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Karalis T, Poulogiannis G. The Emerging Role of LPA as an Oncometabolite. Cells 2024; 13:629. [PMID: 38607068 PMCID: PMC11011573 DOI: 10.3390/cells13070629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/25/2024] [Accepted: 04/01/2024] [Indexed: 04/13/2024] Open
Abstract
Lysophosphatidic acid (LPA) is a phospholipid that displays potent signalling activities that are regulated in both an autocrine and paracrine manner. It can be found both extra- and intracellularly, where it interacts with different receptors to activate signalling pathways that regulate a plethora of cellular processes, including mitosis, proliferation and migration. LPA metabolism is complex, and its biosynthesis and catabolism are under tight control to ensure proper LPA levels in the body. In cancer patient specimens, LPA levels are frequently higher compared to those of healthy individuals and often correlate with poor responses and more aggressive disease. Accordingly, LPA, through promoting cancer cell migration and invasion, enhances the metastasis and dissemination of tumour cells. In this review, we summarise the role of LPA in the regulation of critical aspects of tumour biology and further discuss the available pre-clinical and clinical evidence regarding the feasibility and efficacy of targeting LPA metabolism for effective anticancer therapy.
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Affiliation(s)
| | - George Poulogiannis
- Signalling and Cancer Metabolism Laboratory, Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK;
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2
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Zhou Y, Little PJ, Cao Y, Ta HT, Kamato D. Lysophosphatidic acid receptor 5 transactivation of TGFBR1 stimulates the mRNA expression of proteoglycan synthesizing genes XYLT1 and CHST3. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2020; 1867:118848. [PMID: 32920014 DOI: 10.1016/j.bbamcr.2020.118848] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/30/2020] [Accepted: 09/03/2020] [Indexed: 12/27/2022]
Abstract
Lysophosphatidic acid (LPA) via transactivation dependent signalling pathways contributes to a plethora of physiological and pathophysiological responses. In the vasculature, hyperelongation of glycosaminoglycan (GAG) chains on proteoglycans leads to lipid retention in the intima resulting in the early pathogenesis of atherosclerosis. Therefore, we investigated and defined the contribution of transactivation dependent signalling in LPA mediated GAG chain hyperelongation in human vascular smooth muscle cells (VSMCs). LPA acting via the LPA receptor 5 (LPAR5) transactivates the TGFBR1 to stimulate the mRNA expression of GAG initiation and elongation genes xylosyltransferase-1 (XYLT1) and chondroitin 6-sulfotransferase-1 (CHST3), respectively. We found that LPA stimulates ROS and Akt signalling in VSMCs, however they are not associated in LPAR5 transactivation of the TGFBR1. We observed that LPA via ROCK dependent pathways transactivates the TGFBR1 to stimulate genes associated with GAG chain elongation. We demonstrate that GPCR transactivation of the TGFBR1 occurs via a universal biochemical mechanism and the identified effectors represent potential therapeutic targets to inhibit pathophysiological effects of GPCR transactivation of the TGFBR1.
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Affiliation(s)
- Ying Zhou
- School of Pharmacy, Pharmacy Australia Centre of Excellence, the University of Queensland, Woolloongabba, Queensland 4102, Australia.
| | - Peter J Little
- School of Pharmacy, Pharmacy Australia Centre of Excellence, the University of Queensland, Woolloongabba, Queensland 4102, Australia; Department of Pharmacy, Xinhua College of Sun Yat-sen University, Tianhe District, Guangzhou 510520, China.
| | - Yingnan Cao
- Department of Pharmacy, Xinhua College of Sun Yat-sen University, Tianhe District, Guangzhou 510520, China
| | - Hang T Ta
- School of Pharmacy, Pharmacy Australia Centre of Excellence, the University of Queensland, Woolloongabba, Queensland 4102, Australia; School of Environment and Science, Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, QLD 4111, Australia.
| | - Danielle Kamato
- School of Pharmacy, Pharmacy Australia Centre of Excellence, the University of Queensland, Woolloongabba, Queensland 4102, Australia; Department of Pharmacy, Xinhua College of Sun Yat-sen University, Tianhe District, Guangzhou 510520, China.
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3
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Funcke JB, Scherer PE. Beyond adiponectin and leptin: adipose tissue-derived mediators of inter-organ communication. J Lipid Res 2019; 60:1648-1684. [PMID: 31209153 PMCID: PMC6795086 DOI: 10.1194/jlr.r094060] [Citation(s) in RCA: 176] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/17/2019] [Indexed: 01/10/2023] Open
Abstract
The breakthrough discoveries of leptin and adiponectin more than two decades ago led to a widespread recognition of adipose tissue as an endocrine organ. Many more adipose tissue-secreted signaling mediators (adipokines) have been identified since then, and much has been learned about how adipose tissue communicates with other organs of the body to maintain systemic homeostasis. Beyond proteins, additional factors, such as lipids, metabolites, noncoding RNAs, and extracellular vesicles (EVs), released by adipose tissue participate in this process. Here, we review the diverse signaling mediators and mechanisms adipose tissue utilizes to relay information to other organs. We discuss recently identified adipokines (proteins, lipids, and metabolites) and briefly outline the contributions of noncoding RNAs and EVs to the ever-increasing complexities of adipose tissue inter-organ communication. We conclude by reflecting on central aspects of adipokine biology, namely, the contribution of distinct adipose tissue depots and cell types to adipokine secretion, the phenomenon of adipokine resistance, and the capacity of adipose tissue to act both as a source and sink of signaling mediators.
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Affiliation(s)
- Jan-Bernd Funcke
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
| | - Philipp E Scherer
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
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4
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Yang F, Chen GX. Production of extracellular lysophosphatidic acid in the regulation of adipocyte functions and liver fibrosis. World J Gastroenterol 2018; 24:4132-4151. [PMID: 30271079 PMCID: PMC6158478 DOI: 10.3748/wjg.v24.i36.4132] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 04/24/2018] [Accepted: 05/05/2018] [Indexed: 02/06/2023] Open
Abstract
Lysophosphatidic acid (LPA), a glycerophospholipid, consists of a glycerol backbone connected to a phosphate head group and an acyl chain linked to sn-1 or sn-2 position. In the circulation, LPA is in sub-millimolar range and mainly derived from hydrolysis of lysophosphatidylcholine, a process mediated by lysophospholipase D activity in proteins such as autotaxin (ATX). Intracellular and extracellular LPAs act as bioactive lipid mediators with diverse functions in almost every mammalian cell type. The binding of LPA to its receptors LPA1-6 activates multiple cellular processes such as migration, proliferation and survival. The production of LPA and activation of LPA receptor signaling pathways in the events of physiology and pathophysiology have attracted the interest of researchers. Results from studies using transgenic and gene knockout animals with alterations of ATX and LPA receptors genes, have revealed the roles of LPA signaling pathways in metabolic active tissues and organs. The present review was aimed to summarize recent progresses in the studies of extracellular and intracellular LPA production pathways. This includes the functional, structural and biochemical properties of ATX and LPA receptors. The potential roles of LPA production and LPA receptor signaling pathways in obesity, insulin resistance and liver fibrosis are also discussed.
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Affiliation(s)
- Fang Yang
- School of Laboratory Medicine, Hubei University of Chinese Medicine, Wuhan 430065, Hubei Province, China
| | - Guo-Xun Chen
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, United States
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5
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Nedergaard J, Wang Y, Cannon B. Cell proliferation and apoptosis inhibition: essential processes for recruitment of the full thermogenic capacity of brown adipose tissue. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:51-58. [PMID: 29908367 DOI: 10.1016/j.bbalip.2018.06.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 05/15/2018] [Accepted: 06/11/2018] [Indexed: 12/20/2022]
Abstract
In mice living under normal animal house conditions, the brown adipocytes in classical brown adipose tissue depots are already essentially fully differentiated: UCP1 mRNA and UCP1 protein levels are practically saturated. This means that any further recruitment - in response to cold exposure or any other browning agent - does not result in significant augmentation of these parameters. This may easily be construed to indicate that classical brown adipose tissue cannot be further recruited. However, this is far from the case: the capacity for further recruitment instead lies in the ability of the tissue to increase the number of brown-fat cells, a remarkable and highly controlled physiological recruitment process. We have compiled here the available data concerning the unique ability of norepinephrine to increase cell proliferation and inhibit apoptosis in brown adipocytes. Adrenergically stimulated cell proliferation is fully mediated via β1-adrenoceptors and occurs through activation of stem cells in the tissue; intracellular mediation of the signal involves cAMP and protein kinase A activation, but activation of Erk1/2 is not part of the pathway. Apoptosis inhibition in brown adipocytes is induced by both β- and α1-adrenergic receptors and here the intracellular pathway includes Erk1/2 activation. This unique ability of norepinephrine to increase cell number in an apparently mitogenically dormant tissue provides possibilities to augment the metabolic capacity of brown adipose tissue, also for therapeutic purposes.
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Affiliation(s)
- Jan Nedergaard
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden.
| | - Yanling Wang
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Barbara Cannon
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
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6
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D'Souza K, Paramel GV, Kienesberger PC. Lysophosphatidic Acid Signaling in Obesity and Insulin Resistance. Nutrients 2018; 10:nu10040399. [PMID: 29570618 PMCID: PMC5946184 DOI: 10.3390/nu10040399] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 03/13/2018] [Accepted: 03/20/2018] [Indexed: 12/21/2022] Open
Abstract
Although simple in structure, lysophosphatidic acid (LPA) is a potent bioactive lipid that profoundly influences cellular signaling and function upon binding to G protein-coupled receptors (LPA1-6). The majority of circulating LPA is produced by the secreted enzyme autotaxin (ATX). Alterations in LPA signaling, in conjunction with changes in autotaxin (ATX) expression and activity, have been implicated in metabolic and inflammatory disorders including obesity, insulin resistance, and cardiovascular disease. This review summarizes our current understanding of the sources and metabolism of LPA with focus on the influence of diet on circulating LPA. Furthermore, we explore how the ATX-LPA pathway impacts obesity and obesity-associated disorders, including impaired glucose homeostasis, insulin resistance, and cardiovascular disease.
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Affiliation(s)
- Kenneth D'Souza
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, NB, E2L 4L5 Canada.
| | - Geena V Paramel
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, NB, E2L 4L5 Canada.
| | - Petra C Kienesberger
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, NB, E2L 4L5 Canada.
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7
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Tveteraas IH, Aasrum M, Brusevold IJ, Ødegård J, Christoffersen T, Sandnes D. Lysophosphatidic acid induces both EGFR-dependent and EGFR-independent effects on DNA synthesis and migration in pancreatic and colorectal carcinoma cells. Tumour Biol 2015; 37:2519-26. [DOI: 10.1007/s13277-015-4010-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 08/27/2015] [Indexed: 12/19/2022] Open
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8
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Abstract
Lysophosphatidic acid (LPA) is a bioactive phospholipid that is present in all tissues examined to date. LPA signals extracellularly via cognate G protein-coupled receptors to mediate cellular processes such as survival, proliferation, differentiation, migration, adhesion and morphology. These LPA-influenced processes impact many aspects of organismal development. In particular, LPA signalling has been shown to affect fertility and reproduction, formation of the nervous system, and development of the vasculature. Here and in the accompanying poster, we review the developmentally related features of LPA signalling.
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Affiliation(s)
- Xiaoyan Sheng
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yun C Yung
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Allison Chen
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jerold Chun
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
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9
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Llona-Minguez S, Ghassemian A, Helleday T. Lysophosphatidic acid receptor (LPAR) modulators: The current pharmacological toolbox. Prog Lipid Res 2015; 58:51-75. [DOI: 10.1016/j.plipres.2015.01.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 01/15/2015] [Accepted: 01/20/2015] [Indexed: 12/17/2022]
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10
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Yung YC, Stoddard NC, Chun J. LPA receptor signaling: pharmacology, physiology, and pathophysiology. J Lipid Res 2014; 55:1192-214. [PMID: 24643338 DOI: 10.1194/jlr.r046458] [Citation(s) in RCA: 517] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Indexed: 12/18/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a small ubiquitous lipid found in vertebrate and nonvertebrate organisms that mediates diverse biological actions and demonstrates medicinal relevance. LPA's functional roles are driven by extracellular signaling through at least six 7-transmembrane G protein-coupled receptors. These receptors are named LPA1-6 and signal through numerous effector pathways activated by heterotrimeric G proteins, including Gi/o, G12/13, Gq, and Gs LPA receptor-mediated effects have been described in numerous cell types and model systems, both in vitro and in vivo, through gain- and loss-of-function studies. These studies have revealed physiological and pathophysiological influences on virtually every organ system and developmental stage of an organism. These include the nervous, cardiovascular, reproductive, and pulmonary systems. Disturbances in normal LPA signaling may contribute to a range of diseases, including neurodevelopmental and neuropsychiatric disorders, pain, cardiovascular disease, bone disorders, fibrosis, cancer, infertility, and obesity. These studies underscore the potential of LPA receptor subtypes and related signaling mechanisms to provide novel therapeutic targets.
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Affiliation(s)
- Yun C Yung
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037
| | - Nicole C Stoddard
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037 Biomedical Sciences Graduate Program, University of California, San Diego School of Medicine, La Jolla, CA 92037
| | - Jerold Chun
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037
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11
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In brown adipocytes, adrenergically induced β1-/β3-(Gs)-, α2-(Gi)- and α1-(Gq)-signalling to Erk1/2 activation is not mediated via EGF receptor transactivation. Exp Cell Res 2013; 319:2718-27. [DOI: 10.1016/j.yexcr.2013.08.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 08/02/2013] [Accepted: 08/05/2013] [Indexed: 11/15/2022]
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12
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Rancoule C, Dusaulcy R, Tréguer K, Grès S, Attané C, Saulnier-Blache JS. Involvement of autotaxin/lysophosphatidic acid signaling in obesity and impaired glucose homeostasis. Biochimie 2013; 96:140-3. [PMID: 23639740 DOI: 10.1016/j.biochi.2013.04.010] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 04/11/2013] [Indexed: 12/11/2022]
Abstract
Autotaxin (ATX) is a secreted lysophospholipase D involved in synthesis of lysophosphatidic acid (LPA), a phospholipid growth factor acting via specific receptors (LPA1R to LPA6R) and involved in several pathologies including obesity. ATX is secreted by adipocytes and contributes to circulating LPA. ATX expression is up-regulated in obese patients and mice in relationship with insulin resistance and impaired glucose tolerance. LPA1R is the most abundant subtype in adipose tissue. Its expression is higher in non-adipocyte cells than in adipocytes and is not altered in obesity. ATX increases and LPA1R decreases while preadipocytes differentiate into adipocytes (adipogenesis). LPA inhibits adipogenesis through down-regulation of the pro-adipogenic transcription factor PPARγ2. Adipocyte-specific knockout (FATX-KO) mice or mice treated with the LPAR antagonist Ki16425 gain more weight and accumulate more adipose tissue than wild type or control mice fed a high fat diet (HFD). These observations suggest that LPA (via LPA1R) exerts a tonic inhibitory effect on adipose tissue expansion that could, at least in part, result from the anti-adipogenic activity of LPA. A possible negative impact of LPA on insulin-sensitivity might also be considered. Despite being more sensitive to nutritional obesity, FATX-KO and Ki16425-treated mice fed a HFD show improved glucose tolerance when compared to wild type mice. Moreover, exogenously injected LPA acutely impairs glucose tolerance and insulin secretion. These observations show that LPA exerts a tonic deleterious impact on glucose homeostasis. In conclusion, ATX and LPA1R represent potential interesting pharmacological targets for the treatment of obesity-associated metabolic diseases.
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Affiliation(s)
- Chloé Rancoule
- Institut des maladies métaboliques et cardiovasculaires (I2MC), Inserm U1048. Université Paul Sabatier, Toulouse, France
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Federico L, Ren H, Mueller PA, Wu T, Liu S, Popovic J, Blalock EM, Sunkara M, Ovaa H, Albers HM, Mills GB, Morris AJ, Smyth SS. Autotaxin and its product lysophosphatidic acid suppress brown adipose differentiation and promote diet-induced obesity in mice. Mol Endocrinol 2012; 26:786-97. [PMID: 22474126 DOI: 10.1210/me.2011-1229] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Brown adipose tissue is a thermogenic organ that dissipates stored energy as heat to maintain body temperature. This process may also provide protection from development of diet-induced obesity. We report that the bioactive lipid mediator lysophosphatidic acid (LPA) markedly decreases differentiation of cultured primary brown adipocyte precursors, whereas potent selective inhibitors of the LPA-generating enzyme autotaxin (ATX) promote differentiation. Transgenic mice overexpressing ATX exhibit reduced expression of brown adipose tissue-related genes in peripheral white adipose tissue and accumulate significantly more fat than wild-type controls when fed a high-fat diet. Our results indicate that ATX and its product LPA are physiologically relevant negative regulators of brown fat adipogenesis and are consistent with a model in which a decrease in mature peripheral brown adipose tissue results in increased susceptibility to diet-induced obesity in mice.
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Affiliation(s)
- Lorenzo Federico
- Division of Cardiovascular Medicine, University of Kentucky, Lexington, Kentucky 40536, USA
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14
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Mattsson CL, Csikasz RI, Chernogubova E, Yamamoto DL, Hogberg HT, Amri EZ, Hutchinson DS, Bengtsson T. β₁-Adrenergic receptors increase UCP1 in human MADS brown adipocytes and rescue cold-acclimated β₃-adrenergic receptor-knockout mice via nonshivering thermogenesis. Am J Physiol Endocrinol Metab 2011; 301:E1108-18. [PMID: 21878665 DOI: 10.1152/ajpendo.00085.2011] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
With the finding that brown adipose tissue is present and negatively correlated to obesity in adult man, finding the mechanism(s) of how to activate brown adipose tissue in humans could be important in combating obesity, type 2 diabetes, and their complications. In mice, the main regulator of nonshivering thermogenesis in brown adipose tissue is norepinephrine acting predominantly via β(3)-adrenergic receptors. However, vast majorities of β(3)-adrenergic agonists have so far not been able to stimulate human β(3)-adrenergic receptors or brown adipose tissue activity, and it was postulated that human brown adipose tissue could be regulated instead by β(1)-adrenergic receptors. Therefore, we have investigated the signaling pathways, specifically pathways to nonshivering thermogenesis, in mice lacking β(3)-adrenergic receptors. Wild-type and β(3)-knockout mice were either exposed to acute cold (up to 12 h) or acclimated for 7 wk to cold, and parameters related to metabolism and brown adipose tissue function were investigated. β(3)-knockout mice were able to survive both acute and prolonged cold exposure due to activation of β(1)-adrenergic receptors. Thus, in the absence of β(3)-adrenergic receptors, β(1)-adrenergic receptors are effectively able to signal via cAMP to elicit cAMP-mediated responses and to recruit and activate brown adipose tissue. In addition, we found that in human multipotent adipose-derived stem cells differentiated into functional brown adipocytes, activation of either β(1)-adrenergic receptors or β(3)-adrenergic receptors was able to increase UCP1 mRNA and protein levels. Thus, in humans, β(1)-adrenergic receptors could play an important role in regulating nonshivering thermogenesis.
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MESH Headings
- Acclimatization/genetics
- Acclimatization/physiology
- Adipocytes, Brown/cytology
- Adipocytes, Brown/metabolism
- Animals
- Cell Differentiation/genetics
- Cell Differentiation/physiology
- Cells, Cultured
- Cold Temperature
- Down-Regulation/genetics
- Epistasis, Genetic/physiology
- Female
- Humans
- Ion Channels/genetics
- Ion Channels/metabolism
- Male
- Mice
- Mice, Knockout
- Mitochondrial Proteins/genetics
- Mitochondrial Proteins/metabolism
- Multipotent Stem Cells/cytology
- Multipotent Stem Cells/metabolism
- Receptors, Adrenergic, beta-1/genetics
- Receptors, Adrenergic, beta-1/metabolism
- Receptors, Adrenergic, beta-1/physiology
- Receptors, Adrenergic, beta-3/genetics
- Shivering/genetics
- Shivering/physiology
- Thermogenesis/genetics
- Thermogenesis/physiology
- Uncoupling Protein 1
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Affiliation(s)
- Charlotte L Mattsson
- Department of Physiology, The Wenner-Gren Institute, Arrhenius Laboratories F3, Stockholm University, Stockholm, Sweden
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15
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Djordjevic JT. Role of phospholipases in fungal fitness, pathogenicity, and drug development - lessons from cryptococcus neoformans. Front Microbiol 2010; 1:125. [PMID: 21687772 PMCID: PMC3109512 DOI: 10.3389/fmicb.2010.00125] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 10/25/2010] [Indexed: 11/13/2022] Open
Abstract
Many pathogenic microbes, including many fungi, produce phospholipases which facilitate survival of the pathogen in vivo, invasion and dissemination throughout the host, expression of virulence traits and evasion of host immune defense mechanisms. These phospholipases are either secreted or produced intracellularly and act by physically disrupting host membranes, and/or by affecting fungal cell signaling and production of immunomodulatory effectors. Many of the secreted phospholipases acquire a glycosylphosphatidylinositol sorting motif to facilitate membrane and/or cell wall association and secretion. This review focuses primarily on the role of two members of the phospholipase enzyme family, phospholipase B (Plb) and phosphatidylinositol (PI)-specific phospholipase C (PI-C/Plc), in fungal pathogenesis and in particular, what has been learnt about their function from studies performed in the model pathogenic yeast, Cryptococcus neoformans. These studies have revealed how Plb has adapted to become an important part of the virulence repertoire of pathogenic fungi and how its secretion is regulated. They have also provided valuable insight into how the intracellular enzyme, Plc1, contributes to fungal fitness and pathogenicity – via a putative role in signal transduction pathways that regulate the production of stress-protecting pigments, polysaccharide capsule, cell wall integrity, and adaptation to growth at host temperature. Finally, this review will address the role fungal phospholipases have played in the development of a new class of antifungal drugs, which mimic their phospholipid substrates.
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Affiliation(s)
- Julianne Teresa Djordjevic
- Fungal Pathogenesis Laboratory, Centre for Infectious Diseases and Microbiology, Sydney Medical School-Western, Westmead Millennium Institute, University of Sydney at Westmead Hospital Westmead, NSW, Australia
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