201
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Strodthoff D, Lundberg AM, Agardh HE, Ketelhuth DFJ, Paulsson-Berne G, Arner P, Hansson GK, Gerdes N. Lack of invariant natural killer T cells affects lipid metabolism in adipose tissue of diet-induced obese mice. Arterioscler Thromb Vasc Biol 2013; 33:1189-96. [PMID: 23520162 DOI: 10.1161/atvbaha.112.301105] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Obesity promotes a chronic inflammatory condition in adipose tissue (AT). Impairment of insulin sensitivity coincides with infiltration of T cells into AT in early stages of obesity, when macrophages are not yet present. Here, we examine the role of invariant natural killer T (iNKT) cells, a subtype of T cells activated by lipid antigens, on glucose and lipid metabolism in obesity. APPROACH AND RESULTS Jα18(-/-) mice, specifically lacking iNKT cells, and wild-type mice consumed a chow or high-fat diet for 10 weeks. One third of all T lymphocytes in the liver of wild-type mice were iNKT cells, whereas few were detected in AT. Diet-induced obesity increased blood glucose in both genotypes of mice, whereas glucose tolerance test revealed similar kinetics of glucose clearance in Jα18(-/-) and wild-type mice. Under obese conditions, expression of inflammatory cytokines in AT did not differ between the groups, although the number of T cells and macrophages was lower in Jα18(-/-) mice. Nonetheless, AT homeostasis in Jα18(-/-) mice was altered evidenced by lower AT weight, smaller adipocytes, accelerated lipogenesis, increased expression of hormone-sensitive lipase, and accelerated basal lipolysis. CONCLUSIONS iNKT cells do not affect glucose clearance but rather modulate lipid metabolism in both liver and AT. Only few iNKT cells are found in AT under lean and obese conditions, suggesting that their effects on lipid metabolism are mainly mediated in the liver, their primary host organ.
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Affiliation(s)
- Daniela Strodthoff
- Department of Medicine, Center for Molecular Medicine, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
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202
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Korytowski W, Pilat A, Schmitt JC, Girotti AW. Deleterious cholesterol hydroperoxide trafficking in steroidogenic acute regulatory (StAR) protein-expressing MA-10 Leydig cells: implications for oxidative stress-impaired steroidogenesis. J Biol Chem 2013; 288:11509-19. [PMID: 23467407 DOI: 10.1074/jbc.m113.452151] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Steroidogenic acute regulatory (StAR) proteins in steroidogenic cells are implicated in the delivery of cholesterol (Ch) from internal or external sources to mitochondria (Mito) for initiation of steroid hormone synthesis. In this study, we tested the hypothesis that under oxidative stress, StAR-mediated trafficking of redox-active cholesterol hydroperoxides (ChOOHs) can result in site-specific Mito damage and dysfunction. Steroidogenic stimulation of mouse MA-10 Leydig cells with dibutyryl-cAMP (Bt2cAMP) resulted in strong expression of StarD1 and StarD4 proteins over insignificant levels in nonstimulated controls. During incubation with the ChOOH 3β-hydroxycholest-5-ene-7α-hydroperoxide (7α-OOH) in liposomes, stimulated cells took up substantially more hydroperoxide in Mito than controls, with a resulting loss of membrane potential (ΔΨm) and ability to drive progesterone synthesis. 7α-OOH uptake and ΔΨm loss were greatly reduced by StarD1 knockdown, thus establishing the role of this protein in 7α-OOH delivery. Moreover, 7α-OOH was substantially more toxic to stimulated than nonstimulated cells, the former dying mainly by apoptosis and the latter dying by necrosis. Importantly, tert-butyl hydroperoxide, which is not a StAR protein ligand, was equally toxic to stimulated and nonstimulated cells. These findings support the notion that like Ch itself, 7α-OOH can be transported to/into Mito of steroidogenic cells by StAR proteins and therein induce free radical damage, which compromises steroid hormone synthesis.
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Affiliation(s)
- Witold Korytowski
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
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203
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Casado ME, Pastor O, Mariscal P, Canfrán-Duque A, Martínez-Botas J, Kraemer FB, Lasunción MA, Martín-Hidalgo A, Busto R. Hormone-sensitive lipase deficiency disturbs the fatty acid composition of mouse testis. Prostaglandins Leukot Essent Fatty Acids 2013; 88:227-33. [PMID: 23369366 DOI: 10.1016/j.plefa.2012.12.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 12/12/2012] [Accepted: 12/15/2012] [Indexed: 10/27/2022]
Abstract
Hormone-sensitive lipase (HSL) is a key enzyme in the mobilization of fatty acids from intracellular stores. In mice, HSL deficiency results in male sterility caused by a major defect in spermatogenesis. The testes contain high concentrations of PUFA and specific PUFA are essential for spermatogenesis. We investigated the fatty acid composition and the mRNA levels of key enzymes involved in fatty acid metabolism in testis of HSL-knockout mice. HSL deficiency altered fatty acid composition in the testis but not in plasma. The most important changes were decreases in the essential n-6 PUFA LNA and the n-3 PUFA ALA, and an increase in the corresponding synthesis intermediates C22:4n-6 and C22:5n-3 without changes in DPAn-6 or DHA acids. Mead acid, which has been associated with an essential fatty acid deficit leading to male infertility, was increased in the testis from HSL-knockout mice. Moreover, the expression of SCD-1, FADS1, and FADS2 was increased while expression of ELOVL2, an essential enzyme for the formation of very-long PUFA in testis, was decreased. Given the indispensability of these fatty acids for spermatogenesis, the changes in fatty acid metabolism observed in testes from HSL-knockout male mice may underlie the infertility of these animals.
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Affiliation(s)
- M E Casado
- Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria (IRyCIS), E-28034 Madrid, Spain
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204
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Pereira MJ, Palming J, Rizell M, Aureliano M, Carvalho E, Svensson MK, Eriksson JW. The immunosuppressive agents rapamycin, cyclosporin A and tacrolimus increase lipolysis, inhibit lipid storage and alter expression of genes involved in lipid metabolism in human adipose tissue. Mol Cell Endocrinol 2013; 365:260-9. [PMID: 23160140 DOI: 10.1016/j.mce.2012.10.030] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 10/15/2012] [Accepted: 10/30/2012] [Indexed: 02/07/2023]
Abstract
Cyclosporin A (CsA), tacrolimus and rapamycin are immunosuppressive agents (IAs) associated with insulin resistance and dyslipidemia, although their molecular effects on lipid metabolism in adipose tissue are unknown. We explored IAs effects on lipolysis, lipid storage and expression of genes involved on lipid metabolism in isolated human adipocytes and/or adipose tissue obtained via subcutaneous and omental fat biopsies. CsA, tacrolimus and rapamycin increased isoproterenol-stimulated lipolysis and inhibited lipid storage by 20-35% and enhanced isoproterenol-stimulated hormone-sensitive lipase Ser552 phosphorylation. Rapamycin also increased basal lipolysis (~20%) and impaired insulin's antilipolytic effect. Rapamycin, down-regulated the gene expression of perilipin, sterol regulatory element-binding protein 1 (SREBP1) and lipin 1, while tacrolimus down-regulated CD36 and aP2 gene expression. All three IAs increased IL-6 gene expression and secretion, but not expression and secretion of TNF-α or adiponectin. These findings suggest that CsA, tacrolimus and rapamycin enhance lipolysis, inhibit lipid storage and expression of lipogenic genes in adipose tissue, which may contribute to the development of dyslipidemia and insulin resistance associated with immunosuppressive therapy.
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Affiliation(s)
- Maria J Pereira
- The Lundberg Laboratory for Diabetes Research, Department of Molecular and Clinical Medicine, The Sahlgrenska Academy at University of Gothenburg, 413 45 Gothenburg, Sweden.
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205
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Obstructive sleep apnea and dyslipidemia: pathophysiological mechanisms. Sleep Breath 2012; 17:445. [DOI: 10.1007/s11325-012-0773-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 10/03/2012] [Indexed: 11/26/2022]
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206
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Casado ME, Huerta L, Ortiz AI, Pérez-Crespo M, Gutiérrez-Adán A, Kraemer FB, Lasunción MÁ, Busto R, Martín-Hidalgo A. HSL-knockout mouse testis exhibits class B scavenger receptor upregulation and disrupted lipid raft microdomains. J Lipid Res 2012; 53:2586-97. [PMID: 22988039 DOI: 10.1194/jlr.m028076] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
There is a tight relationship between fertility and changes in cholesterol metabolism during spermatogenesis. In the testis, class B scavenger receptors (SR-B) SR-BI, SR-BII, and LIMP II mediate the selective uptake of cholesterol esters from HDL, which are hydrolyzed to unesterified cholesterol by hormone-sensitive lipase (HSL). HSL is critical because HSL knockout (KO) male mice are sterile. The aim of the present work was to determine the effects of the lack of HSL in testis on the expression of SR-B, lipid raft composition, and related cell signaling pathways. HSL-KO mouse testis presented altered spermatogenesis associated with decreased sperm counts, sperm motility, and infertility. In wild-type (WT) testis, HSL is expressed in elongated spermatids; SR-BI, in Leydig cells and spermatids; SR-BII, in spermatocytes and spermatids but not in Leydig cells; and LIMP II, in Sertoli and Leydig cells. HSL knockout male mice have increased expression of class B scavenger receptors, disrupted caveolin-1 localization in lipid raft plasma membrane microdomains, and activated phospho-ERK, phospho-AKT, and phospho-SRC in the testis, suggesting that class B scavenger receptors are involved in cholesterol ester uptake for steroidogenesis and spermatogenesis in the testis.
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Affiliation(s)
- María Emilia Casado
- Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria, Madrid, Spain
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207
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Morak M, Schmidinger H, Riesenhuber G, Rechberger GN, Kollroser M, Haemmerle G, Zechner R, Kronenberg F, Hermetter A. Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) deficiencies affect expression of lipolytic activities in mouse adipose tissues. Mol Cell Proteomics 2012; 11:1777-89. [PMID: 22984285 DOI: 10.1074/mcp.m111.015743] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) are key enzymes involved in intracellular degradation of triacylglycerols. It was the aim of this study to elucidate how the deficiency in one of these proteins affects the residual lipolytic proteome in adipose tissue. For this purpose, we compared the lipase patterns of brown and white adipose tissue from ATGL (-/-) and HSL (-/-) mice using differential activity-based gel electrophoresis. This method is based on activity-recognition probes possessing the same substrate analogous structure but carrying different fluorophores for specific detection of the enzyme patterns of two different tissues in one electrophoresis gel. We found that ATGL-deficiency in brown adipose tissue had a profound effect on the expression levels of other lipolytic and esterolytic enzymes in this tissue, whereas HSL-deficiency hardly showed any effect in brown adipose tissue. Neither ATGL- nor HSL-deficiency greatly influenced the lipase patterns in white adipose tissue. Enzyme activities of mouse tissues on acylglycerol substrates were analyzed as well, showing that ATGL-and HSL-deficiencies can be compensated for at least in part by other enzymes. The proteins that responded to ATGL-deficiency in brown adipose tissue were overexpressed and their activities on acylglycerols were analyzed. Among these enzymes, Es1, Es10, and Es31-like represent lipase candidates as they catalyze the hydrolysis of long-chain acylglycerols.
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Affiliation(s)
- Maria Morak
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
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208
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Lee JH, Moon MH, Jeong JK, Park YG, Lee YJ, Seol JW, Park SY. Sulforaphane induced adipolysis via hormone sensitive lipase activation, regulated by AMPK signaling pathway. Biochem Biophys Res Commun 2012; 426:492-7. [PMID: 22982310 DOI: 10.1016/j.bbrc.2012.08.107] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 08/22/2012] [Indexed: 10/27/2022]
Abstract
Sulforaphane, an aliphatic isothiocyanate derived from cruciferous vegetables, is known for its antidiabetic properties. The effects of sulforaphane on lipid metabolism in adipocytes are not clearly understood. Here, we investigated whether sulforaphane stimulates lipolysis. Mature adipocytes were incubated with sulforaphane for 24h and analyzed using a lipolysis assay which quantified glycerol released into the medium. We investigated gene expression of hormone-sensitive lipase (HSL), and levels of HSL phosphorylation and AMP-activated protein kinase on sulforaphane-mediated lipolysis in adipocytes. Sulforaphane promoted lipolysis and increased both HSL gene expression and HSL activation. Sulforaphane suppressed AMPK phosphorylation at Thr-172 in a dose-dependent manner, which was associated with a decrease in HSL phosphorylation at Ser-565, enhancing the phosphorylation of HSL Ser-563. Taken together, these results suggest that sulforaphane promotes lipolysis via hormone sensitive lipase activation mediated by decreasing AMPK signal activation in adipocytes.
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Affiliation(s)
- Ju-Hee Lee
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561 756, South Korea
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209
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Wang F, Vihma V, Badeau M, Savolainen-Peltonen H, Leidenius M, Mikkola T, Turpeinen U, Hämäläinen E, Ikonen E, Wähälä K, Fledelius C, Jauhiainen M, Tikkanen MJ. Fatty acyl esterification and deesterification of 17β-estradiol in human breast subcutaneous adipose tissue. J Clin Endocrinol Metab 2012; 97:3349-56. [PMID: 22723316 DOI: 10.1210/jc.2012-1762] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
CONTEXT Adipose tissue has an important role in peripheral estrogen synthesis. One of the metabolic pathways of estradiol (E(2)) is its conversion to lipophilic fatty acyl esters. OBJECTIVE The aim was to study the metabolism of E(2) fatty acyl esters in adipose tissue and, specifically, the role of hormone-sensitive lipase (HSL) in steroid ester hydrolysis. DESIGN AND SETTING Tissue samples were obtained during elective surgery in University Central Hospital in the years 2008-2011. PATIENTS Women undergoing reduction mammoplasty (n = 27) or surgery for breast cancer (n = 16) participated in the study. INTERVENTIONS Two sc adipose tissue samples were taken from different quadrants of the breast. Radiolabeled steroids were incubated with tissue homogenate (esterase assay) or microsomal fraction (acyl transferase assay). E(2) and E(2) fatty acyl ester concentrations were determined by fluoroimmunoassay or liquid chromatography-tandem mass spectrometry. MAIN OUTCOME MEASURES We evaluated the hydrolysis rate of E(2) fatty acyl esters as well as the esterification rate of E(2); we also related tissue concentrations of E(2) and E(2) esters to serum estrogen concentrations. RESULTS Compared to esters of dehydroepiandrosterone and cholesterol, the hydrolysis of E(2) esters was much slower, whereas the esterification rate of E(2) was higher. The hydrolysis of E(2) esters in adipose tissue was reduced by 33-51% by inhibition of HSL. Estrogen concentration in sc adipose tissue was higher than in serum in both pre- and postmenopausal women. CONCLUSIONS E(2) fatty acyl esters in adipose tissue surrounding the mammary gland may act as a reservoir for conversion back to biologically active E(2). This is partly dependent on HSL activity.
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Affiliation(s)
- Feng Wang
- Folkhälsan Research Center, Biomedicum Helsinki C415, Haartmaninkatu 8, 00290 Helsinki, Finland
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210
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Feingold KR, Shigenaga JK, Kazemi MR, McDonald CM, Patzek SM, Cross AS, Moser A, Grunfeld C. Mechanisms of triglyceride accumulation in activated macrophages. J Leukoc Biol 2012; 92:829-39. [PMID: 22753953 DOI: 10.1189/jlb.1111537] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
LPS treatment of macrophages induces TG accumulation, which is accentuated by TG-rich lipoproteins or FFA. We defined pathways altered during macrophage activation that contribute to TG accumulation. Glucose uptake increased with activation, accompanied by increased GLUT1. Oxidation of glucose markedly decreased, whereas incorporation of glucose-derived carbon into FA and sterols increased. Macrophage activation also increased uptake of FFA, associated with an increase in CD36. Oxidation of FA was markedly reduced, whereas the incorporation of FA into TGs increased, associated with increased GPAT3 and DGAT2. Additionally, macrophage activation decreased TG lipolysis; however, expression of ATGL or HSL was not altered. Macrophage activation altered gene expression similarly when incubated with exogenous FA or AcLDL. Whereas activation with ligands of TLR2 (zymosan), TLR3 (poly I:C), or TLR4 (LPS) induced alterations in macrophage gene expression, leading to TG accumulation, treatment of macrophages with cytokines had minimal effects. Thus, activation of TLRs leads to accumulation of TG in macrophages by multiple pathways that may have beneficial effects in host defense but could contribute to the accelerated atherosclerosis in chronic infections and inflammatory diseases.
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Affiliation(s)
- Kenneth R Feingold
- Metabolism Section, Department of Veterans Affairs Medical Center, University of California, San Francisco, San Francisco, CA, USA.
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211
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Mottillo EP, Bloch AE, Leff T, Granneman JG. Lipolytic products activate peroxisome proliferator-activated receptor (PPAR) α and δ in brown adipocytes to match fatty acid oxidation with supply. J Biol Chem 2012; 287:25038-48. [PMID: 22685301 DOI: 10.1074/jbc.m112.374041] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
β-Adrenergic receptors (β-ARs) promote brown adipose tissue (BAT) thermogenesis by mobilizing fatty acids and inducing the expression of oxidative genes. β-AR activation increases the expression of oxidative genes by elevating cAMP, but whether lipolytic products can modulate gene expression is not known. This study examined the role that adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) plays in the induction of gene expression. Activation of brown adipocytes by β-AR agonism or 8-bromo-cyclic AMP increased the expression of PGC1α, PDK4, PPARα, uncoupling protein 1 (UCP1), and neuron-derived orphan receptor-1 (NOR-1), and concurrent inhibition of HSL reduced the induction of PGC1α, PDK4, PPARα, and UCP1 but not NOR-1. Similar results were observed in the BAT of mice following pharmacological or genetic inhibition of HSL and in brown adipocytes with stable knockdown of ATGL. Conversely, treatments that increase endogenous fatty acids elevated the expression of oxidative genes. Pharmacological antagonism and siRNA knockdown indicate that PPARα and PPARδ modulate the induction of oxidative genes by β-AR agonism. Using a live cell fluorescent reporter assay of PPAR activation, we demonstrated that ligands for PPARα and -δ, but not PPARγ, were rapidly generated at the lipid droplet surface and could transcriptionally activate PPARα and -δ. Knockdown of ATGL reduced cAMP-mediated induction of genes involved in fatty acid oxidation and oxidative phosphorylation. Consequently, ATGL knockdown reduced maximal oxidation of fatty acids, but not pyruvate, in response to cAMP stimulation. Overall, the results indicate that lipolytic products can activate PPARα and PPARδ in brown adipocytes, thereby expanding the oxidative capacity to match enhanced fatty acid supply.
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Affiliation(s)
- Emilio P Mottillo
- Center for Integrative Metabolic and Endocrine Research, Cardiovascular Research Institute, Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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212
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Wang JC, Gray NE, Kuo T, Harris CA. Regulation of triglyceride metabolism by glucocorticoid receptor. Cell Biosci 2012; 2:19. [PMID: 22640645 PMCID: PMC3419133 DOI: 10.1186/2045-3701-2-19] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 05/28/2012] [Indexed: 12/11/2022] Open
Abstract
Glucocorticoids are steroid hormones that play critical and complex roles in the regulation of triglyceride (TG) homeostasis. Depending on physiological states, glucocorticoids can modulate both TG synthesis and hydrolysis. More intriguingly, glucocorticoids can concurrently affect these two processes in adipocytes. The metabolic effects of glucocorticoids are conferred by intracellular glucocorticoid receptors (GR). GR is a transcription factor that, upon binding to glucocorticoids, regulates the transcriptional rate of specific genes. These GR primary target genes further initiate the physiological and pathological responses of glucocorticoids. In this article, we overview glucocorticoid-regulated genes, especially those potential GR primary target genes, involved in glucocorticoid-regulated TG metabolism. We also discuss transcriptional regulators that could act with GR to participate in these processes. This knowledge is not only important for the fundamental understanding of steroid hormone actions, but also are essential for future therapeutic interventions against metabolic diseases associated with aberrant glucocorticoid signaling, such as insulin resistance, dyslipidemia, central obesity and hepatic steatosis.
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Affiliation(s)
- Jen-Chywan Wang
- Department of Nutritional Science & Toxicology, University of California at Berkeley, Berkeley, CA, 94720, USA.
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213
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Gormley M, Tchafa A, Meng R, Zhong Z, Quong AA. Proteomic profiling of infiltrating ductal carcinoma reveals increased cellular interactions with tissue microenvironment. J Proteome Res 2012; 11:2236-46. [PMID: 22356716 DOI: 10.1021/pr201018y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Progression of invasive carcinoma involves the deregulation of molecular signaling pathways that results in the acquisition of oncogenic phenotypes. Functional enrichment analysis allows for the identification of deregulated pathways from omics scale expression data. Given the importance of post-transcriptional regulatory mechanisms on protein expression and function, identification of deregulated pathways on the basis of protein expression data is likely to provide new insights. In this study, we have developed methods for label-based mass spectrometry in a large number of samples and applied these methods toward identification and quantification of protein expression in samples of infiltrating ductal carcinoma, benign breast growths, and normal adjacent tissue. We identified 265 proteins with differential expression patterns in infiltrating ductal carcinoma relative to benign growths or normal breast tissue. Analysis of the differentially expressed proteins indicated the deregulation of signaling pathways related to proliferation, invasion and metastasis, and immune response. Our approach provides complementary information to gene expression microarray data and identifies a number of deregulated molecular signaling pathways indicative of breast cancer progression that may enable more accurate, biologically relevant diagnoses and provide a stepping stone to personalized treatment.
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Affiliation(s)
- Michael Gormley
- Department of Cancer Biology, Kimmel Cancer Center, Thomas Jefferson University, 233 South 10th Street, Philadelphia, Pennsylvania 19107, United States
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214
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Xia C, Wang Z, Xu C, Zhang H. Concentrations of Plasma Metabolites, Hormones, and mRNA Abundance of Adipose Leptin and Hormone-Sensitive Lipase in Ketotic and Nonketotic Dairy Cows. J Vet Intern Med 2012; 26:415-7. [DOI: 10.1111/j.1939-1676.2011.00863.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2011] [Revised: 10/24/2011] [Accepted: 11/29/2011] [Indexed: 11/27/2022] Open
Affiliation(s)
- C. Xia
- Department of Clinical Veterinary Medicine; College of Animal Science and Veterinary Medicine; Heilongjiang Bayi Agricultural University; Daqing; Heilongjiang province; China
| | - Z. Wang
- Department of Clinical Veterinary Medicine; College of Animal Science and Veterinary Medicine; JiLin University; Changchun; China
| | - C. Xu
- Department of Clinical Veterinary Medicine; College of Animal Science and Veterinary Medicine; Heilongjiang Bayi Agricultural University; Daqing; Heilongjiang province; China
| | - H.Y. Zhang
- Department of Clinical Veterinary Medicine; College of Animal Science and Veterinary Medicine; Heilongjiang Bayi Agricultural University; Daqing; Heilongjiang province; China
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215
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Shimizu-Albergine M, Tsai LCL, Patrucco E, Beavo JA. cAMP-specific phosphodiesterases 8A and 8B, essential regulators of Leydig cell steroidogenesis. Mol Pharmacol 2012; 81:556-66. [PMID: 22232524 DOI: 10.1124/mol.111.076125] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Phosphodiesterase (PDE) 8A and PDE8B are high-affinity, cAMP-specific phosphodiesterases that are highly expressed in Leydig cells. PDE8A is largely associated with mitochondria, whereas PDE8B is broadly distributed in the cytosol. We used a new, PDE8-selective inhibitor, PF-04957325, and genetically ablated PDE8A(-/-), PDE8B(-/-) and PDE8A(-/-)/B(-/-) mice to determine roles for these PDEs in the regulation of testosterone production. PF-04957325 treatment of WT Leydig cells or MA10 cells increased steroid production but had no effect in PDE8A (-/-)/B(-/-) double-knockout cells, confirming the selectivity of the drug. Moreover, under basal conditions, cotreatment with PF-04957325 plus rolipram, a PDE4-selective inhibitor, synergistically potentiated steroid production. These results suggest that the pool(s) of cAMP regulating androgen production are controlled by PDE8s working in conjunction with PDE4. Likewise, PDE8A (-/-)/B(-/-) cells had higher testosterone production than cells from either PDE8A(-/-) or PDE8B(-/-) mice, suggesting that both PDE8s work in concert to regulate steroid production. We further demonstrate that combined inhibition of PDE8s and PDE4 greatly increased PKA activity including phosphorylation of cholesterol-ester hydrolase (CEH)/hormone-sensitive lipase (HSL). CEH/HSL phosphorylation also was increased in PDE8A(-/-)/B(-/-) cells compared with WT cells. Finally, combined inhibition of PDE8s and PDE4 increased the expression of steroidogenic acute regulatory (StAR) protein. Together these findings suggest that both PDE8A and PDE8B play essential roles to maintain low cAMP levels, thereby suppressing resting steroidogenesis by keeping CEH/HSL inactive and StAR protein expression low. They also suggest that in order for PDE inhibitor therapy to be an effective stimulator of steroidogenesis, both PDE8 isozymes and PDE4 need to be simultaneously targeted.
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216
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Lucki NC, Li D, Sewer MB. Sphingosine-1-phosphate rapidly increases cortisol biosynthesis and the expression of genes involved in cholesterol uptake and transport in H295R adrenocortical cells. Mol Cell Endocrinol 2012; 348:165-75. [PMID: 21864647 PMCID: PMC3508734 DOI: 10.1016/j.mce.2011.08.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 07/26/2011] [Accepted: 08/03/2011] [Indexed: 12/22/2022]
Abstract
In the acute phase of adrenocortical steroidogenesis, adrenocorticotrophin (ACTH) activates a cAMP/PKA-signaling pathway that promotes the transport of free cholesterol to the inner mitochondrial membrane. We have previously shown that ACTH rapidly stimulates the metabolism of sphingolipids and the secretion of sphingosine-1-phosphate (S1P) in H295R cells. In this study, we examined the effect of S1P on genes involved in the acute phase of steroidogenesis. We show that S1P increases the expression of steroidogenic acute regulatory protein (StAR), 18-kDa translocator protein (TSPO), low-density lipoprotein receptor (LDLR), and scavenger receptor class B type I (SR-BI). S1P-induced StAR mRNA expression requires Gα(i) signaling, phospholipase C (PLC), Ca(2+)/calmodulin-dependent kinase II (CamKII), and ERK1/2 activation. S1P also increases intracellular Ca(2+), the phosphorylation of hormone sensitive lipase (HSL) at Ser(563), and cortisol secretion. Collectively, these findings identify multiple roles for S1P in the regulation of glucocorticoid biosynthesis.
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Affiliation(s)
- Natasha C. Lucki
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332-0230
| | - Donghui Li
- Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093-0704
| | - Marion B. Sewer
- Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093-0704
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217
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Ben Ali Y, Verger R, Carrière F, Petry S, Muller G, Abousalham A. The molecular mechanism of human hormone-sensitive lipase inhibition by substituted 3-phenyl-5-alkoxy-1,3,4-oxadiazol-2-ones. Biochimie 2012; 94:137-45. [DOI: 10.1016/j.biochi.2011.09.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Accepted: 09/29/2011] [Indexed: 10/16/2022]
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218
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Ali YB, Verger R, Abousalham A. Lipases or esterases: does it really matter? Toward a new bio-physico-chemical classification. Methods Mol Biol 2012; 861:31-51. [PMID: 22426710 DOI: 10.1007/978-1-61779-600-5_2] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Carboxylester hydrolases, commonly named esterases, consist of a large spectrum of enzymes defined by their ability to catalyze the hydrolysis of carboxylic ester bonds and are widely distributed among animals, plants, and microorganisms. Lipases are lipolytic enzymes which constitute a special class of carboxylic esterases capable of releasing long-chain fatty acids from natural water-insoluble carboxylic esters. However, up to now, several unsuccessful attempts aimed at differentiating "lipases" from "esterases" by using various criteria. These criteria were based on the first substrate used chronologically, primary sequence comparisons, some kinetic parameters, or some structural features.Lipids are biological compounds which, by definition, are insoluble in water. Taking into account this basic physico-chemical criterion, we primarily distinguish lipolytic esterases (L, acting on lipids) from nonlipolytic esterases (NL, not acting on lipids). In view of the biochemical data accumulated up to now, we proposed a new classification of esterases based on various criteria of physico-chemical, chemical, anatomical, or cellular nature. We believe that the present attempt matters scientifically for several reasons: (1) to help newcomers in the field, performing a few key experiments to figure out if a newly isolated esterase is lipolytic or not; (2) to clarify a debate between scientists in the field; and (3) to formulate questions which are relevant to the still unsolved problem of the structure-function relationships of esterases.
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Affiliation(s)
- Yassine Ben Ali
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, University of Sfax, Sfax, Tunisia
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219
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Parathath S, Dogan S, Joaquin VA, Ghosh S, Guo L, Weibel GL, Rothblat GH, Harrison EH, Fisher EA. Rat carboxylesterase ES-4 enzyme functions as a major hepatic neutral cholesteryl ester hydrolase. J Biol Chem 2011; 286:39683-92. [PMID: 21937439 PMCID: PMC3220591 DOI: 10.1074/jbc.m111.258095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 09/07/2011] [Indexed: 12/14/2022] Open
Abstract
Although esterification of free cholesterol to cholesteryl ester in the liver is known to be catalyzed by the enzyme acyl-coenzyme A:cholesterol acyltransferase, ACAT, the neutral cholesteryl ester hydrolase (nCEH) that catalyzes the reverse reaction has remained elusive. Because cholesterol undergoes continuous cycling between free and esterified forms, the steady-state concentrations in the liver of the two species and their metabolic availability for pathways, such as lipoprotein assembly and bile acid synthesis, depend upon nCEH activity. On the basis of the general characteristics of the family of rat carboxylesterases, we hypothesized that one member, ES-4, was a promising candidate as a hepatic nCEH. Using under- and overexpression approaches, we provide multiple lines of evidence that establish ES-4 as a bona fide endogenous nCEH that can account for the majority of cholesteryl ester hydrolysis in transformed rat hepatic cells and primary rat hepatocytes.
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Affiliation(s)
- Saj Parathath
- From the Department of Medicine and the Marc and Ruti Bell Vascular Biology Program, New York University Medical Center, New York, New York 10016
| | - Snjezana Dogan
- From the Department of Medicine and the Marc and Ruti Bell Vascular Biology Program, New York University Medical Center, New York, New York 10016
| | - Victor A. Joaquin
- From the Department of Medicine and the Marc and Ruti Bell Vascular Biology Program, New York University Medical Center, New York, New York 10016
| | - Snigdha Ghosh
- the Department of Human Nutrition, Ohio State University, Columbus, Ohio 43210, and
| | - Liang Guo
- From the Department of Medicine and the Marc and Ruti Bell Vascular Biology Program, New York University Medical Center, New York, New York 10016
| | - Ginny L. Weibel
- the Joseph Stokes Jr. Research Institute, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - George H. Rothblat
- the Joseph Stokes Jr. Research Institute, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Earl H. Harrison
- the Department of Human Nutrition, Ohio State University, Columbus, Ohio 43210, and
| | - Edward A. Fisher
- From the Department of Medicine and the Marc and Ruti Bell Vascular Biology Program, New York University Medical Center, New York, New York 10016
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220
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Miller WL, Bose HS. Early steps in steroidogenesis: intracellular cholesterol trafficking. J Lipid Res 2011; 52:2111-2135. [PMID: 21976778 DOI: 10.1194/jlr.r016675] [Citation(s) in RCA: 361] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Steroid hormones are made from cholesterol, primarily derived from lipoproteins that enter cells via receptor-mediated endocytosis. In endo-lysosomes, cholesterol is released from cholesterol esters by lysosomal acid lipase (LAL; disordered in Wolman disease) and exported via Niemann-Pick type C (NPC) proteins (disordered in NPC disease). These diseases are characterized by accumulated cholesterol and cholesterol esters in most cell types. Mechanisms for trans-cytoplasmic cholesterol transport, membrane insertion, and retrieval from membranes are less clear. Cholesterol esters and "free" cholesterol are enzymatically interconverted in lipid droplets. Cholesterol transport to the cholesterol-poor outer mitochondrial membrane (OMM) appears to involve cholesterol transport proteins. Cytochrome P450scc (CYP11A1) then initiates steroidogenesis by converting cholesterol to pregnenolone on the inner mitochondrial membrane (IMM). Acute steroidogenic responses are regulated by cholesterol delivery from OMM to IMM, triggered by the steroidogenic acute regulatory protein (StAR). Chronic steroidogenic capacity is determined by CYP11A1 gene transcription. StAR mutations cause congenital lipoid adrenal hyperplasia, with absent steroidogenesis, potentially lethal salt loss, and 46,XY sex reversal. StAR mutations initially destroy most, but not all steroidogenesis; low levels of StAR-independent steroidogenesis are lost later due to cellular damage, explaining the clinical findings. Rare P450scc mutations cause a similar syndrome. This review addresses these early steps in steroid biosynthesis.
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Affiliation(s)
- Walter L Miller
- Department of Pediatrics, School of Medicine, University of California, San Francisco, CA 94143; UCSF Benioff Children's Hospital, San Francisco, CA 94143.
| | - Himangshu S Bose
- Department of Biochemistry, Mercer University School of Medicine, Savannah, GA 31404; and; Memorial University Medical Center, Savannah, GA 31404
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221
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Yang X, Zhang X, Heckmann BL, Lu X, Liu J. Relative contribution of adipose triglyceride lipase and hormone-sensitive lipase to tumor necrosis factor-α (TNF-α)-induced lipolysis in adipocytes. J Biol Chem 2011; 286:40477-85. [PMID: 21969372 DOI: 10.1074/jbc.m111.257923] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
TNF-α potently stimulates basal lipolysis in adipocytes, which may contribute to hyperlipidemia and peripheral insulin resistance in obesity. Recent studies show that adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) act sequentially in catalyzing the first two steps of adipose lipolysis in response to β-adrenergic stimulation. Here, we sought to determine their functional roles in TNF-α-induced lipolysis. Silencing of ATGL expression in adipocytes almost completely abolished basal and TNF-α-induced glycerol release. In comparison, the glycerol release under the same conditions was only partially decreased upon reduction in expression of either HSL or the ATGL coactivator CGI-58. Interestingly, overexpression of ATGL restored the lipolytic rates in cells with silenced HSL or CGI-58, indicating a predominant role for ATGL. While expression of ATGL, HSL and CGI-58 remains mostly unaffected, TNF-α treatment caused a rapid abrogation of the ATGL inhibitory protein G0S2. TNF-α drastically decreased the level of G0S2 mRNA, and the level of G0S2 protein could be maintained by inhibiting proteasomal protein degradation using MG-132. Furthermore, coexpression of G0S2 was able to significantly decrease TNF-α-stimulated lipolysis mediated by overexpressed ATGL or CGI-58. We propose that the early reduction in G0S2 content is permissive for TNF-α-induced lipolysis.
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Affiliation(s)
- Xingyuan Yang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona 85259, USA
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222
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Abstract
Dyslipidemia associated with obesity and the metabolic syndrome is one of the central features contributing to the increased CV risk in these patients. In view of the pandemic of the metabolic syndrome, it is imperative to fully understand the mechanisms leading to the metabolic lipid phenotype before embarking upon optimal treatment strategies. The traditional concept that insulin resistance causes increased FFA flux via increased TG hydrolysis in adipose tissue is still of a central theme in the general hypothesis. The combination of increased hepatic VLDL secretion with impaired LPL-mediated TG clearance explains the hypertriglyceridemia phenotype of the metabolic syndrome. Hence, central IR may be an important factor contributing to peripheral hypertriglyceridemia. Recently recognized regulatory systems include the profound impact of the hypothalamus on TG secretion and glucose control. In addition, dysfunctional (or inflamed) intra abdominal adipose tissue has emerged as a potent regulator of dyslipidemia and IR. It will be a challenge to design novel treatment modalities that target “dysfunctional” fat or central IR to attempt to prevent the epidemic of CV disease secondary to the metabolic syndrome.
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Affiliation(s)
- Remco Franssen
- Department of Vascular Medicine, Academic Medical Center, Meibergdreef 9, Room F4-159.2, 1105 AZ, Amsterdam, The Netherlands
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223
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Higashino-Matsui Y, Shirato K, Suzuki Y, Kawashima Y, Someya Y, Sato S, Shiraishi A, Jinde M, Matsumoto A, Ideno H, Tachiyashiki K, Imaizumi K. Age-related effects of fasting on ketone body production during lipolysis in rats. Environ Health Prev Med 2011; 17:157-63. [PMID: 21850422 DOI: 10.1007/s12199-011-0231-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 07/14/2011] [Indexed: 10/17/2022] Open
Abstract
OBJECTIVE The age-related effects of fasting on lipolysis, the production of ketone bodies, and plasma insulin levels were studied in male 3-, 8-, and 32-week-old Sprague-Dawley rats. METHODS The rats were divided into fasting and control groups. The 3-, 8- and 32-week-old rats tolerated fasting for 2, 5, and 12 days, respectively. RESULTS Fasting markedly reduced the weights of perirenal and periepididymal white adipose tissues in rats in the three age groups. The mean rates of reduction in both these adipose tissue weights during fasting periods were higher in the order of 3 > 8 > 32-week-old rats. Fasting transiently increased plasma free fatty acid (FFA), total ketone body, β-hydroxybutyrate, and acetoacetate concentrations in the rats in the three age groups. However, plasma FFA, total ketone body, β-hydroxybutyrate, and acetoacetate concentrations in the 3-week-old rats reached maximal peak within 2 days after the onset of fasting, although these concentrations in the 8- and 32-week-old rats took more than 2 days to reach the maximal peak. By contrast, the augmentation of plasma FFA, total ketone body, β-hydroxybutyrate, and acetoacetate concentrations in the rats in the three age groups had declined at the end of each experimental period. Thus, the capacity for fat mobilization was associated with tolerance to fasting. Plasma insulin concentrations in the rats in the three age groups were dramatically reduced during fasting periods, although basal levels of insulin were higher in the order of 32 > 8 > 3 week-old rats. CONCLUSION These results suggest that differences in fat metabolism patterns among rats in the three age groups during prolonged fasting were partly reflected the metabolic turnover rates, plasma insulin levels, and amounts of fat storage.
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Affiliation(s)
- Yuriko Higashino-Matsui
- Laboratory of Physiological Sciences, School of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan
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224
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Ye L, Zhang B, Seviour EG, Tao KX, Liu XH, Ling Y, Chen JY, Wang GB. Monoacylglycerol lipase (MAGL) knockdown inhibits tumor cells growth in colorectal cancer. Cancer Lett 2011; 307:6-17. [DOI: 10.1016/j.canlet.2011.03.007] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2011] [Revised: 03/09/2011] [Accepted: 03/11/2011] [Indexed: 01/29/2023]
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225
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Li L, Miao Z, Liu R, Yang M, Liu H, Yang G. Liraglutide prevents hypoadiponectinemia-induced insulin resistance and alterations of gene expression involved in glucose and lipid metabolism. Mol Med 2011; 17:1168-78. [PMID: 21785811 DOI: 10.2119/molmed.2011.00051] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Accepted: 07/08/2011] [Indexed: 12/16/2022] Open
Abstract
Liraglutide is a glucagonlike peptide (GLP)-1 analog that reduces blood glucose levels, increases insulin secretion and improves insulin sensitivity through mechanisms that are not completely understood. Therefore, we aimed to evaluate the metabolic impact and underlying mechanisms of liraglutide in a hypoadiponectinemia and high-fat diet (HFD)-induced insulin resistance (IR) model. Adiponectin gene targeting was achieved using adenovirus-transduced RNAi and was used to lower plasma adiponectin levels. Liraglutide (1 mg/kg) was given twice daily for 8 wks to HFD-fed apolipoprotein (Apo)E⁻/⁻ mice. Insulin sensitivity was examined by a hyperinsulinemic-euglycemic clamp. Gene mRNA and protein expressions were measured by quantitative real-time polymerase chain reaction (PCR) and Western blot, respectively. Administration of liraglutide prevented hypoadiponectinemia-induced increases in plasma insulin, free fatty acids, triglycerides and total cholesterol. Liraglutide also attenuated hypoadiponectinemia-induced deterioration in peripheral and hepatic insulin sensitivity and alterations in key regulatory factors implicated in glucose and lipid metabolism. These findings demonstrated for the first time that liraglutide could be used to rescue IR induced by hypoadiponectinemia and HFD via regulating gene and protein expression involved in glucose and lipid metabolism.
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Affiliation(s)
- Ling Li
- Key Laboratory of Diagnostic Medicine (Ministry of Education) and Department of Clinical Biochemistry, Chongqing Medical University College of Laboratory Medicine, Chongqing, China.
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226
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Mottillo EP, Granneman JG. Intracellular fatty acids suppress β-adrenergic induction of PKA-targeted gene expression in white adipocytes. Am J Physiol Endocrinol Metab 2011; 301:E122-31. [PMID: 21505145 PMCID: PMC3129835 DOI: 10.1152/ajpendo.00039.2011] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
β-Adrenergic receptor (β-AR) activation elevates cAMP levels in fat cells and triggers both metabolic and transcriptional responses; however, the potential interactions between these pathways are poorly understood. This study investigated whether lipolysis affects β-AR-mediated gene expression in adipocytes. Acute β(3)-adrenergic receptor (β(3)-AR) stimulation with CL 316,243 (CL) increased expression of PKA-targeted genes PCG-1α, UCP1, and NOR-1 in mouse white fat. Limiting lipolysis via inhibition of hormone-sensitive lipase (HSL), a direct target of PKA, sharply potentiated CL induction of PCG-1α, UCP1, and NOR-1. CL also induced greater expression of PKA-targeted genes in white fat of HSL-null mice compared with wild-type littermates, further indicating that HSL activity limits PKA-mediated gene expression. Inhibiting HSL in 3T3-L1 adipocytes also potentiated the induction of PGC-1α, UCP1, and NOR-1 by β-AR activation, as did siRNA knockdown of adipose triglyceride lipase, the rate-limiting enzyme for lipolysis. Conversely, treatments that promote intracellular fatty acid accumulation suppressed induction of PGC-1α and UCP1 through β-AR stimulation. Analysis of β-adrenergic signaling indicated that excessive intracellular fatty acid production inhibits adenylyl cyclase activity and thereby reduces PKA signaling to the nucleus. Lastly, partially limiting lipolysis by inhibition of HSL increased the induction of oxidative gene expression and mitochondrial electron transport chain activity in white adipose tissue and facilitated fat loss in mice treated for 5 days with CL. Overall, our results demonstrate that fatty acids limit the upregulation of β-AR-responsive genes in white adipocytes and suggest that limiting lipolysis may be a novel means of enhancing β-AR signaling.
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MESH Headings
- 3T3-L1 Cells
- Adipocytes, White/drug effects
- Adipocytes, White/metabolism
- Animals
- Coenzyme A Ligases/antagonists & inhibitors
- Cyclic AMP-Dependent Protein Kinases/physiology
- Down-Regulation/drug effects
- Enzyme Inhibitors/pharmacology
- Fatty Acids/metabolism
- Fatty Acids/pharmacology
- Female
- Gene Expression/drug effects
- Intracellular Space/metabolism
- Lipolysis/drug effects
- Lipolysis/genetics
- Male
- Mice
- Mice, Inbred C57BL
- Receptors, Adrenergic, beta/genetics
- Receptors, Adrenergic, beta/metabolism
- Receptors, Adrenergic, beta-3/genetics
- Receptors, Adrenergic, beta-3/metabolism
- Triazenes/pharmacology
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Affiliation(s)
- Emilio P Mottillo
- Center for Integrative Metabolic and Endocrine Research, Department of Pathology and Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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227
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Long JZ, Cravatt BF. The metabolic serine hydrolases and their functions in mammalian physiology and disease. Chem Rev 2011; 111:6022-63. [PMID: 21696217 DOI: 10.1021/cr200075y] [Citation(s) in RCA: 299] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jonathan Z Long
- The Skaggs Institute for Chemical Biology and Department of Chemical Physiology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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228
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McDonough PM, Ingermanson RS, Loy PA, Koon ED, Whittaker R, Laris CA, Hilton JM, Nicoll JB, Buehrer BM, Price JH. Quantification of hormone sensitive lipase phosphorylation and colocalization with lipid droplets in murine 3T3L1 and human subcutaneous adipocytes via automated digital microscopy and high-content analysis. Assay Drug Dev Technol 2011; 9:262-80. [PMID: 21186937 PMCID: PMC3102254 DOI: 10.1089/adt.2010.0302] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Lipolysis in adipocytes is associated with phosphorylation of hormone sensitive lipase (HSL) and translocation of HSL to lipid droplets. In this study, adipocytes were cultured in a high-throughput format (96-well dishes), exposed to lipolytic agents, and then fixed and labeled for nuclei, lipid droplets, and HSL (or HSL phosphorylated on serine 660 [pHSLser660]). The cells were imaged via automated digital fluorescence microscopy, and high-content analysis (HCA) methods were used to quantify HSL phosphorylation and the degree to which HSL (or pHSLser660) colocalizes with the lipid droplets. HSL:lipid droplet colocalization was quantified through use of Pearson's correlation, Mander's M1 Colocalization, and the Tanimoto coefficient. For murine 3T3L1 adipocytes, isoproterenol, Lys-γ3-melanocyte stimulating hormone, and forskolin elicited the appearance and colocalization of pHSLser660, whereas atrial natriuretic peptide (ANP) did not. For human subcutaneous adipocytes, isoproterenol, forskolin, and ANP activated HSL phosphorylation/colocalization, but Lys-γ3-melanocyte stimulating hormone had little or no effect. Since ANP activates guanosine 3',5'-cyclic monophosphate (cGMP)-dependent protein kinase, HSL serine 660 is likely a substrate for cGMP-dependent protein kinase in human adipocytes. For both adipocyte model systems, adipocytes with the greatest lipid content displayed the greatest lipolytic responses. The results for pHSLser660 were consistent with release of glycerol by the cells, a well-established assay of lipolysis, and the HCA methods yielded Z' values >0.50. The results illustrate several key differences between human and murine adipocytes and demonstrate advantages of utilizing HCA techniques to study lipolysis in cultured adipocytes.
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229
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Shen WJ, Liu LF, Patel S, Kraemer FB. Hormone-sensitive lipase-knockout mice maintain high bone density during aging. FASEB J 2011; 25:2722-30. [PMID: 21566206 DOI: 10.1096/fj.11-181016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We tested the hypothesis that the actions of hormone-sensitive lipase (HSL) affect the microenvironment of the bone marrow and that removal of HSL function by gene deletion maintains high bone mass in aging mice. We compared littermate control wild-type (WT) and HSL(-/-) mice during aging for changes in serum biochemical values, trabecular bone density using micro-computed tomography, bone histomorphometry, and characteristics of primary bone marrow cells and preosteoblasts. There is a regulated expression of HSL and genes involved in lipid metabolism in the bone marrow during aging. HSL(-/-) mice have increased serum levels of insulin and osteocalcin with decreased leptin levels. Compared with the marked adipocyte infiltration in WT bone marrow (65% by area) at 14 mo, HSL(-/-) mice have fewer (16%, P<0.05) and smaller adipocytes in bone marrow. While peak bone density is similar, HSL(-/-) mice maintain a higher bone density (bone volume/total volume 6.1%) with age than WT mice (2.6%, P<0.05). Primary osteoblasts from HSL(-/-) mice show increased growth rates and higher osteogenic potential, manifested by increased expression of Runx2 (3.5-fold, P<0.05) and osteocalcin (4-fold, P<0.05). The absence of HSL directs cells within the bone marrow toward osteoblast differentiation and favors the maintenance of bone density with aging.
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Affiliation(s)
- Wen-Jun Shen
- Division of Endocrinology, Stanford University, Stanford, CA 94305-5103, USA
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230
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Vihma V, Tikkanen MJ. Fatty acid esters of steroids: synthesis and metabolism in lipoproteins and adipose tissue. J Steroid Biochem Mol Biol 2011; 124:65-76. [PMID: 21277977 DOI: 10.1016/j.jsbmb.2011.01.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 01/18/2011] [Accepted: 01/19/2011] [Indexed: 12/21/2022]
Abstract
At the end of the last century ideas concerning the physiological role of the steroid fatty acid ester family were emerging. Estrogens, fatty acylated at C-17 hydroxyl group and incorporated in lipoproteins were proposed to provide antioxidative protection to these particles. A large number of studies involving non-estrogenic adrenal steroids, and their fatty acylated forms, demonstrated their lipoprotein-mediated transport into cells and subsequent intracellular activation, suggesting a novel transport mechanism for lipophilic steroid derivatives. After these important advances the main focus of interest has shifted away from C-19 and C-21 steroids to fatty acylated estrogens. However, interest in their lipoprotein-mediated transport has decreased because only minute amounts of these derivatives were detected in circulating lipoproteins, and their antioxidative activity remained unconfirmed under physiological circumstances. It now appears that the overwhelming majority of estradiol in postmenopausal women resides in adipose tissue, most of it in esterified form. This is poorly reflected in plasma levels which are very low. Recent data suggest that estrogen fatty acid esters probably represent a storage form. The future focus of investigation is likely to be on firstly, the enzymatic mechanisms regulating the esterification and de-esterification of estradiol and other steroids residing in adipose tissue and secondly, on the role of insulin and other hormones in the regulation of these enzymatic mechanisms. Thirdly, as a large proportion of fatty acid esterified C-19 and C-21 non-estrogenic steroids is transported in lipoproteins and as they are important precursors of androgens and estrogens, this field should be investigated further.
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Affiliation(s)
- Veera Vihma
- Institute of Clinical Medicine, Department of Medicine, University of Helsinki, 00290 Helsinki, Finland
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231
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Meilin E, Aviram M, Hayek T. Insulin increases macrophage triglyceride accumulation under diabetic conditions through the down regulation of hormone sensitive lipase and adipose triglyceride lipase. Biofactors 2011; 37:95-103. [PMID: 21344529 DOI: 10.1002/biof.144] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Accepted: 12/19/2010] [Indexed: 12/17/2022]
Abstract
Diabetes mellitus (DM) is a major risk factor for the development of atherosclerosis, and high-serum levels of insulin are strongly associated with type 2 DM. Atherosclerosis is characterized by lipid-laden macrophage foam cell formations, which contain substantial amount of cholesterol and triglycerides (TG). This study analyzed for the first time, the effects of insulin on TG metabolism in macrophages under normal and diabetic conditions. Mouse peritoneal macrophages from C57BL6 mice were cultured under normal (5 mM) or high (diabetic condition, 25 mM) glucose concentration, with or without insulin, followed by the assessment of TGs metabolism in these cells. Under diabetic condition, insulin increased TG accumulation in macrophages by 100%, decreased cellular TG degradation by 21%, and increased C-reactive protein levels in macrophages by 83%. Insulin decreased hormone-sensitive lipase mRNA and protein expression by 28 and 60%, respectively, and adipose TG lipase (ATGL) protein expression by 36%, with no significant reduction in ATGL mRNA levels. The inhibition of insulin-mediated phosphorylation, and the addition of cyclic adenosine 3'5'-monoposphate, abolished the insulin-mediated inhibition of TGs degradation in cells. Insulin increases macrophage TGs accumulation only under diabetic conditions, suggesting that impaired glycemic control in diabetic patients treated with insulin may contribute to foam cell formations and enhanced inflammation in macrophages.
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Affiliation(s)
- Edna Meilin
- The Lipid Research Laboratory, Technion, Faculty of Medicine, The Rappaport Family Institute for Research in the Medical Science, Rambam Medical Center, Haifa, Israel
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232
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Han C, Wen X, Zheng Q, Li H. Effect of starvation on activities and mRNA expression of lipoprotein lipase and hormone-sensitive lipase in tilapia (Oreochromis niloticus x O. areus). FISH PHYSIOLOGY AND BIOCHEMISTRY 2011; 37:113-122. [PMID: 20706869 DOI: 10.1007/s10695-010-9423-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2010] [Accepted: 07/29/2010] [Indexed: 05/29/2023]
Abstract
A 4-week study was conducted to determine the effect of starvation on activities and mRNA expression of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) in hybrid tilapia (Oreochromis niloticus x O. areus). The tissue samples were sampled once a week. Results showed that body weight (BW) and hepatosomatic index (HSI) were decreased significantly (P < 0.05) during starvation. The percentages of crude fat and crude protein in the whole body and the fat content in muscle decreased significantly (P < 0.05), while the rate of moisture and crude ash increased significantly (P < 0.05). The response of LPL, HSL activities and mRNA expression in tissues was tissue dependent. The activities of LPL and HSL in muscle at day 7 were elevated by 2.5 times (P < 0.05) and 11.8 times (P < 0.05) of the value at day 0, respectively, and both then decreased to pre-starvation levels at day 14 and finally stabilized at a certain level afterward. LPL and HSL mRNA abundance in muscle remained relatively stable between 0 and 14 day; then, a significant increase was seen after 14 days. In the liver, LPL activity maintained a significantly increasing trend during starvation, while HSL activity rose dramatically at day 7 of starvation by 2.35 times (P < 0.05) and finally stabilized at a certain level. The mRNA abundance of liver LPL increased significantly during the whole process of starvation (P < 0.05), whereas the mRNA abundance of liver HSL decreased significantly at day 7 of starvation, elevating significantly afterward (P < 0.05).
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Affiliation(s)
- Chunyan Han
- College of Animal Science, South China Agricultural University, Guangzhou, China
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Stepien M, Gaudichon C, Fromentin G, Even P, Tomé D, Azzout-Marniche D. Increasing protein at the expense of carbohydrate in the diet down-regulates glucose utilization as glucose sparing effect in rats. PLoS One 2011; 6:e14664. [PMID: 21326875 PMCID: PMC3034717 DOI: 10.1371/journal.pone.0014664] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2010] [Accepted: 01/11/2011] [Indexed: 12/22/2022] Open
Abstract
High protein (HP) diet could serve as a good strategy against obesity, provoking the changes in energy metabolic pathways. However, those modifications differ during a dietary adaptation. To better understand the mechanisms involved in effect of high protein diet (HP) on limiting adiposity in rats we studied in parallel the gene expression of enzymes involved in protein and energy metabolism and the profiles of nutrients oxidation. Eighty male Wistar rats were fed a normal protein diet (NP, 14% of protein) for one week, then either maintained on NP diet or assigned to a HP diet (50% of protein) for 1, 3, 6 and 14 days. mRNA levels of genes involved in carbohydrate and lipid metabolism were measured in liver, adipose tissues, kidney and muscles by real time PCR. Energy expenditure (EE) and substrate oxidation were measured by indirect calorimetry. Liver glycogen and plasma glucose and hormones were assayed. In liver, HP feeding 1) decreased mRNA encoding glycolysis enzymes (GK, L-PK) and lipogenesis enzymes(ACC, FAS), 2) increased mRNA encoding gluconeogenesis enzymes (PEPCK), 3) first lowered, then restored mRNA encoding glycogen synthesis enzyme (GS), 4) did not change mRNA encoding β-oxidation enzymes (CPT1, ACOX1, βHAD). Few changes were seen in other organs. In parallel, indirect calorimetry confirmed that following HP feeding, glucose oxidation was reduced and fat oxidation was stable, except during the 1(st) day of adaptation where lipid oxidation was increased. Finally, this study showed that plasma insulin was lowered and hepatic glucose uptake was decreased. Taken together, these results demonstrate that following HP feeding, CHO utilization was increased above the increase in carbohydrate intake while lipogenesis was decreased thus giving a potential explanation for the fat lowering effect of HP diets.
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Affiliation(s)
- Magdalena Stepien
- INRA/AgroParisTech, CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
- INRA,CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
| | - Claire Gaudichon
- INRA/AgroParisTech, CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
- INRA,CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
| | - Gilles Fromentin
- INRA/AgroParisTech, CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
- INRA,CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
| | - Patrick Even
- INRA/AgroParisTech, CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
- INRA,CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
| | - Daniel Tomé
- INRA/AgroParisTech, CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
- INRA,CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
| | - Dalila Azzout-Marniche
- INRA/AgroParisTech, CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
- INRA,CNRH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris, France
- * E-mail:
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234
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Rivera-Pérez C, del Toro MDLÁN, García-Carreño F. Purification and characterization of an intracellular lipase from pleopods of whiteleg shrimp (Litopenaeus vannamei). Comp Biochem Physiol B Biochem Mol Biol 2011; 158:99-105. [DOI: 10.1016/j.cbpb.2010.10.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 10/08/2010] [Accepted: 10/10/2010] [Indexed: 11/26/2022]
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235
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Yue P, Jin H, Xu S, Aillaud M, Deng AC, Azuma J, Kundu RK, Reaven GM, Quertermous T, Tsao PS. Apelin decreases lipolysis via G(q), G(i), and AMPK-Dependent Mechanisms. Endocrinology 2011; 152:59-68. [PMID: 21047945 PMCID: PMC3033059 DOI: 10.1210/en.2010-0576] [Citation(s) in RCA: 123] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The release of free fatty acids (FFAs) from adipocytes (i.e. lipolysis) is increased in obesity and is a contributory factor to the development of insulin resistance. A recently identified adipokine, apelin, is up-regulated in states of obesity. Although apelin is secreted by adipocytes, its functions in them remain largely unknown. To determine whether apelin affects lipolysis, FFA, glycerol, and leptin levels, as well as abdominal adiposity, were measured at baseline and after reintroduction of exogenous apelin in apelin-null mice. To examine apelin's effects in vitro, isoproterenol-induced FFA/glycerol release, and hormone-sensitive lipase (HSL) and acetyl CoA carboxylase phosphorylation were investigated in 3T3-L1 cells and isolated wild-type adipocytes. Serum FFA, glycerol, and leptin concentrations, as well as abdominal adiposity, were significantly increased in apelin-null vs. wild-type mice; these changes were ameliorated in response to exogenous apelin. Apelin also reduced isoproterenol-induced FFA release in adipocytes isolated from wild-type but not APJ-null mice. In 3T3-L1 cells and isolated adipocytes, apelin attenuated isoproterenol-induced FFA/glycerol release. Apelin's inhibition was reversed by pertussis toxin, the G(q) inhibitor glycoprotein antagonist 2A, and the AMP-activated protein kinase inhibitors compound C and dorsomorphin. Apelin increased HSL phosphorylation at Ser-565 and also abrogated isoproterenol-induced HSL phosphorylation at Ser-563. Notably, apelin increased acetyl CoA carboxylase phosphorylation, suggesting AMPK activation. In conclusion, apelin negatively regulates lipolysis. Its actions may be mediated by pathways involving G(q), G(i), and AMP-activated protein kinase.
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Affiliation(s)
- Patrick Yue
- Department of Medicine/Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California 94350, USA
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236
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Sekiya M, Osuga JI, Igarashi M, Okazaki H, Ishibashi S. The Role of Neutral Cholesterol Ester Hydrolysis in Macrophage Foam Cells. J Atheroscler Thromb 2011; 18:359-64. [DOI: 10.5551/jat.7013] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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237
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Tsai LCL, Shimizu-Albergine M, Beavo JA. The high-affinity cAMP-specific phosphodiesterase 8B controls steroidogenesis in the mouse adrenal gland. Mol Pharmacol 2010; 79:639-48. [PMID: 21187369 DOI: 10.1124/mol.110.069104] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The functions of the phosphodiesterase 8B (PDE8) family of phosphodiesterases have been largely unexplored because of the unavailability of selective pharmacological inhibitors. Here, we report a novel function of PDE8B as a major regulator of adrenal steroidogenesis using a genetically ablated PDE8B mouse model as well as cell lines treated with either a new PDE8-selective inhibitor or a short hairpin RNA (shRNA) construct against PDE8B. We demonstrate that PDE8B is highly enriched in mouse adrenal fasciculata cells, and show that PDE8B knockout mice have elevated urinary corticosterone as a result of adrenal hypersensitivity toward adrenocorticotropin. Likewise, ablation of PDE8B mRNA transcripts by an shRNA construct potentiates steroidogenesis in the commonly used Y-1 adrenal cell line. We also observed that the PDE8-selective inhibitor (PF-04957325) potentiates adrenocorticotropin stimulation of steroidogenesis by increasing cAMP-dependent protein kinase activity in both primary isolated adrenocortical cells and Y-1 cells. It is noteworthy that PDE8s have their greatest control under low adrenocorticotropin-stimulated conditions, whereas other higher K(m) PDE(s) modulate steroidogenesis more effectively when cells are fully stimulated. Finally, both genetic ablation of PDE8B and long-term pharmacological inhibition of PDE8s cause increased expression of steroidogenic enzymes. We conclude that PDE8B is a major regulator of one or more pools of cAMP that promote steroidogenesis via both short- and long-term mechanisms. These findings further suggest PDE8B as a potential therapeutic target for the treatment of several different adrenal diseases.
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Affiliation(s)
- Li-Chun Lisa Tsai
- University of Washington, Department of Pharmacology, Seattle, WA 98195-7280, USA
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238
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Igarashi M, Osuga JI, Uozaki H, Sekiya M, Nagashima S, Takahashi M, Takase S, Takanashi M, Li Y, Ohta K, Kumagai M, Nishi M, Hosokawa M, Fledelius C, Jacobsen P, Yagyu H, Fukayama M, Nagai R, Kadowaki T, Ohashi K, Ishibashi S. The Critical Role of Neutral Cholesterol Ester Hydrolase 1 in Cholesterol Removal From Human Macrophages. Circ Res 2010; 107:1387-95. [DOI: 10.1161/circresaha.110.226613] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Masaki Igarashi
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Jun-ichi Osuga
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Hiroshi Uozaki
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Motohiro Sekiya
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Shuichi Nagashima
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Manabu Takahashi
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Satoru Takase
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Mikio Takanashi
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Yongxue Li
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Keisuke Ohta
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Masayoshi Kumagai
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Makiko Nishi
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Masakiyo Hosokawa
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Christian Fledelius
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Poul Jacobsen
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Hiroaki Yagyu
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Masashi Fukayama
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Ryozo Nagai
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Takashi Kadowaki
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Ken Ohashi
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
| | - Shun Ishibashi
- From the Departments of Metabolic Diseases (M.I., M.S., S.T., M. Takanashi, Y.L., K. Ohta, M.K., M.N., T.K., K. Ohashi), Pathology (H.U., M.F.), and Cardiovascular Medicine (R.N.), Graduate School of Medicine, University of Tokyo, Japan; Division of Endocrinology and Metabolism (J.-i.O., S.N., M.T., H.Y., S.I.), the Department of Medicine, Jichi Medical University, Tochigi, Japan; Faculty of Pharmaceutical Sciences, Chiba Institute of Science (M.H.), Japan; and Diabetes Research Unit (C.F., P.J.),
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239
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Abrogation of neutral cholesterol ester hydrolytic activity causes adrenal enlargement. Biochem Biophys Res Commun 2010; 404:254-60. [PMID: 21111707 DOI: 10.1016/j.bbrc.2010.11.103] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 11/23/2010] [Indexed: 11/20/2022]
Abstract
We have previously demonstrated that neutral cholesterol ester hydrolase 1 (Nceh1) regulates foam cell formation and atherogenesis through the catalytic activity of cholesterol ester hydrolysis, and that Nceh1 and hormone-sensitive lipase (Lipe) are responsible for the majority of neutral cholesterol ester hydrolase activity in macrophages. There are several cholesterol ester-metabolizing tissues and cells other than macrophages, among which adrenocortical cells are also known to utilize the intracellular cholesterol for steroidogenesis. It has been believed that the mobilization of intracellular cholesterol ester in adrenal glands was facilitated solely by Lipe. We herein demonstrate that Nceh1 is also involved in cholesterol ester hydrolysis in adrenal glands. While Lipe deficiency remarkably reduced the neutral cholesterol ester hydrolase activity in adrenal glands as previously reported, additional inactivation of Nceh1 gene completely abrogated the activity. Adrenal glands were enlarged in proportion to the degree of reduced neutral cholesterol ester hydrolase activity, and the enlargement of adrenal glands and the accumulation of cholesterol esters were most pronounced in the Nceh1/Lipe double-deficient mice. Thus Nceh1 is involved in the adrenal cholesterol metabolism, and the cholesterol ester hydrolytic activity in adrenal glands is associated with the organ enlargement.
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240
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Lass A, Zimmermann R, Oberer M, Zechner R. Lipolysis - a highly regulated multi-enzyme complex mediates the catabolism of cellular fat stores. Prog Lipid Res 2010; 50:14-27. [PMID: 21087632 PMCID: PMC3031774 DOI: 10.1016/j.plipres.2010.10.004] [Citation(s) in RCA: 454] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 10/12/2010] [Accepted: 10/13/2010] [Indexed: 12/17/2022]
Abstract
Lipolysis is the biochemical pathway responsible for the catabolism of triacylglycerol (TAG) stored in cellular lipid droplets. The hydrolytic cleavage of TAG generates non-esterified fatty acids, which are subsequently used as energy substrates, essential precursors for lipid and membrane synthesis, or mediators in cell signaling processes. Consistent with its central importance in lipid and energy homeostasis, lipolysis occurs in essentially all tissues and cell types, it is most abundant, however, in white and brown adipose tissue. Over the last 5years, important enzymes and regulatory protein factors involved in lipolysis have been identified. These include an essential TAG hydrolase named adipose triglyceride lipase (ATGL) [annotated as patatin-like phospholipase domain-containing protein A2], the ATGL activator comparative gene identification-58 [annotated as α/β hydrolase containing protein 5], and the ATGL inhibitor G0/G1 switch gene 2. Together with the established hormone-sensitive lipase [annotated as lipase E] and monoglyceride lipase, these proteins constitute the basic "lipolytic machinery". Additionally, a large number of hormonal signaling pathways and lipid droplet-associated protein factors regulate substrate access and the activity of the "lipolysome". This review summarizes the current knowledge concerning the enzymes and regulatory processes governing lipolysis of fat stores in adipose and non-adipose tissues. Special emphasis will be given to ATGL, its regulation, and physiological function.
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Affiliation(s)
- Achim Lass
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
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241
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Schicher M, Morak M, Birner-Gruenberger R, Kayer H, Stojcic B, Rechberger G, Kollroser M, Hermetter A. Functional Proteomic Analysis of Lipases and Esterases in Cultured Human Adipocytes. J Proteome Res 2010; 9:6334-44. [DOI: 10.1021/pr1005795] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Maximilian Schicher
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
| | - Maria Morak
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
| | - Ruth Birner-Gruenberger
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
| | - Heidemarie Kayer
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
| | - Bojana Stojcic
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
| | - Gerald Rechberger
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
| | - Manfred Kollroser
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
| | - Albin Hermetter
- Institute of Biochemistry, Graz University of Technology, Graz, Austria, Institute of Molecular Biosciences, University of Graz, Graz, Austria, and Institute of Forensic Medicine, Medical University of Graz, Graz, Austria
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Shen WJ, Yu Z, Patel S, Jue D, Liu LF, Kraemer FB. Hormone-sensitive lipase modulates adipose metabolism through PPARγ. Biochim Biophys Acta Mol Cell Biol Lipids 2010; 1811:9-16. [PMID: 20950707 DOI: 10.1016/j.bbalip.2010.10.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2010] [Revised: 08/26/2010] [Accepted: 10/05/2010] [Indexed: 11/20/2022]
Abstract
Hormone-sensitive lipase (HSL) is rate limiting for diacylglycerol and cholesteryl ester hydrolysis in adipose tissue and essential for complete hormone-stimulated lipolysis. Gene expression profiling in HSL-/- mice suggests that HSL is important for modulating adipogenesis and adipose metabolism. To test whether HSL is required for the supply of intrinsic ligands for PPARγ for normal adipose differentiation, HSL-/- and wild-type (WT) littermates were fed normal chow (NC) and high-fat (HF) diets supplemented with or without rosiglitazone (200 mg/kg) for 16 weeks. Results show that supplementing rosiglitazone to an NC diet completely normalized the decreased body weight and adipose depots in HSL-/- mice. Additionally, rosiglitazone resulted in similar serum glucose, total cholesterol, FFA, and adiponectin values in WT and HSL-/- mice. Furthermore, rosiglitazone normalized the expression of genes involved in adipocyte differentiation, markers of adipocyte differentiation, and enzymes involved in triacylglycerol synthesis and metabolism, and cholesteryl ester homeostasis, in HSL-/- mice. Supplementing rosiglitazone to an HF diet resulted in improved glucose tolerance in both WT and HSL-/- animals and also partial normalization in HSL-/- mice of abnormal WAT gene expression, serum chemistries, organ and body weight changes. In vitro studies showed that adipocytes from WT animals can provide ligands for activation of PPARγ and that activation is further boosted following lipolytic stimulation, whereas adipocytes from HSL-/- mice displayed attenuated activation of PPARγ, with no change following lipolytic stimulation. These results suggest that one of the mechanisms by which HSL modulates adipose metabolism is by providing intrinsic ligands or pro-ligands for PPARγ.
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Affiliation(s)
- Wen-Jun Shen
- Division of Endocrinology, Stanford University, CA 94305-5103, USA
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243
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Buchebner M, Pfeifer T, Rathke N, Chandak PG, Lass A, Schreiber R, Kratzer A, Zimmermann R, Sattler W, Koefeler H, Fröhlich E, Kostner GM, Birner-Gruenberger R, Chiang KP, Haemmerle G, Zechner R, Levak-Frank S, Cravatt B, Kratky D. Cholesteryl ester hydrolase activity is abolished in HSL-/- macrophages but unchanged in macrophages lacking KIAA1363. J Lipid Res 2010; 51:2896-908. [PMID: 20625037 PMCID: PMC2936755 DOI: 10.1194/jlr.m004259] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 07/12/2010] [Indexed: 12/24/2022] Open
Abstract
Cholesteryl ester (CE) accumulation in macrophages represents a crucial event during foam cell formation, a hallmark of atherogenesis. Here we investigated the role of two previously described CE hydrolases, hormone-sensitive lipase (HSL) and KIAA1363, in macrophage CE hydrolysis. HSL and KIAA1363 exhibited marked differences in their abilities to hydrolyze CE, triacylglycerol (TG), diacylglycerol (DG), and 2-acetyl monoalkylglycerol ether (AcMAGE), a precursor for biosynthesis of platelet-activating factor (PAF). HSL efficiently cleaved all four substrates, whereas KIAA1363 hydrolyzed only AcMAGE. This contradicts previous studies suggesting that KIAA1363 is a neutral CE hydrolase. Macrophages of KIAA1363(-/-) and wild-type mice exhibited identical neutral CE hydrolase activity, which was almost abolished in tissues and macrophages of HSL(-/-) mice. Conversely, AcMAGE hydrolase activity was diminished in macrophages and some tissues of KIAA1363(-/-) but unchanged in HSL(-/-) mice. CE turnover was unaffected in macrophages lacking KIAA1363 and HSL, whereas cAMP-dependent cholesterol efflux was influenced by HSL but not by KIAA1363. Despite decreased CE hydrolase activities, HSL(-/-) macrophages exhibited CE accumulation similar to wild-type (WT) macrophages. We conclude that additional enzymes must exist that cooperate with HSL to regulate CE levels in macrophages. KIAA1363 affects AcMAGE hydrolase activity but is of minor importance as a direct CE hydrolase in macrophages.
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Affiliation(s)
- Marlene Buchebner
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Thomas Pfeifer
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Nora Rathke
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Prakash G. Chandak
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Achim Lass
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Renate Schreiber
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Adelheid Kratzer
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Robert Zimmermann
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Wolfgang Sattler
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Harald Koefeler
- Center of Molecular Medicine, and Center for Medical Research, Medical University of Graz, Graz, Austria
| | - Eleonore Fröhlich
- Center of Molecular Medicine, and Center for Medical Research, Medical University of Graz, Graz, Austria
| | - Gerhard M. Kostner
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Ruth Birner-Gruenberger
- Center of Molecular Medicine, and Center for Medical Research, Medical University of Graz, Graz, Austria
| | - Kyle P. Chiang
- Skaggs Institute for Chemical Biology and Department of Chemical Physiology, Scripps Research Institute, La Jolla, CA
| | - Guenter Haemmerle
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Sanja Levak-Frank
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Benjamin Cravatt
- Skaggs Institute for Chemical Biology and Department of Chemical Physiology, Scripps Research Institute, La Jolla, CA
| | - Dagmar Kratky
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
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244
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Activation of PPARα by bezafibrate negatively affects de novo synthesis of sphingolipids in regenerating rat liver. Prostaglandins Other Lipid Mediat 2010; 93:120-5. [PMID: 20851774 DOI: 10.1016/j.prostaglandins.2010.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 08/21/2010] [Accepted: 09/02/2010] [Indexed: 11/21/2022]
Abstract
Serine palmitoyltransferase (SPT) is a key enzyme in de novo sphingolipid biosynthesis. SPT activity in liver is up-regulated by pro-inflammatory cytokines, which play an important role in initiation of liver regeneration after partial hepatectomy (PH). The aim of the study was to investigate the impact of a high-fat diet or PPARα activation by bezafibrate on the activity and protein expression of SPT in rat liver after PH. The animals were divided into three groups: those fed a standard chow (SD), those fed a high-fat diet (HFD), and those treated with bezafibrate (BF). It has been found that the expression and activity of SPT increased in regenerating liver. This was accompanied by the elevation of plasma NEFA concentration. Moreover, in both diet groups, the content of sphinganine increased. Bezafibrate decreased protein expression of SPT at the 4th and 12th hour, and inhibited SPT activity at the 4th hour after PH. Both, the plasma NEFA concentration and sphinganine content decreased in the groups treated with bezafibrate. We conclude that partial hepatectomy stimulates de novo sphingolipid synthesis. Activation of PPARα by bezafibrate negatively affects this process, presumably by decreasing the availability of plasma-borne fatty acids.
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245
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Short-term oral exposure to white wine transiently lowers serum free fatty acids. Appetite 2010; 55:124-9. [DOI: 10.1016/j.appet.2010.04.217] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2009] [Revised: 03/12/2010] [Accepted: 04/26/2010] [Indexed: 11/18/2022]
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246
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Shen WJ, Patel S, Eriksson JE, Kraemer FB. Vimentin is a functional partner of hormone sensitive lipase and facilitates lipolysis. J Proteome Res 2010; 9:1786-94. [PMID: 20143880 DOI: 10.1021/pr900909t] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Lipolysis involves a number of components including signaling pathways, droplet-associated proteins, and lipases such as hormone-sensitive lipase (HSL). We used surface enhanced laser desorption/ionization time-of-flight mass spectroscopy to identify cellular proteins that might interact with HSL and potentially influence lipolysis. Using recombinant HSL as bait on protein chips, clusters of proteins of 14.7-18.9, 25.8-26.8, 36.1, 44.3-49.1, and 53.7 kDa were identified that interact with HSL, particularly when lysates were examined from beta-agonist treated mouse adipocytes. The ability to detect these interacting proteins was markedly diminished when the adipocytes were treated with insulin. A very similar pattern of proteins was identified when anti-HSL IgG was used as the bait. Following immunocapture, the identification of the prominent 53.7 kDa protein was carried out by tryptic digestion and MS analysis and determined to be vimentin. The interaction of HSL with vimentin, and its hormonal dependence, was confirmed by coimmunoprecipitation. beta-Agonist stimulated lipolysis and the rate of HSL translocation were impaired in vimentin null adipocytes, even though normal amounts of lipases and droplet-associated proteins are expressed. The current studies provide evidence that vimentin participates in lipolysis through direct, hormonally regulated interactions with HSL.
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Affiliation(s)
- Wen-Jun Shen
- Division of Endocrinology, Stanford University and VA Palo Alto Health Care System, Palo Alto, California 94304, USA
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247
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Murrieta C, Hess B, Lake S, Scholljegerdes E, Rule D. Body condition score and day of lactation regulate fatty acid metabolism in milk somatic cells and adipose tissue of beef cows. Livest Sci 2010. [DOI: 10.1016/j.livsci.2010.02.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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248
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Genetic variation at the goat hormone-sensitive lipase (LIPE) gene and its association with milk yield and composition. J DAIRY RES 2010; 77:190-8. [DOI: 10.1017/s0022029910000099] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Hormone-sensitive lipase (LIPE) plays a fundamental role in the regulation of energy balance by releasing free fatty acids from adipose triacylglycerol stores. These fatty acids can be subsequently transferred to other body compartments to be oxidized or employed in other biochemical reactions. This enzymic function is particularly important in lactating animals because the synthesis of milk components involves the mobilization of lipid depots to satisfy the large energy demands of the mammary gland. In the current study, we partially sequenced the goatLIPEgene in several individuals. In doing so, we identified two synonymous polymorphisms at exons 2 (c.327C>A>T, triallelic polymorphism) and 3 (c.558C>T). Moreover, we found a mis-sense polymorphism at exon 6 (c.1162G>T) that involves an alanine to serine substitution at position 388. Analysis with Polyphen and Panther softwares revealed that this amino acid replacement is expected to be neutral. Performance of an association analysis with a variety of milk traits revealed that goatLIPEgenotype has highly suggestive effects on milk yield (P=0·0032) as well as on C18:3 n-6g (P=0·0051),trans-10cis-12 CLA (P=0·007) and C12:0 (P=0·0084) milk contents. These associations are concordant with the preference of LIPE to selectively mobilize medium-chain and unsaturated fatty acids.
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249
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Sun C, Wei ZW, Li Y. DHA regulates lipogenesis and lipolysis genes in mice adipose and liver. Mol Biol Rep 2010; 38:731-7. [DOI: 10.1007/s11033-010-0160-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Accepted: 06/24/2009] [Indexed: 12/12/2022]
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250
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De Santi C, Tutino ML, Mandrich L, Giuliani M, Parrilli E, Del Vecchio P, de Pascale D. The hormone-sensitive lipase from Psychrobacter sp. TA144: new insight in the structural/functional characterization. Biochimie 2010; 92:949-57. [PMID: 20382198 DOI: 10.1016/j.biochi.2010.04.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 04/02/2010] [Indexed: 11/24/2022]
Abstract
Cold-adapted esterases and lipases have been found to be dominant activities throughout the cold marine environment, indicating their importance in bacterial degradation of the organic matter. lip2 Gene from Psychrobacter sp. TA144, a micro-organism isolated from the Antarctic sea water, was cloned and over-expressed in Escherichia coli. The recombinant protein (PsyHSL) accumulated in the insoluble fraction from which it was recovered in active form, purified to homogeneity and deeply characterised. Temperature dependence of PsyHSL activity was typical of psychrophilic enzymes, with an optimal temperature of 35 degrees C at pH 8.0. The enzyme resulted to be active on pNP-esters of fatty acids with acyl chain length from C(2) to C(12) and the preferred substrate was pNP-pentanoate showing a k(cat) = 26.2 +/- 0.1 s(-1), K(M) = 0.122 +/- 0.006 mM and a k(cat)/K(M) = 215 +/- 11 mM(-1) s(-1). The enzyme was strongly inhibited by Hg(2+), Zn(2+), Cu(2+), Fe(3+), Mn(2+) ions and it resulted to be activated in presence of methanol and acetonitrile, with calculated C(50) values of 1.98 M and 0.92 M, respectively. The region surrounding PsyHSL catalytic site showed an unexpected homology with the human HSL. Further, both enzymes are characterised by the presence of an extra N-terminal domain, which role in the human protein has been related to regulative function. To clarify the function of PsyHSL N-terminal domain, a 97 amino acids deleted version of the enzyme was produced in E. coli in soluble form, purified and characterised. This mutant was inactive towards all tested substrates, indicating the involvement of this region in the catalytic process.
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Affiliation(s)
- Concetta De Santi
- Institute of Protein Biochemistry, CNR, Via Pietro Castellino 111, I-80131 Naples, Italy.
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