abstract
Phthalates are lipophilic and tend to accumulate in adipose tissue, an important regulator of energy balance and glucose homeostasis. The study aimed to determine whether cellular phthalate accumulation influenced fat cell energy metabolism. Following a 3-day treatment with adipogenesis-inducing medium and a 2-day treatment with adipogenesis-maintaining medium, 3T3-L1 cells differentiated into adipocytes in the presence of a phthalate at a clinically relevant concentration (30-300 μM) for another 6 days. Two phthalates, di(2-ethylhexyl)phthalate and di-n-butylphthalate, and their metabolites, mono(2-ethylhexyl)phthalate (MEHP) and mono-n-butylphthalate, were used here. The phthalate treatments caused no marked effect on cytotoxicity and adipogenesis. Only the MEHP-treated adipocytes were found having smaller lipid droplets; MEHP accumulated in cells in a dose- and time-dependent manner. The MEHP-treated adipocytes exhibited significant increases in lipolysis and glucose uptake; quantitative real-time polymerase chain reaction (qPCR) analysis revealed correlated changes in expression of marker genes involved in adipogenesis, lipid metabolism, and glucose uptake. Analysis of oxygen consumption rate (a mitochondrial respiration indicator) and extracellular acidification rate (a glycolysis indicator) indicated a higher energy metabolism in the adipocytes. qPCR analysis of critical genes involved in mitochondrial biogenesis and/or energy metabolism showed that expression of peroxisome proliferator-activated receptor γ coactivator-1α, sirtuin 3, and protein kinase A were significantly enhanced in the MEHP-treated adipocytes. In vitro evidence of MEHP impacts on lipolysis, glucose uptake/glycolysis, and mitochondrial respiration/biogenesis demonstrates that MEHP accumulation disturbs energy metabolism of fat cells.
Collapse
Affiliation(s)
- Huai-chih Chiang
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 350, Taiwan
| | - Ya-Ting Kuo
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 350, Taiwan
| | - Chih-Che Shen
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 350, Taiwan
| | - Yi-Hua Lin
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 350, Taiwan
| | - Shu-Li Wang
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 350, Taiwan
| | - Tsui-Chun Tsou
- Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 350, Taiwan.
| |
Collapse
|
319
|
Ertunc ME, Sikkeland J, Fenaroli F, Griffiths G, Daniels MP, Cao H, Saatcioglu F, Hotamisligil GS. Secretion of fatty acid binding protein aP2 from adipocytes through a nonclassical pathway in response to adipocyte lipase activity. J Lipid Res 2014; 56:423-34. [PMID: 25535287 DOI: 10.1194/jlr.m055798] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Adipocyte fatty acid binding protein 4, aP2, contributes to the pathogenesis of several common diseases including type 2 diabetes, atherosclerosis, fatty liver disease, asthma, and cancer. Although the biological functions of aP2 have classically been attributed to its intracellular action, recent studies demonstrated that aP2 acts as an adipokine to regulate systemic metabolism. However, the mechanism and regulation of aP2 secretion remain unknown. Here, we demonstrate a specific role for lipase activity in aP2 secretion from adipocytes in vitro and ex vivo. Our results show that chemical inhibition of lipase activity, genetic deficiency of adipose triglyceride lipase and, to a lesser extent, hormone-sensitive lipase blocked aP2 secretion from adipocytes. Increased lipolysis and lipid availability also contributed to aP2 release as determined in perilipin1-deficient adipose tissue explants ex vivo and upon treatment with lipids in vivo and in vitro. In addition, we identify a nonclassical route for aP2 secretion in exosome-like vesicles and show that aP2 is recruited to this pathway upon stimulation of lipolysis. Given the effect of circulating aP2 on glucose metabolism, these data support that targeting aP2 or the lipolysis-dependent secretory pathway may present novel mechanistic and translational opportunities in metabolic disease.
Collapse
Affiliation(s)
- Meric Erikci Ertunc
- Department of Genetics and Complex Diseases Harvard School of Public Health, Boston, MA Sabri Ülker Center, Harvard School of Public Health, Boston, MA
| | - Jørgen Sikkeland
- Department of Biosciences, National Institutes of Health, Bethesda, MD
| | - Federico Fenaroli
- Department of Biosciences, National Institutes of Health, Bethesda, MD
| | - Gareth Griffiths
- Department of Biosciences, National Institutes of Health, Bethesda, MD
| | - Mathew P Daniels
- University of Oslo, Oslo, Norway; and National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Haiming Cao
- University of Oslo, Oslo, Norway; and National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Fahri Saatcioglu
- Department of Biosciences, National Institutes of Health, Bethesda, MD
| | - Gökhan S Hotamisligil
- Department of Genetics and Complex Diseases Harvard School of Public Health, Boston, MA Sabri Ülker Center, Harvard School of Public Health, Boston, MA
| |
Collapse
|
320
|
Vishnu Varthini L, Selvaraju K, Srinivasan M, Nachiappan V. ROG1 encodes a monoacylglycerol lipase in Saccharomyces cerevisiae. FEBS Lett 2014; 589:23-30. [PMID: 25433290 DOI: 10.1016/j.febslet.2014.11.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 11/13/2014] [Accepted: 11/14/2014] [Indexed: 11/30/2022]
Abstract
Lipid metabolism is extensively studied in Saccharomyces cerevisiae. Here, we report that revertant of glycogen synthase kinase mutation-1 (Rog1p) possesses monoacylglycerol (MAG) lipase activity in S. cerevisiae. The lipase activity of Rog1p was confirmed in two ways: through analysis of a strain with a double deletion of ROG1 and monoglyceride lipase YJU3 (yju3Δrog1Δ) and by site-directed mutagenesis of the ROG1 lipase motif (GXSXG). Rog1p is localized in both the cytosol and the nucleus. Overexpression of ROG1 in a ROG1-deficient strain resulted in an accumulation of reactive oxygen species. These results suggest that Rog1p is a MAG lipase that regulates lipid homeostasis.
Collapse
Affiliation(s)
| | - Kandasamy Selvaraju
- Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India
| | - Malathi Srinivasan
- CSIR-Central Food Technological Research Institute, Lipidomics Center, Allalasandra, GKVK Post, Bellary Road, Bangalore 560 065, Karnataka, India
| | - Vasanthi Nachiappan
- Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India.
| |
Collapse
|
321
|
Sahu-Osen A, Montero-Moran G, Schittmayer M, Fritz K, Dinh A, Chang YF, McMahon D, Boeszoermenyi A, Cornaciu I, Russell D, Oberer M, Carman GM, Birner-Gruenberger R, Brasaemle DL. CGI-58/ABHD5 is phosphorylated on Ser239 by protein kinase A: control of subcellular localization. J Lipid Res 2014; 56:109-21. [PMID: 25421061 PMCID: PMC4274058 DOI: 10.1194/jlr.m055004] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
CGI-58/ABHD5 coactivates adipose triglyceride lipase (ATGL). In adipocytes, CGI-58 binds to perilipin 1A on lipid droplets under basal conditions, preventing interaction with ATGL. Upon activation of protein kinase A (PKA), perilipin 1A is phosphorylated and CGI-58 rapidly disperses into the cytoplasm, enabling lipase coactivation. Because the amino acid sequence of murine CGI-58 has a predicted PKA consensus sequence of RKYS239S240, we hypothesized that phosphorylation of CGI-58 is involved in this process. We show that Ser239 of murine CGI-58 is a substrate for PKA using phosphoamino acid analysis, MS, and immunoblotting approaches to study phosphorylation of recombinant CGI-58 and endogenous CGI-58 of adipose tissue. Phosphorylation of CGI-58 neither increased nor impaired coactivation of ATGL in vitro. Moreover, Ser239 was not required for CGI-58 function to increase triacylglycerol turnover in human neutral lipid storage disorder fibroblasts that lack endogenous CGI-58. Both CGI-58 and S239A/S240A-mutated CGI-58 localized to perilipin 1A-coated lipid droplets in cells. When PKA was activated, WT CGI-58 dispersed into the cytoplasm, whereas substantial S239A/S240A-mutated CGI-58 remained on lipid droplets. Perilipin phosphorylation also contributed to CGI-58 dispersion. PKA-mediated phosphorylation of CGI-58 is required for dispersion of CGI-58 from perilipin 1A-coated lipid droplets, thereby increasing CGI-58 availability for ATGL coactivation.
Collapse
Affiliation(s)
- Anita Sahu-Osen
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria A-8036, and Omics Center Graz, BioTechMed-Graz, Graz, Austria A-8010
| | - Gabriela Montero-Moran
- Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 Departments of Nutritional Sciences Rutgers, The State University of New Jersey, New Brunswick, NJ 08901
| | - Matthias Schittmayer
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria A-8036, and Omics Center Graz, BioTechMed-Graz, Graz, Austria A-8010
| | - Katarina Fritz
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria A-8036, and Omics Center Graz, BioTechMed-Graz, Graz, Austria A-8010
| | - Anna Dinh
- Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 Departments of Nutritional Sciences Rutgers, The State University of New Jersey, New Brunswick, NJ 08901
| | - Yu-Fang Chang
- Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901
| | - Derek McMahon
- Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 Departments of Nutritional Sciences Rutgers, The State University of New Jersey, New Brunswick, NJ 08901
| | | | - Irina Cornaciu
- Institute of Molecular Biosciences, University of Graz, Graz, Austria A-8010
| | - Deanna Russell
- Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 Departments of Nutritional Sciences Rutgers, The State University of New Jersey, New Brunswick, NJ 08901
| | - Monika Oberer
- Institute of Molecular Biosciences, University of Graz, Graz, Austria A-8010
| | - George M Carman
- Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901
| | - Ruth Birner-Gruenberger
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria A-8036, and Omics Center Graz, BioTechMed-Graz, Graz, Austria A-8010
| | - Dawn L Brasaemle
- Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 Departments of Nutritional Sciences Rutgers, The State University of New Jersey, New Brunswick, NJ 08901
| |
Collapse
|
322
|
Crotonis Fructus and Its Constituent, Croton Oil, Stimulate Lipolysis in OP9 Adipocytes. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:780385. [PMID: 25435891 PMCID: PMC4244682 DOI: 10.1155/2014/780385] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 10/23/2014] [Indexed: 12/21/2022]
Abstract
Introduction. Crotonis fructus (CF) is the mature fruit of Croton tiglium L. and has been used for the treatment of gastrointestinal disturbance in Asia. It is well known that the main component of CF is croton oil (CO). The present study is to investigate the effects of CF extracts (CFE) and CO on lipolysis in OP9 adipocytes. Methods. Glycerol release to the culture supernatants was used as a marker of adipocyte lipolysis. Results. Treatment with various concentrations of CFE and CO stimulates glycerol release in a dose-dependent manner. The increase in glycerol release by CFE is more potent than isoproterenol, which is a β-adrenergic agonist as a positive control in our system. The increased lipolysis by CFE and CO was accompanied by an increase of phosphorylated hormone sensitive lipase (pHSL) but not nonphosphorylated HSL protein and mRNA. Pretreatment with H89, which is a protein kinase A inhibitor, significantly abolished the CFE- and CO-induced glycerol release in OP9 adipocytes. These results suggest that CFE and CO may be a candidate for the development of a lipolysis-stimulating agent in adipocytes.
Collapse
|
323
|
Camus G, Schweiger M, Herker E, Harris C, Kondratowicz AS, Tsou CL, Farese RV, Herath K, Previs SF, Roddy TP, Pinto S, Zechner R, Ott M. The hepatitis C virus core protein inhibits adipose triglyceride lipase (ATGL)-mediated lipid mobilization and enhances the ATGL interaction with comparative gene identification 58 (CGI-58) and lipid droplets. J Biol Chem 2014; 289:35770-80. [PMID: 25381252 DOI: 10.1074/jbc.m114.587816] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Liver steatosis is a common health problem associated with hepatitis C virus (HCV) and an important risk factor for the development of liver fibrosis and cancer. Steatosis is caused by triglycerides (TG) accumulating in lipid droplets (LDs), cellular organelles composed of neutral lipids surrounded by a monolayer of phospholipids. The HCV nucleocapsid core localizes to the surface of LDs and induces steatosis in cultured cells and mouse livers by decreasing intracellular TG degradation (lipolysis). Here we report that core at the surface of LDs interferes with the activity of adipose triglyceride lipase (ATGL), the key lipolytic enzyme in the first step of TG breakdown. Expressing core in livers or mouse embryonic fibroblasts of ATGL(-/-) mice no longer decreases TG degradation as observed in LDs from wild-type mice, supporting the model that core reduces lipolysis by engaging ATGL. Core must localize at LDs to inhibit lipolysis, as ex vivo TG hydrolysis is impaired in purified LDs coated with core but not when free core is added to LDs. Coimmunoprecipitation experiments revealed that core does not directly interact with the ATGL complex but, unexpectedly, increased the interaction between ATGL and its activator CGI-58 as well as the recruitment of both proteins to LDs. These data link the anti-lipolytic activity of the HCV core protein with altered ATGL binding to CGI-58 and the enhanced association of both proteins with LDs.
Collapse
Affiliation(s)
- Gregory Camus
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158
| | - Martina Schweiger
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158, Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Eva Herker
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158, UCSF Liver Center, University of California, San Francisco, California 94158, Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology, 20251 Hamburg, Germany
| | - Charles Harris
- UCSF Liver Center, University of California, San Francisco, California 94158, Gladstone Institute of Cardiovascular Disease, San Francisco, California 94158, Department of Medicine, University of California, San Francisco, California 94158, Division of Endocrinology Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Andrew S Kondratowicz
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158
| | - Chia-Lin Tsou
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158
| | - Robert V Farese
- UCSF Liver Center, University of California, San Francisco, California 94158, Gladstone Institute of Cardiovascular Disease, San Francisco, California 94158, Department of Medicine, University of California, San Francisco, California 94158, Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158, and
| | - Kithsiri Herath
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Stephen F Previs
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Thomas P Roddy
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Shirly Pinto
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Melanie Ott
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158, UCSF Liver Center, University of California, San Francisco, California 94158, Department of Medicine, University of California, San Francisco, California 94158,
| |
Collapse
|
324
|
Liu D, Yang A, Wu C, Guo P, Proksch P, Lin W. Lipid-lowering effects of farnesylquinone and related analogues from the marine-derived Streptomyces nitrosporeus. Bioorg Med Chem Lett 2014; 24:5288-93. [DOI: 10.1016/j.bmcl.2014.09.049] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 08/29/2014] [Accepted: 09/17/2014] [Indexed: 11/28/2022]
|
325
|
Joffin N, Jaubert AM, Durant S, Bastin J, De Bandt JP, Cynober L, Moinard C, Coumoul X, Forest C, Noirez P. Citrulline reduces glyceroneogenesis and induces fatty acid release in visceral adipose tissue from overweight rats. Mol Nutr Food Res 2014; 58:2320-30. [PMID: 25271764 DOI: 10.1002/mnfr.201400507] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/15/2014] [Accepted: 09/21/2014] [Indexed: 12/21/2022]
Abstract
SCOPE High-fat diet (HFD) increases visceral adipose tissue (AT). Our aim was to evaluate whether citrulline (CIT) affected nonesterified fatty acid (NEFA) metabolism in AT from HFD-fed rats. METHODS AND RESULTS Rats were fed for 8 weeks with either a control diet (CD) or HFD. Retroperitoneal AT explants were exposed to 2.5 mmol/L CIT for 24 h. We analyzed lipolysis, beta-oxidation, glyceroneogenesis, and the expression of the key associated enzymes. CIT doubled NEFA release selectively in HFD AT. Phosphorylation of hormone-sensitive lipase was upregulated 50 and 100% by CIT in CD and HFD AT, respectively. Under CIT, beta-oxidation increased similarly whatever the diet, whereas glyceroneogenesis, which permits NEFA re-esterification, was downregulated 50 and 80% in CD and HFD AT, respectively. In the latter, the important decrease in re-esterification probably explains the rise of NEFA release. A pretreatment with the nitric oxide synthase inhibitor N ω-nitro-l-arginine methyl ester abolished CIT effects. CONCLUSION These results demonstrate direct lipolytic and antiglyceroneogenic effects of CIT on CD and HFD AT. The selective CIT-mediated NEFA release from HFD AT was probably the consequence of the drastic decrease in glyceroneogenesis and nitric oxide was a mediator of CIT effects. These results provide evidence for a direct action of CIT on AT to reduce overweight.
Collapse
Affiliation(s)
- Nolwenn Joffin
- Université Paris Descartes, Sorbonne Paris Cité, France; Institut National de la Santé et de la Recherche Médicale UMR-S 1124, Faculté des Sciences Fondamentales et Biomédicales, Pharmacologie Toxicologie et Signalisation Cellulaire, Paris, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|
326
|
Ramos SV, MacPherson REK, Turnbull PC, Bott KN, LeBlanc P, Ward WE, Peters SJ. Higher PLIN5 but not PLIN3 content in isolated skeletal muscle mitochondria following acute in vivo contraction in rat hindlimb. Physiol Rep 2014; 2:2/10/e12154. [PMID: 25318747 PMCID: PMC4254090 DOI: 10.14814/phy2.12154] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Contraction-mediated lipolysis increases the association of lipid droplets and mitochondria, indicating an important role in the passage of fatty acids from lipid droplets to mitochondria in skeletal muscle. PLIN3 and PLIN5 are of particular interest to the lipid droplet-mitochondria interaction because PLIN3 is able to move about within cells and PLIN5 associates with skeletal muscle mitochondria. This study primarily investigated: 1) if PLIN3 is detected in skeletal muscle mitochondrial fraction; and 2) if mitochondrial protein content of PLIN3 and/or PLIN5 changes following stimulated contraction. A secondary aim was to determine if PLIN3 and PLIN5 associate and whether this changes following contraction. Male Long Evans rats (n = 21; age, 52 days; weight = 317 ± 6 g) underwent 30 min of hindlimb stimulation (10 msec impulses, 100 Hz/3 sec at 10-20 V; train duration 100 msec). Contraction induced a ~50% reduction in intramuscular lipid content measured by oil red-O staining of red gastrocnemius muscle. Mitochondria were isolated from red gastrocnemius muscle by differential centrifugation and proteins were detected by western blotting. Mitochondrial PLIN5 content was ~1.6-fold higher following 30 min of contraction and PLIN3 content was detected in the mitochondrial fraction, and unchanged following contraction. An association between PLIN3 and PLIN5 was observed and remained unaltered following contraction. PLIN5 may play a role in mitochondria during lipolysis, which is consistent with a role in facilitating/regulating mitochondrial fatty acid oxidation. PLIN3 and PLIN5 may be working together on the lipid droplet and mitochondria during contraction-induced lipolysis.
Collapse
Affiliation(s)
- Sofhia V Ramos
- Department of Kinesiology, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada Center for Bone and Muscle Health, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada
| | - Rebecca E K MacPherson
- Center for Bone and Muscle Health, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada
| | - Patrick C Turnbull
- Department of Kinesiology, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada Center for Bone and Muscle Health, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada
| | - Kirsten N Bott
- Department of Kinesiology, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada Center for Bone and Muscle Health, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada
| | - Paul LeBlanc
- Center for Bone and Muscle Health, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada Department of Health Science, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada
| | - Wendy E Ward
- Department of Kinesiology, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada Center for Bone and Muscle Health, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada Department of Health Science, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada
| | - Sandra J Peters
- Department of Kinesiology, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada Center for Bone and Muscle Health, Brock University, 500 Glenridge Ave, St Catharines, L2S 3A1, Ontario, Canada
| |
Collapse
|
327
|
Bae CR, Park YK, Cha YS. Quercetin-rich onion peel extract suppresses adipogenesis by down-regulating adipogenic transcription factors and gene expression in 3T3-L1 adipocytes. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2014; 94:2655-2660. [PMID: 24634340 DOI: 10.1002/jsfa.6604] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 02/02/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND Onion peel contains a high amount of quercetin, which has been reported to have anti-cholesterol, antithrombotic and insulin-sensitizing properties. This study aimed to elucidate the anti-adipogenic effects of quercetin-rich onion peel extract (OPE) and to compare it with commercially available quercetin using 3T3-L1 preadipocytes. RESULTS Without affecting cell viability, both OPE and quercetin averted adipogenesis, as characterized by dose-dependent decreases in intracellular triglyceride content and glycerol 3-phosphate dehydrogenase activity, but the effect was more pronounced with OPE than with quercetin. The mRNA expression levels of key adipogenic genes such as PPARγ, C/EBPα, FABP4, aP2 and LPL were decreased in a dose-dependent manner by both OPE and quercetin. CONCLUSION The results indicate that OPE treatment significantly prevents intracellular lipid accumulation via hyperactivation of genes regulating lipolysis as compared with quercetin alone.
Collapse
Affiliation(s)
- Cho-Rong Bae
- Department of Food Science and Human Nutrition, and Research Institute of Humans Ecology, Chonbuk National University, 567 Baekje-daero, deokjin-gu, Jeonju-si, Jeollabuk-do, 561-756, Republic of Korea
| | | | | |
Collapse
|
328
|
Liu P, Li C, Huang J, Ji H. Regulation of adipocytes lipolysis by n-3 HUFA in grass carp (Ctenopharyngodon idellus) in vitro and in vivo. FISH PHYSIOLOGY AND BIOCHEMISTRY 2014; 40:1447-1460. [PMID: 24737494 DOI: 10.1007/s10695-014-9939-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 04/07/2014] [Indexed: 06/03/2023]
Abstract
N-3 highly unsaturated fatty acids (n-3 HUFA) have been shown to inhibit body fat accumulation in animals. To clarify the mechanism of this fat-lowering effect of n-3 HUFA in grass carp (Ctenopharyngodon idellus), two experiments were conducted. In experiment 1, isolated grass carp mature adipocytes were incubated with docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) at different concentrations for 6 h. The release of glycerol to the medium was detected, and the expression of the lipolysis-related genes was analyzed. In experiment 2, a 95-day feeding trial was conducted with two diets formulated with either lard oil (as control) or fish oil (supplying n-3 HUFA as treatment) as the main lipid source. The glycerol and free fatty acid (FFA) released from the isolated adipocytes of both groups were detected after the feeding period. The expression of select lipolysis-related genes in adipose tissue was also analyzed. The results from experiment 1 showed that the release of glycerol was significantly increased by DHA and EPA (P < 0.05). Moreover, the expression of lipolysis-related genes, such as adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), tumor necrosis factor α (TNFα) and leptin, was also significantly elevated in the treatment group (P < 0.05). Experiment 2 demonstrated that glycerol and FFA release from the isolated adipocytes were significantly higher in the treatment group compared to the control group (P < 0.05). The expression level of ATGL, HSL, TNFα and leptin in the treatment group was significantly higher than in the control group (P < 0.05). The present results provide novel evidence that n-3 HUFAs could regulate grass carp adipocyte lipolysis in vitro or in vivo, and the effect might be in part associated with their influence on the expression of lipolysis-related genes and lipolysis-related adipokines genes.
Collapse
Affiliation(s)
- Pin Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, China
| | | | | | | |
Collapse
|
329
|
Cerk IK, Salzburger B, Boeszoermenyi A, Heier C, Pillip C, Romauch M, Schweiger M, Cornaciu I, Lass A, Zimmermann R, Zechner R, Oberer M. A peptide derived from G0/G1 switch gene 2 acts as noncompetitive inhibitor of adipose triglyceride lipase. J Biol Chem 2014; 289:32559-70. [PMID: 25258314 PMCID: PMC4239610 DOI: 10.1074/jbc.m114.602599] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The protein G0/G1 switch gene 2 (G0S2) is a small basic protein that functions as an endogenous inhibitor of adipose triglyceride lipase (ATGL), a key enzyme in intracellular lipolysis. In this study, we identified a short sequence covering residues Lys-20 to Ala-52 in G0S2 that is still fully capable of inhibiting mouse and human ATGL. We found that a synthetic peptide corresponding to this region inhibits ATGL in a noncompetitive manner in the nanomolar range. This peptide is highly selective for ATGL and does not inhibit other lipases, including hormone-sensitive lipase, monoacylglycerol lipase, lipoprotein lipase, and patatin domain-containing phospholipases 6 and 7. Because increased lipolysis is linked to the development of metabolic disorders, the inhibition of ATGL by G0S2-derived peptides may represent a novel therapeutic tool to modulate lipolysis.
Collapse
Affiliation(s)
- Ines K Cerk
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Barbara Salzburger
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Andras Boeszoermenyi
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Christoph Heier
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Christoph Pillip
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Matthias Romauch
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Martina Schweiger
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Irina Cornaciu
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Achim Lass
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Robert Zimmermann
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Rudolf Zechner
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Monika Oberer
- From the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| |
Collapse
|
330
|
Chen QL, Luo Z, Song YF, Wu K, Huang C, Pan YX, Zhu QL. Hormone-sensitive lipase in yellow catfish Pelteobagrus fulvidraco: molecular characterization, mRNA tissue expression and transcriptional regulation by leptin in vivo and in vitro. Gen Comp Endocrinol 2014; 206:130-8. [PMID: 25016050 DOI: 10.1016/j.ygcen.2014.06.031] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 06/18/2014] [Accepted: 06/19/2014] [Indexed: 11/18/2022]
Abstract
Hormone-sensitive lipase (hsl) plays a pivotal role in regulation of lipolysis in mammals, but information is very scarce about its gene structure and function in fish. In this study, two distinct hsl cDNAs, designated hsl1 and hsl2, were firstly isolated and characterized from yellow catfish Pelteobagrus fulvidraco. The validated cDNAs encoding for hsl1 and hsl2 were 2739 and 2629bp in length, encoding peptides of 679 and 813 amino acid residues, respectively, and shared 57.7% amino acid identity. The phylogenetic analysis revealed that hsl1 and hsl2 derived from paralogous genes that might have arisen during a teleost-specific genome duplication event. Both hsl mRNAs were expressed in a wide range of tissues, but the abundance of each hsl mRNA showed the tissue- and developmental stage-dependent expression patterns. Intraperitoneal injection in vivo and incubation in vitro of recombinant human leptin (rb-hLEP) stimulated the mRNA expression of hsl2, but not hsl1, in the liver and hepatocytes of P. fulvidraco, respectively, suggesting that two hsl isoforms might serve different roles in lipid metabolism. To our knowledge, for the first time, the present study provides evidence that two hsl mRNAs are differentially expressed with and among tissues during different developmental stages and also differentially regulated by leptin both in vivo and in vitro, which serves to increase our understanding on hsl physiological function in fish.
Collapse
Affiliation(s)
- Qi-Liang Chen
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China
| | - Zhi Luo
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China.
| | - Yu-Feng Song
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China
| | - Kun Wu
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China
| | - Chao Huang
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China
| | - Ya-Xiong Pan
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China
| | - Qing-Ling Zhu
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China
| |
Collapse
|
331
|
Placental lipases in pregnancies complicated by gestational diabetes mellitus (GDM). PLoS One 2014; 9:e104826. [PMID: 25118138 PMCID: PMC4130608 DOI: 10.1371/journal.pone.0104826] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Accepted: 07/14/2014] [Indexed: 12/29/2022] Open
Abstract
Infants of women with gestational diabetes mellitus (GDM) are more likely to be born large for gestational age with a higher percentage body fat. Elevated maternal lipids may contribute to this. Placental lipases such as lipoprotein lipase (LPL), endothelial lipase (EL) and hormone sensitive lipase (HSL) are involved in transferring lipids from mother to fetus. Previous studies of expression of these lipases in placentae in women with diabetes in pregnancy have reported divergent results. Intracellular lipases such as adipose triglyceride lipase (ATGL), and HSL are central to lipid droplet metabolism. The activities of these lipases are both influenced by Perilipin 1, and ATGL is also activated by a co-factor comparative gene identification-58 (CGI-58) and inhibited by G0/G1 switch gene 2 (GS02). None of these modifying factors or ATGL have been examined previously in placenta. The purpose of this study was therefore to examine the expression of ATGL, HSL, LPL, EL, as well as Perilipin 1, GS02 and CGI-58 in term pregnancies complicated by GDM. mRNA and protein expression of the lipases were measured in placentae from 17 women with GDM and 17 normoglycaemic pregnancies, matched for maternal BMI and gestational age of delivery. ATGL mRNA expression was increased and HSL mRNA expression reduced in placentae from GDM although there was no differences in protein expression of any of the lipases. All lipases were localised to trophoblasts and endothelial cells. The expression of Perilipin 1 and CGI-58 mRNA was increased and GS02 not altered in GDM. These results suggest that there is no difference in expression in these four lipases between GDM and normoglycaemic placentae, and therefore altered lipid transfer via these lipases does not contribute to large for gestational age in infants of women with GDM.
Collapse
|
332
|
Dichlberger A, Schlager S, Maaninka K, Schneider WJ, Kovanen PT. Adipose triglyceride lipase regulates eicosanoid production in activated human mast cells. J Lipid Res 2014; 55:2471-8. [PMID: 25114172 DOI: 10.1194/jlr.m048553] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human mast cells (MCs) contain TG-rich cytoplasmic lipid droplets (LDs) with high arachidonic acid (AA) content. Here, we investigated the functional role of adipose TG lipase (ATGL) in TG hydrolysis and the ensuing release of AA as substrate for eicosanoid generation by activated human primary MCs in culture. Silencing of ATGL in MCs by siRNAs induced the accumulation of neutral lipids in LDs. IgE-dependent activation of MCs triggered the secretion of the two major eicosanoids, prostaglandin D2 (PGD2) and leukotriene C4 (LTC4). The immediate release of PGD2 from the activated MCs was solely dependent on cyclooxygenase (COX) 1, while during the delayed phase of lipid mediator production, the inducible COX-2 also contributed to its release. Importantly, when ATGL-silenced MCs were activated, the secretion of both PGD2 and LTC4 was significantly reduced. Interestingly, the inhibitory effect on the release of LTC4 was even more pronounced in ATGL-silenced MCs than in cytosolic phospholipase A2-silenced MCs. These data show that ATGL hydrolyzes AA-containing TGs present in human MC LDs and define ATGL as a novel regulator of the substrate availability of AA for eicosanoid generation upon MC activation.
Collapse
Affiliation(s)
| | | | | | - Wolfgang J Schneider
- Department of Medical Biochemistry, Medical University Vienna, Max F. Perutz Laboratories, 1030 Vienna, Austria
| | | |
Collapse
|
333
|
Benedito-Palos L, Ballester-Lozano G, Pérez-Sánchez J. Wide-gene expression analysis of lipid-relevant genes in nutritionally challenged gilthead sea bream (Sparus aurata). Gene 2014; 547:34-42. [DOI: 10.1016/j.gene.2014.05.073] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/26/2014] [Accepted: 05/31/2014] [Indexed: 12/22/2022]
|
334
|
Aon MA, Bhatt N, Cortassa SC. Mitochondrial and cellular mechanisms for managing lipid excess. Front Physiol 2014; 5:282. [PMID: 25132820 PMCID: PMC4116787 DOI: 10.3389/fphys.2014.00282] [Citation(s) in RCA: 164] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 07/10/2014] [Indexed: 12/16/2022] Open
Abstract
Current scientific debates center on the impact of lipids and mitochondrial function on diverse aspects of human health, nutrition and disease, among them the association of lipotoxicity with the onset of insulin resistance in skeletal muscle, and with heart dysfunction in obesity and diabetes. Mitochondria play a fundamental role in aging and in prevalent acute or chronic diseases. Lipids are main mitochondrial fuels however these molecules can also behave as uncouplers and inhibitors of oxidative phosphorylation. Knowledge about the functional composition of these contradictory effects and their impact on mitochondrial-cellular energetics/redox status is incomplete. Cells store fatty acids (FAs) as triacylglycerol and package them into cytoplasmic lipid droplets (LDs). New emerging data shows the LD as a highly dynamic storage pool of FAs that can be used for energy reserve. Lipid excess packaging into LDs can be seen as an adaptive response to fulfilling energy supply without hindering mitochondrial or cellular redox status and keeping low concentration of lipotoxic intermediates. Herein we review the mechanisms of action and utilization of lipids by mitochondria reported in liver, heart and skeletal muscle under relevant physiological situations, e.g., exercise. We report on perilipins, a family of proteins that associate with LDs in response to loading of cells with lipids. Evidence showing that in addition to physical contact, mitochondria and LDs exhibit metabolic interactions is presented and discussed. A hypothetical model of channeled lipid utilization by mitochondria is proposed. Direct delivery and channeled processing of lipids in mitochondria could represent a reliable and efficient way to maintain reactive oxygen species (ROS) within levels compatible with signaling while ensuring robust and reliable energy supply.
Collapse
Affiliation(s)
- Miguel A Aon
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Niraj Bhatt
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Sonia C Cortassa
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine Baltimore, MD, USA
| |
Collapse
|
335
|
O'Sullivan D, van der Windt GJW, Huang SCC, Curtis JD, Chang CH, Buck MD, Qiu J, Smith AM, Lam WY, DiPlato LM, Hsu FF, Birnbaum MJ, Pearce EJ, Pearce EL. Memory CD8(+) T cells use cell-intrinsic lipolysis to support the metabolic programming necessary for development. Immunity 2014; 41:75-88. [PMID: 25001241 DOI: 10.1016/j.immuni.2014.06.005] [Citation(s) in RCA: 571] [Impact Index Per Article: 57.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Accepted: 06/18/2014] [Indexed: 12/11/2022]
Abstract
Generation of CD8(+) memory T cells requires metabolic reprogramming that is characterized by enhanced mitochondrial fatty-acid oxidation (FAO). However, where the fatty acids (FA) that fuel this process come from remains unclear. While CD8(+) memory T cells engage FAO to a greater extent, we found that they acquired substantially fewer long-chain FA from their external environment than CD8(+) effector T (Teff) cells. Rather than using extracellular FA directly, memory T cells used extracellular glucose to support FAO and oxidative phosphorylation (OXPHOS), suggesting that lipids must be synthesized to generate the substrates needed for FAO. We have demonstrated that memory T cells rely on cell intrinsic expression of the lysosomal hydrolase LAL (lysosomal acid lipase) to mobilize FA for FAO and memory T cell development. Our observations link LAL to metabolic reprogramming in lymphocytes and show that cell intrinsic lipolysis is deterministic for memory T cell fate.
Collapse
Affiliation(s)
- David O'Sullivan
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Gerritje J W van der Windt
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Stanley Ching-Cheng Huang
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jonathan D Curtis
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Chih-Hao Chang
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Michael D Buck
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jing Qiu
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Amber M Smith
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Wing Y Lam
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Lisa M DiPlato
- The Institute for Diabetes, Obesity, and Metabolism, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Fong-Fu Hsu
- Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Morris J Birnbaum
- The Institute for Diabetes, Obesity, and Metabolism, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Edward J Pearce
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Erika L Pearce
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| |
Collapse
|
336
|
Mc Auley MT, Mooney KM. Lipid metabolism and hormonal interactions: impact on cardiovascular disease and healthy aging. Expert Rev Endocrinol Metab 2014; 9:357-367. [PMID: 30763995 DOI: 10.1586/17446651.2014.921569] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Populations in developed nations are aging gradually; it is predicted that by 2050 almost a quarter of the world's population will be over 60 years old, more than twice the figure at the turn of the 20th century. Although we are living longer, this does not mean the extra years will be spent in good health. Cardiovascular diseases are the primary cause of ill health and their prevalence increases with age. Traditionally, lipid biomarkers have been utilized to stratify disease risk and predict the onset of cardiovascular events. However, recent evidence suggests that hormonal interplay with lipid metabolism could have a significant role to play in modulating cardiovascular disease risk. This review will explore recent findings which have investigated the role hormones have on the dynamics of lipid metabolism. The aim is to offer an insight into potential avenues for therapeutic intervention.
Collapse
Affiliation(s)
- Mark T Mc Auley
- a School of Health Sciences, Liverpool Hope University, Taggart Avenue, Liverpool, L16 1JD, UK
| | - Kathleen M Mooney
- b Faculty of Health and Social Care, Edge Hill University, St Helens Road, Ormskirk, Lancashire, L39 4QP, UK
| |
Collapse
|
337
|
Friedrichs P, Saremi B, Winand S, Rehage J, Dänicke S, Sauerwein H, Mielenz M. Energy and metabolic sensing G protein-coupled receptors during lactation-induced changes in energy balance. Domest Anim Endocrinol 2014; 48:33-41. [PMID: 24906926 DOI: 10.1016/j.domaniend.2014.01.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 01/11/2014] [Accepted: 01/29/2014] [Indexed: 11/23/2022]
Abstract
The free fatty acid receptor FFA1, FFA2, and FFA3 and hydroxy-carboxylic acid receptor (HCA2) are G protein-coupled receptors, acting as energy and metabolic sensors. Herein, we characterized the tissue-specific mRNA abundance of genes encoding for these receptors at different stages of lactation. In addition, potential effects of supplementation with or without conjugated linoleic acids (CLA) were tested. Tissues from pluriparous cows (subcutaneous adipose tissue [SAT] and liver) and from primiparous cows (3 SAT locations, 3 visceral adipose tissues, liver, mammary gland, and skeletal muscle) were used from 2 separate trials. In primiparous cows, the mRNA abundance of all receptors (FFA3 was not detectable by the applied protocol in muscle and udder) was lowest in muscle (P < 0.05). With the exception of FFA1, gene expression of the investigated receptors was higher in adipose tissue than in the non-adipose tissue. Expression of FFA1 in liver (P < 0.03), FFAR2 in SAT (P < 0.01), and HCA2 in SAT (P < 0.01) from pluriparous cows changed during the observation period (days 21 to 252 relative to parturition). The correlation between mRNA abundance of HCA2 and peroxisome proliferator-activated receptor gamma (PPARG) and likewise PPARG2 (P < 0.01) in SAT indicates a link between HCA2 and PPARG. Differences in receptor mRNA abundance between the CLA-fed and the control animals were scarce and limited to HCA2 and FFA1 in 1 and 2 time points, respectively (less hepatic HCA2mRNA in CLA-fed pluriparous cows and greater FFA1 mRNA abundance in 2 visceral adipose tissue depots in CLA-treated primiparous cows). In view of the metabolic changes occurring during the different phases of lactation, in particular, the altered concentrations of non-esterified fatty acids and β-hydroxybutyrate acting as receptor ligands, the longitudinal tissue-specific characterization provided herein allows for a first insight into the regulation of these receptors at the gene expression level.
Collapse
Affiliation(s)
- P Friedrichs
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - B Saremi
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - S Winand
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - J Rehage
- Clinic for Cattle, School of Veterinary Medicine Hannover, 30173 Hannover, Germany
| | - S Dänicke
- Institute of Animal Nutrition, Friedrich-Loeffler-Institute (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany
| | - H Sauerwein
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany
| | - M Mielenz
- Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, Katzenburgweg 7 - 9, 53115 Bonn, Germany.
| |
Collapse
|
338
|
Lu M, Kho T, Munford RS. Prolonged triglyceride storage in macrophages: pHo trumps pO2 and TLR4. THE JOURNAL OF IMMUNOLOGY 2014; 193:1392-7. [PMID: 24973452 DOI: 10.4049/jimmunol.1400886] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Lipid-laden macrophages contribute to pathologies as diverse as atherosclerosis and tuberculosis. Three common stimuli are known to promote macrophage lipid storage: low tissue oxygen tension (pO2), low extracellular pH (pHo), and exposure to agonists such as bacterial LPS. Noting that cells responding to low pO2 or agonistic bacterial molecules often decrease pHo by secreting lactic and other carboxylic acids, we studied how pHo influences the stimulation of triacylglycerol (TAG) storage by low pO2 and LPS. We found that TAG retention after incubation for 48-72 h was inversely related to pHo when primary macrophages were cultured in 21% oxygen, 4% oxygen, or with LPS at either oxygen concentration. Maintaining pHo at ~7.4 was sufficient to prevent the increase in prolonged TAG storage induced by either low pO2 or LPS. The strong influence of pHo on TAG retention may explain why lipid-laden macrophages are found in some tissue environments and not in others. It is also possible that other long-term cellular changes currently attributed to low pO2 or bacterial agonists may be promoted, at least in part, by the decrease in pHo that these stimuli induce.
Collapse
Affiliation(s)
- Mingfang Lu
- Antibacterial Host Defense Unit, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Terry Kho
- Antibacterial Host Defense Unit, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Robert S Munford
- Antibacterial Host Defense Unit, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| |
Collapse
|
339
|
Cardamone MD, Tanasa B, Chan M, Cederquist CT, Andricovich J, Rosenfeld MG, Perissi V. GPS2/KDM4A pioneering activity regulates promoter-specific recruitment of PPARγ. Cell Rep 2014; 8:163-76. [PMID: 24953653 DOI: 10.1016/j.celrep.2014.05.041] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 04/18/2014] [Accepted: 05/19/2014] [Indexed: 01/09/2023] Open
Abstract
Timely and selective recruitment of transcription factors to their appropriate DNA-binding sites represents a critical step in regulating gene activation; however, the regulatory strategies underlying each factor's effective recruitment to specific promoter and/or enhancer regions are not fully understood. Here, we identify an unexpected regulatory mechanism by which promoter-specific binding, and therefore function, of peroxisome proliferator-activator receptor γ (PPARγ) in adipocytes requires G protein suppressor 2 (GPS2) to prime the local chromatin environment via inhibition of the ubiquitin ligase RNF8 and stabilization of the H3K9 histone demethylase KDM4A/JMJD2. Integration of genome-wide profiling data indicates that the pioneering activity of GPS2/KDM4A is required for PPARγ-mediated regulation of a specific transcriptional program, including the lipolytic enzymes adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL). Hence, our findings reveal that GPS2 exerts a biologically important function in adipose tissue lipid mobilization by directly regulating ubiquitin signaling and indirectly modulating chromatin remodeling to prime selected genes for activation.
Collapse
Affiliation(s)
- M Dafne Cardamone
- Biochemistry Department, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA
| | - Bogdan Tanasa
- Department of Medicine, University of California, San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Michelle Chan
- Biochemistry Department, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA
| | - Carly T Cederquist
- Biochemistry Department, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA
| | - Jaclyn Andricovich
- Biochemistry Department, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA
| | - Michael G Rosenfeld
- Department of Medicine, University of California, San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA; Howard Hughes Medical Institute, University of California, San Diego, School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Valentina Perissi
- Biochemistry Department, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA.
| |
Collapse
|
340
|
Xie X, Langlais P, Zhang X, Heckmann BL, Saarinen AM, Mandarino LJ, Liu J. Identification of a novel phosphorylation site in adipose triglyceride lipase as a regulator of lipid droplet localization. Am J Physiol Endocrinol Metab 2014; 306:E1449-59. [PMID: 24801391 PMCID: PMC4059987 DOI: 10.1152/ajpendo.00663.2013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adipose triglyceride lipase (ATGL), the rate-limiting enzyme for triacylglycerol (TG) hydrolysis, has long been known to be a phosphoprotein. However, the potential phosphorylation events that are involved in the regulation of ATGL function remain incompletely defined. Here, using a combinatorial proteomics approach, we obtained evidence that at least eight different sites of ATGL can be phosphorylated in adipocytes. Among them, Thr³⁷² resides within the hydrophobic region known to mediate lipid droplet (LD) targeting. Although it had no impact on the TG hydrolase activity, substitution of phosphorylation-mimic Asp for Thr³⁷² eliminated LD localization and LD-degrading capacity of ATGL expressed in HeLa cells. In contrast, mutation of Thr³⁷² to Ala gave a protein that bound LDs and functioned the same as the wild-type protein. In nonstimulated adipocytes, the Asp mutation led to decreased LD association and basal lipolytic activity of ATGL, whereas the Ala mutation produced opposite effects. Moreover, the LD translocation of ATGL upon β-adrenergic stimulation was also compromised by the Asp mutation. In accord with these findings, the Ala mutation promoted and the Asp mutation attenuated the capacity of ATGL to mediate lipolysis in adipocytes under both basal and stimulated conditions. Collectively, these studies identified Thr³⁷² as a novel phosphorylation site that may play a critical role in determining subcellular distribution as well as lipolytic action of ATGL.
Collapse
Affiliation(s)
- Xitao Xie
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona; HEALth Program, Mayo Clinic, Scottsdale, Arizona
| | | | - Xiaodong Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona; HEALth Program, Mayo Clinic, Scottsdale, Arizona
| | - Bradlee L Heckmann
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona; HEALth Program, Mayo Clinic, Scottsdale, Arizona; Mayo Graduate School, Rochester, Minnesota; and
| | - Alicia M Saarinen
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona; HEALth Program, Mayo Clinic, Scottsdale, Arizona
| | - Lawrence J Mandarino
- HEALth Program, Mayo Clinic, Scottsdale, Arizona; Division of Endocrinology, Mayo Clinic, Scottsdale, Arizona; Center for Metabolic and Vascular Biology, Arizona State University, Tempe, Arizona
| | - Jun Liu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona; HEALth Program, Mayo Clinic, Scottsdale, Arizona; Division of Endocrinology, Mayo Clinic, Scottsdale, Arizona;
| |
Collapse
|
341
|
Benn T, Kim B, Park YK, Wegner CJ, Harness E, Nam TG, Kim DO, Lee JS, Lee JY. Polyphenol-rich blackcurrant extract prevents inflammation in diet-induced obese mice. J Nutr Biochem 2014; 25:1019-25. [PMID: 25034502 DOI: 10.1016/j.jnutbio.2014.05.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/05/2014] [Accepted: 05/07/2014] [Indexed: 01/01/2023]
Abstract
Obesity is closely associated with chronic, low-grade inflammation. We investigated if polyphenol-rich blackcurrant extract (BCE) can prevent inflammation in vivo. Male C57BL/6J mice were fed a modified AIN-93M control diet containing high fat/high cholesterol (16% fat, 0.25% cholesterol by weight) or the control diet supplemented with 0.1% BCE (wt/wt) for 12 weeks. In BCE-fed mice, the percentage of body weight and adipocyte size of the epididymal fat were significantly lower than those of control mice. There were fewer crown-like structures (CLS) with concomitant decreases in F4/80, cluster of differentiation 68 and inhibitor of nuclear factor κB kinase ε (IKKε) mRNA in the epididymal adipose of BCE-fed mice. F4/80 and IKKε mRNA levels were positively correlated with CLS number. In the skeletal muscle of mice fed with BCE, mRNA expression of genes involved in energy expenditure and mitochondrial biogenesis, including PPARα, PPARδ, UCP-2, UCP-3 and mitochondrial transcription factor A, were significantly increased. When splenocytes from BCE-fed mice were stimulated by lipopolysaccharides, tumor necrosis factor α and interleukin-1β mRNA were significantly lower than control splenocytes. Together, the results suggest that BCE supplementation decreases obesity-induced inflammation in adipose tissue and splenocytes, at least in part, by modulating energy metabolism in skeletal muscle.
Collapse
Affiliation(s)
- Tyler Benn
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Bohkyung Kim
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Young-Ki Park
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Casey J Wegner
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Ellen Harness
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Tae-Gyu Nam
- Department of Food Science and Biotechnology, Kyung Hee University, Yongin, Gyeonggi-do 446-701, South Korea
| | - Dae-Ok Kim
- Department of Food Science and Biotechnology, Kyung Hee University, Yongin, Gyeonggi-do 446-701, South Korea
| | - Jong Suk Lee
- Gyeonggi Biocenter, Gyeonggi Institute of Science and Technology Promotion, Suwon, Gyeonggi-do 443-270, South Korea
| | - Ji-Young Lee
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA.
| |
Collapse
|
342
|
Joffin N, Jaubert AM, Durant S, Bastin J, De Bandt JP, Cynober L, Moinard C, Forest C, Noirez P. Citrulline induces fatty acid release selectively in visceral adipose tissue from old rats. Mol Nutr Food Res 2014; 58:1765-75. [DOI: 10.1002/mnfr.201400053] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/11/2014] [Accepted: 04/14/2014] [Indexed: 12/17/2022]
Affiliation(s)
- Nolwenn Joffin
- Université Paris Descartes; Sorbonne Paris Cité France
- Institut National de la Santé et de la Recherche Médicale UMR-S 1124; Faculté des Sciences Fondamentales et Biomédicales; Pharmacologie Toxicologie et Signalisation Cellulaire; Paris France
| | - Anne-Marie Jaubert
- Institut National de la Santé et de la Recherche Médicale UMR-S 1124; Faculté des Sciences Fondamentales et Biomédicales; Pharmacologie Toxicologie et Signalisation Cellulaire; Paris France
- Département de Biochimie et de Biologie Moléculaire; Faculté de Médecine Paris-Ile de France-Ouest; Université de Versailles Saint-Quentin en Yvelines; Versailles France
| | - Sylvie Durant
- Université Paris Descartes; Sorbonne Paris Cité France
- Institut National de la Santé et de la Recherche Médicale UMR-S 1124; Faculté des Sciences Fondamentales et Biomédicales; Pharmacologie Toxicologie et Signalisation Cellulaire; Paris France
| | - Jean Bastin
- Université Paris Descartes; Sorbonne Paris Cité France
- Institut National de la Santé et de la Recherche Médicale UMR-S 1124; Faculté des Sciences Fondamentales et Biomédicales; Pharmacologie Toxicologie et Signalisation Cellulaire; Paris France
| | - Jean-Pascal De Bandt
- Université Paris Descartes; Sorbonne Paris Cité France
- Laboratoire de Biologie de la Nutrition; Faculté des Sciences Pharmaceutiques et Biologiques; Paris France
- Service de Biochimie, Hôpital Cochin; Assistance Publique Hôpitaux de Paris; Paris France
| | - Luc Cynober
- Université Paris Descartes; Sorbonne Paris Cité France
- Laboratoire de Biologie de la Nutrition; Faculté des Sciences Pharmaceutiques et Biologiques; Paris France
- Service de Biochimie, Hôpital Cochin; Assistance Publique Hôpitaux de Paris; Paris France
| | - Christophe Moinard
- Université Paris Descartes; Sorbonne Paris Cité France
- Laboratoire de Biologie de la Nutrition; Faculté des Sciences Pharmaceutiques et Biologiques; Paris France
| | - Claude Forest
- Université Paris Descartes; Sorbonne Paris Cité France
- Institut National de la Santé et de la Recherche Médicale UMR-S 1124; Faculté des Sciences Fondamentales et Biomédicales; Pharmacologie Toxicologie et Signalisation Cellulaire; Paris France
| | - Philippe Noirez
- Université Paris Descartes; Sorbonne Paris Cité France
- Institut de Recherche Biomédicale et d’Epidémiologie du Sport; Paris France
- UFR des Sciences et Techniques des Activités Physiques et Sportives; Paris France
| |
Collapse
|
343
|
α/β-Hydrolase domain-6-accessible monoacylglycerol controls glucose-stimulated insulin secretion. Cell Metab 2014; 19:993-1007. [PMID: 24814481 DOI: 10.1016/j.cmet.2014.04.003] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 01/24/2014] [Accepted: 03/26/2014] [Indexed: 02/07/2023]
Abstract
Glucose metabolism in pancreatic β cells stimulates insulin granule exocytosis, and this process requires generation of a lipid signal. However, the signals involved in lipid amplification of glucose-stimulated insulin secretion (GSIS) are unknown. Here we show that in β cells, glucose stimulates production of lipolysis-derived long-chain saturated monoacylglycerols, which further increase upon inhibition of the membrane-bound monoacylglycerol lipase α/β-Hydrolase Domain-6 (ABHD6). ABHD6 expression in β cells is inversely proportional to GSIS. Exogenous monoacylglycerols stimulate β cell insulin secretion and restore GSIS suppressed by the pan-lipase inhibitor orlistat. Whole-body and β-cell-specific ABHD6-KO mice exhibit enhanced GSIS, and their islets show elevated monoacylglycerol production and insulin secretion in response to glucose. Inhibition of ABHD6 in diabetic mice restores GSIS and improves glucose tolerance. Monoacylglycerol binds and activates the vesicle priming protein Munc13-1, thereby inducing insulin exocytosis. We propose saturated monoacylglycerol as a signal for GSIS and ABHD6 as a negative modulator of insulin secretion.
Collapse
|
344
|
Abstract
In adipocytes the hydrolysis of TAG to produce fatty acids and glycerol under fasting conditions or times of elevated energy demands is tightly regulated by neuroendocrine signals, resulting in the activation of lipolytic enzymes. Among the classic regulators of lipolysis, adrenergic stimulation and the insulin-mediated control of lipid mobilisation are the best known. Initially, hormone-sensitive lipase (HSL) was thought to be the rate-limiting enzyme of the first lipolytic step, while we now know that adipocyte TAG lipase is the key enzyme for lipolysis initiation. Pivotal, previously unsuspected components have also been identified at the protective interface of the lipid droplet surface and in the signalling pathways that control lipolysis. Perilipin, comparative gene identification-58 (CGI-58) and other proteins of the lipid droplet surface are currently known to be key regulators of the lipolytic machinery, protecting or exposing the TAG core of the droplet to lipases. The neuroendocrine control of lipolysis is prototypically exerted by catecholaminergic stimulation and insulin-induced suppression, both of which affect cyclic AMP levels and hence the protein kinase A-mediated phosphorylation of HSL and perilipin. Interestingly, in recent decades adipose tissue has been shown to secrete a large number of adipokines, which exert direct effects on lipolysis, while adipocytes reportedly express a wide range of receptors for signals involved in lipid mobilisation. Recently recognised mediators of lipolysis include some adipokines, structural membrane proteins, atrial natriuretic peptides, AMP-activated protein kinase and mitogen-activated protein kinase. Lipolysis needs to be reanalysed from the broader perspective of its specific physiological or pathological context since basal or stimulated lipolytic rates occur under diverse conditions and by different mechanisms.
Collapse
|
345
|
Gherzi R, Chen CY, Ramos A, Briata P. KSRP controls pleiotropic cellular functions. Semin Cell Dev Biol 2014; 34:2-8. [PMID: 24845017 DOI: 10.1016/j.semcdb.2014.05.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 05/09/2014] [Accepted: 05/12/2014] [Indexed: 01/12/2023]
Abstract
The single-strand-RNA binding protein KSRP is able to negatively regulate gene expression operating with at least two distinct and integrated postranscriptional mechanisms: (i) by promoting decay of unstable mRNAs and (ii) by favoring maturation from precursors of select microRNAs (miRNAs) including the prototypical tumor suppressor let-7. Studies performed in primary and cultured cells as well as in mice proved that the ability of KSRP to integrate different levels of gene expression is required for proper immune response, lipid metabolism, cell-fate decisions, tissue regeneration, and DNA damage response.
Collapse
Affiliation(s)
- Roberto Gherzi
- Gene Expression Regulation Laboratory, IRCCS Azienda Ospedaliera Universitaria San Martino-IST, 16132 Genova, Italy.
| | - Ching-Yi Chen
- Department of Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Andres Ramos
- Molecular Structure Division, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Paola Briata
- Gene Expression Regulation Laboratory, IRCCS Azienda Ospedaliera Universitaria San Martino-IST, 16132 Genova, Italy.
| |
Collapse
|
346
|
Faylon M, Koltes D, Spurlock D. Regulation of lipid droplet-associated proteins following growth hormone administration and feed restriction in lactating Holstein cows. J Dairy Sci 2014; 97:2847-55. [DOI: 10.3168/jds.2013-7565] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 02/05/2014] [Indexed: 11/19/2022]
|
347
|
Kim SO, Sakchaisri K, Asami Y, Ryoo IJ, Choo SJ, Yoo ID, Soung NK, Kim YS, Jang JH, Kim BY, Ahn JS. Illudins C2 and C3 stimulate lipolysis in 3T3-L1 adipocytes and suppress adipogenesis in 3T3-L1 preadipocytes. JOURNAL OF NATURAL PRODUCTS 2014; 77:744-750. [PMID: 24597820 DOI: 10.1021/np400520a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The secondary metabolites illudins C2 (1) and C3 (2), obtained from the culture broth of Coprinus atramentarius, have been shown to possess antimicrobial activity. In the present study, we discovered novel biological activities of 1 and 2 in lipolysis of differentiated 3T3-L1 adipocytes and adipogenesis of 3T3-L1 preadipocytes. Compounds 1 and 2 exhibit a dose-dependent increase in glycerol release and thereby reduce intracellular lipid accumulation. The stimulatory effects of 1 and 2 on lipolysis are prevented by cAMP-dependent protein kinase (PKA) and extracellular signal-regulated kinase (ERK) inhibitors. Compounds 1 and 2 down-regulated perilipin and also affected the mRNA and protein levels of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL). However, 1 and 2 treatment leads to a significant increase in PKA-mediated phosphorylation of HSL at S563 and S660. In addition, 1 and 2 treatment in 3T3-L1 preadipocytes induces down-regulation of the critical transcription factors, CCAAT/enhancer binding protein α and β (C/EBPα and C/EBPβ), and peroxisome proliferator activated receptor γ (PPARγ), which are required for adipogenesis, and accordingly inhibits adipogenesis. These results suggest that 1 and 2 might be useful for treating obesity due to their modulatory effects on fat by affecting adipocyte differentiation and fat mobilization.
Collapse
Affiliation(s)
- Sun-Ok Kim
- World Class Institute (WCI) Center, Korea Research Institute of Bioscience and Biotechnology , 30 Yeongudanjiro, Ochang, Cheongwon, Chungbuk 363-883, Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
348
|
Singh M, Kaur R, Lee MJ, Pickering RT, Sharma VM, Puri V, Kandror KV. Fat-specific protein 27 inhibits lipolysis by facilitating the inhibitory effect of transcription factor Egr1 on transcription of adipose triglyceride lipase. J Biol Chem 2014; 289:14481-7. [PMID: 24742676 DOI: 10.1074/jbc.c114.563080] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Lipolysis in fat tissue represents a major source of circulating fatty acids. Previously, we have found that lipolysis in adipocytes is controlled by early growth response transcription factor Egr1 that directly inhibits transcription of adipose triglyceride lipase, ATGL (Chakrabarti, P., Kim, J. Y., Singh, M., Shin, Y. K., Kim, J., Kumbrink, J., Wu, Y., Lee, M. J., Kirsch, K. H., Fried, S. K., and Kandror, K. V. (2013) Mol. Cell. Biol. 33, 3659-3666). Here we demonstrate that knockdown of the lipid droplet protein FSP27 (a.k.a. CIDEC) in human adipocytes increases expression of ATGL at the level of transcription, whereas overexpression of FSP27 has the opposite effect. FSP27 suppresses the activity of the ATGL promoter in vitro, and the proximal Egr1 binding site is responsible for this effect. FSP27 co-immunoprecipitates with Egr1 and increases its association with and inhibition of the ATGL promoter. Knockdown of Egr1 attenuates the inhibitory effect of FSP27. These results provide a new model of transcriptional regulation of ATGL.
Collapse
Affiliation(s)
- Maneet Singh
- From the Boston University School of Medicine, Boston, Massachusetts 02118
| | - Rajween Kaur
- From the Boston University School of Medicine, Boston, Massachusetts 02118
| | - Mi-Jeong Lee
- From the Boston University School of Medicine, Boston, Massachusetts 02118
| | - R Taylor Pickering
- From the Boston University School of Medicine, Boston, Massachusetts 02118
| | | | - Vishwajeet Puri
- From the Boston University School of Medicine, Boston, Massachusetts 02118
| | | |
Collapse
|
349
|
Papáčková Z, Cahová M. Important role of autophagy in regulation of metabolic processes in health, disease and aging. Physiol Res 2014; 63:409-20. [PMID: 24702497 DOI: 10.33549/physiolres.932684] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Autophagy is the basic catabolic mechanism that involves degradation of dysfunctional cellular components through the action of lysosome as well as supplying energy and compounds for the synthesis of essential biomacromolecules. This process enables cells to survive stress from the external environment like nutrient deprivation. Autophagy is important in the breakdown of proteins, carbohydrates and lipids as well. Furthermore, recent studies have shown that autophagy is critical in wide range of normal human physiological processes, and defective autophagy is associated with diverse diseases, including lysosomal storage disease, myopathies, neurodegeneration and various metabolic disorders. This review summarizes the most up-to-date findings on what role autophagy plays in metabolism.
Collapse
Affiliation(s)
- Z Papáčková
- Institute for Clinical and Experimental Medicine, Department of Metabolism and Diabetes, Prague, Czech Republic.
| | | |
Collapse
|
350
|
Aberdein N, Schweizer M, Ball D. Sodium acetate decreases phosphorylation of hormone sensitive lipase in isoproterenol-stimulated 3T3-L1 mature adipocytes. Adipocyte 2014; 3:121-5. [PMID: 24719785 DOI: 10.4161/adip.27936] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 01/12/2014] [Accepted: 01/21/2014] [Indexed: 12/26/2022] Open
Abstract
Lipolysis, the process of hydrolysis of stored triacylglycerol into glycerol and non-esterified fatty acids (NEFA), is reported to be reduced by short chain fatty acids (SCFA) but the mechanism of this inhibition is poorly understood. The aim of this study was to measure the phosphorylation at serine residue 563 of hormone sensitive lipase with and without exposure to sodium acetate. Using the 3T3-L1 cell line, we identified that stimulating the cells with isoproterenol increased phosphorylated hormone sensitive lipase (pHSL) expression by 60% compared with the basal state. In the presence of the SCFA acetate in stimulated cells, pHSL decreased by 15% compared with stimulated cells alone. These results were mirrored by the NEFA release from stimulated cells that had significantly decreased in the presence of sodium acetate after 60 min (from 0.53 µmol mg(-1) protein to 0.41 µmol mg(-1) protein, respectively, P = 0.004); and 180 min (1.73 µmol mg(-1) protein to 1.13 µmol mg(-1) protein, P = 0.020); however, treatment had no effect on glycerol release (P = 0.109). In conclusion, exposure to 4 mM acetate reduced the level of phosphorylation of HSL(SER563) in mature 3T3-L1 adipocytes and led to a significant reduction in NEFA release, although glycerol release was not affected.
Collapse
|